复Banach空间单位球上几类映射的增长掩盖定理

对α次的殆β型螺形映射,α次的β型螺形映射和α次的强β型螺形映射,给出了定义,并且在复Banach空间中的单位球上分别得到它们的增长掩盖定理．     

Synthesis and Structural Characterization of Manganese Carbonyl Incorporated Polyoxomolybdate (n-Bu_4N)_2[Mo_6O_(16)(OCH_3)_2{HOCH_2C(CH_2O)_3}_2{Mn(CO)_3}_2]

The polyoxoanion incorporated {Mn(CO)3+} complex, (n-Bu4N)2[Mo6O16(OCH3)2{HOCH2C(CH2O)3}2· {Mn(CO)3}2](1), has been synthesized by the reaction of (n-Bu4N)4[Mo8O26] with Mn(CO)5Br in methanol, in the presence of C(CH2OH)4. The complex 1 has been characterized by IR, UV-Vis, X-ray single crystal diffraction, and TG. Crystal data for the complex 1: C25H48MnMo3NO16 (1), Triclinic P1, a=0.9405(3) nm, b=1.3351(4) nm, c=1.5455(4) nm, α=103.206(5)o, β=102.165(5)o, γ=100.784(5)o, V=1.7896(9) nm3, Z=2, R1=0.0703, wR...     

钛合金表面MAO/粘接PTFE涂层的真空摩擦学性能

采用真空球盘摩擦试验机,分别在低载、中载和重载工况下测试了一种MAO/粘接PTFE复合涂层的摩擦学性能.结果表明:微弧氧化层提升了基底抵抗变形的能力,确保了摩擦过程中粘接PTFE涂层与基底结合状态的稳定,并且在原位生长过程中继承了金属表面原有的机械加工形貌,形成了特殊的"波峰"与"波谷"交替并存的"波状"多孔地形."波峰"与孔壁作为与摩擦对偶接触的硬质区域起承载和耐磨损作用,"波谷"和微孔作为与摩擦对偶接触的软质区域起贮存润滑剂与提供转移膜的作用.在两者的耐磨-减摩协同作用下,MAO/粘接PTFE复合涂层在不同接触应力条件下的摩擦学寿命较传统的喷砂/粘接PTFE的摩擦学寿命有了极大提升.     

二维变几何域下的表面热流反演

采用共轭梯度法,给出二维变几何域下的热流反演算法,并对算法的有效性和稳定性进行验证.结果显示:测点数目对反演结果有较大影响,测点数目的选取和热流的空间变化剧烈程度有关;反演初值的选取对反演结果,尤其是末时段,会有较大影响,应尽可能选择传热过程末时刻热流作为反演初值.     

不同形貌纳米氧化锌的合成及其抗菌活性

采用微波超声波组合法合成了3个不同形貌的纳米氧化锌样品,对样品的组成及形貌进行了表征,并测定了所合成3个样品对金黄色葡萄球菌(S.aureus)的抑菌活性.结果表明,所合成的3个样品分别为高纯度的花状多级结构(样品1)、纺锤状结构(样品2)及均一的棱柱状结构(样品3)纳米氧化锌.在紫外光照射后样品均具有明显抗菌活性,3个样品的抑菌活性由大到小的顺序为:棱柱状,花状,纺锤状.其中,棱柱状纳米氧化锌在浓度为3g/L时的抑菌圈为15.3mm,在浓度为0.1g/L时的抑菌率可达89.74%.     

2-氰基苄基诱导的葡萄糖醛酸β糖苷键立体选择性

以2,3-O-(2-氰基苄基)-4-O-氯乙酰基-β-对甲基苯基-D-葡萄糖醛酸硫苷等7个单糖模块作为糖基供体, 以甲醇等醇类化合物作为糖基受体, 分别在二氯甲烷和甲苯溶剂中进行了糖基化反应, 研究了葡萄糖醛酸C2位引入2-氰基苄基(BCN)以及溶剂效应对糖苷键α/β选择性的影响. 通过对糖基产物的 ¹H NMR, ¹³C NMR和HSQC等谱图分析发现, BCN可以有效提高糖苷键的β选择性, 其中部分糖基化产物的糖苷键α/β比例最高可达1/50. 为磺达肝癸钠分子中葡萄糖醛酸的β糖苷键的构建方法做出了初步探索.     

Mahler型函数值的代数无关度量

利用初等的结式方法研究满足多项式形式的函数方程组的Mahler型函数的零点估计,给出了满足非线性函数方程组的Mahler型函数在代数点值的代效无关度量．     

Thermal design and simulation of space-borne membrane antenna

Thermal deformation of space-borne radar antenna caused by dramatic changes in orbit thermal environment has a serious effect on image qualities. In this paper, the NX TMG module was used to simulate the orbit thermal environment of the antenna, and a thermal control design was proposed. The thermal control structure consists of three layers; the top is a radiator with high emissivity surface, the middle is a multi-layer insulation, and the bottom is a highly reflective layer. The simulation results show that the thermal design could reduce the temperature gradient from 238.1 to 31.4 °C effectively.

     

A partial proximal point algorithm for nuclear norm regularized matrix least squares problems

We introduce a partial proximal point algorithm for solving nuclear norm regularized matrix least squares problems with equality and inequality constraints. The inner subproblems, reformulated as a system of semismooth equations, are solved by an inexact smoothing Newton method, which is proved to be quadratically convergent under a constraint non-degeneracy condition, together with the strong semi-smoothness property of the singular value thresholding operator. Numerical experiments on a variety of problems including those arising from low-rank approximations of transition matrices show that our algorithm is efficient and robust.