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Changing Rules of Bonding Electron Pair Correlation Energies of CH_3X (X=F,OH,NH_2) Systems
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作者 ZHUOShu-Ping SIWei-Jiang JUGuan-Zhi 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第5期525-531,共7页
The pair correlation energy of bonding electrons is used and analyzed in the cal- culation of CH and CY (Y = F, O, N) bonding electron pairs in CH3X (X = F, OH, NH2) isoelec- tronic systems based on intra- and interpa... The pair correlation energy of bonding electrons is used and analyzed in the cal- culation of CH and CY (Y = F, O, N) bonding electron pairs in CH3X (X = F, OH, NH2) isoelec- tronic systems based on intra- and interpair correlation energy results at both MP2-OPT2/6- 311++G(d) and MP2-OPT2/cc-pVtz levels with MELD program. Comparison of two set results shows that cc-pVtz and 6-311++G(d) give more correlation energy of valence electrons and innermost core electron pairs, respectively in these systems, resulting that the total correlation energy with cc-pVtz basis of each system is larger than that with 6-311++G(d). Investigations of pair correlation energy show that with the decrease of electronegativity of X atom and the increase of H atoms in these CH3X (X = F, OH, NH2) systems, the pair correlation energy of 1sC2 of the C atoms is transferable, and the correlation energy of CH bonding electron pair with little changes is of approximate transferability, while those of CY (CF, CO, CN) bonding electron pair decrease in a large extent from CH3F through CH3OH to CH3NH2 molecules. It is suggested that the study of pair correlation energy of bonding electrons will further deepen the understanding of electron corre- lation effect from traditional chemical bonding concept. 展开更多
关键词 pair correlation energy bonding electron pair CH3X systems
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Transport of Electron Pairs in a Superconducting Junction Device: Underdamped Case
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作者 LI Jing-Hui HAN Yin-Xia 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6期1031-1034,共4页
在在欠阻尼的案例中的一台超导的连接设备的电子对的运输被调查。连接的电容能减缓电子对的运动并且减少网电压,这被显示出。它也被看那,为欠阻尼的案例并且过去抑制大小写,在这台超导的连接设备的电子对的运动有一些类似的特征。由... 在在欠阻尼的案例中的一台超导的连接设备的电子对的运输被调查。连接的电容能减缓电子对的运动并且减少网电压,这被显示出。它也被看那,为欠阻尼的案例并且过去抑制大小写,在这台超导的连接设备的电子对的运动有一些类似的特征。由控制在添加剂和趋于增加的噪音之间的关联,流动能被颠倒。另外,如果添加剂噪音力量(或温度 T ) 足够大,颠倒能也被导致。 展开更多
关键词 超导结 电子对 噪声 电容 不完全衰减
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Appearance of Spatial-Temporal Noise in Super-conducting Junction and Its Effect on Transport of Electron Pairs
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作者 LI Jing-Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第4期669-671,共3页
在超导的连接的电子对的运输 withspatial 时间的噪音被调查。我们证明空间时间的噪音能生产电子对的电流,它源自与阶段差别的空间时间的噪音的关联导致的系统碎的对称。为电子对有积极电流,这被发现,展出有增加噪音的一些参数的值... 在超导的连接的电子对的运输 withspatial 时间的噪音被调查。我们证明空间时间的噪音能生产电子对的电流,它源自与阶段差别的空间时间的噪音的关联导致的系统碎的对称。为电子对有积极电流,这被发现,展出有增加噪音的一些参数的值的一座山峰。结果为超导的连接的进一步的调查提供一个理论基础。 展开更多
关键词 超导结 时空噪声 电子对传输 约瑟夫森结
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Formation of Slow Electron Pairs in an External Coulomb Field
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作者 Hubert Klar 《Journal of Modern Physics》 2017年第7期1029-1042,共14页
The wave equation for two electrons in an external Coulomb field (helium-like atoms) has been shown to be a problem in a three-dimensional half-space. The wave-equation becomes quasi-separable in inertial coordinates.... The wave equation for two electrons in an external Coulomb field (helium-like atoms) has been shown to be a problem in a three-dimensional half-space. The wave-equation becomes quasi-separable in inertial coordinates. This allows to work out the electron motion in the frame of principal inertia axes. We find that non-adiabatic coupling terms constitute a fictitious force and lead to a deformation of the static potential surface. Incoming and outgoing modes of electron pairs are studied in detail, and applied to the threshold ionization of hydrogen-like atoms by electrons. Our analysis confirms the classical work by Wannier. However, we go beyond Wannier and present bending and stretch vibrations of electron pairs. The bending vibration has no influence onto the total ionization cross-section. The pair formation below threshold destroys the existence of high double Rydberg resonances. Finally, we describe the propagation of an electron pair through a linear chain of Rydberg atoms. 展开更多
