Дисертації: "665:66.097.3"

1

Ситнік, Наталія Сергіївна. "Удосконалення технології переетерифікування жирів з використанням гліцератів лужних металів". Thesis, Український науково-дослідний інститут олій та жирів НААН, 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/23535.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.18.06 – технологія жирів, ефірних масел і парфумерно-косметичних продуктів. – Національний технічний університет "Харківський політехнічний інститут" Міністерства освіти і науки України, м. Харків, 2016. Дисертаційну роботу присвячено вирішенню конкретного науково-практичного завдання щодо розробки наукових засад технології переетерифікування жирів з використанням нових каталізаторів, які представляють собою гліцерати лужних металів. Визначено триацилгліцерольний склад початкових та переетерифікованих індивідуальних олій. Встановлено вплив переетерифікування з традиційним каталізатором на температуру плавлення олій. Обгрунтовано вибір тестового жиру для досліджень переетерифікування жирів. Доведено ефективність гліцерату калію та гліцерату натрію як каталізаторів переетерифікування жирів. Встановлено характер змін триацилгліцерольного складу тестового жиру у результаті переетерифікування у присутності гліцерату калію в порівнянні з промисловим каталізатором – метилатом натрію. Визначено термін зберігання гліцерату калію та виявлено можливість його регенерування після втрати каталітичної активності. Встановлено залежність каталітичної активності гліцерату калію від основних фізико-хімічних властивостей початкової сировини. Розроблено математичні моделі переетерифікування тестового жиру у присутності гліцерату калію в залежності від основних технологічних параметрів. Сформульовано рекомендації щодо вибору режимів та визначено раціональні умови переетерифікування. Доведено можливість застосування гліцерату калію у виробництві якісних переетерифікованих жирів із сумішей олій та жирів. Проведено економічні розрахунки собівартості гліцерату калію. Розроблено удосконалену технологію хімічного переетерифікування жирів з використанням гліцератів лужних металів. Розроблено проект технологічної інструкції на виробництво жирів переетерифікованих з використанням гліцератів лужних металів.
Thesis for a candidate degree of technical sciences by specialty 05.18.06 – fats, essential oils and perfume-cosmetic products technology. – National Technical University "Kharkov Polytechnic Institute" Ministry of Education and Science of Ukraine, Kharkov, 2016. The thesis is dedicated to specific scientific and practical task to develop the scientific foundations of fat interesterification technology using new catalysts that constitute alkali metals glycerates. Triacylglycerol composition of initial and interesterified samples of individual oils was defined. The influence of interesterification with traditional catalyst to the melting point of oils was installed. The choice of test fat for studies of fat interesterification was grounded. The efficiency of potassium glycerate and sodium glycerate as catalysts for interesterification of fats was proved. The character of triacylglycerol composition changes of test fat in the process of interesterification in the presence of potassium glycerate compared with industrial catalyst sodium methylate was installed. Shelf life of potassium glycerate was defined and the possibility of recovery after the loss of catalytic activity was revealed. The dependence of the catalytic activity of potassium glycerate on basic physical and chemical properties of the original material was installed. The mathematical model of the interesterification of test fat in the presence of potassium glycerate depending on the basic technological parameters was developed. Recommendations on the choice of modes were formulated and rational conditions of the interesterification were defined. The possibility of potassium glycerate use in the production of qualitive interesretified fats with mixtures of oils and fats was proved. Economic analysis of the cost potassium glycerate was conducted. The advanced chemical fat interesrerification technology using alkali metals glycerates was developed. The project of technical regulations for production of interesretified fats using alkali metals glycerates was developed.

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Kasim, Farizul Hafiz. "In situ transesterification of Jatropha curcas for biodiesel production." Thesis, University of Newcastle Upon Tyne, 2012. http://hdl.handle.net/10443/1788.

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Biodiesel is primarily produced by transesterification of edible oils. Increasing concern about using food supplies for fuel has generated interest in alternative raw materials. Furthermore, there are numerous steps between harvesting of oilseeds and final production of biodiesel that can be integrated, thereby simplifying the process and making it more suitable for distributed production. Hence, in this study, the production of biodiesel via in situ transesterification of non-edible Jatropha curcas seed has been investigated. The main aim was to investigate the parameters of the process, with a view to reducing the substantial excess of methanol required. A significant secondary aim was to investigate the possibility of utilising other compounds that come out from the process. “Design of experiments” was employed to study the parameters at lab-scale, with the matrix boundary being determined beforehand using one-at-a-time experiments. The reduction of methanol excess was attempted by use of two co-solvents, hexane and diethylmethane (DEM), and by replacing methanol with methyl acetate. It was found that in situ transesterification run using particle sizes below 0.71 mm, a 400:1 molar ratio of methanol to oil, 60 minutes, and a minimum of 300 rpm mixing intensity yielded the highest biodiesel yield of 83 wt %. NaOH concentration and reaction temperature were not found to be significant variables, and were set at 1.0 N and 30oC respectively. DEM was a more effective co-solvent than hexane. The addition of DEM to the process at 400:1 molar ratio experiment increased the yield from 83 to 92 wt %. When methyl acetate was used to replace methanol, the requirement of molar ratio of solvent:oil reduced significantly to 175:1 to achieved 86.8 wt% of biodiesel. The solid meal was shown to contain substantial amounts of protein, making it a valuable co-product stream. Previously J. curcas meal had had little value as animal feed due to its toxicity, but this may be reduced or removed by this process.

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Wye, Steven Matthew. "Polymorphic transitions in cocoa butter studied by time-resolved small-angle and wide-angle x-ray scattering using synchrotron radiation." Thesis, Keele University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590678.

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X-ray diffraction is a non-destructive technique which may be used to reveal information about the structure of materials, and is already a widely used tool in the study and determination of the polymorphic nature of cocoa butter and associated triacylglycerols which comprise cocoa butter. Simultaneous wide-angle x-ray scattering (WAXS) and small-angle scattering (SAXS) using synchrotron sources has been carried out on cocoa butter and cocoa butter containing selected additives. Conventional WAXS in a SAXS/\VAXS set up gives information on the cocoa butter atomic distances in the range of 3 - 8 angstroms (A), i.c. packing of cocoa butter chains, and is a familial' and powerful technique in enabling the identification of the polymorphic form of cocoa butter. Whereas SAXS provides information on length scales of 50 - 500 A, i.e. the layout of whole molecules in the form of layers. By using synchrotron sources and the associated high brilliance x-rays, it is possible to study the crystallisation in real-time. Whereas WAXS patterns can take a long time to develop, the associated SAXS patterns evolve before any peaks are observed in the WAXS and are concerned with the onset of crystallisation as well as changes in the pre-crystalline structure and pre-cursors prior to the onset of crystallisation which can determine the final characteristics and properties of the product. Similarly, during melting, the SAXS is the last to survive, in some cases long after the WAXS patterns have disappeared. By recording the SAXS patterns in real-time and using a suitably fast time resolution it is possible to observe the formation of the different polymorphic forms of cocoa butter. As well as transitions between polymorphs via intermediate phases which were observed, including the transition from form I to form III via an intermediate phase, and the formation of form V from the melt phase via an intermediate phase. SAXS studies also provided the ability to study cocoa butter systems containing additives such as sucrose, which itself produces a very strong pattern, making it impossible to identify cocoa butter using the conventional WAXS. It was observed that the addition of sucrose to cocoa butter at the onset resulted in a faster crystallisation rate and a shorter induction time. Other additives were used including silica particles of size 7 and 14 nm which provided a large surface area and also resulted in an increased crystallisation rate and a shorter induction time, seen to depend on surface area. The effect of stearic acid, which is one of the fatty acids present in the many triacylglyccrols of cocoa butter, was also observed in the following two situations: i) stearic acid present and already largely crystallised ii) stearic acid itself crystallising rapidly. It was found that cocoa butter crystallised at higher temperatures with stearic acid present, which promoted nucleation in particular.

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Bailey, Helen Katherine. "Novel uses of vegetable oil in asphalt mixtures." Thesis, University of East London, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.532999.

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Sustainable development has become a key ideal which must be translated into the real world, leaving scientists and engineers confronted with meeting demanding tasks of far-reaching environmental, economic and social objectives. Products must be developed that can be manufactured in environmentally acceptable ways with minimum consumption of energy and raw materials, whilst maintaining as favourable an ecological balance as possible [Metzger, 20011. Global drivers have led the construction industry to consider the use of recycled and waste materials to aid sustainability. A key area for development is in the use of alternative binders for asphalt. A primary target of this investigation was the development of technical knowhow for blending of bitumen and vegetable oil (both virgin and used) to produce a range of equivalent penetration grade binders referred to henceforth as Vegetex. This thesis begins by exploring and critically reviewing current applications of used vegetable oil in industry, followed by a review of current construction applications, along with present developments in asphalt mix production for pavement applications; whilst also documenting the technical development of Vegetex from exploratory laboratory work through to laying trials outlining, whilst also summarising, key features and benefits, current intellectual property status and environmental considerations. Following an in depth laboratory analysis, numerous full scale manufacturing trials were carried out. Work has shown that partial substitution of bitumen with used vegetable oil (UVO) can produce a wide range of standard binder grades, that comply with BS EN requirements for paving grade bitumen and that meet Sector Scheme 14 requirements thus enabling the product to comply with quality management systems. It has been shown that Vegetex material composites manufactured using traditional asphalt plants, delivery vehicles and laying equipment as currently used by the asphalt industry, retains similar or improved performance in compaction,

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Hong, Wan Yun. "Development and optimisation of regenerative adsorbent structures for carbon dioxide and contaminants removal." Thesis, University of Bath, 2017. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.723308.

