X射线聚束透镜原理及其应用

本文阐述了一种新型的Ｘ射线聚束装置─—Ｘ射线透镜的聚束原理。给出了透镜的基本设计方法，并对它应用于Ｘ射线光刻研究领域的前景作了展望。     

第二代农民工市民化与中国共产党执政能力建设

第二代农民工市民化利益要求的实现有助于从阶级基础、群众基础、执政理念、执政资源和执政环境等方面加强党的执政能力建设。在第二代农民工市民化背景下,党应该强化执政为民的理念,构建利益相关制度,强化第二代农民工的工人阶级意识和主人翁意识,鼓励他们积极参与政治生活,有组织、有秩序地进行利益表达,使他们充分享受到城市经济社会发展成果,同时提高党自身的执政能力。     

视觉检测系统中亮度不均匀背景的一种去除方法

刀具形状视觉检测系统中，照明不均匀对测量结果影响很大。针对这种情况，提出了基于二维二阶多项式拟合并去除不均匀背景的方法。遵循最小均方程差原理，给出了二维二阶拟合的矩阵表达式。在编制的程序中，拟合点以人机交互形式由鼠标点击选出，程序自动记录所选点的图象人材与亮度值信息，然后拟合出背景曲面，并以二值图象形式给出去除背景后的目标图象。对一幅光照模型未知的网络图象进行了背景去除，实验结果良好。     

Pumping with electroosmosis of the second kind in mesoporous skeletons

This paper presents the use of mesoporous silica skeletons as substrates for electroosmotic (EO) micropumps. Mesoporous silica skeletons have bimodal pore size distributions consisting of macropores and cation-permselective mesopores. These materials have the potential for high flow rate per power because the cation-permselective mesopores can generate an induced charge layer (ICL) and electroosmosis of the second kind (EO-2) under high applied electric fields. The diffuse charge layers induced by the electric field result in an EO-2 flow rate that increases quadratically with increasing electric field. In contrast, the flow rate of the more common electroosmosis of the first kind (EO-1) is linearly proportional to electric field. Here, we investigate the impact of finite pressure loads on the EO-2 flow rate with experiments and an engineering model to evaluate the potential of mesoporous skeletons for micropumping applications. Our results include analyses of maximum flow rate, maximum pressure, and flow rate with intermediate pressure loads. The results indicate the existence of a critical pressure load at which reverse pressure-driven flow significantly diminishes the EO-2 flow. We also investigate the scaling of flow rate per power with respect to substrate thickness and area, demonstrating significant increases in flow rate per power with thinner substrates and favorable scaling for miniaturization of EO-2 pumps.     

二阶方程稳定性的简易计算判别

很多实际问题都可归结为二阶周期性线性方程,这类方程的稳定性意味着所有解皆为周期解或拟周期解,于是初值如何都对应稳定的周期解或拟周期解。在应用上就说明该实际问题总有稳定运动状态。本文应用Hill方程的一个判别式给出了一个通过简单计算即可判定二阶方程稳定性的方法。数值例子说明该方法具有很好的实用性,同时有较高的精确度。     

几种纳米加工技术的原理、特点及其应用

从整体上介绍了基于传统半导体加工的纳米加工技术、探针直接书写式纳米加工技术、纳米复制加工技术,以及这几种纳米加工技术的原理、特点及其应用。     

Study on electrothermally actuated cantilever array for nanolithography

Nanolithography is a patterning technique for the fabrication of nano-scale structures.A promising method of nanolithography known as scanning probe lithography has particularly extensive applications for its high resolution,high reliability,and simple operation.In this paper,a novel electrothermally actuated cantilever with integrated heater,thermal conductor and actuator for scanning probe lithography is proposed.Cantilevers are designed in an 8×4 array.Analytical models are presented to simulate the temp...     

Accuracy of the zero crossings of the second directional derivative as an edge detector

In this paper the accuracy of the second directional derivative edge detector is analyzed, based on a number of idealized edge models. The results are compared with those for the Laplacian edge detector. Errors are shown to be small under a number of conditions. These conditions are less severe for the second directional derivative than for the Laplacian edge detector. Spurious or phantom edges can be removed by checking the sign of the third directional derivative, though this is not enough to remove all large errors. Indeed, it is also shown that large errors will be obtained if no threshold is set on the magnitude of a third order derivative.This work was supported by the Belgian National Fund for Scientific Research (NFWO).     

LIGA技术的掩模制造

ＬＩＧＡ技术是近几年才发展起来的一门新的技术，包括光刻、电铸和塑铸。由于要进行深度Ｘ光曝光，所用的同步辐射Ｘ光较硬，这一曝光条件相应就需要Ｘ光掩模吸收全有较大厚度和较高的加工精度，这样才能够阻档住Ｘ光，同时保证较高的光刻精度。     

热场致发射电子源曝光系统的技术现状和应用前景

高亮度、长寿命的热场致发射(Thermal field emitter)阴极自七十年代中期已受到人们的关注和重视,历经十多年在理论分析、工艺制备和实验研究上做了大量工作之后,于1988年在电子束曝光机上的应用中取得了突破性进展。用晶向为(100)的钨和具有低逸出功的锆制成的(Zr/O/W)热场致发射阴极在四千小时的使用寿命下亮度值超过六硼化镧阴极一个数量级以上,最近的实验结果表明:在工件台上小束斑下能得到接近两千安培每平方厘米的束流密度,而且四十小时内束流稳定度接近千分之一。显然,这几个表征曝光系统综合技术性能的重要指标,说明多年困扰于各种电子束曝光系统(特别是高斯圆斑电子束系统)在高分辨率情况下生产率较低的技术难题已经得到了比较圆满的解决。 八十年代末期,当热场致发射电子源曝光系统的技术关键解决后,这项技术就成为技术发达国家,特别是美国和日本,在电子束曝光领域进行技术竞争的热点;九一年五月底在美国召开的国际三束会议上有关场致发射阴极和MEBES—4型机已经采用TFE的最新报道充分证实了这项技术在电子束曝光技术应用中的重要地位和发展潜力。