A dissertation submitted in fulfillment of the requirements for the degree of Master of Science in Physics at the University of the Witwatersrand. November 7th, 2016 / The spin-1=2 Kondo model describes an antiferromagnetic exchange interaction between an impurity spin and the spin-density of a Fermi gas. Although the thermodynamics of this system have been resolved, there are still some unanswered questions regarding its spatial features. The spatial region of correlation between the impurity spin and the spin-density of the Fermi gas is referred to as the Kondo screening cloud. For the case of anisotropic couplings, the cloud consists of four distinct components. In this dissertation we use the bosonization technique to derive both an exact numeric and an approximate analytic expression for the forward scattering longitudinal cloud at the Toulouse point. The expressions are then extended to incorporate the effects of a time-independent external magnetic field. The non-magnetic case displays universal scaling behavior, while the addition of an external magnetic field only slightly spoils the scaling in the vicinity of the crossover length (B) K , but remarkably not deep inside or outside the cloud. / MT2017

Thesis is submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Faculty of Engineering and the Built Environment, School of Mechanical, Industrial and Aeronautical Engineering, University of the Witwatersrand, Johannesburg, 2017 / Porous structures are increasingly becoming important engineering materials in aerospace, health, cooling of electronics, and several other areas. However, the supply of porous structures in these areas is still not being met because the conventional methods of manufacturing porous structures lack the modern requirements of competitiveness, quality, and exibility. Therefore, new meth- ods are required. One of these methods is the cold spray technology. However, studies do not give clear indications on how the cold spray technology could be used to fabricate porous structures. Consequently, this thesis uses various methods such as the control of cold spray parameters, powder mixtures, and the integration of the cold spray with alloy-de-alloy process to investigate the capability of cold spray technology to manufacture porous structures. The results of this investigation proved that the cold spray technology can be used to fabricate porous structures with varied amount of porosity for a number of applications. / MT 2018

Esta dissertação analisa o potencial de mercado do gás natural boliviano em trinta e sete municípios paulistas, localizados ao longo do gasoduto ainda em fase de projeto. A partir da análise dos últimos 15 anos da matriz energética, do Estado de São Paulo, é realizada uma extrapolação de tendências do crescimento da demanda de gás natural para os setores industrial, comercial, residencial, e de transportes, até o ano 2015. Contata-se que a oferta é menor que a demanda existente e que somente no setor industrial, o gás natural pode substituir diretamente 116 MW de energia elétrica, utilizada no aquecimento de processo. Este trabalho indica que a cogeração e a produção independente enquanto formas de geração descentralizada, utilizando gás natural e subprodutos da cana, é uma prática mais recomendável que a construção de uma unidade de termogeração centralizada e de grande escala. / This work analyses the potential Market for Bolivian natural gas at thirty seven municipalities of de São Paulo State. These municipalities are located on the neighborhood of the proposed pipeline route. Data of the last 15 years allowed the extrapolation natural gas demand trend until the year 2015, for the industrial, commercial, residential and transport sectors. It was concluded that supply is smaller than demand and that is possible to substitute natural gas for 116 MW of currently used electric power in heat processes. This work indicates that the cogeneration and decentralized independent power production, utilizing natural gas and sugar0cane by-products, is an option more attractive than the construction of a large centralized thermogeneration unit.

