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Black, Ann Marie. « A Model for Estimating Available Iron from Total Nutrient Intakes ». DigitalCommons@USU, 1986. https://digitalcommons.usu.edu/etd/5328.
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Factors which affect iron bioavailability have been repeatedly and extensively investigated. A model, derived from these studies, has been developed for estimating available iron from meal data. However, many dietary surveys report only average daily intakes of iron, and do not report the iron present in single meals. No model to estimate available iron from daily iron intake has been presented in the literature.
Dietary questionnaires were kept for two nonconsecutive weekdays by 355 male and 382 female Utah school children, mean age 7.5 years, assisted by their parents, and recorded by household measure. Data, first recorded as meals eaten, were used to develop three models for the estimation of available iron from total daily iron intake. It was concluded that available iron can be estimated from total iron intake by two of these models, as compared with the currently used model, which estimates available iron from data recorded by meal.
Additionally, meal patterns of those factors involved with the estimation of available iron were investigated. The intake of dietary ascorbic acid and total iron was found to be evenly distributed among meals; approximately 10% of these nutrients was consumed as snacks. Of the meat, fish, poultry and the iron in those products consumed; 36% was taken at lunch, and 54% at dinner. Only 5% of the meat, fish, and poultry iron was consumed as snacks. The available iron distribution for breakfast, lunch, dinner, and snacks was 21.0%, 30.8%, 42.5% and 5.7%, respectively.
Previous studies have investigated the characteristics of diets which provide 9 mg of iron per 1000 kcal of energy consumed. These diets have been shown to include larger portions of vegetables, fruits, and cereal products. In this study, these high-iron dense characteristics were studied as they pertain to total available iron intake. It was concluded that the high-iron dense diet receives more total available iron from the nonheme iron than from the heme iron consumed. Thus, it is conceivable that those dietary characteristics shown to provide a high-iron dense diet may also provide a high available iron intake.
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Lian, Yiqian. « Chromium and iron organometallics in organic synthesis synthetic studies toward total synthesis of taxol and chromium to iron transfer processes / ». Diss., Connect to online resource - MSU authorized users, 2006.
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Sun, Huikai. « Iron tricarbonyl promoted cyclizations potential application toward total synthesis of 18-deoxycytochalasin H / ». online version, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=case1190143838.
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SUN, HUIKAI. « IRON TRICARBONYL PROMOTED CYCLIZATIONS : POTENTIAL APPLICATION TOWARD TOTAL SYNTHESIS OF 18-DEOXYCYTOCHALASIN H ». Case Western Reserve University School of Graduate Studies / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=case1190143838.
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Silva, Ana Lúcia Pereira Nascimento da. « Morfoanatomia e teores de nutrientes em gemas de pereira ». Universidade Federal de Pelotas, 2012. http://repositorio.ufpel.edu.br/handle/ri/1990.
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Previous issue date: 2012-09-28The pear crop in southern Brazil emerges as a consistent alternative to the diversification of temperate fruit. However, temperature variations influence the physiological processes involved in internal input and output dormancy that may be connected to the anatomy, physiology and metabolism of the plant. Therefore, this study aimed to evaluate the characteristics and the possible involvement morphoanatomic levels of protein, carbohydrate, calcium and iron flower bud abortion in pear cultivar Nijisseik, in southern Brazil. It were determined the numbers of primordia, doubles inflorescences, length, diameter, volume, total carbohydrate content, total protein content, calcium and iron in gems. The number of primordia was higher in the second and the fourth harvest showing sharp reduction from fourth to fifth collection. The first to the second collection was significantly decreased length of gems, with a slight increase which was maintained in the other harvests. The diameter and volume decreased during the collections. The total carbohydrate had variations during the months of collection, a reduction during the month of august with a significant drop until september. A significant increase in protein concentration was determined from august to september, at this time there was an increase in temperature and reduction in hours of cold. The calcium content was reduced during the months from june to august and subsequent increase until september. Iron had a small reduction from june to july and after had increased as the months passed. According to the results, it can be concluded that the greater the number of origins, the greater the number of double inflorescence and the greater the intensity of necrosis. This fact can be considered as one of the first factors to trigger abortion, followed by lack of nutrients. Abortion may be involved with the reduction of total carbohydrate, and a shortage of calcium and also with increased iron in the period of dormancy of the buds. Perhaps the total proteins not have an effective involvement in bud abortion. The bud abortion is not caused by just one factor, but several factors may be interrelated, necessitating the continuation of studies covering the possible causes of this problem.
O cultivo da pereira surge no Sul do Brasil como uma alternativa consistente para a diversificação da fruticultura de clima temperado. No entanto, as variações de temperatura influenciam nos processos fisiológicos internos envolvidos na entrada e saída da endodormência que podem estar ligados à anatomia, fisiologia e metabolismo da planta. Portanto, esta pesquisa teve por objetivo avaliar as características morfoanatômicas e o possível envolvimento dos níveis de proteína, carboidrato, cálcio e ferro no abortamento de gemas florais de pereira, cultivar Nijisseik, no Sul do Brasil. Foram determinados os números de primórdios, de duplas inflorescências, comprimento, diâmetro, volume, teor de carboidrato total, proteína total, cálcio e ferro das gemas. O número de primórdios foi maior da segunda a quarta coleta e apresentou brusca redução da quarta para a quinta coleta. Da primeira para a segunda coleta houve significativa diminuição do comprimento de gemas, ocorrendo leve aumento que se manteve nas demais coletas. O diâmetro e o volume diminuíram no decorrer das coletas. O teor de carboidratos totais teve variações durante os meses de coleta, apresentando redução durante o mês de agosto com expressivo decréscimo até setembro Um incremento significativo de proteína foi observado de agosto a setembro, época em que ocorreu elevação de temperatura e redução nas horas de frio. O teor de cálcio foi reduzido no decorrer dos meses de junho a agosto, posteriormente aumentando até setembro. O ferro apresentou pequena redução do mês de junho para julho, aumentando após conforme o passar dos meses. Os resultados obtidos induzem a concluir que quanto maior o número de primórdios, maior o número de dupla inflorescência e maior a intensidade de necrose. Este fato pode ser considerado como um dos primeiros fatores a desencadear o abortamento, seguido pela falta de nutrientes. O abortamento pode estar envolvido com a redução do teor de carboidratos totais, aliado a escassez de cálcio e ao aumento do ferro no período de dormência das gemas. As proteínas totais provavelmente não tenham um efetivo envolvimento no abortamento de gemas. O abortamento de gemas não é causado apenas por um fator, mas sim por vários fatores que podem estar interligados, sendo necessária a continuação de estudos abrangendo as possíveis causas deste problema.
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Cooper, Susan. « Understanding Size-Dependent Structure and Properties of Spinel Iron Oxide Nanocrystals Under 10 nm Diameter ». Thesis, University of Oregon, 2019. http://hdl.handle.net/1794/24523.
Texte intégralRésumé :
Iron oxide nanoparticles (NPs) are promising materials for use in many applications, including new cancer treatments and in cleaning water, because they exhibit size-dependent magnetic and absorptive properties. NP properties are caused by structural attributes of the NPs, like surface disorder and cation vacancies. However, NP synthetic methods also impact structure, therefore properties, of NPs. Furthermore, the synthetic method is often changed in order to change the core diameter of NPs. Determining if properties are caused by the dimensions of the NP is impossible if there are also structural features present in the NP caused by the synthetic method, like grain boundaries or polycrystalline shells. In Chapter II of this dissertation, we show a new continuous growth synthesis of spinel iron oxide where the diameter of NPs is changed by the amount of precursor added to the reaction, meaning the only structural feature changing between the NPs is size. Continuous growth, therefore, can be used to probe the impact that size has on NP structure and properties. We report that saturation magnetization of NPs produced from continuous growth is size-dependent and higher in magnitude than NPs of the same core diameter made by other syntheses. In chapter III of this dissertation we determine nanoscale structure by Pair Distribution Function (PDF) analysis of Total X-ray Scattering data of NPs isolated from the reaction with core diameters between 3-10 nm. In Chapter IV of this dissertation we monitored the growth of NPs in situ with Total X-ray Scattering to gain insight on the structures of NPs while forming. In situ measurements of Total X-ray Scattering data gave insights into how precursor oxidation state influences the structures formed during formation of NPs, with more oxidized precursor giving a more oxidized product and a reduced precursor yielding a more reduced product even though the NPs formed by either method are indistinguishable by ex situ analysis.
