基于国产三代微光ICCD探测器的三维激光成像雷达

针对高分辨、高帧频激光三维视频成像问题,基于国产三代微光像增强器,采用线性增益调制单ICCD成像方法,建立激光发射功率和成像距离的数学模型、测距模型。考虑激光光源功率波动、脉宽误差、同能量脉冲误差因素,对三维成像测距误差进行分析,得出远距离高精度三维成像的解决措施。开展单ICCD增益调制激光三维成像雷达工程样机研制,并进行外场成像试验,结果表明该激光三维成像雷达具有25 Hz帧频、720×576高分辨率,220米外测距精度优于001m,实现对目标的三维成像,验证了分析与措施的有效性。     

Comparative studies of silicon photomultipliers and traditional vacuum photomultiplier tubes

Silicon photomultipliers (SiPMs) are a new generation of semiconductor-based photon counting devices with the merits of low weight, low power consumption and low voltage operation, promising to meet the needs of space particle physics experiments. In this paper, comparative studies of SiPMs and traditional vacuum photomultiplier tubes (PMTs) have been performed regarding the basic properties of dark currents, dark counts and excess noise factors. The intrinsic optical crosstalk effect of SiPMs was evaluated.     

非光气含氮化合物催化羰化研究进展

本文对近几年来非光气含氮化合物羰化合成氨基甲酸酯及二取代脲的方法进行了概述,主要包括使用钯、钌、铑、硒、金等催化体系以一氧化碳为羰化剂进行的催化氧化羰化和催化还原羰化反应过程,以及使用碱催化体系以二氧化碳和碳酸二甲酯等为羰化剂的反应过程和机理.     

Design and performance study of the LEPD silicon tracker onboard the CSES satellite

The low energy particle detector (LEPD) is one of the main payloads onboard the China seismic electromagnetic satellite (CSES). The detector is designed to ascertain space electrons (0.1-10 MeV) and protons (2-50 MeV). It has the capability of identifying the electrons and protons, to measure the energy spectrum and the incident angle of the particles. The LEPD is made up of a silicon tracker system, a CsI (Tl) mini-calorimeter, an anti-coincidence system made by plastic scintillator, as well as electronics and a data acquisition system (DAQ). The tracker is also a kind of E-E telescope; it consists of two layers of double-sided silicon strip detectors (DSSD). The signals emerging from the silicon tracker can be read out by two pieces of application specific integrated circuit (ASIC), which also can generate an event trigger for the LEPD. The functions of the DSSD system in the LEPD for charged particles were tested by 241Am @5.486 MeV α particles. The results show that the DSSD system works well, and has high performance to detect charged particles and measure the position of incident particles.     

利用Cherenkov光测量光电倍增管渡越时间涨落

采用符合方法,测量级联γ放射源⁶⁰Co在光电倍增管(PMT)光阴极窗上激发产生的切伦科夫光,从而测定PMT渡越时间涨落. 用泊松加高斯卷积方法获得单(多)光电子峰位,处理不同光电子数的~PMT~渡越时间涨落.测试XP2020和透紫XP2020Q PMT结果显示, 测量的渡越时间与菲利浦公司给出的指标一致, 渡越时间涨落与光电子数满足平方根反比关系. 该方法对可分辨单(多)光电子峰的~PMT~是可行的.     

微通道板电子输运特性的仿真研究

对微通道板(Micro-Channel Plate,MCP)的电子输运特性进行仿真研究.利用数值方法分析微光像增强器电子光学系统,得到电场分布.通过电场分布追踪MCP电子运动轨迹,确定电子在荧光屏像面上的落点分布.据此研究MCP电子输运,分析斜切角、通道直径及两端电压对电子输运、像增强器调制传递函数(Modulation Transfer Function,MTF)及分辨率的影响.结果显示,当MCP斜切角为14°、通道直径为5.0μm、两端电压为900 V时,MCP具有良好的电子输运特性,像增强器MTF特性好,分辨率高.     

A theoretical and experimental evaluation of III-nitride solar-blind UV photocathode

We have developed a superior solar-blind ultraviolet (UV) photocathode with an Al_xGa_1-xN photocathode (x ～ 0.45) in semi-transparent mode, and assessed spectra radiant sensitivity related to practical use. Before being grown over a basal plane sapphire substrate by low-pressure metal organic chemical vapor deposition (MOCVD), a reasonable design was made to the photocathode epitaxy structure, focusing on the Al_xGa_1-xN: Mg active layer, then followed by a comprehensive analysis of the structural and optical characterization. The spectra radiant sensitivity is peaked of 41.395 mA/W at wavelength 257 nm and then decreases by about 3 to 4 decades at 400 nm demonstrating the ability of this photocathode for solar-blind application prospects.     

超高效液相色谱-串联质谱法测定阿胶中马、牛、羊、猪、骆驼、鹿皮源成分

建立了阿胶中马、牛、羊、猪、骆驼、鹿皮源成分的检测方法。通过比对驴皮和马皮、牛皮、猪皮、羊皮、骆驼皮、鹿皮胶原蛋白的序列,采用蛋白酶切技术和高分辨质谱技术发现理论的各杂皮胶原蛋白特征肽。同时建立三重四极杆质谱筛查方法,以含0.1%（v/v）甲酸的乙腈溶液和0.1%（v/v）甲酸水溶液作为流动相,梯度洗脱,电喷雾离子源（ESI）正离子扫描模式,多反应监测。15批阿胶样品检出了杂皮源成分。该方法操作简便,专属性强,可用于阿胶中杂皮源成分的鉴别,并已成功用于阿胶日常打假监督抽验工作。