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1.
The solubilities of Yb(ClO4)3·3H2O-18C6-C2H5OH ternary system at 25 were invstigated by a semimicro method for study of phase equilibrium.and the refractive indexes of saturated solutions were determined.The behavior of water in this system during the equilibrium was examined.The results indicate that there are two kinds of complexes formed in the system, their chemical compositions are: Yb(ClO4)3·18C6·3H2O·2C2H5OH (I) and Yb(ClO4)3 18C6·3H2O·C2H5OH.Both are incongruently soluble in EtOH.The influences of rare earth ions and salt anions on formation of complexes were discussed.The two solid complexes have been prepared, and their composihons and properties have been investigated by chemical analysis, IR, DTG and DSC.According to the DSC, the enthalpies of some steps during the decomposition have been obtained for complexes (Ⅲ)and (Ⅳ).  相似文献   

2.
The α-Fe2O3 hollow spheres have been synthesized through the random aggregation of β-FeOOH nanorods in the C2H5OH/H2O system. The phase transformation and the morphologies of the α-Fe2O3 hollow structure were investigated with XRD, SEM, TEM and selected area electron diffraction (SAED). These studies indicate that the second step is a dissolution-recrystallization process. Furthermore, the formation mechanism of the hollow spheres has been discussed. It is found that the presence of H2O in the reaction system is essential to the final formation of the hollow spheres.  相似文献   

3.
The isothermal solubility of the ternary system Cu(NO3)2-EBU-H2O at 30℃ has been studied for the first time and the solubility diagram and refractive indices diagram have been given. New phase Cu(NO3)2·2EBU has been found in this system, which dissolves incongruently in water .The phase has been characterized by element anal-ysis, IR spectra and X-ray diffraction powder analysis.  相似文献   

4.
The equilibrium solubilities of the quaternary system CsCl-TmCl3-HCl-H2O was determined at 25 ℃ and the corresponding equilibrium diagram was constructed. The diagram is a complicated system with limited solid solutions and formation of a new compound 3CsCl·2TmCl3·14H2O. The new compound has been characterized by XRD, TC-DTG and fluorescence spectrometry. Results show that upconversion spectrum exhibits at 335 nm when exciting at 860 nm, and fluorescence spectrum exhibits at 295 nm and 385 nm when exciting at 240 nm. The compound loses its crystal water by four steps at 50 to 250 ℃. Using a heat conduction calorimeter, the standard molar enthalpy of dissolution of 3CsCl·2TmCl3·14H2O was determined to be (-11.601 ± 0.050) kJ·mol-1 at 298.15 K.  相似文献   

5.
The equilibrium solubilities of the ternary system YCl3-CdCl2-H2O, the quaternary system YCl3-CdCl2-HCl(~8.8%)-H2O were determined at 25 ℃ and the phase diagrams were constructed. The results show that the ternary system was complicated with six equilibrim solid phases CdCl2·2.5H2O, CdCl2·H2O, 8CdCl2·YCl3·15H2O (8∶1 type), 4CdCl2·YCl3·13H2O(4∶1 type), 5CdCl2·2YCl3·26H2O (5∶2 type) and YCl3·6H2O. The quaternary system was also complicated with four equilibrim solid phase CdCl2·H2O, 4CdCl2·YCl3·13H2O (4∶1 type), 5CdCl2·2YCl3·26H2O(5∶2 type) and YCl3·6H2O. Among the three new compounds 8CdCl2·YCl3·15H2O, 4CdCl2·YCl3·13H2O and 5CdCl2·2YCl3·26H2O, 8CdCl2·YCl3·15H2O was a kind of metastable compound only in ternary system, and it was changed into 4CdCl2·YCl3·13H2O with time. Both 4∶1 type and 5∶2 type existed in ternary and quaternary system, but they were also congruently soluble compounds in quaternary system. They have been prepared from the system and have been characterized by XRD, TC-DTG and DSC.  相似文献   

