Chickpea is a food legume crop grown in tropical, sub-tropical and temperate regions. World chickpea production is roughly three times that of lentils. Among pulse crops marketed as human food, world chickpea consumption is second only to dry beans. Turkey, Australia, Syria, Mexico, Argentina and Canada are major chickpea exporters. There are two types of chickpea, namely, the kabuli and the desi. The kabuli type is grown in temperate regions while the desi type chickpea is grown in the semi-arid tropics. Chickpea is valued for its nutritive seeds with high protein and starch content. They are eaten fresh as green vegetables, parched, fried, roasted, and boiled, as snack food, dessert and condiments. The seeds are ground and the flour can be used in soup, dhal and bread. Cooked chickpea is mostly preferred by consumers, especially the kabuli type. In this thesis, the heat and moisture transfer behavior of kabuli chickpea when subjected to cooking at different temperatures was investigated. The thermo-physical properties of chickpea were studied to develop a model to simulate the temperature distribution and moisture absorption in a chickpea seed when cooked in water. The thermo-physical properties determined experimentally were thermal conductivity, specific heat, moisture diffusivity, particle density and moisture content. Thermal diffusivity was calculated using the experimental values of thermal conductivity, specific heat and density. The water absorption in chickpea was determined when the seeds were soaked at different temperatures. It was observed that as the temperature of the soaking medium was increased, the rate of moisture absorption also increased. Soaking was done to enhance the gelatinization process during cooking. Cooking experiments were conducted for boiling temperatures ranging from 70 to 98°C for both soaked and unsoaked seeds. It resulted in the soaked seeds being cooked within 40-50 min, whereas the unsoaked seeds took around 250-300 min to cook. The amount of soluble solids lost during the cooking process is also reported which enables to predict the optimum soaking and cooking temperature. Using linear regression simple models for dependency of thermal conductivity, specific heat, thermal diffusivity and density on temperature and moisture content were developed. The rate of moisture transfer and the center temperature in the seed during cooking was determined experimentally and also simulated with the constant thermal properties found experimentally. The closeness of the simulated and experimental results was proved by appropriate statistical analysis. Based on the results obtained, it can be understood that soaking the chickpea seeds at temperatures ranging from 25 to 40°C for 8 h and cooking it at higher temperatures ranging from 90 to 100°C will improve the quality of the cooked seed with minimum mass loss. This optimum condition saves both energy and time.

Chickpea is a food legume crop grown in tropical, sub-tropical and temperate regions. World chickpea production is roughly three times that of lentils. Among pulse crops marketed as human food, world chickpea consumption is second only to dry beans. Turkey, Australia, Syria, Mexico, Argentina and Canada are major chickpea exporters. There are two types of chickpea, namely, the kabuli and the desi. The kabuli type is grown in temperate regions while the desi type chickpea is grown in the semi-arid tropics. Chickpea is valued for its nutritive seeds with high protein and starch content. They are eaten fresh as green vegetables, parched, fried, roasted, and boiled, as snack food, dessert and condiments. The seeds are ground and the flour can be used in soup, dhal and bread. Cooked chickpea is mostly preferred by consumers, especially the kabuli type. In this thesis, the heat and moisture transfer behavior of kabuli chickpea when subjected to cooking at different temperatures was investigated. The thermo-physical properties of chickpea were studied to develop a model to simulate the temperature distribution and moisture absorption in a chickpea seed when cooked in water. The thermo-physical properties determined experimentally were thermal conductivity, specific heat, moisture diffusivity, particle density and moisture content. Thermal diffusivity was calculated using the experimental values of thermal conductivity, specific heat and density. The water absorption in chickpea was determined when the seeds were soaked at different temperatures. It was observed that as the temperature of the soaking medium was increased, the rate of moisture absorption also increased. Soaking was done to enhance the gelatinization process during cooking. Cooking experiments were conducted for boiling temperatures ranging from 70 to 98°C for both soaked and unsoaked seeds. It resulted in the soaked seeds being cooked within 40-50 min, whereas the unsoaked seeds took around 250-300 min to cook. The amount of soluble solids lost during the cooking process is also reported which enables to predict the optimum soaking and cooking temperature. Using linear regression simple models for dependency of thermal conductivity, specific heat, thermal diffusivity and density on temperature and moisture content were developed. The rate of moisture transfer and the center temperature in the seed during cooking was determined experimentally and also simulated with the constant thermal properties found experimentally. The closeness of the simulated and experimental results was proved by appropriate statistical analysis. Based on the results obtained, it can be understood that soaking the chickpea seeds at temperatures ranging from 25 to 40°C for 8 h and cooking it at higher temperatures ranging from 90 to 100°C will improve the quality of the cooked seed with minimum mass loss. This optimum condition saves both energy and time.

