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排序方式: 共有721条查询结果,搜索用时 281 毫秒
1.
Zhang Qi Wang Yujing Zhang Xueling Song Jun Li Yinlei Wu Xuehong Yuan Kunjie 《Journal of Materials Science》2022,57(14):7208-7224
Journal of Materials Science - Form-stable composite phase change materials (C-PCMs) prepared by microencapsulation method and porous matrix adsorption method need for compression molding after... 相似文献
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A hollow-fiber-supported stable Au/FAU catalytic membrane was successfully synthesized through a polydopamine coating modification-removal strategy and used as a flow-through catalytic membrane reactor for preferential oxidation of CO. Small Au nanoparticles can be efficiently isolated by dopamine and the dopamine-derived carbon shells. The interactions between Au nanoparticles and zeolite layer support are enhanced during annealing at high temperature under an inert atmosphere. A zeolite membrane supported Au nanoparticle catalyst was obtained after the removal of carbon shells, which showed high catalytic activity and stability for the removal of CO from hydrogen. 相似文献
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该文利用滑动式Lagrange插值算法,从三个方面对BDS三种星历进行了内插精度分析,并与传统La-grange插值算法做了比较.首先对比相同阶数下两种算法的非端点处插值结果的精度;其次考虑端点龙格现象,分析两种方法的端点插值结果的精度;最后根据计算结果的均方根误差,分析插值结果整体精度的大小,并采用BDS精密星历数据进行验证.研究结果表明,滑动式Lagrange插值算法的插值精度较高,且误差分布均匀,最高可达亚毫米级别.该方法较好地适用于BDS星历的内插. 相似文献
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通过五参数法,测定了一种塑性变形条件下硬质合金结构中的两类重位点阵晶界,即Σ13a晶界和Σ2晶界,的晶界特征分布。通过与未经过塑性变形的试样进行对比,发现两类重位点阵晶界的数量以及相应惯习面的赋存频率,在塑性变形条件下都有所降低。通过对硬质合金试样结构中的晶界面类型进行精确区分,塑性变形条件下晶界特征分布的演进过程得到解释。 相似文献
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N‐halamine‐modified polyglycolide (PGA) multifilament as a potential bactericidal surgical suture: In vitro study 下载免费PDF全文
In this study, new cationic homopolymer and anionic copolymer were synthesized, and deposited onto polyglycolide sutures using a layer‐by‐layer assembly technique. The coated sutures were rendered antibacterial by chlorinating with dilute solution of household bleach solution at pH 7. The chlorination treatment transformed the N? H groups of anionic copolymer into N‐halamine structures. The N‐halamine‐modified sutures were challenged with Staphylococcus aureus and Escherichia coli O157:H7 bacteria at different contact times. The suture with chlorine loading of 0.22% completely inactivated both bacterial strains in 30 min contact time. Fourier transform infrared spectroscopy, scanning electron microscopy, and analytical titration confirmed the successful deposition of the N‐halamine multilayers. The effect of layer‐by‐layer coatings of polyelectrolytes on the chlorine loading and antibacterial efficacy of sutures was evaluated. The straight‐pull and knot‐pull strength tests performed on the sutures reported slight decline in tensile properties after chlorination treatment. The in vitro hemolysis and cytocompatibility tests revealed that the N‐halamines‐based antibacterial sutures were biocompatible. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42483. 相似文献
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Improving the hydrophobicity of nylon fabric by consecutive treatment with poly(acrylic acid), tetraethylorthosilicate,and octadecylamine 下载免费PDF全文
Nylon fabric was consecutively treated with poly(acrylic acid) (PAA), tetraethylorthosilicate (TEOS), and octadecylamine (OA) to improve its hydrophobicity. We proposed that PAA could be used as a mediator between nylon and OA to provide a high density of the carboxyl moiety. TEOS was used to increase the surface roughness of the nylon fabric by hydrolysis and condensation, and OA was used to reduce the surface energy of the nylon fabric with its long alkyl chains. Both the increase in the surface roughness and the reduction in the surface energy contributed to the improvement of the hydrophobicity of the nylon fabric. The hydrophobicity of the treated nylon fabric was evaluated by the measurement of the water contact angle, water resistance to spray, and hydrostatic pressure. Scanning electron microscopy images showed that the surface roughness of the nylon fabric was significantly increased by treatment with TEOS. The nylon fabric with the PAA/TEOS/OA consecutive treatment exhibited a water contact angle of 125°, a resistance to water spray of 90, and a hydrostatic pressure of 275 mm. It was interesting to find that the PAA/TEOS/OA consecutive treatment slightly enhanced the wrinkle recovery but had no apparent effects on the degree of whiteness and the breaking strength of the nylon fabric. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42456. 相似文献