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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Development Of A Predictive Model For Carbon Dioxide Sequestration In Deep Saline Carbonate Aquifers

Anbar, Sultan 01 June 2009 (has links) (PDF)
Although deep saline aquifers are found in all sedimentary basins and provide very large storage capacities, a little is known about them because they are rarely a target for the exploration. Furthermore, nearly all the experiments and simulations made for CO2 sequestration in deep saline aquifers are related to the sandstone formations. The aim of this study is to create a predictive model to estimate the CO2 storage capacity of the deep saline carbonate aquifers since a little is known about them. To create a predictive model, the variables which affect the CO2 storage capacity and their ranges are determined from published literature data. They are rock properties (porosity, permeability, vertical to horizontal permeability ratio), fluid properties (irreducible water saturation, gas permeability end point, Corey water and gas coefficients), reaction properties (forward and backward reaction rates) and reservoir properties (depth, pressure gradient, temperature gradient, formation dip angle, salinity), diffusion coefficient and Kozeny-Carman Coefficient. Other parameters such as pore volume compressibility and density of brine are calculated from correlations found in literature. To cover all possibilities, Latin Hypercube Space Filling Design is used to construct 100 simulation cases and CMG STARS is used for simulation runs. By using least squares method, a linear correlation is found to calculate CO2 storage capacity of the deep saline carbonate aquifers with a correlation coefficient 0.81 by using variables found from literature and simulation results. Numerical dispersion effects have been considered by increasing the grid dimensions. It has been found that correlation coefficient decreased to 0.77 when the grid size was increased from 250 ft to 750 ft. The sensitivity analysis shows that the most important parameter that affects CO2 storage capacity is depth since the pressure difference between formation pressure and fracture pressure increases with depth. Also, CO2 storage mechanisms are investigated at the end of 300 years of simulation. Most of the gas (up to 90%) injected into formation dissolves into the formation water and negligible amount of CO2 reacts with carbonate. This result is consistent with sensitivity analysis results since the variables affecting the solubility of CO2 in brine have greater affect on storage capacity of aquifers. Dimensionless linear and nonlinear predictive models are constructed to estimate the CO2 storage capacity of all deep saline carbonate aquifers and it is found that the best dimensionless predictive model is linear one independent of bulk volume of the aquifer.
12

Transformation Of Potato With Myb4 Transcription Factor And Evaluation Of Abiotic Stress Tolerance And Gene Expression Profiles In Transgenic Plants

Kalemtas, Gulsum 01 February 2011 (has links) (PDF)
ABSTRACT TRANSFORMATION OF POTATO WITH MYB4 TRANSCRIPTION FACTOR AND EVALUATION OF ABIOTIC STRESS TOLERANCE AND GENE EXPRESSION PROFILES IN TRANSGENIC PLANTS Kalemtas, G&uuml / ls&uuml / m Ph.D., Department of Biology Supervisor: Prof. Dr. H&uuml / seyin Avni &Ouml / ktem February 2011, 257 pages Potato (Solanum tuberosum L. cv. Kennebec) was transformed via Agrobacterium tumefaciens (EHA105) harbouring two different binary vectors containing Oryza sativa myb4 gene, which encodes MYB4 transcription factor / under the control of CaMV35S promoter or cold inducible COR15a promoter. The transgenic plants were not growth retarded and there was no significant difference (p&lt / 0.05) in their tuber yield compared to wild-type plants. Wild-type and transgenic plants were subjected to abiotic stresses to compare their stress tolerances. There was no significant difference in boron, freezing and drought tolerances of wild-type and transgenic lines. Two of the transgenic lines were more salt tolerant than wild-type with respect to growth parameters. Transcriptomes of wild-type and these two lines, one expressing myb4 under the control of 35S promoter and the other COR15a promoter, were analyzed to elucidate the myb4-regulated processes and downstream target genes in potato. Differentially regulated genes in transgenic lines showed that myb4 controls a large and complex transcriptional network associated with diverse cellular processes, primarily defense and rescue, metabolism and development. Genes involved in sucrose synthesis, some peroxidases and CBF3 transcription factor were up-regulated in transgenic plants upon exposure to freezing stress. This suggested that myb4 may configure freezing response in potato primarily by oxidative stress defence mechanisms, osmotic adjustment or activation of CBF3 regulated genes that may confer cold tolerance. Despite up-regulation of these stress related genes, transgenic potato was not more drought or freezing tolerant compared to WT under the tested conditions. Further experiments should be conducted to better elucidate the involvement of these genes in regulation of stress response in transgenic potato expressing myb4.
13

Cleaner Production Opportunity Assessment For Market Milk Production In Ataturk Orman Ciftligi (aoc) Facility