This dissertation includes previously published and unpublished co-authored material.2021-04-30
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Onyegbule, Peter Nnamdi. « Impact of Peat Bogs on the Brownification of River Storån and Lake Bolmen ». Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-42679.
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Freshwater bodies have been long observed to become browner within the northern hemisphere. This brownification, has made drinking water production difficult, since increased organic content in freshwaters requires higher dosages of chemicals during water treatment. Changes in land use through increased industrial forestry, decreased sulphur deposition from reduced industrial emissions, changing patterns of hydrological and meteorological parameters resulting from climate change, including recently highlighted increase in iron concentrations have been proposed to explain brownification. Drained peat bogs are man-made source of brownifying substances, capable of causing brownification in the rivers and lakes where the water ends up. This research is aimed at investigating dissolved organic matter, total organic carbon, iron, phosphorous, nitrogen and colour in bog ditches draining into the Storån River and Lake Bolmen in southern Sweden, in order to answer these research questions: (1) What are the differences in the level of water quality parameters, pH, conductivity, temperature, DOM, TOC, total phosphorous, total nitrogen, Fe and colour, between bog ditches and Storån River? And what could be the outcome of Colour absorbance comparison, between bog ditches, Storån and lake Bolmen as a single control sample? (2) Is there any association among the different water quality parameters, pH, conductivity, temperature, DOM, TOC, total phosphorous, total nitrogen, Fe and colour within the bog ditch water? Water samples from bog ditches and their corresponding Storån River locations, were used in the analysis. DOM and flow showed significant differences, after statistical test for difference. Conductivity, DOM, total nitrogen and total phosphorous exhibited significant correlations with pH. TOC also had a correlation with DOM., while colour correlated and depended strongly on Fe, within the bog ditches. Therefore, the bog ditch has behaved to contribute some amount of the brownification, found in Southern Swedish Lakes and Rivers. This knowledge might be useful in future, for more studies and control of Swedish fresh water brownification.
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Dhakal, Sushil. « Study of DD Neutrons and their Transmission in Iron Spheres ». Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1478097309006943.
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Breet, Petronella. « A comparison between the effects of black tea and rooibos on the iron status of primary school children / P. Breet ». Thesis, North-West University, 2003. http://hdl.handle.net/10394/172.
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Gontier, Adrien. « Quantification de l'altération dans les sols par les déséquilibres radioactifs : approche sur sol total et phases minérales séparées ». Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAH011/document.
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Ce travail porte sur l'utilisation des déséquilibres radioactifs dans les échantillons de sols totaux, et des fractions minérales séparées. Les objectifs étaient d'évaluer : 1) l'impact d'un changement de végétation et de la granulométrie de la roche mère dans les sols sur les déséquilibres, 2) les phases minérales secondaires capables d'enregistrer des informations temporelles, et leur séparation chimique et 3) l’information temporelle portée par les minéraux primaires. Ce travail a mis en évidence sur le site de Breuil-Chenue que les couches les plus profondes du sol (< 40cm) ne montrent pas d’impact de la végétation ou de la granulométrie de la roche mère sur les déséquilibres radioactifs. Les faibles vitesses de production du sol (~1-2 mm/ka) obtenues reflètent la très faible érosion physique affectant ce site situé sur un plateau. La seconde partie de ce travail a permis d'identifier un protocole permettant d’extraire les oxydes de fer sans création de fractionnement chimique. Enfin, l'analyse de biotites d’un profil du même site a montré que les déséquilibres U/Th permettaient de déterminer de façon indépendante les vitesses d’altération in situ des minéraux dans les solsThe aim of the present study was to evaluate weathering and soil formation rates using U-Th disequilibria in bulk soil or separated minerals. The specific objectives of this work were to evaluate the use of U-Th chronometric tools 1) regarding the impact of a land cover change and the bedrock characteristics 2) in selected secondary mineral phases and 3) in primary minerals. On the Breuil-Chenue (Morvan) site, no vegetation effect neither a grain size effect was observed on the U-Th series in the deepest soil layers (< 40cm). The low soil production rate (1-2 mm/ka) is therefore more affected by regional geomorphology than by the underlying bedrock texture. In the second part of this work, based on a thorough evaluation of different technics, a procedure was retained to extract Fe-oxides without chemical fractionation. Finally, the analysis of biotites hand-picked from one of the studied soil profile showed that U- series disequilibria allow to independently determinate the field-weathering-rate of minerals
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Gruner, Konstanze K., Thomas Hopfmann, Kazuhiro Matsumoto, Anne Jäger, Tsutomu Katsuki et Hans-Joachim Knölker. « Efficient iron-mediated approach to pyrano[3,2-a]carbazole alkaloids - first total syntheses of O-methylmurrayamine A and 7-methoxymurrayacine, first asymmetric synthesis and assignment of the absolute configuration of (−)-trans-dihydroxygirinimbine ». Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-138748.
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Iron-mediated oxidative cyclisation provides an efficient approach to pyrano[3,2-a]carbazole alkaloids. Thus, improved routes to girinimbine and murrayacine as well as the first total syntheses of O-methylmurrayamine A and 7-methoxymurrayacine are reported. Asymmetric epoxidation of girinimbine led to (−)-trans-dihydroxygirinimbine and the assignment of its absolute configurationDieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich
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Gruner, Konstanze K., Thomas Hopfmann, Kazuhiro Matsumoto, Anne Jäger, Tsutomu Katsuki et Hans-Joachim Knölker. « Efficient iron-mediated approach to pyrano[3,2-a]carbazole alkaloids - first total syntheses of O-methylmurrayamine A and 7-methoxymurrayacine, first asymmetric synthesis and assignment of the absolute configuration of (−)-trans-dihydroxygirinimbine ». Royal Society of Chemistry, 2011. https://tud.qucosa.de/id/qucosa%3A27777.
Texte intégralRésumé :
Iron-mediated oxidative cyclisation provides an efficient approach to pyrano[3,2-a]carbazole alkaloids. Thus, improved routes to girinimbine and murrayacine as well as the first total syntheses of O-methylmurrayamine A and 7-methoxymurrayacine are reported. Asymmetric epoxidation of girinimbine led to (−)-trans-dihydroxygirinimbine and the assignment of its absolute configuration.Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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Oliveira, Jéssica Souza de. « Mineralogia e adsorção de fósforo em solos do Rio Grande do Sul ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/130549.
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No Rio Grande do Sul, são escassos os estudos relacionados à identificação e à caracterização de minerais pedogênicos em ampla escala, bem como aqueles que tratam da influência da mineralogia nos aspectos físicos e químicos dos solos. O sistema solo é resultado da combinação de fatores que atuaram ao longo do tempo geológico, fato evidente no estado do Rio Grande do Sul devido a expressiva variabilidade de classes de solos em seu território. Nesse sentido, o estudo objetivou caracterizar a composição mineralógica de solos formados nas diferentes regiões fisiográficas do Rio Grande do Sul e definir combinações físicas, químicas e mineralógicas responsáveis pela adsorção de fósforo nesses solos. Para tal, foram selecionadas 60 amostras representativas de oito classes de solos de pedoambientes oxidados e com distintos graus de intemperização. As amostras foram previamente coletadas sob vegetação natural na camada de 0 a 20 cm de profundidade. Na fração TFSA, foram realizadas análises físicas (granulometria, área superficial específica, suscetibilidade magnética), químicas (carbono orgânico total, teor de óxidos de ferro pedogênicos e óxidos de baixa cristalinidade, teor de fósforo remanescente) e mineralógicas (difratometria de raio x, estimativa dos minerais por área e largura a meia altura). Os dados foram analisados por correlações de Pearson. Os resultados mostraram ampla variação mineralógica devido aos distintos materiais de origem, influenciando a granulometria, ASE e SM. Os valores de COT mostraram relação positiva com os teores de argila e negativa, principalmente, com os teores de Prem, interferindo nos fenômenos de sorção dos solos. Os teores de Fed aumentaram conforme o incremento de argila nos solos e os teores de Feo foram baixos, ambos devido ao avançado estágio de intemperização dos solos. Na fração argila, predomina a caulinita associada a diferentes proporções de argilominerais 2:1 e óxidos de ferro. A adsorção de fósforo apresenta relação expressiva com os teores de argila, de óxidos de ferro, de carbono orgânico total e, consequentemente, com a área superficial específica do solo.There are few studies in Rio Grande do Sul making relations with the identification and characterization of pedogenic minerals on a large scale, as well as those that establish the influence of mineralogy on physical and chemical aspects of the soil. The soil system is a result of combination of factors that acted over geological time, an evident fact in Rio Grande do Sul state of due to significant variability of soil classes on his territory. Therein, the study intent to characterize the mineralogical composition of soils formed in distinct geographical regions of Rio Grande do Sul and define physical, chemical and mineralogical combinations responsible for phosphorus adsorption in these soils. However, we selected 60 representative samples of eight soil classes of oxidics pedoenvironments and with distinct degrees of mineral weathering. The samples were previously collected under natural vegetation in the 0 to 20 cm deep. In TFSA fraction, were performed physical (soil texture, specific surface area, magnetic susceptibility), chemical (total organic carbon, content of pedogenic (Fed) and low cristalinity (Feo) iron oxides, remaining phosphorus content (Prem)) and mineralogical analyzes (X ray diffraction, estimation per area and width at half height of minerals). Data were analyzed by Pearson correlations. The results showed wide mineralogical variation due to different parent materials, influencing the soil texture, SSA and MS. The TOC values were closely related with the clay fraction and negative relationship, especially with the levels of Prem, interfering in soil sorption phenomena. The Fed contents increased with the clay fraction and Feo contents were low, both due to the advanced soil stage of weathering. The clay fraction had predominantly kaolinite associated with different ratios of 2: 1 clay minerals and iron oxides. The phosphorus adsorption shows a significant relationship with the clay fraction, iron oxides, total organic carbon and, consequently, with the specific surface area of the soil.