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This thesis presents the research on the development and optimisation of energy efficient adsorbent monoliths and foam-monoliths for the removal of carbon dioxide (CO2) and other contaminants such as hydrogen sulfide (H2S) and water (H2O) vapour from the biogas stream. Zeolite and MIL-101(Cr) monoliths and carbonate-based zeolite foammonoliths of novel chemical formulations have been manufactured, characterised and tested for adsorption. Using the prepared adsorbent monoliths as models, their kinetic adsorption and gas flow dynamic performances have also been evaluated and compared with packed beds of commercially available adsorbent beads. The research mainly comprised of three parts. The first part was concerned with the manufacturing, characterising and optimising the adsorbent monoliths and foammonoliths. The adsorbent monoliths and foam-monoliths have been fabricated successfully using the unique paste extrusion technique described in this thesis. This includes monoliths of 13X zeolite, LiLSX zeolite, 5A zeolite, clinoptilolite and MIL-101(Cr) and foam-monoliths of K2CO3/13X zeolite and Na2CO3/13X zeolite. The incorporation of a decomposable pore former such as Licowax C micropowder PM into their paste formulations were found to improve their structural porosity, adsorption performance and mass transfer. It has been found that the best type of adsorbent structure for CO2 adsorption were 13X zeolite and purified MIL-101(Cr) monoliths and K2CO3/13X zeolite foam-monoliths. The CO2 adsorption performances of purified MIL-101(Cr) monoliths and K2CO3/13X zeolite foam-monoliths have been shown to be comparable to a packed bed of 13X zeolite beads (in terms of effectiveness of the adsorbent bed utilisation and equilibrium adsorption capacity on mass basis, respectively). This confirmed that the prepared adsorbent monoliths and foam-monoliths were potential adsorbent structures for CO2 adsorption. The second part involved testing the prepared adsorbent monoliths and foammonoliths with single (such as CO2, CH4 and H2S) and mixed (such as CO2/CH4 and CO2/CH4/H2O vapour) gases under different operating conditions to assess their dynamic adsorption performances for biogas upgrading. 13X zeolite and MIL-101(Cr) monoliths and K2CO3/13X zeolite foam-monoliths were used as model adsorbent structures in single and mixed gas adsorption experiments. The study has shown that 13X zeolite monoliths and K2CO3/13X zeolite foam-monoliths have excellent adsorption performances for CO2, H2S and H2O vapour and they could upgrade the biogas to a high quality (i.e., up to about 98% vol. CH4). For purified MIL-101(Cr) monoliths, it was discovered that they have relatively good adsorption performance for CO2, H2S, CH4 and H2O vapour and they could upgrade the biogas to a moderate quality (i.e., up to about 67% vol. CH4). In both humid and dry conditions, K2CO3/13X zeolite foam-monoliths were found to have the highest selectivity of CO2 over CH4 compared to 13X zeolite and purified MIL-101(Cr) monoliths. The third part was related to the evaluation and comparison of kinetic adsorption and gas flow dynamic performances of the prepared adsorbent monoliths with those of packed beds of adsorbent beads. In these studies, LiLSX zeolite monoliths and beads were used as model adsorbent structures. The kinetic adsorption study has discovered that LiLSX zeolite monoliths have slightly higher overall mass transfer resistance than packed beds of LiLSX zeolite beads. It has been shown that the overall mass transfer resistance in monoliths could be reduced by decreasing the channel diameter and increasing the wall thickness. The gas flow dynamic study found that the mass transfer in monoliths was not contributed by the axial dispersion of gases and this was in contrast to the mass transfer in packed beds. LiLSX zeolite monoliths were found to have lower pressure drop compared to packed beds of LiLSX zeolite beads. This showed that the biogas upgrading process would be more energy efficient using adsorbent monolith/foammonolith systems compared to packed bed systems.

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Muth, Karen [Verfasser], Christina [Akademischer Betreuer] Dornack, Christina [Gutachter] Dornack, Andrea [Akademischer Betreuer] Heilmann, Andrea [Gutachter] Heilmann, and Frank [Gutachter] Scholwin. "Modellgestütztes Monitoring von Störungen der Prozessbiologie in Biogasanlagen / Karen Muth ; Gutachter: Christina Dornack, Andrea Heilmann, Frank Scholwin ; Christina Dornack, Andrea Heilmann." Dresden : Eigenverlag des Forums für Abfall- und Kreislaufwirtschaft, 2018. http://d-nb.info/1226813666/34.

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Muth, Karen [Verfasser], Christina [Akademischer Betreuer] Dornack, Christina Gutachter] Dornack, Andrea [Akademischer Betreuer] Heilmann, Andrea [Gutachter] Heilmann, and Frank [Gutachter] [Scholwin. "Modellgestütztes Monitoring von Störungen der Prozessbiologie in Biogasanlagen / Karen Muth ; Gutachter: Christina Dornack, Andrea Heilmann, Frank Scholwin ; Christina Dornack, Andrea Heilmann." Dresden : Eigenverlag des Forums für Abfall- und Kreislaufwirtschaft, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa2-318699.

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Fajemidupe, Olawale Taye. "Effect of particle size on sand deposition in single-phase and multi-phase pipelines." Thesis, Cranfield University, 2016. http://dspace.lib.cranfield.ac.uk/handle/1826/12325.

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Sand production in the life of oil and gas reservoirs is inevitable, as it is co- produced with oil and gas from the reservoirs. Sand deposition in petroleum pipelines poses considerable risk to the production of oil and gas. This study investigates the effect both of sand particle diameter and concentration on minimum transport conditions in single phase and multiphase horizontal pipelines through experimental methods. This study defines the minimum transport condition (MTC) for sand grains under stratified two-phase flow regimes, as the combined minimum gas and liquid velocities at which all sand particles have sufficient energy to keep them moving in the liquid phase along the pipe. In this study, careful analyses based on experimental observations were made producing several conclusions. Based on the analysis, it was found that sand of different particle diameters and concentrations exhibits similar behaviours in single phase flow and stratified two-phase flow in horizontal pipes. Furthermore, in stratified two-phase flow, sand particles were transported within the liquid film and never observed crossing into the gas phase or transported across the gas- liquid interface; however, an increase in gas velocity tends to cause an increase in liquid velocity which in turn increases the velocity of the sand particles in stratified two-phase flow. Studies carried out on the effect of particle diameter and concentration on MTCs in both single phase (water) and stratified two-phase flows (air-water) in horizontal pipes showed that MTC increases with increases in particle diameter for the same concentration and also increases as the concentration increases for the same particle diameter. Sand sensors were used in this study for the purpose of sand monitoring and detection in single phase (water) and stratified two-phase flow in horizontal pipes. The sensors were flush-mounted at the bottom of the pipe. These sensors are commonly used to measure the thickness of a film in multiphase flow but have not been used before for monitoring and detecting sand both in single phase and multiphase flows. In this work the sensors were applied in monitoring and detecting sand in single phase and multiphase flows; they were found to be capable of monitoring and detecting sand in a conducting liquid in both single phase and stratified two-phase flows. Measured pressure gradients for sand-water flow at MTC were compared with measured pressure gradients for sand-air-water flow for the same particle diameter and concentration; it was found that there was a difference between the two pressure gradients. The pressure gradient of sand-water flow at MTC was higher than the pressure gradient of sand-air-water flow at MTC. For this reason, King et al.’s (2001) pressure gradient approach cannot be used to design wet gas pipelines. Modified concentration (v/v) correction correlation is proposed to predict sand transport at MTC in air-water. The correlation accounts for low concentration of sand (5.39E-05 to 4.90E-04v/v) in air-water flow. The proposed correlation predicted fairly when compared with the experimental results at MTC.

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Lokesh, A. "Studies on biodiesel production from local tree species oil and consequent ecological impact in rural Karnataka." Thesis, Coventry University, 2014. http://curve.coventry.ac.uk/open/items/ae50cedd-5843-40ba-ad16-3b945e097be0/1.

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The Government of India has planned to substitute 20% (12-15 million metric tonnes) of fossil diesel with biodiesel, produced using non-edible oils by 2017. In addition to Jatropha, more than 300 oil-bearing trees have been identified as biodiesel feedstock in India, of which, around 800 species inhabit Karnataka State.

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Abu, Bakar Muhammad. "Catalytic intermediate pyrolysis of Brunei rice husk for bio-oil production." Thesis, Aston University, 2013. http://publications.aston.ac.uk/20899/.

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Rice husks from Brunei were subjected via intermediate pyrolysis for bio-oil production. Two main objectives were set out for this study. The application of intermediate pyrolysis on Brunei rice husk for the production of bio-oil is the main objective of this experiment. Characterisation of the rice husks was inclusive as a pre-requisite step to assess the suitability as feedstock for production of liquid fuels. Following on from the characterisation results, a temperature of 450°C was established as the optimum temperature for the production of bio-oil. A homogenous bio-oil was obtained from the pyrolysis of dry rice husk, and the physicochemical properties and chemical compositions were analysed. The second objective is the introduction of catalysts into the pyrolysis process which aims to improve the bio-oil quality, and maximise the desired liquid bio-oil properties. The incorporation of the catalysts was done via a fixed tube reactor into the pyrolysis system. Ceramic monoliths were used as the catalyst support, with montmorillonite clay as a binder to attach the catalysts onto the catalyst support. ZSM-5, Al-MCM-41, Al-MSU-F and Brunei rice husk ash (BRHA) together with its combination were adopted as catalysts. Proposed criterions dictated the selection of the best catalysts, subsequently leading to the optimisation process for bio-oil production. ZSM-5/Al-MCM-41 proved the most desirable catalyst, which increases the production of aromatics and phenols, decreased the organic acids and improved the physicochemical properties such as the pH, viscosity, density and H:C molar ratios. Variation in the ratio and positioning of both catalysts were the significant key factor for the catalyst optimisation study.

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Al-Hadhrami, Munira. "Investigations into heavy oil recovery by vapour extraction (VAPEX)." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/25004.

