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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.
1

Varietal Loblolly (Pinus Taeda L.) Response to Various Management Schemes and Comparison among Genetic Improvement Levels

Herrin, Billy Landis 11 August 2012 (has links)
Increased growth rates, wood quality, and disease resistance have been accomplished within loblolly pine (Pinus taeda L.) through genetic selection and improved management practices. Genetic engineering of trees has the potential to further improve these selections but also needs to be tested. Two studies were conducted. Study one compares three levels of genetic improvement: Mass-Control Pollinated (MCP), Second Generation Op (2nd gen), and Varietal Material. After three years the MCP material had larger mean heights, mean diameters, and mean volume than the other two genetic entities. However the top five performing varietals were about 0.5 feet taller than the MCP material. Study two tested two contrasting loblolly pine ideotypes across different spacings and management intensities. After two years the crop tree ideotype and the intensive management plots had larger mean heights, mean ground-line diameters, mean volumes, and mean crown widths. Mean branch angle differed significantly between the two crown ideotypes.
2

INVESTIGATION OF PHANEROCHAETE CHRYSOSPORIUM AND CLOSTRIDIUM THERMOCELLUM FOR IMPROVED SACCHARIFICATION OF LIGNOCELLULOSE UNDER NONSTERILE CONDITIONS

Simon, William E. 01 January 2015 (has links)
Current research efforts are directed at developing competitive processes that can utilize lignocellulose as a feedstock for biorefineries. The purpose of this study was to investigate methods of processing lignocellulosic material so that its monosacharides can be more easily accessed for fermentation, the lack of which is hindering the economics and widescale adoption of lignocellulosic biorefining. The monosaccharides are of interest because they can be used by Clostridium beijerinckii downstream of P. chrysosporium and C. thermocellum in a sequential bioprocess to produce butanol. Butanol is an attractive biofuel because it can be utilized without modifying current transportation infrastructure. Butanol is also used as a starting material in organic synthesis. In the first study, the potential for C. thermocellum' s (ATCC 27405) cellulase system to operate outside its optimal temperature range in a high-solids environments was assessed by quantification of the fermentation products lactate, acetate, and ethanol and by quantification of xylose, glucose, and cellobiose remaining. Additionally, the lignin degrading white-rot fungus Phanerochaete chrysosporium RP 78 was investigated as a potential pretreatment for lignocellulose. Elevated temperatures required for Clostridium thermocellum fermentation were examined as a means to improve poor competiveness that is characteristic of P. chrysosporium on unsterile corn stover substrate.
3

Elimination par adsorption sélective du phénol pour la purification des biocarburants de 2ème génération / Elimination of phenol by selective adsorption for the purification of the 2nd generation biofuels

