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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.
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.
徐士锋  付鹏伟 《化肥工业》2011,38(6):50-52,55
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.
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.
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.
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   
988.
以甲酸为溶剂、相对粘度18.85的超高相对分子质量聚己内酰胺(UHMWPA6)为溶质制备纺丝液,同时加入络合剂CaCl2,通过干法纺丝制备UHMWPA6初生纤维;以水为解络合剂,对初生纤维初拉伸后进行解络合反应,研究了解络合时间对所得纤维的结构及性能的影响.结果表明:随着解络合时间的延长,UHMWPA6初拉伸纤维的断裂...  相似文献   
989.
以碘仿为相对分子质量调节剂,按照国内传统通用型氯丁橡胶(CR)(牌号为CR - 232)的生产配方及工艺条件,对氯丁二烯进行乳液聚合制得CR,考察了碘仿用量对CR综合性能及数均分子量、分子量分布的影响,并与传统调丁型CR - 232的性能加以对比.结果表明,当碘仿质量分数为0.38%,0.40%,0.42%时,除门尼焦...  相似文献   
990.
张艺  许鹏飞  张来  付晓蓉 《广东化工》2011,38(10):5-6,10
采用数值模拟结合实验验证的方法,对聚丙稀(PP)注射成型(保压和不保压)冷却过程实验和数值模拟进行分析。用数据采集器对不同共混物注射冷却过程中的温度变化进行数据采集,并将采集所得温度的实验值与根据改进焓法用Matlab软件对聚丙烯冷却过程中温度分布进行数值模拟计算所得的值进行了比较分析,结果表明聚丙烯在液体冷却段温度分布的实验值与理论值几乎完全吻合,在结晶段和固体冷却段实验值略有不同。  相似文献   
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