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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.
151

Uso de marcadores orgânicos moleculares na determinação da origem da matéria orgânica em sedimentos do Sistema Estuarino-Lagunar de Cananéia-Iguape - SP - Brasil / Use of organic molecular markers in determination of the origin of the organic matter of Estuarine-Lagunar System of Cananeia-Iguape

Senatore, Diego Barbosa 30 April 2010 (has links)
Este trabalho tem como objetivo estudar as fontes de matéria orgânica em sedimentos ao longo do Sistema Estuarino-Lagunar de Cananéia-Iguape, por meio de diferentes indicadores geoquímicos. Foram coletados 12 testemunhos. Os 10 centímetros superficiais foram fatiados de 2 em 2 centímetros, totalizando 60 amostras. Análises granulométricas, de razão C/N, 13C/12C e a datação de alguns dos testemunhos, foram feitos pelo grupo de Oceanografia Geológica do IOUSP. Os marcadores orgânicos moleculares utilizados foram os hidrocarbonetos alifáticos, álcoois graxos e esteróides, analisados por GCFID. O total de hidrocarbonetos alifáticos variou entre 0,571 a 9,932 g g-1. Os álcoois totais variaram de 0,318 a 35,291 g g-1. Os esteróides totais variaram de 0,241 a 11,054 g g-1. Para interpretação dos dados foram utilizadas as razões entre n-alcanos ímpares e pares leves (C21) e pesados (C22), somatório de álcoois graxos leves e pesados, relação entre a soma de coprostanol e epicoprostanol sobre o total de esteróides e relação entre epicoprostanol e coprostanol. Os resultados das razões indicam uma origem terrestre dos compostos orgânicos analisados com uma clara predominância da contribuição da vegetação de manguezal da região. Entretanto, existe uma discreta introdução de hidrocarbonetos de petróleo e esgoto domésticos nãotratados em alguns pontos isolados do Sistema Estuarino-Lagunar de Cananéia-Iguape. / This work has the objective in evaluate the sources of organic matter in sediments of the Cananéia-Iguape Estuarine-Lagunar System, using several geochemical markers. For the study area, 12 sample points were chosen, where the corers were obtained. For each point, the superficial 10 centimeters, sliced in each 2 centimeters, totalizing 60 samples. Granulometric analysis, C/N and 13C/12C ratios and dating of some cores, were realized by the Geological Oceanography group of IOUSP. The molecular organic markers used were the aliphatic hydrocarbons, fatty alcohols and steroids, analyzed by GC-FID. The total hydrocarbons varied from 0.571 to 9.932 g g-1. The total fatty alcohols ranged from 0.318 to 35.291 g g-1. The total steroids varied from 0.241 to 11.054 g g-1. For interpretation of data, some relations were used such as odd/even hydrocarbons C21 and C22, total short and long chain fatty alcohols, the coprostanol + epicoprostanol divided by total sterols and epicoprostanol/coprostanol. The results of the ratios showed a terrestrial origin of the organic matter with a clear predominance of the contribution of the mangrove higher plants of the region. However, there is a discrete introduction of petroleum hydrocarbons and untreated domestic sewage in isolated points of the Estuarine-Lagunar System of Cananéia-Iguape.
152

Paleoenvironments, origin, and relative maturity of organic matter in Barremian-Aptian limestones of the eastern Prada Quarry, Organyà Basin, NE Spain

Llaguno, Jose R 16 November 2017 (has links)
This study is a multi-proxy analysis of a 30-m section of a Barremian-Aptian succession of interbedded, grayish black (N2) and black (N1) limestones from a quarry of the Sierra de Prada. Index taxa include planktic foraminifera Globigerinelloides blowi and Hedbergella sigali, which combined with δ13C data from Cresmina and Gorgo a Cerbara sections indicate a late Barremian to early Aptian age. The rocks are organic-rich with 0.67 - 3.10 wt% total organic carbon (TOC). A marlstone interval (~1m) at 2.24 m has a low bioturbation index (1), TOC ~6.66 wt%, framboidal pyrite, and enrichment spikes of major, biolimiting, and redox-sensitive trace elements (Al, Si, Ti, P, Fe, and Mo, Cr, Cu, V, Th), indicating an anoxic episode. Biomarker analyses show a predominance of n-alkanes (≤nC20) at this level, suggesting an in situ origin of organic matter from phytoplankton. Pr/Phy ratios below 2 imply that organic matter did not reach overmaturity.
153

