This study explores experimental hydrogen sorption and desorption isotherms on LaNi4.3Fe0.7 at four temperatures, employing different statistical physics models based on the grand canonical ensemble. ...The choice of the most appropriate model considered statistical parameters and physical analysis of the estimated parameters, culminating in selecting the monolayer model with two types of energies. The detailed analysis of these parameters provides an improved understanding of the process, highlighting the presence of hysteresis in the H2sorption and desorption in the metallic alloy. The sorption and desorption energies determined for this model vary between 82 and 109 kJmol−1, indicating a predominant chemical mechanism. Calculations of thermodynamic potentials suggest that the processes are exothermic and spontaneous. When comparing with other alloys of the same base, we observed that adding Fe presents similar trends in the model parameters, contributing to subtle improvements in the process.
•H2 sorption and desorption isotherms on LaNi4.3Fe0.7 employing statistical physics.•The energies ranged from 82 to 109 kJ mol−1, indicating a chemical mechanism.•The simultaneous presence of Fe and Ni results in higher n1 and n2 values.•The Nasat values for each alloy tend to reduce with increasing temperature.
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•Insertion of chitosan between activated anthracite produced a new An/Ch adsorbent.•Cr(VI) and MO adsorption by An/Ch was investigated in single and binary systems.•Adsorption ...mechanism was evaluated via advanced statistical physics models.•An/Ch Active sites were more selective for MO than Cr(VI) in the adsorption systems.
A novel composite was prepared from chitosan and hydrogen peroxide–treated anthracite sheets and it was applied for the single and simultaneous adsorption of Cr(VI) and methyl orange (MO) at different temperature (25–45 °C) and pH (2–10). Experimental results showed that Cr(VI) as HCrO4− species was mainly removed by electrostatic interactions, while the reduced form Cr(III) was adsorbed via ion exchange and complexation reactions, thus concluding that Cr(VI) uptake was governed by adsorption–reduction coupled mechanism. Adsorption of MO on this composite was controlled by hydrogen bonding, n–π and also electrostatic attractions. Experimental data were fitted satisfactorily with Langmuir and Freundlich equations indicating that the composite was more selective for MO adsorption. Langmuir-based monolayer adsorption capacities (qmax) ranged from 188.01 to 201.77 mg/g for Cr (VI) and from 297.28 to 295.75 mg/g for MO in the single and binary systems, respectively, at 25 °C. Physicochemical parameters of statistical physics models were estimated and utilized to understand the adsorption mechanism of both adsorbates. A multi-docking and multi-molecular mechanisms could be present in the adsorption of Cr(VI) and MO, respectively. Density of receptor sites (NM) proved to be an essential factor that was associated to the adsorption capacities of the studied adsorbates and its values confirming the high selectivity of anthracite/chitosan active sites for MO uptake. The values of the adsorbed capacity ratio (Qb/Qs) revealed that MO enhanced uptake of Cr(VI) due to the newly formed active sites (i.e., synergism interaction), while MO adsorption was slightly decreased in the binary system at all temperatures reflecting a weak antagonism interaction. The adsorption energies corresponded to an exothermic process governed by physical forces for both pollutants.
This book offers a homogeneous presentation of the many faces of non-equilibrium thermodynamics. The first part is devoted to a description of the nowadays thermodynamic formalism recognized as the ...classical theory of non-equilibrium processes. This part of the book may serve as a basis to an introductory course dedicated to first-year graduate students in sciences and engineering. The classical description can however not be complete, as it rests on the hypothesis of local equilibrium. This has fostered the development of many theories going beyond local equilibrium and which cannot be put aside. The second part of the book is concerned with these different approaches, and will be of special interest for PhD students and researchers. For the sake of homogeneity, the authors have used the general structure and methods presented in the first part. Indeed, besides their differences, all these formalisms are not closed boxes but present some overlappings and parallelisms which are emphasized in this book. For pedagogical reasons, some problems have been analysed within the different formalisms to underline their differences and their convergences.
