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Science china chemistry 2010年第3期53卷 519-527页

作者： zhang yu1,2,sun peijian1,2 & gan zhihua1 1cas key laboratory of engineering plastics,institute of chemistry,chinese academy of sciences,beijing 100190,china 2Graduate University of chinese academy of sciences,beijing 100039,china cas key laboratory of engineering plastics Institute of Chemistry Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

A series of controllable amphiphilic block copolymers composed of poly(ethylene oxide)(PEO) as the hydrophilic block and poly(ε-caprolactone)(PCL) as the hydrophobic block with the amino terminal group at the end of the PEO chain(PCL-b-PEO-NH2) were *** on the further reaction of reactive amino groups,diblock copolymers with functional carboxyl groups(PCL-b-PEO-COOH) and functional compounds RGD(PCL-b-PEO-RGD) as well as the triblock copolymers with thermosensitive PNIPAAm blocks(PCL-b-PEO-b-PNIPAAM) were *** well-controlled structures of these copolymers with functional groups and blocks were characterized by gel permeation chromatography(GPC) and 1H NMR *** copolymers with functionalized hydrophilic blocks were fabricated into microspheres for the examination of biofunctions via cell culture experiments and in vitro drug *** results indicated the significance of introducing functional groups(e.g.,NH2,COOH and RGD) into the end of the hydrophilic block of amphiphilic block copolymers for biomedical potentials in tissue engineering and controlled drug release.

关键词： amphiphilic block copolymers biodegradable polymers functional terminal group cell growth drug release

Analysis of junction temperatures in high-power gan-based LEDs

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Science china(Technological sciences) 2010年第2期53卷 297-300页

作者： JIANG yuXuan1, LI Zheng1, sun YongJian1, yu TongJun1, CHEN ZhiZhong1, zhang GuoYi1, zhang GuangChen2 & FENG ShiWei2 1 State key laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, beijing 100871, china 2 School of Electronic Information & Control engineering, beijing University of Technology, beijing 100124, china State key laboratory of Artificial Microstructure and Mesoscopic Physics School of Physics Peking University

We presented the analysis of the incomplete conduction in bonding medium in high power gan-based light-emitting diode (LED) packages. A numerical study was carried out with parametric model to understand the junction temperature variation due to bonding medium defects. Transient thermal measurement was performed to evaluate LED’s junction temperature. Thermal resistance from chip to lead frame was 20 K/W in our sample LED. It was suggested that only 60% of the surface area of the bonding medium was involved in the thermal conduction. This result was also supported by the SEM image. Blocking of thermal path induced by ineffective area of the bonding medium was regarded as a factor of its thermal resistance. Thus, the effective area of the bonding medium should be included in the FEM model and considered as another important factor in high power LED’s thermal management.

关键词： junction temperature bonding medium FEM simulation effective area

QCM and SPR Investigations on Enzymatic Degradation of Poly（ε-caprolactone） Film

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QCM and SPR Investigations on Enzymatic Degradation of Poly...

A seismic elastic moduli module for the measurements of low-frequency wave dispersion and attenuation of fluid-saturated rocks under different pressures

第三届工程塑料国际学术研讨会

作者： Yi Hou 1 Jing Chen 1 peijian sun 2 zhihua gan 2 Guangzhao zhang1 1. Hefei National laboratory for Physical sciences at Microscale Department of Chemical Physics University of Science and Technology of china Hefei Anhui china 2. cas key Laboraotry of engineering plastics institute of chemistry chinese academy of sciences (cas) beijing100080 china

The enzymatic degradation of poly（ε-caprolactone）（PCL） has been investigated by using quartz crystal microbalance with dissipation （QCM-D） and surface plasmon resonance （SPR） in situ. The frequency and dissipation responses of QCM-D and the SPR signal responses can well describe the weight loss and the morphological changes of a PCL film. Our experiments reveal that the degradation has much dependence on the crystallinity and morphology of PCL. PCL with lower crystallinity （45%） and small spherulites degrades in a way of layer-by-layer. Both QCM-D and SPR measurements demonstrate the degradation is of first-order. However, PCL with higher crystallinity （55%） and larger spherulites exhibits a more complex degradation behavior;namely, the degradation in crystalline region lags behind that in amorphous region, leading to a microporous structure.

