Philosophiae Doctor - PhD / Light olefins are some of the main raw materials for the petrochemical industry. With the rise in oil prices and increasing demand for olefins, there is an increasing interest in finding cheaper alternatives for processes in the petrochemical industry (PETROSA 2017). Research into the dehydrogenation of light alkanes has received significant attention. This dehydrogenation process represents a route to obtain olefins from inexpensive hydrocarbon feedstocks. The use of inexpensive hydrocarbons as a feedstock in the petrochemical industry could reduce the dependence on oil. Commercially used catalysts based on chromium or platinum have major disadvantages, including the harmful effects of chromium and the high cost of platinum, which limit their application to a certain extent. Therefore, research into developing efficient dehydrogenation systems using environmentally friendly and inexpensive metals have become highly desirable. Sulfide-containing metal catalysts have gained significant research interest for use in the dehydrogenation process and display interesting catalytic activity. / 2024

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This master thesis aims to examine the relationship between energy consumption and economic growth and between energy consumption and greenhouse emissions for the EU countries, using a panel time series data from 1996 to 2012 within a multivariate framework for 26 EU countries. The energies are composed from oil consumption, natural gas consumptions, and renewable energies including the biomass as a distinct part. To do that, Unit Root Tests, cointegration test, Pairwise Granger causality tests, and Error Correction Model are employed to find out the type of the causal relationship. The main results to denote are that, there is in the short run, a positive unidirectional causal relationship running from oil consumption to economic growth. We can as well denote a positive bidirectional causal relationship between renewable energies and economic growth and between greenhouse emissions and economic growth. However, there is an unexpected negative bidirectional causal relationship between biomass consumption and gas consumption. From the greenhouse emissions perspective, we can see in the short run, a negative bidirectional causal relationship between greenhouse emissions and renewable energies, and a positive unidirectional causal relationship running from both oil consumption and biomass consumption...

It is well established that replacing dietary saturated fatty acids with unsaturated fatty acids reduces cardiovascular disease (CVD) risk. Although epidemiological and clinical evidence indicate health benefits of consuming various fatty acid classes including n-9, n-6, and short- and longer-chain n-3 fatty acids, current dietary recommendations fall short of providing the optimal amounts of these fatty acids in daily diets. In addition, significant knowledge gaps remain in our understanding of the effects of, and mechanisms underpinning the action of, the various fatty acid classes on risk factors for CVD. The objective of this research was to contribute to the evaluation of health benefits of using different dietary oils, and determine how these benefits may play a role in improving public health and decreasing CVD risk. Additionally, this research examined effects of diet-gene interactions, endogenous fatty acid ethanolamides (FAEs) on body fat mass distribution as well as changes in the composition of gut microbiota following consumption of dietary oil treatments. The Canola Oil Multicenter Intervention Trial (COMIT) was conducted as a 5-phase randomized, controlled, double-blind, cross-over clinical trial. Each 4-wk treatment period was separated by 4-wk washout intervals. A total of 130 volunteers with abdominal obesity consumed each of 5 identical weight-maintaining, fixed-composition diets with one of the following treatment oils (60 g/3000 kcal) in the form of beverages: 1) conventional canola oil (Canola; n-9 rich), 2) high–oleic acid canola oil with docosahexaenoic acid (CanolaDHA; n-9 and n-3 rich), 3) a blend of corn and safflower oil (25:75) (CornSaff; n-6 rich), 4) a blend of flax and safflower oils (60:40) (FlaxSaff; n-6 and short-chain n-3 rich), and 5) high–oleic acid canola oil (CanolaOleic; highest in n-9). At endpoints, plasma fatty acid levels reflected the differences in fatty acid composition of five dietary treatments. All diets lowered total cholesterol (TC) compared with baseline. TC was lowest after the FlaxSaff phase and highest after CanolaDHA. The CanolaDHA treatment improved HDL-C, triglycerides, and blood pressure thereby reducing Framingham risk scores compared with other oils varying in unsaturated fatty acid composition. Homozygotes minor allele carriers of rs174583 (TT) on FADS2 gene showed lower (P<0.01) plasma EPA and DPA levels across all diets, but no differences were observed in DHA concentrations after the CanolaDHA feeding. In addition, plasma FAE levels were positively associated with plasma fatty acid profiles. Minor allele A carriers of rs324420 of FAAH gene showed a higher (P<0.05) plasma FAE levels compared with major allele C carriers across all diets, and showed higher (P=0.0002) docosahexaenoylethanolamide levels in response to the CanolaDHA diet. Impacts of consuming 60 g of five dietary oil treatments on gut microbiota composition were relatively minor at the phylum level and mainly at the genus level, while BMI contributed to a significant shift at the phylum level. In conclusion, consumption of a novel DHA-enriched canola oil improved blood lipid profile and largely reduced CVD risk. Diet-gene interactions might help identify sub-populations who appear to benefit from increased consumption of DHA and oleic acid. The metabolic and physiological responses to dietary fatty acids may be influenced via circulating FAEs, while the altered microbiota profile by shifts in MUFA and/or PUFA may be associated with specific physiological effect. Personalized diets varying in unsaturated fatty acids composition based on specific lifestyles, environmental factors, psychosocial factors, and genetic make-ups will become the future “healthy eating” recommendations to prevent CVD risk. / May 2016

