Дисертації з теми "Lithologic sources of arsenic"
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Kitts, Heather Jane. "Estuaries as sources of methylated arsenic to the North Sea." Thesis, University of Plymouth, 1991. http://hdl.handle.net/10026.1/1867.
Повний текст джерелаVanDerwerker, Tiffany Jebson. "Evaluating Sources of Arsenic in Groundwater in Virginia using a Logistic Regression Model." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/77957.
Повний текст джерелаMaster of Science
Fosbury, DeEtta. "Identifying the influences of geothermal sources on shallow aquifer water quality." abstract and full text PDF (free order & download UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1446455.
Повний текст джерелаEdvardsson, Matilda. "Geochemical tracing of Arsenic sources in groundwater at the remediated Storliden mine, Skellefte district." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-82694.
Повний текст джерелаSveriges gruvindustri har förändrats i snabb takt, från ett flertal mindre gruvor till dagens läge med ett mindre antal större gruvor. Detta resulterar i förekomst av nedlagda gruvor runt om i Sverige. Efterbehandling av gruvor regleras genom lagstiftning, och kraven idag är betydligt högre än för bara något decennium sedan. Storlidengruvan var en zink- och koppargruva verksam mellan 2001–2008. Storliden ligger i Malå kommun och området ingår i Skelleftefältet, känt för sina sulfidmineraliseringar. Malmen bröts i en underjordsgruva med så kallad igensättningsbrytning, dvs. tomrum har succesivt fyllts ut med material under driften. Malmen beräknades vara förbrukad 2007, men när malmpriset ökade kunde gruvan leva vidare till 2008. Efterbehandlingen innebar att fylla igen gruvan med gråberg från Storliden men också gråberg från Bolidens gruvor Renström, Kedträsk och Kankberg. Dessutom användes anrikningssand, cement och slam från sedimentationsbassängerna för att fylla igen gruvan. Länshållning av gruvan upphörde och idag är gruvan vattenfylld. Höga arsenikhalter i vatten är ett hälsoproblem i delar av världen. Det kanske vanligaste exemplet är Bangladesh, där arsenik i grundvatten har orsakat hälsoproblem för miljontals människor. I Sverige är Skelleftefältet utmärkande för den höga arsenikhalten i berggrunden. Naturlig arsenikhalt i borrade brunnar har undersökts i flera studier som visar ett samband mellan arsenikhaltig berggrund och förhöjda halter i vatten. Examensarbetet har utförts tillsammans med konsultföretaget Golder Associates i Luleå. Golder har fått i uppdrag att utföra miljötekniska undersökningar i Storlidenområdet, bland annat ingick installation och provtagning av grundvattenrör. Denna provtagning skedde under perioden 2018–2020. I några av grundvattenrören påträffades förhöjda halter av arsenik. Detta examensarbete syftar till att utreda förekomsten av Arsenik i grundvattnet, undersöka vilka källor som kan vara orsaken till arsenikhalterna samt källornas förväntade betydelse. Detta har gjorts genom att utvärdera och tolka resultaten från provtagningarna samt användningen av Piper-diagram, geokemiska kvoter och geokemisk modellering i programmet PHREEQC. Resultaten indikerar att förekomst av arsenikkis som mineralisering i berggrunden är den mest troliga källan till de förhöjda halterna av arsenik i djupt grundvatten. Oxidationen av arsenikkis sker troligtvis främst av löst syre i grundvattnet. Vidare skiljer sig vattenkvalitén åt från olika djup och delar av området som provtagits, dvs. det verkar inte finnas någon omedelbar koppling mellan djupt grundvatten och vatten som kommer via rampen som leder till gruvan. Det är troligt att rester av anrikningssand på industriområdet orsakar lågt pH och metallutlakning lokalt. Höga arsenikhalter kan förekomma lokalt, vilket understryker vikten av att utföra provtagning av grundvatten som används för dricksvatten i områden där misstänkt eller konstaterade sulfidmineraliseringar förekommer, eftersom arsenik annars kan vara en mycket skadlig ”diffus” förorening. Vidare konstateras också samband mellan den tid som vatten är i kontakt med mineralisering och arsenikhalt. Högre halt HCO3- tenderar att korrelera med förhöjd arsenikhalt
Harvey, Abby (Abigail P. ). "Sources of arsenic and lead in drinking water of Eastport, Perry, and Pleasant Point, Maine." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/119317.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references (pages 58-61).
