Dissertations / Theses: 'Mesofil'

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Karlsson, Niklas. "Foderbetor och kogödsel som substrat för biogasproduktion; anaerob mesofil samrötning i labbskala." Thesis, Halmstad University, School of Business and Engineering (SET), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-4791.

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One of Sweden’s sixteen national environmental objectives strives to decrease the impact on the climate. By 2020, green house gas emissions should be 40 % less compared to the levels of 1990 and a minimum of 50 % of the energy consumption should come from renewable energy sources. Because of this there is a great need of increasing the production of renewable energy. This is where biogas comes in as a competitive alternative. However, there is a problem. Substrates for biogas production have become a scarcity due to the increasing demand for biogas that has been expressed lately.

The objective is to co-digest fodder beet and cow manure in order to find the best methane yielding mixture(s), and based on these results be able suggest whether fodder beets are a suitable substrate to use in a greater extent. This might prove to be one possible way in dealing with today’s substrate shortage. The mesophilic co-digestion has been performed in lab scale, where seven glass bottles (800ml) have served as digesters. Several analyses of important parameters i.e. gas production and composition, carbon/nitrogen-ratio, total solids and pH have been performed during and after the digestion tests.

The best results (25-28 % methane) were obtained when 5-15 % beets were added to the digester. This shows that fodder beets is best used as a supplement in a smaller extent. Results also show that, when using fodder beets as substrate, two of the most important process parameters to control are pH and buffer capacity (alkalinity/volatile organic acid ratio). This is because the digester easily gets acidic.

Based on these results it’s hard to suggest fodder beet usage in a greater extent when being mixed with only cow manure for biogas production. This is especially true for smaller biogas plants where the possibility of observation often is limited or deficient. However, because of the rapid initial degradation and gas production, fodder beets would make a good complement in digesters where more persistent substrates with slower gas production are being digested. Also, since fodder beets are rich in carbon and poor in nitrogen they would also make a good complement when one desire to increase the carbon/nitrogen-ratio in the digester

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Andersson, Johanna. "Optimering av driftstemperatur vid mesofil rötning av slam : - funktionskontroll vid Uppsalas reningsverk." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-381615.

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För att minska klimatpåverkan är energisnåla processer och användning av fossilfria bränslen viktigt. Vid stabilisering av avloppsslam vid reningsverk är en vanlig metod rötning som förutom att ta hand om slammet även producerar biogas, ett fossilfritt bränsle med låga växthusgasutsläpp. Processer som drivs inom det mesofila temperaturområdet har visat sig vara stabila och ger en jämn gasproduktion. Det mesofila området sträcker sig mellan 25–40°C men de flesta processer drivs mellan 35–40°C. Den här studien undersöker möjligheten att sänka temperaturen inom det mesofila området för att få en lägre energiförbrukning och en energisnålare process. Då det är viktigt att biogasproduktionen inte försämras av en sänkt temperatur har skillnad i utrötningsgrad, metanpotential och utrötningstid undersökts vid tre olika temperaturer (32, 34,5 samt 37,5°C) via satsvisa utrötningsförsök. Utöver påverkan på biogasproduktionen har en energibalansberäkning utförts för rötkamrarna vid Uppsala reningsverk. Detta ger ett mått på hur stora vinster i värmeenergi en sänkt temperatur kan leda till. En betydande kostnad vid reningsverk är avvattningen av slam och det är därför viktigt att den inte riskerar att försämras om temperaturen sänks. Ett filtreringsförsök som mäter CST (Capillary Suction Time) ger ett mått på slammets avvattningsegenskaper och har därför utförts vid tre olika temperaturer. Resultaten visade ingen försämring i biogasproduktion vid en sänkning till 34,5°C och en minskning i metanpotential med 11 % vid en sänkning till 32°C. Nedbrytningshastigheten försämrades inte vid en sänkt temperatur. Vinster i form av lägre värmeförbrukning uppgick till 14 % vid sänkning till 34,5°C och 27 % vid sänkning till 32°C. Avvattningsförsöket visade ingen försämrad avvattning vid lägre temperaturer. Den här studien visar att det finns en möjlighet att sänka temperaturen i rötkammaren vid reningsverket i Uppsala och på så sätt sänka energiförbrukningen. För att bekräfta resultaten bör även kontinuerliga försök utföras men denna studie visar att det är möjligt att få en lyckad nedbrytning även i lägre mesofila temperaturer. Resultatet öppnar upp för fortsatta undersökningar om temperaturförändringar inom det mesofila området och kan leda till en optimering av rötningsprocessen och möjlighet att få en effektiv och energisnål produktion av biogas.
Energy efficient processes and the use of fossil free fuels play an important role in order to reduce the impact of climate change. Anaerobic digestion is a common way for stabilizing sewage sludge at wastewater treatment plants (WWTP). One of the benefits with anaerobic digestion is that it also produces biogas, a fossil free fuel with low greenhouse gas emissions. An operational temperature within the mesophilic range has proven to give a stable process with an unfluctuating production of gas. The mesophilic temperature range between 25-40°C but most processes are operated between 35-40°C. This study investigates the opportunity to lower the temperature within the mesophilic range in order to reduce energy consumption. It is important to maintain the production of biogas with a lower temperature. Therefore, the reduction in VS-content (VS-volatile solids), methane yield and time for degradation was determined by a BMP-experiment (BMP-Biochemical Methane Potential) in three different temperatures (32, 34.5 and 37.5°C). In order to quantify the reduction in heat consumption with lower operational temperatures the change in heat balance for a full-scale WWTP in Uppsala was calculated. A major part of the operational cost is dewatering of sludge and it is therefore important that it does not deteriorate with a lower temperature. The effect on the dewaterability at different temperatures was examined by a filterability test measuring CST (capillary suction time). The results from the study showed no significant difference in methane yield between 37.5°C and 34.5°C. The methane yield at 32°C was 11 % lower compared to 37.5°C but the degradation kinetic was not affected by a temperature change. The reduction in heat consumption was 14 % when the temperature was reduced to 34.5°C and 27 % when it was reduced to 32°C. The filterability test did not show a deterioration with lower temperatures. The study showed that it is possible to reduce the operational temperature for anaerobic digestion at the WWTP in Uppsala in order to reduce the energy consumption. To confirm these results a continuously experiment should be done, but this study shows that it is possible to get a successful degradation in a lower mesophilic temperature. This leads the way for further investigations within the mesophilic range and could lead to optimizing anaerobic digestion and the opportunity to get an energy efficient production of biogas.

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Hallin, Sara. "Biogasproduktion genom tvåstegsrötning av drankvatten." Thesis, Linköping University, Department of Water and Environmental Studies, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11182.

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During the 19-century a global warming has been observed, which includes increases in global air and ocean temperatures, widespread melting of ice and snow, and rising global sea level. There is a clear connection between emissions of greenhouse gases caused by the human and the increase in temperature. Climatic changes caused by global warming can be stopped trough decreased emission of fossil fuels, for example by an increased use of biogas. Biogas is a renewable energy source which is produced through anaerobic (oxygen free) digestion of organic material. The gas is a mixture of methane (CH4) and carbon dioxide (CO2) and can be among others used as fuel in vehicles. Greengas is biogas produced from grains.

The aim with this master’s thesis was to investigate a two-stage process for digestion of a rest by product from ethanol production, called drankvatten. Laboratory experiments were carried out with two process sets, each with two continues stirred tank reactors (CSTR). The process consisted of a thermophilic (55ºC) reactor as the first step in which the substrate was added. Afterwards there was a mesophilic (38ºC) second reactor in which the material from the first reactor was further degraded to produce more gas. The results were intended to be used for an assessment of whether a two-stage process is more efficient then a single-stage process in a full-scale production facility. One of the reasons to have a thermophilic first reactor is that the material has an average temperature around 80 ºC when it arrives to the facility today.

It was proved that a two-stage process with this type of substrate generated a higher gas production but the improvements weren’t big enough to motivate a reconstruction of the facility into a two-stage process. The thermophilic process was stable with a retention time of 15 days and a loading rate of 6 g VS/(l•dygn). This retention time was the shortest which was achieved during that loading rate. During earlier mesophilic experiments a higher loading rate was achieved however the used retention time was longer. On the basis of this work no conclusions could be drawn whether a thermophilic process could withstand a higher loading rate then a mesophilic one. Longer adaptation times is probably needed to reach higher loading rates. In this work it also has been studied if it’s necessary to have continues mixing in the biogas reactors. The conclusion of this experiment is that continues mixing isn’t necessary, which results in less mixing and in that way less energy costs.

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Simensen, Ebba. "Ska HEMAB investera i en egen rötning av avloppsslam i Härnösand vid Kattastrand?" Thesis, KTH, Skolan för kemi, bioteknologi och hälsa (CBH), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299641.

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Projektets syfte är att undersöka om HEMAB ska investera i rötning av Kattastrands avloppsslam, för att reducera mängd avloppsslam och samtidigt utvinna biogas. För att avgöra om rötning av Kattastrands avloppsslam är möjligt har en teknisk lösning för rötningen tagits fram. En ekonomisk kalkyl för den tekniska lösningar har även tagits fram. Undersökningen har även baserats på tillståndsgivning, samarbeten lokalt/regionalt och situations- och samhällsplanering. Kattastrands avloppsslam har valts att våtrötas i ett steg, vid en mesofilt temperatur på 37 °C. Rötkammaren har en volym på 855 m3, vilket motsvarar en brädd på 10 m och en höjd på 11,9 m. Rötkammaren placeras förslagsvis på HEMAB:s mark sydost om reningsverkets två befintliga processbyggnader. Rötning av slam vid Kattastrand anses inte påverka närområdet nämnvärt. Investeringsbehovet för rötanläggningen är 5,02 miljoner kr, vilket ger en investeringskostnad på 256 tusen kr per år. Rötanläggningen har även en årlig driftkostnad på 109 tusen kr. Om den producerade biogasen används för tillverkning av värme eller kraftvärme kan elen och/eller värmen användas för att täcka rötanläggningens el och/eller värmekostnader. Det skulle resultera i att driftkostnaderna för rötanläggningen kraftigt sjunker. Om rötningen medför en anmälnings- eller tillståndsplikt måste utredas av Västernorrlands länsstyrelse. Samarbeten lokalt/regionalt är möjligt vid dimensionering av en större rötkammare, men hur ett sådant samarbete skulle se ut måste undersökas vidare. Möjligheten att röta Kattastrands avloppsslam ses som god och jag rekommenderar därför HEMAB att fortsätta undersöka möjligheten att börja röta Kattastrands avloppsslam.
The purpose of this project is to investigate whether HEMAB should invest in anaerobic digestion of sewage sludge at Kattastrand. The gool is to reduce the amount of sewage sludge while at the same time producing biogas. A technical solution for the digestion has been developed to determine whether anaerobic digestion of the sewage sludge at Kattastrand is feasible. An economic calculation for the technical solutions has also been carried out. The study has also been based on required permits, partnership locally/regionally and site and community planning. The sewage sludge has been chosen to be digested in a wet, one step process, at a mesophilic temperature of 37 ° C. The digestion tank has a volume of 855 m3, which expected to a width of 10 m and a height of 11.9 m. Digestion of sludge at Kattastrand is not considered to affect the immediate surrounding area significantly. The investment need for the anaerobic digestion plant is 5.02 million SEK, which gives an investment cost of 256 thousand SEK per year. The digester also has an annual operating cost of 109 thousand SEK. If the biogas is used for production of heat or cogenerated electricity and heat, the operating costs will be greatly reduced. Whether the digestion entails a notification or permit requirement must be investigated by Västernorrland landsting Board. Locally and regionally partnerships are possible by dimensioning a larger digester tank, but what these partnerships could look like should be further investigated. The possibility to anaerobically digest the sewage sludge at Kattastrand is feasible and a good opportunity to reduce the amount of sewage sludge while at the same time producing biogas. Therefore, I recommend HEMAB to continue investigating the possibility of anaerobic digestion of the sewage sludge at Kattastrand.

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Lundgren, Maria. "En teoretisk granskning av ekonomiska, energioch miljömässiga för- och nackdelar med mesofil rötning av avloppsslam : Fallstudie på Rättviks avloppsreningsverk." Thesis, Högskolan i Gävle, Avdelningen för byggnadsteknik, energisystem och miljövetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-33213.

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Inom VA-branschen ökar energi- och miljömedvetenheten. Detta har lett till en önskan om att ta vara på resursinnehållet i avloppsslammet, vilket kan tas tillvara genom rötning. Men precis som andra slambehandlingsmetoder har rötning flera olika föroch nackdelar. Syftet med examensarbetet är att bidra till ökad kunskap gällande de generella ekonomiska samt miljö- och energimässiga för- och nackdelarna med rötning. Den första frågan som har ställts i examensarbetet är vilka för- och nackdelar som uppstår på Rättviks avloppsreningsverk vid användning av rötning respektive utan rötning. Den andra frågan som har ställts är hur nyttjandet av produkterna som bildas vid rötning kan öka. Examensarbetet har avgränsats till att fokusera på rötningens påverkan på avloppsreningsverket. Metoderna i detta arbete har varit litteratur- och dokumentsstudier samt personlig kommunikation för att inhämta relevant information. I arbetet har även en fallstudie gjorts på Rättviks avloppsreningsverk för att hämta information och granska rötning ur en verklig situation. För att svara på frågeställningarna har två olika scenarier för Rättviks avloppsreningsverk används. Scenario 1, dagens system, och Scenario 2, framtida system där rötningen har kompletterats med en gasklocka och gasmotor. Båda scenarierna redovisar styrkor som volymminskningen och färre transporter i jämförelse med om rötning inte används. Svagheter med systemen är att det är bland annat stort värmebehov på grund av att rötkammaren inte är isolerad. Vid jämförelser mellan scenario 1 och om rötning inte används redovisas teoretiska uträkningar besparingar på cirka 265 000 kronor år 2019 tack vare användningen av rötning på Rättviks avloppsreningsverk. Jämförelsen redovisar också att volymreduceringen måste vara 13 procent eller större för rötning ska bidra till besparingar. Vid jämförelse av scenario 1 och 2 redovisas en besparing på cirka 91 000, beroende på energifördelningen hos rötningen. En av slutsatserna som kunnat dras är att det troligen är lönsamt för Rättviks avloppsreningsverk att använda rötning, tack vare volymreduceringen. En annan slutsats är att åtgärder som gasklocka och gasmotor eller uppgradering till fordonsgas skulle förbättra användandet av biogasen. Dock skulle åtgärderna eventuellt inte vara ekonomiskt försvarbar i dagsläget men önskvärda i framtiden. Då belastningen troligen är högre med mer avloppsslam, vilket bidrar till en större biogasproduktion. Även ändring av slutomhändertagande och slutanvändning kan vara lämpligt för att öka nyttjande av resurserna i slammet men även på grund av framtida lagändringar.
In the water and wastewater industry, energy and environmental awareness is increasing. This has led to a desire to utilize the resources that sewage sludge contains, which can be exploited by anaerobic digestion. However, just like other sludge treatment methods, digestion has several different advantages and disadvantages. The purpose of this degree project has been to contribute to increased knowledge regarding the general economic, environmental and energy advantages and disadvantages of digestion. The first question posed in this degree project is what advantages and disadvantages the usage as well as the non-usage of anaerobic digestion has on the Rättvik water treatment plant. The second question posed is how the usage of the products created by anaerobic digestion can increase. The degree project has been limited to focusing on the effects of digestion on the wastewater treatment plant The methods used in this work have been literature and document studies as well as personal communication to obtain relevant information. In the degree project, a case study has been performed at Rättvik's wastewater treatment plant to retrieve information and review anaerobic digestion from a real situation. Two different scenarios from Rättvik's treatment plant have been used to answer the questions. Scenario 1, today's system and Scenario 2, the future system, digestion has been supplemented with a gas clock and gas engine. Both scenarios report strengths such as volume reductions and fewer transports compared to if no digestion is used. The weaknesses with the systems are that there is, among other things, a great need for heat. In comparisons between scenario 1 and if digestion is not used, savings of approximately SEK 265,000 in 2019 are reported from theoretical calculations due to the use of digestion at Rättvik's sewage treatment plant. The comparison also reports that the volume reduction must be 13 percent or higher for the digestion to contribute to savings. When comparing scenarios 1 and 2, a saving of about 91,000 is reported, depending on the energy distribution of the digestion. One of the conclusions that can be drawn is that it is probably profitable for Rättvik's wastewater treatment plant to use the digestion thanks to the volume reduction. Another conclusion is that measures such as gas holder and gas engine or upgrade to vehicle gas would improve the use of biogas. However, the measures may not be economically justified but desirable in the future as the load is higher and thus more sewage sludge and greater biogas production. Change of final disposal and end use may also be appropriate to increase utilization of the resources in the sludge, but also due to future legislative changes.

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Ebba, Lejeby. "Metanpotential för alger och bioslam blandat med pappersfiber." Thesis, Linnéuniversitetet, Institutionen för bygg- och energiteknik (BE), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-32689.

