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Sauveur, Stephen Charles. "Estimation of phosphorus contributed to lakes from on-site sewage disposal systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0021/MQ48287.pdf.
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Tsukuda, Seigen. "A study on amount and sources of atmospheric phosphorus deposition for estimation of net atmospheric phosphorus input to terrestrial ecosystems." Kyoto University, 2005. http://hdl.handle.net/2433/145024.
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Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(農学)<br>甲第11623号<br>農博第1479号<br>新制||農||906(附属図書館)<br>学位論文||H17||N4016(農学部図書室)<br>23266<br>UT51-2005-D372<br>京都大学大学院農学研究科森林科学専攻<br>(主査)教授 竹内 典之, 教授 小﨑 隆, 助教授 杉山 雅人<br>学位規則第4条第1項該当
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Spaetzel, Alana Burton. "Investigating uncertainty of phosphorus loading estimation in the Charles River Watershed, eastern Massachusetts." Thesis, Boston College, 2018. http://hdl.handle.net/2345/bc-ir:108213.
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Thesis advisor: Noah P. Snyder<br>Estimating annual phosphorus (P) loading in impaired fresh water bodies is necessary to identify and prioritize management activities. A variety of monitoring programs and water quality models have been developed to estimate P loading in impaired watersheds. However, uncertainty associated with annual riverine P loads tends to receive less attention. This study addresses this gap by exploring the range in annual total phosphorus (TP) loads from two common load estimation methods using data collected in the Charles River watershed (CRW) in eastern Massachusetts. The CRW has two P Total Maximum Daily Load (TMDL) reports due to impairments with respect to excessive summer algal growth. Three estimation methods are used in this thesis to quantify annual TP loads (LY): the concentration-discharge relationship (CQ), the land use coefficient (LUC) method, and the average concentration, continuous discharge (ACQ) method. LY derived using the LUC method spanned an average relative percent range of 214% at each site, whereas LY results from the concentration-discharge method spanned an average relative percent range of 56%. While results of the CQ method produced a narrower range of LY, the CQ relationship is subject to seasonal dependencies and inconsistency through time. Seasonal terms in the LOADEST program, a publicly available and commonly used statistics tool, do allow the model estimates to capture trends through time, an advantage over the LUC method. Results of an interlaboratory comparison of P concentrations demonstrate the potentially large role of analytical uncertainty in LY estimation. Significant discrepancies between the results of each method for a single location and time suggest that loading estimates and consequently management priorities may be dependent on the estimation technique employed<br>Thesis (MS) — Boston College, 2018<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Earth and Environmental Sciences
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Leitch, Katherine McArthur. "Estimating Tributary Phosphorus Loads Using Flow-Weighted Composite Storm Sampling." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/10078.
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Quantification of total phosphorus (TP) loads entering a lake or reservoir is important because phosphorus is most often the limiting nutrient in terms of algae growth, thus phosphorus can control the extent of eutrophication. Four methods for assessing the annual tributary phosphorus loads to two different Virginia reservoirs were analyzed, three methods that use tributary monitoring program data and one that uses land-use and rainfall data. In this project, one tributary has been extensively monitored for many years and served as a control on which the other methods were tested. The key difference between this research and previous studies is the inclusion of flow-weighted composite storm sampling instead of simple grab sample analyses of storm flow. Three of the methods employed flow stratification, and the impact of the base flow separation point was examined. It was found that the Regression Method developed in this research was the least sensitive to the base flow separation point, which is a valuable attribute because a wrong choice will not significantly affect the estimate. The Monte Carlo Method was found to underestimate the TP loads. The amount of rainfall impacted the accuracy of the methods, with more error occurring in a year with lower precipitation.<br>Master of Science
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Jarrett, Jamie Pearl. "Improving estimations of phosphorus bioavailability for lactating dairy cows." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/77248.
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Phosphorus (P) is an instrumental nutrient in numerous physiological processes, but can have detrimental environmental impact if fed in excess. Increased P intake in dairy cows leads to increased fecal excretion of P and a reduction in efficiency of use. Variability in P concentration or availability in feedstuffs can exacerbate P excretion. To investigate variability in P between and within feedstuffs, 170 feed samples (forages, concentrates, and by-products), were collected from across the U.S., classified by region fed, and analyzed for total P, inorganic P, and phytate. Forages contained a greater proportion of P in the inorganic form and less total P and phytate as compared to concentrates and by-products. The majority of total P (71.2, 81.8, and 81.9% of total P in forages, concentrates, and by-products, respectively) was associated with inorganic P and phytate. The enzyme phytase has been used successfully in swine and poultry nutrition, as a feed additive, to increase available P and reduce the need for supplemental inorganic P. An experiment was conducted to investigate the effect of phytase use and forage particle length, using a 2 x 2 factorial, on P availability in lactating dairy cows. Total P intake of the four diets was similar (P > 0.15). Total tract digestibility of total P tended (P < 0.10) to be reduced and total P excretion was increased (P < 0.05) with phytase supplementation. Milk fat yield, protein yield, 3.5% FCM, and ECM were increased (P < 0.05) with addition of exogenous phytase to the diet. This indicates that phytate may contain some anti-nutritional factors that reduce availability in other nutrients used for milk production. Variation in P compounds between feeds, and variation in P digestion and production performance with exogenous phytase suggests opportunity for improvement in prediction of P availability from feeds for lactating cows.<br>Ph. D.
