- Phase equilibria in the Tl2Se-PbSe system and growth and properties of Tl4PbSe3 single crystals
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The T-x phase diagram of the Tl2Se-PbSe system has been mapped out. The system contains a congruently melting compound (803 K) of composition Tl4PbSe3, which forms a continuous series of solid solutions with Tl2
- Malakhovska-Rosokha,Sabov,Barchii,Peresh
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- Phase equilibria and thermodynamic properties of the system Tl-TlCl-Se
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Phase equilibria in the system Tl-Se-Cl were studied in the region Tl-TlCl-Se by DTA, X-ray powder diffraction, emf measurements concentration circuits (-) Tl/glycerol + KCl + TlCl/(Tl-Se-Ce) (+), and microhardness measurements. Several vertical sections,
- Babanly,Yusibov,Babanly
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- Phase diagrams of novel Tl4SnSe4-TlSbSe2-Tl2SnSe3 quasi-ternary system following DTA and X-ray diffraction
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Phase relation in the Tl4SnSe4-TlSbSe2-Tl2SnSe3 quasiternary system were studied by the DTA and X-ray diffraction in combination with mathematical modeling. The phase diagrams of the Tl4SnS
- Barchiy,Tatzkar,Fedorchuk,Plucinski
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- Phase equilibria and thermodynamic properties of the system Tl-TlBr-Se
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The system Tl-Se-Br was studied in the region Tl-TlBr-Se by DTA, X-ray powder diffraction, emf measurements, and microhardness measurements. Several vertical sections, the isothermal section at 400 K, and the liquidus-surface projection were constructed. The quasi-binary sections TlBr-Tl2Se, TlBr-TlSe, Tl5Se2Br-Tl, and Tl5Se 2Br-TlSe allow the system Tl-TlBr-Se to be triangulated into five subordinate triangles. Wide immiscibility regions were discovered in the system, including a three-phase region in subsystem Tl2Br-Tl 2Se-Se. Homogeneity and primary separation regions were determined, as well as the types and coordinates of invariant and monovariant equilibria on the T-x-y-diagram. From the results of emf measurements, the standard thermodynamic functions of formation were calculated for the compound Tl 5Se2Br. Nauka/Interperiodica 2007.
- Babanly,Yusibov,Babanly
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- The influence of the ionic component of the electrical conductivity on the semiconductor-metal transition in liquid Tl-Se alloys
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Experimental investigations of electrical conductivity σ(T) and thermo-e.m.f. S(T) were performed for liquid Tl-Se alloys in the region of the stoichiometric compound Tl2Se in a wide temperature range (from 600 K to 1700 K). It was shown that the existence of an ionic component in the electrical conductivity affects significantly the peculiarities of the metallization process of the liquid cells. A model explaining the unusual thermo-e.m.f. behavior, which forms a large deviation from the 'classical' dependence in a wide temperature range resulted from the effect of electron-hole compensation, has been proposed. The ionic contribution essentially changes the electrical conductivity resulting in a deformation of the exponential curve σ(T).
- Sklyarchuk,Plevachuk
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- Thermodynamic properties of ternary phases in the Cu-Tl-Se system
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The Cu-Tl-Se system has been studied at temperatures from 300 to 420 K using emf measurements with Cu4RbCl3I2 as a Cu+ ion conducting solid electrolyte. The emf data have been used to map out the subsolidus phase diagram of the Cu-Tl-Se system in the composition region Tl2Se-CuTlSe-CuSe-Se. We have calculated the partial molar thermodynamic functions of the copper in the alloys and the standard thermodynamic functions of formation and standard entropies of the ternary compounds CuTlSe2, CuTlSe, and Cu2TlSe2. The results confirm that the thermodynamic properties of copper-containing ternary systems can be studied using the approach in question even when they contain an element (thallium in this study) located to the left of copper in the electrochemical series.
