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971.
在CTAB/正己烷/正丁醇/水(W/O)四元反相微乳液体系中原位聚合制备了铜掺杂氧化锌/聚吡咯(CZ/PPy)纳米复合物.用X射线衍射仪、扫描电子显微镜、透射电子显微镜、红外光谱仪和紫外-可见光谱仪分别表征了样品的结构、形貌和光谱学性能;以大肠杆菌(Escherichia coli)、金黄色葡萄球菌(Staphylococcus aureus)和白色念珠菌(Candida albicans)为测试菌株研究了样品的抗菌活性.结果表明PPy包覆在CZ粒子表面形成了核-壳结构的CZ/PPy复合物,PPy链与CZ纳米粒子之间存在一定的相互作用;复合物的抗菌性能优于CZ,且抗菌活性随着CZ含量的增加而增大. 相似文献
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《Soft Materials》2013,11(3):393-408
The goal of this research is to develop a composite hydrogel system for sustained release of therapeutic agents. The hydrogel composites were prepared by embedding drug‐loaded, biodegradable poly (DL‐lactide‐co‐glycolide) (PLGA) microparticles in semicrystalline hydrogels of polyvinyl alcohol (PVA). The gels were physically cross‐linked by the formation of the crystallites. The presence of the crystallites and the composite nature of the structure were confirmed by using differential scanning calorimetry and ATR‐FTIR spectroscopy. The distribution of microparticles in the hydrogel matrix was evaluated by using confocal laser scanning microscopy with coumarin‐6 as a fluorescence marker. The numbers of particles in the hydrogel matrix increased along the scanning depth, indicating uneven distribution. The release behavior of a model therapeutic agent, hydrocortisone, was evaluated, and the hydrogel composite system provided for better control of release than the microparticles and hydrogels alone. The addition of outer layers of PVA to the original single‐layer composite further reduced the initial burst effect from the microparticles and allowed for a linear release profile for greater than 1 month. 相似文献
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This work concerns notched composite plates repaired with external circular patches. Their load carrying capability and failure process under tensile loading were investigated experimentally. In the case of a strong adhesive joint, the stiffness of the patches has to be optimized to release high stress concentration and obtain the best repair performance. It was found that the damage progression of the repairs depends not only on the patch stiffness but also on the stacking sequence. With visual inspection and acoustic emission, three modes of damage and failure process for patch repaired specimens were identified. Theses damage models are essential for the development of a numerical design tool for the optimization of external patch repairs. 相似文献
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Jingkun Xu Baoyang Lu Haijun Song Hui Shi Yuanyuan Yao Long Zhang 《Journal of Polymer Science.Polymer Physics》2014,52(11):737-742
A novel strategy via paper as an effective substrate has been introduced as a thermoelectric material in this work. Free‐standing poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/paper composite films are conveniently prepared by a one‐step method of directly writing PEDOT:PSS solution on paper, making the process simple, rapid, and facile. The free‐standing composite films display excellent flexibility, light weight, soaking stability in water, and great potential in large‐scale production. Improved thermoelectric properties are obtained in PEDOT:PSS/paper composite films, owing to the simultaneously enhanced Seebeck coefficient (30.6 μV K?1) and electrical conductivity, and a low thermal conductivity (0.16 W m?1 K?1) compared with pristine PEDOT:PSS films. The results indicate that paper as an effective substrate is suitable for the preparation of high‐performance and flexible thermoelectric materials. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 737–742 相似文献
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