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Abstract  

We report the theoretical analysis results of thermochemical properties of solvated Li+ ion in propylene carbonate (PC), which is one of the most popular solvents used in the lithium-ion battery composite. In the theoretical calculation, we employed the density functional theory method with the 6-31G basis set using the Gaussian03 package. It has been made clear that the solvation with four PC molecules around a Li+ ion is most favorable. Detailed results of the conventional quantum chemical analyses for these materials will also be presented. Thermochemical properties such as the standard (that is at 298.15 K and 101325 Pa) enthalpy, entropy, and Gibbs energy changes upon the formation of Li+ complexes solvated with PC molecules have been numerated and discussed. Furthermore, we will afford the features of desolvation of the solvated Li+ ion complexes when they interact with the carbon electrode modeled by ovalene molecules.

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Enthalpies of dissolution of benzo-15-crown-5 ether (B15C5) in mixtures of acetonitrile with water and in solutions of NaI and NaBPh4 (I=0.05 mol dm−3) in these mixtures were measured at 298.15 K. From the obtained results and appropriate literature data, the thermodynamic functions of B15C5/Na+ complex formation in acetonitrile-water mixtures were determined. The enthalpies of transfer of the complex B15C5/Na+ from pure acetonitrile to the examined mixtures were calculated and are discussed.

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Abstract  

A new magnesium borate Mg2[B2O4(OH)2]·H2O has been synthesized by the method of phase transformation of double salt at hydrothermal condition and characterized by XRD, IR, TG and DSC. The enthalpy of solution of Mg2[B2O4(OH)2]·H2O in 0.9764 mol L–1 HCl was determined. With the incorporation of the enthalpies of solution of H3BO3 in HCl (aq), of MgO in (HCl+H3BO3) (aq), and the standard molar enthalpies of formation of MgO(s), H3BO3(s), and H2O(l), the standard molar enthalpy of formation of –(3185.78±1.91) kJ mol–1 of Mg2[B2O4(OH)2]·H2O was obtained.

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Abstract  

The two complexes, [Ln(Ala)2(Im)(H2O)](ClO4)3 (Ln=Pr, Gd), were synthesized and characterized. Using a solution-reaction isoperibol calorimeter, standard enthalpies of reaction of two reactions: LnCl3⋅6H2O(s)+2Ala(s)+Im(s)+3NaClO4(s)=[Ln(Ala)2(Im)(H2O)](ClO4)3(s)+3NaCl(s)+5H2O(l) (Ln=Pr, Gd), at T=298.15 K, were determined to be (39.260.10) and (5.330.12) kJ mol–1 , respectively. Standard enthalpies of formation of the two complexes at T=298.15 K, Δf H Θ m {[Ln(Ala)2(Im)(H2O)](ClO4)3(s)} (Ln=Pr, Gd), were calculated as –(2424.23.3) and –(2443.43.3) kJ mol–1 , respectively.

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Abstract  

A novel calorimetric approach to the energetics of redox reactions in non-stoichiometric oxides is presented. The method utilizes a step-wise heated adiabatic calorimeter for determination of average enthalpies of oxidation. The measurement uncertainty is dominated by the uncertainty in the determination of the mass increment due to the oxidation. An experimental investigation of the re-oxidation energetics of reduced La1–yCayCrO3– is presented. The variation of the average formal oxidation state with temperature and oxygen fugacity is calculated from the experimentally determined enthalpy of oxidation and an estimated (lattice and configurational) entropy of oxidation. The calculated curves are in good agreement with experimental determinations reported in literature.

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Abstract  

Some specific features of the thermochemistry of epoxy-amine curing at the later stages of the reaction are considered. Possible mechanism of cross-linking and the question about the driving force leading to the infinite network are discussed. The coupling of the reaction kinetics and rearrangement of the chains crosslinked into the rigid supramolecular structure is the essential feature of epoxy-amine vitrified system. It has been proposed that owing to the contribution from the side process, different curing temperatures can result in the structures with different T g. It was also established that reaction of epoxy ring opening alone is not responsible for the residual curing. The latter is the result of the side processes. As compared with the reaction of epoxy ring opening the side processes are strongly dependent on the geometrical aspects.