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Balcerzak, Ashlee Marie. "Evaluating Long-term Nutrient Impacts within Agricultural Headwater Streams." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1598021048962491.
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Hemmingsson, Christoffer. "Estimating soluble arsenic and phosphorus concentrations under Precambrian oceanic conditions." Thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-107374.
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Original estimates of phosphorus (P) concentrations in the Precambrian oceans before 1.9 Ga gave a budget of ~10-25% of modern day levels. This budget was challenged by accounting for high silica (Si) concentrations that were believed to have outcompeted P for binding sites on precipitating iron oxide-hydroxide particles during the chemical oxidation and burial of iron (Fe). Such iron oxide-hydroxide particles are considered as proxies of ancient iron-rich sedimentary rocks, such as banded iron formations, which are often used to infer the dissolved chemistry of trace elements in the ancient oceans. This study raises the question of wether arsenic (As) had an effect of the binding of P to precipitating iron minerals, during the co-precipitation of Iron oxide- hydroxide in elevated Fe and Si concentrations characteristic of the early oceans. This hypothesis is based on the chemical similarities seen between P and As. Results show a more pH dependent competition between P and AsIII, whereby P outcompetes AsIII at a pH <7. The effect decreases as the pH rises until pH ~8 at which the effect cancels out and AsIII becomes somewhat predominant over P. AsV on the other hand, an analogue to P, is outcompeted by P throughout pH 5-10. Distribution coefficients (Kd) of P on iron oxide-hydroxide particles were not affected by the concentration of Si in solution. Average Kd and standard error between concentrations of Si, across the sample pH of 5-10 revealed an average Kd of 0.072 (±0.01) μM-1. This is strikingly similar to another experimental Kd at 0.075 (±0.003) μM-1, when the effects of Si are excluded. The average Kd in this study is also consistent with the average Kd of 0.06 μM-1 from a range of As-rich hydrothermal systems reported in a previous study, supporting the original idea of Precambrian P levels being low. The average Kd between concentrations of Fe revealed a Kd of 0.12 (±0.03) μM-1 although this was not statistically significant from the average Kd between groups of Si. In addition to low levels of P, the Precambrian oceans likely also contained high levels of As, due to the high hydrothermal activity. This scavenging of P from oceanic waters would have become increasingly important as surface oceans became more oxygenated and the presence of AsV would have been greater. Because the availability of Si does not show any great effect on the uptake of P by precipitating iron oxide-hydroxides, Si concentration is likely not a proxy for oceanic P concentrations. It is proposed that low dissolved P levels are consistent with early oceans that w!ere a lot more hydrothermally influenced than the oceans of today.<br>Prekambriska fosfor (P) nivåer var ursprungligen estimerade till ca 10-25% utav koncentrationen funnen i dagens havsvatten. Denna budget blev motsagd i och med att kisel (Si) sades kunna ersätta bundet fosfor på järn oxid-hydroxid partiklar som precipiterade genom kemisk oxidation och sedimentering av järn (Fe). Dessa järn oxid-hydroxid partiklar anses användbara som proxy för formationen av uråldriga järn-rika sedimentära bergarter såsom banded iron formation (BIF), vilka används idag för att bestämma mängden spårämnen i de uråldriga haven. Denna studie ställer frågan huruvida arsenik (As) påverkar mängden P som binder till precipiterande järn mineral under procession av co-precipitering av järn oxid-hydroxid i lösning med förhöjda koncentrationer av Fe och Si, karakteristiska för the uråldriga haven. Denna hypotes är baserad på de kemiska likheter som finns mellan P och As. Resultaten påvisar en pH beroende konkurrens mellan P och AsIII där P utkonkurrerar AsIII vid låg pH. Effekten av denna konkurrans minskar med ökande pH tills effekten blir omvänd omkring pH 8 och P blir istället till viss del utkonkurrerad av AsIII. AsV å andra sedan, en verklig kemisk analog till P, är kontinuerligt utkonkurrerad av P genom alla utförda pH, pH 5-10. Distribueringskoefficienter (Kd) för P på järn oxid-hydroxid partiklar visade ingen påverkan av mängden Si tillgängligt. Medelvärdet av Kd och standard error mellan data av alls pH, grupperat av Si, gav ett värde av 0.072 (±0.01) μM-1. Detta är påfallande nära ett experimentellt framtaget Kd värde av 0.075 (±0.03) μM-1 då effekten av Si är borttagen. Medelvärdet i denna studie är också sammanfallande med det Kd medelvärde man finner idag från olika hydrotemala system av 0.063 (±0.01) μM-1. Detta ger support till den originala idén att de prekambriska haven troligen hade låga halter P tillgängligt. Medelvärdet av Kd mellan koncentrationer av Fe gav ett värde av 0.12 (±0.03) μM-1, dock var detta värde ej statistiskt significant från det Kd utifrån koncentrationer av Si. Förutom de låga nivåer av P i de Prekambriska haven så var det troligen även höga halter av As på grund av utbredd hydrotermal aktivitet. Detta uppfångande av P i de tidiga haven var troligen en alltmer viktigare process då ytvatten blev syrerikare och den oxiderade formen av As, det vill säga AsV hade varit mer vanligt förekommande. Framför allt då den konkurrerande effekten av Si kan bortses när P såväl som As inte påverkas av dess närvaro till den grad man hade trott. Detta gör även att mängden Si troligen inte är en tillförlitlig proxy för att estimera P nivåer i de uråldriga haven. Därmed föreslås det att de prekambriska haven var k!arakteriserade av låga P nivåer, jämfört med idag.
