横向外延过生长磷化铟材料的生长速率模型

分别考虑气相扩散和掩膜表面扩散过程，建立了金属有机化学气相沉积条件下横向外延过生长的速率模型. 在砷化镓衬底上外延磷化铟条件下，模拟得到了生长速率随掩膜/窗口宽度(m/w)变化的关系. 通过讨论掩膜/窗口宽度的影响，说明了掩膜宽度、窗口宽度以及有效掩膜宽度是决定生长速率的关键因素. 以上结论与实验结果一致. 关键词： 横向外延 生长模型 扩散 生长速率     

如何引导学生主动参与物理教学活动

物理教学不是让学生被动的吸收知识、反复练习、强化记忆的过程，而是让学生以积极的心态，主动参与，运用已有的知识和经验，探究解决问题的方法，构建新的知识体系的过程那么，如何引导学生主动参与物理教学活动呢？     

Antitumor Metallothiosemicarbazonate： Synthesis,Crystal Structure,Spectra and Antitumor Studies of Co（Ⅲ） Complex with Thiosemicarbazone Derivative of 2-Benzoylpyridine

The title complex [Co（L）2]Cl·4H2O I has been achieved via self-assembly by incorporating cobalt into 2-benzoylpyridine thiosemicarbazonate ligand, and characterized by elemental analysis, infrared spectra, mass spectra and single-crystal X-ray diffraction study. The crystal crystallizes in monoclinic, space group P2 1/n, with a = 10.227（3）, b = 17.363（4）, c = 17.459（4） A, β= 100.408（4）°, V= 3049.2（13） A^3, Z = 4, Mr = 677.08, Dc = 1.475 g/cm^3, μ（MoKα） = 0.834 mm^-1, F（000） = 1400, the final R = 0.0747 and wR = 0.0896 for 1663 observed reflections with I 〉 2σ（I）. The complex contains one six-coordinated cobalt ion connected by two thiosemicarbazone ligands which act as a tridentate ligand to coordinate with the center metal atoms via two pyridyl nitrogen atoms, two imine nitrogen atoms and two sulfur atoms giving rise to a mononuclear structure. Hydrogen bonds existing in the complex link the different components to stabilize the crystal structure. The antiturnor activity of the title complex was tested against A549 lung cancer cell line. Complex ! exhibits antitumor activity.     

关于拉氏变换性质的应用条件

本本对拉氏变换的象函数的微分性质和延迟性质的应用条件作一些说明。     

Large Decay Rate Variation of ^7Be in Pd and Au

Platinum and gold have the similar crystal structure but different electronic affinities, as well as different effective electron densities near the implanted ions. Both the differences favour larger decay rate of ^7 Be in Pd than that in Au. We measured the variation of the decay rate of ^7Be implanted in Pd and Au host materials. We have found that the decay rate of ^7 Be in Pd is larger than that in Au by 0.8%.     

CaTiO3基微波介质陶瓷的频率温度稳定性

通过对克劳修斯-莫索蒂方程的近似, 分析了钙钛矿结构微波介质陶瓷频率温度系数 (τ_f) 的主要影响因素, 发现改变材料介电响应中离子位移极化和电子位移极化的比例, 可调节频率温度系数的正负与大小. 通过电子结构计算和容忍因子分析, 预测引入(Zn_1/3Nb_2/3)⁴⁺对具有正温度系数 的CaTiO₃进行B位取代将提高材料电子极化响应比例, 调节τ_f由正变负. 采用偏铌酸盐为前驱体, 通过固相反应法合成了Ca[(Zn_1/3Nb_2/3)_xTi_(1-x)]O₃钙钛矿结构陶瓷, 并对其进行结构分析和性能测试, 实验结果与理论分析一致, 获得了具有近零频率温度系数的Ca[(Zn_1/3Nb_2/3)_0.7Ti_0.3]O₃介质陶瓷材料. 关键词： B位复合钙钛矿陶瓷 谐振频率温度稳定性 极化机理 6八面体倾斜')" href="#">BO₆八面体倾斜     

气体放电等离子体中多重随机共振实验及数值研究

在气体放电等离子体随机共振实验中观察到了信噪比随噪声强度出现多次共振的现象。这种现象与动力学系统的多稳性质相关。通过对多稳动力学系统随机共振的数值模拟，获得了与实验现象类似的随机共振曲线。     

Dammann光栅在光互连中的应用

本文将Ｄａｍｍａｎｎ光栅［１，２］应用于光互连，提出了用Ｄａｍｍａｎｎ光栅实现完全混洗的方法．一个２×２的Ｄａｍｍａｎｎ光栅与一个成像透镜的组合，具有与四焦点透镜类似的成像作用．像面上，像的位置与Ｄａｍｍａｎｎ光栅的位置有关，适当选择光栅的位置可以实现不同元素数目及不同元素密度的完全混洗．本文给出了有关的理论推导及实验结果．     

从弦振动柯西问题的解法谈学生创新思维的培养

针对学生认识的误区,对于无界弦振动的柯西问题,除了达朗贝尔解法外,给出了傅立叶变换法、拉普拉斯变换法、格林函数法和微分算子法四种解法,并倡议教师在教学过程中要充分利用学生的"好奇"、"好想"、"好动"的心理,采用提问式教学,要求学生一题多解,培养其发散性思维和创造性思维.     

First-Principles Calculations of Electronic Structures of New Ⅲ-Ⅴ Semiconductors： BxGa1-xAs and TlxGa1-xAs alloys

We investigate the electronic structures of new semiconductor alloys BxGa1-xAs and TlxGa1-xAs, employing first-principles calculations within the density-functional theory and the generalized gradient approximation. The calculation results indicate that alloying a small TI content with GaAs will produce larger modifications of the band structures compared to B. A careful investigation of the internal lattice structure relaxation shows that significant bond-length relaxations takes place in both the alloys, and it turns out that difference between the band-gap bowing behaviours for B and TI stems from the different impact of atomic relaxation on the electronic structure. The relaxed structure yields electronic-structure results, which are in good agreement with the experimental data. Finally, a comparison of formation enthalpies indicates that the production Tlx Ga1-xAs with TI concentration of at least 8% is possible.