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In this thesis the methane gas potential of three different substrates, two algaes Saccharina latissima and Laminaria digitata and biosludge mixed with paper fiber was studied. This was done by batch experiments in a laboratory environment to examine the gas production and composition of the produced gas. Biogas production is a complex anaerobic digestion process in which various microorganisms decompose the substrate in steps and at the end produce biogas and a residue. Many factors affect the production of gas, for example the substrate content, temperature and pH in the digester. The analysis of methane potential were divided into two experiments. In experiment 1 substrates were digested along with inoculum from Växjö waste water treatment plant in a temperature of about 37 ˚C. In experiment 2 substrates were digested along with inoculum from Kalmar Biogas AB at about 52 ˚C. Both experiments contained 15 bottles each with three replicates for each substrate: only inoculum, inoculum + Algae 1 (Saccharina latissima), inoculum + Algae 2 (Laminaria digitata), inoculum + Paper (biosolids mixed with paper fiber), inoculum + Reference (Cellulose). The inoculum and the reference were running to assess the quality of the inoculum. Mixtures between the inoculum and the substrate was first set to 5:1 and then 4:1, based on the material's VS-concentration. All experiments went on until gas production was minimal. For experiment 1 ,with the ratio of 5:1, the end results of the accumulated methane for Algae 1, Algae 2, Paper and Reference were 315, 313, 88 and 381 Nml CH4/g VS substrate respetively. The batch with inoculum + Paper was ended after seven days because the difference between inoculum + Paper and only inoculum was small. In experiment 1, with a ratio of 4:1, inoculum + Reference and inoculum batches were not prepared mainly because of lack of space.The batch with only inoculum was assumed to give the same results as in experiment 1, with the ratio of 5:1. The end results of the accumulated methane for Algae 1, Algae 2 and Paper were: 199, 214 and 41 Nml/g VS substrate repectively For experiment 2, with the ratio of 5:1, the end results of accumulated methane for Algae 1, Algae 2, Paper and Reference were: 191, 183, 33, 243 Nml/g VS substrate respectively In experiment 2, with the ratio 4:1, the end result of accumulated methane for Algae 1, Algea 2, Paper and Reference were: 288, 179, 18, 337 Nml/g VS substrate respectively.
I detta examensarbete studerades metanpotentialen för algerna Saccharina latissima, Laminaria digitata samt bioslam blandat med pappersfiber. Detta gjordes i satsvisa försök i laboratoriemiljö där gasproduktionen och sammansättning av den producerade gasen undersöktes. Biogasproduktion sker i en anaerob rötningsprocess och är ett komplext förlopp där olika mikroorganismer sönderdelar substratet i flera steg för att slutligen bilda biogas samt en rötrest. Många faktorer så som substratets kemiska innehåll, temperatur och pH i rötkammaren påverkar produktionen av biogas. Analysen av metanpotential delades in i två försök. I försök 1 rötades substraten tillsammans med ymp från Växjö avloppsreningsverk vid en temperatur på cirka 37 ˚C. I försök 2 rötades substraten tillsammans med ymp från Kalmar Biogas AB vid cirka 52˚C. Båda försöken bestod av 15 stycken flaskor vardera med tre replikat för varje exmperiment: endast ymp, ymp + Alg 1 (Saccharina latissima), ymp + Alg 2 (Laminaria digitata), ymp + Papper (bioslam blandad med papperfiber) samt ymp + Referens (Cellulosa). Ymp och referenssubstratet kördes för att bedöma ympens kvalitet. Blandningar mellan ymp och substrat valdes först till 5:1 och därefter till 4:1, baserat på materialens VS-halter. Alla försök pågick tills gasproduktionen var minimal. För försök 1 med kvot 5:1 var slutresultatet av den ackumulerande metanmängden för Alg 1, Alg 2, Papper respektive Referens 315, 313, 88 respektivt 381 Nml/g VS substrat. Försöket med papper avslutades redan efter sju dagar eftersom skillnaden i metanmängd mellan flaskorna med ymp + Papper samt flaskor endast ymp var mycket liten. I försök 1 med kvot 4:1 rötades inte referenssubstratet och endast ymp främst på grund av platsbrist. Här antogs istället att endast ymp skulle ge samma resultat som i föregående försök med mesofil temperatur. Slutresultatet för försök 1 med kvot 4:1 blev 199, 214 samt 41 Nml CH4/g VS substrat för Alg 1, Alg 2 samt Papper. För försök 2 med kvoten 5:1 blev slutresultaten (den ackumulerade metanmängden) för Alg 1, Alg 2, Papper respektive Referens 191, 183, 33 respektive 243 Nml/g VS substrat. I försök 2 med kvoten 4:1 blev slutresultaten för Alg 1, Alg 2, Papper respektive Referens 288, 179, 18 respektive 337 Nml CH4/g VS substrat.

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Forkman, Tova. "Biogaspotential vid samrötningav mikroalger och blandslam från Västerås kommunala reningsverk." Thesis, Sveriges lantbruksuniversitet, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-232954.

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Because of the increasing trends in energy consumption and increased environmental awareness, greater focus has been placed on improvement and development of renewable energy sources. An already proven and accepted method is biogas production from anaerobic digestion at municipal wastewater treatment plants. In the waste water treatment process solid material and dissolved pollutants are separated from the water, forming a sludge. The sludge is separated from the process and stabilized during anaerobic digestion or aerobic aeration. Most often, mesophilic anaerobic digestion is used. Because of degradation by microorganisms, biogas with a high content of methane is formed during the digestion. To optimize the process different studies with co-digestion with sludge and other substrate have been made. It has been showed, in earlier research studies, that co-digestion with microalgae and sewage sludge results in a synergistic effect with increased biogas production. As the microalgae are microorganisms which use photosynthesis they contain stored energy from sun light. The stored energy will be available when the microalgae are digested in mesophilic conditions. In contrast to other biomass suitable for co-digestion microalgae have the advantage of being able to grow in waste water and reduce the pollutants in the water phase. Cultivation of microalgae will therefore not compete with the cultivation of food production and at the same time has the possibility to decrease the electricity- and heat consumption at the wastewater treatment plants. The aim of this study was to investigate how a possible synergetic effect between microalgae and sewage sludge effects the biogas production and the process stability. The microalgae was cultivated in municipal waste water from the WWTP in Umeå (Sweden) and the sludge was collected from the WWTP in Västerås (Sweden). The fermenters used was of the type DOLLY© and the active volume was 5 dm3. The temperature in the fermenters was kept at 37 °C and the study was divided into two periods. During the first period the hydraulic retention time was 15 days and the organic loading rate 2.4 g VS dm-3 d-1. During the second period the hydraulicretention time was kept at 10 days and the organic loading rate was 3.5 g VS dm-3 d-1. The result showed an increase with 54.6 % in methane production per reduced VS in the fermenter with co-digestion compared to the fermenter where only sludge was digested. Period one showed the highest increase. The result also showed a good process stability for both fermenters during the whole experiment. This study shows that there are reasons for continued investigations about co-digestion with microalgae and sewage sludge for an increased biogas production.
På grund av ökande el- och värmeförbrukning och ökat miljöengagemang har större fokus lagts på förbättring och utveckling av förnyelsebara källor för el- och värmeproduktion. En redan beprövad och accepterad metod för framställning av förnyelsebar energi är från biogasproduktion vid kommunala reningsverk. Vid rening av avloppsvatten avskiljs fasta partiklar och lösta föroreningar och bildar ett slam som separeras från vattnet. Slammet kan sedan stabiliseras anaerobt genom rötning eller aerobt genom luftning. En ofta använd metod vid konventionella reningsverk är mesofil anaerob rötning. Vid rötningen bryts material ner av mikroorganismer och genererar biogas som framförallt innehåller metan och koldioxid. För att optimera en sådan process och därmed kunna utvinna mer gas har det tidigare undersökts hur samrötning med olika material påverkar biogasproduktionen. Det har visat sig i forskningsförsök att samrötning med mikroalger och orötat blandslam ger en synergieffekt och mer biogas produceras. Mikroalgerna innehåller lagrad energi från solljus, då de är fotosyntesiserande organismer. Den lagrade energin har visat sig bli tillgänglig vid mesofil anaerob nedbrytning. Till skillnad från annan biomassa som undersökts för samrötning kan mikroalgerna odlas på avloppsreningsverken och fungera som en del av reningsprocessen då mikroalgerna tar upp näringsämnen ur vattnet de växer i. På det sättet undviks konkurrens om odlingsmark för livsmedel och så blir reningsprocessen på avloppsreningsverken mer el- och värmeeffektiv. Syftet med studien var att undersöka om eventuell synergieffekt mellan mikroalgerna och slammet påverkar biogasproduktionen och processtabiliteten vid mesofil anaerob rötning. Mikroalgerna som användes var odlade på mekaniskt renat spillvatten från Umeås reningsverk och slammet som användes hämtades ifrån Västerås reningsverk. Rötkamrarna som användes var av modellen DOLLY© med en aktiv volym på 5 dm3. Temperaturen i rötkamrarna hölls kring 37°C och studien var uppdelad i två perioder. Under period ett var den hydrauliska uppehållstiden 15 dygn och den organiska belastningen 2,4 g VS dm-3 d-1, medan period två hade en hydraulisk uppehållstid på 10 dygn och en organisk belastning på 3,5 g VS dm-3 d-1. Resultaten visade att metangasproduktionen per tillförd mängd organiskt material var lägre vid samrötning jämfört med rötning av enbart slam. Metangasproduktionen per reducerad mängd organiskt material ökade med upp till 54,6 % vid samrötningen jämfört med rötning av enbart slam. Period ett gav upphov till den största ökningen. Processen hölls stabil även vid inblandning av mikroalger, under både period ett och två. Studien visar att det finns ett underlag för fortsatta studier kring samrötning av mikroalger och slam för en ökad biogasproduktion.

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Backlund, Sofia. "Avsättningsalternativ för avloppsslam utifrån effektiviserad slambehandlingsmetod i Avesta kommun : med fokus på hygienisering och miljömässig nytta." Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-19947.

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Avloppsslam innehåller näringsämnen, som bör återföras till naturen för att skapa ett så kallat näringskretslopp. Genom att optimera hygieniseringen av avloppsslam med effektivare behandlingsmetod kan avloppsslam bli mer lämpligt att avsättas ur ett bättre ekonomiskt- och miljömässigt perspektiv. Syftet med arbetet var att undersöka och bedöma om effektiviseringav befintlig slambehandling är möjlig för att uppnå tillräcklig hygienisering. Utifrån den effektiviserade slambehandlingsmetoden utreda möjliga avsättningsalternativ som lämpar sig bäst för avloppsslammet i Avesta kommun. En litteraturöversikt utfördes för att öka kunskapen och förståelsen av avloppsslam, desshantering och avsättning. Fallstudien är utformad med kvalitativ metod och informationen har inhämtats från vetenskapliga artiklar, myndigheter, rapporter, examensarbeten och personligkontakt som komplement för att erhålla en god förståelse. Uppgradering av mesofil rötning av avloppsslam vid 37 °C till termofil rötning, 55 °C – 65 °C innebär förhöjd temperatur; det kräver mer energi och ökade energikostnader. Komponenter av den mesofila rötningsprocessen kommer att behöva uppgraderas eller bytas ut och därför tillkommer extra kostnader som också behöver ses över. Fördelarna med termofil rötning inkluderar kortvariga uppehållstider, mindre rötkammare och slammet blir tillräckligt hygieniserat. Ett framtidsscenario är framtaget utifrån effektiviserad slambehandling där två avsättningsalternativ är mest lämpliga för avloppsslammet i Avesta kommun. Gödsel till produktiv mark är ett av de föreslagna alternativ som tillåter fosforn återvinnas och återanvändas. Om inte termofil rötning som effektivisering hade erhållit tillräcklig hygienisering borde andra komplementerande processer ha införts, exempelvis komposteringstrumma eller pastörisering. En fullständig kostnadsjämförelse mellan befintlig slambehandlingsmetod och mer effektiviserad slambehandlingsmetod är dock nästan omöjlig att utföra då alla kostnader beror på val av komponenter och faktorer. Denna fallstudie bidrar med ett underlag som kan ge större möjligheter för Avesta Vatten och Avfall AB att välja den mest lämpliga avsättningen för avloppsslammet i Avesta kommun i framtiden.
Sewage sludge contains nutrients, which should be returned to nature to create a so-called nutrient circulation. By optimizing sanitisation of sewage sludge with effective treatment methods, sewage sludge can be more appropriately disposed from a better economic- and environmental perspective. The aim of this work was to investigate and judge the efficiency of existing sludge treatment is possible to achieve a sufficent sanitation. Based on the streamlined sludge treatment method investigate the disposal options that is best suited for sewage sludge in Avesta town. A literature review was conducted to increase the knowledge and understanding of sewage sludge, its treatment and disposal. The case study is formed with qualitative method and information which has been collected from the scientific articles, authorities, reports, theses and personal contact as a complement to obtain a good understanding. Upgrading of mesophilic digestion of sludge at 37 ° C to thermophilic digestion at 55 ° C - 65 ° C means increased temperature; this requires more energy and hence increases energy costs. Components of the mesophilic digestion process need to be upgraded or replaced and therefore additional costs should also be considered. The advantages of the thermophilic digestion include short residence time, smaller digester and sludge becomes sufficiently disinfected. A future scenario is developed based on more efficient sludge treatment where two disposal options are most appropriate for the sewage sludge in Avesta town. Returning digestate to productive land is one of those suggested alternatives that allows phosphorus to be recovered and recycled. If not thermophilic digestion as streamlining is not effective enough for sufficient sludge sanitation, other complementary processes have to be introduced, for instance, composting drum or pasteurization. A full cost comparison between the existing sludge treatment and more efficient sludge treatment method is, however, almost impossible to be performed when all costs depend on the choice of components, factors and so on. This case study contributes with first-hand information that can provide greater opportunities for Avesta Vatten och Avfall AB to select the most appropriate options for sewage sludge disposal in Avesta town in the future.

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Sylla, Ibrahima. "high loaded anaerobic mesophilic digestion of sewage sludge : An evaluation of the critical organic loading rate and hydraulic retention time for the anaerobic digestion process at Käppala Wastewater Treatment Plant (WWTP)." Thesis, Mälardalens högskola, Framtidens energi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-52406.

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Käppala wastewater treatment plant (WWTP) has, during a few years, observed an increase in organic loading rate (OLR) in the mesophilic anaerobic digester R100, due to an increased load to the WWTP. The digestion of primary sludge at Käppala WWTP is today high loaded, with a high organic loading rate (OLR) and low hydraulic retention time (HRT). This study aims to evaluate the effect of the maximum OLR and the minimum HRT for the anaerobic digestion of sewage sludge and to investigate further actions that can be taken into consideration in case of process problems in the digestion. The study consists of (a) a practical laboratory experiment of 6 pilot-scale reactors to investigate how the process stability is affected when the OLR increases and the HRT decreases. (b) A mass balance calculation based on the energy potential in the feeding sludge and the digested sludge. (c) A study of the filterability of the digested sludge. (d) The construction of a forecasting model in Excel, to predict when digester R100 will reach its maximum OLR and minimum HRT. The result of the study shows that the maximum OLR for Käppala conditions is 4.9 g VS dm-3 d-1, meaning that R100 will reach its maximum organic load around the year 2031. An OLR of 4.5-4.9 and an HRT of 12 days is optimal for R100, according to the present study. Keeping the anaerobic digestion process in balance is vital when it comes to the outcome of energy in the anaerobic digestion process. Pushing the process to produce more gas can become counterproductive since a high OLR can lead to process imbalance, which in turn leads to low biogas production. Imbalance in the digestion process can occur fast; therefore, the margin for overload in the anaerobic digestion process must be significant. The methane concentration in the converted biogas and the pH level in the reactor are the best stability parameters for the conditions at Käppala. Ammonia is the less efficient stability parameter since it did not predict or detect any instability during the experimental process. Furthermore, the OLR and HRT have a significant impact on the needed quantity for dewatering polymer. The higher digestion of organic material in the sludge, the bigger the need for the polymer to take care of the rest material.

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Gärdeklint, Sylla Ibrahima Sory. "HIGH LOADED ANAEROBIC MESOPHILIC DIGESTION OF SEWAGE SLUDGE : An evaluation of the critical organic loading rate and hydraulic retention time for the anaerobic digestion process at Käppala Wastewater Treatment Plant (WWTP)." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-52283.

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Käppala wastewater treatment plant (WWTP) has, during a few years, observed an increase in organic loading rate (OLR) in the mesophilic anaerobic digester R100, due to an increased load to the WWTP. The digestion of primary sludge at Käppala WWTP is today high loaded, with a high organic loading rate (OLR) and low hydraulic retention time (HRT). This study aims to evaluate the effect of the maximum OLR and the minimum HRT for the anaerobic digestion of sewage sludge and to investigate further actions that can be taken into consideration in case of process problems in the digestion. The study consists of (a) a practical laboratory experiment of 6 pilot-scale reactors to investigate how the process stability is affected when the OLR increases and the HRT decreases. (b) A mass balance calculation based on the energy potential in the feeding sludge and the digested sludge. (c) A study of the filterability of the digested sludge. (d) The construction of a forecasting model in Excel, to predict when digester R100 will reach its maximum OLR and minimum HRT. The result of the study shows that the maximum OLR for Käppala conditions is 4.9 g VS dm-3 d-1, meaning that R100 will reach its maximum organic load around the year 2031. An OLR of 4.5-4.9 and an HRT of 12 days is optimal for R100, according to the present study. Keeping the anaerobic digestion process in balance is vital when it comes to the outcome of energy in the anaerobic digestion process. Pushing the process to produce more gas can become counterproductive since a high OLR can lead to process imbalance, which in turn leads to low biogas production. Imbalance in the digestion process can occur fast; therefore, the margin for overload in the anaerobic digestion process must be significant. The methane concentration in the converted biogas and the pH level in the reactor are the best stability parameters for the conditions at Käppala. Ammonia is the less efficient stability parameter since it did not predict or detect any instability during the experimental process. Furthermore, the OLR and HRT have a significant impact on the needed quantity for dewatering polymer. The higher digestion of organic material in the sludge, the bigger the need for the polymer to take care of the rest material.

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Walkey, Helen Clare. "Visual performance in the mesopic range." Thesis, City University London, 2003. http://openaccess.city.ac.uk/7609/.

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The aims of this work were to assess the effects of different stimulus parameters on chromatic sensitivity, with particular emphasis on the effect of retinal illumination, and to investigate aspects of suprathreshold visual performance under mesopic conditions. All investigations were performed using visual psychophysical techniques. Chromatic thresholds were obtained using dynamic luminance contrast noise to isolate responses to colour signals. The effects of stimulus size and spatial distribution were examined in normal trichromats, dichromats and subjects with acquired colour vision deficiency. The chromatic sensitivity of normal trichromats was investigated with reduction in light level. Measurements were also performed to assess the possible involvement of rods in chromatic processing at threshold. Suprathreshold performance in the mesopic range was assessed in terms of the relative contributions of colour and luminance contrast to a measure of stimulus conspicuity and to visual search time. The conspicuity of a stimulus defined by colour and luminance contrast was defined as the value of achromatic contrast of a similar stimulus with an equal perceived conspicuity. An empirical model was developed from an extensive data set of conspicuity matches, to enable prediction of conspicuity for a wide range of coloured stimuli. Visual search performance for both achromatic and coloured stimuli was investigated under mesopic conditions, and results for the coloured stimuli were compared to the measure of stimulus conspiculty combined with an achromatic search time calibration. The results revealed that chromatic sensitivity is dependent on stimulus size, spatial distribution, eccentricity of presentation and level of illumination. These factors are suggested to reflect changes in cone performance and the relative cone contributions to the postreceptoral chromatic channels. Chromatic sensitivity was found to be independent of rod activity in the mesopic range, suggesting separate processing of rod signals and threshold colour signals under mesopic conditions. Measurements of stimulus conspicuity under mesopic conditions revealed individual variations in response to both luminance contrast and chromatic signals indicative of individual differences in gain control of postreceptoral mechanisms. Conspicuity was successfully modelled as a function of photopic contrast, scotopic contrast, chromatic difference to the background and the level of illumination. The nonlinear relationship between search time and luminance contrast was found to change with reduction in light level, reflecting increased contrast thresholds and diminishing effectiveness of unit physical contrast. Mesopic visual search was also found to depend on the photopic contrast, scotopic contrast and chromatic content of the stimulus, but with an apparent greater emphasis on scotopic contrast and reduced emphasis on colour compared to the measure of stimulus conspicuity. Conspicuity was successfully used to predict visual search times, and was found to be an improved indicator of search performance than either photopic or scotopic contrast.

