Specimen preparation of porous Au for transmission electron microscopy using cryo ion-milling

Porous Au specimens suitable for transmission electron microscopic investigations were prepared by the Ar ion-milling equipped with a cryo-system. The cryo technique enabled the preparation of an artifact-free specimen, avoiding the deposition of Au particles induced by ion-milling. This result demonstrates that cooling is necessary for defect-free preparation of the specimens.     

Specimen preparation for high-resolution transmission electron microscopy using focused ion beam and Ar ion milling

We have developed a focused ion beam (FIB)-Ar ion-milling technique for high-resolution transmission electron microscopy. A micrometresized specimen was mounted on a cross section of metal foil of a few micrometres thick, using FIB microsampling. Following this, a 2 degrees wedgeshaped part was made in the specimen using FIB. Finally, the specimen was milled using an Ar ion beam to remove the FIB-damaged layers. We applied the FIB-Ar ion milling technique to a CeO(2)/Gd(2)Zr(2)O(7) multilayer specimen, resulting in the crystal lattice fringes of both layers being clearly observable in comparison to a specimen finished using a Ga ion beam at an accelerating voltage of 10 kV.     

Transmission electron microscopy and atom probe specimen preparation from mechanically alloyed powder using the focused ion-beam lift-out technique

The preparation of transmission electron microscopy (TEM) and atom probe-field ion microscopy (AP-FIM) specimens from mechanically alloyed Ti-Cu-Ni-Sn powder has been explored. Applying the focused ion beam (FIB) based in situ lift-out technique, it has been demonstrated that specimen preparation can be carried on single micrometre-sized powder particles without the use of any embedding media. Since the particles did not incorporate any micropores, as revealed by cross-sectioning, the standard procedure known for bulk samples could be simply implemented to the powder material. A sequence of rectangular cuts and annular milling was found to be a highly efficient way of forming a tip-shaped AP-FIM specimen from a square cross-section blank. A Ga level < or =1 at.% was detected if a low beam current of 10 pA was chosen for the final ion-milling stages. Implanted Ga ions were mostly confined to a zone of about 2 nm in thickness and indicated that ion-induced structural transformations were negligible.     

Examination of electrostatic potential distribution across an implanted p-n junction by electron holography

In the manufacture of semiconductor microelectronic devices, a p-n junction is formed usually by implanting a high concentration of impurity into a less heavily doped region and then heat annealing. A Si/Si p-n junction test sample has been made following the above practical process and thinned for electron holographic observation by using argon ion-milling. From the reconstructed phase image, the phase shift induced by potential drop across p-n junction can be seen clearly. To characterize quantitatively this potential drop, the mean inner potential V0 of silicon was measured precisely by electron holographic method. By measuring 25 different crystalline silicon spheres with diameter ranging from 40 to 170 nm, an average result of V0 = 12.16 +/- 0.83 V was obtained. By using this V0 value, a quantitative measurement yields the potential drop approximately 0.70 V, which is reasonably consistent with expected Si/Si junction parameter. The thickness of electric dead layer in depletion region produced from this measuring is approximately 20 nm on each sample surface.     

基于虚拟仪器技术的激光雷达测量控制平台

虚拟仪器具有性能好、集成度高、界面友好,控制方便、扩展性强等特点.设计了一个基于虚拟仪器技术的激光雷达控制平台,把激光雷达控制、检测、数据分析单元有机地组合在一起,通过计算机虚拟面板操作雷达系统控制、检测和数据处理单元,使得激光雷达控制更为方便安全,信号分析更加实时有效,建立了激光雷达的通用信号平台.     

