The Biomass Integrated Gasification Application Systems (BIGAS) consortium is a research group whose focus is on developing modern biomass gasification technology for New Zealand's wood industry. This thesis is undertaken under objective four of the BIGAS consortium, whose goal is to develop modelling tools for aiding in the design of pilot-scale gasification plant and for assessing the economic feasibility of gasification energy plant. This thesis presents a chemical equilibrium-based gasification model and an economic feasibility assessment of gasification energy plant. Chemical equilibrium is proven to accurately predict product gas composition for large scale, greater than one megawatt thermal, updraft gasification. However, chemical equilibrium does not perform as well for small scale, 100 to 150 kilowatt thermal, Fast Internally Circulating Fluidised Bed (FICFB) gasification. Chemical equilibrium provides a number of insights on how altering gasification parameters will affect the composition of the product gas and will provide a useful tool in the design of pilot-scale plant. The economic model gives a basis for judging the optimal process and the overall appeal of integrating biomass gasification-based heat and power plants into New Zealand's MDF industry. The model is what Gerrard (2000) defines as a 'study estimate' model which has a probable range of accuracy of ±20% to ±30%. The modelling results show that gasification-gas engine plants are economically appealing when sized to meet the internal electricity demands of an MDF plant. However, biomass gasification combined cycle plants (BIGCC) and gasificationgas turbine plants are proven to be uneconomic in the New Zealand context.

Thesis (Ph.D. (Economics))--North-West University, Potchefstroom Campus, 2008.

South Africa's North West Province is dependent on gold and platinum exports for its economic growth and employment. Whether this specialisation is optimal from an economic growth, employment creation and welfare point of view, or whether greater export diversification should be encouraged, can most appropriately be evaluated using a general equilibrium framework. Moreover, the answer of whether such specialisation or rather diversification is appropriate may differ depending on the spatial level of analysis that is taken. For instance, export diversification or specialisation on a national level might differ from export diversification or specialisation on sub-national (e.g. provincial) level. A general equilibrium framework is most appropriate for investigating the potential differences between these levels as it takes into consideration a region's economic structure, and the economy-wide linkages between demand, supply, production structure and income distribution. In this light this thesis proposes a regional applied general equilibrium (RAGE) model for the North West Province to address these issues. The question asked is, how can a RAGE model be formulated and implemented for the North West Province of South Africa in order to study the differential impacts of greater export specialisation versus greater export diversification? In answering this question this thesis provides policy makers at regional/provincial level with access to a potentially useful modelling tool, to analyse regional economic issues; it contributes to better understanding the spatial concentration and spatial dynamics of economic activity in the North West Province; and contributes toward the practical policy debate in South Africa. This thesis reviews the literature on export diversification and specialisation, by investigating the extent of export diversification and specialisation in the North West Province over the period 1995-2006 and its relationship to GDP per capita, and using a RAGE model to investigate the economy-wide impacts of greater export diversification versus greater export speciaRsation. These results are contrasted by investigating the economy-wide impacts of greater export diversification versus greater export specialisation on the national level, using a country-wide applied general equilibrium (AGE) model for South Africa. It is found that greater export diversification results in a more substantial increase in exports (of between 0.95 and 1.73 per cent) than in the case of greater export specialisation. In fact it was found that if the North West Province were to specialise in mining exports, such exports would need to grow or increase from the base year by approximately 78 per cent (with no increase in the export demand for other sectors) to result in the same level of growth of total export volumes as is found under export diversification. Avenues for further research are identified. These are a need for more research on elasticities and parameters at regional level, an expansion of the transport services sector in the model, incorporating Tourism Satellite Accounts, BEE and SMME aspects into the model, etc. In conclusion, the thesis implemented the first provincial regional applied general equilibrium model for South Africa, and illustrated that it can make an important contribution to the policy debate on a provincial level in South Africa. The construction of Social Accounting Matrices (SAMs) for all of South Africa's provinces, and the maintenance of these provincial databases could therefore make further contributions to the quantitative assessment of policy options facing government on both the national and provincial level. / Thesis (Ph.D. (Economics))--North-West University, Potchefstroom Campus, 2008.

