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The Radiochemistry of Selenium

Description: A review of the nuclear and chemical features of selenium, a discussion of problems of sample dissolution and counting techniques, and a collection of radiochemical procedures for the element as found in the literature are presented. (94 references) (M.C.G.)
Date: April 1961
Creator: Leddicotte, G. W.
Partner: UNT Libraries Government Documents Department

Selenium Poisoning of Wildlife and Western Agriculture: Cause and Effect

Description: This project examined the hypothesis that selenium contamination is not the principal cause of the decline of endemic fish species in the Upper Colorado Basin. Activities employed to test this hypothesis included a reconnaissance of locations altered by recent road construction, a re-interpretation of available literature regarding selenium toxicity, and the interpretation of unpublished data obtained from the Upper Colorado Basin Fish Recovery Program. The project demonstrates that most of the evidence implicating selenium is circumstantial.
Date: February 1, 2000
Creator: Korte, N.E.
Partner: UNT Libraries Government Documents Department

A Sprectrochemical Method for the Determination of Selenium

Description: A report about selenium which can be determined in pyrite, chalcocite, and marcasite by a spectrochemical method that is simple and rapid, and that requires no complicated arrangement of spectrographic equipment, or chemical pretreatment of samples.
Date: June 1957
Creator: Waring, Claude L.; Worthing, Helen & Hazel, Katherine V.
Partner: UNT Libraries Government Documents Department

Some Compounds of Plutonium With Metalloid Elements

Description: From abstract: "Experimental methods of the type employed for alloy preparation in metallurgical research have been used in attempts to prepare compounds of plutonium with four different metalloid elements: phosphorous, arsenic, selenium, and tellurium. By means of their X-ray diffraction patterns the existences of six previously unknown compounds have been established, but the composition and crystal structures of only three of the compounds have been determined."
Date: 1955
Creator: Gorum, Alvin Eugene
Partner: UNT Libraries Government Documents Department

FY08 Annual Report: Amorphous Semiconductors for Gamma Radiation Detection (ASGRAD)

Description: This is the annual report for an old project funded by NA22. The purpose of the project was to develop amorphous semiconductors for use as radiation detectors. The annual report contains information about the progress made in synthesizing, characterizing, and radiation response testing of these new materials.
Date: February 1, 2009
Creator: Johnson, Bradley R.; Riley, Brian J.; Crum, Jarrod V.; Ryan, Joseph V.; Sundaram, S. K.; McCloy, John S. et al.
Partner: UNT Libraries Government Documents Department

Effect of palladium dispersion on the capture of toxic components from fuel gas by palladium-alumina sorbents

Description: The dispersion and location of Pd in alumina-supported sorbents prepared by different methods was found to influence the performance of the sorbents in the removal of mercury, arsine, and hydrogen selenide from a simulated fuel gas. When Pd is well dispersed in the pores of the support, contact interaction with the support is maximized, Pd is less susceptible to poisoning by sulfur. and the sorbent has better long-term activity for adsorption of arsine and hydrogen selenide. but poorer adsorption capacity for Hg. As the contact interaction between Pd and the support is lessened the Pd becomes more susceptible to poisoning by sulfur. resulting in higher capacity for Hg, but poorer long-term performance for adsorption of arsenic and selenium.
Date: January 1, 2011
Creator: Baltrus, J.P.; Granite, E.J.; Rupp, E.C.; Stanko, D.C.; Howard, B. & Pennline, H.W.
Partner: UNT Libraries Government Documents Department

Pressure dependence of donor excitation spectra in AlSb

Description: We have investigated the behavior of ground to bound excited-state electronic transitions of Se and Te donors in AlSb as a function of hydrostatic pressure. Using broadband far-infrared Fourier transform spectroscopy, we observe qualitatively different behaviors of the electronic transition energies of the two donors. While the pressure derivative of the Te transition energy is small and constant, as might be expected for a shallow donor, the pressure derivatives of the Se transition energies are quadratic and large at low pressures, indicating that Se is actually a deep donor. In addition, at pressures between 30 and 50 kbar, we observe evidence of an anti-crossing between one of the selenium electronic transitions and a two-phonon mode.
Date: January 16, 2002
Creator: Hsu, L.; McCluskey, M.D. & Haller, E.E.
Partner: UNT Libraries Government Documents Department

The Association between Hantavirus Infection and Selenium Deficiency in Mainland China

Description: This article studies the role of selenium concentration in hemorrhagic fever with renal syndrome (HFRS) caused by hantaviruses, using a multidisciplinary approach combining ecological analysis with preliminary experimental data.
Date: January 20, 2015
Creator: Fang, Liqun; Goeijenbier, Marco; Zuo, Shu-Qing; Wang, Li-Ping; Liang, Song; Klein, Sabra L. et al.
Partner: UNT College of Arts and Sciences

Structure of bis(ethylenedithio)tetrathiafulvalenium dichlorocyanoselenate (2:1), (BEDT-TTF){sub 2}Cl{sub 2}SeCN

