PHASE DIAGRAM OF PrCl_3-SrCl_2-CaCl_2 SYSTEM

Five fields corresponding to the primary crystallization of PrCl_3,Sr_3PrCl_9,α(SrCl_2,CaCl_2),α_1(CaCl_2,SrCl_2)and α_2(SrCl_2,CaCl_2)respectively,six univariant lines relatedto the secondary crystallization,one ternary eutectic(48.0 wt-％ PrCl_3,23.5 wt-％ SrCl_2;590℃)and ternary peritectic point(45.5 wt-％ PrCl_3,24.5 wt-％ SrCl_2;614℃)were determined by DTA.Attempts were also made to explore the rule governing thealteration in the phase diagram containing rare earth chloride,formation of compoundand its stability by means of polarization and counter-polarization.     

PHASE DIAGRAM OF TERNARY SYSTEM PrCl_2-CaCl_2-MgCl_2

Three surfaces corresponding to the primary crystallization of PrCl_3,CaCl_2 andMgCl_2 respectively,3 univariant curves related to the secondary crystallization and a ternaryeutectic(44.8 wt-% PrCl_3,31.8 wt-% CaCl_2,546℃)were found in systemPrCl_3-CaCl_2-MgCl_2 by means of DTA.A reaction occurs in this system:L=PrCl_3+CaCl_2+MgCl_2.     

PHASE DIAGRAMS OF SYSTEMS SmCl_3-CaCl_2 AND SmCl_3-LiCl

The phase diagrams of binary systems SmCl_3-CaCl_2 and SmCl_3-LiCl were determined byDTA and X-ray diffraction analysis.The system SmCl_3-CaCl_2 is of a simple eutectic typewith eutectic point of 55.8mol-% SmCl_3 at 545℃.The system SmCl_3-LiCl is of the typewith incongruent melting phase 2SmCl_3·LiCl at peritectic point 434℃ and with eutecticpoint of 31.5 mol-% SmCl_3 at 395℃.     

A SIMPLIFIED SUBREGULAR SOLUTION MODEL DESCRIBING THE ACTIVITES OF MgCl 2 IN BOTH KCl MgCl 2 LiCl AND CaCl 2 MgCl 2 NaCl MOLTEN SALT SYSTEMS

１．ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅａｃｔｉｖｉｔｉｅｓｏｆＭｇＣｌ２ｉｎｔｈｅＬｉＣｌＭｇＣｌ２ＫＣｌａｎｄＣａＣｌ２ＭｇＣｌ２ＮａＣｌｍｏｌｔｅｎｓａｌｔｅｌｅｃｔｒｏｌｙｔｅｓａｒｅａｎｉｍｐｏｒｔａｎｔｐａｒａｍｅｔｅｒｔｏｔｈｅｅｌｅｃｔｒｏｌｙｔｉｃｐｒｏｄｕｃｔｉｏｎｏｆｍａｇｎｅｓｉｕｍ．ＬｉＣｌａｎｄＫＣｌｃａｎｏｂｖｉｏｕｓｌｙｉｍｐｒｏｖｅｔｈｅｐｒｏｐｅｒｔｉｅｓｏｆｔｈｅｅｌｅｃｔｒｏｌｙｔｉｃｓｏｌｕｔｉｏｎ．ＮａＣｌａｎｄＣａＣｌ２ａｒｅｔｈｅｍａｊｏｒｃｏｍ…     

Synthesis of Ni3Al intermetallic powder in eutectic molten salts

The powders of Ni₃Al intermetallic compounds were simply and economically synthesized by the chemical reaction in the various molten salts systems. In the relatively low temperature ranges, we studied to synthesize Ni₃Al intermetallic powders from Al and NiCl₂ in five kinds of eutectic molten salts by varying the reaction time and mole ratio of reactants. Ni₃Al intermetallic powders could be synthesized in AlCl₃–NaCl (63:37 in mol%), AlCl₃–NaCl–KCl (66:20:14 mol%), NaCl–KCl (50:50 mol%) and MgCl₂–NaCl–KCl (50:30:20 mol%) systems. However, it was impossible to separate the Ni₃Al powders from MgCl₂–NaCl–KCl (50:30:20 mol%) system. The Ni₃Al powders could not be synthesized in AlCl₃–NaCl (50:50 mol%) molten salt. The obtained powders were uniformly sub-micrometer sized. The reaction temperature at 500 °C, the reaction time for 3 h and the mole ratio of NiCl₂/Al=1.3 were the optimum conditions for synthesis of Ni₃Al intermetallic powders in AlCl₃–NaCl (63:37 mol%) molten salt.     