Lead and arsenic in drinking water are a health risk to communities throughout the world; lead can be a problem in houses with old piping systems with either lead piping or 50/50 lead solder, and groundwater in Maine contains high arsenic concentrations. This study sought to determine the prevalence and sources of arsenic and lead in the drinking water of Eastport, Perry, and Pleasant Point, Maine. Citizens of these towns submitted water samples from their homes, and arsenic and lead were measured in these samples. Each citizen submitted two samples: one where water stood in the pipes for a minimum of six hours, and another where the tap was flushed for 2+ minutes before sample collection. The primary water sources in the region were municipal water, from the Passamaquoddy Water District (PWD), and well water from private wells. Water samples were also collected from the source waters of the municipal water system, the Passamaquoddy Water District, and immediately following water treatment to determine sources of lead in the municipal system. Lead concentrations were found to be below the Environment Protection Agency (EPA) action level of 15ppb throughout the municipal system, and less than 1% of PWD samples exceeded the action level for lead in the standing samples. Overall, including houses with wells, 2% of houses exceeded the EPA action level in standing samples, and these houses are inferred to contain high lead levels in their piping. Arsenic levels in well water samples were found to exceed the EPA Guideline of 10[mu]g/L in 15% of samples, and did not depend on bedrock type, pH, or well depth, suggesting that bedrock heterogeneity and fracture geometry plays a large role in arsenic concentrations in this region.
by Abby Harvey.
M. Eng.
Magnone, Daniel. "Modelling the sources of organic material, processes and timescales leading to arsenic contamination of circum-Himalayan groundwaters." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/modelling-the-sources-of-organic-material-processes-and-timescales-leading-to-arsenic-contamination-of-circumhimalayan-groundwaters(852ae5a1-b09a-44fd-99b3-d8ae2dcc65c6).html.
Повний текст джерелаSelck, Brian John. "Natural and Anthropogenic Sources of Arsenic and Nitrate in a Semi-Arid Alluvial Basin; Goshen Valley, Utah." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/6533.
Повний текст джерелаDumaresq, Charles G. Carleton University Dissertation Earth Sciences. "The occurrence of arsenic and heavy metal contamination from natural and anthropogenic sources in the Cobalt Area of Ontario." Ottawa, 1993.
Знайти повний текст джерелаSiaka, Hermann Wilfried. "Compréhension des modes de désactivation de procédés catalytiques de traitement des NOx adaptés aux sources stationnaires." Thesis, Lille 1, 2020. http://www.theses.fr/2020LIL1R002.
Повний текст джерелаThe aim of this study is in connection to industrial problem which consists in implementing the best available technologies for the purification of fumes from industrial furnaces and particularly to check their lifetime due to deactivation phenomena. Nowadays, the catalytic technology is highly efficient to treat tail gas before rejection in the atmosphere. V2O5-WO3/TiO2 is recognized as benchmark catalyst and has been investigated in this study for the abatement of NOx. Poisoning effects induced by potassium and arsenic due to the use of biomass sources as fuel and more specifically in the fabrication process of glass were investigated.Potassium and arsenic poisoning have been simulated taking different K/V and As/V ratios corresponding to various time exposures of the catalysts in typical running conditions. The kinetic study allows the establishment of structure-reactivity relationships which can a priori predict the deactivation corresponding to a quasi-complete degradation of the catalysts for atomic ratios reaching 3. In these conditions, it was found that the selectivity is strongly altered mainly due the occurrence of undesired reactions: the ammonia oxidation to NO
Lucca, Enrico. "Geochemical Investigation of Arsenic in Drinking Water Sources in Proximity of Gold Mining Areas within the Lake Victoria Basin, in Northern Tanzania." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-224175.
