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Diffusion Bonding of Tungsten to Copper and Its Alloy with Ti Foil and Ti/Ni/Ti Multiple Interlayers

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Journal of Materials Science & Technology 2003年第Z1期19卷 189-192页

作者： Guisheng ZOU Jun YANG Aaiping WU genghua huang Deku ZHANG Jialie REN Qing WANG Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

Ti foil and Ti/Ni/Ti multiple interlayers were selected for the bonding of tungsten to copper and CuCrZr *** of processing conditions on the microstructures and shear strength of the joints were *** Tifoil is used for bonding of tungsten to pure copper but not transformed into liquid solution during the holding time,the strength of the joints is relatively low because of the multiple compound layers with brittleness formed in thebonding *** strength of the joints increases significantly if the Ti foil is transformed into liquid solution and ismostly extruded out of the bonding *** same phenomena are found in the case when Ti/Ni/Ti multi-interlayersare used for bonding tungsten to CuCrZr alloy.

关键词： Tungsten Copper Multiple interlayers Diffusion bonding

Laser altimeter of CE-1 payloads system

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Science China(Physics,Mechanics & Astronomy) 2010年第10期53卷 1914-1920页

作者： WANG JianYu SHU Rong CHEN WeiBiao JIA JianJun WANG BingYong huang genghua HU YiHua HOU Xia Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai 200083China Shanghai Institute of Fine Optical Mechanical Chinese Academy of SciencesShanghai 201800China

The design and operation of the Laser Altimeter of CE-1 Payloads System are presented in this *** paper includes the design of the system and spacecraft-level laser,the description of the emitting-system and receiving system,and the testing of the laser *** CE-1 laser altimeter is the first Chinese deep-space probe using a *** has one beam and operates at 1 Hz,with a nominal accuracy of 5 *** laser altimeter has operated successfully in lunar orbit since November 28,*** has obtained 9120 thousand data values about the lunar altitude.

关键词： CE-1 orbiter laser altimeter system design

Cloud Detection and Centroid Extraction of Laser Footprint Image of GF-7 Satellite Laser Altimetry

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Journal of Geodesy and Geoinformation Science 2021年第3期4卷 1-12页

作者： Jiaqi YAO Guoyuan LI Jiyi CHEN genghua huang Xiongdan YANG Shuaitai ZHANG College of Geomatics Shandong University of Science and TechnologyQingdao 266590China Land Satellite Remote Sens-ing Application Center Ministry of Natural Resources of P.R.ChinaBeijing100048China Key Laboratory of Space Active Opto-electronics Technology Chinese Academy of SciencesShanghai200083China College of Mapping and Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China

The laser altimeter loaded on the GaoFen-7(GF-7)satellite is designed to record the full waveform data and footprint image,which can obtain high-precision elevation control points for stereo *** footprint camera equipped on the GF-7 laser altimetry system can capture the energy distribution at the time of laser emission and the image of the ground object where the laser falls,which can be used to judge whether the laser is affected by the *** the same time,the centroid of laser spot on the footprint image can be extracted to monitor the change of laser pointing *** this manuscript,a data quality analysis scheme of laser altimetry based on footprint image is ***,the cloud detection of footprint image is realized based on deep *** fusion result of the model is about 5%better than that of the traditional cloud detection algorithm,which can quickly and accurately determine whether the laser spot is affected by ***,according to the characteristics of footprint image,a threshold constrained ellipse fitting method for extracting the centroid of laser spot is proposed to monitor the pointing stability of long-period *** on the above method,the change of laser spot centroid since GF-7 satellite was put into operation is analyzed,and the conclusions obtained have certain reference significance for the quality control of satellite laser altimetry data and the analysis of pointing angle stability.

