Дисертації з теми "Metal selenide"
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Kamada, Rui. "Copper(indium,gallium)selenide film formation from selenization of mixed metal/metal-selenide precursors." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 226 p, 2009. http://proquest.umi.com/pqdweb?did=1654501631&sid=4&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Повний текст джерелаBoscher, Nicolas D. "Atmospheric pressure chemical vapour deposition of transition metal selenide thin films." Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1444549/.
Повний текст джерелаKim, Changsu. "Optical, laser spectroscopic, and electrical characterization of transition metal doped ZnSe and ZnS nano- and microcrystals." Birmingham, Ala. : University of Alabama at Birmingham, 2009. https://www.mhsl.uab.edu/dt/2009r/kim.pdf.
Повний текст джерелаTitle from PDF title page (viewed Feb. 3, 2010). Additional advisors: Renato Camata, Derrick Dean, Chris M. Lawson, Andrei Stanishevsky, Sergey Vyazovkin. Includes bibliographical references (p. 133-140).
Gatuna, Ngigi wa. "Intrinsic vacancy chalcogenides as dilute magnetic semiconductors : theoretical investigation of transition-metal doped gallium selenide /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/10595.
Повний текст джерелаLuo, Ming. "Transition-metal ions in II-VI semiconductors ZnSe and ZnTe /." Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4630.
Повний текст джерелаTitle from document title page. Document formatted into pages; contains xiv, 141 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 135-141).
Cooke, Sharon A. "Alternative chalcogen sources for the growth of cadmium sulfide and cadmium selenide by metal organic chemical vapour deposition." Thesis, University of Reading, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284186.
Повний текст джерелаSheridan, Liam A. "Alternative cadmium source precursors for the growth of cadmium sulphide and cadmium selenide by metal-organic chemical vapour deposition." Thesis, University of Reading, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339511.
Повний текст джерелаBeer, Michael P. "A study of volatile precursors for the growth of cadmium sulphide and cadmium selenide by Metal Organic Vapour Deposition." Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303986.
Повний текст джерелаAshraf, Shakeel. "Evolution of IR Absorber for Integration in an IR Sensitive CO2 Detector." Thesis, Mittuniversitetet, Institutionen för informationsteknologi och medier, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-14088.
Повний текст джерелаKling, Willig Fabian. "Selenium Recovery in Precious Metal Technology." Thesis, Umeå universitet, Kemiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-86735.
Повний текст джерелаWalton, Richard I. "The characterisation and structure of amorphous and poorly crystalline transition-metal chalcogenides." Thesis, University of Reading, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388467.
Повний текст джерелаMorris, R. E. "Synthesis and characterization of metal phosphites and selenites." Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314881.
Повний текст джерелаChiu, Winnie Wai Hang. "Metal complexes with sulfur and selenium donor ligands /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202009%20CHIU.
Повний текст джерелаd'Arbeloff-Wilson, Sarah. "Reactions of the phosphaalkyne, PCBu't with metal sulphides, selenides and tellurides." Thesis, University of Sussex, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324201.
Повний текст джерелаVergnaud, Céline. "Optimisation de la croissance de MoSe2 - WSe2 par épitaxie de Van der Waals pour la valleytronique." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALY038.
Повний текст джерелаThe purpose of this thesis is to optimize growth by molecular beam epitaxy in the van der Waals regime of two-dimensional (2D) semiconductor layers of transition metal diselenides (MoSe2, WSe2) for magneto-optical and electric studies. This optimization involves improving the crystallographic quality of the layers over large areas by adjusting the growth parameters (temperature and flux). In particular, the control of the surface state of the substrate is decisive on the growth mechanisms of these layers. The development of these low-dimensional materials required the use of advanced characterization techniques (Grazing incidence X-ray diffraction, High Resolved Transmission Electronic Microscopy, ect). In this thesis, we focused on two specific substrates : silicon oxide and mica. They both have the particularity of being insulating and inert from an electronic point of view, which is essential to probe the optical and electrical intrinsic properties of 2D layers. Finally, we developed electrical doping (p doping) for microelectronics and magnetic (Mn doping) for valleytronics
Al-Attar, A. F. "Selenium and trace metals as pollutants." Thesis, University of Bristol, 1987. http://hdl.handle.net/1983/1858b91b-362e-422f-b91c-84aa44e23e90.
