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The technology for detection of gamma-ray burst with GECAm satellite

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Radiation Detection Technology and methods 2022年第1期6卷 12-25页

作者： x.Q.Li x.Y.Wen Z.H.An C.Cai Z.Chang G.Chen C.Chen Y.Y.Du m.gao R.gao K.Gong D.Y.Guo J.J.He D.J.Hou Y.G.Li C.Y.Li G.Li L.Li x.F.Li m.S.Li x.H.Liang x.J.Liu Y.Q.Liu F.J.Lu H.Lu B.meng W.x.Peng F.Shi x.L.Sun H.Wang J.Z.Wang Y.S.Wang H.Z.Wang x.Wen S.xiao S.L.xiong Y.B.xu Y.P.xu S.Yang J.W.Yang Q.B.Yi D.L.Zhang Fan Zhang S.N.Zhang C.Y.Zhang C.m.Zhang Fei Zhang x.Y.Zhao Y.Zhao x.Zhou C.S.Zhang J.P.Yu L.Chang K.K.Zhang J.Huang Y.m.Chen x.B.Han Institute of High Energy Physics CASBeijing 100049China xiangtan University Xiangtan 411105China Beijing Normal University Beijing 110875China Beijing Glass Research Institute Beijing 101100China Innovation Academy for microsatellites of CAS Shanghai 201204China

Introduction The main physical objective of the GECAm satellite is to detect gamma-ray bursts,which is related to gravitational waves of double compact object *** GECAm satellite also detects and investigates various bursts of high-energy celestial *** and methods In this study,we designed,developed and calibrated the payload and launched it into orbit with GECAm *** payload consists of the gamma ray detector(GRD,for detecting 4 keV–4 meV x/γray),the charged particle detector(CPD,for detecting 150 keV–5 meV charged particle),and the electronic box(EBOx).The all-sky field coverage is achieved via two 229-degree large-area satellites positioned 180 degrees apart and are on opposite sides of the *** satellite is equipped with 25 GRDs and 8 CPDs;thus,the satellite can identify charged particle bursts in ***-ray detectors adopt lanthanum bromide crystal technology combined with silicon *** is the first time that this technology was used massively in space *** The GECAm satellite can quickly determine the direction of gamma-ray bursts(positioning)via indexing and fitting method,while the transmit variability,energy spectrum and direction of the gamma-ray bursts guide subsequent observations through the Beidou-3 RDSS in quasi-real *** will play an important role in the study of high energy celestial bursts.

关键词： GECAm Gamma-ray burst Lanthanum bromide crystal Silicon photomultiplier Beidou short message

Fuzzy Clustering with the Structural α-Entropy

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Chinese Journal of Electronics 2018年第6期27卷 1118-1125页

作者： LI Kai gao Yan School of Cyber Security and Computer Hebei University

We study fuzzy clustering with the structural α-entropy and present a unified framework for fuzzy clustering with fuzzy entropy, which can be regarded fuzzy clustering with fuzzy entropy as its special case. Then,aiming at weighting exponent m equal to the structuralα-entropy index α in the presented unified framework, we obtain the fuzzy membership degrees and cluster centers using Lagrange method. Further, we propose the Structural α-entropy based fuzzy c-means(SEFCm) ***, to solve clustering of the complicated data, we also present the Structural α-entropy based kernel fuzzy c-means(SEKFCm) algorithm. In experiment, some University of California Irvine(UCI) data sets and synthetic data sets are used to test the performance of the presented algorithms and the role of the structural α-entropy. The experimental results show that the presented algorithms obtain better clustering result.

