The goal of this study was to assess the effect of residence time on the chemical and microbial quality of reclaimed water in two distribution systems located in southern Arizona. Utility A produced Class A water and utilized chlorine as a means of disinfection whereas Utility B produced Class A+ water and utilized UV radiation as a means of disinfection. Water-based pathogens were consistently detected in both distribution systems beyond the point of compliance, while microbial indicators like Escherichia coli was only detected in Utility B suggesting that treatment eliminated waterborne pathogens. Heterotrophic plate concentrations in samples from both utilities initially increased rapidly with increased distance from the point-of-compliance and were as high as 10⁹ CFU/100ml. Regardless of the initial level of treatment, the microbial quality deteriorated with increased residence time in the distribution systems. The second study was designed to evaluate the effect of reclaimed water storage on microbial and chemical quality of two classes of reclaimed water (Class A and Class A+). In Class A water, nitrification was observed during both field scale trials resulting in concentrations greater than 10mg/L while nitrification was not observed in Class A+. Chlorine residuals rapidly decreased within 48hours of storage. HPC concentration were as high as 10⁷ - 10⁸ /100ml. In both field scale trials, there was no observed growth of HPC during storage and waterborne indicator bacteria were rarely detected, and if detected, only at low concentrations. Based on this data, deterioration of microbial water quality during storage is minimal.

This thesis describes, in a manufacturing context, the development of new waterbased core technology for light alloys. Cores used for steel casting are made from fused silica and are removed using hot sodium hydroxide under refluxing (pressurising hot acids). However, aluminium and other light alloys are attacked by sodium hydroxide. Currently there is no good core system for aluminium and other light alloys. It is therefore desirable to find an alternative material/leaching agent combination for casting aluminium and other light alloys. The recent research review has shown that ceramic cores are mostly made by fused silica with different additives. The previous research has suggested using fused silica (different mesh size) as filling material and using magnesium oxide to control the slurry working life of core mixes. Calcium silicate assists core leaching in dilute acid. The plaster (calcium sulphate) in the form of proprietary plasters (Crystcal R, Fine Casting Plaster) is used to create bond and gives strength to the core. Lithium carbonate acts has an accelerator, improving the strengthening effect of the plaster in the cores. The binder (Ludox® AM) and water act (as added materials) to bind the composition Core compositions were made with different core trials to produce a core, which records suitable strength and quick leaching properties for light alloys. Core trials were individually mixed and poured into a wooden core box. Cores were pre-dried for twenty-four hours. Cores were fired to different temperatures for two hours, followed by two hours cooling. The cores were subjected to computerised three-point bend test to record the Modulus of rupture (MOR). The plain strain fracture toughness and Weibull parameters were calculated. The Weibull parameter was plotted using Minitab analysis software. Using the cores, gravity die casting process were carried out. The subsequent castings was dipped in diluted nitric, citric and acetic acid to leach out the core. Using different core compositions, core trials were mixed, poured, dried, tested and leached. The high amount of plaster in core trials records high MOR when cores were fired between 200°- 400° C and the opposite result when fired between 600°- 800° C. The different grade of plasters(CRP,FCP) do not influence the strength. One percent of magnesium oxide gives a very short working life. High amount of binder(Ludox® AM) in core produce strong cores. Workable MOR results can be obtained depending on composition allowing manual handling or a waxing process. The fracture toughness is typical of a brittle material, with matching Weibull parameters. The casting process suggests that the new materials are sufficiently refractory. The cores are leached out using diluted nitric, acetic and citric acid at rates compatible with commercial manufacture. This methodology has successfully produced a core using fused silica with plaster and magnesium oxide for aluminium and possibly for light alloys. Different core trials can be used depending on the specific industrial application relating to strength and removal with acid attacking the metal. Further work is needed to fine tune optimum leaching conditions.