Повний текст джерелаWeber, Frank. "Präparative Studien in den Mehrstoffsystemen Selten-Erd-Metall - Selen bzw. - Tellur und Sauerstoff." [S.l.] : Universität Stuttgart , Fakultät Chemie, 1999. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB8287476.
Повний текст джерелаLing, Jie Albrecht-Schmitt Thomas E. "Hydrothermal syntheses, structures, and properties of new iodate and selenite compounds of transition metals, lanthanides, and actinides." Auburn, Ala, 2007. http://repo.lib.auburn.edu/2007%20Fall%20Dissertations/LING_JIE_49.pdf.
Повний текст джерелаLachaîne, Martin. "Monte Carlo optimization of a metal/amorphous-selenium portal imager." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ37138.pdf.
Повний текст джерелаGreenfield, Joshua Thomas. "Synthesis and Characterization of Low-Dimensional Iron Selenides and Transition Metal Formate-Chlorides." Thesis, University of California, Davis, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10682102.
Повний текст джерелаSeveral solvothermal synthetic methods have been developed to produce novel low-dimensional magnetic materials and determine their structure-properties relationships. Two main classes of compounds were investigated, including iron selenides and transition metal formate-chlorides.
Chapter 2 details the development of the first solution-based synthetic route to superconducting iron (II) selenide. Samples were found to retain superconducting properties only when air and water were rigorously excluded from the synthesis.
Chapter 3 presents the synthesis, structure, and magnetic properties of two new mixed-valence compounds with infinite ∞1(FeSe 2) tetrahedral chains separated by Fe-amine complexes. The use of different Fe-amine complexes allows for tuning of the magnetic properties without changing the general structural motif.
Chapters 4 and 5 report the first members of the transition metal chloride-formate family of compounds, which contain linear zig-zag chains of octahedrally coordinated metal atoms linked by μ2-Cl and syn-syn formate bridges. These compounds order antiferromagnetically and exhibit metamagnetic transitions.
Chapter 6 describes a related set of transition metal formate-chloride compounds that are comprised of helical chains of edge-sharing M2+ -centered octahedra. These compounds undergo 3D ferrimagnetic ordering at low temperature, and are rare examples of homospin topological ferrimagnets.
Thiagarajan, Suraj Joottu. "Thermoelectric properties of rare-earth lead selenide alloys and lead chalcogenide nanocomposites." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1196263620.
Повний текст джерелаGarland, Jacqueline M. "Studies in phosphorus-selenium chemistry." Thesis, University of St Andrews, 2013. http://hdl.handle.net/10023/3688.
Повний текст джерелаChan, Alan Chin Luen. "Fabrication and measurements on metal-semiconductor diodes." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63966.
Повний текст джерелаSadler, Mark. "Main group selenium chemistry and a series of hydrophobic bispidone-transition metal complexes." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515118.
Повний текст джерелаSu, Sheng-Han [Verfasser]. "Investigations into Rare-Earth Metal(III) Oxoselenates(IV) and Ultra-Thin Layered Selenides / Sheng-Han Su." München : Verlag Dr. Hut, 2018. http://d-nb.info/1164293583/34.