关键词 DOMINANT Correlation Wannier THRESHOLD LAW electron pairS
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Enhancement of electron–positron pairs in combined potential wells with linear chirp frequency
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作者 王莉 李烈娟 +4 位作者 麦丽开·麦提斯迪克 安荣 李静静 谢柏松 张丰收 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期153-160,共8页
Effect of linear chirp frequency on the process of electron–positron pairs production from vacuum is investigated by the computational quantum field theory.With appropriate chirp parameters,the number of electrons cr... Effect of linear chirp frequency on the process of electron–positron pairs production from vacuum is investigated by the computational quantum field theory.With appropriate chirp parameters,the number of electrons created under combined potential wells can be increased by two or three times.In the low frequency region,frequency modulation excites interference effect and multiphoton processes,which promotes the generation of electron–positron pairs.In the high frequency region,high frequency suppression inhibits the generation of electron–positron pairs.In addition,for a single potential well,the number of created electron–positron pairs can be enhanced by several orders of magnitude in the low frequency region. 展开更多
关键词 electron–positron pairs linear chirp frequency the computational quantum field theory
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Electronic properties of graphene nanoribbon doped by boron/nitrogen pair:a first-principles study 被引量:7
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作者 肖金 杨志雄 +3 位作者 谢伟涛 肖立新 徐慧 欧阳方平 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期450-456,共7页
By using the first-principles calculations, the electronic properties of graphene nanoribbon (GNR) doped by boron/nitrogen (B/N) bonded pair are investigated. It is found that B/N bonded pair tends to be doped at ... By using the first-principles calculations, the electronic properties of graphene nanoribbon (GNR) doped by boron/nitrogen (B/N) bonded pair are investigated. It is found that B/N bonded pair tends to be doped at the edges of GNR and B/N pair doping in GNR is easier to carry out than single B doping and unbonded B/N co-doping in GNR. The electronic structure of GNR doped by B/N pair is very sensitive to doping site besides the ribbon width and chirality. Moreover, B/N pair doping can selectively adjust the energy gap of armchair GNR and can induce the semimetal-semiconductor transmission for zigzag GNR. This fact may lead to a possible method for energy band engineering of GNRs and benefit the design of graphene electronic device. 展开更多
关键词 graphene nanoribbons boron/nitrogen pairs doping electronic properties firstprinciples
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The Characteristics of the Cooper Pair Electrons in High Tc Copper Oxide Superconductors 被引量:1
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作者 Yu Chen Li Yu Jinbin Yao 《材料科学与工程(中英文A版)》 2014年第5期160-163,共4页
关键词 铜氧化物超导体 超导特性 电子对 高温超导 电子特性 库珀对
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INTRA-ION PAIR ELECTRON TRANSFER OF PHOTOEXCITED METHYLENE BLUE BORATE
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作者 Xiu Zhi WANG Han Qing CHEN Er Jian WANG (Institute of Photographic Chemistry, Academia Sinica, Beijing 100101National Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou,730000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1995年第7期597-600,共4页
The photochemical reaction of methylene blue (n-butyltriphenyl) borate, MBRBPh3 was examined. The ultrafast quenching rate and large negative value of Delta G indicated that the intra-ion pair ET plays an important ro... The photochemical reaction of methylene blue (n-butyltriphenyl) borate, MBRBPh3 was examined. The ultrafast quenching rate and large negative value of Delta G indicated that the intra-ion pair ET plays an important role in photoreaction of MBRBPh3. The sequent boron- carbon bond cleavage of butyltriphenylboranyl radical intermediate was found by GC-MS and photo-CIDNP studies. 展开更多
