Results 251 to 260 of about 74,950 (296)

DTA as a method of studying chemical reactions at high pressures

Thermochimica Acta, 1987
Abstract It is proposed that DTA should be used to study chemical reactions under high pressures “in situ”. Two techniques are described which allow the investigation of systems including substances of high chemical activity in different pressure ranges.
V.V. Avdeev, V.Z. Mordkovich
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Improved diagonal tensor approximation (DTA) and hybrid DTA/BCGS–FFT method for accurate simulation of 3D inhomogeneous objects in layered media

Waves in Random and Complex Media, 2007
This paper presents an improved diagonal tensor approximation (DTA) and its hybridization with the stabilized biconjugate-gradient fast Fourier transform (BCGS–FFT) algorithm to solve a volume integral equation for three-dimensional (3D) objects in layered media.
B. Wei, E. Ŝimŝek, Q. H. Liu
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Methods Combined with DTA

1974
Many crystalline substances show at distinct temperatures spontaneous, reversible structural transformations, the existence and temperatures of which can be observed very clearly in a DTA curve. However, the nature of the resulting products of reaction remains obscure, since these transformations receded during cooling.
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A new DTA method for measuring critical cooling rate for glass formation

Journal of Non-Crystalline Solids, 2005
A new differential thermal analysis (DTA) experimental method has been developed to determine the critical cooling rate for glass formation, R(sub c). The method, which is found especially suitable for melts that, upon cooling, have a small heat of crystallization or a very slow crystallization rate, has been verified using a 38Na2O-62SiO2 (mol%) melt ...
Chandra S. Ray, Signo T. Reis, Richard K. Brow, Wolfram Höland, Volker Rheinberger   +4 more
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Analysis of Alloys Using DTA and TD Methods with Simultaneous Thermomagnetic Studies

Journal of Thermal Analysis and Calorimetry, 1999
A modified thermoanalyzer for investigation ferromagnetic materials as metals and alloys is described. Conventional analog phase detection technique is replaced by specialized digital one which added some new outstanding features of the instrumentation.
P. Myśliński, P. Kamasa, J. Vandlik
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TG-DTA/FT-IR method for analyzing thermal decomposition mechanism of polyesters

Journal of Thermal Analysis, 1993
An attempt to estimate the thermal decomposition mechanism of polymers using the simultaneous TG-DTA/FT-IR system was summarized. The library search of FT-IR spectra at various temperatures and of the subtraction spectrum obtained by subtracting the spectra at different temperatures were used to determine the types of evolved gases from poly(ethylene ...
R. Kinoshita, Y. Teramoto, H. Yoshida
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STUDY OF CLATHRATE HYDRATION OF CARBOXYLIC ION EXCHANGER BY DTA METHOD

Solvent Extraction and Ion Exchange, 2000
ABSTRACT The effect of ionic composition [(C4H9) 4N-, H + (C4H9)N- and H-forms] and degree of swelling of a polyacrylic ion exchanger on the formation and stability of crystalline clathrate hydrates is studied. The melting temperature of clathrates for ion exchanger in the mixed ion form is to a large extent determined by the ratio of counter-ions. For
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The acidity of dealuminated clinoptilolite investigated by DSC, DTA and TG methods

Thermochimica Acta, 1992
Abstract Dealuminated NH 4 + -clinoptilolite samples, prepared using (NH 4 ) 2 SiF 6 and calcined at various temperatures, were used for the investigation of acidity properties. The strength of the acid sites was measured by a combination of TG and DSC measurements.
F. Grejták, I. Horváth, M. Kubranová, J. Krajčovič   +3 more
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Calorific Value Determination of Coals by DTA and ASTM Methods. Comparative study

Journal of Thermal Analysis and Calorimetry, 2001
This research comprises the applicability of complex thermal analysis technique (TG/DTG, DTA) in the determination of calorific values of coals of different origin. The calorific values, those obtained by thermal analysis are compared with an adiabatic bomb calorimeter by the standard ASTM method, and the results are discussed.
M. V. Kök, C. Keskin
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Use of kinetic DTA and TG methods for compatibility tests on 2,4,6‐‐trinitrotoluene

Propellants, Explosives, Pyrotechnics, 1986
AbstractWe have investigated the suitability of thermoanalytical methods for compatibility tests on explosives and contact materials. DTA and TG curves of various materials were evaluated using two DTA and four TG methods and one DSC method. TNT was used as model substance.
M. Hemmilä, I. Nieminen, A. Kariniemi, J. Valkonen   +3 more
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