O desenvolvimento de uma indústria de gás natural no Brasil tem sido debatido com mais ênfase desde meados da década de 80, quando diversos estados, desejosos de diversificar sua matriz energética, provendo o mercado com um energético de inegável apelo ambiental, reuniram-se em Brasília, sob a égide da Comissão Nacional de Energia e iniciaram as primeiras projeções de demanda e de uso nal para o gás natural. Desde então, a indústria de gás no pais tem apresentado índices signicativos de crescimento, com a criação de novas empresas concessionárias de distribuição e o aumento do consumo, notadamente nos estados de São Paulo, Minas Gerais, Bahia e Rio de Janeiro. A perspectiva de importação de gás boliviano, com a assinatura, em 1992, de um primeiro protocolo de intenções entre a Petrobrás e a Yacimientos Petrolíferos Fiscales Bolivianos- YPFB, gerou um longo processo de negociações entre a estatal brasileira e as distribuidoras de gás canalizado de São Paulo (Comgás), Minas Gerais (Gasmig), Rio de Janeiro (CEG), Mato Grosso do Sul (Enersul), Paraná (Compagás), Santa Catarina (SC Gás) e Rio Grande do Sul (SuIgás), visando a assinatura de contratos de suprimento com prazo de 20 anos. O principal impasse à concretização desses contratos diz respeito à definição do preço máximo do gás no ponto de entrega às concessionárias (\"city gate\")\', para o qual, acrescendo-se a margem de distribuição, ter-se-ia a adesão do consumidor. A grande dificuldade consiste em ajustar o preço imposto pela Petrobrás, o qual fugindo à lógica econômica, será equalizado em todos os pontos de entrega, de Corumbá e Porto Alegre, com o preço considerado competitivo para o mercado industrial, hoje abastecido basicamente com óleo combustível de alto teor de enxofre. O trabalho desenvolvido nesta dissertação tem por objetivo determinar o preço competitivo do gás natural em São Paulo, tanto no consumidor industrial como no city gate e quais os volumes contratuais que poderão vir a ser aceitos pela Comgás, atual concessionária estadual de distribuição de gás canalizado, caso haja flutuações nos preços ora ofertados pela Petrobrás. Considerando ainda o grande número de estudos de mercado desenvolvidos no Estado, desde meados da década de 80, neste trabalho também será apresentado uma análise e um resumo dos principais resultados desses estudos, buscando disponibilizar, para todos aqueles interessados no estudo. / The development of the natural gas industry in Brazil has been emphatically discussed since the mid-Eighties, when representatives of several Brazilian States willing to diversify their energy share and supply the market with a clean source of energy, met in Brasil\'s capital, sponsored by the former National Energy Commission and prepared the first long term gas consumption forecasts. Since then, the Brazilian gas sector has shown an enhanced growth, helped by the establishment of new local distribution concessionnaires and also by an increase in gas consumption in the states of São Paulo, Minas Gerais, Bahia and Rio de Janeiro. After the signature of a rst memorandum of understanding between Petrobrás and Yacimientos Fiscales Bolivianos - YPFB in 1992, the perspective of importing gas from Bolivia produced a long negotiation process involving the Brazilian oil company and the seven state concessionaires: Comgas(SP), CEG(R.J), Gasmig(MG), Compagás{PR), Enersul(MS), SC Gás(SC) and Sulgás (RS); the goal was to sign a 20 years gas supply agreement. The main constraint refer to the maximum affordable city gate price for which the gas will remain competitive after adding the distribution margin. It has been very difcult to match the city gate price imposed by Petrobrás, that has not been settled according to economical criteria and shall be equalized in all city gates - from the close to the border Corumbá up to the far Porto Alegre - with a consumer\'s gate price which can be considered competitive to the high sulphur content fuel oil consumed in most factories in the Southern and Southeastern regions. This dissertation aims at estimating the competitive price to natural in the state of São Paulo, both at city gate and consumer\'s gate as well as the economical demand to be contracted by Comgás, the current São Paulo gas distribution concessionaire, according to a set of prices variation. Taking into account the wide quantity of market studies developed in São Paulo for more than 10 years, and the variety of data presented, this dissertation will also present an abstract of their most important results in such a way to make available for those interested in the gas sector in São Paulo a piece of history of this fascinating industry, in which the author has being participating for the last 18 years. It should also be emphasized that one has looked for making the estimates and preparing the simulations in a very impartial manner. Nevertheless one shall take into account that this work carries a viewpoint of the gas distribution sector and also of the market; sometimes it may show some vehement statements about the pace of gas development in the country and also about the often.