Повний текст джерелаTillgången till rent, säkert vatten är en utmaning på landsbygdssamhällen i många utvecklingsländer. Åtgång på förorenat vatten riskerar människors hälsa och skadar social och ekonomisk utveckling. Naturlig förekomst av arsenik (As) i grundvatten är ett globalt miljöproblem, vilket utgör en allvarlig risk för människors hälsa på grund av metalloidens höga toxicitet. Med tanke på att arsenic sulfids mineraler är en viktigt del av guld insättning, har guldgruva aktiviteter anvisas som en orsak till att föroreningar av dränering och grundvatten i flera länder. Problemet med As i dricksvatten har uppmärksammats i Tanzania för några år sedan och det krävs ytterligare undersökning för att möjliggöra tidig upptäckt av skadliga exponeringar. Denna studie syftar till att bedöma förekomsten, källan och mobiliseringsmekanismerna för arsenik i vissa dricksvattenkällor i Lake Victoria Basin, i norra Tanzania. Landsbygdssamhällen som är kända för hantverksmässiga och storskaliga guldgruva arbeten var målet för den nuvarande studien. Femtiofyra vattenprover samlades från källvatten, borehålsvatten, floder och grundbrunn i Mara och Geita-regionen under oktober 2016. pH, redoxpotential (Eh), temperatur och elektrisk konduktivitet (EC) mättes i fält. Vattenprovernas koncentration av an- och katjoner, spårämnen (bl.a. arsenik), As(III) samt löst organiskt kol (DOC) analyserades i Sverige på Kungliga Tekniska Högskolan (KTH). Femtiotre procent av det provtagna vattnet överensstämmer inte med WHO:s rekommenderade gräns på 10 μg / l, vilket utgör en allvarlig hälsorisk fö vissa landsbygdssamhälen i Victoria-sjö. Den geografiska fördelningen av As i det undersökta området är högst heterogen och påverkas huvudsakligen av lokal geologi och närhet till gruvplatserna (ca <5km). Lägre As-nivår i borehål än i floder och grunda brunnar visar att föroreningar av dränering pågrund av gruvverksamhet och föeslår att djupt grundvatten (> 40m) i allmähet utgör en källa till säkrare dricksvatten. Däremot, visar denna studie att flera geokemiska processer kontrollerar förutbestämmelse och röligheten för As, nä det har blivit frisläppts ut i vattenmiljö. Stora skillnader mellan fält- och labbmäningar av As indikerar en stark partition av metalloid i partikelfraktionen. Som avslöjas av geokemisk modellering antas, samutfällning med järn / aluminiumhydroxider och adsorption på lermineraler vara de huvudsakliga sänkorna fö upplöst As. Dessutom antyder en bra matchning mellan toppar i As och upplösta organiska kolkoncentrationer att komplexbildning med humana och fulviska syror är ansvarig för föbättrad rölighet.
Ikehata, Mariko. "Evaluation of trace metal distributions (arsenic, cadmium, lead) and lead sources in sediments from a sound and an inlet on the west coast of Vancouver Island, British Columbia." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45731.
Повний текст джерелаErgene, Suzan Muge. "Lithologic heterogeneity of the Eagle Ford Formation, South Texas." Thesis, 2014. http://hdl.handle.net/2152/25752.
Повний текст джерелаtext
Weng, Tsung-Nan, and 翁宗男. "Isotopic evidence and simulation of nitrogen sources, transformation, and transport in arsenic-contaminated groundwater." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/q32rkb.
Повний текст джерела國立臺灣大學
生物環境系統工程學研究所
107
In this study, on the basis of physicochemical characteristics of groundwater and the nitrogen and oxygen isotope composition of NO3−, it was inferred that the main sources of NO3− in the proximal fan of the Choushui River alluvial fan are likely to be ammonium fertilizers, manure, and septic waste; that in the mid-fan and the distal fan, the possible sources are nitrate fertilizers and marine nitrate. In the proximal fan, the oxidative state obviously promotes microbial nitrification. High DO concentrations and relatively low values of δ18ONO3 in the deeper aquifer of the proximal fan may be attributed to unconfined granular nature and groundwater pumping by agricultural activities. In the mid-fan, NO3− assimilation is the dominant response to NO3− attenuation, and denitrification is insignificant; however, high concentrations of As, NH4+ and Fe and depletion of δ15NNO3 imply the occurrence of feammox process. By contrast, denitrification evidently occurs in the distal fan, through assimilation, mineralization, and dissimilatory NO3− reduction to NH4+, resulting in depletion of NO3− and increase in NH4+ in groundwater. Feammox in the mid-fan and denitrification in the distal fan may