Solar energy is an important form of renewable energy that can be used as an alternative to fossil fuels. It can be used to produce electricity or to provide heat. One particular application is using solar energy for a domestic hot water system. The purpose of this research is to improve the thermal performance of a solar domestic hot water (SDHW) system. Experimental research was conducted to study the thermal performance of a shell-and-3coil heat exchanger and a shell-and-4coil heat exchanger using either water or glycol as working fluids on the tube side. An experimental set-up simulating a SDHW system was designed and constructed. The set-up contained a 270 L storage tank, a shell-and-three coil heat exchanger or a shell-and-four coil heat exchanger, and electrical heaters to simulate the solar collector. At the inlets and outlets of the storage tank and the heat exchanger the temperatures, pressures, and flow rates were measured to determine the thermal performance. The results from the experiment tests were analyzed in terms of the overall heat transfer coefficient product (UA) and the pressure drop (?P) between the inlet and outlet of the heat exchanger. The UA value of the shell-and-4coil heat exchanger was higher than the UA value of the shell-and-3coil heat exchanger. For example, at a heat transfer rate of 2000 W for water, the UA values were 240 W/K and 270 W/K for the shell-and-3coil heat exchanger and the shell-and-4coil heat exchanger, respectively. With respect to glycol, at a heat transfer rate of 2000 W the UA values were 197 W/K and 215 W/K for shell-and-3coil, and shell-and-4coil heat exchanger, respectively. The degradation of the thermal performance of the shell-and-3coil was offset by benefits, such as reduction in mass, volume, labor cost and the final cost. A reasonable agreement between theoretical and experimental results in terms of the UA value was observed. The thermal performance of each coil in both heat exchangers was below that predicted by the relevant heat transfer correlations. A performance factor was calculated for each coil. For both glycol and water, and both heat exchangers, the performance factors for the inner most and outer most coils were 0.70 and 0.53, respectively. However, there is a slight difference in the performance factors of coils between the inner most and the outer most coils for the 3-coil and 4-coil heat exchangers. For these coils the performance factors varied from 0.55 to 0.67.

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In this dissertation, I examine trajectories of cultural evolution among complexhunter-gatherers and middle range societies. Broadly, I consider the theoretical issuesrelated to these two areas of study and how we should conceptualize the study of socioculturalevolution in societies organized at this scale. I apply these ideas to the study ofthe prehistoric hunter-gatherers who occupied Sapelo Island, Georgia, U. S. A.Specifically, I examine the Archaic period (4200 – 3000 B. P.) occupation of the SapeloShell Ring complex, located on the western side of the island. In particular, I study issuesof sedentism, settlement aggregation, mound construction, and the emergence of socialinequality as they relate to shell rings in the southeastern United States, as well as otherareas of the world. One of the central problems for studying these sites is whether shellrings form by gradual accumulation or by intentional construction and the concomitantsocial formations associated with these two different behaviors. Using geophysicalsurvey, artifact distributions, and radiocarbon dating, I examine the use and nature ofspace at the site as well as site formation processes. I present the results of both thegrowth band analysis on clams and the isotopic analysis on clams and oysters from thesite in order to address season of occupation. In addition to this new data, a reanalysis ofprevious excavations is presented. Combined, these data lend important insights intodifferent dimensions of socio-political complexity. Specifically, these data suggest thatthe Sapelo Shell Ring complex population was relatively large for its time. It addition, itseems that at least some portion of the population occupied the site year-round. Despiteit large population size and reduced mobility the occupants of the site maintained at leastsome degree of egalitarian social relations.

Public memory of psychological casualties from the Great War and the Second World War has recalled men who were shunned and scorned by society and their peers. Using letters and diaries written contemporaneously within the two World Wars, and newspapers and official documents from the inter-war period, this paper examines the attitudes of Second World War New Zealand soldiers to those in their midst who were mentally injured by their experiences and unable to continue their duties. This research indicates that there was more compassion and sympathy from government agencies, the public and comrades of shell shock and anxiety neurosis victims, than has been indicated in existing historiography. The onset of shell shock during the Great War of 1914 to 1918, and how it entered the public sphere, influenced the attitudes of the men who, a generation later, were again going into battle. Social changes in New Zealand, both before and during the Second World War, are investigated to determine how they influenced the attitudes of the men of the Second New Zealand Expeditionary Force during World War Two in comparison to those of the New Zealand Expeditionary Force of the Great War.

