接近表面磁力显微镜成像方法的研究

在当今信息社会时代，需要存储的信息总量正在急剧增加。与光存储技术和半导体存储技术相比而言，磁记录技术占领着几乎90％的存储市场。磁力显微镜( magnetic force microscope，MFM)的发展与磁记录工业密切相关。然而，从1987年至今，MFM的分辨率仍然停留在50~10 nm的水平，传统思路已经很难再实现突破。本论文基于MFM探针的窄带－频率调制机理，发展接近表面磁力显微镜方法，实现对纳米结构中磁畴状态的超高分辨率成像。该工作的关键在于合理利用MFM探针的窄带－频率调制机理，优化设计动态信号处理模块，精确控制探针－样品间距(5 nm 以下)，独立分离磁力像和表面像(磁力像为交流信号，原子力像为直流信号)，由此测量和解释纳米尺度磁畴结构。该方面的工作对于纳米磁畴结构的设计、核心磁性器件的研究起到非常关键的作用，为下一代磁记录技术的发展提供了新型的有力工具。     

32-site microelectrode modified with Pt black for neural recording fabricated with thin-film silicon membrane

Multi-electrode array is an important tool in the study of neural-network,cognition,remembrance,as well as brain-computer-interface,etc.Fork-like 32-site microelectrodes are developed with silicon.By use of integrated circuit technology,the length of the electrodes,the area of the recording sites,as well as the spaces between the sites are closely controlled.SiO2/SiNx/SiO2composite dielectric membrane and Pt black are introduced to improve the characteristics of the electrodes.The whole thickness of the thin-film probe was 21μm.By combining the modifying process with the micro-fabrication method,this kind of silicon based microelectrode satisfies high-density recording and the performance characterization is evaluated by test in vitro and in vivo.     

Recording and thermo developing of latent phase holograms in the photosensitive polymer material based on anthracylacetonatoboron difluoride

The diffraction efficiency of photoinduced gratings recorded in polymethylmethacrylate doped with anthracylacetonatoboron difluoride was shown to be increased from 8% to 70% due to the post-exposure heating of the material to 75 °C. Mechanism of the thermal development was determined to be the diffusion of the initial photoactive additives molecules and the photoproduct. This process shifts the minimum of the material frequency-contrast characteristic into the low-frequency region as well as significantly increases the amplitude of the refractive index modulation for gratings with the spatial frequencies up to 2500 mm⁻¹.     

建筑智能化系统新技术及应用

介绍近几年在建筑智能化领域受到关注的统一通信、会议录播、智能视频分析、无线调度及巡查、停车管理等新技术及其应用,与传统解决方案相比,能够更好地适应现代用户使用及管理上的需求,提高智能建筑的综合使用功能和物业管理的效率.     

基于激光诱导荧光成像技术的截面含气率检测研究

截面含气率作为气液两相流动过程中的基本参数之一,对石油管道的开采、输运,核反应堆冷却塔的设计等过程具有重要意义。本文提出了基于激光诱导成像技术和高速摄录系统的截面含气率直接检测方法,有效的避免管道曲率和介质折射率导致的光学畸变。在河北大学多相流循环装置进行实验,测量了18个流量点,液相流量测量范围10～35 L/min,气相流量测量范围2.0～3.0 L/min。运用计量比对的思想,对两种检测技术获得的截面含气率值求取偏差并进行修正,最大偏差仅为0.014 59。结果表明两种方法得到的截面含气率值具有较好的一致性,证明本文提出的荧光成像技术对气液两相分层流截面含气率的检测是有效的。     

一种自动扶梯运行状态记录和故障报警系统的研发

介绍了一种自动扶梯运行状态记录和故障报警系统的软、硬件结构．给出了该系统的性能试验测试结果。测试结果表明．该系统可以准确地监测自动扶梯的运行状态和故障,从而在提高自动扶梯运行安全性能方面可以发挥重要作用。     

Effects of Ag layers on the microstructure and magnetic properties of CoPt/BN multilayer films

Ag/[BN/CoPt]5/Ag and [BN/Ag/CoPt]5/Ag thin films were deposited on glass substrates by magnetron sputtering and then annealed in vacuum at 600 ℃ for 30 min.The structures and magnetic properties of CoPt/BN multilayer films were investigated as a function of Ag layer thickness.It was found that the face-centered tetragonal (fct) (001) texture of CoPt was improved greatly by introducing the Ag toplayer or sublayer together with an Ag underlayer.Good (001)-oriented growth,low intergrain interactions as well as...     

磁记录用Co-Cr-Pt合金的制备及其表征

用真空熔炼法制备得到的CoCrPt合金铸锭,采用不同淬火条件优化其相组成,采用1000℃保温50 min后热轧的工艺对其进行热加工;利用X射线衍射仪(XRD)、金相和扫描电子显微镜(SEM)分析合金的结构和形貌.结果表明:所制备的CoCrPt合金铸锭由高温相面心立方固溶体(αCo)和低温相密排六方固溶体(εCo)及氧化...     

广播电台录制机房的声学设计与实现

主要介绍了典型电台录制机房从设计到建设完成的整个过程,从土建声学、工艺设计、操作台设计、设备配置选型几个方面逐一说明了录制机房建设过程中的经验,以及需要重点考虑和注意的问题。