PHASE DIAGRAM OF SYSTEM NdCl_3-LiCl-KCl

The phase diagram of system NdCl_3-LiCl-KCl has been investigated by DTA.Six surfacescorresponding to the prhnary crystallization of NdCl_3,LiCl,KCl,γ-KCl·NdCl_3,β-3KCl·NdCl_3 and 2KCl·NdCl_3 respectively,eleven univariant lines related to the sec-ondary crystallization,two ternary eutectics E_1(70.5wt-% NdCl_3+8.0wt-% KCl,360℃)and E,(5.0wt-% NdCl_3+ 53.0wt-% KCl,355℃)and one ternary peritectic P(67.0wt-% NdCl_3+10.0wt-% KCl,375℃)were found.It is also chtrified that this studyon the system NdCl_3- KCl differs from previous work in the two transition temperatures:e_1(77.0 wt-% NdCl_3,484℃),e_2(40.0wt-% NdCl_3,620℃),p(70.0wt-%NdCl_3,610℃),3KCl·NdCl_3(690℃)and two reactions:α-3KGl·NdCl_3β-3KGl·NdCl_3 (355℃)β-SKGl·NdCl_3γ-3KCl·NdCl_3 (450℃)The eutectic point e_5(31.0wt-%LiCl,460C)is determined for the pseudobinary system3KCl·NdCl_3—LiCl.     

DETERMINATION OF PrCl_3-NaCl-LiCl PHASE DIAGRAM

本文用差热分析法重新测定了组成PrCl_3-NaCl-LiCl三元系的三个侧边二元系相图,测定了该三元系中6个不同组成的变温截面,从而构筑了PrCl_3-NaCl-LiCl三元相图。该三元系由分别对应于PrCl_3,NaCl,2NaCl·LiCl,NaCl·LiCl和LiCl的5个液相面,7条二次结晶线,两个转熔点和一个共晶点构成。转熔点和共晶点的温度和组成分别为:P_1(416℃,30.3mol％NaCl,44.2mol％LiCl,25.5mol％PrCl_3);P_2(409℃,25.0mol％NaCl,50.0mol％LiCl,25.0mol％PrCl_3);E(404℃,20.0mol％NaCl,55.4mol％LiCl,24.6mol％PrCl_3)。二元和三元相图液相限的测量误差约为±5℃和±7℃。     

固相反应合成Sr_(1+x)Zr_4P_(6-2x)Si_(2x)O_(24)磷酸盐粉体

以SrCO_3、SiO_2、ZrO_2和(NH_4)H_2PO_4为实验原料,采用固相反应法制备出磷酸盐Sr_(1+x)Zr_4P_(6-2x)Si_(2x)O_(24)(x=0～0.4)粉体.XRD和SEM分析表明:在1100 ℃,4 h温度下煅烧能够合成单相Sr_(1+x)Zr_4P_(6-2x)Si_(2x)O_(24)(x=0～0.4)粉体,1100 ℃,4 h条件下制备的Sr_(1+x)Zr_4P_(6-2x)Si_(2x)O_(24)(x=0～0.4)粉体成球状,平均粒径在300～500 nm之间.在1100 ℃煅烧温度下适当延长保温时间,有利于Sr_(1+x)Zr_4P_(6-2x)Si_(2x)O_(24)(x=0～0.4)单相粉体的形成.     

Phase diagram of the CuGaSe2–SiSe2 and CuInSe2–SiSe2 systems

The phase diagrams of the CuGaSe₂–SiSe₂ and CuInSe₂–SiSe₂ systems were constructed using the results of differential thermal and X-ray phase analysis. Both systems are of the eutectic type with the eutectic point coordinates 75 mol% SiSe₂, 1042 K (CuGaSe₂–SiSe₂); 67 mol% SiSe₂, 1083 K (CuInSe₂–SiSe₂). Solid solutions based on CuGaSe₂ and CuInSe₂ were discovered in these systems; their extent at 670 K being 24 and 25 mol% SiSe₂, respectively. The crystal structure of the limiting compositions of these solid solutions was refined.     

