Crystal structures,antibacterial activity and thermal decomposition kinetics of lanthanide complexes with 4-chloro-2-methoxybenzoic acid and 1,10-phenanthroline

A series of lanthanide complexes [Ln(4-Cl-2-MOBA)3phen]2(Ln=Sm(1), Nd(2), Ho(3), Eu(4), Dy(5), and Tb(6); 4-Cl-2-MOBA=4-chloro-2-methoxybenzoate, phen=1,10-phenanthroline) were synthesized and characterized. The single-crystal X-ray diffraction demonstrates that 1–3 are isomorphous, which present dimeric structures with four 4-Cl-2-MOBA anions function as bridging ligands. Complexes 1 and 4–6 display their characteristic luminescence emission bands of central Ln3?ions. The heat capacities, the thermodynamic functions and the thermogravimetry–Fourier transform infrared spectra of gaseous products of complexes 1–6 were investigated.Their non-isothermal kinetics of the second decomposition stage was studied by the integral isoconversional non-linear method and Stark method. Furthermore, 1–6 exhibited excellent antibacterial activity against Candida albicans,Escherichia coli and Staphylococcus aureu.     

三维适形放射治疗犬自发性前列腺增生的扫描电镜观察

目的:研究三维适形放射治疗后前列腺增生组织细胞超微结构的变化,探讨三维适形放射治疗的作用。方法：选择7～15岁老年犬自发性BPH模型10只,随机分为2组。应用3-DCRT直接照射前列腺。以90％的等剂量曲线包绕整个前列腺,单次剂量2Gy,总剂量14Gy,应用6MV-X线完成照射。对照射前、照射后1、3月前列腺组织切片扫描射电镜观察,比较照射前、后组织形态学变化。结果：与照射前比较,照射后扫描电镜下可见,前列腺腺体萎缩,腺体之间间距增大,腺细胞脱落形成空洞。平滑肌萎缩,以纤维组织为主,纤维纤细。结论：3-DCRT可以使腺体和间质萎缩从而缩小前列腺体积改善尿路梗阻和下尿路症状。     

改进的区域解相算法及其在三维重建中的应用

解相位算法是位相三维轮廓测量技术的关键,基于区域的解相位算法是应用较为广泛的解相算法之一。但在实践中发现基于区域的解相算法存在一定问题:当被测物体表面存在阶跃形变结构或噪声较大时可能产生解相错误。通过对该算法解相过程的分析确定了错误产生的原因,并针对存在问题提出一种改进算法,在区域分割的基础上计算每点相位可靠度质量图,并根据计算的二阶差分质量图制定新的区域分割与合并策略对相位进行解算。实验结果表明,本文算法可显著提高基于区域解相算法的解相精度,对表面高度变化较为复杂、噪声较大的相位数据可进行有效处理,具有良好的重建精度和鲁棒性。     

三维场景相息图快速生成研究

相息图以其衍射效率高,无共轭像等优点而被广泛应用于全息三维动态显示中,然而相息图计算量大,生成速度慢而影响了它的实时动态显示;鉴于此,提出了一种三维场景相息图快速生成方法;采用OpenGL进行物点离散采样,逐点计算的优化查表算法进行相息图计算,将相位因子拆成水平方向和竖直方向因子的乘积,离线制作的查找表只需存储水平方向和竖直方向因子,从而使存入GPU纹理内存的查找表空间大大减少,并利用CUDA架构合理设计并行计算方案,使相息图的运算速度进一步加速;实验表明:采用此方法能正确生成所需的相息图,且计算速度比基于CPU的计算方法提高了40倍左右.     

Evaluation of a 3dVAR system for the South China Sea

The authors evaluate a three-dimensional variational （3dVAR） system for the South China Sea （SCS） in this study. The assimilation method applied in the system takes into consideration error correlation along each ground track and uses recursive filter for optimiza- tion. Data from three R/V cruises during the spring and summer of 1998 and the summer of 2000 are used to evaluate the system. The root-mean-square error and bias are reduced significantly and when the altimeter data are assimilated, the distribution of the error is much closer to the Gaussian distribution. Precipitation and river discharge in the southwestern SCS are reproduced, and the variability of sea surface height is efficiently transferred to the subsurface. The 3dVAR system performs well for each of the three cruises, suggesting that it is steady for routine usage.     

CFD simulation of fluidization quality in the three-dimensional fluidized bed

Multiphase computational fluid dynamics （CFD） has become an alternative method to experimental investigation for predicting the fluid dynamics in gas-solid fluidized beds. The model of Brandani and Zhang, which contains additional terms in both the gas- and solidphase momentum equations, is employed to explore homogeneous fluidization of Geldart type A particles and bubbling fluidization of Geldart type B particles in three-dimensional gas-fluidized beds. In this model, only a correlation for drag force is necessary to close the governing equations. Two kinds of solids, i.e., fine alumina powder （dp= 60 μm and pp = 1500 kg/m^3） and sand （dp = 610 μm and pp = 2500 kg/m^3）, are numerically simulated in a rectangular duct of 0.2 m （long） × 0.2 m （wide）× 0.5 m （high） size. The results show good agreement with the classic theory of Geldart.     

三维连续体结构拓扑优化设计数值技术初探

本文分析讨论了三维连续体结构拓扑优化模型,给出了典型结构拓扑优化算例,对结果进行了数值分析。重点对两种常用求解算法的快慢进行比较,并追寻其原因,为提高求解效率指明方向。     

三维数字化技术在翻斗矿车设计中的应用

文章讨论了三维数字化技术在翻斗矿车设计中的应用,并利用UG NX与ANSYS、AutoCAD软件相结合对翻斗矿车进行设计,充分体现了三维数字化技术在机械产品中的应用价值,大大方便地实现产品设计与分析。     

浅析电视节目制作中的虚拟演播室

虚拟演播室是对传统的电视演播室技术的一次重大变革,是一种全新的电视节目制作工具,本文简要探讨了它的应用优势、关键技术和几点思考.     

基于TiO2纳米管的三维LiFePO4正极材料的制备及其电化学性能

本文用TiO_2纳米管阵列作为薄膜锂离子电池的三维模板,通过磁控溅射在TiO_2纳米管上沉积LiFePO_4薄膜,制备出了具有三维结构的LiFePO_4薄膜.结果表明,这种结构的电池不仅增大了LiFePO_4与电解质的接触面积、提高了正极材料的利用率,还有效地缩短了锂离子的迁移路径、弥补了锂离子扩散率低的缺陷,从而改善了电极材料的动力学性能.