Despite comprehensive studies addressing the chemical kinetics of butanol isomers, relevant uncertainties associated with the emissions of relevant pollutants persists. Also, a lack of chemistry knowledge of processes designed to produce biofuels limits their implementation at industrial scales. Therefore, the first objective of this thesis was to use cutting-edge kinetic theories to calculate rate constants of propen-2-ol, 1-pronenol, and vinyl alcohol keto-enol tautomerizations, which account for the production of the harmful carbonyl species. The second objective was to use the predictive capabilities of dynamic theories to reveal new chemistry of syngas oxy-combustion in supercritical CO2 and complexities of the zeolite dealumination, two processes involved in coal and biomass conversion. Rate constants computations considered transition state theory with variational effects, tunneling correction, and multistructural torsional anharmonicity. The study also included pressure effects by using and improving the system-specific quantum Rice-Ramsperger-Kassel/modified strong collision model. The atomistic simulations used ReaxFF force fields in hydrogen/oxygen/carbon monoxide/ carbon dioxide mixtures to represent the syngas system and an MFI zeolite with different water loading to model the dealumination. The results show that the studied assisted tautomerizations have much lower energy barriers than the unimolecular process. However, the “catalytic” effect is efficient only if the partner molecule is at high concentrations. Pressure effects are pronounced in the chemically activated tautomerizations, and the improved algorithm to compute pressure-dependent rate constants overcomes the initial difficulties associated with its application to C3 or larger molecules at temperatures above 800-1000 K. Reactive molecular dynamics simulations revealed the role of CO2 as an initiator in the syngas oxy-combustion and a new step involving the formation of formic acid. Those simulations for the zeolite dealumination process also showed that proton transfer, framework flexibility, and aluminum dislodging mediated by silicon reactions are complex dynamic phenomena determining the process. These aspects complement the dealumination theory uncovered so far and establish new paths in the study of water-zeolite interactions. Overall, the rate constants computed in this work reduce relevant uncertainties in the chemical kinetic mechanisms of alcohol oxidation, and the molecular dynamics simulations broaden the chemical knowledge of processes aimed at the utilization of alternative energy resources.

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經濟發展與財富分配一直以來是國家所面臨的兩難處境。經濟發展的過程中不可避免會產生財富集中於特定階級的現象，所得極化產生的弊端使得歐美國家不得不採取公共政策介入工資協商。其一是制訂最低工資迫使資方給付此等數額以上之工資，其二則是以一組工資政策制度設計令勞工能以集體力量就工資與資方進行協商（或連同政府形成三方對談），此二政策皆是在避免分配問題惡化造成社會不安，同時兩者皆是試圖對市場工資進行規制，因而在效果上有重疊的部份，功能上也相互影響。最低工資政策與工資政策或分由國家與勞資雙方各別制訂，或皆在勞、資、政三方協商下形成，並沒有一固定模式出現，端視該國工業關係而異。 基本（最低）工資政策在我國則因特殊的工業關係與強勢的國家機關有著截然不同的發展。早期台灣的國家機關傾向追求經濟發展，在相對弱勢的社會團體（包含勞資雙方）之前對工資議題採嚴密控制的態度，避免工資受政治力量影響而造成台灣在國際市場上的比較利益優勢受損，因而在基本工資政策上採取謹慎調整、甚或不調整的策略。同時在工資政策上因工會的低度發展，工資協商只出現在少許產業，這使台灣的市場工資長期維持在一相當低的水準，具議價功能的工會如此發展更是因為國家機關政治動員與經濟動員策略對工會功能造成的扭曲。因而在早期台灣基本工資政策的效用不彰，團體協商也受到普遍的漠視。 然而1980年以後巨幅變遷的國際與國內政經環境迫使國家機關必須調整其在工資議題上的態度。首先在國際間來自主要出口貿易國對貿易條件的異議使得台灣不能再以低工資為其發展策略，這使得國家必須正視勞動基準與工會發展的問題；其次，後進亞洲國家與台灣在國際市場上競價的結果使得低工資產品的獲利空間日益縮小，因而台灣面臨產業結構調整的壓力，這使得國家機關毋需再刻意維持低市場工資的局面，反而需要制訂出較高的勞動基準迫使勞力密集產業自然淘汰或遷往海外，加速國內的產業升級；再者，國內政治民主化改變了國家-社會間的關係，蓬勃的勞工運動與變遷的政商關係使得工業關係也有了與以往不同的發展。在1988年基本工資審議辦法通過後，基本工資政策便進入了逐年審議調整的制度化階段，政府試圖將經濟發展所帶來的利益與勞工分享，降低發展過程中日益惡化的分配問題。