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91.
中式快餐发展战略与人才培养 总被引:2,自引:0,他引:2
本文讨论了我国快餐业的发展现状,进一步研究中式快餐发展战略,以及中式快餐业有关人才的培养现状和满足发展各类人才培养途径。 相似文献
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Organic‐acid‐catalyzed sol–gel route for preparing poly(methyl methacrylate)–silica hybrid materials
Jui‐Ming Yeh Kuan‐Yeh Huang Chung‐Feng Dai B. G. Chand Chang‐Jian Weng 《应用聚合物科学杂志》2008,110(4):2108-2114
In this study, a series of organic–inorganic hybrid sol–gel materials consisting of a poly(methyl methacrylate) (PMMA) matrix and dispersed silica (SiO2) particles were successfully prepared through an organic‐acid‐catalyzed sol–gel route with N‐methyl‐2‐pyrrolidone as the mixing solvent. The as‐synthesized PMMA–SiO2 nanocomposites were subsequently characterized with Fourier transform infrared spectroscopy and transmission electron microscopy. The solid phase of organic camphor sulfonic acid was employed to catalyze the hydrolysis and condensation (i.e., sol–gel reactions) of tetraethyl orthosilicate in the PMMA matrix. The formation of the hybrid membranes was beneficial for the physical properties at low SiO2 loadings, especially for enhanced mechanical strength and gas barrier properties, in comparison with the neat PMMA. The effects of material composition on the thermal stability, thermal conductivity, mechanical strength, molecular permeability, optical clarity, and surface morphology of the as‐prepared hybrid PMMA–SiO2 nanocomposites in the form of membranes were investigated with thermogravimetric analysis, differential scanning calorimetry, dynamic mechanical analysis, gas permeability analysis, ultraviolet–visible transmission spectroscopy, and atomic force microscopy, respectively. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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Sodium sulfonate‐terminated dendritic poly(ester‐amine) (SPEA) was synthesized by sulfonation of acrylic double bond‐terminated dendritic poly(ester‐amine) (APEA) with sodium hydrogen sulfite (NaHSO3) in mixture of diglycol and 2‐butanone under normal pressure. The structure of SPEA was characterized by IR, 1H‐NMR, and elemental analysis. SPEA was water‐soluble. 1.0–40.0% (mass) SPEA aqueous solutions appeared as dilatant fluid. When pH value varied from 1.5 to 12.0, the viscosity of 1–5% (mass) SPEA aqueous solutions changed very small, and the electric conductivity almost kept stable within pH 3.0–10.0. The relationship between the viscosity and the concentration of SPEA water solutions was similar to that of NaCl water solutions. The surface tension of SPEA water solutions was lower than that of polyethylene glycol 2000 water solutions with the same concentration. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
96.
Degumming of hemp fiber by high temperature alkali cooking was investigated, and the effect of temperature and dosage of alkali on the constituents, structure, and thermal degradation of hemp fiber was also discussed in this work. The morphology, structure, and thermal degradation of hemp fiber after high temperature cooking were investigated through SEM, FTIR, WAXD, and TG analysis. The results indicated that the high temperature cooking process was effective for removing hemicelluloses and lignin and could also improve the thermal stability of cellulose. Crystallinity index of the treated hemp fiber was increased, which was related to the cooking temperature and NaOH dosage. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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利用智能数显仪的万能输入、变送输出和控制输出功能,不仅可以实现加热站采暖温度根据大气温度自动调节的方案,而且通过改进可以实现硝酸透平压缩机轴位移联锁控制和应用于制作栲胶溶液槽上的液面计. 相似文献
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对烧结法和拜尔法种分槽的Δαk 变化进行了概述 ,阐述了精液Al2 O3 浓度关系到晶种分解的产出率、分解率、氢氧化铝粒度及系统的液量平衡、能耗等 ,生产中要把握这些影响因素 ,确保氢氧化铝晶体的长大速度为正值。 相似文献
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