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Formation Mechanism and Binding Energy for Equilateral Triangle Structure of He3^+ Cluster 被引量:6
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作者 GOU Qing-Quan ZHANG Jian-Ping LI Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第5期597-600,共4页
The formation mechanism for the equilateral triangle structure of the He-3(+) cluster is proposed. The curve of the total energy versus the internuclear distance R for this structure has been calculated by the method ... The formation mechanism for the equilateral triangle structure of the He-3(+) cluster is proposed. The curve of the total energy versus the internuclear distance R for this structure has been calculated by the method of a modified arrangement channel quantum mechanics. The result shows that the curve has a minimal -7.81373 a. u at R = 1.55 a(0). The binding energy of He-3(+) with respect to He+He++He was calculated to be 0.1064 a.u. (about 2.89 eV). This means that the He-3(+) cluster may be formed in the equilateral triangle structure stably by the interaction of He+ with two helium atoms. 展开更多
关键词 He-3(+) cluster binding energy equilateral triangle structure
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Formation Mechanism and Binding Energy for Body-Centered Cubic Structure of He^+9 Cluster 被引量:6
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作者 ZHANGJian-Ping GOUQing-Quan LIPing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第1期101-105,共5页
The formation mechanism for the body-centered cubic structure of cluster is proposed and its total energy curve is calculated by the method of a Modified Arrangement Channel Quantum Mechanics. The energy is the funct... The formation mechanism for the body-centered cubic structure of cluster is proposed and its total energy curve is calculated by the method of a Modified Arrangement Channel Quantum Mechanics. The energy is the function of separation R between the nuclei at the center and an apex of the body-centered cubic structure. The result of the calculation shows that the curve has a minimal energy . The binding energy of with respect to was calculated to be 0.8857 a.u. This means that the cluster ofmay be formed in the body-centered cubic structure of . 展开更多
关键词 He-+(9) cluster binding energy body-centered cubic structure
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Formation Mechanism and Binding Energy for Equilateral Triangle Structure of Li3 Cluster 被引量:1
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作者 YANG Jian-Hui LI Ping GOU Qing-Quan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3X期525-528,共4页
The formation mechanism for the equilateral triangle structure of Lia cluster is proposed. The curve of the total energy versus the interatomic distance for this structure has been calculated by using the method of Go... The formation mechanism for the equilateral triangle structure of Lia cluster is proposed. The curve of the total energy versus the interatomic distance for this structure has been calculated by using the method of Gou's Modified Arrangement Channel Quantum Mechanics. The result shows that the curve has a minimal energy of-22.338 60 a.u at R = 5.82 ao. The total energy of Lia when R approaches co has the value of-22.284 09 a.u. This is also the total energy of three lithium atoms dissociated from Lia. The difference value of 0.0545 08 a.u. for the above two energy values is the dissociation energy of Li3 cluster, which is also its binding energy. Therefore the binding energy per lithium atom for Lia is 0.018 169 a.u. = 0.494 eV, which is greater than the binding energy of 0.453 eV per atom for Li2 calculated in a previous work. This means that the Li3 cluster may be formed in the equilateral triangle structure of side length R = 5.82ao stably with a stronger binding from the symmetrical interaction among the three lithium atoms. 展开更多
关键词 Li3 cluster binding energy equilateral triangle structure
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Formation Mechanism and Binding Energy for Equilateral Triangle Structure of He3+ Cluster
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作者 GOU Qing-Quan ZHANG Jian-Ping LI Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第11期597-600,共4页