但政院通過之基本工資與審議機制議定結果往往有相當大的差異，在制訂過程間不但各方在認知上有極大的落差，對制訂結果也是爭議不斷，這使得原先欲降低分配爭議的基本工資調整反而成為另一爭議的起源。 其中經濟部門不只一次表達廢除基本工資制度的看法，但我們可發現自1988年以後政府非但沒有廢止基本工資的跡象，其還是在爭議不斷的聲浪中逐年進行調整。我們認為政府對基本工資積極調整的態度與基本工資所連動的勞保投保工資有極大的關係。由於勞工保險在1980年代中期突然出現大幅虧損，同時人口結構老化、職業工會投保者日眾等結構性問題亦難以克服，逐年調整的基本工資便成為改善政府財政危機的一大利器。不過隨著外勞引進日增，同樣受到基本工資連動的外勞工資讓雇主團體對基本工資調整極為反彈，而諸多社會保險的開辦也令勞工團體在投保薪資調整上採取抵制的態度，反映在基本工資政策上便是基本工資與其他工資脫勾及勞資自由協商的聲浪日起。 1996年政府在基本工資政策上有了重大的調整，自1997年起將原先基本工資的政策草案形成委由勞資雙方先行協商，再由政院通過基本工資調整案。基本工資決策權雖仍在行政機關之手，但政策形成卻讓勞資雙方有了更大的參與空間。不過，日後的發展卻也印證了本研究的觀察，勞資雙方在社會保險工資上有著共同利益因而達成基本工資脫勾的協議，甚至為迴避基本工資調整對外勞工資的影響，1997年的勞資談判反而形成了製造業調薪3%的協議。然而最終還是因為我國工資政策制度設計的問題，這項協議並沒有通過，而基本工資調整還是回歸至行政機關完成。 本研究發現在台灣由於國家機關自主性與工業關係在不同階段有不同的發展，使得基本工資政策呈現出了不同的面貌。80年代之前，國家強大的自主性與組織勞動者的弱勢使得國家機關能夠充分遂行政權穩定與經濟成長的目的，國家機關排除任何影響工資決定制訂因素的結果使得台灣的市場工資長期維持在一相當低的幅度，卻也使得基本工資處於長期僵化的局面。然而，隨著政治民主化與工業關係的轉變，國家機關漸需正視民間社會對社會正當性的要求，合理分配利益的呼聲也日起；同時，國際政經環境的變遷也使得低工資出口的優勢不再，甚至可能因而生成貿易失衡的問題。這些因素皆使得政府在勞動政策上做出一連串改變，反映在基本工資政策上即是基本工資政策制度化與逐年調整原則的生成。但政策形成開放民間參與使得國家機關在制訂基本工資政策上的自主性逐漸降低，勞資利益衝突的問題日漸浮現；而社會安全網絡財政危機的加劇與外籍勞工的開放引進也為基本工資調整增添新的變數，進而影響基本工資政策的發展，使得台灣基本工資政策呈現出迥異於歐美國家的面貌。 第一章 緒論 第一節 研究動機、目的與範圍 第二節 文獻回顧 第二章 最低工資政策與工資政策 第一節 最低工資政策演進、概念與模式 一、工資制度之歷史演進 二、基本工資的政策概念與政策模式 第二節 發展中國家的最低工資政策與工資政策 第三章 理論架構 第一節 理論觀點--國家理論 一、社會中心觀點 二、國家中心觀點 三、Block與Offe的國家理論 第二節 研究途徑-歷史制度取向 第四章 台灣基本工資政策之形成與持續（1956-1987） 第一節 從經濟管制到經濟計畫 第二節 政策草案階段 第三節 低工資政策制度設計 第四節 小結 第五章 基本工資政策的發展與轉變（1988-1996） 第一節 工資政策的轉變 一、勞動政策的轉變 二、工業關係 第二節 制度化的基本工資政策 一、基本工資政策轉變的背景 二、基本工資政策的制度化過程 第三節 基本工資政策的轉變 一、基本工資公式政治化 二、外勞工資之因素 三、勞保財務因素 第四節 小結 第六章 結論 參考書目

In the thesis work we investigate four problems connected with dynamical processes in condensed medium, using different techniques of equilibrium and non-equilibrium statistical mechanics. Biology is rich in dynamical events ranging from processes involving single molecule [1] to collective phenomena [2]. In cell biology, translocation and transport processes of biological molecules constitute an important class of dynamical phenomena occurring in condensed phase. Examples include protein transport through membrane channels, gene transfer between bacteria, injection of DNA from virus head to the host cell, protein transport thorough the nuclear pores etc. We present a theoretical description of the problem of protein transport across the nuclear pore complex [3]. These nuclear pore complexes (NPCs) [4] are very selective filters that monitor the transport between the cytoplasm and the nucleoplasm. Two models have been suggested for the plug of the NPC. The first suggests that the plug is a reversible hydrogel while the other suggests that it is a polymer brush. In the thesis, we propose a model for the transport of a protein through the plug, which is treated as elastic continuum, which is general enough to cover both the models. The protein stretches the plug and creates a local deformation, which together with the protein is referred to as the bubble. The relevant coordinate describing the transport is the center of the bubble. We write down an expression for the energy of the system, which is used to analyze the motion. It shows that the bubble executes a random walk, within the gel. We find that for faster relaxation of the gel, the diffusion of the bubble is greater. Further, on adopting the same kind of free energy for the brush too, one finds that though the energy cost for the entry of the particle is small but the diffusion coefficient is much lower and hence, explanation of the rapid diffusion of the particle across the nuclear pore complex is easier within the gel model. In chemical physics, processes occurring in condensed phases like liquid or solid often involve barrier