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It is anticipated that resources from extra-heavy oils and bitumen may resolve the expected future escalation in oil demand. Such oils are usually recovered by thermal methods, however these can be energy intensive, especially for reservoirs with thin net-pay or those bounded with large aquifers or gas caps. This is primarily due to excessive heat losses. On the other hand, VAPour EXtraction of heavy oil (VAPEX) is a more energy-efficient, economically attractive and pollution-free alternative, especially for these problematic scenarios. Despite all the potential benefits of this process, there are many uncertainties associated with the actual physics of the process. The question as to whether the oil drainage rates are sufficient for the mechanism to be economically feasible for field scale application remains unanswered. Prediction of field scale recovery factors by numerical simulation is challenging since a very fine grid is needed to ensure that the physical diffusion dominates the numerical diffusion and then to model the subsequent gravity drainage. Thus, there is a tendency to rely upon the Butler-Mokrys (1989) analytical equation to estimate oil rates. A further uncertainty in field scale application, which has only been investigated in a few studies, is the impact of geological heterogeneity on the process, since this can influence the solvent-oil dispersive mixing as well as the shape of the solvent chamber. This research first investigated the oil drainage rates with VAPEX by performing a series of laboratory experiments in both homogenous and heterogeneous systems (including layered and single discontinuous shales). All experiments were performed in well-characterized glass bead packs using glycerol and ethanol as analogues of heavy oil and solvent, respectively. The porous medium and fluid properties were measured independently. The experimentally measured rates were compared to the estimates derived from the Butler-Mokrys (1989) analytical model. In addition, numerical simulations were performed to validate whether the physical diffusion boundaries were captured correctly. Our experiments revealed that the Butler-Mokrys analytical model substantially underestimated the drainage rates in all cases, even when the effects of convective dispersion and end-point density difference were factored in. Results from the heterogeneous models further suggested that layering may not reduce VAPEX oil drainage rates significantly. The performance in systems with layers and discontinuous shale barriers, however, was less than in homogenous models with higher or equivalent permeabilities. The numerical simulations, therefore, under-predicted the physical oil drainage rates, although the pattern of solvent-oil distribution was correctly captured. The research was then extended from lab-scale experiments to field-scale numerical investigations, using a fine grid, high resolution model with realistic petro-physical properties. The solvent-oil PVT were based on real field properties. Three key criteria were examined: the oil production rates and the recovery factors that it is possible to achieve; the full range of static parameters influencing VAPEX, and; identification of the most sensitive parameters (i.e. reservoir thickness (h), vertical permeability (kv/kh) and average arithmetic permeability). In addition, we compared the performance of VAPEX against Steam Assisted Gravity Drainage (SAGD). These, field scale numerical simulations revealed that VAPEX oil extraction rates incorporating diffusional mixing alone were insufficient for the mechanism to be feasible. Although incorporating single-well tracer test (SWTT) dispersivities into the numerical simulations significantly improved the recovery rates, they still remained unacceptably low.

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Okafor, Emeka Joachin. "Modelling vaporizing fluid flow through porous media with applications to liquefied natural gas." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/11675.

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The problem of vaporizing flow of liquefied natural gas (LNG) through porous or penetrable media has received very little attention despite its importance in assessing the performance and risk-based safety of large membrane tank LNG ships under barrier leakages. In this work, a fluid flow model is proposed and used to analyse the vaporizing flow behaviour of LNG through soil and glass wool porous materials. Furthermore, a modified vaporizing liquid pool model is implemented and used to examine the problem of vaporizing LNG pool on non-penetrable solid substrates. We employed an explicit, finite difference and a fourth-order Runge-Kutta algorithms coded in FORTRAN to respectively solve the flow and pool models. Both models were successfully verified and validated by comparisons to experimental data, analytical solutions, and to predictions of a commercial software (TOUGH2). Results from the vaporizing flow and pool analyses demonstrate that, for some of the applications considered, the liquid is expected to reach considered threshold depths, seep through the porous layer and contact, contaminate and/or embrittle surrounding natural or engineered systems. For the specific application to LNG cargo containment systems (or cargo tanks), this work has shown that there are safety risks associated with LNG leakage, which are ultra-low temperature of the inner hull, cryogenic damage and subsequent failure of the cargo containment system. Thus, for any LNG membrane cargo containment system to continue to be safe and secure, the various structural members of the insulation system should be designed and equipped with new and improved materials that possesses the necessary mechanical and thermophysical properties to maintain and/or improve the critical temperature standard and low-temperature performance of these systems. Further work should consider additional experimental evidence in order to fully validate and establish that solution predictions by the proposed models are describing the actual physical effects.

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Sahasrabudhe, Mayuresh Arun. "Determining the combustion kinetics of vegetable oil based fuels." Thesis, Heriot-Watt University, 2014. http://hdl.handle.net/10399/2832.

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In last few years’ interest in application of Bio Diesel as an alternative fuel in commercial diesel engines has been increased. However, combustion kinetics is required to predict and model combustion performance of a fuel. The chemical kinetic mechanisms are available for hydrocarbon (C4 to C16) combustion, but not for commercial Biofuel’s combustion. The aim of this research work is to investigate combustion kinetics of Rapeseed oil Methyl Ester (RME) by experimentally in Jet Stirred Reactor and modeling using CHEMKIN a software package at 1 and 10 bar for different fuel conditions. Rapeseed Oil (RSO) combustion kinetics will also be predicted using related theory and chemistry difference between RME and RSO. RME oxidation experiments and comparison with commercial Diesel showed that RME oxidation performance was better at fuel-lean conditions and higher temperatures in terms of profile trends of pollutants, especially at higher pressure suggesting higher Air/Fuel ratio is more suitable for RME combustion. RME oxidation was simulated taking unique approach of using surrogate fuels (nhexadecane, Methyl Acetate) as a model fuel, and RME as a model fuel. The surrogate fuel model results showed that oxidation of commercial biodiesel like RME can be simulated using surrogate model-fuels, but with some limitations and less accuracy. The modeling with RME as model fuel gives good agreement between the model and experimental data in terms of profile trends of key oxidation components. However model needs improvement at high pressure (10 bar). The RME reaction mechanism consists of 496 species and 2652 reversible reactions. The chemical kinetic mechanism for RSO oxidation is represented by Oleic acid (C18H34O2) oxidation. The reaction mechanism consists of 485 species and 2531 reversible reactions. The model is validated against RME oxidation data. The model is able to produce to reproduce profile trends of key oxidation components with some discrepancy.

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Abbas, Syed Zaheer. "Modelling of sorption enhanced chemical looping steam reforming (SE-CLSR) of methane in a packed bed reactor." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/15200/.

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In the sorption enhanced steam methane reforming (SE-SMR) process, hydrogen (H2) can be produced in concentration up to 98 vol. % (dry basis) in a single reactor packed with a mixture of reforming catalyst and carbon dioxide (CO2) sorbent. This is defined as pre-combustion capturing of CO2 and the high purity H2 produced can be used as a fuel for electricity generation, synthesis of ammonia-derived fertilisers, or hydrotreating of naphtha and other heavy gas oil in petroleum refinery. A cyclic operation between the production of H2 and regeneration of CO2 sorbent is required, but the energy demand for the sorbent regeneration is high. A proposed method to decrease this energy demand is to couple SE-SMR with chemical looping (CL), which naturally separates the nitrogen (N2) from the syngas via the highly exothermic cyclic oxidation with air of a metallic material, which acts as the reforming catalyst when reduced (oxygen transfer material or ‘OTM’). The combination of SE-SMR and CL makes the process energy efficient and eliminates the need for (i) high temperature as compared to the conventional steam methane reforming (SMR) process (typical temperature range is 750- 950°C), (ii) the water gas shift (WGS) reactors downstream of the reformer, and (iii) external heating using the natural gas fuel in the reformer. However the H2 generation of a high purity from one reactor operation is intermittent, as part of a cyclic operation, with the reactor alternately operating in Fuel Reactor mode (FR), with fuel and steam feed or Air Reactor mode (AR), with air feed. Adsorption of CO2 shifts the equilibrium of reaction towards more H2 production and ultimately increases the efficiency of the process towards H2 production. Production of H2, CH4 conversion and overall efficiency of the process depend upon many operating parameters. The effects of inlet temperature, reactor pressure, molar steam to carbon ratio (S/C) in the feed, and gas mass velocity on the SE-SMR and the sorption enhanced chemical looping steam reforming (SE-CLSR) of methane processes is reported in this thesis. The formulation of the SE-CLSR process model requires the modelling of packed bed reactors. This mathematical modelling covers various individual models (sub-models) for; SMR, SE-SMR, OTM reduction and oxidation of reduced OTM. The gPROMS model builder 4.1.0® is used to solve the model equations. In this work, an experimental IV kinetics study and model of SMR process over 18 wt. % NiO/α-Al2O3 catalyst are presented for an adiabatic fixed bed reactor in the temperature range of 300-700°C at 1 bar pressure. The model is validated by comparing the results with the experimental data obtained as part of this work. The simulation results are in excellent agreement with the experimental results. The equilibrium results are generated using Chemical Equilibrium with Applications (CEA) software. The effect of various operating parameters (temperature, pressure and S/C) on the CH4 and water conversion (%) is modelled and compared with the equilibrium values. The mathematical model of SE-SMR was developed based on the industrial operating conditions of temperature and pressure. The 873-973 K was found to be the optimum range of temperature, under the high pressure (30 bar) conditions, for the production of H2 of purity exceeding 85%. The developed model of SE-SMR was validated against the literature data. The mathematical model of SE-CLSR process was developed under adiabatic conditions. This model is the combination of reduction of catalyst followed by oxidation of the reduced catalyst. The individual models of reduction and oxidation are developed by using kinetic data available in the literature and later on validated with experimental results proposed in the literature. The already developed model of SE-SMR process is combined with the OTM reduction model to mimic the dynamic process occurring in the fuel reactor (FR) system. This FR is combined with air reactor (AR) and the combined model is run for 10 cycles. The sensitivity of the process is studied under the various operating conditions of temperature (873-1023 K), pressure (1-30 bar), molar S/C (2-6) and mass flux of the gas phase (Gs = 2-7 kg m-2 s-1). In this work, the operating conditions used for the production of H2 represent realistic industrial production conditions. The sensitivity analysis demonstrates that the developed model of SE-CLSR process has the flexibility to simulate a wide range of operating conditions of temperature, pressure, S/C and Gs.

