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Moura, CÃcero Pessoa de. "Estudo de remoÃÃo do benzeno, tolueno, p-xileno e o-xileno dissolvidos em Ãgua por adsorÃÃo em organosÃlica periÃdica mesoporoso (PMO)." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8871.
Повний текст джерелаАнотація:
Este estudo avalia a organosÃlica com mesoporos periÃdicos (PMO), sintetizada pela co-condensaÃÃo de 1,4-bis(trietoxisilil)benzeno (BTEB) e feniltrietoxisilano (FTE), em fraÃÃes molares variÃveis, sob condiÃÃes Ãcidas, usando o copolÃmero tribloco PlurÃnic P123 como agente direcionante na presenÃa de sal inorgÃnico (KCl), na adsorÃÃo de compostos aromÃticos presentes em soluÃÃo aquosa sintÃtica.
A composiÃÃo molar das sÃnteses seguiu a equaÃÃo de sÃntese xFTE:1,00-xBTEB:0,03P123:7,66KCl:1,28HCl:425,35H2O, onde x variou de 0,0, 0,2 e 0,4., designando os sÃlidos obtidos como PMO1,0; PMO0,8; e PMO0,6, cujos Ãndices indicam a fraÃÃo do BTEB na composiÃÃo da mistura reacional.
Estruturalmente, observou-se que a incorporaÃÃo do FTE ao processo gera PMOs com estabilidade tÃrmica reduzida, com menores valores de Ãrea superficial e de volumes de poros alÃm de menor carÃter hidrofÃlico. As medidas de difraÃÃo de raios X a baixo Ãngulo, a microscopia eletrÃnica de transmissÃo e a isoterma de adsorÃÃo e dessorÃÃo de nitrogÃnio revelaram que os produtos estÃo hexagonalmente ordenado, possuem poros cilÃndricos e de dimensÃes meso/macro complementares.
Os testes para remoÃÃo dos compostos aromÃticos dissolvidos em Ãgua, o PMO1,0 e PMO0,6 exibiram eficientes capacidades de adsorÃÃo para benzeno, tolueno, p-xileno e o-xileno (BTXs). Nos ensaios de adsorÃÃo com PMO0,6, em batelada, as capacidades de remoÃÃo do benzeno (0,84 mg.g-1), tolueno (0,93 mg.g-1), p-xileno (1,00 mg.g-1) e o-xileno (0,86 mg.g-1) foram menores que as obtidas nos testes de adsorÃÃo em coluna: benzeno (1,15 mg.g-1), tolueno (1,26 mg.g-1), p-xileno (1,25 mg.g-1) e o-xileno (1,15 mg.g-1). O mecanismo cinÃtico de adsorÃÃo Ã, prioritariamente identificado como de pseud-segunda ordem e as isotermas podem ser representadas pelos modelos de Redlich-Peterson e Temkin.This study evaluates the Periodic Mesopores Organosilicas (PMO) synthesized by co-condensation of 1,4-bis(trietoxysilil)benzene (BTEB) and feniltrietoxysilane (FTE) in different mole fractions, under acidic conditions using triblock copolymer Pluronic P123 as template and in the presence of inorganic salt (KCl), to adsorption of aromatic compounds in aqueous synthetic solution. The molar composition of the synthesis followed the synthesis equation: xFTE :29,58-xBTEB: 1.0 P123: 226.75 KCl: 38HCl: 12583H2O, where x ranged from 0 to 11.83, as designating the solids obtained as PMO1,0; PMO0,8; and PMO0,6, whose index indicates the fraction of BTEB in the composition of the mixture. Structurally, it was observed that incorporation of FTE to process generates PMOs with reduced thermal stability, with lower values of surface area and pore volume and lower hydrophilic character. The measures for small angle of X-ray diffraction, the transmission microscopy and the isotherm of nitrogen adsorption and desorption showed that the products are hexagonally ordered cylindrical pores and has dimensions of meso/macro complementary. The tests for removal of aromatic compounds dissolved in water, the PMO1,0 and PMO0,6 exhibited efficient adsorption capacity of benzene, toluene, p-xylene and o-Xylene (BTXs). In the adsorption experiments with PMO0,6, in batch study, the capacity of removing benzene (0,84 mg.g-1), toluene (0,93 mg.g-1), p-xilene (1,00 mg.g-1) e o-xilene (0,86 mg.g-1) were lower than those obtained in the tests adsorption column: benzene (1,15 mg.g-1), toluene (1,26 mg.g-1), p-xilene (1,25 mg.g-1) e o-xilene (1,15 mg.g-1). The kinetic mechanism of adsorption is primarily identified as pseud-second order and the isotherms can be represented by Redlich-Peterson and Temkin models.
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King, Myron Decker. "An efficient sequential BTRS implementation." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/46603.
Повний текст джерелаАнотація:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2009.Includes bibliographical references (leaves 73-74).
This thesis describes the implementation of BTRS, a language based on guarded atomic actions (GAA). The input language to the compiler which forms the basis of this work is a hierarchical tree of modules containing state, interface methods, and rules which fire atomically to cause state transitions. Since a schedule need not be specified, the program description is inherently nondeterministic, though the BTRS language does allow the programmer to remove nondeterminism by specifying varying degrees of scheduling constraints. The compiler outputs a (sequential) single-threaded C implementation of the input description, choosing a static schedule which adheres to the input constraints. The resulting work is intended to be used as the starting point for research into efficient software synthesis from guarded atomic actions, and ultimately a hardware inspired programming methodology for writing parallel software. This compiler is currently being used to generate software for a heterogeneous system in which the software and hardware components are both specified in BTRS.
by Myron Decker King.
S.M.
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Fjordestam, Patrik, and Sebastian Hansen. "Control and monitoring of a BTES-system." Thesis, Högskolan i Halmstad, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-30207.
Повний текст джерелаАнотація:
During the summer excess energy is produced from solar heaters, this is not taken care of, and usually goes to waste. The base of the project is built on that you should take the excess energy during the warmest months of the summer and save the energy in boreholes in the ground, then during the colder months the energy can be used. The purpose of the project was to build a prototype for the control and monitoring of a system. With this project we want to present a solution to a prototype which can be used as a development platform for the client. Communication between the actuators, sensors and the controller is made via a CAN-bus. The temperature sensors uses a One-wire buss and its values are stored and can be shown on a website. The results show that the monitoring and control functions works. Theoretically, the prototype is designed to be expanded to a real application.Under sommaren produceras överbliven energi från solvärmare, denna tas inte omhand utan går oftast till spillo. Projektets grund bygger på att ta den överblivna energin under de varmaste månaderna på sommaren och spara undan energin i borrhål i marken, för att sedan under kallare månader kunna använda detta. Syftet med projektet har varit att bygga en prototyp för styrning och övervakning av ett system. Med detta projekt vill vi visa en lösning på en prototyp som kan fungera som utvecklingsplattform för beställaren. Kommunikation mellan aktuatorer, sensorer och styrenhet görs via en CAN-buss. Temperaturensorernas använder sig av en One-wire buss och dess värden sparas och kan avläsas på en webbplats. Resultatet visar att övervakning av sensordata och reglering av aktuatorer fungerar. Teoretiskt sett är prototypen utformad för att expanderas till en verklig applikation.
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Tica, Amer, and Anton Lewin. "Riskanalys - En studie av BTHs säkerhet." Thesis, Blekinge Tekniska Högskola, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-10517.
Повний текст джерелаАнотація:
Sammanfattning Bakgrund: Det som väckte vårt intresse med att just inrikta oss på Blekinge Tekniska Högskola var ett fall från 2011 i Januari då en knivbeväpnad mördare tog sig in på skolan och rörde sig fritt utan att många i personalen visste om det. Det är sådana risker som ofta förbises vid en riskanalys och vi ville undersöka vilka åtgärder som gjorts gällande säkerheten och hur man arbetat och förbättrat sitt säkerhetssystem så detta inte sker igen Syfte: Syftet med studien är att göra en riskanalys och behandla hur säkerheten på högskolan ser ut samt om det är något speciellt område just denna högskola bör fokusera på och varför, samt hur man bemöter och evaluerar risker i dagsläget. Metod: Vårt metodval bygger på en blandning av kvalitativ och kvantitativ metod. Resultatet har baserats på våra egen uppfattning och vi har skapat vissa teorier under arbetets gång. Vi fokuserar framför allt på varför det är och bakomliggande orsaker vilket ligger mer i det kvalitativa medan vi samtidigt på grund av att den mänskliga faktorn spelar stor roll i vårt arbete även måste skriva om beteende som dras lite mer åt det kvantitativa hållet Resultat: Det resultat vi har kommit fram till har vi valt att presentera i form av en riskanalys som hittas mot slutet av uppsatsen. Denna innehåller alla de risker vi tyckt varit värda att behandla samt en numrering gällande hur mycket pengar och tid man ska lägga ner på just den risken, numreringen sträcker sig från 1(inte värd att kolla på) - 25(mycket värd att kolla på) Slutsats: För att kunna avgöra om BTH:s säkerhet för närvarande har några brister så har vi i vår slutsats och avslutande diskussion gjort en jämförelse mellan alla risker vi fick fram från vår riskanalys och hur dessa risker kan åtgärdas, i förhållande till hur BTH:s nuvarande säkerhet ser ut. Baserat på denna jämförelse har vi sedan kunnat utläsa vilka svagheter som finns inom verksamheten och utifrån detta har vi föreslagit våra egna rekommendationer gällande hur säkerheten kan förbättras.
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Persson, Jesper, and Kristoffer Dahl. "Control and Monitoring of a BTES-System." Thesis, Högskolan i Halmstad, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-30304.
Повний текст джерелаАнотація:
Termisk energi som solfångare producerar kan lagras i Borehole Thermal Energy Storage, BTES, när efterfrågan är låg, för att sedan användas när efterfrågan är hög. Målet med detta examensarbete är att utveckla en skalbar systemarkitektur för styrning och monitorering av en BTES prototyp, där ringarna som borrhålen utgör är indelade i olika temperaturhierarkier. De ringar som ligger närmare centrum av borrhålen har högre temperaturhierarki än de som ligger längre ut. Driftinformation från systemet ska kunna följas på en webbplats och temperaturdata från systemet ska sparas undan för lagring. Datakommunikationen består av en One-Wire buss som innehåller temperatursensorer och ett CAN-buss system för datakommunikation mellan sensor/aktuator-noder och server-nod. Utifrån sensordata bestäms reglering av ventiler. Driftinformation lagras i en databas och från denna databas presenteras informationen på en hemsida. Hemsidan innehåller en överblick av brunnparken där temperaturen i varje brunn kan utläsas. Regleralgoritmen uppfyller den sökta temperaturhierarkin där de högsta temperaturerna ska vara i centrum av brunnparken. Prototypen fungerar som en utvecklingsplattform och demonstrerande prototyp.Thermal energy produced from solar collectors can be stored in Borehole Thermal Energy Storage, BTES, when demand is low for later usage when demand is high. The aim of this thesis is to develop a scalable system architecture for control and monitoring of a BTES prototype.The BTES prototype consist of 13 boreholes configured in a hierarchically manner in two circles and one core. The core is of the highest priority. The operational information is displayed on a website and stored in a database.The data communication consist of two One-wire buses and one CAN bus. The temperature sensors are connected to the One-Wire buses. The CAN bus consist of sensor/actuator nodes and a server node. Based on sensor data, a control loop configures the actuators. Operational data is stored in a database and visually presented on a website. The website displays an overview of all the boreholes where all of the sensors data can be read. The control algorithm runs successfully according to its hierarchically priorities. The prototype works as a developement platform and a demonstrating prototype.
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Majava, J. (Jani). "Ikiroudan mallintaminen Kilpisjärvellä BTS-metodilla." Master's thesis, University of Oulu, 2014. http://urn.fi/URN:NBN:fi:oulu-201402271141.
Повний текст джерелаАнотація:
Ilmaston lämpenemisen, Jäämeren sulamisen ja raaka-ainevarojen vähentymisen sekä kasvavan kulutuksen seurauksena pohjoisten alueiden hyödyntämättömät ja löytymättömät resurssit ovat kasvavan kiinnostuksen kohteena. Tämän takia on tärkeää ymmärtää pohjoisten alueiden ilmiöitä. Koska lähes 25 prosenttia pohjoisen pallonpuoliskon maa-alasta on ikirouta-alueita, ovat ikiroutaan liittyvien prosessien ymmärtäminen, ikiroudan kartoittaminen ja mallintaminen tärkeitä. Ikirouta onkin otettava huomioon kaikissa pohjoisille alueille kohdistuvissa projekteissa.
Tämän tutkimuksen tarkoituksena on selvittää ikiroudan alueellinen esiintyminen Kilpisjärvellä ja määrittää ikiroudan alueelliseen esiintymiseen vaikuttavat ympäristötekijät BTS-metodiin pohjautuvalla tilastollisella mallintamisella. Lisäksi työssä arvioidaan menetelmän soveltuvuutta Suomen Lapin olosuhteisiin. Tämä on ensimmäinen tutkimus, jossa ikiroutaa mallinnetaan Suomessa BTS-metodia hyödyntäen. Tutkimusaineisto koostuu maastoaineiston lisäksi satelliittikuvista ja digitaalisesta korkeusmallista johdetuista muuttujista. Maastossa on mitattu 435 pisteestä hangenalaiset maanpinnan lämpötilat, jotka tarpeeksi alhaisina kertovat ikiroudan läsnäolosta. Ikiroudan alueellista esiintymistä ja sitä selittäviä tekijöitä on mallinnettu lineaarisen regression, yleistetyn lineaarisen mallin (GLM) ja yleistetyn additiivisen mallin (GAM) avulla. Mallien tuottamien ennusteiden pohjalta on tehty ikiroudan alueellista esiintymistä Kilpisjärvellä kuvaavat ennustekartat.
Ikiroutaa selittäviksi tekijöiksi valikoituivat lineaarisessa regressiomallissa korkeus ja aspekti, yleistettyyn lineaariseen malliin valikoituivat korkeus, vuotuinen säteily ja sen toisen asteen polynomifunktio, maaston kaarevuus sekä rinteen kaltevuus ja yleistettyyn additiiviseen malliin valikoituivat korkeus, vuotuinen säteily, maaston kaarevuus, NDVI-kasvillisuusindeksi, aspekti ja rinteen kaltevuus. Kaikki mallit sopivat aineistoon, koska residuaalit olivat normaalisti jakautuneita. Mallien selitysaste oli keskimäärin 47,5 prosenttia.
Tulosten perusteella Kilpisjärven alue kuuluu sporadisen ikiroudan alueeseen ja ikirouta on todennäköisintä tuntureiden lakialueilla ja pohjoisrinteillä. Ikirouta on mahdollista tuntureiden alemmilla rinteillä ja osassa paljakkaa, mutta tunturikoivikoissa ja alhaisten korkeuksien paljakalla ikiroutaa ei esiinny. Tärkeimmät ikiroudan esiintymisen alueellista vaihtelua Kilpisjärvellä selittävät ympäristötekijät ovat kasvillisuus, maaperän materiaali, aspekti ja korkeus. Korkeus vaikuttaa ikiroudan alueelliseen esiintymiseen muiden sen funktiona muuttuvien ympäristötekijöiden kuten kasvillisuuden, lämpötilan ja tuulisuuden kautta. Maastomittausten ja tutkimustulosten perusteella voidaan sanoa, että BTS-metodia voidaan soveltaa Suomen Lapin olosuhteissa ikiroudan mallintamiseen ja kartoittamiseen.
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Bäckström, Johan. "Energioptimering industritvätt : Energibesparing BTS Umeå." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-66003.