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Andersson, Marcus. "Estimating Phosphorus in rivers of Central Sweden using Landsat TM data." Thesis, Stockholms universitet, Institutionen för naturgeografi och kvartärgeologi (INK), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-77693.
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Phosphorus flowing via rivers into the Baltic Sea is a major source of nutrients, and in some cases the limiting factor for the growth of algae which causes the phenomenon known as eutrophication. Remote sensing of phosphorus, here using Landsat TM-data, can help to give a better understanding of the process of eutrophication. Since Landsat TM-data is used, this could form a basis for further spatio-temporal analysis in the Baltic Sea region. A method originally described and previously applied for a Chinese river is here transferred and applied to three different rivers flowing into the Baltic Sea. The results show that by measuring the proxy variables of Secchi Depth and Chloryphyll-a the remote sensing model is able to explain 41% of the variance in total- phosphorus for the rivers Dalälven, Norrström and Gavleån without any consideration taken to CDOM, turbidity or other local features.
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Jones, Amber Spackman. "Estimating Total Phosphorus and Total Suspended Solids Loads from High Frequency Data." DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/205.
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Frequently measured turbidity was examined as a surrogate for total phosphorus (TP) and total suspended solids (TSS) loads at two locations in the Little Bear River, Utah, USA. Using regression techniques, equations were developed for TP and TSS as functions of turbidity. The equations accounted for censored data, and additional explanatory variables to represent hydrological conditions were considered for inclusion in the equations. By using the resulting surrogate relationships with high frequency turbidity measurements, high frequency estimates of TP and TSS concentrations were calculated. To examine the effect of sampling frequency, reference loads were determined from the concentration records for two water years. The concentration records were artificially decimated to represent various frequencies of manual grab sampling from which annual loads were calculated and compared to the reference loads.
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Herrmann, Inga. "Filter beds for on-site wastewater treatment : Towards more reliable estimations of phosphorus retention." Doctoral thesis, Luleå tekniska universitet, Arkitektur och vatten, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18275.
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Phosphorus (P) is an important plant nutrient and essential for life. However, thephosphate rock used for fertilizer production is a non-renewable resource and itsproduction is expected to peak. At the same time, the discharge of P into naturalwaters is causing eutrophication, a severe problem in areas such as the Baltic Sea. Onsitewastewater treatment facilities in Sweden contribute substantially to this discharge because of their inadequate retention of P. Filter beds are a potentially useful technique to capture P in on-site facilities. However, many variables need to be considered when the P retention of potential filter materials is estimated in laboratory tests prior to designing full-scale filters. The overall aim of this thesis was therefore to increase the reliability of forecasting P retention in full-scale filters by increasing the understanding of P retention in P filters under varying conditions and by identifying measures that could lead to more reliable methods of testing filter materials at laboratory scale.The effects of influent type, influent P concentration, loading rate and ambienttemperature on the filter materials Filtra P, Filtralite P, Top16 and Polonite wereinvestigated in filter column experiments using 22 factorial designs. Furthermore, the P binding mechanism was studied using mineral phase investigations and by determining the reaction time of the P in the filter. In addition, filter performance was estimated by means of hydro-geochemical transport modelling.The investigated factors significantly (Į = 0.05) affected the retention of P in the filter materials showing that it is important to consider those factors when designing laboratory filter experiments and full-scale filters. Using secondary wastewater as an influent instead of P solution decreased the P binding capacity of Filtralite P, probably due to organic compounds contained in the wastewater. Increasing influent P concentration decreased the number of bed volumes treated before breakthrough in Filtra P by 82%. The loading rate was shown to be an important design parameter. Increasing the loading rate, something commonly done in the laboratory to accelerate the testing, significantly increased the amount of washed-out particulate P in Filtra P and Filtralite P. However, the residence time was also shown to be important; it should be maximised in filter tests as far as practical constraints allow. Increasing the temperature from 4.3 to 16.5°C increased the P binding capacity in both Top16 and Polonite which was attributed to an enhanced precipitation of calcium phosphates. This indicates that results obtained from experimental filters at room temperature might overestimate filter performance in the field where the temperature can be lower. In addition, full-scale filters might function better in warm rather than cool climates. The results further showed that it is crucial to measure both the concentration of dissolved P and particulate P in the filter effluent, as P-containing particles were observed to escape from the experimental filters in this study. Hydroxylapatite was detected in the outflow hose of the Filtra P columns indicating that this mineral phase may form in the filters under certain conditions. The geochemical models, however, indicated that the only precipitated calcium phosphate compound was amorphous tricalcium phosphate.Two hydro-geochemical transport models were developed that satisfactorily described the experimentally derived P breakthrough curves and effluent pH of the filter columns with Filtralite P. The simulations suggested that calcium oxide, calcite and the calcium-silicate phase wollastonite supplied the Ca2+ and OH- ions required for the precipitation of phosphate.<br>Godkänd; 2014; 20140408 (ingher); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Inga Herrmann Ämne: VA-teknik/Sanitary Engineering Avhandling: Filter Beds for On-Site Wastewater Treatment Towards More Reliable Estimations of Phosphorus Retention Opponent: Professor Petter Jenssen, Institutt for miljøvitenskap, Norwegian University of Life Sciences, Ås, Norge Ordförande: Professor Maria Viklander, Avd för arkitektur och vatten, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Tid: Fredag den 13 juni 2014, kl 10.00 Plats: F1031, Luleå tekniska universitet
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Melcher, Anthony A. "Estimating Suspended Solids and Phosphorus Loading in Urban Stormwater Systems Using High-Frequency, Continuous Data." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7455.
