The Displacement and Strain Field of Three-Dimensional Rheologic Model of Earthquake Preparation

Based on the three-dimensional elastic inclusion model proposed by Dobrovolskii, we developed a rheological inclusion model to study earthquake preparation processes. By using the Corresponding Principle in the theory of rheologic mechanics, we derived the analytic expressions of viscoelastic displacement U(r, t) , V(r, t) and W(r, t), normal strains epsilon(xx) (r, t), epsilon(yy) (r, t) and epsilon(zz) (r, t) and the bulk strain theta (r, t) at an arbitrary point (x, y, z) in three directions of X axis, Y axis and Z axis produced by a three-dimensional inclusion in the semi-infinite rheologic medium defined by the standard linear rheologic model. Subsequent to the spatial-temporal variation of bulk strain being computed on the ground produced by such a spherical rheologic inclusion, interesting results are obtained, suggesting that the bulk strain produced by a hard inclusion change with time according to three stages (alpha, beta, gamma) with different characteristics, similar to that of geodetic deformation observations, but different with the results of a soft inclusion. These theoretical results can be used to explain the characteristics of spatial-temporal evolution, patterns, quadrant-distribution of earthquake precursors, the changeability, spontaneity and complexity of short-term and imminent-term precursors. It offers a theoretical base to build physical models for earthquake precursors and to predict the earthquakes.

2,4-二取代氨基-6-取代-[1,3,5]三嗪或1,3-嘧啶类化合物、其制备方法、药物组合物及用途

一种新型的2，4-二取代氨基-6-取代-[1，3，5]三嗪或1，3-嘧啶衍生物及其制备方法、药物组合物和其药理用途，其结构通式如式(I)所示，其中R1、R2、R3、R4、R5、R6、A、B、X、Y和Z的定义如说明书中所述。该类化合物与HIV-1整合酶具有很高结合活性，并且在底物竞争测试中能够有效的抑制整合酶对底物的结合。因此该类化合物是较强的HIV-1整合酶抑制剂，有望开发成为新的抗HIV病毒药物。

黑叶猴和菲氏叶猴颅骨的比较研究

用笛卡儿坐标系对黑叶猴和菲氏叶猴颅骨15个坐标点的X、Y和Z值进行了侧 定, 两种叶猴颅 骨的主要差异性区域是面颅和枕骨部。探讨了形态结构差异的 起因。并具体描述了它们的差异表现。图2表2参26

一种生长纳米折叠结构有源区外延片的方法

一种制备具有纳米折叠有源区结构外延片的方法，其特征在于，包括如下步骤:步骤1:先制备AlxInyGazN材料模版，其中x+y+z＝1，0≤x，y，z≤1;步骤2:利用纳米加工技术，在AlInGaN材料模版上制作AlInGaN纳米柱阵列，该AlInGaN纳米柱阵列包括多个AlInGaN纳米柱;步骤3:在AlInGaN纳米柱阵列、AlInGaN纳米柱和AlInGaN材料模版的上表面生长具有纳米折叠结构的有源区层;步骤4:在具有纳米折叠结构的有源区层上生长带有纳米孔阵列的p型GaN层，该p型GaN层填满AlInGaN纳米柱阵列的缝隙，完成外延片的制作。

Electron beam and laser testing on the novel stripixel detectors

The novel Si stripixel detector, developed at BNL (Brookhaven National Laboratory), has been applied in the development of a prototype Si strip detector system for the PHENIX Upgrade at RHIC. The Si stripixel detector can generate X-Y two-dimensional (2D) position sensitivity with single-sided processing and readout. Test stripixel detectors with pitches of 85 and 560 mu m have been subjected to the electron beam test in a SEM set-up, and to the laser beam test in a lab test fixture with an X-Y-Z table for laser scanning. Test results have shown that the X and Y strips are well isolated from each other, and 2D position sensitivity has been well demonstrated in the novel stripixel detectors. (c) 2005 Elsevier B.V. All rights reserved.