Повний текст джерелаLima, Leonardo Warzea [UNESP]. "Selenium and sulfur: mitigation in plant stresses." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/138897.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
As plantas não possuem mecanismos de defesa específicos para combater a diversidade de estresses abióticos e poluentes do ambiente, e sua sobrevivência depende da flexibilidade e adaptação dos seus próprios mecanismos de defesa naturais. Além disso, a manutenção da homeostase celular depende de vários mecanismos interligados e complexos, enquanto o sistema de defesa celular não segue um padrão específico de ação e pode ainda variar devido a vários fatores tais como a espécie do vegetal, o tempo de exposição ao estresse, o estágio de desenvolvimento da planta e também nos diferentes órgãos e tecidos analisados. Com base nessas considerações, esta dissertação teve como objetivo destacar e investigar o papel do Enxofre (S) e do Selênio (Se) contra diferentes estresses nas plantas, através das respostas enzimáticas, não enzimáticas e também outros mecanismos de defesa relacionados. No primeiro capítulo, o autor caracteriza os mecanismos bioquímicos gerais da defesa celular antioxidante, especificamente a formação das espécies reativas de oxigênio (EROs) e suas singularidades químicas e o estresse oxidativo induzido, o sistema de defesa antioxidante enzimático, especificamente as enzimas Superóxido Dismutase (SOD) e a Catalase (CAT), os mecanismos não-enzimáticas contra o estresse, incluindo o ciclo Aascorbato-Glutationa, a GSH (glutationa reduzida), as fitoquelatinas e também a formação de prolina. O estado nutricional da planta durante o estresse é crucial a fim de manter uma resposta de defesa adequada. Em vista disso, o capítulo dois apresenta uma revisão sobre a participação de Enxofre (S) na defesa contra o estresse. Este nutriente tem um papel importante em processos fundamentais, tais como o transporte de elétrons, estrutura, regulação, produção de oxigênio fotossintético, resistência a estresses abióticos e bióticos e no metabolismo secundário. Além disso, alguns elementos químicos são considerados benéficos para as plantas, no qual o Selênio (Se) é o mais relevante. No capítulo três, o autor descreve o papel do Se na amenização do estresse induzido pela contaminação por metais pesados, suas poderosas características antioxidantes, a melhoria da atividade de enzimas antioxidantes e também dos mecanismos globais de defesa. O capítulo quatro consiste em um projeto científico conduzido pelo autor. O objetivo deste estudo foi investigar se o Selênio, sob a forma de selenito (Na2SeO3), é capaz de evitar a absorção, translocação e concentração de cádmio (CdCl2), em diferentes tecidos no tomate, indicando os possíveis mecanismos para amenizar o estresse, bem como também analisar o estado geral dos frutos através das análises nutricionais, peso seco, pigmentos e concentração de Prolina livre. Os resultados demonstram que efeito atenuante do Se em tomateiro submetido ao Cd poderia estar relacionado com a restrição da absorção e translocação de Cd2+, aumentando a concentração de micronutrientes nos frutos e, finalmente, aumentando a concentração de prolina livre nos frutos.
Plants do not have specific defense mechanisms to counteract the diverse range of abiotic stresses and pollutants into the environment, and its survival depends on the flexibility and adaptability of its own natural defense mechanisms. Furthermore, the maintenance of cellular homeostasis depends on several interlinked and complex mechanisms, while the cellular defense system does not follow a specific pattern of action and may differ due to various factors such as plant species, exposure time to the stress, plant developmental stage, different organs and tissues analyzed. In the light of these considerations, this dissertation aimed to highlight and investigate the role of Sulfur and Selenium against different plant stresses, through the enzymatic and non-enzymatic plant responses and other related defense mechanisms. In the first chapter the author characterize the general biochemical mechanisms of the antioxidant cell defense, specifically the reactive oxygen species (EROs) formation and its chemical singularities and the induced oxidative stress, the enzymatic antioxidant defense system, specifically the superoxide dismutase (SOD) and Catalase (CAT) enzymes, the non-enzymatic mechanisms against the stress, including the Ascorbate-Glutathione cycle, the GSH (reduced glutathione), the phytochelatins and also proline formation. The plant nutritional status during the stress is crucial in order to maintain a proper defense response. In view of this, the chapter two is a published review about the participation of Sulfur (S) on the stress defense. This nutrient has a role in fundamental processes such as electron transport, structure, regulation and it is also associated with photosynthetic oxygen production, abiotic and biotic stress resistance and secondary metabolism. Moreover, few chemical elements are considered benefic to plants, while Selenium (Se) is the most relevant. In the chapter three the author describes the role of Se to detoxify the stress induced by heavy metal contamination, its powerful antioxidant characteristics and the improvement of the antioxidant enzymes activity and overall defense mechanisms. The chapter four consists of a scientific project conducted by the author. The aim of this study was to investigate whether Selenium, under the form of selenite (Na2SeO3), may avoid the uptake, translocation and concentration of Cadmium (CdCl2), in different tomato tissues, indicating possible mechanisms to counteract the stress, as well as to analyze the fruits overall status through the nutritional analyses, dry weight, pigments and proline concentration. The results demonstrate that alleviating effect of Se in tomato under Cd contamination could be related to restriction of Cd2+ uptake and translocation, enhancing micronutrient concentration in fruits and, finally, enhancing fruit proline concentration.
