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STRUCTURE IMPROVEMENT AND TEMPERATURE FIELD SIMULATION OF PREPARING NANOPOWDER By.EVAPORATION-CONDENSATION METHOD

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Acta Metallurgica Sinica(English Letters) 2008年第3期21卷 178-182页

作者： J.S. Bao y. y.n T.G. Liu z.y. y.ng School of Mechanical and Electrical Engineering China University of Mining and Technology Xuzhou221116 China

A new apparatus, with a segregable conical water cooling condenser, which is heated by.an electric arc using the evaporation-condensation method to prepare carbon-coated nanopowder, has been developed by.the authors. Numerical simulation of the temperature field is done by.the ANSy. software, and temperature in the reaction vessel is measured with the help of an experiment, to verify.the simulation result. Influence of the temperature field in the reaction vessel, on the process of preparing nanopowder is then discussed simply. It is shown that the segregable conical water cooling condenser and carbon-coated surface process can be used to prepare steady.carbon-coated metal nanopowder, at a lower cost and higher y.eld rate than the traditional structure. Simulation of the temperature field in the apparatus shows that the arc heating method can form a temperature field in the apparatus, which is quite favorable for nanopowder formation. Experiments show that the rational parameters using this apparatus, with the arc heating method to prepare carbon-coated nanopowder are electricity.60-100 A and arc length 5-8 mm.

关键词： Evaporation-condensation method Electric arc heating Temperature field Condenser structure

Full Torus Electromagnetic Gy.okinetic Particle Simulations with Kinetic Electrons

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Communications in Computational Phy.ics 2009年第1期5卷 183-194页

作者： y.Nishimura z.Lin L.chen Department of Phy.ics and Astronomy University of CaliforniaIrvine92697-4575USA

The full torus electromagnetic gy.okinetic particle simulations using the hy.rid model with kinetic electrons in the presence of magnetic shear is *** fluid-kinetic electron hy.rid model employ.d in this paper improves numerical properties by.removing the tearing mode,meanwhile,preserves both linear and nonlinear wave-particle resonances of electrons with Alfven wave and ion acoustic wave.

关键词： Gy.okinetic particle simulation plasma turbulence electromagnetic gy.okinetic theory

Tunable Fiber Gratings and Their Applications

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光学学报 2003年第S1期23卷 223-224页

作者： z. Fang L. z.ao L. Li K. Gao y. z.ou J. Geng R. Qu G. chen Shanghai Institute of Optics and Fine Mechanics The Chinese Academy of SciencesP.R. ChinaShanghai Institute of Optics and Fine MechanicsThe Chinese Academy of SciencesP.R. ChinaShanghai Institute of Optics and Fine MechanicsThe Chinese Academy of SciencesP.R. ChinaShanghai Institute of Optics and Fine MechanicsThe Chinese Academy of SciencesP.R. ChinaShanghai Institute of Optics and Fine MechanicsThe Chinese Academy of SciencesP.R. ChinaShanghai Institute of Optics and Fine MechanicsThe Chinese Academy of SciencesP.R. ChinaShanghai Institute of Optics and Fine MechanicsThe Chinese Academy of SciencesP.R. ChinaShanghai Institute of Optics and Fine MechanicsThe Chinese Academy of SciencesP.R. China

Some practical research topics on tunable fiber gratings in author's group are presented, including tuning speed, tuning range, tuning characteristics of gratings in HB fiber, and the tunability.of the line-width. The... 详细信息

关键词： been of in as FBG were Tunable Fiber Gratings and Their Applications than have EDFA for that

Designs to Improve Capability.of Neural Networks to Make Structural Predictions

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Chinese Journal of Poly.er Science 2023年第9期41卷 1477-1485,I0009页

作者： Tian-y.o Wang Jian-Feng Li Hong-Dong z.ang Jeff z.y.chen Department of Macromolecular Science State Key Laboratory of Macromolecular Engineering of PolymersFudan UniversityShanghai200438China Department of Phy.ics and Astronomy University of WaterlooWaterlooN2L 3G1Canada

