排序方式: 共有149条查询结果,搜索用时 0 毫秒
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为实现光催化制氢,通过模板剂水热合成和浸渍还原法制备出Ag负载ZnS光催化剂.利用XRD、SEM和UV-vis对样品进行结构和光学性质表征,利用光催化分解Na2S+Na2SO3溶液制氢评价光催化性能.结果表明:在酸性条件下,模板剂质量浓度较低而硫源和锌源较多时,样品为棒状,主要以立方闪锌矿结构存在;反之,样品主要为球状... 相似文献
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Training neural network to recognize targets needs a lot of samples.People usually get these samples in a non-systematic way,which can miss or overemphasize some target information.To improve this situation,a new method based on virtual model and invariant moments was proposed to generate training samples.The method was composed of the following steps:use computer and simulation software to build target object’s virtual model and then simulate the environment,light condition,camera parameter,etc.;rotate the model by spin and nutation of inclination to get the image sequence by virtual camera;preprocess each image and transfer them into binary image;calculate the invariant moments for each image and get a vectors’ sequence.The vectors’ sequence which was proved to be complete became the training samples together with the target outputs.The simulated results showed that the proposed method could be used to recognize the real targets and improve the accuracy of target recognition effectively when the sampling interval was short enough and the circumstance simulation was close enough. 相似文献
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低分子量壳聚糖作为非病毒性基因治疗载体有着广阔的前景,已成为研究的热点。综述了低分子量壳聚糖的制备方法以及载基因的研究进展,并讨论了影响转染的因素。 相似文献
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正为服务于当前国家新能源发展战略的需要,国网长沙供电公司(下称"长沙公司")以绿色发展理念和标准化管理理论为指导,以"诚信、责任、创新、奉献"的核心价值观和坚定实施国家电网公司"两个替代"为宗旨,通过对长沙分布式电源并网服务项目进行任务分解,建立了一套科学完备、易复制、可评估的分布式电源并网服务方法体系。该方法体系符合当下国家大力推广新能源的趋势,顺应了电力体制改革要求,有效地充盈和提升 相似文献
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普光气田礁滩相储层具有溶蚀孔洞发育、局部裂缝发育、储层孔隙结构比较复杂、非均质性比较强的特点。储层孔隙结构复杂导致了储层分类难度大、精度低等难题。进入开发阶段,前期较粗的地质认识已不能满足开发需要,需要及时跟踪分析和掌握气井生产动态特征,研究不同类型储层的展布特征,评价储层连通状况,为指导气田正常生产管理及调控气井合理产量提供依据。以岩心观察、气井生产动态为基础,结合岩心压汞、铸体薄片分析等资料,利用常规测井资料研究形成了一套针对普光气田礁滩相储层的分类评价方法,即采用渗流特征参数结合比采气指数对储层进行分类评价。该评价结果与生产动态资料符合度高,为明确优质储层分布、气藏动态分析、储量动用状况评价、气井生产管理及合理调整等提供了可靠的地质依据。 相似文献