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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Origin of arsenic in the alluvial aquifer of the Region Lagunera, States of Coahuila and Durango, Mexico

Gutierrez-Ojeda, Carlos. January 1995 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources) - University of Arizona. / Includes bibliographical references (leaves 230-
22

Metabolism of inorganic arsenic and biomarkers of exposure /

Concha Quezada, Gabriela, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2001. / Härtill 5 uppsatser.
23

Chemistry of arsenic in soils of north-east New South Wales /

Smith, Euan. January 1998 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, Dept. of Soil Science, 1998. / Includes bibliographical references (leaves 137-151).
24

The use of slightly alkaline solvents in the separation of arsenic from antimony

Coon, Philip Leslie. January 1932 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1932. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
25

Arsenite phytochelatin complexes in plants : an analytical challenge /

Blümlein, Katharina. January 2008 (has links)
Thesis (Ph.D.)--Aberdeen University, 2008. / Title from web page (viewed on Apr. 14, 2009). With: Stability of arsenic peptides in plant extracts: off-line versus on-line parallel elemental and molecular mass spectrometric detection for liquid chromatographic separation / Katharina Bluemlein, Andrea Raab, Jörg Feldman. Anal Bioanal Chem. With: Advantages and limitations of a desolvation system coupled online to HPLC-ICPqMS/ES-MS for the quantative determination of sulphur and arsenic in arseno-peptide complexes / Katharina Bluemlein, Eva M. Krupp and Jörge Feldman. Journal of analytical atomic spectrometry, 2009: 24, 108-113. With: Can we trust mass spectrimetry for determination of arsenic peptides in plants: comparison of LC-ICP-MS and LC-ES-MS/ICP-MS waith XANES/EXAFS in analysis of Thunberfia alata / Katharine Bleumlein .. et al. Includes bibliographical references.
26

De complexiteit van het arseentrioxyde ...

Beljaars, Maxime Marie Henri Toussaint Eugéne. January 1900 (has links)
Proefschrift-Amsterdam.
27

The development of arsenic and its effect on plague in early modern Europe

Konkola, Kari. January 1981 (has links)
Thesis (M.A.)--University of Wisconsin--Madison, 1981. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
28

Arsenic geochemistry and its impact in public health: the Bangladesh case

Sánez, Juan 25 September 2017 (has links)
Considered the king of poisons, arsenic occurs naturally in the environment being present in air, soil, water and food. Its presence in drinking water is of global concern. Initial chronic exposure is manifested by skin lesions. Additionally, arsenic consumption impairs certain visceral organs: bladder, liver, prostate, etc. More over, arsenic is a recognized carcinogenic substance.When in Bangladesh started the program to lead safe drinking water in the 60’s, they never imagined the catastrophic consequences. Water wells were drilled in the whole country. The arsenic problem was recognized recently in the 90’s.  In order to understand the nature of arsenic  in the environment and how it could possibly reach groundwater in Bangladesh, this work explains some chemical characteristics of arsenic, the geological formation of the basin, and its mobility.The origin of arsenic contamination in the Bangladesh Delta is due to the geologic nature of the basin rather than the possibility of an arsenic rich mineral. The profile of sediments shows that the Delta is not homogeneous, but rather heterogeneous even in closer areas. The driving process for arsenic mobility is mainly the reduction by iron oxyhydroxides coupled with organic matter, including other factors such as particle size, depth, morphology, metal content, as well
29

Arsenic in Arizona: Assessing the Economic Cost and Hydrogeologic Feasibility of Nontreatment Options

Davis, Jacob January 2005 (has links)
The United States Environmental Protection Agency recently issued a new MaximumContaminant Level (MCL) for arsenic in drinking water. The new MCL lowers theacceptable level of arsenic in drinking water from 50 parts per billion to 10 parts perbillion. Treatment technologies for arsenic removal are expensive to operate.Nontreatment options pose an alternative to treatment. Nontreatment is allowed undergovernment regulation. However, such options are limited by local hydrogeologicconditions. Many areas in Arizona have favorable conditions. Estimates for the capitalcosts for several nontreatment options were collected through surveys. In a comparison ofthe capital costs of nontreatment options to treatment, nontreatment was less than half thecost of treatment. Operating costs for nontreatment are also expected to be several timessmaller than for treatment. A comparison using annualized costs shows that nontreatmentcosts less than one fifth of treatment.
30

The characterization, persistence, and bioaccessibility of roaster-derived arsenic in surface soils at Giant Mine, Yellowknife, NT

Bromstad, Mackenzie Jane 23 November 2011 (has links)
Approximately 20,000 tonnes of arsenic (As)-bearing emissions from roasting arsenopyrite ore were aerially released from 1949-1999 at Giant Mine, located outside Yellowknife, NT. As part of the process used to free refractory gold (Au) from arsenopyrite (FeAsS), roasting created As-bearing roaster off-gases that condensed into As2O3, one of the most toxic As compounds to humans. Roaster emissions also contained some As-bearing iron (Fe)- oxides. Arsenic emission controls were first implemented in 1951, and by the time the emission control process was completely refined in 1963, 86% of the total aerial As emissions at Giant had been released into the surrounding area. The continued presence of roaster-derived As2O3 in surface soils at Giant has been previously documented despite its theoretical instability in oxidizing surface environments. Wrye (2008) found As concentrations in roaster-affected soils occurring on rock outcrop (covering ~30% of the Giant property) greater than in many other surface soils; most outcrop soils were not considered when delineating areas of contaminated material for future removal in the Giant Mine Remediation Plan (currently undergoing environmental assessment). To investigate roaster-derived As persistence, outcrop soils and soil pore waters were analyzed. Comparing proportions of As, Sb, and Au concentrations in soil samples and historic As2O3-rich dust captured by emission controls show that most of the roaster-derived As in soils at Giant was likely deposited before 1964. Thin section examination has shown that while the vast majority of discrete As hosts in soils are As2O3, textural relationships and certain secondary As hosts in soils indicate that As2O3 is not static in surface soils and could be transforming over time, albeit very slowly. Bulk chemical relationships among As, antimony (Sb), and carbon support this. Topographic restriction by rock outcrops and dry, cold climate probably play a large role in elevated As concentrations and As2O3 persistence in outcrop soils. In light of possible future human exposure, As bioaccessibility from three adjacent samples was determined for synthetic human gastric (34%) and lung (18%) fluids. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2011-11-22 16:16:24.721

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