6.
纳米固体超酸SO42-/TiO2的研究   总被引:37,自引:0,他引:37  
The new nanosolid superacid catalyst SO42-/TiO2 is compounded with nanometer chemical technology. This catalyst SO42-/TiO2 has good catalytic effects on esterificational reactions of ethylic acid and ethyl alcohol. It has many other advantages such as strong water-proof quality, being able to be used repeatedly, being easy to be re-claimed, non-corroding, non-polluting. So it is a green industrial catalyst which is helpful to the environment and possesses wide prospect of applications. The crystallo-process, specific surface area and sulphur content of the SO42-/TiO2 system have been studied with the method of XRD, XPS and the chemical analysis, the result of which indicates that catalytic activity and acid strength of SO42-/TiO2 is affected by the H2SO4 saturant concentration, baking temperature, precipitating condition, specific surface area and sulphur content. The best preparation conditions of SO42-/TiO2 are: ageing temperature at 0℃, 0.5mol·L-1 of H2SO4 concentration, baking temperature at 500℃and 3 hours of baking time.  相似文献   

7.
The equilibrium solubility of the LaCl3-CdCl2-(9.7%)HCl-H2O quaternary system at 298K was determined and the phase diagram was constructed. The results show that the system is complicated with four equilibrium solid- phases CdCl2·H2O, 8CdCl2·LaCl3·16H2O(8∶1 type), 4CdCl2·LaCl3·12H2O(4∶1 type) and LaCl3·7H2O, respectively. The two new compounds 8CdCl2·LaCl3·16H2O(8∶1 type) and 4CdCl2·LaCl3·12H2O(4∶1 type) are congruently soluble in ~9.7% HCl-H2O medium and have not yet been reported in literatures. Both com-pounds have been prepared from the system and have been characterized by XRD, TG-DTG and DSC.  相似文献   

8.
Both whisker and nanometer MgSO4·5Mg(OH)2·3H2O(MOS) were prepared by hydrothermal method at 140℃ for different times, using NaOH and MgSO4·7H2O as raw materials. The MgSO4·5Mg(OH)2·3H2O part- icles were characterized by powder X-ray diffraction(XRD),thermal analysis(TGA-DSC), infrared spectroscopy(FT-IR),transmission electron microscopy(SEM) and scanning electron microscopy(TEM). The size distribution in whisker-like and nanocrystalline materials are in the range of 10~50μm and 10~20nm respectively. The whisker MOS is metastable phase in MgSO4-NaOH-H2O system at 140℃,whereas nanometer MOS is stable phase.  相似文献   

9.
化合物Cs5EuCl8·14H2O和Cs2EuCl5·4H2O的制备和荧光性   总被引:4,自引:0,他引:4  
The two new compounds Cs5EuCl8·14H5O(5∶1 type) and Cs2EuCl5·4H2O(2∶1 type) were found and syn-thesized from CsCl-EuCl3-11%HCl-H2O quaternary systems by phase equilibrium method, and were characterized and measured by ultra-violet absorption spectrometry and fluorescence spectrum. The results show that upconversion spectrum exhibit at 590nm and 610nm exited at 790nm, and the upconversion intensity increases with the EuCl3 ratio increasing in CsCl.  相似文献   

10.
5Mg(OH)2·MgSO4·2H2O晶须生长过程中的形貌研究   总被引:7,自引:0,他引:7       下载免费PDF全文
Using MgSO4 and NaOH solutions as starting materials, the whisker of 5Mg(OH)2·MgSO4·2H2O has been prepared by hydrothermal method at 160℃ for different time. The whisker was separated, washed by water, ethanol and ether,and characterized by chemical analysis, XRD, IR and microphotography. The growth time of whisker would affect its morphology.  相似文献   

11.
In this paper,the forming and transforming process of the magnesium oxysulfates in a quaternary interaction system of MgSO4-NaOH-H2O under the hydrothermal conditions at 180℃ has been investigated by using MgSO4 and NaOH solutions as starting materials. This transforming process of product phase from unstable phase to stable phase with time has been proved by means of chemical analysis, microphotograph, XRD and IR.  相似文献   