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Studies of thermokinetics in an adiabatic calorimeter

I. Design and testing of an adiabatic automatic calorimeter

Journal of Thermal Analysis and Calorimetry
Authors: S. Zhan, J. Liu, Z. Qin, and Y. Deng

Abstract  

An adiabatic calorimeter in which automation of the control of the adiabatic condition and the thermogram recording is achieved in a simple way has been designed for studies of both thermochemistry and thermokinetics. A new method for specific heat measurements has been proposed and specific heats ofn-heptane were measured to test the reliability of this calorimeter.

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Abstract  

Isothermal calorimetry and UV-visible spectrophotometry have been used to study the thermochemistry of the enzyme-catalyzed hydrolysis of hydrophobic L-amino acid esters in organic solvents with low water content at 298 K. The p-nitrophenyl esters of Z-L-tyrosine and Z-L-phenylalanine were used as model hydrophobic substrates. Acetonitrile was used as a model organic solvent. A special preparation protocol of the reactants in the calorimetric vessel was applied in order to determine the heat effects accompanying the enzyme-catalyzed hydrolysis reaction in organic mixtures with low water content and the Tris buffer ionization enthalpies over the whole range of water content in acetonitrile. It was found that the molar enthalpy of the hydrolysis of p-nitrophenyl esters and buffer ionization enthalpy depend significantly and similarly on the water content in acetonitrile. However, the reaction enthalpy corrected for the buffer ionization enthalpy does not depend on the water content in organic solvent mixtures. An explanation of the effect of the selected organic solvent on the thermochemical parameters was provided on the basis of the IR spectroscopic data for the hydrogen bond network of water in acetonitrile. The results obtained show that the state of water in organic solvents is an important factor that determines the reaction enthalpy as well as buffer ionization enthalpy.

