Water is an important substance. It is part of us, of our environment, and is a fundamental prerequisite for the existence of life as we know it. The structure of water is still, after over 100 years of research on the subject, however under debate. In this thesis x-ray absorption spectroscopy (XAS) and reverse Monte Carlo (RMC) modeling are used to search for structural solutions of water consistent with many different experimental data sets, with emphasis on the combination of different experimental techniques for a reliable structure determination. Neutron and x-ray diffraction are analyzed in combination with the more recent synchrotron radiation based XAS. Geometrical criteria for H-bonding are implemented in RMC to drive the fits and allow to evaluate differently H-bonded structure models against the data. It is shown that the available diffraction data put little constraints on the type of H-bond topology or O-O-O tetrahedrality for the structure of liquid water. It is also demonstrated that classical MD simulations, using some of the most common interaction potentials for water, give rise to O-O and O-H pair-correlation functions with too sharp first peaks at too short distances to be in agreement with diffraction, and furthermore that requiring a large fraction of broken H-bonds is not in itself enough for a structure model to reproduce the experimental XAS. A contribution to the theoretical description of XAS is made by an in-depth investigation of important technical aspects of the TP-DFT spectrum calculations. A novel approach to RMC, applicable also to data that require a significant amount of computer time to evaluate, is developed which makes use of pre-computed properties from a large set of local geometries allowing RMC simulations directly on data from core-level spectroscopies such as XAS. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4, 5 and 6: Submitted

O estudo da interação de moléculas orgânicas com a água é de grande importância para diversas áreas das ciências, como por exemplo, na compreensão de sistemas biológicos. Uma elevada diversidade de estudos nesta área já foram realizados, no entanto, alguns aspectos do estudo de filmes finos de aminas anfifílicas não foram satisfatoriamente esclarecidos. Este trabalho aborda filmes de Langmuir de octadecilamina em função do pH e da força iônica de subfases aquosas, investigando a estrutura da monocamada orgânica e sua interação com a água, em diversos graus de ionização. Foi utilizada a Espectroscopia Vibracional por Geração de Soma de Frequências (Sum Frequency Generation - SFG), uma técnica que utiliza o princípio da óptica não-linear para estudar superfícies e interfaces, com o objetivo de investigar a conformação molecular dos filmes de Langmuir de aminas anfifílicas de cadeias longas, seu grau de ionização e a estrutura da água interagindo com a monocamada orgânica. Pôde-se acompanhar a ionização da monocamada em função do pH da subfase pela intensidade do modo de estiramento do grupo NH3+, e verificou-se que ela depende do pH local da interface, que por sua vez é alterado pela ionização da monocamada e é sensível à força iônica da subfase. A água interage com a monocamada via ligações de H com os grupos NH2/NH3+ e forma uma camada com alto grau de orientação perpendicular à superfície, mas relativamente desordenada do ponto de vista da rede de ligações de H (como na água líquida). A conformação das cadeias alquila depende da ionização do filme de Langmuir, sendo bastante compacta e ordenada a altos pHs (filme neutro) e mais expandida e desordenada a baixos pHs. Além disso, foram fabricados filmes de Langmuir-Blodgett (LB) de octadecilamina para comparar a estrutura dos filmes na superfície da água e em substratos sólidos. / The study of the interaction of organic molecules with water is of great importance for many areas of science, such as the understanding of biological systems. A large diversity of studies in this area have been performed, however some aspects of the study of thin films of amphiphilic amines have not been satisfactorily clarified. This dissertation focuses on Langmuir films of Octadecylamine as a function of pH and ionic strength of the aqueous subphase, investigating the structure of the organic monolayer and its interaction with water at various degrees of ionization. Sum-Frequency Vibrational Spectroscopy (SFG spectroscopy), a non-linear optical technique to study surfaces and interfaces, was used in order to investigate the molecular conformation of the Langmuir films, its degree of ionization and the structure of water interacting with the organic monolayer. The monolayer ionization could be monitored by the intensity of the NH3+ group stretch mode, and it was found that it depends on the local pH at the interface, which in turn is changed by the monolayer ionization and is sensitive to the subphase ionic strength. Water interacts with the monolayer by H bonds with NH2/NH3+ groups, forming a layer with a high degree of orientational order along the surface normal, but relatively disordered regarding the H-bonding network (like in the bulk liquid). The conformation of the alkyl chains depends on the monolayer ionization, being compact and all-trans at high pHs, but more expanded and disordered at low pHs. In addition, Langmuir-Blodgett (LB) films of Octadecylamine were fabricated to compare their structure on the solid substrate to those on the water surface