be the main processes leading to the release of As from As-bearing Fe oxyhydroxides into groundwater. The simulation result of nitrification shows that the nitrification and/or feammox mostly occur in the proximal fan and mid-fan, whereas they slightly occur in the distal fan. The concentrations of NO3− and NH4+ in the proximal fan evidently support the occurrence of NH4+ nitrification. The spatial concentration distribution of NO3− from the proximal fan to the distal fan indicates the gradual occurrence of NO3− denitrification and/or DNRA from upstream to downstream of the Choushui River alluvial fan. The mid-fan and the distal fan were assessed on the basis of the local DO and ORP values to be in relatively more reductive conditions, driving the occurrence of denitrification and/or DNRA. In the proximal fan, As3+ decreased and As5+ increased, and this valence transformation of As species and As concentration difference seem comprehensible. In the mid-fan and the distal fan, the reductive state was observed base on the DO and ORP data of the groundwater, and the circumstance of reduction from As5+ to As3+ was obvious. The discrepancy of δ15N in NO3− in groundwater was simulated on the basis of the influence of the reaction of NO3− denitrification. The values of δ15NNO3 increased in the groundwater of the mid-fan and the distal fan; in theory, the denitrification increases δ15N values of the residual NO3−. The 1-D transport simulation result suggested that NO3− assimilation occur from the mid-fan of the Choushui River Alluvial Fan to the distal fan, whereas NH4+ nitrification is observed at the beginning of the proximal fan. The concentration of As5+ increased at the beginning of the mid-fan, which may be caused by the reductive dissolution of As-bearing Fe oxyhydroxides and the desorption of adsorbed As. The concentration of As3+ increased obviously at the beginning of the distal fan, which may be related to the transformation of As5+ to As3+ in the reductive environment, and the continuous desorption of As from Fe oxyhydroxides simultaneously. Both the concentrations of Fe3+ and Fe2+ increased at the end of proximal, causing by the reductive dissolution of Fe oxyhydroxides. The transformation of Fe3+ to Fe2+ occurred soon when the groundwater reached the mid-fan. The increase in Fe2+ is not only related to the reductive environment, but also attributed to the reaction of feammox, which Fe oxyhydroxides react with NH4+ and produce Fe2+ in the groundwater.
Wrye, Lori Ann. "Distinguishing between natural and anthropogenic sources of arsenic in soils from the Giant mine, Northwest Territories and the North Brookfield mine, Nova Scotia." Thesis, 2008. http://hdl.handle.net/1974/1547.
Повний текст джерелаThesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2008-09-29 17:21:50.73
Chen, Sheng-Kuen, and 陳聖堃. "Using Lead Isotopic Ratios to Trace the Sources of Arsenic and Lead of Paddy Soils at Guandu, Beitou." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/83030501368118516781.
Повний текст джерела國立臺灣大學
生物環境系統工程學研究所
96
In Guandu Plain, 128 hectares of paddy soils with the high arsenic content, exceeding soil pollution control standards (over 60 mg kg-1), were determined due to the irrigation with the water mixed hot spring with arsenic in the early periods. The isotopic compositions of lead exhibits wide variations in natural and anthropogenic materials that often can be used as a diagnostic“signature.”Lead isotopic compositions, analyzed on multi-collector inductively coupled plasma mass spectroscopy was used to distinguish pollution sources. The results of cluster analysis clearly indicate that the paddy soils of Guandu Plain have been primarily influenced by the parent rock of Tatun Volcano Group because those were located within the basin of Huang Gang Creek and the soil of the polluted extremely polluted lead was from the long-term irrigated with the water mixed hot spring in the Thermal Valley. Furthermore, the anthropogenic pollution was also verified in the paddy soils with the exceptional lead content. The results suggest that lead isotope ratios can be used effectively to constrain the sources of lead in Guandu Plain, especially for natural versus anthropogenic influence can be identified.
Huang, Hsin-Jan, and 黃馨冉. "Relationship among Arsenic, Cadmium, Manganese, Mercury andLead of Maternal Blood, Cord Blood and Placenta, and TheirPotential Exposure Sources." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/40190048926064153196.
