Дисертації з теми "SALT-METAL"

Щоб переглянути інші типи публікацій з цієї теми, перейдіть за посиланням: SALT-METAL.

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Ознайомтеся з топ-50 дисертацій для дослідження на тему "SALT-METAL".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.

1

Brooker, Alan Thomas. "New routes to metal salt complexes." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359761.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Emmerson, Richard Hugh Christian. "Salt marsh restoration by managed retreat : metal and nutrient fluxes." Thesis, Imperial College London, 1997. http://hdl.handle.net/10044/1/8454.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Lacombe, Marie. "Synthesis and metal salt binding properties of functionalised macrocyclic ligands." Thesis, University of Nottingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275160.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Khandelwal, Amit Harikant. "Lithium, sodium and lanthanide metal inorganic and organic salt complexes." Thesis, University of Cambridge, 1994. https://www.repository.cam.ac.uk/handle/1810/272664.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Alkhamis, Mohammad, and Mohammad Alkhamis. "Stability of Metal in Molten Chloride Salt at 800˚C." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/622893.

Повний текст джерела
Анотація:
The stability of Haynes 230 and Hastelloy C-276 nickel alloys exposed to high temperature molten salt with trace contaminants (i.e., water and oxygen) is found to be acceptable for using these metals to house anaerobic MgCl2-KCl and NaCl-KCl-ZnCl2 molten salts at 800oC. The corrosion rate determined by gravimetric tests range from -98 µm/year to 20. 13 µm/year at 800˚C. The corrosion rate is estimated to be 16.14 µm/year for Haynes 230 and 10.03 µm/year for Hastelloy C-276 based on the weight loss and surface area of the coupons when the coupons of Haynes 230 and Hastelloy C-276 alloys are immersed in molten MgCl2-KCl salt in sealed quartz containers and left in an oven at a temperature of 800˚C up to 16 days. The corrosion rate is estimated to be -20.46 µm/year for Haynes 230 and -7.36 µm/year for Hastelloy C-276 based on the weight loss and surface area of the coupons when the alloys are immersed in molten NaCl-KCl-ZnCl2 salt in sealed quartz containers and left in an oven at 800˚C up to 56 days. The corrosion rate of the alloys are well below the DOE requirement of 50 µm/year for the alloys in molten chloride salts to be considered acceptably stable. Ultimate tensile strength (UTS) after immersion of Haynes 230 and Hastelloy C-276 in molten salt ranged from 634 MPa to 860 MPa. The UTS of Haynes 230 is estimated to be 642 MPa after exposure to NaCl-KCl-ZnCl2 for 4 weeks at 800˚c and 841 MPa after exposure to MgCl2-KCl for 4 weeks at 800˚c compared to an untreated sample which achieved a UTS of 851 MPa. Likewise, the UTS of Hastelloy C-276 is estimated to be 692 MPa after exposure to NaCl-KCl-ZnCl2 for 4 weeks at 800˚c and 842 MPa after exposure to MgCl2-KCl for 4 weeks at 800˚c compared to an untreated sample which achieved a UTS of 830 MPa. Molten chloride salts, such as NaCl-KCl-ZnCl2 and KCl-MgCl2, are pretreated by heating and bubbling dry Argon gas in the salt in order to remove oxygen and water and thereby reduce the corrosion of metal containers of molten salt. Monitoring the relative humidity and percent oxygen of the exhaust gas during the sparging of dry Argon at 240 sccm into 150 g of molten chloride salt at 500˚C for NaCl-KCl-ZnCl2 and 700˚C for KCl-MgCl2 allows an estimation time to reach a low level of oxygen and water in the salt and to estimate the amount of oxygen and water removed. Results show water is more difficult to remove than oxygen from the salt. Ten minutes of sparging with dry argon brings oxygen content of exhuast gas to<0.1% O2. Approximately fifty minutes of sparging leaves the exhaust gas only containing<0.7% RH. The total moles of oxygen removed from the salts are estimated to be 0.0043 moles for molten NaCl-KCl-ZnCl2 and 0.0076 moles for KCl-MgCl2. The total moles of water removed from the NaCl-KCl-ZnCl2 salt is estimated to be 0.016108379 moles and 0.002321214 moles from molten KCl-MgCl2.
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Fatollahi-Fard, Farzin. "Production of Titanium Metal by an Electrochemical Molten Salt Process." Research Showcase @ CMU, 2017. http://repository.cmu.edu/dissertations/893.

Повний текст джерела
Анотація:
Titanium production is a long and complicated process. What we often consider to be the standard method of primary titanium production (the Kroll process), involves many complex steps both before and after to make a useful product from titanium ore. Thus new methods of titanium production, especially electrochemical processes, which can utilize less-processed feedstocks have the potential to be both cheaper and less energy intensive than current titanium production processes. This project is investigating the use of lower-grade titanium ores with the electrochemical MER process for making titanium via a molten salt process. The experimental work carried out has investigated making the MER process feedstock (titanium oxycarbide) with natural titanium ores|such as rutile and ilmenite|and new ways of using the MER electrochemical reactor to \upgrade" titanium ores or the titanium oxycarbide feedstock. It is feasible to use the existing MER electrochemical reactor to both purify the titanium oxycarbide feedstock and produce titanium metal.
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Saeed-Akbari, Semiramis [Verfasser]. "Minimizing Salt and Metal Losses in Mg-Recycling through Salt Optimization and Black Dross Distillation / Semiramis Saeed-Akbari." Aachen : Shaker, 2011. http://d-nb.info/1071529412/34.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Meyer, Joseph Freeman. "Recovery boiler superheater corrosion - solubility of metal oxides in molten salt." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47742.

Повний текст джерела
Анотація:
The recovery boiler in a pulp and paper mill plays a dual role of recovering pulping chemicals and generating steam for either chemical processes or producing electricity. The efficiency of producing steam in the recovery boiler is limited by the first melting temperature of ash deposits that accumulate on the superheater tubes. Above the first melting temperature, the molten salt reacts with the protective oxide film that develops and dissolves it. The most protective oxide is determined by evaluating how little it dissolves and how its solubility changes in the molten salt. Solubility tests were done on several protective oxides in a known salt composition from a recovery boiler that burns hardwood derived fuel. ICP-OES was used to measure concentration of dissolved metal in the exposure tests while EDS and XRD were used to verify chemical compositions in exposure tests. NiO was found to be the least soluble oxide while Cr₂O₃ and Al₂O₃ had similar solubility with Fe₂O₃ being less soluble than Cr₂O₃ but more soluble than NiO. Exposure tests with pure metals and selected alloys indicated that even though Fe₂O₃ has little solubility, it is not a protective oxide and causes severe corrosion in stainless steels. The change in performance of iron based alloys was due to the development of a negative solubility gradient for Fe₂O₃ where Fe₂O₃ precipitated out of solution and created a continuous leaching of oxide. Manganese was found to be beneficial in stainless steels but its role is still unknown. Nickel based alloys were found to be least corroded due to nickel's low solubility and because it did not form a negative solubility gradient.
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Tomlinson, Simon Michael. "Computer simulation studies of rock-salt structured binary transition metal oxides." Thesis, University College London (University of London), 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264941.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Spatocco, Brian Leonard. "Investigation of molten salt electrolytes for low-temperature liquid metal batteries." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/101461.

