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1.
Zh. A. Kochkarov 《Russian Journal of Inorganic Chemistry》2007,52(3):448-454
The four-component reciprocal system Na,K∥F, CO3, WO4 has been studied using differential thermal analysis in combination with projective and differential geometry. The a priori prediction of the crystallization path (CP) shows six quaternary invariant points; of them, three are eutectics and the others are peritectics. The dominant exchange and complexing reactions have been recognized. The following four-component systems have been studied: (NaF)2-(KF)2-K2CO3-K3FWO4 (1), (NaF)2-K2CO3-K2WO4-K3FWO4 (2), (NaF)2-Na2CO3-Na2WO4-K2WO4 (3),, and (NaF)2-Na2CO3-K2CO3-K2WO4 (4); the coordinates of all quaternary invariant points have been determined. 相似文献
2.
The quinary reciprocal system Li, K || F, Br, MoO4, WO4 was partitioned into simplexes using graph theory by writing an adjacency matrix and solving a logical expression. A tree of phases of the system was constructed. The tree of phases has a linear structure and consists of four stable partitioning tetrahedra, two stable pentatopes, and three stable hexatopes. In the quinary reciprocal system Li, K || F, Br, MoO4, WO4, crystallizing phases were predicted. The stable tetrahedron LiF–KBr–Li2MoO4–Li2WO4 of the quinary reciprocal system Li, K || F, Br, MoO4, WO4 was studied by differential thermal analysis and X-ray powder diffraction. There are no invariant equilibrium points in the tetrahedron. Continuous series of solid solutions Li2MoxW1–xO4 do not decompose. 相似文献
3.
P.A. Akhmedova A.M. Gasanaliev B.Yu. Gamataeva P.A. Khizrieva 《Russian Journal of Inorganic Chemistry》2017,62(10):1390-1399
The differentiation of the quaternary reciprocal system Li, K, Ca, Ba||F, WO4 was performed based on the graph theory using special software. Stable and metastable complexes of the system were found using a matrix of reciprocal pairs of salts. For the first time, by a set of physicochemical analysis methods (differential thermal, visual polythermal, and X-ray powder diffraction analyses), based on the method of thermal analysis of successive projections of the composition polytope, the quaternary system LiF–K2WO4–CaF2–BaF2–BaWO4, which is a stable complex of the quaternary reciprocal system Li, K, Ca, Ba||F, WO4, was studied and the coordinates of invariant points were determined. 相似文献
4.
A. A. Nepomnyashchiy E. A. Buluchevskiy A. V. Lavrenov V. L. Yurpalov T. I. Gulyaeva N. N. Leont’eva V. P. Talzi 《Russian Journal of Applied Chemistry》2017,90(12):1944-1952
Tungstate-containing aluminum oxide is suitable as a catalyst support for hydrodeoxygenation of sunflower oil, ensuring 81–83 wt % yield of liquid products at 380°С, 4.0 MPa, and feed space velocity of 1 h–1. The catalyst acidity increases with increasing tungsten oxide content, leading to an increase in the content of decarboxylation/decarbonylation products and isoparaffins in the product mixture. 相似文献
5.
I. A. Baidina V. D. Il’yashevich V. F. Malakhov A. V. Belyaev 《Journal of Structural Chemistry》2007,48(5):973-976
The complex Na3(NH4)2[Ir(SO3)2Cl4]·4H2O was examined with single crystal X-ray diffraction and IR spectroscopy. Crystal data: a = 7.3144(4) Å, b = 10.0698(5) Å, c = 12.3748(6) Å, β = 106.203(1)°, V = 875.26(8) Å3, space group P21/c, Z = 2, d calc = 2.547 g/cm3. In the complex anion two trans SO 3 2? groups are coordinated to iridium through the S atom. The splitting of O-H bending vibrations of crystallization water molecules and N-H ones of the ammonium cation is considered in the context of different types of interactions with the closest neighbors in the structure. 相似文献
6.
An approach for significantly suppressing N2O formation in reduction of NO by NH3 over V2O5–WO3/TiO2 (VWT) catalyst has been studied by coating different amounts of a Fe-exchanged zeolite (FeZ) onto the catalyst. FeZ-promoted VWT samples were characterized using N2 sorption, X-ray diffraction (XRD) analysis, and NH3 adsorption/desorption techniques to understand the primary role of FeZ in lowering N2O production levels. At high temperatures (≥450 °C), VWT gave N2O production with high concentrations, while N2O formation was noticeably reduced when using FeZ-promoted catalysts, which also showed somewhat lower NO removal activities (<5 %) at all temperatures. N2 sorption and XRD measurements revealed no perceptible physical or chemical alterations of each constituent, even in VWT catalysts after FeZ coating following high-temperature calcination. Adsorption of NH3 on unpromoted and FeZ-promoted catalysts and subsequent desorption yielded very complicated spectra for N2O that might primarily come from NH3 oxidation, and the interaction between V–NO species at temperatures >580 °C. NO on neighboring sites seems to be produced via decomposition of N2O generated at lower temperatures. The FeZ in the promoted VWT catalysts could be responsible for N2O decomposition and N2O reduction with unreacted NH3 at temperatures >400 °C, thereby significantly lowering N2O emission levels. This promotional effect bodes well for use in many industrial deNO x applications. 相似文献
7.
