Water is a fundamental part of life as we know it, and by that also a fundamental for biology, chemistry, and parts of physics. Understanding how water behaves and interacts is key in many fields of all these three branches of science. Numerical simulation using molecular dynamics can aid in building insight in the behavior and interactions of water. In this thesis molecular dynamics is used to simulate common rigid 3 point water models to see how well they replicate certain physical and chemical properties as functions of temperature. This is done with molecular dynamics program GROMACS which offers a complete set of tools to run simulations and analyze results. Everything has been automated to work with a python script and a file of input parameters. Most of the models follow the same trends and are valid within a limited temperature range. / Vatten är en av de fundamentala byggstenarna för liv, därmed är det även fundamentalt för biologi, kemi och delar av fysiken. Att förstå hur vatten beter sig och interagerar är en stor fråga inom dessa tre grenar av vetenskap. Med molekyldynamik går det att utföra numeriska simuleringar som kan användas som hjälpmedel för att bygga en djupare förståelse för riktigt vatten. I den här uppsatsen så har molekyldynamik använts till att simulera vanliga rigida 3 punkts parametiseringar av vatten för att se hur bra de kan replikera vissa egenskaper som funktioner av temperatur. Simuleringen är gjord med hjälp av molekyldynamik programet GROMACS som ger en fullständig uppsättning verktyg för att simulera och analysera molekylsystem. Alla simuleringar och analys är automatiserat med ett pythonprogram och en fil för parametrar. De allra flesta modeller följer liknande trender och är giltiga inom små temperaturintervall.

Extended aqueous systems, crystalline ice and liquid water, are studied computationally to investigate their ground state and excited state properties. Methods from solid state physics and quantum chemistry are combined to shed light on some of the unusual properties of water and ice. For the ground state of crystalline ice, density functional theory (DFT) calculations are compared to an ab initio incremental ansatz that utilizes periodic Hartree-Fock together with localized electron correlation calculations. It is shown that the many-body decomposition of the electron correlation converges very fast, allowing the achievement of excellent agreement with experimental data even when limiting correlation energy contributions to two-body terms only. The incremental method is utilized by a computer program that combines the periodic and localized calculations, and allows for structural optimization of the system of interest. The adsorption of water molecules on the surface of ice is studied using DFT. Adsorption is found to be favoured on non-crystallographic adsorption sites, and a slight tendency towards the formation of rough surfaces is reported. The localization of excess electrons at the surface of ice is facilitated by coadsorbed water molecules. For a correct theoretical description of the latter, a self-interaction correction scheme for the excess electron has to be used. However, it is sufficient to limit the self-interaction correction to the excess electron only, since the neutral ice surface itself is well described within conventional DFT. The self-interaction correction scheme is incorporated into a commonly used DFT program package. Optical excitations of crystalline ice are calculated using many-body perturbation theory. Solving the two-particle Bethe-Salpeter equation yields optical spectra in excellent agreement with experimental data. Based on this agreement, an embedding model is developed that reduces the hydrogen bond network to its most important contribution. The model is applied to crystalline ice, where it reproduces the experimental spectral features, and to microscopic liquid water structures obtained from molecular dynamics simulations, where it reproduces the energy shift of the first absorption peak and gives overall good agreement with experiment. The driving force of water’s anomalous optical behaviour is identified.

<p>Diffusion of liquids into and through polymers is an important factor that negatively may influence the durability or lifetime of a polymer structure used in industrial applications. In this work two types of polymers, a liquid crystalline polymer (LCP, Vectra A950) and various thermoset resins as used in fibre reinforced plastics (FRP) process equipment were studied with regard to barrier properties, chemical resistance and long-term performance. LCP are known for their outstanding chemical resistance and barrier properties. FRP used in process equipment may be a cost-efficient solution in chemically aggressive environments where standard carbon or stainless steel cannot be used due to its limited corrosion resistance. Transport properties of typical industrial environments were determined for the LCP and the influence of annealing and orientation was investigated to study whether the barrier properties can be improved. The possibility to use LCP as cost-effective lining for FRP was explored. Special focus was put on the diffusion of water and its effect on long-term transport properties and stability of thermoset resins as the performance of FRP is strongly related to the diffusion of water. </p><p>The results showed that Vectra A950 was suitable for organic solvent and non-oxidising acid environments. Its transport properties were gravimetrically determined and found to be 10 to 102 times lower than that of a high barrier fluoropolymer of type FEP. The degree of molecular packing increased with annealing time both below and above the melting point. Below the melting point this was – at least – partly due to crystal formation whereas above the melting point other mechanisms were involved. The effects of annealing and orientation on the transport properties in LCP were, however, very small or not significant and probably significantly longer annealing times are required. LCP has potential to be used as lining material for FRP as the use of an LCP-lining substantially reduced the permeability of and the solute sorption in a bisphenol A epoxy-based vinyl ester resin. The bonding strength was improved significantly by a combined abrasive and oxygen plasma treatment.</p><p>The long-term sorption of water in thermoset resins including bisphenol A epoxy-based vinyl ester, novolac-based vinyl ester, urethane modified vinyl ester and bisphenol A polyester resins was found to increase with exposure time whereas the diffusion coefficient was not significantly affected. It was shown that the presence of water induced relaxation processes that were considered to be the primarily reason for the increase in sorption coefficient in comparison to degradation processes, such as hydrolysis, causing osmotic processes. A general relationship for the estimation of the sorption coefficient at 80ºC in dependence of the water activity and the sorption coefficient at unit activity independent of the resin type was established.</p>

