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91.
92.
数据一致性是主备用系统必须解决的问题.目前主备系统的一致性都采用手工编程来实现,导致代码结构繁杂,且效率不高.利用VxWorks的异常处理机制,结合RISC CPU的特性,设计实现了一个数据一致性功能组件.这个组件可使数据的一致性处理自动化. 相似文献
93.
Sumin Wang Yaru Fan Qiguan Wang Lei Yang Jiayin Shang Shenbao Qiu Wenzhi Zhang 《Journal of Materials Science》2018,53(15):10835-10845
In this paper, multiple hydrogen bonding interaction of ureidopyrimidinone (UPM) was employed as the linking bridge for the formation of a novel porphyrin·multi-walled carbon nanotube (MWNT) hybrid, which was then used to fabricate a layer-by-layer (LbL) film composed of porphyrin-UPM·MWNT-UPM. Both in the assembled hybrid and the LbL film, porphyrin was closely attached to the surface of the MWNT under the strong multiple hydrogen bonding interaction, forming the core–shell structure. In addition, strong electronic communication was observed between porphyrin and MWNT. The hydrogen bonding association behavior between porphyrin-UPM and MWNT-UPM was attentively analyzed by UV–Vis spectra, fluorescent spectra and transmission electron microscope experiments. It was found that the hydrogen bonding interactions were crucial for the formation of the supramolecular hybrid and the LbL film as well as the occurrence of interfacial electronic communication. This result indicated that the introduction of strong noncovalent bonding interaction between donor and acceptor is an appropriate way to control the material structure and facilitate the interfacial electronic communication in the hybrids which lay the groundwork for their application in electrochemical sensors or photovoltaic devices. 相似文献
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Linyuan Shang 《工程优选》2016,48(6):1060-1079
This article investigates topology optimization of a bi-material model for acoustic–structural coupled systems. The design variables are volume fractions of inclusion material in a bi-material model constructed by the microstructure-based design domain method (MDDM). The design objective is the minimization of sound pressure level (SPL) in an interior acoustic medium. Sensitivities of SPL with respect to topological design variables are derived concretely by the adjoint method. A relaxed form of optimality criteria (OC) is developed for solving the acoustic–structural coupled optimization problem to find the optimum bi-material distribution. Based on OC and the adjoint method, a topology optimization method to deal with large calculations in acoustic–structural coupled problems is proposed. Numerical examples are given to illustrate the applications of topology optimization for a bi-material plate under a low single-frequency excitation and an aerospace structure under a low frequency-band excitation, and to prove the efficiency of the adjoint method and the relaxed form of OC. 相似文献
96.
Nitrogen‐Doped Porous Carbon Nanosheets Templated from g‐C3N4 as Metal‐Free Electrocatalysts for Efficient Oxygen Reduction Reaction 下载免费PDF全文
97.
FLAIR气测系统及其在渤海湾盆地低电阻率油气层的应用 总被引:2,自引:2,他引:0
低电阻率油气层由于电阻率偏低和多种复杂因素的影响,常规测井手段难以识别,而借助气测录井手段进行解释评价具有优势.围绕低电阻率油气层气测录井解释,较系统介绍了FLAIR气测录井系统的硬件组成及解释评价软件(INFACT)的解释评价方法.应用该系统进行解释评价时,首先对解释井段进行质量评估,而后进行流体相分析、甲烷气体含量(甲烷校正值)计算及评价,结合常规烃类气体比率法组合特征分析,初步评价储集层流体类型,最后参考其他录井资料进行综合解释,确定油气水层.该系统在渤海湾盆地H 35井两井段的应用实例以及其他4口井9层低电阻率油气层应用统计资料表明,经试油验证其总体解释符合率为87.5%. 相似文献
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99.
Jin Shu Mao Xiang Hui Wang Kang De Yao Qing Xin Shang Guang Hui Yang 《Journal of Materials Science》2003,38(10):2283-2290
The culture of keratinocytes on flexible membranes has been proposed as a means to simplify, accelerate and improve the efficiency with which proliferating cells are delivered to full thickness or non-healing skin defects. The purpose of this article was to study the ability of chitosan-gelatin manbranes to facilitate the growth of human keratinocytes. The membranes with different chitosan contents were studied. The surface properties of chitosan-gelatin membranes were investigate by SEM, and water contact angle test. The mechanical property of the membranes was tested. Data implied that gelatin could make the membranes more flexible and hydrophilic than chitosan membranes, which may regulate the seeded cells behavior. Loading human keratinocytes on chitosan-gelatin membranes, cells attachment, spread, and growth were investigated by light microscopy, SEM, and MTT test. The results suggested that the adhesion and proliferation of keratinocytes seeded on chitosan-gelatin membranes were same as on tissue culture plate, in which gelatin could modify the interaction between keratinocytes and chitosan membranes. Therefore, chitosan-gelatin membrane is a good candidate for keratinocytes delivery system. 相似文献
100.
包装图形设计在包装商品中的作用 总被引:2,自引:0,他引:2
从事商品包装设计的设计师们都知道,包装设计具有双重性,即艺术性与商品性。而从销售包装设计的角度来看艺术性是隶属于商品性的,两者的融合才是一件完美的销售包装设计。包装设计表达语言与及其它方面设计相比具有一定的共性,也存在着一定差异。它是一种视觉传达设计,由于文化传达的方式,内容和媒体的不同,因而有其表达特点。 相似文献