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1.
Zabuye Saline Lake, Tibet, China, is unrivalled in the world for its very high salinity, in particular, for the very high concentration of ions of lithium, potassium, and boron in the brine. It belongs to alkaline and carbonate-borate-type salt lake. As a part of the study on phase equilibrium of the 6component subsystem Li+, Na+, K+/C1-, CO2-3, B4O2-7-H2O of the brine system, a study on the reciprocal quaternary system Li+, K+/C1-, CO32-H2O at 298 K was done with isothermal dissolution equilibrium method in the present work. The phase equilibrium of the reciprocal quaternary system Li+,K+/C1, CO2-3-H2O at 298 K was studied with isothermal dissolution method in this work. The physicochemistry properties of the corresponding equilibrium solutions such as densities, viscosities, refractive index, conductivities and pH value were determined. The dried salt diagram of the system consists of four crystallization fields (KC1, Li2CO3, LiCI·H2O, K2CO3·3/2H2O) and five isothermal solubility curves.There are no double slat or solid solution found. Pitzer′s model of the electrolyte solution theory was used for parameterization from the results of solubility determination for subsystems and the prediction of solubilities for the reciprocal quaternary system was made. The solubility data of the experiment are in agreement with those calculated.  相似文献   

2.
三元体系KCl-SrCl_2-H_2O 25℃相平衡研究   总被引:1,自引:0,他引:1  
Phase equilibria in the ternary system KCl-SrCl2-H2O at 25 ℃ was studied by using the isothermal method. Density and refractive index of the solution were also determined. The phase diagram was plotted according to the experimental data. In the equilibrium phase diagram of KCl-SrCl2-H2O, there is one invariant point, two univariant curves and two regions of crystallization: KCl and SrCl2·6H2O. In the invariant point, the composition of the liquid phase (mass fraction, wB) was wKCl 7.22%, wSrCl232.31%, the solid phase was KCl and SrCl2·6H2O. Neither double salts nor solid solutions between KCl and SrCl2·6H2O were found, and dehydration of SrCl2·6H2O didn′t occur in the system. The system is a simple eutectic type.  相似文献   

3.
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   

4.
Metastable equilibrium solubilities and densities of quaternary system Li2SO4+Li2CO3+ Li2B4O7+H2O at 288 K were determined by isothermal evaporation method. According to the experimental data, the metastable equilibrium phase diagram was plotted. The metastable phase diagram had one invariant point F, three double saturated liquid curves E1F, E2F and E3F, and three crystallization fields corresponding to Li2SO4·H2O, Li2CO3 and LiBO2·8H2O. It was found that lithium sulphate(Li2SO4) had the highest concentrat...  相似文献   

5.
The metastable phase equilibria of the quaternary system NaCl+Na2CO3+Na2SO4+H2O were studied at 273.15 K. The salts' solubilities, densities and pH values of the equilibrated solution in this system were determined. According to the experimental data, the metastable equilibrium phase diagram, the diagram of density vs. composition and pH vs. composition diagram were plotted. The phase diagram consists of five univariant curves, four crystallization fields and two invariant points. The four crystallization fields correspond to sodium carbonate decahydrate (Na2CO3·10H2O), sodium sulfate decahydrate(Na2SO4·10H2O), sodium chloride(NaCl) and burkeite(2Na2SO4· Na2CO3), respectively. The crystallization field of sodium sulfate decahydrate(Na2SO4·10H2O) is the largest, which indicates that sodium sulfate is easy to saturate and crystallize from solution at 273.15 K.  相似文献   

6.
A novel polymer electrolyte with the formula of Li2B4O7-PVA for lithium-ion battery was synthesized and its ion conductivity and mechanical properties were also tested. It is found that the conductivity of the prepared polymer electrolytes is higher than that of LiClO4/PEO or LiClO4/EC-DMC by two or three orders in magnitude and a large delocalized bond formed in Li2B4O7-PVA lead to transportation of Li ion easier, this electrolyte possesses high thermo-stability and can be used under 200℃.  相似文献   

