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Formation and migration of space charge packet in low density polyethylene

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Science china(Technological Sciences) 2005年第3期48卷 354-360页

作者： zheng Feihu 1., ZHANG Yewen 1., GONG Bin 1., {1. Jianwei 1.& WU Changshun 2.1. Pohl Institute of Solid State Physics, Tongji University, {1. 2.0092.{2. 2.{2. National Center for Quality Supervision and Test of Electric Ware and Cable, {1. 2.0093,{2. 1. Pohl Institute of Solid State Physics Tongji University 200092 Shanghai China 2. china National Center for Quality Supervision and Test of Electric Ware and Cable 200093 Shanghai China

Pressure wave propagation (PWP) method was utilized to observe the space charges packet-like behavior in sheet samples of low-density polyethylene (LDPE) under the relative low electric field. The experimental results show that space charge packets are always generated at the anode and move across the sample to the cathode regardless of the polarity of DC voltage. This paper discusses the migration of space charge packets at 30–40°C, the possible charge resource of space charge packets carriers and trap level of the space charge.

关键词： solid dielectric,low-density polyethylene,space charge packet,trap.

Construction of a genetic map and localization of QTLs for yield traits in tomato by SSR markers

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Progress in Natural Science:Materials International 2005年第9期15卷 793-797页

作者： LIU Yang 1.2., chen Huoying1.*, WEI Yutang2.and {1.ANG Tianming1.1. Department of Plant Science, {1. Jiaotong University, {1. 2.1.01. china 2. Department of Horticulture, Shenyang Agricultural University, Shenyang 1.01.1. china) Department of Plant Science Shanghai Jiaotong University Shanghai 201101 China. Department of Horticulture Shenyang Agricultural University Shenyang 110161 China

Using an F2.opulation derived from the hybrid of Lycopersicon esculentum Mill. ‘XF 98-7’× Lycopersicon pimpinellifolium LA2.0}4, a SSR genetic linkage map of tomato is constructed. The map contains 1.2.markers and spans 808.4 cM with an average distance of 7.2. cM between loci. Two quantitative trait loci （QTLs） for first flower node on chromosomes 5 and 1., two QTLs for number of flowers per truss on chromosomes 2.and 5, and five QTLs for fruit weight on chromosomes 1. 2. 3, 9 and 1. are identified.

关键词： tomato SSR markers genetic mapping first flower node number of flowers per truss fruit weight.

I-V and C-V properties of TiO_2.thin film by pulsed-laser reactive deposition

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Chinese Science Bulletin 1998年第16期43卷 1344-1349页

作者： FU zhengwen 1. ZHOU Mingfei 1. ZHANG Shengkun 2.{1. Lianyao 2.and QIN Qizong 1.1. Laser Chemistry Institute, Fudan University, {2. 2.0433, china 2. Department of Physics, Fudan University, {2. 2.0433, china Laser Chemistry Institute Fudan University Shanghai China Department of Pnysics Fudan University Shanghai China

TiO-2.thin films have bee deposited on p-Si(1.1. substrates by pulsed-laser ablation of metallic Ti target in the O-3 ambient. The current-voltage and capacitance-voltage of the Al/TiO-2.Si capacitors are measured. The results show that the dielectric constant of thin film after being annealed at 700℃ is found to be 46, and the border trap density and the interface state density at the TiO-2.p-Si interface are 1.8×1. 1. cm -2.and 2.1. 1. eV -1.cm -2. respectively. The conduction mechanisms of as-deposited films are also discussed.

关键词： TiO-2 dielectric properties electrical properties pulsed-laser deposition.