Khalil, Ibrahim 25 October 2018 (has links)
Ce travail s’intéresse à l’étude de l’adsorption sélective du phénol dans des solutions d’hydrocarbures pour la purification des biocarburants issus de la biomasse de la 2ème génération. L’objectif de ce travail est de proposer, à l’aide d’une approche expérimentale et théorique, un adsorbant présentant à la fois une grande capacité d’adsorption du phénol, une sélectivité envers le phénol même en présence d’autres composés aromatiques ainsi qu’un bon pouvoir régénératif dans des conditions douces.Plusieurs familles d’adsorbants sont étudiées : des zéolithes Y et USY avec différents cations de compensation de charge (H+ et Na+) et différentes proportions de la surface micro et de mésoporeuse, des solides siliciques ayant des variables teneurs en groupement silanols et du charbon actif comme solide de référence. Les résultats d’adsorption montrent que dans les micropores des zéolithes, le phénol « interne » peut s’adsorber au nombre de 2 à 4 molécules par supercage, sans pouvoir entrer dans les cages sodalites. Dans la surface mésoporeuse des zéolithes USY et des solides siliciques, la quantité de phénol « externe » adsorbée dépend de la densité des silanols. En présence de toluène dans le mélange, les sites acides montrent une sélectivité importante envers l’adsorption du phénol, cette sélectivité est justifiée par une énergie d’interaction du phénol supérieure à celle du toluène sur ces sites. En revanche, l’adsorption du phénol sur le Na+ et les groupements silanols est affectée respectivement par la présence de faibles et de hautes teneurs en toluène. L’étude de la capacité de régénération des adsorbants met en évidence que les espèces phénoliques fortement liées sont formées sur les sites acides des zéolithes Y (H+Y, Na+Y et USY).Le meilleur compromis en termes de capacité d’adsorption de phénol, de sélectivité et de pouvoir régénératif est obtenu sur la zéolithe H+Y présentant un rapport Si/Al de 2,9. / This work focuses on the study of the selective adsorption of phenol from hydrocarbon solutions for the purification of 2nd generation biofuels. The objective of this work is to propose, using experimental and theoretical approaches, an adsorbent that can gather a good adsorption capacity of phenol, a selectivity towards phenol even in the presence of other aromatic compounds as well as good regeneration capacity under mild conditions.Several adsorbents were studied: Y and USY zeolites with different cations (H+ and Na+) and different proportions of micro and mesoporous surfaces, silica based solids presenting variable amount of silanol group and charcoal as a reference. The adsorption results show that, in the microporous of zeolites, the "internal" phenol can be adsorb to the number of 2 to 4 molecules per supercage, without being able to enter in the sodalite cages. In the mesoporous surface of the USY zeolites and the silica based solids, the amount of adsorbed "external" phenol depends on the density of the silanol groups. In the presence of toluene in the mixture, the acidic sites show a high selectivity towards phenol adsorption, this selectivity is justified by a higher interaction energy of phenol than toluene over these sites. Whereas, the adsorption of phenol over Na+ cation and over the silanol groups was respectively affected at low and high toluene levels. The study of the regeneration capacity of the adsorbents shows that the strongly bounded phenolic species are formed on the acidic sites of Y zeolites (H+Y, Na+Y and USY).The best compromise in terms of phenol adsorption capacity, selectivity and regeneration ability was obtained over the H+Y zeolite presenting a Si/Al ratio of 2.9.
4

An Impractical Agenda for the 2nd Generation of Qualitative Communication Researchers

Herrmann, Andrew F. 16 November 2012 (has links)
No description available.
5

Realisation av allmännyttan? : Analys av kommunala och privata avyttringar av bostadshyresfastigheter

Petré, Ingel, Larsson, Gabrielle January 2011 (has links)
Avyttringen och ombildningen av kommunala och privata bostadshyresfastigheter till bostadsrättsföreningar har blivit ett allt vanligare fenomen under de senaste decennierna. Främst sker avyttringen i Stockholms kommun. Syftet med denna uppsats är att mäta om prissättningen vid utförsäljning av bostadshyresfastigheter inom Stockholms kommun skiljer sig beroende på om säljaren varit privat eller ett allmännyttigt kommunalt bolag. För att undersöka detta har olika regressionsmodeller applicerats på data över fastighetsprisregistret under två mandatperioder. Resultatet visar en tydlig prisskillnad mellan kommunala avyttringar och privata inom samma områdesindelning. Skillnaden i prissättning innebär att kommunala fastighetsbolag har realiserat ut och omfördelat skattebetalarnas pengar, till ett värde som kan uppgå till så mycket som 3,23 miljarder kronor räknat i 2010 års penningvärde. Sannolikt är en sådan förmögenhetsomfördelning inte samhällsekonomisk effektiv. Vidare torde den motverka syftet med hyreslagsstiftningen. / In the Swedish market for multi-family housing, investment properties are often sold to the tenants who thus convert the property into co-operative housing. This is particularly true in attractive housing location where the existing rent control is in practice binding for all residential rental units. It is somewhat less self-evident that multi-family properties owned by the municipality (not-for-profit, council housing) would also be subject to such conversions. This is, however, quite common, particularly in Stockholm. The aim of this paper is to estimate whether council housing is generally sold to the tenants with a discount, as compared to the market prices of transactions where private property companies sell their properties. We use regression techniques applied to data from the official record of real property transactions. We find a significant price difference between the two categories of transactions. Council housing is sold out at a discount price and we estimate that a total value of some 3.23 billion SEK may have been redistributed from the taxpayers to the housing purchasers in these transactions. This program is probably not efficient from a public economic perspective. Furthermore, it counteracts the purpose of the current rent control legislation.
6