12.
三元系RbCl-C2H5OH-H2O液固相平衡及其物化性质研究   总被引:2,自引:0,他引:2  
张军  高世扬  夏树屏 《无机化学学报》2002,18(12):1241-1244
The isothermal solubility and physico-chemical properties (density, refractive index) of ternary system RbCl-EtOH-H2O at 25℃ and 50℃ have been firstly investigated by means of self-made micro-equilibrium and sampling apparatus .The compositions of liquid and solid at equilibrium state were determined, and the problem of analysis of ethanol content in system was properly solved. The phase diagram was drawn by the TPD phase-diagram computer program developed by us. Three empirical formulae were proposed to correlate the solubility, density and refractive index respectively. No demixing phenomena was observed in the range of temperature related in this study.  相似文献   

13.
五元体系Li+/Cl-,CO32-,SO42-,B4O72--H2O 298 K相关系实验研究   总被引:2,自引:0,他引:2  
Zabuye saline lake, Tibet, China, is unrivalled in the world for its high concentration of chloride, sulfate, carbonate and borate of lithium, sodium and potassium. Always at the later stage of the evaporation of brines, most sodium and potassium salts are crystallized out, so the main components of brines can be described with the Li+, Mg2+/Cl-, SO42-, CO32-, B4O72--H2O system. As a part of study on the equilibrium of this complex system, the equilibrium solubilities and phase diagram of the quinary system Li+/Cl-,CO32-,SO42-,B4O72--H2O at 298 K were studied by isothermal dissolution equilibrium method. In the 3-dimentional solubility diagram or its projection diagram saturated with solid LiCl, there are four crystallization fields, four univariant curves and one invariant point. At the invariant point, the saturated solid salts are LiCl·H2O, Li2B4O7·3H2O, Li2CO3and Li2SO4·H2O. No double salt or solid solution is formed.  相似文献   

14.
The optimum volume ratio of Zn(AA) SO4 · H2O crystallizing from mixed solvent of water with acetone has been determined, which are 1∶3, 1∶9, 1∶10, and 1∶30 of water∶acetone, respectively. The crystal growth pro-cesses of the compounds at 298.15K are investigated by microcalorimetry. The experimental results show that the processes are in accord with the Burton-Cabrera-Frank dislocation theory.  相似文献   

15.
溶剂热还原合成Cr2O3纳米管(英)   总被引:2,自引:0,他引:2  
Cr2O3 nanotubes with diameters of 80 nm and lengths of 550 nm were synthesized in a solvothermal reduction system at 180 ℃. The acetyl acetone (AcAc) and ethylene glycol (EG) were used as the chelate agent and the reductant respectively in the system. An intermediate compound-Cr(Ⅲ)(C5H7O2)3 was formed to force Cr2O3to crystallize along one direction.  相似文献   

16.
Nafion? / TiO2复合膜的质子传导性能研究   总被引:1,自引:0,他引:1  
Nafion® / TiO2 composite membranes were prepared by in-situ chemical reaction method using Ti(OC4H9)4 and Nafion® 117 as raw materials. The membranes were characterized by UV, FTIR-ATR and XRD, respectively. Methanol permeability and water uptake were investigated as a function of TiO2 contents. The conductivity of the membranes was measured under water vapor pressure (2.644 7 kPa) or in dry atmospheres. The XRD results showed that the titanium dioxide in Nafion® membranes were crystallized in anatase phase with an average crystaline diameter of 3.0 nm. The water uptake of the composite membranes was larger than that of the pure Nafion® membrane when the TiO2 loading was within 14wt%. The methanol permeability of the membrane decreased as the TiO2 loading increased. The addition of 3wt% TiO2 to Nafion® membranes improved the conductivity in dry measurement conditions. The proton conductivity of the composite membrane increased greatly after the hydrothermal treatment at 160 ℃ for 2 hours.  相似文献   

