This study focused on molten salt purification processes to effectively reduce or eliminate the corrosive contaminants without altering the salt's chemistry and properties. The impurity-driven corrosion behavior of HAYNES® 230® alloy in the molten KCl-MgCl2-NaCl salt was studied at 800 ºC for 100 hours with different salt purity conditions. The H230 alloy exhibited better corrosion resistance in the salt with lower concentration of impurities. Furthermore, it was also found that the contaminants along with salt's own vaporization at high temperatures severely corroded even the non-wetted surface of the alloy. The presence of Mg in its metal form in the salt resulted in an even higher mass-loss possibly due to Mg-Ni interaction. The study also investigated the corrosion characteristics of several nickel and ferrous-based alloys in the molten KCl-MgCl2-NaCl salt. The average mass-loss was in the increasing order of C276 < SS316L < 709-RBB* < IN718 < H230 < 709-RBB < 709-4B2. The corrosion process was driven by the outward diffusion of chromium. However, other factors such as the microstructure of the alloy i.e. its manufacturing, refining, and heat-treatment processes have also shown to influence the corrosion process. Lowering the Cr content and introducing W and Mo in the alloy increased its resistance to corrosion but their non-uniform distribution in the alloy restricted its usefulness. To slow-down the corrosion process, and enhance the material properties, selected alloys were boronized and tested for their compatibility in the molten KCl-MgCl2-NaCl salt. The borided alloys exhibited better resistance to molten salt attack, where the boride layer in the exposed alloy was still intact, non-porous, and strongly adhered to the substrate. The alloys also did not show any compensation in their properties (hardness). It was also found that the boride layer always composed of an outermost silicide composite layer, which is also the weakest and undesired layer as it easily cracks, breaks, or depletes under mechanical and thermal stresses. Various different grades of "virgin" nuclear graphites were also tested in the molten KF-UF4-NaF salt to assist in the selection of tolerable or impermeable graphites for the MSR operational purposes. It was found that molten salt wettability with graphite was poor but it still infiltrated at higher pressure. Additionally, the infiltration also depended on the pore-size and porosity of the graphite. The graphite also showed severe degradation or disintegration of its structure because of induced stresses. / Doctor of Philosophy / Molten salts are considered as potential fuel and coolant candidates in MSRs because of their desirable thermophysical properties and heat-transfer capabilities. However, they pose grave challenges in material selection due to their corrosive nature, which is attributed to the impurities and their concentration (mostly moisture and oxygen-based) in the salt. This study focused on purifying the salt to reduce these contaminants without compromising its composition and properties. The influence of purification processes on the corrosion behavior of HAYNES® 230® alloy was studied in the molten chloride salt with different purity conditions. Various nickel and ferrous-based alloys were also studied for their compatibility in the molten chloride salt. This will assist in expediting the material selection process for various molten salt applications. It was observed that several factors such as alloy composition, its microstructure, impurities in the salt attribute to molten salt corrosion. It was also quite evident that corrosion in molten salts is inevitable and hence, the focus was shifted on slowing down this process by providing protective barriers in the form of coatings (i.e. boronization). The borided (coated) alloys not only improved the corrosion resistance but also enhanced and retained their properties like hardness after exposure to molten salts. Since these studies were conducted under static conditions, a more detailed investigation is needed for the selected alloys by subjecting them to extreme flow-conditions and for longer a duration of time. To achieve this objective, a forced circulation molten salt loop was designed and fabricated to conduct flow corrosion studies for alloys in molten chloride salt. Graphite is another critical component of the MSR where it is used as a moderator or reflector. Generally, molten salts exhibit poor wettability with graphite, but they can still infiltrate (graphites) at higher applied pressures, and result in the degradation or disintegration of graphite's structure, and eventually its failure in the reactor. This study provides infiltration data, and understanding of the degradation of various 'virgin' nuclear graphite grades by the molten fluoride salt. This should assist in the selection of tolerable or impermeable graphite grades for MSR operational purposes.

京都大学 / 新制・論文博士 / 博士(理学) / 乙第13577号 / 論理博第1579号 / 新制||理||1713(附属図書館) / 京都大学大学院理学研究科生物科学専攻（霊長類学・野生動物系） / (主査)教授 松田 一希, 教授 平田 聡, 准教授 杉浦 秀樹 / 学位規則第4条第2項該当 / Doctor of Science / Kyoto University / DFAM

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Thesis (MBA)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Changes in the global salt market have presented Walvis Bay Salt Refiners with an opportunity to increase its current sales by approximately 40%. Following several pre-feasibility studies, the expansion project plan was created. The construction of new ponds, canals and sluices were to be performed by a subcontractor as selected through a tender process. The scope of the work comprised approximately 70% of the total project cost and it also represented the most critical part of the expansion project. Thomas Saaty’s Analytic Hierarchy Process, was used as a group decision support system for the selection of the most suitable subcontractor. The weighted average mean method was used to aggregate individual scores. A sensitivity analysis was performed following the final outcome to gain a deeper understanding of the problem, obtain a measure of margin between subcontractor scores and to check for the correctness of numbers. / AFRIKAANSE OPSOMMING: Veranderinge in die wêreld soutmark het vir Walvis Bay Salt Refiners 'n geleentheid gebied om sy verkope met ʼn beraamde 40% te verhoog. Na verskeie voorondersoeke is 'n volledige projekplan opgestel. Die vervaardiging van damwalle, kanale en sluise sou deur 'n kontrakteur gedoen word wat deur ʼn tenderprosedure gekeur sou word. Die omvang van hierdie gedeelte van die uitbreidingsprojek verteenwoordig ongeveer 70% van die totale projekkostes en is terselfdelyk die mees sensitiewe gedeelte van die projek. Thomas Saaty se Analytic Hierarchy Process is gebruik as die groepbesluitnemingsondersteuningstelsel om die mees geskikte kontrakteur te kies. Die geweegde gemiddelde is gebruik om die individuele oordele saam te voeg. Sensitiwiteits analise is uitgevoer nadat die finale uitslag bepaal is om sodoende beter insig in die probleem te ontwikkel, om ʼn beter onderskeiding tussen die kontrakteur puntetellings te kry en om die juistheid van die syfers na te gaan.