Planning and managing outdoor recreational resources at larger spatial scales, conceptualized as a regional approach to recreation planning and management, is studied. Considering and understanding the role of spatial scale has been beneficial to the field of ecology; however, the importance of spatial scale has rarely been considered in the recreation resource management literature. A regional approach to planning and management is differentiated from a site-specific approach as managers and planners must consider the implications of management actions or policies at a larger spatial scale than a single park, recreation area, lake, or reservoir. For this study, the provision of boating opportunities at Utah lakes and reservoirs is considered. Multiple data collection techniques, both quantitative and qualitative, were applied in this study. Additionally, two distinct groups of respondents participated: (1) park managers and their staff; and (2) boaters (individuals who own boats registered in Utah). Data were collected at three different spatial scales: (1) lake or reservoir level (site); regional level; and (3) state level. Multiple analytical approaches were used to ascertain both groups' perspectives towards a variety of topics important to recreation management including content analysis and cluster analysis, as well as considering experience use history. The results suggest implementing a regional approach is more complicated and inclusive than providing a wide range of recreational opportunities. The organizational capacity of the managing agencies, along with their ability to cooperate with other governmental and private organizations, is also important. Also, considering larger spatial scales increases an agency's options to address various challenges such as conflict, displacement, recreation succession, and homogenization and sub-optimization. As such, when prescriptive decisions about where various recreational opportunities ought to be provided, management problems and issues and agency capacity should also be considered. This dissertation also provides a model for conducting regional analyses.

In recent years, the impact of humans on the environment has been the subject of much debate. Car companies in particular are among the main actors in this environmental degradation with the polluting aspect of combustion cars. However, in recent years, these companies have started to switch to electric cars in order to reduce their impact on the environment. This is the case for Volvo, for example, where electrification is a priority. With the goal of becoming a climate neutral company by 2040, Volvo is driving innovation to reduce the use of polluting materials, such as oil.  Oil is not only used to power cars, but also in the fluids used to cool electrical machines or lubricate transmissions. However, alternatives to these fluids have emerged in recent years, such as glycerol-based or water-based lubricants. This Master Thesis aims to follow the evolution of water-based lubricants, but also to compare the performance of existing fluids within electric drivelines.  Water is known to have very good thermal properties but also to have a high electrical conductivity, which represents a big challenge for the use of this type of lubricant within an electric machine. It is with the aim of evaluating the impact of these properties that the following study investigates the electrical compatibility of a water-based lubricant within an electrical machine. The thermal performance of this type of fluid is also investigated and compared to that of an oil- based fluid also studied at Volvo. This master thesis will serve as a springboard for further studies of these lubricants, and will also raise questions and challenges that need to be addressed in the future in order to be able to take full advantage of the properties of these water-based lubricants.

Pesquisas sobre diferentes modelos de treinamento no meio aquático já demonstraram seus efeitos benéficos em diferentes capacidades físicas, bem como para a população com doenças metabólicas. Entretanto, para sujeitos portadores de síndrome metabólica (SM) são escassos os estudos que investigaram qual modelo de treinamento no meio aquático poderia gerar melhoras físicas e metabólicas. Assim, o objetivo do presente estudo foi comparar os efeitos neuromusculares e metabólicos de 12 semanas de treinamento aeróbio, treinamento de força e treinamento combinado no meio aquático em mulheres com SM. Foram selecionadas 51 mulheres, pós-menopáusicas, sedentárias e portadoras de SM que foram randomicamente divididas em três grupos de intervenção: hidro-aeróbica (HA; n=18; 63,77±5,03 anos), hidro-força (HF; n=16; 61,01±4,93 anos) e hidro-combinada (HC; n=17; 60,52±6,91). Uma sub-amostra participou de oito semanas sem prática de exercício físico para caracterizar um período controle. Os três grupos de intervenção realizaram duas sessões semanais de 60 minutos durante 12 semanas. Antes e após o período de treinamento foram realizadas análises sanguíneas, testes de força muscular, testes funcionais e questionário de qualidade de vida Para análise estatística foi utilizada o modelo de Equações de