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Petroleum Science 2024年第1期21卷 162-181页

作者： Yan-Xiao He Shang-Xu Wang Gen-Yang Tang Chao sun Hong-Bing Li San-Yi yuan Xian Wei Li-Deng gan Xiao-Feng Dai Qiang Ge Peng-Peng Wei Hui-Qing zhang National key laboratory of Petroleum Resources and engineering CNPC Key Lab of Geophysical ExplorationCollege of GeophysicsChina University of Petroleum(Beijing)Beijing102249China School of Resources and Geosciences China University of Mining and TechnologyXuzhou221116JiangsuChina Research institute of Petroleum Exploration and Development CNPCBeijing100083China beijing Vocational College of Labour and Social Security Beijing100029China Petrochina Dagang Oilfield Exploration and Development Research institute CNPCTianjin300280China

Knowledge about the seismic elastic modulus dispersion,and associated attenuation,in fluid-saturated rocks is essential for better interpretation of seismic observations taken as part of hydrocarbon identification and time-lapse seismic surveillance of both conventional and unconventional reservoir and overburden performances.A Seismic Elastic Moduli Module has been developed,based on the forced-oscillations method,to experimentally investigate the frequency dependence of Young's modulus and Poisson's ratio,as well as the inferred attenuation,of cylindrical samples under different confining pressure *** with three standard samples showed that the measured elastic moduli were consistent with the published data,indicating that the new apparatus can operate reliably over a wide frequency range of f∈[1-2000,10^(6)]*** Young's modulus and Poisson's ratio of the shale and the tight sandstone samples were measured under axial stress oscillations to assess the frequency-and pressure-dependent *** dry condition,both samples appear to be nearly frequency independent,with weak pressure dependence for the shale and significant pressure dependence for the *** particular,it was found that the tight sandstone with complex pore microstructure exhibited apparent dispersion and attenuation under brine or glycerin saturation conditions,the levels of which were strongly influenced by the increased effective *** addition,the measured Young's moduli results were compared with the theoretical predictions from a scaled poroelastic model with a reasonably good agreement,revealing that the combined fluid flow mechanisms at both mesoscopic and microscopic scales possibly responsible for the measured dispersion.

关键词： Low-frequency measurements Dispersion and attenuation Rock physics Fluid flow

Photonics-assisted THz wireless communication enabled by wide-bandwidth packaged backilluminated modified uni-traveling-carrier photodiode

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Opto-Electronic Science 2024年第7期3卷 20-29页

作者： yuxin Tian Boyu Dong Yaxuan Li Bing Xiong Junwen zhang Changzheng sun Zhibiao Hao Jian Wang Lai Wang Yanjun Han Hongtao Li Lin gan Nan Chi Yi Luo beijing National Research Center for Information Science and Technology(BNRist) Department of Electronic EngineeringTsinghua UniversityBeijing 100084China key laboratory of Information Science of Electromagnetic Waves(MoE) Department of Communication Science and EngineeringFudan UniversityShanghai 200433China Flexible Intelligent Optoelectronic Device and Technology Center Institute of Flexible Electronics Technology of THUJiaxing 314000China

This paper presents a wide-bandwidth back-illuminated modified uni-traveling-carrier photodiode(MUTC-PD)packaged with standard WR-5 rectangular waveguide for high-speed wireless *** optimized epitaxy structure and coplanar waveguide electrodes,the fabricated 4-μm-diameter PD exhibits ultra-flat frequency response and high saturation *** passive circuits including low-loss bias-tee and E-plane probe are designed to package the PD into a compact module with waveguide *** packaged PD module has demonstrated a flat frequency response with fluctuations within±2.75 d B over a broadband of 140–220 GHz and a high saturated output power of-7.8 d Bm(166μW)at 140 *** wireless communication applications,the packaged PD is used to implement 1-m free space transmission at carrier frequencies of 150.5 and 210.5 GHz,with transmission rates of 75 and 90 Gbps,respectively.