近距爆破源振动采集系统

本文根据工程爆破测试的需要,提出了一种近爆点的振动信号采集节点的设计方案。该节点中使用一种新型的MEMS拾振器,采用Altera公司FPGA作为主控制器芯片,其中集成控制逻辑单元与NiosII软核嵌入式处理器,二者结合成为单芯片控制器方案。控制器运用多路FIFO进行数据缓冲,顺序传输数据至外部存储器,实现了多路数据的同步采集。拾振器与数据记录仪结合成为一体化的信号采集节点。该节点采样频带宽,体积小。适合近爆区域恶劣环境地震波信号的采集,节点可以灵活布置组成不同测试方案。     

大型压缩机机组仪表的现场检修技术研究

大型压缩机的运转对于仪表的使用具备较高的要求,本文首先对大型压缩机的仪表进行了状况分析,并对仪表各类使用过程中的维修检测技术进行了研究处理,结合仪表拆除的特点,对维修技术实施了研究,并根据检查性质的技术特点,对仪表重新安装技术进行了制定,使得大型压缩仪表机组可以在各类应用阶段都得到维修技术的有效支持,保证压缩机使用性能的优化升级.     

雷达信号分析虚拟仪器的设计与实现

虚拟仪器技术在众多领域得到了广泛的应用。文中针对雷达自动测试系统中对虚拟仪器的需求，分析了目前流行的虚拟仪器编程软件Labwindows／CVI在数值分析和信号处理方面的不足之处，提出了一种在Labwindows／CVI环境下利用ActiveX技术调用MATLAB工具箱中的函数，从而实现混合编程构建虚拟仪器的简单易行的方法，并用该方法实现了雷达信号分析虚拟仪器的设计。     

XDSL信号测试专用虚拟频谱仪的设计

功率谱密度是通信信号非常重要的参数，所以在通信的各个阶段都需要对功率谱密度进行测量。在接入网产品的开发中，有多个产品要同时进行开发，因此需要多台频谱分析仪。然而，频谱分析仪属于贵重仪器，配备多台频谱分析仪将导致开发成本增加。虚拟仪器的出现解决了这一问题。这里给出了XDSL接入产品测试专用的虚拟频谱分析仪设计的方法，实践表明，它具有功能齐全价格低廉的优势，作为传统频谱分析仪的替代，虚拟频谱分析仪能够极大的降低仪器的投资。     

基于LabVIEW的心电信号检测处理系统设计

介绍一种基于虚拟仪器LabVIEW的心电信号检测处理系统,阐明了虚拟仪器的基本概念及其在医学测量系统的应用,具体给出了心电信号放大、隔离电路的设计方案,借助数据采集DAQ卡PCI6070E实现对心电信号进行采集,通过图形化语言的编程对采集的心电数据进行分析、存储、共享。该系统可实现心电生理信号实时采集显示、心电信号HRV分析等功能,构造一套比较实用的心电虚拟仪器,对虚拟仪器在医学生物信号处理和医疗仪器开发方面有一定的参考价值。     

新型中医舌象分析仪关键技术研究

针对现有舌象采集装置在进行舌象信息采集时,不能满足卧姿病人的临床检测需要,且体积较大不方便携带,我们设计了新型舌象采集装置.该装置采用闪光灯作为仪器光源,构造了漫射照明条件,在较小的体积范围内产生高显色、均匀的照明环境.本文对新型采集装置进行了实验研究,并确定了各项采集参数.对于新型装置光学成像环境改变所引起的舌图像颜色数据变化,运用校准色板,采用离线彩色校正算法,实现了图像从新型舌象采集装置光学环境到标准环境的颜色转换,从而最终实现各舌象指标分析.实验结果证明了新型舌象分析仪的有效性.     

