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球对称动态黑洞的量子能层效应 被引量:11
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作者 黎忠恒 米丽琴 《物理学报》 SCIE EI CAS CSCD 北大核心 1999年第4期575-580,共6页
用NewmanPenrose形式,研究了球对称动态时空中的引力、电磁、标量和Dirac场,表明量子能层会影响动态黑洞的辐射机制.与Ker能层和电磁势产生的经典效应不同,这个效应的特征是辐射机制明显依赖于自旋态.
关键词 量子能层效应 黑洞 球对称 动态
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二维动态对称黑洞及标量场的热辐射
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作者 黎忠恒 赵峥 《北京师范大学学报(自然科学版)》 CAS CSCD 1995年第1期57-62,共6页
分别研究了用Eddington-Finkelstein时间v和普通时间t描述的二维动态时空中的对称黑洞,得到了局部事件视界、温度和标量场的热谱.用t描述的动态对称黑洞有奇特的结构,它的局部视界个数是对应静态黑洞的2倍... 分别研究了用Eddington-Finkelstein时间v和普通时间t描述的二维动态时空中的对称黑洞,得到了局部事件视界、温度和标量场的热谱.用t描述的动态对称黑洞有奇特的结构,它的局部视界个数是对应静态黑洞的2倍,有理由推测最外面的2个局部事件视界之间存在量子能层,因此解析延拓方法不同于稳态黑洞和v描述的动态黑洞. 展开更多
关键词 黑洞 二维问题 天体物理 量子能层 热辐射
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Energy transfer in organic multilayer quantum well structure and its application to OLEDs 被引量:1
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作者 ZHAO De-wei SONG Shu-fang ZHAO Su-ling XU Zheng 《Optoelectronics Letters》 EI 2007年第2期99-102,共4页
We fabricate a series of samples and OLEDs with organic multilayer quantum well structure, which consist of alternate PBD and Alqy Both PBD and Alq3 are electron-transporting materials, and PBD is used as potential ba... We fabricate a series of samples and OLEDs with organic multilayer quantum well structure, which consist of alternate PBD and Alqy Both PBD and Alq3 are electron-transporting materials, and PBD is used as potential barrier layer, while Alq3 is used as potential well layer and emitting layer. Compared with double-layer structure, the luminescent characteristics of organic samples and diodes with quantum well structure are investigated and the quantum well structure helps the energy transfer between well layer and barrier layer. The quantum well structure makes carriers disperse in the different well layers and then increases the number of excitons to enhance the efficiency of the recombination. 展开更多
关键词 有机多量子阱结构 能量传递 OLED 应用
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Energy Levels of Highly Ionized Ar XIV
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作者 CHENG Zhang LI Ping DENG Xiao-Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4X期723-726,共4页
With the Breit interaction and quantum electrodynamics corrections considered, relativistic configuration interaction calculations have been carried out in the extended optimal level scheme using multi-configuration D... With the Breit interaction and quantum electrodynamics corrections considered, relativistic configuration interaction calculations have been carried out in the extended optimal level scheme using multi-configuration Dirac-Fock wave functions on the 204 energy levels and electric dipole transitions of Ar XIV. The results of electric dipole transitions are in good agreement with experiments. Among the energy levels calculated, the lowest 125 levels are in good agreement with available experimental and other theoretical ones, and the other 79 levels are new ones obtained by the present work. This wide range of atomic energy levels is useful in astrophysics and plasma physics. 展开更多
关键词 Ar ⅩⅣ energy level MCDF RCI
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Conformation and Orientation of Phospholipid Molecule in Pure Phospholipid Monolayer During Compressing
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作者 XUE Weilan WANG Dan ZENG Zuoxiang GAO Xuechao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第2期177-184,共8页
On the basis of energy conservation law and surface pressure isotherm, the conformation energy changes of dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylglycerol (DPPG) in pure phospholipid rnono... On the basis of energy conservation law and surface pressure isotherm, the conformation energy changes of dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylglycerol (DPPG) in pure phospholipid rnonolayer at the air/water interface during compression are derived. The optimized conformations of phospholipids at absolute freedom state are simulated by Gaussian 98 software. Based on following assumptions: (1) the conformation energy change is mainly caused by the rotation of one special bond; (2) the atoms of glycerol near the water surface are active; (3) the rotation is motivated by hydrogen-bond action; (4) the rotation of bond is inertial, one simplified track of conformational change is suggested and the conformations of DPPC and DPPG at different states are determined by the plots of conformation energy change vs. dihedral angle. The thickness of the simulated phospholipid monolayer is consistent with published experimental result. According to molecular areas at different states, the molecular orientations in the compressing process are also developed. 展开更多
关键词 DIPALMITOYLPHOSPHATIDYLCHOLINE dipalmitoylphosphatidylglycerol phospholipid monolayer CONFORMATION ORIENTATION
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First-Principle Studies on Conductive Behaviors of P-Type ZnO Codoped by N and B
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作者 李平 邓胜华 +3 位作者 张学勇 张莉 刘果红 余江应 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期723-727,共5页
Using a first-principle method, the electronic structures and the impurity formation energy of ZnO, ZnO (N), ZnO (N+B), and ZnO (2N+B) have been calculated, based on which the feasibility to obtain p-type ZnO ... Using a first-principle method, the electronic structures and the impurity formation energy of ZnO, ZnO (N), ZnO (N+B), and ZnO (2N+B) have been calculated, based on which the feasibility to obtain p-type ZnO & discussed. According to the results, when ZnO is single doped by N, the acceptor level is deep, and the formation energy is negative, so the ideal p-type ZnO can not be obtained by this way. On the contrary, when 2N+B are codoped into ZnO, the acceptor level becomes much lower, and the formation energy is positive, so it is a better way to obtain p-type ZnO. 展开更多