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The introduction of pavement, buildings, and other impervious surfaces to urban landscapes greatly influences the quantity and quality of urban stormwater runoff. In this study, we designed and implemented modern stormwater monitoring technologies to establish a “smart” stormwater sensor network within the Northwest Field Canal (NWFC), an urban water conveyance located in Logan, Utah, USA. This network was designed to collect flow and water quality data at high frequencies and simultaneously at multiple locations. The observatory’s innovative method of inter-site communication and changing sampling frequencies during storm events was able to capture short duration events at the upstream and downstream ends of the NWFC and at multiple outfalls in the canal simultaneously without human intervention. We then investigated statistical regression models between turbidity and TSS so as to predict TSS at high frequencies. Finally, the addition of the high-frequency discharge data in the calibration procedure for a stormwater simulation model developed using the Environmental Protection Agency’s Stormwater Management Model did little to improve model performance at the downstream end of the canal, but did provide important insight into the overall contribution of discharge from individual stormwater outfalls to the NWFC. The results of this study inform water professionals on how to build and operate automated monitoring systems and how to create high-frequency estimates of TSS and TP loads in urban water systems.
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Manoharan, Ramanathan. "Readily biodegradable COD as an indicative parameter in estimating the efficacy of sewage for biological excess phosphorus removal." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/29242.
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The objectives of this research were to develop a reliable measurement technique to quantify the readily biodegradable substrates present in a sewage and to investigate their role in biological excess phosphorus removal, under acclimated conditions for each substrate added, leading to the characterization of a given sewage with respect to its natural efficacy in the biological excess phosphorus removal process.
The experimental work during this study involved two laboratory scale systems in which one was used to quantify the readily biodegradable substrates in the feed while the other was used as a biological excess phosphorus removal system. The readily biodegradable content of the feed was changed using different dosages of sodium acetate, sodium propionate, sodium butyrate and glucose. The effects of these compounds (both as specific substrates and as general readily biodegradable substrates) on the various elements of the biological excess phosphorus removal mechanism (such as anaerobic phosphorus release, aerobic phosphorus uptake, overall phosphorus removal, anaerobic carbon storage and aerobic carbon consumption) were investigated.
Results of this study showed that almost all the different elements of the biological excess phosphorus removal process compared very well among the different substrates used when the readily biodegradable substrates (quantified as readily biodegradable COD) was used as the unit of measurement. Also, the overall phosphorus removal efficiency improved with increasing amounts of readily biodegradable substrates entering the system.
A direct relationship existed between the phosphorus release in the anaerobic zone and the phosphorus uptake in the aerobic zone, according to
P uptake (mg/L) = 1.21 + 1.701 x P release (mg/L) with the constant of correlation being 0.985.
The results of this study also showed the importance of carbon storage. A definite link existed between the carbon storage (as PHB or PHV) and phosphorus release under the anaerobic conditions, and between the carbon consumption and phosphorus uptake under aerobic conditions. However, during the glucose addition trial, a second carbon storage compound (glycogen) was found to be stored under aerobic conditions and consumed under anaerobic conditions. An excellent linear relationship existed between the PHB synthesis and glycogen consumption, with the estimated mean value for the increase in the amount of PHB per unit of glycogen consumed being approximately 0.41, on a weight basis.
In terms of specific substrates, for the same dosage as COD, their effectiveness in biological excess phosphorus removal had the following decreasing order: acetate > propionate > butyrate > glucose
It was noticed during the study that whenever there was a reduction in the dosage of the added simple carbon substrates, the steady-state biological excess phosphorus removal continued for a period of upto 5 days at the same higher level before decreasing to the new lower level, reflecting the reduced substrate dosage. But, as a corollary, when the substrate dosage was increased, the excess phosphorus removal increased immediately without the presence of any significant lag period.<br>Applied Science, Faculty of<br>Civil Engineering, Department of<br>Graduate
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Grizzetti, Bruna. "Modélisation du devenir de l'azote et du phosphore d'origine ponctuelle et diffuse à l'échelle européenne." Paris 6, 2006. http://www.theses.fr/2006PA066041.