The formation mechanism for the equilateral triangle structure of the He3+ cluster is proposed. The curveof the total energy versus the internuclear distance R for this structure has been calculated by the method of a... The formation mechanism for the equilateral triangle structure of the He3+ cluster is proposed. The curveof the total energy versus the internuclear distance R for this structure has been calculated by the method of a modifiedarrangement channel quantum mechanics. The result shows that the curve has a minimal -7.81373 a.u at 1 = 1.55 a0.The binding energy of He3+ with respect to He+He+ +He was calculated to be 0.1064 a.u. (about 2.89 eV). This meansthat the He3+ cluster may be formed in the equilateral triangle structure stably by the interaction of He+ with two heliumatoms. 展开更多
关键词 He3+ cluster binding energy equilateral TRIANGLE structure
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Binding energy and fine structure of the He^- ion
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作者 卓琳 《原子与分子物理学报》 CAS CSCD 北大核心 2007年第B08期18-20,共3页
The variational method using a multiconfiguration wavefunction is carried out on the core-excited state 1s2s2p 4P0 for helium negative ion,including mass polarization and relativistic corrections.Binding energy and fi... The variational method using a multiconfiguration wavefunction is carried out on the core-excited state 1s2s2p 4P0 for helium negative ion,including mass polarization and relativistic corrections.Binding energy and fine structure are reported.The results are compared with other theoretical and experimental date in the literature. 展开更多
关键词 氦负离子 电子 原子光谱 能量
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RETRACTED: Nuclear Structure Study of Odd-Odd Yttrium Nuclei within Interacting-Boson Fermi-Fermion Model (IBFFM)
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作者 Afrah J. Mohaisen Saad N. Abood 《Journal of Applied Mathematics and Physics》 2024年第6期2020-2031,共12页
Short Retraction NoticeThe paper does not meet the standards of "Journal of Applied Mathematics and Physics". This article has been retracted to straighten the academic record. In making this decision the Ed... Short Retraction NoticeThe paper does not meet the standards of "Journal of Applied Mathematics and Physics". This article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's Retraction Guidelines. The aim is to promote the circulation of scientific research by offering an ideal research publication platform with due consideration of internationally accepted standards on publication ethics. The Editorial Board would like to extend its sincere apologies for any inconvenience this retraction may have caused.Editor guiding this retraction: Prof. Wen-Xiu Ma (EiC of JAMP)The full retraction notice in PDF is preceding the original paper, which is marked "RETRACTED". 展开更多
关键词 Nuclear structure Yttrium Nuclei Interacting Boson-Fermion Model energy spectra Electromagnetic Transition Rates
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The Potential Energy of Nucleon and Nuclear Structure
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作者 Bin Liang 《Journal of Modern Physics》 2016年第14期1866-1873,共8页
This article proposes the potential energy function of nucleon in nucleus, derives the expression equation of nuclear force, shows that nucleus has the shell structure by the solving the Schr?dinger equation of nucleo... This article proposes the potential energy function of nucleon in nucleus, derives the expression equation of nuclear force, shows that nucleus has the shell structure by the solving the Schr?dinger equation of nucleon, obtains the magic numbers, and interprets the past experimental results in theory;for example the radius of nucleus is proportional to the cubic root of nucleon number, the nuclear force is repulsive in the depths of nucleus and attractive in the surface layer, and the variation of average binding energy of nucleons with the nucleon number. 展开更多
关键词 Potential energy of Nucleon Nuclear Force Shell structure Average binding energy
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Pairing Effect on the Binding Energy Curve of N = Z Atomic Nuclei
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作者 Bernard Schaeffer 《World Journal of Nuclear Science and Technology》 2013年第3期79-82,共4页