Ozbay, Arzu 01 December 2003 (has links) (PDF)
In this study, possible cleaner production opportunities for a dairy processing facility are examined, considering the market milk production process. Cleaner production concept and its key tools of implementation were analyzed to build the basis of study. General production process and its resulting environmental loads are discussed by taking possible CP opportunities as the axis of study. A methodology is developed for cleaner production opportunity assessment in Milk Processing Facility of Atat&uuml / rk Orman Ciftligi. The methodology covers two major steps / preparation of checklists for assisting auditing and opportunity assessment / implementation of the mass balance analysis. For mass balance analysis, measurements and experimental analysis of the mass flows are utilized to determine the inputs and outputs. Prepared check lists are utilized to determine waste reduction options that could be implemented. Selected opportunities are evaluated considering its environmental benefits and economic feasibility.
14

Utilization Of Waste Materials From Iron-steel And Zinc Industries For Sorption Of Hydrogen Sulfide At High Concentrations

Harmanci, Ebru 01 July 2004 (has links) (PDF)
The slags from iron-steel and zinc industries are rich in metal oxide contents like FeO, MnO, CaO. However, these slags are not used extensively, except some usage in the cement industry. These slags can be used in removing H2S from waste gases from different industrial sources. The purpose of this research is to study the effect of initial concentration of H2S on the capacity and sorbent efficiency of waste materials from iron-steel and zinc industries. Experiments were conducted in a 25 mm-quartz reactor with simulated gases containing H2S as reactive gas. Breakthrough curves for sulfidation reactions were obtained for 3000 ppmv, 4000 ppmv and 5000 ppmv initial H2S concentrations at the reaction temperature range of 500&deg / C&ndash / 700&deg / C. According to the results obtained from the experiments, the H2S removal capacity of both slags increased with increasing reaction temperature, however, the H2S removal capacity of the slags decreases as the initial H2S concentration increases. Cyclic sulfidation and regeneration tests were applied to both steel and zinc slags in order to determine the regenerability of the slags. In cyclic tests, zinc slag gave better results than steel slag. A &ldquo / Deactivation Model&rdquo / was used in order to fit the breakthrough curves obtained experimentally to the breakthrough curves predicted from the deactivation model. A very good fit was obtained for both steel and zinc slags. Zinc slag was shown to be more suitable for gas cleanup than steel slag taking into account its high H2S removal efficiency, regenerability and low cost (almost free of charge).
15

One king to rule them all : identidade, legitimação e unidade na versão Alfrediana da Consolação da Filosofia (Séc. IX - X)

Pereira, Monah Nascimento January 2016 (has links)
Orientadora : Profª. Drª. Fátima Regina Fernandes / Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Humanas, Programa de Pós-Graduação em História. Defesa: Curitiba, 06/07/2016 / Inclui referências : f. 89-92 / Resumo: No final do século IX inicia-se o que se convencionou chamar de período alfrediano na Inglaterra anglo-saxônica. Este configurou-se a partir de alguns fatores essenciais, a citar a necessidade de luta por sobrevivência do reino de Wessex ante aos invasores vikings, bem como o processo de resgate cultural e espiritual que marcou o reinado de Alfred, o Grande (871-899). Nesse contexto, reconhecidas obras da patrística cristã foram traduzidas do latim para o inglês antigo, numa conjuntura de mudanças sociais e culturais que eram construídas e legitimadas a partir de uma tradição reconhecida. A De Consolatione Philosophiae, escrita originalmente por Boécio no século VI, é uma obra caráter filosófico e literário, na qual são discutidas questões como a verdadeira felicidade, a sabedoria, o livre arbítrio e o destino mutável (wyrd). A versão alfrediana da mesma traz uma série de mudanças e adições, que visam atualizar o discurso autorizado de Boécio, adaptando-a às necessidades e expectativas do momento histórico vivido. Nossas chaves interpretativas para estudo de tal temática advém de uma linha historiográfica representada por pesquisadores como David Pratt e Nicole Discenza, os quais não apenas procuram observar as questões filosóficas presentes na obra alfrediana, mas sim analisar a relação entre esta e um contexto de mudanças no cenário político e cultural da Inglaterra medieval, o qual encaminha-se para a unificação inglesa do século X. Assim, procuraremos entender a própria identificação da obra em seu contexto, analisando as formas de abstração utilizadas na época para explicação da sociedade e, consequentemente, legitimação de uma prática real que está se construindo. Nosso objetivo é compreender o modo como as noções de história, unidade e providência presentes no texto contribuem para a criação de um ideal de identidade calcado na religião e na tradição latino cristã, o qual, em última instancia, fortalece um conceito de unidade do reino que começa a ser forjado a partir de Alfred. Palavras-chave: Inglaterra anglo-saxônica; Alfred; Legitimação / Abstract: At the end of the ninth century what historians have named as Alfredian period begins in Anglo-Saxon England. The main characteristics of such period are built upon essential factors, including the struggle for survival of the kingdom of Wessex facing Viking invaders, and the process of cultural and spiritual revival that marked the reign of Alfred the Great (871-899). In this context, recognized works of Christian Patristic were translated from Latin to Old English, in an environment of social and cultural changes that were constructed and legitimated based on a recognized tradition. De Consolatione Philosophiae, originally written by Boethius in the sixth century, is a philosophical and literary work, in which issues such as true happiness, wisdom, free will and the mutating fate (wyrd) are discussed. The Alfredian version of it brings a number of changes and additions, which aim to update the authorized speech by Boethius, adapting it to the needs and expectations of the historical moment. Our interpretive keys to study this theme come from a historiographical line represented by researchers like David Pratt and Nicole Discenza, which seek not only to observe philosophical issues presented in the Alfredian work, but to analyze the relation between this and the context of changes in the political and cultural landscape of medieval England, which is heading towards the English unification of the tenth century. Thus, we seek to understand the work identifying it in its context, analyzing the forms of abstraction used at the time for explanation of society and, consequently, legitimation of a royal practice that is being built. Our goal is to understand how the sense of history, unity and providence in the text contributes to the creation of an identity ideal based on religion and Christian Latin tradition, which ends up strengthening the concept of unity of the kingdom, which begins to be forged from Alfred onwards. Keywords: Anglo-Saxon England; Alfred; Legitimation
16