Pesquisa orientada a resultado: proposta de um método estruturado para disponibilizar uma nova tecnologia para o mercado: um caso aplicado ao projeto etanol de 2ª geração

Godoy Neto, Oswaldo 12 June 2012 (has links)
Submitted by Oswaldo Godoy Neto (godoyon@gmail.com) on 2012-06-21T22:24:06Z No. of bitstreams: 1 OGN_Pesquisa Orientada a Resultado.pdf: 2716138 bytes, checksum: f337c60cf400c790eb16af14317e34eb (MD5) / Approved for entry into archive by Gisele Isaura Hannickel (gisele.hannickel@fgv.br) on 2012-06-22T12:03:42Z (GMT) No. of bitstreams: 1 OGN_Pesquisa Orientada a Resultado.pdf: 2716138 bytes, checksum: f337c60cf400c790eb16af14317e34eb (MD5) / Made available in DSpace on 2012-06-22T13:03:03Z (GMT). No. of bitstreams: 1 OGN_Pesquisa Orientada a Resultado.pdf: 2716138 bytes, checksum: f337c60cf400c790eb16af14317e34eb (MD5) Previous issue date: 2012-06-12 / Esta dissertação de mestrado teve como objetivo principal propor um método estruturado suportado for ferramentas gerenciais que permitisse orientar e sistematizar o desenvolvimento de um projeto de pesquisa na disponibilização de uma nova tecnologia para o mercado. O 'Projeto Etanol de 2ª Geração', etanol produzido a partir de biomassas lignocelulósicas, aqui selecionado para estudo de caso, foi extraído da carteira de projetos do Centro de Tecnologia Canavieira (CTC). O método estruturado sugerido é constituído, fundamentalmente, por oito requisitos arranjados de forma cronológica ao longo do desenvolvimento do projeto, que visam auxiliar na prospecção, entendimento, avaliação, valoração, priorização, planejamento e implantação de, por exemplo, uma tecnologia inovadora, otimizando tempo, capital e recursos humanos aplicados. Um dos principais pontos do método proposto refere-se à escolha adequada das ferramentas gerenciais a serem utilizadas em cada requisito (brainstorm, análise de patentes, painel de especialistas, análise SWOT, dentre outras). O êxito na aplicação do método requer o entendimento de todos os (potenciais) efeitos, inclusive os colaterais, no processo como um todo. Ou seja, uma vez que toda ferramenta gerencial apresenta pontos fortes e fracos, o importante é adaptá-las ao sistema de negócio e não vice-versa. A partir do gerenciamento do projeto por um gestor com domínio das ferramentas gerenciais, a escolha destas ocorre de forma dinâmica, onde a cada passo de avaliação novas ferramentas (simples e/ou complexas) podem ser incluídas ou excluídas da matriz do método. Neste trabalho ficou demonstrada a importância de se trabalhar com métodos estruturados e flexíveis, que permitem retroalimentação de informações geradas internamente durante o desenvolvimento da pesquisa ou advindas de fontes externas. O projeto Etanol de 2ª Geração do CTC vem aplicando o método proposto em seu desenvolvimento e obtendo grande êxito em seus resultados, uma vez que a equipe envolvida permanece focada no objetivo principal, obedecendo prazos e recursos inicialmente definidos, com constância do propósito do projeto, sem retrocesso ou recomeço. / The objective of this work was to propose a method, structured and supported by management tools, to guide and systematize the development of a project of research focusing to deploy a new technology in the market. The '2nd Generation Ethanol Project', ethanol produced from lignocellulosic biomass, was selected as case study from the portfolio of projects of the Sugarcane Technology Center. Fundamentally, the suggested structured method consists of eight requirements arranged in a chronological order throughout the project development cycle, aiming at assisting the exploration, understanding, evaluation, assessment, prioritization, planning and deployment of, for example, an innovative technology, optimizing the applied time and capital and human resources. One of the main points of the proposed method refers to the adequate choice of the management tools to be used in each requirement (brainstorm, patent analysis, expert panel, SWOT analysis, among others). The successful application of the method requires the understanding of all (potential) effects, including the side effects, in the whole process. Since all management tools have strong and weak points, the most important thing is to adapt them to the business system and not vice versa. Considering that the project should be conducted by a person with some knowledge and skilled on this area, the choice of the tools happens in a very dynamic way, where after each assessment, new tools (simple and/or complex) may be included or excluded from the method matrix. In this work it was demonstrated the importance of working with structured and flexible methods which accept retrofitting of information generated along the research development or that comes from external sources. The 2nd Generation Ethanol Project has internally used the proposed method and obtained good results, since with this approach it was possible to keep the team focused on the same main goal, obeying the planned schedule with the resources initially defined, with no rewind or restart.
7

