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1.
Magnetic susceptibilities were measured from 2.2 K to room temperature for solid solutions of UO2ThO2ZrO2 of which the lattice parameters are the same as that of UO2, i.e., Th0.7yZr0.3yU1−yO2 solid solutions. The Néel temperature decreases linearly with decreasing uranium concentration, the critical concentration being 69 mole% UO2. The Néel temperatures of the present solid solutions are nearly in the middle of UO2ThO2 solid solutions and UO2ZrO2 solid solutions, which indicates that the magnetic dilution effect of ZrO2 is larger than that of ThO2. The effective magnetic moment decreases with decreasing uranium concentration, which is due to a decrease in the magnetic interactions with adjacent uranium ions, not due to a change of the strength of crystalline field. The Weiss constant decreases almost linearly with decreasing uranium concentration.  相似文献   

2.
《Fluid Phase Equilibria》1988,39(1):101-110
Bubble-point pressures of the H2COCO2 system were measured at temperatures from 253.15 to 303.15 K and pressures up to 9 MPa. Multiple bubble-points were observed within certain limits of hydrogen compositions. The data have been compared with the calculated results by the Redlich-Kwong and the Peng-Robinson equations of state.  相似文献   

3.
The extent of the glass forming region is described as a function of the composition and of the cooling speed. The shape of this region is explained from the previously described La2S3La2O3Ga2O3Ga2S3 phase diagram. Glasses are obtained after relatively slow cooling (5°/min), in a definite region of compositions, which coincides with a relatively large concentration of ternary invariants. The thermal properties (transition temperatures and crystallization temperatures) were measured by DTA. For a relatively large region of compositions, glasses return to the equilibrium conditions with intermediate formation of the La3.33Ga6S12O2 metastable crystalline phase. An approach to the structure of the glasses is made by comparison with the crystal structures of the numerous ternary and quaternary crystalline compounds observed in the system, and by the comparison of the Raman spectra. It appears that these gallium oxysulfide glasses have many structural analogies with germanium sulfide glasses.  相似文献   

4.
5.
PtCl42− with the ligand HS(CH2)3Cl affords a linear polymer which is converted into the hexamer title compound by heating in xylene in the presence of a small amount of dimethylsulphoxide. The hexamer undergoes Cl substitution upon reaction with NaBr or NaI. From the reaction of PtCl2 with the Grignard reagent of o-allyl-p-methyl-chlorobenzene is obtained the monomer complex Pt[C6H3(CH2CH  CH2-o) (CH3p)]2. The biological properties of the complexes as inhibitors of DNA, RNA and protein synthesis has been evaluated.  相似文献   

6.
《Materials Chemistry》1981,6(4-5):287-297
The phase diagram Ag2OV2O5TeO3 is studied in the region rich in TeO2 with the aid of DTA and X-ray analysis. It is found that the sections TeO2Ag2O.V2O5.2TeO2 and Ag2O.TeO2Ag2O.V2O5.2TeO2 are simple ones. A new compound with a composition of Ag2O.3V2O5.6TeO2 has been found in the section 2TeO2.V2O5Ag2O.V2O5.2TeO2 which melts incongruently. A part of the liquidus diagram of the system in which the two ternary compounds participate is plotted.  相似文献   

7.
The systems CaCl2SrCl2 and CaCl2EuCl2 were studied over the entire composition range by X-ray powder diffraction. The CaCl2XCl2 (X = Sr, Eu) systems behave similarly and exhibit two single-phase regions with corresponding adjacent two-phase regions. The first single-phase region exhibits the SrI2-type and the second the SrBr2-type structure. The cation distribution is probably random throughout the systems.  相似文献   

8.
A systematic study of compound and solid-solution formation in the system Li2ONb2O5TiO2 has been made. Several solid-solution series, based on LiNbO3, LiNb3O8, Li2Nb28O71, Li2TiO3, phase M, Li2Ti3O7, and TiO2, have been characterized. In all cases, the principal solid-solution mechanism appears to involve stoichiometric formulae with constant overall cation content. One new phase, of approximate formula Li13TiNb5O21, has been prepared. A subsolidus phase diagram for the ternary system is presented.  相似文献   

9.
The ternary system YPO4Ca3(PO4)2Ca2P2O7 has been investigated by differential thermal analysis, powder X-ray diffraction, and microscopy in reflected light. Its phase diagram and isothermal section at room temperature have been determined. The system contains only one double phosphate which is formed at the 1:1 molar ratio YPO4:Ca3(PO4)2, i.e., Ca3Y(PO4)3.  相似文献   

10.
The liquid-liquid extraction model for a binary metal system successfully applied to the lanthanide nitrate system was found to be applicable to the binary metal-mixed ligand system only when equal mole fractions of each metal components are present in the feed solution. The agreement in this special case is explained satisfactorily in terms of the two-suffix Margules equations. The lack of agreement between the chemically based model and the experimental data was attributed to the effects of the stability constants and the degree of formation of the lanthanide mixed ligand complexes on the separation factors.  相似文献   

11.
Parameter values of the non-blonded atom⋯atom interaction Br⋯OC have been established from gas-phase data. Conformational energies, structures, torsional barrier heights and torsional force constants of the title compounds have been estimated. For BrOCCH2Br, (Cl3C)2CO and (ClH2C)2CO the calculated results are compared with gas-phase observations. It is suggested that hexachloroacetone ought to be reinvestigated by electron diffraction.  相似文献   