Diffusion of liquids into and through polymers is an important factor that negatively may influence the durability or lifetime of a polymer structure used in industrial applications. In this work two types of polymers, a liquid crystalline polymer (LCP, Vectra A950) and various thermoset resins as used in fibre reinforced plastics (FRP) process equipment were studied with regard to barrier properties, chemical resistance and long-term performance. LCP are known for their outstanding chemical resistance and barrier properties. FRP used in process equipment may be a cost-efficient solution in chemically aggressive environments where standard carbon or stainless steel cannot be used due to its limited corrosion resistance. Transport properties of typical industrial environments were determined for the LCP and the influence of annealing and orientation was investigated to study whether the barrier properties can be improved. The possibility to use LCP as cost-effective lining for FRP was explored. Special focus was put on the diffusion of water and its effect on long-term transport properties and stability of thermoset resins as the performance of FRP is strongly related to the diffusion of water. The results showed that Vectra A950 was suitable for organic solvent and non-oxidising acid environments. Its transport properties were gravimetrically determined and found to be 10 to 102 times lower than that of a high barrier fluoropolymer of type FEP. The degree of molecular packing increased with annealing time both below and above the melting point. Below the melting point this was – at least – partly due to crystal formation whereas above the melting point other mechanisms were involved. The effects of annealing and orientation on the transport properties in LCP were, however, very small or not significant and probably significantly longer annealing times are required. LCP has potential to be used as lining material for FRP as the use of an LCP-lining substantially reduced the permeability of and the solute sorption in a bisphenol A epoxy-based vinyl ester resin. The bonding strength was improved significantly by a combined abrasive and oxygen plasma treatment. The long-term sorption of water in thermoset resins including bisphenol A epoxy-based vinyl ester, novolac-based vinyl ester, urethane modified vinyl ester and bisphenol A polyester resins was found to increase with exposure time whereas the diffusion coefficient was not significantly affected. It was shown that the presence of water induced relaxation processes that were considered to be the primarily reason for the increase in sorption coefficient in comparison to degradation processes, such as hydrolysis, causing osmotic processes. A general relationship for the estimation of the sorption coefficient at 80ºC in dependence of the water activity and the sorption coefficient at unit activity independent of the resin type was established.

<p>This study tested a dynamic modelling approach based on salt application, meteorological data and generic descriptions of hydrogeological environments for describing the spread of deicing salt to the surroundings and the corresponding increase in chloride storage in soil. Both the amount of chloride storage and the annual variation pattern were significantly altered due to deicing salt application and spread to the roadside environment. Data from field investigations comprising different hydrogeological environments and different methods of measurement were used to examine the variability of the salt deposition pattern in the vicinity of the road, and to test the performance of the model with respect to different soils and vegetation types. The use of typical hydrogeological environments to represent inputs to the model was shown to be useful to demonstrate the importance of soils, vegetation type and groundwater conditions for modelling the impact of deicing salt on soil water and the response to environmental changes in the vadose zone. However, the use of hydrogeological environment could also be misleading in view of the high degree of variability at the field scale. The different methods of measurements and simulations represented different spatial and temporal scales that were shown to be complementary useful to quantify the different pathways of deicing salt in the roadside environment. Continuous simulations complemented with selected field monitoring should therefore be promoted.</p> / QC 20100526