关系数据库在CSR准直安装中的应用及CSR测量控制网的设计

国家“九五”重大科学工程项目一兰州重离子加速器冷却储存环工程 CIRFL－CSR），其准直安装由于所涉及的范围大，对元件的定位精度要求极高，所以难度很大．针对工程的特殊要求和具体情况，我们在HIRFL－CSR的准直安装中采取了一系列新的方法和仪器．其中包括建立测量控制网，使用激光跟踪仪进行测量和安装定位．本论文主要介绍了HIRFL－CSR的准直安装的总体方案佩介绍了SMX4500型激光跟踪仪的特点和主要功能佩结合激光跟踪仪的特点，建立了CSR准直安装数据库系统；测量控制网的设计．结合工程的具体特点和仪器的功能，我们拟定了“分层建网，逐段控制”的建网方案．分别设计了CSRm, CSRer前注入线，RIB II各个部分的控制网，以及全局控制网．控制网图用AUTOCAD2000直接在相应的工程图上绘出，再将控制网参数输入到NASEW95中进行平差计算．并且编写了从AUTOCAD2000到NASEW95的数据交换程序，实现了数据交换的自动化．在控制网设计的过程中，采用了方便高效的“自由设站”的方法，和传统的方法相比，用较小的工作量，获得了更多的参加平差的网点．另外，采用了一种特殊形式的闭合延伸导线延伸网，使环上的控制网点的数量减少一半以上，而精度却有所增加。根据激光跟踪仪的特点，建立了一个关系数据库系统，并编写了其前端应用程序，实现了HIRFL－CSR准直安装过程中的数据存储，坐标转换，以及必要的文件格式转换等功能．对于安装定位，采取以下措施：分别建立元件坐标系，局部坐标系和全局坐标系，然后用坐标转换的方法，将不可见的元件磁中心的局部坐标值，转化为安装定位时可用的靶标座的局部坐标值，最后用激光跟踪仪进行安装定位．在安装定位过程中，由于激光跟踪仪可同时监测靶标点的X，Y，Z坐标，所以元件的平面坐标值(X, Y)和竖直方向的坐标值（Z）可同时考虑，一次调整完．改变了传统的准直过程中的元件的水平和平面位置分两次调整的方法．

Photo-induced reactions in the ion-molecule complex Mg+-OCNC2H5

Ion - molecule complexes of magnesium cation with ethyl isocyanate were produced in a laser- ablation supersonic expansion nozzle source. Photo- induced reactions in the 1: 1 complexes have been studied in the spectral range of 230 - 410 nm. Photodissociation mass spectrometry revealed the persistent product Mg+ from nonreactive quenching throughout the entire wavelength range. As for the reactive channels, the photoproducts, Mg+OCN and C2H5+, were produced only in the blue absorption band of the complex with low yields. The action spectrum of Mg+(OCNC2H5) consists of two pronounced peaks on the red and blue sides of the Mg+ 3(2)P <-- 3(2)S atomic transition. The ground state geometry of Mg+ - OCNC2H5 was fully optimized at B3LYP/6- 31 - G** level by using GAUSSIAN 98 package. The calculated absorption spectrum of the complex using the optimized structure of its ground state agrees well with the observed action spectrum. Photofragment branching fractions of the products are almost independent of the photolysis photon energy for the 3P(x,y,z) excitations. The very low branching ratio of reactive products to nonreactive fragment suggests that evaporation is the main relaxation pathway in the photo- induced reactions of Mg+ (OCNC2H5). (C) 2003 American Institute of Physics.

不同基板预热温度对激光金属沉积成形过程热应力影响的研究

研究不同基板预热温度对激光金属沉积成形过程热应力的影响,对于降低成形过程的热应力,抑制成形过程裂缝的产生,减小成形过程试样和基板的翘曲变形具有非常重要的意义。根据有限元分析中的"单元生死"技术,编程建立了基板预热对激光金属沉积成形过程热应力影响的三维多道多层数值模拟模型,详细分析了基板未预热和分别预热到200℃、300℃、400℃、500℃、600℃时对沉积成形过程VonMise’s热应力、X方向、Y方向以及Z方向热应力的影响。在与模拟过程相同的参数下,利用镍基合金粉末分别在基板未预热和分别预热到300℃、400℃、500℃、600℃时进行了成形试验,试验的结果跟数值模拟结果吻合较好。

Molybdenum L-shell X-ray production by 350-600 keV Xeq+ (q=25-30) ions

Molybdenum L-shell X-rays were produced by Xeq+ (q = 25-30) bombardment at low energies from 2.65 to 4.55 keV/amu (350-600 keV). We observed a kinetic energy threshold of Mo L-shell ionization down to 2.65-3.03 keV/amu (350-400 keV). The charge state effect of the incident ions was not observed which shows that the ions were neutralized, reaching an equilibrium charge state and losing their initial charge state memory before production of L-shell vacancies resulted in X-ray production. The experimental ionization cross sections were compared with those from Binary Encounter Approximation theory. Taking into account projectile deflection in the target nuclear Coulomb field, the ionization cross section of Mo L-shell near the kinetic energy threshold was well described. (C) 2010 Published by Elsevier B.V.