LIQUIDUS OF SYSTEM Ag-Cu-Ge

The diagram of Ag-Cu-Ge system was constructed from the investigation of 13 internal sec-tions by DTA heating as well as cooling curves in an atomsphere of dry N_2 . The phase dia-gram is subdivided into two pseudo-ternary systems shown as Ag-Cu-Cu_3Ge andAg-Cu_3Ge-Ge. Both systems belong to simple eutectic type. The ternary eutectic points liein." E_1, Ag(22.0)-Cu(58.8)-Ge(19.2), 632℃ and E_2 , Ag(44.3)-Cu(29.5)-Ge(26.2), 533℃.The three side binary systems were redetermined.     

原位合成方镁石-铁铝尖晶石材料

通过对铁铝尖晶石合成过程反应机理及MgO-Al_2O_3-FeOn三元体系中可能发生的高温反应进行热力学分析,尝试采用原位合成法制备方镁石-铁铝尖晶石材料,并用XRD、SEM等测试方法对材料进行了表征.结果表明:控制气氛10(-27117.9/T+11.54)＜Po_2＜10(-32625/T+18.09),经过1400, 1550 ℃高温处理后,能够成功合成出方镁石-铁铝尖晶石材料;同一温度下铁铝尖晶石的生成量随着金属铁加入量的增大而逐渐增多,1550 ℃处理后的试样FeAl_2O_4晶体发育更加良好.     

一种用于SOFC的有前途电解质:Sc~(3+)和Bi~(3+)共掺氧化锆(英文)

采用pechini方法合成了Sc、Bi共掺的氧化锆粉体,并且在1050～1500 ℃下进行烧结.通过XRD、拉曼光谱和交流阻抗等测试研究了物相组成和电导率.研究发现,Bi_2O_3的加入在降温过程,部分抑制了t'→t的相变,而且作为助烧剂提高了样品密度.当烧结温度为1400 ℃时,样品电导率最高 (大约10~(-2) S/cm, 500 ℃),这可能是由于在此温度下m相的消失和亚稳相t'的抑制分解所致.     

Electrochemical performances of LiFePO4/C composites prepared by molten salt method

LiFePO4/C composites were synthesized by a molten salt (MS) method using the mixture of LiCl,LiOH and NaCl.The prepared LiFePO4/C composites are characterized by X-ray diffractometry (XRD),field emission scanning electron microscopy (FESEM) and charge-discharge test.XRD patterns indicate that LiFePO4 prepared in the temperature range of 550-700 ℃ crystallizes well in an olivine-type structure.Through FESEM images,the sphere-like and homogeneous particles of 0.2 μm can be observed.The charge-discharge test shows that the materials prepared at 600 ℃ for 12 h have good electrochemical performance.At the rates of 0.2C (34 mA/g) and 0.5C,the discharge capacities are 144.6 and 122.3 mA·h/g,respectively,together with good cycle performances.     

Direct synthesis of Nb–Al intermetallic nanoparticles by sodiothermic homogeneous reduction in molten salts

Nb–Al intermetallic nanoparticles were directly synthesized via sodiothermic reduction process in molten salts using NbCl₅ and AlCl₃ as the raw materials. The as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The NbCl₅ and AlCl₃ were dissolved in LiCl–KCl–CaCl₂ or LiCl–KCl–NaCl–CaCl₂ molten salts forming a homogeneous system. It was found that a series of intermetallic nanoparticles, such as Nb₃Al, Nb₂Al, NbAl₃ and Nb₂Al/NbAl₃, were successfully synthesized at low temperature of 350–500 °C using the homogeneous molten salt systems. The phase transformations of Nb₃Al, Nb₂Al and NbAl₃, were achieved via the controllable variation of molar ratio of Nb to Al. Furthermore, the influence of the reaction temperature on the particle size of the intermetallic nanoparticles was also investigated.     

AZ91D熔体中原位合成TiC颗粒及冲刷腐蚀性能

利用原位合成反应法,在不同温度(740、760和780℃)下对AZ91D镁合金熔体保温40min,制备了TiC/AZ91D镁基复合材料。借助光学显微镜和X射线衍射仪,对TiC/AZ91D镁基复合材料的组织形貌和物相进行观察和分析,并对制备的复合材料在质量分数为3.5%的NaCl溶液+石英砂条件下进行冲刷腐蚀磨损试验。结果表明,在740℃保温40min制备的复合材料主要由α-Mg、β-Mg17Al12和Al3Ti组成。保温温度分别为760℃和780℃时,AZ91D镁合金中均出现了原位合成的TiC颗粒,并且随温度升高,TiC的数量增加。此外,TiC/AZ91D镁基复合材料在3.5%的NaCl溶液+石英砂中的冲刷腐蚀磨损性能随保温温度的升高而增加。经780℃保温40min后的复合材料呈出最好的耐冲刷腐蚀磨损性能,相比于AZ91D镁合金提高了60.5%。     