crossing. Simplest possible description of rate for such barrier crossing phenomena is given by the transition state theory [5]. One can go one step further by introducing the effect of the environment by incorporating phenomenological friction as is done in Kramer’s theory [6]. The “method of reactive flux” [7, 8] in chemical physics allows one to calculate the time dependent rate constant for a process involving large barrier by expressing the rate as an ensemble average of an infinite number of trajectories starting at the barrier top and ending on the product side at a specified later time. We compute the time dependent transmission coefficient using this method for a structureless particle surmounting a one dimensional inverted parabolic barrier. The work shows an elegant way of combining the traditional system plus reservoir model [9] and the method of reactive flux [7] and the normal mode analysis approach by Pollak [10] to calculate the time dependent transmission coefficient [11]. As expected our formula for the time dependent rate constant becomes equal to the transition state rate constant when one takes the zero time limit. Similarly Kramers rate constant is obtained by taking infinite time limit. Finally we conclude by noting that the method of analyzing the coupled Hamiltonian, introduced by Pollak is very powerful and it enables us to obtain analytical expressions for the time dependent reaction rate in case of Ohmic dissipation, even in underdamped case. The theory of first passage time [12] is one of the most important topics of research in chemical physics. As a model problem we consider a particle executing Brownian motion in full phase space with an absorbing boundary condition at a point in the position space we derive a very general expression of the survival probability and the first passage time distribution, irrespective of the statistical nature of the dynamics. Also using the prescription adopted elsewhere [13] we define a bound to the actual survival probability and an approximate first passage time distribution which are expressed in terms of the position-position, velocity-velocity and position-velocity variances. Knowledge of these variances enables one to compute the survival probability and consequently the first passage distribution function. We compute both the quantities for gaussian Markovian process and also for non-Markovian dynamics. Our analysis shows that the survival probability decays exponentially at the long time, irrespective of the nature of the dynamics with an exponent equal to the transition state rate constant [14]. Although the field of equilibrium thermodynamics and equilibrium statistical mechanics are well explored, there existed almost no theory for systems arbitrarily far from equilibrium until the advent of fluctuation theorems (FTs)[15] in mid 90�s. In general, these fluctuation theorems have provided a general prescription on energy exchanges that take place between a system and its surroundings under general nonequilibrium conditions and explain how macroscopic irreversibility appears naturally in systems that obey time reversible microscopic dynamics. Based on a Hamiltonian description we present a rigorous derivation [16] of the transient state work fluctuation theorem and the Jarzynski equality [17] for a classical harmonic oscillator linearly coupled to a harmonic heat bath, which is dragged by an external agent. Coupling with the bath makes the dynamics dissipative. Since we do not assume anything about the spectral nature of the harmonic bath the derivation is valid for a general non-Ohmic bath.