Повний текст джерела
Анотація:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2015.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 202-211).
This thesis proposes to advance our ability to solve the challenge of grid-scale storage by better positioning the liquid metal battery (LMB) to deliver energy at low levelized costs. It will do this by rigorously developing an understanding of the cost structure for LMBs via a process-based cost model, identifying key cost levers to serve as filters for system down-selection, and executing a targeted experimental program with the goal of both advancing the field as well as improving the LMB's final cost metric. Specifically, cost modelling results show that temperature is a key variable in LMB system cost as it has a multiplicative impact upon the final $/kWh cost metric of the device. Lower temperatures can reduce the total cost via simultaneous simplifications in device sealing, packaging, and wiring. In spite of this promise, the principal challenge in reducing LMB operating temperatures (>400°C) lies in identifying high conductivity, low-temperature electrolytes that are thermally, chemically, and electrochemically stable with pure molten metals. For this reason, a research program investigating a promising low-temperature binary molten salt system, NaOH-NaI, is undertaken. Thermodynamic studies confirm a low eutectic melting temperature (219°C) and, together with the identification of two new binary compounds via x-ray diffraction, it is now possible to construct a complete phase diagram. These phase equilibrium data have then been used to optimize Gibbs free energy functions for the intermediate compounds and a two-sublattice sub-regular solution framework to create a thermodynamically self-consistent model of the full binary phase space. Further, a detailed electrochemical study has identified the electrochemical window (>2.4 V) and related redox reactions and found greatly improved stability of the pure sodium electrode against the electrolyte. Results from electrochemical studies have been compared to predictions from the solution model and strong agreement supports the physicality of the model. Finally, a Na[/]NaOH-NaI[/]Pb-Bi proof-of-concept cell has achieved over 100 cycles and displayed leakage currents below 0.40 mA/cm℗ø. These results highlight an exciting new class of low-melting molten salt electrolytes and point to a future Na-based low-temperature system that could achieve costs that are 10-15% less than those of existing lithium-based LMBs.
by Brian Leonard Spatocco.
Ph. D.
Стилі APA, Harvard, Vancouver, ISO та ін.
11

Wright, Dominic S. "Novel complexes of alkali metal compounds, synthesised by the ammonium salt route." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306474.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
12

Duarte, Bernardo Afonso de Aranha Alhandra. "Metal biogeochemical cycling in tagus estuary salt marshes: from halophytes to microbes." Master's thesis, Universidade de Évora, 2011. http://hdl.handle.net/10174/15543.

Повний текст джерела
Анотація:
As zonas de sapal recebem habitualmente elevadas quantidades de poluentes provenientes das zonas urbanas circundantes, através da circulação estuarina e da inundação destas zonas pela maré. Por esta razão são frequentemente considerados sumidouros de poluentes, nomeadamente metais pesados. Quando se consideram os efeitos tóxicos dos metais pesados no ecossistema sapal e também na saúde pública, a sua concentração total não é tão importante como a forma química em que estes metais surgem. Esta forma vai ser determinante na a sua biodisponibilidade para serem tomados pelas plantas e consequentemente entrar na cadeia trófica. A actividade do sistema radicular das plantas e os microrganismos a elas associados alteram as propriedades físicas e químicas dos sedimentos, influenciando o fraccionamento químico dos metais e consequentemente a sua biodisponibilidade. Em zonas altamente poluídas, as espécies vegetais desenvolveram mecanismos de sobrevivência a concentrações elevadas de metais pesados, tornando-se tolerantes à contaminação por estes elementos. A absorção de metais depende de vários factores como o pH, a especiação química do elemento, a matéria orgânica do sedimento, entre outros. Adicionalmente, as raízes das plantas sintetizam, acumulam e secretam inúmeros compostos, como os ácidos orgânicos, modificando as características físico-químicas do sedimento e dos metais, influenciando a tomada de nutrientes e na desintoxicação de metais pesados. Durante este trabalho, pretendeu-se estudar como as diferentes espécies vegetais absorvem os metais, os incorporam na sua biomassa e como os libertam para o ambiente circundante durante a senescência dos seus órgãos. Pretende-se também investigar os processos microbianos de decomposição desta matéria vegetal contaminada e como estes vão afectar a especiação dos metais e consequentemente a sua disponibilidade para serem novamente absorvidos pelas plantas.A quantidade total de Zn, Cu, Cd e Co presente nas folhas, caules e raízes de Sarcocornia fruticosa, S. perennis, Halimione portulacoides e Spartina maritima foram analisados de dois em dois meses, num sapal do estuário de Tejo. Para todos os elementos as concentrações mais elevadas foram encontradas nas raízes, sendo as concentrações nos órgãos aéreos negligenciáveis no que diz respeito ao balanço de metais no sedimento, como é evidente, devido às baixas taxas de translocação raízparte aérea. Foram também avaliados outros parâmetros como a acumulação de metais, taxas de “turnover” radicular e coeficientes de reciclagem. Os elevados “turnovers” radiculares e coeficientes de reciclagem observados em S. maritima para a maioria dos metais tornam esta espécie, uma espécie fito-estabilizadora. Pelo contrário, o baixo “turnover” radicular e baixa geração de necromassa observada para S. perennis, tornam esta espécie a mais indicada para processos de fitorremediação. Assim, apesar das elevadas quantidades de metais devolvidos aos sedimentos, devidas à senescência radicular, os sapais continuam a poder ser considerados sumidouros de metais pesados, reciclando-os principalmente entre os sedimentos e as raízes dos halófitos. Considerando este mecanismo de tomada, reciclagem e senescência de biomassa contaminada, tornou-se de grande importância estudar também a decomposição desta mesma necromassa. Como caso de estudo, dirigiu-se a investigação destes mecanismos aos sedimentos de H. portulacoides. Numa base sazonal, avaliou-se a influência de enzimas extracelulares presentes nos sedimentos, na especiação química dos metais e na reciclagem da matéria orgânica do sedimento, de forma a melhor compreender a ligação entre estes mecanismos de reciclagem orgânica e as espécies químicas de metais associadas. A especiação metálica em sedimentos de H. portulacoides foi avaliada usando o método de Tessier, tendo evidenciado um padrão sazonal comum no que diz respeito à fracção de metais associados à matéria orgânica, apresentando valores elevados durante o Outono, ou seja, na estação do ano em que os valores de matéria orgânica se apresenta mais elevados. As fracções de metais associados à matéria orgânica, bem como a fracção residual, apresentam-se sempre dominantes, sendo as variações sazonais verificadas devidas principalmente ao intercâmbio de metais entre as duas fracções. As enzimas fenol oxidase e -N-acetilglucosaminase apresentam valores elevados de actividade durante a Primavera e Verão, contrariamente à peroxidase, que exibe o seu pico de actividade durante o Inverno. A enzima protease apresenta os seus valores de maior actividade durante a Primavera e Inverno. Estes períodos diferenciais de elevada degradação de matéria orgânica levam à existência de dois períodos de decréscimo de metais associados à matéria orgânica. Os picos de actividade da enzima sulfatase (Primavera e Inverno) coincidem com a depleção de metais sob a forma disponível, provavelmente devido à formação de sulfuretos e consequente mobilização dos metais. Todos estes factores mostram uma evidente interacção entre diversas enzimas microbianas, afectando a especiação metálica. Estes resultados levam à inevitável conclusão de que as plantas de sapal actuam como “sink” temporário de metais pesados. Apesar desta característica temporária, as plantas de sapal continuam exercer uma grande influência na biogeoquímica do ambiente circundante. Este ciclo é completado durante o período de senescência, geração de necromassa e consequente reintrodução de metais no ambiente circundante, em formas químicas diferentes. Durante este processo, outro factor que assume uma elevada importância será a reciclagem biogeoquímica mediada pela comunidade microbiana existente na rizosfera, decompondo a matéria orgânica e desta forma actuando sobre as ligações estabelecidas entre esta e os metais pesados, afectando novamente a especiação química dos metais. Devido a este mecanismo, a nova tomada de metais por parte das plantas poderá ser potenciada ou inibida, reiniciando desta forma o ciclo dos metais. Num ambiente de tão grande complexidade, com todos estes processos a ocorrer, torna-se evidente que todas estas variáveis actuam em conjunto, tornando os sapais ecossistemas ideais para o estudo da fitorremediação e das suas possibilidades de aplicação em zonas contaminadas; ABSTRACT:Salt marshes usually receive high inputs of pollution from nearby urban areas, river transport and tidal inundation. They are considered to act as sinks for pollutants, namely heavy metals. When we consider possible toxic effects of metals to the marsh ecosystem and also to human health, the total amount of metal is not as important as the chemical form in which it is present. This form will be responsible for the bioavailability to the plant uptake and consequently to the introduction in the food web. The activity of plant roots and associated microbes can alter the physical and chemical properties of the sediment, influencing the chemical fractionation of metals and thus bioavailability. In highly contaminated sites plant species have developed mechanisms to survive with highly toxic concentrations, becoming therefore tolerant to heavy metal pollution. The absorption of metals depends on varying factors such as pH, metal speciation and soil organic matter, among others. Plant roots can synthesize, accumulate and secrete many compounds, such as organic acids that will modify the sediment and metals physical and chemical characteristics, influencing nutrient uptake and heavy metal detoxification. In this study was investigated how the different plant species uptake heavy metals, incorporate them in their biomass and how these metals will return back into the surrounding environment, due to the plant organ senescence. It was also an objective of this study to investigate the microbial decomposition processes of this contaminated vegetable material and how this affects the metal speciation and consequently their availability to be uptake back into the plants. Pools of Zn, Cu, Cd and Co in leaf, stem and root tissues of Sarcocornia fruticosa, S. perennis, Halimione portulacoides and Spartina maritima were analysed every two months, in a Tagus estuary salt marsh. All the major concentrations were found in the root tissues, being the concentrations in the aboveground tissues/organs neglectable for sediment budget proposes, as seen by the low root-aboveground translocation. Metal annual accumulation, root turnovers and cycling coefficients were also assessed. S. maritima showed the higher root turnovers and cycling coefficients for most of the analysed metals, making this a phyto-stabilizer species. By the contrary the low root turnover, cycling coefficient and low root necromass generation makes S. perennis the most suitable species for phytoremediation processes. Although the high amounts of metal return to the sediments, due to root senescence, salt marshes can still be considered sinks of heavy metals, cycling heavy metals mostly between sediment and root. With this it became of great importance to study also the decomposition of the highly contaminated root necromass by the microbial community existent in the rhizosediment. For this, H. portulacoides rhizosediment microbial processes were evaluated, as a case study. The influence of salt marsh sediment extracellular enzymatic activity (EEA) on metal fractions and organic matter cycling was evaluated on a seasonal basis, in order to study the relation between organic matter cycling and the metal species associated. Metals in the rhizosediment of H. portulacoides were fractioned according to the Tessier’s scheme and showed a similar pattern concerning the organic bound fraction, being always high in autumn, matching the season when sediment organic matter presented higher values. Both organic bound and residual fractions were always dominant, being the seasonal variations mostly due to interchanges between these fractions. Phenol oxidase and -N-acetylglucosaminidase had higher activities during spring and summer, contrarily to peroxidase, which had it higher activity during winter. Protease showed high activities in both spring and winter. These differential periods of high organic matter degradation caused two periods of organic bound metals decrease. Sulphatase peaks (spring and winter) matched the depletion of exchangeable forms of metals, probably due to sulphides formation and consequent mobilization. This showed an interaction between several microbial activities affecting metal speciation. These findings lead to the inevitable conclusion that vascular plants may act as temporary sinks for heavy metals. Although this temporal sinking characteristic, they continue to influence the biogeochemistry of the surrounding environment. The cycle becomes complete with senescence, necromass generation and consequent re-input of metals to the surrounding environment in a different chemical form. Another key factor at this point will be the biogeochemical cycling by the microbial community inhabiting the rhizosphere, decomposing organic matter, acting this way on the bonds established with heavy metals and again the chemical speciation is affected. With this a new uptake is enhanced or delayed and the process restarted. In such a complex environment with all these processes acting, it becomes evident that all the variables are gathered to make salt marshes ideal ecosystems to study phytoremediation and its possibilities of application in other contaminated areas.
Стилі APA, Harvard, Vancouver, ISO та ін.
13

