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1.
测定了RbNO3-C2H5OH-H2O 体系在25 ℃和50 ℃的等温平衡溶解度及饱和液的性质(密度和折光率). 绘制了相图, 计算了盐析率, 评价了盐析效果. 用经验公式分别对溶解度、密度和折光率进行了关联, 效果良好. 体系没有产生分层现象, 得到的平衡固相皆为无水铷盐, 没有新化合物或水合物生成.  相似文献   

2.
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   

3.
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   

4.
房春晖  李冰  李军  王庆忠  宋彭生 《化学学报》1994,52(10):954-959
用等温溶解平衡法研究了四元体系Li^+,K^+,Mg^2^+/SO~4^2^--H~2O 25℃溶解度,测定了饱和溶液的密度,粘度,折光率,pH和电导率等物化性质. 四元体系相图由六条溶解度分枝线和五个结晶区构成,分别对应于原始组分和复盐Li~2SO~4·K~2SO~4,K~2SO~4·MgSO~4·6H~2O,没有发现新的复盐或固溶体, 也没有发生原始组分的脱水作用,用现代电解质溶液理论-Pitzer模型校验该体系的溶解度测定值, 结果令人满意  相似文献   

5.
用等温溶解平衡法研究了四元体系Li~ ,K~ ,Mg~(2 )/So_4~(2-)-H_2O25℃溶解度,测定了饱和溶液的密度、粘度、折光率、pH和电导率等物化性质.四元体系相图由六条溶解度分枝线和五个结晶区构成,分别对应于原始组分和复盐Li_2SO_4·K_2SO_4,K_2SO_4·MgSO_4·6H_2O,没有发现新的复盐或固溶体,也没有发生原始组分的脱水作用.用现代电解质溶液理论——Pitzer模型校验该体系的溶解度测定值,结果令人满意.  相似文献   

6.
采用等温溶解平衡法测定了四元交互体系Li~+,K~+/Cl~-,75℃的溶解度和平衡溶液的物化性质(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Li_2SO_4·H_2O,KLiSO_4,KCl,K_2SO_4,LiCl·H_2O,7条单变量曲线,3个共饱点,其中Li_2O_4·H)2O+KCl+LiCl·H_2O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光率,由所测得的溶解度数据,求得了高温和高锂浓度下的电解质溶液Pitzer模型的离子相互作用参数。计算了各平衡溶液中盐的活度和水的活度。还计算了该四元交互体系25℃的溶解度,考察了Pitzer电解质溶液理论在水-盐溶解度计算中的应用。  相似文献   

7.
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   

8.
测定了四元体系KCl-K2SO4-CO(NH2)2-H2O及边界三元体系K2SO-CO(NH2)2-H2O在25℃时的溶度及饱和溶液密度值和折光率,绘制了相应的溶度图及相应的组成-性质图.测定并绘制了该四元体系K2SO4单饱区的溶度面、折光率面和密度面图.两个体系的溶度图均属于低共饱型,平衡固相为组份化合物.  相似文献   

9.
25℃时MgCl2-H2O-酰胺(DMA,DMF, FA)三元体系的相平衡   总被引:3,自引:0,他引:3  
本文报道三元体系MgCl2-H2O-DMA(I), MgCl2-H2O-DMF(II)和MgCl2-H2O-FA(III)25℃时的溶解度与饱和溶液的折光率、密度和粘度等物理化学性质, 给出了这些体系的溶度图和性质图。其中体系I和III属首次报道, 体系II的结果较好地解释文献中存在的分歧。  相似文献   

10.
采用等温蒸发平衡法研究了四元体系K2B4O7-Na2B4O7-Li2B4O7-H2O15℃时的介稳相平衡及平衡液相的物化性质(密度,粘度,电导率,折光率,pH)。根据实验数据绘制了相图,相图中有一个共饱点E,三条单变度曲线E3F,E2F,E1F;三个平衡固相分别为:K2B4O7•4H2O,Na2B4O7•10H2O和Li2B2O4•16H2O;硼酸钾具有最大溶解度,硼酸钠具有最小溶解度。同时,根据试验数据绘制了组成-物化性质关系图,从图可见溶液的密度,粘度和折光率均随着溶液浓度的增大而逐渐增大,在共饱和点F处达到最大值,而溶液的pH值和电导率却随着溶液浓度的增大呈总体下降的趋势。  相似文献   

11.
Scandium magnesium gallide, Sc2MgGa2, and yttrium magnesium gallide, Y2MgGa2, were synthesized from the corresponding elements by heating under an argon atmosphere in an induction furnace. These intermetallic compounds crystallize in the tetragonal Mo2FeB2‐type structure. All three crystallographically unique atoms occupy special positions and the site symmetries of (Sc/Y, Ga) and Mg are m2m and 4/m, respectively. The coordinations around Sc/Y, Mg and Ga are pentagonal (Sc/Y), tetragonal (Mg) and triangular (Ga) prisms, with four (Mg) or three (Ga) additional capping atoms leading to the coordination numbers [10], [8+4] and [6+3], respectively. The crystal structure of Sc2MgGa2 was determined from single‐crystal diffraction intensities and the isostructural Y2MgGa2 was identified from powder diffraction data.  相似文献   