A importação de gás natural da Bolívia possibilitará considerável aumento de consumo deste combustível na Região Metropolitana de São Paulo (RMSP). Estudo de mercado recente concluiu pela viabilidade econômica de uma demanda industrial na região acima de 6 milhões de m\'/dia no ano 2000, quase o dobro do consumo atual. Neste trabalho procuramos avaliar, do ponto de visita da demanda , o impacto sobre o meio ambiente resultante desta mudança de combustível e, também, uma investigação sobre eventual mudança da eficiência energética do setor industrial convertido ao gás natural. Grande parte deste gás natural será consumido na substituição de óleo combustível (50%), na ampliação de sua utilização atual (40%) e no deslocamento da eletricidade (7,3%) e da biomassa (2,7%). Com os dados disponíveis sobre as emissões na RMSP , considerando os deslocamento dos outros combustíveis e o aumento de consumo de gás natural , adotando-se os coeficientes de emissão reconhecidos, efetuamos um balanço das emissões resultantes desta mudança. Para a avaliação da eficiência energética fazemos uma investigação direta das mudanças de consumo junto às indústrias já convertidas ao gás natural. O balanço realizado indica uma grande redução das emissões industriais dos óxidos de enxofre (94%) e uma redução apreciável da geração de gás carbônico nas indústrias convertidas ao gás natural ( 13,4%). Apresenta uma modesta redução de material particulado (7,6%) e de monóxido de carbono (4%) e uma considerável redução na geração de óxidos de nitrogênio (13,7%). A nossa investigação indica a possibilidade de redução de consumo energético nos setores pesquisados e nítidos ganhos na operação e manutenção das instalações industriais convertidas ao gás natural. / With the Brazilian importation of natural gas from Bolívia, it will be feasible a considerable increase in the consumption of this fuel in the Great São Paulo Area. Recent evaluations concluded by the feasibility of the industrial demand of natural gas in this area, higger than 6 million m3/day on year 2000 , more than two times the current consumption. In this work we carried out an evaluation , from the demand point of view, of the environmental impact due to fuel substitution and natural gas market increase. Also the investigation related to possible changes in energy efficiency of industrial sectors converted to natural gas users is developped here. The largest share of this natural gas will be utilised in the substituition of fuel oil (50%), increase on natural gas utilisation (40%), as well as replacement of eletricity (7,3%) and biomass (2,7%). Based in the available air quality data for this urban area, in the replacement of other fuels, and the acceptable emissions coefficients, we present a balance of the final situation. For the evaluation of energy efficiency , a direct investigation about the change in consumption at industries already converted to natural gas was performed. The study indicates a scenario where considerable reduction on industrial emissions of sulfur oxides (94%), a significant reduction of carbonic dioxide (13,4%), a modest reduction on particulates (7,6%) and carbon monoxide (4%), and a considerable reduction too on nitrogen oxides (13,7%). Our investigation indicated the possibility of reduction on the energy comsumption , of the industrial sectors investigated and clear earnings on operation and maintenance of industrial instalations converted to natural gas.

No description available.

by Kwan Yuk-choi James, Ng Yuk-kau Sam. / Bibliography: leaves 111-112 / Thesis (M.B.A.)--Chinese University of Hong Kong, 1982

