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Controlled Teleportation of an Arbitrary Two-Particle State by One EPR Pair and Cluster State 被引量:3
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作者 郭战营 尚晓星 +1 位作者 方建兴 肖瑞华 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第11期819-823,共5页
A scheme for controlled teleportation of an arbitrary two-particle state using a maximally entangled EPR pair and a cluster state as the quantum channel is proposed. After receiving Alice's Bell state measurement res... A scheme for controlled teleportation of an arbitrary two-particle state using a maximally entangled EPR pair and a cluster state as the quantum channel is proposed. After receiving Alice's Bell state measurement results, the controller performs a joint measurement on his particles under a non-maximally entangled Bell-basis. The receiver needs to introduce an auxiliary qubit, and performs a series of appropriate unitary transformations on his particles. The original state can be teleported successfully with the probability 2 cos2θ. 展开更多
关键词 controlled teleportation arbitrary two-particle state cluster state unitary transformation
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Density Functional Theory Study on Electronic and Magnetic Properties of Mn-doped (MgO)n (n=2-10) Clusters
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作者 王鹏 杨明霞 +2 位作者 张胜利 黄世萍 田辉平 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第1期35-42,I0003,共9页
We study the geometries, stabilities, electronic and magnetic properties of (MgO)n (n=2-10) clusters doped with a single Mn atom using the density functional theory with the gener- alized gradient approximation. T... We study the geometries, stabilities, electronic and magnetic properties of (MgO)n (n=2-10) clusters doped with a single Mn atom using the density functional theory with the gener- alized gradient approximation. The optimized geometries show that the impurity Mn atom prefers to replace the Mg atom which has low coordination number in all the lowest-energy MnMgn-1On (n=2-10) structures. The stability analysis clearly represents that the average binding energies of the doped clusters are larger than those of the corresponding pure (MgO)n clusters. Maximum peaks of the second order energy differences are observed for MnMg~_1On clusters at n=6, 9, implying that these clusters exhibit higher stability than their neighboring clusters. In addition, all the Mn-doped Mg clusters exhibit high total magnetic moments with the exception of MnMgO2 which has 3.00μB. Their magnetic behavior is attributed to the impurity Mn atom, the charge transfer modes, and the size of MnMgn- 1On clusters. 展开更多
关键词 Density functional theory MnMgn-1On cluster Electronic property MAGNETICPROPERTY
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Grey Clustering Theory to Assess the Effect of Mineral Admixtures on the Cyclic Sulfate Resistance of Concrete 被引量:3
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作者 袁晓露 李北星 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第2期316-318,共3页
Concrete specimens made with ordinary portland cement or ordinary portland cement incorporating fly ash with the replacement of 10% or 20%, ground blast furnace slag with the replacement of 15% or 30%, or 15% fly ash ... Concrete specimens made with ordinary portland cement or ordinary portland cement incorporating fly ash with the replacement of 10% or 20%, ground blast furnace slag with the replacement of 15% or 30%, or 15% fly ash and 15% ground blast furnace slag were made and exposed to a cyclic sulfate environment. Concrete properties including relative dynamic elastic modulus, chloride ion diffusion coefficient, compressive strength and flexural strength were measured. Effect of mineral admixtures on the cyclic sulfate resistance of concrete was assessed based on the grey clustering theory. The experimental results indicate that the cyclic sulfate resistance of concrete incorporating ground blast furnace slag belongs to the higher grey grade, which exhibits that it possesses excellent cyclic sulfate resistance. With increasing addition of fly ash, the cyclic sulfate resistance of concrete changes from the medium grey grade to the lower grey grade, which shows that incorporation of fly ash is disadvantageous for the cyclic sulfate resistance of concrete. 展开更多
关键词 cyclic sulfate resistance grey clustering theory mineral admixtures CONCRETE
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Autonomous Clustering Using Rough Set Theory 被引量:2
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作者 Charlotte Bean Chandra Kambhampati 《International Journal of Automation and computing》 EI 2008年第1期90-102,共13页
This paper proposes a clustering technique that minimizes the need for subjective human intervention and is based on elements of rough set theory (RST). The proposed algorithm is unified in its approach to clusterin... This paper proposes a clustering technique that minimizes the need for subjective human intervention and is based on elements of rough set theory (RST). The proposed algorithm is unified in its approach to clustering and makes use of both local and global data properties to obtain clustering solutions. It handles single-type and mixed attribute data sets with ease. The results from three data sets of single and mixed attribute types are used to illustrate the technique and establish its efficiency. 展开更多