South Africa's North West Province is dependent on gold and platinum exports for its economic growth and employment. Whether this specialisation is optimal from an economic growth, employment creation and welfare point of view, or whether greater export diversification should be encouraged, can most appropriately be evaluated using a general equilibrium framework. Moreover, the answer of whether such specialisation or rather diversification is appropriate may differ depending on the spatial level of analysis that is taken. For instance, export diversification or specialisation on a national level might differ from export diversification or specialisation on sub-national (e.g. provincial) level. A general equilibrium framework is most appropriate for investigating the potential differences between these levels as it takes into consideration a region's economic structure, and the economy-wide linkages between demand, supply, production structure and income distribution. In this light this thesis proposes a regional applied general equilibrium (RAGE) model for the North West Province to address these issues. The question asked is, how can a RAGE model be formulated and implemented for the North West Province of South Africa in order to study the differential impacts of greater export specialisation versus greater export diversification? In answering this question this thesis provides policy makers at regional/provincial level with access to a potentially useful modelling tool, to analyse regional economic issues; it contributes to better understanding the spatial concentration and spatial dynamics of economic activity in the North West Province; and contributes toward the practical policy debate in South Africa. This thesis reviews the literature on export diversification and specialisation, by investigating the extent of export diversification and specialisation in the North West Province over the period 1995-2006 and its relationship to GDP per capita, and using a RAGE model to investigate the economy-wide impacts of greater export diversification versus greater export speciaRsation. These results are contrasted by investigating the economy-wide impacts of greater export diversification versus greater export specialisation on the national level, using a country-wide applied general equilibrium (AGE) model for South Africa. It is found that greater export diversification results in a more substantial increase in exports (of between 0.95 and 1.73 per cent) than in the case of greater export specialisation. In fact it was found that if the North West Province were to specialise in mining exports, such exports would need to grow or increase from the base year by approximately 78 per cent (with no increase in the export demand for other sectors) to result in the same level of growth of total export volumes as is found under export diversification. Avenues for further research are identified. These are a need for more research on elasticities and parameters at regional level, an expansion of the transport services sector in the model, incorporating Tourism Satellite Accounts, BEE and SMME aspects into the model, etc. In conclusion, the thesis implemented the first provincial regional applied general equilibrium model for South Africa, and illustrated that it can make an important contribution to the policy debate on a provincial level in South Africa. The construction of Social Accounting Matrices (SAMs) for all of South Africa's provinces, and the maintenance of these provincial databases could therefore make further contributions to the quantitative assessment of policy options facing government on both the national and provincial level. / Thesis (Ph.D. (Economics))--North-West University, Potchefstroom Campus, 2008.

Speciation governs transport and toxicity of trace metals and is important to monitor in natural waters. Geochemical models that predict speciation are valuable tools for monitoring. They can be used for risk assessments and future scenarios such as termination of liming. However, there are often large uncertainties concerning the speciation of iron and aluminium in the models, due to the complicated chemistry of these metals. Both are important in governing the speciation of other metals, due to (i) their capacity to form minerals onto which metals can adsorb and (ii) their ability to compete for binding sites to natural organic matter (NOM). Aluminium is also potentially toxic and is therefore closely monitored in acidified freshwaters. In this study different phases of iron in Swedish lakes were characterised. This required a good method for preconcentrating the iron colloids. A new method was developed in this thesis that uses an anion-exchange column to isolate the iron colloids prior to characterisation with extended X-ray absorption fine structure (EXAFS) spectroscopy. Iron was present as ferrihydrite in particles but was also strongly monomerically complexed to NOM in two Swedish lakes. Based on the results an internally consistent process-based geochemical equilibrium model was presented for Swedish freshwaters. The model was validated for pH (n = 9 400) and inorganic monomeric aluminium (Ali) (n = 3 400). The model could simulate pH and Ali simultaneously, and be used for scenario modelling. In this thesis, modelling scenarios for decreases and complete termination of liming are presented for the 3 000 limed Swedish lakes. The results suggest that liming can be terminated in 30 % of the Swedish lakes and decreased in many other lakes. / <p>QC 20120919</p>