by Cheung Yiu-ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1990. / Includes bibliographies. / ACKNOWLEDGMENT / ABSTRACT / Chapter CHAPTER 1 --- GENERAL INTRODUCTION --- p.1 / Chapter 1.1 --- REVIEW OF GAS-LIQUID CHROMATOGRAPHY --- p.1 / Chapter 1.2 --- APPLICATION OF GAS-LIQUID CHROMATOGRAPHY IN DRUG ANALYSIS --- p.8 / Chapter 1.3 --- AIMS OF THE PRESENT WORK --- p.9 / REFERENCES --- p.11 / Chapter CHAPTER 2 --- GAS-LIQUID CHROMATOGRAPHIC DETERMINATION OF ACTIVE INGREDIENTS IN COUGH-COLD SYRUP FORMULATIONS --- p.12 / Chapter 2.1 --- INTRODUCTION --- p.12 / Chapter 2.2 --- EXPERIMENTAL --- p.16 / Chapter 2.3 --- RESULTS AND DISCUSSION --- p.22 / Chapter 2.4 --- CONCLUSION --- p.73 / REFERENCES --- p.74 / Chapter CHAPTER 3 --- "GAS-LIQUID CHROMATOGRAPHIC DETERMINATION OF ATROPINE SULFATE/HYOSCYAMINE SULFATE, HOMATROPINE HYDROBROMIDE AND HYOSCINE HYDROBROMIDE IN PHARMACEUTICAL PREPARATIONS" --- p.75 / Chapter 3.1 --- INTRODUCTION --- p.75 / Chapter 3.2 --- EXPERIMENTAL --- p.79 / Chapter 3.3 --- RESULTS AND DISCUSSION --- p.85 / Chapter 3.4 --- CONCLUSION --- p.126 / REFERENCES --- p.127 / APPENDIX --- p.128 / Chapter A.1 --- INTRODUCTION --- p.128 / Chapter A.2 --- EXPERIMENTAL --- p.129 / Chapter A.3 --- RESULTS AND DISCUSSION --- p.132 / Chapter A.4 --- CONCLUSION --- p.147 / REFERENCE --- p.147 / LEGENDS FOR FIGURES / LEGENDS FOR TABLES

The purpose of this consultation report was to examine the opportunities available to TgP for achieving its overarching strategic objectives, particularly its aims of bolstering corporate reputation and creating shared value for the communities which are impacted by the firm’s operations. The scope of this examination was confined primarily to opportunities in the Huamanga province, due to the fact that there is pre-existing infrastructure there which is currently underutilized. To identify the best opportunity available in the area, analyses are conducted on the external, industry, and internal levels for TgP. From this, the opportunity for TgP to transport natural gas to the Huamanga region was identified. To determine the best method by which to execute on this opportunity, the existing literature was reviewed and complemented with quantitative and qualitative analysis. The chosen method is to transport natural gas to Huamanga via a polyethylene pipeline approximately 6.3 Km long and 8 inches in diameter. While the implications and projected revenues of this proposal are rather minimal in the scale of TgP’s overall operations, the project is likely to constitute a community outreach victory regarding Huamanga. In short, this is a triumph for all parties involved, as the community benefits from access to natural gas, while TgP benefits from making use of idle infrastructure and capabilities, and the government benefits from the furthering of their Massification initiative. The results and specific recommendations of this report are not generalizable, as the solution is purpose-built for the area. However, this may also serve as a pilot proposal for similar socially-driven ventures in other regional communities if executed successfully. / El propósito de este informe de consultoría fue el de examinar las oportunidades disponibles para que TgP logre sus objetivos estratégicos, particularmente sus objetivos de reforzar la reputación corporativa y crear valor compartido para las comunidades que colindan con las operaciones de la empresa. El alcance de este estudio se limitó principalmente a las oportunidades en la provincia de Huamanga, debido a la presencia una infraestructura preexistente que en la actualidad esta no es utilizada. Para identificar la mejor oportunidad disponible, los análisis se realizaron a nivel externo, industrial e interno de TgP. A partir de esto, se identificó la oportunidad para TgP de transportar gas natural a la región de Huamanga. Para determinar el mejor método disponible para la ejecución de dicha oportunidad, la literatura existente fue revisada y complementada con los análisis cuantitativo y cualitativo. El método elegido es el de transportar gas natural a Huamanga a través de una tubería de polietileno de aproximadamente 6.3 km de largo y 8 pulgadas de diámetro. Si bien las implicaciones y los ingresos proyectados de esta propuesta son bastante mínimos en la escala de las operaciones generales de TgP, es probable que el proyecto constituya una victoria de alcance comunitario con respecto a Huamanga. En resumen, se trata de un triunfo para todas las partes involucradas, ya que la comunidad se beneficia del acceso al gas natural, mientras que TgP se beneficia de la infraestructura inutilizada y el gobierno se beneficia de la promoción de su iniciativa de Masificación de energía. Los resultados y las recomendaciones específicas de este informe no son generalizables, ya que la solución está especialmente diseñada para la región. Sin embargo, esto también puede servir como una propuesta piloto para iniciativas sociales similares impulsadas en otras comunidades regionales si se ejecuta con éxito. / Tesis