HgCdTe Research at FFI: Molecular Beam Epitaxy Growth and Characterization

This paper presents results from recent work on molecular beam epitaxy growth of HgCdTe at the Norwegian Defence Research Establishment (FFI), including studies of material properties and fabrication of photodiodes and nanostructures. Systematic studies of defect morphology in HgTe and Hg_1−x Cd _x Te have revealed that there is a minimum in the area covered by defects just below the onset of Te precipitation. The shape and density of microvoids in HgTe can be used to determine the deviation from the optimal growth temperature. This can be further related to the optimal growth temperature of Hg_1−x Cd _x Te with any Cd mole fraction by thermodynamic calculations. A mechanism for the formation of microvoids and needles has been presented. Photoluminescence (PL) has been used to study layers without doping and with Hg vacancy, Ag, and In doping. Planar photodiodes with high dynamic resistance and good quantum efficiency were fabricated by ion-milling vacancy-doped mid-wave and long-wave infrared layers. Quantum wells (QWs) with good crystallinity and high PL light output have been grown. Surface patterning has been found to enhance light emission from HgCdTe thin-film and QW samples by ∼30%. Single-crystal HgTe and segmented HgTe/Te nanowires have been grown, and the resistivity of the nanowires has been measured by conductive atomic force microscopy (AFM), where the AFM tip has been used as a mobile electrode.     

瞬时通断测量仪测量方法

详细分析了继电器抖动测试试验过程,以及在此试验过程中瞬时通断测量仪的作用。在充分讨论瞬时通断测量仪工作原理和波形采集过程的基础上,总结出继电器触点动作时采集点电压变化规律,并提出在测量瞬时通断测量仪中模拟继电器开关动作的方法;同时,通过建立起一套测量此类设备的通用测量装置,解决了此类设备的测试手段和测试方法问题。     

透射式能见距离激光测量仪的测量精度及受后向散射能的影响

本文研究了透射式能见距离激光测量仪的测量精度及其受后向散射能的影响。导出了能见距离的测量误差、能见距离、仪器与合作目标间的距离三者之间的关系,分别讨论了当仪器与合作目标间的距离确定时,在不同的能见距离下以及当能见距离确定时,在不同的仪器与合作目标间的距离下能见距离的测量精度及其受后向散射能的影响。分析了接收镜头口径大小对能见距离测量精度的影响。     

PTCR阻温特性曲线实验室用测试系统

介绍了一种利用计算机进行PTCR阻温特性的自动数据采集及参数处理的系统,叙述了该仪器的结构及原理,详细介绍了仪器的硬件和软件。本系统能够方便地应用于实验室的样品测量。     

激光在线长度测量仪

介绍一台在线测量的激光测长仪的工作原理和特点，测量精度优于１％，可对钢材，电缆、布匹、纸张等产品在生产过程中进行实时长度测量。     

基于AM-OLED的汽车仪表显示

分析了汽车仪表发展趋势,对AM-OLED与其他显示面板进行比较,提出了基于AM-OLED的汽车仪表显示方案。仪表信息经嵌入式处理器处理后以数字视频形式输出。FPGA接收视频信号,采用分形扫描方式控制AM-OLED面板显示图像。在AM-OLED上显示的汽车仪表图像清晰度高、对比度强、色彩亮丽。     

热敏电阻阻温特性曲线测试系统的研制

通过标准ＲＳ－２３２串行接口把计算机同智能仪表结合起来,组成热敏电阻阻温特性曲线测试系统,通过外围接口电路通道转换和控温,计算机通过串口由智能万用表进行数据采集,由软件实现参数计算和曲线显示。     

关于转向参数测试仪的改进建议

在检验检测厂内机动车辆的过程中，转向参数测试仪对于转向系统的检验检测起着至关重要的作用。因此，如何提高检测仪器的精度和准确性成了检验检测人员日益关注的问题。本文简要分析了目前该仪器在检测厂内机动车辆的应用中存在的不足之处，并提出了改进仪器的措施。     

位标器陀螺转子动平衡检测仪的研制

研制了一种全自动位标器陀螺转子动平衡测试仪，介绍了各部分功能实现的相关原理和措施。该仪器使用可变光栏黑体和反射式平行光管模拟不同大小、距离的目标，并创新性地采用激光测量的方法测量微小的绕动角。他结合光学方法和传统电测方法的优点实现了位标器陀螺动平衡的精确测量，只需要简单的操作即可显示绕动角和振动量的频率、振幅、相位。该仪器中绕动测量的方法可广泛用于许多陀螺系统的检测，特别在精密陀螺系统动平衡检测中具有推广价值。