This dissertation is concerned with the understanding of physico-chemical properties of energetic materials (EMs). Recently, a substantial amount of work has been directed towards calculations of equations of state and structural changes upon compression of existing EMs, as well as elucidating the underlying chemistry of initiation in detonating EMs. This work contributes to this effort by 1) predicting equations of state and thermo-physical properties of EMs, 2) predicting new phases of novel EMs, and 3) examining the initial stages of chemistry that result in detonation in EMs. The motivation for the first thrust, is to provide thermodynamic properties as input parameters for mesoscale modeling. Such properties are urgently sought for a wide range of temperatures and pressures, and are often difficult or even impossible to obtain from experiment. However, thermo-physical properties are obtained by calculating structural properties and vibration spectra using density function theory and employing the quasi-harmonic approximation. The second thrust is directed towards the prediction and investigation of novel polymorphs of known azide compounds to identify precursor materials for synthesis of polymeric nitrogen EMs. Structural searches are used to identify new polymorphs, while theoretical Raman spectra for these polymorphs are calculated to aid experimentalists in identifying the appearance of these azide compounds under high pressure. The final thrust is concerned with elucidating the initial chemical events that lead to detonation through hypervelocity collision simulations using first-principles molecular dynamics. The chemical mechanisms of initiation are determined from the atomic trajectory data, while heats of reaction are calculated to quantify energy trends of chemical transformations.

Sweden has 350 ice rinks in operation which annually use approximately 1000 MWh each. Therefrigeration system usually accounts for about 43 % of the total energy consumption which is the largestshare of the major energy systems. Besides improving the facilities one-by-one, it is important todistinguish common features that will indicate the potential energy saving possibilities for all ice rinks.More than 97 % of the Swedish ice rinks use indirect refrigeration systems with a secondary fluid.Moreover, the thermo-physical properties of secondary fluids directly impact the heat transfer andpressure drop. Thus, assessing and quantifying their influence on the refrigeration system performance isimportant while estimating the energy saving potential for the ice rinks.A theoretical model as well as two case studies focusing on the importance of the secondary fluid choiceare investigated. The theoretical model calculations are performed assuming the steady-state conditionsand considering a fixed ice rink design independently on the secondary fluid type. Hence, they can becompared on the same basis. According to this theoretical model, the refrigeration efficiency rankingstarting from the best to the worst for secondary fluid is: ammonia; potassium formate; calcium chloride;potassium acetate; ethylene glycol; ethyl alcohol; and propylene glycol. Secondary fluids can be ranked inexactly the same order starting from the lowest to the highest value in terms of the dynamic viscosity. Itwas shown that potassium formate has the best heat transfer properties while ammonia leads to the lowestpressure drops and pumping power. Propylene glycol shows the worst features in both cases. Ammoniaand potassium formate show respectively 5% and 3% higher COP than calcium chloride for typical heatloads of 150 kW. When controlling the pump over a temperature difference ΔT, the existence of theoptimum pump control or optimum flow was highlighted. For common heat loads of 150 kW thisoptimum pump control ΔT is around 2,5 K for calcium chloride while it is around 2 K for ammonia. It isshown that the secondary fluids having laminar flow in the ice rink floor pipes have a larger share in theconvection heat transfer resistance (~20-25 %) than the secondary fluids experiencing turbulent flow (~3%).One of the case studies shows a potential energy saving of 12 % for the refrigeration system whenincreasing the freezing point of the secondary fluid. An energy saving of 10,8 MWh per year was foundfor each temperature degree increase in the secondary fluid freezing point.