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Petre, Catalin Florin. « Alkaline oxidation of hydrosulfide and methyl mercaptide by iron/cerium oxide-hydroxide in presence of dissolved oxygen. Possible application for removal of Total Reduced Sulfur (TRS) emissions in the Pulp & ; Paper industry ». Thesis, Université Laval, 2007. http://www.theses.ulaval.ca/2007/24330/24330.pdf.
Texte intégralRésumé :
Le sulfure d'hydrogène (H2S) et le méthyle-mercaptan (MM) sont les contaminants odorants les plus abondants parmi le quatuor qui compose les soufres réduits totaux (SRT) (H2S, CH3SH, (CH3)2S, (CH3)2S2) dans les émissions atmosphériques des industries papetières Kraft. L'association de SRT avec suffisamment d'oxygène peut être exploitée sur la base de la chimie du fer, pour convertir les SRT gazeux en produits non-volatils et non-odorants. Le procédé utilise l'oxyde-hydroxyde de Fe/Ce (Fe/CeOx) dans des solutions alcalines où l'absorption oxydative de H2S et de MM (sous forme d’ hydrosulfure et de méthyle mercapture) est favorisée. Des protocoles d'électrophorèse capillaire ont été développés pour la séparation, l'identification et la quantification de l’hydrosulfure, du méthyle mercapture, des polysulfures, du thiosulfate, du sulfate, du sulfite et du tétrathionate. La cinétique et le mécanisme de la réaction anoxique entre l’hydrosulfure et le Fe/CeOx ont été étudiés aux pH [8.0-11.0] dans un réacteur batch liquide-solide. La plupart du Fe(II) produit à pH = 9.5 reste associée à la surface de l'oxyde dans l’échelle de temps des expériences. L’hydrosulfure a été converti en thiosulfate, polysulfures et, probablement, en soufre élémentaire, alors que le Fe2+ lixivié et le thiosulfate ont montré une production équimolaire pour pH ≥ 9.5. Un mécanisme de réaction détaillé pour l'oxydation anoxique d’hydrosulfure par le Fe/CeOx a été proposé pour expliquer la formation des produits ci-dessus et dont un modèle cinétique a été dérivé pour décrire les vitesses de lixiviation du Fe(II) et de consommation d’hydrosulfure. En conditions oxiques à pH [8.5-11.0], le Fe/CeOx oxyde l’hydrosulfure via une voie combinée hétérogène-homogène pour former les mêmes produits qu’en anoxique. L'oxygène accélère l'oxydation de l’hydrosulfure par le Fe/CeOx par un facteur de plus de trois en comparaison avec la réaction anoxique. L'oxygène assume un double rôle : d'abord, il ré-oxyde le fer de Fe(II) à Fe(III); en second lieu, il favorise l'oxydation de l`hydrosulfure vers les polysulfures et de ces-ci vers le thiosulfate, un produit non-volatile et non-odorant. L'oxydation du méthyle mercapture par Fe/CeOx a été étudiée aux différentes valeurs du pH [10.5-12] en conditions anoxique et oxique. Des conversions de mercapture allant jusqu'à 100% ont été obtenues en conditions oxiques bien que la conversion du mercapture se soit avérée tributaire de la quantité d'oxygène dissous. L'interférence avec l’hydrosulfure co-mélangé avec le mercapture a causé une inhibition dans la conversion des deux polluants. Une telle inhibition est due aux polysulfures naissants formés par l'oxydation de l’hydrosulfure. L'oxydation du méthyle mercapture par le système Fe/CeOx/O2 n'a pas affecté la capacité de régénération du Fe(III) de surface par l'oxygène dissous. Fe/CeOx semble être un matériau très prometteur pour un éventuel procédé de lavage-oxydatif pour l’élimination du méthyle mercaptan dans les émissions des industries papetières de type Kraft.Hydrogen sulfide (H2S) and methyl mercaptan (MM) are the most abundant odor contaminants among the Total Reduced Sulfur (TRS) quartet (H2S, CH3SH, (CH3)2S, (CH3)2S2) contained in the Kraft mill atmospheric emissions. The association of TRS with sufficient oxygen could be taken advantage of, based on the iron chemistry, to convert TRS gases to odorless non-volatile products. The process uses Fe/Ce oxide-hydroxide (Fe/CeOx) slurried in alkaline solutions where both H2S and MM oxidative absorption (in the form of hydrosulfide and methyl mercaptide) is promoted. Capillary electrophoresis protocols were developed for the separation, identification and quantification of hydrosulfide, methyl mercaptide, polysulfides, thiosulfate, sulfate, sulfite and tetrathionate. The kinetics and mechanism of the anoxic reaction between hydrosulfide and Fe/CeOx were studied for pH [8.0-11.0] in a batch slurry reactor. Most of Fe(II) produced at pH = 9.5 remained associated with the oxide surface in the time-frame of the experiments. Hydrosulfide was converted into polysulfides, thiosulfate and, probably, elemental sulfur, while the leached Fe2+ and thiosulfate dovetailed equimolarly. A detailed reaction pathway of the anoxic oxidation of hydrosulfide by Fe/CeOx was proposed for explaining the formation of above products and whereof a kinetic model was derived to depict the Fe2+ leaching and hydrosulfide consumption rates. In oxic conditions at pH [8.5-11.0], Fe/CeOx will oxidize hydrosulfide via a combined heterogeneous-homogenous pathway to yield the same products as in anoxia. Oxygen enhanced Fe/CeOx-promoted hydrosulfide oxidation by more than a factor three when compared with anoxic reaction. Oxygen is believed to have a double role: first, it re-oxidizes iron from Fe(II) to Fe(III); second, it promotes oxidation of hydrosulfide to polysulfides which in turn transforms into non-volatile, non-odorous thiosulfate. The reaction between methyl mercaptide and Fe/CeOx was studied at different pH values [10.5-12] both in anoxic and oxic conditions. Up to 100% conversions of mercaptide were obtained in oxic conditions, though the mercaptide conversion was found to be tributary to the dissolved oxygen. Interference with hydrosulfide co-mixed with mercaptide caused an inhibition in the conversion for both pollutants, due to the incipient polysulfides formation. The oxidation of methyl mercaptide by the Fe/CeOx/O2 system did not affect the re-oxidative regeneration of surface Fe(III) by O2. Fe/CeOx appears to be a very promising material for a redox-scrubbing process targeting the TRS emissions from Kraft mills, via in situ regeneration of Fe(III) sites by O2.
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Petre, Cătălin Florin. « Alkaline oxidation of hydrosulfide and methyl mercaptide by iron/cerium oxide-hydroxide in presence of dissolved oxygen : possible application for removal of Total Reduced Sulfur (TRS) emissions in the Pulp & ; Paper industry ». Doctoral thesis, Université Laval, 2007. http://hdl.handle.net/20.500.11794/19640.
