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951.
952.
用磁控溅射离子镀在试件上先镀一层铝镀层,再真空气相化学沉积一层Parylene(聚对二甲苯)聚合物,与在试件上先真空气相化学沉积一层Parylene聚合物,再磁控溅射离子镀一层铝镀层,两种方法制备出铝加Pary—lene和Parylene加铝的两种复合涂层。本文对这两种复合涂层划痕、磨损实验进行了研究,并运用EDX、SEM形貌等方法进行了复合涂层特性对比分析。得出铝加Parylen和Parylen加铝复合涂层都有低的透湿性,但前种复合涂层较后种复合涂层有较强的防腐、耐磨性和自润滑性能。 相似文献
953.
随着高分子材料阻燃技术的发展,新型无卤环保型阻燃剂和阻燃技术的应用研究日益受到关注,如纳米型阻燃剂、膨胀型阻燃剂、磷系阻燃剂、超细氢氧化镁阻燃剂等.就超细氢氧化镁阻燃剂的制作与阻燃性能做出研究. 相似文献
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龙宇羊依金李春涛郭祖田谭显东信欣刘盛余 《四川化工》2014,(1):4-8
采用化学活化法,以污水处理厂的剩余污泥为原料,掺杂软锰矿作为造孔剂制备新型污泥吸附材料。研究新型污泥吸附材料对废水中Cd(Ⅱ)、Cr(Ⅲ)的吸附行为。结果表明:新型污泥吸附材料的比表面积比纯污泥吸附材料提高了52.3%。新型吸附材料对Cd(Ⅱ)、Cr(Ⅲ)的吸附容量和吸附能力大小:Cr(Ⅲ)Cd(Ⅱ)。两种金属离子的吸附性能符合二级吸附速率方程,吸附速率:Cd(Ⅱ)Cr(Ⅲ),平衡吸附量:Cd(Ⅱ)Cr(Ⅲ)。对于Cd(Ⅱ),颗粒内扩散过程是该吸附速率的控制步骤,而对于Cr(Ⅲ),颗粒内扩散过程不是吸附速率的控制步骤。 相似文献
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A novel method dispersing nickel in fine particles on activated carbon (AC) was proposed in this study. The nickel particles with 2.2 nm average diameter supported on AC were obtained through re-dispersing the nickel particles by treating with methyl iodide under atmospheric pressure. High dispersion of nickel particles promoted the activity for methanol vapor-phase carbonylation over Ni/AC catalyst. 相似文献
Graphical Abstract
959.
Isothermal melt crystallization and performance evaluation of polylactide/thermoplastic polyester blends with multi‐functional epoxy
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Xueli Lu Qiaoqiang Lv Xiulong Huang Zijian Song Nai Xu Sujuan Pang Lisha Pan Tan Li 《应用聚合物科学杂志》2018,135(23)
A multi‐functional epoxy (ADR) was used to improve compatibilization of poly(lactic acid) (PLA)/ thermoplastic polyester elastomer (TPEE) blends. Influence of ADR on isothermal melt crystallization of the blends was investigated. The results show that isothermal melt crystallization rate of the samples increases with ADR loading. It can be attributed to a nucleation enhancement resulted from an increase of molecular weight and melt viscosity created by the chain extension/branched process of PLA in the presence of ADR. In addition, the maximum crystallinity of the samples shows a decrease with increasing ADR loading because of the chain extended and branched reaction. Quenched and crystallized samples were fabricated using compression molding under different cooling conditions in‐mold. Effects of crystallinity and ADR on mechanical performances of the PLA/TPEE sample were investigated. With increasing the crystallinity, the PLA/TPEE sample shows a marked enhancement in heat resistance. However, the tensile ductility of the crystallized PLA/TPEE sample drastically decreases due to the formation of firm crystal crosslinking and the incompatibility between PLA and TPEE. It is notable that the tensile ductility of the crystallized samples is improved with the introduction of ADR owing to its reactive compatibilization effect. Finally, the crystallized PLA/TPEE/ADR samples with improved heat resistance and relative higher ductility are obtained. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46343. 相似文献
960.
Counterion effects of nickel and sodium dodecylbenzene sulfonate adsorption to multiwalled carbon nanotubes in aqueous solution 总被引:3,自引:0,他引:3
Batch experiments were conducted to elucidate the adsorption of a widely used anionic surfactant (sodium dodecylbenzene sulfonate (SDBS)) and nickel on multiwalled carbon nanotubes (MWCNTs). Counterion effect on the removal of SDBS and nickel by using MWCNTs was also studied. The microscopic changes of MWCNTs before and after nickel and SDBS adsorption were characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). X-ray photoelectron spectroscopy (XPS) was performed to study the adsorption mechanism of nickel at a molecular level. The spectroscopic analysis indicated that the adsorption mechanism was mainly attributed to chemical interaction between nickel and the surface functional groups of MWCNTs and surface adsorbed SDBS. The adsorbed SDBS on MWCNTs could lead to the modification of the MWCNT surfaces and partial complexation of nickel with SDBS adsorbed on MWCNTs. MWCNTs are efficient material in the removal of SDBS and nickel from large volume of wastewater. 相似文献