Structures and Self-Organization at Liquid Crystal Interfaces: Surface Ordering and Anchoring

Feng, Xunda 15 April 2013 (has links)
No description available.
154

Toward green processes organic synthesis by catalysis with metal-doped solids

Borghese, Sophie 15 February 2013 (has links) (PDF)
Nowadays, the modern chemical industry has to deal with increasing environmental concerns, including the disposal of waste and its economic impact, or the diminution of important worldwide resources such as transition metals. In this Ph.D. thesis, we aimed to bring improvement in this area by the development of green processes, based on the use of recyclable heterogeneous catalysts. By combining the catalytic properties of several metal cations with the properties of solid catalysts such as polyoxometalates or zeolites, we were able to set up new tools for organic synthesis. Silver-doped polyoxometalates proved to be very efficient catalysts in the rearrangement of alkynyloxiranes to furans. Acetals and spiroketals were synthetized by dihydroalkoxylation of alkynediols under catalysis with silver-zeolites. As a perspective, we highlighted the potential applications of such green procedures in the total synthesis of more complex molecules. The first results suggested that these environmental friendly processes should gain increasing interest in the future.
155

Practical approaches to improve the value of the Falkland Islands' sheep and wool industry

Miller, Sean Michael Unknown Date (has links)
Studies were conducted to determine basic aspects of intake and digestion of native pastures by young sheep in the Falkland Islands, and to evaluate practical methods to improve the productivity of these animals. The studies were conducted in support of Industry and Government initiatives to reinvigorate Falklands’ agriculture. The current industry is based on broad diameter wools harvested from sheep grazing poor quality native pastures, and sheep suffer low growth rates, poor productivity and high mortality, and farmers rely on small flocks to produce a single commodity for their total income. The dramatic collapse of wool markets in the 1980’s crippled the Falklands’ wool industry and farmers have relied heavily on subsidies for more than 12 years. The studies in this thesis were initiated to support the efforts to reinvigorate Falklands’ agriculture, and they examined basic aspects of the nutrition provided to sheep by native pastures and evaluated practical methods to improve the survival of sheep, their subsequent rate of growth and productive value to the economy. Five studies examined specific hypotheses posed at the outset of the research programme and they were broadly supported by the data presented in the thesis: · A wether trial was used to benchmark the productivity of wool sheep in the Islands, and the trial demonstrated that substantial genetic variation exists within the national flock that may be exploited in the future to improve the productivity of the wool industry, · Microhistological techniques were used in conjunction with n-alkane marker technology to investigate the diets consumed by sheep grazing native pastures. The diet studies concluded that the low quality of native pasture in the Falklands during autumn, winter and spring restricts growth and productivity of young sheep, · Studies with weaner sheep treated with controlled release anthelmintics established that infection with gastrointestinal nematodes exacerbates poor nutrition of young sheep consuming native pastures, · A short-term metabolism study demonstrated that native pasture hay fortified with molasses and urea, or winter forage crops may be used as supplements to enhance sheep productivity, and · Forage crops were grown and evaluated under Falklands’ conditions, and when lambs were fed the resulting highly productive and nutritious forages, the study demonstrated that lamb growth can be increased significantly, and lamb carcasses offer local farmers the potential to diversify farm income by using existing Falklands’-bred lambs to develop an export meat industry The data presented in this thesis demonstrate that the potential to improve the productive and financial position of Falklands’ farmers is substantial. If both the local Industry and Government maintain their joint commitment to industry-restructure, pastoral development and enterprise diversification, the Falklands’ agricultural economy stands to benefit considerably by adopting low risk solutions to address widespread problems.
156

Practical approaches to improve the value of the Falkland Islands' sheep and wool industry