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Abstract  

Prof. Wojciech Zielenkiewicz was born in Warsaw on 6 June 1933. He studied chemistry at the Warsaw University and graduated in 1955. His master thesis in the field of nuclear chemistry dealt with the enrichment of bromobenzene by the Szilard-Chalmers method. Since 1955 his professional career has mostly been related to the Institute of Physical Chemistry of the Polish Academy of Sciences (PAS) founded in the same year. Initially, Wojciech Zielenkiewicz worked under the supervision of Prof. Wojciech Świętosławski. This cooperation had a powerful influence on Zielenkiewicz both as a researcher and as a person. His strong interest in thermochemistry at that time resulted partly from his research interest and partly from his attraction to one of the students doing her diploma who later became his wife. Zielenkiewicz’s PhD thesis carried out under Świętosławski’s supervision concerned the thermochemistry of cement hydration. For the purposes of this work, Zielenkiewicz constructed his first calorimeter – a labyrinth flow calorimeter which was a modified version of the first such calorimeter constructed by Świętosławski and Malawski in 1935. The calorimeter was applied for the determination of the heat of cement hardening. After his PhD, Zielenkiewicz worked on several other calorimeters for the study of heat of cement hydration with the quasi-adiabatic method as well as on ‘conduction’ calorimeters for the examination of the first phase of cement hydration. This activity resulted in a monograph Calorimetry and Thermochemistry of Cement written in collaboration with T. Krupa and published in 1975. In the following years, his scientific interests were focused mostly on various aspects of the transfer of heat energy in time, i.e. thermokinetics. He constructed a number of calorimeters for this type of measurements and, together with his co-workers, elaborated new numerical methods of determination of thermokinetics. Those methods were assessed at international symposia on thermokinetics organised by Zielenkiewicz in cooperation with the French Association of Calorimetry and Thermal Analysis (AFCAT). In this period, he established regular cooperation with scientists from France, Spain, and the USA. Research on thermokinetics includes not only theoretical studies but also experimental works. Most of the experiments conducted at the Department of Calorimetry headed by Prof. Zielenkiewicz were connected with inclusion compounds, particularly Werner complexes as well as porfyrine derivatives. In the last twenty years, Zielenkiewicz conducted research in the scope of biomolecules. The study resulted in the determination of thermodynamic properties of over 60 derivatives of nucleic acid bases and the establishment of new correlations between enthalpic, volume, and structural properties of the compounds examined. His most recent interests concerned the study of enthalpic processes of protein salting. Zielenkiewicz’s long and intensive work in the field of calorimetry and thermokinetics has appeared in numerous books and publications presenting his research results. He is the author of 7 monographs, a number of chapters in a monograph and about 200 scientific publications. They include, among others, Analysis of Course of Heat Effect in n-n Calorimeters, Signal Processing of Calorimetric System, Dynamic Theory (later translated into Russian and published in Russia), Advances in Calorimetry and Thermochemistry, Theory of Calorimetry written together with E. Margas and published in 2002 by Kluwer and the most recent book, Calorimetry, published in 2005. Prof. Zielenkiewicz has also been active as a supervisor. He assisted and supported the realisation of 14 completed PhD theses of the employees at the Institute of Physical Chemistry and is supervising 3 more students of the Institute. Moreover, he has been involved in the realization of several more PhD theses both in Poland and abroad. For many years Prof. Zielenkiewicz combined his activity on research with research coordination. He managed the organizational units of the Polish Academy of Sciences as the Director General of the PAS and as a Deputy Scientific Secretary. For 6 years he was a Scientific Secretary of the Division of Mathematical, Physical and Chemical Sciences of PAS. In the years 1968–2003 he headed the Laboratory and Department of Calorimetry and he was a director of the Institute of Physical Chemistry for 19 years. His directorship in the Institute happened in a very difficult period for Poland, i.e. when the Marshall Law was introduced in 1981. As numerous employees of the Institute were involved in the illegal Solidarity movement at that time, the position of a director of such an institution was extremely uncomfortable and required great abilities in dealing with the communist authorities in such a way as to protect those employees. It must be said that Prof. Zielenkiewicz faced this challenge with success. Prof. Zielenkiewicz was also an initiator of the Polish conferences on calorimetry and thermal analysis. The first one was held over 30 years ago. These conferences created an opportunity for Polish researchers to exchange their opinions and learn about the world research trends. Numerous outstanding scientists were guests at these conferences. Many of them are members of the Polish Society of Calorimetry and Thermal Analysis. Prof. Zielenkiewicz has been awarded many state and foreign medals and distinctions, among others, Wojciech Świętosł;awski’s Medal and the Calvet Award given by the French Association of Calorimetry and Thermal Analysis (AFCAT) as well as the most prominent Polish state orders including the Order of Polonia Restituta (the Knight’s Cross) and the Order of Labour Banner. He is a corresponding member of the Polish Academy of Sciences and the Royal Academy of Sciences in Barcelona. Dr. Paweł Gierycz