O atual modelo de cidade capitalista, voltado ao crescimento econômico, proporciona um desequilíbrio na estrutura sócio-ambiental das áreas urbanizadas, acarretando sérios problemas ambientais. A crise ambiental e a exclusão social levam à necessidade de formular novas propostas para o desenvolvimento sustentável, atreladas ao potencial ambiental e cultural da cidade ao longo da sua evolução urbana, estimulando trajetórias de maior qualidade socioambiental e um melhor preparo para lidar com as grandes tendências evolutivas e seus impactos. O desenvolvimento sustentável implica no reconhecimento da relação natureza-cultura; valorizando os recursos naturais e os sentidos culturais que mobilizam a construção social da história. É necessário vincular a complexidade ambiental ao processo de construção da identidade de um povo; seus costumes, tradições e crenças. A abordagem ecológica é a base para o resgate da relação afetiva cidadão-cidade, tendo como principais eixos de amarração o patrimônio cultural e os recursos hídricos, analisados de acordo com a evolução da cidade. A pesquisa tem como principal objetivo avaliar a qualidade socioambiental e desenvolvimento de novos cenários para um projeto urbano sustentável baseado na elaboração e aplicação do Selo LABVerde II, um selo de localização sustentável, e na análise da estrutura ecológica, hídrica e cultural do município de Itu, em especial a ligação entre o Centro Histórico e o Novo Centro da cidade. Este trabalho valorizará o potencial ambiental e cultural nos projetos urbanos, estabelecendo vínculos afetivos da sociedade com sua identidade e com os recursos naturais, incentivando possíveis intervenções dos órgãos públicos no planejamento urbano e na formulação de novos planos diretores, com o objetivo de proporcionar uma qualidade de vida melhor. / The current model of a capitalist city, focused on economic growth, provides a lack of balance at socio-environmental structure of urbanized areas, leading to serious environmental problems. Environmental crisis and social exclusion evoke the formulation of different proposals for sustainable development linked to the environmental and cultural potential of the city, along its urban evolution, stimulating trajectories of higher socio-environmental quality and better preparedness to deal with big evolutionary trends and impacts. Sustainable development implies recognition of nature - culture relationship; valuing the natural resources and cultural sensethose mobilize social construction of history. It is urgent to link environmental complexity to the process of building a people\'s identity; their customs, traditions and beliefs. Ecological approach is the basis for the rescue of the citizen-city affective relationship, having as main axes of mooring cultural heritage and water resources, analyzed according to the city evolution. The main objective of the research is to evaluate socio-environmental quality and develop new scenarios for a sustainable urban project, based on the elaboration and application of the LABVerde II Seal, a seal of sustainable location, analyzing ecological and water resources and cultural structure in the municipality of Itu - in special connection between Historic Center and New Center of the city. This work intend to value environmental and cultural potential in urban projects, establishing affective bonds of society, with its identity and natural resources, encouraging possible interventions by public agencies in urban planning and the formulation of new master plans formulation, looking for better life quality.

