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Acta Metallurgica sinica(English Letters) 2009年第1期22卷 35-39页

作者： Jianbo YU Zhongming REN Weili REN Kang DENG Yunbo ZHONG Department of Materials Science and Engineering Shanghai University Shanghai 200072 China

The effects of electromagnetic vibration on the grain refinement in directional solid- ification were investigated. It was found that the electromagnetic vibration applied in the melt not only can refine grains remarkably but also can enhance both tensile strength and ductility values of Al-6%si alloy. SEM graphs show that coarse dendrite structure was broken up into a somewhat globular structure, and the morphology of eutectic silicon was changed from flaky to fibrous under electromagnetic vibration treatment. The refine mechanism under electromagnetic vibration was discussed.

关键词：电磁振动力学性能结构振动影响凝固过程合金 si 晶粒细化

Excess Carrier Lifetime Improvement in c-si Solar Cells by YAG:Ce^(3+)-Yb^(3+)

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Chinese Physics Letters 2016年第5期33卷 140-143页

作者： Talib Hussain 叶慧琪肖东 National Astronomical Observatories Nanjing Institute of Astronomical Optics &TechnologyKey Laboratory of Astronomical Optics & TechnologyNanjing Institute of Astronomical Optics&TechnologyChinese Academy of Sciences University of Chinese Academy of Sciences

Ce3＋-Yb3＋ doped Y3Al5O12 （YAG） is a luminescent down-conversion material which could convert visible pho- tons to near infrared photons. In this work, YAG：Ce3＋-Yb3＋ is applied on the front surface of mass-produced mono crystalline si solar cells. For the coated cells, the external quantum efficiencv from the visible to the near infrared is improved, and the energy conversion efficiency enhances from 11.70% to 12.2% under AMI.SG. Furthermore, the phosphor down-conversion effect on the solar cell is characterized by the microwave detected photoconductivity technique on the n-type silicon wafer under the 977nm excitation. The down-conversion materials improve the average excess carrier lifetime from 22.5μs to 24.2#s and the average surface recombi- nation velocity reduces from 424.Scm/s to 371.6cm/s, which reveal the significant reduction in excess carrier recombination by the phosphors.

关键词： by on Yb Excess Carrier Lifetime Improvement in c-si Solar Cells by YAG:Ce si YAG of in is down

Fully distributed certificateless threshold signature without random oracles

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Science China(Information Sciences) 2018年第9期61卷 259-269页

作者： Wenjie YANG Weiqi LUO Xizhao LUO Jian WENG Anjia YANG College of Cyber Security/College of Information Science and Technology Jinan University Guangdong Key Laboratory of Data Security and Privacy Preserving Guangzhou Key Laboratory of Data Security and Privacy Preserving School of Computer and Technology Soochow University

A certificateless(t,n)threshold signature(CLTS)scheme allows at least t members to cooperatively sign a message on behalf of an n-member group,which is a good way to share the responsibility and authority.Many researc... 详细信息

关键词： Fully distributed certificateless threshold signature without random oracles PKR si DKG CLS

Near-Range Large Field-of-View Three-Dimensional Photon-Counting Imaging with a single-Pixel si-Avalanche Photodiode

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Chinese Physics Letters 2018年第11期35卷 38-41页

作者：申光跃郑天翔杜秉乘吕阳武愕李召辉吴光 State Key Laboratory of Precision Spectroscopy East China Normal University Collaborative Innovation Center of Extreme Optics Shanxi University

Large field-of-view（FoV） three-dimensional（3 D） photon-counting imaging is demonstrated with a single-pixel single-photon detector based on a Geiger-mode si-avalanche photodiode. By removing the collecting lens（CL）before the detector, the FoV is expanded to ±10°. Thanks to the high detection efficiency, the signal-to-noise ratio of the imaging system is as high as 7.8 dB even without the CL when the average output laser pulse energy is about 0.45 pJ/pulse for imaging the targets at a distance of 5 m. A 3 D image overlaid with the reflectivity data is obtained according to the photon-counting time-of-flight measurement and the return photon intensity.

