与时俱进培养高素质创新型人才

很高兴能有这样一个机会在这里和工科数学的同行们一起讨论数学改革的问题 .我想讲两方面问题 :1　当前社会发展的特点和对高等教育的要求我想在谈论教学改革之前先了解一下当前社会发展的特点和对高等教育的要求 ,可以使我们高屋建瓴 .第一个特点 ,是社会与发展通过农业经济社会、工业经济社会、进入了知识经济社会 .知识经济社会的特征是 :知识和能力已成为社会发展的主要资源和生产要素 ;知识的创新、传播和应用是经济和社会发展的核心 .这样一个特点 ,对高等教育提出两方面的要求 :一方面是要普及、提高各级劳动者的科学文化素质 ,使我…     

中国各地区现代化的因子分析及非均衡差异研究

本文依据构建的中国地区现代化指标体系对中国31个地区25个指标进行了因子分析及非均衡差异研究,得出了中国各地区现代化水平具有了非均衡性、整体偏低性和梯度演变性结论,从而提出了不同区域集团应采取有差别的现代化战略.     

Improving nucleation in the fabrication of high-quality 3D macro-porous copper film through the surface-modification of a polystyrene colloid-assembled template

A new approach is developed to the fabrication of high-quality three-dimensional macro-porous copper films. A highly-ordered macroporous copper film is successfully produced on a polystyrene sphere (PS) template that has been modified by sodium dodecyl sulfate (SDS). It is shown that this procedure can change a hydrophobic surface of PS template into a hydrophilic surface. The present study is devoted to the influence of the electrolyte solution transport on the nucleation process. It is demonstrated that the permeability of the electrolyte solution in the nanochannels of the PS template plays an important role in the chemical electrodeposition of high-quality macroporous copper film. The permeability is drastically enhanced in our experiment through the surface modification of the PS templates. The method could be used to homogeneously produce a large number of nucleations on a substrate, which is a key factor for the fabrication of the high-quality macroporous copper film.     

双层金属锥形扁壳的非线性热稳定性

本文提出有关双层金属锥形扁壳在均匀温度场作用下的非线性稳定性的一般理论.将双层壳体的基本方程简化为与经典壳体理论相似的形式,通过比拟,以作用于锥形扁壳边界上的均匀分布的相当边界力矩来替换温度效应,采用修正迭代法求解.文中给出了临界跳跃力矩曲线.它对于工程上各种仪表弹性元件的设计具有一定的参考价值.     

回旋加速器有多大？

本文用氢原子的Ｂｏｈｒ半径ａ０及精细结构常数ａ 计算实验回旋加速器中给定能量粒子的轨道半径     

涟波箱水面波的传播速度问题

本文分析和描述涟波箱水面波中各质点的运动规律,应用“大学物理”中的理想流体稳定流动中的伯努利原理,对涟波箱水波传播速度与波长和水深的关系予以讨论,以了解涟波箱水面波传播速度的变化规律,有助于进一步理解涟波箱演示器的原理.     

Insight into influence of thermodynamic coefficients on transient negative capacitance in Zr-doped HfO2 ferroelectric capacitors

We study the influence of the thermodynamic coefficients on transient negative capacitance for the Zr-doped HfO₂ (HZO) ferroelectric capacitors by the theoretical simulation based on the Landau-Khalatnikov (L-K) theory and experimental measurement of electrical properties in the resistor-ferroelectric capacitor (R-FEC) circuit. Our results show that the thermodynamic coefficients α, β and γ also play a key role for the transient NC effect besides the viscosity coefficient and series resistor. Moreover, the smaller coefficients α and β, the more significant the transient NC effect. In addition, we also find that the thermodynamic process of transient NC does not obey the generally accepted viewpoint of Gibbs free energy minimization.     

Synthesis of flower-like WS2 by chemical vapor deposition

Flower-like tungsten disulfide (WS₂) with a diameter of 5-10 μm is prepared by chemical vapor deposition (CVD). Scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), Raman spectroscopy, and ultraviolet-visible (UV-vis) spectroscopy are used to characterize its morphological and optical properties, and its growth mechanism is discussed. The key factors for the formation of flower-like WS₂ are determined. Firstly, the cooling process causes the generation of nucleation dislocations, and then the "leaf" growth of flower-like WS₂ is achieved by increasing the temperature.     

国产六面顶压机多晶种法合成宝石级金刚石单晶

对国产六面顶压机平台下使用多晶种法合成宝石级金刚石单晶进行了系统的研究. 通过合理调整温度梯度法的合成腔体组装, 采用多晶种法, 探索多晶种法金刚石合成的压力和温度区间, 在单个合成腔体内放置3–5颗金刚石晶种, 成功合成出多颗(3–5)优质Ib型宝石级金刚石单晶. 多颗晶种的引入, 单次实验合成的多个金刚石晶体晶形及品质一致; 同时, 晶体的整体生长速度也有明显的增大. 多晶种法金刚石单晶合成的研究, 可以有效地利用腔体空间、提高单次金刚石单晶合成的效率, 解决压机大型化下高温高压资源利用率低的问题; 同时, 为宝石级金刚石单晶商业化生产提供重要的依据. 关键词： 金刚石 国产六面顶 多晶种 温度梯度法