Authorship, Content and Intention in the West Saxon Consolation of Philosophy

Painter, William Ernest 08 1900 (has links)
Boethius, a late Roman philosopher, composed his last work, De Consolatione Philosophiae, while in prison. His final effort crowned a lifetime of philosophical achievement, and the work was influential throughout the Middle Ages. Frequently translated, the Consolation was one of the books which was chosen by Alfred, a ninth century Anglo-Saxon king, for use in the rebuilding of his kingdom after the Danish invasions. Although intended for an audience which was heavily influenced by a lively pagan tradition, the book was re-interpreted during the Carolingian period to conform to a strict Christian standard. Alfred's own interpretation is indicative of this amalgamation of ancient learning in the milieu of an emerging European culture, as well as his own pragmatic personality.
17

Inheritance Of Wood Specific Gravity And Its Genetic Correlation With Growth Traits In Young Pinus Brutia Progenies

Yildirim, Kubilay 01 February 2008 (has links) (PDF)
In long term, to discover the genes responsible for wood production, genetic control of wood specific gravity (WSG) in Pinus brutia Ten. (Turkish red pine) open pollinated Ceyhan progeny trial, which was established with the seeds collected from 168 clones originated from six clonal Turkish red pine seed orchards was studied. Wood samples were taken by destructive sampling during the rouging of this trial at the age of seven. Specifically / (1) to examine the magnitude of family differences and its components for wood specific gravity (WSG) and growth traits (height, diameter and stem volume) / (2) to determine WSG inheritance and its genetic correlation with growth traits / and (3) to estimate breeding values of 168 families for the WSG and to predict genetic gain if selection is based on phenotypic, rouged and genotypic seed orchard by reselecting the best parents with respect to WSG. Differences among the 168 families for mean WSG was large (ranged from 0.35 to 0.44), as indicated by high individual (0.42+0.07) and family mean (0.55+0.03) heritabilities. Family differences and high heritabilities were also observed for all growth traits. Genetic correlations between WSG and growth traits were statistically insignificant (near zero), while low and insignificant negative phenotypic correlations among the same traits were observed. Realized genetic gain for single trait selection at age seven was insignificant (0.37 %) for WSG and 8.4 % for stem volume in phenotypic seed orchards. Average genetic gain in breeding zone after roguing, by leaving the best 20 clones in each seed orchard, reached 1.7 % for WSG and 16.1 % for stem volume. Genetic gain (relative to controls) at the age of seven obtained from the first generation genotypic seed orchards consisting the best 30 clones was estimated 5.2 % for WSG and 35 % for stem volume. Multi-trait selection was also proposed in this study for the same traits. Selection of best 10 families for the highest WSG and stem volume breeding values produce 5.6 % genetic gain for WSG and 27.7 % genetic gain for stem volume. For the future, the 168 families with known phenotypic and genotypic values regarding to WSG will be screened for the genes responsible for wood production.
18