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Kvasnikova, Ioulia. "Mesonic sources of dileptons in ultrarelativistic nuclear collisions." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=37753.

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In this work thermal dilepton production from a hot medium created in heavy ion collision is studied. Using an effective Lagrangian technique for particle decays and annihilations, a complete method for calculation of the lepton pair production rate is developed. The importance of axial vector meson contributions to the dilepton spectrum is analyzed. Different effective Lagrangians for the a1rhopi interaction are considered, and a new form of b1o(&phis;)pi effective Lagrangian is introduced.
A systematic study of light meson contributions is performed. The most significant decay and reaction contributions are calculated and summed for low and intermediate invariant mass dileptons. The calculated dilepton rate is compared to that obtained using spectral functions extracted from data, and it is shown that the chosen set of mesonic reactions and decays accounts for all significant contributions to the thermal dilepton emission.
A hydrodynamic approach to the space-time evolution of the hot medium formed as a result of a central heavy ion collision at ultra-relativistic energies is considered. A theoretical curve of intermediate invariant mass dilepton spectrum is computed and compared to the NA50 data from central Pb(158 AGeV)+Pb collisions. Experimental acceptance cuts are accounted for. Drell-Yan processes are considered as well. We find that our thermal dileptons account for the intermediate mass excess observed by the NA50 Collaboration. We see no need to invoke charm enhancement. Predictions for the future experiments at RHIC and are made.

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Ebertshäuser, Thomas. "Mesonic chiral perturbation theory odd intrinsic parity sector /." [S.l.] : [s.n.], 2001. http://ArchiMeD.uni-mainz.de/pub/2002/0020/diss.pdf.

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Walker, Grace. "Investigation of visual performance at mesopic light levels." Thesis, City University London, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.554384.

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This thesis describes results of experimental studies designed to investigate some functional aspects of visual performance in the mesopic range. The principal part of the study involved extensive measurements of contrast-acu- ity thresholds in a large number of subjects, age range: 17 to 61 years. The tests were carried out at high mesopic levels of light adaptation and provided the basis for establishing the statistical limits for normal subjects. Further studies were carried out to attempt to explain the differences between pho- topic and mesopic conditions and the increased intersubject variability mea- sured at mesopic light levels. These studies examined the extent to whic higher-order optical aberrations at larger pupil sizes, macular pigment opti- cal densities and susceptibility to increased crowding in the mesopic range are potential sources of the variability. Other aspects of visual performance have also been examined, such as sensitivity to red-green and blue-yellow colour differences measured at mesopic light levels of retinal adaptation and the effects that selective absorption by the lens and macular pigment may have on chromatic sensitivity. Results revealed much increased variability in contrast acuity thresholds-at mesopic light levels when compared to the results measured in the photopic range. Around 50% of the subjects achieved mesopic contrast acuity thresh- olds comparable to those measured for the whole population in the photopic range. 11.2% and 12.6% of the variance in contrast thresholds at the fovea and parafovea were due to increased higher-order aberrations. Age made a sig- nificant contribution accounting for 18% of the measured variability. Neither peak macular pigment optical density nor average macular pigment optical density (over the centre ±2.8°) were found to have a significant difference on contrast acuity thresholds when comparing the extremes of the distribution. Susceptibility to crowding was also not significant suggesting that the effects of visual crowding do not increase significantly when contrast acuity is mea- sured in the mesopic range. Colour thresholds showed no significant corre- lation with either lens absorption or selective absorption of short wavelength light by the macular pigment.

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Pérez-Obiol, Castañeda Axel. "Non-mesonic weak decay of hypernuclei in effective field theory." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/144554.

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In this thesis we have described the weak Lambda N to NN interaction, which is the main responsible for the decay of heavy hypernuclei, within the effective field theory (EFT) framework. The EFT is developed up to second order in “q”, where “q” is the transferred momentum between the interacting baryons. In particular, all the two-pion exchange diagrams entering at second order in the momentum expansion have been calculated. Numerical values for the leading order low-energy constants are obtained by two means. First, a fit to the hypernuclear decay observables for three light hypernuclei, 5-Lambda/He, 11-lLambda/B i 12/Lambda/C, has been performed. This calculation has involved a proper description of the initial and final nuclear states within a many-body formalism. Second, the EFT has been compared to the one-meson-exchange model describing the same interaction. By expanding the one-meson-exchange potentials in powers of momentum, the low energy constants appearing in the EFT description have been written in terms of the heavy meson parameters. In order to obtain a less model dependent description of the weak decay of hypernuclei we have studied the decay of the lightest hypernucleus, the hypertriton, which can be described within an effective field theory framework in both the strong and the weak sectors.
En aquesta tesi hem descrit la interacció feble LambdaN->NN, la qual és la principal responsable de la desintegració d’hipernuclis pesats, en el marc de teories efectives de camps. La teoria efectiva de camps (EFT) s’ha desenvolupat fins a segon ordre en “q”, on “q” és el moment transferit entre els barions interactuants. En particular s’han calculat tots els diagrames d’intercanvi de dos pions que apareixen al segon ordre en l’expansió de moments. Els valors numèrics de les constants de baixa energia s’han obtingut de dues maneres. Primer,s’ha fet un ajust als observables de desintegració hipernuclear per a tres hipernuclis lleugers, 5-lambda/He,11-lambda/B i 12-lambda/C. Per una banda, aquest càlcul ha involucrat la EFT a primer ordre per a la transició feble LambdaN->NN, i per l’altra, una descripció adequada dels estats nuclears inicials i finals en un formalisme de molts cossos. Segon, la EFT s’ha comparat al model d’intercanvi d’un mesó que descriu la mateixa interacció. Expandint els potencials d’intercanvi d’un mesó en potències de moment, les constants de baixa energia que apareixen en la EFT s’han escrit en termes dels paràmetres dels mesons pesats. Per tal d’obtenir una descripció de la desintegració feble d’hipernuclis menys depenent de model s’ha estudiat la desintegració de l’hipernucli més lleuger, l’hipertritó, el qual pot ser descrit en el marc de teoria efectiva de camps tan en el sector feble com en el sector fort. En aquest cas, les constants de baixa energia no s’han pogut ajustar a observables hipernuclears degut a la manca de dades experimentals per a la desintegració feble de l’hipertritó. Alternativament, s’ha estudiat com el ritme de la desintegració feble de l’hipertritó depèn de les constants de baixa energia de primer ordre.

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Monteiro, Jose Roberto Borges. "Composição floristica e estrutura de uma floresta mesofila semidecidua no municipio de Chapada dos Guimarães, MT." [s.n.], 1993. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315115.

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Orientador: Hermogenes de Freitas Leitão Filho
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-07-18T11:53:42Z (GMT). No. of bitstreams: 1 Monteiro_JoseRobertoBorges_M.pdf: 3187606 bytes, checksum: 10e33cb30f66825f5563e8904951f245 (MD5) Previous issue date: 1993
Resumo: O estudo foi desenvolvido em uma floresta mesófila semidecídua, na Fazenda 20 de dezembro em Chapada dos Guimarães, Mato Grosso ('15 GRAUS¿ 17' de latitude e ¿55 GRAUS¿ 48' de longitude). O solo é do tipo Latossolo Vermelho-Amarelo, argiloso a argilo-arenoso coberto por fina camada de cascalho de sesquióxido de ferro. Foram amostrados todos os indivíduos lenhosos (exceto lianas) com 15 ou mais cm de circunferência à altura do peito (C.A.P.), em duas áreas de 5.000 m2 subdividida em unidades amostrais de 100 m2 (10 X 10 m) num total de 10.000 m2 (lha). Amostrou-se 1429 indivíduos, dos quais 69 mortos, distribuídos por 43 famílias, 81 gêneros e 98 espécies (sendo 03 desconhecidas a nível genérico e 05 a nível específico). O índice de diversidade de SHANNON-WEAVER para espécies foi 3,61 para a área 1 e 3,79 para a área 2, valor semelhante ao encontrado em florestas mesófilas semidecíduas do Estado de São Paulo ... Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital
Abstract: The research was developed in one mesotropic semidecious forest, on the Farm 20 de dezembro in Chapada dos Guimarães, Mato Grosso State (15 DEGREES 17¿ lat. and ¿55 DEGREES 48¿ log.) The soil type is Latossolo-red-yellow, clay-sandness covered for thin layer of rubble from sesquioxide of iron. We sampled all of the wood individuals (except lianas) with 15 em or more of breast high eireunferenee (B.H.C.) in two areas of 5.000 m2 subdivided on sample units of 100 m2 (10 X 10m) in a total of 10.000 m2. It was sampled 1.429 individuals, from wieh 69 died, shared for 43 families, 81 genera and 98 speeie (being 3 unknown for generie level and 5 for speeifie level). The diversity index of SHANNON-WEAVER for speeie was 3,61 for the area 1 and 3,79 for the area 2, the same value was founded in forests from São Paulo State ... Note: The complete abstract is available with the full electronic digital thesis or dissertations
Mestrado
Biologia Vegetal
Mestre em Ciências Biológicas

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Figueiredo, Nivaldo de. "Estudo fitossociologico em uma floresta mesofila semidecidua secundaria na Estação Experimental de Angatuba, municipio de Angatuba, SP." [s.n.], 1993. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315438.

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Orientador : Neusa Taroda Ranga
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Este trabalho foi realizado em uma área de floresta Mesófila Semidecidua secundária da Estação Experimental de Angatuba, município de Angatuba ¿ SP (48º15a 48º25'W e 23º30'S). Localizada sobre um braço de serra, apresenta altitudes variando de 608 a 817m. O clima é Cwa de Koeppen ¿ tropical, quente, de inverno seco não rigoroso, com temperatura média anual de 19ºC e precipitação média anual (coletada de 1964 a 1986) de 1321mm. O balanço hídrico e climático, para 125mm de capacidade de armazenamento no solo, registrou um excedente hídrico de 418mm, não havendo deficiência hídrica no solo no período analisado (considerando os valores médios). Os solos rasos com afloramentos rochosos em vários pontos parecem enquadrar-se como Litólicos, embora um estudo de perfil não tenha sido efetuado. As análises químicas revelaram um solo ácido, distrofico, com elevado teor de matéria orgânica nas camadas superficiais na maioria das parcelas, sugerindo que a ciclagem de nutrientes desempenha um papel fundamental na manutenção daquele sistema. A vegetação foi amostrada através da instalação sistemática de 50 parcelas de 10m X 10m, sendo coletado, também, através de caminhadas aleatórias, as espécies que ocorreram fora das parcelas. Foram amostrados 1078 indivíduos de 48 famílias e 128 espécies, com pelo menos 4,78cm de DAP. Deixaram de ser amostradas (coletadas fora das parcelas), 51 espécies e 10 família... Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital
Abstract: A fitossociological study was carried out a secondary Forest area in the ¿Estação Ecologica de Angatuba¿ of ¿Instituto Florestal¿, municipality of Angatuba, State of São Paulo (48º15' to 48º25'W and 23º30'S), and southeastern Brazil. The sampling area is situated on a branch of Angatuba Hill with altitudes between 608m and 817m; the climate was classified as Koeppen's Cwa ¿ tropical, warm, with a non-rigorous dry winter. The annual mean temperature was 19ºC. the annual mean rainfall collected from 1964 to 1986 was 1321 mm. The water and climatic balance showed a 418 mm water excess and absence of water deficit during the analised period, considering the average values. The shallow soil with rock outcrops in several sampling points seems to allow its classification as Litolic, although a profile study was lacking. The chemical analysis showed that the soil is acid, distrophic with high level of organic matter in surface layers of most samples, suggesting that the cycles of nutrients play a fundamental role for the maintenance of this system. The vegetation was sampled by fifty 10m X10m plots laid out on a regular grid. Besides, outside the plots, additional collection were made throughout the ¿Estação¿ by random hikes. One hundred seventy eight individuals were sampled, belonging to 48 families and 128 species, with at least 4,78 cm DBH. Fifty one species and 10 families were collected outside the plots... Note: The complete abstract is available with the full electronic digital thesis or dissertations
Mestrado
Biologia Vegetal
Mestre em Ciências Biológicas

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Ribeiro, Tulio Alberton. "Mesobi: memória transacional em software tolerante a faltas bizantinas." reponame:Repositório Institucional da UFSC, 2015. https://repositorio.ufsc.br/xmlui/handle/123456789/136337.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Ciência da Computação, Florianópolis, 2015.
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Memória Transacional em Software (STM) é um modelo utilizado para tratar acesso concorrente a dados compartilhados, onde programadores não precisam lidar explicitamente com mecanismos de controle de concorrência, como locks. O programador, apenas delineia qual parte do código necessita ser tratado como concorrente e sua execução seguirá o modelo transacional, respeitando as propriedades: atomicidade, consistência e isolação. É proposto nessa dissertação um modelo denominado Mesobi: Memória Transacional em Software Tolerante a Faltas Bizantinas onde transações somente leitura não abortam. Existem algumas abordagens na literatura que utilizam Memória Transacional em Software, das quais grande parte tolera faltas de parada mas pouco se fala sobre faltas maliciosas. Somente o trabalho de Zhang 2012 faz tolerância a faltas Bizantinas no contexto de STM; sua proposta utiliza dois clusters para alcançar tolerância a faltas Bizantinas.No modelo de Zhang, transações somente leitura podem ser abortadas, não é suportada a execução de transações interativas e não é possível executar transações de forma otimista. O Mesobi permite alcançar tolerância a faltas Bizantinas utilizando (3f+1) réplicas, sendo que, f é o número de faltas toleradas. O modelo consiste em inicialmente tentar executar as transações de forma otimista sem a necessidade de executar o protocolo Bizantino. Transações conflitantes localmente não são iniciadas de imediato com isso evita-se trabalho improdutivo. É possível e viável a execução de transações pré-declaradas e interativas no mesmo ambiente, sendo que, transações interativas têm pior desempenho devido a sua maior troca de mensagens.

Abstract : Software Transactional Memory (STM) is a model to deal concurrent accesses on shared data. With STM developers do not need to cope with explicit concurrency control mechanisms like locks. Instead developers can write parallel portions of code as transactions, which are garanteed to execute atomically and in isolation regardless of eventual data races. In this dissertation we propose a model named Mesobi: Memória Transacional em Software Tolerante a Faltas Bizantinas in which read-only transactions do not abort. There are some approaches in literature that use STM, but most of them treat crash faults, but few deal with arbitrary faults. The work presented by Zhang 2012 mentions Byzantine Fault Tolerance (BFT) in STM context, but two clusters are necessary, one for consensus and another to execute transactions. Zhang's model abort read-only transactions, does not use optimistic execution neither interactive transactions processing. It achieves BFT using (3f+1) replicas where f represents the number of tolerated faults. The model executes in an optimistic fashion the transactions without the BFT protocol. Conflicting local transactions are not executed immediately thereby saving wasted work. Execution and consistency tests showed that execution of interactive and pre-declared transactions on same environment are possible and practical. Interactive transactions have worse performance than pre-declared due to need of more message exchanges.

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Barros, Kallyne Ambrósio. "Papel do transportador vacuolar de malato e sua função no mesofilo: uma relação estreita com o metabolismo primário." Universidade Federal de Viçosa, 2015. http://www.locus.ufv.br/handle/123456789/8358.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Diversos mecanismos foram aprimorados durante a evolução das plantas de modo a se obter uma resposta adequada às variações ambientais, principalmente no que respeita os mecanismos relacionados ao controle dos movimentos estomáticos. Nesse contexto, o vacúolo parece exercer um papel preponderante na tolerância a vários estresses em função da sua plasticidade em acumular solutos para manutenção do turgor e integridade celular ou mesmo para estabilizar compostos tóxicos. Dada a relevância dos estômatos para a fixação de CO2, adicionada à atuação dos ácidos orgânicos no controle dos movimentos estomáticos e o papel do vacúolo como acumulador de solutos, este trabalho buscou investigar como a perda funcional do transportador vacuolar de malato (AttDT) impacta Arabidopsis thaliana, de modo a caracterizá-las e entender como o transportador, em conjunto com ácidos orgânicos, afetam o metabolismo primário e os movimentos estomáticos. Reduções nas taxas fotossintéticas associadas com menores condutâncias estomática e mesofílica foram observadas em mutantes attdt. Entretanto, incrementos nas taxas respiratórias, sem alteração nos níveis totais de clorofilas, açúcares, proteínas e aminoácidos foram observados. De modo a suprir a demanda energética e assim garantiar a manutenção do crescimento, como observado em plantas attdt, substratos alternativos parecem estar sendo utilizados, culminando com um funcionamento não cíclico do ciclo dos ácidos tricarboxilicos (TCA), visto que succinato, fumarato e malato foram reduzidos ao passo que incrementos nos níveis de citrato, simultaneamente à alterações no perfil de aminoácidos, especialmente aspartato e glutamina, foram evidentes. Embora o crescimento não tenha sido drasticamente afetado, cumpre mencionar que plantas com perda do transportador AttDT apresentam fenótipo metabólico que se assemelham grandemente ao de plantas sob estresse, principalmente por seca. Coletivamente, os resultados obtidos indicam que AttDT é um transportador de fundamental importância para manutenção dos níveis adequados de ácidos orgânicos entre os compartimentos celulares, e que a sua perda funcional ocasiona uma reprogramação metabólica e afeta diretamente o metabolismo primário, especialmente a respiração e o catabolismo de aminoácidos.
Several mechanisms were improved during the course of plant evolution to obtain an adequate response to environmental variations, particularly mechanisms related to the control of stomatal movements. Accordingly, the vacuole seems to play an important role in plant stress tolerance, due to its plasticity to accumulate solutes maintaining both cell integrity and turgor or further stabilizing toxic compounds. Given the pivotal importance of stomata to CO2 fixation, in addition to the role of organic acids in controlling stomatal movements coupled with the key role of vacuole in the accumulation of solutes, this study investigated the functional role of the vacuolar malate transporter, AttDT, in order to characterize and understand how the absence of this carrier, together with organic acids, affect both the primary metabolism and stomatal movements. Reductions of photosynthesis rates coupled with decrease on both mesophilic and stomatal conductance were observed in mutant attdt. However, enhanced respiratory rates without impacting the total levels of chlorophyll, sugars, proteins and amino acids were observed. In order to supply the energy demand to maintain growth that was not altered in attdt plants, it seems that alternative substrates are used. This is likely leading to a non-cyclic function of the TCA cycle, as succinate, malate and fumarate were reduced whereas increase of citrate levels was observed, simultaneously to changes in the amino acid profile, especially aspartate and glutamine. Interestingly, plants lacking AttDT display a metabolic phenotype that resembles that of plants under stress, mainly drought, although growth has not been affected. Taken together, the results obtained here indicates that AttDT is an important carrier allowing the maintainance of suitable levels of organic acids between cellular compartments, directly affecting the primary metabolism, especially respiration and amino acids.