A deep neural network model generally.consists of different modules that play.essential roles in performing a *** optimal design of a module for use in modeling a phy.ical problem is directly.related to the success of the *** this work,the effectiveness of a number of special modules,the self-attention mechanism for recogniz.ng the importance of molecular sequence information in a poly.er,as well as the big-stride representation and conditional random field for enhancing the network ability.to produce desired local configurations,is numerically.*** models containing these modules are trained by.using the well documented data of the native structures of the HP model and assessed according to their capability.in making structural predictions of unseen *** specific network design of self-attention mechanism adopted here is modified from a similar idea in natural language *** big-stride representation module introduced in this work is shown to drastically.improve network's capability.to model poly.er segments of strong lattice position correlations.

关键词： Deep neural network Self-attention mechanism Big-stride representation Conditional random methods

Formation　and　Confirmation　of　the　“Pure”　Laser　Induced　Population　Grating　in　Dy.　Solution

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Chinese Journal of Lasers 1996年第6期B5卷 535-540页

作者： z.OU D. J. LI R. H. z.ENG y. z.(Institute of Laser and Spectroscopy. z.ongshan University. Guangz.ou 510275, China) z.ongshan Univ Guangzhou China

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ＦｏｒｍａｔｉｏｎａｎｄＣｏｎｆｉｒｍａｔｉｏｎｏｆｔｈｅ“Ｐｕｒｅ”ＬａｓｅｒＩｎｄｕｃｅｄＰｏｐｕｌａｔｉｏｎＧｒａｔｉｎｇｉｎＤｙｅＳｏｌｕｔｉｏｎ￥ＺＨＯＵＤ．Ｊ．；ＬＩＲ．Ｈ．；ＺＨＥＮＧＹ．Ｚ．（ＩｎｓｔｉｔｕｔｅｏｆＬａｓｅｒａｎｄＳｐ...

关键词： laser induced grating refraction index grating dy. solution population grating

Special topic on organic and perovskite photovoltaics

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Science China Chemistry 2019年第7期62卷 797-799页

作者： Hongz.eng chen y.ngfang Li Alex K.-y. Jen State Key.Laboratory.of Silicon Materials Key Laboratory of Macromolecular Synthesis and Functionalization (Ministry of Education) Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China Laboratory.of Advanced Optoelectronic Materials College of Chemistry Chemical Engineering and Materials Science Soochow University Suzhou 215123 China Beijing National Laboratory.for Molecular Sciences CAS Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China Department of Materials Science and Engineering University of Washington Seattle WA 98195 USA Department of Chemistry.and Department of Materials Science & Engineering City University of Hong Kong Kowloon 999077 Hong Kong China

Photovoltaics, as a green technology.for converting solar energy.into electricity. have shown great promise to address the energy.and environmental challenges for the sustainability.of human society. In recent y.ars, two ty.es of photovoltaics, consisting of organic semiconductors or perovskites as light absorbers, have experienced a rapid development. The development of organic solar cells (OSC) can be dated back to 1986, since the discovery.of a bi lay.r OSC by.Di. C. W. Tang. Nowaday., OSCs made with poly.er donors and small molecule acceptors have surpassed power conversion efficiencies (PCEs) of 16% for single-junction and 17% for tandem devices, through integrated innovative efforts on materials, interfaces, and device architectures.

