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微米纳米技术在空间技术中的应用研究

中国机械工程 2005年第z1期16卷 15-19页

作者：尤政李滨清华大学北京100084 清华大学北京100084

空间技术对MEMS技术的需求主要体现在两个方面:首先是探索以MEMS技术为代表的微米/纳米技术在航天领域的应用,这方面的研究更多地体现MEMS技术对航天领域的技术推动作用,其成果主要体现在研制若干适合于航天领域使用的MEMS器件;其次主要... 详细信息

空间技术对MEMS技术的需求主要体现在两个方面:首先是探索以MEMS技术为代表的微米/纳米技术在航天领域的应用,这方面的研究更多地体现MEMS技术对航天领域的技术推动作用,其成果主要体现在研制若干适合于航天领域使用的MEMS器件;其次主要以"虚拟卫星"和"网络卫星"为研究背景,介绍了采用一体化设计与系统集成的研究方法研制出的先进MEMS卫星.介绍了国内外微型航天器和MEMS的发展概况,重点分析了MEMS技术在微型航天器中的应用,指出了其发展前景,并介绍了目前我国在航天MEMS技术方面的研究情况.

关键词：微米纳米技术 MEMS 微型航天器编队飞行

Satellite Structure for Valence Shell of Methane by Electron Momentum Spectroscopy

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Chinese Physics Letters 1997年第11期14卷 827-829页

作者： FAN Xiao-wei ZHANG Qing-xiang ZHOU Shao-jie DENG Jing-kang zheng Yen-you CHEN Xue-jun Laboratory of Electron Momentum Spectroscopy Department of Modern Applied PhysicsTsinghua UniversityBeijing 100084 Department of Chemistry University of British ColumbiaCanada

The first extensive electron momentum spectroscopy study of the satellite structure in the inner valence region of methane at 1200eV is *** experimental momentum profiles belonging to the(2a_(1))^(-1) satellite state ... 详细信息

关键词： calculation. momentum Electron

N501Y mutation imparts cross-species transmission of SARS-CoV-2 to mice by enhancing receptor binding

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Signal Transduction and Targeted Therapy 2021年第8期6卷 2325-2327页

作者： Zubiao Niu zhengrong Zhang Xiaoyan Gao Peng Du Jingjing Lu Bohua Yan Chenxi Wang you zheng Hongyan Huang Qiang Sun Laboratory of Cell Engineering Institute of BiotechnologyResearch Unit of Cell Death MechanismChinese Academy of Medical Sciences2020RU009BeijingChina Department of Oncology Beijing Shijiton Hospital of Capital Medical UniversityBeijingChina

Dear Editor,According to the World Health Organization(WHO),as of March 8,2021,the pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)had infected more than 116 million patients with coronavirus disease 2019(COVID-19)(https://***).The high infectivity of SARS-CoV-2 is largely attributable to the unique sequence composition of its spike(S)glycoprotein.

关键词： acute respiratory glycoprotein

Identification and validation of heterotypic cell-in-cell structure as an adverse prognostic predictor for young patients of resectable pancreatic ductal adenocarcinoma

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Signal Transduction and Targeted Therapy 2020年第1期5卷 411-413页

作者： Hongyan Huang Meifang He Yanbin Zhang Bo Zhang Zubiao Niu you zheng Wen Li Peilin Cui Xiaoning Wang Qiang Sun Department of Oncology Beijing Shijitan Hospital of Capital Medical University10 Tieyi RoadBeijing 100038China Laboratory of General Surgery The First Affiliated HospitalSun Yat-Sen University58 Zhongshan 2nd RoadGuangzhou 510080China Laboratory of Cell Engineering Institute of Biotechnology20 Dongda StreetBeijing 100071China Department of Gastroenterology Beijing Tiantan Hospital of Capital Medical UniversityBeijing 100070China

Dear Editor,Pancreatic ductal adenocarcinoma(PDAC)has a poor prognosis,with an overall 5-year survival rate of less than 10%.Between 20 and 30%of PDAC cases are resectable at diagnosis;however,patients’post-operative survival periods vary widely,irrespective of active therapeutic interventions.1 Therefore,extensive efforts have been made to identify biomarkers that may identify patients with an improved *** profound local immune suppression had been implicated in PDAC progression and poor patient survival,a prognostic marker that can directly and functionally read immune evasion in situ is not yet available.