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De, Jesús Hernandez Gerardo Daniel. "Determinación de Mesofilos Aerobios, Coliformes Totales y Coliformes Fecales en el cultivo de cilantro ( Coriandrum sativum L.), producido en tres municipios del Estado de México." Tesis de Licenciatura, Universidad Autónoma del Estado de México, 2016. http://hdl.handle.net/20.500.11799/65576.

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El objetivo de la presente investigación fue determinar la contaminación de origen microbiológico del cultivo de cilantro (Coriandrum sativum L.) que se produce en tres municipios del Estado de México, durante los ciclos de producción 2014-2015, con el fin de conocer los posibles riesgos a la salud y así aplicar estrategias de prevención previo a su consumo. Se realizó un análisis microbiológico de muestras de cilantro, para determinar los microorganismos patógenos presentes en el cultivo que afectan la calidad del producto, provocando enfermedades gastrointestinales a los consumidores. Así mismo, se analizó el suelo y el agua de riego para determinar la principal fuente de contaminación. Para la determinación de microorganismos patógenos presentes en las muestras se utilizaron las metodologías marcadas en las Normas Oficiales Mexicanas NOM-092-SSA1-1994, NOM-109-SSA1-1994, NOM-110-SSA1-1994 y NOM-113-SSA1-1994. Los resultados obtenidos indicaron la presencia de microorganismos patógenos, que afectan la calidad microbiológica del producto, para los Mesófilos Aerobios, estos se encuentran dentro de los parámetros permitidos por la NOM-092-SSA1-1994. Similarmente los análisis realizados para determinar Coliformes Totales y Fecales, indicaron un nivel elevado de microorganismos de Coliformes Totales, sin embargo, se encontró la presencia de Coliformes Fecales estos no sobrepasan los límites establecidos por la NOM-113-SSA1-1994; estos microorganismos indican la presencia de materia fecal en el alimento o bien una mala realización de prácticas inadecuadas de higiene, ambas pueden ser responsables de ocasionar enfermedades gastrointestinales en el consumidor, si el producto se consume sin recibir algún tratamiento como puede ser el lavado y desinfestado. Los resultados de las muestras de suelo y agua arrojan la presencia de Coliformes Fecales y elevadas cantidades de Mesófilos Aerobios.
Universidad Autónoma del Estado de México; Facultad de Ciencias Agrícolas. Proyecto: Calidad microbiologica de tres hortalizas producidas en el Estado de México. con clave:3791/2014/CID

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Ramirez, Cruz Katia Anahi. "Determinación de Mesofilos Aerobios, Coliformes Totales y Coliformes Fecales en el cultivo de espinaca ( Spinacia oleraceaL.), producido en tres municipios del Estado de México." Tesis de Licenciatura, Universidad Autónoma del Estado de México, 2017. http://hdl.handle.net/20.500.11799/65584.

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El objetivo de esta investigación fue determinar la contaminación de origen microbiológico en el cultivo de espinaca, producida en tres Municipios del Estado de México mediante la identificación de Mesófilos Aerobios, Coliformes Totales y Coliformes Fecales con el fin de conocer la calidad del producto y que a su vez podamos conocer los posibles riesgos que puedan provocar enfermedades al consumidor y así poder aplicar estrategias preventivas antes de su consumo, así mismo se analizaron muestras de agua de riego y suelo para poder determinar las posibles causas de contaminación del cultivo de la espinaca. Para la determinación de microorganismos patógenos presentes en las muestras se utilizaron las metodologías señaladas por las Normas Oficiales Mexicanas viii NOM-092-SSA1-1994, NOM-109-SSA1-1994, NOM-110-SSA1-1994 y NOM-113-SSA1-1994. En los resultados obtenidos de las muestras indican la presencia de microrganismos capases de afectar la calidad del producto, para Mesófilos Aerobios no sobrepasan los límites permitidos por la NOM-092-SSA1-1994, mientras tanto para Coliformes Totales y Coliformes Fecales en el cultivo de espinaca se encontró el grado de contaminación de dichas variables está por debajo de los límites máximos permitidos por las NOM-113-SSA1-1994, al encontrar la presencia de estos microorganismos nos indica el grado de contaminación por materia fecal en el cultivo y la mala aplicación de prácticas de higiene por parte de los trabajadores ya que estas pueden ser las responsables de ocasionar enfermedades a los consumidores. Para los resultados de suelo y agua de riego analizados arrojaron elevadas cantidades de contaminación de microorganismos mesófilos aerobios y coliformes fecales, sin embargo no existe norma que indique el límite máximo permitido por dichos microorganismos.
Universidad Autónoma del Estado de México, Facultad de Ciencias Agrícolas. Proyecto: Calidad Microbiologica de tres hortalizas producidas en el Estado de México. clave: 3791/2014/CID

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Zartova, Irina. "Mesonic fusion - pion and eta meson production in light ion nuclear fusion reactions." Doctoral thesis, Stockholms universitet, Fysikum, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-39875.

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The present thesis describes two experiments performed in the storage ring CELSIUS at The Svedberg Laboratory in Uppsala. In the first experiment the importance of three - nucleon clustering in the six - nucelon system was investigated. The total cross section for the production of the ground state and the 3.56 MeV second excited state of 6Li in the 3He(3He,6Li)π+ reaction has been measured at two beam energies, 261.1 and 262.5 MeV, corresponding to center - of - mass energies 1.2 and 1.9 MeV above the production threshold for the 3.56 MeV state. For the ground state the result was 347 ± 84 ± 42 and 92 ± 84 ± 11 nb respectively. The result for the 3.56 MeV state, 104 ± 23 ± 12 and 56 ± 35 ± 7 nb respectively, is compared to the result of a previous study where the 3.56 MeV state was populated in the d(4He,6Li)π0 reaction. In the second experiment a clean sample of 5×105 eta mesons was prepared by means of the d(p,3He)η reaction. Eta production was tagged by the precise determination of the kinetic energy of the associated 3He ions. In the subsequent decay of eta mesons, channels with lepton - anti - lepton pairs were studied in the WASA detector. In a separate study properties of the WASA deuterium pellet target were investigated and in particular the effects on the beam of the beam - target interactions. In both sets of experiments the fused nuclear system was detected by means of a zero - degree spectrometer with a semiconductor detector telescope. Choosing the detectors to match the rather different requirements, precise information regarding the identity and the momentum of the detected ions could be obtained in both cases.

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Trottier, Olivier. "The vector mesonic spectrum of a large N QCD model in string theory." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121393.

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Following the holographic QCD model of Sakai and Sugimoto, we analyze the mesonic spectrum of a large N thermal QCD model in the dual string theory. After a T-dual transformation, the background of the ten-dimensional spacetime contains N D4-branes and $N_f$ D6/D6-branes and the internal manifold consists of a resolved-deformed conifold whose $\psi$ direction is the analogue of the compact cycle of the Sakai-Sugimoto's geometry. Using the probe approximation, we study the DBI action of the D6-branes and, by restricting the coordinate dependence of the ten-dimensional gauge flux components $A_M$, we recover a four-dimensional QCD-like action. In particular, this reduced action contains mass terms of vector mesons, which are related to the Minkowski components of the gauge flux. We calculate the values of these masses and our predictions find good agreement with the experimental values.
Inspiré par le modèle de mécanique chromodynamique (QCD) holographique de Sakai et Sugimoto, nous analysons, dans la limite où N est grand, le spectre mésonique d'un modèle de QCD à température finie à partir de la théorie des cordes correspondante. Après une transformation de dualité T, l'espace-temps de dix dimensions contient N D4-branes et $N_f$ D6/D6-branes et les dimensions enroulées consistent en une variété conique dont la dimension $\psi$ est l'analogue de la dimension enroulée de la géométrie de Sakai-Sugimoto. En utilisant l'approximation de sonde, nous étudions l'action DBI des D6-branes et, en restreignant la dépendance des composantes du flux de jauge $A_M$ de dix dimensions sur les coordonnées Minkowskiennes et $\psi$, nous retrouvons une action à quatre dimensions semblable à celle de QCD. Entre autres, cette action réduite contient des termes de masse de mésons vectoriels lesquels sont reliés aux composantes du flux de jauge. Nous calculons les valeurs de ces masses et nos prédictions sont comparables aux valeurs expérimentales.

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Souza, Naiara Célida dos Santos de. "A difusão e assimilação de CO2 em folhas C4 (Saccharum spp. e Sorghum bicolor) e suas relações com o nitrogênio foliar e o deficit hídrico." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11144/tde-25042017-173033/.

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O aumento para demanda na produção de alimentos associado a possíveis alterações climáticas globais tem promovido um interesse renovado em pesquisas envolvendo o metabolismo fotossintético. Acredita-se que com o melhoramento fotossintético a produtividade das culturas aumente. Para se alcançar este objetivo, além do uso de práticas biotecnológicas, ainda são necessários estudos abordando as limitações intrisecas do processo fotossintético que possam contribuir com a identificação de alvos para a engenharia genética. Neste contexto, esta tese aborda perguntas especificas sobre a regulação da fotossíntese C4 pela nutrição nitrogenada, o deficit hídrico e a interação destes dois fatores. No primeiro capítulo experimental foi desenvolvido um estudo envolvendo os efeitos da nutrição nitrogenada na difusão interna de CO2. Foi observado que o conteúdo de nitrogênio (N) foliar é determinante para a condutância interna de CO2 (? 18O-gm). Um menor conteúdo de N induz reduções iniciais em ? 18O-gm devido menor atividade das enzimas carboxilativas. Conforme o conteúdo de N reduz em folhas mais velhas alterações na antomia passaram a contribuir com a regulação de ? 18O-gm. No segundo capítulo, foi explorada a variação genotipica de cana-de-açúcar quanto a parâmetros relacionados a fotossíntese e o nitrogênio foliar, envolvendo a eficiência de uso de nitrogênio fotossintética (PNUE) e índices de herdabilidade. A variabilidade dos materiais genéticos foi explicada principalmente pelos parâmetros de trocas gasosas que contribuíram com o agrupamento dos materiais em três grupos. A partir deste agrupamento é possível verificar as diferenças entre os materiais em reposta a nutrição nitrogenada. Além disto, parâmetros de trocas gasosas como a taxa de assimilação de CO2 e condutância estomática junto com PNUE apresentaram altos índices de herdabilidade no sentido restrito. Por fim, o terceiro capítulo investigou a regulação do metabolismo de assimilação de CO2 em resposta ao deficit hídrico em folhas de cana-de-açúcar e como o metabolismo de nitrogênio está envolvido neste processo. Diferentes fatores envolvidos na regulação negativa da fotossíntese foram identicados. Interesantemente, alterações nos componentes nitrogenados só contribuíram com a inibição metabólica na fase de estresse severo. Adicionalmente foi observado que a superação da inibição metabólica durante a reidratação é mais rápida quando a cultivar apresenta decréscimos mais lentos no metabolismo de N no período de seca, associado a menores danos na capacidade fotossintética.
Increased demand for food production and the possibility of global climate change has promoted renewed interest in photosynthesis research. It is expected that with the photosynthetic improving the crop productivity increase. For this, besides of the use of biotechnological practices, further studies are needed about intrinsic limitations of the photosynthetic process that can contribute to the identification of targets for genetic engineering. In this context, this thesis discusses specific questions about photosynthesis regulation C4 by nitrogen nutrition, water deficit and the interaction of these two factors. In the chapter I, it was developed a study of the effects of nitrogen nutrition in the internal diffusion of CO2. It was observed that the leaf nitrogen (N) is essential for the internal CO2 conductance (Δ 18O-gm). A lower leaf N induces initial reductions in Δ18O-gm by lower activity of the carboxylation enzymes. With N leaf reduction in older leaves anatomy changes began to contribute to the regulation of Δ18 O-gm. In the chapter II, the genotypic variation of sugarcane to photosynthetic parameters and leaf nitrogen was explored, involving the photosynthetic nitrogen use efficiency (PNUE) and heritability analysis. The variability of the genetic material is explained mainly by gas exchange parameters that contributed to the grouping of materials into three groups. From this, it is possible examine the differences between the materials in response to nitrogen nutrition. Furthermore, gas exchange parameters such as CO2 assimilation rate and stomatal conductance along with PNUE showed high heritability in the narrow sense. Finally, the chapter III investigated the regulation of CO2 assimilation metabolism in response to water deficit sugarcane leaves and how nitrogen metabolism is involved in this process. Different factors involved in the negative regulation of photosynthesis were identified. Interestingly, changes in nitrogen components only contributed to metabolic inhibition in severe stress. Additionally it noted that overcoming metabolic inhibition during rehydration is faster when the cultivar presents slower decreases in N metabolism during water deficit, associated with less damage to the photosynthetic capacity.

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Oliveira, Leonardo Bernardes Taverny. "Aspectos morfofisiológicos e nutricionais das forrageiras Mombaça e Marandu na Amazônia em sistema silvipastoril." Universidade Federal do Tocantins, 2015. http://hdl.handle.net/11612/175.

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Objetivou com o presente trabalho avaliar a influência de níveis de sombreamento natural sobre as propriedades morfofisiológicas e nutricionais das forrageiras Panicum maximum cv. Mombaça e Urochloa brizantha (syn. Brachiaria) cv. Marandu em sistema silvipastoril. O experimento foi conduzido na Escola de Medicina Veterinária e Zootecnia da Universidade Federal do Tocantins. Foram avaliadas duas espécies forrageiras Panicum maximum cv. Mombaça e Urochloa brizantha cv. Marandu, sob três gradientes de sombreamento (0, 25 e 50%). Na lâmina foliar foi mensurada a espessura dos tecidos parenquimáticos (mesofilo), componentes do feixe vascular (metaxilema e metafloema), bainha do feixe vascular, epidermes abaxial e adaxial, células buliformes, bainha esclerenquimática, calota esclerenquimática, extensão esclerenquimática, comprimento de cloroplastos e espessamento secundário da epiderme; teor de clorofilas a, b, total e carotenóides; concentração de Ca2+, Mg2+, P, K+ e N. Foi utilizado método multivariado de Análise de Componentes Principais para selecionar as variáveis mais responsivas na discriminação de espécies e a ser usada no teste de médias. A forrageiras de melhor resposta ao sombreamento natural foi o capim Mombaça que mostrou habilidade adaptativa traduzida em elementos essenciais a sua sobrevivência e produção, como espessura de mesofilo que foi maior que no Marandu em sombreamento de 25%; a relação clorofila a:b também apresentou resposta análoga, (1,32 e 1,03), com aumento na proporção de clorofila b. A menor sensibilidade do Mombaça ao sombreamento em relação ao Marandu resultou em maior proporção de tecido esclerenquimático que tem baixa degradabilidade ocasionando em menor produção de gases.
The objective of the present work to check the power of adaptation of Panicum maximum cv. Mombasa and Urochloa brizantha (syn. Brachiaria) cv. Marandu in silvopastoral system and the most responsive variables different swings luz.O experiment was conducted at the School of Veterinary Medicine and Animal Science of the Federal University of Tocantins were evaluated two forage species Panicum maximum cv. Mombasa and Brachiaria brizantha cv. Marandu under three shading levels (0, 25 and 50%). In the leaf blade was measured the thickness of the parenchyma tissue (mesophyll), components of the vascular bundle (metaxylem and metafloema), the vascular bundle sheath, abaxial epidermis and adaxial, bulliform cells, sclerenchymatic sheath sclerenchymatic cap, sclerenchymatic extension, length of chloroplasts and secondary thickening of the epidermis; chlorophylls a, b, and total carotenoid; Ca2 +, Mg2 +, P, K + and N was used multivariate method Principal Component Analysis to select the most responsive variables and the discrimination of species to be used in the test medium. The forage better response to natural shading, was Mombasa grass which had its adaptive ability translated into essential to their survival and production, as thick mesophyll which was higher than in Marandu in 25% shading (40 and 27 respectively) ; the chlorophyll a: b also showed similar response, (1.32 and 1.03), an increase in the proportion of chlorophyll b. The lower sensitivity of Mombasa to shading in relation to Marandu resulted in a higher proportion of sclerenchyma that has low degradability resulting in lower production of gas.

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Kotchetkoff-Henriques, Olga. "Composição floristica e estrutura de uma mata mesofila semidecidua na cabeceira do rio da cochoeira, Serra de Itaqueri, Itirapina, SP." [s.n.], 1989. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315807.