7.
A homogeneous longtime stabilized transparent nanometer TiO2 organic solution was obtained by means of the simultaneous hydrolysis and co-polycodensation of tetrabutyltitanate (TBT) and methacryloxypropyltrimethoxysilane (MAPTMS) by the sol-gel process. The particle size of nanometer titanium dioxide was controlled by use of bifunctional silanes, such as diphenyldimethoxysilane (DPDMS), diphenyldiethoxysilane (DPDES) and dimethyldiethoxysilane (DMDES). The effect of TiO2 content in the solution on the refractive index of system was discussed in detail. The result shows that the refractive index of solution increases linearly with TiO2 content. The refractive index of the three hybrid nanometer materials attained 1.6053, 1.5846 and 1.5346, respectively. The size of nanometer particles was characterized by TEM and the particle diameter thus obtained is in the range of 20-90 nm. FT-IR spectra of the materials show that the TiO-Si bond is formed.  相似文献   

8.
The solubilities, refraction indices and densities of saturated solution of Li+ , Na+ Cl- ,B4O72- -H2O reciprocal quaternary system at 0℃, 25℃ and 50℃ were determined by using isotherm method. Using total concentration of all the salts in solution as concentration coordinate(ordinate) the isothermal stereogram of solubility of the system was drawn. The results showed that the stable salt-pair of the system is Na2Cl2-Li2B4O7 and that there are two isothermal invariant points, eutonic ponit E and inversion point Pcorresponding to the eqilbria: solution (E) LiCl·H2O (at 25, 50℃) or LiCl·2H2O (at 0℃) + NaCl + Li2B4O7 · 3H2O and solution (P) + Na2-B4O7·1OH2O NaCl + Li2B4O7·3H2O and the crystallization fields ofborates are much larger than those of chlorides.  相似文献   

9.
The solubilities of the quaternary system Li^+,K^+,Mg2^+//Cl^--H2O were investigated at 348 K via isothermal evaporation.The densities and refractive indices of its equilibrated solution were also determined experimentally.On the basis of the obtained data,the metastable phase diagram,the water content diagram,the diagrams of the density and refractive index against the composition of this quaternary system were constructed.The quaternary system Li^+,K^+,Mg^2+//Cl^--H2O at 348 K belongs to a complex type with the formation of two carnallite double salts,which are potassium carnallite(K-carnallite) and lithium carnallite(Li-carnallite).There are five salts like potassium chloride (KCl),lithium chloride monohydrate(LiCl.H2O),bischofite(MgCl2·6H2O),K-carnallite(KCl·MgCl2·6H2O) and Li-carnallite(LiCl·MgCl2·7H2O),seven unvariant curves named AH3,BH2,CH3,DH1,EH1,H1H2 and H2H3,and three invariant points,namely H1,H2 and H3,included in this metastable phase diagram.Comparisons between the stable phase diagram at 298 K and metastable phase diagram at 348 K of this quaternary system show that all the crystalline forms of the salts are not changed,whereas the crystallization areas of salts are changed significantly with temperature.The scope of KCl crystallization increases from 82% to 95% and that of K-carnallite decreases from 15.80% to 0.32% along with the temperature increasing from 298 K to 348 K,respectively.  相似文献   

10.
王晓妮  张洁等 《中国化学》2003,21(3):270-275
The solubility property of the ZnCl2-Leu-H2O(Leu=L-a-leucine) system at 298.15K in the whole concentration range was investigatey by the semimicro-phase equilibrium method.The corresponding solubility diagram and refractive index diagram were constructed.The results indicated that there was one complex formed in this system.namely,Zn(Leu)Cl2.The complex is congruently soluble in water.Based on Phase equilibrium data,the complex was prepared.Its composition and properties were characterized by chemical analysis,elemental analysis,IR spectra,and TG-DTG.The thermochemical properties of coordination reaction of zinc chloride with L-a-leucine were investigated by a microcalorimeter.The enthalpies of solution of L-a-leucine in water and its zinc complex at infinite dilution and the enthalpy change of solid-liquid reaction wrer determined at 298.15K.The enthalpy change of soild phase reaction and the standard enthalpy of formation of zinc complex were claculated.On the basis of experimental and calculated results,three thermodynamic parameters(the activation enthalpy,the activation entropy and the activation free energy),the rate constant and three kinetic parameters(the activation energy,the preexponential constant and the reaction order) of the reaction,and the standard enthalpy of formation of Zn(Leu)^2 (aq) were obtained.The results showed that the title reaction took place easily at studied temperature.  相似文献   