The saw-tooth phenomenon on the binding energy curve of N = Z nuclei is due to the low binding energy between the α-particles. It was suspected by Gamow to be of van der Waals type, found here to be deuteron bonds. T... The saw-tooth phenomenon on the binding energy curve of N = Z nuclei is due to the low binding energy between the α-particles. It was suspected by Gamow to be of van der Waals type, found here to be deuteron bonds. The binding energy per nucleon, in absolute value, of an α-particle is larger than any other combination of 4 nucleons. Therefore, the binding energy per nucleon is low for odd-odd N = Z nuclei and maximum for even-even N = Z nuclei. The assumption of N = Z nuclei to be an assembly of α-particles and deuteron bonds predicts the binding energy of the 32 first N = Z nuclei with a rms deviation of 0.25 MeV. 展开更多
关键词 Nuclear structure binding ENERGIES MASSES Cluster Models
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Ab Initio Studies on the Structure and Binding Interaction of M^+CO_2(M=Sc,Ti…Zn) 被引量:1
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作者 FAN Hong-Jun ZHONG Shi-Jun LIU Chun-Wan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1998年第2期80-85,共6页
The geometry and binding interaction of M+CO2 (M represents the firstrow transition metals) were studied using ab initio methods. In some cases the frequency calculations and basis set superposition error corrections ... The geometry and binding interaction of M+CO2 (M represents the firstrow transition metals) were studied using ab initio methods. In some cases the frequency calculations and basis set superposition error corrections were included. For all the complexes under the study, the linear structures were found to be the equilibrium structure. The distances of M+—O in R(M+—O) in which M has 4s electrons are obvious longer than those in which M has no 4s electrons, and from Sc to Zn the change trend is decreased, accompanied with some oscillation. The binding energy has an opposite change trend to that of the R(M+—O). Linear M+CO2 has the same spin as M+, while Tshape structures may have different spins. The static electronic interaction was found to be about 80% of the total binding energy. 展开更多
关键词 Chargeinduced dipole interaction binding energy Equilibrium structure Ab initio
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Effect of local structure on electron paramagnetic resonance spectra for trigonal [Cr(H_2O)_6]^(3+) coordination complex in the sulfate alums series:a ligand field theory study
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作者 李艳芳 邝小渝 +2 位作者 高明亮 赵亚儒 王怀谦 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期2967-2974,共8页
A simple theoretical method is introduced for studying the interrelation between electronic and molecular structures.By diagonalizing the 120 × 120 complete energy matrices,the relationships between zero-field sp... A simple theoretical method is introduced for studying the interrelation between electronic and molecular structures.By diagonalizing the 120 × 120 complete energy matrices,the relationships between zero-field splitting (ZFS) parameter D and local distortion parameter △θ for Cr^3+ ions doped,separately,in α- and β- alums are investigated.Our results indicate that there exists an approximately linear relationship between D and △θ in a temperature range 4.2-297 K and the signs of D and △θ are opposite to each other.Moreover,in order to understand the contribution of spin-orbit coupling coefficient ζ to ZFS parameter D,the relation between D and ζ is also discussed. 展开更多
关键词 complete energy matrices electron paramagnetic resonance (EPR) spectra local structure
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Theoretical and Experimental Study of the Mechanism of Reaction Formation of Cyanine Dyes
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作者 Boshkayeva Assyl Omarova Roza +1 位作者 Pichkhadze Guram Shalpykova Nasiba 《International Journal of Organic Chemistry》 2014年第5期279-285,共7页
To study the theoretical bases of the mechanism of reaction formation of cyanine dyes, special importance is gained by methods of quantum chemistry. The use of these methods is provided with the known molecular and dy... To study the theoretical bases of the mechanism of reaction formation of cyanine dyes, special importance is gained by methods of quantum chemistry. The use of these methods is provided with the known molecular and dynamic HyperChem program. The purpose of studying was quantum and chemical studying of features of a geometrical and electronic structure of model molecules of penicillin acid, of derivative of glutaconic dialdehyde (DGD), and the cyanine dyes, and also an assessment of power of process of their formation. For studying was carried out the experimental mark of chemism of course of reaction with theoretical justification of the mechanism of reaction formation of cyanine dyes. The results show that all studied model molecules are thermodynamic steady systems to what values of enthalpies of their formation, rather high on an absolute value, testify negative on a sign. Reaction goes by the mechanism of nucleophilic addition. 展开更多
