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981.
针对国内《食品工程原理》本科教材编写的现状,我们提出了需要创新编写思路的问题,从借鉴国际先进的教育指导思想、采用新主线系统化和简化内容、融合创造意识、融合现代计算技术四方面考虑,探索了《食品工程原理》教材编写创新的可能途径。借鉴国际先进的教育指导思想、融合现代计算技术以学习国际先进经验达到编写出新;采用新主线系统化和简化内容、融合创造意识则是主动创新,两者结合可以编写出新的《食品工程原理》教材。 相似文献
982.
Xiong Wei Wu Tomoo Yamamura Suguru Ohta Qi Xiu Zhang Fu Cong Lv Can Ming Liu Kenji Shirasaki Isamu Satoh Tatsuo Shikama Dan Lu Su Qin Liu 《Journal of Applied Electrochemistry》2011,41(10):1183-1190
The redox kinetics of VO2+/VO2 + and V3+/V2+ couples on a carbon paper (CP, HCP030 N, Shanghai Hesen, Ltd., China) electrode were investigated in terms of their standard rate constant (k 0) and reaction mechanism. The values determined for k 0 for VO2+ ?? VO2 + and V3+ ?? V2+ using the CP electrode are 1.0 × 10?3 and 1.1 × 10?3 cm s?1, respectively. The value of k 0 increases by one or two order(s) of magnitude compared with values obtained using electrodes composed of pyrolytic graphite and glassy carbon. The acceleration of the redox kinetics of vanadium ions is a result of the large surface area of the CP electrode. An inner-sphere mechanism for the reaction on the surface of the electrode is proposed. The kinetic features of vanadium redox reactions on the CP electrode reveal that CP is suitable for use as the electrodes in vanadium redox-flow batteries. 相似文献
983.
介绍了雷击的形式及防雷基本技术.分析了山东兖矿峄山化工有限公司受雷击的主要原因,着重介绍了三期尿素装置DCS系统的防雷增强措施. 相似文献
984.
Xiaohui Wang Jun Shi Ying Chen Yan Shi Zhifeng Fu 《Polymer Engineering and Science》2011,51(12):2535-2541
A series of biodegradable aliphatic‐aromatic copolyester, poly(butylene terephthalate‐co‐butylene adipate‐co‐ethylene terephthalate‐co‐ethylene adipate) (PBATE), were synthesized from terephthalic acid (PTA), adipic acid (AA), 1,4‐butanediol (BG) and ethylene glycol (EG) by direct esterification and polycondensation. The nonisothermal crystallization behavior of PBATE copolyesters was studied by the means of differential scanning calorimeter, and the nonisothermal crystallization kinetics were analyzed via the Avrami equation modified by Jeziorny, Ozawa analysis and Z.S. Mo method, respectively. The results show that the crystallization peak temperature of PBATE copolyesters shifted to lower temperature at higher cooling rate. The modified Avrami equation could describe the primary stage of nonisothermal crystallization of PBATE copolyesters. The value of the crystallization half‐time (t1/2) and the crystallization parameter (Zc) indicates that the crystallization rate of PBATE copolyesters with more PTA content was higher than that with less PTA at a given cooling rate. Ozawa analysis was not suitable to study the nonisothermal crystallization process of PBATE copolyesters, but Z.S. Mo method was successful in treatingthis process. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers 相似文献
985.
Fang Mai Dongdong Pan Xiang Gao Meijun Yao Hua Deng Ke Wang Feng Chen Qiang Fu 《Polymer International》2011,60(11):1646-1654
In this work, polyamide 66 (PA66) and its composites with multiwalled carbon nanotubes (MWNTs) were melt spun into fibers at different draw ratios. PA66 fibers at high draw ratio demonstrate a 40% increase in tensile strength, 66% increase in modulus and a considerable increase in toughness. It is demonstrated that this reinforcement can be mainly attributed to high‐draw‐ratio‐induced good dispersion and orientation of MWNTs, particularly the enhanced interfacial adhesion between MWNT and matrix thanks to interfacial crystallization. Our work provides a simple but efficient method to achieve good dispersion and strong interfacial interaction through melt spinning. Copyright © 2011 Society of Chemical Industry 相似文献
986.
Batch experiments were carried out to study the effects of various inorganic anions on the photocatalytic decolorisation of an azo dye (CI Methyl Orange 13025) in the aqueous phase in the presence of cadmium sulphide/polymer nanocomposite films under visible light irradiation. When anion concentrations were low (0.001 m ), the inhibition effect on the photocatalytic decolorisation of CI Methyl Orange 13025 caused by these anions was ranked as . The presence of both and baffled the breakage of the benzene ring in the chemical structure of CI Methyl Orange 13025, while the presence of was of benefit to the degradation of the benzene ring. Adsorption experiments indicated that inorganic anions affected the decolorisation of CI Methyl Orange 13025 by competitive adsorption onto the surface of the photocatalyst. The photocatalytic decolorisation of CI Methyl Orange 13025 followed the pseudo‐first‐order kinetic reaction model well in all experimental cases. 相似文献
987.
Pingan Song Zhenhu Cao Yuanzheng Cai Liping Zhao Zhengping Fang Shenyuan Fu 《Polymer》2011,52(18):4001-4010
Despite the great potential of graphene as the nanofiller, to achieve homogeneous dispersion remains the key challenge for effectively reinforcing the polymer. Here, we report an eco-friendly strategy for fabricating the polymer nanocomposites with well-dispersed graphene sheets in the polymer matrix via first coating graphene using polypropylene (PP) latex and then melt-blending the coated graphene with PP matrix. A ~75% increase in yield strength and a ~74% increase in the Young’s modulus of PP are achieved by addition of only 0.42 vol% of graphene due to the effective external load transfer. The glass transition temperature of PP is enhanced by ~2.5 °C by incorporating only 0.041 vol% graphene. The thermal oxidative stability of PP is also remarkably improved with the addition of graphene, for example, compared with neat PP, the initial degradation temperature is enhanced by 26 °C at only 0.42 vol% of graphene loading. 相似文献
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