I. K. Garkushin V. A. Alekseev M. A. Demina 《Russian Journal of Inorganic Chemistry》2017,62(1):114-122
The quaternary reciprocal system comprising fluorides, chlorides, and tungstates of lithium and potassium was partitioned into simplexes using graph theory, and a phase tree of the system was constructed. In the cutting triangles LiF–KCl–Li2WO4 and LiF–KCl–LiKWO4 by differential thermal analysis, the melting points and compositions of ternary eutectics were determined, and the crystallization fields of phases are delineated. For each element of the state diagram, phase reactions were described. The compositions of crystallizing phases in the cutting triangles LiF–KCl–Li2WO4 and LiF–KCl–LiKWO4 were confirmed by X-ray powder diffraction analysis. 相似文献
8.
Monika Bosacka Anna Błońska-Tabero Elżbieta Filipek Jana Luxova Petra Šulcová 《Journal of Thermal Analysis and Calorimetry》2017,130(1):95-101
A new dichromium(III) cobalt(II) diphosphate(V) of the formula CoCr2(P2O7)2 was detected in the Co3Cr4(PO4)6–Cr(PO3)3 system. The new compound was obtained as a result of high-temperature solid-state reactions between CoCO3, Cr2O3 and (NH4)2HPO4 as well as between Cr(PO3)3 and Co3Cr4(PO4)6. CoCr2(P2O7)2 was characterized using XRD, DTA and IR methods. Results demonstrated that CoCr2(P2O7)2 crystallizes in the triclinic system and its unit cell parameters were calculated. Its infrared spectrum was presented. CoCr2(P2O7)2 melts incongruently at 1270±10 °C with a formation of solid α-CrPO4. The compound Co3Cr4(PO4)6, component of the system under study, was obtained for the first time as a pure phase. Its thermal stability was also investigated. Co3Cr4(PO4)6 is stable in air up to 1410 ± 20 °C. 相似文献
9.
Zh. A. Kochkarov Z. A. Sokurova Z. Zh. Kochkarov 《Russian Journal of Inorganic Chemistry》2018,63(7):944-949
The phase diagram of the ternary reciprocal system K, Pb∥Cl, WO4 was studied for the first time by the calculation–experimental method and differential thermal and X-ray powder diffraction analyses. Chemical interactions between components were described, metathesis and complexation reactions were revealed, and the coordinates of binary and ternary eutectics were found (mol %): e4(410°C, 48% KCl, 52% PbCl2), e5(424°C, 23% KCl, 77% PbCl2), P(490°C, 63.5% KCl, 36.5% PbCl2), e6(487°C, 91% PbCl2, 9% PbWO4), e7(428°C, 30.5% KCl, 60.5% PbCl2, 9% PbWO4) (eutectic in the stable section D2–PbWO4), e8(650°C, 80% KCl, 20% PbWO4), e9(650°C, 70% KCl, 15% K2WO4, 15% PbWO4) (binary eutectic in the stable section D1–KCl), E1(620°C, 59% KCl, 34% K2WO4, 7% PbWO4), E2(640°C, 75% KCl, 5% K2WO4, 20% PbWO4), E3(400°C, 46% KCl, 6% PbWO4, 48% PbCl2), E4(410°C, 21% KCl, 9% PbWO4, 70% PbCl2), and Pо(468°C, 56% KCl, 10% PbWO4, 34% PbCl2). 相似文献
10.
E. I. Frolov M. O. Shashkov I. K. Garkushin 《Russian Journal of Inorganic Chemistry》2016,61(5):645-650
Phase equilibria in the stable tetrahedron LiVO3–Li2MoO4–KBr–LiKMoO4 of the quaternary reciprocal system Li,K∥Br,VO3,MoO4 were studied by differential thermal analysis. The composition (mol %) and melting point of the alloy corresponding to a quaternary eutectic were determined: (24.2% LiVO3, 10.4% Li2MoO4, 13.5% KBr, 51.9% LiKMoO4, 407°С). 相似文献
11.