Повний текст джерела臺灣大學
職業醫學與工業衛生研究所
96
Abstract Pregnant women and fetuses are susceptible to environmental hazards. If women are exposed to heavy metals during pregnancy, their fetuses’ growth development could be adversely affected. Therefore, the aims of the present study were to find the relationship of arsenic, cadmium, manganese, mercury, and lead concentrations among maternal blood, cord blood and placenta, and to explore the potential environmental exposure sources of these five metals. Study subjects included 480 mother and infant pairs collected from three different level hospitals in Taipei area. Questionnaires were administered to get study subjects’ environmental exposure history before and during pregnancy. Biological samples, including maternal blood, cord blood, and placenta, were collected at delivery. Then ICP-MS was applied to analyze arsenic, cadmium, manganese, mercury and lead contents in maternal blood, cord blood, and placenta samples. Metal concentrations in maternal blood, cord blood, and placenta samples were as follows (GM (GSD)): 4.47 μg/L (1.66), 3.72 μg/L (1.55), 22.91 ng/g (1.62) for arsenic, 1.15 μg/L (2.04), 0.23 μg/L (3.55), 63.10 ng/g (1.48) for cadmium, 20.89 μg/L (1.62), 46.77 μg/L (1.38), 549.54 ng/g (1.23) for manganese, 5.25 μg/L (2.69), 11.48 μg/L (1.86), 213.80 ng/g (1.62) for mercury, and 14.13 μg/L (2.24), 11.48 μg/L (2.00), 66.07 ng/g (1.70) for lead, respectively. The correlations among the concentrations of the study metals were examined by Pearson’s correlation. It appeared that arsenic and lead concentrations, respectively, in maternal blood, cord blood, and placenta were significantly and positively correlated. Manganese and mercury concentrations, respectively, in cord blood and placenta were also significantly positively correlated, as well as the mercury concentrations in maternal blood and cord blood. A significant correlation of cadmium concentration was only shown between maternal blood and placenta samples. Because it was prohibited to use leaded gasoline, cord blood lead concentration was continuously decreasing. From 2002 to 2004, cord blood lead concentration was decreased by about 10 μg/L. Although maternal and cord blood mercury concentrations also decreased by 50% during the past years, they were still significantly higher than those of western countries. Multiple stepwise regression models were used to explore the factors affecting the maternal blood, cord blood and placental arsenic, cadmium, manganese, mercury, and lead concentrations. Results showed that study area was the major factor of maternal blood arsenic and mercury concentrations, and also affected maternal blood manganese and lead and cord blood cadmium and placental manganese and lead concentrations. Cord blood arsenic, manganese, mercury and lead and placental arsenic, cadmium and mercury concentrations were affected by those concentrations of maternal blood. In cord blood and placental lead concentrations, maternal blood lead concentration and study area had about the same influence of cord blood and placental lead concentrations. Cord blood lead concentration was getting close to the developed countries. However, mercury concentrations in maternal and cord blood were still high. To find out the exposure mechanism, a follow-up study may be needed to investigate the possible mercury exposure sources for the pregnant women in the future.
Liao, Chih-Wei, and 廖志偉. "A study of arsenic metabolism patterns in humans exposed from sources of Industry and undergrand water of I-lan." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/24880070039697922659.
Повний текст джерела高雄醫學大學
職業安全衛生研究所碩士班
92
The arsenic compounds were a ubiquitous element found in various sectors such as industry manufacturing process and related applications, however risk of health effects of arsenic compounds were an existing problem hard to ignore. There were many possible routes of arsenic exposure, the frequently mentioned were inhalation and ingestion. Different route of exposure can derive to different pattern of arsenic metabolism, while industrial exposure and environmental exposure from drinking water were anticipated with different results and safety. This research collected spot urine from people exposed through industrial and drinking water sources. The urine samples were analyzed with HPLC and HG-AAS for arsenic species, which were metabolized from exposed body into urine. Both stratified analysis and statistical methods were applied to differentiate arsenic metabolism patterns between people from industrial and drinking water exposures. The data have shown that the total amount of urinary arsenic metabolism on arsenite (As3+) were larger than arsenate(As5+) in industrial exposures while a reverse observation was made in drinking water exposures. A larger amount of dimethylarsinics acid(DMA) was found in both exposure sources than that of monomethylarsinics acid(MMA). For the metabolism pattern of arsenic species, the percentage of inorganic arsenic, the percentage of MMA, and the ratio of MMA to DMA, drinking-water exposure was larger than industrial exposure. However, the percentage of DMA was larger in industrial exposure than that of drinking-water exposure. The study has found that different routes of arsenic exposure resulted in different pattern of urinary arsenic metabolism patterns while the biohazard markers of inorganic arsenic were found to be different, which gives implications for different risk of adverse effects in the future. The previous studies on risk analysis of inorganic arsenic exposure were rarely taking metabolism patterns into accounts. The findings in this thesis deserve for further consideration in policy making of industrial safety and health. ability, so this research to establish the standard for industrial safety and health in further.
Ormachea, Muñoz Mauricio. "Hydrogeochemistry of Naturally Occurring Arsenic and Other Trace Elements in the Central Bolivian Altiplano : Sources, mobility and drinking water quality." Doctoral thesis, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-168190.
Повний текст джерелаQC 20150529