Hung, Grace Ann. "Metal accumulation in surface sediments of salt marshes in the Bay of Fundy." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98728.

Повний текст джерела
Анотація:
One of the most recognised values of tidal salt marshes is the ecosystem service they provide as natural sinks for contaminants such as metals. This study examines net accumulation of metals (As, Cr, Cu, Hg, Ni, Pb, Zn and V) over a 5-yr period, from 1997 to 2002, in surface sediments of salt marshes in the Bay of Fundy, Canada. Metal accumulation has been measured in seven sites that extend from outer to inner Bay and in low and high marsh areas within each site. Overall, sediment metal concentrations are at or near their natural levels. Concentrations of metals show variability among marshes but are not significantly different between low and high marsh. Concentrations of As, Hg, Pb and V appear to be influenced by anthropogenic inputs. Calculated sediment loading rates for these metals generally showed gradients of increased loading from outer to inner Bay. Variability in sediment deposition rate is the driving force behind this spatial pattern. Results of this study suggest that the value of salt marshes as a sink for metals may be enhanced by high sedimentation rates.
Стилі APA, Harvard, Vancouver, ISO та ін.
14

Johnson, Adam Nicholas. "Toxicological Comparison of Heavy Metal Salt and Semiconductor Nanoparticle Exposure in Zebrafish (Danio rerio)." Fogler Library, University of Maine, 2007. http://www.library.umaine.edu/theses/pdf/JohnsonAN2007.pdf.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
15

Tanaka, Reid S. "Quantifying the adhesion of noble metal foulants on structural materials in a Molten Salt Reactor." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/112520.

Повний текст джерела
Анотація:
Thesis: S.M., Massachusetts Institute of Technology, Department of Nuclear Science and Engineering, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 145-149).
As discovered during the Molten Salt Reactor (MSR) Experiment (MSRE), selected fission products deposited on the wetted surfaces throughout the reactor. Fission products such as molybdenum and ruthenium are noble with respect to the electrochemical potential of the fluoride fuel salt and therefore remain insoluble in their elemental forms rather than becoming ionic salts. Coalescing in the primary fluid, these noble metals then migrate and eventually deposit on internal reactor surfaces. Since the bulk of these noble metal fission products are also energetically unstable they bring not only physical fouling, but heat and radiation from decay as well. The adherence forces of five of the seven principal radioactive foulants discovered during the MSRE were measured on six different potential structural materials by atomic force microscope force spectroscopy (AFM-FS). The noble metals studied were niobium, molybdenum, ruthenium, antimony and tellurium. Structural materials measured were Hastelloy-N, the primary structural metal of the MSRE; two steels, SS316L and F91; commercially pure nickel and molybdenum; and silicon carbide. MSRs operate with surfaces free of passivating corrosion layers, so the measurements were conducted on bare metal surfaces. An argon ion gun chamber was constructed for removal of the oxide layers from mechanically polished substrate metals by sputtering. A combination vacuum chamber/glove box was crafted to accept the sputter polished substrates into a dry, inert environment where the force adhesion measurements were made. Data acquired in the last phase of the study partially demonstrated the concept. The measured particle-to-substrate attractive forces found antimony and tellurium to be generally more adherent to the bare metals than niobium or molybdenum. The finding is consistent with the fouling examined in the MSRE. If held, this correlation of laboratory measurement to actual fouling may aid the reactor designer in anticipating fouling to plan for the effects. Such knowledge would inform selection of plant materials, both for operating components such as flow detectors and heat exchangers, where fission product deposition would be undesired, and for processing components such as filters and metal collection systems, where adhesion would be preferred.
by Reid S. Tanaka.
S.M.
Стилі APA, Harvard, Vancouver, ISO та ін.
16

Zhang, Zhenjie. "Template-Directed Synthesis and Post-Synthetic Modification of Porphyrin-Encapsulating Metal-Organic Materials." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5162.