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Orientador : Carlos Alfredo Joly
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-07-15T06:10:19Z (GMT). No. of bitstreams: 1 Kotchetkoff-Henriques_Olga_M.pdf: 8271257 bytes, checksum: a228cd23025e5cab94ff36371506fd96 (MD5) Previous issue date: 1989
Resumo: No presente estudo foi feito o censo das espécies arbóreas com diâmetro igual ou superior a 5 cm a 130 cm do solo, em 1284,5 m2 na margem esquerda da cabeceira do Rio da Cachoeira, afluente do Alto Passa-Cinco. O local é um vale profundo, com inclinação média de 45°, e muito sujeito a perturbações como deslizamento de pedras e queda de árvores. Foram calculados os parâmetros fitossociológicos de densidade e dominância, e as espécies ordenadas de acordo com o IVC, índice do valor de cobertura. Os indivíduos foram mapeados e foi analisado a padrão espacial das espécies. Foram encontrados 892 indivíduos arbóreos, distribuídos em 32 famílias e 85 espécies. As espécies mais abundantes são Urera baccifera (14.79 %), Piper amalago (8.63 %), Machaerium stipitatum (4.71%), Eupatorium macrophyllum (4.48 %), Mortas (3.92 %), Bauhinia forficata (3.70 %), Chorisia speciosa (3.36 %) e Carica quercifolia (3.13 %). As famílias com maior n6mero de indivíduos são Leguminosae (15,02 %), Urticaceae (14,79 %), Piperaceae (9,75 %), Meliaceae (7.62 %), e Compositae (4.71 %). As famílias com maior riqueza floristica são Leguminosae, com 18 espécies (20,69 %); Meliaceae, com 7 espécies (8.05 %); Moraceae e Euphorbiaceae, com 6 espécies cada (6,90 %) e Piperaceae, com 5 espécies (5.75 %). As espécies com maior IVC são Urera baccifera (27,27), Chorisia speciosa (13,02), Piper amalago (10,30), Mortas (9,66), Erythrina falcata (9,46), Bauhinia forficata (6,79), Machaerium stipitatum (6,60), Jacaratia spinosa (6,46), Croton floribundus (6,35), Eupatorium macrophyllum (6,29) e Carica quercifolia (5,56). As familias com maior IVC são Leguminosae (37,08), Urticaceae (27,58), Bombacaceae (13,18), Euphorbiaceae (12,18), Meliaceae (12,13), Caricaceae (12,02), Piperaceae (11,64), Moraceae (11,10), e Mortas (9,66). Para as espécies que apresentam os maiores IVCs foi feita a análise do padrão espacial. Todas apresentam padrão espacial agrupado, exceto Chorisia speciosa e Carica quercifolia. A análise do mapa do local estudado mostra a existência de duas áreas com características diferentes. ... Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital
Abstract: On the present study, a census was taken of the tree species with a diameter equal or superior of 5 cm to 130 cm from the ground in 1284,5 m2 from the left banks of the head of the Rio da Cachoeira, an affluent to the Alta Passa Cinco. The place is a deep valley with an average slope of 45°, and it is subjected to natural perturbations like the falling of stones and trees. The phytossociologics parameters of density and dominance had been calculated and the species ordenated in accordance with the IVC, the index of the worth of covering. The specimens had been maped out and the spatial pattern of the species were analyzed. Eight hundred and ninety-two tree specimens were broken into 32 families and 85 species. The speeies with the greatest number of specimens are Urera baccifera (14,79),Piper amalago (8.63 %), Machaerium stipitatum (4.71%), Eupatorium macrophyllum (4.48 %), Mortas (3.92 %), Bauhinia forficata (3.70 %), Chorisia speciosa (3.36 %) and Carica quercifolia (3.13 %). The families with the greatest number of specimens are Leguminosae (15,02 %), Urticaceae (14,79 %), Piperaceae (9,75 %), Meliaceae (7.62 %), and Compositae (4.71 X). The families with the greatest floristic wealth are Leguminosae, with 18 species (20,69 X); Meliaceae, with 7 species (8.05 X); Moraceae and Euphorbiaceae, with 6 species each one (6,90 %, and Piperaceae, with 5 species (5.75 X).The species with the greatest IVC are Urera baccifera (27,27), Chorisia speciosa (13,02), Piper amalago (10,30), Mortas (9,66), Erythrina falcata (9,46), Bauhinia forficata (6,79), Machaerium stipitatum (6,60), Jacaratia spinosa (6,46), Croton floribundus (6,35), Eupatorium macrophyllum (6,29) and Carica quercifolia (5,56). The families with the greatest IVC are Leguminosae (37,08), Urticaceae (27,58)Bombacaceae (13, 18) , Euphorb iaceae (12, 18) , Me 1iaceae (12,13), Caricaceae (12,02), Piperaceae (11,64), Moraceae (11,10), e Mortas (9,66). ... Note: The complete abstract is available with the full electronic digital thesis or dissertations
Mestrado
Ecologia
Mestre em Ciências Biológicas

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Chen, Long. "A ultraviolet complete large N thermal QCD model: renormalization group flow and mesonic spectra." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=119566.

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The large N thermal Quantum Chromodynamics (QCD) that we study here is a generalization of SU(3) QCD with two gauge groups at high energy scales, i.e. in the ultraviolet (UV). Both gauge groups are related to N as SU(N)×SU(kN) with k < 1. In our construction, we have a model that has a complete UV description, as well as a low energy, i.e. infrared (IR), behaviour that mimicks that of QCD. Our model has three regions. The IR region is the well known cascading model with extensions to include favours. The two gauge groups of this theory reduce to a single SU(kN) group which then confines. The UV region uses congurations from type IIB string theory on the conifold to describe the dynamics. The intermediate region smoothly connects the two, i.e. the UV and the IR, so that we have a complete model for all energy scales. All regions are related to the gauge theory by gauge/gravity duality. In particular, we analyze the renormalization group (RG) flow of the gauge coupling in the effective field theory. We see that it asymptotically approaches a constant at high energies and flows toward permanent confinement as energy scale decreases. In the IR, we obtain the mesonic spectrum by compactifying extra dimensions and analyzing the wave functions in Minkowski space-time.
Cette these etudies la limit N -> ∞ de la theorie chromodynamique quantique avec les deux groupes de jauge SU(N)×SU(kN) avec k < 1. Un modele est popose pour donner un description complete a la fois dans le regime ultraviolet(UV) et infrarouge(IR). Le regime IR concorde avec celui d'un modele de cascade, qui reduit de seule groupe de jaude SU(N) puis confine, tandis que le regime UV correspond a la theorie des cordes de type IIB sur conifold. Le regime UV possede alors une dualite de supergravite/jauge s'inscritvant dans la correspondance AdS/CFT. Dans le regime intermediere, notre molele connecte de maniere reguliere entre IR et UV. Le group de renormalization de la theorie effective est ensuite analyse. Nous comparons les resultats experimentaux en spectre du meson de notre modele das le regime IR.

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Danilkin, Igor [Verfasser], Matthias F. M. [Akademischer Betreuer] Lutz, and Achim [Akademischer Betreuer] Schwenk. "Coupled-channel dynamics in mesonic systems / Igor Danilkin. Betreuer: Matthias F. M. Lutz ; Achim Schwenk." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2013. http://d-nb.info/1106454111/34.

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29

Wissel, Sönke. "Mesonic correlation functions from light quarks and their spectral representation in hot quenched lattice QCD." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=982318332.

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30

Werkmeister, Jaime Brooke 1977. "Design and fabrication of the MesoMill : a five-axis milling machine for meso-scaled parts." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/27142.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.
Includes bibliographical references (p. 113-115).
With the increased prevalence of meso-scaled products, new tools are being developed to bridge the gap between fabrication processes tailored for micrometer and millimeter sized features. Compared to its traditional counterpart, a small machine tool designed for meso-scale could potentially have a smaller overall footprint, shorter structural loop and lower cost than a conventional machine; in addition, a small machine presents opportunities for improved machine metrology, and easier environmental control. This paper describes the design of the MesoMill: a test machine designed to evaluate the use of components new to the design of machining centers including wire capstan drives, ball-screw splines, and an air bearing spindle with an integral Z-axis.
by Jaime Brooke Werkmeister.
S.M.

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Danilkin, Igor Verfasser], Matthias F. M. [Akademischer Betreuer] [Lutz, and Achim [Akademischer Betreuer] Schwenk. "Coupled-channel dynamics in mesonic systems / Igor Danilkin. Betreuer: Matthias F. M. Lutz ; Achim Schwenk." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2013. http://d-nb.info/1106454111/34.

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32

Silva, Dalva Maria da. "Estrutura de tamanho e padrão espacial de uma população de Esterpe edulis Mart. (Arecaceae) em mata mesofila semidecidua no municipio de Campinas." [s.n.], 1991. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314981.

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Orientador: Fernando Roberto Martins
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Com o objetivo de obter dados sobre a estrutura de tamanho e o padrão espacial da população de Euterpe edulis Mart. (Arecaceae) presente na área brejosa de uma mata mesófila semidecidua no município de Campinas, SP, uma área de 1,0 ha foi delimitada por 2 eixos de 100m. Foram sorteados 100 pares aleatórios de pontos, cada par correspondendo a uma parcela de 5 x 5m e dentro de cada parcela de 25m2 uma área de 1 x 1m foi sistematicamente marcada. Nas parcelas de 1m2 foram marcados todos os indivíduos com até 3 folhas, considerados plântulas. Nas parcelas de 25m2 foram marcados todos os indivíduos em estádio de desenvolvimento superior ao de plântula. Foram anotados dados sobre a altura, diâmetro, número de folhas e presença de flores e frutos de cada planta. Os indivíduos foram classificados em mais 3 estádios de tamanho: jovem, imaturo e adulto. A população apresentou uma distribuição de tamanho (altura e diâmetro) na forma de J reverso. A distribuição de folhas foi a menos assimétrica. As distribuições de tamanhos para jovens apresentaram maior assimetria. A desigualdade de tamanhos diminuiu com o aumento do tamanho das plantas. A população como um todo apresentou um padrão aleatório, mas a tendência à agregação aumentou com o aumento do tamanho das plantas. Não houve correlação entre a densidade e o tamanho médio dos indivíduos. O número médio de indivíduos, em qualquer estádio, foi maior em parcelas alagadas
Abstract: This study investigates the size structure and the spatial pattern of a population of Euterpe edulis Mart. (Arecaceae) in a mesophyll semidecidous forest, of São Paulo State, SP Brazil. An are a of 1,0 ha was choosen and delimited by 2 orthogonaJ axes of 100m. A hundred random pairs of points were taken. Each pair corresponded to a 5 x 5m plot. lnside each 25m2 plot, an area of 1 x was demarcated. Every plant until 3 leafs were tagget inside the 1m2 plots, these plants were considered seedlings. lnside 25m2 plot ali the plants bigger than seedling were tagget. Their height, girth, number of leaves and presence or absence of infrutescence and inflorescence were recorded. The individuaIs were classified in 4 size states: seedling, young, imature and adulto The size structure analisys indicated that the size (height and girth) distributions had a reverse J shape and were more assimetrical for young than for other states. The leaves distribution was less assimetrical than the others. The size inequality reduced with the increase of the plant size. The population as a whole presented a randorn spatial pattern. The tendency towards aggregation increased with the increase of the plant Size. No correlation was found between the mean size of plants and plant density. The mean number of plants, in any state was bigger in swampy plots
Mestrado
Mestre em Biologia Vegetal

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33

Ricciardulli, Vittorio. "Analisi dello spettro di massa invariante j/psi pi+ pi- in collisioni p-p a sqrt(s) = 8 tev con il rivelatore cms." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/6617/.

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In questo lavoro di tesi è stato studiato lo spettro di massa invariante del sistema J/psi pi+ pi-, m(J/psi pi+ pi-), in collisioni protone-protone a LHC, con energia nel centro di massa sqrt(s)) pari a 8 TeV, alla ricerca di nuovi stati adronici. Lo studio è stato effettuato su un campione di dati raccolti da CMS in tutto il 2012, corrispondente ad una luminosità integrata di 18.6 fb-1. Lo spettro di massa invariante m(J/psi pi+ pi-), è stato ricostruito selezionando gli eventi J/psi->mu+ mu- associati a due tracce cariche di segno opposto, assunte essere pioni, provenienti da uno stesso vertice di interazione. Nonostante l'alta statistica a disposizione e l'ampia regione di massa invariante tra 3.6 e 6.0 GeV/c^2 osservata, sono state individuate solo risonanze già note: la risonanza psi(2S) del charmonio, lo stato X(3872) ed una struttura più complessa nella regione attorno a 5 GeV/c^2, che è caratteristica della massa dei mesoni contenenti il quark beauty (mesoni B). Al fine di identificare la natura di tale struttura, è stato necessario ottenere un campione di eventi arricchito in adroni B. È stata effettuata una selezione basata sull'elevata lunghezza di decadimento, che riflette la caratteristica degli adroni B di avere una vita media relativamente lunga (ordine dei picosecondi) rispetto ad altri adroni. Dal campione così ripulito, è stato possibile distinguere tre sottostrutture nello spettro di massa invariante in esame: una a 5.36 GeV/c^2, identificata come i decadimenti B^0_s-> J/psi pi+ pi-, un'altra a 5.28 GeV/c^2 come i candidati B^0-> J/psi pi+ pi- e un'ultima allargata tra 5.1 e 5.2 GeV/c^2 data da effetti di riflessione degli scambi tra pioni e kaoni. Quest'ultima struttura è stata identificata come totalmente costituita di una combinazione di eventi B^0-> J/psi K+ pi- e B^0_s-> J/psi K+ K-.

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Tsang, Yik Chong. "The effect of aberrations and light scatter on visual performance at photopic and mesopic light levels." Thesis, City University London, 2013. http://openaccess.city.ac.uk/2476/.

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The Contrast Acuity Assessment (CAA) test was developed to assess the minimum spatial vision requirements for commercial pilots. The goal of the CAA test was for it to be sensitive to retinal image degradation in subjects who had undergone excimer laser refractive surgery. Increased aberrations and scattered light or abnormal processing of visual information in the retina and/or the visual pathway are the main causes of retinal image degradation. The purpose of this study was to further investigate the effect of aberrations, scatter and other parameters on the CAA test under photopic and mesopic conditions. This could help to provide explanations for previous CAA test results. The effect of contrast, stimulus onset time, pupil size and crowding on the CAA test was examined. This was in order to try to provide explanations for the decline in Landolt ring gap acuity over the central 5 degrees, as observed in previous CAA test results, which had shown a foveal dip to occur under photopic and mesopic conditions. Contrast Sensitivity was measured on eight subjects using 6 and 3 mm artificial pupils using the City University Contrast Sensitivity Test. A significant trend of decreasing contrast sensitivity with increased pupil size occurred for the middle and lower spatial frequencies (1.2 and 6.1 cpd), but not for the highest 19.1 cpd spatial frequency. The effects of using high contrast (125%) rather than low contrast (24%) CAA test targets were investigated, in combination with the use of artificial pupils of 6 mm and 3 mm. We concluded that low contrast could play a role in producing a foveal dip under photopic and mesopic conditions. The effect of crowding and stimulus onset time on the CAA Test was examined on 3 subjects, by reducing the contrast of the fixation guides under mesopic and photopic conditions and increasing stimulus onset time. This gave inconclusive results. No significant conclusions were drawn concerning the effect of crowding or stimulus onset time on the CAA foveal dip. The effect of aberrations on normal subjects on the photopic and mesopic CAA test was examined, to determine whether they may have influenced the foveal dip. 14 subjects were tested with natural pupils, under photopic conditions and 10 subjects, were tested under mesopic conditions. A Shack Hartmann aberrometer was used to take wavefront aberration measurements. No significant regressions were found between aberrations and foveal dip. We concluded that aberrations were probably not the cause of the foveal dip. Q value lenses consisting of Q = -2, Q = -1, Q = 0, Q = +1 and Q = +1.5 contact lenses were tested on subjects with natural pupils, to determine whether the CAA test could pick up larger non-physiological changes in aberrations. Large changes in visual performance were observed. Z (4,0) spherical aberration versus central CAA gap acuity was found to produce a significant quadratic regression under mesopic conditions. Seidel coma and Seidel astigmatism were also found to produce significant linear regressions. under photopic conditions. Scatter was measured in 4 subjects, using 6 mm and 3 mm artificial pupils, to determine whether scatter would increase with the larger pupil size. Linear regressions of scatter k’ versus foveal dip gave results which were not statistically significant. Scatter was measured for 3 subjects using the 5 different Q value contact lenses, to see if the Q values affected the scatter. The results were not statistically significant. The differences in scatter produced were found to be far less than the increase of scatter found in two subjects with pathological conditions. We concluded that scatter played an insignificant role in producing the foveal dip or changing visual performance with the use of Q value contact lenses. The project produced a systematic investigation of the parameters affecting the CAA test. A statistically significant association, described by a quadratic regression curve, exists between CAA mesopic gap acuity and Z (4,0) spherical aberration.

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Carvalho, Lucila Maria Lopes de. "Sucessão e ecologia de populações de insetos associados a decomposição de carcaças de suinos expostas em ambiente natural de mata mesofila semidecidua, Campinas-SP." [s.n.], 1996. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314226.

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Orientador: Aricio Xavier Linhares
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-07-21T03:55:00Z (GMT). No. of bitstreams: 1 Carvalho_LucilaMariaLopesde_M.pdf: 4838401 bytes, checksum: 1703f9307377ca9eae245f3b7d52c48d (MD5) Previous issue date: 1996
Resumo: A existência dos insetos sarcosaprófagos, principalmente das famílias Calliphoridae e Sarcophagidae, é conhecida há tempos, porém, o padrão sucessional destes em carcaça, só recentemente tem sido estudado nos trópicos. O presente trabalho foi desenvolvido na Reserva Mata de Santa Genebra, Estado de São Paulo, e aspectos da sucessão, diversidade, abundância relativa de adultos e imaturos, dos estágios de decomposição, sazonalidade e espécies indicadoras forenses foram abordados. Foram utilizados dois porcos domésticos por cada estação do ano, expostos à condições de sol e sombra. A sucessão não foi muito marcante, apesar da diversidade ter sido alta para ambas famílias. Os califorídeos predomínaram sobre os sarcofagídeos tanto nos adultos coletados como nos adultos criados. O local da sombra teve maior número de indivíduos coletados e o sol, maior número de indivíduos que criaram-se na carcaça. Chrysomya albiceps (Calliphoridae) foi a espécie mais abundante em todos os experimentos, mostrando ser a principal espécie que explora o recurso. Fêmeas de Cochliomyia maceUaria, C. albiceps, Chrysomya putoria e Phaenicia eximia utilizaram a carcaça como recurso proteíco e Bemilucilia segmentaria, para a oviposição. O estágio de decomposição de putrefação escura e fermentação foram os mais representativos quanto à frequência dos dípteros, sendo influenciados pela temperatura e precipitação. O estudo demonstrou serem esses dípteros os principais agentes que atuam na decomposição da carcaça, sendo assim, importantes para a Entomologia Forense. As espécies que se destacaram como indicadoras forenses para a região natural de mata, foram B. segmentaria (Calliphoridae) e Pattonella intermutans (Sarcophagidae)
Abstract: The existence of sarcosaprophagous insects specialIy Calliphoridae and Sarcophagidae families, is known a long time ago, however, the successional pattern of them in carcass only has been studied recently in tropics. The present study was done at "Reserva Mata de Santa Genebra", Southeastern Brazil, and some aspects of succession, diversity, relative abundance of larvae and adult, stages of decomposition, seasonality and species as forensic indicators were taken. Two domestic pigs were used for each season and exposed to sun and shade. The diversity was high in both families, but the entomological sucession wasn't clearly determinated. The calliphorid had predominated than sarcophagid in number of adults colIected and reared on carcass. The sun had colIected more insects and the shade had reared a great number of individuaIs. The abundance ofChrysomya albiceps (Calliphoridae) was higher in alI experiments and this specie was the better explorer of source. The carcass was a protein source to Cochlyomyia macellaria, C. albiceps, C. putoria and Phaenicia eximia, despite Hemilucilia segmentaria had used a carcass to oviposit. The stages of decomposition of carcass were influenced by temperature and precipitation and the putrefation and fermentation were more representatives than others. This work showed that these flies were the principal agents that do the decomposition of carcass, therefore are important to Forensic Entomology. Only two species could be used as forensic indicators in this natural area : H. segmentaria (Calliphoridae) and Pattonella intermutans (Sarcophagidae )
Mestrado
Parasitologia
Mestre em Ciências Biológicas

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36

Khan, Naseemuddin [Verfasser], and Jan M. [Akademischer Betreuer] Pawlowski. "Interplay of Mesonic and Baryonic Degrees of Freedom in Quark Matter / Naseemuddin Khan ; Betreuer: Jan M. Pawlowski." Heidelberg : Universitätsbibliothek Heidelberg, 2015. http://d-nb.info/1180608348/34.