Assessment Of The Best Available Wastewater Management Techniques For A Textile Mill: Cost And Benefit Analysis

Dogan, Bugce 01 September 2008 (has links) (PDF)
The Integrated Pollution Prevention and Control (IPPC) Directive from the European Union strives to achieve a high level of environmental protection by preventing or reducing the pollution emanating from industrial installations directly at the source. The Directive implies that the emission limit values should be set in accordance with each industry&rsquo / s Best Available Techniques (BAT). In the present study, water recovery and wastewater treatability alternatives developed beforehand were evaluated towards the evaluation of BATs for the management of wastewaters from a denim textile mill. For this purpose, an assessment that translates the key environmental aspects into a quantitative measure of environmental performance and also financial analysis were performed for each of the alternatives. The alternatives considered for water recovery from dyeing wastewaters were nanofiltration (NF) with coagulation and/or microfiltration (MF) pretreatment, ozonation or peroxone and Fenton oxidation. On the other hand, for the end-of-pipe treatment of the mill&rsquo / s mixed wastewater / ozonation, Fenton oxidation, membrane bioreactor (MBR) and activated sludge process followed by membrane filtration technologies were evaluated. The results have indicated that membrane filtration process providing 70 % water recovery with the least environmental impacts is the BAT for water recovery. On the other side, MBR technology has appeared as the BAT for the end-of-pipe treatment of the mill&rsquo / s mixed wastewater. A technical and financial comparison of these two BAT alternatives revealed that water recovery via membrane filtration from dyeing wastewaters is selected as the BAT for the water and wastewater management in the mill.
19

Effect Of Salt Stress On Antioxidant Defense Systems Of Sensitive And Resistant Cultivars Of Lentil (lens Culinaris M.)

Cicerali, Isin Nur 01 July 2004 (has links) (PDF)
ABSTRACT EFFECT OF SALT STRESS ON ANTIOXIDANT DEFENSE SYSTEMS OF SENSITIVE AND RESISTANT CULTIVARS OF LENTIL Cicerali, Iin Nur M.Sc., Department of Biotechnology Supervisor: Prof. Dr. Meral Y&uuml / cel Co-supervisor: Asst. Prof. Dr. F&uuml / sun (nci) Eyidoan June 2004, 90 pages In this study, two lentil cultivars (Lens culinaris, Medik.) (ILL5582-salt tolerant and ILL590) were characterized and compared due to their NaCl susceptibility and antioxidant mechanism was examined under laboratory conditions. Physiological parameters such as wet-dry weight, root-shoot lengths, cell membrane stability, lipid peroxidation in terms of malondialdehyde (MDA), H2O2, proline contents were determined. The activities of antioxidant enzymes such as superoxide dismutase (SOD: EC 1.15.1.1), catalase (CAT: EC 1.11.1.6), ascorbate peroxidase (APX: EC 1.11.1.11) and glutathione reductase (GR: EC 1.6.4.2) were examined and analyzed in 14 days old plant seedlings after 9 days of normal growth and 5 days of 100mM and 200mM NaCl stress conditions. Shoot-root length and wet-dry weight percent decrease were more in ILL590. Especially shoot tissues were affected more from the stress conditions when compared to root tissues. ii According to malondialdehyde (MDA) content and membrane stability results, lipid peoxidation was higher in ILL590 and significant increases were observed in shoot tissues. Proline concentration showed a remarkable increase in salt concentration dependent manner. Higher concentrations of proline in ILL5582 might be the reason of higher salt tolerance when compared to ILL590. Among the antioxidant enzymes SOD was the one which showed highest activity increase. At organ level roots showed highest activity when compared to leaves. In the organelle higher activity percent contribution was achieved by cytosolic Cu/ZnSOD isozyme. Higher percent increase of this isozyme was observed in ILL5582. This might be one of the tolerance mechanisms that get activated against NaCl stress. APX activity showed similar alterations in both cultivars. In leaf tissues significant increase was observed but in root tissues ascorbate peroxidase activity did not change significantly. Glutathione Reductase activity increase was significant in both cultivars leaf tissues but although ILL5582 showed a stress concentration dependent increase, ILL590 did not. The activity of CAT enzyme in leaf and root tissues of both cultivars did not significantly change under increasing salt stress conditions. The results suggested that the leaves were more susceptible to salt stress. Also when two cultivars were compared ILL5582 was found to be more tolerant against salt stress than ILL590 under laboratory conditions and SOD enzyme seemed to be the most active component of the salt tolerant mechanism.
20

An English translation of the Hikayat Abdullah and a critical examination of the subject-matter for the light it may throw on the history of the Far East, 1800-50

Hill, A. H. January 1955 (has links)
No description available.

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