锌镍电池用包覆氧化铟的氧化锌的性能

用化学沉积法制备密封锌镍电池负极材料包覆氧化铟(In2O3)的氧化锌(ZnO)。用XRD、TEM、Tafel曲线及充放电等方法,对样品进行分析。In2O3在ZnO表面为部分包覆(1.5%的包覆量);包覆后的ZnO具有更好的耐腐蚀性能,且循环性能良好,第179次1.0C循环(充、放电限压分别为2.1 V、1.4 V)的容量保持率为81%。     

纳米氧化铟粉体的制备及其在碱性锌锰电池中的应用

用共沸蒸馏法制备了纳米氧化铟粉体,对粉体的物理化学性能和缓蚀效果进行了测试。结果表明:制备的氧化铟粉体为纯度高、分散性好的纳米级超细粉体,同时具有良好的抑制气体产生的作用,可以作为碱性锌锰电池中的代汞缓蚀剂。     

靶材密度对射频磁控溅射法制备ITO薄膜性能的影响

以不同密度的氧化锡铟（ITO））靶材为原料,采用射频磁控溅射法,在室温下沉积并经750℃退火,获得了电阻率为1．56×10^-4Ω·cm、可见光透过率为87％的ITO薄膜。对不同密度靶材制备的ITO薄膜的微观结构、电学及光学性能进行了表征与探讨。结果表明,采用射频磁控溅射法时,不同靶材密度对ITO薄膜的沉积速率、结构、电学和光学性能均无显著影响。该结果为采用低密度ITO靶材制备高品质ITO薄膜提供了一个新的思路。     

石墨烯负载NiO纳米盘的制备与储锂性能

采用水热-自组装法制备了石墨烯负载氢氧化镍纳米盘,再将其煅烧处理,得到石墨烯负载氧化镍纳米盘(GANON)复合材料。研究表明,这种独特的2D-2D复合材料中石墨烯片层与Ni O纳米盘之间具有较大的接触面积,提高了不同基元之间的电子输运性能,并增强了其结构稳定性,从而实现较高的储锂容量和良好的循环性能。GANON电极的首周放电和充电比容量分别为1 103.7和685.7 m Ah/g,首次库仑效率为62.1%;30周的充电比容量为624.2 m Ah/g,容量保持率为91%。GANON电极的可逆转化储锂反应主要分两步进行;其复合材料较好的结构稳定性能有效抑制电极表面SEI膜的反复破损/修复过程。     

氧化石墨烯对钒液流电池电解液性能的影响

以氧化石墨烯(GO)作为全钒液流电池正极电解液添加剂,研究含量不同的GO对钒电池正极电解液电导率、循环伏安曲线及电池容量和能量效率的影响。结果表明,正极电解液的电导率先随GO添加量的增加而增大,在添加量为1%(质量分数)时达到最大值326 m S/cm,随后减小;扫描速度为5 m V/s的循环伏安曲线表明当GO含量为1%时,电解液具有最大的氧化峰电流和还原峰电流,分别为172和127 m A;首次循环与第20次循环的伏安曲线对比表明电解液稳定性很好,此时电解液性能也最佳;用GO含量为1%的电解液作为正极电解液组装静态电池,电池30次充放电循环的平均容量比空白电池提高了9.8%,容量保持率和能量效率为85.30%和79.26%,分别比空白电池的79.40%和75.35%有所提高。     

水热法制备还原氧化石墨烯-硫复合材料的性能

以湿法制备的硫溶胶和氧化石墨烯为前驱体,采用水热法还原不同酸碱体系的氧化石墨烯,制备石墨烯-硫复合材料。通过XRD和场发射扫描电子显微镜(FESEM)等对产物进行分析。石墨烯以薄膜状包覆在硫颗粒表面。恒流充放电、交流阻抗和循环伏安测试结果表明:180℃、酸性条件下水热12 h制备的复合材料电化学性能较好,以0.2 m A/cm2的电流密度在1.5~3.0 V充放电,首次放电比容量为803.72 m Ah/g,循环20次衰减至592.40 m Ah/g,容量保持率为73.71%。     

石墨烯/线状二氧化锰的合成及性能

在300℃下、空气气氛中还原氧化石墨(GO),制得石墨烯(GN),并与二氧化锰(MnO_2)复合,在异丙醇溶液中制备GN/MnO_2复合材料。通过XRD、场发射扫描电子显微镜和高分辨拉曼光谱等方法,对产物进行分析。热还原制备的GN为薄的片层状结构;复合材料中,线状MnO_2在片层状GN表面生长。用循环伏安和恒流充放电测试产物的电化学性能。在1 mol/L Na_2SO_4电解液中,当电流为100 mA/g、电位为0~0.8 V时,GN和MnO_2的比电容分别为108 F/g和119 F/g,复合材料的比电容为181 F/g。     