Повний текст джерелаАнотація:
Med rådande klimatsituation är ett kontinuerligt arbete med hur man använder energi och hur denproduceras viktigt. Berendsen Textil Service AB (BTS) är ett företag som kontinuerligt arbetar medförbättring för att uppnå sina satta verksamhets- och miljömål. Som ett led i detta förbättringsarbetegenomfördes arbetet som ligger till grund för denna rapport.BTS Umeå var i startgroparna på ett projekt för installation av reningsverk och ville passa på attgenomföra ytterligare förbättringsarbete. De önskade hjälp med att fastställa möjligheten tillenergiåtervinning ur deras processvatten.Arbetet har genomförts genom analys av BTS Umeås förbrukningsdata som används för internrapportering och statistik. Temperaturer hos processvattnet vid olika punkter i flödet har uppmätts vidliknande anläggningar som redan använder sig av det tilltänkta reningsverket. Med hjälp av beräkningarbaserat på dessa värden har energiåtervinningspotentialen fastställts. Dessa beräkningar visar att 860kWh per dag finns att tillgå en energiåtervinningsåtgärd. Tre alternativa lösningar har analyserats -återvinning av processvatten efter rening, energiåtervinning av värme från processvatten innan reningmed värmeväxlare, samt en kombination av dessa två.Resultatet av dessa analyser visar att en energibesparing upp mot 21 % av den i anläggningenkonsumerade eldningsoljan är möjlig med alternativ som finns beskrivet i denna rapport vilketmotsvarar ca. 61 l eldningsolja E10 per dag. Denna besparing fås genom återvinning av renat varmtprocessvatten bland annat med hjälp av rörvärmeväxlare. Rörvärmeväxlaren valdes på grund av att denhar tillräcklig god effektivitet samtidigt som underhållet av värmeväxlaren skulle vara enkelt och billigt
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Yao, Yimei Carleton University Dissertation Computer Science. "BTS: a new distributed data structure." Ottawa, 1993.
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Silva, Jacqueline Pereira Figueiredo Ferreira da. "Caracterização de compostos aromáticos em gasolina comercial." Universidade do Estado do Rio de Janeiro, 2009. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=2833.
Повний текст джерелаАнотація:
A contaminação do ar e do meio ambiente por combustíveis derivados de petróleo tem sido objeto de crescente pesquisa no Brasil. Dentre os tipos de poluição ao meio ambiente, a poluição atmosférica é a que causa mais incômodo à população. Esta exerce efeitos sobre a saúde humana, causando desde simples irritações até câncer de pulmão. Dos poluentes mais perigosos encontrados nesses ambientes, são destaques os hidrocarbonetos e os compostos monoaromáticos como o benzeno, tolueno e xilenos (BTX), presentes nesses combustíveis, que são extremamente tóxicos à saúde humana. Para controle desses compostos orgânicos voláteis, é necessário quantificá-los e compará-los aos valores limites de tolerância legislados no Brasil. A utilização da técnica de cromatografia gasosa e da técnica de espectroscopia por infravermelho permite realizar essa tarefa de maneira relativamente simples e rápida. Portanto o objetivo deste trabalho foi apresentar a composição química de amostras de gasolina do tipo C comercializadas nos postos revendedores da Região Metropolitana do Estado do Rio de Janeiro. Foram feitas análises quantitativas dos principais grupos químicos (parafínicos, olefínicos, naftênicos e aromáticos) e etanol por Cromatografia Gasosa de Alta Resolução e da composição de benzeno, tolueno e xileno (BTX) pela técnica de absorção no infravermelho. Os resultados foram comparados com os limites dados pela especificação da ANP (Portaria n 309) para a qualidade da gasolina, com o objetivo de se verificar se estão em conformidade com este agente regulamentador. Os resultados mostraram que todos os teores encontrados de olefínicos e aromáticos foram abaixo do limite especificado. Alguns postos apresentaram os teores de benzeno acima do limite especificado, indicando um nível de ação por parte da ANP principalmente pela ação tóxica do benzenoThe air contamination and the environment by fuels derived from crude oil has been object of increasing research in Brazil. Amongst the types of pollution to the environment, the atmospheric pollution is the one that cause more discomfort to the population. This exerts effects on the human health, causing since simple irritations until lung cancer. Among the most dangerous pollutants found in these environments are prominences the aliphatic hydro carbons and monoaromatic hydrocarbons compounds as benzene, toluene and xylems (BTX), present in these fuels that are extremely toxic to the human health. To control these volatile organic compounds, is necessary to quantify and to compare them with the tolerance limits value legislated in Brazil. The gas chromatography and infra-red ray spectroscopy techniques utilization allows realizing easily and fast these tasks. Therefore the objective of this work was to present the type C gasoline samples chemical composition commercialized on the gas station of the metropolitan region on Rio de Janeiro state. Had been made quantitative analyses for the main chemical groups (paraffins, olefins, naphthenics and aromatics) and ethanol by high resolution Gas Chromatography and the composition for benzene, toluene and xylem (BTX), by infra-red ray absorption technique. The results had been compared with the limits given by ANP specification (Portaria n 309) for the gasoline quality, with the objective to verify if they are in compliance with this regulatory agent. The results had shown that all amount founded for aromatics and olefinics had been below of the specified limit. Some gas station had presented amount for benzene above of the specified limit, indicating that ANP need to take some actions toward these gas station, mainly for the benzene toxicity action
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Milesson, Joel, and Erika Abrahamsson. "Geoenergilager Xylem : Visualisering och lönsamhet." Thesis, Linnéuniversitetet, Institutionen för bygg- och energiteknik (BE), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-27037.
Повний текст джерелаАнотація:
Inom svensk process- och tillverkningsindustri finns det stora mängder spillvärme som sällan kommer till användning. Att hitta olika tekniska lösningar för att effektivt tillvarata denna spillvärme skapar både nytta ur ett hållbart perspektiv samt ur ett ekonomiskt perspektiv för företaget. I denna rapport presenteras en utarbetad beräkningsmodell i Excel. Beräkningsmodellen används för att uppskatta lönsamheten för anläggning av ett högtemperaturlager i berggrunden. Excel-filen ska kunna användas för företag som en första uppskattning om ett borrhålslager är ett alternativ för tillvaratagande av spillvärme. Utformningen av beräkningsmallen utgick från Xylems högtemperaturlager i Emmaboda. Beräkningsmallen testades på Xylems borrhålslager. Resultatet visar att 2166 MWh/år kan tas ut från lagret, vilket stämmer överens till 83 % med Xylems egna beräkningar. Borrhålslagrets verkningsgrad beräknades till 65 % vilket kan jämföras med de 68 % som Xylem kalkylerat med. Nyckelord: Borrhålslager, UTES-system, BTES-system, HT-BTES-system, geoenergi, spillvärme.
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Almeida, Kelly Cristina Santana de. ""Avaliação da contaminação da água do mar por Benzeno, Tolueno e Xileno na região de Ubatuba e estudo da degradação destes compostos por radiação ionizante"." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-22052007-143631/.
Повний текст джерелаАнотація:
O principal problema relativo aos acidentes com vazamentos de óleos combustíveis nos ambientes marinhos e costeiros é a contaminação pelos compostos benzeno, tolueno e xileno, (BTX), que possuem toxicidade elevada. O objetivo deste trabalho foi avaliar a contaminação da água do mar por BTX na região de Ubatuba, SP, entre 23º26S e 23º46S de latitude e 45º02W e 45º11W de longitude, que é uma área de transporte e produção de petróleo e estudar a eficiência da remoção destes compostos pela exposição à radiação ionizante proveniente de uma fonte de 60Co. A metodologia analítica utilizando o sistema de concentração Purge and Trap e o cromatógrafo CG-DIC, apresentou maior sensibilidade em água do mar do que o sistema de concentração headspace associado ao cromatógrafo CG-EM, com limite mínimo de detecção, LMD, de 0,50 μg/L de benzeno, 0,70 μg/L de tolueno e 1,54 μg/L de xileno com uma variabilidade experimental (N=10) de cerca de 15%. Enquanto que o sistema CG-EM apresentou um LMD de BTX em água do mar de 9,30 mg/L para o benzeno, 8,50 mg/L para o tolueno e 9,80 mg/L para o xileno, com uma variabilidade experimental calculada nas mesmas condições de cerca de 10%. Foram realizadas quatro coletas de novembro de 2003 a julho de 2005 e a concentração de benzeno na água do mar variou de 1,0 μg/L a 2,0 μg/L, a de tolueno variou de <0,70 μg/L a 3,24 μg/L e para o xileno o valor máximo detectado foi de 2,92 μg/L. No caso das amostras de água do mar contaminadas com padrões de BTX e expostas à radiação ionizante, a eficiência de remoção para o benzeno foi menor do que para os outros compostos considerando-se as mesmas concentrações, a taxa de remoção variou de 10% a 40% para dose absorvida de 20kGy e concentrações de 35,1 mg/L a 70,2 mg/L, respectivamente. O tolueno apresentou 20% a 60% de remoção para concentrações similares, mas com 15kGy de dose absorvida. Finalmente, o xileno foi removido com eficiência de 20% a 80% e 15 kGy de dose absorvida.A major concern with leaking petroleum is the environmental contamination by the toxic and low water-soluble components such as benzene, toluene, and xylenes (BTX). These hydrocarbons have relatively high pollution potential because of their significant toxicity. The objective of this study was to evaluate the contamination of seawater by the main pollutants of the output and transport of petroleum, such as benzene, toluene, and xylene, and their removal by the exposure to the ionizing radiation. The studied region was Ubatuba region, SP, between 23º26S and 23º46S of latitude and 45º02W and 45º11W of longitude, area of carry and output of petroleum, and samples were collected from November, 2003 to July, 2005. For BTX in seawater analysis, the Purge and Trap concentrator with FIDGC detector showed significantly higher sensibility than Head Space concentrator with MSGC detector. The minimal detected limits (MDL) obtained at FIDGC were of 0.50 μg/L for benzene, 0.70 μg/L for toluene, and 1.54 μg/L for xylene, and the obtained experimental variability was 15%. While the concentrator type Headspace system with MS detector showed higher MLD, about of 9.30 mg/L for benzene, 8.50 mg/L for toluene, and 9.80 mg/L for xylene, and 10% of experimental variability. In the studied area the benzene concentration varied from 1.0 μg/L to 2.0 μg/L, the concentration of toluene varied from < 0.70 μg/L to 3.24 μg/L and the maximum value of xylene observed was of 2.92 μg/L. The seawater samples contaminated with BTX standard and exposed to ionizing radiation using a source of 60Co, presented a removal from 10% to 40% of benzene at 20 kGy absorbed doses and concentration of 35.1 mg/L and 70.2 mg/L, respectively; from 20% to 60% of toluene removal with 15 kGy absorbed dose and from 20% to 80% of xylene with 15 kGy absorbed dose in similar concentrations.
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Riquelme, Rafael, and Patricio Moisan. "BTS CHILE SPA : (Baby travel service Chile)." Tesis, Universidad de Chile, 2018. http://repositorio.uchile.cl/handle/2250/168292.
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TESIS PARA OPTAR AL GRADO DE MAGÍSTER EN ADMINISTRACIÓNRiquelme, Rafael, [Parte I], Moisan, Patricio, [Parte II]
En la actualidad, Chile posee un parque automotriz cercano a los 5 millones de automóviles y sólo cerca de un 75% de los conductores utilizan el cinturón de seguridad de manera habitual. Para el caso del uso de sistemas de retención infantil (conocidos como sillas de seguridad) la tasa de uso baja a un 49% a pesar de ser un mecanismo de seguridad pasivo altamente efectivo. Esto deja en evidencia los rasgos conductuales de los chilenos que no están alineados con aspectos de seguridad. De acuerdo a la investigación realizada, la tasa de uso de sillas de seguridad tiene una alta correlación con los grupos socioeconómicos (GSE) teniendo una alta adhesión en los grupos altos y baja adhesión en los grupos más vulnerables. Con este antecedente, BTS Chile identificó que tanto los rasgos culturales como económicos son las principales causantes de la baja tasa de uso por lo cual se presenta con una propuesta de valor socioambiental que busca satisfacer las necesidades tanto de los consumidores conscientes como de los consumidores con poder adquisitivo más limitado. En base a lo anterior, BTS propone un modelo de negocio con foco en servicios que viene a desmarcarse en un mercado caracterizado por la venta directa a través del retail o de canales propios (tiendas especializadas). Lo anterior siendo factible gracias a la integración de un dispositivo de detección y registro de impactos en las sillas de seguridad que permite garantizar la integridad de productos usados en el caso que no hayan pasado por algún siniestro. Esta innovación permite comercializar de manera cíclica productos reacondicionados hasta cumplir el periodo de vigencia de las sillas (10 años aproximadamente) obteniendo beneficios significativos al promover la eliminación del mercado negro y llegar a los grupos económicos vulnerables con productos de primera calidad a bajos precios. Adicionalmente, las sillas que hayan pasado por algún siniestro se recuperarán para ser recicladas para contribuir al cuidado medioambiental. El modelo planteado por BTS Chile considera marginar principalmente por la venta de productos nuevos a los GSE altos (ABC1 principalmente) y de esta manera subvencionar fuertemente los precios de venta a GSE vulnerables, así como las campañas de ayuda social (entrega gratuita) La componente social y ambiental con la cual BTS Chile plantea su modelo de negocio permite que esté certificada como empresa B y potencia de esta manera su estrategia de posicionamiento dentro de los consumidores conscientes.
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Geddes, Patrick H. "Displaying and improving run-length encoded images on a BTOS system." Master's thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-02162010-020208/.
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Chihara, Kazuyuki, Ryota Suzuki, and Naoki Omi. "Diffusion of BTX in MSC5A in supercritical CO2." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-194790.
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Minatti, Gheise. "Biodegradação dos compostos BTX de efluente petroquímico sintético." reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/92450.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Química, Florianópolis, 2009Made available in DSpace on 2012-10-24T09:00:12Z (GMT). No. of bitstreams: 1 272193.pdf: 1992150 bytes, checksum: 58b17c6c8820a6878faa785dc6f6abe2 (MD5)
Os hidrocarbonetos aromáticos benzeno, tolueno e xilenos, coletivamente conhecidos como BTX são compostos tóxicos presentes em derivados de petróleo, como a gasolina, e utilizados em larga escala nas indústrias químicas e petroquímicas. Estes compostos quando liberados no meio ambiente contaminam o solo e as águas subterrâneas, podendo inviabilizar a exploração de aqüíferos, que atualmente representam uma fonte alternativa de água potável. Portanto, é fundamental a pesquisa de processos de biodegradação, particularmente quando múltiplos substratos estão presentes no sistema. Neste trabalho investigou-se a cinética de biodegradação dos compostos BTX, individualmente e em mistura. Para tanto, o desempenho de diversos modelos não-estruturados de crescimento microbiano, baseado na cinética no nível da população, foi avaliado utilizando-se dados experimentais obtidos em laboratório. Foram aplicados os modelos de Monod e Andrews à cinética de biodegradação individual dos substratos. Igualmente, as equações aplicadas à cinética de biodegradação da mistura BTX foram resolvidas considerando os modelos de inibição competitiva, acompetitiva e não-competitiva. Os parâmetros cinéticos dos modelos de único e múltiplos substratos foram obtidos utilizando o software STATISTICA 7.0, que possibilitou realizar a regressão não linear dos dados. A biodegradação individual dos substratos BTX foi adequadamente representada pelos modelos de Andrews e Monod. A cinética de biodegradação dos compostos BTX, comprova-se que a biodegradação do tolueno é a mais rápida seguida do benzeno e o-xileno, respectivamente. Na biodegradação da mistura binária BT e BX o modelo de Inibição Acompetitiva foi o que melhor apresentou concordância com os resultados experimentais. Para a biodegradação binária TB e TX prevaleceu como melhor modelo Inibição Competitiva. Na concentração inicial de 50 mg/L de o-Xileno na presença de benzeno houve Inibição Não Competitiva e o mesmo comportamento se deu com o tolueno. Na biodegradação tricomponente BTX em diferentes concentrações o modelo de Inibição Não Competitiva, Acompetitiva e Competitiva foram verificados. De forma geral, tanto para a biodegradação de um único substrato, quanto para múltiplos substratos, o comportamento cinético será diferente para cada caso, concordando com o fato de que, a mistura de culturas microbianas utilizada na biodegradação, pode apresentar múltiplos caminhos para a biodegradação dos compostos BTX.