关键词： GF-7 quality control satellite laser altimetry laser footprint image cloud detection stability analysis of laser pointing angle

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空间激光测高技术发展及展望

红外与激光工程 2020年第11期49卷 1-10页

作者：舒嵘黄庚华孔伟中国科学院空间主动光电技术重点实验室上海200083 中国科学院上海技术物理研究所上海200083

空间激光测高技术通过在天基平台搭载脉冲激光测距仪,实现行星表面形貌信息获取,是开展对地和深空探测的重要手段。系统梳理了空间激光测高技术的发展历史和现状,提出应向多波束观测、近海及岛礁水下地形探测、激光主动多光谱探测这三... 详细信息

空间激光测高技术通过在天基平台搭载脉冲激光测距仪,实现行星表面形貌信息获取,是开展对地和深空探测的重要手段。系统梳理了空间激光测高技术的发展历史和现状,提出应向多波束观测、近海及岛礁水下地形探测、激光主动多光谱探测这三个方向发展,建议开展近红外波段单光子探测、超窄带光学滤波、多光子分辨探测、单光子数据星上预处理、高转换效率激光及非线性光频变换关键技术研究,促进我国空间激光测高技术的进一步发展。

关键词：激光测高激光雷达单光子探测多波束

Sequential-release of anticancer drugs microcapsulated with ethylcellulose

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中华医学杂志(英文版) 2002年第11期 129-131页

作者： GU genghua , huang Jianqi and HE Hong Department of Oral and Maxillofacial Surgery, the Second Affiliated Hospital, Zhejiang University, Hangzhou 310009, China (Gu GH, huang JQ and He H)

Objective To approach the sequential release of antitumor drugs and promote the effect of *** Adriamycin (ADM) and carboplatin (CBP) were respectively microcapsulated with ethylcellulose by organic phase separation. The morphology and sizes of the microcapsules were observed and measured with light microscope and scanning electromicroscope. The contents and the release rates of ADM and CBP in microcapsules were measured with fluorescence spectrophotometer and high-efficiency phantom chromatic (HPC) spectrum respectively. The antitumor sensitivity test in vitro was devised with MTT *** The microcapsules of ADM and CBP were spherical in shape with diameters of 196±64 μm and 214±48 μm respectively. The contents of one-layer and two-layer CBP and ADM microcapsules were 51.4%, 35.7% and 39.8% respectively, with the release rates in vitro of 62.4%/day, 54.8%/day and 48.2% /8h. The results of drug sensitivity test in vitro demonstrated that the current preparation has never affected the stability and antitumor activity of CBP and *** Microcapsules with different drugs and different thickness of material have different release rate. Combined arterial chemoembolization with different microcapsules could approach the sequential release and promote the effect of chemotherapy.

关键词： sequential release · microcapsule · adriamycin · carboplatin · ethylcellulose

“后精英”的社会印象:当代大学生对阶层分化及社会机会的主观认知

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浙江大学学报(人文社会科学版) 2013年第4期43卷 182-195页

作者：黄耿华莫家豪香港教育学院大中华研究中心

教育是影响社会流动的重要机制。在中国高等教育实行精英教育阶段,大学生群体能借助高考以"天之骄子"的身份快速跻身上层社会。20世纪90年代末,中国高等教育政策发生改变,由精英教育转向大众教育,使大学生群体由"天之骄子"变成"后精英"... 详细信息

教育是影响社会流动的重要机制。在中国高等教育实行精英教育阶段,大学生群体能借助高考以"天之骄子"的身份快速跻身上层社会。20世纪90年代末,中国高等教育政策发生改变,由精英教育转向大众教育,使大学生群体由"天之骄子"变成"后精英"。同时,在全面市场化改革的带动下,中国社会结构快速变迁,社会分层现象引人注目。调查结果显示,大学生群体倾向于认为社会分层已经"结构化",虽然较多的大学生对社会机会持乐观态度,但如若与精英教育时代的大学生相比,他们则认为"向上流动"的渠道已变得较为狭窄,且家庭背景及资源对一个人的前途发展有显性影响,代际"再生产"机制占据优势。虽然不同社会经济背景的大学生个体的看法存在差异,但从社会统计学的角度来看,整体认知的同质性较高。

