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1.
T. I. Krasnenko M. V. Rotermel’ S. A. Petrova R. G. Zakharov O. V. Sivtsova A. N. Chvanova 《Russian Journal of Inorganic Chemistry》2008,53(10):1641-1647
Phase relations in the Zn2V2O7-Cu2V2O7 system were studied by high-temperature X-ray diffraction and differential thermal analysis. The major phase constituents
of the system are solid solutions based on Zn2V2O7 and Cu2V2O7 polymorphs and their coexistence regions. The generation of α-Zn2 − 2x
Cu2x
V2O7 solid solution, where 0 ≤ x ≤ 0.30, leaves almost unchanged the stabilization temperature of the high-temperature zinc pyrovanadate phase. The α-Cu2 − 2x
Zn2x
V2O7 homogeneity range is 5 mol % Zn2V2O7. In the range 0.050 ≤ x ≤ 0.09 from 20 to ∼ 620°C, there is the two-phase field of α-Cu2V2O7 and β-Cu2V2O7 base solid solutions. At still higher temperatures, β-Zn2 − 2x
Cu2x
V2O7 and α-Cu2 − 2x
Zn2x
V2O7 coexist in the mixed-phase region. β-Zn2 − 2x
Cu2x
V2O7 solid solution, where 0 ≤ x ≤ 0.30, exists above 610 ± 5°C. The extent of the β′-Cu2V2O7-base solid solution is 9 to 65 mol % Zn2V2O7 at 615 ± 5°C, expanding to 0 mol % Zn2V2O7 with rising temperature.
Original Russian Text ¢ T.I. Krasnenko, M.V. Rotermel’, S.A. Petrova, R.G. Zakharov, O.V. Sivtsova, A.N. Chvanova, 2008, published
in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 10, pp. 1755–1762. 相似文献
2.
L. F. Brum Malta Marta Eloisa Medeiros 《Journal of Thermal Analysis and Calorimetry》2007,87(3):883-886
This work reports the study of Bi4V2–xBaxO11–1.5x (0.02≤x≤0.50)
series, which is a potential source of solid electrolytes to apply in oxygen
sensors. X-ray powder diffraction was used to point out the formation of major
ionic conductive phases and minor ones. The modifications of vanadate substructure
were probed, at short range, by Fourier-transform infrared spectroscopy. Differential
scanning calorimetry evidenced the formation of tetragonal γ phase, which
can be ionic conductive, for x=0.14. 相似文献
3.
M. G. Zuev 《Russian Journal of Inorganic Chemistry》2010,55(1):93-95
Solid-phase interactions in the V2O5-Ta2O5-MoO3 system were studied. The formation of com- pounds TaVO5 and VTa9O25 in the V2O5-Ta2O5 binary system was verified. Tetragonal VTa9O25-base solid solutions of the general formula Ta5 + 4x
V5 − 4x
O25 (x = 0.25–1) and TaVO5-base solid solutions of the general formula Ta
x
Mo1 − x
V2 − x
O8 − 3x
(x = 0.625–1) were found to form. Subsolidus phase equilibria in the V2O5-Ta2O5-MoO3 were determined. 相似文献
4.
P. Tabero 《Journal of Thermal Analysis and Calorimetry》2007,88(1):37-41
Solid solution phases of a formula Fe8V10W16–xMoxO85 where 0≤x≤4, have been obtained, possessing a structure
of the compound Fe8V10W16O85.
It was found on the base of XRD and DTA investigations that these solution
phases melted incongruently, with increasing the value of x, in the temperature
range from 1108 (x=0) to 1083 K (x=4) depositing Fe2WO6
and WO3. The increase of the Mo6+
ions content in the crystal lattice of Fe8V10W16O85
causes the lattice parameters a=b contraction with cbeing
almost constant. IR spectra of the Fe8V10W16–xMoxO85 solid solution phases have been recorded. 相似文献
5.
Phase relations in
the solid state in the FeVO4–Co3V2O8
system, in the whole range of components concentration have been studied.
It was found that the composition of the phase of the howardevansite type
structure, formed in the investigated system, corresponds with the Co2.616Fe4.256V6O24 formula. The phase of the lyonsite type structure
has a homogeneity range with the Co3+1.5xFe4–xV6O24 formula (0.476 formula (0.476<x<1.667).
The melting temperature and the volume of the unit cell of the lyonsite type
structure phase increases together with the rise of cobalt quantity contained
in it. Basing on the results of the DTA and XRD measurements a phase diagram
of the FeVO4–Co3V2O8
system up to the solidus line was constructed. 相似文献
6.
