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Abstract  

Phase diagrams of urea-α-naphthol and urea-benzoic acid systems, determined by the thaw-melt method, show the formation of simple eutectic in each case. The growth velocity data, determined at different undercooling (ΔT) by observing the rate of movement of interface in a capillary, obey the Hillig-Turnbull equation, v=u(ΔT)n, where u and n are constants depending on the nature of the materials. Using enthalpy of fusion, undercooling (ΔT) and melting point data, entropy of fusion, interfacial energy, enthalpy of mixing, critical radius size and excess thermodynamic functions were calculated. The microstructural investigations give characteristic features of the eutectics.

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Summary By the information system of CoPalRed© and with the treatment of 63,543 bibliographical references of scientific articles, the field of surfactants has been analysed in the light of the Unified Scientometric Model. It was found that the distributions of actors (countries, centres, and research laboratories, journals, researchers, key words of documents) fit Zif's Unified Law better than the Zipf-Mandelbrot Law. The model showed an especially good fit for relational indicators such as density and centrality. Using the Unified Bradford Law, the three zones fit were: core, straight fraction, and Groos droop. The fractality index was used to verify that Science can present fractal as well as transfractal structures. In conclusion, the Unified Scientometric Model is, for its flexibility and its integrating capacity, an appropriate model for representing Science, joining non-relational with relational Scientometrics under the same paradigm.

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Abstract

The eutectic ternary phase diagrams of some typical volatilizable energetic materials have been investigated by high pressure differential scanning calorimeter (PDSC). The ternary HX phase diagrams for TNT/TNAZ/DNTF (TTD) and TNAZ/DNTF/RDX (TDR) systems were constructed by the correlation of the apparent fusion heat with the composition (HX method). And, the ternary TX phase diagrams (the temperature dependence on composition) for the two ternary systems were constructed by calculating from the data of the five TX binary phase diagrams. The eutectic compositions (mol%) of TTD and TDR ternary systems were obtained to be 52.3/27.3/20.4 (HX method), 53.2/25.8/21.0 (TX method) and 54.9/39.6/5.5 (HX method), 55.1/42.2/2.7 (TX method), respectively. The eutectic temperatures of the ternary systems were obtained by PDSC determination and TX method calculation to be 76.5 and 76.7 °C, 47.5 and 50.2 °C, respectively. It is shown that the results obtained by two methods are in agreement and the error in measuring or calculating eutectic compositions and temperatures for the two ternary systems are within allowable ranges of ±3 mol% and ±3 °C, respectively. Moreover, by means of constructing two ternary HX phase diagrams with different fixed composition of a component and comparing the apparent fusion heat of eutectics with calculated one, the results obtained from HX method for TTD system were proved. The results showed that the gasification or volatilization of easy volatile materials could be efficiently restrained by high pressure atmosphere, and the perfectly and ideally HX ternary phase diagrams can be constructed. In comparison with TX method, HX method has as a virtue of being quick and simple, especially on constructing ternary phase diagram.

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multidisciplinary with 1,106 papers (26% of all ESI papers from China), namely multidisciplinary chemistry and multidisciplinary materials and science, followed closely by physical chemistry with 407 (10%). Multidisciplinary chemistry ranked 1st from 2003 to 2008

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investigations of solution properties and phase equilibria involving solutions in general, and aqueous solutions in particular, have held prominent positions in (bio-)physical chemistry. The scientific insights gained thereby are invaluable, and besides