O atual modelo de cidade capitalista, voltado ao crescimento econômico, proporciona um desequilíbrio na estrutura sócio-ambiental das áreas urbanizadas, acarretando sérios problemas ambientais. A crise ambiental e a exclusão social levam à necessidade de formular novas propostas para o desenvolvimento sustentável, atreladas ao potencial ambiental e cultural da cidade ao longo da sua evolução urbana, estimulando trajetórias de maior qualidade socioambiental e um melhor preparo para lidar com as grandes tendências evolutivas e seus impactos. O desenvolvimento sustentável implica no reconhecimento da relação natureza-cultura; valorizando os recursos naturais e os sentidos culturais que mobilizam a construção social da história. É necessário vincular a complexidade ambiental ao processo de construção da identidade de um povo; seus costumes, tradições e crenças. A abordagem ecológica é a base para o resgate da relação afetiva cidadão-cidade, tendo como principais eixos de amarração o patrimônio cultural e os recursos hídricos, analisados de acordo com a evolução da cidade. A pesquisa tem como principal objetivo avaliar a qualidade socioambiental e desenvolvimento de novos cenários para um projeto urbano sustentável baseado na elaboração e aplicação do Selo LABVerde II, um selo de localização sustentável, e na análise da estrutura ecológica, hídrica e cultural do município de Itu, em especial a ligação entre o Centro Histórico e o Novo Centro da cidade. Este trabalho valorizará o potencial ambiental e cultural nos projetos urbanos, estabelecendo vínculos afetivos da sociedade com sua identidade e com os recursos naturais, incentivando possíveis intervenções dos órgãos públicos no planejamento urbano e na formulação de novos planos diretores, com o objetivo de proporcionar uma qualidade de vida melhor. / The current model of a capitalist city, focused on economic growth, provides a lack of balance at socio-environmental structure of urbanized areas, leading to serious environmental problems. Environmental crisis and social exclusion evoke the formulation of different proposals for sustainable development linked to the environmental and cultural potential of the city, along its urban evolution, stimulating trajectories of higher socio-environmental quality and better preparedness to deal with big evolutionary trends and impacts. Sustainable development implies recognition of nature - culture relationship; valuing the natural resources and cultural sensethose mobilize social construction of history. It is urgent to link environmental complexity to the process of building a people\'s identity; their customs, traditions and beliefs. Ecological approach is the basis for the rescue of the citizen-city affective relationship, having as main axes of mooring cultural heritage and water resources, analyzed according to the city evolution. The main objective of the research is to evaluate socio-environmental quality and develop new scenarios for a sustainable urban project, based on the elaboration and application of the LABVerde II Seal, a seal of sustainable location, analyzing ecological and water resources and cultural structure in the municipality of Itu - in special connection between Historic Center and New Center of the city. This work intend to value environmental and cultural potential in urban projects, establishing affective bonds of society, with its identity and natural resources, encouraging possible interventions by public agencies in urban planning and the formulation of new master plans formulation, looking for better life quality.

O estudo da interação de moléculas orgânicas com a água é de grande importância para diversas áreas das ciências, como por exemplo, na compreensão de sistemas biológicos. Uma elevada diversidade de estudos nesta área já foram realizados, no entanto, alguns aspectos do estudo de filmes finos de aminas anfifílicas não foram satisfatoriamente esclarecidos. Este trabalho aborda filmes de Langmuir de octadecilamina em função do pH e da força iônica de subfases aquosas, investigando a estrutura da monocamada orgânica e sua interação com a água, em diversos graus de ionização. Foi utilizada a Espectroscopia Vibracional por Geração de Soma de Frequências (Sum Frequency Generation - SFG), uma técnica que utiliza o princípio da óptica não-linear para estudar superfícies e interfaces, com o objetivo de investigar a conformação molecular dos filmes de Langmuir de aminas anfifílicas de cadeias longas, seu grau de ionização e a estrutura da água interagindo com a monocamada orgânica. Pôde-se acompanhar a ionização da monocamada em função do pH da subfase pela intensidade do modo de estiramento do grupo NH3+, e verificou-se que ela depende do pH local da interface, que por sua vez é alterado pela ionização da monocamada e é sensível à força iônica da subfase. A água interage com a monocamada via ligações de H com os grupos NH2/NH3+ e forma uma camada com alto grau de orientação perpendicular à superfície, mas relativamente desordenada do ponto de vista da rede de ligações de H (como na água líquida). A conformação das cadeias alquila depende da ionização do filme de Langmuir, sendo bastante compacta e ordenada a altos pHs (filme neutro) e mais expandida e desordenada a baixos pHs. Além disso, foram fabricados filmes de Langmuir-Blodgett (LB) de octadecilamina para comparar a estrutura dos filmes na superfície da água e em substratos sólidos. / The study of the interaction of organic molecules with water is of great importance for many areas of science, such as the understanding of biological systems. A large diversity of studies in this area have been performed, however some aspects of the study of thin films of amphiphilic amines have not been satisfactorily clarified. This dissertation focuses on Langmuir films of Octadecylamine as a function of pH and ionic strength of the aqueous subphase, investigating the structure of the organic monolayer and its interaction with water at various degrees of ionization. Sum-Frequency Vibrational Spectroscopy (SFG spectroscopy), a non-linear optical technique to study surfaces and interfaces, was used in order to investigate the molecular conformation of the Langmuir films, its degree of ionization and the structure of water interacting with the organic monolayer. The monolayer ionization could be monitored by the intensity of the NH3+ group stretch mode, and it was found that it depends on the local pH at the interface, which in turn is changed by the monolayer ionization and is sensitive to the subphase ionic strength. Water interacts with the monolayer by H bonds with NH2/NH3+ groups, forming a layer with a high degree of orientational order along the surface normal, but relatively disordered regarding the H-bonding network (like in the bulk liquid). The conformation of the alkyl chains depends on the monolayer ionization, being compact and all-trans at high pHs, but more expanded and disordered at low pHs. In addition, Langmuir-Blodgett (LB) films of Octadecylamine were fabricated to compare their structure on the solid substrate to those on the water surface