关键词：社会机会社会分层社会流动大学生主观认识高等教育后精英

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光子计数激光测深系统

红外与激光工程 2019年第1期48卷 100-104页

作者：张河辉丁宇星黄庚华中国科学院上海技术物理研究所空间主动光电技术重点实验室上海200083 中国科学院大学北京100049

设计了一套基于光子计数探测体制的激光雷达水深探测系统,该系统工作波长为532 nm,单脉冲激光能量为0.5μJ,脉冲宽度为400 ps,激光重频为10 kHz,单光子探测器死时间为22 ns,时间间隔分辨率为50 ps。首先介绍了光子计数探测体制激光雷达... 详细信息

设计了一套基于光子计数探测体制的激光雷达水深探测系统,该系统工作波长为532 nm,单脉冲激光能量为0.5μJ,脉冲宽度为400 ps,激光重频为10 kHz,单光子探测器死时间为22 ns,时间间隔分辨率为50 ps。首先介绍了光子计数探测体制激光雷达用于水深探测的基本原理及其相对于传统机载激光测深雷达的优越性;然后分析了水底回波信号产生的平均光电子数与系统单脉冲激光能量的关系,从而理论求取出该系统的极限测深能力为3.7 m左右。最后进行了外场实地试验,对所获激光雷达点云数据进行滤波和解算,成功测得了透明盘深度为1.2 m的浑浊水体深度为2 m以内的水下信息。

关键词：激光雷达激光测深光子计数单光子

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单频激光干涉测振仪的非线性误差主动补偿法

激光与光电子学进展 2018年第8期55卷 313-320页

作者：张埔榛吴军黄庚华中国科学院大学北京100049 中国科学院上海技术物理研究所空间主动光电技术重点实验室上海200083

为了提高单频激光干涉测振系统的测量精度,提出了一种基于伪极值的非线性误差实时主动补偿方法,该方法使用伪极值计算直流偏置误差和不等幅误差,通过矢量相位校正运算抑制非正交误差。实验结果表明:该方法降低了测量期间因激光器功率漂... 详细信息

为了提高单频激光干涉测振系统的测量精度,提出了一种基于伪极值的非线性误差实时主动补偿方法,该方法使用伪极值计算直流偏置误差和不等幅误差,通过矢量相位校正运算抑制非正交误差。实验结果表明:该方法降低了测量期间因激光器功率漂移、Abbe误差导致的正交信号椭圆轨迹螺旋化形变,以及因数字信号传输误码造成的异常数据对非线性误差补偿的影响。在搭建的单频激光干涉测振系统中,使用伪极值法结合矢量相位校正运算方法可将周期性剩余误差峰峰值降低至0.8nm,比传统的极值法具有更好的非线性误差抑制效果,且该方法不需要复杂的运算,保持了良好的实时性。

关键词：测量单频激光干涉测振系统非线性误差补偿伪极值法纳米测量

用于大动态范围厘米精度激光测距的孔径光阑自动调整技术

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红外与激光工程 2013年第7期42卷 1788-1792页

作者：张冰娜黄庚华舒嵘王建宇中国科学院上海技术物理研究所空间主动光电技术与系统实验室上海200083

在深空或空间小目标的探测中,需要利用脉冲式激光雷达测量与目标之间的距离。当距离目标由几十千米到几十米范围变化时,探测器接收到的光通量动态范围达60 dB以上。要确保在整个量程范围内信号不饱和,需要采用复合型的自动增益控制技术... 详细信息

在深空或空间小目标的探测中,需要利用脉冲式激光雷达测量与目标之间的距离。当距离目标由几十千米到几十米范围变化时,探测器接收到的光通量动态范围达60 dB以上。要确保在整个量程范围内信号不饱和,需要采用复合型的自动增益控制技术。除了采用电子学的自动增益方法外,提出了一种自动调整接收光学通光口径的方式,通过对直流电机驱动的电动镜头光圈调整环的逐级调整,实现各级之间2倍光通量的变化。设计并实现了光圈、焦距、聚焦均由直流电机控制的电动镜头的驱动及控制电路,并搭建光路对孔径光阑进行标定,结果表明可以分为8级,且具有很好的重复性,使得全量程范围内准确度达厘米精度测距功能的实现成为可能。

关键词：深空探测激光主动探测高精度测距孔径光阑电动镜头