Description: The electron donor molecule BEDT-TTF has yielded approximately 50 superconductors to date. In addition, numerous other salts with a variety of electrical and magnetic properties have been discovered. Recently, the authors reported a semiconducting salt of BEDT-TTF with the novel T-shaped anion Br{sub 2}SeCN{sup {minus}2}. The crystallographic analysis of that salt revealed a near-centrosymmetric triclinic structure, except for the symmetry-breaking anion. On the basis of a Hamilton R-value test, the non-centrosymmetric space group P1 with ordered anions was preferred over centrosymmetric P{bar 1} with disordered anions. In this paper, the authors present the synthesis and crystal structure of the isostructural chlorine-analogue salt (BEDT-TTF){sub 2}Cl{sub 2}SeCN.
Date: December 31, 1995
Creator: Geiser, U.; Schlueter, J.A.; Dudek, J.D. & Williams, J.M.
Partner: UNT Libraries Government Documents Department

Development and evaluation of a hydride technique for As, Sb, and Se determinations by inductively coupled plasma-atomic emission spectroscopy

Description: A literature review of hydride techniques, experimental facilities, development and evaluation of a hydride technique, and interelement effects are covered. Suggestions for future work are given. (LK)
Date: January 1, 1977
Creator: Sloat, S. S.
Partner: UNT Libraries Government Documents Department

Selenium isotope geochemistry: A new approach to characterizing the environmental chemistry of selenium. Final report

Description: High levels of selenium in the environment will be a prominent water quality issue in the western United States for many years. Selenium accumulation is linked to increased rates of death and deformity in migratory birds, blind staggers in livestock, and selenosis in humans. In California, agricultural drain waters and oil refinery effluent contribute to high selenium content in the San Joaquin Valley and the San Francisco Bay. The importance of these industries to California`s economy precludes simple abatement, while the complexity of selenium cycling precludes simple remediation. The purpose of this project is to measure variations in the isotopic composition of selenium in water and soil samples caused by natural processes and to show, for the first time, the value of isotopic measurements in characterizing selenium pollution. The research seeks to identify sources of selenium pollution, determine processes in the selenium cycle, and support selenium remediation studies. The project required the successful integration of three components: (1) appropriate sampling a field setting showing Se enrichment and possibly isotopic fractionation, (2) analytical chemical methods for isolating and purifying the various species of Se in waters and sediment, and (3) mass spectroscopic instrumentation for high precision isotope abundance measurements.
Date: February 5, 1997
Creator: Volpe, A.M. & Esser, B.K.
Partner: UNT Libraries Government Documents Department

Comparative analysis of discharges into Lake Michigan, Phase I - Southern Lake Michigan.

Description: BP Products North America Inc. (BP) owns and operates a petroleum refinery located on approximately 1,700 acres in Whiting, East Chicago, and Hammond, Indiana, near the southern tip of Lake Michigan. BP provided funding to Purdue University-Calumet Water Institute (Purdue) and Argonne National Laboratory (Argonne) to conduct studies related to wastewater treatment and discharges. Purdue and Argonne are working jointly to identify and characterize technologies that BP could use to meet the previous discharge permit limits for total suspended solids (TSS) and ammonia after refinery modernization. In addition to the technology characterization work, Argonne conducted a separate project task, which is the subject of this report. In Phase I of a two-part study, Argonne estimated the current levels of discharge to southern Lake Michigan from significant point and nonpoint sources in Illinois, Indiana, and portions of Michigan. The study does not consider all of the chemicals that are discharged. Rather, it is narrowly focused on a selected group of pollutants, referred to as the 'target pollutants'. These include: TSS, ammonia, total and hexavalent chromium, mercury, vanadium, and selenium. In Phase II of the study, Argonne will expand the analysis to cover the entire Lake Michigan drainage basin.
Date: June 30, 2008
Creator: Veil, J. A.; Elcock, D.; Gasper, J. R. & Division, Environmental Science
Partner: UNT Libraries Government Documents Department

Novel Adsorbent-Reactants for Treatment of Ash and Scrubber Pond Effluents

Description: The overall goal of this project was to evaluate the ability of novel adsorbent/reactants to remove specific toxic target chemicals from ash and scrubber pond effluents while producing stable residuals for ultimate disposal. The target chemicals studied were arsenic (As(III) and As(V)), mercury (Hg(II)) and selenium (Se(IV) and Se(VI)). The adsorbent/reactants that were evaluated are iron sulfide (FeS) and pyrite (FeS{sub 2}). Procedures for measuring concentrations of target compounds and characterizing the surfaces of adsorbent-reactants were developed. Effects of contact time, pH (7, 8, 9, 10) and sulfate concentration (0, 1, 10 mM) on removal of all target compounds on both adsorbent-reactants were determined. Stability tests were conducted to evaluate the extent to which target compounds were released from the adsorbent-reactants when pH changed. Surface characterization was conducted with x-ray photoelectron spectroscopy (XPS) to identify reactions occurring on the surface between the target compounds and surface iron and sulfur. Results indicated that target compounds could be removed by FeS{sub 2} and FeS and that removal was affected by time, pH and surface reactions. Stability of residuals was generally good and appeared to be affected by the extent of surface reactions. Synthesized pyrite and mackinawite appear to have the required characteristics for removing the target compounds from wastewaters from ash ponds and scrubber ponds and producing stable residuals.
Date: January 31, 2010
Creator: Batchelor, Bill; Han, Dong Suk & Kim, Eun Jung
Partner: UNT Libraries Government Documents Department