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ROJAS, PUEBLA ITZEL 655802, and PUEBLA ITZEL ROJAS. "Calidad microbiologica en tres hortalizas producidas en el Estado de México." Tesis de maestría, Universidad Autónoma del Estado de México, 2017. http://hdl.handle.net/20.500.11799/65583.

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La creciente preocupación de los consumidores por mantener una dieta sana y equilibrada, ha hecho que el consumo de hortalizas frescas aumente. Al mismo tiempo han incrementado los problemas de salud de los consumidores debido a la contaminación de alimentos por bacterias enteropatógenas, siendo las hortalizas, para consumo en fresco, las que presentan mayores posibilidades de convertirse en vehículos de microorganismos patógenos. Debido a la importancia de las hortalizas como fuente de Enfermedades Transmitidas por Alimentos (ETA). La presente investigación tuvo como objetivo determinar la calidad de origen microbiológico de plantas de lechuga (Lactuca sativa L), cilantro (Coriandrum sativum L) y espinaca (Spinacia oleracea L), producidos en Calimaya, Toluca y Tenango del Valle, Estado de México. Los estudios se realizaron durante el proceso de cosecha del ciclo de cultivo 2015, se determinó la cantidad de Mesófilos Aerobios (MA), Coliformes Totales (CT) y Coliformes Fecales (CF) presentes en 180 muestras de hortalizas, seis muestras de agua de riego y seis de suelo de cultivo. Se utilizaron las metodologías establecidas en las Normas Oficiales Mexicanas: y la Normatividad de la Organización Nacional Francesa para la Estandarización (AFNOR) NF V08-60. Se utilizó un diseño experimental completamente al azar y un análisis de varianza para localidades y una prueba de Tukey (p≤0,05). Los resultados obtenidos arrojan que, para las muestras de hortalizas, el nivel de microorganismos MA, CT y CF, se encontraron dentro de los límites máximos permisibles por las NOM. Se comprobó la presencia de bacterias CF en las hortalizas, por lo que se realizó un análisis confirmativo mediante una resiembra en medios selectivos, una comprobación bioquímica y serológica, confirmando la presencia de bacterias del género Escherichia coli del Serotipo O105 ab flagelar. Los análisis de agua de riego de la lechuga cultivada en el municipio de Calimaya sobrepasaron los límites de CF 12 UFC/mL.
Universidad Autónoma del Estado de México, Facultad de Ciencias Agrícolas. Proyecto: Calidad microbiologica de tres hortalizas producidas en el Estado de México. clave: 3791/2014/CID

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Cardoso, Angela Libia de Melo Pereira. "Ocorrencia, multiplicação e produção de toxina diarreica por cepas mesofilas e psicotroficas de Bacillus cereus, em leite pasteurizado." [s.n.], 2000. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255116.

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Orientador: Mauro Faber de Freitas Leitão
Tese (doutorado) - Universidade Estadual de Campinas. Faculdade de Engenharia de Alimentos
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Resumo: Nesta pesquisa foi avaliada a ocorrência de Bacillus cereus em amostras de leite comercial pasteurizado, bem como seu potencial de deterioração em função da temperatura de incubação e a capacidade de produção de enterotoxina diarréica nesse substrato. Numa etapa inicial foram analisadas 240 unidades de amostras de leite comercial pasteurizado dos tipos A, B e C, estudando-se a presença e os níveis de contaminação por células vegetativas e esporos de B. cereus mesófilo e psicrotrófico. Os resultados revelaram a presença da bactéria em 116 (48,3%) das unidades de amostra analisadas, com maiores incidências nos leites tipo C comparativamente ao B e A (67,5 50 e 27,5 % de positividade nos tipos C, B e A respectivamente). Predominaram níveis baixos de contaminação, na faixa de 102UFC/rnL,com maiores contagens nas amostras de leite tipo C, comparativamente aos outros tipos. Em nenhuma das amostras analisadas constatou-se a presença de cepas psicrótroficas de B. cereus. Nos ensaios envolvendo a inoculação experimental de amostras de leite seguido de incubação às temperaturas de 5°, 10°, 15° 20° e 30°C, verificou-se a ausência de alterações nas temperaturas mais baixas (5° e 10°C)e o rápido crescimento e deterioração nas amostras mantidas acima de 15°C.As alterações mais pronunciadas foram evidenciadas pela coagulação do leite, nítida separação de fases com reduzidas modificações nos valores de pH e acidez titulável. Comprovou-se a possibilidade seleção de gradativa de cepas capazes de crescimento em temperatura de refrigeração (7°C), partindo-se de cepas originalmente mesófilas; no entanto, o processo de seleção foi lento, sendo que somente após 21 dias de incubação as culturas apresentaram multiplicação mais rápida, com tempo de geração (G) mínimo de 2,17 dias. Quanto à capacidade de produção de enterotoxina por teste imunoenzimático, na maioria das cepas isoladas e testadas foram observados resultados positivos, tanto em meios de cultura como utilizando o leite como substrato. No entanto, nas amostras de leite inoculadas experimentalmente, a produção de enterotoxina somente foi constatada em temperaturas acima de 15°C, não sendo observada nas amostras mantidas sob refiigeração (7° e 5°C), mesmo após 12 dias de incubação.
Abstract: The incidence of Bacillus cereus, its spoilage potential in relation to the incubation temperature and the capacity of diarrheic enteroxin prodution were evaluated in commercial pasteurized milk samples. A total of 240 samples of pasteurized milk types A, B and C were analysed for the incidence and counts of mesophilic and psycrotrophic B. cereus. The results showed the occurrence of B. cereus in the 116 (48.3%) of the examined samples with higher incidence in type C when compared to the types B and A (67,5, 50.0 and 27,5% of positive samples for types C, B and respectively). In most ofthe samples prevaled counts around '10 POT.2' CFU/mL,with higher values in type C milk when compared to types B and A. No sychrotrophic strains were isolated in the examined samples. In the experiments envolving inoculation of B. Bereus in mi1k samples followed by incubation at different temperatures it was noticed that B.cereus was not able to grow at refrigeration temperatures (5° and 10°C) but with fast growth and spoilage activity at higher temperatures (15°, 20° e 30°). The main evidences of spoilage were characterized by coagulation and clear separation of phases but without remarkable changes in pH and total acidity values. In an other experiment it was shown the possibility of gradual selection of psycrotrophic B. cereus strains originating from originally mesophilic cultures. However this selection was gradual and only afier an incubation period of 21 days the selected strains showed multiplication with a minimum "G" value of 2.17 days. Most of the tested strains originaly isolated from commercial milk samples showed capacity of diarrheic enterotoxin production both in culture media and milk samples. However in the inoculated milk samples the enterotoxin prodution was observed only in incubation temperatures above 15°C, without production at 7°C and 5°C even after 12 days of incubation.
Doutorado
Doutor em Tecnologia de Alimentos

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Espino, Stuard Lucero Regina. "Recuento de bacterias aerobias mesofilas totales en canales bovinas mediante el método de hisopado en un camal de Lima Metropolitana." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2006. https://hdl.handle.net/20.500.12672/758.

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La finalidad de los exámenes microbiológicos en el camal es evaluar el grado de higiene de los procesos de faena, ya que los principales agentes infecciosos e intoxicaciones alimentarias llegan a la carne durante estos procesos, el presente estudio se desarrolló en un camal de Lima metropolitana, entre los meses de octubre y noviembre del 2004, se muestrearon 30 canales bovinas al azar, un día por semana, en días alternos durante 4 semanas. el objetivo fue determinar la contaminación microbiológica de las canales mediante el Recuento de Bacterias Aerobias Mesofilas Totales antes de la conservación en frío, se utilizó el método de muestreo no destructivo del hisopado y un medio de cultivo rápido, Petrifilm, se hisopó falda, pecho, cuello y cadera; (100 cm2 por área) según lo establece la legislación vigente, los datos fueron expresados en Logaritmos de unidades formadoras de colonias ufc/cm2; encontrando los siguientes valores: 2.69, 2.75, 3.19, 2.23, 2.49, 2.84, 2.42, 3.18, 2.72, 2.44, 2.70, 3.27, 2.92, 2.9, 2.52, 3.08, 2.79, 2.01, 3.10, 4.11, 3.99, 4.39, 1.95, 3.08, 2.97, 3.27, 3.39, 2.59, 3.51, 3.45; siendo contrastados con limites microbiológicos diseñados en el presente correspondiendo a un nivel de 43.33 % de aceptabilidad, la 53.3 % al área dudosa y 3.3 % de inaceptabilidad, siendo el promedio de estos 3.04 Log ufc/cm2, los resultados muestran una S: 0.568 y un C.V: 18.58 %. Palabras Clave: Canales, faena, bacterias, aerobias, camal.
--- The finality from the exams microbiogical in the slaughterhouses, is gauge the gradation the hygiene from process the slaughtered meat, the principals agents infecctions e intoxication alimentary to arrive a the meat during this process, the present study to develop in an slaughterhouses of Lima metropolitan, betwixt the months of October and November of 2004, to sampling 30 slaughtered meat cattles the hazard, an day for week, in days alternates during 4 weeks, the objetive was to determine the contamination microbiogical of the slaughtered means of the Recount of aerobic bacterias mesophilic Totals before of the conservation in cold, to utilized the method of sampling not destructive from swabs and an medium of culture rapid the Petrifilm, to swabs the successive areas: rump, flank, brisket, neck; 100 cm2 for area, on the establish the legislation actual, the datas the expressing in terms of logaritmos of colonys formings units per cm2 (ufc/cm2), was: 2.69, 2.75, 3.19, 2.23, 2.49, 2.84, 2.42, 3.18, 2.72, 2.44, 2.70, 3.27, 2.92, 2.9, 2.52, 3.08, 2.79, 2.01, 3.10, 4.11, 3.99, 4.39, 1.95, 3.08, 2.97, 3.27, 3.39, 2.59, 3.51, 3.45; middle the this 3.04 Log ufc/cm2 , this results indication a S: 0.568 y un C.V: 18.58 %, correspond an level of 43.3% of acceptability, 53.3% in the area of doubt, and 3.3 % of unacceptable. Key Words: carcass, cattles, contamination, microbiogical, swabs.
Tesis

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Benfenati, Francesco. "Modello statico a quark degli adroni leggeri." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/16789/.

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Lo scopo di questa tesi è quello di trattare il Modello Statico a Quark, o Modello a Quark Costituenti (CQM), in riferimento alla composizione degli adroni leggeri. Questo modello fu proposto indipendentemente da Gell-Mann e Zweig nel 1964 per tentare di spiegare le proprietà che si osservavano degli adroni, ed è oggi il modello maggiormente utilizzato fra quelli efficaci. Come per tutti i risultati della Fisica delle Particelle, anche questo si inserisce in quel contesto di continuo confronto fra Fisica Teorica e Sperimentale che ha contraddistinto in particolare modo questa branca della Fisica. Ci limiteremo a discutere il modello originario, quello del 1964, ovvero quello che comprende solamente i tre quark più leggeri up, down e strange, gli unici noti all’epoca. Per farlo partiremo nel primo capitolo da un’introduzione generale del Modello Standard e delle caratteristiche che riguardano maggiormente il modello di Gell-Mann e Zweig, seguendo talora un approccio che ricalca la storia scientifica, ovvero prendendo le mosse dalle osservazioni sperimentali, da cui sono seguite poi le deduzioni. Nel secondo capitolo affronteremo da un punto di vista più tecnico, ma non cadendo nell’eccessivo formalismo matematico, le basi della Teoria dei Gruppi, una teoria che trova molteplici applicazioni nel Modello Standard e da cui esso non può prescindere. In particolare ci limiteremo ai soli aspetti utili ai fini della formulazione del CQM. La trattazione è, dunque, anche un esempio concreto di applicazione alla Fisica della Teoria dei Gruppi. Nel terzo ed ultimo capitolo, infine, vedremo come il Modello Statico a Quark descrive e classifica gli stati adronici leggeri e le loro proprietà osservate in natura.

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Cordisco, Lisa <1979&gt. "Adattamento e acclimatazione a diverse temperature di lieviti psicrofili obbligati e facoltativi e di lieviti mesofili. Studio della produzione di acidi grassi polinsaturi omega-3 e omega-6 per via fermentativa." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1530/.

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Adaptation and acclimation to different temperatures of obligate psychrophilic, facultative psychrophilic and mesophilic yeasts. Production of ω-3 and ω-6 polyunsaturated fatty acids by fermentative way. Obligate psychrophilic, facultative psychrophilic and mesophilic yeasts were cultured in a carbon rich medium at different temperatures to investigate if growth parameters, lipid accumulation and fatty acid composition were adaptive and/or acclimatory responses. Acclimation of facultative psychrophiles and mesophiles to lower temperature negatively affected their specific growth rate. Obligate psychrophiles exhibited the highest biomass yield (YX/S), followed by facultative psychrophiles, then by mesophiles. The growth temperature did not influence the YX/S of facultative psychrophiles and mesophiles. Acclimation to lower temperature caused the increase in lipid yield (YL/X) in mesophilic yeasts, but did not affect YL/X in facultative psychrophiles. Similar YL/X were found in both facultative and obligated psychrophiles, suggesting that lipid accumulation is not a distinctive character of adaptation to permanently cold environments. The extent of unsaturation of fatty acids was one major adaptive feature of the yeasts which colonize permanently cold ecosystems. Remarkable amounts of α-linolenic acid were found in obligate psychrophiles at the expenses of linoleic acid, whereas it was generally scarce or absent in all the others strains. Increased unsaturation of fatty acids was also an acclimatory response of mesophiles and facultative psychrophiles to lower temperature. It’s well known that omega-3 polyunsaturated fatty acids (PUFAs) display a variety of beneficial effects on various organ systems and diseases, therefore a process for the microbial production of omega-3 PUFAs would be of great interest. This work sought also to investigate if one of the better psychrophilic yeast, Rhodotorula glacialis DBVPG 4785, stimulated by acclamatory responses, produced omega-3 PUFAs. In fact, the adaptation of psychrophilic yeasts to cold niches is related to the production of higher amounts of lipids and to increased unsaturation degree of fatty acids, presumably to maintain membrane fluidity and functionality at low temperatures. Bioreactor fermentations of Rhodotorula glacialis DBVPG 4785 were carried out at 25, 20, 15, 10, 5, 0, and -3°C in a complex medium with high C:N ratio for 15 days. High biomass production was attained at all the temperatures with a similar biomass/glucose yield (YXS), between 0.40 and 0.45, but the specific growth rate of the strain decreased as the temperature diminished. The coefficients YL/X have been measured between a minimum of 0.50 to a maximum of 0.67, but it was not possible to show a clear effect of temperature. Similarly, the coefficient YL/S ranges from a minimum of 0.22 to a maximum of 0.28: again, it does not appear to be any significant changes due to temperature. Among omega-3 PUFAs, only α-linolenic acid (ALA, 18:3n-3) was found at temperatures below to 0°C, while, it’s remarkable, that the worthy arachidonic acid (C20:4,n-6), stearidonic acid (C20:4,n-3) C22:0 and docosahexaenoic acid (C22:6n-3) were produced only at the late exponential phase and the stationary phase of batch fermentations at 0 and -3°C. The docosahexaenoic acid (DHA) is a beneficial omega-3 PUFA that is usually found in fatty fish and fish oils. The results herein reported improve the knowledge about the responses which enable psychrophilic yeasts to cope with cold and may support exploitation of these strains as a new resource for biotechnological applications.

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Rosales, Angeles Fabiana. "Digesti��n anaerobia mesof��lica de residuos de frutas y verduras al 6% de s��lidos totales." Thesis, Universidad de las Am��ricas Puebla, 2012. http://catarina.udlap.mx/u_dl_a/tales/documentos/lqi/rosales_a_f/.

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Cunha, Jardel Dantas da. "Avalia??o de heterociclo do tipo mesoi?nico solubilizado em sistema microemulsionado para aplica??o em dutos." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12674.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
The efficiency of inhibition to corrosion of steel AISI 1018 of surfactant coconut oil saponified (SCO) and heterocyclic type mesoionics (1,3,4-triaz?lio-2-tiolato) in systems microemulsionados (SCO-ME and SCO-ME-MI) Of type O/A (rich in water emulsion) region with the work of Winsor IV. The systems microemulsionados (SCO-ME and SCO-ME-MI) were evaluated with a corrosion inhibitor for use in saline 10,000 ppm of chloride enriched with carbon dioxide (CO2). The assessment of corrosion inhibitors were evaluated by the techniques of linear polarization resistance (LPR) and loss of weight (MW) in a cell instrumented given the gravity and electrochemical devices. The systems were shooting speed of less than 60 minutes and efficiency of inhibition [SCO-ME (91.25%) and SCO-ME-MI (98.54%)]
As efici?ncias de inibi??o ? corros?o em a?o AISI 1018 do tensoativo ?leo de coco saponificado microemulsionado (OCS-ME) e do composto heterociclo do tipo mesoionico (MI) solubilizado neste sistema OCS-ME, foram avaliadas pelas t?cnicas de resist?ncia a polariza??o linear (LPR) e perda de massa (PM) em uma c?lula instrumentada dotada destes dispositivos. O sistema microemulsionado OCS-ME ? do tipo O/A (emuls?o rica em ?gua) apresentando regi?o de trabalho em winsor IV. Os sistemas microemulsionados OCS-ME e OCS-ME-MI foram avaliados como inibidores de corros?o para aplica??o em solu??o salina 10.000 ppm de cloreto, enriquecidos com di?xido de carbono (CO2). Estes sistemas apresentam velocidades de filmagem inferiores a 60 minutos e efici?ncias de inibi??o a corros?o significativas [OCS-ME (91,25 %) e OCS-ME-MI (98,54 %)]

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Araujo, Glein Monteiro de. "Comparação da estrutura e do teor de nutrientes nos solos e nas folhas de especies arboreas de duas matas mesofilas semideciduas no triangulo mineiro." [s.n.], 1992. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316155.

