LBO晶体超光滑表面抛光机理

胶体SiO2抛光LBO晶体获得无损伤的超光滑表面,结合前人对抛光机理的认识,探讨了超光滑表面抛光的材料去除机理,分析了化学机械抛光中的原子级材料去除机理.在此基础上,对胶体SiO2抛光LBO晶体表面材料去除机理和超光滑表面的形成进行了详细的描述,研究抛光液的pH值与材料去除率和表面粗糙度的关系.LBO晶体超光滑表面抛光的材料去除机理是抛光液与晶体表面的活泼原子层发生化学反应形成过渡的软质层,软质层在磨料和抛光盘的作用下很容易被无损伤的去除.酸性条件下,随抛光液pH值的减小抛光材料的去除率增大;抛光液pH值为4时,获得最好的表面粗糙度.     

免疫算法在双闭环直流调速系统中的应用

文中对双闭环直流调速系统控制器的选择进行了分析,并借鉴免疫算法强大的寻优能力,提出了基于免疫算法的调速系统控制器参数整定方法.为了分析比较,实际应用中采用了三种控制器参数整定方法,比较结果说明,免疫算法在调速系统控制器参数整定中的应用是更加有效的.通过在单晶炉拉晶过程的应用,证明该方法可行性和正确性.     

Pyrene分子(小片石墨晶体)的电子传导特性

利用量子理论中基于Green函数的tight-binding方法,对pyrene分子的电子传导和电子流分布进行了理论研究。在考虑到界面耦合和Hopping积分的情况下,得出了电子透射谱和流分布的模拟结果。结果显示透射与电子的能量紧密相关;谱的振荡特征是能级量子化的结果;流分布有着特定的方向,并且在每一个原子点上符合Kirchhoff量子流守恒定律。另外还发现了桥接pyrene分子的正负能开关特性。     

The Optimal Error Estimate of the Fully Discrete Locally Stabilized Finite Volume Method for the Non-Stationary Navier-Stokes Problem

This paper proves the optimal estimations of a low-order spatial-temporal fully discrete method for the non-stationary Navier-Stokes Problem. In this paper, the semi-implicit scheme based on Euler method is adopted for time discretization, while the special finite volume scheme is adopted for space discretization. Specifically, the spatial discretization adopts the traditional triangle P1−P0 trial function pair, combined with macro element form to ensure local stability. The theoretical analysis results show that under certain conditions, the full discretization proposed here has the characteristics of local stability, and we can indeed obtain the optimal theoretic and numerical order error estimation of velocity and pressure. This helps to enrich the corresponding theoretical results.     

在役老旧拱桥的极限承载力分析

在役老旧拱桥的承载力是人们关心的热点问题之一,某些桥梁随着使用年限的不断增加,拱肋以及其他结构部件变形甚至破坏,其承载能力削弱问题会变得尤为突出．以宁波市灵桥为例详细分析了其极限承载力,分析过程中考虑了材料和几何双重非线性,以及涉及到灵桥由于战争、船体碰撞、行车事故和其他意外事故引起的拱肋变形和扭曲情况．计算结果表明：拱肋面外的初始变形极大地削弱了灵桥的极限承载能力;要准确评估该桥的极限承载能力,必须考虑材料非线性和几何非线性的影响．     

基于CMOS图像传感器的成像系统设计

以OV 5 116CMOS图像传感器为例 ,讨论了基于CMOS图像传感器的成像系统的电路设计方法及系统设计中应注意的问题 ;并通过对CMOS图像传感器外围电路的优化设计实现了成像系统的微型化和轻量化。     

复数滤波器在数字全息图处理中的应用

数字全息图在微电路检测、粒度分析、透明场测量等小孔径、小视场对象测量和细胞观测等显微测量方面有着广泛的应用前景。根据离轴数字全息图的频谱特点,提出采用复数滤波器,利用计算机及相关算法对离轴数字全息图进行滤波,消除其零级及共轭像,同时可以得到全息图的相位分布。讨论了复数滤波器的设计方法,给出了实验结果。为数字全息图的压缩、再现和相息图制作提供了方便。     

Non-Invasive Detection of Anti-Inflammatory Bioactivity and Key Chemical Indicators of the Commercial Lanqin Oral Solution by Near Infrared Spectroscopy

Quality control methods of current traditional Chinese medicine (TCM) preparation is time-consuming and difficult to assess in terms of overall efficiency of the drug. A non-destructive rapid near-infrared spectroscopy detection system for key chemical components and biological activity of Lanqin oral solution (LOS), one of the best-selling TCM formulations, was established for comprehensive quality evaluation. Near infrared spectral scanning was carried out on 101 batches of commercial LOS under the penetrated vial state and traditional state. RAW 264.7 cells were cultured to detect the anti-inflammatory ability of LOS, and the reference concentrations of epigoitrin, geniposide, and baicalin were obtained by HPLC. The quantitative models were optimized by three kinds of variable selection methods. The correlation coefficients of prediction value of the models were greater than 0.94. The system also passed the external validation. The performance of the non-invasive models was similar to the traditional models. The established non-destructive system can be applied to the rapid quality inspection of LOS to avoid unqualified drugs from entering the market and ensure drug effectiveness. The biological activity index of LOS was introduced and predicted by NIRs for the first time, which provides a new idea about the quality control of TCM formulations.     

Simultaneous determination of morniflumate and its major active metabolite,niflumic acid,in human plasma by high‐performance liquid chromatography in stability and pharmacokinetic studies

A rapid, sensitive and stable high‐performance liquid chromatography (HPLC) method was developed and validated for the simultaneous determination of morniflumate and its major active metabolite, niflumic acid, in human plasma. HPLC analysis was carried out using a 5 µm particle size, C₁₈‐bonded silica column with a mixture of acetonitrile and 0.005 m potassium phosphate monobasic in water (60:40, v/v) as the mobile phase and UV detection at 287 nm. The method involved the treatment with 50 μL of 0.4 m hydrochloric acid for the stability of morniflumate, extraction with diethylether and evaporation to dryness under a nitrogen stream. The lower limit of quantitation for morniflumate and niflumic acid was 50 and 500 ng/mL, respectively. The calibration curves for morniflumate and niflumic acid were linear over the concentration range of 50–20,000 ng/mL and 500–50,000 ng/mL, respectively, with correlation coefficients greater than 0.9995 and inter‐ or intra‐batch coefficients of variation not exceeding 13.79%. The variability (percentage difference) of incurred sample re‐analysis did not exceed 11.72% and all of the repeat samples fell within 20% of the mean value. This assay procedure was applied successfully to an examination of the pharmacokinetics of morniflumate and its metabolite, niflumic acid, in human subjects. Copyright © 2013 John Wiley & Sons, Ltd.