The aromatics hydrocarbons usually known as BTX (benzene, toluene and xylenes isomers) are toxics compounds presented in many petroleum products, such as gasoline, and are also widely used in chemical and petrochemical industries. When these compounds are released in the environment a contamination of the soil and the groundwater took place. As a result, the use of the aquifers becomes impossible. Groundwaters nowadays represent an alternative potable water source in many countries. Therefore, it#s crucially important to study the biodegradation process, in particular when multiple substrates are presented in the system. In this work, the kinetics of BTX biodegradation was studied, individually and as in mixture. Hence, the performance of the different microbial growth unstructured models, based on the population level kinetics were investigated by using experimental data from laboratory. Were apply the Monod and Andrews models to describe an individual substrates biodegradation kinetics. Similarly, the applied equations describing mixture substrates biodegradation kinetics were solved by using the competitive, noncompetitive and uncompetitive inhibitions models. The kinetic parameters to the models of single and multiple substrates have been obtained using the STATISTICA 7.0 software, which allows performing the nonlinear regression of data. The BTX individual biodegradation substrates was adequately represented by the models of Monod and Andrews. The kinetics of biodegradation of BTX compounds, shows that the biodegradation of toluene is faster than benzene and o-xylene, respectively. Binary mixture in the biodegradation of BT and BX Acompetitiva Inhibition of the model was presented the best agreement with the experimental results. To biodegradation and binary TB TX prevailed as the best competitive inhibition model. In initial concentration of 50 mg / L of o-xylene in the presence of benzene inhibition was not competitive and the same behavior occurred with toluene. Tricomponente BTX biodegradation in different concentrations in the model uncompetitive inhibition, and competitive Acompetitiva were verified. In general, both biodegradation of a single substrate, and for multiple substrates, the kinetic behavior is different in each case, agreeing with the fact that mixture microbial cultures used in biodegradation, can submit multiple pathways for biodegradation of BTX compounds.
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Chihara, Kazuyuki, Ryota Suzuki, and Naoki Omi. "Diffusion of BTX in MSC5A in supercritical CO2." Diffusion fundamentals 3 (2005) 17, S. 1-2, 2005. https://ul.qucosa.de/id/qucosa%3A14305.
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abbes, cyrine. "Online Digital Media Practices on Twitter By Korean Pop Idol BTS and Fans: A Case on BTS (방탄소년단) and their Fans". Thesis, Uppsala universitet, Institutionen för informatik och media, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-388680.
Повний текст джерелаАнотація:
The research conducted focused on the media practices by a South Korean band « BTS » and the named fandom « A.R.M.Y ». Through the use of Twitter, the research consisted in making use of BTS’s Twitter posts to study what they are doing on social media in order to engage fans, as well as the type of practices that are being executed. The second part of the study investigated the fandoms’ interaction, participation, and online engagement in regard to the media content tweeted by the south Korean band. Mix methods were used in order to answer the three research questions that were presented for this research. An analysis of media practices was conducted through a content analysis then followed by an online survey. The analysis highlighted that shared practices and regular media use were an important factor in the creation of a participatory culture. Culture was also shown to be an important component to the generation of fan engagement and artist interaction with their respective fandom. In addition, through fans high participation in online activities, the investigation was able to demonstrate that fans developed shared practices and shared identities, which were emerged from their activities. Furthermore, BTS members have shown that their cultural habits were important for engaging fans. Overall, the results of this study concluded that media practices are various and are executed in ways that allow the South Korean band to keep an online relationship with their fans through diverse media content that is published on their own personal managed Twitter account. In response to that, fans have shown a constant interactions and engagements by liking, retweeting, commenting to the bands’ tweets, along with other different activities that have been demonstrated in the analysis chapter. Keywords: Social Media, K-pop, Fandom, Digital media practices, Participatory culture, engagement and interaction, Twitter
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Johnson, Earl E. "Practitioners Give High Marks to Open-canal Mini-BTEs on User Benefit." Digital Commons @ East Tennessee State University, 2008. https://dc.etsu.edu/etsu-works/1967.
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What do hip-huggers, HEMI engines, and behind-the-ear (BTE) hearing aids have in common? Not a whole lot except that all three were trendy in the 1960s and 1970s, then fell into decline, and now, in the new millennium, are selling like those proverbial hotcakes! They have also all come back in somewhat different forms. Chrysler's new HEMI engine, introduced in 2002, is a little smaller than that of yesteryear. The old hip-huggers have been reincarnated as “low-rise jeans.” And the BTE's return to dominance of the hearing aid market has been fueled by the appearance of smaller instruments with open-canal (OC) fittings, beginning in 2003 with the GN ReSound Air®. Today, every manufacturer offers smaller BTEs, mostly fitted with an open canal, and often categorized under new names, such as post-auricular-canal, over-the-ear, and mini- and micro-BTEs. This new breed of products is also showing up in an amazing range of shapes and colors, as that old industry dream of stylish hearing aids is finally coming true. The Hearing Industries Association (HIA), the main source of U.S. market sales data, recently reported that 51.45% of all hearing aids sold in 2007 were of some BTE style. However, it remains uncertain how much of the boom in BTE sales has resulted from smaller open-fit BTE hearing aids, herein referred to as OC mini-BTEs. To find out the extent of the OC mini-BTE boom—and also what dispensers and their patients think of this product type—the 2008 Hearing Journal/AudiologyOnline (HJ/AO) survey included a special section of 10 questions for audiologists, hearing instrument specialists, and other hearing professionals about their experiences with and opinions on these devices. The survey also included questions on many other topics, which will be reported on next month. But this Cover Story focuses on what our survey learned about OC mini-BTEs—their popularity and their perceived benefits and drawbacks. First though, here's a quick look at how the survey was conducted and who took part.
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Leeder-Kamanda, Götz. "Das Verhalten von BTX-Aromaten in der ungesättigten Bodenzone." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2009. http://nbn-resolving.de/urn:nbn:de:bsz:105-3979693.
Повний текст джерелаАнотація:
Es wurden Versuche für die ungesättigte Zone duchgeführt, um das Verhalten kleinerer Einträge an Benzen, Toluen und Xylen im Oberboden anschätzen zu können. In einem Vorversuch wurde der Verteilungskoeffizient Gas-Wasser für verschiedene Wässer bestimmt. Der Einfluss der Temperatur hatte einen größeren Einfluss als der Chemismus des Wassers. Die Sorption wurde ermittelt und zeigte sich als ein über sechs Größenordnungen linearer Prozess. Sie ist abhängig vom Humusgehalt. Versuche zur Desorption zeigen Unterschiede zwischen den Aromaten. Xylen desorbiert am langsamsten. Fünf, z.T. mehrmonatige Versuche mit einem großen Laborlysimeter (60 cm Durchmesser, 2 m Länge) zeigten, dass die Korngröße die Diffusion und dichtebedingte Konvektion der gasförmigen Aromaten beeinflusst. Diese Vorgänge sind für den schnellen Transport verantwortlich. Das Sickerwasser bewegt sich deutlich langsamer, transportiert aber die größeren BTX-Mengen. Humushaltige Böden können den Transport in tiefere Bereiche aufgrund von Sorption deutlich reduzieren. Mikrobieller Abbau lässt sich über den Sauerstoffverbrauch nachweisen.
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Fandary, Mohamad S. H. "BTX extraction by sulfolane in a mixer-settler cascade." Thesis, Aston University, 1988. http://publications.aston.ac.uk/9704/.
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The literature relating to the extraction of the aromatics, benzene, toluene and xylene (BTX) using different commercial solvents, and to mixer-settler design and performance, has been reviewed. Liquid-liquid equilibria of the ternary systems: hexane-benzene-sulfolane, n-heptane-toluene-sulfolane, and octane-xylene-sulfolane were determined experimentally at temperatures of 30oC, 35oC, and 40oC. The work was then extended to a multicomponent system. The data were correlated by using Hand's method and were found to be in a good agreement with theoretical predictions using the UNIFAC method. A study was made of the performance of a 10-stage laboratory mixer-settler cascade for the extraction of BTX from a synthetic reformate utilizing sulfolane as a solvent. Murphree stage efficiency decreased with stage number but 99% extraction was achievable within 4 stages. The effects of temperature, phase ratio, and agitator speed were investigated. The efficiency increased with agitator speed but > 1050 rpm resulted in secondary haze formation. An optimum temperature of 30oC was selected from the phase equilibria; the optimum solvent: feed ratio was 3:1 for 4 stages. The experimental overall mass transfer coefficients were compared with those predicted from single drop correlations and were in all cases greater, by a factor of 1.5 to 3, due to the surface renewal associated with drop break-up and coalescence promoted by agitation. A similar investigation was performed using real reformate from the Kuwait Oil Company. The phase ratios were in the range 0.5 to 1 to 3.25 to 1, the agitator speed 1050 rpm, and the operating temperature 30oC. A maximum recovery of 99% aromatics was achieved in 4 stages at a phase ratio of 3.25 to 1. A backflow model was extended to simulate conditions in the mixer-settler cascade with this multicomponent system. Overall mass transfer coefficients were estimated by obtaining the best fit between experimental and predicted concentration profiles. They were up to 10% greater than those with the synthetic feed but close agreement was not possible because the distribution coefficient and phase ratio varied with stage number. Sulfolane was demonstrated to be an excellent solvent for BTX recovery and a mixer-settler cascade was concluded to be a technically viable alternative to agitated columns for this process.
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Bedin, Sidmara 1988. "Preparação e caracterização de argila oganofílica para adsorção de BTX." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266118.
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Orientadores: Meuris Gurgel Carlos da Silva, Onelia Aparecida Andreo dos SantosDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: Diariamente, uma grande quantidade de fluxos de água sofre contaminação por compostos orgânicos como, por exemplo, o benzeno, tolueno e xileno (BTX), os quais são compostos tóxicos e nocivos ao meio ambiente e aos seres humanos. Sendo assim, o estudo de técnicas de remoção e tratamento desses poluentes vem se tornando tema de muitas pesquisas. A adsorção tem se mostrado uma técnica bastante eficiente, pois atende aos limites da legislação, apresenta baixo consumo energético e custo de processo, ainda mais quando se faz uso de um adsorvente alternativo, como é o caso da argila organofílica. Nesse trabalho foi proposto avaliar a argila esmectítica sódica nacional Fluidgel, na forma natural e organofilizada, como materiais adsorventes alternativos na remoção dos compostos orgânicos BTX de soluções aquosas, em ensaios em sistema batelada e em sistema dinâmico. A argila organofílica foi preparada a partir da argila comercial e do sal quaternário de amônia HDTMA e se verificou a capacidade de troca catiônicas dos adsorventes. Foram realizadas técnicas de caracterização com a finalidade de determinar a área superficial do material, estrutura de poros, estrutura cristalina, morfologia de superfície, composição química, perda de massa e água e identificação de grupos funcionais de superfície. Testes preliminares comprovaram o caráter hidrofóbico da argila organofílica e sua afinidade por compostos orgânicos, bem como o caráter hidrofílico da argila comercial. Ensaios cinéticos de pH mostraram que o mesmo não afeta de maneira significativa o processo de adsorção. Os ensaios cinéticos de adsorção realizados em sistema batelada alcançaram o equilíbrio em 3h e apresentaram porcentagens de remoção de poluente superiores a 90%, com concentração inicial de 1,09 mmol/L. Os modelos cinéticos analisados foram o de pseudoprimeira ordem, pseudossegunda ordem e o de difusão intrapartícula, sendo que o modelo de pseudossegunda ordem melhor descreveu os dados experimentais. Para as isotermas de equilíbrios, testou-se as temperaturas de 35, 25 e 15 oC, sendo a maior capacidade de remoção com a maior temperatura, indicando que a adsorção nesse caso é de natureza endotérmica. Os modelos de isotermas avaliados foram Langmuir, Freundlich, Sips, DSL, MSAM e D-R, porém apenas o modelo de D-R descreveu de maneira satisfatória os dados experimentais. Pela análise dos parâmetros termodinâmicos, verificou-se que o processo de adsorção em estudo é espontâneo, favorecido a altas temperaturas e que possivelmente ocorre fisissorção. Devido à alta volatilidade dos compostos BTX, foi feita uma adaptação na adsorção em sistema dinâmico através de coluna de leito fixo e se realizou um ensaio cinético em leito de adsorção. A ordem de remoção dos compostos orgânicos, para ambas as argilas, foi xileno > tolueno > benzeno
Abstract: Daily a large amount of water flows suffers contamination by organic compounds as, for example, benzene, toluene and xylene (BTX), which are toxic compounds and harmful to the environment and to humans. Thus, the study of techniques for removal and treatment of these pollutants has become the subject of much research. The adsorption has proven to be a very effective technique because it meets the limits of the law, has low energy consumption and process cost, further when it makes use of an alternative adsorbent, as is the case with organoclay. In this study, it was proposed evaluate the national sodium smectite clay Fluidgel , in the natural and organophilizated form, as an alternative adsorbent material to the removal of organic compounds BTX from aqueous solutions in batch and dynamic system essays. The organoclay was prepared from the commercial clay and the quaternary ammonium salt HDTMA and it was verified the cationic exchange capacity of the adsorbents. Were performed characterization techniques in order to determine the surface area of the material, pore structure, crystal structure, surface morphology, chemical composition, mass and water loss and identification of surface functional groups. Preliminary tests confirmed the hydrophobic character of the organoclay and their affinity for organic compounds and the hydrophilic character of the commercial clay. pH kinetic experiments showed that the same does not affect significantly the adsorption process. Kinetic assays of adsorption performed in batch system reached equilibrium in 3 hours and showed pollutant removal percentages greater than 90%, with an initial concentration of 1.09 mmol/L. The kinetic models analyzed were the pseudo first order, pseudo second order and the intraparticle diffusion, being that the pseudo second order model best described the experimental data. For the equilibrium isotherm, was tested at temperatures of 35, 25 and 15 °C, being the largest removal capacity with the greatest temperature, indicating that the adsorption of this case is endothermic in nature. The isotherm models evaluated were Langmuir, Freundlich, Sips, DSL, MSAM and D-R, but only the D-R model described satisfactorily the experimental data. By the analysis of the thermodynamic parameters, it was found that the adsorption in study is spontaneous and favorable at high temperatures and that possibly occurs physisorption. Due to the high volatility of BTX compounds, it was made an adaptation to dynamic adsorption system through fixed bed column and a kinetic assay was carried out in adsorption bed. The order of removal of organic compounds for both clays was xylene > toluene > benzene
Mestrado
Engenharia Química
Mestra em Engenharia Química
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Zuhadmono, Alvia. "Transmedia storytelling in the music industry : The case of BTS." Thesis, Jönköping University, HLK, Medie- och kommunikationsvetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-54699.
Повний текст джерелаАнотація:
This case study research examines the impact of transmedia storytelling on the global reach of Korean-pop (K-pop) group BTS (Bangtan sonyeondan) and how narratives within the transmedia storyworld can motivate the audience to seek individual and social change. This study is inspired by the rise of BTS in the global music industry. The group came with a solid brand image, highlighting sincerity and authenticity that captivate audiences worldwide. BTS consistent messages—that intersect with sustainability issues—about the importance of loving oneself, equality, social justice, anxiety, and wellbeing are communicated through multiple platforms and travel across language and cultural barriers. To understand the context, this study uses the concepts of transmedia storytelling and audience engagement by Jenkins (2006, 2007, 2012, 2014), Gambarato (2019), Broesma (2019), and Askwith (2007), to name a few. The method used to conduct this research is the analytical and operational model of transmedia design by Gambarato et al. (2020). The findings are that transmedia storytelling —with spreadability, drillability, extractability, and immersion characteristics—is an effective communication strategy that significantly influences the global reach of the group. Further, the camaraderie between BTS and ARMY generates fan activism—an epitome of individual change due to the fondness to BTS, as the act of identification and the attitude of giving back to the intimacy that BTS members provide to the fandom.
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Brandel, Malin. "Representativitet av snödjup vid marktemperaturmätningar under snö för permafrostmodellering i området kring Tarfaladalen, norra Sverige." Thesis, Stockholms universitet, Institutionen för naturgeografi och kvartärgeologi (INK), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-95557.