Gligor Jovanovski Branko Kaitner Orhideja Grupce Pance Naumov 《Central European Journal of Chemistry》2004,2(1):254-275
The crystal structure of tripotassium trisaccharinate dihydrate, K3(C7H4NO3S)3·2H2O, is triclic, space group\(P \bar 1, Z = 2\). It consists of three crystallographically independent potassium and saccharinato ions as well as two structurally different water molecules. Potassium coordination polyhedra are irregular, with K1 and K3 six-coordinated and the third one K2 seven-coordinated. The K?O distances range from 2.652(9) to 3.100(2) Å(mean: 2.790 Å) whereas the K?N distance is 3.025(3) Å. The water molecules W2 is disordered over three positions with occupancies of approximately 0.6, 0.2 and 0.2. The hydrogen atom (H1W1) of the ordered water molecule (O1W) is hydrogen bonded to the sulfonyl oxygen atom (O11) (R(O...O)=2.976(3) Å), whereas the other hydrogen atom (H2W1) is bifurcated to the carbonyl oxygen atom (O13) (R(O...O)=2.851(3) Å) and the disordered water molecules (O23W) (R(O...O)=3.067(12) Å). The carbonyl oxygens (O13, O23 and O33) and one of the disordered water molecules (O22W) are involved in C?H...O hydrogen bonds (R(C?H...O)=3.027(4)–3.304(9) Å). Structural characteristics of the studied compound are compared with the analogous trisodium trisaccharinate dihydrate and dipotassium sodium trisaccharinate monohydrate. Infrared and Raman spectra of the title compound have been analyzed in relation to the structure, and compared with the spectra of trisodium trisaccharinate dihydrate. 相似文献
12.
Crystal structure of α-Ag<Subscript>8</Subscript>S<Subscript>3</Subscript>SO<Subscript>4</Subscript>
T. A. Shestimerova A. S. Mityaev D. I. Davlyatshin A. V. Shevel’kov 《Moscow University Chemistry Bulletin》2012,67(1):13-18
The crystal structure of silver sulfide-sulfate α-Ag8S3SO4 was determined by X-ray powder diffraction data. The substance crystallizes in the tetragonal system and the space group P-4 with the unit cell parameters of α = 7.2032(4) Å, c = 5.1043(5) Å, Z = 1, R f = 5.55%, χ2 = 3.45. The layers in the structure of the compound formed by trigonal prisms of Ag6S connected to each other through the vertices are connected by the additional atoms of sulfur into a three-dimensional framework. Distorted tetrahedral anions of SO 4 2? are located in the cavities of the framework, the symmetry (D 2d ) of which was confirmed by the data of IR spectroscopy. 相似文献
13.
M. O. Shashkov E. I. Frolov I. K. Garkushin 《Russian Journal of Inorganic Chemistry》2018,63(3):378-382
The cutting tetrahedron LiVO3–KBr–KVO3–LiKMoO4 of the quinary reciprocal system Li, K||F, Br, VO3, MoO4 was studied by differential thermal analysis. The composition and melting point of the alloy corresponding to a quaternary eutectic were determined (11.3 mol % LiVO3, 18.0 mol % KBr, 57.0 mol % KVO3, 13.7 mol % Li2MoO4 + K2MoO4, 318°С). 相似文献
14.
I. V. Fedorova M. G. Kiselev L. P. Safonova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(12):2103-2109
The molecular dynamics simulation method was for the first time used to study the structural and energy parameters of H3PO4, H2PO4−, and (DMFA)H+ (protonated dimethylformamide) in liquid N,N-dimethylformamide. The predominant orientation of the nearest neighbors of H3PO4, H2PO4−, DMFA, and (DMFA)H+ was determined from ranked distribution functions. The most probable structure of H-bonded complexes was obtained. It was
shown that H3PO4 formed H-bonds with two DMFA molecules, and and (DMFA)H+ formed H-bonds with one molecule. The dependence of Coulomb interaction energies on the distance between H3PO4, H2PO4−, (DMFA)H+, and DMFA had the form of damped oscillations, as is characteristic of intermolecular interactions in pure DMFA. The molecular
dynamics simulation of the H2PO4−-(DMFA)H+-DMFA ternary system showed a high probability of the formation of contact ion pairs. 相似文献
15.
The densities of aqueous solutions of Me4NBr, Et4NBr, Bu4NBr, and Et(OH)3EtNBr were measured in the concentration range 0.002 to 0.05 mol⋅kg−1. The temperature of the determinations ranged from 275.15 to 279.15 K in 0.5 K steps, and the uncertainty of the densities
was around ±1×10−6 g⋅cm−3. Eleven concentrations were used for each of the salts.
It was found that all the solutes follow Despretz’ law. The absolute value of the Despretz’s constants increases with increasing
number of carbon atoms in the cation, except for Et(OH)3EtNBr which has the highest value. The ionic contributions to the Despretz’s constants were calculated.
The volumetric data obtained allows the calculation proposed by Kalgud and Pokale. The effective ionic radii were calculated
using a semi-empirical equation, as proposed previously by several workers. The nonlinearity of the plot of the ionic Despretz
constants versus effective ionic radius is confirmed. 相似文献
16.