In Floquet engineering, periodic driving is used to realize novel phases of matter that are inaccessible in thermal equilibrium. For this purpose, the Floquet theory provides us a recipe for ...obtaining a static effective Hamiltonian. Although many existing works have treated closed systems, it is important to consider the effect of dissipation, which is ubiquitous in nature. Understanding the interplay of periodic driving and dissipation is a fundamental problem of nonequilibrium statistical physics that is receiving growing interest because of the fact that experimental advances have allowed us to engineer dissipation in a controllable manner. In this review, we give a detailed exposition on the formalism of quantum master equations for open Floquet systems and highlight recent work investigating whether equilibrium statistical mechanics applies to Floquet states.
This book is an introduction to the closely related subjects of quantum optics and quantum information. It gives a simple, self-contained introduction to both, while illustrating the physical ...principles of quantum information processing using quantum optical systems.
This book by Lev M. Blinov is ideal to guide researchers from their very first encounter with liquid crystals to the level where they can perform independent experiments on liquid crystals with a ...thorough understanding of their behaviour also in relation to the theoretical framework. Liquid crystals can be found everywhere around us. They are used in virtually every display device, whether it is for domestic appliances of for specialized technological instruments. Their finely tunable optical properties make them suitable also for thermo-sensing and laser technologies. There are many monographs written by prominent scholars on the subject of liquid crystals. The majority of them presents the subject in great depth, sometimes focussing on a particular research aspect, and in general they require a significant level of prior knowledge. In contrast, this books aims at an audience of advanced undergraduate and graduate students in physics, chemistry and materials science. The book consists of three parts: the first part, on structure, starts from the fundamental principles underlying the structure of liquid crystals, their rich phase behaviour and the methods used to study them, the second part, on physical properties, emphasizes the influence of anisotropy on all the aspects of liquid crystals behaviour, the third, focuses on electro-optics, the most important properties from the applications standpoint. This part covers only the main effects and illustrates the underlying principles is greater detail. Professor Lev M. Blinov has had a long carrier as an experimentalist. He made major contributions in the field of ferroelectric mesophases. In 1985 he received the USSR state prize for investigations of electro-optical effects in liquid crystals for spatial light modulators. In 1999 he was awarded the Frederiks medal of soviet Liquid Crystal Society and in 2000 he was honoured with the G. Gray silver medal of British Liquid Crystal Society. He has held many visiting academic positions in universities and laboratories across Europe and in Japan.
Energy exchange is a major foundation of the dynamics of physical systems, and, hence, in the study of complex multi-domain systems, methodologies that explicitly describe the topology of energy ...exchanges are instrumental in structuring the modeling and the computation of the system`s dynamics and its control. This book is the outcome of the European Project `Geoplex` (FP5 IST-2001-34166) that studied and extended such system modeling and control methodologies. This unique book starts from the basic concept of port-based modeling, and extends it to port-Hamiltonian systems. This generic paradigm is applied to various physical domains, showing its power and unifying flexibility for real multi-domain systems.
The assumption that quantum systems relax to a stationary state in the long-time limit underpins statistical physics and much of our intuitive understanding of scientific phenomena. For isolated ...systems this follows from the eigenstate thermalization hypothesis. When an environment is present the expectation is that all of phase space is explored, eventually leading to stationarity. Notable exceptions are decoherence-free subspaces that have important implications for quantum technologies and have so far only been studied for systems with a few degrees of freedom. Here we identify simple and generic conditions for dissipation to prevent a quantum many-body system from ever reaching a stationary state. We go beyond dissipative quantum state engineering approaches towards controllable long-time non-stationarity typically associated with macroscopic complex systems. This coherent and oscillatory evolution constitutes a dissipative version of a quantum time crystal. We discuss the possibility of engineering such complex dynamics with fermionic ultracold atoms in optical lattices.
Product design is characterized by a steady increase in complexity. The main focus of this book is a structural approach on complexity management. This means, system structures are considered in ...order to address the challenge of complexity in all aspects of product design. Structures arise from the complex dependencies of system elements. Thus, the identification of system structures provides access to the understanding of system behavior in practical applications. The book presents a methodology that enables the analysis, control and optimization of complex structures, and the applicability of domain-spanning problems. The methodology allows significant improvements on handling system complexity by creating improved system understanding on the one hand and optimizing product design that is robust for system adaptations on the other hand. Developers can thereby enhance project coordination and improve communication between team members and as a result shorten development time. The practical application of the methodology is described by means of two detailed examples.
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