关键词： modified uni-traveling-carrier photodiode integrated bias-tee E-plane probe flat frequency response high saturation power WR-5 output THz wireless communications

Analysis of junction temperatures in high-power gan-based LEDs

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中国科学:技术科学 2010年第2期 199-199页

作者： JIANG yuXuan1, LI Zheng1, sun YongJian1, yu TongJun1*, CHEN ZhiZhong1, zhang GuoYi1, zhang GuangChen2 & FENG ShiWei2 1 State key laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, beijing 100871, china 2 School of Electronic Information & Control engineering, beijing University of Technology, beijing 100124, china

We presented the analysis of the incomplete conduction in bonding medium in high power gan-based light-emitting diode (LED) packages. A numerical study was carried out with parametric model to understand the junction temperature variation due to bonding medium defects. Transient thermal measurement was performed to evaluate LED's junction temperature. Thermal resistance from chip to lead frame was 20 K/W in our sample LED. It was suggested that only 60% of the surface area of the bonding medium was involved in the thermal conduction. This result was also supported by the SEM image. Blocking of thermal path induced by ineffective area of the bonding medium was regarded as a factor of its thermal resistance. Thus, the effective area of the bonding medium should be included in the FEM model and considered as another important factor in high power LED's thermal management.

关键词： junction temperature bonding medium FEM simulation effective area

Interface engineering of plasmonic induced Fe/N/C-F catalyst with enhanced oxygen catalysis performance for fuel cells application

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Nano Research 2022年第3期15卷 2138-2146页

作者： Xue Yin Ligang Feng Wen Yang yuanxi zhang Haiyan Wu Le Yang Lei Zhou Lin gan Shaorui sun key laboratory of Cluster Science of Ministry of Education Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China School of chemistry and Chemical engineering Yangzhou UniversityYangzhou 225002China institute of Materials Research Shenzhen Geim Graphene CenterTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China beijing key laboratory for Green Catalysis and Separation College of Environmental and Energy EngineeringBeijing University of TechnologyBeijing 100124China

The low intrinsic activity of Fe/N/C oxygen catalysts restricts their commercial application in the fuel cells technique;herein,we demonstrated the interface engineering of plasmonic induced Fe/N/C-F catalyst with primarily enhanced oxygen reduction performance for fuel cells *** strong interaction between F and Fe-N4 active sites modifies the catalyst interfacial properties as revealed by X-ray absorption structure spectrum and density functional theory calculations,which changes the electronic structure of Fe-N active site resulting from more atoms around the active site participating in the reaction as well as super-hydrophobicity from C–F covalent *** hybrid contribution from active sites and carbon support is proposed to optimize the three-phase microenvironment efficiently in the catalysis electrode,thereby facilitating efficient oxygen reduction *** catalytic performance for oxygen reduction and fuel cells practical application catalyzed by Fe/N/C-F catalyst is thus verified,which offers a novel catalyst system for fuel cells technique.

关键词： interface engineering Fe/N/C catalyst CF_(4)plasma treatment three-phase microenvironment proton exchange membrane fuel cells

CEPC Technical Design Report

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Radiation Detection Technology and Methods 2024年第1期8卷 I0003-I0016,1-1091页