S. P. Khranenko N. V. Kuratieva I. V. Korolkov S. A. Gromilov 《Journal of Structural Chemistry》2016,57(3):625-627
The structure of [Pb3(OH)4Co(NO2)3](NO3)(NO2)·2H2O is determined by single crystal X-ray diffraction. The crystallographic characteristics are as follows: a = 8.9414(4) Å, b = 14.5330(5) Å, c = 24.9383(9) Å, V = 3240.6(2) Å3, space group Pbca, Z = 8. The Co(III) atoms have a slightly distorted octahedral coordination formed by three nitrogen atoms belonging to nitro groups (Co–Nav is 1.91 Å) and three oxygen atoms belonging to hydroxyl groups (Co–Oav is 1.93 Å). The hydroxyl groups act as μ3-bridges between the metal atoms. The geometric characteristics are analyzed and the packing motif is determined. 相似文献
17.
Phase formation in the system Li2MoO4–MgMoO4–Sc2(MoO4)3 was studied by X-ray powder diffraction analysis and differential thermal analysis. Ternary molybdate LiMgSc(MoO4)3 was synthesized, which crystallizes in the triclinic system (space group P\(\bar 1\)). In the Li2Mg2(MoO4)3–Li3Sc(MoO4)3 section, a continuous solid solution in the rhombic system was found to form (space group Pnma). 相似文献
18.
I. V. Kalinina Z. A. Starikova F. M. Dolgushin D. G. Samsonenko V. P. Fedin 《Journal of Structural Chemistry》2004,45(5):861-864
The compound [Co(NH3)6]2[W4Se4(CN)12]·8.5H2O was obtained by evaporating an aqueous ammonia solution of K6[W4Se4(CN)12]·6H2O and CoCl2·6H2O complexes. The starting Co(II) of CoCl2·6H2O transforms into [Co(NH3)6]3+ when exposed to air in a water-ammonia medium. Crystal data: triclinic crystal system, a = 10.7750(8) Å, b = 12.2843(9) Å, c = 19.6539(14) Å; α = 90.213(2)°, β = 99.910(2)°, γ = 114.737(1)°, V = 2319.1(3) Å3, space group
, Z = 2, D
x
= 2.633 g/cm3.Original Russian Text Copyright © 2004 by I. V. Kalinina, Z. A. Starikova, F. M. Dolgushin, D. G. Samsonenko, and V. P. Fedin__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 5, pp. 905–908, September–October, 2004. 相似文献
19.
The conduction and transport numbers of charge carriers for composites in the systems MeWO4-WO3 (Me = Ca, Sr, Ba) are studied as a function of the temperature and the activity of oxygen in a gas phase. The transport numbers are determined by an emf method and are estimated from dependences of conductance on the activity of oxygen in a gas phase. The deficiencies of the given procedure as applied to investigation of properties of composite phases are analyzed. The materials under study are classified with a class of metacomposites. The concentration intervals of the ionic, mixed, and electronic conductions are determined. The conduction of composites of compositions (100 − x)MeWO4 ⋅ xWO3 is predominantly ionic at x ≤ 10 (Me = Ca), x ≤ 60 (Me = Sr), and x ≤ 45 (Me = Ba). The obtained data are explained in the framework of a model that represents a composite as a distributed matrix system where a film of surface phase MeW-s with a high mobility of oxygen ions plays the role of a connected matrix. It is presumed that the surface phase MeW-s possesses double-sided surface activity (α MeW-s ≤
) and a higher mobility with respect to MeWO4 and WO3. The discovered anomalies of dependences
(T) and partial dependences
, σel(T) are explained by a change in the stoichiometry, morphology, and the degree of connectedness of surface phase MeW-s caused by with a change in the temperature and composition of composites.__________Translated from Elektrokhimiya, Vol. 41, No. 6, 2005, pp. 680–693.Original Russian Text Copyright © 2005 by Neiman, Pestereva, Sharafutdinov, Kostikov.Published on the basis of a report delivered at the VII Meeting on Fundamental Problems in Solid-State Ionics (Chernogolovka-2004). 相似文献
20.
T. V. Gubanova I. K. Garkushin G. D. Sinitsin 《Russian Journal of Inorganic Chemistry》2018,63(4):543-548
The binary system KVO3–K2CrO4 and two ternary systems, LiBr–LiVO3–Li2CrO4 and KBr–KVO3–K2CrO4, were studied. In the ternary systems, the compositions and melting points of eutectic alloys were determined by differential thermal analysis: (49.0 mol % LiBr, 5.0 mol % LiVO3, 46.0 mol % Li2CrO4, 400°C) and (17.0 mol % KBr, 78.0 mol % KVO3, 5.0 mol % K2CrO4, 458°C), respectively. 相似文献