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Tableau d'honneur de la Faculté des études supérieures et postdoctorales, 2006-2007Le sulfure d'hydrogène (H2S) et le méthyle-mercaptan (MM) sont les contaminants odorants les plus abondants parmi le quatuor qui compose les soufres réduits totaux (SRT) (H2S, CH3SH, (CH3)2S, (CH3)2S2) dans les émissions atmosphériques des industries papetières Kraft. L'association de SRT avec suffisamment d'oxygène peut être exploitée sur la base de la chimie du fer, pour convertir les SRT gazeux en produits non-volatils et non-odorants. Le procédé utilise l'oxyde-hydroxyde de Fe/Ce (Fe/CeOx) dans des solutions alcalines où l'absorption oxydative de H2S et de MM (sous forme d’ hydrosulfure et de méthyle mercapture) est favorisée. Des protocoles d'électrophorèse capillaire ont été développés pour la séparation, l'identification et la quantification de l’hydrosulfure, du méthyle mercapture, des polysulfures, du thiosulfate, du sulfate, du sulfite et du tétrathionate. La cinétique et le mécanisme de la réaction anoxique entre l’hydrosulfure et le Fe/CeOx ont été étudiés aux pH [8.0-11.0] dans un réacteur batch liquide-solide. La plupart du Fe(II) produit à pH = 9.5 reste associée à la surface de l'oxyde dans l’échelle de temps des expériences. L’hydrosulfure a été converti en thiosulfate, polysulfures et, probablement, en soufre élémentaire, alors que le Fe2+ lixivié et le thiosulfate ont montré une production équimolaire pour pH ≥ 9.5. Un mécanisme de réaction détaillé pour l'oxydation anoxique d’hydrosulfure par le Fe/CeOx a été proposé pour expliquer la formation des produits ci-dessus et dont un modèle cinétique a été dérivé pour décrire les vitesses de lixiviation du Fe(II) et de consommation d’hydrosulfure. En conditions oxiques à pH [8.5-11.0], le Fe/CeOx oxyde l’hydrosulfure via une voie combinée hétérogène-homogène pour former les mêmes produits qu’en anoxique. L'oxygène accélère l'oxydation de l’hydrosulfure par le Fe/CeOx par un facteur de plus de trois en comparaison avec la réaction anoxique. L'oxygène assume un double rôle : d'abord, il ré-oxyde le fer de Fe(II) à Fe(III); en second lieu, il favorise l'oxydation de l`hydrosulfure vers les polysulfures et de ces-ci vers le thiosulfate, un produit non-volatile et non-odorant. L'oxydation du méthyle mercapture par Fe/CeOx a été étudiée aux différentes valeurs du pH [10.5-12] en conditions anoxique et oxique. Des conversions de mercapture allant jusqu'à 100% ont été obtenues en conditions oxiques bien que la conversion du mercapture se soit avérée tributaire de la quantité d'oxygène dissous. L'interférence avec l’hydrosulfure co-mélangé avec le mercapture a causé une inhibition dans la conversion des deux polluants. Une telle inhibition est due aux polysulfures naissants formés par l'oxydation de l’hydrosulfure. L'oxydation du méthyle mercapture par le système Fe/CeOx/O2 n'a pas affecté la capacité de régénération du Fe(III) de surface par l'oxygène dissous. Fe/CeOx semble être un matériau très prometteur pour un éventuel procédé de lavage-oxydatif pour l’élimination du méthyle mercaptan dans les émissions des industries papetières de type Kraft.
Hydrogen sulfide (H2S) and methyl mercaptan (MM) are the most abundant odor contaminants among the Total Reduced Sulfur (TRS) quartet (H2S, CH3SH, (CH3)2S, (CH3)2S2) contained in the Kraft mill atmospheric emissions. The association of TRS with sufficient oxygen could be taken advantage of, based on the iron chemistry, to convert TRS gases to odorless non-volatile products. The process uses Fe/Ce oxide-hydroxide (Fe/CeOx) slurried in alkaline solutions where both H2S and MM oxidative absorption (in the form of hydrosulfide and methyl mercaptide) is promoted. Capillary electrophoresis protocols were developed for the separation, identification and quantification of hydrosulfide, methyl mercaptide, polysulfides, thiosulfate, sulfate, sulfite and tetrathionate. The kinetics and mechanism of the anoxic reaction between hydrosulfide and Fe/CeOx were studied for pH [8.0-11.0] in a batch slurry reactor. Most of Fe(II) produced at pH = 9.5 remained associated with the oxide surface in the time-frame of the experiments. Hydrosulfide was converted into polysulfides, thiosulfate and, probably, elemental sulfur, while the leached Fe2+ and thiosulfate dovetailed equimolarly. A detailed reaction pathway of the anoxic oxidation of hydrosulfide by Fe/CeOx was proposed for explaining the formation of above products and whereof a kinetic model was derived to depict the Fe2+ leaching and hydrosulfide consumption rates. In oxic conditions at pH [8.5-11.0], Fe/CeOx will oxidize hydrosulfide via a combined heterogeneous-homogenous pathway to yield the same products as in anoxia. Oxygen enhanced Fe/CeOx-promoted hydrosulfide oxidation by more than a factor three when compared with anoxic reaction. Oxygen is believed to have a double role: first, it re-oxidizes iron from Fe(II) to Fe(III); second, it promotes oxidation of hydrosulfide to polysulfides which in turn transforms into non-volatile, non-odorous thiosulfate. The reaction between methyl mercaptide and Fe/CeOx was studied at different pH values [10.5-12] both in anoxic and oxic conditions. Up to 100% conversions of mercaptide were obtained in oxic conditions, though the mercaptide conversion was found to be tributary to the dissolved oxygen. Interference with hydrosulfide co-mixed with mercaptide caused an inhibition in the conversion for both pollutants, due to the incipient polysulfides formation. The oxidation of methyl mercaptide by the Fe/CeOx/O2 system did not affect the re-oxidative regeneration of surface Fe(III) by O2. Fe/CeOx appears to be a very promising material for a redox-scrubbing process targeting the TRS emissions from Kraft mills, via in situ regeneration of Fe(III) sites by O2.
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MATOS, IZABELA T. de. « Padronização dos radionuclídeos F-18 e In-111 e determinação dos coeficientes de conversão interna total para o In-111 em sistema de coincidência por software ». reponame:Repositório Institucional do IPEN, 2014. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10615.
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Dissertação (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Reidhead, Joshua Glen. « Significance of the Rates of Atmospheric Deposition Around Utah Lake and Phosphorus-Fractionation of Local Soils ». BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/7685.
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Eutrophic Utah Lake receives a large nutrient load from a variety of sources, includingtreated wastewater discharges, runoff and tributaries, recycling from bottom sediments andAtmospheric Deposition (AD). AD was the focus of this study and was comprised of twocomplementary parts. First was a study of nitrogen and phosphorus depositions from theatmosphere, and second was a study of phosphorous as contained in soils near Utah Lake viafractionation methods.The soil samples were found to contain approximately 1,000 mg-P/kg soil for totalphosphorus (TP). A separate phosphorus (P) fractionation gave slightly higher values, excludingthe residual P, we are 95% confident that one gram of sample soil contains between 2.2 and 4.3percent water soluble P, 0.6 to 1.1 percent loosely-bound P, 2.5 to 4.4 percent aluminum andiron-bound P, and 90.7 to 94.2 percent calcium-bound P.AD results indicate that during the period from April 1 to Nov 17, 2018, Utah Lakereceived approximately 58 tons of soluble reactive P, 153 tons of TP, 118 tons of nitrogen (N)from nitrate, and 387 tons of N from ammonium via AD.Nutrient quantities from AD are very large compared to the 17 ton/yr of P needed for aeutrophic loading to the lake. Because of the very large overall nutrient loading to Utah Lake, itis likely that some other limiting growth factors are controlling algal growth.
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Gbolo, Prosper. « Chemical and Geological Controls on the Composition of Waters and Sediments in Streams Located within the Western Allegheny Plateau : The Shade River Watershed ». Ohio : Ohio University, 2008. http://www.ohiolink.edu/etd/view.cgi?ohiou1213283066.
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Soares, Vitória Regina Bispo. « Desenvolvimento de processo para incorporação da etapa de otimização de parâmetros analíticos em procedimentos automatizados de análises por injeção sequencial ». Instituto de Química, 2009. http://repositorio.ufba.br/ri/handle/ri/20241.