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Chu, Yin. "Flux de polluants en crue sur des petits bassins versants côtiers méditerranéens : sources, estimation et modélisation." Montpellier 2, 2006. http://www.theses.fr/2006MON20015.
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Ebadi, Nasim. "Estimating Costs of Reducing Environmental Emissions From a Dairy Farm: Multi-objective epsilon-constraint Optimization Versus Single Objective Constrained Optimization." Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/99304.
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Agricultural production is an important source of environmental emissions. While water quality concerns related to animal agriculture have been studied extensively, air quality issues have become an increasing concern. Due to the transfer of nutrients between air, water, and soil, emissions to air can harm water quality. We conduct a multi-objective optimization analysis for a representative dairy farm with two different approaches: nonlinear programming (NLP) and ϵ-constraint optimization to evaluate trade-offs among reduction of multiple pollutants including nitrogen (N), phosphorus (P), greenhouse gas (GHG), and ammonia. We evaluated twenty-six different scenar- ios in which we define incremental reductions of N, P, ammonia, and GHG from five to 25% relative to a baseline scenario. The farm entails crop production, livestock production (dairy and broiler), and manure management activities. Results from NLP optimization indicate that reducing P and ammonia emissions is relatively more expen- sive than N and GHG. This result is also confirmed by the ϵ-constraint optimization. However, the latter approach provides limited evidence of trade-offs among reduction of farm pollutants and net returns, while the former approach includes different re- duction scenarios that make trade-offs more evident. Results from both approaches indicate changes in crop rotation and land retirement are the best strategies to reduce N and P emissions while cow diet changes involving less forage represents the best strategy to reduce ammonia and GHG emissions.<br>Master of Science<br>Human activities often damage and deplete the environment. For instance, nutrient pollution into air and water, which mostly comes from agricultural and industrial activ- ities, results in water quality degradation. Thus, mitigating the detrimental impacts of human activities is an important step toward environmental sustainability. Reducing environmental impacts of nutrient pollution from agriculture is a complicated problem, which needs a comprehensive understanding of types of pollution and their reduction strategies. Reduction strategies need to be both feasible and financially viable. Con- sequently, practices must be carefully selected to allow farmers to maximize their net return while reducing pollution levels to reach a satisfactory level. Thus, this paper conducts a study to evaluate the trade-offs associated with farm net return and re- ducing the most important pollutants generated by agricultural activities. The results of this study show that reducing N and GHG emissions from a representative dairy farm is less costly than reducing P and ammonia emissions, respectively. In addition, reducing one pollutant may result in reduction of other pollutants. In general, for N and P emissions reduction land retirement and varying crop rotations are the most effective strategies. However, for reducing ammonia and GHG emissions focusing on cow diet changes involving less forage is the most effective strategy.
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Spence, Victora. "Estimating groundwater discharge in the oligohaline ecotone of the Everglades using temperature as a tracer and variable-density groundwater models." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3361.
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Recent research suggests that brackish, marine-derived groundwater up-wells in the oligohaline ecotone of the coastal Everglades, bringing with it phosphorus to an otherwise phosphorus-poor environment. The purpose of this study is to estimate the rates and timing of the groundwater discharge by using variable-density groundwater models constructed, calibrated, and validated with field measurements of hydraulic head and surface and subsurface temperature. Modeled groundwater discharge rates ranged from 5.4E-04 mm/day in August to -1.3E-03 mm/day in June for Shark Slough and 4.8E-01 mm/day in June to -1.4E-01 mm/day in January for Taylor Slough, where positive values imply groundwater discharge and negative values imply groundwater recharge. These results indicate that groundwater discharge rates during the period of study were low and perhaps a negligible source of marine-derived phosphorous in the oligohaline ecotone of Shark Slough but much higher and perhaps significant source of marine-derived phosphorous in the oligohaline ecotone of Taylor Slough.
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Freitas, Rodolfo de. "Avaliação da concentração de elementos químicos essenciais na merenda escolar de crianças da cidade de Ribeirão Preto e estimativa de suas ingestões." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/60/60134/tde-26062013-090738/.