关键词 Cyanine dye Β-LACTAM Quantum-Chemical Method PENICILLIN Acid DERIVATIVE of Glutaconic DIALDEHYDE Electronic Density The binding energy HyperChem
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Liquid Water Structure from Anomalous Density under Ambient Condition
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作者 孙樯 郑海飞 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第11期3022-3024,共3页
From discussion of the structure of liquid water, we deduce that water under ambient condition is mainly composed of ice Ih-like molecular dusters and clathrate-like molecular clusters. The water molecular dusters rem... From discussion of the structure of liquid water, we deduce that water under ambient condition is mainly composed of ice Ih-like molecular dusters and clathrate-like molecular clusters. The water molecular dusters remain in a state of chemical equilibrium (reversible clustering reactions). This structural model can be demonstrated by quantitative study on anomalous density with increasing temperature at ambient pressure. 展开更多
关键词 LOW-energy structureS AB-INITIO HEXAMER CLUSTERS TEMPERATURE SPECTROSCOPY PRESSURE spectra CAGE
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Electronic structures and physical properties of pure Cr,Mo and W 被引量:2
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作者 谢佑卿 邓永平 刘心笔 《中国有色金属学会会刊:英文版》 CSCD 2003年第5期1102-1107,共6页
Using the one atom theory, the electronic structures of pure Cr, Mo and W with bcc structure were determined respectively as: [Ar] (3d c) 3.32 (3d n) 2.26 (4s c) 0.25 (4s f) 0.17 , [Kr] (4d c) 4.23 (4d n) 1.48 (5s c) ... Using the one atom theory, the electronic structures of pure Cr, Mo and W with bcc structure were determined respectively as: [Ar] (3d c) 3.32 (3d n) 2.26 (4s c) 0.25 (4s f) 0.17 , [Kr] (4d c) 4.23 (4d n) 1.48 (5s c) 0.02 (5s f) 0.27 and [Xe](5d c) 5.16 (6s c) 0.25 (6s f) 0.59 .The electronic structures of these metals with hcp and fcc structures and liquid state were also studied. According to their electronic structures, the relationship between the electronic structure and crystalline structure was explained qualitatively and the relationship between the difference of mechanical properties and transport properties of pure Cr, Mo and W with bcc structure and their electronic structures was also explained qualitatively; the lattice constants, binding energy, potential curves, elasticities and the temperature dependence of the linear thermal expansion coefficient of bcc Cr, bcc Mo and bcc W were calculated quantitatively. 展开更多
关键词 CR MO W 电子结构 晶体结构 结合能 机械性能 转变特性
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On Dineutron and Deuteron Binding Energies
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作者 F. C. Hoh 《Journal of Modern Physics》 2021年第3期161-166,共6页
The binding energy of the deuteron is estimated from the scalar strong interaction hadron theory SSI. The predicted value is 7.7% lower than the measured value. Existence of a spin 1 dineutron with a binding energy 4/... The binding energy of the deuteron is estimated from the scalar strong interaction hadron theory SSI. The predicted value is 7.7% lower than the measured value. Existence of a spin 1 dineutron with a binding energy 4/5 that of the deuteron or 1.78 MeV is predicted. This is verified by the dineutron, first observed in 2012, in <sup>16</sup>Be decay. No free dineutrons are expected to exist in nature as they can decay into deuterons. These binding energies are limited by short range strong interaction internucleon forces but consist of long range electrostatic energies from quark charges. 展开更多
关键词 Scalar Strong Interaction Hadron Theory SSI Deuteron structure Dineutron structure Electromagnetic energy Deuteron binding energy Dineutron binding energy Dineutron Decay
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Structure-based discovery of orally efficient inhibitors via unique interactions with H-pocket of PDE8 for the treatment of vascular dementia 被引量:3
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作者 Xu-Nian Wu Qian Zhou +4 位作者 Ya-Dan Huang Xi Xie Zhe Li Yinuo Wu Hai-Bin Luo 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2022年第7期3103-3112,共10页