关键词 FIRST-PRINCIPLES ZnO DOPING
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Large Number,Dark Matter,Dark Energy,and Superstructures in the Universe
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作者 HUANG Wu-Liang HUANG Xiao-Dong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第3期575-576,共2页
Since there may exist dark matter particles ν and δ with mass - 10^-1 e V in the universe, the superstructures with a scale of 10^19 solar masses (large number A - 10^19) appeared during the era near and before th... Since there may exist dark matter particles ν and δ with mass - 10^-1 e V in the universe, the superstructures with a scale of 10^19 solar masses (large number A - 10^19) appeared during the era near and before the hydrogen recombination. Since there are superstructures in the universe, there may be no necessity for the existence of dark energy. For checking the superstructure in the universe by CMB anisotropy, we need to measure CMB angular power spectrum especially around ten degrees across the sky- in more details, While neutrino u is related to electroweak unification, the fourth stable elementary particle 6 may be related to strong-gravity unification, which suggests p + p^- → n + δ^- and that some new baryons appeared in the TeV region. 展开更多
关键词 large number dark matter dark energy stable elementary particle SUPERSTRUCTURE
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Theoretical and experimental study of 2D conformability of stretchable electronics laminated onto skin 被引量:4
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作者 DONG WenTao XIAO Lin +4 位作者 ZHU Chen YE Dong WANG ShuoDao HUANG YongAn YIN ZhouPing 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2017年第9期1415-1422,共8页
Smoothly attaching the stretchable epidermal electronic devices(EEDs) onto the skin surface is highly desired to improve the measurement accuracy of electrophysiological signal.The paper presents an analytical approac... Smoothly attaching the stretchable epidermal electronic devices(EEDs) onto the skin surface is highly desired to improve the measurement accuracy of electrophysiological signal.The paper presents an analytical approach to study interfacial mechanics of the 2D planar EEDs on the checkerboard buckling patterns of human skin.Energy variation method is proposed to determine a criterion whether EEDs laminate conformally onto the skin surface under undeformed and stretched cases.EEDs with low bending stiffness(thin,soft devices/backing layer),smooth and soft skin,and strong adhesion promote conformal contact.Furthermore,the adhesion energy at the EED/skin interface is measured by the homemade peeling experiment platform with different substrate thicknesses and areal coverages.The upper limit of the areal coverage for EED conformal contact with the skin is proposed with given EED/skin properties.Conformability of EEDs are validated by experiments with different substrate thickness,areal coverage and external loadings.It provides a design guideline for EED to conformally contact with the skin surface for more accurate biological signal monitoring. 展开更多
关键词 interfacial mechanics epidermal electronics areal coverage conformability E-skin
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Energetic electron flux distribution model in the inner and middle magnetosphere 被引量:5
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作者 LI Lei FENG YongYong 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第2期441-446,共6页
Based on the magnetospheric kinetic theory, a model is developed to specify the flux of energetic electrons in the inner and middle magnetosphere. Under the assumption of adiabatic motion and isotropic particle distri... Based on the magnetospheric kinetic theory, a model is developed to specify the flux of energetic electrons in the inner and middle magnetosphere. Under the assumption of adiabatic motion and isotropic particle distribution maintained by pitch-angle scattering, the model calculates the electron flux by following bounce-averaged electric field, gradient, and curvature drift in the time dependent electric and magnetic field, meanwhile it counts the electron loss caused by pitch angle scattering. Using the model, the clectron flux distribution during a magnetic storm was calculated and compared with the observation data from the geosynchronous orbit. It is shown that the model can successfully reproduce most of the major electron flux enhancements observed at the geosynchronous orbit and generally tracks the satellite data well. The rms errors of the modeled logarithm of flux are between 0.5-1.0. 展开更多
关键词 MAGNETOSPHERE energetic electron electron flux distribution
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An analysis of the correlation between the fluxes of high-energy electrons and low-middle-energy electrons in the magnetosphere 被引量:2
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作者 LI ChenFang ZOU Hong +4 位作者 ZONG QiuGang JIA XiangHong CHEN HongFei SHI WeiHong YU XiangQian 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第7期1130-1136,共7页
