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131.
132.
刘晓巍 《大理学院学报:综合版》2014,(9):69-72
奘寺学童现象是云南傣族聚居区独特的教育现象。奘寺学童现象对教育法规因应提出的要求是统合校内外的教育资源,确立少数民族现代化进程中的文化主体地位,并谨慎处理教育平等、国家文化与地方文化、外来文化与本土文化的关系。 相似文献
133.
A novel glucose biosensor based on graphene nanosheets (GNs) modified gold nanowire arrays (AuN- WAs) electrode was constructed. Highly ordered gold nanowire arrays were prepared by direct electrodeposition in anodic aluminum oxide templates. GNs were synthe- sized through a public route involving graphite oxidation, exfoliation, and chemical reduction. Field emission scan- ning electron microscope and high-resolution transmission electron microscope were employed to characterize the as- prepared AuNWAs and GNs. Glucose oxidase was immobilized on the surface of GNs-AuNWAs modified electrode via a cross-linking method. The cyclic voltam- metry results showed that the GNs-AuNWAs-based glu- cose biosensors have high catalysis activity to hydrogen peroxide (H2O2) than those modified with GNs or AuN- WAs only. Furthermore, amperometric response was employed to detect glucose concentration owing to its simplicity, high selectivity, and relative low cost. Glucose biosensors based on GNs-AuNWAs showed excellent performance with high sen- sitivity of 40.25 μA cm^-2 (mmol/L)^-1, low detection limit of 0.02 mmol/L, and a linear range from 0.02 to 3 mmol/L. 相似文献
134.
Over the past ten years,the enthusiasm to harness small RNA molecules,mainly small interfering RNAs(siRNAs) and microRNA mimics,into therapeutic weapons has never been quenched.However,a major obstacle hindering the clinical application of these small molecules is how to efficiently and precisely deliver siRNAs in vivo into target cells to silence target genes.An international collaborative study led by Song Erwei from the Memorial Hospital of Sun-YatSen University and Wang Jun from Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences of University of Science and Tech- 相似文献
135.
Graphene-based hybrid materials and their applications in energy storage and conversion 总被引:1,自引:0,他引:1
Graphene attracts more and more scientists and researchers owing to its superior electronic,thermal,and mechanical properties.For material scientists,graphene is a kind of versatile building blocks,and considerable progress has been made in recent years.Graphene-based hybrid materials have been prepared by incorporating inorganic species and/or cross-linking of organic species through covalent and/or noncovalent interactions.The graphene-based hybrid materials show improved or excellent performance in various fields.In this review,we summarize the synthesis of graphene and graphene-based hybrid materials,and their applications in energy storage and conversion. 相似文献
136.
针对公路装配式空心板桥,在分析影响桥梁加宽效果关键因素的基础上,提出了预压加宽施工新工艺,并在工程实例桥加宽改造施工中进行的应用验证,该施工工艺可用于类似桥梁的加宽改造. 相似文献
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For the improvement of accuracy and better fault-tolerant performance, a global position system (GPS)/vision navigation (VISNAV) integrated relative navigation and attitude determination approach is presented for ultra-close spacecraft formation flying. Onboard GPS and VISNAV system are adopted and a federal Kalman filter architecture is used for the total navigation system design. Simulation results indicate that the integrated system can provide a total improvement of relative navigation and attitude estimation performance in accuracy and fault-tolerance. 相似文献
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支持垂直引导进近的多星座RAIM算法 总被引:3,自引:0,他引:3
为了充分利用未来的全球导航卫星系统(GNSS)中多星座多频点的卫星信号,使接收机自主完好性监测(RAIM)技术能够用于垂直引导进近(APV)飞行阶段,提出了一种基于双星故障假设的多星座RAIM算法。算法将全部可见卫星分为3组,分别计算定位解,对3个分组定位解加权平均作为最终的定位解,通过迭代寻找最优加权因子,使得在满足定位精度要求的前提下极大化算法的可用性。仿真结果表明:该算法能够以100%的可用性支持APV-Ⅰ飞行阶段,以高于99%的可用性支持APV-Ⅱ飞行阶段。 相似文献