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CNPq
Para aumentar o nível de automatização no desenvolvimento de procedimentos analíticos em sistemas de análises por injeção sequencial foi proposta uma rotina em linguagem QuickBasic que permitia incorporar a etapa de otimização multivariada como uma das etapas do processo analítico, simplificando o gerenciamento do sistema. A rotina foi desenvolvida para sistemas de análises por injeção sequencial, uma vez que esta estratégia de análises em fluxo pode executar diferentes procedimentos sem reconfiguração do sistema. O processo automatizado de otimização, calibração e medida foi aplicado para as determinações espectrofotométricas de ferro total e de captopril em medicamentos, empregando os métodos da 1,10-o-fenantrolina e do acoplamento com o radical iminoquinona, respectivamente. Para rotina de otimização desenvolvida foi selecionado o sinal líquido como resposta e a intervenção do operador se restringiu a selecionar as variáveis do sistema sob otimização, definir os domínios experimentais de cada variável e escolher o desenho experimental a ser executado. Entretanto, caso as condições ótimas não fossem encontradas no domínio experimental selecionado a rotina foi programada de modo a sugerir ao operador os deslocamentos que deveriam ser feitos nos domínios experimentais. Os fatores investigados para a determinação de ferro total em amostras de fortificantes foram os volumes amostrados dos reagentes e a vazão da solução transportadora, enquanto que para o captopril foram investigados os volumes amostrados dos reagentes, a acidez da solução do oxidante e da solução da amina aromática, além da vazão da solução transportadora. Nas condições otimizadas os graus de sopreposição de zonas para ambos os procedimentos variaram entre 0,79 e 1, indicando a eficiente mistura das soluções das amostras e reagentes no percurso analítico. O procedimento SIA otimizado para a determinação do teor de ferro total em fortificantes apresentou baixa dispersão (<2%), limite de quantificação de 1,43 mg L-1 , com consumo de 0,7 mg de 1,10-o- fenantrolina e 6 mg de ácido ascórbico por determinação. A freqüência analítica foi de 60 determinações h-1 e os resultados obtidos para diferentes amostras de fortificantes foram comparados com o mesmo método em batelada e não apresentaram diferenças significativas para 95% de confiabilidade. Trinta determinações de captopril em produtos farmacêuticos por hora de trabalho foram executadas pelo procedimento de análise por injeção seqüencial otimizado consumindo 0,15 mg de sulfato de N-N-dimetil-p-fenilodiamina (DMPD) e 4 mg de FeCl3.6H2O por determinação. Faixa linear de trabalho entre 2,65 e 100 mg L-1 e boa precisão (ca. 1%) foram também obtidas. Os teores de captopril em amostras de produtos farmacêuticos foram determinados pelo procedimento proposto e os resultados, quando comparados com o método iodométrico de referência, não apresentaram diferenças significativa para 95% de confiança
A QuickBasic routine was proposed to increase the automatization in the development of analytical process for sequential injection analysis system in order to permit the inclusion of multivariated optimization as one of the steps of analytical process leading to simplify the system management. The routine was developed for sequential injection analysis once this flow analysis strategy can perform diverse analytical procedures in the same manifold. The automatized process for optimization, calibration and measurement was applied to determine the total iron concentration in pharmaceutical formulations by 1,10-o-phenantroline spectrophotometric method, as well as captopril in pharmaceutical formulations based on coupling reaction with iminoquinone radical. Sensitivity (net signal) was selected as dependent parameter for the optimization step and the analyst action was limited to select the parameters to be optimized and the experimental design to be used as well to define the experimental domains of all parameters. A decision of the analyst was also expected in the cases where the optimal conditions were not attained in the domains previously selected and, once new domains are suggested by the software, a new sequence of experiments will be carried out with human agreement. Aliquots volumes of reagents and carrier solution flow rate were the parameters evaluated for total iron determination in supplements, while the acidity and volumes of reagents solutions and the flow rate of carrier solution were optimized for captopril determination flow procedure. For both analytical procedures in the optimized conditions the index of zone overlapping was varied from 0.79 and 1, suggesting an efficient mixture of solutions in the analytical path. The optimized SIA procedure for total iron determination in supplement samples has low dispersion (<2%), limit of quantification of 1.43 mg L-1, leading to consume 0.7 mg of 1,10-o-phenantroline and 6 mg of ascorbic acid per determination. An analytical throughput of 60 determinations h-1 was estimated and no significant difference (95% confidence level) was observed by comparing the results obtained by the flow method in optimized conditions and those obtained by the spectrophotometric procedure in batch mode. Thirty captopril determinations in pharmaceutical formulations per hour were carried out by employing the optimized sequential injection analysis procedure, consuming 0.15 mg of N,N-dimethyl-p-phenylenediamine (DMPD) and 4 mg of FeCl3.6H2O. Linear range from 2.65 to 100 mg L-1 with high precision (ca. 1%) was also obtained and no significant differences (95% confidence level) were observed by comparing the optimized flow procedure with the iodometric reference method.
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Barros, Catarina João Gil de. « Piroplasmose equina : diagnóstico molecular e avaliação de alterações hematológicas e de biomarcadores inflamatórios em cavalos com doença clínica e subclínica ». Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2018. http://hdl.handle.net/10400.5/16331.
Texte intégralRésumé :
Dissertação de Mestrado Integrado em Medicina VeterináriaAtualmente, o PCR quantitativo (qPCR) constitui o teste de eleição para diagnóstico de infeções por Theileria equi e Babesia caballi. O papel dos marcadores da inflamação na piroplasmose equina (PE) permanece pouco estudado, não só no diagnóstico e monitorização mas também enquanto potenciais indicadores preditivos da doença. Tendo em conta a natureza intracelular obrigatória dos agentes da PE, colocou-se a seguinte hipótese: a resposta inflamatória na PE difere da de outras doenças associadas a inflamação. Além disso, procurou responder-se às seguintes questões: 1) Qual a utilidade do hemograma e marcadores de inflamação aguda no diagnóstico precoce da PE? 2) Quais as vantagens da utilização do qPCR no diagnóstico da PE? Os principais objetivos deste estudo foram: 1) Caracterizar e quantificar alterações do hemograma, proteínas totais, amilóide sérica A (SAA), fibrinogénio e ferro plasmáticos na PE; 2) Comparar os resultados obtidos entre cavalos com doença clínica (grupo PC) e subclínica (grupo SC); 3) Avaliar o valor diagnóstico destes testes para a PE clínica e outras causas de febre de origem inespecífica (grupo NS); 4) Determinar a carga parasitária em amostras positivas e comparar a sensibilidade da microscopia ótica, considerando os resultados obtidos por diagnóstico molecular. Cada amostra foi submetida a qPCR para deteção de T. equi e B. caballi, análise hematológica, doseamento de proteínas totais, SAA, fibrinogénio e ferro plasmáticos. Foram identificadas diferenças significativas (p < 0,05) no valor absoluto de monócitos entre os grupos PC-NS e PC-SC, na SAA entre os grupos PC-SC e no ferro plasmático entre os grupos PC-NS e PC-SC. 75% dos cavalos do grupo SC apresentaram neutrofilia sem desvio à esquerda. Apenas foram observadas formas de T. equi em esfregaços sanguíneos de cavalos com parasitémia igual ou superior a 7,2x10 2 parasitas/μL. Este estudo evidenciou não só as vantagens do qPCR no diagnóstico da PE, mas também que esta doença se caracteriza por uma resposta inflamatória associada a alterações do hemograma e de marcadores inflamatórios, em que o valor absoluto de monócitos, SAA e ferro plasmático constituíram os biomarcadores mais sensíveis para a deteção da doença.
ABSTRACT - EQUINE PIROPLASMOSIS: MOLECULAR DIAGNOSIS AND EVALUATION OF HEMATOLOGICAL AND INFLAMMATORY BIOMARKERS CHANGES IN HORSES WITH CLINICAL AND SUBCLINICAL DISEASE - Currently, real-time PCR (qPCR) is considered the best technique to diagnose Theileria equi and Babesia caballi infections. Furthermore, the role of inflammatory biomarkers in equine piroplasmosis (EP) is still not clear, not only for diagnostic and monitoring purposes but also for its use as disease predictive indicators. Considering the obligate intracellular nature of EP agents, the following hypothesis was set: the inflammatory response in EP differs from other inflammatory diseases. Moreover, the following questions were asked: 1) What is the usefulness of hemogram and acute inflammation markers in the early detection of EP?; 2) What are the advantages of using qPCR to diagnose EP? The main goals of this study were: 1) To define and quantify changes in hemogram, total proteins, serum amyloid A (SAA), plasma fibrinogen and plasma iron in horses with EP; 2) To compare the obtained results between horses with clinical (PC group) and subclinical disease (SC group); 3) To evaluate the diagnostic value of hemogram and inflammation markers for EP and other causes of unknown origin fever (NS group); 4) To calculate the parasitemia in EP positive horses and compare the sensitivity of optic microscopy, considering the molecular diagnosis results. Each sample was subjected to a qPCR for T. equi and B. caballi detection, hematological analysis and determination of total proteins, SAA, plasma fibrinogen and plasma iron. There were significant differences (p < 0,05) in monocytes absolute value between PC-NS and PC-SC groups, in SAA between PC-SC groups and in plasma iron between PC-NS and PC-SC groups. A total of 75% SC group horses showed neutrophilia without left shift. T. equi was only found in blood smears that had a parasitemia equal or higher than 7,2x10 2 parasites/μL. This study highlights the usefulness of qPCR in EP diagnosis and that this disease is characterized by an inflammatory response associated with hemograma and inflammatory markers changes, in which monocytes absolute value, SAA and plasmatic iron demonstrate higher sensitivity in the detection of EP.
info:eu-repo/semantics/publishedVersion
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Janáček, Martin. « Energetické parametry jednofázových asynchronních motorů ». Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-242197.