Повний текст джерелаАнотація:
Snö och permafrost är två interagerande komponenter i Kryosfären. Studien undersöker snödjupets representativitet vid marktemperaturmätningar under snötäcket (BTS) för identifiering av permafrost i Tarfala, norra Sverige. Snödjupsmätningar har utfördes i två korsande 20 m transekter i nordsydlig (NS) samt östvästlig (ÖV) riktning utifrån en BTS-punkt. Totalt har 37 BTS (snödjup > 80 cm) med tillhörande snödjupsmätningar registrerats och analyserats. Snödjupet varierar både lokalt kring mätpunkten och regionalt i mättransekter men är ändå ett representativt snödjup för en punkt. Representativa BTS, sett ur ett snödjupsperspektiv, bör registreras på platser med måttlig snödjupsvariation som på platser med homogent markunderlag, vindskyddade områden, lä bakom ryggar och sluttningar vinkelräta mot den dominerande vindriktningen. BTS provplatser bör också ta hänsyn till de mest förekommande klasserna av parametrarna altitud, sluttning och slutningsriktning för att erhålla representativa BTS. Detta baserat på jämförelse mellan två strategier för insamling av BTS genom permafrostmodellering mellan två dataset. Ett BTS dataset från 2011 jämfört med BTS insamlade mars 2013.Snow and permafrost are two interacting components in the Cryosphere. This study is focusing on snow depth and its influence on bottom temperature of snow cover (BTS) in Tarfala, Northern Sweden. BTS indicate the absence or presence of permafrost if the snow depth > 80 cm. Snow depth measurements were carried out with a resolution of 1 m in two 20 m crossing transects in NS and EW direction around the BTS point. A total of 37 BTS with accompanying snow depths was measured and analyzed. Snow depths varied around the BTS but are representative for the measured 20 m transects. Locations with moderate snow depth variations make out representative probe sites from a snow depth perspective, such as homogenous ground cover, wind protected areas, in the lee behind ridges and slopes perpendicular towards the dominating wind direction. Also to find representative BTS probe site two strategies for collecting BTS have been evaluated through permafrost modeling. One dataset recorded in 2011 focused on covering a big variety of altitude, slope and aspects. The second dataset registered in March 2013 aimed to cover the most frequent classes of the mentioned parameters. The latter strategy is also the preferably method based on the comparison between the two models.
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Hosseini, Moghaddam Seyed Mazyar. "Designing battery thermal management systems (BTMS) for cylindrical Lithium-ion battery modules using CFD." Thesis, KTH, Energiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-244459.
Повний текст джерелаАнотація:
Renewable Energies have the capability to cut down the severe impacts of energy and environmental crisis. Integrating renewable energy generation into the global energy system calls for state of the art energy storage technologies. The lithium-ion battery is introduced in this paper as a solution with a promising role in the storage sector on the grounds of high mass and volumetric energy density. Afterward, the advantages of proper thermal management, including thermal runaway prevention, optimum performance, durability, and temperature uniformity are described. In particular, this review detailedly compares the most frequently adopted battery thermal management solutions (BTMS) in the storage industry including direct and indirect liquid, air, phase-change material, and heating. In this work, four battery thermal management solutions are selected and analyzed using Computational Fluid Dynamic (CFD) simulations for accurate thermal modeling. The outcome of the simulations is compared using parameters e.g. temperature distribution in battery cells, battery module, and power consumption. Liquid cooling utilizing the direct contact higher cooling performance to the conventional air cooling methods. However, there exist some challenges being adopted in the market. Each of the methods proves to be favorable for a particular application and can be further optimized.Integrering av förnybara energier i globala energisystem kräver enorma energilagrings teknologier. Litium jon batterier spelar en viktig roll inom denna sektor på grund av både hög vikt- och volymmässig energidensitet. Korrekt värmestyrning (Thermal management) är nödvändigt för litium jon batteriernas livslängd och operation. Dessa batterier fungerar bäst när de ligger inom intervallet 15–35 grader. dessutom har olika värmestyrsystem utvecklats för att säkerställa att batterierna arbetar optimalt i olika applikationer. I den här studien fem värmestyrningslösningar för batterier har väljas och analyseras med hjälp av beräkningsvätskedynamik (CFD) simulering. Resultaten av simuleringarna jämförs med olika parametrar som temperaturfördelning i battericeller, batterimoduler och strömförbrukning. Alla metoder visar sig vara användbara lämplig för viss tillämpning och kan vidare optimeras för detta ändamål.
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Odacre, Elisabeth. "L'enseignement des sciences économiques et gestion en BTS en Guadeloupe : entre prescrits nationaux et contexte socio-économique régional." Thesis, Antilles, 2018. http://www.theses.fr/2018ANTI0252/document.
Повний текст джерелаАнотація:
Même s’il existe une production de ressources pédagogiques s’appuyant sur des exemples pris en Guadeloupe ou dans son environnement, l’enseignement des sciences économiques et de gestion ne nous semble pas y avoir été considéré comme objet d’étude, alors qu’il interroge des composantes fondamentales du contexte de ce territoire comme la situation socio-économique et l’environnement réglementaire. Cette étude porte sur le fonctionnement de certains Brevets de Technicien Supérieur en Guadeloupe (BTS), diplôme professionnel français se préparant en deux ans après le baccalauréat, dont les programmes et critères d’évaluation sont nationaux. Les lauréats sont supposés pouvoir s’insérer immédiatement dans le monde professionnel, en particulier dans leur environnement géographique local et sont préparés à cette insertion par des stages en entreprises. Nous nous intéressons à la tension pouvant résulter d’une définition nationale du diplôme, le plus souvent en référence à des réalités de l’hexagone et le contexte local d’enseignement et d’insertion professionnelle, éloigné sur les plans sociaux-économiques et règlementaires. De manière plus précise, nous questionnons en premier lieu les conceptions de professeurs de ces BTS au regard de cette tension : existe-elle pour eux ? Comment la prenne-t-elle éventuellement en compte dans leur action pédagogique ? Ce questionnement a permis de préparer le second volet de notre étude, auprès d’étudiants de BTS. En effet, la question de l’insertion professionnelle ressort comme importante dans les propos des professeurs. Nous avons donc voulu savoir comment, au fil des stages – moments privilégiés de modification des représentations sociales des étudiants – leur projet professionnel s’affinait. Avant de réaliser ces enquêtes, nous avons dressé un paysage de la place du BTS en Guadeloupe et choisi de concentrer notre travail sur deux BTS, assistant de manager et tourisme, le premier possédant des prescrits faisant que peu référence à l’environnement du déroulement de la formation à l’opposé du second. Nous souhaitions ainsi pouvoir établir une comparaison basée sur ce que nous avons appelé l’ancrage contextuel d’une formation. La première enquête a été réalisée auprès de professeurs en économie-gestion des deux BTS retenus sous forme d’entretiens semi-directifs. Notre objectif était donc d’appréhender leurs conceptions et leurs pratiques déclarées quant à la contextualisation didactique. Les professeurs, faisant état d’effets de contexte occasionnés par la tension susmentionnée, déclarent en tenir compte dans leurs enseignements des sciences économiques et de gestion, en contextualisant leurs pratiques. Cependant, ces contextualisations restent limitées, les professeurs se sentant contraints par le cadre national du diplôme. Par exemple, en BTS tourisme, les décalages entre le contexte local et celui de l’hexagone peuvent provenir d’une mutation moins accomplie en Guadeloupe (au moment de l’enquête) vers la « tourismatique » (informatique appliquée au tourisme). En BTS assistant de manager, ces décalages peuvent résider dans les spécificités du contexte économique et fiscal comme par exemple, les régimes différents de TVA ou l’existence de l’octroi de mer en Guadeloupe : les professeurs hésitent à enseigner les règles en vigueur en Guadeloupe, de peur de pénaliser leurs étudiants lors des examens définis nationalement. Cette enquête a donc révélé l’existence de paradoxes, entre les visées professionnalisantes des BTS et les prescrits (référentiels, examens…) définis nationalement, et donc (partiellement) inadaptés aux divers contextes d’exercice des métiers. En ce qui concerne les étudiants, une enquête longitudinale par questionnaires a été menée auprès d’une cohorte de chacun des BTS retenus, sur la durée de la formationEven if there is a production of educational resources based on examples in Guadeloupe or its environment, the teaching of the economics sciences and management was not considered as an object of scientific study, though it questions fundamental components of the context of this territory like the socioeconomic situation and the regulatory environment. This study concerns the functioning of some French BTS (Brevet de Technicien Supérieur / Advanced Technician Certificate), a professional diploma prepared in two years after the “baccalaureat”, with national programs and evaluation criteria. The successful candidates are supposed to be immediately employable, especially in their local geographical environment, and are prepared for that by professional training sessions in companies. We are interested in a paradox which can be the result of the national definition of the diploma, in reference to the French mainland realities and the local contexts of teaching and of professional integration, far from the socio-economic and regulatory plans. Firstly, we wonder about the point of view of the teachers of those “BTS” about this paradox: does it exist for them? How is it taken into account in their educational action? These questions allowed us to prepare the second part of this study, among students of BTS. Indeed teachers think that the occupational integration is important. We wanted to know how, during and after professional training sessions– privileged moments for modification of the social representations of the student – their professional project became refined. Before doing these inquiries, we drew up a landscape of the place of the BTS in Guadeloupe and chose to focus our study on two BTS, namely assistant manager [deputy manger] and tourism. The first with programs with few references to the environment of the training, contrary to the second. We wanted to ensure a comparison on what we called the anchoring contextual of a training. In the first survey, we conducted semi-structured interview with Guadeloupean teachers of the two BTS mentioned previously. Our objective was to grasp their conceptions and their practices declared about the contextualization of didactics. The teachers, mentioned context effects, by the paradox mentioned previously and declare to take it account in their teachings of the economics sciences and management by contextualizating their practices. However, these contextualizations remain limited, the teachers feeling forced by the national frame of the diploma. For example, in BTS tourism, the gaps between the local context and the French mainland can result from a transformation less accomplished in Guadeloupe (at the time of the survey) towards the “tourismatique” (computing applied to tourism). In BTS assistant manager, these gaps may stay in the specificities of the economic and fiscal context as for example, the different sets of VAT or the existence of the duck dues in Guadeloupe: these adaptations remain limited by fear of disadvantaging the students for the national exam. This demonstrates paradoxes between the professionalizing aim of the BTS and its programs (exams), and thus (partially) unsuitable for the different contexts of the jobs background
26
Hällberg, Petter. "Permafrost Modelling and Climate Change Simulations in Northern Sweden." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-337794.
Повний текст джерелаАнотація:
Permafrost is an important component in Arctic environments and has been hypothesized to be diminishing due to global warming. A growing concern is that large quantities of stored organic carbon will be mobilized and released to the atmosphere as the potent greenhouse gas methane if the ground thaws. This could result in a massive positive feedback on the global climate change. To quantify this effect, the permafrost extent as well as carbon storages must be mapped. In this study, a Basal Temperature of Snow (BTS) survey is conducted in the Tarfala Valley in Northern Sweden and a model of the current permafrost extent in the region is produced. Additionally, the model explores how the permafrost extent will change under three climate change scenarios at +1°C, +2°C and +4°C. According to a statistical analysis, elevation is the only significant variable for permafrost occurrence in the Tarfala Valley. Currently, continuous permafrost (>0.8 probability) is present at elevations exceeding 1523 m a.s.l. and sporadic or patchy permafrost (<0.5 probability) dominates below 1108 m a.s.l. The permafrost in Northern Sweden is near the boundary of favorable conditions for permafrost, and the greatest decline in permafrost extent occurs during the initial warming. In the +1°C scenario, which will be reached in 20 years if current warming rate is sustained, 97.6% of the continuous permafrost in the Abisko and Tarfala area degrades. The areal extent of the zone with the lowest probability of permafrost occurrence increases from 59% to 90% in the same scenario. Under continued warming to +4°C compared to current ground temperatures, 98% of the study area will be covered by sporadic or patchy occurrences of permafrost.Permafrost är en viktig komponent i arktiska miljöer och befaras minska i utbredning på grund av den globala uppvärmningen. En farhåga är att stora mängder bundet organiskt kol ska mobiliseras och släppas ut till atmosfären som den potenta växthusgasen metan om marken värms. Detta skulle kunna innebära stor positiv återkoppling på de globalt stigande temperaturerna. För att kvantifiera den effekten är det viktigt att kartlägga permafrostens utbredning såväl som mängde bundet kol i permafrostmarker. I den här studien utförs en undersökning av bastemperaturen av snötäcket (BTS) i Tarfaladalen i norra Sverige och en modellering av permafrostens nuvarande utbredning i regionen. Vidare modelleras hur permafrostens utbredning kommer att påverkas i framtiden under tre olika klimatförändringsscenarior vid +1°C, +2°C och +4°C. Enligt en statistisk analys är altitud den enda signifikanta variabeln för permafrostförekomst i Tarfaladalen. Vid nuvarande marktemperaturer är kontinuerlig permafrost (>0.8 probabilitet) utbredd på höjder över 1523 m ö.h. och sporadisk permafrost (0.5 - 0 probabilitet) dominerar under 1108. Permafrosten i norra Sverige är nära gränsen för dess gynnsamma förhållanden och den huvudsakliga förlusten av permafrost sker redan vid en blygsam markuppvärmning. I scenariot +1°C, som inträffar redan om 20 år om nuvarande uppvärmningstakt fortsätter, degraderas 97.6% av den kontinuerliga permafrosten i Abisko och Tarfalaområdet. Utbredningen av sporadisk permafrost, det vill säga zonen med lägst sannolikhet för permafrostförekomst, ökar i det scenariot från 59% till 90%. Vid fortsatt uppvärmning till +4°C jämfört med nuvarande marktemperaturer så kommer 98% av det studerade området endast innehålla sporadiska förekomster av permafrost.
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Orange, Sophie. "L'autre supérieur : aspirations et sens des limites des étudiants de BTS." Poitiers, 2011. http://www.theses.fr/2011POIT5016.
Повний текст джерелаАнотація:
L'objet de cette thèse est d'interroger les différents cadres sociaux qui enserrent l'expérience étudiante en sections de technicien supérieur (STS). Ces formations constituent les voies d'accès privilégiés voire exclusives à la poursuite d'études pour une large fraction des bacheliers technologiques et professionnels, contribuant ainsi fortement à l'élévation de la demande d'éducation en milieu populaire. Le suivi d'une cohorte d'étudiants depuis leur entrée en STS jusqu'à leur sortie permet de mettre en évidence les effets de l'institution sur leurs aspirations scolaires et professionnelles. Il apparaît alors que le passage en STS participe d'une augmentation des ambitions scolaires chez des publics initialement peu enclins aux études longues, par le caractère fortement intégrateur des classes et par l'élévation des étudiants au rang de petite élite locale, notamment dans certains établissements ruraux. En ce sens, ces formations assument pleinement un rôle de promotion sociale. Cependant, la spécificité des curricula et la diversité interne des configurations pédagogiques qui caractérisent les STS contraignent dans le même temps les étudiants à une certaine modestie dans leurs exigences professionnelles. En outre la situation des STS à la marge du supérieur et leur position hors du LMD fragilisent les passerelles vers les cycles long. Au final, ces formations ne parviennent pas à assurer complètement les vocations scolaires qu'elles suscitent pourtantThe aim of this thesis is to analize the different social frameworks which are the background of the studying experience in french higher technical sections (Sections de Technicien Supérieur - STS). These vocationnal trainings are the preferred or even the exclusive pathways to the higher education levels, chosen by many vocational and technical "baccalauréat" graduates, thus contributing to the growth of a demand for education in low-income families. The monitoring of a group of students from their entry in STS until their graduation highlight the effects of the institution on school and job ambitions. It appears that the high integration potentential of these training courses and eventually the consecration of the students as a local elite in rural secondary schools allow increasing aspirations of weaker students. Thus, STS play a role of social promotion. However, curricula specificities and internal diversities of pedagogical configurations lead students to moderate their professionnal expectations. Furthermore, the isolation of STS in the french higher education system, a consequence of the LMD reform, has reduced the possibilities for the students to move towards long cycles. Consequently, these training courses are not able to completely guarantee the academic vocations they gave rise to
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Blomdahl, Klara. "Förändringar i BTS-temperatur i Storglaciärens ablationsområde mellan 2001 till 2011." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-201721.
