Na^＋,K^＋,Mg^2＋∥Cl^—,SO4^2——H2O五元体系15℃介稳相图研究

得到Na^ ,K^ ,Mg^2 ∥Cl^-,SO4^2--H2O五元体系15℃时的介稳溶解度数据，绘制了该体系在15℃的介稳相图，共有9个为氯化钠所饱和结晶区域：氯化钾，硫酸钠，钾钠芒硝，软钾镁矾，白钠镁矾，光卤石，七水硫酸镁，六水硫酸镁和水氯镁石。所得15℃介稳相图和Van‘t Hoff稳定相图比较有较大区别；在15℃介稳相图中钾镁矾，钾盐镁矾以及五水硫酸镁和四水硫酸镁结晶区域消失，而软钾镁矾结晶区域显著扩大。比较作者所作该五元体系15℃，25℃及35℃介2稳相图，发现软钾镁矾（包括钾镁矾）相区以25℃时最大，35℃时最小，随温度升高，钾钠芒硝结晶相区依次向KCl相区平行移动，导致KCl相区缩小，Na2SO4相区扩大，随温度升高相应点的钠含量和水含量依次减小。     

四元交互体系Li^＋,k^＋／Cl,SO^2—4—H2O50,75℃相平衡研究

采用等温溶解平衡法测了四元交互体系Ｌｉ＾＋，Ｋ＾＋／Ｃｌ，ＳＯ＾２－４－Ｈ２Ｏ５０，７５℃平衡溶液的物化物质（密度，粘度，折光率），该四元交互体系５０，７５℃的溶解度等温图有５个相区：即Ｌｉ２ＳＯ４．Ｈ２Ｏ，ＫＬｉＳＯ４，ｋｃｌ，ｋ２ｓｏ４，ｌＩｃＬ．Ｈ２Ｏ，７条单变量曲线，３个共饱点，其中ＬｉＳＯ４．Ｈ２Ｏ＋ＫＣＬ＋ＬｉＣｌ．Ｈ２Ｏ为一致零变量点，用我们以往提出的经验公式处理了平衡溶液的密度和折     

SrO—Al2O3—SiO2：Eu^3＋,Bi^3＋发光体的溶胶—凝胶法合成

制备无机固体材料大都采用高温固相反应,1971年Dislich报导了用溶胶-凝胶法制备多组份固体材料。近年来,有报导利用此法研制玻璃、玻璃陶瓷和陶瓷。我们在过去工作的基础上,合成了SrO-Al_2O_3-SiO_2:Eu~(3 ),Bi~(3 )发光体,研究了从凝胶至发光晶体的转变过程、Eu~(3 )和Bi~(3 )在SrO-Al_2O_3-SiO_2基质中的发光性质以及Bi~(3 )对 EU~(3 )的能量传递。     

四元交互体系Li^＋,K^＋／cL^—,CO^2—3—H2O在298K时相平？…

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.     

Isothermal Evaporation of Quaternary System Li^＋, K^＋, Mg^2＋//Cl^--H2O at 348K

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.     

SrB4O7中Sm^2＋的发光及Eu^2＋,Sm^2＋之间的能量传递

对SrB_4O_7:Sm~(2+)发光特性的研究发现,在液氮温度下只有来自~5D_0能级的发射,而室温时又出现了~5D_1的发射,高温时同时观察到~5D_0、~5D_1的线状发射和5d→4f跃迁的带状发射,利用电子-声子耦合理论讨论了这些变化,并分析了Eu~(2+)→Sm~(2+)的能量传递现象。     

溶胶—凝胶合成（Mg,Ca）O—SiO2：Eu^3＋,Bi^3＋发光体及其发光行为

以Ｍｇ（ＮＯ３）２，Ｃａ（ＮＯ３）２，Ｅｕ（ＮＯ３）３，Ｂｉ（ＮＯ３）３和Ｓｉ（ＯＣ２Ｈ５）４为反应物，采用溶胶－凝胶法，在比较低的温度，首次合成０．７０１ｍｏｌＭｇＯ－０．１７５ｍｏｌＣａＯ－１．２５ｍｏｌＳｉＯ２：０．０６ｍｏｌＥｕ＾３＋，０．００２ｍｏｌＢｉ＾３＋（加入Ｌｉ＾＋作为电荷补偿剂）发光体，得到了最佳合成条件，研究了由溶胶向凝胶转变和凝胶向发光晶体的转变过程，探讨了发光体在不同激光     