O objeto de estudo desta Tese é o impacto da formação da Área de Livre Comércio das América (Alca) sobre a economia brasileira. A economia brasileira não é homogênea internamente, possuindo contrastes importantes entre setores e regiões. A Alca, por seu lado, pode ser considerada um bloco de países com interesses distintos e marcada por importantes assimetrias. Devem ser esperados, dessa forma, impactos espaciais e setoriais diferenciados na economia brasileira como fruto das diferentes alternativas de acordo que surjam das negociações na Alca. O estudo dessas questões requer uma metodologia adequada, que considera de maneira sistemática as relações inter-regionais e intersetoriais, assim como a inserção internacional das economias locais. Modelos inter-regionais de equilíbrio geral computável são ferramentas importantes nessa área, e exemplos para a economia brasileira são encontrados na literatura. SPARTA (São Paulo Applied Regional Trade Analysis) é o modelo inter-regional de equilíbrio geral computável implementado nesta Tese. Uma de suas inovações está no tratamento detalhado dos fluxos externos, especificando mercados de origem e destino para as importações e exportações regionais, o que possibilita simular os impactos da liberalização tarifária no âmbito da Alca. Os resultados obtidos permitem projetar um efeito positivo da liberalização tarifária na Alca para o crescimento do PIB e geração de superávit comercial, no longo prazo. Regionalmente, entretanto, os impactos atuam no sentido da concentração relativa da produção e investimento na economia paulista. Além disso, uma importante diferenciação setorial dos impactos da liberalização na Alca pode ser identificada. Dentro dessa perspectiva, são discutidos aspectos relacionados à necessidade e adequação de políticas públicas. / The process of trade liberalization in Brazil has been extended in recent years to broader regional trade agreements, motivated by both economic and political objectives. The country has been pursuing different strategies of regional integration in an attempt to strengthen strategic impulses for economic development. One of the alternatives for the development of an economic trading block is the Free Trade Area of the Americas (FTAA), a process initiated in the 1994 Summit of the Americas to integrate the economies of the Western Hemisphere into a single free trade agreement. In this dissertation an interregional CGE model is used to analyze the short-run and long-run regional and sectoral effects of trade liberalization in a FTAA agreement. The model provides a description of the Brazilian inter-regional economic system, separated in two regions, São Paulo and Rest of Brazil. One of its innovations is a full specification of foreign trade in both regions, capturing the complete structure of trade flows linking the two Brazilian regions and FTAA markets. In this way, adequate tariff liberalization simulations can be implemented. The model simulations provide results in macro, regional and sectoral levels. A positive effect of FTAA liberalization on Brazilian GDP growth and trade balance can be expected. However, the results suggest that the interplay of market forces in the Brazilian economy favors the more developed state of the country (São Paulo). Additionally, sectoral liberalization under FTAA can produce heterogeneous regional impacts. These figures provide the framework to discuss adequate regional economic policies.

O objeto de estudo desta Tese é o impacto da formação da Área de Livre Comércio das América (Alca) sobre a economia brasileira. A economia brasileira não é homogênea internamente, possuindo contrastes importantes entre setores e regiões. A Alca, por seu lado, pode ser considerada um bloco de países com interesses distintos e marcada por importantes assimetrias. Devem ser esperados, dessa forma, impactos espaciais e setoriais diferenciados na economia brasileira como fruto das diferentes alternativas de acordo que surjam das negociações na Alca. O estudo dessas questões requer uma metodologia adequada, que considera de maneira sistemática as relações inter-regionais e intersetoriais, assim como a inserção internacional das economias locais. Modelos inter-regionais de equilíbrio geral computável são ferramentas importantes nessa área, e exemplos para a economia brasileira são encontrados na literatura. SPARTA (São Paulo Applied Regional Trade Analysis) é o modelo inter-regional de equilíbrio geral computável implementado nesta Tese. Uma de suas inovações está no tratamento detalhado dos fluxos externos, especificando mercados de origem e destino para as importações e exportações regionais, o que possibilita simular os impactos da liberalização tarifária no âmbito da Alca. Os resultados obtidos permitem projetar um efeito positivo da liberalização tarifária na Alca para o crescimento do PIB e geração de superávit comercial, no longo prazo. Regionalmente, entretanto, os impactos atuam no sentido da concentração relativa da produção e investimento na economia paulista. Além disso, uma importante diferenciação setorial dos impactos da liberalização na Alca pode ser identificada. Dentro dessa perspectiva, são discutidos aspectos relacionados à necessidade e adequação de políticas públicas. / The process of trade liberalization in Brazil has been extended in recent years to broader regional trade agreements, motivated by both economic and political objectives. The country has been pursuing different strategies of regional integration in an attempt to strengthen strategic impulses for economic development. One of the alternatives for the development of an economic trading block is the Free Trade Area of the Americas (FTAA), a process initiated in the 1994 Summit of the Americas to integrate the economies of the Western Hemisphere into a single free trade agreement. In this dissertation an interregional CGE model is used to analyze the short-run and long-run regional and sectoral effects of trade liberalization in a FTAA agreement. The model provides a description of the Brazilian inter-regional economic system, separated in two regions, São Paulo and Rest of Brazil. One of its innovations is a full specification of foreign trade in both regions, capturing the complete structure of trade flows linking the two Brazilian regions and FTAA markets. In this way, adequate tariff liberalization simulations can be implemented. The model simulations provide results in macro, regional and sectoral levels. A positive effect of FTAA liberalization on Brazilian GDP growth and trade balance can be expected. However, the results suggest that the interplay of market forces in the Brazilian economy favors the more developed state of the country (São Paulo). Additionally, sectoral liberalization under FTAA can produce heterogeneous regional impacts. These figures provide the framework to discuss adequate regional economic policies.