12.
《Solid State Sciences》2000,2(4):489-493
The partial system Mg3(PO4)2Mg4Na(PO4)3Na4P2O7Mg2P2O7 in the ternary system MgONa2OP2O5 was investigated using thermal and X-ray diffraction analyses and microscopy, and its phase diagram has been determined. In this range of composition, two binary phosphates occur: Mg4Na(PO4)3 and Mg6Na8(P2O7)5. The former melts incongruently (at 1155°C) and the latter does congruently (at 808°C). In the partial system of interest, the two sections Mg4Na(PO4)3Mg2P2O7 and Mg4Na(PO4)3Mg6Na8(P2O7)5 are studied, and their phase diagrams are established. The partial system is divided into three partial ternary systems in which two ternary eutectics and one ternary peritectic occur.  相似文献   

13.
It has been found experimentally that phase diagram for the system Bi2O3CaOSrOCuO in SrO-rich region at 850°C in the open air includes three elementary tetrahedra: CaOSrOSr6Bi2O11Sr2CuO3, CaOSr2CuO3Sr6Bi2O11Sr3,5Ca0,5Bi2O7 and Sr3Bi2O6Sr6Bi2O11Sr3,5Ca0,5Bi2O7 Sr2CuO3. In the considered interval of corresponding oxide concentrations quaternary oxides are not formed under the above conditions.  相似文献   

14.
Two new oxyborate compounds were synthesized during a study of the phase relationships between the pinakiolite-ludwigite series of compounds. The structural topologies of these previously unreported materials have been determined experimentally by comparing calculated with observed electron microscope images. Both of these structures are very similar to each other, and also closely related to pinakiolite which consists of flat walls of edge-sharing octahedra connected to zigzag chains of octahedra by triangular BO3 groups. The two new structures contain similar infinite walls which are separated by slabs of octahedra that are wider than the zigzag chains found in pinakiolite. A new series of structurally related oxyborate compounds can be envisaged and are described.  相似文献   

15.
16.
《Solid State Sciences》2000,2(4):495-500
The polythermal diagram of the ternary system H2ONa2HPO4Na2SO4 has been established, setting up nine isotherms obtained between 0 and 25°C by conductimetric analysis. The solubility domains of the various solid phases have been determined. One eutectic, three stable and one metastable transitional transformations have been observed. Temperature and composition of the eutectic point have been obtained by thermal analysis at constant flow.  相似文献   

17.
The excess enthalpies of the liquid alloys GaGeTe and GaSnTe were measured in a heat-flow calorimeter at 1203 K. The enthalpy surface in the ternary space in both systems is characterized by a valley stretching from the exothermic minimum in the GaTe system to the minima of the GeTe and SnTe systems. The minima in the ternary systems were found in this valley, i.e. on the sections Ga2Te3-GeTe and Ga2Te3-SnTe. A comparison of the experimental data with those calculated from the excess enthalpies of the constituent binaries with the aid of the Bonnier model, reveals only small deviations. A preliminary investigation was made into the ternary phase diagram of GaSnTe. This system contains the two quasibinary sections Ga2Te3-SnTe, GaTe-SnTe and the ternary compound Ga6SnTe10. The previously reported compounds Ga2SnTe3 and GaSnTe2 do not exist.  相似文献   

18.
NdFeB and corresponding MmFeB compounds were studied, the high field magnetization at 4.2 K, the a.c. susceptibility (4.2 < T < 300 K) and the anisotropy field were measured using the singular point detection technique (77 < T < 570 K). At room temperature the anisotropy field of the MmFeB is about 3T, whereas that of NdFeB compounds is about 7T. The MmFeB compounds showed effects due to the cerium (lowering the Curie temperature) as well as due to the neodymium (spin reorientation at low temperatures).  相似文献   

19.
Using different calorimeters, the following measurements have been carried out.
  • 1.(i) The integral enthalpies of mixing of CeCu binary and some CeMgCu ternary liquid alloys,
  • 2.(ii) The enthalpy of formation and the enthalpy of melting of the intermetallic compound CeCu2.
  • 3.(iii) The heat content of solid and liquid CeCu2.
The observed concentration and temperature dependence of the measured values of the enthalpies of mixing as well as the glass-forming abilities of these alloys are explained on the basis of an association model.  相似文献   

20.
The glass-forming region in the SiS2Li2SLiX (X = Br, I) system, as determined by X-ray diffraction, has been extended to higher lithium content by the use of a direct liquid nitrogen quench. The base glass, 0.4SiS20.6Li2S, was synthesized and doping up to 0.28SiS20.42Li2S0.30LiBr and 0.24SiS20.36Li2S0.40LiI was achieved. The properties of these glasses are compared to the glasses formed by previously reported quenching methods.Vibrational assignments have been made from infrared investigation of the glasses using FT-IR. The basic glass network consists of SiS4 tetrahedra while the addition of Li2S as a network modifier produced nonbridging sulfur. Doping with lithium halide did not significantly change the glass network, i.e., no changes in IR peak positions were observed. However, the higher lithium ion concentration resulted in higher mobility and ionic conduction.  相似文献   

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