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Orientador : Mundayatan Haridasan
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Compararam-se os teores de nutrientes nos solos e nas folhas de espécies arbóreas de duas matas mesófilas semidecíduas, no Município de Uberlândia, MG, a fim de determinar a influência da fertilidade do solo sobre a nutrição mineral dessas comunidades. Foi realizado um levantamento fitossociológico de espécies arbóreas (circunferência a altura do peito igualou maior do que 10 cm) , em 50 parcelas de 10 m x 10 m, em cada mata. Uma na Estação Ecológica do Panga e outra na Fazenda Experimental do Glória, ambas pertencendo à Universidade Federal de Uberlândia. Foram analisadas amostras de solo dos horizontes A~ e As, de cada parcela, quanto à textura, ao teor de matéria orgânica, ao pH e às disponibilidades de nutrientes. Foram analisadas amostras de folhas de todas as espécies arbóreas encontradas nas duas áreas para determinar as concentrações de N, P, K, Ca, Mg, Fe, Mn, Zn, Cu e Al. Solos e folhas foram coletados simultaneamente no final da estação chuvosa. Foram encontradas 151 espécies, 104 gêneros e 53 famílias nas duas matas. Na mata do Panga, foram encontradas 93 espécies, 73 gêneros e 42 famílias, com uma densidade de 2202 árvores ha-~ e área basal de 23,8 m2 ha-1. Na mata do Glória, levantaram-se 96 espécies, 78 gêneros e 44 famílias, com 1632 árvores e área basal de 28 m2 ha-1. Foram comuns às duas matas 38 espécies, 47 gêneros e 36 famílias. o índice de diversidade de Shannon para espécies foi de 3,7 na mata do Panga e 4,1, na do Glória. As cinco espécies mais importantes na mata do Panga foram: Lithraea molleoides, Chrysophyllum marginatum, Campomanesia velutina, Alibertia sessilis e Terminalia brasiliensis, representando 30% do total do índice de valor de importância (IVI). Ocotea corymbosa, Cryptocarya moscat, Machaerium villosum, Copaifera langsdorfii e Casearia grandiflora, as cinco espécies mais importantes da mata do Glória representaram apenas 20% do total de IVI. o solo sob a mata do Panga apresentou textura franco arenosa, enquanto o do Glória, argilosa. o pH do solo, a disponibilidade de Ca e de Mn , e a saturação de bases no horizonte AJ. foram maiores na mata do Panga do que na do Glória. o teor de matéria orgânica, a saturação de AI e a disponibilidadede Fe, Mn, Zn, Cu e AI foram maiores no solo do Glória. Os solos das duas áreas não apresentaram diferenças significativas nos teores de K e Mg, no horizonte AJ.. O único nutriente em que ocorreu uma inversão nas disponibilidades entre os horizontes AJ. e As, nos solos das duas matas, foi o Mn. O solo do Glória apresentou maiores teores de Mn no horizonte As do que o solo do Panga. As espécies exclusivas e de maior IVI do Panga tiveram maiores teores de Ca e de K, e menores de Mg do que as do Glória. Foram encontrados teores foliares de 15,7 a 59,5 mg/g de Ca em 42 espécies do Panga, enquanto a maioria das espécies da mata do Glória teve menos de 10,8 mg/g. As espécies comuns às duas matas mantiveram um melhor equilíbrio nas concentrações foliares de macronutrientes catiônicos. K. Ca e Mg, do que as espécies exclusivas e de maior IV!. Não foram observadas diferenças significativas entre as duas comunidades nas concentrações foliares de N e P. A relação P/N foi muito baixa na maioria das espécies nas duas matas, parecendo indicar que o P é, talvez, o macronutriente mais limitante nos solos dessas duas fitocenoses. Situadas em solo com pH mais elevado, as espécies exclusivas e de maior IVI do Panga, apresentaram menores teores de Mn do que as espécies da mata do Glória. Em comparação com outras fitocenoses de cerrado e cerradões brasileiros, encontrou-se um número maior de acumuladoras de Mn com concentrações foliares maiores que 300 mg/kg nas duas matas estudadas: 31 espécies no Glória e 11 no Panga. Ao contrário, encontrou-se um número menor de espécies acumuladoras de AI nas duas matas: 5 espécies no Panga e 7 no Glória
Abstract: The soil availability and foliar concentrations of nutrients in the tree species of two mesophytic semideciduous forests in Triângulo Mineiro, Minas Gerais, were compared to determine the influence of soil fertility on the mineral nutrition of these two communities. Phytosociological surveys of tree especies (circunference at breast height greater than or egual to 10 cm) were carried out in fifty 10 m x 10 m plots in each forest, one at Estação Ecológica do Panga and the other at Fazenda Experimental do Glória, both properties belonging to the Universidade Federal de Uberlândia. Soil samples from the A1 and A3 horizons from each plot were analyzed to determine soil texture, pH, organic matter content and the availability of plant nutrients. Leaf samples from alI tree species in the two areas were analyzed to determine their concentrations of N, P, K, Ca, Mg, Fe, Mn, Zn, Cu and AI. The soil and leaf samples were collected at the end of the rainy season. A total of 151 species belonging to 104 genera and 53 families were present in the two forests. Ninety-three species belonging to 73 genera and 42 families, with a tree density of 2202 individual ha-1 and a basal area of 23.8 m2 h-1, were encountered in the forest community at Panga and ninety-six species belonging to 78 genera and 44 families, with a tree density of 1632 individuaIs ha-1 and a basal area of 28 m2 ha-1 , in the forest community at Glória. Thirty-eight species belonging to 47 genera and 36 familias were common to both communities. The Shannon diversity index for species was 3.7 at Panga and 4.1 at Glória. The five most important species at Panga were Lithraea molleoides, Chrysophyllum marginatum, Campomanesia velutina, Alibertia sessilis and Terminalia brasiliensis, accounting for 30% of the total of the importance value index. Ocotea corymboBa, Cryptocarya moschata ta, Machaerium villosum, Copaifera langsdorfii and Casearia grandiflora, the five most important species at Glória accounted for only 20% of the total of the importance value index. The soil at Panga was sandy loam and the soil at Glória was clayey. Soil pH, available Ca and Mn, and base saturation were higher in the A~ horizon at Panga than at Glória. Organic matter content, saturation of AI and availabiity of Fe, Zn, Cu and AI were higher at Glória. There was no significant difference between the two soils in the availability of K and Mg in the A1 horizon. The only inversion in these differences at lower depths occurred in Mn availability. The soil at Glória showed significantly higher concentrations of Mn in the As horizon than the soil at Panga. Species with the highest importance values at Panga and those exclusive to Panga had higher foliar concentrations of Ca and K and lower concentrations of Mg than those at Glória. The Ca concentrations in the 42 tree species at Panga varied from 15.7 to 59.5 mg/g while most of the species at Glória had concentrations lower than 10.8 mg/g. Species common to both areas showed a better equilibrium among the foliar concentrations of the major nutrient cations K, Ca and Mg, than the exclusive ones and those with the highest importance values. There were no significant differences between the two communities in the foliar concentrations of N and P. The P/N ratio was very low in most of the species in both areas, which indicates that P was probably the most limiting major nutrient in these two ecosystems. The species exclusive to Panga and those with highest importance values showed lower Mn concentrations than those at Glória, as would be expected from the higher pH of the soil at the former site. As compared to cerrado sensu stricto and cerradão commun ities of central Brazil, a larger number of manganese-accumulating species with foliar concentrations above 300 mg!kg (31 at Glória and 11 at Panga) was detected in the two areas. On the contrary, ony a few Al-accumulating species (five at Panga e 7 at Glória) were present in the two communities
Doutorado
Ecologia
Doutor em Ciências

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45

Drca, Milan. "Seuchenhygienisch-mikrobiologische Untersuchungen an einer mesophil betriebenen Biogasanlage zur Verwertung von Speiseresten in Verbindung mit methodischen Untersuchungen zum Nachweis von Salmonellen und Escherichia coli aus biologischem Material." Doctoral thesis, Universitätsbibliothek Leipzig, 2007. http://nbn-resolving.de/urn:nbn:de:bsz:15-20071108-144306-2.

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ZUSAMMENFASSUNG Milan Drča Seuchenhygienisch-mikrobiologische Untersuchungen an einer mesophil betriebenen Biogasanlage zur Verwertung von Speiseresten in Verbindung mit methodischen Untersuchungen zum Nachweis von Salmonellen und Escherichia coli aus biologischem Material Institut für Tierhygiene und Öffentliches Veterinärwesen der Veterinärmedizinischen Fakultät der Universität Leipzig und Institut für Umwelt- und Tierhygiene sowie Tiermedizin mit Tierklinik der Universität Hohenheim 156 Seiten, 17 Tabellen, 35 Abbildungen, 307 Literaturstellen, 1 Anhang Seuchenhygienisch-mikrobiologische Untersuchungen Es wurden folgende Versuchsvarianten an der Biogasanlage berücksichtigt: Keimträgerversuche während der Hygienisierung, Keimträgerversuche im mesophilen Reaktor und hygienisch-bakteriologische Untersuchungen des Substrates vor und nach der anaeroben Vergärung. Das Ziel der Tenazitätsversuche mit den Keimträgern Typ 1 und Typ 2 während der Pasteurisierung und im mesophilen Reaktor lag darin, nachzuweisen, ob eine sichere Inaktivierung seuchenhygienisch relevanter Bakterien und Viren zu erreichen ist. Es wurden folgende Bakterien und Viren verwendet: Listeria monocytogenes, Yersinia enterocolitica, Salmonella Senftenberg W775 H2S negativ, Escherichia coli, Campylobacter jejuni, Enterococcus faecalis, Felines Calicivirus, ECBO-Virus und Bovines Parvovirus. Zusätzlich zu den Keimträgerversuchen wurde das Substrat vor und nach der anaeroben Behandlung („Input- und Outputkontrolle“) auf seinen Gehalt an Salmonellen, Enterokokken und Gesamtcoliforme sowie Fäkalcoliforme untersucht. Das Ziel der durchgeführten Untersuchungen lag darin, die Effektivität der in der Biogasanlage ablaufenden Prozesse zu überprüfen. Die Ergebnisse der Versuche zur Tenazität der eingebrachten Bakterien während der Hygienisierung zeigten bei allen untersuchten Bakterien eine Inaktivierung bzw. Keimzahlreduktion um mehr als sieben Zehnerpotenzen. Die Ergebnisse der Versuche zur Tenazität der eingebrachten Viren während der Hygienisierung zeigten eine vollständige Inaktivierung von ECBO- und Felinen Caliciviren. Dagegen konnte das Bovine Parvovirus während des gesamten Hygienisierungsprozesses nicht inaktiviert werden. Am Ende der Hygienisierung betrug die Konzentration noch 102,0 (KID50/ml) bei einem Ausgangstiter von 104,50 (KID50/ml). Im mesophilen Reaktor wurden die ermittelten Konzentrationen von Salmonella Senftenberg W775 H2S negativ und Escherichia coli in einer Zeitspanne von 7 d um mehr als acht Zehnerpotenzen reduziert. Enterococcus faecalis erwies sich als wesentlich thermostabileres Testbakterium. Nach 14 d Aufenthaltszeit wurde die ermittelte Ausgangskonzentration von 108 KBE/ml um sechs Zehnerpotenzen reduziert. Die Ergebnisse der hygienisch-bakteriologischen Untersuchungen der Substrate nach der Hygienisierung bzw. die ermittelten Konzentrationen von Gesamtcoliforme, Fäkalcoliforme und Enterokokken zeigten eine Inaktivierung von 5 log 10. In keiner der untersuchten Input- und Outputproben konnten Salmonellen nachgewiesen werden. Untersuchungen zum Nachweis von Salmonellen aus biologischem Material Ziel der vorliegenden Untersuchungen war es, die entsprechenden vier CEN-Nachweismethoden für Salmonellen mit den Substraten Klärschlamm-, Gülle und Erde zu erproben, um deren Eignung für die Praxis beurteilen zu können. Es wurden artifiziell kontaminierte Proben untersucht. Als Testbakterien diente Salmonella Senftenberg. Alle drei verwendeten Salmonella-Konzentrationen (101, 102 und 103 KBE/ml) konnten durch die Methode 2 (MPN-Verfahren) und Methode 3 (Filtrationsmethode) bei allen drei beimpften Substraten wiedergewonnen werden. Der qualitative Nachweis von Salmonella Senftenberg (Methode 4) konnte ebenfalls bei allen untersuchten Proben erbracht werden. Ein Vergleich der beiden Methoden 1 und 2, die jeweils der Ermittlung der wahrscheinlichsten Keimzahl dienen, zeigte die Ungenauigkeit der Methode 1. Das angewandte MPN-Verfahren der Methode 1 lieferte bei allen untersuchten Substraten, die mit einer Konzentration von 102 und 103 KBE/ml beimpft waren, einen ungenauen Wert von >2,4 x 102 KBE/ml. Aufgrund der angewandten Nachweisverfahren sowie der gewonnenen Ergebnisse (mit Ausnahme der Methode 1) konnte festgestellt werden, dass die vorgeschlagenen Entwürfe zum Nachweis von Salmonellen für alle drei untersuchten Substrate geeignet sind. Untersuchungen zum Nachweis von Escherichia coli aus biologischem Material 120 natürlich kontaminierte Gülle-, Klärschlamm-, Speiserest- und Bioabfallproben wurden mittels zweier quantitativen MPN- Nachweismethoden (Makro- und Mikromethode) untersucht. Die gewonnenen Maximal- und Medianwerte der Makromethode lagen bei allen untersuchten Substraten durchschnittlich zwischen einer halben und einer Zehnerpotenz höher als bei der Mikromethode. Eine Ausnahme stellten allerdings die Medianwerte der untersuchten Gülleproben und die Maximalwerte der untersuchten Speiseabfallproben dar. Hierbei zeigten die beiden Methoden vergleichbare Werte. Aufgrund der Ergebnisse und der Tatsache, dass die Makromethode drei biochemische Eigenschaften von Escherichia coli umfasst, und damit eine sicherere Identifizierung von Escherichia coli gewährleistet, empfiehlt sich daher, bei Untersuchungen von biologischem Material die Makromethode anzuwenden.

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Quintero, Jesús M. "Assessment of color quality and energy effciency : new insights for modern lighting. Part I : color quality in general lighting applications. Part II : mesopic photometry and street lighting." Doctoral thesis, Universitat Politècnica de Catalunya, 2015. http://hdl.handle.net/10803/286285.

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This dissertation is divided in two parts: The first one deal with two main characteristics of the light sources for general lighting: Color quality and luminous efficacy. The second one deals with technical aspects of the mesopic photometry applied in street lighting. The first part begins by proposing a method to generate a new color rendering index, consisting of a three-dimensional visual index, which was named 3D-CRM. In order to illustrate the use of this method and index, three examples of lighting application were performed: Artwork, meat and fruit. The results show the goodness of the visual index 3D-CRM, that is also accompanied by a numeric index that indicates how the light source tested fits with the gamut of colors required by the specific lighting application. Complementing the preceding proposal, a statistical analysis was performed in order to define the parameters that make up the color quality of light sources. This statistical study was based on a collection of more than 100 real and ideal spectra of light sources. As a result, it was found that there is another variable that can complement the CRI index to indicate the color quality. This is the proposed index Oc (Optimal Color), which is based on the calculation of volumes generated with the spectrum of test source and several ideal spectra of reflectance to get optimal colors (high saturated colors) at different luminance levels. This fisrt part of the dissertation ends by proposing an index to generate a classification of light sources according to the requirements of the lighting application and the parameters such as correlated color temperature (CCT), luminous efficacy of radiation (LER) and color quality (CQ). It was demonstrated that the new proposed index called ECQ (Efficacy and Color Quality), is able to generate a useful ranking when assessing a collection of spectra, by giving a desired CCT and the weight that efficacy and color quality have in the lighting application studied. By using some examples of different lighting applications (i.e. different weights for color quality and efficacy) it was demonstrated how versatile and useful the ECQ index is. In the second part of this dissertation, a comparison of laboratory measurements between two different types of goniophotometers is made. The first one is a standard and photometer-based one, which uses the far-field for measurement. The second one has a more recent technology, uses a CCD camera and photometer as sensors, as well as the near field for measurement. This comparison exercise validates the measurements from the near-field goniophotometer, since up to moment, for this type of measurement and type of sensor (CCD camera), there are no laboratories with international traceability that can verify or calibrate this measurement system. The comparison exercise shows that there is a very good fit between both measures performed to standard light bulbs; therefore results of the near-field goniophotometer are validated. In recent measures performed at the Light and lighting laboratory of K.U. Leuven in Ghent, it was found that near field goniophotometer has a reduced luminous intensity dynamic range, for this reason exists an error measuring low luminous intensities in a luminarie with a sharp LID such as PAR30 Spot light bulb. After that, some aspects of the Recommended System for Mesopic Photometry Based on Visual Performance, CIE191:2010 are analysed. Finally it is presented a proposal of a new metrics called Energy Consumption Index (Qsa) intended to assessing possible energy savings on street lighting systems. In this chapter, by using the Energy Consumption Index an evaluation of three different hypothetical scenarios for a typical city is performed to demonstrate how flexible and intuitive this index is. These scenarios assess different characteristics of the light system such as light sources types, dimming systems and also the use of photopic and mesopic photometry.
Esta tesis se divide en dos partes: La primera trata con dos características principales de las fuentes de luz para la iluminación general: la calidad del color y de eficacia luminosa. El segundo se ocupa de los aspectos técnicos de la fotometría mesópica aplicada en el alumbrado público. La primera parte comienza proponiendo un procedimiento para generar un nuevo índice de rendimiento de color, que consiste en un índice visual tridimensional, llamado 3D-CRM. Con el fin de ilustrar el uso de este índice, se realizaron tres ejemplos de aplicación de iluminación: Arte, carnes y frutas. Los resultados muestran la bondad del índice visual 3D-CRM, que también se acompaña de un índice numérico que indica que tan bien una fuente de luz bajo prueba repolores la gama de colores para una aplicación de iluminación específica. Como complemento de la propuesta anterior, se realizó un análisis estadístico con el fin de definir los parámetros que componen la calidad de color de fuentes de luz. Este estudio estadístico se basa en una colección de más de 100 espectros reales e ideales de fuentes de luz. Como resultado, se encontró que hay otra variable que puede complementar el índice CRI para indicar la calidad del color. Este es el índice propuesto Oc (óptima del color), que se basa en el cálculo de los volúmenes generados con el espectro de la fuente de prueba y varios espectros ideal de reflectancia para obtener colores óptimos (colores de alta saturación) a diferentes niveles de luminancia. Esta primera parte termina proponiendo un índice para generar una clasificación de las fuentes de luz de acuerdo con los requisitos de la aplicación de iluminación y los parámetros tales como la temperatura de color correlacionada (CCT), la eficacia lumínica de radiación (LER) y la calidad de color (CQ ). Se demostró que el nuevo índice propuesto llamada ECQ (eficacia y calidad del color), es capaz de generar una clasificación útil en la evaluación de una colección de espectros, dando un CCT deseado y el peso que la eficacia y la calidad del color tienen en la aplicación de iluminación estudiado . Mediante el uso de algunos ejemplos de diferentes aplicaciones de iluminación (es decir, diferentes pesos para la calidad del color y la eficacia lumínica) se demostró la versatilidad y utilidad de este indicador. En la segunda parte de esta tesis, se hace una comparación de mediciones de laboratorio entre dos tipos diferentes de Goniofotómetros. El primero es uno estándar basada en el fotómetro, que utiliza el campo lejano para la medición. El segundo tiene una tecnología más reciente, utiliza una cámara CCD y fotómetro como sensores, así como el campo cercano para la medición. Este ejercicio de comparación valida las mediciones de la goniofotómetro de campo cercano, ya que hasta el momento, para este tipo de medición y el tipo de sensor (cámara CCD), no hay laboratorios con trazabilidad internacional que puede verificar o calibrar este sistema de medición. El ejercicio de comparación muestra que hay un muy buen ajuste entre las dos medidas realizadas a las bombillas estándar; Por lo tanto, los resultados del Goniofotómetro de campo cercano se validan. En recientes medidas realizadas en el laboratorio de luz e iluminación de K.U. Lovaina en Gante, se encontró que Goniofotómetro de campo cercano tiene un rango dinámico limitado para medición de intensidad luminosa, por esta razón existe un error de medición de bajas intensidades luminosas en una luminaria con una distribución aguda como por ejemplo un proyector de luz. Posteriormente se analizan, algunos aspectos del sistema recomendado para fotometría mesópica basado en el rendimiento visual, CIE191: 2010. Por último se presenta una propuesta de una nueva métrica llamada Índice de Consumo de Energía (Qsa) destinado a evaluar los posibles ahorros de energía en los sistemas de alumbrado público

