Catalytic Activity of Nickel Alloys in Anodic Oxidation of the Hypophosphite Ion as a Function of Their Composition

The rate of anodic oxidation of the hypophosphite ion on alloys Ni-P, Ni-B, and Ni-Mo-P is studied as a function of their composition and structure. The organic compounds that are customarily used to stabilize electrolytes of electroless nickel plating are shown to come useful when controlling composition of the Ni-P coatings at the expense of their different influence on the rates of partial processes of deposition of the alloy components. The formation of catalytic activity of such coatings is affected mostly by a structural factor. With alloys Ni-P, Ni-B, and Ni-Mo-P, whose composition was varied by altering the concentration of the source of the alloying component, dependence of catalytic activity of the surface on the composition is defined mainly by an electronic factor.__________Translated from Elektrokhimiya, Vol. 41, No. 8, 2005, pp. 972–980.Original Russian Text Copyright © 2005 by Sotskaya, Dolgikh, Ryabinina.     

Eu,Dy共掺杂SrAl2O4长余辉材料制备新工艺

活化Al-Sr合金粉末水解制备SrAl₂O₄长余辉材料的前驱体,并采用高温固相反应法制备出Eu,Dy共掺杂的SrAl₂O₄长余辉材料,对其微观结构和发光特性进行了研究。实验结果表明:前驱体中Al、Sr元素在微观状态下分布均匀,所制成的长余辉发光材料的发射主峰位于520nm附近,为典型的Eu²⁺离子4f5d-4f的特征发射,初始亮度达到18cd/m²,余辉时间长达46h。     

复杂机械系统实用故障诊断原则的研究

在总结现有诊断技术成功应用实例的基础上,提出了一种新的实用诊断原则-“最少试验故障模”原则,对于复杂的机械设备和系统,采用这种新的研究思路有利于降低研究难度,提高研究成果的实用性.还以滑动轴承为例,通过对滑动轴承主要失效形式和机理的分析,说明可将滑动轴承简化为-多输入（多种故障原因）-单输出（接触摩擦）的灰色系统模型,并以滑动轴承各种故障的共同特征-接触摩擦作为滑动轴承故障诊断研究的唯一故障基准模.根据上述研究思路,对静、动载荷工作条件下滑动轴承的故障诊断进行了大量的实验研究.实践表明,提出的诊断原则诊断效率高,实用性强,可借鉴用于许多领域的故障诊断.     

铂钼合金零件冲裁模的制作分析及改进

以具体零件为例分析了铂钼合金采用复合模加工时的缺点，提出了具体的改进方案，并论述了改进后的级进模结构、工作过程及其优点。     

大型径向和推力滑动轴承试验台结构设计与应用

对径向滑动轴承、推力滑动轴承试验台以及实验台的结构设计、试验范围、功能和工业产品实验进行了介绍。该试验台在滑动轴承的实验研究中得到了很好的应用。     

Exact thermodynamic behavior of a generalized spin-isospin ising system on the Bethe lattice

We study a generalized Ising system consisting of a Bethe lattice on every site of which two spin-1/2 and two isospin-1/2 (or atomic species A) states can be realized, the spin-species interacting with appropriate nearest neighbor couplings. The system is equivalent to that of four states per site and we obtain its exact thermodynamic behavior. The case of a fixed concentration of species is the annealed or liquid magnetic binary alloy. The temperature dependence of the short-range-order (SRO) parameter of such systems is obtained as an application of the theory and discussed in connection with relevant material from the literature. When fixing both the concentration and the nearest neighbor spatial correlation of the species, we obtain Eggarter's formulas for the frozen-in species problem, which therefore are only approximately valid even on the Bethe lattice.     

液体和非晶态Ni64B36合金结构的从头算分子动力学模拟

运用从头算分子动力学模拟了液体以及猝冷后形成的非晶态Ni₆₄B₃₆合金体系, 得到了它们的对相关函数、结构因子、键对分析方面的结构信息, 与实验结果相当一致; 结果表明, 猝冷得到的合金性质与液体合金性质相似, 为非晶态结构. B原子多数以B—B双原子成键形式分散于Ni原子构成的骨架中. 电子态密度分析表明, Ni 3d电子最活泼, 因此在合金中Ni为活性位. 轨道电荷分析从电子结构角度揭示了在NiB 催化剂中B作为修饰剂的机理.     

金属铝燃料电池的研究

铝是一种丰富廉价的有色金属，金属铝电池作为一种新型燃料电池，具有低成本、无毒害、高功率、高能量密度等优点。本文简述了金属铝电池的工作原理，并对铝阳极、空气阴极、催化剂、电解液和铝燃料电池的应用等方面的研究概况进行了叙述。     

方波伏安法测定镍铜合金中的镍含量

在0.01mol·L-1的氨水-氯化铵缓冲溶液(pH 9.3)中,镍(Ⅱ)于-1.25V(vs.SCE)出现一灵敏的方波伏安峰。镍(Ⅱ)浓度在1.5×10-6～1.0×10-4mol·L-1与伏安峰高呈线性关系,线性方程为ip(μA)=2.1870+0.6328c(μmol·L-1),相关系数为0.9991。方法的标准偏差为0.7％。该法应用于镍铜合金样品中镍的测定,结果满意。