Повний текст джерела
Анотація:
Metal-organic materials (MOMs) represent an emerging class of materials comprised of molecular building blocks (MBBs) linked by organic linker ligands. MOMs recently attract great attention because of their ability to exhibit permanent porosity, thereby enabling study of properties in the context of gas storage, gas separation, solid supports for sensors, catalysis and so on. Although MOMs have been studied for over 60 years, the porous nature of MOMs was not systematically and widely explored until the early 1990's. This may be one of the reasons why template-directed synthesis of MOMs remains relatively underexplored, especially when compared to other classes of porous material (e.g. zeolite and mesoporous silicates). However, the study of template-directed synthesis exhibits great significance to the research field of MOMs as these considerations: (i) to access analogues of prototypal MOM platforms that cannot be prepared directly; (2) to create porous materials with new topologies; (3) to transfer the functionality of templates to MOMs; (4) to exert fine control over structural features. In this dissertation, I chose a functional organic material, porphyrin, as templates and succeeded to synthesize a series of porphyrin-encapsulating MOMs, (porph@MOMs), in which the porphyrins were encapsulated inside the cavities as guests. Porphyrins molecules can template the formation cavities with different shapes and sizes (e.g. triangle, square or hexagon) to accommodate the porphyrins molecules when organic ligands with different size and symmetry were utilized during the synthesis. On the other hand, the porphyrins molecules can also template the formation of octahemioctahedral cages or hexahedron cages with porphyrins trapped inside, which further built the tbo, pcu, rtl, zzz, mzz networks. By selecting templated porph@MOMs as platforms, post-synthetic modifications (PSMs) of porph@MOMs were further studied. A cadmium MOM, porph@MOM-10, can undergo PSM by Mn(II) or Cu(II) via single-crystal-to-single-crystal processes. The Mn- and Cu- exchanged PSM variants exhibit catalytic activity for epoxidation of trans-stilbene. Porph@MOM-11 can serve as a platform to undergo a new PSM process involving cooperative addition of metal salts via single-crystal-to-single-crystal processes. The incorporation of the salts leads to higher H2 and CO2 volumetric uptake and higher CO2 vs CH4 selectivity. Porph@MOM-11 was also found to be a versatile platform that can undergo metal ion exchange with Cu2+ in single-crystal-to-single-crystal fashion. The use of mixed metal salt solutions (Cu2+/Cd2+) with varying ratios of metal salts enabled systematic study of the metal exchange process in porph@MOM-11 in such a manner that, at one extreme, only the Cd porphyrin moieties undergo metal ion exchange, whereas at the other extreme both the framework and the porphyrin moiety are fully exchanged. It is also observed that a concerted PSMs approach of metal ion exchange and ligand addition towards a porphyrin-walled MOM, porphMOM-1 affords a porphyrin-encapsulating MOM, porph@MOM-14, in which porphyrin anions are encapsulated in the octahemioctahedral polyhedral cage via weak interactions. Beside of the template-directed synthesis and post-synthetic modification of porph@MOMs, pre-synthetic control of metal-organic materials' structures was also studied in this dissertation. Due to the partial flexibility of 1,3-benzenedicarboxylate linkers, kagom[eacute] lattice and NbO supramolecular isomers were observed from a complexation of bulky 1,3-benzenedicarboxylate ligand to Cu(II) paddlewheel moieties. In addition, a new family of hybrid nanoball vanadium MOM structures (Hyballs) was prepared by the self-assemble of trimesic acid with tetranuclear and pentanuclear vanadium polyoxometalates. These hyballs are robust, permanently porous and their exterior surfaces facilitate cross-linking via hydrogen bonds or coordination bonds to generate pcu networks.
Стилі APA, Harvard, Vancouver, ISO та ін.
17

Fernandes, Célia Carolina Moreira. "H. portulacoides and J. maritimus in a mercury contaminated salt marsh: metal accumulation, biochemical and lipidomic patterns." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22320.

Повний текст джерела
Анотація:
Mestrado em Biologia Molecular e Celular
The salt marshes, one of the most productive ecosystems, serves as the sink for contaminants, namely metals from industries, reducing in this way the contamination of surrounding ecosystems. Although, as levels of contaminants, the ability of salt marshes to incorporate wastes can be impaired. In the aquatic environment, high mercury (Hg) pollution is mainly due to metal discharge of effluents from chloralki plants containing high concentrations of this metal. Mercury has been recognized as heavy metal and extremely toxic to plants interfering with several crucial cellular processes. This study evidenced the importance to understand the analysis that plants under environmental exposed to Hg and to evaluate impact of Hg toxicity in plants salt marsh communities. Better knowledge on these accumulation aspects will evaluate the stress imposed by Hg on primary production in salt marsh plants and adaptation of mobility of the metal in the ecosystem. As well as the molecular mechanisms mercury tolerance, which are important to clean efficiently Hg contaminated systems in order to an effective restoration is achieved. In this way, the work focused on two species of halophytes, Halimione portulacoides and Juncus maritimus collected at two sites of the Ria de Aveiro contaminated by mercury, considered s1 as less contaminated site and s2 as the most contaminated site. Thus, this work was designed to (1) evaluate how Hg distribution in plants would avoid high Hg concentrations (2) which way plants would retain Hg toxicity by triggering antioxidant responses. Indeed, most of biochemical parameters determinate the evidence of different responses by different concentration of Hg in the sediment (s1 and s2) and (3) plants can or not modify their lipid composition by Hg toxicity through the UPLC-MS methodology. This study demonstrated that both plant species restricted Hg uptake. However, the process was more efficient in H. portulacoides. Was observed differences in the amount of Hg accumulated by both species. Allocation patterns also differs between species. H. portulacoides showed different levels of Hg between leaves, stems and roots, while J. maritimus accumulated the higher levels of Hg in roots. The conjugation of both process, absorption and translocation resulted in similar Hg concentrations in stems and leaves and much higher Hg levels in J. maritimus roots. The results obtained demonstrate that Hg generated oxidative damage in the roots of both species and in leaves of H. portulacoides. Differences in LPO between species obtaining for each specie reflects not only the level of Hg accumulated and Hg distribution but also the ability to trigger the defense mechanisms. J. maritimus was able to increase the protein levels and DHAR activity in roots and rhizomes and GSTs in rhizomes. H. portulacoides was not able to induce the antioxidant enzymatic responses. Although in leaves antioxidant molecules such carotenoids and α-tocopherol were enhanced. In lipidome study, species also showed differences. In H. portulacoides, phospholipids decreased in all the organs analyzed, which can subject an alteration of membrane permeability. In addition, galactolipids decreased, reducing the efficiency on photosynthesis. However, α-tocopherol increased, and so better protection to chloroplast membranes and maintenance of photosynthetic activity provided. In J. maritimus, lipid changes were only detected in roots and rhizomes, increasing lipid permeability and explaining the higher bioaccumulation at high Hg concentrations. Phyto sterols decreased significantly in roots and lead to alterations of permeability membrane. α-tocopherol was detected in both organs of J. maritimus, a decrease that demonstrate an ineffective Hg contamination. This study may be a starting point for further work, namely in other marshes, in other species and with other metals. Understanding the mechanisms inherent to in heavy metal tolerance in marsh plants and the changes in lipid composition are important to detect the impact of metals in these ecosystems.
Os sapais, considerados um dos ecossistemas mais produtivos, servem como reservatório para contaminantes, nomeadamente metais provenientes de industrias, reduzindo desta forma a contaminação dos ecossistemas circundantes. Em ambiente aquático, a poluição por mercúrio (Hg) é principalmente devido a descargas de efluentes de industrias contendo concentrações elevadas deste metal. O mercúrio é reconhecido como sendo um metal pesado e extremamente tóxico para as plantas, interferindo desta forma em vários processos celulares cruciais. Este estudo evidenciou a importância de compreender o processo aquando da exposição das plantas ao mercúrio e desta forma avaliar o impacto da toxicidade do Hg nas comunidades de sapais. Uma melhor compreensão sobre estes aspetos de acumulação avaliará o stress imposto pelo Hg sobre a produção primária em plantas de sapal e a adaptação das plantas no ecossistema. Adicionalmente este estudo permite também a interpretação dos mecanismos moleculares da tolerância ao mercúrio das plantas uma vez que estas são importantes para uma limpeza eficiente dos sistemas contaminados por Hg para uma restauração efetiva. Desta forma, o trabalho incidiu em duas espécies de plantas halófitas, Halimione portulacoides e Juncus maritimus recolhidas em dois locais da Ria de Aveiro contaminados por mercúrio, s1 considerado como o local menos contaminado e s2 como o local mais contaminado. Este estudo foi projetado para (1) avaliar como a distribuição de Hg em plantas (2) de que forma as plantas iram reter a toxicidade do Hg desencadeando respostas antioxidantes. De fato, a maioria dos parâmetros bioquímicos determinaram a evidência de respostas diferentes por concentrações diferentes de Hg no sedimento (s1 e s2) e (3) as plantas poderiam ou não modificar sua composição lipídica por toxicidade de Hg através da metodologia UPLC-MS. Este estudo demonstrou que ambas as espécies de plantas restringiam a absorção de Hg. No entanto, o processo foi mais eficiente em H. portulacoides. Foram observadas diferenças na quantidade de Hg acumulada por ambas as espécies. Os padrões de alocação também diferem entre as espécies. H. portulacoides apresentou diferentes níveis de Hg entre folhas, caules e raízes, enquanto J. maritimus acumulou os níveis mais elevados de Hg nas raízes. A conjugação dos processos, absorção e translocação resultou em concentrações semelhantes de Hg em caules e folhas e níveis de Hg muito elevados em raízes de J. maritimus. Os resultados obtidos demonstram que o Hg gerou danos oxidativos nas raízes de ambas as espécies e nas folhas de H. portulacoides. As diferenças na LPO entre espécies que se obteve refletem não apenas o nível de Hg acumulado e distribuição de Hg, mas também a capacidade de desencadear mecanismos de defesa. J. maritimus foi capaz de aumentar os níveis proteicos e atividade DHAR em raízes e rizomas e GSTs em rizomas. H. portulacoides não conseguiu induzir respostas enzimáticas antioxidantes. Contudo, nas folhas as moléculas antioxidantes como carotenoides e α-tocoferol foram aumentadas. No estudo do lipidoma, as espécies também apresentaram diferenças. Em H. portulacoides, os fosfolípidos diminuíram em todos os órgãos analisados, o que pode sugerir a alteração da permeabilidade da membrana. Além disso, os galactolípidos diminuíram a eficiência na fotossíntese. No entanto, o α-tocoferol aumentou, proporcionando assim uma melhor proteção às membranas de cloroplastos e manutenção da atividade fotossintética. Em J. maritimus, as alterações lipídicas só foram detetadas em raízes e rizomas, aumentando a permeabilidade lipídica e explicando a maior bioacumulação de concentrações elevadas de Hg. Os fito-esteróis diminuíram significativamente nas raízes e levaram a alterações da membrana de permeabilidade. O α-tocoferol diminuiu em ambos os órgãos de J. maritimus, demonstrando a ineficiência para a contaminação por Hg. Este estudo pode ser um ponto de partida para novos trabalhos, nomeadamente em outros sapais, em outras espécies e com outros metais. Compreender os mecanismos inerentes à tolerância de metais pesados em plantas de sapais e as mudanças na composição lipídica são importantes para detetar o impacto dos metais nestes ecossistemas.
Стилі APA, Harvard, Vancouver, ISO та ін.
18