Miller, Sean Michael Unknown Date (has links)
Studies were conducted to determine basic aspects of intake and digestion of native pastures by young sheep in the Falkland Islands, and to evaluate practical methods to improve the productivity of these animals. The studies were conducted in support of Industry and Government initiatives to reinvigorate Falklands’ agriculture. The current industry is based on broad diameter wools harvested from sheep grazing poor quality native pastures, and sheep suffer low growth rates, poor productivity and high mortality, and farmers rely on small flocks to produce a single commodity for their total income. The dramatic collapse of wool markets in the 1980’s crippled the Falklands’ wool industry and farmers have relied heavily on subsidies for more than 12 years. The studies in this thesis were initiated to support the efforts to reinvigorate Falklands’ agriculture, and they examined basic aspects of the nutrition provided to sheep by native pastures and evaluated practical methods to improve the survival of sheep, their subsequent rate of growth and productive value to the economy. Five studies examined specific hypotheses posed at the outset of the research programme and they were broadly supported by the data presented in the thesis: · A wether trial was used to benchmark the productivity of wool sheep in the Islands, and the trial demonstrated that substantial genetic variation exists within the national flock that may be exploited in the future to improve the productivity of the wool industry, · Microhistological techniques were used in conjunction with n-alkane marker technology to investigate the diets consumed by sheep grazing native pastures. The diet studies concluded that the low quality of native pasture in the Falklands during autumn, winter and spring restricts growth and productivity of young sheep, · Studies with weaner sheep treated with controlled release anthelmintics established that infection with gastrointestinal nematodes exacerbates poor nutrition of young sheep consuming native pastures, · A short-term metabolism study demonstrated that native pasture hay fortified with molasses and urea, or winter forage crops may be used as supplements to enhance sheep productivity, and · Forage crops were grown and evaluated under Falklands’ conditions, and when lambs were fed the resulting highly productive and nutritious forages, the study demonstrated that lamb growth can be increased significantly, and lamb carcasses offer local farmers the potential to diversify farm income by using existing Falklands’-bred lambs to develop an export meat industry The data presented in this thesis demonstrate that the potential to improve the productive and financial position of Falklands’ farmers is substantial. If both the local Industry and Government maintain their joint commitment to industry-restructure, pastoral development and enterprise diversification, the Falklands’ agricultural economy stands to benefit considerably by adopting low risk solutions to address widespread problems.
157

Practical approaches to improve the value of the Falkland Islands' sheep and wool industry

Miller, Sean Michael Unknown Date (has links)
Studies were conducted to determine basic aspects of intake and digestion of native pastures by young sheep in the Falkland Islands, and to evaluate practical methods to improve the productivity of these animals. The studies were conducted in support of Industry and Government initiatives to reinvigorate Falklands’ agriculture. The current industry is based on broad diameter wools harvested from sheep grazing poor quality native pastures, and sheep suffer low growth rates, poor productivity and high mortality, and farmers rely on small flocks to produce a single commodity for their total income. The dramatic collapse of wool markets in the 1980’s crippled the Falklands’ wool industry and farmers have relied heavily on subsidies for more than 12 years. The studies in this thesis were initiated to support the efforts to reinvigorate Falklands’ agriculture, and they examined basic aspects of the nutrition provided to sheep by native pastures and evaluated practical methods to improve the survival of sheep, their subsequent rate of growth and productive value to the economy. Five studies examined specific hypotheses posed at the outset of the research programme and they were broadly supported by the data presented in the thesis: · A wether trial was used to benchmark the productivity of wool sheep in the Islands, and the trial demonstrated that substantial genetic variation exists within the national flock that may be exploited in the future to improve the productivity of the wool industry, · Microhistological techniques were used in conjunction with n-alkane marker technology to investigate the diets consumed by sheep grazing native pastures. The diet studies concluded that the low quality of native pasture in the Falklands during autumn, winter and spring restricts growth and productivity of young sheep, · Studies with weaner sheep treated with controlled release anthelmintics established that infection with gastrointestinal nematodes exacerbates poor nutrition of young sheep consuming native pastures, · A short-term metabolism study demonstrated that native pasture hay fortified with molasses and urea, or winter forage crops may be used as supplements to enhance sheep productivity, and · Forage crops were grown and evaluated under Falklands’ conditions, and when lambs were fed the resulting highly productive and nutritious forages, the study demonstrated that lamb growth can be increased significantly, and lamb carcasses offer local farmers the potential to diversify farm income by using existing Falklands’-bred lambs to develop an export meat industry The data presented in this thesis demonstrate that the potential to improve the productive and financial position of Falklands’ farmers is substantial. If both the local Industry and Government maintain their joint commitment to industry-restructure, pastoral development and enterprise diversification, the Falklands’ agricultural economy stands to benefit considerably by adopting low risk solutions to address widespread problems.
158