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Para uma alimentação saudável, os alimentos consumidos devem conter quantidades adequadas de vários nutrientes. Atualmente, devido às interferências humanas na produção e comercialização de alimentos, os consumidores são incapazes de precisar a composição química e podem não estar ingerindo a quantidade correta de nutrientes. Neste sentido, se faz necessário o monitoramento da composição química dos alimentos e a estimativa de ingestão diária (WHO, 2005b). Deste modo, o objetivo deste trabalho foi, determinar a concentração dos elementos químicos essenciais fósforo (P), zinco (Zn), cálcio (Ca), ferro (Fe), sódio (Na), potássio (K), manganês (Mn), cobalto (Co) e selênio (Se) e a estimativa de ingestão diária no almoço de crianças em idade escolar através dos alimentos fornecidos pela Prefeitura de Ribeirão Preto. A metodologia utilizada no trabalho foi de dupla dieta, no qual os alimentos analisados estão prontos para o consumo. As merendas foram fornecidas por duas escolas municipais (infantil e ensino fundamental) e a cozinha piloto e, foram coletadas durante todos os dias letivos dos meses de março, junho, agosto e novembro de 2011. Os alimentos coletados foram congelados e liofilizados para posterior análise. As análises foram feitas utilizando a espectrometria de massas com plasma acoplado (ICP-MS) com prévia digestão ácida das amostras em ácido nítrico (HNO3)/peróxido de hidrogênio (H2O2). Os alimentos foram avaliados nas categorias arroz, feijão, carnes e verduras/ legumes. A ingestão média de P, Zn, Ca, Fe, Na, K, Mn, Co e Se foi, respectivamente, de 219 mg, 2,3 mg, 67,9 mg, 2,1 mg, 0,39 g, 0,62 g, 0,5 mg, 2,7 ?g e 7,1 ?g na escola de ensino infantil e foi respectivamente de 310 mg, 3,3 mg, 89,7 mg, 2,9 mg, 0,52 g, 0,80 g, 0,68 mg, 3,7 ?g e 10,1 ?g na escola de ensino fundamental. Foi avaliada, ainda, a variação da concentração destes elementos entre os locais de coletas de amostras e entre os períodos de coleta. As carnes foram as amostras em que ocorreram maiores variações estatísticas (p<0.05) entre os elementos estudados, provavelmente devido a associação de verduras e legumes nessas preparações em uma das escolas. Na avaliação sazonal os legumes e verduras apresentaram maior variação estatística nas concentrações dos elementos no decorrer do ano de coleta.<br>For a healthy eating, foods eaten should contain adequate amounts of various nutrients. Currently, due to human interference in the production and marketing of foods, consumers are unable to specify the chemical composition and cannot be ingesting the correct amount of nutrients. In this sense, it is necessary to monitor the chemical composition of foods and estimated daily intake (WHO, 2005b). Thus, the objective of this study was to determine the concentration of the essential elements phosphorus (P), zinc (Zn), calcium (Ca), iron (Fe), sodium (Na), potassium (K), manganese (Mn), cobalt (Co) and selenium (Se) and the estimated daily intake at lunch to school children through food provided by the city hall of Ribeirão Preto. The methodology used in this study was double-diet, where the foods analyzed are ready for consumption. The meals provided by two local schools and the kitchen pilot were collected during all school days in March, June, August and November of 2011. The food collected was frozen and lyophilized for further analysis. The analyzes were performed using inductively coupled plasma mass spectrometry (ICP-MS) after the acid digestion with nitric acid (HNO3) and hydrogen peroxide (H2O2) of the samples. The foods were evaluated in the categories: rice, beans, meat and vegetables. The average intake of P, Zn, Ca, Fe, Na, K, Mn, Co e Se was respectively 219 mg, 2.3 mg, 67.9 mg, 2.1 mg, 0.39 g, 0.62 g, 0.5 mg, 2.7 ?g e 7.1 ?g in elementary school children and was respectively 310 mg, 3.3 mg, 89.7 mg, 2.9 mg, 0.52 g, 0.80 g, 0.68 mg, 3.7 ?g e 10.1 ?g in meddle school. Was also evaluated the variation of the concentration of these elements between the sample collection sites and between sampling periods. The meats were a category in which there were more cases of statistically significant differences (p <0.05) between the elements studied, due to association of vegetables in these preparations at one of the schools. In assessing the seasonal, the vegetables had higher statistical variation in the concentrations of the elements throughout the year collecting.
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Bouchkira, Ilias. "Modélisation thermodynamique des solutions d'acides sulfurique et phosphorique en présence du minerai de phosphate : applications à l'encrassement, à la cristallisation et à l'optimisation multicritère d'une unité industrielle de production d'acide phosphorique." Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0056.