Kohn, Wayne David. "Studies of electrostatic, salt, and metal-binding interactions in the Ã-helical coiled-coil, a model protein system." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ34790.pdf.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
19

Ahmed, Sohan. "Experimental Studies of Barite Growth Using Hydrothermal Atomic Force Microscopy in Alkali Metal Salt Solutions at 108 C." Wright State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=wright1567186567015893.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
20

Baur, Christian [Verfasser]. "Li-rich disordered rock salt transition metal oxyfluorides as novel cathode materials in lithium-ion batteries / Christian Baur." Ulm : Universität Ulm, 2020. http://d-nb.info/1219577693/34.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
21

Rashada, Yusef A. "The synthesis and characterization of chlorobutyl rubber-g-polyoxymethylene prepared via alkyl halide-metal salt initiated cationic graft copolymerization." DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 1987. http://digitalcommons.auctr.edu/dissertations/2709.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
22

Penso, Graciela Carolina. "Welding of X65 Internally Clad with Precipitation Strengthened Ni-Based SUperalloy Filler Metal: Application in Pre-Salt Oil Extraction." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1480600980467914.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
23

O'Reilly, Wiese Siobhan Bernadette. "An investigation into historical metal accumulation in the sediments of the Thames estuary and in two eroding Essex salt marshes." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362463.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
24

Lenoir, Isabelle. "Radical cascade reactions with isonitriles and dual lanthitide-transition metal catalysis : an approach to hidden diazoalkane and diazonium salt chemistry." Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343737.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
25

Iizuka, Masatoshi. "Studies on electrorefining and electroreduction processes for nuclear fuels in molten chloride systems." 京都大学 (Kyoto University), 2010. http://hdl.handle.net/2433/120864.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
26

Wilk, Gregory. "Liquid metal based high temperature concentrated solar power: Cost considerations." Thesis, Georgia Institute of Technology, 2016. http://hdl.handle.net/1853/54937.

Повний текст джерела
Анотація:
Current concentrated solar power plants (CSP) use molten salt at 565°C as a heat transfer and energy storage fluid. Due to thermal energy storage (TES), these solar plants can deliver dispatachable electricity to the grid; however, the levelized cost of electricity (LCOE) for these plants is 12-15 c/kWh, about 2.5 times as high as fossil fuel electricity generation. Molten salt technology limits peak operating temperatures to 565°C and a heat engine efficiency of 40%. Liquid metal (LM), however, can reach >1350°C, and potentially utilize a more efficient (60%) heat engine and realize cost reductions. A 1350 °C LM-CSP plant would require ceramic containment, inert atmosphere containment, additional solar flux concentration, and redesigned internal receiver. It was initially unclear if these changes and additions for LM-CSP were technically feasible and could lower the LCOE compared to LS-CSP. To answer this question, a LM-CSP plant was designed with the same thermal input as a published LS-CSP plant. A graphite internal cavity receiver with secondary concentration heated liquid Sn to 1400°C and transferred heat to a 2-phase Al-Si fluid for 9 hours of thermal energy storage. Input heat to the combined power cycle was 1350°C and had 60% thermal efficiency for a gross output of 168 MW. The cost of this LM-CSP was estimated by applying material cost factors to the designed geometry and scaling construction costs from published LS-CSP estimates. Furthermore, graphite was experimentally tested for reactivity with liquid Sn, successful reaction bonds, and successful mechanical seals. The result is switching to molten metal can reduce CSP costs by 30% and graphite pipes, valves, and seals are possible at least at 400°C.
Стилі APA, Harvard, Vancouver, ISO та ін.
27

O'Brien, Evan Daniel. "Welding with Low Alloy Steel Filler Metal of X65 Pipes Internally Clad with Alloy 625: Application in Pre-Salt Oil Extraction." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1469018389.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
28

Pattanayak, Soubhagya Kumar. "Role of external carbon and metal salt dosing in membrane bioreactor system to achieve limits of technology nutrient removal from municipal wastewater." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45672.

Повний текст джерела
Анотація:
Membrane bioreactor (MBR) technology in conjunction with conventional biological nutrient removal has been demonstrated to be successful in recent years. However, the limits of technology (LoT) effluent goal, ≤ 3 mg TN/L (total nitrogen) and ≤ 0.1 mg TP/L (total phosphorus), could potentially push a system to the limits of its capability. The broad objective of the long-term PhD study was to investigate role of external dosing of alum in a membrane biological nutrient removal (MBNR) system targeting LoT effluent nutrient levels. Two parallel MBNR systems, modified Bardenpho configuration, were operated under similar process conditions with metal salt addition being the only difference. The continuous flow MBNR system performance data signified the importance of external methanol and alum dosing in accomplishing the LoT nutrient removal goal. The stoichiometric methanol ratio, i.e. mg methanol required / mg NO₃-N removed, was calculated to be 6.1 in reducing average permeate NO₃-N concentration to 1.4 mg/L. Similarly, an average molar Al/TP ratio of 1.9 was required to reduce PO₄-P concentration to 0.07 mg/L in the permeate. Chemical phosphorus removal did not have any influence on COD removal, nitrification (except for a brief period) and denitrification. The relationship between chemical P removal and enhanced biological phosphorus removal (EBPR) was dynamic and was dependent on alum dosage concentration. At high dosage levels (i.e. 80 mg/L), alum supplementation competed with and finally, inhibited EBPR until the MBNR system was converted to a chemical P removal system. Activated sludge modeling was undertaken to analyze its suitability in predicting the performance of an MBNR system targeting LoT goals. The model was successful in predicting nitrogen removal, while parameter calibration was required for fitting of the measured suspended solids and EBPR data. Moreover, the model could not predict the relationship between the simultaneous biological and chemical P removal accurately. A direct batch DON measurement method, batch anion exchange resin adsorption followed by persulfate digestion, was developed and validated successfully. Using the method, the DON contribution to permeate total nitrogen was observed to vary from 7 percent to 96 percent in the parallel MBNR systems, when permeate TN concentrations were less than 3 mg/L.
Стилі APA, Harvard, Vancouver, ISO та ін.
29

Beereddy, Dinesh Reddy. "Waste Water Treatment and Optimal Utilization for Irrigation and Biogas Production." Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-171842.