石墨烯纳米片-氧化亚钴负极材料制备与表征

采用水热法结合500℃高温焙烧制备了新型高性能锂离子电池负极材料石墨烯纳米片-氧化亚钴(GNS-CoO)复合材料。采用XRD及TEM等手段对石墨烯纳米片-氧化亚钴复合材料结构和形貌进行表征,并对其电化学性能进行测试。结果表明,石墨烯纳米片-氧化亚钴复合材料的循环性能明显优于氧化亚钴,以200mA/g进行充放电得到首次放电比容量为1040.2mAh/g,50次循环后放电比容量为1027.8mAh/g,显示出良好的循环稳定性。     

Few layered graphene oxide thin films: A potential matrix for immunosensors

ABSTRACT

We have synthesized highly exfoliated graphene oxide (GO) and used it for the fabrication of electrochemical immunosensor. The thin films of GO were spin coated onto ITO/glass substrate and thereafter Bovine Serum Albumin (BSA) antibodies (Ab) were immobilized using EDC-NHS binding chemistry to design immunobioelectrode. The graphene oxide films were characterized using different spectroscopic techniques viz FT-IR, UV-Vis spectroscopy and HRTEM. The electrochemical activity of designed immunoelectrodes was studied by cyclic voltammetry (CV) that revealed a quasi reversible behaviour of graphene oxide films. The differential pulse voltammetry (DPV) measurements of the fabricated immunoelectrodes showed successful detection of analyte at very low concentration ranges (50 fg/mL–100 ng/mL). The present study entails the potential of GO for the development of various immunosensors for different diseases.     

Reliability assessment of indium tin oxide thin films by accelerated degradation test

The thermal degradation behavior and reliability of indium tin oxide (ITO) thin films deposited on glass substrates using radio frequency (rf) magnetron sputtering were investigated over the temperature range of 200–250^∘C in air. Accelerated degradation test (ADT) was performed to assess the reliability of ITO films. The lifetime of ITO films under normal operating condition (150^∘C) can be predicted to be 1.148 × 10⁵ h via statistical analysis and modeling of data acquired from ADT. The lifetime of ITO films was also evaluated using finite element analysis (FEA) based on the assumption of oxygen diffusion mechanism.     

纳米锑掺杂二氧化锡担载IrO_2催化剂的制备与性能

在非氯盐体系下,采用化学共沉淀法制备纳米级锑掺杂二氧化锡(ATO)粉体材料,分析锑掺杂浓度、前驱体pH值和前驱体煅烧温度对电导率的影响;采用优化的Adams法,以纳米ATO粉体为载体,制备担载型析氧催化剂二氧化锒(IrO_2)/ATO,并进行XRD分析、电化学阻抗及极化曲线测试。制备ATO粉体电导率最大时(0.581 S/cm)的条件为:Sb掺杂浓度10%,pH值为3.5,煅烧温度为600℃。采用IrO_2/ATO催化剂的单体电池,在800mA/cm~2、80℃时,所需槽电压仅为1.40V。     

基于多尺度Gabor滤波器的角点检测

为了克服在不同图像上的尺度选择问题,提出了一种基于边缘轮廓线的多尺度Gabor滤波器的角点检测算法。该算法首先利用Canny边缘检测算子提取图像的边缘轮廓;进而用一组构建好的4个尺度8个方向Gabor滤波器的虚部对图像进行平滑,并计算每个像素在其相同尺度下各个方向上Gabor滤波器虚部响应的归一化的和;最后将每个边缘像素点在所有尺度下的乘积作为新的角点测度, 当角点测度大于预设阈值时,则认定该点为角点。将实验结果与经典的Harris、CPDA和He&Yung角点检测算法进行比较,提出的算法在检测准确率、定位误差、噪声稳健性性能指标上,都取得了更好的结果。     

Synthesis and characterization of indium tin oxide (ITO) nanoparticle using gas evaporation process

In this paper, indium tin oxide (ITO) nanoparticle was synthesized by gas evaporation process, and its physical properties such as particle size, specific surface area, crystal structure, and composition ratio according to the heat-treating conditions were investigated to optimize them. The source material was charged in a chamber with vacuum circumstance of 1×10⁻⁵ torr, and the oxygen gas was supplied during evaporation. The In_xO_ySnO_z nanoparticle was synthesized, and the nanoparticle was heat-treated to have optimal point of particle size, crystal structure, and composition, etc. The synthesized nanoparticle was heat-treated with controlling such parameters as heat-treating temperature and environmental gas. Particle size, specific surface area, crystal structure, and concentration ratio of the synthesized ITO nanoparticle by using the method were analyzed with high resolution transmission electron microscopy (HRTEM), BET surface area analyzer, X-ray diffraction (XRD), and energy dispersion spectroscopy (EDS). As a result, in case of ITO nanoparticle synthesized at 300^∘C, its mean particle size is 5 nm and the surface area exceeds 100 m²/g. The XRD analysis indicates that the crystal structure of the particle is cubic one with orientation of (222), (400), (440). Also, the EDS analysis demonstrates that the concentration ratio of indium and tin is 91 at% and 9 at% in the lattice of the ITO nanoparticle. Since the lower sized ITO nanoparticle produces the ITO sputtering target with higher density and the ITO sputtering target with higher density makes the high quality ITO electrode, the synthetic condition of 300^∘C is considered to be optimal condition for enhancing the high quality ITO electrode.     