关键词 ION INTRA-ION pair electron TRANSFER OF PHOTOEXCITED METHYLENE BLUE BORATE
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Electronic Structures and Spectra of the Bases and Base Pairs of Nucleic Acids 被引量:1
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作者 WANG Zhi-zhong and BAI Ya-wen (Institute of Theoretical Chemistry, Jilin University, Changchun, 130023) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1992年第2期89-95,共7页
The present paper covers electronic structures and spectra of the bases and the base pairs of nucleic acids calculated by using the INDO/S method. For free bases we give the energy levels of ground states and transiti... The present paper covers electronic structures and spectra of the bases and the base pairs of nucleic acids calculated by using the INDO/S method. For free bases we give the energy levels of ground states and transition energies of low-lying excited states and discuss the band characters. The results indicate that the calculated spectra are in good agreement with experimental values. On the other hand, our calculations for A-T and G-C pairs are very beneficial to understanding hydrogen bond properties of these pairs. 展开更多
关键词 Bases and base pairs of nucleic acid electronic structures and spectra INDO/S
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An Electron Model Consistent with Electron-Positron Pair Production from High Energy Photons 被引量:1
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作者 Donald Bowen Robert V. Mulkern 《Journal of Modern Physics》 2015年第9期1334-1342,共9页
This is a rotating charge loop model of an electron which explains the electron’s de Broglie base frequency to an accuracy of over 6 decimal places. The model also predicts the magnetic moment of the electron to over... This is a rotating charge loop model of an electron which explains the electron’s de Broglie base frequency to an accuracy of over 6 decimal places. The model also predicts the magnetic moment of the electron to over 6 decimal places and helps explain the transition from a purely electromagnetic photon to a fermion state of matter. The model also explains how charge and spin are conserved in the transition. Finally, this concept might be extended to explain the muon and tau higher energy states of the electron as well. 展开更多
关键词 electron POSITRON Loop MUON Tau pair Production Photon FERMION Magnetic Moment De BROGLIE
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The Origination of the Cooper Pair Electrons with Doping in High Tc Copper Oxides
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作者 Jinbin Yao Yu Chen Li Yu 《材料科学与工程(中英文A版)》 2015年第1期47-49,共3页
关键词 铜氧化物超导体 高温超导 电子对 起源 兴奋剂 超导机制 掺杂特性 并发症
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The Nature of the Cooper Pair Electrons on High Tc Copper Oxides
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作者 Li Yu Yu Chen 《材料科学与工程(中英文B版)》 2014年第12期388-391,共4页
关键词 铜氧化物 电子对 高温超导 性质 超导性能 电负性均衡 发生变化 特征元素
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The Cooper Pair Electrons Origination in Copper Oxide Superconductors
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作者 Jinbin Yao Yu Chen 《材料科学与工程(中英文A版)》 2015年第3期109-112,共4页
关键词 铜氧化物超导体 电子对 起源 化学键理论 对称性 氧化铜 高温超导 性质变化
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Electron-Proton Pairing at High Temperatures, Solar Flares, and the FIP Effect
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作者 L. K. Pande 《Journal of Modern Physics》 2016年第1期25-35,共11页
We analyze the line data from solar flares to present evidence for the emission spectrum of the recently discussed electron-proton pairs at high temperatures. We also point out that since the pairing phenomenon provid... We analyze the line data from solar flares to present evidence for the emission spectrum of the recently discussed electron-proton pairs at high temperatures. We also point out that since the pairing phenomenon provides an additional source for these lines—the conventional source being the highly ionized high-Z atoms already existing in the solar atmosphere, we have a plausible explanation of the FIP effect. 展开更多
关键词 electron-Proton pairing at High Temperatures Emission Spectra from Solar Flares FIP Effect
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双振荡场产生正负电子对的理论研究