关键词 Rough set theory (RST) data clustering knowledge-oriented clustering AUTONOMOUS
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Density functional theory study of Mg_nNi_2(n=1-6) clusters 被引量:2
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作者 李晶 刘小勇 +1 位作者 朱正和 盛勇 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第3期151-157,共7页
The geometries of MgnNi2(n = 1 6) clusters are studied by using the hybrid density functional theory (B3LYP) with LANL2DZ basis sets. For the ground-state structures of MgnNi2 clusters, the stabilities and the ele... The geometries of MgnNi2(n = 1 6) clusters are studied by using the hybrid density functional theory (B3LYP) with LANL2DZ basis sets. For the ground-state structures of MgnNi2 clusters, the stabilities and the electronic properties are investigated. The results show that the groundstate structures and symmetries of Mg clusters change greatly due to the Ni atoms. The average binding energies have a growing tendency while the energy gaps have a declining tendency. In addition, the ionization energies exhibit an odd-even oscillation feature. We also conclude that n = 3, 5 are the magic numbers of the MgnNi2 clusters. The Mg3Ni2 and Mg5Ni2 clusters are more stable than neighbouring clusters, and the MgaNi2 cluster exhibits a higher chemical activity. 展开更多
关键词 MgnNi2 clusters density functional theory geometrical structures STABILITY
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Theory Study of the Adsorption of Hydrocyanic Acid onto Small Silver Clusters 被引量:2
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作者 胡建明 王大川 +2 位作者 赵勇刚 李奕 章永凡 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第2期228-236,共9页
Density functional theory calculations have been performed to study the interaction of small silver clusters, Ag2-Ag9, with HCN. The adsorption of HCN on-top site of the silver cluster, among various possible sites, i... Density functional theory calculations have been performed to study the interaction of small silver clusters, Ag2-Ag9, with HCN. The adsorption of HCN on-top site of the silver cluster, among various possible sites, is energetically preferred. The adsorption energies of HCN on the silver clusters reach a local maximum at n = 4, which is only about 0.450 eV, indicating that the adsorbed HCN molecule is weakly perturbed. The adsorbed C-N and C-H stretching frequencies are blue- and red-shifted compared with the values of free HCN, respectively. 展开更多
关键词 density functional theory HCN ADSORPTION silver clusters
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Density Functional Theory Study on the Adsorption of Dioxygen on Small Pt-Pd Clusters 被引量:1
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作者 李钠 官文佳 +3 位作者 王艳丽 马琳 孙仁安 孙公权 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第1期63-78,共16页
The electronic and physical properties of PtmPdn (m+n≤5) metal clusters and their interactions with dioxygen have been studied by using hybrid density functional B3LYP method. The total energies, atomization energ... The electronic and physical properties of PtmPdn (m+n≤5) metal clusters and their interactions with dioxygen have been studied by using hybrid density functional B3LYP method. The total energies, atomization energies, vibration frequencies, and charge distributions were reported. The Pt-Pt bridge site modified by Pd atoms was found to be the most active site for the dissociation of dioxygen, which was mainly due to the change of electronic structures of the Pt atoms in bimetallic Pt-Pd clusters. 展开更多
关键词 clusterS bridge site charge transfer density functional theory method
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Computational Investigation of Neutral and Anionic Al_nCo_m Clusters by Density-functional Theory 被引量:1
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作者 赵晋婧 郭玲 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第5期816-824,共9页
Structural and electronic properties of bimetallic clusters AlnCom with n=1~7 and m=1~2 have been investigated using the B3LYP-DFT method.Structural optimization and frequency analysis were performed at the CEP-121G... Structural and electronic properties of bimetallic clusters AlnCom with n=1~7 and m=1~2 have been investigated using the B3LYP-DFT method.Structural optimization and frequency analysis were performed at the CEP-121G level.The charge-induced structural changes in these anions were discussed.In addition,the corresponding total energies,binding energies,adiabatic electron affinities and vertical electron affinity were also presented and discussed.Our predicted vertical ionization potentials are in reasonable agreement with the experimental ionization potentials.Among different AlnCom and AlnCom-anions (n=1~7,m=1~2),Al4Co,Al6Co,Al4Co-,Al6Co-and Al4Co2-are predicted to be species with high stabilities. 展开更多
