The germanium–selenium phase diagram

1969 ◽  
Vol 47 (14) ◽  
pp. 2555-2559 ◽  
Author(s):  
L. Ross ◽  
M. Bourgon

The Ge–Se phase diagram was determined in the composition range 0–66.67 at. % Se by the method of differential thermal analysis. The diagram differs totally from the one reported by Liu etal. (1) but is in good agreement with the diagram recently reported by Karbanov etal. (13). In its broad features the Ge–Se phase diagram is quite similar to the diagrams of the Ge–S, Sn–S, and Sn–Se systems.

1971 ◽  
Vol 49 (8) ◽  
pp. 1315-1316 ◽  
Author(s):  
A. N. Campbell ◽  
W. H. W. Wood

The Ag–Ca system has been reinvestigated over the composition range 50–100 atomic % Ca, by differential thermal analysis and high temperature X-ray powder diffraction. Our results are in good agreement with those of Alexander et al. (1) and those of Pascal et al. (2) in the region 50–59 atomic % Ca, but the peritectic claimed by Alexander et al., lying at 50% Ca and 598 °C, appears not to exist, according to our DTA and X-ray results. Here and elsewhere our results substantiate those of Pascal et al. We also find that the compound AgCa3 is formed peritectically, and not congruently as suggested by Alexander et al.


Author(s):  
Dominika Jendrzejczyk-Handzlik ◽  
Piotr Handzlik

In this work, the ternary Ag-Au-Ga system was studied experimentally by differential thermal analysis (DTA). Measurements were carried out along two chosen cross-sections determined by the ratio of mole fractions XAg/XGa=1:1 and XAu/XGa=1:1 by applying Pegasus 404 apparatus form Netzsch. Experiments were performed at three rates: 1 K min-1, 5 K min-1 and 10 K min-1. Next, the obtained experimental results were used to estimate the temperatures of liquidus by applying extrapolation to zero rate. Moreover, the temperatures of invariant reactions and other phase transformations were investigated from DTA measurements which were carried out with the rate 1 K min-1. Finally, the experimental results were compared with the isopleths obtained from prediction and calculation of the phase diagram which were done by using CALPHAD method. Experimental data obtained in this work are in good agreement with the results of calculation.


2000 ◽  
Vol 55 (11-12) ◽  
pp. 895-898
Author(s):  
T. A. Mirnaya ◽  
V. V. Trachevski ◽  
V. S. Dradrakh ◽  
D. V. Bylina

Abstract Phase equilibria of non-mesogenic caesium- and zinc-butyrate mixtures were studied by differential thermal analysis and hot stage polarization microscopy. Smectic liquid crystals were found in some composition range. Their appearance is explained by the latent mesomorphism of caesium butyrate. |133Cs NMR spectra and the specific electrical conductivity of the molten mixtures at 155°C were employed to investigate the peculiarities of ionic association and interaction in the melts.


1967 ◽  
Vol 22 (8) ◽  
pp. 1177-1180 ◽  
Author(s):  
Bengt Augustsson ◽  
Arnold Kvist

Previously obtained conductivity and viscosity results for the system (Li,K)2SO4 with less than 3 mole% K2SO4 show bad agreement with the phase diagram given in the literature. From conductivity, viscosity and differential thermal analysis we have constructed a new phase diagram for these concentrations.


1994 ◽  
Vol 47 (9) ◽  
pp. 1651 ◽  
Author(s):  
R Sabbah ◽  
M Gouali

A thermodynamic study of the three nitrophenol isomers (general formula C6H5NO3) was realized by combustion calorimetry of small amounts of substance (a few milligrams), sublimation calorimetry, differential thermal analysis and heat capacity measurements. The experimental enthalpies of combustion, sublimation and fusion of these compounds are as follows: ortho para -ΔcH�m(s,298.15K)/kJ mol-1 2871.0�1.3 2875.1�0.9 2868.5�1.0 ΔsubH�m(298.15K)/kJ mol-1 72.30�0.28 91.23�0.49 92.39�0.43 ΔfusHm/kJ mol-1 18.32�0.35 20.54�0.34 17.33�0.10 Ttriple point/K 318.40�0.01 370.51�0.01 387.26�0.05   The strength of the intramolecular hydrogen bond in the ortho isomer was estimated equal to 20.09 kJ mol-1. The relative stability of the three isomers is discussed, and the intermolecular bond enthalpies have been determined. The experimental resonance energies Eexp,conj are 168.7, 142.8 and 148.2 kJ mol-1 for ortho -, meta- and para-nitrophenol respectively, and are in good agreement with theoretical values. The experimental atomization enthalpies Δa,expH°m(298.15K) are 6742.5�1.9, 6719.5�1.7 and 6724.9�1.8 kJ mol-1 for ortho -, meta- and para-nitrophenol respectively.


2013 ◽  
Vol 200 ◽  
pp. 50-53
Author(s):  
Inna A. Ivashchenko ◽  
Volodumur V. Halyan ◽  
Irina V. Danylyuk ◽  
Volodumur Z. Pankevuch ◽  
Georgij Y. Davydyuk ◽  
...  

The phase diagram of the Ga2Se3–In2Se3 system was investigated by differential-thermal analysis (DTA) and X-ray diffraction (XRD) method. The single crystals from the area of existence of the γ2 phase with the compositions (Ga0.6In0.4)2Se3 and (Ga0.594In0.396Er0.01)2Se3 were grown by a vertical Bridgman method. Absorption spectra of the grown crystals were studied. The estimated optical band gap is 1.95±0. 01 eV. The resistance of the single crystals of (Ga0.6In0.4)2Se3 (R=500 MΩ) and (Ga0.594In0.396Er0.01)2Se3 (R=210 MΩ) was measured.


1968 ◽  
Vol 46 (8) ◽  
pp. 1171-1174 ◽  
Author(s):  
J. E. Dutrizac ◽  
M. B. I. Janjua ◽  
J. M. Toguri

The quasi-reduced iron–selenium phase diagram has been determined by a combination of differential thermal analysis, visual polythermal, and liquid sampling techniques. Iron and selenium form two compounds: FeSe2 with a broad stoichiometry range and FeSe2 with a much narrower composition field. The former compound was found to melt congruently at 1070 °C and 53.5 atomic % selenium, while the latter melted incongruently at 585 °C. Two liquid–liquid regions were observed in this system. One occurred above 790 °C from 73.9 atomic % selenium to about 99.92% selenium with a consolute temperature of 1070 °C at approximately 93 atomic % selenium. The other liquid–liquid region extends upwards from 1520 °C and lies between 3 and 39.5 atomic % selenium.


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