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作者 李传可 林南省 +2 位作者 周鲜鲜 江淼 李英骏 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第4期151-160,共10页
在强电磁场下真空产生正负电子对的研究中,多场的组合扮演重要的角色.本文运用计算量子场论方法在全时空数值求解狄拉克方程,研究了两个空间分离的局域化振荡电场击穿真空产生正负电子对的过程.结果表明通过选取合适的场参数,两场的相... 在强电磁场下真空产生正负电子对的研究中,多场的组合扮演重要的角色.本文运用计算量子场论方法在全时空数值求解狄拉克方程,研究了两个空间分离的局域化振荡电场击穿真空产生正负电子对的过程.结果表明通过选取合适的场参数,两场的相互作用可以显著增强正负电子对的产生.两场的相互作用使产生正负电子对的动量分布曲线出现了周期性的振荡,并导致了非对称的多光子跃迁过程.通过含时微扰理论分析得出,正负电子对的动量分布的周期性振荡可由电场宽度、电场频率和两场间距共同决定.两场间距能够改变正负电子对动量分布的变化周期,随着两场间距的增大,产生正负电子对的动量(能量)的单一性得到优化;电场宽度不仅影响正负电子对动量分布的峰谷高度差,还会改变其在动量空间峰值的展宽;根据能量守恒定律,电场频率的增大使得产生粒子对的动量随之变大.因此,通过选择合适电场参数可以抑制或加强特定动量分布的正负电子对,这为今后的实验设计提供了重要的理论指导. 展开更多
关键词 正负电子对产生 计算量子场论 强场物理
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单线态裂分中间态的理论研究进展
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作者 童磊 张春峰 《物理学进展》 北大核心 2024年第3期112-122,共11页
单线态裂分是指有机材料在光激发后,从一个单重态激子转变为两个三重态激子的光物理过程。该过程有望提高光电转换效率,因而受到了广泛的关注。研究发现单线态裂分中存在一个关键的中间态,而如何构建中间态的波函数则是重要的挑战。本... 单线态裂分是指有机材料在光激发后,从一个单重态激子转变为两个三重态激子的光物理过程。该过程有望提高光电转换效率,因而受到了广泛的关注。研究发现单线态裂分中存在一个关键的中间态,而如何构建中间态的波函数则是重要的挑战。本文着重介绍了双激发态波函数构建的两类理论模型,而后讨论了振动、轨道和自旋相互作用对中间态形成和解离的影响。最后总结了进一步的理论研究将面临的挑战。 展开更多
关键词 单线态裂分 双激发态 电子态耦合 交换相关能
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Coulomb Interaction between Electrons and a New Concept of Atom
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作者 Marina V. Krasinkova 《Journal of Modern Physics》 2022年第4期495-508,共14页
It is shown that the approximation of a strong Coulomb interaction between electrons results in a new model of the atom with a spatial quantization of electrons accompanied by their quantization in energy. This model ... It is shown that the approximation of a strong Coulomb interaction between electrons results in a new model of the atom with a spatial quantization of electrons accompanied by their quantization in energy. This model implies that electrons rotate in circular orbits centered outside the atomic nucleus and only orbit axes pass through it. The Coulomb interaction between electrons leads to a spherically symmetric distribution of their orbits on the surfaces of equipotential spheres of a spherically symmetric electrostatic field of the nucleus. The distribution is similar to “inscribing” electron orbits into faces of regular nucleus-centered polyhedra so each polyhedron corresponds to a certain electron state (s, p, d, f), and a certain set of polyhedra corresponds to a certain period of the Mendeleev Table. It is shown that a spherically symmetric distribution of electron orbits gives rise to the formation of electron pairs in which electron orbits with a common axis are located symmetrically with respect to the nucleus and the orbital magnetic moments of the electrons are oppositely directed. The physical meaning of the electron spin concept becomes clear. The spin turns out to be related to the orbital magnetic moment of an electron and reflects the fact that two electrons of a pair rotate in opposite directions relative to their common axis. So the spin is one of characteristics of the electron state in the atom associated with electron rotation in the orbit centered outside the nucleus. The atomic model gives an insight into the periodicity of changes in the atomic properties with increasing nuclear charge and the reasons for an electron double energy quantization associated with different states and periods. The model shows that the atomic structure and properties can be explained by using concepts of classical mechanics and classical electrodynamics which regard the electron as a particle. 展开更多
关键词 Correlated electron State electron Shell Structure electron Energy Quantization electron pairing electron Spin Magnetic Dipole-Dipole Interaction Closed System
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Model of Preformed Hole-Pairs in c-Axis Transport in Cuprate Superconductors 被引量:1
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作者 Rana Janardan Singh 《World Journal of Condensed Matter Physics》 2012年第4期228-236,共9页