CAPES: 445978/2014-7
Peschke, Simon [Verfasser], and Dirk [Akademischer Betreuer] Johrendt. "Synthesis and characterization of rare-earth oxide transition-metal arsenides and selenides / Simon Peschke ; Betreuer: Dirk Johrendt." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2017. http://d-nb.info/1130587436/34.
Повний текст джерелаJolley, Dianne F., and n/a. "The accumulation and storage of selenium in Anadara Trapezia." University of Canberra. Applied Science, 1999. http://erl.canberra.edu.au./public/adt-AUC20060802.172608.
Повний текст джерелаSafoula, Gabriel. "Caracterisation des couches minces polycristallines de selenium dope par un halogene (cl, i) et etude des interfaces metal-selenium (m = cr, bi, te)." Nantes, 1988. http://www.theses.fr/1988NANT2018.
Повний текст джерелаLayer, Teresa. "Synthesis and characterisation of novel phosphorus and selenium substituted carbonyl clusters of ruthenium and osmium." Thesis, University of Cambridge, 1993. https://www.repository.cam.ac.uk/handle/1810/272563.
Повний текст джерелаNorris, Pauline Rose Hack. "Arsenic and Selenium Distribution in Coal-Fired Plant Samples." TopSCHOLAR®, 2009. http://digitalcommons.wku.edu/theses/52.
Повний текст джерелаWessels, Charlotte Elize. "Reduction of selenium by Pseudomonas Stutzeri NT-l; Growth reduction and kinetics." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/62802.
Повний текст джерелаDissertation (MEng)--University of Pretoria, 2017.
Chemical Engineering
MEng
Unrestricted
Waddell, Paul G. "Metal-chalcogen-nitrogen ring complexes and crystallographic studies." Thesis, University of St Andrews, 2010. http://hdl.handle.net/10023/987.
Повний текст джерелаJain, Rohan. "Biogenic nanoparticles of elemental selenium : synthesis, characterization and relevance in wastewater treatment." Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1178/document.
Повний текст джерелаNanoparticles exhibit many unique properties as compared to the bulk materials owning to their high surface to volume ratio. Elemental selenium nanoparticles also exhibit novel properties that are exploited in formation of solar cells, semiconductor rectifiers and removal of mercury and copper. However, the chemical synthesis of elemental selenium nanoparticles is costly, requires specialized equipments and uses toxic chemicals. On the other hand, biological production of elemental selenium nanoparticles (BioSeNPs) can be a green replacement for the chemically produced ones.BioSeNPs are produced by microbial reduction of selenite and selenate. The source of the selenium oxyanions can be the wastewaters, where microbial reduction is employed as a remediation technology for the removal of selenium. The formed BioSeNPs are colloidal poly-disperse particles with negative surface charge and are present in the effluent of the microbial reactor. However, the properties of these BioSeNPs are not very well understood. This knowledge would help us to produce better quality selenium nanomaterials, exploit produced BioSeNPs in the wastewater treatment and control the fate of these BioSeNPs in the microbial reactors. The characterization of BioSeNPs revealed the presence of the extracellular polymeric substances (EPS) on the surface of BioSeNPs. The EPS was identified to control the surface charge and to some extent the shape of the BioSeNPs. It was also found that the microbial reduction at 55 and 65 °C can lead to the formation of selenium nanowires as compared to nanospheres when the reduction takes place at 30 °C. These selenium nanowires are present in trigonal crystalline structure and are colloidal suspension, unlike the chemically formed trigonal selenium nanorods. This colloidal nature is due to negative ζ-potential values owning to the presence of EPS on the surface of biogenic selenium nanowires. Since proteins are a major component present in the EPS, the presence of various proteins on the surface of BioSeNPs was determined. The interaction of the various amino acids with the BioSeNPs was also evaluated.The interaction of heavy metals and BioSeNPs was studied with a view of developing a technology where BioSeNPs present in the effluent of an upflow anaerobic sludge blanket (UASB) reactor are mixed with heavy metals containing wastewater leading to removal of both BioSeNPs and heavy metals. It was found that Cu, Cd and Zn can be effectively adsorbed onto BioSeNPs. Cu was 4.7 times preferentially adsorbed onto BioSeNPs. The interaction of BioSeNPs with the heavy metals led to less negative ζ-potential of BioSeNPs loaded with heavy metals and thus better settling of BioSeNPs was achieved. The presence of BioSeNPs in the effluent of the microbial reactor treating selenium oxyanions containing wastewaters is undesirable due to