关键词： Structural α-entropy Unified framework Kernel function Fuzzy clustering Structural α-entropy based fuzzy c-means(SEFCm) algorithm Structural α-entropy based kernel fuzzy c-means(SEKFCm) algorithm

Improved blending strategy for membrane modification virtue of surface segregation using surface-tailored amphiphilic nanoparticles

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Frontiers of Environmental Science & Engineering 2016年第6期10卷 113-121页

作者： Shuai Liang Peng gao xiaoqi gao Kang xiao xia Huang College of Environmental Science and Engineering Beijing Forestry University Beijing 100083 China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100049 China State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Beijing 100084 China

membrane modification is one of the most feasible and effective solutions to membrane fouling proble.m which tenaciousl.y hampers .the furher au .gmentation of me .rnbrane *** *** modification with nanoparticles （NPs）, owing to the convenience of being incorporated in established ***. ction lines, possesses an advantag, eous viability in practical ***, the existing blending strategy suffers from a low utilization efficiency due to NP encasement by membrane matrix. The current study proposed an improved blending modification approach with amphiphilic NPs （aNPs）, which were prepared through silanization using 3-（Trimethoxysilyl）propyl methacrylate （TmSPmA） as coupling agents and ZnO or SiO2 as pristine NPs （pNPs）, *** Fourier transform infrared and x-ray photoelectron spectroscopy analyses revealed thepresence of appropriate organic components in both the ZnO and SiO2 aNPs, which verified the success of the silanization process. As compared with the pristine and conventional pNP-blended membranes, both the ZnO aNP-blended and SiO2 aNP-blended membranes with proper silanization （100% and 200% w/w） achieved a significantly increased blending efficiency with more NPs scattenng on the internal and external membrane surfaces under scanning electron microscope observation. This improvement contributed to the increase of membrane hydrophilicity. Nevertheless, an extra dosage of the TmSPmA led to an encasement of NPs, thereby adversely affecting the properties of the resultant membranes. On the basis of all the tests, 100% （w/w） was selected as the optimum TmSPmA dosage for blending modification for both the ZnO and SiO2 types.

关键词： membrane modification Nanoparticle Hydrophilic Amphiphilic Blending

A　STREAm-LINED　PROCEDURE　FOR　DETERmINATION　OF　STARCH,NON-STARCH　POLYSACCHARIDES　AND　FREE　SUGARS　IN　CEREALS

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Chinese Chemical Letters 1995年第9期6卷 791-794页

作者： Tian, FL Bai, T gao, AS Saren, C Choct, m Inner mongolia Univ Dept Chem Hohhot 010021 Peoples R China CSIRO Div Human Nutr Food Carbohydrates Lab Melbourne Vic Australia

Abstract: A stream - lined assay has beem developed for the determination of monosaccharides and oligosaccharides (free sugars), starch,soluble and insoluble non-starch polysaccharides of cereals and cereal products on a one-sample basis. After extraction of the free sugars with 80% ethanol,the sample is extracted in acetate buffer(pH 5. 0)with highyspecific(α-amylase and amyloglucosidase to degrade the starch,at the same time the non-starch polysaccharides (NSP) are fractioned into soluble and insoluble fractions. An aliquot from the supernatant containing the glucose released from starch is taken and analysed for starch using a glucose - oxidase/peroxidase method. The free sugars, soluble and insolubleNSP are then hydrolysed with acids and the released monosaccharides are reduced and acetylated. The resulting alditol acetates are accurately quantified using GC fitted with a capillary column in addition to accurately quantifying each ofthe monosaccharide constituents of the NSP,the procedure also gives accuratevalues for starch and free sugars.

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Quantum-inspired bacterial foraging algorithm for parameter adjustment in green cognitive radio

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Journal of Systems Engineering and Electronics 2015年第5期26卷 897-907页

作者： Hongyuan gao Chenwan Li School of Information and Communication Engineering Harbin Engineering University

Parameter adjustment that maximizes the energy efficiency of cognitive radio networks is studied in this paper where it can be investigated as a complex discrete optimization problem. Then a quantum-inspired bacterial foraging algorithm(QBFA)is proposed. Quantum computing has perfect characteristics so as to avoid local convergence and speed up the optimization of QBFA. A proof of convergence is also given for this *** superiority of QBFA is verified by simulations on three test functions. A novel parameter adjustment method based on QBFA is proposed for resource allocation of green cognitive radio. The proposed method can provide a globally optimal solution for parameter adjustment in green cognitive radio networks. Simulation results show the proposed method can reduce energy consumption effectively while satisfying different quality of service(Qo S)requirements.