作者： Waleed Abdallah Tiago Carlos Adorno de Freitas Konstantin Afanaciev Shakeel Ahmad Ijaz Ahmed Xiaocong Ai Abid Aleem Wolfgang Altmannshofer Fabio Alves Weiming An Rui An Daniele Paolo Anderle Stefan Antusch Yasuo Arai Andrej Arbuzov Abdesslam Arhrib Mustafa Ashry Sha Bai yu Bai Yang Bai Vipul Bairathi Csaba Balazs Philip Bambade Yong Ban Tripamo Bandyopadhyay Shou-Shan Bao Desmond P.Barber Ayse Bat Varvara Batozskaya Subash Chandra Behera Alexander Belyaev Michele Bertucci Xiao-Jun Bi yuanjie Bi Tianjian Bian Fabrizio Bianchi Thomas Biekotter Michela Biglietti Shalva Bilanishvili Deng Binglin Denis Bodrov Anton Bogomyagkov Serge Bondarenko Stewart Boogert Maarten Boonekamp Marcello Borri Angelo Bosotti Vincent Boudry Mohammed Boukidi Igor Boyko Ivanka Bozovic Giuseppe Bozzi Jean-Claude Brient Anastasiia Budzinskaya Masroor Bukhari Vladimir Bytev Giacomo Cacciapaglia Hua Cai Wenyong Cai Wujun Cai Yijian Cai Yizhou Cai yuchen Cai Haiying Cai Huacheng Cai Lorenzo Calibbi Junsong Cang Guofu Cao Jianshe Cao Antoine Chance Xuejun Chang yue Chang Zhe Chang Xinyuan Chang Wei Chao Auttakit Chatrabhuti Yimin Che yuzhi Che Bin Chen Danping Chen Fuqing Chen Fusan Chen gang Chen Guoming Chen Hua-Xing Chen Huirun Chen Jinhui Chen Ji-yuan Chen Kai Chen Mali Chen Mingjun Chen Mingshui Chen Ning Chen Shanhong Chen Shanzhen Chen Shao-Long Chen Shaomin Chen Shiqiang Chen Tianlu Chen Wei Chen Xiang Chen Xiaoyu Chen Xin Chen Xun Chen Xurong Chen Ye Chen Ying Chen yukai Chen Zelin Chen Zilin Chen gang Chen Boping Chen Chunhui Chen Hok Chuen Cheng Huajie Cheng Shan Cheng Tongguang Cheng yunlong Chi Pietro Chimenti Wen Han Chiu Guk Cho Ming-Chung Chu Xiaotong Chu Ziliang Chu Guglielmo Coloretti Andreas Crivellin Hanhua Cui Xiaohao Cui Zhaoyuan Cui Brunella D'Anzi Ling-yun Dai Xinchen Dai Xuwen Dai Antonio De Maria Nicola De Filippis Christophe De La Taille Francesca De Mori Chiara De Sio Elisa Del Core Shuangxue Deng Wei-Tian Deng Zhi Deng Ziyan Deng Bhupal Dev Tang Dewen Biagio Di Micco Ran Ding Siqin Dingl Yadong Ding Haiyi Dong Jianin AGH University of Science and Technology Faculty of Physics and Applied Computer ScienceKrakow Anhui University HefeiAnhui Applied Physics Department Federal Urdu University of ArtsScience and TechnologyIslamabad Banaras Hindu University Institute of ScienceVaranasi Bandirma Onyedi Eylul University Bandirma Beihang University Beijing beijing Computational Science Research Center Beijing beijing Conveyi LTD Beijing beijing Glass Research institute Co. LtdBeijing beijing institute of Technology Beijing beijing Normal University Beijing Brown University ProvidenceRI Budker institute of Nuclear Physics Novosibirsk Cadi Ayyad University Laboratory of Fundamental and Applied PhysicsPolydisciplinary FacultyMarrakech Cairo University Giza Center for Theory and Computation National Tsing Hua UniversityHsinchu Central china Normal University WuhanHubei Central South University ChangshaHunan Centro de Fisica Teorica de Particulas Universidade Tecnica de LisboaLisboa Chengdu KaitengSifang Digital Radio&TV Equipment Co. LtdChengduSichuan china academy of engineering physics MianyangSichuan china building materials academy Beijing china Center of Advanced Science and Technology Beijing china institute of Atomic Energy Beijing china Jiliang University HangzhouZhejiang china Nuclear Instrument CO. LTDBeijing china University of Geosciences Beijing china University of Geosciences WuhanHubei china University of Mining and Technology XuzhouJiangsu china West Normal University NanchongSichuan Chongqing University Department of PhysicsChongqing Chulalongkorn University Bangkok City University of Hong Kong Department of PhysicsHong Kong Cockcroft institute Daresbury Cornell University IthacaNY CPPM(AMU/IPhU&CNRS/INP) Marseille Dalian Minzu University DalianLiaoning Dalian University of Technology Department of PhysicsDalian Deutsches Elektronen-Synchrotron DESY Hamburg Dzhelepov laboratory of Nuclear Problems of Joint institute for Nuclear Research(DLNP JINR) Dubna East china University Of Science And Technol