higher total selenium concentrations. Thus, the attempts to capture of these BioSeNPs in the biomass/bioreactors were made. The activated sludge reactor system was investigated to aerobically reduce selenite to BioSeNPs and trap them in the activated sludge flocs. Around 80% of the fed selenium was trapped in the biomass. Sequential extraction revealed that the trapped selenium is BioSeNPs. The trapping of BioSeNPs in the sludge improved the settleability and hydrophilicity of the activated sludge flocs. When the UASB reactor were operated under mesophilic and thermophilic conditions, the total selenium concentration in the effluent under thermophilic conditions were lower than that of observed in mesophilic conditions suggesting better trapping of BioSeNPs.Keywords: Selenium, bioreduction, BioSeNPs, EPS, ζ-potential, heavy metals, activated sludge, UASB reactors, thermophilic
Tong, Yongfeng. "Self-Assembly of Organic Molecules on Reactive Metal Substrates." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS522/document.
Повний текст джерелаIn this thesis, the formation of self-assembled monolayers of different chalcogenide molecules and planer π-conjugated molecules and their electronic and structural characteristics were systematically studied mainly by synchrotron based X-ray photoelectron spectroscopy, scanning tunneling microscopy and low energy electron diffraction. A study of formation of hybrid organic-inorganic self assembled structure was performed by layer by layer assembly of a dithiol on ZnO(0001) with intermediate metal deposition. Additionally as a complement to the study of chalcogen head group molecules the adsorption characteristics of selenium and sulfur were investigated. The high resolution XPS and near edge absorption fine structure spectroscopy allowed to investigate the characteristics of self-assembled monolayers of benzene selenide and selenophene on Cu (100), and dihexyldiselenide on Ni(111) and Pd(111) and showed in particular the existence of Se-C bond breaking processes and existence of different adsorption sites of molecules. These conclusions were supported by the study of atomic selenium adsorption, which also shows existence different adsorption sites for the atomic Se with different chemical environments. These conclusions are mainly based on high resolution XPS study of characteristic Se3d, Se3p spectra, valance band spectrum and LEED imaging. The formation of a 5,5- bis (mercaptomethyl)-2,20- bipyridine (BPD) with SH termination on ZnO(0001) was demonstrated allowing subsequent grafting of Ag and Ni and further assembly of BPD on this metal-dithiol layer. The changes in electronic properties were determined from valence band spectra. The large π-conjugated molecule, NTCDA, was deposited on different metal surfaces and its structure morphology and chemical properties with respect to the metal surface was investigated. The NTCDA molecules displays a lying down structure with two different domains on Ag (110) and Cu(100) but three domain on Cu(111) surface. Compared with the one on the inert Au surface, a strong interface interaction between the molecules and Cu, Ag substrates plays an important role in determining the orientation and bonding state of the organic films
Bello, Yusuf O. "Tellurium and selenium precipitation from copper sulphate solutions." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/95895.
Повний текст джерелаENGLISH ABSTRACT: The copper sulphate leach solutions produced during the final pressure leach stages in base metal refinery processes contain low concentrations of other precious metals (OPMs, namely Rh, Ru and Ir ) and impurities in addition to the base metals (BMs) of interest. Se and Te impurities, in particular, must be removed from the leach solution before it is fed to copper electrowinning because these species have adverse effects on electrowinning efficiency. Currently, these elements are being precipitated from the leach solution with sulphurous acid. Se precipitation is satisfactory but Te removal still proves challenging. Previous studies have shown that tellurium can either be precipitated as cuprous telluride from copper sulphate solutions by reduction with sulphurous acid alone, or by the addition of SO2 as a precipitating agent and metallic copper as an additional precipitating agent. The objective of this study was to evaluate the effects of different process variables on Te and Se recovery in order to propose operating conditions at which increased tellurium precipitation can be achieved with minimal co-precipitation of base metals of interest (notably Cu and Ni). This would also aid in the development of a better understanding of tellurium and selenium precipitation mechanisms in CuSO4-H2SO4 medium.