Made available in DSpace on 2014-12-17T14:57:53Z (GMT). No. of bitstreams: 1 ManoelLON_TESE.pdf: 2837089 bytes, checksum: 962b0c298a9cc0d199caa357de4ce608 (MD5) Previous issue date: 2012-02-16 / In the execution of civil engineering works, either by wasting during the coating of wall or demolition of gypsum walls, the generation of the gypsum waste involves serious environmental concerns. These concerns are increased by the high demand of this raw material in the sector and by the difficulties of proper disposal byproduct generated. In the search for alternatives to minimize this problem, many research works are being conducted, giving emphasis in using gypsum waste as fillers in composites materials in order to improve the acoustic, thermal and mechanical performances. Through empirical testing, it was observed that the crystallization water contained in the residue (CaSO4.2H2O) could act like primary agent in the expanding of the polyurethane foam. Considering that polyurethane produced from vegetable oils are biodegradable synthetic polymers and that are admittedly to represent an alternative to petrochemical synthetic polyurethane, this research consist an analysis of the thermal behavior of a composite whose matrix obtained from a resin derived from the expansive castor oil seed, with loads of 4%, 8%, 12% and 16% of gypsum waste replacing to the polyol prepolymer blend. Contributors to this analysis: a characterization of the raw material through analysis of spectroscopy by Fourier transform infrared (FTIR), chemical analysis by X-Ray Fluorescence (XRF) and mineralogical analysis by X Ray Diffraction (XRD), complemented by thermo gravimetric analysis (TGA). In order to evaluate the thermo physical properties and thermal behavior of the composites manufactured in die closed with expansion contained, were also carried tests to determine the percentage of open pore volume using a gas pycnometer, scanning electronic microscopy (SEM), in addition to testing of flammability and the resistance to contact with hot surfaces. Through the analysis of the results, it appears that it is possible to produce a new material, which few changes in their thermo physical properties and thermal performance, promotes significant changes and attractive to the environment / Na execu??o de obras na constru??o civil, seja por desperd?cio de gesso durante o revestimento de paredes ou na demoli??o de paredes de gesso acartonado, a gera??o do res?duo implica em preocupa??es ambientais decorrentes da alta demanda dessa mat?ria prima no setor e da dificuldade de destina??o adequada ao subproduto gerado. Na busca por uma alternativa que atenue o problema, muitas pesquisas t?m sido realizadas com ?nfase na utiliza??o do res?duo de gesso como carga em comp?sitos, com o intuito de melhorar os desempenhos ac?stico, t?rmico e mec?nico. Atrav?s de ensaios emp?ricos, observou-se que a ?gua de cristaliza??o contida no res?duo (CaSO4.2H2O) pode atuar como agente prim?rio no processo de expans?o de espumas de poliuretano. Considerando que os poliuretanos, derivados de ?leos vegetais, s?o pol?meros sint?ticos biodegrad?veis e que, reconhecidamente, representam uma alternativa aos poliuretanos sint?ticos petroqu?micos, a presente pesquisa procura fazer uma an?lise do comportamento t?rmico de um comp?sito desenvolvido com matriz de resina vegetal derivada do ?leo de mamona, com cargas de 4%, 8%, 12% e 16% de res?duo de gesso em substitui??o ? mistura poliol + pr?-pol?mero. Contribu?ram para esta an?lise: caracteriza??o da mat?ria prima por meio de espectroscopia de absor??o na regi?o do infravermelho por transformada de Fourier (FTIR), an?lise qu?mica por FRX e mineral por DRX e an?lise termogravim?trica (TGA e DTA). Com o prop?sito de avaliar as propriedades termof?sicas e o comportamento t?rmico dos comp?sitos produzidos com expans?o contida por fechamento do molde. Tamb?m foram realizados ensaios para determina??o do percentual de poros abertos, por meio de picn?metro a g?s, morfologia dos comp?sitos (MEV), al?m de ensaios de inflamabilidade e de resist?ncia ao contato com superf?cies aquecidas. Mediante a an?lise dos resultados obtidos, constatou-se a possibilidade de produ??o de um novo material para isola??o t?rmica, apresentando poucas altera??es em suas propriedades Termof?sicas, assim como em seu desempenho t?rmico, promovendo altera??es significativas e atraentes ao meio ambiente