Estimativas Generalizadas (GEE) com post hoc de Bonferroni (α = 0,05). No período controle, nenhuma das variáveis avaliadas apresentou alteração significativa (p>0,05). Após o período de intervenção houve uma redução significativa da glicemia de jejum (HA: -7,6%; HF: -14,4%: HC: -14,0%), da pressão arterial sistólica (HA: -2,9%; HF: -8,5%: HC: -4,0%) e na contagem total dos fatores da SM (HA: -1,7%; HF: -6,7%: HC: -8,7%) sem diferença entre os grupos. Para a força muscular, houve um aumento significativo na força muscular dinâmica máxima de extensores de joelho (EJ) (HA: 29,6%; HF: 14,6%: HC: 26,7%) e flexores de cotovelo (FC) (HA: -0,1%; HF: 3,1%: HC: 7,4%), para a força resistente de EJ (HA: 25,2%; HF: 18,9%: HC: 23,8%) e FC (HA: 24,3%; HF: 16,6%: HC: 27,8%), para a contração isométrica voluntária máxima de EJ (HA: 11,0%; HF: 8,4%: HC: 26,4%), sem diferença entre os grupos de treinamento Para a atividade eletromiográfica (EMG) do reto femoral (RF) houve um aumento significativo apenas para o grupo HA (35,3%). A EMG de vasto lateral (VL) apresentou efeito significativo ao longo do tempo sem diferença entre os grupos (HA: 33,2%; HF: 40,4%: HC: 52,6%). Os testes funcionais apresentaram melhora significativa ao longo do tempo: Sentar e levantar (HA: 34,8%; HF: 29,0%: HC: 25,1%), Time-up-and-go (HA: -13,5%; HF: -11,8%: HC: -13,7%) sem diferença entre os grupos. A qualidade de vida apresentou aumento significativo no domínio físico (HA: 3,66%; HF: 3,88%: HC: 3,81%) sem diferença entre os grupos. Dessa forma, conclui-se que não houve diferenças expressivas entre os modelos de treinamento aeróbio, de força muscular ou combinado nas variáveis analisadas. Todos os treinamentos de hidroginástica foram eficientes para diminuir fatores da síndrome metabólica como a glicemia de jejum e a pressão arterial e para aumentar a força muscular dinâmica máxima, a força resistente e a força isométrica. Além disso, os treinamentos melhoraram a qualidade de vida e a capacidade funcional das mulheres. / Research about different training models in the aquatic environment has already demonstrated its beneficial effects on different physical capacities as well as for the population with metabolic diseases. However, for subjects with metabolic syndrome (MS) there are few studies that investigated which training model in the aquatic environment could generate physical and metabolic improvements. Thus, the aim of the present study was to compare the neuromuscular and metabolic effects of 12 weeks of aerobic training, strength training and combined training in the aquatic environment in women with MS. Fifty-one women, postmenopausal, sedentary and SM carriers were randomly divided into three intervention groups: hydro-aerobic (HA, n = 18, 63.77 ± 5.03 years), hydro-power (HP; N = 16, 61.01 ± 4.93 years) and hydro-combined (HC; n = 17; 60.52 ± 6.91). A subsample participated in eight weeks without physical exercise to characterize a control period. The three intervention groups performed two weekly sessions of 60 minutes for 12 weeks. Before and after the training period, blood tests, muscle strength tests, functional tests and a quality of life questionnaire were performed For statistical analysis, the Generalized Estimates Equations (GEE) model with Bonferroni post hoc (α = 0.05) was used. In the control period, none of the evaluated variables presented significant alteration (p> 0.005). After the intervention period there was a significant reduction of fasting blood glucose (HA: -7.6%, HP: -14.4%: HC: -14.0%), systolic blood pressure (HA: -2.9 HP: -8.5%: HC: -4.0%) and in the total counting of the factors of the SM (HA: -1.7%, HP: -6.7%: HC: -8.7% ) without difference between groups. For muscle strength, there was a significant increase in maximal dynamic muscle strength of knee extensors (KE) (HA: 29.6%, HP: 14.6%: HC: 26.7%) and elbow flexors (EF) (HA: -0.1%, HP: 3.1%: HC: 7.4%), for maximal repetitions of KE (HA: 25.2%, HP: 18.9%: H: 23.8% ) and EF (24.3%; HF: 16.6%: HC: 27.8%), for the maximum voluntary contraction of KE (HA: 11.0%, HP: 8.4% 26.4%), without difference between the training groups. For the electromyographic (EMG) activity of the rectus femoris (RF) there was a significant increase only for the HA group (35.3%). The vastus lateralis (LV) EMG showed significant effect over time with no difference between the groups (HA: 33.2%, HP: 40.4%: HC: 52.6%) The functional tests showed significant improvement over time: sitting and lifting (HA: 34.8%, HP: 29.0%: HC: 25.1%), Time-up-and-go (HA: 5%, HP: -11.8%: HC: -13.7%) without difference between groups. The quality of life showed a significant increase in the physical domain (HA: 3.66%, HP: 3.88%: HC: 3.81%) without difference between the groups. Thus, it was concluded that there were no significant differences between the aerobic training, muscle strength or combined models in the analyzed variables. All water-based training was efficient to decrease metabolic syndrome factors such as fasting blood glucose and blood pressure and to increase maximal dynamic muscle strength, endurance strength and isometric strength. In addition, training improved the quality of life and functional capacity of women.