Despite numerous advances in experimental methodologies capable of addressing the various phenomenon occurring on metal surfaces, atomic scale resolution of the microscopic dynamics remains elusive for most systems. Computational models of the processes may serve as an alternative tool to fill this void. To this end, parallel molecular dynamics simulations of self-diffusion on metal surfaces have been developed and employed to address microscopic details of the system. However these simulations are not without their limitations and prove to be computationally impractical for a variety of chemically relevant systems, particularly for diffusive events occurring in the low temperature regime. To circumvent this difficulty, a corresponding coarse-grained representation of the surface is also developed resulting in a reduction of the required computational effort by several orders of magnitude, and this description becomes all the more advantageous with increasing system size and complexity. This representation provides a convenient framework to address fundamental aspects of diffusion in nonequilibrium environments and an interesting mechanism for directing diffusive motion along the surface is explored. In the ensuing discussion, additional topics including transition state theory in noisy systems and the construction of a checking function for protein structure validation are outlined. For decades the former has served as a cornerstone for estimates of chemical reaction rates. However, in complex environments transition state theory most always provides only an upper bound for the true rate. An alternative approach is described that may alleviate some of the difficulties associated with this problem. Finally, one of the grand challenges facing the computational sciences is to develop methods capable of reconstructing protein structure based solely on readily-available sequence information. Herein a checking function is developed that may prove useful for addressing whether a particular proposed structure is a viable possibility.

British accession to the European Union (EU) had far reaching economic, political and social consequences for New Zealand, forcing New Zealand to transform itself from a dependent subsidiary of Britain to acting as an independent small state for the first time. Although still in its infancy, the contemporary relationship New Zealand has formed with the EU is quite different to that it first established in the 1970s. It has increasing become more institutionalised, with a slowly developing structural framework that facilitates the narrow areas of cooperation. Dominated by the important economic relationship, the main challenges faced are of an economic nature. But the relationship also encompasses areas of political and social cooperation including people-to-people links, the environment, educational linkages, mutual support for multilateral institutions and development in the Pacific. As a small state, New Zealand is expected to display certain foreign policy behaviours in its interaction with bilateral partners. Small state theory forms the theoretical framework that explains New Zealand's behaviour in its foreign policy interaction with the EU. The theory was chosen for both its perceived usefulness in explaining and understanding the foreign policy behaviour of small states and for the apparent weaknesses of the theory, which is revealed in the case study of New Zealand-EU relations. This demonstrates how the theory is useful for its explanation of small state foreign policy behaviour, but also providing an insightful revelation of the theories flaws. This thesis proposes modifications to small state theory in order to strengthen it, and make it more encompassing of the contemporary realities of small state foreign policy, demonstrating that size does matter when exercising a foreign policy.

Orientador: Sergio Persio Ravagnani / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-07T03:49:14Z (GMT). No. of bitstreams: 1 Trochmann_JoseLuizLino_D.pdf: 1070584 bytes, checksum: 3407aee7ad6d88d9de0a1326aaf3d29d (MD5) Previous issue date: 2006 / Resumo: Neste trabalho de tese foi realizado um estudo do potencial de predição de propriedades de transporte em matrizes poliméricas de poli - imidas, utilizando a simulação dinâmica molecular de gases simples como Oxigênio, Nitrogênio e Dióxido de Carbono. A propriedade de transporte de interesse prático, a permeabilidade de uma membrana polimérica a um dado penetrante, envolve a determinação de propriedades de ordem cinética e termodinâmica, respectivamente a determinação do coeficiente de difusão e da solubilidade deste penetrante na matriz polimérica. Atenção especial foi conferida à propriedade cinética, pela predição do coeficiente de autodifusão dos penetrantes. Num procedimento experimental clássico é de vital importância para significância das conclusões derivadas dos experimentos, o uso de amostras de membranas poliméricas adequadamente preparadas quanto à composição química, estrutura física e morfologia. Analogamente, quando se utiliza a simulação molecular para a predição de propriedades, tais como o coeficiente de autodifusão, também é de fundamental relevância para os resultados obtidos, a qualidade dos modelos moleculares das matrizes poliméricas, que serão usados