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Abstract  

Calorimetry, Wojciech Zielenkiewicz Institute of Physical Chemistry of the Polish Academy of Sciences, 2005 ISBN: 83-920719-2-1 During the last few decades, there has been a rapid increase in research on as well as engineering in calorimetric systems, which become of wide use in modern material science. Sensor and chip technologies, instrumental and computerized systems of control and measurement have developed rapidly and the thermal properties of new materials, in particular thermokinetic effects and thermal stability has moved increasingly into the centre of interest. However, today’s knowledge in the calorimetry is distributed among vast number of highly specialized publications. Therefore a collection and summarization of this knowledge is certainly most welcome and thus this book furnishes scientists and engineers with a publication containing the state-of-the-art. The author has extensive experience and is probably one of the most knowledgeable scientists in the field of experimental and theoretical study related to thermochemistry and calorimetry, and has published intensively in the past on the subject of the book. Zielenkiewicz’s new book passes in review the applications of a wide range of calorimetric techniques, including modified versions and combinations thereof. The book contains 11 chapters, covering a wide field of topics related to thermophysical measurements, in particular determination of heat effects involved in various physical, chemical and biological processes, which is essential in molecular and supramolecular thermochemistry, in thermodynamic study of molecular interactions in liquid solutions, of the nature of bonds in alloys and polymers and in living organisms. Another field of interest is the industrial applications and biocalorimetric research on proteins. Chapter 1 provides an excellent outline of the history of calorimetry development. The first part of Chapter 2 presents a short overview on heat transfer. In the second part of the chapter the static-dynamic method for determination of heat effects in calorimeters are presented, restricted to fundamental knowledge alone. This chapter seems to be the most interesting one for scientists and practitioners using or developing thermal analysis devices. In Chapter 3, the analysis of heat effects courses occurring in the calorimeters as well as dynamic properties of calorimeters are discussed. Although Chapters 2 and 3 are written at a rather high physical and mathematical level, they contain only the absolutely necessary formulae. Chapter 4 gives an almost state-of-the-art overview of classification of calorimeters and methods for determination of heat effects. A short review of calibration and test reactions is also included. In Chapter 5, the adiabatic calorimeters are outlined. Chapter 6 is a guide for isoperibol, batch and nonadiabatic–nonisothermal calorimeters. Chapter 7 is a short review of calorimetric and indirect methods of determination of enthalpy of sublimation. It is an important chapter, but offers only a few points of contact with the rest of the book. Chapter 8 is devoted to detailed discussion of the batch, displacement and flow calorimeters. Chapter 9 discusses the conduction calorimeters, their possibilities and limitations. Sections on thermokinetic studies and determination of kinetic parameters are included. The presentation is very clear and straightforward, even of the fairly complicated theoretical derivations. Chapter 10 reports nonisothermal–nonadiabatic scanning devices, systematically analyses their applications to thermal analysis and gives a summary of the principles of DSC. Chapter 11 reviews briefly the pressure scanning calorimeters. The paragraph, although very short, is of special interest for the transistometry. Some of the chapters are excellent reviews of the literature while others are largely from the authors valuable own work. The necessary fundamental knowledge seems to be included almost completely even the special literature which can be found in the extensive list of references. The chapters of the book are correct presentations of the types of apparatus available, the methods of measurements and theories and applications associated with that part of the discipline under consideration. The book provides the reader with information about the development of calorimetry and its present day applications. Besides generally discussing the calorimetric techniques and the possibilities of their applications the book also elaborates the measurement of a wide variety of physico-chemical data (enthalpy of solution, dilution, mixing, sublimation, fusion, evaporation, adsorption, reaction, transformations, decomposition, polymerization; heat capacity, kinetic parameters, etc). In addition to detailed presentation of these measurements the book also describes special applications such as e.g., for studying liquid-crystal substances, biopolymers and photo-thermoelastic-acoustic phenomena. The author also pays attention to techniques that are seldom found in other books. The interested reader will profit by reading it and is guided through the essentials of this special, though important field which will rarely be found in normal books on thermal analysis. Therefore this book is a stop-gap work and exposes both the experts and the scientists, who are not familiar with calorimetric methods, to this knowledge. The text is well-written and readable with only few errors. Symbols and definitions are consistent between chapters, but not always follow the IUPAC recommendations. The nomenclature is correct. The figures in the book are helpful and the figure quality is variable but appropriate in spite of the various origins. However, the book lacks for an explanatory list of symbols and subject index. In summary, this book represents an excellent discussion of the theory and practice of calorimetry, will help to further an understanding of the various facets of the technique and should promote its application to new problems. The book contains much useful information, serves a useful purpose as a reference publication. It is wholeheartedly recommended reading for both the experienced scientists and the newcomers. Hopefully, the book under review will used as a frequently consulted work by everybody involved in the use of calorimeters. Dr. Andrs Dallos University of Veszprm, Hungary

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