Our previous study demonstrated that phosphodiesterase 8(PDE8)could work as a potential target for vascular dementia(Va D)using a chemical probe 3a.However,compound 3a is a chiral compound which was obtained by chiral... Our previous study demonstrated that phosphodiesterase 8(PDE8)could work as a potential target for vascular dementia(Va D)using a chemical probe 3a.However,compound 3a is a chiral compound which was obtained by chiral resolution on HPLC,restricting its usage in clinic.Herein,a series of non-chiral 9-benzyl-2-chloro-adenine derivatives were discovered as novel PDE8 inhibitors.Lead 15 exhibited potent inhibitory activity against PDE8A(IC_(50)=11 nmol/L),high selectivity over other PDEs,and remarkable drug-like properties(worthy to mention is that its bioavailability was up to 100%).Oral administration of 15 significantly improved the c AMP level of the right brain and exhibited dosedependent effects on cognitive improvement in a Va D mouse model.Notably,the X-ray crystal structure of the PDE8A—15 complex showed that the potent affinity and high selectivity of 15 might come from the distinctive interactions with H-pocket including T-shapedπ—πinteractions with Phe785 as well as a unique H-bond network,which have never been observed in other PDE-inhibitor complex before,providing new strategies for the further rational design of novel selective inhibitors against PDE8. 展开更多
关键词 Phosphodiesterase 8(PDE8) Vascular dementia structure-based drug design MM-GB/SA Free energy prediction structure—activity relationship binding potencies
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Conformations and Metal Ion Affinities of Glutamine Binding with Alkali and Alkaline Earth Metal Cations: an ab initio Study
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作者 庞瑞 带子敬 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第2期189-199,I0004,共12页
Conformations and reaction energetics are important for understanding the interactions be- tween biomolecules and metal ions. In this work, we report a systematic ab initio study on the conformations and metal ion aff... Conformations and reaction energetics are important for understanding the interactions be- tween biomolecules and metal ions. In this work, we report a systematic ab initio study on the conformations and metal ion affinities of glutamine (Gln) binding with alkali and alkaline earth metal ions. An efficient and reliable method of searching low energy conformations of metalated Gln is proposed and applied to the complexes of Gln.Gln.M^+/++(M+/++=Li^+、Na^+、K^+、Rb^+、Cs^+、Be^++、Mg^++、Ca^++、Sr^++ and Ba^++).. In addition to all conformers known in literatures, many new important conformations are located, demonstrating the power of the new method and the necessity of the conformational search performed here. The metal coordination modes, relative energies, dipole moments, and equilibrium distributions of all important conformations of Gln.M^+/++ are calculated by the methods of B3LYP, BHandHLYP, and MP2. IR spectra and metalation enthalpies and free energies are also presented and compared with the available experiments. The results form an extensive database for systematic examination of the metalation properties of Gln. 展开更多
关键词 Conformational search method Complexation structure Conformational distribution IR spectrum binding energy
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Electronic structure of FCC phase in Fe-Mn-Si based shape memory alloys and its stability
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作者 万见峰 陈世朴 徐祖耀 《Science China(Technological Sciences)》 SCIE EI CAS 2001年第5期486-492,共7页
The relationship between the electronic structure of FCC phase in Fe?Mn?Si alloy and its stability has been studied by using the discrete variational method based on the first principle. The reason why Mn and Si eleme... The relationship between the electronic structure of FCC phase in Fe?Mn?Si alloy and its stability has been studied by using the discrete variational method based on the first principle. The reason why Mn and Si elements have different influences on the stacking fault energy may be related to the electron concentration (e/a). Si reduces the hole number of 3d band while Mn is rather complicated. The binding energy has been calculated and the experimental results that martensite start temperature (Ms) varies with SI and Mn are explained. When the external stress is exerted in three directions, the electronic structure, the total density of states, the energy gap at Fermi energy level(E F) and the energy degeneracy will change into other states. When the different external stresses are exerted in one direction, 3d or 4s orbital occupations of the central atom decrease, the partial density of states seems to be thinner and its peak increases atE F, the bond orbit shrinks in the direction of the external stress and another bond orbit comes out vertically. These lead to an a decrease in the structural stability and an increase In Ms temperature under the extemal stress. 展开更多
