Zn1—yAlyO敏感材料的固溶及导电机制

用化学共沉淀法，经热处理制得Ｚｎ１－ｙＡｌｙＯ系敏感材料。实验发现，在ｙ〈０．０８区间内，材料的电阻降低幅度较大，当ｙ〉０．０８时，阻值开始随ｙ值增大而上升。ＸＲＤ分析表明Ｚｎ１－ｙＡｌｙＯ是固溶体，此体系中存在Ａｌ＾ｘＺｎ→ＡｌＺｎ＿ｅ缺陷平衡，并探讨其导电机制。     

超负磁致伸缩晶体Sm－Fe、Sm－Dy－Fe和Sm－Dy－Fe－Al的研究

本文研究了轻稀土负磁致伸缩ＳｍＦｅ＿ｘ（１．４０＜ｘ＜１．９４），Ｓｍ＿ｘＤｙ＿（１－ｘ）Ｆｅ＿ｙ（０．８４＜ｘ＜０．９２．１．８０＜ｙ＜１．９０），Ｓｍ＿（０．９０）Ｄｙ＿（０．１０）（Ｆｅ＿（０．９５）Ａｌ＿（０．０５））＿（１．８０）晶体的制备、热处理及磁学性能，发现ＳｍＦｅ＿ｘ合金的λ－ｘ曲线存在两个峰值，峰值的ｘ点随热处理发生的变化有一定的规律性，还比较了热处理前后，Ｓｍ－Ｆｅ、Ｓｍ－Ｄｙ－Ｆｅ和Ｓｍ－Ｄｙ－Ｆｅ－Ａｌ的相组成对性能的影响。热处理用于改善磁致伸缩性能，并且制得了高磁致伸缩性能的ＳｍＦｅ＿２和（Ｓｍ，Ｄｙ）Ｆｅ＿２合金。     

立方A^4＋M^5＋2O7型化合物与新型负热膨胀材料

概述了立方Ａ＾４＋Ｍ＾５＋２Ｏ７型化合物的结构特点，讨论了ＡＶ２－ｘＰｘＯ７型（Ａ＝Ｚｒ或Ｈｆ；ｘ＝０．１～１．２）及其部分取代的Ａ＾４＋１－ｙＢ＾４＋ｙＶ２－ｘＰｘＯ７型（Ｂ＝Ｔｉ，Ｃｅ，Ｔｈ，Ｕ，Ｍｏ，Ｐｔ，Ｐｂ，Ｓｎ，Ｇｅ或Ｓｉ；ｙ＝０．１～０．４）和Ａ＾４＋１－ｙＣ＾１＋ｙＤ＾３＋ｙＶ２－ｘＰｘＯ７型（Ｃ为碱金属元素，Ｄ为稀土金属元素）材料的负热膨胀性能。     

氚固体增殖剂偏铝酸锂多孔陶瓷研究

采用喷雾干燥－热分解法制得了平均粒径０．１μｍ的γ－ＬｉＡｌＯ２超细粉，该粉末经冷压烧结成型工艺制得密度８０％（Ｔ．Ｄ）、孔径分布为０．０８～０．４μｍ的γ－ＬｉＡｌＯ２多孔陶瓷芯块，已成功地用于我国第一条产氚演示回路上。     

Li1+2x+yAlxNdyTi2-x-ySixP3-xO12系统的锂快离子导体研究

Ｌｉ１＋２ｘ＋ｙＡｌｘＮｄｙＴｉ２－ｘ－ｙＳｉｘＰ３－ｘＯ１２锂快离子导体可以用精选的天然高岭石Ａｌ４「Ｓｉ４Ｏ１０」（ＯＨ）８为起始原料，经与Ｌｉ２Ｃｏ３、ＴｉＯ２、ＮＨ４Ｈ２ＰＯ４进行高温（８００－１０００℃固相反应约２０ｈ而制得，一个空间群属于Ｒ３Ｃ的固溶体导电相可在ｙ＝０．５，ｘ≤０．３和ｙ＝１．０，ｘ≤０．４的组成范围内发现，该盯具有较好的电导性较低的活化能，起始组成ｙ＝１．０，ｘ＝０．     