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15

Eze, Valentine Chinaka. "The use of mesoscale oscillatory baffled reactors for rapid screening of heterogeneously catalysed biodiesel production reactions." Thesis, University of Newcastle upon Tyne, 2014. http://hdl.handle.net/10443/2444.

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Biodiesel is a renewable alternative to petro-diesel, derived from vegetable oils and animal fats. The use of biodiesel in place of petro-diesel leads to reduced emissions of greenhouse gases, especially CO2, and ensures energy security. The most commonly used technology for biodiesel production is based on a homogeneously catalysed liquid phase reaction. The disadvantages of this process are the ongoing costs of catalyst replacement, the large number of downstream purification steps and production of low quality glycerol with consequently low market value. In principle, heterogeneous catalysts can solve these problems. This research demonstrates that homogeneous alkali-catalysed biodiesel production was possible at an industrially acceptable level of conversion (> 96%) in ~ 5 min residence time, requiring a combination of high catalyst concentration and good mixing. Both the experimental and model simulations results clearly showed that rapid biodiesel production (reaction times below 2 min) at economically viable conversions can be achieved by increasing base catalyst and methanol concentrations without significant problems due to excess soap formation, even in the presence of water and free fatty acids. A heterogeneous strontium zirconate based (SZB) catalyst showed substantial activity towards rapeseed oil transesterification, but there was significant loss in activity with or without the presence of water due to leaching of the active sites, Sr(OH)2, into the methanol phase. The SZB catalyst cannot be re-used for triglyceride transesterification, as it acts in a similar manner to conventional homogeneous alkali catalysts. A PrSO3H-SBA-15 catalyst was active for carboxylic acids esterification with methanol, with the reaction rates increasing with reaction temperature and methanol molar ratio, but decreasing with water content and carboxylic acid chain length. Steric effects increased with carboxylic acid chain length, causing reductions in the esterification rates and turnover frequency. PrSO3H-SBA-15 has very narrow pores (5.1nm) that are not large enough for significant triglyceride transport. Therefore, PrSO3H-SBA-15 with expanded pore size, functionalised on a hydrophobic support would be required for simultaneous esterification of free fatty acids and triglyceride transesterification. Finally, a mesoscale oscillatory baffled reactor (meso-OBR) was constructed and used to suspend and screen solid catalysts for transesterification and esterification reactions, significantly reducing reagent required and waste generated due to the small volume (~10mL). This work is the first example of systematic screening of a solid-liquid-liquid reaction system in a meso-OBR. Continuous screening in the meso-OBR permits detailed kinetic studies, rapid optimisation of reaction conditions, and assessment of the reusability of the catalyst in a single experiment as opposed to multiple experiments in conventional batch reactor screening.

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16

Puthiyapura, Vinod Kumar. "Development of anode catalysts for proton exchange membrane water electrolyser." Thesis, University of Newcastle upon Tyne, 2014. http://hdl.handle.net/10443/2446.

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The proton exchange membrane water electrolyser (PEMWE) is a promising technology for the production of hydrogen from water. The oxygen evolution reaction (OER) has a high over potential cf. with the hydrogen evolution reaction and is one of the main reasons for the high energy demand of the electrolyser. RuO₂ and IrO₂ are the most active catalyst for OER, but are costly, making the electrolyser system expensive. In general, it is important to use stable, active and cheap catalysts in order to make a cost efficient electrolyser system. Supporting the active catalyst on a high surface area conducting support material is one of the approaches to reduce the precious metal loading on the electrode. Antimony tin oxide (ATO) and indium tin oxide (ITO) were studied as possible support materials for IrO₂ in the PEMWE anode prepared by the Adams method. The effect of the support material on the surface area, electronic conductivity, particle size and agglomeration were investigated. The IrO₂ showed highest conductivity (4.9 S cm-¹) and surface area (112 m2 g-¹) and decreased with the decrease in the IrO₂ loading. Using the catalysts in the membrane electrode assemblies (MEA) with Nafion®-115 membranes, at 80°C showed that the catalyst with better dispersion and conductivity gave better performance. The unsupported IrO₂ and 90% IrO₂ supported on ATO and ITO showed the best performance among all the catalysts tested, achieving a cell voltage of 1.73 V at 1 A cm-². A lower IrO₂ loading decreased the conductivity and surface area. The IrO₂ particle size and bulk conductivity of the supported catalyst significantly influenced the MEA performance. Overall, it is important to maintain a conductive network of IrO₂ on the non-conducting support to maintain the bulk conductivity and thus reduce the Ohmic potential drop. Although RuO₂ is the most active catalyst for OER, it lacks stability on long term operation. RuxNb1-xO₂ and IrxNb1-xO₂ catalysts were synthesized and characterized, to try to develop stable electrodes for PEMWE. However the Adams method of catalyst synthesis formed a sodium–niobium complex making it unsuitable for preparation of Nb based catalysts. In both Adams and hydrolysis methods of synthesis, the addition of Nb ₂O₅ decreased the anodic charge and electronic conductivity of the catalyst due to the dilution of the active RuO₂. The RuO₂ catalyst showed the best performance in MEA evaluation compared to the bimetallic catalyst (1.62 V and 1.75 V @1 A cm-² for RuO₂(A) and RuO₂(H) respectively). A higher stability for bimetallic catalyst compared to the monometallic catalysts was obtained from the continuous CV cycling and MEA stability test.

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17

Ситнік, Наталія Сергіївна. "Удосконалення технології переетерифікування жирів з використанням гліцератів лужних металів". Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/23534.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.18.06 – технологія жирів, ефірних масел і парфумерно-косметичних продуктів. – Національний технічний університет "Харківський політехнічний інститут" Міністерства освіти і науки України, м. Харків, 2016. Дисертаційну роботу присвячено вирішенню конкретного науково-практичного завдання щодо розробки наукових засад технології переетерифікування жирів з використанням нових каталізаторів, які представляють собою гліцерати лужних металів. Визначено триацилгліцерольний склад початкових та переетерифікованих індивідуальних олій. Встановлено вплив переетерифікування з традиційним каталізатором на температуру плавлення олій. Обгрунтовано вибір тестового жиру для досліджень переетерифікування жирів. Доведено ефективність гліцерату калію та гліцерату натрію як каталізаторів переетерифікування жирів. Встановлено характер змін триацилгліцерольного складу тестового жиру у результаті переетерифікування у присутності гліцерату калію в порівнянні з промисловим каталізатором – метилатом натрію. Визначено термін зберігання гліцерату калію та виявлено можливість його регенерування після втрати каталітичної активності. Встановлено залежність каталітичної активності гліцерату калію від основних фізико-хімічних властивостей початкової сировини. Розроблено математичні моделі переетерифікування тестового жиру у присутності гліцерату калію в залежності від основних технологічних параметрів. Сформульовано рекомендації щодо вибору режимів та визначено раціональні умови переетерифікування. Доведено можливість застосування гліцерату калію у виробництві якісних переетерифікованих жирів із сумішей олій та жирів. Проведено економічні розрахунки собівартості гліцерату калію. Розроблено удосконалену технологію хімічного переетерифікування жирів з використанням гліцератів лужних металів. Розроблено проект технологічної інструкції на виробництво жирів переетерифікованих з використанням гліцератів лужних металів.
Thesis for a candidate degree of technical sciences by specialty 05.18.06 – fats, essential oils and perfume-cosmetic products technology. – National Technical University "Kharkov Polytechnic Institute" Ministry of Education and Science of Ukraine, Kharkov, 2016. The thesis is dedicated to specific scientific and practical task to develop the scientific foundations of fat interesterification technology using new catalysts that constitute alkali metals glycerates. Triacylglycerol composition of initial and interesterified samples of individual oils was defined. The influence of interesterification with traditional catalyst to the melting point of oils was installed. The choice of test fat for studies of fat interesterification was grounded. The efficiency of potassium glycerate and sodium glycerate as catalysts for interesterification of fats was proved. The character of triacylglycerol composition changes of test fat in the process of interesterification in the presence of potassium glycerate compared with industrial catalyst sodium methylate was installed. Shelf life of potassium glycerate was defined and the possibility of recovery after the loss of catalytic activity was revealed. The dependence of the catalytic activity of potassium glycerate on basic physical and chemical properties of the original material was installed. The mathematical model of the interesterification of test fat in the presence of potassium glycerate depending on the basic technological parameters was developed. Recommendations on the choice of modes were formulated and rational conditions of the interesterification were defined. The possibility of potassium glycerate use in the production of qualitive interesretified fats with mixtures of oils and fats was proved. Economic analysis of the cost potassium glycerate was conducted. The advanced chemical fat interesrerification technology using alkali metals glycerates was developed. The project of technical regulations for production of interesretified fats using alkali metals glycerates was developed.

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18

Al-Megren, Hamid. "Hydrodenitrogenation of pyridine over bulk and supported molybdenum carbide." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249636.

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19

Mogford, Robin. "The effect of polymer chain architecture on the adsorption and dispersion properties of functionalised oligomers." Thesis, University of Bristol, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271741.

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20

Tay, Boon Li. "Forces on pipe bends due to intermittent gas-liquid flow." Thesis, University of Cambridge, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289501.

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21

Lange, Thomas, and Frank Gutte. "Explosionsschutz an Biogasanlagen: Stand der Sicherheitstechnik bei Biogasanlagen bezüglich möglicher Explosionsgefährdungen und Empfehlungen zu daraus abzuleitenden Schutzmaßnahmen." Sächsisches Landesamt für Umwelt, Landwirtschaft und Geologie, 2016. https://slub.qucosa.de/id/qucosa%3A8004.

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Der Stand der Sicherheitstechnik beim Explosionsschutz an Biogasanlagen mit erweiterter Peripherie wurde einer aktualisierten Bewertung unterzogen. Ergänzend zum »Stand der Technik«, basierend auf der DGUV 113-001, wurden Empfehlungen erarbeitet, um den Stand der Sicherheitstechnik zur Gewährleistung des Explosionsschutzes an Biogasanlagen weiter zu erhöhen.

