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The work demonstrates a proof of application of the modulated-temperature dilatometry (MTDIL) to the stresses investigations of the well known and commonly used hard coatings e.g. TiN, TiCN, TiAlN thin films deposited mainly on different type of tools for its higher performances. In the PVD (physical vapour deposition) processes such kind of coatings are formed in meta stable state caused, between other, by strong stresses between coating and substrate. These stresses have an important influence on the fundamental properties of the coatings, for example, adherence to the substrate, so they are the subject of many investigations by use of different methods, mainly XRD (X-ray diffraction). For the purpose of presentation of application of MTDIL for such kind of investigation two reference substrate materials were chosen: ARMCO steel and cemented carbide in the form suitable for dilatometric analysis covered, by actually the most conventional, TiN hard coating. In the article the experimental results are presented, discussed and compared with simple model formed by means of finite elements method (FEM). [ABSTRACT FROM AUTHOR]

It has been determined the thermal behaviour at high temperatures of an iron aluminum arsenate mineral first described in the location of La Serena Valley, Extremadura, Spain, which expands until 1173 K contracting later and softening at 1653 K and full melting at 1773 K. The DTA/TG experiment only detects some rearrangement with an endothermic at 1173 K due to the mica mixing. The mineral is a scorodite variety mixed with micaceous clay which has been found as aggregates of pyramidal crystals associated with quartz, wolframite, molibdenite, cassiterite and other secondary minerals in the pegmatite of the San Nicolas mine. The chemical composition, the physico- chemical characteristics such as density and hardness, as well as the thermal behaviour has allowed to conclude that this mineral can be an Al-enriched scorodite (mansfieldite): (Fe, Al) AsO4·2H2O mixed with illite from the scorodite-mansfieldite series. [ABSTRACT FROM AUTHOR]

In this paper, several small-scale screening test methods were discussed on evaluating the thermal hazard of reactive substances. Generally the sensitivities of DSC and ARC are not high enough to evaluate the thermal hazards for all reactive substance, especially, for those of complex reactions containing a phase and/or chemical reaction mechanism change in the lower temperature range. Using the C80, however, the reaction can easily be detected in the lower temperature range due to its high sensitivity. Therefore, the C80 gives generally more accurate results than DSC and ARC. Data from C80 and Dewar vessel were compared and it indicates that the Dewar vessel has also high enough sensitivity to evaluate the thermal hazard and determine the heat flux in lower temperature range of reactive substances. [ABSTRACT FROM AUTHOR]

In this paper, fundamentals of the isoconversional methods are summarized and the methods are analyzed from the point of view of their correctness, their applications and the physical meaning of the activation parameters obtained. It is concluded that the activation parameters represent apparent quantities without a mechanistic interpretation. The parameters cannot be used for any theoretical considerations; however, they enable modelling the processes for other temperature regimes than those applied in the measurements. The differential and incremental isoconversional methods give the actual values of activation parameters whereas the isothermal and integral isoconversional methods provide the averaged values. For the modelling, the activation parameters obtained from the treatment of non-transformed kinetic data should be used. [ABSTRACT FROM AUTHOR]

This work aims in studying the temperature dependence of the thermal properties (thermal diffusivity, k, specific heat, Cp and thermal conductivity, λ) of some basalt group samples, collected from different regions in the eastern desert of Egypt. The thermal properties of these samples were measured in the temperature range from r.t. to 900 K. The average values of the thermal conductivity of these investigated samples lie in the range from 0.4· 10-3 to 2.01 · 10-3 cal cm-1 s-1 K-1. This means that these samples are considered as thermal insulating materials. The thermogravimetric analysis (TG) confirmed that these investigated samples are dry rocks. X-ray fluorescence (XRF) and X-ray diffraction (XRD) confirmed that these rock samples have a crystalline phase, the peaks of XRD have a small change in their location as a result of heat treatment. This behaviour was attributed to the oxidation and firing of some minerals after the heat treatment. [ABSTRACT FROM AUTHOR]

This paper reports an investigation of thermal and spectral properties of the complexes Cu2(3,5-Cl2sal)4·H2O (I), Cu(3,5-Br2sal)2·2H2O (II), Cu(3,5-I2sal)2·2H2O (III) and Cu(5-Isal)2·2H2O (IV), (where sal=salicylate). TG, DTG, DTA, IR, EPR and electronic spectra have been applied to investigate thermal and spectral properties of these complexes. The chemical composition of the complexes has been identified by means of elemental analysis and complexometric titration. Schemes of destruction of these complexes are suggested. Heating of these compounds first resulted in a release of water molecules. The thermal stability of these complexes can be ordered in the sequence: IV=I