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Ce travail de thèse traite du développement d’un modèle thermodynamique et de son exploitation dans la modélisation, la simulation et l’optimisation des procédés de fabrication d’acide phosphorique. Il est décrit par des équations de bilans de matière et de charge, des équations d’équilibres chimiques, et l’équation du modèle de Pitzer. Il met en jeu plusieurs paramètres inconnus à identifier à partir de mesures expérimentales issues d’une base de données construite dans ce travail. Elle contient des mesures de spéciation d’acides phosphorique et sulfurique, des mesures de solubilité de dix minéraux, et des mesures de l’activité de l’eau de huit systèmes binaires. Ces mesures sont effectuées dans des conditions de températures allant de 298K à 353K et des concentrations allant de 0 mol/kg d’eau à 20 mol/kg d’eau. Une méthode basée sur l'analyse de sensibilité globale des paramètres est ensuite développée et utilisée pour évaluer l'estimabilité des paramètres inconnus. Ceux qui sont estimables sont alors identifiés, et les valeurs de ceux qui ne le sont pas sont fixées à partir de la littérature ou de précédentes études. Des mesures expérimentales, différentes de celles qui ont servi pour l’identification des paramètres, sont réalisées pour valider le modèle. Le test statistique F de Fisher-Snedecor et le test de Kolmogorov-Smirnov sont notamment utilisés. Les résultats de ces tests confirment les qualités de prédiction du modèle. Ce dernier est d’abord exploité dans l’optimisation multicritère d’une unité industrielle de production d’acide phosphorique, notamment pour la minimisation des pertes chimiques en phosphate et l’amélioration du rendement de l’unité. Il est ensuite utilisé dans l’analyse des problèmes d’encrassement qui se produisent lors de la production d’acide phosphorique et altèrent les performances des différentes unités du procédé de fabrication. Il est enfin exploité dans la modélisation et la simulation de la cristallisation des sulfates de calcium lors de la production de l’acide phosphorique. Le modèle ainsi validé et déjà exploité peut désormais être utilisé comme outil prédictif pour la conception et le fonctionnement optimal des procédés de fabrication d’acide phosphorique existants, voire pour le développement de nouveaux procédés plus intégrés et plus performants<br>This PhD work deals with the development of a thermodynamic model and its use in the modeling, simulation and optimization of phosphoric acid manufacturing processes. It consists of mass and charge balance equations, chemical equilibrium equations, and Pitzer’s model equation. The model involves several unknown parameters to be identified from experimental measurements available in a database developed in this work. It contains data on speciation of phosphoric and sulfuric acids, on solubility of ten minerals, and on water activity of eight binary systems. The measurements are performed under temperature conditions ranging from 298K to 353K and concentrations ranging from 0 mol/kg water to 20 mol/kg water. A global sensitivity based estimability analysis is then developed and used to evaluate the estimability of the unknown parameters from the available data. The estimable parameters are then identified, and the values of the non-estimable ones are taken from the literature or from previous studies. Additional experimental measurements, different from those used for the identification of parameters, are carried out to validate the model. The Fisher-Snedecor statistical test and the Kolmogorov-Smirnov test are particularly used. The results of the tests confirmed the quality of the model predictions. The validated model is first exploited in the multi-objective optimization of an industrial unit of phosphoric acid production, in particular to minimize the chemical losses of phosphate and to improve of the performance of the unit. It is then used to investigate the fouling problems that occur during the production of phosphoric acid and alter the performance of different units of the manufacturing process. Finally, the model is exploited in the modeling and simulation of the crystallization of calcium sulfates during the production of phosphoric acid. The model thus validated and already exploited can now be used as a predictive tool for the design and optimal operation of existing phosphoric acid manufacturing processes, or even for the development of new processes which are more integrated and more efficient
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Liu, Jih-Hung, and 劉紀宏. "Estimation of Phosphorus Loading in Rivers during High Flow Periods." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/87044283958751254440.
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博士<br>國立臺灣大學<br>土木工程學研究所<br>101<br>The reservoir in Taiwan almost subjected to the problem of eutrophication because of the surplus of nutrient result in the uncontrollable growth of algae. It is the most important topic to control the loading of phosphorus, in order to retain the good water quality of reservoir. Numerous agricultural activities, especially the production of tea or fruit in riparian areas, are conducted in watersheds in the upstream of reservoir. Nutrients from such activities, including phosphorus, are typically flushed into rivers during high flow period, when over 70 to 90 % of the yearly total amount of phosphorous enters reservoirs. Excessive or enhanced soil erosion from rainstorms can dramatically increase the river sediment load and the amount of particulate phosphorus flushed into rivers, at this time, the particulate phosphorus is the dominant form of phosphorus.
The study area Da-Lin bridge is located at the Daiyujay Creek watershed, which feeding the Feitsui Reservoir in Taiwan. First, the kinetic of adsorption/ desorption is found that after the water samples preserved over 16 hours the adsorption and desorption of the system approached equilibrium. During the high flow rate periods the Langmuir isotherm performed the best results of the others in the specific adsorption of phosphorus, furthermore, the amounts of TP transported through the river cross section during the June 9 rainstorm and Typhoon Bilis during duration T were accounted for roughly 0.7% and 28.8% of total TP loading during 2006, respectively. It shows that during the high flow rate periods which contributed the most amount of TP loading in a year. During high flow rates periods, the sampling data the of the river always regarded as the average concentration of the river section, which must be confirm first that the nutrient concentration is completely mixed at the sampling section or the estimation of the method may make some error.
Besides, river section are classified into several subsections during typhoon Saomai and typhoon Shanshan and the sampling and simulation are excuting by each subsection to identified a more efficiency method for more representative data. The Chiu’s sediment concentration distribution formula performs the suspended solid concentration well. As mention to the dissolved phosphorus, the method is developed by the diffusion theory and then dimensionless concentration profile formula is obtained. According to the result, assume that the major source of the nutrient occurred at the depth of the river with the same opportunities. The results show that as the average concentration could easily pump at the depth between 0.4-0.6D. In addition, as mention to the particulate phosphorus concentration profile, the results found that the most part of the suspended solid could classified as silt or clay, which used to adsorbed more particulate phosphorus than any others. The specific adsorption (=X/m) ranges of water samples in the typhoon Saomai and Shanshan are observed as 79-3,065 mg P/kg SS and 67-13,329 mg P/kg SS, respectively, which almost at the state of desorption. The usage of relation between basic concentration with adsorption coefficients and , whicn simplified the amount of sampling. So that the cost of sampling should be save and further makes the sampling of phosphorus becomes more efficiency and economic. To summarized the results of the research, which could found out the effect of management of land use in watershed by estimation of phosphorus loading during high flow periods and could also used as the references for the management of land use in watershed in future.