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The master's thesis deals and introduces a single-phase inductions machines, the principle of operation, types of design and operating conditions. This thesis includes analysis of individual losses in the machine and reduce the possibility of different ways. After a theoretical proposal for reducing losses are measured by mass-produced single-phase induction machine. Further machine modifications proposed for reducing losses in the stator windings and designed a prototype machine with the adjustment of the magnetic circuit to reduce iron losses made by ATAS elektromotory Nachod a.s. The results are supplemented by a simulation using software Maxwell RMxprt and finite element method (FEM). Finally, they are compared to each machines modifications mainly in terms of energy consumption.
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Mille, Stéphane. « Synthèse totale de la (+ ou -)-cis-y-irone : essais d'application à la préparation de la (+)-cis-y-irone ». Le Mans, 1999. http://www.theses.fr/1999LEMA1005.
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L'odeur de violette est tres recherchee dans l'industrie de la parfumerie. La ()-cis--irone a ete isolee de rhizomes d'iris et identifiee comme le principal vecteur de la fine et puissante odeur de violette. C'est pourquoi nous avons envisage une nouvelle voie de synthese de la ()-cis--irone en serie racemique. Les principales etapes de cette synthese sont donc : (i) la fabrication a grande echelle du 3,4-dimethylpenta-1,3-diene ; (ii) sa reaction de diels-alder avec l'anhydride maleique ; (iii) les hydrogenolyses du carbonyle le moins encombre et de la double liaison carbone-carbone ; (iv) la transformation en cis--irone apres l'ouverture de la lactone par le phenylselenolate de sodium. Nous en avons aussi profite pour etudier la conformation de l'adduit obtenu lors de la reaction de diels-alder et celle d'un sous produit longtemps present en rmn et en modelisation moleculaire a differents niveaux de theorie. Le groupe phenylselanyle introduit par action du phenylselenolate de sodium sur la lactone de mori est precurseur de la double liaison exocyclique. Afin de completer le squelette de la cis--irone une chaine a 3 carbones, possedant une fonction carbonyle sur le second carbone, doit etre introduite par reaction de wittig sur un aldehyde, la generation de la double liaison e etant obtenu simultanement. L'ordre de ces deux etapes (generation de la double liaison exocyclique et introduction de la chaine a trois carbones) peut etre inverse. Une etude publiee dans la litterature a montre que seul l'enantiomere (+) est responsable de l'odeur de violette, l'antipode () etant sans odeur. C'est pourquoi nous avons envisage une synthese enantiomeriquement enrichie d'un precurseur de la (+)-cis--irone, la chiralite etant introduite par un groupement sulfoxyde. Nous avons donc synthetise plusieurs sulfinyldienes afin d'etudier leur reactivite dans la reaction de diels-alder avec l'anhydride maleique. Pour obtenir la lactone desiree, trois hydrogenolyses doivent etre effectuees (celles du carbonyle le moins encombre et de la double liaison carbone-carbone ayant ete mise au point en serie racemique, seule la coupure de la liaison carbone-soufre n'ayant pas ete testee). Ce travail de these offre donc de nouvelles syntheses de la ()-cis--irone et d'un precurseur enantiomeriquement enrichi.
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Ozgur, Cagri. « Influence of cross-frame detailing on curved and skewed steel I-girder bridges ». Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42769.
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Curved and skewed I-girder bridges exhibit torsional displacements of the individual girders and of the overall bridge cross-section under dead loads. As a result, the girder webs can be plumb in only one configuration. If the structure is built such that the webs are plumb in the ideal no-load position, they generally cannot be plumb under the action of the structure's steel or total dead load; hence, twisting of the girders is unavoidable under dead loads. The deflected geometry resulting from these torsional displacements can impact the fit-up of the members, the erection requirements (crane positions and capacities, the number of temporary supports, tie down requirements, etc.), the bearing cost and type, and the overall strength of the structure. Furthermore, significant layover may be visually objectionable, particularly at piers and abutments.
If the torsional deflections are large enough, then the cross-frames are typically detailed to compensate for them, either partially or fully. As specified in Article C6.7.2 of the AASHTO LRFD Specifications, different types of cross-frame detailing methods are used to achieve theoretically plumb webs under the no-load, steel dead load, or total dead load conditions. Each of the cross-frame detailing methods has ramifications on the behavior and constructability of a bridge. Currently, there is much confusion and divergence of opinion in the bridge industry regarding the stage at which steel I girder webs should be ideally plumb and the consequences of out-of-plumbness at other stages. Furthermore, concerns are often raised about potential fit-up problems during steel erection as well as the control of the final deck geometry (e.g., cross-slopes and joint alignment). These influences and ramifications of cross-frame detailing need to be investigated and explained so that resulting field problems leading to needless construction delays and legal claims can be avoided.
This dissertation addresses the influence of cross-frame detailing on curved and/or skewed steel I girder bridges during steel erection and concrete deck placement by conducting comprehensive analytical studies. Procedures to determine the lack-of-fit forces due to dead load fit (DLF) detailing are developed to assess the impact of different types of cross-frame detailing. The studies include benchmarking of refined analytical models against selected full scale experimental tests and field measurements. These analytical models are then utilized to study a variety of practical combinations and permutations of bridge parameters pertaining to horizontal curvature and skew effects. This research develops and clarifies procedures and provides new knowledge with respect to the impact of cross-frame detailing methods on: 1) constructed bridge geometries, 2) cross-frame forces, 3) girder stresses, 4) system strengths, 5) potential uplift at bearings, and 6) fit-up during erection. These developments provide the basis for the development of refined guidelines for: 1) practices to alleviate fit-up difficulties during erection, 2) selection of cross-frame detailing methods as a function of I-girder bridge geometry characteristics, and 3) procedures to calculate the locked-in forces due to DLF cross-frame detailing.
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Sadeghian, Mohammad R. « A study of the significance of organisational culture for the successful implementation and operation of Total Quality Management (TQM) : a comparative study between Iran and the UK ». Thesis, University of Huddersfield, 2010. http://eprints.hud.ac.uk/id/eprint/9051/.
Texte intégralRésumé :
Iranian businesses like all others around the world need to survive and grow in the global marketplace. To facilitate this, they need true executive commitment to the provision of high quality products and services. An established way to begin this important development process is to implement Total Quality Management (TQM). By applying TQM in Iranian organisations they can begin to achieve a high standard of quality products and services at a cost that enables them to compete with their international competitors. The purpose of this research, a comparative study, was to investigate the effect of organisational culture on the successful implementation and sustainability of the operation of TQM within Iran. In the programme of research data was collected from 50 organisations in Iranian and 40 in the United Kingdom (UK). Senior executives, general managers and quality managers were interviewed. They also completed comprehensive questionnaires which identified the issues relating to the implementation and operation of TQM in their organisations. The research then focused upon problems and barriers to the introduction, implementation and sustained operation of TQM that were experienced in Iranian businesses. Specifically issues concerning the relationship between organisational culture and TQM at all levels of the organization are explored. The critical issues that this study set out to address relate to the relationships and interactions that exist within a Quality Management System, organisational culture and the changes that need to be instigated for success. In his investigations the researcher divided his study into two parts. Firstly the Hofestede national culture model (2002) was tested against the organisational culture variables established in work by Denison (2006). Secondly the Denison organisational variables were used to assess the implication of culture on the successful implementation and sustained operation of TQM. The research identified that the implementation and operation of TQM in the organisations studied in the UK was highly successful whilst in the Iranian organisations such success was identified to be low. In response to this, and based upon the knowledge and understanding gained from the investigation and analysis, the researcher presents a proposed framework to aid the successful introduction and implementation of TQM within an Iranian context.
