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101.
新型菌丝体包覆吸附剂的制备及对Ni2+离子吸附性能的研究 总被引:7,自引:0,他引:7
以菌丝体为核心材料 ,在其表面包覆壳聚糖膜作为吸附介质 ,制备成新型菌丝体包覆吸附剂。系统研究了菌丝体包覆吸附剂的制备工艺及吸附剂对Ni2 + 的吸附特性 ,结果表明 ,菌丝体作核心材料优于花生壳 ,菌丝体包覆吸附剂对Ni2 + 的吸附容量比普通菌丝体水处理剂提高了 50 % ,并可以重复使用 1 0次 ,吸附容量没有明显降低 ;同时菌丝体包覆吸附剂对Ni2 + 的吸附特性较好地符合Langmuir等温方程和Freundlich等温方程 相似文献
102.
4G时代的到来给智能电视行业带来了极大的变革.如何有效利用4G技术,迎接新技术带来的机遇和挑战,成为智能电视企业发展的重要课题.结合4G技术发展带来的行业变革,调查了智能电视商业模式现状,并有针对性地提出了智能电视商业模式的发展措施. 相似文献
103.
全业务运营时代给运营商带来了运营模式的巨大变革,从原有的产品化营销理念,逐步走向了市场化营销理念,传统的运营支撑手段已不能满足市场运营的发展需求。基于对实际问题的研究,本文提出一种新型的运营支撑流程化管理模式。 相似文献
104.
Hai Huang Haichao An Wenrui Wu Lingyan Zhang Beibei Wu Weipeng Li 《Structural and Multidisciplinary Optimization》2014,50(5):883-898
According to the mission of a satellite with maneuver capability, the collaborative optimization (CO) method was introduced for the satellite system design, and the related multidisciplinary design optimization (MDO) model was established. The possessing and needed velocity increments Δv and Δv n e e d were taken as the measurement of maneuvering capability of the studied satellite, which were then combined with total mass of the satellite to form the optimization objective in the systematic level of the MDO problem. The design variables and constraints of the MDO problem dealt with disciplines or subsystems as guidance, navigation and control (GNC), power, and structure, and corresponding engineering analysis models were also built. A program system to solve the MDO problem wasdeveloped by integrating a non-nested CO method, the commercial and user-supplied codes on framework software iSIGHT. The result showed that the satellite performance could be obviously improved, which also indicates MDO technique is feasible and effective for the spacecraft design problem. The modeling and optimization procedure of the work can be referred for further research and engineering design. 相似文献
105.
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107.
Hai -Hang Li Masafumi Inoue Hiroyuki Nishimura Junya Mizutani Eiji Tsuzuki 《Journal of chemical ecology》1993,19(8):1775-1787
Phenolic compounds have been identified as the most common allelochemicals produced by higher plants. Inhibitions of cinnamic acid, its related phenolic derivatives, and abscisic acid (ABA) on seedling growth and seed germination of lettuce were studied.trans-Cinnamic acid, ando-,m-, andp-coumaric acids inhibited the growth of etiolated seedlings of lettuce at concentrations higher than 10–4 M and seed germination above 10–3 M. Coumarin inhibited seedling growth and seed germination at 10–5 M or above. Chlorogenic acid inhibited seedling growth above 10–4 M, but did not inhibit seed germination at 10–5–5×10–3 M. Low concentrations (below 10–3 M) of caffeic and ferulic acids promoted the elongation of hypocotyls, but higher concentrations (over 10–3 M) inhibited seedling growth and seed germination. These phenolic compounds and abscisic acid had additive inhibitory effects both on seedling growth and seed germination. The inhibition on lettuce was reversed by caffeic and ferulic acids at concentrations lower than 10–3 M except for the inhibition of germination by coumarin. These results suggest that in naturetrans-cinnamic acid,o-, m-, p-coumaric acids, coumarin, and chlorogenic acid inhibit plant growth regardless of their concentration. However, caffeic and ferulic acids can either promote or inhibit plant growth according to their concentration. 相似文献
108.
有机累托石改性不饱和聚酯/玻璃纤维复合材料的研究 总被引:2,自引:0,他引:2
采用有机累托石改性不饱和聚酯,以改性的不饱和聚酯为基体,以两种玻璃布(EW210、CWR400-90)为增强材料,以两个不同凝胶时间的不饱和聚酯树脂体系制备三种有机累托石改性的不饱和聚酯磁璃纤维复合材料(UPB1、UPB2、UPB3)。测试了不饱和聚酯/玻璃纤维的力学性能;研究了复合材料的耐湿热性及耐介质性能;利用扫描电镜及透射电镜分析了复合材料的增强机理。结果表明,采用有机累托石改性不饱和聚酯所制备的不饱和聚酯/玻璃纤维复合材料的综合力学性能优于纯不饱和聚酯/玻璃纤维复合材料。 相似文献
109.
In this study, a series of T300 carbon fiber‐reinforced polyimide (CFRPI) composites were prepared by laminating premolding polyimide (PI) films with unidirectional carbon fiber (CF) layers. On the basis of PI systems design, the effect of CF volume fraction, processing conditions, and PI molecular structure on the properties of CFRPI composites was studied in detail. In addition, two kinds of nano‐particles, including carbon nano‐tube (CNT) and SiO2 were filled into the premolding PI films with different concentrations. And the effect of nano‐particles on the properties of CFRPI composites was also investigated. The surface characteristic of T300 CF was measured by X‐ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The properties of premolding PI film and CFRPI composites were measured by dynamic mechanical analysis (DMTA), SANS testing machine, scanning electron microscopy (SEM), and so forth. These experimental results showed that the properties of CFRPI composites were mainly affected by the premolding PI film and molding condition. The change of CF volume fraction from 55% to 65% took little effect on the mechanical properties of CFRPI composites. In addition, the incorporation of nano‐particle SiO2 could further improve the properties of CFRPI composites, but CNT hardly improved the properties of CFRPI composites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 646–654, 2006 相似文献
110.
采用系统分析、数学及物理计算的方法,对火电厂仪用压缩空气带水带油的原因进行论证,找出最主要原因,并有针对性地采取了预防和改造措施,对改造效果进行了分析与总结。 相似文献