丙烯酸酯类无皂LIPN阻尼材料的合成和动态力学性能

采用无皂乳液分步聚合法合成了一系列LIPN阻尼材料，利用动态粘弹谱研究了其动态力学性能。结果表明：网络组分的相容性对阻尼性能的影响显，第三个网络的引入，显地改善了网络组分间的相容性，得到了阻尼性能优良的材料；交联剂用量在一定范围内变化有助于提高涂膜的阻尼性能；通过引入含羧基的共聚组分，提高了材料的高温阻尼性能。     

偶联剂与甘蔗渣／PVC复合材料性能的研究

分别用硅烷偶联剂KH560和钛酸酯偶联剂NDZ311对甘蔗渣/PVC复合体系进行处理。研究了两种处理方法对甘蔗渣/PVC复合材料力学性能、界面形态、耐水性能和加工性能的影响。结果表明,与未处理的相比,两种处理方法都改善了甘蔗渣和PVC之间的界面相容性,界面黏结得到增强,使复合材料的强度和韧性有了较大的提高,同时改善了甘蔗渣/PVC复合材料的加工性能。钛酸酯偶联剂处理对甘蔗渣/PVC复合材料性能的影响更为显著,当其用量为1%时,复合材料的拉伸强度和冲击韧性均得到提高,其中拉伸强度提高了55%。     

Preparation of a self‐compatibility alloy via a seed‐graft concentrated‐emulsion pathway

A novel polymerization procedure, the concentrated‐emulsion graft polymerization of styrene monomer with poly(butyl acrylate) seed, was proposed for the production of a self‐compatibility macromolecule alloy. The effects of the butyl acrylate content, sodium dodecyl sulfate concentration, and polymerization temperature on the graft ratio were investigated. Scanning electron microscopy, transmission electron microscopy, and impact strength were used to characterize the microstructure and mechanical performance of the self‐compatibility macromolecule alloy. The results showed that increasing the butyl acrylate content, reducing the sodium dodecyl sulfate concentration, and improving the polymerization temperature all favored an increased graft ratio, which resulted in increased impact strength of the self‐compatibility macromolecule alloy. Therefore, the concentrated‐emulsion polymerization method is particularly suitable for seed‐graft polymerization. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2915–2920, 2002; DOI 10.1002/app.10288     

SEBS/PP共混材料的研究及其进展

SEBS是一种用途广泛的新型弹性体材料,在常温下具有高弹性,高温下可直接加工成型。由于SEBS具有优异的耐臭氧、耐氧化、耐紫外线和耐候性能等,因此,应用范围广于普通SBS材料。但是,SEBS耐溶剂性和耐油性较差,常通过与其他材料共混改性来增强其加工性能。文章重点概述了苯乙烯-乙烯-丁烯-苯乙烯(SEBS)与聚丙烯(PP)共混材料的微观结构、相容性以及结构与性能的研究进展,介绍了近年国内外SEBS/PP共混改性的研究成果,包括填充油、无机材料、PPO、PC和PA6等改性体系,并比较了这些改性技术对SEBS/PP共混体系微观结构及性能的影响,近年内,SEBS/PP共混材料的理论研究和工程应用会有长足发展。     

某机载雷达发射校正系统的EMC设计

因受载机平台内电子设备电磁干扰的影响,某机载雷达发射校正时存在通道相位漂移的现象,表现为同一通道相位多次测量偏差超过正常幅度值.在阐述发射校正系统工作原理的基础上,深入分析干扰的来源和机理,提出了综合运用屏蔽、接地、滤波等措施解决电磁兼容问题的具体方法,实现了雷达发射校正系统的可靠工作,为该类工程设计提供了参考.     

Compatibility and Properties of Biodegradable Blend Films with Gelatin and Poly（vinyl alcohol）

The blend films with gelatin and poly（vinyl alcohol） （PVA） were prepared by a solution casting method. The compatibility between gelatin and PVA in the blend films was investigated. The transmittance, Fourier-transform infrared spectroscopy （FTIR）, x-ray diffraction （XRD）, thermogravimetry analysis （TG）, and differential scanning calorimetry （DSC） were employed to characterize the resultant blend films. According to optic result, the opacity of the blend film at the ratio of 20/80 （w/w, Gel to PVA） was the lowest, indicating the best compatibility between Gel and PVA at the ratio. The results oflR, XRD, DSC, and TG revealed an intensive interaction and good compatibility between them in the blend film at the ratio. The mechanical properties and solubility showed that PVA content in the blend films obviously affected the elongation at break and solubility. The mechanical properties and water resistance of gelatin film may be improved by the introduetion of PVA.     

