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1.
Journal of Chemical Ecology - The cotton bollworm, Helicoverpa armigera, is one of the most destructive agricultural pests in the world, infesting cotton, maize, soybean, and many other crops. In... 相似文献
2.
针对南京市某生活垃圾焚烧发电厂循环冷却水硬度高、循环管道及冷却塔材料表面结垢严重的问题,开展循环冷却水的硬度控制小试试验,并进行生产化试验.采用加药絮凝沉淀法考察了Ca(OH)2、NaOH、阻垢剂、阳离子聚丙烯酰胺(CPAM)等药剂对循环冷却水硬度试验的影响.结果 表明:与只添加Ca(OH)2或共同添加Ca(OH)2、阻垢剂相比,将Ca(OH)2替换为NaOH后,循环水硬度去除率得到了显著的提高;与只投加NaOH相比,组合投加NaOH和阻垢剂时,废水硬度由800.8mg/L降至260.26 mg/L,去除率达67.5%.通过在南京某垃圾焚烧发电厂进行生产化试验后,试验结果表明,通过合理调节NaOH和阻垢剂用量,可以很好地实现现场循环水硬度去除率为50%的目标. 相似文献
3.
采用动态硫化法制备了高密度聚乙烯(HDPE)/丁苯橡胶(SBR)热塑性硫化胶(TPV),研究了橡塑比、定型温度、回复温度及增容剂苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)对HDPE/SBR TPV形状记忆性能的影响,观察了其微观结构,提出了形状记忆行为机制。结果表明,HDPE/SBR TPV具有典型的"海-岛"结构,拉伸后其表面存在明显的取向结构;SBS能显著提高HDPE/SBR TPV的形状记忆性能,当SBS用量为6份、定型温度和回复温度均为120℃时,HDPE/SBR TPV的形状记忆性能最佳。 相似文献
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5.
通过对养老护理员队伍稳定性的调查研究,了解长护险制度对于养老机构护理员队伍离职意愿的影响,为提高护理员队伍稳定性、促进队伍良性发展提供长护险政策优化对策和建议。采用定性和定量相结合的调查研究办法,对上海养老机构和居家养老护理员进行问卷调查和个别访谈,采用SPSS23.0软件统计分析调查资料。结果显示,在长护险制度背景下养老机构护理员压力趋多、负担趋重、薪酬公平感降低,队伍稳定性受到极大影响,建议通过缩小养老机构和居家养老护理员之间的薪酬差距,建立居家养老护理员实地培训基地,注重护理员队伍的培育和素质提升问题,优化护理员考核评价标准等一系列措施,优化长期护理保险政策。 相似文献
6.
C. BOULOGNE C. GILLET L. HUGHES R. LE BARS A. CANETTE C.R. HAWES B. SATIAT-JEUNEMAITRE 《Journal of microscopy》2020,280(2):86-103
Up-to-date imaging approaches were used to address the spatiotemporal organisation of the endomembrane system in secretory cells of Dionaea muscipula. Different ‘slice and view’ methodologies were performed on resin-embedded samples to finally achieve a 3D reconstruction of the cell architecture, using ultrastructural tomography, array tomography, serial block face-scanning electron microscopy (SBF-SEM), correlation, and volume rendering at the light microscopy level. Observations of cryo-fixed samples by high-pressure freezing revealed changes of the endomembrane system that occur after trap activation and prey digestion. They provide evidence for an original strategy that adapts the secretory machinery to a specific and unique case of stimulated exocytosis in plant cells. A first secretion peak is part of a rapid response to deliver digestive fluids to the cell surface, which delivers the needed stock of digestive materials ‘on site’. The second peak of activity could then be associated with the reconstruction of the Golgi apparatus (GA), endoplasmic reticulum (ER) and vacuolar machinery, in order to prepare for a subsequent round of prey capture. Tubular continuum between ER and Golgi stacks observed on ZIO-impregnated tissues may correspond to an efficient transfer mechanism for lipids and/or proteins, especially for use in rapidly resetting the molecular GA machinery. The occurrence of one vacuolar continuum may permit continuous adjustment of cell homeostasy. The subcellular features of the secretory cells of Dionaea muscipula outline key innovations in the organisation of plant cell compartmentalisation that are used to cope with specific cell needs such as the full use of the GA as a protein factory, and the ability to create protein reservoirs in the periplasmic space. Shape-derived forces of the pleiomorphic vacuole may act as signals to accompany the sorting and entering flows of the cell. 相似文献
7.
