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991.
Jyh‐Chien Chen Kuppachari Rajendran Ya‐Hui Chang Sheng‐Wen Huang Yaw‐Tern Chern 《应用聚合物科学杂志》2011,120(6):3159-3170
Polypyrrole (PPy) and Polypyrrole‐ZnO (PPy‐ZnO) nanocomposites were electrodeposited on mild steel and its corrosion protection ability was studied by Tafel and Impedance techniques in 3.5% NaCl solution. Pure Polypyrrole film was not found to protect the mild steel perfectly but the coating with nano‐sized ZnO (PPy‐ZnO) has dramatically increased the corrosion resistance of mild steel. Electrochemical Impedance Spectroscopy (EIS) measurements indicated that the coating resistance (Rcoat) and corrosion resistance (Rcorr) values for the PPy‐ZnO nanocomposite coating was much higher than that of pure PPy coated electrode. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
992.
In this study, various polypropylene (PP) nanocomposites were prepared by melt blending method. The effects of different spherical nanofillers, such as 50 nm CaCO3 and 20 nm SiO2, on the linear viscoelastic property, crystallization behavior, morphology and mechanical property of the resulting PP nanocomposites were examined. Rheological study indicated that coincorporation of nano‐SiO2 and nano‐CaCO3 favored the uniform dispersion of nanoparticles in the PP matrix. Differential scanning calorimeter (DSC) and polarizing optical microscopy (POM) studies revealed that the coincorporation of SiO2 and CaCO3 nanoparticles could effectively improve PP crystallizability, which gave rise to a lower supercooling temperature (ΔT), a shorter crystallization half‐life (t1/2) and a smaller spherulite size in comparison with those nanocomposites incorporating only one type of CaCO3 or SiO2 nanoparticles. The mechanical analysis results also showed that addition of two types of nanoparticles into PP matrix gave rise to enhanced performance than the nanocomposites containing CaCO3 or SiO2 individually. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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995.
Mei‐Rong Huang Sheng‐Xian Li Zhi‐Qing Dong Wei Feng Xin‐You Wang Shu‐Ying Gu Yan‐Hui Wu Xiang‐An Huang 《应用聚合物科学杂志》2002,83(14):3013-3021
Several multilayer thin low‐density polyethylene (LDPE) films were fabricated by blown thin film having a thickness of 7 μm and an area of 130 cm2. They were characterized for their oxygen‐enrichment performance from air by a constant pressure–variable volume method in a round permeate cell with an effective area of 73.9 cm2. The relationship between oxygen‐enrichment properties, including oxygen‐enriched air (OEA) flux, oxygen concentration, permeability coefficients of OEA, oxygen, nitrogen, as well as separation factor through the multilayer LDPE films, and operating parameters, including transfilm pressure difference, retentate/permeate flux ratio, temperature, as well as layer number, are all discussed in detail. It is found that all of the preceding oxygen‐enrichment parameters increase continuously with an increase of transfilm pressure difference from 0.1 to 0.65 MPa, especially for the trilayer and tetralayer LDPE films. The oxygen concentration and separation factor appear to rapidly increase within the retentate/permeate flux ratio below 200, and then become unchangeable beyond that, whereas the OEA flux and the permeability coefficients of OEA, oxygen, and nitrogen seem to remain nearly constant within the whole retentate/permeate flux ratio investigated, especially for the monolayer and bilayer LDPE films. The selectivity becomes inferior, whereas the permeability becomes superior, as the operating temperature increases from 23 to 31°C. The highest oxygen concentration was found to be 44.8% for monolayer LDPE film in a single step with air containing oxygen of 20.9% as a feed gas and operating pressure of 0.5 MPa at a retentate/permeate flux ratio of 340 and 23°C. The results demonstrate a possibility to prepare an oxygen‐enriching membrane directly from air, based on the easily obtained thin LDPE films. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 3013–3021, 2002; DOI 10.1002/app.2331 相似文献
996.
研究了用超临界CO2 流体技术从香兰豆荚中萃取香兰素的工艺条件 ,探索了萃取压力、温度、时间对萃取率的影响 ,结果表明 ,超临界CO2 萃取香兰素的工艺切实可行 ,最佳萃取条件是萃取压力为 35 0bar、温度为 4 5℃、时间为 14 0min ,在此萃取条件下每克香兰豆荚的香兰素萃取量为 2 0 .0 5mg ,萃取率为 98.5 %。 相似文献
997.
半导体单色(红)光光催化模拟合成三磷酸腺苷研究 总被引:1,自引:0,他引:1
以半导体材料 (Zn·Cd)S :Ag KI为催化剂 ,在单色 (红 )光光照下 ,成功地模拟了光合作用的光合磷酸化 ,研究了红光的光照度、照光时间、二磷酸腺苷 (ADP)浓度及催化剂量等对三磷酸腺苷 (ATP)合成的影响。最佳条件为 :光照度 30 2 2Lx ,照光时间 1h ,半导体粉量 2 5 0mg ,Na2 HPO42 0mmol/L ,MgCl2 3.1mmol/L ,K3 Fe(CN) 62 .0mmol/L ,ADP浓度为 0 1mmol/L ,转化率平均可达到 3 6 %。 相似文献
998.
采用线形扫描伏安法和循环伏安法研究了抗癌新药氟哌酸基甲硫酰 (1 苯基甲撑 ) 肼 (F2 )的电化学行为。实验结果表明 ,F2 在电极表面存在吸附特性 ,在 0 0 5mol/L的NH3 NH4Cl缓冲溶液中 ,该药物在- 0 73V(vs.SCE)处有一灵敏的还原峰 ,在选定的最佳条件下 ,其浓度在 (0 2~ 4 0 )mol/m3 之间时与其峰电流有良好的线形关系 ,检测限为 0 0 5mol/m3 。方法用于检测模拟尿、血清样品中痕量药物的测定 ,回收率均在 97 9%~ 10 1 8%。 相似文献
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1000.
区间牛顿法具有较强的全局收敛性。在实际应用过程中,只要给出非线性方程组中所有自变量的变化范围,区间牛顿法就能在数学上保证找到非线性方程组的所有解。因此,广泛应用于化工过程计算与优化中。 相似文献