Preparation and characterization of PEGDE crosslinked silk fibroin film

To obtain water-insoluble silk fibroin(SF) materials, polyethylene glycol diglycidyl ether(PEG-DE) was selected as a crosslinking agent to prepare SF films(blends). The reaction conditions were optimized for the crosslinking of the SF molecules. The hot water stability of the blends was measured using BCA protein assay and gravimetric analysis. The molecular conformation and crystalline structure of the blends were analyzed by FTIR and XRD, respectively. When the mass ratio of SF:PEG-DE was 1.0:0.8, the hot water loss rate of the SF blends was minimized. PEG-DE could induce SF molecules to form β-sheets during the gel reaction process, resulting in improved crystallinity and hot water dissolved resistance of the blend films. In order to demonstrate the cytotoxicity of the chemical reagents used to crosslink SF, L929 cells were seeded on the blend film(SF:PEG-DE = 1:1) and cultured for 3 days. Cells of L929 readily adhered and spread in the fusiform on the blend film resulting in high cell viability. The extracted liquid from the SF porous film did not inhibit cell proliferation, as estimated by the MTT assay.     

基于FDTD汽车点火系统电磁辐射的研究

电磁兼容是现代汽车设计中的关键及难点问题,点火系统是汽车内电磁辐射干扰的主要激励源,对点火系统电磁辐射计算方法的研究,是汽车电磁兼容问题研究的热点.在推导含电阻元件Yee元胞的时域有限差分法算式的基础上,构建了合理的激励源模式,借助AUTOCAD技术,建立了计算某型号汽车点火系统电磁辐射强度的时域有限差分法模型,并计算出了该型汽车点火系统高压导线在车内产生的辐射电场值.相关工作和结论对汽车电磁兼容问题的分析与预测具有一定的参考价值.     

Preparation and properties of Ce0.8Ca0.2O1.8 anode material by glycine-nitrate process

Ce0.8Ca0.2O1.8（CDC82） anode material was prepared by glycine-nitrate process（GNP）. Thermogravimetric（TG） analysis and differential scanning calorimetric（DSC） methods were adopted to characterize the reaction process of CDC82 material. X-ray diffractometry（XRD）, scanning electron microcopy（SEM）, direct current four probe （four-probe DC） and temperature process reduce（TPR） techniques were adopted to characterize the properties of CDC82 material. After the precursor was sintered at 750℃ for 4 h, CDC82 material with pure-fluorite structure and nanometer size was obtained. The total conductivity of CDC82 changes little with temperature in air at 50-850℃, and the maximum value is 0.04 S/cm at 750 ℃. The total conductivity wholly becomes larger when the atmosphere changes from air to hydrogen, which greatly increases with increasing temperature and reaches the maximum value of 1.09 S/cm at 850 ℃. Some impurities such as CeMg and La203 exist after the mixture of CDC82 anode and La1-xSrxGa1-yMgyO3-δ （LSGM） electrolyte material is sintered at 1 200 ℃ for 15 h. The CDC82 material as anode material has excellent catalytic property for hydrogen and methane.     

几种金属副在NaCl溶液中的抗蚀耐磨性能评价

应用电化学测试手段，针对20、2Cr13、QAl 9-2、QA l 10-3-15和QAl 10-4-4五种材料试件，分别测定了它们在NaCl溶液中的腐蚀电位及与QAl 9-2偶接时的电偶腐蚀电流的变化.并对几种铝青铜材料和QAl 9-2构成的摩擦副进行了摩擦磨损性能分析.结果表明，铝青铜材料的抗腐蚀性比钢好.其中QAl 10-4-4的腐蚀电位最为偏正，但它与QAl 9-2配副会对QAl 9-2产生较大的阳极电偶腐蚀；QAl 9-2与QAl 9-2相配时的电偶腐蚀最小，但其摩擦相溶性最差；而QAl 9-2与QAl 10-3-15材料副的抗电偶腐蚀能力和摩擦相溶性均佳.