AFRIKKANSE OPSOMMING: Die kopersulfaat logingsoplossing wat gedurende die finale druklogingstadia in basis metaal raffinaderye produseer word bevat, behalwe vir die basis metale van belang, ook lae konsentrasies ander edelmetale (AEM, naamlik Rh, Ru, en Ir) sowel as onsuiwerhede. Se en Te onsuiwerhede, in die besonder, moet vanuit die logingsoplossing verwyder word voordat die oplossing na die koper elektrowinning gevoer word omdat hierdie spesies negatiewe effekte op die elektrowinning effektiwiteit het. Hierdie elemente word tans met swaweligsuur vanuit die logingsoplossing gepresipiteer. Se presipitasie is voldoende, maar die Te verwydering bly steeds problematies. Vorige studies het getoon dat tellurium as kuprotelluried vanuit kopersulfaat oplossings presipiteer kan word deur middel van reduksie met swaweligsuur alleen, of met die byvoeging van SO2 as presipiteermiddel en metallieke koper as addisionele presipiteermiddel. Die doelwit van hierdie studie was om die effekte van verskillende prosesveranderlikes op Te en Se presipitasie te ondersoek ten einde bedryfstoestande voor te stel wat verbeterde tellurium presipitasie toelaat met minimale kopresipitasie van basis metale van belang (hoofsaaklik Cu en Ni). Dit sal ook bydra tot die ontwikkeling van ʼn beter begrip van die tellurium en selenium presipitasie meganisme in ʼn CuSO4-H2SO4 medium.
Mei, Jenny J. "The relationship between dietary and supplemental selenium, magnesium, zinc, and copper intake and depression score in older adults." Thesis, California State University, Long Beach, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10105270.
Повний текст джерелаThe importance of investigating relationships between depression and mineral intake is necessary due to concerns over the mental health and nutrition status of the growing older adult population in America. Due to lack of research in this area, the development of nutrition therapies for depressed older adults with special consideration for minerals is hindered. This study explored whether mean depression scores significantly differed between quartile intake groups of selenium, magnesium, zinc, and copper in a nationally representative sample of older adults (n = 901) from the 2011-2012 National Health and Nutrition Examination Survey (NHANES). For all four minerals, those within the highest quartile of intake had significantly lower depression scores than those within the lowest quartile. Nutrition and mental health care professionals should be aware of a possible association between mineral intake and depression and emphasize healthy eating patterns and nutrient-dense diets to maintain optimal mental and physical functioning.
DeNicola, Cafferky Katie. "ASSESSMENT OF METAL CONCENTRATIONS AND SPECIES IN BIOLOGICALLY RELEVANT SAMPLES WITH INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRIC TECHNIQUES." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1155754956.
Повний текст джерелаMilner, Harry. "The use of O-(diphenylphosphinyl)hydroxylamines and nitrogen-selenium ylides in transition-metal-free aminations of sp2 carbon centres." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/25510.
Повний текст джерелаCarroll, Brett Ian. "Microbial and Geochemical aspects of Selenium cycling in an Estuarine system: Lake Macquarie N.S.W." University of Sydney, Chemical Engineering, 1999. http://hdl.handle.net/2123/378.
Повний текст джерелаMoffo, Nathan. "Differential Analysis of Unique Genes Expressed in Stenotrophomonas maltophilia Strain OR02 in Response to Selenite." Youngstown State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ysu15663177454459.
Повний текст джерелаKruger, John Scott. "Synthesis and characterization of several novel aluminum and gallium phosphates templated by cobalt complexes." Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/30553.