Повний текст джерела
Анотація:
This paper is about the studies carried out to analyze the feasibility of using an innovative treatment system in the primary treatment process for municipal waste water. Furthermore, experiments are conducted to analyze the optimal parameters for utilizing the treated waters for irrigation purposes and for biogas production from the recovered sludge. The work is carried on the incoming municipal wastewater from Hammarby locality with around 30,000 inhabitants. Chemicals used in this process are, a metal salt namely polymerized aluminum chloride (PAX XL36) and two flocculation chemicals namely, a high molecular weight polymer (HM) (SNF Nordfloc C-192) and a low molecular weight polymer (LM) (Purfix 120). The choice of these chemicals was based on the recommendations made by previous studies on flocculation chemicals. These chemicals aid in flock formation and the DAF unit which provides compressed air, aids in flock flotation. The study is focused on optimizing parameters which implies minimal usage of chemicals and aimed to attain maximum sludge production with best possible treated water quality. All the experiments have been carried out on a pilot scale unit, designed with required specifications and with the foresight to scale up into a large scale unit based on the results. These are obtained by performing a series of analysis specifically formulated for this study. In laboratory experiments were carried out to analyze COD (chemical oxygen demand), Ammonium, Nitrate, Total nitrogen and phosphorus using Dr. Lange cuvettes. As the prime focus is on reuse of the treated water for irrigation purpose and biogas production, all the parameters are modulated in accordance with the standard water quality prescriptions for the water to be used for irrigation. In accordance with the climatic conditions of the region, various parameters are modulated in such a way that in summers the outcome water quality is emphasized and maximization of sludge/organic matter is emphasized during winter season.
Стилі APA, Harvard, Vancouver, ISO та ін.
30

Afraz, Syed Ali. "Mechanical, Microstructural and Corrosion performance for MIM materials based on coarse (-45µm) powders of ferritic stainless steel." Thesis, KTH, Materialvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-127680.

Повний текст джерела
Анотація:
The purpose of this research is to investigate the mechanical, microstructural and corrosion performance of the ferritic stainless steel coarse powders, used in Metal Injection Molding (MIM) process. Three coarser powders made by Höganäs AB, were examined along with a commercially available fine MIM powder and samples from sheet metal. The studied powders were individually mixed with binders and then injection molded in the shape of dog bone shaped tensile bars. These green samples were then debinded and sintered to examine under different characterization methods. The methods used for examining the samples were tensile test, hardness test, metallography, SEM, chemical analysis, and salt spray test. After a comparative study of these different materials, it turns out that the chemical composition and the process parameters have more effect on materials properties compared to only particle size distribution in studied materials. After this study, 434 coarse powder was preferred upon the PolyMIM 430 fine powder, because of its lower price and same performance as that of PolyMIM 430.
Стилі APA, Harvard, Vancouver, ISO та ін.
31

Sui, Yongkun. "A Low-Temperature Printing Technology for Fabricating Electrically Conductive Structures and Devices Using Plasma-Activated Stabilizer-Free Inks." Case Western Reserve University School of Graduate Studies / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=case1562589709669126.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
32

Clegg, Yolanda. "Historical inventory of sedimentary carbon and metals in a Bay of Fundy salt marsh." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=30357.

Повний текст джерела
Анотація:
In 1996, four cores (∼30 cm depth) were extracted from the high marsh zone of Dipper Harbour salt marsh in the Bay of Fundy. Soil bulk densities are shown to be controlled by mineral density and are higher than those reported for salt marshes in the northeastern United States. Examination of variations in mineral content suggests that regular tidal action and ice rafting deposits the majority of the mineral sediment to the high marsh zone. Dating techniques (based upon pollen, 137Cs, 210Pb and total Pb) were applied to selected cores, suggesting accretion rates from 0.25 to 0.31 cm yr-1 which are higher than the rates of local relative sea level rise. Correlation of trace metal densities (Cu, Fe, Pb and Zn) to Al densities were used to justify Al normalization. After consideration of natural sources and adsorption factors, the normalized Pb profiles are shown to reflect historical pollution levels of leaded gasoline consumption. Carbon storage values in the upper 25 cm of sediment range from 7.3--10.5 kg C m-2 and carbon accumulation rates vary from 95 to 124 g C m-2 yr-1, representing 15--29% of the salt marsh macrophyte productivity.
Стилі APA, Harvard, Vancouver, ISO та ін.
33

Godsell, A. J. "Fused salt electrorefining of ferroalloys." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254069.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
34

Аларкон, К. М., Тетяна Василівна Диченко, Татьяна Васильевна Дыченко та Tetiana Vasylivna Dychenko. "Роль металлов в живых организмах". Thesis, Сумский государственный университет, 2015. http://essuir.sumdu.edu.ua/handle/123456789/39749.

Повний текст джерела
Анотація:
Большое число важнейших стадий процессов жизнедеятельности контролируется содержащимися в тканях организма ионами металлов. Нарушения в строгом режиме работы систем, содержащих металлы, тяжело сказываются на общем состоянии организма. Зная, какова роль того или иного металла, можно бороться с болезненными, патологическими явлениями и успешно ликвидировать их.
Стилі APA, Harvard, Vancouver, ISO та ін.
35

Copham, Piers Martin. "Rotating electrodes in molten salt electrowinning." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.330202.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
36

晃宏, 湯川, та Akihiro Yukawa. "溶融塩電気化学プロセスによる緻密質炭素膜の形成". Thesis, https://doors.doshisha.ac.jp/opac/opac_link/bibid/BB12905947/?lang=0, 2014. https://doors.doshisha.ac.jp/opac/opac_link/bibid/BB12905947/?lang=0.

Повний текст джерела
Анотація:
本研究では比較的安価な設備を用い、低温で量産性のある炭素膜を得ることが出来る溶融塩電気化学プロセスに着目し、電解条件が炭素膜に及ぼす影響、浴温が炭素膜に及ぼす影響、基材前処理における酸活性が炭素膜と基材の密着性に及ぼす影響等を明らかにしたものである。
博士(工学)
Doctor of Philosophy in Engineering
同志社大学
Doshisha University
Стилі APA, Harvard, Vancouver, ISO та ін.
37

Zhao, Weijie. "Corrosion initiation induced by sodium sulfate and sodium chloride particles on Cu and the golden alloy Cu5Al5Zn at simulated atmospheric conditions." Thesis, KTH, Materialvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-219471.

Повний текст джерела
Анотація:
Effects of sodium sulfate (Na2SO4) particle deposition on the atmospheric corrosion of copper (Cu) metal and a Cu-based alloy (Cu5Al5Zn) used in architectural applications were investigated at laboratory conditions compared with effects induced by sodium chloride (NaCl) and to some extent ammonium sulfate (NH4)2SO4 induced corrosion. Pre-deposited surfaces were exposed to repeated wet/dry conditions in a climatic chamber and the formation of corrosion products were assessed using light optical microscopy (LOM), scanning electron microscopy with elemental analysis (SEM/EDS), Fourier transform infrared techniques (FTIR microscopy) and cathodic reduction (CR). Na2SO4 induced corrosion resulted in corrosion cells locally over the surface on both Cu and Cu5Al5Zn, of increased oxygen content in the anodic area of the cells (center of pre-deposited area). The main corrosion products formed on Cu metal are basic copper sulfates and cuprite (Cu2O), while basic sulfates (copper and/or zinc) and Cu2O were the main corrosion products formed on Cu5Al5Zn. A combined deposition of Na2SO4 + NaCl was carried out on the Cu5Al5Zn alloy using two different deposition methods to investigate the possible interplay from a corrosion initiation perspective between the two salt particles. For short time exposed Cu5Al5Zn (1 cycle), two different corrosion cells formed, mainly induced by Na2SO4 and NaCl. Corrosion products formed in anodic areas of a Na2SO4 induced corrosion cell were similar to findings observed for Cu5Al5Zn pre-deposited with Na2SO4 only, whereas peripheral cathodic areas primarily were affected by NaCl dissolution and predominantly composed of Cu2O that was the main corrosion product with small amount of hydroxides and carbonates of the NaCl induced corrosion cells. After relatively longer exposure periods (2 and 6 wet/dry cycles), NaCl dominated the corrosion of the entire surface with the formation of more Cu2O, hydroxides and carbonates. Cathodic reduction findings revealed a negative interplay on corrosion for the mixed salt after short time exposures (1 and 2 cycles), whereas a slight synergistic effect was evident after a longer exposure period (6 cycles), compared with corrosion induced by single salts.
Стилі APA, Harvard, Vancouver, ISO та ін.
38

Thomas, Jaron Michael. "On Metal synthesis of Some Substituted Rhenium and Manganese Complexes." TopSCHOLAR®, 2012. http://digitalcommons.wku.edu/theses/1225.