用谱方法求解N-S方程

湍流研究具有重要的理论和工程意义,谱方法能达到快速收敛、高效和边界层中高分辨率、高精度。用谱方法边界条件处理也方便,谱方法随着数值方法的改善和计算机系统的发展,它在湍流数值模拟中的作用愈加重要。 这里介绍了一平直槽道及两个同心圆柱间的三维N-S方程数值求解的谱方法,在平直槽道中在平行壁面的x及z方向上用富氏展开,在法向(y)用契比雪夫多项式展开,与平直槽道相似,在θ和z方向用富氏展开,在法向r用契比雪夫多项式展开,为解N-S方程,在时间方向用Crank-Nicholson格式,非线性项用Adam-Bashforth格式,边界和连续条件精确满足。 由平直槽道和二同心圆柱间流动的数值模拟结果表明谱方法是N-S方程数值模拟的有效方法,数值结果与理论结果相符甚好。

Active phase control and frequency chirp effects on supercontinuum generation in high birefringence photonic crystal fiber

An acoustic-optics programmable dispersive filter (AOPDF) was first employed to actively control the linearly polarized femtosecond pump pulse frequency chirp for supercontinuum (SC) generation in a high birefringence photonic crystal fiber (PCF). By accurately controlling the second order phase distortion and polarization direction of incident pulses, the output SC spectrum can be tuned to various spectral energy distributions and bandwidths. The pump pulse energy and bandwidth are preserved in our experiment. It is found that SC with broader bandwidth can be generated with positive chirped pump pulses except when the chirp value is larger than the optimal value, and the same optimal value exists for the pump pulses polarized along the two principal axes. With optimal positive chirp, more than 78% of the pump energy can be transferred to below 750 nm. Otherwise, negative chirp will weaken the blue-shift broadening and the SC bandwidth. (C) 2007 Elsevier B.V. All rights reserved.

Laser-driven inertial ion focusing

A Hohlraum-like configuration is proposed for realizing a simple compact source for neutrons. A laser pulse enters a tiny thin-shelled hollow-sphere target through a small opening and is self-consistently trapped in the cavity. The electrons in the inner shell-wall region are expelled by the light pressure. The resulting space-charge field compresses the local ions into a thin layer that becomes strongly heated. An inward expansion of ions into the shell cavity then occurs, resulting in the formation at the cavity center of a hot spot of ions at high density and temperature, similar to that in inertial electrostatic confinement.

The ultrafast excitation processes in femtosecond laser-induced damage in dielectric omnidirectional reflectors

A pump and probe system is developed, where the probe pulse duration tau is less than 60 fs while the pump pulse is stretched up to 150-670 fs. The time-resolved excitation processes and damage mechanisms in the omnidirectional reflectors SiO2/TiO2 and ZnS/MgF2 are studied. It is found that as the pump pulse energy is higher than the threshold value, the reflectivity of the probe pulse decreases rapidly during the former half, rather than around the peak of the pump pulse. A coupled dynamic model based on the avalanche ionization (AI) theory is used to study the excitation processes in the sample and its inverse influences on the pump pulse. The results indicate that as pulse duration is longer than 150 fs, photoionization (PI) and AI both play important roles in the generation of conduction band electrons (CBEs); the CBE density generated via AI is higher than that via PI by a factor of 10(2)-10(4). The theory explains well the experimental results about the ultrafast excitation processes and the threshold fluences. (c) 2006 American Institute of Physics.

Annealing effects of sapphire substrate on properties of ZnO films grown by magnetron sputtering

The annealing effects of sapphire substrates on the quality of epitaxial ZnO films grown by dc reactive magnetron sputtering were studied. The atomic steps formed on (0001) sapphire (alpha-Al2O3) substrates surface by annealing at high temperature were analyzed by atomic force microscopy. Their influence on the growth of ZnO films was examined by X-ray diffraction and photoluminescence measurements. Experimental results indicate that the film quality is strongly affected by annealing treatment of the sapphire substrate surface. The optimum annealing temperature of sapphire substrates for ZnO grown by magnetron sputtering is 1400 degrees C for 1 h in air.