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22

Murray, Matthew C. "Examining post-evacuation plans for hurricane evacuees using Westerly, Rhode Island as a test case." Muncie, Ind. : Ball State University, 2009. http://cardinalscholar.bsu.edu/665.

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23

Chen, Yinglong. "Optimization of Scleroderma spore inoculum for Eucalyptus nurseries in China." Chen, Yinglong (2006) Optimization of Scleroderma spore inoculum for Eucalyptus nurseries in China. PhD thesis, Murdoch University, 2006. http://researchrepository.murdoch.edu.au/665/.

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Scleroderma, a genus of ectomycorrhizal (ECM) fungi, is often associated with trees in disturbed habitats and is therefore considered to be suitable for use in plantation forestry. This study investigated aspects of Scleroderma and its mycorrhizas with the view to its future use in plantation forestry in south China. Spores were chosen as inoculum as they are preferred by nursery managers in south China, due to the lack of on-site fermentation and storage facilities. To determine the need for inoculation, Eucalyptus plantations in south China were sampled for sporocarps and mycorrhizas over two years. This study revealed a low diversity of ECM fungi consisting of 15 taxa fruiting beneath Eucalyptus plantations. The most common genera were Scleroderma and Pisolithus, but they were infrequent and the extent of root colonization was poor. Bioassay trials with E. urophylla as a bait host, using soils collected from 8 eucalypt plantations, confirmed low levels of inoculum in field soil. It was concluded that introduction of suitable ECM symbionts into eucalypt nurseries in south China is desirable in the future. As the Scleroderma genus has not been well studied in Australasia or SE Asia, over 140 collections gathered mainly from eucalypt plantations in south China and south-western Australia were described using sporocarp and spore morphology. Twelve Scleroderma taxa were recognized from collections made from under eucalypt plantations in south-western Australia and 6 of these were collected from under eucalypt plantations in south China. In conjunction with classical taxonomy, 30 collections, including those used in inoculation trials, were further characterized by phylogenetic analyses of ITS or LSU rDNA sequences. These studies supported classical delineation of some Scleroderma species but not all. Although a limited number of collections were amplified, phylogenetic results showed that most collections in this study were distinct from the European and Malaysian taxa extracted from GenBank (89% bootstrap support for both LSU and ITS regions). In order to optimise spore germination and root colonization, two glasshouse trials were established to examine suitable spore density and spore storage conditions on E. globulus and E. urophylla. A spore density of 105 spores seedling-1 was identified as a suitable dose for promoting root colonization. Spores stored for 5 years at low temperate (4 0C) were almost as effective as freshly collected spores in forming mycorrhizas. As the compatibility of Scleroderma fungi with plantation trees is unknown, a glasshouse experiment examined the ability of 15 collections of Scleroderma to form mycorrhizas with seedlings of six plantation trees (Acacia mangium, A. mearnsii, E. globulus, E. urophylla, Pinus elliottii and P. radiata) in a nursery potting mix. Most collections were able to aggressively colonize eucalypts and pines, while roots of acacias were poorly colonized. As the Australian collections were more effective in colonizing short roots on eucalypts than the Chinese collections, it was concluded Scleroderma should be sourced from outside China for inoculating eucalypts in Chinese nurseries. To optimize nursery practices to meet the demand for high quality seedlings and clonal lines of E. urophylla and hybrids, for outplanting in south China, effects of rooting medium and inoculation with 6 Scleroderma collections on the growth of E. urophylla were examined in a nursery in south China. Four types of soil taken from eucalypt plantations in south China were compared to a potting mix composed of vermiculite, peat and sand. The inoculant Scleroderma fungi were able to out-compete indigenous mycorrhizal fungi in the rooting media. However, the potting mix was superior to soils both for plant growth and ECM development under nursery conditions. This research should facilitate the use of Scleroderma spores in eucalypt nurseries in south China. Spore orchards could be set up in China using Australian Scleroderma spp. from under eucalypts. Spores could be stored dry at 4 0C until they are required for inoculation in potting mixes in containerized nurseries. However, before commercial application, further work on persistence of Scleroderma in the nursery and field, and responses of trees in the field to inoculation, needs to be undertaken.

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24

Long, Maebh. "Derrida and a theory of irony : parabasis and parataxis." Thesis, Durham University, 2010. http://etheses.dur.ac.uk/665/.

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This thesis presents a theory of structural irony gleaned from the irony theorised and performed in the texts of thinkers whose works operate on the border of the (non)propositional: Plato, Friedrich Schlegel, Maurice Blanchot, Paul de Man, Emmanuel Levinas and Jacques Derrida. While focusing on the irony performed in the texts of Jacques Derrida, and using his engagements with these thinkers as a frame, this is not a theory of “Derridean” irony, but an irony (primarily) elaborated through a deconstructive approach and vocabulary. Structural irony is seen to take the form of the transgressive step/counter-step of parabasis and the non-hierarchical disorder of parataxis. It is an anacoluthic force/weakness, and exhibits the conjunctive/disjunctive trait of hyphenation. It is neither of cynical, aesthetic distance nor humorous, parodic engagement, but is a productive movement of (impossible) negotiation between terms. Irony is an expression of the beyond, within, and this reworking of borders and limits is performed in the fragment/aphorism. The (ir)responsible step taken in Derrida’s texts is understood as a mode of structural irony, and it is proposed that the stylistic changes that occurred in Derrida’s “later” texts were in part due to the autoimmunity caused by an overexposure to the “laws of the interview”. Throughout the thesis styles that manipulate the unmasterable excesses of irony are investigated, and each chapter ends with a reading of one of Derrida’s more “literary” or “performative” texts, while recognising and playing with the falsity of such generic makers or divisions. Inscribing Derrida within a tradition of thinkers of the non-thetic both extends readings of that tradition and of irony itself, while affording a valuable way of approaching the “structures” within Derrida’s texts. Irony is not presented as the transcendental signifier of deconstruction, but as a profitable way of understanding deconstruction and its relation to other writers.

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25

Homewood, Christopher James. "From Baader to Prada : the representation of urban terrorism in German-language film." Thesis, University of Leeds, 2008. http://etheses.whiterose.ac.uk/665/.

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This study analyses the response of filmmakers to the left-wing terrorism of the Red Army Faction (RAF) experienced by West Germany in the 1970s, and its legacy. At the height of its activity, the RAF violently shook the foundations of postwar German democracy with a string of politically motivated attacks against the Federal Republic which brought the state's democratic credentials into question. The first part of this thesis considers the intervention of the New German Cinema on the underlying political crisis that the RAF unleashed, examining the filmmakers' attempt to catalyze a labour of mourning which connected contemporary left-wing terror to the unresolved legacies of the Nazi past, but which the state had tried to close down. Ultimately, however, the filmmakers were unable to contest a wave of contemporary repression which threatened to engulf the memory of the RAF, and so by the mid-1980s, when not altogether forgotten, a dominant consensual understanding of the immediate past which spoke from the perspective of the state had been set. However, in recent years there has been a renewed explosion of interest in this brief yet turbulent period in history, at the vanguard of which has stood the nation's filmmakers. The second part of this examines how postunification filmmakers have responded to this ostensibly dead socio-political and, for artists, aesthetic phenomenon. I examine how new films have engaged recent cultural implications and manifestations (such as the `Prada-Meinhof' clothing phenomenon) of the terrorist legacy and seek to innovate the ideologically entrenched cultural terms of remembrance which had settled around the group in order to offer a more nuanced, complex reading of the past.

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26

Pezzano, Pietro. "La progettazione e la verifica di pavimentazioni stradali rinforzate innovative." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amslaurea.unibo.it/665/.

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La tesi è uno studio di diversi metodi di rinforzo delle pavimentazioni stradali, diversi per materiali utilizzati e progettazione dell’intervento. Partendo da una ricca Case History fino a giungere al caso specifico dei lavori di rafforzamento e ripristino della sovrastruttura stradale della S.S. n° 67 “Tosco- Romagnola”.

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27

Dhamotharan, Mogana. "Open learning systems for the continuing education of professionals in Malaysia." Thesis, Connect to e-thesis, 1988. http://theses.gla.ac.uk/665/.

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28

Calvia, Valentina <1980&gt. "Cellule staminali, immortalità e enhancement." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/665/.

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29

Abdalaziz, Mohamed. "Measuring taxable capacity in Libya." Thesis, University of Gloucestershire, 2012. http://eprints.glos.ac.uk/665/.

