基于截面特征相容的曲面约束重构

为了从点云中重建高品质的曲面模型,提出一种基于截面特征相容的曲面重构方法.该方法将由点云切片获取的截面曲线分层次表达为直线、圆弧、B样条等基本曲线元和特征点的集合,并基于曲线微分几何属性,建立截面曲线特征点对应的数学模型,采用动态规划法求解并确定其初始对应关系,以曲线元特征匹配准则优化对应,逐步确立截面曲线间的特征对应关系,将特征对应关系映射为参数对应即可利用成熟算法逼近生成蒙皮曲面.实例表明,该算法获取的曲面模型不但满足精度和光顺性要求,而且忠实地反映了原始物理样件所蕴含的特征信息.     

变频调速传动系统的电磁兼容分析

在变频调速传动系统中,变频器会产生和受到各种电磁干扰。本文分析了变频调速传动系统的主要电磁干扰源和耦合途径,并阐述了抑制其电磁干扰的措施。     

Structure and blood compatibility of tetrahedral amorphous hydrogenated carbon formed by a magnetic-field-filter plasma stream

Tetrahedral amorphous hydrogenated carbon (ta-C:H) films with various substrate bias voltages were prepared using a magnetic-field-filter plasma stream deposition system. The microstructural and optical properties were studied using ellipsometric spectra. The refractive index n of each sample was obtained by simulating their ellipsometric spectral using Tauc-Lorentz oscillator model, and then the relative sp³ C ratio of each sample was calculated using Bruggeman effective medium approximation. The sp³ C fraction of each sample was quantified by using electron energy-loss spectroscopy (EELS). The blood compatibility of the samples was evaluated by tests of platelet adhesion, kinetic clotting time and thrombin time. The quantity and morphology of the adherent platelets on the surface of these samples were investigated using scanning electron microscopy. Results show that the spectroscopic ellipsometry is a helpful method to evaluate the sp³ carbon fraction of the carbon films. The substrate bias voltage has an obvious effect on sp³ content and blood compatibility of ta-C:H films. The sample prepared with substrate bias voltage of − 20 V showed the best blood compatibility. A simple bio-physical hypothetical model was proposed to explain the experiment results.     

国内弧焊设备电磁兼容性研究进展

焊弧设备的电磁兼容性问题日益突出，受到越来越多的关注。针对我国的实际情况，对国内弧焊设备的研究现状进行了综合分析，同时指出了今后的研究方向。     

沥青聚氨酯防水涂料的发展概述

简要介绍了沥青聚氨酯防水涂料的现状、配方设计、性能及应用,并探讨了沥青与聚氨酯的相容性问题。     

用单一非等温DSC曲线评价FAE复合燃料内相容性的研究

尝试了用炸药组分的单一非等温DSC曲线来确定一次引爆型FAE复合燃料的热分解动力学参数，并据此来评价该复合燃料的内相容性。通过对比可以发现，该方法处理的结果与传统的Ozawa方法处理结果误差很小。实验结果也表明一次引爆型FAE药剂具有良好的内相容性。     

Carboxyl‐terminated butadiene–acrylonitrile rubber modified cyanate ester resin

The carboxyl‐terminated butadiene‐a‐acrylonitrile rubber (CTBN) has been proved to be the most effective toughener for cyanate ester (CE) resin. This work mainly focuses on the different modification effects caused by the addition of CTBN with different acrylonitrile content. The phase separation, morphology of fracture surface, and physical properties of the blends are studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic mechanic analysis (DMA), and thermogravimetric analysis (TGA). It is testified that the compatibility and toughness between CE and CTBN had a positive correlation with the acrylonitrile content of CTBN. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

MAH接枝EPDM增韧PA66的研究

研究了MAH(马来酸酐)接枝三元乙丙橡胶(EPDM—g-MAH)对尼龙66(PA66)的增韧作用。利用SEM(扫描电镜)观察了共混体系的微观形貌(形态结构)，并运用小角激光散射(SALS)方法研究了EPDM的加入对PA66结晶性能的影响。结果表明，未接枝的EPDM与PA66的相容性很差，而EPDM—g—MAH与PA66相容性明显增加，EPDM-g—MAH粒子均匀分散在PA66中，共混体系力学性能有很大提高。随着EPDM—g—MAH用量的增加，PA66球晶尺寸变小，共混体系界面结合更加紧密。     

飞行器电磁窗耐雨蚀复合涂层的制备

研制了电磁窗用耐雨蚀底漆和耐雨蚀面漆，介绍了该配套涂料体系的制备工艺，并列举了其性能指标。讨论了耐雨蚀面漆中聚酯树脂、多元醇和颜料对其性能的影响，施工工艺对耐雨蚀涂层与底涂层之间配套性能的影响。     

镀锌层与氟碳漆涂层的相容性研究

在部分产品中,钢表面镀锌后表面再涂一层漆,其目的是为了增加耐腐蚀性能。但是锌可能会与漆层中的一些组份发生反应,降低漆膜性能。本文通过开展氟碳漆涂层和镀锌层湿热试验后性能测试研究,表明两者之间具有较好的相容性,可提高产品的防护性能。