Perovskite Bi1−x
Y
x
FeO3 (0.0 ≤ x ≤ 0.1) oxides were prepared by a citrate-gel method. The crystal structure examined by X-ray powder diffraction indicates
that the samples were single-phase and crystallize in a rhombohedral (space group, R-3c no. 161) structure. The structural phase transition from rhombohedral to orthorhombic phase was observed at x = 0.10. Increase in magnetization was observed as a result of Y doping. The optical band-gap of (Bi, Y)FeO3 materials were determined. The observed increase in magnetization and low band-gap of (Bi, Y)FeO3 ceramics position them for potential magenotoelectric and photocatalytic applications, respectively. 相似文献
7.
Zh. A. Kochkarov M. V. Khubaeva Z. L. Khakulov 《Russian Journal of Inorganic Chemistry》2011,56(5):783-786
This is the first study of the NaBO2-Na2CO3-Na2MoO4-Na2WO4 quaternary system by differential thermal analysis. Na2[MoO4(x)WO4(1 − x)] solid solutions in the quaternary system are found to not decompose. 相似文献
8.
S. A. Gromilov S. V. Korenev I. V. Korolkov K. V. Yusenko I. A. Baidina 《Journal of Structural Chemistry》2004,45(3):482-489
Synthesis of five binary complex salts with an [Ir(NH3)5Cl]2+ complex cation is described. The counterions are [ReCl6]2–, [IrCl6]2–, [ReBr6]2–, and Cl–. A polycrystal X-ray diffraction study has been performed for [Ir(NH3)5Cl]2[ReCl6]Cl2, and its crystal structure has been determined. A series of Ir
x
Re1–x
phases (0.5 x > 1) were obtained by reductive thermolysis. For the Ir-Re system, the history of the V/Z(x) dependence has been refined.Original Russian Text Copyright © 2004 by S. A. Gromilov, S. V. Korenev, I. V. Korolkov, K. V. Yusenko, and I. A. BaidinaTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 508–515, May–June 2004. 相似文献
9.
A. M. Potapova G. V. Zimina I. N. Smirnova F. M. Spiridonov P. P. Fedorov 《Russian Journal of Inorganic Chemistry》2011,56(9):1453-1457
The 950°C isothermal section of the InPO4-Na3PO4-Li3PO4 ternary system was studied and constructed; one-, two, and three-phase fields are outlined. Five solid-solution regions exist
in the system: solid solutions based on the complex phosphate LiNa5(PO4)2 (olympite structure), the indium ion stabilized high-temperature Na3PO4 phase (Na3(1 − x)In
x
(PO4); space group Fm
[`3]\bar 3
m), the complex phosphate Na3In2(PO4)3, and the α and β phases of the compound Li3In2(PO4)3. A narrow region of melt was found in the vicinity of eutectic equilibria. All the phases detected in the system are derivatives
of phases existing in the binary subsystems. Isovalent substitution of lithium for sodium in Na3In2(PO4)3 leads to a significant increase in the region of a NASICON-like solid solution. 相似文献
10.
V. A. Prituzhalov E. I. Ardashnikova V. A. Dolgikh A. M. Abakumov 《Russian Journal of Inorganic Chemistry》2011,56(3):313-324
Tysonite solid solutions Bi1−x
Ba
x
O
y
F3−x−2y
in the BiF3-BiOF-BaF2 system were obtained by solid-phase synthesis in sealed copper tubes in an argon atmosphere at 873 K with subsequent quenching.
The solid solutions were studied by X-ray diffraction, electron diffraction, and impedance spectroscopy. On the basis of X-ray
powder diffraction data, the homogeneity ranges of the tysonite solid solutions were determined and the scheme of their location
in the BiF3-BiOF-BaF2 system at 873 K was suggested. Aliovalent substitutions in both the cation and anion sublattices Ba2+ → Bi3+ and O2− → F− made it possible to vary the concentration of anion vacancies. It was found that, at a high concentration of anion defects
at 873 K, the hexagonal tysonite modification with space group P63/mmc is stable. With a decrease in the defect concentration, the trigonal tysonite modification with space group $
P\bar 3c1
$
P\bar 3c1
becomes stable. An ordered monoclinic tysonite-type modification BiO
y
F3 − 2y
(0.13 < y < 0.23) was revealed. For the homogeneity ranges of all tysonite phases, dependences of the unit cell parameters and conductivity
on the composition along the sections with a constant barium or oxygen content were reported. The most probable location of
oxygen anions and anion vacancies in the tysonite structure is discussed. 相似文献
11.
Anna Blonska-Tabero 《Journal of Thermal Analysis and Calorimetry》2008,93(3):707-710
A new phase Cd4Fe7+xV9+xO37+4x, where −0.5<x<1.5, has been obtained in the solid-state in the FeVO4−Cd4V2O9 system. The temperature of incongruent melting and the unit cell volume of this phase decrease with decreasing the content
of cadmium. The IR spectrum and SEM image of the new phase are presented. 相似文献
12.