After mechanochemical treatment of multicomponent mixtures complex fertilizers containing nitrogen, phosphorous, potassium and sulphur (NPKS) with higher water capacity were obtained. As raw materials some solid wastes and ammonia and potassium sulfates were used. Due to the different ratio used, new solid phases in the mixtures are formed. New solid phases are confirmed by the stages and rate of mass changes and also by the thermal effects at different temperature ranges. New phases are also confirmed by using X-ray diffraction method. On the base of data obtained mechanism of chemical transformations is proposed. It was found that the kinetics of mechanical activated mixtures decomposition is significantly influenced by the time of treatment and proceeds in few stages. The results have shown that the soluble nutrients forms ratio and sorption capacity could be controlled by the initial components ratios and treatment conditions. [ABSTRACT FROM AUTHOR]

Complexes of the general formulae Mn(2-bpy)2(CCl3COO)2, Co(2-bpy)2(CCl3COO)2·H2O and Ni(2-bpy)2(CCl3COO)2·2H2O (where: 2-bpy=2,2'-bipyridine) have been prepared and characterized by VIS and IR spectroscopy, conductivity and magnetic measurements. The thermal properties of complexes in the solid state were studied under non-isothermal conditions in air atmosphere. During heating the complexes decompose via different intermediate products to the oxides Mn3O4, CoO and NiO. A coupled TG-MS system was used to detection the principal volatile products of thermal decomposition and fragmentation processes of obtained compounds. The principal volatile products of thermal decomposition of complexes are: H2O+, CO2+, Cl2+ and other. [ABSTRACT FROM AUTHOR]

Aim of this work was to investigate the solid-state characteristics of micronized acetylsalicylic acid (ASA), produced by rapid expansion of a supercritical carbon dioxide solution (RESS) and to assess whether a correlation could be found between process parameters and solid-state characteristics. Drug solubility in supercritical CO2 was first assessed under various pressure and temperature conditions. DSC, FT-IR, PXRD, SEM, laser light scattering and HPLC were used to characterise the solid phases produced by the RESS. The obtained particles were crystalline, with spectroscopical and diffractometrical pattern overlapping those of the starting available product. However, a strong reduction of particle size was obtained, linearly correlated to pressure imposed during the RESS process, while temperature did not seem to have a major effect. Similar influence of pressure was observed on the final melting temperature of the micronized ASA. The application of a mathematical model allowed to conclude that the melting temperature depression of RESS-prepared ASA powders can be attributed to the decrease of particle dimension rather than to the formation of different solid phases or impurities. [ABSTRACT FROM AUTHOR]

The dehydration and decomposition of the red mud from Seydięehir Aluminum factory, mixed with soda were investigated under dynamic and isothermal conditions. Soda was added to the red mud samples as much as 50, 100 and 150 mass% of Na2CO3 of the red mud sample's mass. To determine the effect of soda additive on the red mud's thermal properties, using TG and DTA techniques simultaneously under atmospheric conditions. Furthermore, the original red mud sample's XRD and IR spectrum curves were investigated. It seems that the temperatures of the endothermic peaks of the red mud decreased with the amount of soda added. However the endothermic peak's temperature readings showed that the melting of soda increased gradually with the quantity of soda used. [ABSTRACT FROM AUTHOR]

Inverse numerical techniques have been applied in a range of different thermal studies in the past. These techniques require measurements of boundary conditions and temperatures at known position within the sample in order to determine thermal properties of the material of interest. Typically, they have been applied to highly specific applications and designs. In the current work the authors have designed a novel instrument in order to measure apparent specific heats of a range of different materials during continuous heating. Measurements of surface heat flux, surface and centre temperatures of the sample were obtained under controlled heating for temperatures of up to 1000°C. Measured data was used to quantify specific and latent heats by employing inverse numerical modelling technique. The instrument was calibrated with calorimetric calibration materials and results were compared with the literature values. The average experimental error was estimated to be approximately 0.9% for the reaction peak temperatures and 1.7% for the latent heats. Detailed experimental and calculation procedures as well as measured results of specific heat and enthalpy for a number of materials are presented here. [ABSTRACT FROM AUTHOR]

Sample controlled thermal analysis techniques such as constant rate transformation analysis or stepwise isothermal analysis, where the transformation rate of the sample itself is used to control the experiment, are becoming increasingly important [1]. The measurements are normally carried out using changes in the sample mass, sample dimensions or in the evolved gas, as the property used to control the experiment, and enable reactions to be studied in greater detail than is possible using linear heating techniques. A new approach is described here where a thermomicroscopy system has been developed to enable the intensity of the light reflected or transmitted by the sample to be used as the controlling signal [2]. [ABSTRACT FROM AUTHOR]

The authors of the title paper (J Therm Anal Calorim 2012,110:873-878) report to have grown a dipeptide hydrochloride crystal namely glycyl- l-alanine hydrochloride by the slow evaporation of an aqueous solution containing stoichiometric amounts of l-alanine and glycine and an excess of hydrochloric acid. In this letter, we prove that no such dipeptide hydrochloride can be crystallized simply by mixing two amino acids in aqueous hydrochloric acid. [ABSTRACT FROM AUTHOR]