This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project. / Preface by G. E. P. Smith

The goal of this thesis was to map historical progress of disarmament agreements between Russian Federation and The United States of America from the end of the World War II, through the Cold War and ending in the present, formulated by the latest agreement NEW START made in 2010. This period of time includes rounds of negotiations about SALT, SALT II, INF agreement, through START I, START II, which never came in effect, ending with NEW START. Thesis is analyzing agreements not only via itself agreement's lines or proposals but also with their negotiations that led to formation of the agreements including brief historical background in which they were formatted. Rather bigger attention in this thesis is dedicated to the NEW START agreement which gained experience from past agreements. Thesis is divided into 5 chapters where the first chapter is dealing with theoretical delimits of terms which are necessary for sufficient understanding of the textual mater of these agreements. Other chapters are designed so that after every short introduction of the historical background is following analysis of the agreements or their particular links and their comparison with the previous agreements. Last chapter is focused on the issues about controlling the fulfillments of the agreements under the agreements...

[Truncated abstract] Lophopyrum elongatum, a wild relative of wheat, can be used as a source of novel genes for improving the salt tolerance of bread wheat. Na+ `exclusion? is a major physiological mechanism for salt tolerance in the wheat L. elongatum amphiploid, and a large proportion (~50%) of the improved Na+ `exclusion? is contributed by a gene(s) on chromosome 3E. This study integrated physiological analysis with comparative genomics to identify gene orthologues that may regulate Na+ transport, and designed and implemented molecular markers for developing wheat L. elongatum recombinant lines with reduced portions of L. elongatum chromatin retaining the Na+ `exclusion? trait. Physiological analysis of leaf Na+ accumulation in wheat L. elongatum substitution lines confirmed that the 3E chromosome contributes a major effect on reduced leaf Na+ accumulation in wheat when grown at 200 mM NaCl. Candidate genes from the model plant, Arabidopsis thaliana, controlling Na+ transport into and from cells (SOS1, HKT1) or compartmentalisation within vacuoles (NHX1, NHX5, AVP1, AVP2) were targeted for comparative analysis in wheat. Wheat gene orthologues were identified by BLAST searching to identify either FL-cDNAs or ESTs, which were subsequently used to amplify genomic DNA, and orthologues confirmed by similar intron-exon structure between Arabidopsis and rice. Intron-exon comparisons showed the majority of exons were conserved between Arabidopsis, rice and wheat, but also indicated exon shuffling events since divergence from a common ancestor. Gene orthologues were assigned to homoeologous chromosomes and non-syntenic regions between wheat and L. elongatum, with the SOS1 orthologue located on group 3 chromosomes in wheat and L. elongatum. ... The recombinant line 524-568 contains a small introgression on the distal end of the long arm of wheat chromosome 3A and represents the most desirable line presently available for further germplasm development. The main outcomes of this thesis have been an increased understanding of the physiology and evolution of orthologues for Na+ transport in wheat and L. elongatum, improved methodologies for designing alien-specific PCR markers, and the development of overlapping recombinant lines that provide a source of novel genes for pyramiding into wheat and improving its tolerance to salt stress.

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xiii, 248 p. : ill. A print copy of this title is available through the UO Libraries under the call number: KNIGHT E98.P8 D43 1992 / The current interpretation of post-Archaic culture history in the northeastern Great Basin is that the Great Salt Lake regional variant of the Fremont culture arose from an Archaic base and is distinguished by two types of unpainted pottery, Great Salt Lake Gray and Promontory Gray. Seen as ethnically unrelated to the Fremont, the subsequent Shoshoni culture is marked by one type of unpainted pottery, Shoshoni Ware. These types are said to be characterized by distinct combinations of attributes, but close examination reveals that what these combinations are, and how they distinguish each type, has not been clearly described in the archeological literature. In this study, I re-analyze fragments of undecorated pottery previously classified as Great Salt Lake Gray, Promontory Gray, and Shoshoni Ware. Through rigorous and replicable methods, five major attributes found in every sherd are examined: wall thickness, exterior surface color, temper material, temper size, and technique of vessel shaping. This analysis showed that previous identifications of pottery attributes were partially or entirely erroneous. Every attribute measured demonstrated the same essential pattern: Great Salt Lake Gray had a wide range of variation, and Promontory Gray and Shoshoni Ware fell within this range. Further, except for one form of temper material, Promontory Gray and Shoshoni Ware shared the same attributes with one another. Ethnographic evidence is also presented that links late prehistoric pottery to that of the historic Shoshoni, confirming a single unbroken pottery tradition in the Great Salt Lake region. I conclude that the evidence of this study does not support the concept of two unrelated pottery traditions (Fremont and Shoshoni) in the Great Salt Lake region. Based on this work, much of the traditionally conceived post-Archaic culture history of this region must be reevaluated.