Повний текст джерелаАнотація:
Klimatologiska förändringar har en direkt påverkan på glaciologiska system genom att förändra glaciärers termiska struktur. Subarktiska Skandinavien har upplevt en klimatologisk uppvärmning sedan 1980-talet och Tarfaladalen har under samma period uppvisat en ökad vintertemperatur med 1°C. Ökade vintertemperaturer medför förändringar i glaciärers temperaturfördelning, då högre temperaturer ger en längre smältsäsong. Storglaciären i Kebnekaisemassivet i svenska Lappland har en polytermal temperaturfördelning med ett kallt ytskikt i ablationsområdet. Det kalla ytskiktet har förtunnats med 22% sedan slutet av 1980-talet och då ingen ökad sommarablation har kunnat konstateras kan den ökade vintertemperaturen vara en indikator för att isyttemperaturen är styrande för det kalla ytskiktets bevarande. Syftet med mitt projekt är att påvisa förändringar i isyttemperaturen i Storglaciärens ablationsområde mellan åren 2001 och 2011. Förändringarna relateras till mönstret i det kalla ytskiktets tjocklek och dess förändring över tid. I månadsskiftet mars-april 2011, innan vårsmältningen, mättes temperaturen vid isytan vid 46 mätpunkter distribuerade över Storglaciärens ablationsområde. Temperaturen under snötäcket, bottom temperature of snow cover (BTS) är stabil genom vintern under förutsättningen att snödjupet är tillräckligt stort (>0.8 meter) för att isolera isytan från korttidsvariationer i lufttemperaturen. Då den manuella temperaturmätningen enbart ger punktdata, gjordes sedan en interpolering för hela ablationsområdet. De interpolerade BTS-temperaturerna från 2011 visar företrädesvis varmare temperaturer i ablationsområdets nordligaste delar. De uppmätta BTS-temperaturerna från 2011 visar likheter med fördelningen av det kalla ytskiktets mäktighet över glaciären från 2009. Områden med högre BTS-temperaturer sammanfaller med områden med ett tunnare kallt ytskikt, medan ett mäktigare kallt ytskikt är associerat med lägre BTS-temperaturer. Områden med de högsta BTS-temperaturerna 2011 korrelerar även med de områden där uttunningen av det kalla ytskiktet har varit som störst mellan 2001 till 2009. Mönstret av uttunningen reflekteras i BTS-temperaturerna trots att det är andra förhållanden och BTS-temperaturen bör därför kunna användas som en indikator för förändringar i CTS position och det kalla ytskiktets tjocklek.Climatological changes have a direct impact on glacial systems by altering the thermal structure of glaciers. Sub-Arctic Scandinavia has experienced a climatic warming since the 1980s and the Tarfala valley has showed an increase in winter temperature by 1°C during the same period. Increased winter temperatures result in changes in the glacial temperature distribution, since higher temperatures contribute to a longer melt season. Storglaciären in the Kebnekaise massif in Swedish Lapland has a polythermal temperature distribution with a cold surface layer in the ablation area. The cold surface layer has experienced a thinning by 22% since the late 1980s and, since no significantly increased summer ablation has been noted, the increased winter temperature may be an indicator that the ice surface temperature is a controlling factor for the preservation of the cold surface layer. The aim of my project is to detect changes in the ice surface temperature in the ablation area of Storglaciären between 2001 and 2011. The changes are related to the pattern of the cold surface layer thickness and its change over time. In March-April 2011, before the spring melt, the temperature at the ice surface was measured at 46 locations distributed in the ablation area of Storglaciären. The bottom temperature of snow cover (BTS) is stable through the winter under the premise that the snow cover is sufficiently thick (>0.8 meters) to insulate the ice surface from short-term variations in air temperature. Since the manual temperature measurement only provides point data, an interpolation was made for the entire ablation area. The interpolated BTS-temperatures from 2011 show relatively warmer temperatures in the northernmost parts of the ablation area. The measured BTS-temperatures from 2011 show similarities with the distribution of the cold surface layer thickness of the glacier from 2009. Areas with higher BTS-temperatures coincide with areas with a thinner cold surface layer, whilst a thicker cold surface layer is associated with lower BTS-temperatures. Areas with the highest BTS-temperatures in 2011 also correlate with the areas where the thinning of the cold surface layer was greatest between 2001 until 2009. The pattern of the thinning is reflected in the BTS-temperatures, despite that there are other conditions and the BTS-temperature might therefor be a possible indicator for changes in the CTS position and the cold surface layer thickness.
29
Marklund, Per. "Alpin permafrost i Kebnekaisefjällen : Modellering med logistisk regression och BTS-data." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-174485.
Повний текст джерелаАнотація:
Denna studie är ett försök att modellera den alpina permafrostens utbredning inom Kebnekaisemassivet i norra Lappland. En karta som visar sannolikheten för permafrostens utbredning har skapats med hjälp av data från Bottom Temperature of Snow cover (BTS) - mätningar samt statistisk modellering genom logistisk regression. Fältstudien genomfördes under mars till april 2011 med totalt 56 BTS-punkter från 1073 till 1805 m.ö.h. Permafrostförekomsten bestämdes vara en funktion av höjden. För att utreda detta användes stepwise selection som är en metod för att identifiera statistiskt signifikanta variabler gentemot en beroende variabel. De andra parametrarna som testades var topografins sluttningsgradient, riktningen av den maximala lutningen och den potentiella solinstrålningen. Dessa parametrars inverkan på permafrostförekomsten ansågs vara försumbara, och de bortsågs därför från i modelleringen. Modelleringen indikerar att permafrost med sannolikhet större än 0,8 existerar över 1190 m.ö.h, och med sannolikhet mellan 0,8 till 0,5 finns mellan 1190 till 1144 m.ö.h. Eftersom fältstudien är begränsad till Tarfaladalen så är modelleringens förutsägelse för förekomsten av permafrost i andra delar av fjällmassivet mera osäkert.This study presents an attempt to model the limits of mountain permafrost distribution within the Kebnekaise massif in northern Sweden. A map showing the probabilities for the mountain permafrost distribution has been created using statistical modelling through logistic regression of Bottom Temperature of Snow cover (BTS) measurements. The survey was conducted in March to April 2011 with a total of 56 BTS-point measurements stretching from 1073 to 1805 m.a.s.l. Permafrost occurrence was determined to be a function of altitude. This was determined by a stepwise selection analysis, a method used for identifying parameters with a statistical significance against a dependent variable. The other parameters that were tested for significance were the slope and aspect of the topography, and the potential incoming solar radiation. Although these might have an influence on the permafrost occurrence, they were considered to be of less importance and were thus neglected in the modelling. The model indicates permafrost with greater than 0,8 probability at and above 1190 m.a.s.l, and with probability from 0,8 to 0,5 between 1190 to 1144 m.a.s.l. Since the survey was carried in the Tarfala valley, the result of the modelling is more uncertain in the parts of the area which lie outside of this valley.
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Fernandez, Maldonado Tincopa Silvana. "Bangtan Universe: Análisis de la estrategia transmedia del grupo Kpop BTS." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2021. http://hdl.handle.net/10757/657417.
Повний текст джерелаАнотація:
En el presente trabajo de investigación se analizará la capacidad que tiene la música para expandir sus relatos a diferentes pantallas con la finalidad de que los músicos y artistas que se encuentran en el medio, como también los que están ingresando, se interesen por nuevas alternativas en cuanto a generar contenido para su público.
El objeto de estudio para esta investigación es el exitoso grupo de Kpop BTS y se analizará la estrategia transmedia de la banda abordando los conceptos de narrativa transmedia, intertextualidad, prosumidores y todo lo que implica ser parte de la cultura fan. En cuanto a la metodología del proyecto, se realizará un análisis de contenido tanto de la banda como del material generado por los fans; por último, se analizará la experiencia de usuario en el relato de las piezas musicales de BTS mediante entrevistas semiestructuradas.In this research work, the capacity of music to expand its stories to different screens will be analyzed in order that the musicians and artists who are in the middle, as well as those who are entering, are interested in new alternatives of generating content for their audience. The object of study for this research is the successful kpop group BTS and the transmedia strategy of the band will be analyzed, addressing the concepts of transmedia narrative, intertextuality, prosumers and everything that implies being part of the fan culture. Regarding the methodology of the project, a content analysis of both the band and the material generated by the fans will be carried out; finally, the user experience in the story of BTS's musical pieces will be analyzed through semi-structured interviews.
Trabajo de investigación
31
Xiang, Haiou. "BLUETOOTH-BASE WORM MODELING AND SIMULATION." Master's thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2669.
Повний текст джерелаАнотація:
Bluetooth is one of the most popular technologies in the world in the new century. Meanwhile it attracts attackers to develop new worm and malicious code attacking Bluetooth wireless network. So far the growth of mobile malicious code is very fast and they have become a great potential threat to our society. In this thesis, we study Bluetooth worm in Mobile Wireless Network. Firstly we investigate the Bluetooth technology and several previously appeared Bluetooth worms, e.g. "Caribe","Comwar", and we find the infection cycle of a Bluetooth worm. Next, we develop a new simulator, Bluetooth Worm simulator (BTWS), which simulates Bluetooth worm' behaviors in Mobile wireless networks. Through analyzing the result, we find i) In ideal environment the mobility of Bluetooth device can improve the worm's propagation speed, but combining mobility and inquiry time issue would cause a Bluetooth worm to slow down its propagation under certain situation. ii) The number of initially infected Bluetooth devices mostly affects the beginning propagation speed of a worm, and energy issue can be ignored because the new technology can let Bluetooth device keeping work for a long time. iii) Co-channel interference and setting up monitoring system in public place can improve the security of Bluetooth wireless network.M.S.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Computer Science MS
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Benetti, Caroline Nocêra. "ESTUDO DA DEGRADAÇÃO DE ÁGUAS CONTAMINADAS ARTIFICIALMENTE POR GASOLINA COMUM VIA SISTEMA FENTON E FOTO-FENTON." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2017. http://tede2.uepg.br/jspui/handle/prefix/2051.
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Previous issue date: 2017-03-30Oil spills and their derivatives are the main source of water contamination, among them the aromatic hydrocarbons benzene, toluene and xylene (BTX) present in gasoline are some of the most toxic compounds that need to be degraded. Therefore, there is a need for a study of the recently applied advanced processes for remediation considering the characteristics of gasoline marketed in Brazil. In addition, toxicity studies can contribute to assessing the actual quality of contaminated water after remediation, that is assessing impacts to the environment. In this context, the objective of this work was to study the Fenton and photo-Fenton degradation processes for the remediation of water contaminated with benzene, toluene and xylenes and toxicity. The methodology used to determine the BTX was via gas chromatography being the form of extraction through the headspace. A gasoline spill was simulated in water to obtain a soluble fraction where it was possible to verify by Total Organic Carbon the concentration present in the medium. Using the factorial design of experiments, it was possible to verify the best condition of iron and hydrogen peroxide to be used in the Fenton and photo-Fenton process, that is, the concentration where there is greater removal of BTX. The chosen values being 5 mg L-1 of iron and 15 mg L-1 of hydrogen peroxide. The monitoring of phenolic compounds showed that in the first few minutes of reaction phenolic species formation and subsequent decrease, but remaining still significant (approximately 20%) at the end of 120 minutes. Thus, these results have shown that for effective mineralization larger reaction times are still needed. In the determination of the residual peroxide and ferrous and ferric ions it was based by the calorimetric method showing that at the end of the Fenton processes peroxide was not as consumed as in the photo-Fenton process where more hydroxyl radicals (HO) are generated. Toxicity tests performed with the Sinapis alba and Daphnia magna bioindicators for toxicity assessment showed that the by-products formed during the degradation systems caused toxicity to the test organisms used. Thus, it is evident that in addition to the physico-chemical parameters normally evaluated, there is also a need for toxicity studies to evaluate the true impact on the environment of water submitted to this type of remediation.
Os derramamentos de petróleo e seus derivados são a principal fonte de contaminação das águas, dentre eles os hidrocarbonetos aromáticos benzeno, tolueno e xileno (BTX) presentes na gasolina são alguns dos compostos mais tóxicos e que tem a necessidade de serem degradados. Portanto, há a necessidade de um estudo dos processos avançados recentemente aplicados para a remediação considerando as características da gasolina comercializada no Brasil. Além disso, estudos de toxicidade podem contribuir para avaliar a real qualidade da água contaminada após remediação, ou seja, avaliar impactos ao meio ambiente. Dentro deste contexto, o objetivo deste trabalho foi estudar os processos de degradação via sistema Fenton e foto-Fenton para a remediação de águas contaminadas com benzeno, tolueno e xilenos e a toxicidade. A metodologia utilizada para determinação dos BTX foi via cromatografia gasosa sendo a forma de extração através do headspace. Fez-se uma simulação de um derramamento de gasolina em água para obter uma fração solúvel onde foi possível verificar por Carbono Orgânico Total a concentração presente no meio. Utilizando o planejamento fatorial de experimentos foi possível verificar qual é a melhor condição de ferro e peróxido de hidrogênio a ser utilizada no processo Fenton e foto-Fenton, ou seja, a concentração onde há maior remoção de BTX. Sendo os valores escolhidos de 5 mg L-1 de ferro e 15 mg L-1 de peróxido de hidrogênio. O monitoramento de compostos fenólicos mostrou que nos primeiros minutos de reação há formação de espécies fenólicas e posterior diminuição, mas permanecendo ainda significativa (aproximadamente 20%) no final de 120 minutos. Assim, estes resultados demonstraram que para efetiva mineralização tempos maiores de reação ainda são necessários. Na determinação do peróxido residual e de íons ferrosos e férricos foi baseado através do método calorimétrico mostrando que ao final dos processos Fenton o peróxido não foi tão consumido quanto no processo foto-Fenton onde são gerados mais radicais hidroxila (HO.). Ensaios de toxicidade realizados com os bioindicadores Sinapis alba e Daphnia magna para avaliação da toxicidade mostraram que os subprodutos formados durante os sistemas de degradação provocaram toxicidade aos organismos testes utilizados. Assim, ficando evidente que além dos parâmetros físico-químicos normalmente avaliados, há também a necessidade de estudos de toxicidade para avaliar o verdadeiro impacto ao meio ambiente de águas submetidas a este tipo de remediação.
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Raschke, Marcus, and Victor Peterson. "Termisk energilagring i borrhål : En studie av borrhålets temperaturinverkan på värmepumpens värmefaktor." Thesis, KTH, Byggteknik och design, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-147305.
Повний текст джерелаАнотація:
Sverige har en hög andel installerade bergvärmepumpar, som är en typ av vätska-vatten värmepump. Ett problem som finns för befintliga bergvärmesystem är att berget med tiden kyls ned då returslangen till borrhålet konstant levererar kyla till berget. Till följd av detta mister systemet en betydande del av sin verkningsgrad samtidigt som det i extrema fall kan leda till permanent isbildning i borrhålet. Ett sätt att motverka detta problem är att tillämpa termisk energilagring i bergvärmesystemets borrhål. Den internationella benämningen för denna teknik är ”Borehole Thermal Energy Storage, BTES”. Rapporten har behandlat en friliggande enplansvilla med ett befintligt bergvärmesystem som tillämpar termisk energilagring i bergvärmesystemets borrhål med solvärme. Två beräkningsfall har gjorts och resultatet från simuleringarna i en upprättad beräkningsmodell visar att en temperaturhöjning i borrhålet inte alltid innebär en årlig energibesparing. Vid varje grads temperaturhöjning sker en ökning av värmepumpens COP med ca 1,85 % enligt ett linjärt samband för höga temperaturdifferenser över värmepumpen. Detta motsvarar en kostnadsbesparing på 1,02 %/°C. Detta gäller för normala förhållanden med en framledningstemperatur för tappvarmvatten och rumsvärmare på 55 ⁰C. Med en högre energiförbrukning finns alltså större besparingar att göra. Vid mycket låga temperaturdifferenser mellan förångare och kondensor sker dock större procentuella förändringar, vilket medför att lågtemperatursystem kan bidra till en större energibesparing. I normalfallet är dessa system svåra att räkna hem för småhus. För en god lönsamhet krävs en optimerad systemlösning och effektiv styrning av cirkulationspumpar och andra samspelande komponenter med en PLC. I framtiden kommer dock sannolikt värmepumparnas mekaniska verkningsgrad att öka med bättre teknik och även energipriset som följd av politiska beslut, tillgång etc. Detta innebär att varje besparad kilowattimme kommer att bli mer värd.Sweden has a high proportion of installed geothermal heat pumps, which are a type of liquid -water heat pump. One problem that exists for existing geothermal heating systems is that the rock in time cool down when the return hose to the borehole constantly supply cooling to the rock. As a result of this the system loses a significant portion of their efficiency while in extreme cases has led to the permanent ice in the borehole. One way to counter this problem is to apply thermal energy storage in the geothermal heating systems borehole. The international term for this technique is "Borehole Thermal Energy Storage, BTES". This report has analyzed a detached single storey house with an existing geothermal heating system utilizing thermal energy storage in the geothermal heating systems borehole with solar heating. Two calculation cases has been made and the results of the simulations in an established computational model shows that an increase in temperature in the borehole does not always result in an annual energy savings. Each degree of increased temperature is an increase in the heat pumps COP of 1.85 %, according to a linear relationship for high temperature differences across the heat pump. This results in a cost saving of 1.02 %/°C. This applies to normal conditions with a radiator temperature at 55 ⁰ C. With higher energy consumption can greater savings be made. At very low temperature differences between the evaporator and condenser is however larger percentage changes made, which means that low temperature systems can lead to greater energy savings. Typically, these systems are difficult to recoup for small detached houses. For a good profitability requires an optimized system solution and efficient control of circulation pumps and other interacting components with a PLC. In the future the heat pump mechanical efficiency will probably increase with better technology and even energy prices as a result of political decisions, access, etc. This means that each spared kilowatt hour will be worth more.