Hledání cesty ke kořenům: jazykový a sociokulturní management mladých Vietnamců v České republice / Back to our Roots: Language and Sociocultural Management of Young Vietnamese in the Czech Republic

Ngo, Quynh Nga January 2016 (has links)
A common phenomenon among migrants is called language attrition, or the partial loss of language skills caused by changes in the active use of the language. This phenomenon occurs in the Czech Republic, where numerous young Vietnamese are often praised (especially by teachers) for their quick acquisition of the Czech language in the school environment, but experience shortcomings in their Vietnamese language and socio-cultural competence during early adulthood, on the basis of which they begin to go "back to their roots." The main topics of research in this thesis are 1) the experience of loss of the Vietnamese language and socio-cultural competence by individual Vietnamese and by the Vietnamese community in the Czech Republic, 2) adjustment designs to remedy these deficiencies and 3) the (non-)implementation of these adjustment designs by both individuals and organizations in the Czech Republic. The theoretical- methodological framework is a Language Management Theory (Neustupný 2002) and the main methodological approaches are language biography (Nekvapil 2004) and ethnography. The results of the analysis indicate the critical points to be addressed in incentives for Vietnamese language teaching methodology for young Vietnamese, as well as in the experience and reflection of their personal identities.
8

Gasoline‐Ethanol‐Methanol (GEM) Ternary Fuel Blend as an Alternative Passenger Car Fuel in Sweden