La_（1－x）SrxCoO_（3－y）导电陶瓷制备工艺的研究

用固相反应法制备了Ｌａ＿（１－ｘ）Ｓｒ＿ｘＣｏＯ＿（３－ｙ）导电陶瓷材料，研究了制备工艺对烧结性能的影响。实验结果表明：烧结体的致密度取决于预烧温度、烧成温度及保温时间，此外还与成型方法等因素有关。在１０００～１３００℃保温２～１５ｈ获得了高密度、导电性良好的立方钙钛矿型Ｌａ＿（１－ｘ）Ｓｒ＿ｘＣｏＯ＿（３－ｙ）（ｘ＝０．５，０．６）陶瓷材料。用Ｘ射线分析了材料的相组成和结构。     

超负磁致伸缩晶体Sm—Fe,Sm—Dy—Fe和Sm—Dy—Fe—Al的研究

本文研究了轻稀土负磁致伸缩ＳｍＦｅｘ（１．４０≤ｘ≤１．９４），ＳｍｘＤｙ１－ｘＦｅｙ（０．８４≤ｘ≤０．９２，１．８０≤ｙ≤１．９０），Ｓｍ０．９０Ｄｙ０．１０（Ｆｅ０．９５Ａｌ０．０５）１．８０晶体的制备，热处理及磁学性能，发现ＳｍＦｅｘ合金的λ－ｘ曲线存在两个峰值，峰值的ｘ点热处理发生的变化有一定的规律性，还比较了热处理前后，Ｓｍ－Ｆｅ、Ｓｍ－Ｄｙ－Ｆｅ和Ｓｍ－Ｄｙ－Ｆｅ－Ａｌ的相组成对性能     

K_2NbOF_5－MF_3系玻璃的结构及电性质

研制了Ｋ＿２ＮｂＯＦ＿５－ＭＦ＿３（Ｍ＝Ａｌ、Ｇａ）新体系氟化物玻璃，测定了玻璃的特征温度、Ｒａｍａｎ光谱和电导率，玻璃中Ｎｂ￣（５＋）、Ａｌ￣（３＋）、Ｇａ￣（５＋）分别以ＮｂＯＦ、ＡＩＦ、ＧａＦ八面体形式存在，玻璃的电导率随ＡｌＦ＿３含量的增加而增加，ＡｌＦ＿３含量达到３０ｍｏｌ％时，Ａｌ￣（３＋）除ＡＩＦ八面体外，还有ＡｌＦ四面体结构出现，同时电导率降低，Ｆ￣－阴离子是主要的导电离子，７５Ｋ＿２ＮｂＯＦ＿５·２５ＡｌＦ＿３玻璃的电导率在１９６℃时，σ＝１．０２×１０￣（－２）Ｓ·ｃｍ￣（－１）。     

Al_2O_3－MgAl_2O_4陶瓷的试验研究

在Ａｌ＿２Ｏ＿３中添加５－１５ｗｔ％ＭｇＡｌ＿２Ｏ＿４，采用热压注法制备Ａｌ＿２Ｏ＿３－ＭｇＡｌ＿２Ｏ４陶瓷。研究表明，Ａｌ＿２Ｏ＿３－ＭｇＡｌ＿２Ｏ＿４陶瓷具有良好的高温电阻率和抗熔渣－种子的腐蚀能力，经过进一步改进可望作为燃煤ＭＨＤ发电通道（半热壁型）阳极区电极间绝缘片材料。     

氚固体增殖剂偏铝铝酸锂多孔陶瓷研究

采用喷雾干燥－热分解法制得了平均粒径０．１μｍ的γ－ＬｉＡｌＯ２超细粉，该粉末经冷压烧结成型工艺制得密度，孔径分布为０．０８－０．４μｍ的γ－ＬｉＡｌＯ２多孔陶瓷芯块，已成功地用于我国第一条产氚演示回路上。     