使用气-质联用仪测定餐饮废油生物柴油(WCME)和-10号柴油(-10PD)的组成,使用冷滤点试验器和运动黏度试验器测定WCME的低温流动性,同时使用调合、添加低温流动性改进剂的方法改进WCME的低温流动性。实验结果表明,WCME主要由饱和脂肪酸甲酯和不饱和脂肪酸甲酯组成,质量分数分别为27.63%和71.81%;WCME冷滤点为0℃,运动黏度(40℃)为4.41mm2/s;WCME与-10PD调合后,冷滤点降低,其中B20的冷滤点最低,为-13℃,运动黏度随着WCME的体积分数的减少,逐渐接近-10PD的运动黏度。通过添加低温流动性改进剂,WCME,B10,B20的冷滤点分别从0,-8,-13℃降至-4,-26,-25℃。 相似文献
8.
目的阻碍热镀锌板出现白锈,提高镀锌层的耐腐蚀性能。方法采用正交试验法优化出添加虫胶水溶液的有机无机复合钝化液。通过电化学Tafel极化曲线、交流阻抗(EIS)、乙酸铅点滴和中性盐雾试验,对比分析基体、硅酸盐+虫胶复合钝化膜与铬酸盐钝化膜的耐腐蚀性能。采用摩擦法测试对比分析基体和无铬钝化膜试样的附着性能,并通过扫描电子显微镜、X射线光电子能谱和红外光谱对形貌和结构进行分析。结果添加虫胶水溶液的复合钝化膜表面平整致密,72 h中性盐雾试验后的腐蚀面积小于10%。乙酸铅点滴试验和电化学测试显示,复合钝化膜的耐腐蚀性能较基体好。附着力试验测试显示,复合钝化膜具有良好的附着能力。结论因为复合钝化液中的虫胶与硅酸盐交织为O—Si—CH_2结构,与金属离子结合生成致密的膜层附着在镀锌层表面,使得复合钝化膜致密平整,且使腐蚀过程得到了强烈的抑制。 相似文献
9.
Yuhao Huang Akhil Garg Saeed Asghari Xiongbin Peng My Loan Phung LE 《International Journal of Hydrogen Energy》2018,43(1):341-353
Energy production systems such as proton-exchange membrane fuel cell (PEMFC) has a promising future in the cleaner energy market due to zero emissions. Rubber pad forming (RPF) process of metallic bipolar plates of PEMFCs is gaining attention among the researchers. Studies based on design of experiments have been conducted to find the crucial parameters of the forming process. These methods are based on the assumptions of the model structure, correlated residuals, etc., which can cause uncertainty in estimation ability of the model on unseen data. Therefore, the present study focuses on the design of robust models of these parameters for PEMFCs using an optimization approach of genetic programming (GP). The inputs from the experiments considered in GP are radius, the friction coefficient, the filling factor and the minimum thickness. Experiments on PEMFCs validates the performance of the GP models. Further, the relationships between the two inputs and the three outputs for PEMFCs are generated as well as the contributions of each input to each of the output. Optimization of the models generated by GP can further determine the forming quality of metallic bipolar plates of PEMFCs by an appropriate setting of the two inputs. 相似文献
10.
Experimental and optimization of material synthesis process parameters for improving capacity of lithium‐ion battery 下载免费PDF全文
Yuhao Huang Binh Thanh Tran Saeed Asghari Hoang‐do Nguyen Xiongbin Peng Akhil Garg My Loan Phung LE 《国际能源研究杂志》2018,42(10):3400-3409
New methods for synthesis of active materials have been developed to improve capacity and cycle life performance of lithium‐ion batteries. Past studies have focused on routes of development of materials and new processes, which might not be economical for large‐scale production. In this regard, this study examines a widely employed carbothermal reduction technology for the synthesis of lithium‐iron phosphate (LiFePO4/C) and investigates effects of process conditions during this synthesis on final battery performance. An experimental combined genetic programming approach is used to model the effects of crucial process conditions (sintering time, the carbon content, and the sintering temperature) on the discharge capacity of the assembled battery. Experiments are conducted to collect the discharge capacity data based on varying LiFePO4/C synthesis conditions, and genetic programming is employed to develop a suitable functional relationship between them. The results show that the battery discharge capacity is controlled significantly by adjusting sintering temperature and carbon content, while the effect of sintering time is found to be insignificant. Further, the interaction effect of the sintering time and carbon content is much more obvious than that of the sintering time and the sintering temperature. The findings from the study pave the way for the optimum design of the synthesis process of LiFePO4/C for a higher battery performance. 相似文献