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Abstract  

This chapter of the Journal of Thermal Analysis and Calorimetry contains selected papers presented at the European Conference on Calorimetry and Thermal Analysis for Environment (ECCTAE 2005) organised by the Centre of Excellence TALES (Thermodynamic Laboratory for Environmental Purposes), Institute of Physical Chemistry of Polish Academy of Sciences and held under the auspices of Prof. Janusz Lipkowski, the Vice-President of the Polish Academy of Sciences (PAS). The Conference took place on September 6–11, 2005 in the Conference and Holiday Centre ‘Antałwka’ in Zakopane, Poland. In the past, the first International Conference on the Calorimetry and Thermodynamics was organized by the Institute of Physical Chemistry of PAS in 1969 in Warsaw. This conference was dedicated to Prof. Wojciech Świętosławski, the late outstanding thermodynamic scientist who died on April 29, 1968. He was one of the most prominent Polish physicochemist and the first director general of the Institute of Physical Chemistry of PAS, which had been founded in 1965. In effect of the successful performance of such conference, the Institute of Physical Chemistry organized later the four National Conferences on Calorimetry and Thermal Analysis in Zakopane from 1973 to 1988. The Organizing Chairman was Prof. Wojciech Zielenkiewicz, the Corresponding Member of the Polish Academy of Sciences, who also initiated to create the Polish Society of Calorimetry and Thermal Analysis (PTKAT) with the name of Prof. Wojciech Świętosławski. Later, from 1991 to 2003, the next five Conferences on Calorimetry and Thermal Analysis of the PTKAT was also organized in Zakopane by Prof. L. Stoch of the University of Science and Technology (AGH) of Krakow, by Prof. H. Piekarski of the University of Łdź, Prof. A. Małecki of the University of Science and Technology (AGH), and Prof. A. Książczak of the Warsaw University of Technology. In these organizations, the Institute of Physical Chemistry of PAS also participated. The aim of the Conference ECCTAE 2005 was to bring together all scientists interested in the calorimetry and thermal analysis applied for environmental purposes and came from the academy, universities, laboratories, industries, agencies, etc. Finally, 92 participants from eleven countries (Czech Republic, Germany, Hungary, Italy, France, Portugal, Romania, Russia, Sweden, United Kingdom, and Poland) took part in the Conference. The scientific program of the ECCTAE with 16 plenary lectures, 14 lectures and 53 posters reflected the most recent developments in the field of science and supplied many new results on environment and biochemistry, organic and inorganic. Calorimetry and thermal analysis play the major role in investigations on new materials for environment and biochemistry. New experimental techniques like solution, surfactant, combustion and hazard calorimetry, hazard thermal analysis, etc. are of the utmost importance. Finally, I would like to thank all the participants in the Conference and the authors for the careful preparation of their presentations and manuscripts in this special chapter of the Journal of Thermal Analysis and Calorimetry. I would also like to thank the best to all co-workers of the Organizing Committee. Hopefully, all of the participants from several countries enjoyed the wonderful days of this Conference in the beautiful place of Zakopane.

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A small number of publications are collected in this Special Chapter of the J. Therm. Anal. Cal. All these publications of the Special Chapter are related to scientific areas, which are presented and discussed at our International Conferences on Pharmacy and Applied Physical Chemistry. Of course, the publications collected here are only some typical highlights compared with the scientific program of the PhandTA 8, Monte Verit, 2004 with 50 oral contributions and 25 poster presentations. A rather complete overview of the scientific program was presented in J. Therm. Anal. Cal., 57, 1999. The latter volume represents a considerable part of the contributions given at the PhandTA 3, held in 1997 at the Centro Stefano Fanscini at Monte Verit, Ascona, Switzerland. The scientific program is the essential part of our Conferences, however, the conference site at Monte Verit is by its history, by the site on top of a hill situated in a wonderful park, overlooking Ascona and the Lago Maggiore a rather ideal place for the conferences of our anticipated quality. The PhandTA conferences were three times held at Monte Verit. The next one, the PhandTA 9 will be held on September 10 to 13, 2006 at the “Institut fr Pharmazeutische Technology und Biopharmazie”, University of Dsseldorf, Germany. The 10th anniversary, namely the PhandTA 10, will be held from Sunday 21st to Wednesday 24th of October, 2007. This anniversary meeting will also express our activities over a period of 15 years since the foundation of the European Society for Applied Physical Chemistry in 1992. With both of these Conferences we plan to create a Special Chapter in the JTAC. I extend on behave of the members of the board of eurostar-science an invitation to the members of our society and to our scientific friends to participate in the two forthcoming PhandTA’s. Additionally, all possible participants should consider a publication of the presented scientific work in cooperation with the members of the board and the editors of this journal. Cordially, Erwin E. Marti President of the European Society for Applied Physical Chemistry

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The scientometric study of the tendencies of change of basic chromatographic characteristics has been carried out based on the analysis of the content of papers published in this area in the following journals: Journal of Planar Chromatography — Modern TLC, Chromatographia, Journal of Chromatography A, Analytical Chemistry, Journal of Analytical Chemistry, Russian Journal of Physical Chemistry A, Sorption and Chromatographic Processes (Russia), as well as the abstracts of the articles published in CAMAG Bibliography Service (CBS). Based on the comparison of the contents of the articles on thin-layer chromatography (TLC) published in the recent two decades: (1) from 1980 to 1990 and (2) from 2000 to 2010, the estimate of the main analytical characteristics characterizing the method of planar chromatography has been carried out. The following characteristics of planar chromatography were taken as the most important ones for the above mentioned periods of time: methods of chromatography, a type of a chromatographic chamber, a variant of the plate used, a way of plate development, previous preparation of a chamber and a plate for development, a way of application of samples analyzed on a plate, composition of mobile phases used, etc. The results obtained are of interest for analytics, designers of chromatographic apparatus, physic chemists and other specialists working in the different areas of planar chromatography. Unfortunately, in the area of TLC the conditions of the experiment are described rather in detail in not more than in 20% of the articles.

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