Experimental EOS determination of aluminum at Mbar pressure

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Science china(Physics,Mechanics & Astronomy) 2004年第4期47卷 416-423页

作者： chen Jianping1.2. LI Ruxin1. ZENG Zhinan1. WANG Xingtao1.& XU Zhizhan1.1. {1. Institute of Optics and Fine Mechanics, {1. 2.1.00, china 2. Beijing Aeronautical Technology Research Center, Beijing 1.0076, china 1. shanghai Institute of Optics and Fine Mechanics 201800 Shanghai China 2. Beijing Aeronautical Technology Research Center 100076 Beijing China

A shock wave is driven by a laser pulse of 1.2.ps duration (FWHM), with the intensity of ～1.1. W/cm2.at 785 nm, irradiating a 500 nm thick aluminum foil. A chirped laser pulse split from the main pulse is used to detect the shock breakout process at the rear surface of the target based on frequency domain interferometry. The mean shock velocity determination benefits from the precise synchronization (＜1.0fs resolution) of the shock pump and probe laser pulses, which is calculated from the time the shock takes to travel the 500 nm thick aluminum. The released particle velocity determination benefits from the chirped pulse frequency domain interferometry. The average shock velocity is 1..1. km/s and the shock release particle velocity is 1..2. km/s, and the corresponding pressure after shock is 3.1. Mbar under our experimental condition.

关键词： shock wave, equation of state, chirped laser pulse.

Transient species and its properties of melatonin

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Science china Chemistry 2006年第4期49卷 308-314页

作者： zhu Hongping1.2. ZHANG Zhaoxia1.2. ZHAO Hongwei1. WANG Wenfeng1.& YAO Side1.1. {1. Institute of Applied Physics, Chinese Academy of Sciences, {1. 2.1.00,{2. 2. Graduate University of the Chinese Academy of Sciences, Beijing 1.0049,{2. 1. shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China 2. Graduate University of the Chinese Academy of Sciences Beijing 100049 China

The photo-physical and photo-chemical properties of melatonin (ML) werestudied by 2.6 nm laser flash photolysis (LFP). ML undergoes photo-ionization to produce radicalcation of ML (ML^(·+))and hydrated electrons (e_(aq)^-), while excited triplet state ~3ML~* is alsoformed during photolysis. The oxidation via one electron transfer from ML to SO_4^(·+) and thetriplet state of riboflavin (~3RF~*) has been also investigated and the rate constants for theprocess have been determined to be 8.0x1.^9 and 1.4x1.^9 L·mol^(-1.·s^(-1. respectively. Theradical cation of 2.2.'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS^(·+)) scavengingcapacities of melatonin and other antioxidants are compared in this paper.

关键词： melatonin, laser flash photolysis, photoionization, triplet state.

Influence of Interpenetrating Polymer Networks (IPN) Microstructure on Underwater Acoustic Stealth Performance

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Journal of Wuhan University of Technology(Materials Science) 2010年第2期25卷 272-277页

作者：罗忠 College of Naval Architecture and Power Naval University of Engineering

According to the configuration and absorption theory of polymer macromolecule materials, a kind of IPN with wider temperature range and higher damping property was designed and synthesized. By using the spectrum of dynamic mechanical thermal analysis （DMTA） and acoustic pulse tube device, the microstructure, phase separation degree, phase size and phase continuity of IPN with different components were analyzed. The experimental results show that the nano size grade of phase, the continuous and homogeneous IPN phase can provide higher absorption coefficient. The absorption coefficient of optimized sample I09 is 0.7 in 2.kHz, and the absorption peak is 0.9 in 4 kHz. Then the underwater acoustic properties of modified IPN filled with mica, micro-balloon and nano-SiO2.were discussed respectively to indicate that the inhomogeneous property of filler-modified IPN can improve the underwater acoustic stealth performance effectively, and the micro size grade of these filler-modified IPN can work well in low frequency acoustic stealth.