Particulate emissions from diesel engines have been a key issue for diesel engine developers in recent decades. Their work has succeeded in reducing the exhaust particles from the combustion of fuel, which has led to increasing interest in the contribution of particulates from lubrication oil. When discussing oil-related particulate emissions, hydrocarbon particles are customarily referred to. This thesis uses a broader definition, in which oil-related particulate emissions are modelled not only by the hydrocarbons, but also include the ash, carbons, and sulphate oil particulate emissions. The model developed in the project uses input data as oil consumption and oil ash content combined with tuning parameters, such as the oil ash transfer rate (ash emissions divided by oil consumption and oil ash content). Controlled engine tests have been performed to verify assumptions and fill knowledge gaps. The model can be applied to a variety of diesel engines, although the tuning factors might have to be reset. For example, introducing diesel particulate filters would dramatically reduce the oil ash emissions, since oil ash would accumulate in the filter. Oil consumption has played a central role in the present research. The modelling results indicate that special attention should be paid to oil consumption under running conditions with a low in-cylinder temperature, since the oil survival rate is high there. Under low-load and motoring conditions, hydrocarbons proved to be the main contributor to oil-related particulate emissions. At high engine load, oil ash emissions were the largest contributor to oil-related particulate emissions. / QC 20101103

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Environmental pollution is an important problem of our world. Governments are aware of this problem and emission regulations are continuously improved. One of the strictest regulations is about unburned and burned hydrocarbon emissions. In internal combustion engines the origin of the burned and unburned hydrocarbons is fuel and engine oil. As a result of the sanctions and the necessity of improved combustion performance of the engine, manufacturers work on manufacturing technology and engine tribology. With the improvement of these areas oil loss from internal combustion engine is reduced. Engine oil consumption mechanisms are specific research areas in the internal combustion engine development. Oil consumption occurs via to two main routes: &ldquo / Valve train&rdquo / and &ldquo / in cylinder components&rdquo / . In cylinder components have three sub mechanisms: evaporation, ring scraping and blowback. In this thesis, blowback oil loss mechanism is studied. 2D flow model of piston-cylinder mechanism is developed in Fluent. Land pressures and ring end gap flow data are taken from this model. An iterative computer program is developed to calculate backflow oil consumption. In this program, an empirical entrainment correlation compiled from literature is used. The calculated oil consumption values match with the range of the values in the literature.

Oil loss mechanisms in internal combustion engines have been subject to many researches. By the help of technological developments effects of several problems due to oil losses were examined and tried to be reduced. Environmental pollution and performance loss are important issues that oil consumption in internal combustion engines contribute. In this study the effects of individual parameters on the oil accumulation in 2nd land crevice of internal combustion engines, volume between top compression rings, were investigated. The study aimed to investigate the effects of oil film thickness and oil film temperature on the oil accumulation in the 2nd land which contributes to one of the mechanisms of oil consumption in internal combustion engines. Controlled experiments were performed on a modeled piston cylinder assembly. It was seen that oil accumulated in the 2nd land crevice by blow-by gases was affected by the film thickness of lubricating oil and the temperature of the lubricating oil. The amount of oil accumulated increased with increasing oil film thickness. The results also showed that below oil film thickness of 45 &amp / #956 / m / amount of oil accumulated increased with the increase of oil temperature.