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Abou, Serhal Cynthia. « Oxydation totale des Composés Organiques Volatils (COV) sur des catalyseurs à base de métaux de transition préparés par voie hydrotalcite : Effet des micro-ondes sur la méthode de synthèse ». Thesis, Littoral, 2018. http://www.theses.fr/2018DUNK0529/document.
Texte intégralRésumé :
Ce travail vise l'étude de l'oxydation catalytique des Composés Organiques Volatils (COVs). L'objectif principal est de trouver des matériaux catalytiques qui sont des alternatives aux métaux nobles très onéreux. La recherche des matériaux catalytiques actifs, sélectifs, stables dans le temps et à base de métaux de transition est abordée. Afin d'améliorer les performances catalytiques des métaux de transition, la dispersion de l'espèce métallique doit être optimisée en utilisant une méthode de synthèse adéquate. Les différents solides préparés ont été caractérisés par différentes techniques physico-chimiques : la Diffraction des Rayons X (DRX), les Analyses Thermiques (ATD/ATG), la Spectroscopie Infrarouge (IR), la Réduction en Température Programmée (H₂-RTP), la Microscopie Electronique à Balayage (MEB), la Spectroscopie de Photoélectrons induits par rayons X (SPX)...De plus, les oxydes obtenus ont été testés dans les réactions d'oxydation totale du COV propène. En premier lieu, nous avons focalisé notre travail sur la préparation d'une série d'oxydes mixtes Co-Mg/Al-Fe par voie hydrotalcite afin d'obtenir des propriétés intéressantes en catalyse hétérogène. Cette étude consiste surtout à évaluer la substitution des cations bivalents et trivalents. Il s'est avéré que le solide contenant à la fois du cobalt et du fer (CoFe) possède l'activité catalytique la plus élevée. L'intérêt de la voie hydrotalcite par rapport à d'autres méthodes de synthèse, telles que la méthode classique et le mélange mécanique des oxydes a été mis en évidence. En second lieu, l'utilisation des irradiations micro-ondes lors de la synthèse des matériaux hydrotalcites a été également étudiée comme une méthode de synthèse non-conventionnelle. Un effet bénéfique a été observé avec l'utilisation des micro-ondes dû principalement à des surfaces spécifiques plus élevées et à une meilleure réductibilité des espèces oxydes. En outre, cette étude vise également la mise au point de cette nouvelle méthode. De ce fait, l'optimisation de la température, durée et puissance des irradiations micro-ondes a été effectuée sur le solide CoFe, afin de montrer l'influence de chaque paramètre sur les propriétés physico-chimiques des matériaux. En troisième lieu, la synthèse d'une série de catalyseurs par voie hydrotalcite avec différentes teneurs en Co²⁺ et Fe³⁺ a été effectuée. L'influence du rapport molaire sur la structure hydrotalcite a été montrée. Une comparaison entre ces solides et ceux préparés par la méthode micro-ondes a été également abordéeThis work aims to study the catalytic oxidation of Volatile Organic Compounds (VOCs). The main objective is to find catalytic materials that are alternatives to very expensive noble metals. The search for transition metal based catalysts is investigated. Furthermore, to improve the catalytic performance of the transition metals, their dispersion must be optimized using an adequate synthetic method. The various prepared solids were characterized by different physicochemical techniques : X-ray Diffraction (XRD), Thermal Analysis (TDA/TGA), Infrared Spectroscopy (IR), Temperature Programmed Reduction by hydrogen (H₂-TPR), Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS)...Moreover, the obtained oxides were tested in the total oxidation of the VOC propene. Firstly, we focused our work on the preparation of a series of Co/Fe hydrotalcites -like samples by the traditional co-precipitation method. This study consists mainly of evaluating the substitution of bivalent and trivalent cations. It has been found that the solid containing both cobalt and iron (CoFe) has the highest catalytic activity. The interest of the hydrotalcite route compared to other methods of synthesis, such as the classical method and the mechanical mixing of oxides was put into evidence. Secondly, the use of microwave irradiation during the synthesis of hydrotalcite materials has also been studied as an unconventional method of synthesis. A beneficial effect has been observed with the use of microwaves due mainly to higher specific surface areas and better reducibility of the oxide species. In addition, an optimization of the temperature, duration, and power of the microwave irradiations was carried out on the CoFe solid, in order to show the influence of each parameter on the physico-chemical properties of the materials. Thirdly, the synthesis of a series of hydrotalcite catalysts with different ratio of Co²⁺ and Fe³⁺ was carried out. The influence of the molar ratio on the hydrotalcite structure has been shown. A comparison between these solids and those prepared by the microwave method was also discussed
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Aubineau, Thomas. « Synthèse d'hétérocycles azotés : tétrahydropyrazines et morpholines ». Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS144/document.
Texte intégralRésumé :
Les tétrahydropyrazines et les morpholines sont des hétérocycles à six chaînons comportant deux hétéroatomes en position 1,4. Les objectifs de cette thèse ont été la mise au point de nouvelles méthodes pour leur synthèse. Des tétrahydropyrazines orthogonalement protégée ont ainsi été synthétisées à partir des diamines correspondantes, grâce à l’utilisation de triméthylsilyl-benziodoxolone (TMS-EBX) comme donneur d’alcyne. Ce dérivé d’iode hypervalent s’est par ailleurs révélé être un agent alcynylant chimiosélectif des sulfonamides par rapport aux carbamates. Une approche synthétique différente a été utilisée pour le synthèse des morpholines. En s’appuyant sur les précédents résultats obtenus au laboratoire, une hétérocyclisation catalysée au Fe(III) a été mise au point. En présence d’une quantité catalytique de FeCl3.6H2O, des morpholines 2,6- et 3,5-disubstituées ont été obtenues avec de bons rendements et des diastéréosélectivités toujours en faveur des composés cis. Afin d’améliorer cette méthode pour la rendre encore plus éco-compatible, une méthode monotope a été ensuite développée, menant, à l’aide d’une catalyse séquentielle Pd(0)/Fe(III), à une diversité de morpholines à partir de vinyloxiranes et d’amino-alcools facilement synthétisables. Le changement des substrats de départ permet de faire varier la substitution des morpholines finales sans avoir à modifier les conditions réactionnelles. L’obtention majoritaire des composés de configuration relative cis a été rationalisés à partir des stabilités supposées des différents diastéréoisomères et un mécanisme hypothétique est présentéTetrahydropyrazines and morpholines are six-membered heterocycles including two heteroatoms in positions 1 and 4. The objectives of this thesis were to develop new methods for their synthesis. Orthogonnaly protected tetrahydropyrazines were thus synthesized from the corresponding diamines, thank to the use of trimethylsilyl-benziodoxolone (TMS-EBX) as an alkyne donnor. This hypervalent iodine derivative was also found to be an efficient and chemoselective alkynylating agent of sulfonamides versus carbamates. A different synthetic approach was used for the synthesis of morpholines. Relying on previous results obtained in the laboratory, an iron(III)-catalyzed heterocylization was developped. In the presence of a catalytic amount of FeCl3.6H2O, 2,6- and 3,5-disubstituted morpholines were obtained with good yields and diastereoselectivities in favor of the cis compounds. To improve this method and make it more environnementally friendly, a one-pot method was next designed, leading, with a sequential Pd(0)/Fe(III)-catalyzed process, to a diversity of morpholines from readily available vinyloxiranes and amino-alcohols. A simple switch in the starting materials gives diverse morpholines without any change in the reaction conditions. The cis-compound predominance was rationnalized from the putative stabilities of different diastereoisomeres and a hypothetical mechanism is proposed
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Twiddy, Matthew Ronald. « Prolonged dietary iron restriction alters total tissue iron but not heme iron : lack of impact on blood pressure and salt sensitivity ». Thesis, 2007. http://hdl.handle.net/1974/488.
Texte intégralRésumé :
The World Health Organization (WHO) states that iron deficiency (ID) is the preeminent global micronutrient deficiency. Maternal ID is linked to cardiovascular disease and hypertension in offspring, and yet the impact of ID on the kidney is not known. We characterized the impact of ID on circulating and tissue levels of iron and renal function.
