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111.
通过实验分析确立了把光纤电阻作为衡量气密性碳涂覆光纤通过2%应变筛选的过渡标准。要拉制2%应变筛选的碳涂覆光纤,其电阻值应小于30kΩ/cm。 相似文献
112.
线圈型全光纤偏振器的研究 总被引:2,自引:0,他引:2
本文采用等效电流法对线圈型全光纤偏振器进行了分析计算.对应于保偏光纤中两正交传输基模的消光比,提出了一种分析保偏光纤弯曲损耗的新方法,这种方法基于将保偏光纤两个不同偏振模式分别等效为两个普通圆光纤的基模,等效参数通过测量不同偏振模式的模场半径来确定.实验证明这种理论计算方法与实验结果一致.最终,我们研制出的线圈型光纤偏振器在1.31μm工作波长下,实测消光比达30dB以上,工作偏振模式插入损耗≤3dB. 相似文献
113.
114.
报道了FTS-20F富里叶红外光谱仪数据系统改造的工作采用IBM486计算机及新的数据接口取代了陈旧的NOVA4数据系统,文章详细描述了其硬件设计和软件编辑,改造不仅更新了FTS-20E里叶红外光谱仪,而且还使其达到90年代的水平。 相似文献
115.
毛细管电泳安培检测扑热息痛及其水解物 总被引:1,自引:0,他引:1
研究了各种电化学预处理条件下碳纤维电极对扑热息痛及水解物的电化学行为。确定该体系最佳预处理条件为0.2V电位下阳极化1min,再于-2.0V下阴极化10s。预处理后的碳纤维伏安响应得到明显提高。运用最佳条件并在支持电解中加入添加剂后,扑热息痛及其水解物在毛细管电泳上获得很好的分离和检测。其中扑热息痛的检测下限为2.78pg;对氨基酚为1.84pg。 相似文献
116.
Michael Binnewies Marion Jerzembeck Andreas Kornick 《Angewandte Chemie (International ed. in English)》1991,30(7):745-753
One of the modern high technologies which has advanced enormously in the last few years is glass fiber technology. This is used in the manufacture of glass fibers for lighting purposes and for the optical transfer of analog and digital data with a high transfer density. The technical demands made on the glass fibers required for data transfer, the optical waveguides, are extremely high and are already fulfilled to a large extent by industry. At present about four million kilometers of fiber, worth ca. 800 million DM are produced worldwide (10% in the Federal Republic of Germany). Numerous chemical processes take place during the manufacture of optical waveguides. However, in contrast both to the high and constantly growing demands on the quality and to the increasing production volume of such fibers, little is in fact known about the reactions involved. The present article will attempt to develop a picture of the multifarious reactions occurring in the course of this technical process on the basis of literature data and our own studies. 相似文献
117.
Fa Jie Yang Da Ling Yang Shou Hai Zhang Xi Gao Jian 《中国化学快报》2007,18(8):966-968
A new interfacial polymerization (IP) procedure is developed in order to synthesize polypiperazine-amide thin-film membrane on the inner surface of poly(phthalazinone ether sulfone ketone) (PPESK) hollow fiber ultrafiltration (UF) membrane.A hollow fiber composite membrane with good performance was prepared and studied by FT-IR and scanning electron microscopy. 相似文献
118.
A study of migration of the active components of oxygen sensors into food is presented. Six types of sensors, based on different oxygen sensitive dyes (two metalloporphyrins and one ruthenium dye), polymers (polystyrene and polysulfone) and support materials, were exposed to a number of standard ‘food simulants’ recommended by FDA/EU guidelines and then assayed for migration or sensor components and changes in oxygen calibration. Both metalloporphyrin sensor dyes leached only in olive oil and in 95% ethanol (used as a positive control), at maximum levels of 19.22 μg/dm2 for PtOEPK and 113.96 μg/dm2 for PtTFPP. The RuDPP dye showed maximum leaching in 95% ethanol (25.19 μg/dm2) while also migrating in an acidic aqueous simulant. Planar supports such as polyester tended to enhance the stability of the sensor. Migration of the styrene monomer from the polystyrene encapsulation medium was concluded to be low enough to be insignificant. Migration of sensor components was shown to correlate with the changes in sensor response to oxygen. Based on these results, sensor combinations were ranked on the basis of their resistance to leaching and their general stability, safety and suitability for use on a large scale in packaged foods and related food applications was proven. 相似文献
119.
Organic chelating reagent influences upon the redox adsorption of activated carbon fibertowards Au3- were systematically investigated. The experimental results indicated that the presenceof organic chelating reagent on activated carbon fiber strongly affects adsorption capacity ofactivated carbon fiber towards Au3+. The reduction-adsorption amount of Au3+ increased three timesby the presence of 8-quinolinol. Furthermore, The reduction-adsorption amount of Au3+ depended onthe pH value of adsorption and temperature. 相似文献
120.