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technique could be developed to replace metallography as the primary control tool [ 3 ]. Thermal analysis as a technique is used to evaluate the melt quality. By this method, some characteristic values are extracted from a cooling curve and/or its

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Abstract  

Mortars taken from the walls of three historical buildings in Seville: Pond of Patio de las Doncellas in Real Alcazar of Seville, the Monastery of Santa Maria de las Cuevas and the Church of El Salvador were investigated. The techniques employed were thermogravimetry (TG), differential thermal analysis (DTA), XRD, FTIR, SEM with EDAX, Bernard calcimeter, granulometry, mercury intrusion porosimetry and mechanical strength tests. The majority of the studied mortars consist of calcite and silica. Gypsum was detected in samples of four mortars from the Santa Maria de las Cuevas Monastery and two from the El Salvador Church, whose samples were taken from the upper layers of the walls, but gypsum was not detected in the internal mortars layers. Only in two of the samples of the Monastery, the presence of cellulosic material as an organic additive was detected. All the studied mortars could be regarded hydraulic, so much by results from ratios between mass loss due to CO2 and H2O, hydraulic module and assays of compressive strength. The values obtained by these three techniques are related, providing good agreements between them. These results give useful information that aids in understanding the technology of historic mortars, and how to plan the restoration of these wall paintings.

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Abstract  

Thermal properties of food systems are important in understanding relationships between food properties and changes in food quality. Concentrated food systems (low-moisture and frozen foods) are seldom in an equilibrium state and they tend to form amorphous, non-crystalline structures. Several glass transition-related changes in such foods affect stability, e.g., stickiness and caking of powders, crispness of snack foods and breakfast cereals, crystallisation of amorphous sugars, recrystallisation of gelatinised starch, ice formation and recrystallisation in frozen foods and rates of non-enzymatic browning and enzymatic reactions. Relationships between glass transition, water plasticisation and relaxation times can be shown in state diagrams. State diagrams are useful as stability or quality maps and in the control of rates of changes in food processing and storage.

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Thermal analysis of some polynuclear coordination compounds

Ligand tartarate, precursors of LnFeO3 perovskites

Journal of Thermal Analysis and Calorimetry
Authors: L. Patron, P. Budrugeac, A. Balu, Oana Carp, L. Diamandescu, and M. Feder

Abstract  

The thermal behaviour of five polynuclear coordination compounds containing tartaric anion as ligand, namely (NH4)3[LnFe(C4O6H4)3(OH)3] (Ln=La and Eu), (NH4)2[PrFe(C4O6H4)3(OH)2] and (NH4)[LnFe(C4O6H4)3(OH)]3H2O (Ln=Nd and Gd) was investigated. The reaction progress was studied by TG/DTA and FTIR measurements. Oxalates and oxocarbonates were identified as intermediates. In the case of Ln=La, Nd, Pr, Eu and Gd, pure LnFeO3 was obtained as final decomposition product. The thermal decomposition of Eu-Fe compound, leads to a mixture of mixed (ortho-ferrite (EuFeO3) and garnet (Eu3Fe5O12)) and simple oxides (Eu2O3 and α-Fe2O3).

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Micro-thermal analysis combines the imaging facility of scanning probe microscopy with the ability to characterize, with high spatial resolution, the thermal behavior of materials. A sample may be visualized according to its surface topography and also its relative thermal conductivity. Areas of interest may then be selected and localized thermal analysis (TMA and modulated temperature DTA) performed. Applications of this new technique to study semiconductors, polymer blends and biological specimens are described.

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remained elusive, as reflected by the large number of current methods used to describe it. The demand for a quantitative means to assess the complete SOM quality continuum, therefore, remains high [ 7 ]. While thermal analysis techniques have long

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This paper describes recent advances in thermal analysis instrumentation which combine the high resolution imaging capabilities of the atomic force microscope with physical characterisation by thermal analysis. Images of the surface may be obtained according to the specimen's thermal conductivity and thermal expansivity differences in addition to the usual topographic relief. Localised equivalents of modulated temperature differential scanning calorimetry, thermomechanical and dynamic mechanical analysis have been developed with a spatial resolution of a few micrometres. A form of localised thermogravimetry-evolved gas analysis has also been demonstrated. The same instrument configuration can be adapted to allow IR microspectrometry at a resolution better than the optical diffraction limit.

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Journal of Thermal Analysis and Calorimetry
Authors: M. Stenseng, A. Zolin, R. Cenni, F. Frandsen, A. Jensen, and K. Dam-Johansen

Abstract  

Thermal analysis is widely used in combustion research for both fundamental and practical investigations. Efficient combustion of solid fuels in power plants requires understanding of properties and behavior of fuel and ash under a wide range of conditions. At the Department of Chemical Engineering, Technical University of Denmark, thermogravimetric analysis and differential scanning calorimetry are applied in order to investigate various aspects of combustion and gasification processes: pyrolysis, char reactivity and ash melting behavior. This paper shows examples of the application of simultaneous thermal analysis in these three research areas, and it demonstrates the flexibility of this technique in combustion research.

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Thermal analysis on influence of compatibilizing agents

Effect of vulcanization of incompatible elastomer blend

Journal of Thermal Analysis and Calorimetry
Authors: K. Pandey, K. Debnath, P. Rajagopalan, D. Setua, and G. Mathur

Abstract  

Studies have been made on differential scanning calorimetry (DSC), thermogravimetric analysis (TG) and dynamic mechanical analysis (DMA) of binary blends of isobutylene-isoprene (IIR) copolymer and polychloroprene (CR) elastomers. Blends of IIR and CR are incompatible and showed separateT g peaks in DSC curves similar to Tanδ peaks. However, addition of chlorinated polyethylene (CM) elastomer, as compatibilizer, imparts miscibility between IIR and CR which could be judged both through DSC as well as by dynamic loss measurements (Loss modulusE″ and Tanδ). The storage modulus (E′) showed variation of stiffness due to structural changes associated with the addition of compatibilizer. TG plots for these blends showed improvement of thermal stability both by addition of a suitable compatibilizer as well as due to formation of crosslinked structures associated with the vulcanization of the blends by standard curative package.

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chemical analysis is prescribed, except for cases in which magnesium hydroxide is found by petrography or X-ray diffraction [ 3 ]. In the latter case, differential thermal analysis (DTA) or thermogravimetric (TG) analysis is used to quantify the amount of

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