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1.
The data of solubilities, densities and refractive indices of rubidium chloride or cesium chloride in the system CEHsOH-H2O were measured by using a simple accurate analytical method at different temperatures, with mass fractions of ethanol in the range of 0 to 1.0. In all cases, the presence of ethanol significantly reduced the solubility of rubidium chloride and cesium chloride in aqueous solution. The solubilities of the saturated solutions were fitted via polynomial equations as a function of the mass fraction of ethanol. The CsC1-C2H5OH-H2O ternary system appeared in two liquid phases: alcoholic phase and water phase, when the mass fractions of ethanol were in the range of 10.37% to 49.59% at 35 ℃. Density and refractive index were also determined for the same ternary systems with varied unsaturated salt concentrations. Values for both experiment and theory were correlated with the salt concentrations and proportions of alcohol in the solutions. The equations proposed could also account for the saturated solutions.  相似文献   

2.
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   

3.
In order to improve the tensile properties of poly(ethylene terephthalate)(PET), we used the direct esterification method to synthesize PET in a home-made facility, and a certain amount of ethylene glycol (EG), one of the two starting monomers, was substituted by glycerin (GE). Four PETs with different GE contents were prepared to investigate the effect of GE on the crystallization and tensile properties of the prepared copolyester. The results showed largely improved tensile properties and increased crystallization temperature due to the possible crosslinking structure in PET by using a small amount of GE.  相似文献   

4.
Solubilities of ternary systems Li+,K+/SO42--H2O (1) and Li+,Mg2+/SO42-H2O (2) were investigated by isothermal method at 25℃. Physico-chemical properties of solutions, such as density, refractive index, viscosity, conductivity and pH, were determined. Phase diagram of the system (1) consists of three solubility branches and three crystallization fields corresponding to K2SO4, Li2SO4.H2O and LiKSO4. LiKSO4 is an incongruent compound, and its transition point is estimated graphically to be 45.5-46.0℃. No solid solution of LiKSO4 with Li2SO4.H2O was found in the system. The system (2) is a simple eutonic type. Pitzer model of electrolyte solution was used to check the obtained solubilities. Data comparison gives good agreement. Two equations were used to correlate density, refractive index of the solution with its composition. Differences between measured and calculated values are less than 0.6% for density, 0.15% for the latter.  相似文献   

5.
The densities (ρ), ultrasonic speeds (v), and refractive indices (n) of binary mixtures of styrene (STY)with m-, o-, or p-xylene, including those of their pure liquids, were measured over the entire composition range at the temperatures 298.15, 303.15, 308.15, and 313.15 K. The excess volumes (VE), deviations in isentropic compressibilities(△ks), acoustic impedances (△Z), and refractive indices (△n) were calculated from the experimental data. Partial molar volumes (V0φ,2) and partial molar isentropic compressibilities (K0φ,2) of xylenes in styrene have also been calculated. The derived functions, namely, VE, △ks, △Z, △n, V0φ,2, and K0φ,2 were used to have a better understanding of the intermolecular interactions occurring between the component molecules of the present liquid mixtures. The variations of these parameters suggest that the interactions between styrene and o-, m-, or p-xylene molecules follow the sequences: p-xylene>o-xylene>m-xylene. Apart from using density data for the calculation of VE, excess molar volumes were also estimated using refractive index data. Furthermore, several refractive index mixing rules have been used to estimate the refractive indices of the studied liquid mixtures theoretically. Overall, the computed and measured data were interpreted in terms of interactions between the mixing components.  相似文献   

6.
《天然气化学杂志》2012,(4):452-458
A series of CaO samples were prepared by calcination of commercially available and synthesis of calcium salt precursors such as calcium acetate,carbonate,hydroxide and oxalate etc.CaO samples were found to be effective for the epoxidation of styrene using hydrogen peroxide as an oxidant in the presence of acetonitrile.To determine the influence of the physicochemical properties and surface basicity on the catalytic activity,the prepared CaO samples were characterized using thermogravimetry(TG),X-ray diffraction(XRD),scanning electron microscopy(SEM),N2-adsorption and temperature-programmed desorption of CO2(CO2-TPD).The results indicate that the amounts of very strong basic sites and high basicity strength on CaO sample are key factors for its excellent catalytic performance.In contrast,the surface area,porosity and the surface structure of CaO sample have a relatively minor effect on the catalytic activity.CaO sample,obtained by the decomposition of Ca(OH)2,prepared by precipitating calcium nitrate with sodium hydroxide in ethylene glycol solution,exhibits the highest amount of very strong basic sites and stronger strength of basic sites,and therefore it catalyses the epoxidation of styrene with the highest rate among the tested CaO samples.Under the selected reaction conditions,the selectivity of 97.5% to styrene oxide at a conversion in excess of 99% could be obtained.  相似文献   