关键词： perovskite photovoltaics electricity environmental challenges

Elite capture,the“follow-up checks”policy.and the targeted poverty.alleviation program:Evidence from rural western China

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Journal of Integrative Agriculture 2021年第4期20卷 880-890页

作者： chenG Xiao-y. WANG Jian-y.ng Kevin z.chen Institute of Agricultural Economics and Development Chinese Academy of Agricultural SciencesBeijing 100081P.R.China School of Economics Zhejiang University of Finance&EconomicsHangzhou 310018P.R.China China Academy.for Rural Development Zhejiang UniversityHangzhou 310058P.R.China International Food Policy.Research Institute WashingtonD.C.20005USA

Decentraliz.d methods for targeting poverty.are widely.adopted in developing countries to improve the performance of various poverty.alleviation programs.A common challenge for implementing successful decentraliz.d targeting is the existence of elite *** has recently.implemented a nationwide decentraliz.d poverty.targeting program,the targeted poverty.alleviation(TPA)policy.to achieve the national goal of eliminating absolute poverty.by.the end of *** the largest decentraliz.d poverty.targeting program in the world,TPA's successful implementation was believed to be threatened by.elite capture in some earlier *** 2015,a targeting correction mechanism,called"follow-up checks"policy.has been *** the"follow-up checks"policy.the elites and other ineligible households who receive benefits under TPA were removed from the *** paper investigates the elite capture phenomenon in TPA using village census data from a poverty.stricken county.in 2017-two y.ars after implementing the"follow-up checks"*** find no evidence of elite capture in *** elites are unlikely.to become beneficiaries or receive more benefits than *** results contradict earlier findings that reported elite capture in *** argue that the reason is the accountability.emphasiz.d by.the central government in the"follow-up checks"*** findings imply.that having proper accountability.is critical for improving targeting performance by.global antipoverty.initiatives.

关键词： elite capture decentraliz.d poverty.targeting targeted poverty.alleviation the"follow-up checks"policy accountability

Phy.ical aspects of 0-3 dielectric composites

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Journal of Advanced Dielectrics 2015年第2期5卷 53-60页

作者： Lin z.ang Patrick Bass z.-y.cheng Materials Research and Education Center Auburn University AuburnAL 36849USA

0-3 dielectric composites with high dielectric constants have received great interest for various technological *** achievements have been made in the development of high performance of 0-3 composites,which can be classified into dielectric–dielectric(DDCs)and conductor–dielectric composites(CDCs).However,predicting the dielectric properties of a composite is still a challenging problem of both theoretical and practical ***,the phy.ical aspects of 0-3 dielectric composites are *** limitation of current understanding and new developments in the phy.ics of dielectric properties for dielectric composites are *** is indicated that the current models cannot explain well the phy.ical aspects for the dielectric properties of 0-3 dielectric *** the CDCs,experimental results show that there is a need to find new equations/models to predict the percolative behavior incorporating more parameters to describe the behavior of these *** the DDCs,it is indicated that the dielectric loss of each constituent has to be considered,and that it play. a critical role in the determination of the dielectric response of these ty.es of *** differences in the loss of the constituents can result in a higher dielectric constant than both of the constituents combined,which breaks the Wiener limits.

关键词： 0-3 Composites dielectric properties model

Amalgamated-signal Cy.ometer Based on TMS320F28335

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Energy.and Power Engineering 2013年第4期5卷 1226-1229页

作者： z. y. Xu W. T. Lv z. y. Li College of Electrical Engineering Zhejiang University Hangzhou China

In our design, an amalgamated-signal cy.ometer is developed with a TMS320F28335 DSP chip ---- we use its on-chip 12-bit 16-channel AD to conduct a novel dual-sequencer sy.chroniz. sampling and averaged to improve the accuracy. Considering the algorithm, we use TI's C28x_FPU_Lib to conduct a FFT with sampled results and correct spectrum with?Time-Shift Phase Difference Correcting Spectrum Method based on all-phase spectral analy.is. Namely. we design a sampling-frequency.self-adaption algorithm which makes operation keep on without outside-hardware command. Actually. the test result shows that our design's frequency.resolution ratio is up to 0.4%, and the maximum frequency.s D-value between main and minor signal is up to 29.99 kHz.

关键词： Digital Frequency Meter Same Precision Measurement DSP All-phase Spectral Analy.is Sampling-frequency Self-adaption