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排序方式: 共有505条查询结果,搜索用时 14 毫秒
1.
Hanan. M. Eyssa Mona Y. Elnaggar Magdy M. Zaky 《Polymer Engineering and Science》2021,61(11):2843-2860
Seals prepared from acrylonitrile–butadiene rubber (NBR) are primarily used in nuclear services. Nevertheless, at relatively high ionizing radiation doses, NBR seal materials may undergo radiation-induced degradation processes, leading to adverse effects on the sealing ability life. Herein, to strengthen the functional characteristics of NBR seals against radiation, graphene oxide (GO) nanoparticles were prepared and characterized by transmission electron microscopy, X-ray diffraction (XRD), Fourier transform infrared (FTIR), and ultraviolet/visible spectroscopies. Various NBR/GO composites fabricated with different ratios of GO nanoparticles and in the presence or absence of carbon black (CB) were investigated via cross-linking density, scanning electron microscopy, XRD, FTIR, and mechanical and thermal stability analyses. The synergistic effect of the simultaneous presence of GO and CB on the NBR seal sensitization to gamma radiation up to a dose of 1 MGy was studied. The physicomechanical properties were enhanced by adding GO nanosheets up to 3 phr and by incorporating 35 phr of a CB with GO until 5 phr. Further, the application of γ-irradiation resulted in an overall enhancement in the mechanical, physical, and thermal stability of the prepared composites up to 0.5 and 1 MGy with GO nanosheets in the absence or presence of CB particles, respectively. The mechanical measurements indicated significant increments by loading with GO nanosheets in the absence and presence of CB as well as by irradiation. The tensile strength elevated up to about 121%, 336%, and 366% by adding 3 phr GO, 3 GO:35 CB phr, and 5 GO:35 CB phr, respectively. 相似文献
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回顾了我国印染助剂,特别是表面活性剂的发展状况。重点介绍了前处理助剂的革新和Gemini表面活性剂及树状聚合物的合成方法、性能及应用。提出行业应注重创新,以促进我国印染助剂发展。 相似文献
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Abstract The combination of levulinic acid and sodium dodecyl sulfate (SDS) in recent years has shown considerable promise as an antimicrobial intervention. Both ingredients have been designated by the U.S. Food and Drug Administration (FDA) as Generally Recognized as Safe (GRAS) for being used as a flavoring agent and multipurpose food additive, respectively. The use of levulinic acid and SDS alone has limited antimicrobial efficacy on tested microorganisms, and synergism between levulinic acid and SDS has been observed. The postulated mechanism of action of the synergistic effect is presented. The antimicrobial efficacy of levulinic acid plus SDS remains high even when organic materials are present. The other features, including penetration, foamability, and being readily soluble, extend its potential applications to disinfection of difficult-to-access areas and control of foodborne pathogens both in a planktonic state and in a biofilm. These features indicate that the levulinic acid plus SDS combination may have the potential to be applied within the food processing environment on a large scale. 相似文献
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为最大化虚拟企业项目中各任务间的协同程度,提出了一种基于协同学理论的虚拟企业伙伴选择方法。建立了以极大化系统协同度为优化目标的伙伴选择模型,该模型考虑了系统的交货时间、总费用和产品准时交货率等因素的协同度。此外,针对基本杂草算法在求解伙伴选择模型的过程中容易陷入局部极值的缺点,设计了一种嵌入混沌搜索行为的混合杂草算法来求解该模型。仿真结果表明了该方法的可行性及有效性。 相似文献
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温室盆栽法测定除草活性试验结果表明,380g/L噁草酮悬浮剂及其不同桶混助剂配伍对水稻稗草有较好的除草活性,特别是加入桶混助剂GY—Hba S2#的380g/L噁草酮悬浮剂在试验中产生较显著的增效作用。 相似文献
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超声波与微酸性电解水在食品杀菌保鲜中的应用研究进展 总被引:1,自引:0,他引:1
民以食为天,治理“餐桌污染”和确保人民群众“舌尖上的安全”是党和国家管控食品安全和保障民生的重要举措之一。食品中微生物的生长会导致食品品质劣变, 造成食品货架期缩短, 从而引发食品安全这一备受大众关注的社会问题。超声波作为一种非热加工技术, 可以使一些微生物失活, 被认为是食品工业中传统杀菌保鲜技术的潜在替代方法。微酸性电解水是近几十年食品工业中最有前途的杀菌剂之一, 具有很强的广谱杀菌效果。超声波与微酸性电解水协同处理能够发挥“1+1>2”的杀菌效果, 在食品杀菌保鲜中具有巨大的应用潜力。本文综述了超声波、微酸性电解水单独作用和协同处理的杀菌机制、对微生物生长的影响及在食品杀菌保鲜中应用的研究进展, 并展望未来的发展趋势, 以期为其在食品加工与安全领域的研究与应用提供参考。 相似文献
9.
Nain Tara Mazhar Iqbal Qaisar Mahmood Khan Muhammad Afzal 《Water and Environment Journal》2019,33(1):124-134
This pilot study evaluated the effects of bacterial augmentation on the efficiency of floating treatment wetlands (FTWs) to remediate textile wastewater. Two wetland plants, Phragmites australis and Typha domingensis, were used to develop FTWs, which were then augmented with a bacterial consortium of three strains (Acinetobacter junii, Pseudomonas indoloxydans, and Rhodococcus sp.). Results showed that both plant species removed colour, organic matter, toxicity, and heavy metals from textile wastewater and their removal efficiency was further enhanced by augmentation with bacteria. The maximum removal efficiencies of colour, COD and BOD after an 8‐day period were 97, 87 and 92%, respectively, by FTWs carrying P. australis inoculated with the bacterial consortium. Furthermore, the same combination showed 87–99% reduction of heavy metals in the textile wastewater as well. These results indicate that FTWs can be used for the treatment of textile effluent and their working efficiency can be improved by plant‐bacterial synergism. 相似文献
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