The composition of volcanic gas plumes depends largely on the chemistry of the degassing magma, the depth of volatile exsolution, and the level of volcanic activity. The ratios between the most common volcanic gases: C02, H2O, SO2, HCl and HF, as measured at the surface, can be used to provide information on the evolution of the magma body. My research on volcanic gases has centred on the use of open-path Fourier transform IR spectroscopy (Op_FTTR) and correlation spectroscopy (COSPEC). I have also used data collected using other direct and remote-sensing techniques. Remote-sensing techniques rely on the characteristic IR or UV absorbances of natural and/or artificial radiation by different gases. The longer range of these techniques enables the analysis of gases in inaccessible plumes; thus reducing the need for operators to enter hazardous areas. As the instruments do not interact with the analysed gases there is no contamination, condensation or secondary reactions. However, the instruments tend to be heavy, expensive, and complex. Environmental factors can complicate analyses; clouds can dissolve and remove analyte rapidly, and variations in wind speed can result in gas fluxes having high errors. It is also much more difficult to analyse specific gas sources remotely as mixing of gases from different sources can occur. Direct-sampling techniques rely on gases being trapped, dissolved or adsorbed before being analysed by traditional methods, e. g. wet-chemistry, colourimetry, and gas chromatography. The capture of gases is best achieved as close to the source as possible, thus increasing the risk to the operator, and may only be possible during periods of low activity. The physical interaction of gases with instrument and collection vessels can lead to contamination and initiation of secondary reactions. Direct-sampling techniques are labour intensive and thus are capable of only generating a relatively small amount of data compared to the more automated remote-sensing techniques. The suitability of an individual technique therefore depends greatly on: the type of gas to be measured; the location of vent or fumamle; the level of volcanic activity; and the environment in which data are collected. I used OP-FrIR on La Fossa di Vulcano to measure the S02: HCI mass ratios of gases emitted from the rim and central crater fumaroles, -4.3 - 6.1 and 0.9 - 2.6 respectively. I attributed the higher crater rim gas ratios to the interaction of the gases with shallow hydrothermal reservoirs, causing scrubbing of the more soluble HCl- At Mt. Etna, my OP-FTIR analysis of gases emitted from the central craters showed that, in 1994, S02: HC1 mass ratios were -4.9 - 5.8. These values lie between those reported for eruptive degassing, >10, and background degassing, < I, and probably relate to refilling of the magma system prior to the 1997 eruption. A comparative study of lava effusion rates and COSPEC-derived SO2 fluxes for the 1991 - 1993 Etna eruption showed that variations were generally synchronous; small scale differences relating to the drainage of degassed magma from beneath the summit craters into the eruptive fissure. I also conducted OP-FT'IR and COSPEC analyses on Montserrat in June 1996 to show the gas plume to be relatively S02 poor, with S02: HC1 mass ratios of < 0.5. The OP-FTIR technique enabled the first remote measurements of SiF4 in volcanic plumes to be made. I have also used HF-SiF4 ratios to estimate gas equilibrium temperatures at La Fossa and Mt. Etna to be --200°C and -250 - 290°C respectively. I have also investigated the structural evolution of the Masaya Volcanic Complex. The visible complex has formed over -1000 years; with average rates of effusion of -0.2 x 106 m3/y, much lower than those required to provide the estimated volume of caldera infill, -2 x 106 m3/y. Historic activity has centred on the twin massifs of Volcän Masaya and Volcän Santiago and is dominated by pit-crater collapses. I propose that the degassing episodes, which occur with no increase in eruptive activity, are related to the convective overturn of magma beneath the craters.