Doctor Legum - LLD / African countries are faced with the daunting task of providing a comprehensive regulatory framework for their natural resources. This is at both the international and domestic level. The statement is particularly true for emerging African oil producing countries. Related to the above, it can be argued that production quotas, subsidies, and corruption continue to hinder the full liberalisation of the oil sector globally, and in Africa. Also, these three areas are the genesis of some of the prominent issues in the discussions of trade in energy goods. Although Africa is substantially endowed with natural resources like crude oil, it remains at the bottom of the development pecking order; accordingly, it has to get centrally involved in the debate on the regulation of international trade in oil to encourage development and to benefit from the resource. The World Trade Organisation (WTO) and the Organisation of Petroleum Exporting Countries (OPEC) are the most relevant organisations in the collective regulation of production quotas, oil consumption subsidies and the control of corruption in the oil sector. Both organisations, directly for the former, and indirectly for the latter, deal with trade between nations. OPEC‘s mandate is established in the OPEC Statute, while the mandate of the WTO is found in various multilateral and plurilateral agreements. However, the General Agreement on Tariffs and Trade (1994) (GATT), the Agreement on Subsidies and Countervailing Measures (SCM), and the Agreement on Government Procurement (GPA) are the most relevant. The Energy Charter Treaty (ECT) is only discussed where relevant. This is because the treaty is based on the WTO framework. Also, several provisions in the WTO agreements are not fully discussed in the ECT. OPEC which deals with regulation of oil production and to some extent oil prices in member countries has an effect on trade of the commodity. The role of the WTO however, is more direct as it regulates international trade of various vi goods and services. Thus this thesis investigates how the above legal frameworks regulate production quotas, subsidies, and corruption in the oil sector. The results of the foregoing investigation are then applied to African countries, such as, Nigeria, Angola (members of both the WTO and OPEC) and Ghana, an emerging African oil producing country, to assess the impact of these international rules on the countries‘ legal regimes. Ghana has recently developed its crude oil sector. The success of the nascent oil sector of this country may depend on the conception or improvement of a comprehensive legal framework, to regulate international trade in oil. It is apparent that without an effective legal framework to regulate international trade in oil, the discovery of oil in Ghana, may not make any long term positive impact on the current economic conditions. Ghana is a member of the WTO; however, it is yet to join OPEC, despite growing debate on its membership in the organisation.

Due to the vast fossil fuel wealth, the country of Saudi Arabia is experiencing a dramatic growth in both population and GDP. Therefore there is a growing demand for water and energy to meet these needs. All of the electricity that is generated is sourced from crude oil and natural gas. All natural gas production is used domestically and there are no net imports or exports. Due to many constrains on the natural gas supply, there is a slow shift in the generation mix going towards crude oil based power generation. This study assessed the viability of utility scale solar integration into the Saudi Arabian electric mix to potentially relieve some demand pressure for natural gas consumption as well as reduce green house gas emissions. Parabolic trough concentrated solar power technology was chosen as the primary technology for utility scale integration. A total of five scenarios were calculated. The scenarios include the following, base case, 5%, 10%, 15%, 20% solar integration in terms of installed capacity. Two sets of net present values were calculated. The net present values of each scenario were calculated. A second set of net present values was calculated with a projected increase in electricity prices. The natural gas and crude oil offset from the four solar integration scenarios were calculated using the base case forecasted natural gas and crude oil consumption from power generation. As expected, natural gas and crude oil consumption decreased when there was an increase in solar integration. The expected carbon dioxide offsets were calculated for each scenario. There was a decrease in carbon dioxide emission as solar integration was increased. Finally, all of these analyses were used as criteria for a decision analysis using the analytical hierarchy process. Depending on the decision maker’s importance on the determined criteria, solar integration in the Kingdom of Saudi Arabia is achievable. / text