11.
This paper introduces the functions representing quantitatively the sensitivity of the volume scattering function to the aerosol refractive index, points out the scattering angle regions where volume scattering function is more sensitive to the real part of refractive index or its imaginary part, and analyzes the correlativity between scattering channels. Furthermore, we have analyzed optimum channels of remote sensing of refractive index, and satisfactory inversion results have been obtained when the optimum channels were used in retrieving refractive index.  相似文献   

12.
Co3O4/reduced graphene oxide composites were synthesized via a simple electrochemical method from graphene oxide and Co(NO3)2·6H2O as raw materials.Co3O4 nanoparticles with sizes of around 30-50 nm were distributed on the surface of graphene nanosheets confirmed by scanning electron microscopy and transmission electron microscopy.Electrochemical properties of Co3O4/graphene composite were tested by cyclic voltammetry,galvanostatic charge-discharge,and electrochemical impedance spectroscopy.The Co3O4/reduced graphene oxide composite was used as the pseudocapacitor electrode in the 2 mol/L NaOH aqueous electrolyte solution.The Co3O4/reduced graphene oxide composite electrode exhibited a specific capacitance of 357 F/g at a current density of 0.5 A/g in a three-electrode system.72% of capacitance was retained when the current density increased to 3 A/g.The Co3O4/reduced graphene oxide composite prepared electrodes show a high rate capability and excellent long-term stability.After 1000 cycles of charge and discharge,the capacitance is still maintained 87% at a current density of 1 A/g,indicating that the composite is a oromising alternative electrode material used for supercapacitors.  相似文献   

13.
A hydrodynamic-thermodynamic equation set was set up to reflect the formational mechanism and evolution of the Northern Yellow (Huanghai) Sea cold water mass (NYSCWM) and its density circulation. Appropriate mathematical physical models were established by using some physical postulations. An approximate analytic solution to expound the distributions of temperature and three-dimensional current velocity, which can be used to expound the formational mechanism of the NYSCWM and its density circulation is obtained by using the theory of boundary layer and perturbational analyses.  相似文献   

14.
ALI  A. SABIR  S. SHAHJAHAN HYDER  S. 《中国化学》2006,24(11):1547-1553
Density, viscosity, and refractive index, for glycine, DL-alanine, L-serine and DL-valine have been determined in aqueous solution of 0.05 mol/kg caffeine as a function of amino acid (AA) concentration at 25, 30, 35, and 40 ℃ The density data have been used to compute apparent molar volume. The partial molar volume (limiting apparent molar volume) was obtained by applying the Masson's equation. The viscosity data have been analyzed by means of Jones-Dole equation. The values of Falkenhagen coefficient and Jones-Dole coefficient thus obtained are used to interpret the solute-solute and solute-solvent interactions, respectively. Hydration number was also computed. The transition-state theory was applied to obtain the activation parameters of viscous flow, i.e., free energy of activation per mole of solvent, and solute. The enthalpy and entropy of activation of viscous flow were computed for the system. Refractive index was used to calculate molar refractivity of the mixtures. The results have been interpreted in the light of various interactions occurring between the components of the mixtures under applied experimental conditions.  相似文献   

15.
罗金荣  阮玉忠  林寿 《结构化学》2012,31(2):155-160
In the study, sludge from the aluminum profile factory and kaolin were used as the raw materials. Through adding ZrO2 mineralizer in different contents, Al2-xZrx+yTi1-yO5 and Al4.54Si1.46O9.73 solid solution multiphase material was prepared to effectively inhibit the decomposition of aluminum titanate solid solution and optimize high temperature property of the multiphase material. With XRD and SEM means, crystalline structure and microstructure of each sample were characterized, and properties of each sample were tested. According to experimental results, the optimal addition amount of ZrO2 mineralizer was determined to be 1.5%. Correspondingly, contents for aluminum titanate solid solution, mullite solid solution and α-Al2O3 were 70.3%, 26.8% and 2.9% respectively, bulk density was 3.20 g/cm3, degree of porosity was 5.57%, water absorption rate was 1.74%, and the once thermal shock rupture strength retention rate was 90.52%.  相似文献   

