Understanding silica-supported metal catalysts: Pd/silica as a case study

Supported metal catalysts, particularly noble metals supported on SiO₂, have attracted considerable attention due to the importance of the silica–metal interface in heterogeneous catalysis and in electronic device fabrication. Several important issues, e.g., the stability of the metal–oxide interface at working temperatures and pressures, are not well-understood. In this review, the present status of our understanding of the metal–silica interface is reviewed. Recent results of model studies in our laboratories on Pd/SiO₂/Mo(1 1 2) using LEED, AES and STM are reported. In this work, epitaxial, ultrathin, well-ordered SiO₂ films were grown on a Mo(1 1 2) substrate to circumvent complications that frequently arise from the silica–silicon interface present in silica thin films grown on silicon.     

快重离子在石墨中引起表面及体径迹的STM研究

用多种快重离子辐照高定向石墨（HOPG），借助扫描隧道显微镜（STM）系统地研究了表面及体内缺陷，结果表明，离子在表面及解理面上都形成了小丘状的缺陷，且在表面较容易形成，可以用非连续损伤径迹结构来对其进行解释。     

纳米技术的研究现状与将来

纳米科学技术将成为２１世纪最重要的高技术之一。纳米技术的最终目标是直接操纵单个原子和分子，制造量子功能器件，从而开拓人类崭新的生产生活模式。文章评述利用电子束、离子束的精细技术和ＳＴＭ原子操纵技术的研究现状，介绍原子层蚀刻，单层抗蚀剂自形成蚀刻，纳米自然蚀刻和电子束全息纳米蚀刻等高技术前沿动态，展望纳米技术的发展前景。     

Surface structure of silver thin films on In2O3:Sn and Al2O 3 †

Surface structure of thin silver films (200 Å) on two technologically important films, indium tin oxide (ITO) and aluminium oxide, has been studied using scanning tunneling microscope. ITO films were prepared by reactive electron beam evaporation. Aluminium oxide films were prepared by oxidizing 2000 Å thick aluminium films evaporated on to H₂ terminated single crystal silicon substrates. The surface structure of silver on ITO and aluminium oxide appeared to be same and was characteristic of Stranski-Krastanov type. The observed asymmetry in the island shape was attributed to the anisotropic nature of the strain fields surrounding the nucleation centres.     

STM tunneling spectroscopy on high Tc superconductors

STM tunneling spectroscopy has been performed on the bulk single crystals of BiSrCaCuO (BSCCO) and the epitaxial thin films of YBaCuO (YBCO) at cryogenic temperatures. The STM images and tunneling spectra observed on the (001) surfaces can be classified into three cases; 1) Atomic image is visible. However, the tunneling spectrum shows semiconducting or smeared superconducting gap structures, depending on the tip-sample distance. 2) Clear atomic image can not be obtained. But, the tunneling spectrum shows flat bottom region with quite low zero bias conductance. 3) Tunneling spectra demonstrate gapless behavior, independent of the tip-sample separation. These observations support the quasi-2D electronic picture in whichs-wave like 2D superconducting layers are coupled with each other through the Josephson effect.     

动力后坐试验台数据采集系统设计与实现

为满足动力后坐试验台位移、速度数据高速采集的要求,介绍了一种以增量式编码器为位移传感器、以STM32F107VCT6MCU为下位机数据采集模块,采用MicrosoftVc＋＋6．0开发上位机试验软件的动力后坐试验台位移速度采集系统,实现了对试验中位移、速度数据的高速采集,并利用TeeChart控件实现速度位移曲线的绘制。现场试验结果表明该系统达到了设计要求,实现了数据的高速采集和曲线显示。     

大棚温湿度无线实时监控系统的设计

提出了一种基于ZigBee技术的大棚温湿度无线实时监控系统的设计方法。该方法以SOC芯片CC2530和内核为Cortex-M3的STM32F107及温湿度传感器为硬件平台,可实现对大棚内气体和土壤温湿度的实时采集及空间定位功能,同时可将采集到的数据通过ZigBee网络传输到监控中心。     

基于物联网技术的智能家居椅控制系统设计

针对国内外智能家居椅控制系统二次开发难度大、接口兼容性差等问题,基于物联网技术,对现有智能家居椅控制系统进行了二次开发。采用STM32控制器对智能家居椅控制系统的输入输出接口进行扩展,引入压力传感器、S型称重传感器、光电探测器对家居椅各个执行机构进行监测,开发了基于Java语言的微信客户端应用(APP)程序,实现了智能家居椅捶背力度调节、复合机构助起、阅读灯亮度调节等远程智能操控。智能家居椅捶背控制试验表明,捶背次数控制成功率约85.49%,捶背力度控制成功率约86.50%。复合机构助起试验表明,助起控制成功率约90%。阅读灯亮度调节试验表明,亮度调节成功率可达88.46%,系统可控性较高。采用物联网技术对智能家居椅控制系统进行了创新性设计,二次开发的控制系统可为互联网+智能家居的设计提供参考。     

带式输送机故障定位系统网关的设计

以带式输送机故障定位系统为应用背景,提出了一种基于STM32F103VE微处理器的CAN总线与Profibus-DP总线网关的设计方案。该网关在CAN网络中作为一个CAN通信节点,在Profibus-DP网络中作为一个从站;带式输送机沿线分布若干个CAN检测节点,每个节点负责检测其段内的4种传感器设备采集的实时数据,如果检测到故障信息,CAN检测节点就会向网关发送故障信息报文,网关接收CAN检测节点发送的报文并进行存储;当网关与Profibus-DP主站连通后,作为Profibus-DP从站的网关可以通过查询方式把故障信息报文传送到Profibus-DP主站中,从而实现故障定位功能。实际应用表明,该网关运行稳定、可靠,实现了带式输送机故障定位系统中CAN总线及Profibus-DP总线的互联。     

基于ENC424J600的以太网与串行接口转换技术

论述了在STM32系列的MCU上移植TCP/IP协议栈LwIP,并利用新型以太网控制器ENC424J600实现网络数据传输功能。该系统主要完成的功能是接收上位机发送的数据,并将这些数据转换成通用串行接口输出。ENC424J600是Microchip新推出的一款以太网控制器,其速度优于ENC28J60,同时为用户提供两种接口模式。本文介绍了其基于SPI接口模式下的实现过程,详细描述了该网卡驱动的硬件电路和软件流程。