Повний текст джерела
Анотація:
Heterocyclic organic and organometallic compounds (i.e. polypyrrole), and their derivatives, have been of great interest for conductive polymers due to their novel properties and environmental stability as compared to their non-aromatic analogs (i.e. polyacetylene). Our current interest focus upon the potential role of metal ligand bound pyridazines as the next generation of electronic devices that utilize the metal ligands bound to organics as the semiconducting material. Pyridazine is a 6-membered aromatic ring with two adjacent nitrogen atoms. These are promising candidates for a variety of materials and commercial applications; but they are difficult to get a metal ligand to fuse to the aromatic ring. Our recent efforts focused in attaching Rhenium and Manganese ligands/substituents (process in which is called doping) that would cause oxidation to occur to our polymer making it a p-type polymer. Since p-type polymers charge carriers leave a vacancy that does not delocalize completely. This vacancy (known as a hole) or a radical cation that only partially delocalizes over several monomeric units causing them to be structurally deformed. This deformed structure is at a higher energy than that of an undoped polymer. Typical carriers in organic semiconductors are holes and electrons in a π-orbital. So when these molecules of π-conjugated systems have a π-bond overlap (or π- stacking), electrons can move via these π-electron clouds overlapping thus causing an electrical current. Our worked focused on the synthesis of pyridazines and their organometallic rhenium complexes and polymer research. Several aryl-substituted 5,6-fused pyridazines have been synthesized but none have been documented until this study. The main goal of the research was to fully characterize the general synthesis of furan containing organometallic complexes, [M(CO)3{η5-1,2-C5H3(CC4H3ON)(CC4H3ON)}] (M = Re or Mn) (4B). We successfully characterized the ability to attach a metal organic ligand to pyridazine though IR and NMR. However, when attempts were made to recrystallize our product, we yielded an orange-brown, block like crystal of 1,2- C5H3(CC4H3ONH)(CC4H3ON) (5) in which our metal ligand group fell off and we were left with pyridazine and inorganics. Though, we successfully got an X-ray characterization and electronic studies of compound 5 which are reported herein.
Стилі APA, Harvard, Vancouver, ISO та ін.
39

Kurakin, Yuriy. "Vliv vybraných činidel na krystalizační schopnost polylaktidu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-433111.

Повний текст джерела
Анотація:
The influence of seven additives on the crystallization ability of polylactide (PLA), melt flow index (MVR) and mechanical tensile properties was studied. Pressed plates with a thickness of 0.8 mm were tested. Selected additives added in amounts of 0.5 and 1.0% were as follows: talc, sodium benzoate, mixtures of organic salts with amorphous SiO2 and zinc stearate, metal salt, phosphate salt, and potassium salt of 5-dimethylsulfoisophthalate (LAK-301 - nucleating agent developed for PLA). Non-isothermal crystallization measurements were performed at different cooling rates (0.3; 0.5; 0.7; 1.0 and 1.5 ° C). All nucleation agents increased the MVR of PLA except talc; the largest increase (9-fold and 24-fold) was the addition of metal salt. The additives did not fundamentally change the mechanical properties. All samples were rather brittle (the most brittle with LAK-301), the modulus of elasticity was around 1.2 GPa for all samples, the strength of PLA was increased the most by the addition of 1% talc (by 12%) and the elongation at break was increased by organic salt with SiO2. All samples with nucleating agents content of 1% were amorphous (crystalline content did not exceed 2%). Thus, the addition of reagents did not support the crystallization process during rapid cooling, even in the case of LAK-301. However, LAK-301 was acting as an excellent nucleating agent at slow cooling rates (1.5 °C / min and below). The nucleation activity of the additives decreased in the following order: LAK-301, organic salt with zinc stearate, talc, organic salt modified with amorphous SiO2 and phosphate salt. Samples with sodium benzoate and metal salt were crystallizing on cooling in several steps and it was not possible to use the method of Dobrev and Gutzow to evaluate the nucleation activity.
Стилі APA, Harvard, Vancouver, ISO та ін.
40

Mottot, Yves. "Propriétés chimiques et électrochimiques des chlorures de lanthanides cérides en milieux chlorures fondus : stabilité thermodynamique des alliages LA-NI et ND-FE à haute température." Paris 6, 1986. http://www.theses.fr/1986PA066127.

Повний текст джерела
Анотація:
Etude thermodynamique et cinétique de la réduction électrolytique de terres rares cériques, réalisée au sein de l'eutectique fondu LICL-KCL. Comportement singulier du néodyme étudié dans l'eutectique BACL::(2)-KCL jusqu'à 1300k; on montre que la stabilité de ND(II) croit avec la température. Etude des alliages entre les métaux des terres rares et les métaux de transition de composition générale LNM::(X), dont les propriétés thermodynamiques ont été déterminées par mesure de la F. E. M. De la pile LN/LNCL::(3), LICL+KCL/LNM::(X); application aux alliages LA-NI ET ND-FE entre 700 et 800K.
Стилі APA, Harvard, Vancouver, ISO та ін.
41

Bousedra, Harrag. "Codeposition electrolytique de zinc et de cadmium sur acier doux : resistance a la corrosion." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13109.

Повний текст джерела
Анотація:
Analyses et etudes de la structure des revetements obtenus par co-deposition electrolytique de zinc et de cadnium sur des aciders bas carbone. Etude de la resistance a la corrosion en brouillard salin des depots et de l'influence de leur composition
Стилі APA, Harvard, Vancouver, ISO та ін.
42

Schofield, Paula. "A study of poly(ethylene oxide) blends and copolymers in the presence of alkali metal salts." Thesis, University of Liverpool, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260318.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
43

Henry, Marc. "Application du concept d'electronegativite aux processus d'hydrolyse et de condensation en chimie minerale." Paris 6, 1988. http://www.theses.fr/1988PA066293.

Повний текст джерела
Анотація:
Utilisation des procedes sol-gel pour elabour des materiaux a base d'oxydes et a proprietes optimisees. Mecanismes d'hydrolyse et de condensation des precurseurs moleculaires (alcoxydes ou sels metalliques) aboutissant a l'obtention de materiaux mixtes organiques/inorganiques
Стилі APA, Harvard, Vancouver, ISO та ін.
44

Röman, Simon, and Marielle Krus. "Kodade Kläder : Spårbarhet genom forensisk märkning inom textilindustrin med fokus på sorteringsprocessen." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-12384.