abstract: The optical valley of water, where water is transparent only in the visible range, is a fascinating phenomenon and cannot be modeled by conventional dielectric material modeling. While dielectric properties of materials can be modeled as a sum of Lorentz or Debye simple harmonic oscillators, water is the exception. In 1992 Diaz and Alexopoulos published a causal and passive circuit model that predicted the window of water by adding a “zero shunt” circuit in parallel with every Debye and Lorentz circuit branch. Other than the Diaz model, extensive literature survey yielded no universal dielectric material model that included water or offered an explanation for this window phenomenon. A hybrid phenomenological model of water, proposed by Shubitidze and Osterberg, was the only model other than the Diaz-Alexopoulos model that tried to predict and match the optical valley of water. However, we show that when we apply the requirement that the permittivity function must be a complex analytic function, it fails our test of causality and the model terms lack physical meaning, exhibiting various mathematical and physical contradictions. Left with only the Diaz proposed fundamental model as the only casual model, this dissertation explores its physical implications. Specifically, the theoretical prescription of Kyriazidou et al for creating artificial dielectric materials with a narrow band transparency is experimentally demonstrated for the first time at radiofrequencies. It is proposed that the most general component of the model of the frequency dependent permittivity of materials is not the simple harmonic oscillator but rather the harmonic oscillator augmented by the presence of a zero shunt circuit. The experimental demonstration illustrates the synthesis and design of a new generation of window materials based on that model. Physically realizable Lorentz coatings and RF Debye “molecules” for creating the desired windows material are designed using the full physics computational electromagnetic code. The prescribed material is then implemented in printed circuit board technology combined with composite manufacturing to successfully fabricate a lab demonstrator that exhibits a narrow RF window at a preselected frequency of interest. Demonstrator test data shows good agreement with HFSS predictions. / Dissertation/Thesis / Doctoral Dissertation Materials Science and Engineering 2017

This master `s thesis deals about the dielectric properties of water. It describes the basic chemical and physical properties of water and its distribution in terms of structure. It also describes the basic parameters of distilled water, deionized and superclean. In the chapter number 5 described the behavior of dielectrics in an electric field, determining the dipole moment by Claus-Mossotti 'equation, measurement of permittivity and loss factor. Practical part is consists of the design of the electrode systém, of measuring the water quality and evaluation of measured data

This study tested a dynamic modelling approach based on salt application, meteorological data and generic descriptions of hydrogeological environments for describing the spread of deicing salt to the surroundings and the corresponding increase in chloride storage in soil. Both the amount of chloride storage and the annual variation pattern were significantly altered due to deicing salt application and spread to the roadside environment. Data from field investigations comprising different hydrogeological environments and different methods of measurement were used to examine the variability of the salt deposition pattern in the vicinity of the road, and to test the performance of the model with respect to different soils and vegetation types. The use of typical hydrogeological environments to represent inputs to the model was shown to be useful to demonstrate the importance of soils, vegetation type and groundwater conditions for modelling the impact of deicing salt on soil water and the response to environmental changes in the vadose zone. However, the use of hydrogeological environment could also be misleading in view of the high degree of variability at the field scale. The different methods of measurements and simulations represented different spatial and temporal scales that were shown to be complementary useful to quantify the different pathways of deicing salt in the roadside environment. Continuous simulations complemented with selected field monitoring should therefore be promoted. / QC 20100526

This master´s thesis deals about insulation and dielectric properties of water. It describes the structure of water, covalent and hydrogen bonds. It outlines primary chemical and physical properties of water and then it describes parameters of water - dynamic viscosity, conductivity, surface tension, pH and also describes dielectric properties - dielectric loss, loss factor, permittivity, polarization. Part of the work is practical section, which includes measurements of deionized water, destilled water, tap water and shows primary dependence such as dependence loss factor on frequency or relative permittivity on frequency.

