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《国际聚合物材料杂志》2012,61(6):497-509
Glass fiber reinforced composites based on thermosets are the traditional materials used for many applications due to their good mechanical properties. The non-recyclability of these materials has led to the necessity to develop thermoplastic composites and industrial processes for their manufacture [1]. The present paper deals with the preparation of thermoplastic pre-pregs unidirectionally reinforced with Twarn® and their mechanical characterization. 相似文献
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采用DUO-ICP-AES同时测定精对苯二甲酸中钴、铬、铁、锰、钼、镍、钛,并对仪器的分析线选择、背景校正、入射功率、雾化器压力、辅助气流量、冷却气流量、蠕动泵转速的影响及共存元素的干扰、硝酸铯灰化助剂等因素进行了详细的研究。方法的检测限:钴0.0097 mg/L;铬0.0021 mg/L;铁0.0078 mg/L;锰0.0012 mg/L;钼0.0027 mg/L;镍0.016 mg/L;钛0.0027 mg/L,回收率和精密度分别为93.0%~99.5%和0.37%~3.2%。该方法快速简便,具有良好的精密度和准确度,适用于进出口精对苯二甲酸的日常检验。 相似文献
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The development of new methods for preparing polyfunctional organometallics has made a broad range of such reagents available for various transition metal-catalyzed cross-couplings. An overview of the most general preparation methods will be presented. Applications to practical cross-coupling procedures will be covered, emphasizing the functional group compatibility and the reaction scope. 相似文献
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本文研究了Arizona Chemical公司生产的胎面增强助剂(Tread Enhancement Additive-TEA)Sylvatraxx 4401对半钢子午线轮胎胎面胶性能的影响。结果表明:Sylvatraxx 4401的加入有利于提高白炭黑的分散性,改善混炼胶的加工性能和硫化胶的物理机械性能,能够明显提高胎面的抗湿滑性。随着Sylvatraxx 4401用量的增加,白炭黑在胶料中的分散进一步提高,混炼胶的门尼粘度降低;硫化胶的压缩生热和阿克隆磨耗降低,0oC的tanδ明显提高的同时60oC的tanδ略微降低,有利于胎面胶抗湿滑性能的提高和滚动阻力、动态生热的降低。 相似文献
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Mailadil T. Sebastian Sam Solomon Ravindran Ratheesh Jacob George Pezholil Mohanan 《Journal of the American Ceramic Society》2001,84(7):1487-1489
Microwave ceramic dielectric resonators (DRs) based on RETiNbO6 (RE = Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Y, and Yb) have been prepared using the conventional solid-state ceramic route. The DR samples are characterized using XRD and SEM methods. The microwave dielectric properties are measured using resonant methods and a net work analyzer. The ceramics based on Ce, Pr, Nd, and Sm have dielectric constants in the range 32–54 and positive coefficient of thermal variation of resonant frequency (τf ). The ceramics based on Gd, Tb, Dy, Y, and Yb have dielectric constants in the range 19–22 and negative τf . 相似文献
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R. W. Riemenschneider T. Zell W. E. Scott 《Journal of the American Oil Chemists' Society》1966,43(5):325-326
A series of esters of 12,13-epoxyoleic acid were prepared by means of alcoholysis of triepoxyolein (trivernolin). The procedure
for the alcoholysis, and isolation and purification of the esters are described. Analytical characteristics of the esters
are reported.
E. Util. Res. Devel. Div., ARS, USDA. 相似文献
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ICP-OES测定大量元素水溶肥料中锌、镁、铜、铁、锰、钼、硼含量 总被引:1,自引:0,他引:1
采用ICP-OES对大量元素水溶肥料中微量元素锌、镁、铜、铁、锰、钼、硼进行分析,研究确定了最佳分析条件。加标回收率为96.94%~106.2%,RSD为0.50%~1.40%,检出限为0.001 8~0.218 0 mg/L,方法简便、快速、准确。 相似文献
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Yasuto Fujimaki Minoru Takekawa Shoji Fujisawa Shigeru Ohshima Yohko Sakamoto 《Polycyclic Aromatic Compounds》2013,33(2):107-122
Hexabenzo[a,cd,f,j,lm,o]perylene (HBP), an undecacyclic condensed polycyclic aromatic hydrocarbon with two severely crowded fjord regions, was synthesized by Clar's method; the starting material 8H-benzo[fg]-naphthacene-8-one was newly prepared by the glycerol condensation of 5,12-dihydro-naphthacene-5,12-dione. 1H and 13C NMR spectra of HBP were measured and the chemical shifts were completely assigned. Absorption and fluorescence spectra of HBP were also measured and the effects of nonplanarity on its spectroscopic properties was discussed. 相似文献