Huaibing Sun Yungui Chen Chenghao Xu Ding Zhu Lihong Huang 《Journal of Solid State Electrochemistry》2012,16(3):1247-1254
Spinel powders of LiMn2−x
RE
x
O4 (RE = La, Ce, Nd, Sm; 0 ≤ x ≤ 0.1) have been synthesized by solid-phase reaction. The structure and electrochemical properties of these electrode materials
were characterized by X-ray diffraction (XRD), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and charge–discharge
experiment. The part substitution of rare-earth element RE for Mn in LiMn2O4 decreases the lattice parameter, resulting in the improvement of structural stability, and decreases the charge transfer
resistance during the electrochemical process of LiMn2O4. As a result, the cycle ability, 55 °C high-temperature and high-rate performances of LiMn2−x
RE
x
O4 electrode materials are significantly improved with increasing RE addition, compared to the pristine LiMn2O4. 相似文献
13.
V. Ya. Kavun L. A. Zemnukhova A. I. Ryabov A. B. Podgorbunskii S. V. Gnedenkov S. L. Sinebryukhov V. I. Sergienko 《Russian Journal of Electrochemistry》2012,48(1):104-110
The methods of NMR, thermogravimetric analysis, and impedance spectroscopy were used to study ion mobility, phase transitions,
and ion conductivity in crystal phases in the KF-CsF-SbF3-H2O system. Analysis of 19F NMR spectra allowed tracing the dynamics of ion movement in the fluoride sublattice under temperature variations, determining
their types and temperature ranges, in which they are implemented. The observed phase transitions in potassium-cesium fluoroantimonates(III)
are phase transitions to the superionic state. It is found that the predominant form of ion movement in the high-temperature
modifications formed as a result of phase transitions becomes diffusion of fluoride ions. According to the results of electrophysical
studies the K1 − x
Cs
x
SbF4 (x ≤ 0.2) high-temperature phases are superionic. Their conductivity reaches the values of ∼10−2 to 10−3 S/cm at 463–483 K. The high-temperature phases are stabilized under cooling, which results in a significant increase in conductivity
at the room temperature. 相似文献
14.
The interaction between two similar plane double-layers for K4Fe(CN)6 type asymmetric electrolytes was investigated with the aid of λ parameter method. The interaction energies for the system
at positive surface potential were expanded in a power series. This formula covers with the bounds of all potential (y
0 ≤ 20). The accurate numeral results and V′ − ζ
d
curves were given for y
0 ≤ 20. When y
0 ≥ 2, V′ hardly changes with y
0. The interaction energies between two similar plane parallel double layers for the different type electrolytes at y
0 = 1 were compared. The present results are also fit for Th(NO3)4 type electrolytes at negative surface potential. 相似文献
15.
M. Boča V. Danielik Z. Ivanová E. Mikšíková B. Kubíková 《Journal of Thermal Analysis and Calorimetry》2007,90(1):159-165
The phase diagrams of the systems KF-K2TaF7 and KF-Ta2O5 were determined using the thermal analysis method. The phase diagrams were described by suitable thermodynamic model. In
the system KF-K2TaF7 eutectic points at x
KF=0.716 and t=725.4°C and at x
KF=0.214 and t=712.2°C has been calculated. It was suggested that K2TaF7 melts incongruently at around 743°C forming two immiscible liquids. The system KF-Ta2O5 have been measured up to 8 mol% of Ta2O5. The eutectic point was estimated to be at x
KF∼0.9 and t∼816°C. The formation of KTaO3 and K3TaO2F4 compounds has been observed in the solidified samples. 相似文献
16.
Electrical conductivity in the monoclinic Li2TiO3, cubic Li1.33Ti1.67O4, and in their mixture has been studied by impedance spectroscopy in the temperature range 20–730 °C. Li2TiO3 shows low lithium ion conductivity, σ300≈10–6 S/cm at 300 °C, whereas Li1.33Ti1.67O4 has 3×10–8 at 20 °C and 3×10–4 S/cm at 300 °C. Structural properties are used to discuss the observed conductivity features. The conductivity dependences
on temperature in the coordinates of 1000/T versus loge(σT) are not linear, as the conductivity mechanism changes. Extrinsic and intrinsic conductivity regions are observed. The change
in the conductivity mechanism in Li2TiO3 at around 500–600 °C is observed and considered as an effect of the first-order phase transition, not reported before. Formation
of solid solutions of Li2–
x
Ti1+
x
O3 above 900 °C significantly increases the conductivity. Irradiation by high-energy (5 MeV) electrons causes defects and the
conductivity in Li2TiO3 increases exponentially. A dose of 144 MGy yields an increase in conductivity of about 100 times at room temperature.