SUSAN算子在车辆检测中的应用研究

SUSAN算子是一种基于图像灰度的类积分算法。该算法利用圆形模板对图像中的感性区进行扫描,经由对模板中心点和非中心点灰度值比较、运算。所得运算结果与阈值进行比较,从而判断此中心点是否为兴趣特征点,实现对图像特征点的提取。特征检测前首先利用Hough变换检测道路边界线以确定路面区,然后应用SUSAN算子在检测出的路面区中对车辆进行特征提取。可以快速准确地提取出行驶中车辆的兴趣特征点。     

基于全卷积神经网络的坝面裂纹检测方法研究

针对常规裂纹检测方法难适用于坝面裂纹检测的问题,提出一种基于全卷积神经网络的裂纹检测方法,主要解决混凝土坝面裂纹的定量化检测问题。该检测方法引入图像预处理与形态学后处理相结合的方式,分别对原始数据和预测结果进行优化,提升检测精度;并根据坝面数据特点对传统FCN(fully convolutional network)网络进行改进,得到针对性更强的裂纹检测网络C-FCN(crack fully convolutional network),提升对裂纹检测的准确率;结合成像原理提取定量化信息,避免繁杂的相机标定工作,更加高效客观。利用该检测方法对实际工程进行实测,像素准确率、召回率和交并比分别达到75.13%、86.84%和60.15%,相比传统FCN网络,三项指标分别提升5.61%、16.56%、13.22%,同时定量化误差小于5%,裂纹平均宽度均不超过5 mm。该检测方法能够实现对坝面裂纹的精准识别和定量,为坝面后期风险评估和维护提供有力的数据支撑,具有显著的工程意义。     

Effect of Thickness on the Electrical and Optical Properties of Sb Doped SnO2 (ATO) Thin Films

This work reports the preparation and characterization of (SnO₂) thin films doped with 7 mol% Sb₂O₃. The films were prepared by the polymeric precursor method, and deposited by spin-coating, all of them were deposited on amorphous silica substrate. Then, we have studied the thickness effect on the microstrutural, optical and electric properties of these samples. The microstructural characterization was carried out by X-ray diffraction (XRD) and scanning tunneling microscopy (STM). The electrical resistivity measurements were obtained by the van der Pauw four-probe method. UV-visible spectroscopy and ellipsometry were carried out for the optical characterization. The films present nanometric grains in the order of 13 nm, and low roughness. The electrical resistivity decreased with the increase of the film thickness and the smallest measured value was 6.5 × 10^{– 3} cm for the 988 nm thick film. The samples displayed a high transmittance value of 80% in the visible region. The obtained results show that the polymeric precursor method is effective for the TCOs manufacturing.     

锅炉受热面联络管内壁氧化皮层缺陷分析

针对开封火电厂2×600 MW机组扩建工程中锅炉受热面联络管内表面上存在氧化层的问题,分析高温下钢铁表面氧化层组织结构,比较3种铁氧化物的PBR比及膨胀系数,得到氧化层容易剥离的原因;并确认硫酸酸洗法可以有效去除受热面联络管内表面上氧化层.     

基于小波分解的群落流量异常检测

针对大规模高速网络海量数据处理和异常检测率较低的问题,将群落概念引入流量异常检测领域,用小波三层分解和偏离值结合的检测方法,实验性地证明了基于群落的检测比基于网络的检测能提供更加准确和高效的检测结果。因为以群落为观察范围,可以避免对群落的攻击被其他群落的无关网络活动所掩盖,并且可以分流数据。文中对群落检测所使用的特征集进行了研究,在总结已有基于Netflow记录的特征的基础上,用基于相关性的方法剔出了强相关的特征,优选出适合群落检测的特征集,避免了当前基于Netflow的异常检测中随意选取特征所造成的信息冗余。     

Fault detection in induction motors using Hilbert and Wavelet transforms

In this work, a new on-line method for detecting incipient failures in electrical motors is proposed. The method is based on monitoring certain statistical parameters estimated from the analysis of the steady state stator current (for broken bars, saturation, eccentricities, and bearing failures) or the axial flux signal (for coil short-circuits in the stator windings). The approach is based on the extraction of the envelop of the signal by Hilbert transformation, pre-multiplied by a Tukey window to avoid transient distortion. Then a wavelet analysis (multi-resolution analysis) is performed, which makes the fault diagnosis easier. Finally, based on a statistical analysis, the failure thresholds are determined. Thus, by monitoring the mean value estimate it is possible to detect an incipient failure condition on the machine.     

空中小目标实时检测的快速局部熵算法研究

基于局部熵的空中小目标检测算法时间复杂度高,难以满足工程应用中对系统实时性的要求,严重影响了此算法在工程中的实际应用,且与此相关的优化研究很少.针对这一现状,提出了一种快速局部熵算法,此算法将Box-Filtering优化技术引入传统局部熵计算公式的泰勒展开,采用迭代方式替代传统方法,剔除了大量冗余计算,并详细给出优化...