O presente trabalho versa sobre a gestão dos recursos hídricos sob a ótica dos princípios ambientais. O acesso à água é um direito humano fundamental. A implementação desse direito encontra-se dificultada em razão do contexto fático global de crise da água. As causas e conseqüências da escassez quali-quantitativa da água estão relacionadas diretamente ao homem, da mesma forma que seu necessário enfrentamento depende de mudanças de percepção e comportamento do próprio ser humano. Preconiza-se o rompimento do paradigma antropocentrista, que deve ser transmutado para uma visão ecocêntrica. A efetivação do direito fundamental de que se trata depende de inúmeras providências, destacando-se a publicização integral da propriedade da água pela Constituição de 1988. A finalidade dessa relevante alteração no regime de dominialidade hídrica foi dar ao Estado o meio para o adequado gerenciamento da água como forma de estabilizar ou reduzir a crise e promover justiça social. Compete ao Estado social a satisfação do bem-estar coletivo, o que é mais factível se tiver sob seu domínio o recurso atualmente escasso e de relevância pública. Os recursos hídricos ingressam no patrimônio estatal na categoria dos bens de uso comum do povo. Apesar disso, sua gestão se dá de forma descentralizada e participativa. Na tarefa de administrar as águas, o jurista utiliza-se dos princípios estruturantes do Direito Ambiental, notabilizando-se os princípios materiais do desenvolvimento sustentável, prevenção, precaução, poluidor-pagador e usuário-pagador. Todos eles estão previstos pela Constituição Federal. O desenvolvimento sustentável é um sobreprincípio, sendo mais do que um princípio. O critério de ponderação que é utilizado para solver o conflito entre princípios, no caso do ecodesenvolvimento aplica-se apenas entre seus elementos internos, não entre o desenvolvimento sustentável e outros princípios. Este princípio-reitor é muito útil na apreciação do modelo de produção de energia hidrelétrica, que causa degradações ambientais significativas, e sempre tem repercussão, também, nos planos econômico e social. Os princípios da prevenção e da precaução servem à proteção dos mananciais superficiais e subterrâneos. A precaução, porém, auxilia de forma mais apropriada na defesa das águas subterrâneas, uma vez que o estado da técnica não permite mensurar qual o impacto ambiental do consumo excessivo de água de poços, que consiste em uma realidade contemporânea crescente. Os princípios do poluidor-pagador e do usuário-pagador fundamentam teoricamente o instrumento da cobrança pela utilização dos recursos hídricos, que o legislador resolveu adotar como forma de incentivar a racionalização do uso da água. A pesquisa é do tipo bibliográfica. O método-base adotado é o analítico. Diversas formas de análise foram empregadas, registrando-se a estruturalista, a histórica e a descritiva. Como a adoção de um método-base não afasta a aplicação dos demais, pois cada trabalho científico acaba sendo construído de modo singular, utilizaram-se também, ao longo da dissertação, os métodos dialético, hermenêutico e sistêmico. / Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-05-15T16:32:50Z No. of bitstreams: 1 Dissertacao Eduardo C Viegas.pdf: 909624 bytes, checksum: 5542d0380064804357b53f30abdf1bfb (MD5) / Made available in DSpace on 2014-05-15T16:32:50Z (GMT). No. of bitstreams: 1 Dissertacao Eduardo C Viegas.pdf: 909624 bytes, checksum: 5542d0380064804357b53f30abdf1bfb (MD5) / The present work concerns the natural water resource management under the evironmental principles. Access to water is a basic human right. The implementation of this right is made all the more difficult on account of the global water crisis. The causes and consequences of these quality and quantity shortages of fresh water are directly related to man, likewise, in adequately facing this problem, a change in perception and behavior must be undertaken by humankind. A move away from the pattern of anthropocentrism to a more ecocentric view is needed. Carrying out these basic laws depends on innumerable steps, clarified in the integral publication of water properties in the constitution of 1988. The objective of this relevant alteration in water property was to give the state the means for the adequate management of water as a form of stabilizing or reducing the crisis and promoting social justice. It is the responsibility of the state to see to collective well being, which is made easier when the resource, which is presently scarce, is held under it s domain of public relevance. Natural water resources are held under the category of common use resources within the patrimony of the state. Despite this, it is managed in a decentralized and collaborative fashion. In the task of managing these water resources, the jurist uses the structured principles of Environmental Law, observing the main principles of sustainable development, prevention, precaution, paying pollutant and paying user. All of which have been foreseen by the Federal constitution. Sustainable development is more than a principle. The basis of consideration used to solve the conflict between the principles, in the case of eco-development is only applied within its internal elements, not within sustainable development and other principles. This fundamental principle is very useful in the appreciation of the model of production of hydroelectric energy, which causes significant environmental degradation and always has repercussions within economic and social plans. Precaution, however, acts as a more appropriate method of protecting subterranean waters, whereby the technical state no longer permits the measuring of the environmental impact of excessive consumption of well water, which includes a growing contemporary reality. The principles of the paying pollutant and the paying user theoretically substantiate the instrument of collective use of natural water resources, which the legislator resolved to adopt in order to stimulate rationing in the use of water. The research is in a bibliographical format. The method-base is analytical. Various forms of analysis were used, including structuralistic, historic and descriptive types. As the adoption of a certain method-base does not dismiss the need of others, so each scientific project is formed in a singular fashion, including, within the dissertation, dialectic, hermeneutic and systemic methods.