- Babanly
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- Ag2Se-Tl2Se-Bi2Se3 quasi-ternary system
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The Ag2Se-Tl2Se-Bi2Se3 quasi-ternary system (system A) was studied using DTA, X-ray powder diffraction, microstructure examination, and microhardness measurements. TlBiSe 2-AgBiSe2, AgTlSe-
- Babanly,Aliev,Babanly
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- Phase equilibria in the Tl-TlI-Se system and thermodynamic properties of the ternary phases
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By using differential thermal analysis (DTA), X-ray analysis and electromotive force (EMF) methods the Tl-Se-I system was investigated in the Tl-TlI-Se composition range. Several polythermal sections, the isothermal section at 300 K and the projection of
- Babanly, Dunya M.,Amiraslanov, Imameddin R.,Shevelkov, Andrei V.,Tagiyev, Dilgam B.
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- Composition range and thermodynamic properties of Tl5Se 2Br-based solid solutions
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The equilibrium subsolidus phase diagram of the TlBr-Tl2Se-TlSe system has been mapped out using X-ray diffraction analysis and emf measurements on thallium concentration cells. Tl5Se2Br has been shown to have a broad homogeneity region. The emf results are used to evaluate the relative partial thermodynamic functions of the thallium in the alloys studied and the standard integral thermodynamic functions (ΔG 0(298 K), ΔH 0(298 K), S 0(298 K)) of the Tl 5Se2Br-based solid solutions.
- Babanly
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- Quasi-ternary system Tl2Se-AgTlSe-TlBiSe2
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The quasi-ternary system Tl2Se-AgTlSe-TlBiSe (A) has been investigated by DTA, X-ray powder diffraction, microstructural analysis, and microhardness measurements. Polythermal sections AgTlSe-TlBiSe2, AgTlSe-Tl9BiSe6, [Ag0.5Tl1.5Se]- TlBiSe2, Tl2Se-AgBiSe2 (0-50 mol % AgBiSe 2), an isothermal section at 500 K, and the projection of the liquidus surface of system A have been constructed. It has been shown that the quasi-binary join AgTlSe-Tl9BiSe6 divides system A into two subordinate triangles, namely, Tl2Se-Tl9BiSe 6-AgTlSe (B) and AgTlSe-Tl9BiSe6-TlBiSe 2 (C). The phase diagram of subsystem B involves a univariant eutectic equilibrium while subsystem C involves an invariant eutectic equilibrium. The ternary eutectic has the coordinates 650 K, 10 mol % TlBiSe2, and 61 mol % AgTlSe. A continuous series of solid solutions (0-12 mol % AgTlSe) has been found along the Tl2Se-Tl 9BiSe6 bordering system. The homogeneity region of TlBiSe2 extends to 5 mol %. Nauka/Interperiodica 2007.
- Babanly,Aliev,Azizov,Babanly
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- Phase studies on the quasi-binary thallium(I) selenide-cadmium selenide system
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The phase diagram for the quasi-binary Tl2Se-CdSe system has been established from the results of phase studies by common thermal analysis and X-ray diffraction. Numerical values for the phase transition temperatures at different alloy composit
- Mucha, Igor,Wiglusz, Katarzyna
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- Experimental investigation of the 3Tl2Se + Sb2Te 3 ? 3Tl2Te + Sb2Se3 phase diagram
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Phase equilibriums were established in the 3Tl2Se + Sb 2Te3 ? 3Tl2Te + Sb2Se 3 mutual system mainly by the X-ray powder diffraction and differential thermal analyses, with the aid of microhardness and EMF measurements applied to equilibrated alloys. According to the obtained experimental results the phase diagrams in form of the polythermal section and isothermal section at 300 K as well as the projection of the liquids surface have been constructed. It was found experimentally that the system is mutually reversible and is characterized by a wide solid solubility fields along the TlSbSe2-TlSbTe2 subsystem and within the Tl 2Se-Tl9SbSe6-Tl9SbTe 6-Tl2Te subsystem. The homogeneity and primary crystallization fields as well as the types and coordinates of non- and monovariant equilibriums were determined. The dependencies of crystallographic parameters, microhardness and EMF values upon the composition are discussed. From the EMF measurements, the partial molar functions of thallium (ΔG?,ΔH?,ΔS?) were calculated for the revealed nonstoichiometric quaternary phases.