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Reis, Camilla Moretto dos. "S?ntese e avalia??o da atividade biol?gica de tiossemicarbazidas, tiossemicarbazonas e cloridratos mesoi?nicos da classe 1,3,4- tiadiaz?lio-2-aminida." Universidade Federal Rural do Rio de Janeiro, 2012. https://tede.ufrrj.br/jspui/handle/jspui/1584.

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq
Nowadays the demand for cleaner and more efficient synthetic processes have been deemed very important, especially due to environmental aspects. Thus, this thesis describes the synthesis of a series of 20 tiossemicarbazidas, nine class of N4-substituted obtained from the reaction of isothiocyanates with different hydrazine hydrate and eleven Class of N1,N4-disubstituted obtained from the reaction of isothiocyanates with different phenyl hydrazine. We used the traditional method by stirring at room temperature, the microwave irradiation and solid-solid maceration for preparing such compounds, the latter methodology to that presented the best performances for the compounds synthesized in only two minutes of reaction. The antioxidant activity of tiossemicarbazidas was evaluated experimentally by the method of DPPH, indicating significant activity for most of the derivatives tested. The tiossemicarbazidas N4-substituted synthetic precursors were derived from the class of 36 thiosemicarbazones, which have also been obtained by three different methodologies from the reaction of different aromatic aldehydes with tiossemicarbazidas N4-substituted. The methodology used by traditional reflux, the microwave irradiation in the presence of organic solvent and microwave irradiation in the absence of solvent, the latter method was allowed to obtain products with better results with only 3 minutes of reaction. All 36 of thiosemicarbazones derivatives were tested against the fungi Candida albicans and Aspergillus parasiticus, with moderate activity for some of the derivatives tested. The tiossemicarbazidas N1,N4-disubstituted are synthetic precursors of the 1,3,4-thiadiazolium-2-aminide hydrochlorides mesoionic class. Eleven mesoionic derivatives were obtained by microwave irradiation, from tiossemicarbazidas N1,N4-disubstituted with different aromatic aldehydes. We also evaluated the cytotoxic activities from some of the synthesized mesoionic lines K562 human leukemia and Jurkat, as well as in the line of Daudi lymphoma, obtaining satisfactory and very promising results for some of the compounds tested. Furthermore, the compounds mesoionic were tested for in vivo activity against L. amazonensis and L. infantum and also opposite the trypanothione reductase enzyme L. amazonensis, L. infantum, L. braziliensis and T. cruzi showing significant activity indicating the potential use of these compounds as anti-parasitic agents
Nos dias atuais as demandas por processos sint?ticos mais limpos e eficientes t?m sido consideradas muito relevantes, devido especialmente aos aspectos ambientais. Assim, este trabalho de tese relata a s?ntese de uma s?rie de 20 tiossemicarbazidas, sendo nove da classe das N4-substitu?das, obtidas a partir da rea??o de diferentes isotiocianatos com hidrazina hidrato e onze da classe das N1,N4-dissubstitu?das obtidas a partir da rea??o de diferentes isotiocianatos com fenil hidrazina. Utilizou-se a metodologia tradicional por agita??o a temperatura ambiente, a irradia??o de micro-ondas e a macera??o s?lido-s?lido para a prepara??o desses compostos, sendo esta ?ltima metodologia a que apresentou os melhores rendimentos para os compostos sintetizados em apenas 2 minutos de rea??o. A atividade antioxidante das tiossemicarbazidas foi avaliada experimentalmente pelo m?todo do DPPH, indicando atividade significativa para a maioria dos derivados testados. As tiossemicarbazidas N4-substitu?das foram os precursores sint?ticos de 36 derivados da classe das tiossemicarbazonas, que tamb?m foram obtidas por tr?s metodologias diferentes a partir da rea??o de diferentes alde?dos arom?ticos com as tiossemicarbazidas N4-substitu?das. Utilizou-se a metodologia tradicional por refluxo, a irradia??o de micro-ondas na presen?a de solvente org?nico e a irradia??o de micro-ondas na aus?ncia de solvente, esta ?ltima metodologia foi a que permitiu a obten??o dos produtos com melhores rendimentos em apenas 3 minutos de rea??o. Todos os 36 derivados das tiossemicarbazonas foram testados frente aos fungos Aspergillus parasiticus e Candida albicans, apresentando moderada atividade para alguns dos derivados ensaiados. As tiossemicarbazidas N1,N4-dissubstitu?das foram os precursores sint?ticos dos cloridratos mesoi?nicos da classe 1,3,4-tiadiaz?lio-2-aminida. Onze derivados mesoi?nicos foram obtidos via irradia??o de micro-ondas, a partir das tiossemicarbazidas N1,N4-dissubstitu?das com diferentes alde?dos arom?ticos. Foram avaliadas, tamb?m, as atividades citot?xicas de alguns dos mesoi?nicos sintetizados nas linhagens leuc?micas humanas K562 e Jurkat, assim como na linhagem de linfoma Daudi, obtendo-se resultados bastante promissores e satisfat?rios para alguns dos compostos ensaiados. Al?m disso, os compostos mesoi?nicos foram ensaiados quanto ? atividade in vivo frente a L. amazonensis e L. infantum e tamb?m frente ? enzima tripanotiona redutase de L. amazonensis, L. infantum, L. braziliensis e T. cruzi mostrando atividade significativa indicando a potencial utiliza??o desses compostos como agentes anti-parasit?rios.

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Carvalho, Fabiana. "A nuvem mesônica, a estranheza e o charme nos hádrons." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-26022014-092505/.

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O objetivo deste trabalho é aplicar o modelo de nuvem mesônica (MCM) aos processos envolvendo colisões hadrônicas e/ ou nucleares. Nós utilizamos o modelo para calcular a distribuição não-singleto de partons no mar dos nucleons, incluindo as contribuições do octeto e decupleto. Demos atenção especial para a diferença entre quarks estranhos e não estranhos do mar, tentando identificar possíveis fontes de quebra de simetria de sabor SU(3). Apresentamos uma análise em termos do parâmetro K e encontramos que a ocorrência da quebra de assimetria de sabor no mar dos nucleons pode ser explicada quantitativamente pela nuvem de mésons. Nós também efetuamos o mesmo tipo de análise para o bárion + e encontramos resultados semelhantes. Com base na idéia de compreender os fenômenos não perturbativos que geram diferentes tipos de assimetria, utilizamos o MCM para estudar a diferença entre a produção de mésons charmosos (D) \"leading\" e \"non-leading\" como função de Xp observadas em colisões 1-A e - A. Um fato interessante dos dados da WA89 e da SELEX é que eles sugerem, apesar das grandes barras de erro e da pouca estatística, que a assimetria decresce em Xp muito grande. Com o modelo de nuvem mesônica nós podemos reproduzir estes dados e observar uma possível queda na assimetria. Tendo em vista os bons resultados do modelo na descrição de processos não perturbativos em colisões à altas energias, realizamos um estudo sobre o fator de forma eletromagnético do píon, baseado na decomposição do píon em estados de nuvem. Comparando nossos resultados com os dados experimentais divulgados pela F Collaboration do Jefferson Laboratory, podemos concluir que a composição dos estados de nuvem do píon não é o efeito dominante na descrição do seu fator de forma eletromagnético, e consequentemente, na sua estrutura interna.
The purpose of this work is to apply the meson cloud model (MCM) in processes involving either hadronic or nuclear collisions. We have calculated the non-singlet parton distribution in the nucleon sea, including the octet and decuplet contributions. We gave special attention to the difference between strange and non-strange sea quarks, trying to identify possible SU(3) flavor symmetry breaking sources. We present an analysis in terms of K parameter and we find that the flavor symmetry breaking in the nucleon sea can be explained quantitatively by the meson cloud. We have also performed the same analysis for the + baryon and we found similar results. We used the MCM to study the difference between \"leading\" and \"non-leading\" charmed mesons (D) observed in -A and -A collisions. An interesting feature in SELEX and WA89 data is that they suggest, in spite of the large error bars and poor statistics, that the asymmetry decreases at large F With the meson cloud model we can reproduce these data and observe this trend in the asymmetry. Motivated by the good results in describing non-perturbative processes in high energy collisions, we have done a study of the pion electromagnetic form factor, based on a pion decomposition in cloud states. Comparing our results with the experimental data reported by Jefferson Lab. F Collaboration, we can conclude that the meson cloud of the pion is not the dominant effect to describe its electromagnetic form factor, and hence, its internal structure.

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49

Pranchai, Aor. "Spatial patterns and processes in a regenerating mangrove forest." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-171569.

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The global effort to rehabilitate and restore destroyed mangrove forests is unable to keep up with the high mangrove deforestation rates which exceed the average pace of global deforestation by three to five times. Our knowledge of the underlying processes of mangrove forest regeneration is too limited in order to find suitable techniques for the restoration of degraded mangrove areas. The general objective of my dissertation was to improve mangrove restoration by understanding regeneration processes and local plant-plant interaction in a regenerating Avicennia germinans forest. The study was conducted in a high-shore mangrove forest area on the Ajuruteua peninsula, State of Para, Northern Brazil. The dwarf forest consisting of shrub-like trees is recovering from a stand-replacing event caused by a road construction in 1974 which interrupted the tidal inundation of the study area. Consequently, infrequent inundation and high porewater salinity limit tree growth and canopy closure. All trees and seedlings were stem-mapped in six 20 m x 20 m plots which were located along a tree density gradient. Moreover, height, crown extent, basal stem diameter of trees were measured. The area of herbaceous ground vegetation and wood debris were mapped as well. The mapped spatial distribution of trees, seedlings and covariates was studied using point pattern analysis and point process models, such as Gibbs and Thomas point process, in order to infer underlying ecological processes, such as seed dispersal, seedling establishment, tree recruitment and tree interaction. In the first study (chapter 2), I analyzed the influence of abiotic and biotic factors on the seedling establishment and tree recruitment of A. germinans during the recolonization of severely degraded mangrove sites using point process modeling. Most seedlings established adjacent to adult trees especially under their crown cover. Moreover, seedling density was higher within patches of the herbaceous salt-marsh plants Blutaparon portulacoides and Sesuvium portulacastrum than in uncovered areas. The higher density of recruited A. germinans trees in herb patches indicated that ground vegetation did not negatively influence tree development of A. germinans. In addition, tree recruitment occurred in clusters. Coarse wood debris had no apparent effect on either life stage. These results confirm that salt-marsh vegetation acts as the starting point for mangrove recolonization and indicate that the positive interaction among trees accelerates forest regeneration. In the second study (chapter 3), I analyzed how intraspecific interaction among A. germinans trees determines their growth and size under harsh environmental conditions. Interaction among a higher number of neighboring trees was positively related to the development of a focal tree. However, tree height, internode length and basal stem diameter were only positively associated in low-density forest stands (1.2 trees m-2) and not in forest stands of higher tree density (2.7 trees m-2). These results indicated a shift from facilitation, i.e. a positive effect of tree interaction, towards a balance between facilitation and competition. In the third study (chapter 4), I used point process modeling and the individual-based model mesoFON to disentangle the impact of regeneration and interaction processes on the spatial distribution of seedlings and trees. In this infrequently inundated area, propagules of A. germinans are only dispersed at a maximum distance of 3 m from their parent tree. Furthermore, there is no evidence that the following seedling establishment is influenced by trees. I was able to differentiate positive and negative tree interactions simulated by the mangrove model mesoFON regardless of dispersal processes based on static tree size information using the mark-correlation function. The results of this dissertation suggest that mangrove forest regeneration in degraded areas is a result of facilitative and not competitive interactions among mangrove trees, seedling and herbaceous vegetation. This has important implications for the restoration of degraded mangrove forest. Degraded mangrove areas are usually restored by planting a high number of evenly spaced seedlings. However, high costs constrain this approach to small areas. Assisting natural regeneration could be a less costly alternative. Herbaceous vegetation plays a crucial role in forest recolonization by entrapping propagules and possibly ameliorating harsh environmental conditions. So far only competition among mangrove trees has been considered during restoration. However, facilitative tree interactions could be utilized by planting seedling clusters in order to assist natural regeneration instead of planting seedlings evenly-spaced over large areas. This dissertation also showed that point pattern analysis and point process modeling can enable forest ecologists to describe the spatial distribution of trees as well as to infer underlying ecological processes.

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Rodrigues, Cláudio Roberto Barbosa Simões. "Contribuições ao uso de diodos emissores de luz em iluminação pública." Universidade Federal de Juiz de Fora, 2012. https://repositorio.ufjf.br/jspui/handle/ufjf/1695.

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No intuito de aportar contribuições ao uso de diodos emissores de luz (ou LEDs, do inglês Light Emmiting Diodes) em sistemas de iluminação pública, cobrindo lacunas existentes no cenário nacional, este trabalho traz uma ampla análise sobre este tema. São apresentados conceitos básicos da fotometria clássica e um estudo sobre adaptações da fotometria para baixos níveis de luminância, que é a condição observada nas vias públicas durante o período noturno. Propõe-se a utilização de métricas escotópicas em sistemas de iluminação pública, uma vez que estas melhor representam a real sensação visual (se comparadas às métricas clássicas – fotópicas) nas condições de iluminamento típicas observadas nestes sistemas. Aspectos gerais da iluminação pública e um histórico da evolução do sistema nacional são brevemente apresentados bem como uma discussão sobre a situação atual deste sistema e das tecnologias utilizadas. O trabalho traz também um estudo sobre características ópticas, elétricas e mecânicas dos LEDs e uma análise dos diferentes tipos de LEDs brancos mais utilizados (HB – High Brightness – e HP – High Power – LEDs). Algumas normas e recomendações aplicáveis à utilização de LEDs em iluminação pública são analisadas e discutidas, com o intuito de se investigar lacunas ainda não cobertas pela normatização existente. Análises de resultados de ensaios de laboratório e de campo, inéditos no país, realizados com alguns modelos de luminárias LED para iluminação pública disponíveis no mercado, são também apresentadas. Um estudo sobre acionamento de LEDs é realizado, abordando técnicas de equalização de corrente entre arranjos série de LEDs associados em paralelo e diferentes tipos de circuitos de acionamento para LEDs. São propostas, analisadas e implementadas uma estrutura inédita de baixo custo para a equalização de corrente e um circuito para o acionamento de LEDs baseado na integração de dois conversores cc cc não isolados. A topologia de dois estágios proposta é composta por um conversor boost no primeiro estágio, utilizado para a correção do fator de potência e por um conversor buck no segundo estágio, utilizado para o controle da corrente nos LEDs. Por fim, o acompanhamento da implantação e do desempenho, ao longo de dez meses, do projeto piloto de iluminação pública empregando LEDs instalado no anel viário da Faculdade de Engenharia da UFJF é apresentado.
In order to present contributions to the use of light emitting diodes (LEDs) in public lighting systems, covering gaps on the national scenario, this work encompasses abroad analysis related to this issue. Basic concepts of classical photometry are presented and so a study of photometry’s adaptations for low luminance levels. It is proposed the use of scotopic metrics for street lighting systems, since they can better represent the actual visual sensation (when compared to the classical one – photopic metrics) on its typical nighty conditions. General aspects of street lighting and the history of the national’s public lighting system are briefly presented as well as a discussion about the current situation of the Brazilian system and technologies adopted. The work also brings a study of mechanical, electrical and optical characteristics of LEDs and an analysis of the two different types of commonly used white LEDs (HB – High Brightness – and HP – High Power - LEDs). Some standards and recommendations related to the use of LEDs in street lighting are analyzed and criticized, with the aim of show some gaps not yet covered by the existent standards. An unprecedented analysis regarding laboratory and field test benchmarking, taken for some luminaires available in commerce, is also presented. A study of LED driving is presented, covering equalization techniques for parallel LEDs strings and different types of LED driving circuits. It was proposed, analyzed and implemented a novel and low cost structure for current equalization and an LED driver, based on the integration of two non-isolated dc dc converters. This proposed two stages topology is composed by a boost converter, on the first stage, employed to the power factor correction and a buck converter, on the second stage, to control the LED’s current. Finally, the process of monitoring the installation and the performance, during ten months, of the LEDs public lighting pilot project, on the roadway belt of Engineering Faculty of UFJF is presented.

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