The variation of the flux of energetic electrons in the magnetosphere has been proven to be strongly related to the solar wind speed. Observations of GEO orbit show that the flux of low-energy electrons is not only mo... The variation of the flux of energetic electrons in the magnetosphere has been proven to be strongly related to the solar wind speed. Observations of GEO orbit show that the flux of low-energy electrons is not only modulated by the solar wind speed, but, if a time delay is added, is also positively correlated to the flux of high-energy electrons. This feature provides a possible method to forecast the flux of high-energy electrons in GEO orbit. In this study, the correlations of the fluxes between the high-energy electrons and low-middle-energy electrons obtained at different L values and in different orbits are investigated to develop the application of this feature. Based on the analysis of long–term data observed by NOAA POES and GOES, the correlations between the fluxes of high-energy electrons and low–middle–energy electrons are good enough at different L values and in different orbits in quiet time, but this correlation is strongly affected by CME–driven geomagnetic storms. 展开更多
关键词 magnetosphere high-energy electrons low-middle energy electrons forecast model
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Novel layered K0.7Mn0.7Ni0.3O2 cathode material with enlarged diffusion channels for high energy density sodium-ion batteries 被引量:1
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作者 Jinghui Chen Zhitong Xiao +5 位作者 Jiashen Meng Jinzhi Sheng Yanan Xu Junjun Wang Chunhua Han Liqiang Mai 《Science China Materials》 SCIE EI CSCD 2020年第7期1163-1170,共8页
As promising,low-cost alternatives of lithiumion batteries for large-scale electric energy storage,sodiumion batteries(SIBs)have been studied by many researchers.However,the relatively large size of Na+leads to sluggi... As promising,low-cost alternatives of lithiumion batteries for large-scale electric energy storage,sodiumion batteries(SIBs)have been studied by many researchers.However,the relatively large size of Na+leads to sluggish diffusion kinetics and poor cycling stability in most cathode materials,restricting their further applications.In this work,we demonstrated a novel K+-intercalated Mn/Ni-based layered oxide material(K0.7Mn0.7Ni0.3O2,denoted as KMNO)with stabilized and enlarged diffusion channels for high energy density SIBs.A spontaneous ion exchange behavior in forming K0.1Na0.7Mn0.7Ni0.3O2between the KMNO electrode and the sodium ion electrolyte was clearly revealed by in situ X-ray diffraction and ex situ inductively coupled plasma analysis.The interlayer space varied from 6.90 to 5.76?,larger than that of Na0.7Mn0.7Ni0.3O2(5.63?).The enlarged ionic diffusion channels can effectively increase the ionic diffusion coefficient and simultaneously provide more K+storage sites in the product framework.As a proof-of-concept application,the SIBs with the as-prepared KMNO as a cathode display a high reversible discharge capacity(161.8 mA h g-1at0.1 A g-1),high energy density(459 W h kg-1)and superior rate capability of 71.1 mA h g-1at 5 A g-1.Our work demonstrates that the K+pre-intercalation strategy endows the layered metal oxides with excellent sodium storage performance,which provides new directions for the design of cathode materials for various batteries. 展开更多
关键词 K0.7Mn0.7Ni0.3O2 K^+pre-intercalation enlarged layered structure high energy density sodium-ion batteries
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An electron momentum spectroscopic study of naphthalene in gas phase
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作者 SHI LeLei LIU Kun +1 位作者 NING ChuanGang DENG JingKang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第11期1981-1989,共9页
We report the experimental and theoretical investigation of the complete valence shell binding energy spectra and momentum profiles of naphthalene (C 10 H 8),using our high resolution electron momentum spectrometer,at... We report the experimental and theoretical investigation of the complete valence shell binding energy spectra and momentum profiles of naphthalene (C 10 H 8),using our high resolution electron momentum spectrometer,at impact energies of 1500 eV and 600 eV.The observed momentum profiles were compared with the Hartree-Fock (HF) and density functional theory (DFT) calculations,and the binding energy spectrum was compared with the Outer valence Green's function (OVGF) calculations.The impact energy dependent discrepancy between observed momentum distributions and calculations under the plane wave impulse approximation was ascribed to the distorted wave effects. 展开更多
关键词 NAPHTHALENE EMS distorted wave effects
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First-principles calculation of the structure and the energy of ZrO_2/Al_2O_3 nanomultilayer 被引量:4
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作者 GAO Xue ZHANG Yue SHANG JiaXiang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第11期1990-1999,共10页
The electronic structure, atomic geometry and energetic properties of ceramic nanomultilayer have been systematically studied with first principles density functional theory calculations based on the generalized gradi... The electronic structure, atomic geometry and energetic properties of ceramic nanomultilayer have been systematically studied with first principles density functional theory calculations based on the generalized gradient approximations. It is found that the interface structure and adhesion, which determine the mechanical and thermal properties, are sensitive to the surface mor- phology. We also provide an analysis of adhesion of ZrO2/A1203 interface as a function of thickness of each layer. With the in- crease of ZrO2 thickness, both covalence and ionicity of the interfacial bonds are enhanced, which results in more strongly coupled interfaces while the ionic interaction decreases for thicker Al2O3 layers, which results in weakly coupled interfaces. A first-principles calculation method has been proposed to design nanomultilayer materials to achieve the demanded adhesion. 展开更多
关键词 nanomultilayer first principles INTERFACE
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