Granular Activated Carbon (GAC) is used in packed beds to treat trace quantities of icropollutants. Many years of research and industrial use has ensured that it is highly effective as a water treatment process. However, GAC is expensive and economic considerations mean it has to be recovered and re-used Powdered Activated Carbon (PAC; is a cheaper alternative but the particle size range means it is unsuitable for packed bed applications. This thesis describes a novel method for utilising PAC to treat micropollutants. By contacting carbon paracles with air bubbles, under conditions o.lrotational shear and a binding agent, oleyl alcohol, carbon-coated air bubbles form which remain stable while agitated byflowing water. A stabilised air bubble can be visualised as a phere with an impervious core (the air bubble), surrounded by a thin layer of porous matehal (PAC). Theory dictates that all these stabilised air bubbles can be moved counter-currently to a contaminated stream, higher throughputs than conventional packed beds are possible. Several aspects of this process are investigated. Bubble generation is critical and so the literature was reviewed to explain the mechanisms involved Practical use was made of this knowledge in designing a larger bubble generator. Transferring the coated-bubbles to a contacting column was difficult. Problems associated with the various methods employed are described and recommendations are made for improvement. The contacting column was used to assess the stability and adsorptive capacity of the bubbles. The possibility of counter-current flow using stabilised air bubbles was also evaluated and found to be incompatible with the current column design. The stabilised bubbles collected in the column resembled an inverted fluidised bed. Experiments were performed to test Richardson and Zaki's hydrodynamic laws for conventional fluidised beds were applicable to inverted beds. The adsorptive capacity of the bubbles was assessed by dosing the water with trace levels of phenol and p-chlorophenol. Samples taken from before and after the fluidised bed were analysed and compared. The results were inconclusive, although the concentration profile produced indicated that flow through the bubble bed was piston-flow.

With an increasing demand for alternative clean energy solutions, much effort is being invested in the progression of nanoscale semiconductor materials in hopes of better harnessing solar energy. ZnO and TiO2 remain the most prominent photocatalytically active materials. This thesis reports on a comparison between nanoscale core-shell and hierarchical Zn-Ti-O/ZnO heterostructures. After a seed layer thickness optimization, hydrothermally grown ZnO nanorods were coated with mixed concentrations of Ti and Zn within an oxygen rich sputtering environment at two distinct temperature zones. Core-shell structures resulted from low temperature (23°C) depositions while hierarchical branch structures grew at high temperature (800°C). Excluding deposition temperature and the strategic variation of Zn and Ti gun power, every fabrication process remained identical between the two resultant heterostructure groups. Amongst the variety of samples produced, one from each heterostructure group proved notably similar in structural dimension, composition, and crystallization, yet demonstrated distinct differences in photoluminescence and dye degradation via UV-visible light spectroscopy. While photoluminescence results indicated core-shell heterostructure more photocatalytically promising, hierarchical heterostructure prevailed as the more powerful photocatalyst. Increased surface area due to hierarchical branching in conjunction with enhanced light exposure was believed responsible for the improved photocatalytic effectiveness.

The aim of this thesis is to describe how the company Royal Dutch Shell plc takes care of its brand and find out what image of the Shell brand has in the Czech Republic. The thesis is divided into theoretical and practical part. In the theoretical part I deal with the process of brand management. I describe here brand equity and its building, brand strategies, brand valuation. Onwards I describe brand research with an emphasis on the semantic differential. Semantic differential is a method of qualitative research used in the practical part of this thesis. In the practical part I deal with the activities and history of the company Royal Dutch Shell plc and the company Shell Czech Republic a.s. This part also contains research of the Shell brand, which forms the key part of this thesis. Based on this research, I find out image of the Shell brand and I compare it with a competitive brand OMV.

The M-shell x-ray production cross section for thorium and uranium have been determined for protons of energy 0.4 - 4.0 MeV, helium ions of energy 0.4 - 6.0 MeV, carbon ions of energy 4.5 - 11.3 MeV and oxygen ions of energy 4.5 - 13.5 MeV. The total cross sections and the cross sections for individual x-ray peaks in the spectrum, consisting of the following transitions Mz (M4-N2, M5-N3, M4-N3), Ma (M5-N6,7), Mb (M4-N6, M5-O3, M4- O2), and Mg (M4-O3, M5-P3, M3-N4, M3-N5), were compared to the theoretical values determined from the PWBA + OBKN and ECUSAR. The theoretical values for the carbon and oxygen ions were also modified to take into account the effects of multiple ionizations of the target atom by the heavier ions. It is shown that the results of the ECUSAR theory tend to provide better agreement with the experimental data.