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This thesis measures the tax effort and taxable capacity in Libya and examines an important research question: " Has the tax burden reached the level of full tax capacity in Libya?". The main motivation of the study is the need to diversify the sources of the Libyan economy. To this end the thesis presents a conceptual framework for tax burden, excess of tax burden, theory of optimal taxation, concept of taxable capacity, concept of tax effort. The framework is used to reviews the developments of the Libyan economy and the impact on tax effort. The thesis has explored several aspect of tax performance in Libya. First, it analyses the trends of public revenues, public revenues, public spending in final stances of the government. Second, it studies the tax structure and the relative importance of tax sources through the analysis of marginal propensity to tax and the income elasticity of taxes. Third, it examines the evolution of Libya's tax system particularly the income tax system. Finally, various econometrics models such OLS regression, Ordinary ridge regression, and Unbiased ridge regression are used to measure the tax performance such as tax burden, tax effort and tax capacity using time series data covering 1970 to 2000, and panel data covering 2001 to 2007. A fixed and random effect model are used to compare if the determinants of Libya’s tax efforts differs from that of a range of selected oil producing countries. These countries are: Algeria, Argentina, Bahrain, Bangladesh, Bolivia, Botswana, Brazil, Cameroon, Chad, Chile, Colombia, Republic of Congo, Côte d'Ivoire, Equatorial Guinea, Ecuador, Egypt, Emirates, Ethiopia, Ghana, Guatemala, Guyana, Indonesia, Iran, Kenya, Kuwait, Lesotho, Libya, Mauritania, Nigeria, Oman, Peru, Saudi, Trinidad and Tobago, Tunisia, Venezuela, Yemen, Zambia, Zimbabwe. This research consists of seven chapters: Chapter One provides a background; Chapter Two provides the literature review; Chapter Three 4 gives a brief overview of the development of the Libyan economy, while in Chapter Four there is a description of the public finances in Libya; this is followed in Chapter Five by a review of the tax system in Libya; Chapter Six presents the study’s analyses and findings; Chapter Seven provides the conclusions and recommendations. The main findings of this research are: First, in Libya, tax burden per capita is high; Second, the tax bases in Libya were narrow reflecting the government's heavy reliance on oil revenue; Third, the level of taxable capacity in Libya is also low compared to the selected oil producing countries for a variety of reasons, including: narrow tax bases, failure to diversify the tax sources, and the public sector being subject to tax. The argument is presented that the Libyan economy has reached the full utilization of its taxable capacity. In addition, the study found that the following factors have a major positive impact on Libya's taxable capacity and tax effort: the national product of the service sector, money supply, level of business freedom, level of economic freedom, currency in circulation and tax penalties. In contrast, two factors are found to be negatively affecting the taxable capacity and tax effort in Libya: non-oil exports, oil revenues. The contributions of this study to the literature are twofold: first, this is the first of its kind to provide comprehensive analyses of Libya’s tax performance; Second, it has added some new variables such as oil revenues, non-oil exports, currency in circulation, money supply(M1), and tax penalties in testing the determinants of tax effort into the model built by previous researchers. Finally, the research results shed lights on how Libya government may diversify the Libyan economy and encourage growth in the non-oil private sector through proper taxation mechanisms.

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30

Donnelly, Mark. "Labour politics and the affluent society, 1951-1964." Thesis, University of Surrey, 1994. http://epubs.surrey.ac.uk/665/.

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Post-war affluence for a time appeared to threaten Labour's future as a party of government in Britain. After the Party's third consecutive election defeat in 1959 commentators suggested that the twinned growth of affluence and consumerism had begun to erode Labour's traditional base of support. It was argued that workers aspired to middle class values and lifestyles as they became more prosperous and as a consequence abandoned the Labour Party. Wilson's victory in 196A showed that predictions about the Party's long-term demise had been wide of the mark. But historians have continued to search for an explanation for Labour's apparent electoral weakness in the 1950s. This thesis will argue that the descriptions of weakness and failure which have been applied to the Labour. Party in the affluent post-war years have been overstated. It will aim to show that the underlying strength and vitality of the Party in the 1950s and early 1960s have been too often overlooked. After the aims of the thesis have been explained in more detail in the introduction, chapter two examines the internal politics of the Labour Party between the elections of 1951 and 1955. Policy-making during this period is also discussed. Chapter three focuses on Hugh Gaitskell's leadership of the Party between December 1955 and October 1959. Labour's three year review of policy is discussed in chapter four and it will be shown that this review provided the basis for the manifestos of 1959 and 1964. Chapter five will examine the Party's response to the 1959 election defeat. Chapter six is a discussion of policy-making between 1959 and 1964. Chapter seven assesses the internal opposition to the Labour leadership after 1955 and chapter eight is a discussion of local Labour politics during the thirteen years of opposition.

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31

Lippmann, Jens, Henriette Mietke-Hofmann, Jennifer Deichmann, and Thomas Heidenreich. "Bioaerosole aus Anlagen der Geflügelhaltung: Bestimmung und Beurteilung wichtiger Bestandteile des Bioaerosols in der Stall- und Abluft sowie im Stallumfeld (Luv/Lee) zur Bereitstellung von Kenndaten und Bewertung des Emissions- und Immissionsverhaltens mikrobieller Luftbestandteile aus Tierställen (Geflügel)." Sächsisches Landesamt für Umwelt, Landwirtschaft und Geologie, 2015. https://slub.qucosa.de/id/qucosa%3A8005.

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Der Bericht informiert über die Konzentration von Bioaerosolen in der Abluft und im Umfeld von Geflügelanlagen. Für die Parameter Endotoxin, Gesamtpilzzahl, Gesamtbakterienzahl, Enterokokken, Enterobakterien und S. aureus wurden Emissionsfaktoren berechnet sowie die Immissionskonzentration untersucht. Die Ergebnisse zeigen, dass es zu erhöhten Bioaerosolkonzentrationen im Umfeld von Geflügelanlagen kommen kann. Besonders der Parameter Gesamtbakterienzahl war deutlich erhöht. Die Untersuchungen wiesen Staphylokokken als hauptsächlich vorkommende Gattung nach. In mehreren Stichproben wurden hauptsächlich Staphylokokken der Risikogruppe 1 (RL 2000/54/EG) nachgewiesen. Dieser Beitrag richtet sich vor allem an Wissenschaftler und Fachpersonal auf dem Arbeitsgebiet der Bioaerosole.

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32

Taylor, Lisa Jane. "The film-forming and wear-reducing properties of antiwear additives." Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246920.

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33

Castro, Diaz Miguel. "Universal characterisation of coke structure and distribution for hydrocarbon conversion process catalysts." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268476.

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34

Bahri, Syaiful. "In situ combustion for upgrading of heavy oil." Thesis, University of Salford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248917.

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35

Jibril, Baba El-Yakubu. "Catalytic oxidative dehydrogenation of propane." Thesis, University of Salford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248905.

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36

Wallace, Carol Leigh. "The investigation into the formation of coke in relation to the fluid catalytic cracking process." Thesis, University of Strathclyde, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248295.

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37

Vant, Stewart Charles. "Investigation of fluid properties at non-ambient conditions." Thesis, University of Strathclyde, 2003. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=27056.

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A requirement for thermophysical property data of diesel fuels at conditions removed from ambient was identified. A series of measurements of the pressure-volume-temperature relations of diesel fuels was undertaken using a Micro-PVT apparatus at pressures to 300MPa in the temperature range 25 to 75°C. A new calibration procedure for this instrument was devised to enable measurements of high accuracy to be made. Viscosity measurements of diesel fuels over a range of temperature and pressure were made using the National Engineering Laboratory high pressure viscometer to pressures of 460MPa in the temperature range 25 to 100°C.Corresponding states theory was applied for compressed liquid density prediction. Improvement in density prediction in this region was found through use of iso-octane and heptadecane as reference fluids. Compressibility factors of these were represented by Tait-style equations. An iterative solution technique was developed to allow the corresponding states method to be applied to diesel fuelsusing limited density measurement and a guess value of boiling point as inputs. Densities predicted from this method agreed well with measurements made using the Micro-PVT apparatus. Hard sphere theory was applied as a method for viscosity prediction. Despite the complexity of the diesel fuel mixture, reasonable estimates of viscosity were made with limited measurement input at higher temperatures. At lower temperatures, an additional simple empirical correction term was required. A method of viscosity estimation of complex hydrocarbon mixtures based upon composition is presented. Further development of this would require additional measurements and greater characterisation of the fuel.

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38

Eow, John Son. "Electrostatic enhancement of coalescence of water drops in oil." Thesis, University of Surrey, 2002. http://epubs.surrey.ac.uk/842815/.

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Dispersed water drops in oils can cause detrimental effects. For example in refining and cracking of crude oil, poisoning of catalysts and equipment corrosion can be major problems due to the presence of water. Therefore there is a need to develop more efficient and cost-effective separators. The work in this thesis covers an investigation of the underlying electrostatic phenomena (i.e. drop-drop and drop-interface coalescence and drop deformation and break-up) leading to the development of compact electrocoalescer-separators. Using novel two-dimensional electrode systems, it is shown here that coalescence readily occurs when the electric field is applied in the same direction as the line joining the centres of the two drops, in line with the previous theoretical prediction of the maximum attractive force induced in this way. An adaptive Finite Element Method, incorporating automatic error and mesh generator programmes, has been used to quantify the electric-induced forces of charged spheres in an insulating medium, for short distances that are much smaller than the drop radius, where analytical solutions are no longer reliable. Moreover, drop-drop attraction can also occur when the angle is 125.3° from the electric field direction. Previous work suggests that pulsed d.c. fields are effective for low-aqueous-content systems, and this has been further investigated here. The applied electric field and pulse frequency can be optimised to achieve the highest coalescence rate. High electric fields (> 3.5 kV/cm) are shown to deform and break up aqueous drops when the electric field-induced stresses overcome the interfacial tension. A critical electrostatic Weber number, corresponding to the onset of drop break-up, has been evaluated to be about 0.49 for several aqueous-oil systems. For the separation of dispersed aqueous drops from an oil phase, it is advantageous to incorporate an aqueous layer to induce drop-interface coalescence. A suitably applied electric field is shown to give efficient drop-interface coalescence. The above investigations have led to the design and development of two compact electrocoalescer-separators. The first separator combines the effects of electrocoalescence and gravitational settling. The second separator, which utilises the electrocoalescence and centrifugal effects, can handle larger throughputs with reasonable separation efficiency. Both devices significantly enhance the separation and are good examples of how the fundamental understanding gained in this studies can be applied to realistic practical situations.

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39

Muth, Karen. "Modellgestütztes Monitoring von Störungen der Prozessbiologie in Biogasanlagen." Eigenverlag des Forums für Abfall- und Kreislaufwirtschaft, 2017. https://tud.qucosa.de/id/qucosa%3A31869.