The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by china,fostered through extensive collaboration with international *** complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs *** its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs *** the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of *** Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering ***,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection *** is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 *** commencement of experiments and data collection could potentially be initiated in the mid-2030s.

关键词： initiated exceeding precise

Graded composition and doping p-i-n Al_(x)Ga_(1−x)As/GaAs detector for unbiased voltage operation

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Nuclear Science and Techniques 2022年第7期33卷 73-82页

作者： Zhi-Fu Zhu Ji-Jun Zou Zhi-Jia sun He Huang Qing-Lei Xiu Zhong-Ming zhang Yong gan Chen-Xian Guo Shao-Tang Wang Xiu-Ping yue Guo-Li Kong School of Information engineering Zhengzhou University of TechnologyZhengzhou450044China engineering Research Center of Nuclear Technology Application(East china University of Technology) Ministry of EducationNanchang330013China State key laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China engineering Department LA14YWLancaster UniversityLancasterUK

p-i-n Al_(x)Ga_(1−x)As/GaAs detectors with graded compositions and graded doping were grown and *** the current-voltage and capacitance-voltage measurement results,the devices had good p-n junction diode characteristics,and the electric field strength under an unbiased voltage was 1.7×10^(5) Vcm^(-1).The full width at half maximum and charge collection efficiency of the detectors obtained from energy spectrum measurements of 5.48-MeV alpha particles were 3.04 and approximately 93%,*** this study,we created the most advanced and promising state-of-the-art unbiased detector reported to date.

关键词： Graded composition Graded doping Detector p-i-n Al_(x)Ga_(1−x)As/GaAs

基于Algan/gan HEMT外差探测器的太赫兹线阵列矢量探测系统

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红外与激光工程 2024年第6期53卷 166-175页

作者：王凯出丁青峰周奇蔡昕航张金峰朱凯强翟振钧孙厚军王林军秦华上海大学材料科学与工程学院上海200444 中国科学院苏州纳米技术与纳米仿生研究所中国科学院纳米器件与应用重点实验室江苏苏州215123 上海科技大学物质科学与技术学院上海201210 中国科学技术大学纳米技术与纳米仿生学院安徽合肥230026 北京理工大学集成电路与电子学院北京100081

为了研究Algan/gan高电子迁移率晶体管(High-Electron-Mobility Transistor,HEMT)外差探测器应用于太赫兹来波方向(Direction of Arrival,DOA)估计领域的可行性及量化性能指标,基于Algan/gan HEMT 243GHz外差探测器搭建了太赫兹波线阵列矢量探测系统,实现了太赫兹连续波的相位分布和来波方向的测量。该系统的核心器件为准光-波导耦合的太赫兹外差探测器线阵列组件,阵元平均噪声等效功率(Noise-Equivalent-Power,NEP)为-123.89dBm/Hz。通过测试,表明该系统相位解析稳定度优于0.6°,线阵列组件法线(阵列芯片的垂线)方向左右11°以内的太赫兹来波方向的检测误差小于0.25°。讨论了存在误差的原因及可能的解决方案,为后续基于Algan/gan HEMT面阵列的太赫兹相控阵雷达及定向通信系统的研制提供了基础。

关键词：太赫兹来波方向(DOA)估计阵列混频器外差(相干)探测氮化镓HEMT