Повний текст джерелаKirby, Jason K., and n/a. "Trace metal and metalloid accumulation, distribution, and, speciation in Lake Macquarie, N.S.W., Australia." University of Canberra. Resource, Environmental & Heritage Sciences, 2005. http://erl.canberra.edu.au./public/adt-AUC20051129.124508.
Повний текст джерелаYathavakilla, Santha Venkata. "Speciation of Selenium, Mercury and Arsenic in Food by Inductively Coupled Plasma Mass Spectrometry." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1179516979.
Повний текст джерелаZhang, Julie Zhiling. "The Toxicity Assessment of Heavy Metals and Their Species in Rice." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1249602453.
Повний текст джерелаStaicu, Lucian. "Production of colloidal biogenic elemental selenium and removal by different coagulation-flocculation approaches." Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1180/document.
Повний текст джерелаSelenium (Se) is a chalcogen element with a narrow window between essentiality and toxicity. The toxicity is mainly related to the chemical speciation that Se undergoes under changing redox conditions. Se oxyanions, namely selenite (Se[IV], SeO32-) and selenate (Se[VI], SeO42-), are water-soluble, bioavailable and toxic. In contrast, elemental selenium, Se(0), is solid and less toxic. Nevertheless, Se(0) nanoparticles are potentially harmful as particulate Se(0) has been reported to be bioavailable to filter feeding mollusks (e.g. bivalves) and fish. Furthermore, Se(0) is prone to re-oxidation to toxic SeO32- and SeO42- when discharged into aquatic ecosystems. Biogenic Se(0) under investigation was produced by the reduction of Na2SeO4 under anaerobic conditions using a mixed bacterial inoculum (anaerobic granular sludge) and through the reduction of Na2SeO3 under aerobic conditions using a pure microbial culture (Pseudomonas moraviensis stanleyae, a novel strain identified and characterized for the first time herein). Both types of Se(0) showed strong colloidal stability within the 2-12 pH range. The colloidal stability is caused by the negatively charged (-15 mV to -30 mV) biopolymer layer covering biogenic Se(0) particles and by their nanometer size. The particle size of Se(0) produced by anaerobic granular sludge ranged between 50 and 300 nm, with an average size of 166 nm. Conversely, the Se(0) particles produced by Pseudomonas moraviensis stanleyae are characterized by a lower diameter (~ 100 nm).The solid-liquid separation potential of Se(0) was assessed by centrifugation, filtration, coagulation-flocculation and electrocoagulation. While all approaches can bring about Se(0) removal from suspension with various degrees of success, electrocoagulation using iron sacrificial electrodes showed the highest removal efficiency (97%). Because biogenic Se(0) is harmful to the environment, appropriate measures must be implemented for the solid-liquid separation using an efficient technology
Mohammadi, Farid. "A Meta-Analysis on Solar Cell Technologies." Thesis, Mittuniversitetet, Avdelningen för elektronikkonstruktion, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-32584.
Повний текст джерелаSENCE, MARTINE. "Etude des proprietes optiques du seleniure de cadmium sous hautes intensites d'excitation lumineuse." Université Louis Pasteur (Strasbourg) (1971-2008), 1989. http://www.theses.fr/1989STR13021.
Повний текст джерелаTaylor, Anne Marie, and n/a. "Biomarkers of Cadmium, Lead and Selenium Toxicity in the Marine Bivalve Molluscs Tellina deltoidalis and Anadara trapezia: Linking Exposure, Dose and Response." University of Canberra. Environmental Science, 2009. http://erl.canberra.edu.au./public/adt-AUC20091214.104734.
Повний текст джерелаMoreno, Achurra Ana Karina. "Revisión meta-analítica del efecto de selenio orgánico sobre la retención a nivel muscular y la actividad de glutatión peroxidasa en peces." Tesis, Universidad de Chile, 2012. http://www.repositorio.uchile.cl/handle/2250/112230.