Modern day oil & gas well costs are driven by drilling performance as time becomes the dominant capital expense source. The ability to lower drilling costs becomes paramount when tight economic margins and high uncertainties/risk exist. Penetration rate decreases drastically in ultra deep formations, and substantial time is spent drilling the deepest section of these wells. Therefore, significant cost savings may be obtained through an improvement in penetration rate in deep formations. This paper shows that in HTHP (High Temperature High Pressure) hard shale/sand environments that PDC (Polycrystalline Diamond Compact) bits paired with water based mud experience 88% improvement in penetration rate than those paired with oil based mud. With this improvement in drilling rate, well costs can be substantially reduced making future ultra-deep hydrocarbon accumulations economically producible. Also observed was a drastic decrease in penetration rate in PDC bits with oil base mud which led to the use of diamond impreg bits, as the water base with PDC still maintained respectable penetration rates. The conventional penetration rate controls are still applicable in this case, but there exists a fundamental difference between the rock/fluid interactions of each mud type. Bit type, operating conditions, formation characteristics, and bit hydraulics are shown to not be the dominant influencing factor of this performance trend. The water base fluids examined have higher filtrate rates than the oil base fluids. However, a consistent data set of increasing filtrate rate corresponding to increasing penetration rate cannot be derived. Therefore filtration characteristics remain as a possible and partial influencing factor behind this data. Future experimental research is needed to confirm or disprove this theory. At this time the actual cause of this behavior is unknown, however the trend has been established showing water base drilling fluids performance versus oil base in the HTHP/hard rock environment.

This paper adopts a geographical perspective to understand the conceptual and theoretical issues of resort morphology. Resort morphology refers to “the forms and associated functions of a destination area and their development”. Resort towns are differentiated from other urban areas in terms of morphology because of their functional emphasis on tourism. The literature reflects the significant interest of European geographers in the morphological study of coastal resort towns. However, limited attention has been given to resort morphology in developing countries. It is argued that the complex of contextual factors that influence the morphological character of resorts needs to be considered and, furthermore, there is a great need to develop a systematic approach for investigating resort morphology. Based on a review of literature, this paper first introduces the contributions and implications of related research to the understanding of resort morphology: study of resort evolution, the Recreational Business District, urban morphology, and Geographic Information System (GIS) applications. Then, the situation of China is addressed because there is a striking contrast between the rate of change and increasing complexity of Chinese resorts and the very limited amount of studies from either western or Chinese scholars. A quantitative-qualitative mixed research approach is introduced to understand transitional resort morphology in China. It involves classifying land uses, building a descriptive and explanatory framework, creating form-function maps, and the analysis of morphological characteristics. Two study areas are selected for detailed examination: a coastal resort town, Sanya and a lake-based resort town, Wuxi. Morphological changes associated with key contextual factors influencing tourism and recreational development are analyzed in these places. A comparative discussion of Sanya and Wuxi indicates similarities between their development patterns of resort morphology and their present morphological features but significant differences in terms of history, evolutionary process, tourism resources, location and level of economic development. It is less helpful simply to define models applicable to distinct Chinese water-based resort towns than to identify similarities among them. Rules for resort study in the Chinese context are recommended and the characteristics of morphological transformation in a typical water-based resort town are summarized in view of resort development patterns. It is indicated that the morphology of a typical water-based resort cluster can be in large part a function of its recreational hinterlands (urban areas), and whether it is well-planned or more naturally developed. Finally, the relationships between contextual factors, tourism development, and resort evolution and resort morphology are interpreted in the context of Chinese water-based resort towns. The significance of morphological research on current as well as past resort structure for future planning and conservation activities is indicated. A systematic approach, which combines the morphological method, the functional method and the evolutionary method, is suggested to study resort