No description available.

Ziel dieser Arbeit ist die Untersuchung der Ionenbindung an Polymeren und Lipidmembranen in wässrigen Lösungen. Im ersten Teil dieser Arbeit wurde der Einfluss verschiedener anorganischer Salze und Polyelektrolyte auf die Struktur des Wassers mit Hilfe Isothermer Mikrotitrationskalorimetrie (ITC) erforscht. Die Verdünnungswärme der Salze wurde als Maß für die Fähigkeit der Ionen, die geordnete Struktur des Wassers zu stabilisieren oder zu zerstören, verwendet. Die Verdünnungswärmen konnten auf Hofmeister Effekte zurückgeführt werden. Im Anschluss daran wurde die Bindung von Ca2+ an Natrium- Poly(acrylsäure) (NaPAA) untersucht. Mit Hilfe von ITC und einer Ca2+- selektiven Elektrode wurde die Reaktionsenthalpie und Bindungsisotherme gemessen. Es wurde gezeigt, dass die Binding von Ca2+ - Ionen an NaPAA stark endotherm und daher entropiegetrieben ist. Anschließend wurde die Bindung von Ca2+ an die eindimensionale Polymerkette mit der an ein Lipidvesikel mit denselben funktioniellen Gruppen verglichen. Es wurde beobachtet, dass die Ionenbindung –wie auch im Fall des Polymers- endotherm ist. Ein Vergleich der Ca2+- Bindung an die Lipidmembran mit der an das Polymer konnte zeigen, dass das Ion schwächer an die Membran bindet. Im Zusammenhang mit diesen Experimenten wurde auch beobachtet, dass Ca2+ nicht nur an geladene, sondern auch an zwitterionische Lipidvesikel bindet. Schließlich wurde die Wechselwirkung zweier Salze, KCl and NaCl, mit einem neutralen Polymergel, PNIPAAM, und dem geladenen Polymer PAA untersucht. Mit Hilfe von Kalorimetrie und einer kaliumselektiven Elektrode wurde beobachtet, dass die Ionen mit beiden Polymeren wechselwirken, unabhängig davon, ob diese Ladungen tragen, oder nicht. / The goal of this work was to study the binding of ions to polymers and lipid bilayer membranes in aqueous solutions. In the first part of this work, the influence of various inorganic salts and polyelectrolytes on the structure of water was studied using Isothermal Titration Calorimetry (ITC). The heat of dilution of the salts was used as a scale of water structure making and breaking of the ions. The heats of dilution could be attributed to the Hofmeister Series. Following this, the binding of Ca2+ to poly(sodium acrylate) (NaPAA) was studied. ITC and a Ca2+ Ion Selective Electrode were used to measure the reaction enthalpy and binding isotherm. Binding of Ca2+ ions to PAA, was found to be highly endothermic and therefore solely driven by entropy. We then compared the binding of ions to the one-dimensional PAA polymer chain to the binding to lipid vesicles with the same functional groups. As for the polymer, Ca2+ binding was found to be endothermic. Binding of calcium to the lipid bilayer was found to be weaker than to the polymer. In the context of these experiments, it was shown that Ca2+ not only binds to charged but also to zwitterionic lipid vesicles. Finally, we studied the interaction of two salts, KCl and NaCl, to a neutral polymer gel, PNIPAAM, and to the ionic polymer PAA. Combining calorimetry and a potassium selective electrode we observed that the ions interact with both polymers, whether containing charges or not.

The Diploma Thesis focuses on the assessment of the current state of VD Tesetice to convert KPV parameters Q1000. Based on this evaluation, the thesis proposes corrective actions on waterwork constructions for the purpose of protection of their functioning during floods. Proposed corrective actions consist of designing new or additional safety features, mainly security spillway in abutment terrain.