12.
13.
On Dialkali Metal Dichalcogenides β-Na2S2, K2S2, α-Rb2S2, β-Rb2S2, K2Se2, Rb2Se2, α-K2Te2, β-K2Te2 and Rb2Te2 The first presentation of pure samples of α- and β-Rb2S2, α- and β-K2Te2, and Rb2Te2 is described. Using single crystals of K2S2 and K2Se2, received by ammonothermal synthesis, the structure of the Na2O2 type and by using single crystals of β-Na2S2 and β-K2Te2 the Li2O2 type structure will be refined. By combined investigations with temperature-dependent Guinier-, neutron diffraction-, thermal analysis, and Raman-spectroscopy the nature of the monotropic phase transition from the Na2O2 type to the Li2O2 type will be explained by means of the examples α-/β-Na2S2 and α-/β-K2Te2. A further case of dimorphic condition as well as the monotropic phase transition of α- and β-Rb2S2 is presented. The existing areas of the structure fields of the dialkali metal dichalcogenides are limited by the model of the polar covalence.  相似文献   

14.
15.
[(n‐Bu)2Sn(O2PPh2)2] ( 1 ), and [Ph2Sn(O2PPh2)2] ( 2 ) have been synthesized by the reactions of R2SnCl2 (R=n‐Bu, Ph) with HO2PPh2 in Methanol. From the reaction of Ph2SnCl2 with diphenylphosphinic acid a third product [PhClSn(O2PPh2)OMe]2 ( 3 ) could be isolated. X‐ray diffraction studies show 1 to crystallize in the monoclinic space group P21/c with a = 1303.7(1) pm, b = 2286.9(2) pm, c = 1063.1(1) pm, β = 94.383(6)°, and Z = 4. 2 crystallizes triclinic in the space group , the cell parameters being a = 1293.2(2) pm, b = 1478.5(4) pm, c = 1507.2(3) pm, α = 98.86(3)°, β = 109.63(2)°, γ = 114.88(2)°, and Z = 2. Both compounds form arrays of eight‐membered rings (SnOPO)2 linked at the tin atoms to form chains of infinite length. The dimer 3 consists of a like ring, in which the tin atoms are bridged by methoxo groups. It crystallizes triclinic in space group with a = 946.4(1) pm, b = 963.7(1) pm, c = 1174.2(1) pm, α = 82.495(6)°, β = 66.451(6)°, γ = 74.922(6)°, and Z = 1 for the dimer. The Raman spectra of 2 and 3 are given and discussed.  相似文献   

16.
17.
Summary The ability of [MoS4]2–, anions to be used as ligands for transition metal ions has been widely demonstrated, especially with Fe2+. The present study has been restricted to linear complexes such as (NEt4)2 [Cl2FeS2MoS2] and (NEt4)2[Cl2FeS2MoS2FeCl2]. Their electrochemical properties are described: upon electrochemical reduction, these compounds yield MoS2, as a black precipitate, and an iron complex in solution, assumed to be [SFeCl2]2–. The electrochemical reduction goes through two electron transfers, coupled with the breakdown of the molecular skeleton: a DISPl and an ECE mechanism. Depending on the solvent, the following equilibrium may be observed: [Cl4Fe2MoS4]2–[Cl2FeMoS4]2–+FeCl2. The equilibrium constant, KD, was evaluated by differential pulse polarography. KD is tightly related to the donor number of the solvent.  相似文献   

18.
The structures of the hypophosphites KH2PO2 (potassium hypophosphite), RbH2PO2 (rubidium hypophosphite) and CsH2PO2 (caesium hypophosphite) have been determined by single‐crystal X‐ray diffraction. The structures consist of layers of alkali cations and hypophosphite anions, with the latter bridging four cations within the same layer. The Rb and Cs hypophosphites are isomorphous.  相似文献   

19.
TG and DTA studies on Me3SnO2PCl2, Me2Sn(O2PCl2)2 and Ph3SnO2PCl2 were carried out under dynamic argon atmosphere. The results show that the decomposition proceeds in different stages leading to the formation of Sn3(PO4)2 as a stable product. This compound was characterized by IR spectroscopy. Decomposition schemes involving reductive elimination reactions were proposed.  相似文献   

20.
Me2Sn(O2PPh2)2 ( 1 ), Ph2Pb(O2PMe2)2 ( 2 ), and Ph2Pb(O2PPh2)2 ( 3 ) have been synthesized by the reactions of Me2SnCl2 or Ph3PbCl with the corresponding diorganophosphinic acid in methanol. X‐ray diffraction studies show that the diorganophosphinate groups behave as double bridges between the metal atoms leading to polymeric ring‐chain structures with M2O4P2 (M = Pb, Sn) eight‐membered rings. The organic groups bonded to the metal atoms are in trans‐position in the resulting octahedral arrangement around the metal atoms. The IR and the mass spectra were reported and discussed.  相似文献   

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