morphology. By using resort evolution theory, it is indicated that resort morphology can be clearly identified and explored within a conceptual framework. This study also shows that GIS techniques are highly applicable in the study of resort morphology. This study indicates that water-based resort morphology in China is presently characterized by intensive land use and dense development, fast settlement expansion associated with growing vacation property development, and a generally clustered pattern of accommodation. Tourism planning in China has developed procedures and strategies with little consideration for the historical process. Therefore, this study has implications for making reasonable development strategies and efficiently implemented policies and plans. Academically, resort morphology is clarified in both Chinese and Western contexts. Also, common characteristics of Chinese water-based resort towns are summarized and phenomena generated from western studies are tested in the Chinese cases.

This paper adopts a geographical perspective to understand the conceptual and theoretical issues of resort morphology. Resort morphology refers to “the forms and associated functions of a destination area and their development”. Resort towns are differentiated from other urban areas in terms of morphology because of their functional emphasis on tourism. The literature reflects the significant interest of European geographers in the morphological study of coastal resort towns. However, limited attention has been given to resort morphology in developing countries. It is argued that the complex of contextual factors that influence the morphological character of resorts needs to be considered and, furthermore, there is a great need to develop a systematic approach for investigating resort morphology. Based on a review of literature, this paper first introduces the contributions and implications of related research to the understanding of resort morphology: study of resort evolution, the Recreational Business District, urban morphology, and Geographic Information System (GIS) applications. Then, the situation of China is addressed because there is a striking contrast between the rate of change and increasing complexity of Chinese resorts and the very limited amount of studies from either western or Chinese scholars. A quantitative-qualitative mixed research approach is introduced to understand transitional resort morphology in China. It involves classifying land uses, building a descriptive and explanatory framework, creating form-function maps, and the analysis of morphological characteristics. Two study areas are selected for detailed examination: a coastal resort town, Sanya and a lake-based resort town, Wuxi. Morphological changes associated with key contextual factors influencing tourism and recreational development are analyzed in these places. A comparative discussion of Sanya and Wuxi indicates similarities between their development patterns of resort morphology and their present morphological features but significant differences in terms of history, evolutionary process, tourism resources, location and level of economic development. It is less helpful simply to define models applicable to distinct Chinese water-based resort towns than to identify similarities among them. Rules for resort study in the Chinese context are recommended and the characteristics of morphological transformation in a typical water-based resort town are summarized in view of resort development patterns. It is indicated that the morphology of a typical water-based resort cluster can be in large part a function of its recreational hinterlands (urban areas), and whether it is well-planned or more naturally developed. Finally, the relationships between contextual factors, tourism development, and resort evolution and resort morphology are interpreted in the context of Chinese water-based resort towns. The significance of morphological research on current as well as past resort structure for future planning and conservation activities is indicated. A systematic approach, which combines the morphological method, the functional method and the evolutionary method, is suggested to study resort morphology. By using resort evolution theory, it is indicated that resort morphology can be clearly identified and explored within a conceptual framework. This study also shows that GIS techniques are highly applicable in the study of resort morphology. This study indicates that water-based resort morphology in China is presently characterized by intensive land use and dense development, fast settlement expansion associated with growing vacation property development, and a generally clustered pattern of accommodation. Tourism planning in China has developed procedures and strategies with little consideration for the historical process. Therefore, this study has implications for making reasonable development strategies and efficiently implemented policies and plans. Academically, resort morphology is clarified in both Chinese and Western contexts. Also, common characteristics of Chinese water-based resort towns are summarized and phenomena generated from western studies are tested in the Chinese cases.