（Ti—Nb1—y）Cx固溶体的机械合金化合成

研究了不同组成的ＴｉＣ－Ｎｂ粉用机械合金化合成的固溶体（ＴｉｙＮｂ１－ｙ）Ｃｘ，并与电弧熔炼的（ＴｉｙＮｂ１－ｙ）Ｃｘ固溶体比较，结果表明，二者的ＸＲＤ谱及晶格常数变化完全一致。     

（Ti_yNb_（1－y））C_x固溶体的机械合金化合成

研究了不同组成的ＴｉＣ—Ｎｂ粉用机械合金化合成的固溶体（ＴｉｙＮｂ（１－ｙ））Ｃｘ，并与电弧熔炼的（ＴｉｙＮｂ（１－ｙ））Ｃｘ固溶体比较，结果表明，二者的ＸＲＤ谱及晶格常数变化完全一致     

M - C dipole formation in fcc (face centred cubic) Fe1-yMyCx solid solution (M=Ti,Nb)

Abstract

Available equilibrium carbon solubility data for fcc (face centred cubic) Fe_{1 - y}M_yC_x solid solution (M = Ti,Nb) reported as functions of temperature T and carbon activity a (C) were analysed taking into account the atomic interaction parameters derived through statistical thermodynamic analysis of related systems. In the fcc Fe_1-yM_yC_x under consideration, the affinity between C atom and M atom (M = Ti,Nb) is very much more attractive than that between C and Fe. Correspondingly, the atom configuration model in which M atoms are distributed randomly over the metal sub-lattice Fe_{1 - y}M_y and all the M atoms in the Fe_{1 - y}M_yC_x are bonded to C to form M - C dipoles was concluded to be the most realistic one reproducing the experimentally determined a (C) - T - x relationships at respective y.     

Self-assembling of zinc and tellurium impurities in zinc-blende MgS

Conditions providing a thermodynamic advantage governing the self-assembly of Zn and Te impurities in metastable magnesium sulfide (MgS) with zinc-blende structure have been theoretically studied. The formation of tetrahedral 1Te4Zn cells is thermodynamically favorable in Zn_xMg_{1 ? x} Te_yS_{1 ? y} (x ≥ 4y) solid solutions enriched in MgS in the region of dilute Te concentrations. At temperatures selected for the growth (230°C) and annealing (500°C), the free energy of a solid solution in which separate Te atoms must be surrounded only by Zn atoms is lower than that of the solution with a random arrangement of these impurities. This phenomenon is due to a thermodynamic advantage of the formation of Mg-S and Zn-Te bonds over Zn-S and Mg-Te bonding, as well as due to a decrease in the elastic strain energy upon self-assembly of the given isoelectronic impurities.     

Indium and gallium oxynitrides prepared in the presence of Zn by ammonolysis of the oxide precursors obtained via the citrate route

Ammonia nitridation of indium and gallium oxide precursors obtained through a soft solution route led to their oxynitrides [In_0.97□_0.03][N_0.92O_0.08] at 660 °C and [Ga_0.89□_0.11][N_0.66O_0.34] at 850 °C, respectively, where □ refers to a In or Ga vacancy. Cation vacancies in their wurtzite-type lattice were eliminated in similar preparations with the co-presence of Zn²⁺ by forming complete solid solutions of (InN)_1−x(ZnO)_x and (GaN)_1−y(ZnO)_y. The optical absorption edge shape was found to be relatively steep at the solid solution limits of x ≈ 0.23 and y ≈ 0.33 compared to the case without zinc.     

Partial phase diagram of new quarternary semiconductor Pb1-x Mn x S1-y Se y for mid-infrared lasers

The phase diagram of the PbS-PbSe-MnSe-MnS system was investigated with an emphasis on the lead-rich Pb_1-x Mn _x S_1-y Se _y solid solution by differential thermal analysis, X-ray powder diffraction method and X-ray micro analysis. TheT-x phase diagrams of the PbS-MnS and PbSe-MnSe systems are presented. The isothermal phase diagram of the PbS-PbSe-MnSe-MnS system are also presented for T 950°C. The solid solubility and lattice constant of the Pb_1-x Mn _x S_1-y Se _y solid solution were determined.     