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Strohdeicher, Carsten. "Risiken des automatisierten Zahlungsverkehrs beim Einsatz von POS (ECS), Geldautomaten und BTX /." Frankfurt am Main ; Bern ; New York ; Paris : Lang, 1991. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=002711734&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Stofela, Sara Karoline Figueiredo 1989. "Remoção de compostos BTX em argila organofílica por adsorção em fase líquida." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266117.
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Orientador: Melissa Gurgel Adeodato VieiraDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: Resíduos contaminados com compostos orgânicos, sendo grande parte formados por hidrocarbonetos aromáticos, como o benzeno, tolueno e xileno, vem sendo gerados em grandes quantidades nas indústrias e em derramamentos de postos de estocagem de combustíveis. Sendo assim, surge espaço para novas pesquisas de tratamento desses efluentes, como a adsorção em argilas organofílicas. Portanto, o objetivo deste trabalho é avaliar o potencial da argila organofílica Spectrogel na adsorção dos compostos BTX. Para este estudo foram realizados teste de hidratação e expansão em meio orgânico, estudo do efeito do pH, avaliação do potencial de remoção e estudo cinético, por meio de ensaios cinéticos de adsorção monocomposto, bicompostos e tricompostos, estudo de equilíbrio, atráves de ensaios de equilíbrio monocomposto, bicompostos e tricompostos, nas temperaturas de 15, 25 e 35 oC, estudo termodinâmico, caracterização do material adsorvente antes e após os ensaios de adsorção, estudo de regeneração do adsorvente, e análise estatística do processo de adsorção. A argila apresentou uma eficiência de remoção de 95%, 89% e 96% para o benzeno, tolueno e xileno, respectivamente e mostrou que o processo é rápido com no máximo 120 min para atingir o equilíbrio. No estudo cinético, tanto o modelo pseudoprimeira-ordem, quanto o pseudossegunda ordem apresentaram boas correlações. O modelo de difusão intrapartícula e modelo de Boyd indicaram que a adsorção é controlada tanto pela difusão intrapartícula, como pela difusão externa. O estudo de equilíbrio indicou que o xileno é o contaminante com maior afinidade pelo meios adsorvente. Entre os modelos de isotermas utilizados nos ajustes dos dados experimentais, o modelo de Dubinin-Radushkevitch foi o que apresentou melhor correlação para todas as isotermas monocomposto. Para as isotermas bicompostos, o modelo de Freundlich foi o que melhor se ajustou. Os parâmetros termodinâmicos mostraram que o processo de adsorção de BTX em argila Spectrogel é espontâneo e endotérmico. A caracterização do adsorvente após a adsorção dos BTX mostrou que o mesmo é pouco poroso e possui a superfície heterogênea, evidenciando a presença dos compostos BTX e algumas mudanças estruturais no material adsorvente. Por fim, os ensaios de regeneração indicaram a regeneração do adsorvente por meio do eluente etanol
Abstract: Contaminated waste with organic compounds, being largely composed of aromatic hydrocarbons such as benzene, toluene and xylene, has being generated in large quantities in industries and spills fuel storage stations. Thus, it arises space for further research about treatment of these effluents, such as adsorption on organoclay. Therefore, the aim of this study is to evaluate the adsorption of BTX compounds into organoclay Spectrogel. For this study tests of hydration and expansion in organic media and tests of the effect of pH were conducted. Equilibrium study was also performed by tests of mono-component, bi-component and multicomponent solutions at temperatures of 15, 25 and 35 oC. The adsorbent was characterized before and after the adsorption experiments. Finally, the regeneration of the adsorbent through eluents and a statistical study of the adsorption process were also performed. The evaluation of the potential removal provided a removal efficiency of 95%, 89% and 96% for benzene, toluene and xylene, respectively and showed that the process is fast taking a maximum of 120 min to reach equilibrium. In the kinetic study, both the pseudo first order model, as well as pseudo second order model showed a good correlation. The intraparticle diffusion model and Boyd model indicated that adsorption is controlled by both intraparticle diffusion and external diffusion. The equilibrium study indicated that xylene is the most competitive contaminant by active adsorption site. Among the isotherm models used, only the Dubinin-Radushkevitch showed a good correlation for all mono-component isotherms. For bi-component isotherms, the Freundlich model showed the best fit. The thermodynamic parameters indicated that the adsorption process of BTX into clay is spontaneous and endothermic. The characterization of the study showed that the this adsorbent is porous and presents a heterogeneous surface after adsorption and the presence of BTX compounds and structural changes were observed in the adsorbent material after process. The dessorption tests indicated a possible regeneration of the adsorbent using ethanol as eluent.z
Mestrado
Desenvolvimento de Processos Químicos
Mestra em Engenharia Química
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Nascimento, Meggie Karoline Silva. "Avaliação da toxicidade dos hidrocarbonetos monoaromáticos BTX no microcrustáceo marinho Mysidopsis juniae." Universidade Federal de Sergipe, 2017. https://ri.ufs.br/handle/riufs/4480.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESThe volatile organic compounds benzene, toluene and xylenes (BTX) are among the most produced chemicals worldwide and can be found in different environmental compartments. Contamination of aquatic environments by these substances may result in to adverse toxic effects on organisms of different biological organizations. The present study aimed to evaluate the toxicity of BTX isolated and in binary mixtures using the acute toxicity test (96h) with the microcrustacean Mysidopsis juniae. To achieve that, organisms were exposed to BTX concentrations in order to identify the effects on survival, as well as to study the modes of action of the substances in mixture with the application of the theoretical models of Addition Concentration (AC) and Independent Action (AI). In the experiments with the isolated compounds it was possible to notice that xylene was the most toxic compound (LC50 16,10 ±2,4mg.L-1) followed by toluene (LC50 38 ± 5,3mg.L-1) and benzene (LC50 78,03 ±2,9mg.L-1) respectively. When in binary mixture deviations of the reference models for CA were observed in all experiments performed (dose ratio and antagonism). In the exposure of xylene and benzene the deviation that fit the results was the antagonism, where as the mixture of xylene and toluene was better explained by the deviation dose ratio where the toxicity was caused mainly by xylene. In the experiment combining toluene and benzene, the dose ratio pattern was observed as well, and the benzene was the main responsible for the toxicity. We concluded that BTX were toxic to mysids, both isolated and in binary mixtures, evidencing the importance of studies in this subject that can serve as support for evaluations and monitoring of the marine environments, considering the imminent risks of contamination of this environment and the wide scale of use of these compounds.
Os compostos orgânicos voláteis benzeno, tolueno e os xilenos (BTX) estão entre os produtos químicos mais produzidos mundialmente e podem ser encontrados em diferentes compartimentos ambientais. A contaminação de ambientes aquáticos por essas substâncias pode acarretar em efeitos tóxicos adversos em organismos de diferentes organizações biológicas. Diante disso, o presente estudo teve como objetivo avaliar a toxicidade dos BTX isolados e em misturas binárias por meio do teste de toxicidade aguda (96h) com o microcrustáceo Mysidopsis juniae. Para isso, os organismos foram expostos às concentrações de BTX a fim de identificar os efeitos na sobrevivência, assim como estudar os modos de ação das substâncias em mistura com a aplicação dos modelos teóricos de concentração de adição (CA) e ação independente (IA). Nos experimentos com os compostos isolados foi possível perceber que o xileno foi o mais tóxico (CL50 16,10±2,4mg.L-1) seguido por tolueno (CL50 38±5,3mg.L-1) e benzeno (CL50 78,03±2,9mg.L-1). Quando em mistura binária foram observados desvios dos modelos de referência para CA em todos os experimentos realizados (razão das doses e antagonismo). Na exposição do xileno e benzeno o desvio que se enquadrou aos resultados foi o antagonismo, já a mistura de xileno e tolueno foi melhor explicada pelo desvio razão das doses onde a toxicidade foi causada principalmente pelo xileno, no experimento com o tolueno e benzeno também foi observado um padrão de razão das doses, sendo que nesse caso o benzeno foi o maior responsável pela toxicidade. Logo, os hidrocarbonetos analisados foram tóxicos para o misidáceo, tanto isolados como em misturas binárias, evidenciando a importância de estudos nessa temática que possam servir de suporte para avaliações e monitoramento dos ambientes marinhos, visto os riscos iminentes de contaminação deste meio e a ampla escala de utilização desses compostos.
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Portilla, Ovejero Mª Teresa. "Zeolitas para la obtención y redistribución de aromáticos en la fracción BTX." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/59471.
Повний текст джерелаАнотація:
[EN] This thesis focusses on reactive processes catalysed by zeolites to obtain and convert BTX aromatics. These compounds, together with light olefins, are the pillars of the petrochemical and organic chemical industry, as they are the raw materials to produce basic intermediates, such as polyester monomers, polyamides, engineering plastics and intermediate products for the manufacture of detergents, pharmaceuticals, fertilizers, and explosives.
Currently, the aromatics and light olefins are obtained mainly from petroleum refining, natural gas or coal. Along the last decades, natural gas conversion into higher value chemicals has gained importance, such as olefins and aromatics. The main reasons are its high hydrogen to carbon (H/C), its composition, which is independent of the source, and its availability, as world reserves are larger than those of oil, especially if shale gas is considered. Therefore, the methane aromatization reaction (MDA) is studied as a route for obtaining aromatics. The most widely used catalyst for this reaction is Mo/H-ZSM-5. Thus, the effect of various parameters on the catalyst activity has been studied, such as the physico-chemical properties of the parent sample and the metal component incorporation procedure, in order to find the optimum catalyst Mo/ZSM-5. Moreover, this study has allowed correlating successfully amount and nature of the two active centers involved in this reaction with methane conversion and product distribution. On the other hand, one of the mayor drawbacks of this reaction is the strong deactivation of the catalyst; therefore, a study of the regeneration possibilities has been carried out and has allowed the design of an effective protocol to prolong the catalyst life and with the aim of expanding its industrial applications. Furthermore, other medium pore and multipore zeolitic structures have been studied as alternative to ZSM-5 zeolite, and their catalytic behavior has been successfully correlated with their topologies.
Regarding the transformation and redistribution of the BTX aromatics, alkylation, disproportionation and isomerization reactions have been studied, which employ acid zeolites as catalyst to obtain alkylaromatics with high interest for the petrochemical industry, such as xylenes, ethylbenzene, cumene, ethyltoluene and cymene. The main zeolites used in these processes at commercial scale are ZSM-5, MCM-22, Beta and MOR. Therefore, new zeolitic materials have been studied considering the molecular dimension of reactants, products and reaction intermediates, as well as the dimensions of the zeolite's pore topologies. Multipore zeolites have also been included in this study, due to the potential "molecular traffic control" type of selectivity that can be improved by these structures presenting interconnected channel apertures of different size. The best performing zeolitic structures for these processes are ITQ-13, ITQ-22, ITQ-39 and ITQ-47, which due to their good catalytic behavior, could be considered as an attractive alternative to be used as catalysts on commercial scale.[ES] La presente tesis doctoral se centra en procesos reactivos catalizados mediante zeolitas para la obtención y transformación de aromáticos (fracción BTX). Estos compuestos son, junto con las olefinas ligeras, los pilares sobre los que se basa la industria petroquímica y de química orgánica en general, pues son la materia prima para muchos productos, tales como monómeros de poliésteres, poliamidas, plásticos de ingeniería, y productos intermedios para la fabricación de detergentes, fármacos, fertilizantes, y explosivos. Actualmente los aromáticos y las olefinas se obtienen principalmente del refino del petróleo, del gas natural o del carbón. En las últimas décadas ha ganado importancia la transformación del gas natural a productos químicos de mayor valor añadido, tales como olefinas y aromáticos, en parte debido a su elevada relación hidrógeno-carbono (H/C), a que su composición es independiente de la fuente de donde provenga, y a que las reservas mundiales de gas natural son superiores a las de petróleo, especialmente si se tiene en cuenta el gas pizarra. En la presente tesis, se ha estudiado la reacción de aromatización de metano (MDA) como una alternativa para la obtención de aromáticos. El catalizador más empleado para esta reacción es Mo/H-ZSM-5. Así, se ha estudiado la influencia de diversos parámetros en la actividad catalítica del mismo (propiedades físico-químicas de la zeolita de partida y método de incorporación del componente metálico) con el objetivo de buscar el catalizador Mo/ZSM-5 óptimo. Este estudio ha permitido correlacionar los dos tipos de centros activos involucrados en esta reacción con la conversión de metano y la formación de productos. Uno de los grandes inconvenientes que presenta esta reacción es la fuerte desactivación que sufre el catalizador, por lo que se ha realizado un estudio de las posibilidades de regeneración del mismo, lo que ha permitido diseñar un protocolo de trabajo útil para alargar la vida del catalizador y ampliar sus posibilidades de aplicación a nivel industrial. Además, se ha estudiado el empleo de otros materiales zeolíticos con estructuras de poro medio y multiporo como posibles alternativas a la ZSM-5, y se ha correlacionado su comportamiento catalítico con las distintas topologías. Dentro del marco de las reacciones de transformación y redistribución de aromáticos (BTX), se han estudiado reacciones para la obtención de alquilaromáticos de gran interés para la industria petroquímica, tales como xilenos, etilbenceno, cumeno, etiltolueno y cimeno, mediante reacciones de alquilación, desproporcionación e isomerización, donde se implican zeolitas como catalizadores ácidos. Las zeolitas principalmente empleadas en estos procesos a escala industrial son ZSM-5, MCM-22, Beta y MOR. Por lo tanto, se han estudiados nuevos materiales zeolíticos como catalizadores alternativos en estos procesos, teniendo en cuenta las dimensiones moleculares de los reactantes, productos e intermedios de reacción requeridos, conjuntamente con las dimensiones topológicas de las estructuras zeolíticas. También se han incluido en este estudio zeolitas multiporo, muy interesantes por permitir controlar el tráfico molecular a través de las diferentes aperturas de sus canales. En estos procesos reactivos, han destacado las zeolitas ITQ-13, ITQ-22, ITQ-39 e ITQ-47 por presentar un buen comportamiento catalítico, planteándose como posibles alternativas a los catalizadores empleados a escala industrial.
[CAT] La present tesi doctoral es centra en processos reactius catalitzats mitjançant zeolites per a l'obtenció i transformació d'aromàtics (fracció BTX). Estos compostos són, juntament amb les olefines lleugeres, els pilars sobre els que es basa la indústria petroquímica i de química orgànica en general, doncs són la matèria prima per a molts productes, com són monòmers de polièsters, poliamides, plàstics d'enginyeria, i productes intermedis per a la fabricació de detergents, fàrmacs, fertilitzants, i explosius. Actualment els aromàtics i les olefines s'obtenen principalment del refinatge del petroli, del gas natural o del carbó. En les últimes dècades ha guanyat importància la transformació del gas natural a productes químics de major valor afegit, com són les olefines i els aromàtics. Açò es degut a la seua elevada relació hidrogen-carbó (H/C), a que la seua composició és independent de la font d'on provinga, i a que les reserves mundials de gas natural són superiors a les del petroli, especialment si es té en compte el gas pissarra. En la present tesi, se ha estudiat la reacció de aromatització de metà (MDA) com alternativa per a l'obtenció d'aromàtics. El catalitzador més emprat per a esta reacció és el Mo/H-ZSM-5. Per la qual cosa s'ha estudiat la influència de diversos paràmetres en l'activitat catalítica (propietats fisicoquímiques de la zeolita de partida i mètode de incorporació del component metàl·lic) amb l'objectiu de buscar el catalitzador òptim de Mo/ZSM-5. Este estudi ha permès correlacionar els dos tipus de centres actius involucrats en esta reacció amb la conversió de metà y la formació de productes. Un del grans inconvenients que presenta esta reacció és la forta desactivació que sofreix el catalitzador, per la qual cosa s'ha realitzat un estudi de les possibilitats de regeneració d'aquest, el que ha permès dissenyar un protocol de treball útil per allargar la vida del catalitzador i ampliar les seves possibilitats d'aplicació a nivell industrial. A més a més, s'ha estudiat l'ús d'altres materials zeolítics amb estructura de porus mitjà i multiporo com possibles alternatives a la ZSM-5, i s'ha correlacionat el seu comportament catalític amb les diferents topologies. Dins del marc de les reaccions de transformació i redistribució d'aromàtics (BTX), s'han estudiat reaccions per l'obtenció d'alquilaromàtics de gran interès per a la indústria petroquímica, com són xilè, etilbenzè, cumè, etiltoluè i cimè, mitjançant reaccions d'alquilació, desproporcionació o isomerització, on s'impliquen zeolites com catalitzadors àcids. Les zeolites principalment utilitzades en aquests processos a escala industrial són ZSM-5, MCM-22, Beta i MOR. Per tant, s'han estudiat nous materials zeolítics com a catalitzadors alternatius en estos processos, tenint en compte les dimensions moleculars dels reactants, productes i intermedis de reacció requerits, conjuntament amb les dimensions topològiques de les estructures zeolítiques. També s'han inclòs en este estudi zeolites multiporo, molt interessants per permetre controlar el tràfic molecular a través de les diferents obertures dels seus canals. En estos processos reactius, han destacat les zeolites ITQ-13, ITQ-22, ITQ-39 i ITQ-47 per presentar un bon comportament catalític, plantejant-se com a possibles alternatives als catalitzadors emprats a escala industrial.