关键词： Near-Range Large Field-of-View Three-Dimensional Photon-Counting Imaging with a single-Pixel si-Avalanche Photodiode si

Illumination and Voltage Dependence of Electrical Characteristics of Au/0.03 Graphene-Doped PVA/n-si Structures via Capacitance/Conductance-Voltage Measurements

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Chinese Physics Letters 2015年第11期32卷 92-96页

作者： SAHAR Alialy AHMET Kaya I Uslua EMSETTIN Altmdal physics Department Faculty of Sciences Gazi University Ankara 06500 Turkey Opticianry Department Vocat Sch IVied Sci 7hrkey Turgut Ozal University Ankara 78050 Turkey Department of Chemistry Education Faculty of Education GazJ University Ankara 06500 Turkey

Au/n-si （MS） structures with a high dielectric interlayer （0.03 graphene-doped PVA） are fabricated to investigate the illumination and voltage effects on electrical and dielectric properties by using capacitance-voltage （C-V） and conductance-voltage （G/w-V） measurements at room temperature and at 1 MHz. Some of the main electrical parameters such as concentration of doping atoms （ND）, barrier height （ ФB（ C - V））, depletion layer width （WD） and series resistance （Rs） show fairly large illumination dispersion. The voltage-dependent profile of surface states （Nss） and resistance of the structure （Ri ） are also obtained by using the dark-illumination capacitance （Cdark- Cm） and Nicollian-Brews methods, respectively, For a clear observation of changes in electrical parameters with illumination, the values of ND, WD, ФB（O- V） and Rs are drawn as a function of illumination intensity. The values of ND and WD change almost linearly with illumination intensity. On the other hand, Rs decreases almost exponentially with increasing illumination intensity whereas ФB（C - V） increases. The experimental results suggest that the use of a high dielectric interlayer （0.03 graphene-doped PVA） considerably passivates or reduces the magnitude of the surface states. The large change or dispersion in main electrical parameters can be attributed to generation of electron-hole pairs in the junction under illumination and to a good light absorption. All of these experimental results confirm that the fabricated Au/0.03 graphene-doped PVA/n-si structure can be used as a photodiode or a capacitor in optoelectronic applications.

关键词： si PVA Illumination and Voltage Dependence of Electrical Characteristics of Au/0.03 Graphene-Doped PVA/n-si Structures via Capacitance/Conductance-Voltage Measurements

AN SQP ALGORITHM WITH NONMONOTONE LINE SEARCHFOR GENERAL NONLINEAR CONSTRAINED OPTIMIZATION PROBLEM

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Journal of Computational Mathematics 1997年第2期15卷 179-192页

作者： He, GP Diao, BQ Gao, ZY CHINESE ACAD SCI INST APPL MATHBEIJINGPEOPLES R CHINA SHANDONG INST MIN & TECHNOL SHANDONGPEOPLES R CHINA NO JIAOTONG UNIV BEIJINGPEOPLES R CHINA

In this paper, an SQP type algorithm with a new nonmonotone line search technique for general constrained optimization problems is presented. The new algorithm does not have to solve the second order correction subproblems for each iterations, but still can circumvent the so-called Maratos effect. The algorithm's global convergence and superlinear convergent rate have been proved. In addition, we can prove that, after a few iterations, correction subproblems need not be solved, so computation amount of the algorithm will be decreased much more. Numerical experiments show that the new algorithm is effective.

关键词： SQP si AN SQP ALGORITHM WITH NONMONOTONE LINE SEARCHFOR GENERAL NONLINEAR CONSTRAINED OPTIMIZATION PROBLEM Math LINE

Crystallization Behaviour of Laser Synthesized Nanometric Amorphous si_3N_4 Powders

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Journal of Materials Science & Technology 1995年第3期11卷 187-191页

作者： Yali LI Yong LIANG Zhuangqi HU(National Key Lab. of Rapidly Solidified Nonequilibrium Alloys, Institute of Metal Research,Chinese Academy of Sciences, Shenyang, 110015, China) Inst of Metal Research Chinese Acad of Sciences Shenyang China

The crystallization behaviour of the laser synthesized nanometric amorphous si3N4 powders with the particle size of 15 nm in diameter has been studied between 1200° and 1700℃ by XRD,TEM and FTIR techniques. A small amount of β-si3N4 formed at 1250℃ and increased slowly until the α- β transformation happened at 1700℃, whereas α-si3N4 appeared at 1300℃ andincreased rapidly between 1500-1600℃. The formation of β phase at the lower temperature was caused by the nitridation of free si due to the preexisted β-nuclei in the si3N4 particles, whereasthe α phase was formed by solid crystallization from the amorphous matrix. There were α and β siC formed at 1700℃ due to the presence of sio and Co gases in the system. FTIR analysis shows that two new IR absorption at 1356 and 1420 cm-1, and an overall strong absorption in wide wavenumber range resulted from the powders annealed at 1600 and 1700℃ respectively