Повний текст джерелаEl selenio es un mineral traza esencial en la nutrición animal, y posee funciones importantes relacionadas con el sistema antioxidante del organismo. Actualmente los mercados se encuentran dirigidos a una producción más limpia y que implique menores costos para su obtención. Es por esto que surge la idea de suplementar las dietas de peces con selenio orgánico, ya que aumenta su absorción y retención, conllevando con ello un aumento en la biodisponibilidad del mineral. Para evaluar esto, se realizó un meta-análisis, el cual permitió contrastar los resultados obtenidos por siete autores en relación a la suplementación de selenio orgánico en la alimentación de peces y su efecto en la retención de este mismo a nivel muscular y la actividad de la enzima glutatión peroxidasa a nivel plasmático y hepático. Los resultados obtenidos de los estudios fueron llevados a una métrica común mediante el cálculo del índice del tamaño del efecto. A partir de él, se obtuvo la estimación del efecto global (d·), con valores de 2,279, 1,085 y 1,884 para las variables, retención de selenio a nivel muscular, actividad de la enzima glutatión peroxidasa a nivel plasmático y actividad de la enzima glutatión peroxidasa a nivel hepático respectivamente, siendo este efecto alto en cada una de las variables. La homogeneidad calculada entre los estudios presentó valores de p-value iguales a 9,96·10-9, 8,9·10-1 y 7,88·10-3 para cada una de las variables respectivamente, presentando para cada variable heterogeneidad entre los resultados analizados. En tanto, la comparación realizada entre las fuentes de selenio (selenito de sodio y selenometionina), indicó que con un p-value 9,955·10-9 y 7,88·10-3 para retención a nivel muscular y actividad a nivel hepático respectivamente, existe diferencia significativa entre las fuentes, por lo que la selenometionina aumentaría la retención a nivel muscular y la actividad de la enzima a nivel hepático, mientras que con un p-value de 8,6·10-1 no se presenta diferencia entre las fuentes para actividad enzimática a nivel plasmático. Los estudios con mayor influencia en el cálculo del efecto global para cada una de las variables fueron los de Lorentzen et al. (1994) y Wang et al. (2004) para la variable retención a nivel muscular, Lorentzen et al. (1994) y Liu et al. (2010) para actividad enzimática a nivel plasmático y los estudios de Zhou et al. (2009) y Raider et al. (2010) para actividad enzimática a nivel hepático. Estos estudios son además, los que presentaron el mayor cambio en magnitud en la estimación del efecto global al removerlos del meta-análisis y graficar el efecto provocado por su ausencia en el análisis de sensibilidad.
Selenium is a trace mineral which is essential in animal nutrition and has important functions related to the antioxidant system of the organism. At present fish farming markets are oriented towards a cleaner production involving lower costs. Based on this, supplementing fish diets with organic selenium arose as a feasible idea since this mineral increases its absorption and retention, which leads to an increase in the bioavailability of the mineral. To evaluate this possibility, a meta-analysis was carried out to contrast the results obtained by seven authors in relation to supplementing fish feed with organic selenium and its effect on the retention of this mineral at the muscle level and on the activity of the glutathione peroxidase enzyme at plasma and hepatic levels. The results obtained from the above studies were transformed to a common metric by means of the effect size estimation. Based on it, an estimate of the global effect (d·) was obtained with values of 2.279, 1.085, and 1.884 for the variables selenium retention at muscle level, activity of the glutathione peroxidase enzyme at plasma level and activity of the glutathione peroxidase enzyme at hepatic level, respectively, this effect being high in each of the variables. Homogeneity calculated among the studies showed p-values of 9.96·10-9, 8.9·10-1 and 7.88·10-3 for each of the variables, respectively, thus presenting heterogeneity among the results analyzed for each variable. Meanwhile, the comparison among the sources of selenium, sodium selenite and selenomethionine indicated that with p-values of 9.955·10-9 and 7.88·10-3 for retention at muscle level and activity at hepatic level, respectively, there is a significant difference among the sources. Consequently, selenomethionine would increase retention at muscle level and the enzymatic activity at hepatic level, while with a p-value of 8.6·10-1 no difference exists among the sources for the enzymatic activity at plasma level. The studies with greater influence on the estimation of the global effect for each of the variables were those by Lorentzen et al. (1994) and Wang et al. (2004) for the variable retention at muscle level, those by Lorentzen et al. (1994) and Liu et al. (2010) for the enzymatic activity at plasma level, and those by Zhou et al. (2009) and Raider et al. (2010) for the enzymatic activity at hepatic level.