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121.
H. Djidjelli A. Boukerrou A. Rabouhi R. Founas M. Kaci O. Zefouni N. Djillali L. Belmouhoub 《应用聚合物科学杂志》2008,107(3):1459-1465
The changes in mechanical properties, the thermal stability, and the water absorption capacity of poly (vinyl chloride)/olive residue flour composites were studied as a function of various residue olive flour ratios, i.e., 0, 5, 15, and 25% by weight taking into account the effect of benzylation chemical treatment of the filler. The study showed that composite samples prepared with the untreated filler exhibited higher tensile modulus and hardness compared with the neat resin, whereas elongation and tensile strength were observed to decline. On the other hand, the PVC hardness was found to increase with addition of the untreated olive residue flour (ORF), however the composite samples prepared with the benzylated flour exhibited lower hardness than those prepared with untreated olive residue. Moreover, the amount of absorbed water depends on the amount of filler in the composite. The comparison of the results obtained from the samples of F5, F20, and F30 formulations between the untreated and treated ORF indicated a reduction in absorbed water for the composite samples containing treated ORF with benzyl chloride. As a result, the mechanical properties of the treated composites were improved. Furthermore, the thermal characterization of the different samples carried out by color change test and thermogravimetric analysis revealed an increase in the onset temperatures of decomposition for the treated composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
122.
Effect of Li+ ions on structure,properties, and actuation of cellulose electro‐active paper actuator
We have reported an electro‐active paper actuator from regenerated cellulose. After dissolving cellulose fibers with a solution of lithium chloride in N,N‐dimethylacetamide, cellulose was regenerated by combining distillation of cellulose solution along with washing with the mixture of deionized water, isopropyl alcohol, and running water. However, the effect of Li+ ions on structure, properties, and the actuation behavior of the actuator was not studied. This article describes the changes in these parameters when the Li+ ions are removed by subjecting it to different running water exposure time. The structure and properties of cellulose electro‐active paper and its actuation behavior were studied. As Li+ ions content reduced from 4354.17 to 10.26 ppm by increasing the exposure time of running water, crystallinity, Young's modulus, and bending displacement decreased. Details about the investigation have been explained. This elimination of ions is important to increase the piezoelectric effect in EAPap by decreasing the ion migration effect. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008 相似文献
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论薄板坯连铸连轧产品质量优势 总被引:1,自引:0,他引:1
廖喆 《金属材料与冶金工程》2003,31(4):7-10
通过对薄板坯连铸连轧工艺的分析,深入研究了其产品的质量优势,同时还指出了在产品生产过程中需要重点注意解决的一些问题。 相似文献
126.
详细介绍了ZPG系列盘式真空过滤机的主要特点、基本原理和主要技术参数。对盘式真空过滤机的过滤理论进行了系统的研究 ,以及为提高过滤系数和降低滤饼水分所采取的关键措施。与传统的真空过滤机进行了对比 ,表明ZPG系列盘式真空过滤机的滤饼水分可以降低 1 %~ 3 % ,过滤系数提高 3 0 %~5 0 % ,过滤每吨精矿的能耗可以降低 5 0 %左右 ,使得ZPG系列盘式真空过滤机在国内各大冶金矿山得到全面推广使用 ,创造了巨大的经济效益和社会效益。 相似文献
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Psychologists are often asked to testify in court. However, concerns have been expressed in both the legal and psychological literatures about the quality of these services. This article presents survey results comparing the practice patterns of generally licensed psychologists with those of specialist forensic diplomates in providing risk evaluations. Results suggest that general clinicians frequently perform these evaluations, but forensic diplomates use more modern risk instruments, are more aware of the scientific literature, and provide the court with more information about the scientific basis of their testimony. The implication of these results for legal professionals, psychologist training, and practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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虚拟企业模型并行仿真研究 总被引:4,自引:0,他引:4
随着各种全新的制造理念,特别是虚拟企业的出现,企业模型的规模不断扩大,使目前存在的大多数企业模型仿真系统的效率大大下降。该文针对此问题,通过深入分析虚拟企业模型结构,并在已有的构件化企业建模体系CEMS及其仿真系统的基础上,结合异步仿真技术和多线程技术提出了一种分层式企业模型仿真体系结构,为虚拟企业模型的快速高效的仿真提供了一种有效的方法。 相似文献
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