17.
CuInS2 thin films have been prepared by ion layer gas reaction (ILGAR) using C2H5OH as solvent, CuCl and InCl3 as reagents and H2S gas as sulfuration source. The effects of cationic concentrations and numbers of cycle on the properties of CuInS2 film were investigated. The chemical composition, crystalline structure, surface topography, deposited rate, optical and electronic properties of the films were characterized by X-ray diffractrometry (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), ultraviolet-visible spectrometry (UV-Vis) and Hall System. The results show that the crystalline of CuInS2 thin films and the deposition rate have been improved with the increase of cationic concentration, while CuxS segregation phases appear with further increasing cationic concentration. The deposition rate is close to constant as cationic concentration is fixed. CuInS2 thin film derived form lower cationic concentration is uniform, compact and good in adhesion to the substrates. The absorption coefficient of CuInS2 thin films is larger than 104 cm-1, and the band gap Eg is in the range of 1.30~1.40 eV. The dark resisitivity of the thin film decreases from 50 to 10 Ω·cm and the carrier concentration ranges are over 1016 cm-3.  相似文献   

18.
钠硼解石——水体系溶解和相平衡的研究(英)   总被引:3,自引:0,他引:3  
Ulexite dissolution in water has been studied in the wide temperature range from 10℃ to 93℃ and two higher temperatures at 120 ℃ and 240 ℃. The analytical results showed that ulexite dissolved congruently from 10 ℃ to 35 ℃ and incongruently from 40 to 68 ℃. The solid component of ulexite, NaCaB5O6(OH)6·5H2O was dehydrated to form NaCaB5O6(OH)6·H2O from 50 to 68 ℃ and finally amorphous solid at 68 ℃. This amorphous solid converted into priceite at 71 ℃ and then converted completely to priceite at the boiling point(93℃) of the solution. At both 120 and 240 ℃, the dissolution of ulexite was an incongruent process. Above 120 ℃, ulexite became amorphous solid and then transformed into priceite. In addition to the solid to solid transformation, crystallization of priceite from the solution has also been observed. Based on our experimental results, mechanisms of dissolution, transformation, and crystallization of borate in ulexite-water system are discussed.  相似文献   

19.
Open-framework metal phosphates have been the subject of intense research owing to their interesting structural chemistry and potential applications in catalysis and ion exchange. The gallium phosphate family has exhibits rich structural chemistry. A novel gallium phosphate Ga3P2O8(OH)3(H2O)(GaPO-CJ36) has been prepared in a hydrothermal reaction system of GaO(OH)-H3PO4-Co(chxn)3Cl3-H2O at 180 ℃ for 7 days. Single-crystal X-ray analysis shows that GaPO-CJ36 crystallizes in the P21/c space group with a=1.833 35(12) nm, b=0.503 94(3) nm, c=1.062 90(9) nm, V=0.982 01(12) nm3, and Z=4. The connection of GaO2(OH)3(H2O) octahedra, PO4 and GaO4 tetrahedra through vertex oxygen atoms forms a three-dimensional open framework, which contains 8-ring channels along the [010] direction. Its structure is composed of interesting [344484] cages, which have not been found in known gallium phosphates. CSD: 416779.  相似文献   

20.
A new complex, {[Cu(phen)3](SO4)(H3PCA)2(8H2O)}, was synthesized and structurally characterized by single-crystal X-ray analysis. The complex is composed of copper cations, sulfate anions, 1,10-phenanthroline, protocatechuic acid and lattice water molecules. The structure of H3PCA, SO42- and waters comprises packing of anionic three-dimensional network by hydrogen bonds with cavities. The complex can be considered as a model of host/guest supramolecule. The three-dimensional hydrogen-bonding network is the host species. The Cu(phen)32+ cations, guest species, occupied the cavities of the host. And the results demonstrate that the form of protocatechuic acid at pH< 1 should be free ligand. CCDC: 191733.  相似文献   

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