Electronic Publication 相似文献
17.
N. B. Babanly Z. E. Salimov M. M. Akhmedov M. B. Babanly 《Russian Journal of Electrochemistry》2012,48(1):68-73
The EMF method with a solid Cu+-conducting electrolyte of Cu4RbCl3I2 was sued to study the Cu-Tl-Te system in the temperature range of 300–420 K. A diagram of solid-phase equilibriums of this
system is constructed, partial molar functions of copper in alloys, standard thermodynamic functions of formation and standard
entropies of CuTlTe2, CuTl4Te3, Cu2TlTe2, Cu3TlTe2, Cu9TlTe5 triple compounds and Cu
x
Tl5 − x
Te3 solid solutions (0 < x < 1) are calculated. The obtained results confirmed the assumption as to the possibility of using this modification for the
EMF technique for thermodynamic studies of copper-containing triple systems, even if they contain a less noble component than
copper. 相似文献
18.
Rozalija Ninković Jelena Miladinović Milica Todorović Snežana Grujić Joseph A. Rard 《Journal of solution chemistry》2007,36(4):405-435
Isopiestic vapor pressure measurements were made for {xZnCl2+(1−x)ZnSO4}(aq) solutions with ZnCl2 molality fractions of x=(0,0.3062,0.5730,0.7969, and 1) at the temperature 298.15 K, using KCl(aq) as the reference standard. These measurements
cover the water activity range 0.901–0.919≤a
w≤0.978. The experimental osmotic coefficients were used to evaluate the parameters of an extended ion-interaction (Pitzer)
model for these mixed electrolyte solutions. A similar analysis was made of the available activity data for ZnCl2(aq) at 298.15 K, while assuming the presence of equilibrium amounts of ZnCl+(aq) ion-pairs, to derive the ion-interaction parameters for the hypothetical pure binary electrolytes (Zn2+,2Cl−) and (ZnCl+,Cl−). These parameters are required for the analysis of the mixture results. Although significant concentrations of higher-order
zinc chloride complexes may also be present in these solutions, it was possible to represent the osmotic coefficients accurately
by explicitly including only the predominant complex ZnCl+(aq) and the completely dissociated ions. The ionic activity coefficients and osmotic coefficients were calculated over the
investigated molality range using the evaluated extended Pitzer model parameters. 相似文献
19.
E. Yu. Pikalova V. G. Bamburov A. A. Murashkina A. D. Neuimin A. K. Demin S. V. Plaksin 《Russian Journal of Electrochemistry》2011,47(6):690-696
CeO2-based solid solutions with a fluorite structure are promising materials as electrolytes of medium-temperature electrochemical
devices: electrolytic cells, oxygen sensors, and solid oxide fuel cells. In this work, studies are presented of the effect
of the dopant cation radius and its concentration on the physico-chemical properties of the Ce1 − x
Ln
x
O2 − δ solid solutions (x = 0–0.20; Ln = La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Yb) and also of multicomponent solid solutions of Ce1 − x
Ln
x/2Ln′
x/2O2 − δ (x = 0–0.20; Ln = Sm, La, Gd and Ln′ = Dy, Nd, Y) and Ce1 − x − y
Sm
x
M
y
O2 − δ (M = Ca, Sr, Ba) obtained using the solid-phase synthesis technique. Electric properties of the samples were studied in the
temperature range of 623–1173 K and in the oxygen partial pressure range of 0.01–10−22 MPa. The values of oxygen critical pressure ( pO2 * )\left( {p_{O_2 }^* } \right) are presented, at which the ionic and electron conductivity values are equal. The values were calculated on the basis of
experimental dependences at 1023 K at the assumption that the ionic conductivity value is determined only by the dopant concentration
and its effective ionic radius and is independent of the oxygen partial pressure. 相似文献
20.
Heat capacity of unstable quenched solid solutions (Fe1−xNix)0.96S was measured by DSC (enthalpy method and scanning heating). According to optic microscopy and X-ray powder diffraction,
the samples are homogeneous phase of NiAs type with unit cell parameters changing regularly with composition.
Heat capacity changes with composition irregularly due to the difference in magnetic properties of the end members: C
p/1.96R=4.1 for Fe-rich samples and 3.3 for Ni-rich ones. There is no exact limit between two types of magnetic ordering. Instead,
samples with intermediate composition (0.7<x<0.8) show large fluctuations in C
p due to the inconsistency of alternative (FeS and NiS) types of magnetic ordering. 相似文献