Seven and ten week old male and female Wistar rats were fed either control (270ppm) or low iron (3ppm) diet for ten weeks. Total, non-heme and heme iron levels in liver, kidney cortex and kidney medulla were measured following the dietary period. Hematocrit decreased most in males regardless of age (Male 7-17wk: 47%→ 31%; 10-20wk: 47%→ 33.5%; Female 7-17wk: 47%→ 34%; 10-20wk: 47%→ 39%). Dietary ID markedly decreased liver and kidney cortex non-heme iron in both males and females (Female: liver-178±25 to 21±7 ppm; kidney cortex-51±9 ppm to 10±1 ppm; Male: liver-102±18 ppm to 11±1 ppm; kidney cortex 36±14 to 15±8 ppm). In contrast, non-heme iron in the kidney medulla was not significantly decreased
Secondly, in order to determine the impact of ID on renal function, blood pressure was monitored using radio-telemetry starting at six weeks of age (~175g body weight). Dietary salt challenge (5 days Low5 days HighNormal) was administered to all animals (n=16) starting at eight weeks of age. At ten weeks rats were assigned to either control (225pm) or low (3ppm) iron diet. Dietary salt challenge was repeated at 13 and 18 weeks of age respectively. Despite significant lowering of hematocrit (Control 45% Low iron 38.6%) hemodynamic changes were minimal, in that, although blood pressure was lowered following ten weeks of dietary iron restriction, blood pressure did not change in response to dietary salt (Control MAP:105.0 ± 2.5mmHg; ID MAP:100.6 ± 3.2mmHg ).
Collectively the tissue and functional analyses demonstrate that the body adapts to lowering of tissue iron supply with ID. The relative sparing of non-heme iron in the kidney medulla suggests that iron in this region of the kidney may be spared because of its importance in the systems responsible for regulating fluid and sodium balance.Thesis (Master, Pharmacology & Toxicology) -- Queen's University, 2007-07-18 12:00:09.853
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Lee, Huang-Lin, et 李凰麟. « The Reutilization Assessment and Total Iron Analysis of Stainless Steel Debris from Cold Rolling Factory ». Thesis, 2013. http://ndltd.ncl.edu.tw/handle/67577478713651238753.
Texte intégralRésumé :
碩士國立高雄應用科技大學
化學工程與材料工程系碩士在職專班
101
Stainless steel grinding debris is the waste of stainless steel cold-rolling process, because the use of rolling oil. However, the content of the oil in grinding debris is very high; therefore, it should be degreased to reduce the oil content for the re-use of grinding debris. Nevertheless, the grinding debris used directly, it will rapid to cause high temperature combustion. It is not only smoke and odor generated, but also the formation of a large flame tempered condition, will endanger the safety of factory’s operators. This study was focused on various degreasing conditions, and the optimal conditions were obtained. Titanium trichloride was used to deal the grinding debris of the completed degreasing oil, and then analyzed by atomic absorption spectroscopy to determine the composition of the total iron. The experimental results show that using the oven drying method directly, using solvents, and alkaline cleaners were excellent degreasing effect obtained. The grinding debris contain about 50% total iron was obtained after degreasing treatment. It can be utilized to re-use.
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Hottenstein, Aaron. « A Spatiotemporal And Geochemical Evaluation Of Groundwater Quality Adjacent To Natural Gas Drilling And Hydraulic Fracturing In Dimock Township, Susquehanna County, Pennsylvania ». 2014. http://scholarworks.gsu.edu/geosciences_theses/78.
Texte intégralRésumé :
In the Marcellus shale region, elevated concentrations of dissolved methane in private water wells has been shown to be linked to natural gas extraction, but little is known of the connections between methane, gas production, and water chemistry. This study evaluates the relationships of methane to the major chemical constituents of groundwater by comparing analytical data obtained from a stray gas investigation by the Pennsylvania Department of Environmental Protection (PADEP). Furthermore, spatiotemporal relationships of dissolved methane to gas well production and total iron (Fe) concentrations of groundwater to adjacent gas wellheads are examined. The objectives of this study were to identify essential pre- and post-drill test parameters that are sensitive to methane, and to determine what water types are associated with stray gas. It was discovered that total Fe concentrations in groundwater increased and sulfate (SO4) concentrations decreased likely as the result of redox reactions by anaerobic microbes in the presence of stray gas. Therefore, total Fe and SO4 should be mandated pre- and post-drill test parameters for baseline water quality assessments.
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Ammari, Tarek Ghassan [Verfasser]. « Total soluble iron in the soil solution of physically, chemically and biologically different soils / submitted by Tarek Ghassan Ammari ». 2005. http://d-nb.info/97733337X/34.
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Noh, Cheol Hwa. « Comparison of total factor productivity changes between Japan and Korea the cases of the textile industry and the iron and steel industry / ». 1987. http://catalog.hathitrust.org/api/volumes/oclc/21461884.html.
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« Alkaline oxidation of hydrosulfide and methyl mercaptide by iron/cerium oxide-hydroxide in presence of dissolved oxygen. Possible application for removal of Total Reduced Sulfur (TRS) emissions in the Pulp & ; Paper industry ». Thesis, Université Laval, 2007. http://www.theses.ulaval.ca/2007/24330/24330.pdf.
Texte intégral
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Cardoso, Débora Carvalho Meneses Gouveia. « Controlo de gestão no Sector Público. Balanced Scorecard : o caso do IRN, I.P ». Master's thesis, 2018. http://hdl.handle.net/10400.26/23356.
Texte intégralRésumé :
O controlo de gestão tem vindo a assumir cada vez mais um papel crucial nas organizações
públicas. O Balanced Scorecard (BSC) é um dos instrumentos de medição e de gestão do
desempenho mais utilizado mundialmente. Ainda que os seus autores, Kaplan e Norton (1992)
tenham criado este instrumento para as empresas, a flexibilidade e adaptabilidade do BSC tem
permitido a sua aplicação a diversos tipos de organização, incluindo as do setor público e as
sem fins lucrativos (Niven, 2006).
Uma vez que, para além da descrição das tarefas realizadas no estágio, deve ser realizada a sua
análise crítica, a reflexão e investigação realizadas pela estagiária foram conduzidas pelas
seguintes questões: 1) será que o IRN,I.P reúne as condições para a implementação com sucesso
do BSC?; 2) se sim, como permitir a monitorização e implementação do BSC no IRN, I.P.; e
3) será possível implementar um subsistema no BSC associado ao TQM (Total Quality
Management)?. Estas questões de investigação foram construídas a partir da revisão da
literatura científica e em torno dos seguintes tópicos: o controlo de gestão, as possibilidades de
aplicação de modelos e estudos de TQM ao setor público e, especificamente, o BSC enquanto
ferramenta de controlo de gestão e a sua aplicação ao setor público.
Para a concretização empírica deste estudo foi recolhida informação relativa ao controlo de
gestão e implementação do BSC no IRN, I.P. através das seguintes técnicas de recolha de dados:
observação participante, análise de documentos do IRN, I.P., de base BSC e entrevistas
realizadas a responsáveis da organização.
Os principais resultados podem sintetizar-se no contributo da estagiária para a melhoria da
implementação do BSC, no IRN, I.P., como poderosa ferramenta de gestão estratégica
desenvolvendo tarefas que permitem: alinhar iniciativas organizacionais e objetivos
estratégicos da organização, concretizar a monitorização do BSC, mas, principalmente, permitir
que essa monitorização do BSC passe a fomentar o Quadro de Avaliação e Responsabilização
(QUAR) e, por sua vez, o Sistema Integrado de Avaliação de Desempenho da Adminstração
Pública (SIADAP) no sentido da preparação de futuras avaliações à instituição.
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Frimlová, Petra. « Humor a kritika v díle Pantaleón a jeho ženská rota Maria VargaseLlosy ». Master's thesis, 2015. http://www.nusl.cz/ntk/nusl-339890.
Texte intégralRésumé :
OF THE THESIS: The novel Captain Pantoja and the Special Service introduces the second period of Mario Vargas Llosa's literary production, which is caracterized by the simplification of the narration and the discovery of humour. The thesis focuses on the formal and thematic analysis of the novel with the objective to prove that despite the novel is in general humorous and parodic, there could be found some constant topics, known to the readers from Llosa's previous novels, which he had always treated very critically, and he also did so in this erotic and humorous work. Therefore, apart from the analysis of humour the thesis also examines the critical approach to the social problems present in the novel. The analysis also shows that the narration is slightly simplified in comparison to the author's formers works, but it still perfectly demonstrates the unconventional narrative techniques, which Vargas Llosa has used since the 1960's, since the period of the new hispano-american novel. KEY WORDS: Mario Vargas Llosa, Captain Pantoja and the Special Service, The Time of the Hero, The Green House, Latin American boom, Hispano-American new novel, total novel, experimental narrative techniques, types of humour and irony, humorous prose, parody, erotic novel, libertine prose, rainforest, criticism of the...