利用Mg含量控制Zn_(1-x)Mg_xO薄膜压敏电阻器的阈值电压

利用溶胶-凝胶法制备了Zn1-xMgxO压敏薄膜,并通过X射线衍射、X射线能谱、紫外-可见光谱仪、I-V特性测试仪等对薄膜及其压敏特性进行了表征。XRD结果表明,掺Mg后Zn1-xMgxO薄膜仍然为六方纤锌矿ZnO晶体结构;紫外-可见吸收谱表明,随着薄膜中Mg含量的增加,薄膜的吸收边蓝移,禁带宽度增加。I-V特性曲线表明,基于Al/Zn1-xMgxO/Si结构的薄膜压敏电阻器的阈值电压随着Mg含量的增加而增加,因此可以通过调节Mg含量实现对Zn1-xMgxO薄膜压敏电阻器阈值电压的调节。上述现象表明,Zn1-xMgxO薄膜压敏电阻器的压敏阈值电压与禁带宽度有关,即与Zn1-xMgxO薄膜中电子的本征跃迁有关。     

Flux pinning in melt grown LRE123 superconductors

Unlike Y123 which forms only a stoichiometric compound, the light rare earth elements (LRE: La, Nd, Sm, Eu, Gd) form a solid solution LRE_1+xBa_2–xCu₃O_y. When LRE123 superconductors are melt-processed in a reduced oxygen atmosphere, they exhibit high T_c's and large J_c values in high magnetic fields associated with a second peak effect. We believe that such a behavior is closely related to the presence of a LRE-Ba solid solution. In this paper we propose the flux pinning mechanism of LRE 123, and then discuss the source of the peak effect.     

Thermodynamic analysis of equilibria in Fe-Cr-C alloys and evaluation of their dusting stability in aggressive carboniferous atmospheres

Thermodynamic analysis of phase transformations and reactions in Fe-Cr-C alloys is carried out with allowance made for all possible states, both stable and metastable, in the temperature range of metal dusting in aggressive carboniferous atmospheres. The results are compared with data on the corrosion resistance of chromium steel pipes under oil refining conditions. It is shown that, at high temperatures, one of the equilibrium phases in this system is the cementite solid solution (Fe_1-y Cr_y)₃C. Below 930 K, this phase becomes unstable to the decomposition into mixtures containing other carbides, but the tendency for chromium to stabilize cementite persists. The metal dusting mechanism changes in the composition range 0.03 y 0.055 (2.8–5.1 wt % Cr). This conclusion is supported by the results of tests on chromium steel (15Kh5M and 15Kh2M1) pipes under oil refining conditions, which indicate that the introduction of chromium into Fe alloys can only inhibit the degradation of Fe-Cr-C alloys under metal dusting conditions, without fully preventing it.Translated from Neorganicheskie Materialy, Vol. 41, No. 2, 2005, pp. 177–184.Original Russian Text Copyright © 2005 by Alshevskii, Baklanova, Zaitsev, Maltsev, Rodionova, Rybkin, Shaposhnikov.     

Equilibrium relationships in the system NiO-CoO-O2

As part of a programme to investigate the possibility of using conducting oxide electrodes in the fused carbonate fuel cell, equilibrium relationships in the system NiO-CoO-O₂ were investigated using a thermobalance. An isobaric ternary diagram of the system was constructed and it is shown that the variation in the temperature of the boundary between the single phase (NiO-CoO solid solution) and the two phase (Co₃O₄ + NiO-CoO solid solution) fields, with cationic composition, is consistent with approximately ideal behaviour. A mechanism based on the established phase relationships is also suggested to explain the observation that loss of oxygen from two-phase mixtures on heating results in the formation of NiO-CoO solid solution in the interior of the Co₃O₄ grains. Results are also presented to show the effects of composition and heat-treatment on the electrical conductivities at high temperatures of selected mixtures.