电阻绝缘检测中低压脉冲信号注入法的算法改进

在有源式低压脉冲信号注入法的基础上,重新推导了计算电阻值的数学模型,并设计了一种运用该模型的有源式动力电池绝缘电阻监测系统,该系统可以有效地解决部分无源式和有源式绝缘检测法无法有效精确测量同时下降的正负端绝缘电阻与正负端单侧绝缘电阻的问题.此外,通过台架实验验证了该监测系统的有效性,在改进电动汽车动力电池监测系统方面具有一定的应用价值.     

C3N4/ZnO复合材料可见光下的甲醛光电气敏性能

以水热法合成的ZnO纳米棒花为载体,将C_3N_4定量负载在其表面,制备C_3N_4/ZnO复合材料.由于C_3N_4与ZnO的能级匹配,可有效促进其光生电荷的分离,降低光生电荷复合率,显著提高载流子浓度,使其光电流明显增加.C_3N_4与ZnO质量比为2%的样品(2%C_3N_4/ZnO)性能最佳,其光电流在370 nm处可达120μA,为纯ZnO的2.4倍.在室温可见光下,2%C_3N_4/ZnO样品对HCHO的光电气敏响应值可达122%,比纯ZnO高4倍左右.结果表明,适量C_3N_4的负载有效延长了光生电荷的寿命,使ZnO材料在可见光区对HCHO气体表现出高效的光电气敏性能.     

一种基于四叉树划分的改进ORB算法

原ORB （oriented FAST and rotated BRIEF）算法提取的图像特征点经常出现“扎堆重叠”现象，其分布较为密集且缺乏尺度不变性，因而容易造成图像特征点误匹配的问题。为了解决该问题，提出了一种基于四叉树划分的图像特征点提取算法。首先对图像建立尺度金字塔，然后使用四叉树划分图像并限制划分深度。用加速分段测试的特征（features fromaccelerated segment test，FAST）算法通过多个检测阈值对划分后的图像进行特征点检测。检测完毕后，根据划分出的子块总数和提取的特征点总数对划分出来的各个子块设置自适应阈值，提取ORB特征点。操作完成后通过采取非极大值抑制的方法筛选最佳特征点，并使用改良后的二元鲁棒独立基本特征（binary robust independent elementary features，BRIEF）算法计算得出特征点的描述符，最后进行特征点匹配。实验结果表明，本文算法提取的图像特征点较原ORB算法提取的效果在均匀程度上得到了明显地提升，冗余重叠的特征点数量减少，且在特征点提取速度方面较原ORB算法的提取速度提高了30%以上。     

An effective amperometric biosensor based on graphene modified gold nanowire arrays for glucose detection

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.     

Single-Chain Fragmented Antibodies Guided SiRNA Delivery in Breast Cancer

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-     

Graphene-based hybrid materials and their applications in energy storage and conversion

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.     

公路装配式空心板桥加宽预压施工新工艺研究与应用

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.     

变动中的人格权

人格权是以权利主体的人格利益为客体的民事权利.对人格利益的认定,随着时代的发展在逐步深入,所以人格利益的范围日益扩大,人格权的内容日益丰富,出现了许多新的人格利益.本文对此做一简单论述.     

类stober法可控制备单分散TiO2纳米微球

采用类Stober法,以钛酸正丁酯为钛源,反应温度为130℃,可控制备粒径尺寸均一的单分散TiO_2纳米微球.通过调节反应时间、溶液的pH值,单分散TiO_2纳米微球的直径可以在几十到一千纳米范围内被精确调控.利用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射(XRD)仪对所制备的TiO_2纳米微球进行了表征.结果显示样品为无定形结构,可通过进一步的水热晶化提高样品的结晶度.此单分散TiO_2纳米微球有望在光催化机理研究、太阳能敏化电池、光子晶体等方面具有很好的应用.     

小型制冷系统的稳态模拟

所建立的小型制冷系统模型包括压缩机、冷凝器、膨胀阀和蒸发器四个部件模型以及使系统封闭的 充灌量模型,实现了所有相关物性参数计算的程序化以便于模型的数值求解。在蒸发器模型中提出了析湿系数 的新算法,加速了模型的计算。用所建立的模型模拟工作参数的变化对系统性能的影响,其结果与实际规律相 符合,证明了该模型的正确性。根据模型得出的定量结果可分析各性能参数变化的相互影响,并对性能参数的 敏感性进行分析,为系统优化和控制提供理论依据。此外,换热器模型还可独立用于各种换热器性能的分析与 优化。