经编二元网在双加压法硝酸装置的应用

通过对双加压法硝酸装置铂网使用情况和铂网脱边事故的统计，分析了氧化炉采用平编三元网存在的问题；论述了经编二元网的特性和优点；计算了铂网的生产强度和接触时间，确定了铂网丝径；总结了硝酸装置使用经编二元网的运行效果和经济效益，结果表明，吨酸氨耗降低了2．48kg，铂耗降低了10mg，经编二元网优于平编三元网。     

基于LS-SVM逆系统的无轴承异步电机解耦控制

无轴承异步电机具有非线性、多变量和强耦合的特点,要实现电机稳定悬浮和旋转运行,必须对其进行非线性动态解耦控制。为了克服逆系统方法精确建模难的局限性,采用基于最小二乘支持向量机(LS-SVM)α阶逆系统方法对无轴承异步电机进行动态解耦控制的研究。首先利用最小二乘支持向量机辨识出无轴承异步电机的逆模型,然后将它串联在原系统前,将无轴承异步电机解耦成四个独立的伪线性子系统-2个径向位移子系统、一个速度子系统和一个磁链子系统。为保证鲁棒性能,最后对解耦后的系统采用非线性内模控制策略。研究表明,LS-SVMα阶逆系统方法能够实现无轴承异步电机径向悬浮力和旋转力之间的动态解耦控制,控制系统具有良好的静态和动态性能。     

扩展双星树的 Wiener-E 指标和 Wiener-O 指标

扩展双星树（T（n）n1,n2）是 n－1长路径的两端点分别联结 n1条悬挂边和 n2条悬挂边所得到的图。论文根据扩展双星树的结构特征,研究了扩展双星树的类Wiener指数,给出了一般计算公式。     

双水解法制备SO4^2-/SnO2·SiO2固体超强酸及其结构表征

用双水解法合成了SO24-/SnO2-SiO2固体超强酸催化剂。采用FTIR、TG-DTA和XRD技术研究了SO24-/SnO2-SiO2的结构,其测试结果表明:SO42-/SnO2-SiO2的结构与其催化活性存在很好的一致性。     

一步法制二甲醚工艺及催化剂的研究

本文采用共沉淀沉积法制备了一步法合成二甲醚的双功能催化剂，并在固定床高压流动反应装置上对其催化性能进行研究，考察了MnO2助剂对Cu—ZnO—ZrO2／HZSM—5催化剂性能的影响以及工艺条件对二甲醚合成的影响。采用TPR、XRD等测试方法对催化剂进行了表征，结果证明：MnO2助剂的加入，能够增加活性中心数量，提高催化剂的活性。     

Chemical analysis of volatiles emitted by Pinus svlvestris after induction by insect oviposition

Gas chromatography – mass spectrometry analyses of the headspace volatiles of Scots pine (Pinus sylvestris) induced by egg deposition of the sawfly Diprion pini were conducted. The odor blend of systemically oviposition-induced pine twigs, attractive for the eulophid egg parasitoid Chrysonotomyia ruforum, was compared to volatiles released by damaged pine twigs (control) that are not attractive for the parasitoid. The mechanical damage inflicted to the control twigs mimicked the damage by a sawfly female prior to egg deposition. The odor blend released by oviposition-induced pine twigs consisted of numerous mono- and sesquiterpenes, which all were also present in the headspace of the artificially damaged control twigs. A quantitative comparison of the volatiles from oviposition-induced twigs and controls revealed that only the amounts of (E)--farnesene were significantly higher in the volatile blend of the oviposition-induced twigs. Volatiles from pine twigs treated with jasmonic acid (JA) also attract the egg parasitoid. No qualitative differences were detected when comparing the composition of the headspace of JA-treated pine twigs with the volatile blend of untreated control twigs. JA-treated pine twigs released significantly higher amounts of (E)--farnesene. However, the JA treatment induced a significant increase of the amount of further terpenoid components. The release of terpenoids by pine after wounding, egg deposition, and JA treatment is discussed with special respect to (E)--farnesene.     

B位掺杂钙钛矿结构化合物LaSr2Mn2-xFexO7的电磁性能

研究了以Fe离子(Fe3 )掺杂取代部分锰(Mn)离子的层状钙钛矿结构化合物LaSr2Mn2-xFexO7(O≤x≤O.3)的电性和磁性.结果发现:Fe3 的掺杂抑制了LaSr2Mn2-xFexO7低温的反铁磁性交换作用,使Neel温度TN由x=0的138K降至x=0.3的l0lK.同时,LaSr2Mn2-xFex07的自旋玻璃态、电荷有序和金属一绝缘体转变温度都由于Fe3 取代Mn离子而受到抑制.产生上述现象的原因是因为Mn位被取代导致产生无序状态.由于Fe3 取代Mn粒子,致使双交换作用通道被打破,化合物的电阻率随x的增加而迅速增加.所有化合物的电阻率在低温阶段都可以用Mott的变程跳跃理论来拟合;在高温阶段可以用最近小声子极化理论来拟合.     

Suppression of the α → β-nickel hydroxide transformation in concentrated alkali: Role of dissolved cations

The presence of dissolved cations such as Al and Zn in alkaline electrolyte (6 M KOH) suppresses the -nickel hydroxide transformation. The uptake of Al (10 mol%) and Zn (30 mol%) exhibited by the active material likely stabilizes the -phase. Dissolved Al is deleterious to the performance of the nickel hydroxide electrode, whereas, dissolved Zn enhances the specific discharge capacity of nickel hydroxide by approximately 25% showing that the mode of metal uptake is different in the two cases.     

A novel shaft-less double suction mini pump

A novel double suction shaft-less mini pump was developed for heat control of small energy systems in this study.The mini pump impeller with an exit diameter of 40 mm was combined with the motor rotor supported by the hybrid dynamic bearing.The specific speed of the pump was 125 min-1 m3 min-1 m.The hydraulic performance of the pump was investigated experimen-tally under four rotational speeds.From the test results,it was recognized that the pump could provide a flow discharge of 5 L/min and head of 1.5 m,w...     

Dynamic equivalent method of interconnected power systems with consideration of motor loads

The existing equivalent methods usually only deal with static load models and neglect the dynamic characteristics of loads such as induction motors.This paper presents a dynamic equivalent method which considers motor dynamics.At first,the clustering criterion of motor loads is given.The motors with similar dynamic characteristics are classified into one group.Then,reduction of motors in the same group is carried out.Finally,parameters of the equivalent motor are calculated and the equivalent system is thus...