Повний текст джерела
Анотація:
Textilindustrins miljöpåverkan är hög, samtidigt som efterfrågan på textilfibrer ständigt ökar. Inom de kommande åren förväntas textilåtervinningen i Sverige att öka vilket skulle skapa en mer cirkulär resursanvändning som på så sätt kan minska tillverkningen av jungfruliga fibrer. För att återvinningsprocessen för de förbru- kade textilierna ska fungera optimalt krävs en sorteringsmetod med hög säkerhet i materialurskiljning. Inom kriminaltekniska områden används märkvätskor för att märka upp värdefulla föremål. Märkvätskorna baserade på metallsalter skapar unika sifferkoder som kan avläsas med en laserteknik kallad LA-ICP-MS. Om ett märkt föremål blir stulet och sedan återfinns av polisen kan märkvätskan avläsas och kopplas tillbaka till ägaren via en databas. Genom att applicera den osynliga forensiska märkvätskan på textilier var projektets förhoppning att skapa spårbarhet i det textila ledet med fo- kus på att underlätta sorteringsprocessen i återvinningsstadiet. Detta genom att skapa en säker märkning som sitter kvar under textilens hela användarfas. Märk- vätskan som användes i projektet kom från SmartWater Technology Ltd som är det ledande företaget i England inom forensiska märkningar. För att simulera en användarfas för ett bomullsplagg har testmetoder för färghär- dighet mot tvätt samt nötningshärdighet utförts. En extern analys utfördes på Smar- tWaters laboratorium i Telford, England, för att kontrollera om koderna gick att avläsa efter de utförda testerna. Testmetoderna har utförts utefter antagandet att metallkoderna har bättre härdighet än den fluoroscensiska färgen. Vid slitage inne- bär detta att färgen avlägsnas vid ett tidigare skede än metallsalterna, vilket resulte- rar i att kodens placering blir omöjlig att hitta utan dess färg. Under detta projekt har därför den fluoroscensiska färghärdigheten varit i fokus. Resultatet som erhölls från nötnings- och tvätthärdighetstestet analyserades under UV-ljus i ljusskåp genom att jämföra färgförändringen mot ett referensprov. En 5- gradig grå-grå-skala användes för att omvandla färgavvikelsen till numeriska vär- den, vartefter matematiska beräkningar utfördes för att kontrollera statistisk signi- fikans. Studien visade att märkvätskans fluoroscensiska färg försämras i takt med antal tvättar. Färgen försämrades något i jämförelse med referensprovet efter nöt- ning, men ingen signifikant skillnad kunde utläsas mellan provkropparna efter ökat antal varv i Martindalemaskinen. Analysen genom LA-ICP-MS kopplade samtliga provkroppar till korrekt applicerad kod vilket tyder på en säker avläsningsteknik. Baserat på tidigare nämnda resultat förväntas märkvätskan därför klara av en an- vändarfas för exempelvis ett ytterplagg eller en möbel i bomull. Fler tester krävs dock för att säkerhetsställa hur vätskan håller efter tid och ytterligare antal tvättar. Lasertekniken som användes för att avläsa koden är säker, men behöver utvecklas eller bytas ut för att en snabbare sorteringsprocess ska erhållas.
The environmental impact for the textile industry is already high and with an in- creasing demand for textile fibers something has to change within the industry. The textile recycling in Sweden is expected to increase in the coming years, which would create a more circular resource utilization, thus reducing the production of virgin fibers. In order to create an optimal recycling process, a secure sorting method is required in material separation. To be able to track valuable objects within the forensic area, a compound based on metal salts is used to mark the objects. The metal composition can be translated into a specific and unique code with a laser method called LA-ICP-MS. The code can later be connected to a person or an organization registered within a database. This thesis examines the possibility to apply the forensic marking compound on a textile carrier to create a trustworthy traceability within the textile chain that is difficult to remove. Instead of register a person or an organization to a code, the vision was to connect a code to a material or a chemical content within the textile product. The forensic marking system used in this thesis came from SmartWater Technology Ltd, which is the leading company in England within forensic coding. A quantitative study was made to research how the forensic coding system based on metal salts acted on a textile carrier. The researched problem was based to ana- lyze the suitability to use a forensic marker system on a textile carrier with the aim to create traceability within the textile industry and to ease the sorting process. To be able to investigate the problem a simulated phase of use was made. Test methods were performed to analyze the impact of abrasion and the ability to with- stand washing for the forensic marking. An external analysis was made at Smart- Waters laboratory in Telford, England, to examine if the metal salts were de- codable, even when the forensic marking was in a bad condition. All the tests and analysis was made with the supposition that the metal salt coding had a better ad- hesion to the carrier than the fluorescence color. Since the coded area cannot be found without the color, the results have been based on the change in color of the fluorescence marking solution. The conclusion shows that the fluorescence colorfastness was decreasing with the number of washing cycles. Number of cycles in Martindale was not significant for a decrease in colorfastness. The LA-ICP-MS method was able to decode all of the samples and connect them to the applied codes. This indicates that the forensic marking system is durable and can be used to mark a garment or a piece of furni- ture that’s not washed a lot. However, more tests are required to ensure how the solution lasts over time and additional amounts of laundry. The LA-ICP-MC meth- od is secure, but one problem is that it’s stationary and therefore difficult to use in a sorting process.
Стилі APA, Harvard, Vancouver, ISO та ін.
45

Martinez, Aguilar Maricelly. "Production de biobutanol à partir de lignocellulose : un nouveau procédé thermochimique A simple process for the production of fuel additives using residual lignocellulosic biomass Production of fuel additives by direct conversion of softwood bark using a cheap metal salt Conversion of lignocellulosic biomass in biobutanol by a novel thermal process." Thesis, Ecole nationale des Mines d'Albi-Carmaux, 2020. http://www.theses.fr/2020EMAC0006.

Повний текст джерела
Анотація:
La demande d'énergie au cours des dernières années a augmenté et un grand pourcentage de l'énergie est dérivée des combustibles fossiles, mais l'utilisation de ces carburants a généré des émissions de CO2 et de la pollution environnementale. Pour ce problème, on a mené des recherches sur l'utilisation des énergies alternatives à partir de biomasse lignocellulosique pour produire des carburants qui réduisent les émissions de CO2. Le Canada est un pays avec une abondance de résidus lignocellulosiques qui sont une source pour la production de différents produits chimiques. La première partie de l’étude se concentre sur l’étude cinétique de la production du lévulinate de méthyle et de l’acide lévulinique à partir de la cellulose avec un catalyseur homogène (H2SO4). La deuxième partie porte sur la conversion de la cellulose en lévulinates (molécule plateforme) en utilisant un catalyseur homogène (H2SO4) et un catalyseur solide (Al2(SO4)3). La troisième partie se consacre sur l’étude de l’hydrolyse du lévulinate de méthyle en acide lévulinique en utilisant des catalyseurs à base de cuivre. Des techniques d’analyse tels que le SEM, XRD, TPX ont été utilisés pour étudier les catalyseurs supportés et comprendre leur effet sur la réaction. La quatrième partie du projet porte sur l’étude des résultats obtenus des différentes réactions réalisées pour la production du 2-butanol à partir de la biomasse lignocellulosique en passant par la production du lévulinate de méthyle et de l’acide lévulinique qui sont des molécules plateforme et potentiellement substitutes au biodiesel. Par la suite, l’acide lévulinique est décarboxylé en 2-butanone et le dernier est réduit en 2-butanol en utilisant des catalyseurs bifonctionnels (tels que le Ru / C et le Pt / C) en conditions douces. L’ensemble de ces travaux contribuent à la compréhension des réactions du nouveau procédé de production du butanol
In the last years, the energy demand has increased and a large pourcentage of this energy is obtained from fossil fuels, but the use of these fuels has generated CO2 emissions and environmental pollution. For this reason, this research was focused on the use of alternative energies from lignocellulosic biomass to produce renewal fuels decreasing CO2 gas emissions. Canada is a country with high quantities of lignocellulosic biomass which can represent a cheap source for the high value added molecules and fuels production. The first part of the study focuses on the kinetic study of the production of methyl levulinate and levulinic acid from cellulose with a homogeneous catalyst (H2SO4). The second part study the conversion of cellulose to levulinates (platform molecule) using a homogeneous catalyst and a heterogeneous catalyst (Al2(SO4)3). The third part is devoted to study the hydrolysis of methyl levulinate to levulinic acid using copper-based catalysts. Analytical techniques such as SEM, XRD, TPX were used to study the supported catalysts and understand their effect on the reaction. The fourth part of the project relates to the study of the production of 2-butanol from lignocellulosic biomass through the production of methyl levulinate and levulinic acid which are platform molecules and potentially substitutes for biodiesel. Thereafter, the levulinic acid is decarboxylated to 2-butanone and the latter is reduced to 2-butanol using bifunctional catalysts (such as Ru/C and Pt/C) under mild conditions. All of this work contributes to understanding the reactions of the new butanol production process
Стилі APA, Harvard, Vancouver, ISO та ін.
46

Norikawa, Yutaro. "Electrodeposition of Titanium Metal from Fluoride–Chloride Mixed Molten Salts Consisting of Single Cations." Kyoto University, 2020. http://hdl.handle.net/2433/253387.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
47

Tang, Yiteng. "Exciton Physics of Colloidal Nanostructures and Metal Oxides." Bowling Green State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1617121207654824.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
48

Abied, Hamid. "Etudes structurales des phases cristalline et colomnaire de cuivre." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13065.

Повний текст джерела
Анотація:
Caracterisation du polymorphisme liquide cristallin thermotrope des savons de cuivre divalent. Description de la structure des phases liquides cristallines rencontrees a haute temperature et de la phase cristalline observee a temperature ordinaire. Etude approfondie de la distribution des atomes metalliques a l'interieur des colonnes de la structure en colonnes
Стилі APA, Harvard, Vancouver, ISO та ін.
49

Hmimid, Noureddine. "Etude structurale de nouveaux diphosphonates." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37598321s.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
50

Cooper, Jeffery W. "Spectrophotometry of rare earth chloride and fluoride complexes in molten salt solutions using a remote high temperature sensor /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p3137687.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Ми пропонуємо знижки на всі преміум-плани для авторів, чиї праці увійшли до тематичних добірок літератури. Зв'яжіться з нами, щоб отримати унікальний промокод!

До бібліографії