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71.
In this work, the kinetics of the polyvinyl butyral (PVB) synthesis reaction catalyzed by the deep eutectic solvents (DESs) at the low-temperature stage was studied to control the particle size of PVB resin and optimize its synthesis process. The effects of stirring speed, the concentration of polyvinyl alcohol (PVA), catalyst dosage, and temperature on the synthesis reaction of PVB were investigated. The data obtained from kinetic experiments at 283.15–298.15 K were fitted with the shrinking core models, and the results showed that the model controlled by internal diffusion fitted well with the experimental data. The internal diffusion coefficient, DA, of n-butanal in the product layer was further calculated by the obtained model parameters, and it was applied to predict the synthesis reaction of PVB at different concentrations of n-butanal. The results indicated that the shrinking core model controlled by internal diffusion is suitable to describe the kinetics of the PVB synthesis reaction. DES played a dual role in catalysis and dispersion in the synthesis of PVB, and it was a green catalyst with good potential for PVB industrial applications.  相似文献   
72.
Hydrogen (H2) purification requires separation membranes with excellent performance and high stability. Here, a few nanometer-sized Zr-oxygen clusters (CP-2) abundant in amino groups were incorporated in benzimidazole-linked polymers (BILPs) by interfacial polymerization (IP) to fabricate molecular-scale hybrid membranes for efficient H2/CO2 separation. The amino groups in CP-2 engage in IP. The structure of the BILPs polymer chains is regulated and more H2 selective channels are created. The hybrid membranes provide an H2/CO2 selectivity of up to 75.2 (with a corresponding H2 permeance of 318 GPU) and a high H2 permeance of up to 1470 GPU (with a corresponding H2/CO2 selectivity of 23.6). In addition, the membranes exhibit satisfactory separation performance and durability under industry-relevant conditions (573 K, 11 bar, or steam treatment).  相似文献   
73.
基于深圳市电镀、印制电路板行业存在的环境问题及环境风险现状,结合国家相关技术指南及导则,提出建立一种电镀、印制电路板行业环境风险评价指标体系,为深圳市试点环境污染责任险制度提供技术支持.  相似文献   
74.
A high‐temperature lubricant genioplast pellets (GPPS) was used in order to improve the processing behavior of poly(ether ether ketone) (PEEK) resin and high‐performance PEEK fibers were produced by melt‐spinning. The rheological properties of spinning material, morphology, mechanical, and thermal properties of PEEK fibers were characterized by using a polymer capillary rheometer, scanning electron microscopy, single fiber electronic tensile strength tester, wide‐angle X‐ray diffraction and thermal gravimetric analyzer, respectively. The results indicated that the introduction of lubricant GPPS decreased the melting viscosity of PEEK resin and improved spinnability of PEEK resin without sacrificing its thermal properties. The filaments are cylindrical with smooth surface and uniform diameter. The optimized content of GPPS was determined to be 1.0 wt% by balancing the decreased torque and changes of the mechanical properties. The strength and modulus of PEEK fibers were 420 MPa and 3.6 GPa, respectively. This should be due to the improvement in spinnability, followed by the enhancements in the orientation and crystallization of PEEK fibers in the process of drawing and annealing. POLYM. ENG. SCI., 53:2254–2260, 2013. © 2013 Society of Plastics Engineers  相似文献   
75.
Dyes have been applied and are playing an increasingly important role in many industries, including the textile, printing, medical and energy industries. Their wide applications imply that specific dyes possessing given properties need to be effectively designed. The present review aims to survey information related to activity/property research of dyes that has been published in the past two decades. Emphasis is laid particularly on studies based on quantitative structure–activity/property relationships that have contributed to the theoretical design and application of dyes. Finally, the perspectives of quantitative structure‐activity/property relationship studies are set out in order to show how this method may be used to design new dyes and to evaluate their different properties. The challenges facing these studies are also outlined.  相似文献   
76.
二碘化钐在分子内环化反应中的应用   总被引:1,自引:0,他引:1  
于鸾  余明新  张永敏 《化学试剂》2005,27(10):597-600
综述了二碘化钐在分子内环化反应中的应用。  相似文献   
77.
分析8279芯片的显示接口及十六段和八段LED显示驱动电路的特点,提出了十六段和八段LED混合显示驱动的方法,并介绍了一种经济、实用的显示驱动电路。  相似文献   
78.
新型高强韧性奥—贝组织低合金钢的研究   总被引:2,自引:0,他引:2  
作者应用新的合金设计思想,研制了一类新型高碳低合金超高强度钢。经适当热处理,获得贝氏体铁素体板条与奥氏体薄膜交替排列的奥氏体-贝氏体双相组织。文中研究了钢的组织、力学性能及其与转变温度的关系。  相似文献   
79.
本文概括了新型功能材料——贮氢材料的发展状况和应用研究进展,重点综述了稀土储氢合金性能改善方面的最新成果和用于二次电池的贮氢材料的状况。  相似文献   
80.
通过溶胶一凝胶法制备了中空石英纤维增强石英基体的多孔陶瓷隔热材料,进行了力学和热物理性能测试,结果表明:材料密度0.95g/cm^3,常温下的导热系数0.135W/m·K,材料具有质量轻、强度高、隔热性能好及耐高温(1200℃)的特点。  相似文献   
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