7.
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   

8.
三元添加剂水溶液体系中金属银粒子的形貌控制合成   总被引:1,自引:0,他引:1  
Single-crystal silver hollow disks and nanorods were prepared by controlled synthesis in a mixed aqueous solution of ternary additives (poly(ethylene glycol) (PEG), methacrylic acid (MAA) and sodium dodecylsulfate (SDS)). The Products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy(SEM). SEM studies suggest that the well-separated silver microdisks with diameter of 2~3 μm and thicknesses of about 200 nm were obtained. The corresponding selected area electron diffraction (SEAD) reveals the single-crystal nature of these hollow silver disks.  相似文献   

9.
In this paper, the Gladstone-Dale ionic refractivities (GDIR values) are calculated onthe basis of the K values given by Mandarino and/or the author. The effects of the elec-tron shell configuration of ions on the refractive properties of minerals are discussed. Theconclusions are as follows: (1) The refractive indices of the compounds consisting of Ne-type ions are linearlyrelated with their densities. (2) The ionic refractivities of the inert gas-type ions are different from those of 18electron-type ions in their variation relationship. (3) The ionic refractivities of ⅠA, ⅡA, ⅢA, ⅣA, ⅤA and ⅥA Groups in the periodictable increase linearly with increasing atomic number. (4) The two-humped curves are found for the ionic refractivities of the first transitionelements. (5) Because of the lanthanum series contraction, the ionic refractivities of rare earthelements decrease with increasing atomic number.  相似文献   

10.
Polyoxymethylene (POM)/elastomer/filler ternary composites were prepared, in which thermoplastic polyurethane (TPU) and inorganic filler, namely, CaCO3, were used to achieve balanced mechanical properties of POM. The dispersion and phase morphology of POM/elastomer/filler composites were found to depend largely on processing method, CaCO3 content in masterbatch and the filler size. Two processing methods were employed to prepare POM/elastomer/filler ternary composites. One is called the one-step method, in which elastomer and the filler directly melt blended with POM matrix. The other is called the two-step method, in which the elastomer and the filler were mixed to get masterbatch first, which was then melt blended with pure POM of different content. The effect of phase morphology and processing method on impact strength was investigated. It was found that the two-step method results in an increase in impact strength but not for the one-step method. Additionally, the impact strength of POM ternary composites decreases with the increase in the size of CaCO3 particles.  相似文献   

11.
The solubilities, densities and refractive indices data for the four ternary systems ethylene glycol + MCl + H2O (M = Na, K, Rb, Cs) at different temperatures were measured, with mass fractions of ethylene glycol in the range of 0 to 1.0. In all cases, the presence of ethylene glycol significantly reduces the solubility of the salts in aqueous solution. The experimental data of density, refractive index and solubility of saturated solutions for these systems were correlated using polynomial equations as a function of the mass fraction of ethylene glycol. On the other hand, the refractive index and density of unsaturated solutions was also determined for the four ternary systems with varied unsaturated salt concentrations. Values for both the properties were correlated with the salt concentrations and proportions of ethylene glycol in the solutions.  相似文献   

12.
本文通过简单精确的分析方法测定了硝酸铷在水、水+甲醇以及在水+乙醇中在不同温度下的溶解度。在甲醇和乙醇存在的情况下,硝酸铷在水的溶解度都明显降低。通过四参数方程对试验数据拟和,取得了满意的结果。同时也测定了三元体系在“饱和”和“非饱和”状态下的折光率,并对折光率和醇及盐的浓度进行关联。  相似文献   

13.
采用自制的相平衡研究装置, 测定了RbBr-CH3OH/C2H5OH-H2O和CsBr-CH3OH/C2H5OH-H2O四个三元体系在25、35、45 ℃三个温度下的平衡溶解度;同时得到了四个三元体系饱和溶液中不同盐浓度下的折光率数据. 实验结果表明,在所有的体系中, 随着甲醇或乙醇质量分数的增加, RbBr和CsBr 在水中的溶解度逐渐降低; 并且折光率也逐渐减小. 用经验关联方程对溶解度进行了拟合, 同时给出了CH3OH 和C2H5OH 分别对RbBr和CsBr的盐析率曲线.  相似文献   

14.
RbBr/CsBr-CH3OH/C2H5OH-H2O三元体系的溶解度   总被引:1,自引:0,他引:1  
采用自制的相平衡研究装置,测定了RbBr-CH_3OH/C_2H_5OH-H_2O和CsBr-CH_3OH/C_2H_5OH-H_2O四个三元体系在25、35、45℃三个温度下的平衡溶解度;同时得到了四个三元体系饱和溶液中不同盐浓度下的折光率数据.实验结果表明,在所有的体系中,随着甲醇或乙醇质量分数的增加,RbBr和CsBr在水中的溶解度逐渐降低;并且折光率也逐渐减小.用经验关联方程对溶解度进行了拟合,同时给出了CH_3OH和C_2H_5OH分别对RbBr和CsBr的盐析率曲线.  相似文献   

