微结构自由曲面的超精密单点金刚石切削技术概述

回顾了超精密加工技术的发展,主要包括超精密加工设备的开发历程,以及超精密单点金刚石切削技术基础,并对微工程技术作一简要介绍;重点论述微结构自由曲面的微纳切削技术,包括单点金刚石车削(Single point diamond turning, SPDT),快刀伺服加工(Fast tool servo, FTS),金刚石微凿切(Diamond micro chiseling, DMC),光栅铣削等技术。指出微结构自由曲面测量领域面临的挑战和存在的问题,包括接触式测量和非接触式测量。通过几个典型微结构自由曲面的加工及测量的应用进行举例说明;最后介绍我国在超精密加工机床领域内的研制情况,展望了超精密切削技术未来发展趋势。     

Video color conceptualization using optimization

Color conceptualization aims to propagate"color concepts"from a library of natural color images to the input image by changing the main color.However,the existing method may lead to spatial discontinuities in images because of the absence of a spatial consistency constraint.In this paper,to solve this problem,we present a novel method to force neighboring pixels with similar intensities to have similar color.Using this constraint,the color conceptualization is formalized as an optimization problem with a quadratic cost function.Moreover,we further expand two-dimensional(still image)color conceptualization to three-dimensional(video),and use the information of neighboring pixels in both space and time to improve the consistency between neighboring frames.The performance of our proposed method is demonstrated for a variety of images and video sequences.     

芽孢杆菌芽孢内膜脂质的分离及图谱分析

以嗜热脂肪芽孢杆菌为研究对象,针对芽孢内膜脂质难以用传统的Bligh&Dyer方法直接提取的问题,重点分析芽孢脂质的分离过程,并构建了芽孢的脂质图谱.结果表明,碱性蛋白变性剂及溶菌酶能够剥离芽孢外衣、芽孢衣、外膜、肽聚糖等结构,使富含脂质的内膜结构裸露于芽孢表面,荧光染色试验进一步验证了芽孢外层结构剥离的有效性.内膜外露的芽孢用传统方法提取脂质后,用基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)技术进行图谱分析.脂质组学研究表明,嗜热脂肪芽孢杆菌芽孢内膜脂质主要由磷脂酰甘油、磷脂酰乙醇胺及其衍生物、心磷脂组成.     

新型平面磁阻电动机的特性分析

论述了一台应用于工业位置控制的新型平面开关磁阻电动机。该二维电机机械结构简单,性能可靠,并且可以工作在恶劣的环境中。由于该电机具有独特的磁路结构,在x和z方向的互感几乎为零,从而无需引入任何解耦装置。该新型磁阻电机二维运动系统是传统的X-Y工作台理想的替代品,将应用于工业产品自动化的加工和组装领域中。     

THE NONCONFORMING ELEMENT METHOD AND REFINED HYBRID ELEMENT METHOD FOR AXISYMMETRIC SOLID

The general approach for constituting non-conforming displacement function has been developed for axisymmetric finite element analysis and a pure non-conforming quadrilateral axisymmetric element, from a non-conforming displacement function and without any reduced integration technique, is given. Based on a proposed functional for formulating axisymmetric element and the orthogonal approach, a quadrilateral axisymmetric refined hybrid element has been presented which can be used to achieve superior performances such as higher accuracy and free from locking.     

Acid and base effects on the morphology of composites formed from microemulsion polymerization and sol–gel processing

Phase behaviour studies were performed for microemulsions, containing organic monomers (methyl methacrylate and acrylic acid), inorganic monomer (tetraethoxy silane (TEOS)), a cross linking agent (ethylene glycol dimethacrylate) and water, stabilized by a cationic surfactant, cetyltrimethylammonium bromide. Single phase transparent microemulsions were formed over a considerable portion of the composition domain. The effects of an acid, hydrochloric acid (HCl), and a base (NH₄OH) on the gel times were studied and the catalytic action of acid and base on the overall sol–gel reaction was analysed. Organic/inorganic polymer composites were obtained from the hydrolysis and polycondensation reactions of TEOS (sol–gel process) and polymerization of organic monomers and inorganic monomer containing microemulsions. Scanning electron microscopy was used to examine the surface morphology of the composites. For the acid and base studies a precursor microemulsion with pH 7.0 exhibiting closed-cell microstructure upon polymerization was selected. The morphology was examined for polymerized microemulsions with the same base composition but with varying HCl to TEOS ratios or NH₄OH to TEOS ratios. Pore continuity and morphology are strongly influenced by the presence of acid or base. Both the HCl and NH₄OH containing precursor microemulsions led to open celled porous composites. This revised version was published online in November 2006 with corrections to the Cover Date.     

用于手机背光模组的轮廓渐变V-槽形自由曲面结构的新颖设计

目前，市场上流行的手机背光源的导光板基本上为单面网点(球型微透镜阵列)的结构。文章介绍了一种新型手机用导光板的设计，其采用一面为网点结构，另一面为轮廓渐变的V-槽形结构的自由曲面，以使导光板的配光更加合理。模拟结果显示，导光板照度比单面网点的导光板要高出1倍左右。采用这样的结构，背光模组中至少可以少用一层3M公司的增亮膜(棱镜膜)．倬背光樽组的成本有效降低．     

LIPID CONTENT AND FATTY ACID COMPOSITION IN THE GREEN-LIPPED MUSSEL PERNA VIRIDIS (L.)

The lipid content and fatty acid profile in soft tissue of the green-lipped mussel Perna viridis, a widely distributed tropical and subtropical bivalve species, were investigated. The total and neutral lipid contents were 6.17 ± 0.71 and 2.71 ± 0.42 mg per 100 mg dw, respectively. The content of docosahexaenoic acid (DHA, C22:6n-3) was 24.38 ± 2.50 mg/g dw whereas eicosapentaenoic acid (EPA, C20:5n-3) was present at 12.29 ± 2.12 mg/g dw. These two fatty acids were also at the top high percentage among all the fatty acids, with 38.06 ± 0.86% and 17.89 ± 1.24% (w/w) in total lipids and 34.64 ± 2.74% and 20.33 ± 1.05% (w/w) in neutral lipids, respectively. Therefore, green-lipped mussel is a rich source of DHA and EPA, the two n-3 polyunsaturated fatty acids that are beneficial to human health and nutrition.