Tsirakos, Sebastiaan Nikolas January 2017 (has links)
This paper discusses the potential of gasoline, ethanol and methanol ternary blend as an alternative passenger car fuel in Sweden. Sweden has set various targets aimed to reduce its GHG emissions and to increase the share of renewables in the transportation sector. Nevertheless, the majority of the energy consumed in the road transportation sector still comes from fossil fuels. In order to replace the energy supply of fossil fuels by more renewable fuels, the potential of alternative renewable fuels needs to be explored. Therefore, the potential of a domestically produced ternary blend of Gasoline‐Ethanol‐ Methanol (GEM) fuel blend is analysed in this report. In order to test whether it has the potential to become a successful alternative fuel, an analysis is performed on the: methanol and ethanol production potential from domestic second‐generation feedstocks, the selection of the most suitable production pathways of the biofuels, the potential for a Swedish GEM fuel distribution infrastructure, the economic competitiveness of GEM fuel, and lastly on the environmental impact of the shift from cars running on neat gasoline to GEM fuel. In order to perform the analysis, two scenarios are developed for projecting the share of the GEM cars(cars running on GEM fuel blends) in the Swedish passenger car fleet, considering a time horizon from 2017 to 2030. In Scenario 1, a high share of passenger cars running on GEM fuel is obtained with 22 percent by 2030. In Scenario 2, a low share of cars running on GEM fuel is obtained with 17 percent by 2030. In both scenarios, the passenger cars running on GEM fuel take over the share of cars running on gasoline. The scenarios serve to project the energy demand for GEM fuels. By 2030, the projected energy demand for GEM fuels is 9.7 and 7.5 TWh for Scenario 1 and Scenario 2, respectively. From the biofuel potential studies, it can be concluded that the production potential of the alcohol fuels, derived from currently untapped domestic secondary resources, exceeds the projected energy demand of 9.7 and 7.5 TWh in 2030. According to this thesis, the production potential of 2nd generation ethanol and methanol are 36 and 61.1 TWh, respectively, by 2030. Moreover, the study shows that the majority of the existing fuel distribution network of E85 and gasoline, which is forecasted to have a significant overcapacity in the same time‐span as the scenarios, can be utilized in a GEM fuel distribution network. As a consequence, no major investments are required to develop a Swedish GEM fuel distribution network. Regarding the selection of the biofuel production pathways, this study indicates the most suitable way of producing methanol is by black‐liquor gasification. Regarding second‐generation ethanol, this thesis indicates that the fermentation forestry residues is the most beneficial production pathway. The biofuel production pathways are selected based on the energy yield ratios, the biofuel production cost and biomass feedstock cost. Moreover, this study demonstrates that under the current Swedish policies, GEM fuels blends are economic competitive with gasoline and E85. In order to test the economic competitiveness, a pay‐off curve was developed based on the pump price of gasoline and fuel economy of GEM fuel blends. This study shows the pump prices of GEM fuel blends pay‐off in comparison to gasoline. This analysis indicates that the pump prices of GEM fuel blends lays between 0.87 and 0.92 euro per liter. Regarding the environmental impact, this study indicates that the amount of GHG emissions avoided varies between 10.1 and 13.3 million metric tons CO2eq in Scenario 1. In Scenario 2, the amount of GHG emissions that can be avoided varies between 8.6 and 11.3 million metric tons CO2eq. Moreover, this study indicates that high methanol containing GEM fuel blend are more favourable in terms of biomass utilization, and high ethanol containing GEM fuel blends are more favourable in terms of economy and GHG savings.
9

Grassroots Canadian Muslim Identity in the Prairie City of Winnipeg: A Case Study of 2nd and 1.5 Generation Canadian Muslims

Hameed, Qamer January 2015 (has links)
What are grassroots “Canadian Muslims” and why not use the descriptor “Muslims in Canada”? This thesis examines the novel concept of locale specific grassroots Canadian Muslim identity of second and 1.5 generation Muslims in the prairie city of Winnipeg, Manitoba. The project focuses on a generation of Muslims that are settled, embedded, and active in a medium sized Canadian metropolis. Locale plays a powerful part in the way people navigate identities, form attachments, find belonging, and negotiate communities and society. In order to explore this unique identity a case study was conducted in Winnipeg. Interviews with 1.5 and second generation Muslims explored the experience of grassroots Canadian Muslim identity. The project does not focus on religious doxy or praxis but rather tries to understand a lived Canadian Muslim identity by exploring discourse and space as well as strategies, social perceptions and expectations. Participant observation, community resources and literature also aid in the understanding of the grassroots Canadian Muslim experience. This study found that the attachments, networks, and experiences in the locale give room for an embedded Canadian Muslim experience and more negotiable identities than most studies on Muslims in Canada describe. These individuals are not foreigners living in Canada. Their worldviews develop out of this particular and embedded grassroots experience. They navigate a new kind of hybrid Canadian Muslim identity that is unique and flexible. This is the Canadian Muslim experience of 2nd and 1.5 generation Winnipeg Muslims.

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