como base. Assim para a preparação de modelos moleculares com o adequado empacotamento, um procedimento para a obtenção de modelos bem equilibrados foi desenvolvido neste trabalho. Os modelos moleculares desenvolvidos foram usados para a obtenção dos valores de massa específica em função da temperatura, e comparados aos valores experimentais disponíveis e quando necessário a, valores preditos por meio da expressão de massa específica em função da temperatura, acima e abaixo da temperatura de transição. A capacidade do modelo molecular desenvolvido em predizer a massa especifica e temperatura de transição vítrea foi usada como critério para a validação da adequação do empacotamento proposto para o referido modelo molecular da matriz polimérica. Os modelos validados de empacotamento, células amorfas, foram utilizados para o cálculo do coeficiente de autodifusão dos gases acima mencionados, através do da simulação dinâmica molecular. A comparação dos coeficientes de autodifusão obtidos das poli-imidas aromáticas e éster imidas, BAAF, 6FDA-ODA, PMDA-ODA e BA-20DA, para os gases O2, N2 e CO2, com os dados experimentais, permitiu concluir a adequação das células amorfas e do esquema de simulação dinâmica molecular para a predição do coeficiente de autodifusão.. A versão preditiva de Vrentas e Duda, baseada na teoria do volume livre, foi utilizada para a predição dos coeficientes de autodifusão da água e do etanol para as poli-imidas acima. , Estes valores, quando comparados com os valores obtidos através da simulação dinâmica molecular mostram a validade de ambas as teorias para a predição da cinética de difusão de penetrantes em matrizes poliméricas complexas / Abstract: In this thesis a study of the predictive potential of the molecular dynamic simulation was performed for transport properties of light gases in polyimide matrix. From de practical point of view permeability is the property of most interest, and involves kinetics as well as thermodynamics properties, diffusion coefficient and solubility of the penetrants molecule in the bulk polymeric matrix, this work will be focus in the former. As important as is in as experimental work, a well prepared polymeric membrane is essential for the significance of the draw conclusions. Therefore a special attention was take in the preparation of the bulk molecular polymeric model, the so called amorphous cell, in order to obtain well-equilibrated molecular packing models for the polyimide matrixes. The amorphous cells were prepared throughout thermodynamic transforms, using one or more of the statistical ensembles and cell specific volume obtained as a function of temperature, this data was compared against the experimental data available, and when necessary to data obtained via predictive methods. The molecular packing model ability to predict the glass transition temperature was used as criteria to validate de amorphous cell, to be used in the molecular dynamic' simulations allow the matrix to be locally flexible and coupled to the classic molecular dynamics simulation. The resulting self diffusion coefficients for the polyimide, BAAF, 6FDA-ODA, PMDA­ODA and BA-20DA for the gases O2, N2 e CO2 were compared to the experimental data. The lack of quality experimental diffusion data available for polyimide membranes for larger penetrants as water and ethanol, showed up as a good opportunity to assess the predictive capability of the molecular dynamic simulation for self diffusion coefficients, considering the relevant technological relevance of polyimide membranes for pervaporation process. The data of self diffusion coefficient produced by the predictive version of free-volume theory after Vrentas and Duda, was compared with the data produced via coupled molecular dynamic simulation for the water and ethanol penetrants, showing the relevance of both theories for the prediction of penetrants kinetic in complex polymeric matrixes / Doutorado / Ciencia e Tecnologia de Materiais / Doutor em Engenharia Química

A time-delayed response of individual living organisms to information exchanged within flocks or swarms leads to the emergence of complex collective behaviors. A recent experimental setup by (Khadka et al 2018 Nat. Commun. 9 3864), employing synthetic microswimmers, allows to emulate and study such behavior in a controlled way, in the lab. Motivated by these experiments, we study a system of N Brownian particles interacting via a retarded harmonic interaction. For N 3 , we characterize its collective behavior analytically, by solving the pertinent stochastic delay-differential equations, and for N>3 by Brownian dynamics simulations. The particles form molecule-like non-equilibrium structures which become unstable with increasing number of particles, delay time, and interaction strength. We evaluate the entropy and information fluxes maintaining these structures and, to quantitatively characterize their stability, develop an approximate time-dependent transition-state theory to characterize transitions between different isomers of the molecules. For completeness, we include a comprehensive discussion of the analytical solution procedure for systems of linear stochastic delay differential equations in finite dimension, and new results for covariance and time-correlation matrices

No description available.