- Jafarov, Yasin I.,Babanly, Mahammad B.,Shevelkov, Andrei V.,Aliev, Ziya S.
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p. 184 - 192
(2013/04/10)
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- Thermodynamic properties and homogeneity regions of Tl6SCl 4 and Tl5Se2Cl
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In this activity system Tl-Tl2X-X (X = S, Se)are studied using emf measurements of concentration chains relative thallic electrode. The solid phase diagrams of these systems are clarified, homogeneity areas of the compounds Tl6SClsu
- Guseinov,Babanly,Sadygov,Babanly
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p. 129 - 134
(2009/05/30)
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- Preparation, crystal structure, physical properties and electronic band structure of TlScQ2 (Q = S, Se and Te)
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The title compounds were prepared by reaction of Tl2Q (Q = S, Se and Te) Sc and Q in the temperature range of 200 to 500 °C. The structures of the selenide and the telluride adopt the α-NaFeO2 type, while TlScS2 crystallizes in the β-RbScO2 type structure. The space group is R3m for TlScSe2 and TlScTe 2 with a = 3.9370(4) A, c = 23.194(5) A, and a = 4.2129(4) A, c = 24.099(3) A, respectively. The sulphide crystallizes in P63/mmc with a = 3.761(3) A and c = 14.942(4) A. The crystal chemical relations between the three chalcogenides are discussed. According to the electrical measurements and the band structure calculations, the compounds are semiconductors or poor metals.
- Teske, Christoph L.,Bensch, Wolfgang,Mankovsky, Sergey,Ebert, Hubert
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p. 445 - 451
(2009/03/12)
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- System Tl4GeSe4-Tl2Se-Tl 4SnSe4
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Classical methods of physicochemical analysis with computer modeling were used to study phase equilibria in quasi-ternary system Tl4GeSe 4-Tl2Se-Tl4SnSe4 and to design its spatial phase diagram. Copyright
- Barchii,Glukh,Peresh,Tsigika
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p. 759 - 761
(2008/10/09)
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- The effect of KI on the formation of Tl2E (E = S, Se) nanorods via solvothermal route
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Tl2E (E=S or Se) nanorods were synthesized via solvothermal route with the addition of KI. The products were characterized with X-ray powder diffraction patterns and transmission electron microscope images. Their optical properties were studied by UV-vis transmittance and photoluminescence spectrum. The band gap of direct forbidden transitions was found larger than that of bulk materials, because of the blue shift caused by nanometer-scale crystalline particles due to quantum confinement effects. A possible growth mechanism is proposed.
- Ni, Youbao,Shao, Mingwang,Wu, Zhengcui,Gao, Feng,Wei, Xianwen
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p. 297 - 300
(2008/10/09)
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- Phase equilibria of the Tl2S-Tl2Se-TlI system
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Phase equilibria of the Tl2S-Tl2Se-TlI ternary system are investigated by DTA and X-ray powder diffraction techniques using mathematical modeling. Phase diagrams for the Tl2S-Tl2Se, Tl2S-Tl5Se2I, and Tl6SI4-Tl 6SeI4 quasi-binary joins as well as the Tl 3SI-Tl5Se2I polythermal section are constructed. The character of physicochemical processes at invariant points is described.