关键词： si Am Crystallization Behaviour of Laser Synthesized Nanometric Amorphous si3N4 Powders OO

Relations among High-frequency Magnetic Properties and Frequency in Nanocrystalline Fe_(72.5)Cu_1Nb_2V_2si_(13.5)B_9 Alloy

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Journal of Materials Science & Technology 1999年第1期15卷 83-86页

作者： Yanzhong ZHANG(Major R & D Lab. for Functional Metal Materials, Research Centre, Shanghai Iron and Steel Research Institute,Shanghai 200940, China) Major R and D Lab. for Functional Metal Materials Research Centre Shanghai Iron and Steel Research Institute Shanghai 200940 China

High-frequency magnetic properties, such as core loss, coercivity and amplitude permeabilityof a newly-developed nanocrystalline Fe72.5Cu1Nb2V2si13.5B9 alloy in the wide ranges of f =20-103 kHz, Bm = 0.01~0.6 T and Bmf = 10~40 (T.kHz) have been measured. A largeamount of experimental data have been fitted by a computer, thus obtaining several expressionsrepresenting the influence of frequency on high-frequency magnetic properties, that are useful inpractical applications.

关键词： Cu1Nb2V2si B9 Alloy Relations among High-frequency Magnetic Properties and Frequency in Nanocrystalline Fe kHz Fe si

Effect of thermal shield and gas flow on thermal elastic stresses in 300mm silicon crystal

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Rare Metals 2006年第Z2期25卷 45-50页

作者： GAO Yu XIAO Qinghua ZHOU Qigang DAI Xiaolin TU Hailing General Research Institute for Nonferrous Metals Beijing 100088 China General Research Institute for Nonferrous Metals Beijing 100088 China General Research Institute for Nonferrous Metals Beijing 100088 China General Research Institute for Nonferrous Metals Beijing 100088 China General Research Institute for Nonferrous Metals Beijing 100088 China

The thermal elastic stresses induced in 300 mm si crystal may be great troubles because it can incur the generation of dislocations and undesirable excessive residual stresses. A special thermal modeling tool, CrysVUn, was used for numerical analysis of thermal elastic stresses and stress distribution of 300 mm si crystal under the consideration of different thermal shields and gas flow conditions. The adopted governing partial equations for stress calculation are Cauchy′s first and second laws of motion. It is demonstrated that the presence and shape of thermal shield, the gas pressure and velocity can strongly affect von Mises stress distribution in si crystal. With steep-wall shield, however, the maximal stress and ratio of high stress area are relatively low. With slope-wall shield or without shield, both maximal stress and ratio of high stress area are increased in evidence. Whether thermal shields are used or not, the increase of gas flow velocity could raise the stress level. In contrast, the increase of gas pressure cannot result in so significant effect. The influence of thermal shield and gas flow should be attributed to the modification of heat conduction and heat radiation by them.

关键词： thermal elastic stress simulation 300 mm si single crystal

Luminescent Properties of Tetrakis (1-(2-Thenoy)-3,3,3-Trifluoracetate) Europium N-Hexadecyl Pyridinium in Modified si-MCM-41

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Journal of Materials Science & Technology 2001年第2期17卷 290-292页

作者： Qinghong XU, Liansheng LI, Bin LI, Jihong YU and Ruren XU Key Laboratory of Inorganic Synthesis & Preparative Chemistry, Department of Chemistry, Jinn University, Changchun 130023, China Dept. of Chem. Jilin Univ. Changchun 130023 China

Eu(TTA)4C5H5NC16H33(TTA:1-(2-Thenoy)-3,3,3-Trifluoracetate) is encapsulated in St- MCM-41 modified with N-(3-Trimethoxysilethyl)ethylene. The emission spectrum of the assembly shows only a 5D0-7F2 transition. As compared with the rare earth complex itself, the lifetime of the assembly becomes longer and its stability under the UV radiation is much better.

关键词： MCM Europium N-Hexadecyl Pyridinium in Modified si-MCM-41 Trifluoracetate Thenoy si