Portilla Ovejero, MT. (2015). Zeolitas para la obtención y redistribución de aromáticos en la fracción BTX [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59471
TESIS
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Strandberg, Christoffer. "Geoenergilösning för DN-huset." Thesis, Uppsala universitet, Institutionen för fysik och astronomi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-227599.
Повний текст джерелаАнотація:
In this thesis proposals for different designs of a borehole thermal energy storage (BTES) have been developed for the building DN-huset in Stockholm, Sweden. To build a BTES results in savings in energy costs by approximately 44 %, i.e. 2 million Swedish crowns annually. Furthermore, a BTES would reduce the annual environmental impact with roughly 75-157 tonnes of CO2 equivalents per year, depending on how the electricity consumption’s environmental impact is estimated. The payback period is about 11 years, including the warm-up period that is necessary before commissioning the BTES. The savings in environmental impact and operating costs are a result of energy being reused. During the summer heat is stored in the bedrock beneath the building for retrieval about half a year later in the winter, when there is a heating demand. In addition to developing proposals for different BTES designs the thesis also examines the influence of certain design parameters, conservative choices and operating conditions.
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Venegas, Picón Luis Alberto. "Generación de una trama Broadcast Transport Stream (BTS) usando el software libre Opencaster." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2012. http://tesis.pucp.edu.pe/repositorio/handle/123456789/1393.
Повний текст джерелаАнотація:
La presente tesis consiste en la generación de una trama Broadcast Transport
Stream (BTS) con contenido de audio, video y datos, así como, la generación de
una trama con una aplicación interactiva embebida utilizando el software libre
OpenCaster.
Se inició con el análisis del diagnóstico del problema que motivo el desarrollo de
esta tesis, buscando explicar el marco actual de la televisión digital terrestre en el
Perú y una breve descripción de su problema económico debido a su
infraestructura. A continuación, se describen las tecnologías involucradas en el
sistema donde se estudió a detalle el funcionamiento de las tablas PSI (Program
Specific Information) para su posterior diseño en software.
Luego, se realizó el diseño de los inputs necesarios antes de la mutiplexación de
paquetes para la generación del BTS. A continuación, se describió la arquitectura
del sistema generador del BTS así como también especificaciones del software libre
a usar para la multiplexación: OpenCaster. Posteriormente, se procedió con la
generación de la trama BTS en 3 escenarios: con un servicio de TV digital SD, 2
servicios de TV digital SD y un servicio SD con una aplicación interactiva (GINGA)
embebida.
Finalmente, se realizaron las pruebas de las tramas BTS generadas por medio de
un analizador de tramas. Para los servicios de TV digital SD también se hizo
pruebas en un escenario IP. Además, se hicieron conclusiones de la presente
tesis, algunas recomendaciones y sugerencias para trabajos futuros que permitirán
profundizar el tema de investigación sobre sistemas de TV digital basados en
software libre.Tesis
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Luz, Adriana Dervanoski da. "Aplicação de processos adsortivos na remoção de compostos BTX presentes em efluentes petroquímicos." Florianópolis, SC, 2009. http://repositorio.ufsc.br/xmlui/handle/123456789/92423.
Повний текст джерелаАнотація:
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Química.Made available in DSpace on 2012-10-24T08:45:18Z (GMT). No. of bitstreams: 1 262204.pdf: 2856838 bytes, checksum: 63d375ca3efc0ccfa6ed58506277917d (MD5)
Muitos compostos orgânicos tóxicos estão presentes nos efluentes das indústrias petroquímicas, especialmente hidrocarbonetos de difícil remoção, tais como os compostos BTX (benzeno, tolueno e o-xileno). Estes compostos apresentam um elevado potencial de contaminação, representando um sério risco ao meio ambiente e ao homem, sendo que o benzeno é considerado o mais tóxico, devido ao seu potencial carcinogênico e mutagênico. Atualmente o aumento da preocupação com as questões ambientais, bem como o maior rigor da legislação no despejo de contaminantes em corpos receptores tem incentivado a busca por novas tecnologias para o tratamento de efluentes industriais que contenham tais contaminantes. Destas tecnologias o método de adsorção oferece o método mais efetivo, pois este consegue alcançar o limite estabelecido pela resolução do CONAMA para a concentração do descarte nos corpos d'água. As condições favoráveis para operar plantas industriais que visam à adsorção de compostos químicos podem ser preditas através da modelagem matemática e simulação numérica dos fenômenos envolvidos. No presente trabalho é utilizado um modelo fenomenológico que descreve o processo de remoção dos compostos BTX através da adsorção em uma coluna de leito fixo, utilizando-se carvão ativado como adsorvente. Os parâmetros cinéticos e de equilíbrio termodinâmico foram obtidos experimentalmente em reatores batelada para os compostos BTX mono e multicomponente, onde a competitividade por sítio ativo de adsorção também foi investigada. Os ensaios experimentais mostraram que, dos três compostos estudados, o o-xileno é o contaminante mais competitivo pelo sítio ativo de adsorção. Este fato está ligado à interação com a superfície do material, peso molecular e solubilidade dos compostos. O modelo considera as resistências de transferência de massa interna e externa à partícula do adsorvente. As equações foram discretizadas utilizando o método de Volumes Finitos com função de interpolação UDS e CDS. Através do algoritmo computacional desenvolvido em linguagem FORTRAN, foi realizada uma análise de sensibilidade paramétrica das condições operacionais do processo de adsorção. Os resultados obtidos pela simulação apresentaram boa concordância quando comparados com dados experimentais encontrados na literatura. Os resultados das simulações mostraram que todos os parâmetros avaliados influenciam na adsorção dos compostos BTX, e que o modelo matemático e a metodologia numérica podem ser usados como uma ferramenta para prever o comportamento dinâmico e estacionário do processo de adsorção utilizados para determinar as condições economicamente ótimas de uma coluna de adsorção em leito fixo de adsorvente.
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Parreira, Adriano Guimarães. "Consórcio bacteriano para biorremediação de solo contaminado com gasolina." Universidade Federal de Viçosa, 2005. http://www.locus.ufv.br/handle/123456789/8062.
Повний текст джерелаАнотація:
Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2016-06-27T15:31:26Z
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Cinqüenta e dois isolados microbianos pertencentes ao Laboratório de Biodiversidade e Biotecnologia para o Meio Ambiente (LBBMA) do Departamento de Microbiologia, Universidade Federal de Viçosa, Viçosa, MG, foram avaliados quanto à capacidade de crescimento em gasolina pura, gasolina adicionada de 25% de etanol, benzeno, tolueno e xilenos. A capacidade de produzirem biossurfactante em substrato contendo gasolina comercial como fonte de carbono foi também avaliada. Os 16 isolados que apresentaram crescimento considerado satisfatório em meio suplementado com gasolina pura foram avaliados quanto à capacidade de utilização de benzeno, tolueno ou xileno (BTX) como fontes exclusivas de carbono. Os quatro melhores foram selecionados para comporem um consórcio microbiano a ser estudado em biorreatores construídos para esse fim, sendo identificados pela análise de ésteres metílicos de ácidos graxos (FAME) como sendo: Stenotrophomonas maltophilia (isolado BBMA 105A), Sphingomonas capsulata (isolado LBBMA 178b) e Pseudomonas balearica (isolado LBBMA 193).O isolado BBMA B1 encontra-se em vias de identificação. Além desses, o isolado LBBMA 53A, identificado como Pseudomonas aeruginosa e o isolado LBBMA 178, também pertencente ao gênero Pseudomonas, foram selecionados por serem os mais eficazes quanto à produção de biossurfactantes. A identificação de S. capsulata como degradadora de tolueno e de P. balearica como degradadora de xileno, representa o acréscimo de mais uma característica metabólica relevante na descrição dessas espécies. O estudo da otimização do processo de biorremediação de amostra de solo contaminado com gasolina em biorreatores, considerando as variáveis fornecimento de oxigênio, fornecimento de nutrientes minerais e inoculação do consórcio bacteriano, permitiu a seleção das condições propícias à degradação de BTX pelo consócio microbiano selecionado. O consórcio microbiano demonstrou ser eficiente na biorremediação de solo contaminado com gasolina comercial. A utilização de um composto liberador de oxigênio não foi eficiente em estimular a biodegradação de hidrocarbonetos. A injeção de ar foi comprovadamente a melhor forma de suprimento de oxigênio ao processo de biorremediação conduzido em birreatores. A inoculação do slurry com o consórcio selecionado neste trabalho promoveu um aumento significativo da degradação dos componentes da gasolina, em especial BTX, demonstrando ser uma estratégia promissora para a biorremediação de solos contaminados com gasolina.
Fifty two microbial isolates belonging to the Laboratory of Biodiversity and Biotechnology for the Environment (LBBMA), of the Department of Microbiology of the University of Viçosa, Viçosa, MG, were evaluated for their capacity to grow in gasohol (ethanol 25%), benzene, toluene and xylenes. The producing biosurfactants in mineral medium with gasohol sole carbon source was also evaluated. Among the 52 isolates, 16 were able to grow satisfactory in gasohol mineral medium. These isolates were evaluated further for their capacity to use benzene, toluene or xylenes (BTX) as sources of carbon. Four isolates were selected to be part of a bacterial consortium for bioremediation of gasohol contaminated soil in bioreactors. These isolates were identified by fatty acid methyl ester (FAME) analysis as: Stenotrophomonas maltophilia (LBBMA 105A), Sphingomonas capsulata (LBBMA 178b) Pseudomonas balearica (LBBMA 193). The isolate LBBMA B1 is under identification. Isolates LBBMA 53A, identified as Pseudomonas aeruginosa and LBBMA 178, a Pseudomonas sp., were also selected as efficient biosurfactant producing members of the microbial consortium. The identification of S. capsulata as able to use toluene and of P. balearica as able to use xylene, represents the inclusion of another relevant metabolic characteristic for the description of these species. The optimization of the bioremediation of soil samples contaminated with gasohol in bioreactors, allowed the selection of the most appropriate conditions for the degradation of BTX by the selected bacterial consortium. Microbial consortium was found to be efficient in bioremediation of soil contaminated with brazilian gasohol. The use of an oxygen-releasing compound was not efficient in stimulating biodegradation of hydrocarbons. Air injection was proved to be the best way of supplying oxygen to the bioremediation process carried out in the bioreactor. Inoculation of contaminated soil slurry with the consortium in this work significantly increased the degradation of the gasoline components, especially BTX. Our data demonstrated that the use of the selected consortium in adequately-operated bioreactors is a promising strategy for bioremediation of soils contaminated with gasohol.
Dissertação antiga
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Řehák, Martin. "Návrh rádiové sítě GSM-R na železniční trati včetně návrhu konektivity k základnovým stanicím BTS." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-316432.
Повний текст джерелаАнотація:
This diploma thesis deals with the design of the radio network for the track section Břeclav-Znojmo. Firstly, the theoretical knowledge about GSM-R, Radiolab and radio relay is described. The next part deals with the measurement of the already covered section of the track and the selection of a suitable propagation model. Radiolab is designed to cover several diffusion models. The model used for the final design of the network is chosen based on the comparison of the measurement results with the proposed coverage in Radiolab. The last part describes the provision of connectivity to individual base stations. Several connectivity options are compared.
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Gendron, Bénédicte. "Les diplômés d'un BTS et d'un DUT et la poursuite d'études : une analyse économique /." Paris : Publications de la Sorbonne, 2004. http://catalogue.bnf.fr/ark:/12148/cb392394167.
Повний текст джерелаАнотація:
Texte remanié de: Th. doct.--Sci. écon.--Paris 1, 1997. Titre de soutenance : D'une stratégie de formation à une stratégie d'employabilité, analyse de la poursuite d'études après un BTS ou un DUT.BTS = Brevet de technicien supérieur. DUT = Diplôme universitaire de technologie. Bibliogr. p. 245-261.
44
Alm, Micael. "Probability Modelling of Alpine Permafrost Distribution in Tarfala Valley, Sweden." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-323971.
Повний текст джерелаАнотація:
Datainsamling har genomförts i Tarfaladalen under 5 dagar vid månadsskiftet mellan mars och april 2017. Insamlingen resulterade i 36 BTS-mätningar (Bottom Temperature of Snow cover) som därefter har använts tillsammans med data från tidigare insamlingar, till att skapa en sammanställd modell över förekomsten av permafrost omkring Tarfala. En statistisk undersökning syftade till att identifiera meningsfulla parametrar som permafrost beror av, genom att testa de oberoende variablerna mot BTS i en stegvis regression. De oberoende faktorerna höjd över havet, aspekt, solinstrålning, vinkel och gradient hos sluttningar producerades för varje undersökt BTS-punkt i ett geografiskt informationssystem. Den stegvisa regressionen valde enbart höjden som signifikant variabel, höjden användes i en logistisk regression för att modellera permafrostens utbredning. Den slutliga modellen visade att permafrostens sannolikhet ökar med höjden. För att skilja mellan kontinuerlig, diskontinuerlig och sporadisk permafrost delades modellen in i tre zoner med olika sannolikhetsspann. Den kontinuerliga permafrosten är högst belägen och därav den zon där sannolikheten för permafrost är störst, denna zon gränsar till den diskontinuerliga permafrosten vid en höjd på 1523 m. Den diskontinuerliga permafrosten har en sannolikhet mellan 50–80 % och dess undre gräns på 1108 m.ö.h. separerar den diskontinuerliga zonen från den sporadiska permafrostenA field data collection has been carried out in Tarfala valley at the turn of March to April 2017. The collection resulted in 36 BTS-measurements (Bottom Temperature of Snow cover) that has been used in combination with data from earlier surveys, to create a model of the occurrence of permafrost around Tarfala. To identify meaningful parameters that permafrost relies on, independent variables were tested against BTS in a stepwise regression. The independent variables elevation, aspect, solar radiation, slope angle and curvature were produced for each investigated BTS-point in a geographic information system. The stepwise regression selected elevation as the only significant variable, elevation was applied to a logistic regression to model the permafrost occurrence. The final model showed that the probability of permafrost increases with height. To distinguish between continuous, discontinuous and sporadic permafrost, the model was divided into three zones with intervals of probability. The continuous permafrost is the highest located zone and therefore has the highest likelihood, this zone delimits the discontinuous permafrost at 1523 m a.s.l. The discontinuous permafrost has probabilities between 50-80 % and its lower limit at 1108 m a.s.l. separates the discontinuous zone from the sporadic permafrost.
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Souza, Daniela Tidre. "REMEDIAÇÃO DE SOLO CONTAMINADO COM GASOLINA VIA PROCESSO TIPO-FENTON E AVALIAÇÃO DA TOXICIDADE." Universidade Estadual de Ponta Grossa, 2017. http://tede2.uepg.br/jspui/handle/prefix/2420.