关键词： green cognitive radio parameter adjustment quantum computing bacterial foraging algorithm

High resolution scanning optical imaging of a frozen planar polymer light-emitting electrochemical cell： an experimental and modelling study

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Science China Chemistry 2017年第4期60卷 497-503页

作者： Faleh AITal Jun gao Department of Physics Engineering Physics and Astronomy Queen's University Kingston Ontario K7L 3N6 Canada

Light-emitting electrochemical cells(LECs) are organic photonic devices based on a mixed electronic and ionic *** active layer of a polymer-based LEC consists of a luminescent polymer,an ion-solvating/transport polymer,and a compatible *** LEC p-n or p-i-n junction is ultimately responsible for the LEC *** LEC junction,however,is still poorly understood due to the difficulties of characterizing a dynamic-junction *** this paper,we present an experimental and modeling study of the LEC junction using scanning optical imaging *** LECs with an interelectrode spacing of 560μm have been fabricated,activated,frozen and scanned using a focused laser *** optical-beam-induced-current(OBIC)and photoluminescence(PL) data have been recorded as a function of beam *** OBIC profile has been simulated in COmSOL that allowed for the determination of the doping concentration and the depletion width of the LEC junction.

关键词： light-emitting electrochemical cell optical beam induced current frozen junction planar LECs polymer p-n junction

Simulation on scrap melting behavior and carbon diffusion under natural convection

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International Journal of minerals,metallurgy and materials 2021年第3期28卷 380-389页

作者： ming gao Jin-tao gao Yan-ling Zhang Shu-feng Yang State Key Laboratory of Advanced metallurgy University of Science and Technology BeijingBeijing 100083China School of metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

A 3D model applying temperature-and carbon concentration-dependent material properties was developed to describe the scrap melting behavior and carbon diffusion under natural *** results agreed reasonably well with experimental *** melting was subdivided into four stages:formation of a solidified layer,rapid melting of the solidified layer,carburization,and carburization+normal *** carburization stage could not be ignored at low temperature because the carburization time for the sample investigated was 214 s at 1573 K compared to 12 s at 1723 *** thickness of the boundary layer with significant concentration difference at 1573 K increased from 130μm at 5 s to 140μm at 60 *** maximum velocity caused by natural convection decreased from 0.029 m·s^(−1)at 5 s to 0.009 m·s^(−1)at 634 s because the differences in temperature and density between the molten metal and scrap decreased with time.

关键词： scrap melting natural convection carbon diffusion numerical simulation electron probe micro-analyzer

STUDY ON CRYOGENIC PHASE CHANGE & WEAR CHARACTERISTIC OF HIGH SPEED STEEL

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Acta metallurgica Sinica(English Letters) 2003年第6期16卷 524-530页

作者： m.C.Huang C.H.gao L.G.Huang DepartmentofmechanicalEngineering FuzhouUniversityFuzhou350002China HefeiUniversityofTechnology Hefei230009China

The microscopic structure change rule in high speed steel (HSS) after an additional cryogenic treatment was studied in this paper. Highly dispersed nano-carbide (η-Fe2 C) separated from tempering martensite was found distributed on twin planes of marten-site and dislocation places. Retained austenite was found sheared into martensite and nano-carbide separated at the same time. In addition, the tempering martensite was fine-grained. The stated changes of HSS evidently improve the lifespan of HSS cutter and fully show the advantages of nano-structure. The cryogenic treatment of HSS also improves the roughness of HSS cutter (decrease Ra number by about 50%) and greatly increases the wear resistance of HSS cutter. Further experiments on the wear characteristic of HSS cutter supported the findings mentioned above. The stated HSS treatment technology would implement nano-structure of traditional tool steel through phase change. It could be a new method to improve the performance of HSS cutter.

关键词： high speed steel cryogenic treatment phase change wear char-acteristic nano-structure

The current progress of PEmFC cold start models

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The current progress of PEMFC cold start models