15.
三元体系MgCl2-CO(NH2)2-H2O在25℃时的等温溶度与新相研究   总被引:3,自引:0,他引:3  
测定了25℃时三元体系MgCl2-CO(NH2)2-H2O的等温溶度及饱和溶液的折光率和密度,且绘制成溶度图和性质-组成图.在三元体系内形成2个三元化合物新相:MgCl2·CO(NH2)2·4H2O(记作A)和Mgcl2·4CO(NH2)2·2H2O(记作B),B为新化合物.三元体系的溶度图由4支单饱和线[对应单饱和固相为MgCl2·6H2O、三元化合物A和B、CO(NH2)2]组成,这4支单饱和线两两交于3个三元无变点[对应双饱和固相为MgCl2·6H2O+A、A+B、B+CO(NH2)2].  相似文献   

16.
系统研究了1,2-丙二醇+MCl (M=Na, K, Rb, Cs)+H2O三元体系在298.15 和308.15 K时的等温相平衡. 采用硝酸汞滴定法测定了体系中无机盐的含量, 采用安东帕RXA170 折光率仪及DMA4500 密度计测定了所有体系的折光率和密度数值. 报道了1,2-丙二醇质量分数从0增加到0.9过程中饱和及不饱和三元溶液体系的等温溶解度、密度和折光率数据. 实验结果发现, 随着1,2-丙二醇的不断加入, 饱和溶液的溶解度和密度均呈现出减小的趋势, 而折光率的变化则呈现出相反的趋势. 采用经验方程关联了不同醇水比条件下不饱和溶液的密度和折光率实验数据, 获得了较为理想的拟合结果. 本研究的开展充实了碱金属盐在混合溶剂中的热力学数据, 为相关溶液化学研究奠定了基础.  相似文献   

17.
Solid-liquid phase equilibria of the two ternary systems (NaCl+SrCl2+H2O) and (KCl+SrCl2+H2O) at T=288.15 K and p=0.1 MPa were studied using the isothermal dissolution equilibrium method. Solubilities of the equilibrium liquid phase were determined, and the solids were also investigated by the Schreinemaker method of wet residues. In the ternary system (NaCl+SrCl2+H2O) at 288.15 K, there is one invariant point corresponding to (NaCl+SrCl2·6H2O) and two crystallization regions corresponding to NaCl and SrCl2·6H2O. The crystallized area of SrCl2·6H2O decreased with the increasing temperature, while that of NaCl increased slightly. In the ternary system (KCl+SrCl2+H2O) at 288.15 K, there is one invariant point(KCl+SrCl2·6H2O) and two crystallization regions corresponding to KCl and SrCl2·6H2O. Both systems belong to a simple eutectic type, and neither double salts nor solid solutions were formed. On the basis of Pitzer-Harvie-Weare model, the solubilities of the two systems at 288.15 K were demonstrated. A comparison showed that the calculated solubilities agreed well with the experimental data.  相似文献   

18.
The effect of the amount of precipitant ammonia on the Cu0/Cu+ratio of Cu/Si O2 prepared by the deposition–precipitation method is investigated. Species at different preparation stages, resulted from the amount of ammonia used, are identified by the XRD and FTIR techniques. Chrysocolla together with either copper nitrate hydroxide or copper hydroxide coexist in the uncalcined catalysts. Upon calcination, the latter two species are converted to Cu O particles while chrysocolla remains. Following reduction, Cu O is transformed to metallic Cu and chrysocolla is converted to Cu2 O. The value of Cu0/Cu+ratio can be evaluated using the peak areas in their TPR profiles. Hydrogenation of dimethyl oxalate(DMO) to ethylene glycol(EG) shows that the selectivity of EG depends on the Cu0/Cu+ratio. Catalyst prepared with the addition of ammonia solution at n(NH3)/n(Cu2+) = 0.9 for precipitation–deposition gains a more suitable Cu0/Cu+ratio upon reduction and thus has a higher selectivity for EG.  相似文献   

19.
安替比林及其4位取代衍生物是较强的配位剂,可与不同的稀土盐作用生成组成各不相同的配合物,为了进一步探讨安替比林的衍生物对稀土离子的配位作用,我们研究了以4-一氯乙酰基安替比林(4-ClCH2COAP)为配体与硝酸镧或氧化镧的三元水盐体系。  相似文献   

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