The myometrium is the main component in enlargement of uterus and plays essential role in labour contraction. Its physiologic and elastic state has a decisive role in the labour process. We have made the first attempt to find correlation between the thermal parameters of uterus and progress of gravidity. Significant differences were observed between cyclic, non-pregnant and postmenopausal state (0.69 and 0.98 J g−1 calorimetric enthalpy as well as 60.6 and 63.1°C for T m), as well as among the different gestational stages and complications. In case of twin pregnancy and dystocia we have found extremities: 0.37 and 1.34 J g−1 calorimetric enthalpies, with 62 and 61.6°C melting temperatures. DSC method seems to be promising tool to follow and understand different molecular changes in the myometrium during pregnancy and its complication of human labour. [ABSTRACT FROM AUTHOR]

The thermal behavior of the kidney, heart and liver of spontaneous hypertension rats (SHR) were studied by thermogravimetry (TG) and differential thermal analysis (DTA). SHR are, by far, the most widely used rat model in the study of heart diseases in mammals, because they develop chronic hypertension, which leads to heart failure during their lives. TG curves showed two steps for all samples: at 800°C less residues remained for an SHR kidney (4.0±1.8%) than for an SHR heart (6.9±0.4) and liver samples (7.5±1.9%). It probably happened due to the presence of inorganic substances such as iron, calcium, magnesium, potassium and sodium. DTA curves depicted three endothermic events for kidney (70, 120 and 310°C), heart (85, 250 and 300°C) and liver samples (70, 250 and 310°C), indicating protein denaturation, as well as protein degradation and fat degradation, respectively. TG/DTG/DTA profiles of organs samples showed peculiarities that permit correlation between them. These methods might serve as a simple alternative to investigations over these vital organs. [ABSTRACT FROM AUTHOR]

Vinylidene chloride polymers containing comonomer units capable of consuming evolved hydrogen chloride to expose good radical-scavenging sites might be expected to display greater thermal stability than similar polymers containing simple alkyl acrylates as comonomer. Incorporation of a comonomer containing the phenyl t-butyl carbonate moiety into a vinylidene chloride polymer has the potential to afford a polymer with pendant groups which might interact with hydrogen chloride to expose phenolic groups. Copolymers of vinylidene chloride with [4-( t-butoxycarbonyloxy)phenyl]methyl acrylate have been prepared, characterized, and subjected to thermal degradation. The degradation has been characterized by thermal and spectroscopic techniques. The degradation of vinylidene chloride/[4-( t-butoxycarbonyloxy)phenyl]methyl acrylate copolymers is much more facile than the same process for similar copolymers containing either [4-(isobutoxycarbonyloxy)phenyl]methyl acrylate or methyl acrylate, a simple alkyl acrylate, as comonomer. During copolymer degradation, [4-( t-butoxycarbonyloxy) phenylmethyl acrylate units are apparently converted to acrylic acid units by extensive fragmentation of the sidechain. Thus, the phenyl t-butyl carbonate moiety does function as a labile acid-sensitive pendant group but its decomposition in this instance leads to the generation of a phenoxybenzyl carboxylate capable of further fragmentation. [ABSTRACT FROM AUTHOR]

The thermal polymerization of styrene is a long-known and well-practiced phenomena. While the mechanism of the thermal initiation event has been the subject of several investigations, it is not yet well understood. In an attempt to gain further insight as to the details of possible initiation from styrene dimer, analogous stable cycloadducts (maleic anhydride, tetracyanoethylene) of 1- and 2-vinylnaphthalene have been synthesized, fully characterized spectroscopically, and subjected to thermal decomposition. In the main, the major thermal event observed for these styrene dimer mimics is retro cycloaddition. This process is characterized by an activation enthalpy of approximately 30 kcal mol–1. Aminor process which accompanies the major reaction is the homolysis of a carbon–hydrogen bond to generate a carbon radical which may be trapped as a stable adduct of the 2,2,6,6-tetramethylpiperinyloxy (TEMPO) radical. [ABSTRACT FROM AUTHOR]

{\rtf1\ansi\ansicpg1250\deff0\deflang1038\deflangfe1038\deftab708{\fonttbl{\f0\froman\fprq2\fcharset238{\*\fname Times New Roman;}Times New Roman CE;}} \viewkind4\uc1\pard\f0\fs20 New explanations are given for two types of irregular thermogravimetric (TG) data. A TG relationship between mass and temperature is derived on the basis of migration behavior of bubbles generated in bulk of sample system, and superposed on that derived on the basis of kinetics of the 4\super th\nosupersub order event, which is superposed on the experimental TG data obtained from three reference papers. This suggests that these TG data are reflecting migration of bubbles. A dependence of TG behavior on heating rate, which is contrary to usual that, is shown and is explained in terms of event-rate determination by boiling. \par } [ABSTRACT FROM AUTHOR]

This issue of Journal of Thermal Analysis and Calorimetry contains selected papers based on presentations in the field of thermal characteristics of advanced polymer systems presented at the 8th International Symposium on Polymers for Advanced Technologies (PAT 2005) held in Budapest, September 2005. Guest Editors [ABSTRACT FROM AUTHOR]