关键词 Fe-Mn-Si alloy electronic structure structural stability binding energy
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Synthesis,structure and radiative and nonradiative properties of a new Dy3+ complex with sulfonylamidophosphate ligand 被引量:2
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作者 Lukasz Marek Marcin Sobczyk +3 位作者 Victor A.Trush Kamil Korzeniowski Vladimir M.Amirkhanov Janina Legendziewicz 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第11期1255-1260,共6页
In recent years there has been growing interest in lanthanide-based multifunctional materials that exhibit interesting photophysical properties.This work presents spectroscopic and crystallographic characterization of... In recent years there has been growing interest in lanthanide-based multifunctional materials that exhibit interesting photophysical properties.This work presents spectroscopic and crystallographic characterization of a new dysprosium complex with sulfonylamidophosphate ligand.The crystal structure of[NaDy(SP)4]2·i-PrOH was determined and refined.It turns out that the Dy(Ⅲ)complex is not isostructural with earlier reported compounds and crystallizes in the monoclinic system(space group P21).Two crystallographically independent dysprosium atoms are in eight-fold coordination,with a triangular dodecahedron geometry.Absorption,emission(77 and 300 K)and excitation spectra as well as fluorescence decay time measurements allowed optical characterization of obtained complex.Efficient energy transfer from SP-ligand to Dy^3+ion has been demonstrated.The Judd-Ofelt theory was applied to predict fundamental fluorescence properties of Dy^3+ion in the title chelate.The Judd-Ofelt intensity parameters were used to determine the emission transition probabilities,fluorescence branching ratios and radiative lifetime of the emitting 4F9/2 level.The obtained results indicate that the investigated chelate can be a potential candidate for OLEDs emitting yellow light. 展开更多
关键词 DY^3+ Sulfonylamidophosphates Crystal structure Absorption and emission spectra Judd-Ofelt intensity calculations energy transfer
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印染行业碳排放分析及低碳发展建议
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作者 刘添涛 王翔 《印染助剂》 CAS 2024年第4期5-10,共6页
研究从印染行业的发展情况、能源结构、单位产品能耗、历史碳排放等情况,分析2025年、2030年及2035年的碳排放量,提出印染行业低碳发展建议。
关键词 碳排放 能源结构 低碳 印染
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Electronic structure of YMn2O5 studied by EELS and first-principles calculations
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作者 Zhen Chen Rui-Juan Xiao +8 位作者 Chao Ma Yuan-Bin Qin Hong-Long Shi Zhi-Wei Wang Yuan-Jun Song Zhen Wang Huan-Fang Tian Huai-Xin Yang Jian-Qi Li 《Frontiers of physics》 SCIE CSCD 2012年第4期429-434,共6页
The electronic structure of multiferroic YMn2O5 material has been studied by use of the generalized gradient approximation (GGA). The results demonstrate that the oxygen 2p and manganese 3d orbitals are strongly hyb... The electronic structure of multiferroic YMn2O5 material has been studied by use of the generalized gradient approximation (GGA). The results demonstrate that the oxygen 2p and manganese 3d orbitals are strongly hybridized. Considering the on-site Coulomb interaction U, we performed the GGA+U calculations for 0 〈 U ≤8 eV, and it is found that the increase of U could enlarge the band gap and, on the other hand, weaken the Mn-O hybridization. The experimental measurements of the electron energy-loss spectrometry (EELS) exhibit a rich variety of structural features in both O-K edge and Mn-L edges. A theoretical and experimental analysis on the O-K edge suggests that the on-site Coulomb interaction (U) in YMn2O5 could be less than 4 eV. Certain electronic structural features of LaMn2O5 have been discussed in comparison with those of YMn2O5. 展开更多
关键词 YMn2O5 MULTIFERROICS electron energy-loss spectra electronic structure GGA+U
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