LIQUIDUS OF TERNARY SYSTEM LaCl_3-MgCl_2-LiCl

Two surfaces correponding to LaCl_3 and α-solid solution(MgCl_2.LiCl) respectively:and one secondary crystallization curve with a minimum M at 63.8 wt-％ LaCl_3,2.0 wt-％MgCl_2,34.2 wt-％ LiCl and 492℃ were fonud by means of DTA.In combination withliquidus determination.an approach was also made to the alteration in LnCl_3-MgCl_2-LiClsvstem,where Lu denotes La.Ce.Pr or Nd.     

AgNO<Subscript>3</Subscript>-LiNO<Subscript>3</Subscript>-RbNO<Subscript>3</Subscript> phase diagram

The ternary system of silver, lithium, and rubidium nitrates has been studied. Five vertical sections were established: AgNO₃-Li_0.5Rb_0.5NO₃; Li_0.5Rb_0.5NO₃-Ag_0.5Rb_0.5NO₃; 20 mol% AgNO₃; 80 mol% AgNO₃; and the section 5 mol% LiNO₃. Ten invariant points were found. A schematic representation of ternary equilibria is given. The three binary systems are also reported.     

Effect of salt-assisted reduction method on morphologies and size of metallic tungsten particles

A simple method was proposed to produce tungsten (W) particles with controllable shape and size by employing the salt-assisted hydrogen reduction. W particles with controlled shape and size were prepared by adjusting the amount of chlorine salts and the temperature. After adding salt additives, the dispersibility of final particles was obviously improved and more adequate growth of particles was obtained. It was found that the effect of NaCl and LiCl is particularly significant. The average sizes of the obtained W particles at 1038 K after adding 0.1 wt.% NaCl and 0.1 wt.% LiCl were 0.924 and 1.128 μm, respectively. With the increase of temperature and amount of chlorine salts, the dispersity of the produced W particles became much better, the size of W sub-particles was increased, and the shape of W sub-particles was changed from spherical to polyhedral. At 1349 K, the addition of chlorine salts even multiplied the particle size, and the average sizes of W particles with 1 wt.% NaCl and 1 wt.% LiCl were raised up to 21.367 and 29.665 μm, respectively. Based on the conventional pseudomorphic transformation and chemical vapor transport mechanisms, the effects of adding salts on the reaction mechanism were investigated in detail as well.     

RuO_2-SiO_2粉末的制备及其组织结构表征

采用正硅酸乙酯的sol-gel法和RuCl3的Pechini法结合,制备了70mol%RuO2-30mol%SiO2二元氧化物粉末。采用红外光谱(FT-IR)、综合热分析、X射线衍射(XRD)、TEM和比表面(BET)等测试技术研究了产物的形成过程和组织结构。结果表明,晶体颗粒尺寸约为10nm。在200～600℃范围内,SiO2都保持非晶结构。200℃、400℃烧结的样品中晶体只有单质Ru。600℃时,90vol%的Ru被氧化为颗粒大小与Ru单质相当的RuO2。400℃烧结的样品比表面积最大,孔径最小。非晶SiO2可以有效阻止颗粒尺寸长大。这对于钛阳极涂层的制备非常有利。     

电解液浓度对AT61、AP65镁合金阳极电化学性能的影响

采用X射线衍射仪、扫描电镜、能谱测试仪、电化学测试仪和电池测试仪等检测技术,分析了轧制退火态AT61(Mg-6%Al-1%Sn)和AP65(Mg-6%Al-5%Pb)镁合金阳极的成分,研究了质量分数分别为3.5%和7.0%NaCl电解液对这两种镁合金阳极电化学性能的影响。结果表明:经430 ℃×16 h均匀化热处理后,轧制退火态AT61和AP65镁合金中Mg₁₇Al₁₂相扩散于基体中;相对3.5%NaCl电解液,两种镁合金阳极在7.0%NaCl电解液中放电性能得到很大提升,同时镁合金-空气电池的放电稳定性得到增强。