The growing bacterial resistance against antibiotics creates a limitation for using traditional antibiotics and requests development of new approaches for treatment of bacterial infections. Among the bacterial infections that are most difficult to treat, biofilm-associated infections are one of the most hazardous. Consequently, the prevention of biofilm formation is a very important issue. One of the techniques that are widely investigated nowadays for this purpose is surface modification by polymer brushes that allows generating antifouling antibacterial surfaces. Previously, it was reported that salicylidene acylhydrazides (hydrazones) are good candidates as antivirulence drugs targeting the type three secretion system (T3SS). This secretion system is used by several Gramnegative pathogens, including Pseudomonas aeruginosa, to deliver toxins into a host cell. Furthermore, the chemical structure of these substances allows formation of complexes with metal ions, such as Fe3+ and Ga3+. The antibacterial activity of Ga3+ is well known and attributed to its similarity to the Fe3+ ion. It has also been shown that Ga3+ ions are able to suppress biofilm formation and growth in bacteria. In this thesis the chemistry of antibacterial and antivirulence Ga3+-Hydrazone complexes in solution was studied. First, to get insights in the solution chemistry, the protonation and the stability constants as well as the speciation of the Ga3+-Hydrazone complexes were determined. Additionally, a procedure for anchoring one of the hydrazone substances to antifouling polymer brushes was optimized, and the resulting surfaces were characterized. Results showed that the complexation with Ga3+ ions stabilizes the ligand and increases its solubility. Ga3+ ion binds to the hydrazone molecule forming a strong chelate that should be stable at physiological conditions. The different biological assays, such as Ga3+ uptake, antivirulence and antibiofilm effects, indicated very complex interaction of these complexes with the bacterial cell. Negatively charged and zwitterionic surfaces strongly reduced protein adsorption as well as biofilm formation. Therefore, the antifouling zwitterionic poly-[2-(methacryloyloxy)ethyl]dimethyl-3- sulfopropyl)-ammonium hydroxide (pMEDSAH) brushes were post-modified and successfully functionalized with bioactive substances via a block-copolymerization strategy. However, in order to maintain the availability of the bioactive substance after functionalization, the hydrophobic polyglycidylmethacrylate (pGMA) top block is probably better to functionalize with a lipophilic molecules to reduce diblock copolymer brush rearrangement.

No description available.

Chapter 1: A Population Aging Analysis for Canada Using the National Transfer Accounts Approach: This analysis develops a new data set for Canada using an accounting methodology called National Transfer Accounts (NTA). NTA permits building an accounting system that introduces age into national accounts. NTA is consistent with the conventional national accounts and allows the estimation of lifecycle patterns for labour income and consumption from private and public sources. It also allows the calculation of per capita and aggregate lifecycle deficits (LCD) or surpluses (LCS) in an economy. In this chapter we calculate Canada’s per capita and aggregate LCD for 2006. Using demographic projections for the next five decades, we present the aggregate LCD in Canada for the period 2006 to 2056 assuming a constant per capital LCD during this time horizon. The projection results show that labour income needs to increase rapidly or consumption needs to be cut significantly to compensate for the pressure on the aggregate lifecycle deficit as a result of population aging. Chapter 2: An Overlapping Generations Computable General Equilibrium (OLG-CGE) Model with Age-dependent Rates of Time Preference: This analysis develops a methodology to introduce an age-dependent rate of time preference to calibrate an OLG-CGE model with per capita age profile consumption path derived from the NTA framework of Chapter 1. The results show that the economic impact from an aging population will be significant. The living standard will decline by 15% from the present to 2050 and decline by 20% by the year 2105. To reduce such a decline, the Canadian government may introduce policies that could encourage labour force participation. We analyze the impact of: a) an increase in the general labour force participation rate for age 20 to 64; b) an increase in the labour force participation rate for workers aged 50 to 64; c) late retirement. Our results suggest that maintaining the current standard of living will be extremely difficult after 2026. Nevertheless, this would help reduce the economic pressure from population aging. Chapter 3: 9/11 Security Measures and North American Security Perimeter: A Computable General Equilibrium Analysis: The objective of this analysis is to assess the impact of the North American Security Perimeter (NASP) on both the Canadian and the U.S. economies. The NASP is a change in Canada-U.S. security paradigm that would allow the liberalization of the post 9/11 security measures at the Canada-U.S. border. This study applies a multi-sector and multi-region general equilibrium model together with econometric analysis. After simulating the NASP, Canada’s capital market was found to become more attractive. Under the NASP, the welfare of Canada is estimated to increase by $19 billion or 1.8% of GDP, and that of the U.S. is estimated to increase by $32 billion or 0.3% of GDP.