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Der Ausbau von erneuerbaren Energien hat seit 2000, durch die Einführung des Erneuerbaren Energien Gesetzes, auch im Bereich Biomasse zu einem stetigen Ausbau von Biogasanlagen geführt. Seit ca. 2014 stagniert der Ausbau, aufgrund einer Neuauflage des EEGs, in dem einige Subventionierungen wegfallen. Aus diesem Grund liegt der Fokus momentan u.a. auf der Optimierung von Biogasanlagen und der Minimierung von Störungen (Über- oder Unterfütterung, Temperaturschwankungen, Rührwerksausfall, etc.). Eines dieser Störfaktoren ist der Mangel von Spurenelementen, der häufig beim Einsatz von nachwachsenden Rohstoffen auftritt. Häufig führt dieser Mangel zu einem niedrigen pH-Wert, einem hohem FOS/TAC Verhältnis sowie einer reduzierten Methanausbeute. Bleibt solch ein Mangel unentdeckt, kann es zu einem vollständigen Prozessabsturz innerhalb der Biogasanlage kommen. Die mathematische Beschreibung von anaeroben Prozessen erfolgt bereits seit ca. 40 Jahren und bildet den Biogasprozess mittlerweile sehr gut ab, sodass auf einige Störfaktoren rückgeschlossen werden kann. Durch eine Vielzahl existierender Modelle hat die IWA Task Group ein allgemeingültiges Modell zum anaeroben Abbau entwickelt, das Anaerobic Digestion Model No. 1 (Batstone et al. 2002). Aufbauend auf dem ADM1 sind weitere Modell-erweiterungen entwickelt worden. Eine Übersicht über diese Modelle ist in (Donoso-Bravo et al. 2011) zu finden. Bisher gibt es allerdings noch keinen Modellansatz zur Beschreibung der Spurenelemente innerhalb des ADM1 bzw. dessen Erweiterungen. Die vorliegende Arbeit beschäftigt sich mit dem Einfluss der Spurenelemente auf den Biogasprozess, insbesondere im Falle einer Mangelsituation. Dabei gab es zwei Hauptziele. Das erste Hauptziel der vorliegenden Arbeit war eine mathematische Beschreibung der Umwandlungsprozesse von Spurenelemente sowie deren unterschiedliche Bindungsformen bereitzustellen. Diese Beschreibung sollte als Modellerweiterung an ein vorhandenes Modell zum anaeroben Abbau angebunden werden. Mit Hilfe dieses Modells sollte sowohl der Konzentrationsverlauf als auch die durch die Spurenelemente verursachten Auswirkungen auf den Biogasprozess abgebildet werden. Das zweite Hauptziel war die Validierung des Modells durch parallel durchgeführte Laborversuche an Reaktoren zur Untersuchung des Spurenelementmangels. Mit Hilfe der Laborversuche sind die Auswirkungen eines Spurenelementmangels nachgewiesen worden. Dabei zeigte sich nach ca. 3 Monaten Laufzeit ein reduzierter pH-Wert, ein ansteigendes FOS/TAC Verhältnis sowie eine verzögerte Biogasproduktion. Ein vollständig stabiler Prozess hat sich erst durch die Zugabe aller Spurenelemente wieder eingestellt. Gleichzeitig hat die erneute Zugabe der Spurenelemente in die Testreihen nach dem Mangel zu einer starken Schaumbildung geführt. Die mathematische Beschreibung der Umwandlungsprozesse von Spurenelemente erfolgt als eigenständiges Modell und kann an beliebige Modellansätze integriert werden. In der Arbeit ist dafür das ADM1da ausgewählt worden, um eine Beschreibung der anaeroben Prozesse zu integrieren. Gleichzeitig beinhaltet das ADM1da die Beschreibung von Mischsubstraten, sodass mit dem entwickelten Modellansatz zu jedem Substrat die spezifische Spurenelementkonzentration angegeben werden kann. Das neu entwickelte Modell beinhaltet drei wesentliche Schritte: (1) den Abbau des Substrates, indem die Spurenelemente gebunden sind, (2) die Freisetzung der Spurenelemente in den Gärschlamm und (3) die Umwandlung der einzelnen Spurenelement-Bindungsformen untereinander. Dabei sind in dem Modellansatz vier Fraktionen bezüglich der Spurenelemente integriert: (a) freie (bioverfügbare) bzw. leicht gebundene Ionen, (b) adsorbierte Ionen, (c) in Biomasse gebundene SE und (d) ausgefällte SE. Die Beschreibung einzelner Reaktionen sowie die Umwandlungen innerhalb der verschiedenen Fraktionen erfolgt über die Petersen-Matrix.:Danksagung I Inhaltsverzeichnis II Abbildungsverzeichnis IV Tabellenverzeichnis IX Abkürzungsverzeichnis XI 1 Einleitung 1 2 Kenntnisstand 4 2.1 Allgemeiner Aufbau Biogasanlagen 4 2.2 Grundlagen des anaeroben Abbaus 6 2.2.1 Biologische und chemische Prozesse 7 2.2.2 Einflussfaktoren 10 2.3 Spurenelemente 14 2.3.1 Bedarf und Folgen auf den Gärprozess 14 2.3.2 Bioverfügbarkeit von Spurenelementen 16 2.3.3 Quellen – Substrate und Zuschlagstoffe 17 2.4 Anaerobmodelle 18 2.4.1 Allgemein 18 2.4.2 ADM1 – mathematische Beschreibung der wichtigsten Prozesse 20 2.4.3 Weiterentwicklungen des ADM1 Modells 22 2.4.4 Verbesserungsmöglichkeiten am ADM1 Modell 24 2.4.5 Modellierung der Spurenelemente 26 3 Wissenschaftliche und experimentelle Methodik 29 3.1 Versuchsanlage 29 3.2 Versuchsdurchführung 31 3.3 Analysemethoden/Messtechnik 35 4 Auswertung und Diskussion der Laborversuche 38 4.1 Substratzugabe 38 4.2 Kontrollreihe 39 4.3 Testreihen mit Mangel an Spurenelementen 45 4.4 Spurenelementkonzentration innerhalb der Reaktoren 60 4.5 Test auf Signifikanz 64 5 Modellierung des Biogasprozesses unter Berücksichtigung der Spurenelemente 70 5.1 Mathematische Beschreibung des entwickelten Modellansatzes 70 5.2 Anknüpfung an das ADM1da 77 5.3 Programmtechnische Umsetzung/Implementierung 79 5.4 Anwendung des Modells anhand einer Biogasanlage 80 5.4.1 Simulation der Biogasanlage 80 5.4.2 Monovergärung von Maissilage 84 5.4.3 Substratmix zur Vermeidung eines Mangels 88 5.5 Anwendung des Modells anhand des Laborreaktors 93 5.5.1 Vergleich der Simulations- und Messdaten der Kontrollreihe 96 5.5.2 Vergleich der Simulations- und Messdaten der Testreihe 103 6 Zusammenfassung 122 7 Literaturverzeichnis 129 8 Anhang 138 8.1 Laborergebnisse Testreihe 138 8.1.1 Biogasmenge 139 8.2 Boxplot 140 8.2.1 Mangelphase 140 8.2.2 Rückführphase 141 8.3 Massenbilanzen 141 8.4 Vergleich Simulation/Messdaten – Kontrollreihe 142 8.4.1 pH-Wert 142 8.4.2 Biogasmenge 143 8.4.3 Methangehalt 143 8.5 Vergleich Simulation/Messung Testreihe 144 8.5.1 Spurenelemente 144 8.5.2 pH-Wert 146 8.5.3 FOS/TAC Verhältnis 147 8.5.4 Biogasmenge 148 8.5.5 Methangehalt 149

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40

Patel, Jayeskumar Pravinzhai. "Characterisation study of nitrogen detection on coked hydrotreating catalyst." Thesis, Imperial College London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271715.

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41

Smith, Karon Lesley. "Remote sensing of leaf responses to leaking underground natural gas." Thesis, University of Nottingham, 2002. http://eprints.nottingham.ac.uk/12911/.

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Detection of leaking gas pipelines is important for safety, economic and environmental reasons. Remote sensing of vegetation offers the potential to identify gas leakage. The research aim was to determine the effects of elevated soil concentrations of natural gas on overlying vegetation. Pot-scale investigations were carried out to determine whether changes in spectral characteristics were specific to natural gas or were a generic response to soil-oxygen displacement. Natural gas, argon, nitrogen and waterlogging were used to displace soil-oxygen. Leaf response to soil oxygen displacement was increased reflectance in the visible wavelengths and changes in the position and shape of the red-edge, which shifted towards longer wavelengths as the control plant matured, while the red-edge of the treated plant remained stationary indicating an inhibition of maturing. The shape of the red-edge differed in bean and barley with bean exhibiting a single peak in the first derivative that moved with plant maturity; barley exhibited a peak at 704 nm with a shoulder at 722 nm that shifted to shorter wavelengths during plant stress. Argon and waterlogging exhibited a greater response than natural gas, which had been administered noncontinuously. These experiments suggest the response to natural gas was generic to soil-oxygen deficiency. Field studies were conducted to determine whether spectral changes in leaves identified in pot trials were observable in crop canopies under field conditions. Reflectance of barley growing above a leaking gas pipeline was increased in the visible wavelengths and the red-edge was at a shorter wavelength. When the majority of the crop was fully developed, the barley above the gas leak was greener, suggesting that development was inhibited by soil-oxygen displacement. It might be possible to detect leaking gas by remote sensing of vegetation in conjunction with pipeline maps, but limitations in the spatial resolution of current satellite sensors and the infrequency of cloud free skies in the UK suggest that further work is needed before an operational system could be available.

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42

Sritongkam, Pornpimol. "Electrochemical measurement of polycyclic aromatic hydrocarbons." Thesis, Cranfield University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274039.

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43

Kong, Ming-Teck. "Downstream oil products supply chain optimisation." Thesis, Imperial College London, 2002. http://hdl.handle.net/10044/1/7714.

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44

Fothergill, Catriona E. "The role of computational fluid dynamics in predicting atmospheric flow and dispersion in the petrochemical industry." Thesis, University of Surrey, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250858.

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45

Greenberg, Ariela Caren. "Fighting Bias with Statistics: Detecting Gender Differences in Responses on Items on a Preschool Science Assessment." Scholarly Repository, 2010. http://scholarlyrepository.miami.edu/oa_dissertations/665.

