弱磁场下法拉第效应的实验研究及可能应用讨论

利用了四频环形激光对磁场的高度敏感性测量了Tb玻璃(磁场范围0.8×10~(-5)T(Tesla)～10~(-9)T,ZF_2玻璃(0.21×10~(-4)T～1.89×10~(-4)T的费尔德常数(Verdet constant).在本实验精度范围内,得到了该常数大小和强磁场下的值一致.以此实验结果为基础,简要地讨论了用置于环形激光中的法拉第磁光材料感测地磁场的构思和发展前景.     

数字MMDS系统设计

介绍MMDS数字电视系统的整体架构与设计原理,MMDS的发射与接收,MMDS收发天线的技术特点,以及MMDS的现状与发展趋势。     

基于光学和扫描显微平台的微尺度实验力学检测技术和装置研究

本文基于光学和扫描显微平台,介绍了本研究组在微尺度实验力学检测技术和设备方面的最新研究成果。在检测技术方面涉及显微散斑干涉技术、微标记阵列检测技术、晶粒变形分析技术、光学探针动静态变形分析技术;在检测系统和装置方面介绍了新近开发的双视场薄膜检测系统、散斑微干涉系统、微标记检测平台、AFM和SEM单轴拉伸装置、三维微定位与加载系统、微力传感器及其标定装置、微动平台驱动装置等。探讨了微尺度实验力学检测中的问题和新的检测技术,给出了一些典型的应用和相关装置。     

Monte Carlo studies on the burnup measurement for the high temperature gas cooling reactor

Online fuel pebble burnup measurement in a future high temperature gas cooling reactor is proposed for implementation through a high purity germanium (HPGe) gamma spectrometer. By using KORIGEN software and MCNP Monte Carlo simulations,the single pebble gamma radiations to be recorded in the detector are simulated under different irradiation histories. A specially developed algorithm is applied to analyze the generated spectra to reconstruct the gamma activity of the ¹³⁷Cs monitoring nuclide. It is demonstrated that by taking into account the intense interfering peaks,the ¹³⁷Cs activity in the spent pebbles can be derived with a standard deviation of 3.0%(1σ). The results support the feasibility of utilizing the HPGe spectrometry in the online determination of the pebble burnup in future modular pebble bed reactors.     

多阶段深度学习单帧条纹投影三维测量方法

深度学习的应用简化了数字条纹投影三维测量的过程,在传统数字条纹投影三维测量技术条纹投影、相位计算、相位展开、相位深度映射的流程中,研究者们已经成功证明了前三个环节以及整个流程结合深度神经网络的可行性。基于深度学习,PDNet (Phase to Depth Network)神经网络模型被提出,用于绝对相位到深度的映射。结合多阶段深度学习单帧条纹投影三维测量方法,通过分阶段学习方式依次获得物体的绝对相位与深度信息。实验结果表明,PDNet能较准确地测量出物体的深度信息,深度学习应用于相位深度映射步骤具有可行性。并且,相较于直接从条纹图像到三维形貌的单阶段深度学习单帧条纹投影三维测量方法,多阶段深度学习单帧条纹投影三维测量方法可以明显提升测量精度,仅需单帧条纹图像输入即可获得毫米级测量精度,且能适应具有复杂形貌物体的三维测量。     

离轴抛物面镜像面扫描太赫兹光学设计

为了提高太赫兹成像速度,设计了一种像面扫描太赫兹快速成像系统。它为反射式单像素探测器成像,成像系统采用新设计的表面镀金的离轴抛物面镜结构以实现大口径、无遮拦、高反射率、高质量成像;反射成像系统光学设计F数为2.93,通光孔径为100 mm,视场为1,焦距为293.45 mm,成像窗尺寸为64 mm64 mm,圆孔直径为2 mm,扫描采集1616像素图像时间为0.1 min,3232像素图像时间为0.42 min,6464像素图像时间为1.7 min,空间分辨率为1 cm。扫描系统结合压缩传感成像理论采用新型像面扫描方法实现快速成像,在系统焦平面位置加入旋转多孔盘,对像面的图像进行太赫兹能量强度扫描,使用金属光锥收集能量到高莱探测器。利用压缩传感理论的特殊条件（采样数目与图像像素数相等）进行像面图像采集,然后利用正则归一化方程重构像面图像,该系统具有成像速度快、分辨率高、低成本、结构紧凑合理的优点。     

Silicon-based optoelectronic heterogeneous integration for optical interconnection

The performance of optical interconnection has improved dramatically in recent years. Silicon-based optoelectronic heterogeneous integration is the key enabler to achieve high performance optical interconnection, which not only provides the optical gain which is absent from native Si substrates and enables complete photonic functionalities on chip, but also improves the system performance through advanced heterogeneous integrated packaging. This paper reviews recent progress of silicon-based opt...     

基于单片机的小型气象台系统设计

文章针对各种环境问题对人们产生的不利影响,为了方便人们提前做好预防措施,设计了小型气象台系统。设计以单片机STC89C52为控制中心,运用相应的传感器完成对环境中温度、湿度、风速以及PM_2.5的数值采集,对模拟量进行A/D转换之后,通过无线传输模块传送数据,最后在LCD1602液晶显示屏完成数据显示。测试结果表明温度在-20℃～+60℃之间,湿度的数据在0.0%～99.99%之内,在有烟雾等细小颗粒存在的状况下,PM_2.5的值较大。     

Anomalous behavior and phase transformation of α-GaOOH nanocrystals under static compression

The structural compression mechanism and compressibility of gallium oxyhydroxide, α-GaOOH, are investigated by in situ synchrotron radiation x-ray diffraction at pressures up to 31.0 GPa by using the diamond anvil cell technique. Theα-GaOOH sustains its orthorhombic structure when the pressure is lower than 23.8 GPa. The compression is anisotropic under hydrostatic conditions, with the a-axis being most compressible. The compression proceeds mainly by shrinkage of the void channels formed by the coordination GaO_3(OH)_3 octahedra of the crystal structure. Anomaly is found in the compression behavior to occur at 14.6GPa, which is concomitant with the equatorial distortion of the GaO_3(OH)_3 octahedra. A kink occurs at 14.6 GPa in the plot of finite strain f versus normalized stress F, indicating the change in the bulk compression behavior. The fittings of a second order Birch–Murnaghan equation of state to the P–V data in different pressure ranges result in the bulk moduli B_0= 199(1) GPa for P 14.6 GPa and B_0= 167(2) GPa for P 14.6 GPa. As the pressure is increased to about 25.8 GPa, a first-order phase transformation takes place, which is evidenced by the abrupt decrease in the unit cell volume and b and c lattice parameters.