Model of hole-pairs in electrical transport along ab plane in cuprate superconductors has already been proposed. It has been found to be in the shape of 3dx2–y2 orbital of an electron in an atom. This time, model of ... Model of hole-pairs in electrical transport along ab plane in cuprate superconductors has already been proposed. It has been found to be in the shape of 3dx2–y2 orbital of an electron in an atom. This time, model of hole-pairs in transport along c-axis in cuprate superconductors is proposed. In ab-plane, hole-pairs are formed along CuO2 plane;one hole-pair covering 9 - 10 two dimensional CuO2 unit cells in 3dx2–y2 configuration. In the investigation of c-axis hole-pairs, cuprate superconductors have been sub-divided into three categories depending on the number of CuO2 planes/formula unit. There is a little different treatment for finding out the order parameter in each category. Coherence lengths along ab-planes are of the order of a few tens of Angstroms, whereas along c-axis, they are less than even their a-, b-lattice constants. In cuprates with 2 or 3 CuO2 planes, the order parameter is of 3dz2–x2 type in zx-plane with lobes along both the axes much constrained. For cuprates with a single CuO2 layer, the order parameter is of 3dx2–y2 type, but its dimensions are less than a-, b-lattice constants. 展开更多
关键词 CUPRATE SUPERCONDUCTORS PREFORMED Hole-pairs electron PARAMAGNETIC Resonance 41 meV Peak in Neutron Diffraction
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Dynamical effects of switching a super-critical well potential on pair creation from a vacuum
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作者 王强 夏勤智 +1 位作者 刘杰 傅立斌 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期103-108,共6页
The dynamical effects on electron-positron pair creation from a vacuum caused by the switching processes of a super- critical well potential are investigated in detail. The results show that only when the switching on... The dynamical effects on electron-positron pair creation from a vacuum caused by the switching processes of a super- critical well potential are investigated in detail. The results show that only when the switching on and switching off time both increase will the final pair yield converge to the integer of embedded bound states nearly exponentially. But a single adiabatic switching on or switching off cannot lead to an integer pair yield. If the potential is turned on abruptly, associated with the discrete and embedded bound states, there is multi-frequency oscillation around the pair number's saturation. The slowly switching on can suppress the amplitude of this oscillation and reduce the final pair yield. The switching off can also reduce the final pair number in the same order of magnitude. The evolution of a single-pair number shows a robust long range correlation between particle and antiparticle. For an adiabatic switching case, the single-pair dominates the early pair creation, their upper limit value is equal to the integer, and these single-pairs will totally disentangle during the switching off. 展开更多
关键词 electron-positron pair creation dynamical effect
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Numerical studies on pair production in ultra-intense laser interaction with a thin solid-foil
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作者 田云先 金晓林 +3 位作者 谷晓梁 颜卫忠 李建清 李斌 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第8期11-15,共5页
A theoretical and numerical model of photon and electron–positron pair production in strong-field quantum electrodynamics(QED) is described. Two processes are contained in our QED theoretical model, one is photon e... A theoretical and numerical model of photon and electron–positron pair production in strong-field quantum electrodynamics(QED) is described. Two processes are contained in our QED theoretical model, one is photon emission in the interaction of ultra-intense laser with relativistic electron(or positron), and the other is pair production by a gamma-ray photon interacting with the laser field.This model has been included in a PIC/MCC simulation code named BUMBLEBEE 1 D, which is used to simulate the laser plasma interaction. Using this code, the evolutions of electron–positron pair and gamma-ray photon production in ultra-intense laser interaction with aluminum foil target are simulated and analyzed. The simulation results revealed that more positrons are moved in the opposite direction to the incident direction of the laser under the charge separation field. 展开更多
关键词 QED ultra-intense laser gamma ray photon electron-positron pair
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