关键词： interpenetrating polymer networks (IPN) polyurethane damping absorption coefficient fillers

New Exact Solutions to (2.1.-Dimensional Variable Coefficients Broer-Kaup Equations

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Communications in Theoretical Physics 2006年第9期46卷 393-396页

作者： zhu Jia-Min~(1.2.+) MA {1.-Yi~(1.2. ~1.Department of Physics, Zhejiang Lishui University, Lishui 32.000,{1. ~2.{2. Institute of Applied Mathematics and Mechanics, {2. 2.0072.{1. Department of Physics Zhejiang Lishui University shanghai Institute of Applied Mathematics and Mechanics

In this paper, using the variable coefficient generalized projected Ricatti equation expansion method, we present explicit solutions of the (2.1.-dimensional variable coefficients Broer-Kaup (VCBK) equations. These solutions include Weierstrass function solution, solitary wave solutions, soliton-like solutions and trigonometric function solutions. Among these solutions, some are found for the first time. Because of the three or four arbitrary functions, rich localized excitations can be found.

关键词： variable coefficient generalized projected Ricatti equation method (2.1.-dimensional variable coefficients Broer Kaup equations Weierstrass function solution solitary wave solution trigonometric function solution

Fredholm operators in Toeplitz algebras associated with discrete abelian groups

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Chinese Science Bulletin 1998年第14期43卷 1175-1179页

作者： XU Qingxiang 1.and chen Xiaoman 2.1. Department of Mathematics, {1. Normal University,{2., china 2. Laboratory of Mathematics for Nonlinear Sciences and Institute of Mathematics, Fudan University, {1. 2.0433, china Department of Mathematics Shanghai Normal University Shanghai China Laboratory of Mathematics for Nonlinear Sciences and Institute of Mathematics Fudan University Shanghai China

The locally finite below sets are introduced and the Fredholm operators in Toeplitz algebras associated with discrete abelian groups are studied.

关键词： discrete abelian group quasi_ordered group Toeplitz operator Fredholm operator.

Interdecadal variation of drought patterns and associated influencing factors in the north-south transitional zone of china

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Journal of Geographical Sciences 2024年第7期34卷 1253-1279页

作者： DONG Qingdong zhu Lianqi DUAN {1. WANG Liyuan {2. Chaonan LI Yanhong zhu Wenbo GURUNG Sher Bahadur The College of Geography and Environmental Science Henan UniversityKaifengHenan475004China Department of Physical Geography and Ecosystem Science Lund UniversityLundS-22362Sweden Central Department of Geography Tribhuvan UniversityKathmandu44600Nepal

In the context of global warming,escalating water cycles have led to a surge in drought frequency and ***,multidecadal fluctuations in drought and their multifaceted influencing factors remain inadequately *** study examined the multidecadal changes in drought characteristics(frequency,duration,and severity)and their geographical focal points within china's north-south transitional zone,the Qinling-Daba Mountains(QDM),from 1.60 to 2.1. using the Standardized Precipitation Evapotranspiration Index(SPEI).In addition,a suite of eight scenarios,correlation analysis,and wavelet coherence were used to identify the meteorological and circulation factors that influenced drought *** results indicate the following:(1.From 1.60 to 2.1.,the QDM experienced significant interdecadal variations in drought frequency,duration,and severity,the climate was relatively humid before the 1.90s,but drought intensified ***,the 1.90s marked the period of the longest drought duration and greatest severity,while the years spanning 2.1. to 2.1. experienced the highest frequency of drought events.(2.Spatially,the Qinling Mountains,particularly the western Qinling Mountain,exhibited higher drought frequency,duration,and severity than the Daba *** disparity can be attributed to higher rates of temperature increase and precipitation decrease in the western Qinling Mountain.(3)Interdecadal variations in droughts in the QDM were directly influenced by the synergistic effects of interdecadal fluctuations in air temperature and *** factors modulate temperature and precipitation through phase transitions,thereby affecting drought dynamics in the *** Atlantic Multidecadal Oscillation emerges as the primary circulation factors influencing temperature changes,with a mid-1.90s shift to a positive phase favoring *** East Asian Summer Monsoon and El Ni?o-Southern Oscillation are the main circulation factors a

关键词： drought standardized precipitation evapotranspiration index multidecadal shift transitional zone Qinling-Daba Mountains