The polymer-clay nanocomposites, when applied as coating materials, are expected to improve the barrier properties without sacrificing mechanical and thermal properties, and thus solve one of the most challenging problems existing in current food and beverage packaging using paper barrier coating. Furthermore, a stable polymer composite suspension in an aqueous form has many other advantages such as better environmental concern, easier manipulation and better energy saving. However, the research in this area is quite limited in the literature. In this research, a stable water-based suspension of polymer-encapsulated nanoclay composite has been successfully synthesized. The polymer nanocomposites, which encapsulate the exfoliated and well-dispersed nanoclay inside the polymer matrix, can dramatically improve almost all the aspects of mechanical properties and thermal stability in comparison with that of pure polystyrene (PS) and polystyrene butyl acrylate (PSBA) films. The particle size of nanoclay and the surface modification method are two important factors for emulsion stability, the encapsulation and intercalation (or exfoliated) degree of nanoclay. Furthermore, the impact of nanoclay on miniemulsion kinetics has been extensively investigated and the results show the hindrance of nanoclay on styrene miniemulsion polymerization kinetics.

Filter cake characterization is very important in drilling and completion operations. Heterogeneity of the filter cake plays a key role in the design of chemical treatments needed to remove the filter cake. The objectives of this study are to characterize the filter cake under static and dynamic conditions, evaluate the using of polylactic acid and chelating agents to remove calcium carbonate-based filter cake, assess glycolic acid to remove Mn3O4-based filter cake, and evaluate ilmenite as a weighting material for water-based drilling fluid. In order to characterize the filter cake, computer tomography (CT) was used in combination with the scanning electronic microscopy (SEM) to analyze the filter cake. A modified HPHT filter cell was developed to perform the filtration tests. A see-through-cell was used to check the compatibility of different chemicals that were used to remove the filter cake. The results obtained from the CT scan showed that the filter cake was heterogeneous and contained two layers with different properties under static and dynamic conditions. Under static conditions, the formation of filter cake changed from compression to buildup; while under dynamic conditions, the filter cake was formed under continuous buildup. Polylactic acid was used as a component of the drilling fluid components and the results obtained showed that the drill-in fluid had stable rheological properties up to 250˚F over 24 hrs. The removal efficiency of the filter cake was nearly 100% and the return permeability was about 100% for Indiana limestone and Berea sandstone cores, when using a weight ratio of polylactic acid to calcium carbonate 3 to 1. GLDA (pH 3.3) and HEDTA (pH 4) can be used to remove the filter cake in one step without using α-amylase enzyme solutions. GLDA (20 wt% in a 200 g solution and pH of 3.3) and HEDTA (20 wt% in a 200 g solution and pH 4) had 100% removal efficiency of the filter cake using Indiana limestone and Berea sandstone cores. Chelate solutions, GLDA (pH of 3.3 - 13) and HEDTA (pH of 4 and 7) were incompatible with α-amylase enzyme solutions over a wide range of temperatures. CT results showed that no formation damage was observed when using chelating agents as a breaker to remove the calcium carbonate filter cake. Manganese tetraoxide-based filter cake had a removal efficiency of 85% after 20 hrs soaking with glycolic acid (5 wt%) after soaking with α-amylase for 24 hrs, and 89% after reaction with acid mixture (1 wt% HCl and 7 wt% glycolic acid) for 16 hrs. for both methods, the retained permeability was 100% for Indiana limestone cores and 120% for Berea sandstone cores, which indication maximum productivity of these formations. Ilmenite-based filter cake was ideal for HPHT applications, 0.2 in. thickness and 12 cm3 filtrate under dynamic conditions. The filtrate volume was reduced by adding a minor amount of CaCO3 solids that improved the particles packing. No sag problem was observed when using the micronized ilmenite in water-based drilling fluids. Ilmenite has a negative zeta potential in alkaline media and had a stable dispersion in water at pH > 7.