Practical approaches to improve the value of the Falkland Islands' sheep and wool industry

Miller, Sean Michael Unknown Date (has links)
Studies were conducted to determine basic aspects of intake and digestion of native pastures by young sheep in the Falkland Islands, and to evaluate practical methods to improve the productivity of these animals. The studies were conducted in support of Industry and Government initiatives to reinvigorate Falklands’ agriculture. The current industry is based on broad diameter wools harvested from sheep grazing poor quality native pastures, and sheep suffer low growth rates, poor productivity and high mortality, and farmers rely on small flocks to produce a single commodity for their total income. The dramatic collapse of wool markets in the 1980’s crippled the Falklands’ wool industry and farmers have relied heavily on subsidies for more than 12 years. The studies in this thesis were initiated to support the efforts to reinvigorate Falklands’ agriculture, and they examined basic aspects of the nutrition provided to sheep by native pastures and evaluated practical methods to improve the survival of sheep, their subsequent rate of growth and productive value to the economy. Five studies examined specific hypotheses posed at the outset of the research programme and they were broadly supported by the data presented in the thesis: · A wether trial was used to benchmark the productivity of wool sheep in the Islands, and the trial demonstrated that substantial genetic variation exists within the national flock that may be exploited in the future to improve the productivity of the wool industry, · Microhistological techniques were used in conjunction with n-alkane marker technology to investigate the diets consumed by sheep grazing native pastures. The diet studies concluded that the low quality of native pasture in the Falklands during autumn, winter and spring restricts growth and productivity of young sheep, · Studies with weaner sheep treated with controlled release anthelmintics established that infection with gastrointestinal nematodes exacerbates poor nutrition of young sheep consuming native pastures, · A short-term metabolism study demonstrated that native pasture hay fortified with molasses and urea, or winter forage crops may be used as supplements to enhance sheep productivity, and · Forage crops were grown and evaluated under Falklands’ conditions, and when lambs were fed the resulting highly productive and nutritious forages, the study demonstrated that lamb growth can be increased significantly, and lamb carcasses offer local farmers the potential to diversify farm income by using existing Falklands’-bred lambs to develop an export meat industry The data presented in this thesis demonstrate that the potential to improve the productive and financial position of Falklands’ farmers is substantial. If both the local Industry and Government maintain their joint commitment to industry-restructure, pastoral development and enterprise diversification, the Falklands’ agricultural economy stands to benefit considerably by adopting low risk solutions to address widespread problems.
159

Practical approaches to improve the value of the Falkland Islands' sheep and wool industry