Raman multivariate curve resolution (Raman-MCR) spectroscopy is used to study water-mediated interactions by decomposing Raman spectra of aqueous solutions into bulk water and solute-correlated (SC) spectral components. The SC spectra are minimum-area difference spectra that reveal solute-induced perturbations of water structure, including changes in water hydrogen-bonding strength, tetrahedral structure, and formation of dangling (non-hydrogen-bonded) OH defects in a solute's hydration shell. Additionally, Raman-active intramolecular vibrational modes of the solute may be used to uncover complementary information regarding solute--solute interactions. Herein, Raman-MCR is applied to address fundamental questions related to: (1) confined cavity water and its connection to host-guest binding, (2) hydrophobic hydration of fluorinated solutes, (3) specific ion effects on nonionic micelle formation, and (4) ion pairing in aqueous solutions.

Wissenschaftliche Untersuchungen von terrestrischen und aquatischen Ökosystemen erfordern präzise Informationen über die dreidimensionale Struktur des ökologischen Systems. Full-waveform Flugzeuglaserscannerdaten eignen sich hervorragend zur Charakterisierung von Ökosystemen und bilden eine ideale Basis für die vollständige volumetrische Repräsentation der Vegetations- und Gewässerstruktur in einem Voxelraum. Die Voxelattribute werden dabei aus der digitalisierten Wellenform abgeleitet. Jeder emittierte Laserpuls wird von Dämpfungseffekten beeinflusst, die durch Teilreflexionen auf seinem Weg durch die unterschiedlichen Vegetations- oder Wasserschichten entstehen. Dadurch ist die Struktur im unteren Bereich der empfangenen Rohsignale unterrepräsentiert. Die im Rahmen dieser Arbeit entwickelten innovativen Methoden zur Analyse von full-waveform Daten ermöglichen die Generierung einer radiometrisch korrigierten Voxelraumrepräsentation. Voraussetzung dafür ist die numerisch stabile Rekonstruktion des effektiven differentiellen Rückstreuquerschnitts mit geeigneten Entfaltungs- und Regularisierungsverfahren. Das Kernstück der Analyse bildet die Beschreibung der Signaldämpfung mit Hilfe geeigneter Modelle. Auf Grundlage dieser Modelle wurden neuartige Korrekturverfahren zur Kompensation der Signaldämpfung erarbeitet, wobei der Korrekturterm direkt aus dem differentiellen Rückstreuquerschnitt abgeleitet wird. Die Grundidee der entwickelten Methode ist das schrittweise Anheben der Signalintensität in Abhängigkeit von der individuellen Historie jedes Laserpulses. Die Resultate der vorliegenden Arbeit tragen dazu bei, die in full-waveform Daten enthaltenen Informationen über die Vegetations- und Gewässerstruktur zugänglich zu machen. Weiterhin zeigen die hier präsentierten Ergebnisse, dass die Limitierungen bestehender Auswertemethoden, welche weitgehend auf die Extraktion diskreter Maxima und die Erzeugung volumetrischer Repräsentationen aus diskreten 3D Punktwolken beschränkt sind, überwunden werden können. / The scientific investigation of terrestrial and aquatic ecosystems requires precise information on the three-dimensional structure of the ecologic system. Full-waveform airborne laser scanner data are an ideal basis for the complete volumetric representation of vegetation and water structure in a voxel space. Due to attenuation effects, caused by partial reflections during the laser pulse propagation through the vegetation or water column, each individual laser pulse echo is significantly modified. As a result, the structure in the lower parts of the vegetation or water column is underrepresented in the digitized waveform. Within this research, novel and innovative methods were developed, which enable the generation of a radiometrically correct voxel space representation. Therefore, a numerically stable reconstruction of the effective differential backscattering cross section utilizing appropriate deconvolution and regularization techniques is required. The essential element of the analysis is the description of the signal attenuation using applicable mathematical models. For this purpose, novel correction methods compensating the signal attenuation based on these models were developed. The correction term is directly derived from the differential backscatter cross section. The basic idea is a gradually increase of the signal amplitudes depending on the individual history of each laser pulse. The results gained in this work contribute to an improved access to the information on vegetation and water structure, contained in full-waveform laser scanner data. Furthermore, it is possible to overcome limitations of existing approaches, which are mainly based on the extraction of discrete maxima.