Ca2B2O5中Ce^3＋,Mn^2＋的发光与能量传递

本文研究了Ca_2B_2O_5中Ce~(3+)、Mn~(2+)光致发光的性质与其含量的关系,并讨论了Ce~(3+)对Mn~(2+)的能量传递机理.     

Mg^2＋，K^＋//Cl^-，B4O7^2——H2O四元体系288K固液相平衡

采用等温溶解平衡法研究了288K时Mg^2＋,K^＋//Cl^-,B4O7^2--H2O四元体系的相平衡关系,测定该体系在288K时平衡液相的溶解度和密度．依据实验测定的平衡溶解度数据及对应的平衡固相,绘制了该四元体系的平衡相图以及其密度一组成图．研究结果表明,四元体系Mg^2＋,K^＋//Cl^-,B4O7^2--H2O288K时的固液相平衡实验中,有复盐KCl·MgCl2·6H2O生成,平衡相图中有3个共饱点,7条单变量曲线,5个结晶区,对应的平衡固相分别为MgB4O7·9H2O,K2B4O7·4H2O,KCl,MgCl2·6H2O,KCl·MgCl2·6H2O．简要讨论了实验结果．     

五元体系K2^2＋,Mg^2＋／／Cl2^2—,SO4^2——CO（NH2）2—H2O及其边界四元体系MgSO4—MgCl2—CO（NH2）2—H2O在25℃时的等温溶度研究

报道了五元体系K_2~(2 ),Mg~(2 )//Cl_2~(2-),SO_4~(2-)-CO(NH_2)_2-H_2O在脲不饱和区及其边界四元体系MgSo_4-MgCl_2-CO(NH_2)_2-H_2O在25℃时的等温溶度研究结果,绘制了体系等温溶度的盐分组成图、水量图以及饱和溶液的折光率-组成图.五元体系在脲的参与下,交互反应K_2Cl_2 MgSO_4→K_2SO_4 MgCl_2向有利于生成硫酸钾和软钾镁矾K_2SO_4·MgSO_4·6H_2O(pic.)的方向进行,这两者的相区较无脲时明显增大。     

Y2O3—Nb2O5—B2O3：Eu^3—.Bi^3＋的磷光体的晶体结构与光…

采用常规固相反应于１２００℃下制备了具有褐钆铌矿结构的Ｙ２Ｏ３、Ｎｂ２Ｏ５．ｂ２ｏ３（ｙ０．９３Ｅｕ０．０７）２Ｏ３．Ｎｂ２ｏ５．Ｂ２Ｏ３和（×０。９１Ｅｕ０．０７Ｂｉ０．０２）２Ｏ３．Ｎｂ２Ｏ５．Ｂ２Ｏ３等磷光体，研究了它们的发光性质。结果表明，在２６８ｎｍ紫外光激发下，由于ＮｂＯ４基团于４１０ｎｍ处发生＾１Ｔ→＾１Ａ１跃迁，致使Ｙ２Ｏ５．Ｎｂ２Ｏ５．Ｂ２Ｏ３呈现更亮的紫外发射。体系中Ｂ２Ｏ３可     

LaC4^n（n=—2,—1,0,＋1,＋2）分子簇的结构与稳定性

本文用密度泛函方法研究了ＬａＣ４ｎ（ｎ＝－２,－１,０,＋１,＋２）分子簇的结构与稳定性。振动频率分析表明,在所提出的九个构型中,当ｎ＝－２,０,＋１,＋２时,稀土位于碳环上最稳定,而当ｎ＝－１时,尽管稀土位于碳环上能量最低,但没有找到稳定的构型,我们的结果还指出,稀土元素是分子簇中对外部环境最敏感的部位,即最具有反应活性