Miller, Sean Michael Unknown Date (has links)
Studies were conducted to determine basic aspects of intake and digestion of native pastures by young sheep in the Falkland Islands, and to evaluate practical methods to improve the productivity of these animals. The studies were conducted in support of Industry and Government initiatives to reinvigorate Falklands’ agriculture. The current industry is based on broad diameter wools harvested from sheep grazing poor quality native pastures, and sheep suffer low growth rates, poor productivity and high mortality, and farmers rely on small flocks to produce a single commodity for their total income. The dramatic collapse of wool markets in the 1980’s crippled the Falklands’ wool industry and farmers have relied heavily on subsidies for more than 12 years. The studies in this thesis were initiated to support the efforts to reinvigorate Falklands’ agriculture, and they examined basic aspects of the nutrition provided to sheep by native pastures and evaluated practical methods to improve the survival of sheep, their subsequent rate of growth and productive value to the economy. Five studies examined specific hypotheses posed at the outset of the research programme and they were broadly supported by the data presented in the thesis: · A wether trial was used to benchmark the productivity of wool sheep in the Islands, and the trial demonstrated that substantial genetic variation exists within the national flock that may be exploited in the future to improve the productivity of the wool industry, · Microhistological techniques were used in conjunction with n-alkane marker technology to investigate the diets consumed by sheep grazing native pastures. The diet studies concluded that the low quality of native pasture in the Falklands during autumn, winter and spring restricts growth and productivity of young sheep, · Studies with weaner sheep treated with controlled release anthelmintics established that infection with gastrointestinal nematodes exacerbates poor nutrition of young sheep consuming native pastures, · A short-term metabolism study demonstrated that native pasture hay fortified with molasses and urea, or winter forage crops may be used as supplements to enhance sheep productivity, and · Forage crops were grown and evaluated under Falklands’ conditions, and when lambs were fed the resulting highly productive and nutritious forages, the study demonstrated that lamb growth can be increased significantly, and lamb carcasses offer local farmers the potential to diversify farm income by using existing Falklands’-bred lambs to develop an export meat industry The data presented in this thesis demonstrate that the potential to improve the productive and financial position of Falklands’ farmers is substantial. If both the local Industry and Government maintain their joint commitment to industry-restructure, pastoral development and enterprise diversification, the Falklands’ agricultural economy stands to benefit considerably by adopting low risk solutions to address widespread problems.
160

Practical approaches to improve the value of the Falkland Islands' sheep and wool industry

Miller, Sean Michael Unknown Date (has links)
Studies were conducted to determine basic aspects of intake and digestion of native pastures by young sheep in the Falkland Islands, and to evaluate practical methods to improve the productivity of these animals. The studies were conducted in support of Industry and Government initiatives to reinvigorate Falklands’ agriculture. The current industry is based on broad diameter wools harvested from sheep grazing poor quality native pastures, and sheep suffer low growth rates, poor productivity and high mortality, and farmers rely on small flocks to produce a single commodity for their total income. The dramatic collapse of wool markets in the 1980’s crippled the Falklands’ wool industry and farmers have relied heavily on subsidies for more than 12 years. The studies in this thesis were initiated to support the efforts to reinvigorate Falklands’ agriculture, and they examined basic aspects of the nutrition provided to sheep by native pastures and evaluated practical methods to improve the survival of sheep, their subsequent rate of growth and productive value to the economy. Five studies examined specific hypotheses posed at the outset of the research programme and they were broadly supported by the data presented in the thesis: · A wether trial was used to benchmark the productivity of wool sheep in the Islands, and the trial demonstrated that substantial genetic variation exists within the national flock that may be exploited in the future to improve the productivity of the wool industry, · Microhistological techniques were used in conjunction with n-alkane marker technology to investigate the diets consumed by sheep grazing native pastures. The diet studies concluded that the low quality of native pasture in the Falklands during autumn, winter and spring restricts growth and productivity of young sheep, · Studies with weaner sheep treated with controlled release anthelmintics established that infection with gastrointestinal nematodes exacerbates poor nutrition of young sheep consuming native pastures, · A short-term metabolism study demonstrated that native pasture hay fortified with molasses and urea, or winter forage crops may be used as supplements to enhance sheep productivity, and · Forage crops were grown and evaluated under Falklands’ conditions, and when lambs were fed the resulting highly productive and nutritious forages, the study demonstrated that lamb growth can be increased significantly, and lamb carcasses offer local farmers the potential to diversify farm income by using existing Falklands’-bred lambs to develop an export meat industry The data presented in this thesis demonstrate that the potential to improve the productive and financial position of Falklands’ farmers is substantial. If both the local Industry and Government maintain their joint commitment to industry-restructure, pastoral development and enterprise diversification, the Falklands’ agricultural economy stands to benefit considerably by adopting low risk solutions to address widespread problems.

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