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Differential item functioning (DIF) and differential distractor functioning (DDF) are methods used to screen for item bias (Camilli && Shepard, 1994; Penfield, 2008). Using an applied empirical example, this mixed-methods study examined the congruency and relationship of DIF and DDF methods in screening multiple-choice items. Data for Study I were drawn from item responses of 271 female and 236 male low-income children on a preschool science assessment. Item analyses employed a common statistical approach of the Mantel-Haenszel log-odds ratio (MH-LOR) to detect DIF in dichotomously scored items (Holland & Thayer, 1988), and extended the approach to identify DDF (Penfield, 2008). Findings demonstrated that the using MH-LOR to detect DIF and DDF supported the theoretical relationship that the magnitude and form of DIF and are dependent on the DDF effects, and demonstrated the advantages of studying DIF and DDF in multiple-choice items. A total of 4 items with DIF and DDF and 5 items with only DDF were detected. Study II incorporated an item content review, an important but often overlooked and under-published step of DIF and DDF studies (Camilli & Shepard). Interviews with 25 female and 22 male low-income preschool children and an expert review helped to interpret the DIF and DDF results and their comparison, and determined that a content review process of studied items can reveal reasons for potential item bias that are often congruent with the statistical results. Patterns emerged and are discussed in detail. The quantitative and qualitative analyses were conducted in an applied framework of examining the validity of the preschool science assessment scores for evaluating science programs serving low-income children, however, the techniques can be generalized for use with measures across various disciplines of research.

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46

Hobbs, William. "Economic Impact of Rock Climbing on the Communities Surrounding the Red River Gorge, Kentucky." TopSCHOLAR®, 2002. http://digitalcommons.wku.edu/theses/665.

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The sport of rock climbing has exploded in America over the last decade resulting in millions of climbers flocking to the available areas near and far from their home. Such traffic demands clear and effective policy-making from land managers, public and private, in order to conserve and protect valuable natural resources. The Red River Gorge area hosts thousands of climbers each year and contains over 1,000 climbing routes in ten separate areas with an array of amenities for lodging, food, and other recreation. However, no research has been completed to determine the benefits of these climbing resources for local businesses and residents. This study was designed to investigate the economic impact of rock climbers on the local communities in and around the Red River Gorge area. Surveys obtained from 141 climbing groups over fifty-one days provided travel distances, group size, trip duration, and the amount of expenditure inside and outside the Gorge area. Climbers surveyed spent $34,708.45 in Kentucky, an average of $28.17 per climber per day. Specifically within the delineated Gorge area, the expenditure totaled $25,563.50, or $19.95 per climber per day. The data were analyzed using the input-output model, IMP LAN, to determine the impact on employee compensation, labor income, total value added, and employment in the designated area. The total economic effect inside the Gorge area, based on $1 million in annual climber expenditure, was $307,318.

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Merry, Adam M. "More Than a Bath: An Examination of Japanese Bathing Culture." Scholarship @ Claremont, 2013. http://scholarship.claremont.edu/cmc_theses/665.

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Steeped in tradition for over a thousand years, bathing culture in Japan remains relevant due to the preservation of the traditional, innovative modernization of existing bathing structures, and the diversification therein. This thesis will examine the significance of bathing culture, focusing largely on onsen and sento, account for its historical evolution, analyze how it functions in modern society and forecast its future viability. More specifically, the concept that Japan's vibrant bathing culture was able to flourish due to mythological creation stories, politically motivated access to baths, propagated therapeutic value, and scientific reinforcement of the benefits of a hot bath will be explored.

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48

Nemati, Farshad, and University of Lethbridge Faculty of Arts and Science. "Contribution of brain with or without visual cortex lesion to exploratory locomotion in the rat." Thesis, Arts and Science, 2008. http://hdl.handle.net/10133/665.

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Over the past five decades spatial behavior has been a subject of research interest in psychology and neuroscience, in part based on philosophical theories of mental spatial representations. In order to continue uncovering the facts regarding spatial behavior, the focus of this thesis was on the contribution of entry point and visual inputs to the organization of exploratory locomotion and spatial representation in the rat. Despite the contribution of the hippocampus to spatial abilities, the exploratory locomotion is still visually organized in rats with damage to the hippocampus. On the other hand, recent studies have demonstrated a contribution of visual areas to the spatial ability of the rat. Nevertheless, the contribution of visual cortex to the organization of exploratory locomotion has not been studied in an open field. The experiments in this thesis were designed to characterize the organization of exploratory locomotion to the point of entry and/or visual cues. Rats were started from the edge or center of an open table near or on which a salient object could be placed. The main findings were that rats organized their exploratory locomotion to their point of entry and modified their behavior as they encountered objects. Also, rats with damage to visual cortex displayed an extra-attachment to the visual objects and in contrast to controls did not expand their exploratory locomotion with time. The results are discussed with respect to the centrality of the entry point in the organization of exploratory locomotion and the neural network that control visual exploration in the rat.
xiii, 220 leaves : ill. ; 29 cm. --

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49

Amorós, Torrent Jaume. "Grup fonamental de les varietats de Kähler, El." Doctoral thesis, Universitat de Barcelona, 1997. http://hdl.handle.net/10803/665.

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Estudiem el grup fonamental de varietat algebràïques complexes i la seva monodromia. Les línies d'estudi són:

- L'àlgebra de Malcev dels grups fonamentals de varietats compactes Kahler: Provem que no pot ser lliure, i donem una cota inferior del nombre de relacions cas que la varietat sigui no fibrada. La determinem quan la dimensió de Kodaira és igual a un.

- Pinzells de Lefschetz de corbes: obtenim fòrmules per a la monodromia geomètrica i el grup fonamental per a pinzells de Lefschetz de corbes sobre la recta projectiva, amb ella demostrem un resultat de formalitat topològica de famílies de corbes, a l'igual que propietats conegudes d'entropia i quasi unipotència d'aquestes famílies.

- La connexió de Gauss-Manin en el grup fonamental:

Construïm complexos de Dolbeault logarítmics relatius analítics reals per a famíliers de varietats projectives, amb connexió de Gauss-Manin. Calculem la realització de la Rham d'aquesta coneexió en el grup fonamental de famílies de corbes afins racionals i no racionals, obtenint un contrast notable.

Caracteritzem els grups de Galois diferencials de la connexió de Gauus-Manin en el grup fonamental com a extensions unipotents dels seus anàlegs cohomològics.
Estudiamos el grupo fundamental de variedades algebraicas complejas y su monodromía. Las líneas de estudio son:

- El álgebra de Malcev de los grupos fundamentales de variedades compactas Kahler: Probamos que no puede ser libre, y damos una cota inferior del número de relaciones en el caso en que la variedad sea no fibrada. La determinamos cuando la dimensión de Kodaira es uno.

- Pinceles de Lefschetz de curvas: obtenemos fórmulas para la monodromía geométrica y en el grupo fundamental para pinceles de Lefschetz de curvas sobre la recta proyectiva, con ella demostramos un resultado de formalidad topológica de familias de curvas, así como propiedades conocidas de entropía y cuasi unipotencia de estas familias.

- La conexión de Gauss-Manin en el grupo fundamental:

Construimos complejos de Dolbeault logarítmicos relativos analíticos reales para familias de variedades proyectivas, con conexión de Gauss-Manin. Calculamos la realización de la Rham de esta conexión en el grupo fundamental de familias de curvas afines racionales y no racionales, obteniendo un notable contraste.

Caracterizamos los grupos de Galois diferenciales de la conexión de Gauss-Manin en el grupo fundamental como extensiones unipotentes de sus análogos cohomológicos.

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50

Anderson, Michael. "Journeys in Teacher Professional Development: Narratives of Four Drama Educators." University of Sydney. Policy and Practice, 2002. http://hdl.handle.net/2123/665.

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Ongoing teacher professional development is an essential part of the wellbeing of the schooling system and successful outcomes for students. In the past, teacher professional development has been used to describe an often �top-down� method of training to meet systemic needs while taking little account of teacher's individual needs. This approach often conceptualises the teacher's life as a dichotomy with the personal and the private separated and unrelated. In contrast, teacher professional development in this study is conceptualised as a journey that includes encouraging and discouraging turns. The journey is explored through the experiences of two primary and two secondary drama educators using Hargreaves and Fullan's (1992) organisers: teacher development as knowledge and skill development; teacher development as self understanding and teacher development as ecological change. The study focussed specifically on teachers of drama. Of the four educators two were beginning teachers, one primary and one secondary and two were experienced teachers, one primary and one secondary. The teachers were interviewed over twelve months. Narrative vignettes were developed from the interviews. As the context for these teacher journeys was pivotal, the influences on the teaching of drama in New South Wales were investigated. This included an exploration of the major issues that have influenced the development of drama education both internationally and in Australia. The concluding reflections from this study suggest that there is strong interaction between teachers' personal and professional lives. Teachers' personal circumstances, family histories and schooling backgrounds all have an important influence on their work as teachers. Significantly, issues related to drama education's history and current context reflected these teachers' classroom realities. The teachers argue that they understand their professional development needs best and should have influence and ownership of their own professional development experiences. They found aspects of their tertiary training and teacher induction unsatisfactory. The two beginning teachers in this study struggled to survive the difficulties of their first year and both seriously considered leaving teaching. The teachers describe self understanding through distinct phases of development that are made unique by each teacher's personality and context. The teachers saw subject identity and pedagogy as important to their professional identity. They report that times of crisis often lead to positive changes in their professional development journeys. The ecology for these teachers was made up of several complex issues that are resistant to change and there were a number of impediments reported by the teachers that arise from their teaching ecologies. Two of the teachers have used a change of context to improve their satisfaction and confidence levels. Two teachers described beneficial experiences with supervisors in the school setting. If beneficial ecological change is to occur, education systems must attend to the needs of teachers and provide opportunities to teach unimpeded by systemic obstacles. The study calls for changes in professional development and for the recognition of the multilayered nature of the teachers' journey. The study calls for a reconceptualisation of teacher professional development that recognises each teacher's ecology and self understanding. The renewed impetus for arts education will only be successful if the complexity of the teachers' journey is recognised and systemic obstacles are removed.

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