16.
Li–O2 batteries have attracted significant interest in the past decade owing to their superior high specific energy density in contrast to conventional lithium ion batteries.An 8.7-Ah Li–O2 pouch cell with768.5 Wh kg^-1 was fabricated and characterized in this investigation and the factors that influenced the electrochemical performance of the Li–O2 pouch cell were studied.In contrast to coin/Swagelok-type Li–O2 cells,it was demonstrated that the high-loading air electrode,pulverization of the Li anode,and the large-scale inhomogeneity of the large pouch cell are the major reasons for the failure of Li–O2 batteries with Ah capacities.In addition,safety tests of large Li–O2 pouch cells were conducted for the first time,including nail penetration,crushing,and thermal stability.It was indicated that a self-limiting mechanism is a key safety feature of these batteries,even when shorted.In this study,Li–O2 batteries were investigated in a new size and capacity-scale,which may provide useful insight into the development of practical pouch-type Li–O2 batteries.  相似文献   

17.
Anodic polarization behaviors of iron in pure H2SO4 and three mixed acidic solutions, H2SO4 NaCl,H2SO4 NaNO3 and H2SO4 NaCl NaNO3, were investigated. The potentiodynamie sweep curves showed that the current densities rose and dropped irregularly in H2SO4 NaCl solution at the more anodic potentials since the iron surface suffered pitting attack in the solution, but the pitting corrosion was inhibited effectively in the presence of nitrate ions. The surface morphological measurements indicated that pits appeared on the iron surface in H2SO4 NaCl solution and only a few unobvious corrosion spots were observed in H2SO4 NaCl NaNO3 sointian after the iron electrode was potentiostatically polarized at 1.3 V. The oscillatory properties of iron are associated with the susceptlbility of the iron to pitting. In H2SO4 NaCl solution, the regular potentiostatic current oscillations gradually evolved into the irreg-niar current fluctuations due to occurrence of the pitting; whereas in H2SO4 NaCl NaNO3 solution, the current oscillations took place regularly, like the oscillatory behavior in the pure H2SO4 solution. Thus, when the higher the oscillatory fre-quency, the more irregular oscillatory process and the more sensitive to pitting iron occurred.  相似文献   

18.
Kinetics of reaction between Na2S2O3 and peroxide compound ( H2O2 or Na2S2O8) in a batch reactor and in a continuous stirring tank reactor (CSTR) were studied.Steady oscillations in uncatalyzed reactions in a CSTR were first discovered.In Na2S2O3-H2O2-H2SO4 reaction system,Pt potential and pH of higher and lower flow rutes beyond oscillation flow rates were in around the same extreme values.The reaction catalyeed by Cu2+ corsist of the catalyzed oscillation process and the uncatalyzed osciliation one.On the basis of experiment,a reaction mechanism consisting of three stages was put forward.The three stages are H positive-feedback reactions,proton negative-feedba k (uncatalyzed negative-feedback and catalyzed negative-feedback) reactions and transitional reactions.The mechanism is able to explain reasonably the nonlinear chemical phenomena appearing in the thiosulfatc oxidation reaction by peroxide-compounds.  相似文献   

19.
The single toxicity of aniline and its derivatives and the joint toxicity of the binary mixtures of aniline and each of its derivatives with the toxic unit ratios of 1:1, 1:4, 4:1 to photobacterium phosphoreum were determined, respectively. The toxic unit and the additive index were used to evaluate the joint toxicity. The result shows that the joint toxicity of each of the binary mixtures of aniline and each of its derivatives is mainly simple addition of the toxicities of the two compounds. On this basis, the QSAR equation that was built from the single toxicity of aniline was used to predict the toxicity of the derivatives of aniline in the mixtures. Good agreement between the predicted and experimental values was found with R^2=0. 921.  相似文献   

20.
A two-step sintering method was used to prepare Al8.31Si1.91Mg3.78O20 (corundum solid solution)/Al4.8Si1.2O9.6 (mullite solid solution)/Mg2.0Al4.02Si4.98O18 (cordierite solid solution) multiphase material, for the purposes of making these three crystal structures have point defects which could help the particles diffuse and transfer at high temperature, accelerate the sintering efficiently and enhance the material strength as well as the bulk density. The impacts of different formulas on the structure and properties of the multiphase material were investigated. With XRD and SEM analyses, for each sample, the crystal structure and microstructure were characterized, the crystalline phase content and cell parameters were determined with Rietveld Quantification software, and the properties were tested. The comparative optimal formula determined was calcinated chamotte of 80wt% and calcinated sludge of 20wt%; and its corresponding bending strength and retention rate of bending strength after a thermal shock were 29.74 MPa and 80.15%, respectively.  相似文献   

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