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A contaminação dos solos pelo derramamento de gasolina é um grande problema ambiental, principalmente devido aos hidrocarbonetos constituintes da gasolina como o benzeno, tolueno e xilenos. Desta forma, estudos de técnicas modernas de remediação de áreas contaminadas são de grande importância. Os Processos Oxidativos Avançados (POAs) são muito aplicados na remediação de áreas contaminadas com hidrocarbonetos, dentre estas, destaca-se o processo tipo-Fenton, esse processo consiste basicamente da decomposição do peróxido de hidrogênio catalisado por íons Fe3+, onde também pode ser catalisado pelas formas minerais de ferro presente no solo. Em decorrência disso, este trabalho teve como objetivo avaliar e comparar a eficiência do processo tipo-Fenton com adição de Fe3+ e utilizando o ferro mineral, assim como, avaliar o efeito da presença de etanol na gasolina durante o tratamento e a fitotoxicidade. Para as determinações utilizou-se cromatografia gasosa acoplada ao sistema de headspace, onde também houve uma extração prévia associando a adição de cloreto de sódio, vortex e ultrassom, apresentando índices de recuperação entre 79,25% a 108,41% para o benzeno. A determinação dos BTX via CG-headspace mostrou-se um método confiável uma vez que na faixa linear estudada (0,05 a 80 mg Kg-1) apresentou boa linearidade com R2=0,9989 para o benzeno e a precisão avaliada ficou entre 0,87 e 3,18%. Os resultados obtidos dos estudos de degradação mostraram que os processos foram eficientes na remoção dos BTX. Para as reações com adição de ferro (Fe3+) a redução dos BTX foi maior que 93 ± 0,08% e 91 ± 0,24% para as gasolinas com e sem etanol, respectivamente após 120 minutos de reação. E para as reações utilizando apenas o ferro mineral, a remoção foi maior que 89 ± 0,78% e 67 ± 0,49% com etanol e sem etanol. Evidenciando a eficiência dos óxidos de ferro presentes nessa amostra de solo. Apesar da elevada eficiência na remoção dos BTX, os ensaios de fitotoxicidade realizados após o tratamento com sementes de Lactuca sativa mostraram aumento na fitotoxicidade. Os resultados mostraram que após o tratamento e independente do processo utilizado não ocorreu germinação das sementes. Desta forma, os resultados indicam que subprodutos formados durante a degradação, apresentam maior toxicidade frente ao bioindicador Lactuca sativa. Desta forma, embora os processos de remediação utilizados neste estudo mostrarem ser eficientes na remoção dos BTX (remoção > 67%), o tempo do tratamento de 120 minutos não é o suficiente para remover a fitotoxicidade.
The contamination of soils by gasoline spills is a biggest environmental problem, mainly due to the hydrocarbons that derived from gasoline such as benzene, toluene and xylene. In this way, studies of modern remediation techniques of contaminated areas are important. The Advanced Oxidative Processes (AOPs) have are widely employed in remediation of areas contaminated by hydrocarbons, among the Fenton-type process, which has been used quite frequently in soil remediation. This process basically consists of the decomposition of hydrogen peroxide catalyzed by Fe3+ ions, and this process can also be catalyzed by the mineral forms of iron present in the soil. As a result, this work had as objective to evaluate and compare the efficiency of the Fenton-type process with addition of Fe3+ and using the mineral iron. As well as evaluating the effect of the presence of ethanol in gasoline during treatment and the phytotoxicity. For the determinations, gas chromatography coupled to the headspace system was used, where there was also a previous extraction associating the addition of sodium chloride, vortex and ultrasound, presenting recovery rates between 79,25% and 108,41% for benzene. The determination of BTX through CG-headspace proved to be a reliable method since in the studied linear range (0,05 to 80 mg Kg-1) showed good linearity with R2= 0.9989 for benzene and the precision evaluated was between 0,87 and 3,18%. The results obtained from the degradation studies showed that the processes were efficient in the removal of BTX. The obtained results showed that the processes were efficient in the removal of BTX. For reactions with iron addition (Fe3+) the reduction of BTX was greater than 93 ± 0,08% and 91 ± 0,24% for gasolines with and without ethanol, respectively after 120 minutes of reaction. And for reactions using only mineral iron, the removal was greater than 89 ± 0.78% and 67 ± 0.49% with ethanol and without ethanol, respectively. Evidence for the efficiency of iron oxides present in this soil sample. Despite the high efficiency of BTX removal, the phytotoxicity tests performed after treatment with Lactuca sativa seeds showed an increase in phytotoxicity. The results showed that after the treatment and regardless of the process used no germination of seeds occurred. Thus, the results indicate that by-products formed during degradation, present higher toxicity to the bioindicator Lactuca sativa. Thus, although the remediation processes used in this study prove to be efficient in removing BTX (removal> 67%), the treatment time of 120 minutes is not enough to remove phytotoxicity.
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Gomez-Rivera, Francisco. "Exploration of Biological Treatment Systems for the Removal of Persistent Landfill Leachate Contaminants and Nanoparticles." Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/145311.
Повний текст джерелаАнотація:
The integrity of groundwater sources is constantly threatened by contaminant plumes generated by accidental gasoline leakages and leachates escaping landfills. These plumes are of concern due to their proven toxicity to living organisms. Aromatic and chlorinated hydrocarbons, volatile fatty acids, phenols, and ammonia have been found in these leachates. In addition, benzene, toluene, and xylenes (BTX) are major components of gasoline. The lack of oxygen in groundwater makes anaerobic bioremediation desired for the treatment of groundwater contaminated with BTX and chlorinated solvents. With the objective of finding microorganisms capable of BTX and cis-dichloroethylene (cis-DCE) degradation under anaerobic conditions for their use in permeable reactive barriers, different inocula were tested in batch experiments. Toluene was rapidly degraded by several inocula in the presence of alternative electron acceptors. Benzene and m-xylene were eliminated by few of the inocula tested after incubation periods ranging from 244 to 716 days. cis-DCE was highly recalcitrant as no degradation was observed over 440 days. Biological processes have been successfully applied for the treatment of landfill leachates as well. In an effort to provide an effective and economical alternative, an anaerobic-aerobic system was evaluated using a synthetic media simulating the organic and ammonia content of real leachates. The removal of the organic content reached 98% in an upflow anaerobic sludge blanket reactor, and resulted in the formation of methane. During the aerobic process, in an innovative down-flow sponge reactor, ammonia was highly transformed to nitrite and nitrate. Complete nitrification was eventually achieved.The capacity of current wastewater treatment plants for removing nanoparticles has been questioned during the last years. Nanoparticles have been incorporated into numerous applications and their presence in wastewater seems to be inevitable. A laboratory-scale secondary treatment system was set-in to study the behavior of cerium and aluminum oxide nanoparticles during wastewater treatment. The nanoparticles were highly removed, suggesting that secondary treatment is suitable for their elimination. The removal of these nanoparticles was influenced by the pH and organic content of the wastewater. Aluminum nanoparticles proved to be toxic; however the performance of the system for eliminating the organic content was recovered over time.
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Carhuamaca, Espinoza Andrés Erasmo. "Diseño del sistema de transmisión satelital para el transporte de la señal ISDB-T BTS." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2012. http://tesis.pucp.edu.pe/repositorio/handle/123456789/1449.
Повний текст джерелаАнотація:
El presente proyecto de tesis consiste en el diseño del sistema de transmisión satelital
para el transporte de la señal de Televisión Digital Terrestre (TDT) a provincias de
manera que éste sirva como modelo de referencia, para las empresas emisoras de
contenido, que deben iniciar este tipo de transmisiones en los próximos años.
El primer capítulo muestra el estado del arte de la TDT, en donde se identifican las
consideraciones generales como antecedentes en el Perú, implementación en otros
países y el despliegue actual en nuestro país. También se hará una evaluación de la
legislación vigente sobre el desarrollo de la TDT.
El segundo capítulo contempla el estudio de las tecnologías relacionadas con la TDT
como el estándar Transmisión Digital Terrestre de Servicios Integrados (Integrated
Services Digital Broadcasting Terrestrial – ISDB-T) y, en especial, el estándar para
transmisión satelital DVB-S2. También se hará un estudio de la señal Broadcast
Transport Stream (BTS) que encapsula las señales: High Definition (HD), Standard
Definition (SD) y One-Seg.
El tercer capítulo involucra el método que se utilizará para remultiplexar la señal ISDBT
BTS de manera que se logre reducir considerablemente su elevada tasa de bits.
También se mostrarán los resultados obtenidos en Brasil con el método, bajo
diferentes configuraciones de prueba.
En el cuarto capítulo se plasmará el diseño del sistema de transmisión satelital para
transportar la señal ISDB-T BTS desde las estaciones de emisión en Lima hasta las
estaciones retransmisoras en provincias. Se detallarán también todos los equipos
involucrados en la solución y las consideraciones necesarias para la operación de los
mismos.
El quinto capítulo se enfoca en un análisis económico de la solución propuesta y se
compara los costos de alquiler de espectro que las empresas emisoras de contenido
tendrán que afrontar, utilizando el método de remultiplexado y sin éste.Tesis
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Souza, Renata dos Santos 1982. "Avaliação da lama vermelha na remoção de derivados de petróleo - benzeno, tolueno e xileno (BTX)." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266619.
Повний текст джерелаАнотація:
Orientador: Meuris Gurgel Carlos da SilvaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
Made available in DSpace on 2018-08-22T16:47:28Z (GMT). No. of bitstreams: 1 Souza_RenatadosSantos_D.pdf: 2889400 bytes, checksum: 692c0c9b405b4f550e07f530c56c124c (MD5) Previous issue date: 2013
Resumo: Muitos compostos orgânicos derivados do petróleo são encontrados na água subterrânea, oriundos de processos industriais ou, principalmente, dos vazamentos de combustível em postos de distribuição. Dentre esses compostos encontram-se benzeno, tolueno e xileno (BTX), substâncias tóxicas e carcinogênicas e que se constituem nos componentes mais poluidores da gasolina. Processos de remoção dos BTX devem atender aos limites da legislação e, nesse sentido, a adsorção é um dos métodos mais eficientes. Neste trabalho foi proposto avaliar a lama vermelha, resíduo da indústria de beneficiamento do alumínio, nas formas bruta, calcinada e quimicamente tratada, como material adsorvente alternativo para remoção dos BTX em soluções sintéticas com um e dois adsorbatos. A caracterização da lama vermelha indicou que o material é macroporoso, muito heterogêneo e constituído de uma mistura de óxidos principalmente sodalita, hematita, goetita, gibbsita e quartzo. A calcinação provocou alterações na estrutura do adsorvente, aumentando a área superficial e a quantidade e tamanho de macroporos. O estudo do pHzpc mostrou que o pH natural da lama vermelha tornou a superfície carregada negativamente, atraindo assim o anel benzênico e melhorando a adsorção. Os ensaios de cinética de adsorção mostraram um processo rápido com no máximo 2h para atingir o equilíbrio e o percentual de remoção foi acima de 85% para todos os compostos. Nos ensaios de equilíbrio com monocomposto a ordem decrescente de adsorção foi benzeno, tolueno e xileno. As maiores capacidades de adsorção de benzeno foram qe = 0,332 mmol/g com lama bruta, e com lama calcinada qe = 0,335 mmol/g, esses valores são elevados quando comparados com adsorventes do tipo argilominerais. Os modelos Langmuir com dois sítios e múltiplos espaços de adsorção foram os que melhor se ajustaram aos resultados experimentais de adsorção com monocomposto, porém não conseguiram prever as multicamadas existentes nas isotermas. Foi verificada uma diminuição na remoção de todos os BTX na condição de mistura binária. A ordem de remoção de BTX foi inversa e com maiores remoções de xileno (qe = 0,3406 mmol/g). O modelo de Langmuir se ajustou adequadamente aos resultados experimentais, nessa condição
Abstract: Many organic compounds derived from oil are found in groundwater from industrial processes or specially from leaks at fuel tanks in gas stations. Among these compounds are benzene, toluene and xylene (BTX), toxic and carcinogenic substances that are the most polluters compounds from gasoline. BTX removal processes must attend to legislation limits and thus the adsorption process is one of the most efficient methods. In this work it was used red mud, an aluminum industry waste, in the raw, calcined forms and chemically treated forms, as an alternative adsorbent, to remove the BTX from single and two-component aqueous solutions. The characterization of the red mud indicated that this material is macroporous, very heterogeneous and compound from an oxides mixture, mainly sodalite, hematite, goethite, gibbsite and quartz. The calcination caused changes in the adsorbent structure, increasing the superficial area and the macroporous quantities and size. The pHpzc study showed that the natural red mud pH lets the surface negatively charged, attracting then the benzene rings and improving the adsorption. The kinetic adsorption showed a fast process that needs 2 h to achieve the equilibrium and a removal percentage of 85% for all compounds. In the single component equilibrium studies the adsorption order was benzene, toluene e xylene. The maximum adsorption capacities were qe = 0,332 mmol/g on raw red mud (RM), and on calcined red mud (CRM), qe = 0,335 mmol/g. DSL and MSAM models were the best fit to the experimental data in the single component adsorption, although they could not to predict the multiple layers existing in the isotherms. It was verified a decrease in the removal of all BTX in the two-component adsorption. There was a change in the BTX removal order and more removal of xylene (qe = 0,3406 mmol/g). The Langmuir model showed good fit to the experimental data in this condition
Doutorado
Engenharia de Processos
Doutora em Engenharia Quimica
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Jaoua, Aïda. "La finance peut-elle être solidaire ? : le cas de la Banque Tunisienne de Solidarité "BTS"." Thesis, Reims, 2011. http://www.theses.fr/2011REIME001/document.
Повний текст джерелаАнотація:
Cette thèse s'inscrit dans une approche institutionnelle d'incitation à la création d'entreprises. La problématique développée porte sur l'analyse des critères de sélection et de financement qu'utilise la première institution de solidarité à la création d'entreprises en Tunisie "la Banque Tunisienne deSolidarité (la BTS)". L'objectif de cette recherche est d'identifier les critères de sélection explicites et implicites utilisés par la BTS pour l'octroi de crédits aux créateurs potentiels "les diplômés de l'enseignement supérieur" et à comparer ces critères à ceux d'autres institutions de financement de l'entrepreneuriat (Benchmarking). Le travail propose un modèle de financement des nouvelles entreprises et sa validation à travers le cas de la BTS dans deux régions différentes (une étude comparative). La recherche montre que la BTS utilise dans sa méthodologie d'octroi de crédits des critères liés à l'entrepreneur et ceux qui sont liés à son projet. En outre, l'environnement exerce une influence sur le choix de ces critères. Dans le cadre de financement des nouvelles entreprises, la confiance semble une condition sine qua non. Une étude qualitative est proposée pour vérifier si les cadres de la BTS l'adoptent effectivement dans leur stratégie et ce qu'ils mettent comme sens derrière ce critèreThis thesis is an institutional approach to the incentive entrepreneurship. The problem developed focuses on the analysis of selection criteria and financing used by the first institution solidarity with the creation of enterprises in Tunisia Tunisian Bank Solidarity (BTS).The objective of this research is to identify the selection criteria explicit and implicit use by the BTS for granting credits to the creators potential "graduates of higher education" and to compare these criteria to other financial institutions of entrepreneurship (Benchmarking). The work proposes a new funding model business and its validation through the case of the BTS in two regions different (comparative study). Research shows that the BTS uses in its methodology for granting credit-related criteria to the contractor and those related to the project. Moreover, the environment influences the choice of these criteria. As part of financing new companies, trust seems to be a sine qua non. A qualitative study is proposed to check whether executives actually adopt the BTS in their strategy and what they bring as sense behind this criterion
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Pablo, Carranza. "LA DUALITE DE LA PROBABILITE DANS L'ENSEIGNEMENT DE LA STATISTIQUE. UNE EXPERIENCE EN CLASSE DE BTS." Phd thesis, Université Paris-Diderot - Paris VII, 2009. http://tel.archives-ouvertes.fr/tel-00458320.
Повний текст джерелаАнотація:
Dans ce travail de thèse, nous nous intéressons aux possibilités de sensibiliser à la dualité de la probabilité dans l'enseignement en France. Pour cela nous avons organisé cette présentation en quatre parties. La première est consacrée à une enquête épistémologique, la deuxième à une analyse de manuels, la troisième à un ensemble d'expérimentations effectuées en BTS et finalement dans la quatrième nous donnerons quelques conclusions et perspectives qui découlent de notre travail.