- Barchii,Peresh,Sabov,Gaborets,Kun
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p. 1568 - 1571
(2008/10/08)
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- Tl2Se-Sb2Se3 and TlSe-TlSbSe2 (Tl9SbSe6) Systems
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The phase equilibria in the Tl2Se-Sb2Se3 and TlSe-TlSbSe2 (Tl9SbSe6) systems are studied by DTA, X-ray powder diffraction, and microhardness and emf measurements. Phase diagrams are constructed for these systems. Both of them are quasibinary. In the Tl2Se-Sb2Se3 system, four ternary compounds - TlSb3Se5, TlSbSe2, Tl3SbSe3, and Tl9SbSe6 - are formed.
- Dzhafarov,Babanly,Kuliev
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p. 779 - 781
(2008/10/08)
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- The Tl-Sb-Se System
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The Tl-Sb-Se system is studied by differential thermal analysis, X-ray diffraction analysis, by microhardness measurements, and by measurements of the electromotive force of electrolyte-concentration cells. The TlSbSe2-Se(Tl) and TlSe(Tl3Sb)-Sb2S3 vertical sections, the projection of the liquidus surface on the composition triangle, and the 300 K level section of the phase diagram are constructed. Chemical compounds Tl9SbSe6, Tl3SbSe3, TlSbSe2, and TlSb3Se5 and an extended Tl2-xSe-Tl9SbSe6 solid solution are found to exist. The existence of the Tl4SbSe2, Tl3SbSe2, Tl2SbSe2, Tl6Sb8Se13 compounds reported in earlier publications is not confirmed. The standard thermodynamic functions of formation of Tl3 SbSe3 are determined.
- Dzhafarov,Babanly,Kuliev
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p. 1278 - 1284
(2008/10/08)
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- TI2Se-Sb, TI9SbSe6-Sb, TISe-Sb, and TISbSe2-Sb Systems
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The Tl2Se(Tl9SbSe6, TlSe, and TlSbSe2)-Sb sections through the Tl-Sb-Se systems were studied by DTA, X-ray diffraction, and microhardness measurements. These sections are stable in their subsolidus portions. The compounds Tl4SbSe2, Tl3SbSe2. and Tl2SbSe2 reported previously were not detected. The specified compositions are heterogeneous mixtures Tl2Se + Sb, Tl9SbSe6 + Sb, and Tl3SbSe3 + Sb, respectively.
- Dzhafarov,Babanly,Kuliev
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p. 619 - 621
(2008/10/08)
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- Neutron diffraction study of liquid Tl-Se alloys
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A neutron diffraction study on the liquid T1-Se system has been carried out over the whole concentration range. Profiles of the total structure factors or the pair distribution functions are essentially similar to those of pure liquid T1 up to 66.7 at.% T1 content, suggesting that there forms a certain short range order in the liquid state which is not far from the structure in the sense of short range scale of the pure liquid Tl. The existence of covalent-type Se polymeric structure is confirmed in Se-rich composition range. We have also derived the partial structure factors, using three different total structure factors in a small concentration range, where the partial structure factors were assumed to be constant.
- Usuki, Takeshi,Shirakawa, Yoshiyuki,Tamaki, Shigeru
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p. 2805 - 2813
(2008/10/08)
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- The System Thallous Iodide - Thallous Selenide and the Structure of the Tl6X4Y Compounds
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The system TlI - Tl2Se was investigated by DTA , X-ray and metallographic methods.At the Tl2Se corner of the system a solid solution up to 25 molpercent TlI is observed, which decomposes peritectically at 681 K.Two new compounds Tl5ISe2 and Tl6I4Se were found.The latter is isotypic to a class of compounds found in the TlX-Tl2S systems.The crystal structure of Tl6Cl4S was determined.It is based on the TlCl structure (CsCl-type) in which 1/5 of the Tl or Cl atoms, resp., are substituted by Tl2S in a regular manner.The coordination of the anions (Cl, S) is very similar to the coordination of Cl in TlCl or S in Tl2S resp.
- Blachnik, R.,Dreisbach, H. A.,Engelen, B.
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p. 139 - 142
(2007/10/02)
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