关键词： patients adenocarcinoma diagnosis

Research on dynamic performance of star tracker

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Instrumentation 2015年第1期2卷 17-26页

作者： SUN Ting XING Fei you zheng Department of Precision Instrument Tsinghua University State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua University Collaborative Innovation Center for Micro / Nano Fabrication Device and SystemTsinghua University

This manuscript briefly summarizes the development trends and recent research focus of the star *** the relevant technologies about dynamic performance of the star tracker are analyzed and *** can provide reference fo... 详细信息

关键词： Star tracker dynamic star image processing restoration of star image deep coupling

High Quantum Efficiency Back-Illuminated AlGaN-Based Solar-Blind Ultraviolet p-i-n Photodetectors

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Chinese Physics Letters 2012年第9期29卷 166-169页

作者： WANG Guo-Sheng LU Hai XIE Feng CHEN Dun-Jun REN Fang-Fang ZHANG Rong zheng you-Dou Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials and School of Electronic Science and EngineeringNanjing UniversityNanjing 210093

AlGaN-based back-illuminated solar-blind ultraviolet(UV)p–i–n photodetectors(PDs)with high quantum efficiency are fabricated on sapphire *** improve the overall performance of the PD,a series of structural design considerations and growth procedures are implemented in the epitaxy process.A distinct wavelength-selective photo-response peak of the PD is obtained in the solar-blind *** operating in photovoltaic mode,the PD exhibits a solar-blind/UV rejection ratio of up to 4 orders of magnitude and a peak responsivity of~113.5 mA/W at 270 nm,which corresponds to an external quantum efficiency of~52%.Under a reverse bias of-5 V,the PD shows a low dark current of~1.8 pA and an enhanced peak quantum efficiency of~64%.The thermal noise limited detectivity is estimated to be~3.3×10^(13) cm·Hz^(1/2)W^(-1).

关键词： AlGaN Efficiency sapphire

Electrical Activity of Frank Partial Dislocations and the influence of Metallic Impurities in Czochralski-Grown Silicon

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Chinese Physics Letters 1997年第6期14卷 436-439页

作者： SHEN Bo YANG Kai CHEN Peng ZHANG Rong SHI Yi zheng you-dou T.Sekiguchi K.Sumino Department of Physics Institute of Solid Solid State PhysicsNanjing UniversityNanjing 210093 Institute for Materials Research Tohoku UniversitySendai 980Japan

Electrical activity of Frank partial dislocations bounding stacking faults and the influence of Fe impurities in Czochralski-grown silicon are investigated by means of the electron-beam-induced-current(EBIC)*** partials free from metallic impurities exhibit EBIC contrast at low temperature but not at room temperature,indicating that they are only accompanied with shallow energy levels in the band *** energy level related to a Frank partial is determined to be about Ec-0.08eV in n-type *** partials decorated by Fe impurities become EBIC active at room temperature.

关键词： temperature. technique. Czochralski

The Effects of Polarization on the Current Transport Mechanisms for UV-LEDs

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Chinese Physics Letters 2013年第6期30卷 220-223页

作者： MA Ji-Zhao DONG Ke-Xiu CHEN Dun-Jun LU Hai CHEN Peng ZHANG Rong zheng you-Dou Key Laboratory of Advanced Photonic and Electronic Materials Nanjing National Laboratory of MicrostructureSchool of Electronics Science and EngineeringNanjing UniversityNanjing 210093

The effects of a polarization field on the current transport mechanisms in ultraviolet light emitting diodes(UV-LEDs)are studied by analyzing forward current-voltage(I–V)characteristics based on the experimental data and theoretical *** results indicate that polarization electric field suppresses the diffusion current and meanwhile enhances the tunneling current in the metal-face UV LEDs under forward *** presence of a large polarization field in the deep UV-LEDs is responsible for the current transport mechanism dominated by the tunneling process at a moderate forward bias.

关键词： polarization tunneling diodes

The Formation and Characterization of GaN Hexagonal Pyramids

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Chinese Physics Letters 2013年第5期30卷 116-119页

作者： ZHANG Shi-Ying XIU Xiang-Qian LIN Zeng-Qin HUA Xue-Mei XIE Zi-Li ZHANG Rong zheng you-Dou Key Laboratory of Advanced Photonic and Electronic Materials School of Electronic Science and EngineeringNanjing UniversityNanjing 210093

GaN with hexagonal pyramids is fabricated using the photo-assisted electroless chemical etching *** areas of the GaN substrate are selectively etched in a mixed solution of KOH and K2S2O8 under ultraviolet illumination,producing submicron-sized *** pyramids on the etched GaN with well-defined{1011}facets and very sharp tips are ***-resolution x-ray diffraction shows that etched GaN with pyramids has a higher crystal quality,and micro-Raman spectra reveal a tensile stress relaxation in GaN with pyramids compared with normal *** cathodoluminescence intensity of GaN after etching is significantly increased by three times,which is attributed to the reduction in the internal reflection,high-quality GaN with pyramids and the Bragg effect.

关键词： pyramid illumination ultraviolet