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Kraft, Clifford. "Estimation of phosphorus cycling by fish using a bioenergetics modeling approach." 1991. http://catalog.hathitrust.org/api/volumes/oclc/24417125.html.
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Thesis (Ph. D.)--University of Wisconsin--Madison, 1991.<br>Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
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Makhafola, Makhapa Abia. "Estimation of selected nitrogen compounds, nickel and phosphates in foodstuffs by continuous flow systems." Thesis, 2001. http://hdl.handle.net/2263/30549.
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Flow injection analysis offers distinct advantages in reproducibility, flexibility, sample throughput and cost performance. Since it was introduced in 1975, there are more than 10 000 publications to date. The present study focuses on the development of process analysers for the determination of nitrogen compounds (namely, nitrate, nitrite and protein), nickel, and phosphate in various combination in samples originating from various fields, such as foodstuffs, water, and fertilisers. Nitrite is potentially unstable; it decomposes with time under acidic medium with an increase in decomposition rate as the concentration of acid increases. Raman spectroscopy was employed as a means of determining the rate of decomposition of nitrite in solutions at various pH values. A simple method for the determination of nitrite in foodstuffs by flow injection analysis (FIA) is described. The foodstuffs containing nitrite are digested in a microwave oven and then treated with 1 moℓ/Q NH4CI solution at pH 9. The simultaneous determination of nitrate and nitrite in foodstuffs and water was also studied. Cadmium (coarse powder) was used to reduce nitrate to nitrite. The effect of pH, length of reductor column, and various types of cadmium reductor on the yield of nitrite are investigated. The flow injection method was developed for the spectrophotometric determination of nickel in cured meat. Dimethylglyoxime (DMG) in acetate buffer at pH 6.4 nickel forms a red complex which is measured at 475 nm. The effects of chemical and physical parameters in flow injection analysis were studied. A new bienzymatic amperometric sensor is proposed for the assay of proteins in milk. The sensor is based on two enzymes, namely, carboxypeptidases A and L-amino acid oxidase. The use of flow injection analysis and Raman spectroscopy for the determination of phosphate in foodstuffs and fertilisers, is also compared in this study.<br>Thesis (PhD (Chemistry))--University of Pretoria, 2007.<br>Chemistry<br>unrestricted
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Wang, Nai-Hui, and 王迺卉. "Preliminary estimation of total phosphorus in Pei-Shih River basin-Using Gin-Gua-Liao creek and Dai-Yu-Jue creek as example." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/20249128866802154717.
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Huang, Cheng-Lung, and 黃政龍. "The Method for Estimating Pollutant Phosphorus Loads in streams during rainstorms." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/44122989737620496279.
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Adams, Geoffrey. "Development of a simple hydrological modelling methodology for estimating phosphorus generation from rural land." Phd thesis, 2010. http://hdl.handle.net/1885/150832.
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Lin, Wang-Long, and 林文隆. "Development of an Internal Phosphorous Loading Estimating Procedure for a Lake or Reservoir." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/79009053290946274275.
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碩士<br>國立交通大學<br>環境工程研究所<br>82<br>Pollution load generated internally from a reservoir itself was
rarely studied in Taiwan and the amount of such load was
generally estimated on the basis of overall mass balance and
its spatial distribution was generally assumed to be uniform.
Such a rough estimation and assumption may not be appropriate
for a detail pollution control plan. This research was
therefore initiated to explore an appropriate phosphorous
internal loading estimation procedure for providing reliable
estimation and spatial distribution. The developed procedure
includes data colluction and processing, sampling equipment
selection and planning, modeling segmentation, sampling and
laboratory analysis for parameters including phsophorous
release rate in different water body segment and time interval,
the use of WASP5 model developed by U.S. EPA for water quality
simulation, external loading simulation and estimation using
AGNPS, and internal loading calibration and verification. The
case study for Po-San off-channel reservoir was implemented to
demonstrate the utilization of the proposed procedure for a
90 day period. Significant seasonal variation of phosphorous
release and difference between the results obtained from mass
balance method and the proposed procedure were observed. The
procedure is believed to be able to improve internal loading
estimation for the case study area and is expected to be
suitable also for other reservoirs in this country.
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XU, XHI-LIN, and 徐仕林. "Studies on the strategy of estimating lime reguirement and the effects of liming on phosphorus availability of strongly acid soils." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/33684760734659186976.
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El-Rifai, Hasan M. "Assessment of the utility of chemical pretreatments for estimating carbon and phosphorus sequestration in soils by 13C and 31P NMR spectrscopy [sic]." 2007. http://etd.lib.fsu.edu/theses/available/etd-07052007-210258.
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Thesis (Ph. D.)--Florida State University, 2007.<br>Advisor: William T. Cooper, Florida State University, College of Arts of Sciences, Dept. of Chemistry and Biochemistry. Title and description from dissertation home page (viewed Sept. 17, 2007). Document formatted into pages; contains xiv, 100 pages. Includes bibliographical references.