关键词 density functional theory bimetallic aluminumcobalt clusters CEP-121G level stability
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Density functional theory study on the structure and properties of Si3N4 clusters 被引量:3
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作者 ZHANG Cai-rong ZHANG Bi-xia +2 位作者 CHEN Yu-hong LI Wei-xue XU Guang-ji 《原子与分子物理学报》 CAS CSCD 北大核心 2006年第B04期171-174,共4页
关键词 硅氮化物 结构 特性 密度函数理论
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Using genetic algorithm based fuzzy adaptive resonance theory for clustering analysis 被引量:3
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作者 LIU Bo WANG Yong WANG Hong-jian 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2006年第B07期547-551,共5页
关键词 聚类分析 遗传算法 模糊自适应谐振理论 人工神经网络
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ENTROPIC CONTRIBUTION TO THE INTERACTION PARAMETER x IN THE POLYMER/OLIGOMER SYSTEM:A LATTICE CLUSTER THEORY CONSIDERATION
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作者 Dong-shanZhou Xiao-liangWang BoChe LiangLi Jin-luChen GiXue 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2005年第2期159-163,共5页
Entropic contribution to the interaction parameter (?) in the model incompressible polymer/oligomer system iscalculated by the lattice cluster theory(LCT).It is found that in the oligomer solvent,there exists a wide c... Entropic contribution to the interaction parameter (?) in the model incompressible polymer/oligomer system iscalculated by the lattice cluster theory(LCT).It is found that in the oligomer solvent,there exists a wide concentration rangethat the non-combinatorial“entropic interaction”term (?)φ_1φ_2 perceptibly counteracts the mean field combinary entropy△S_(MF).With the increase of the solvent size,both (?) and the ratio (?)φ_1φ_2/△S_(MF) first reach their maximum and finallybecome trivially to zero.It is worth noting that no any demixing was found in the current calculation.This makes thecontroversial idea“entropically driven demixing”even elusive.However,we propose that further work on compressiblepolymer solution with structured monomer will witness the demixing owning to an increased configurational correlation. 展开更多
关键词 Lattice cluster theory ENTROPY OLIGOMER Interaction parameter Demixing.
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Structures and electronic properties of Si_m N_(8-m)(0
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作者 张材荣 陈玉红 +2 位作者 王道斌 吴有智 陈宏善 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第8期2938-2950,共13页
The geometries, electronic structures and related properties of SimN8-m(0 〈 m 〈 8) clusters are studied using density functional theory (DFT) with hybrid functional B3LYP. The calculated results reveal several t... The geometries, electronic structures and related properties of SimN8-m(0 〈 m 〈 8) clusters are studied using density functional theory (DFT) with hybrid functional B3LYP. The calculated results reveal several trends. For any stoichiometric clusters, the lowest energy isomers with an alteration of N and Si atoms are favourable in energy if the numbers of Si and N atoms are large enough to form ... Si N-Si-N... alternative chains. The bond lengths of single Si-N bonds are very close to the corresponding values of the bulk and other SiN clusters. The geometries for N-rich and Si4N4 clusters are planar structures, but three-dimensional structures are favourable in energy for Si-rich clusters. With the increase of m, the isotropic polarizability and average polarizability increase, the total binding energies generally decrease, the HOMO-LUMO gap and vertical ionization potential oscillate with increasing number of valence electrons, and their values with even valence electrons are larger than those with odd valence electrons. The atomic charges, IR and Raman properties are also reported. 展开更多
关键词 cluster structure and properties density functional theory silicon nitride
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Density Functional Theory Study of HCN Adsorption on Small Gold Clusters
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作者 郭冰青 胡建明 +2 位作者 李奕 章永凡 李俊篯 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第11期1490-1496,共7页
A theoretical study was carried out on the adsorption of hydrocyanic acid on small Aun (n ≤ 7) clusters using density functional methods. For HCN adsorption on gold clusters, no dependence was found with respect to... A theoretical study was carried out on the adsorption of hydrocyanic acid on small Aun (n ≤ 7) clusters using density functional methods. For HCN adsorption on gold clusters, no dependence was found with respect to the even-odd alternation in relation to the number of gold atoms in the cluster. The HCN molecule is adsorbed at simple adsorption sites (1-fold coordination), perpendicular to the adsorption site. The largest adsorption energy is only about 74.61 kJ·mol^-1, which indicates that the HCN molecule does not decompose and the C-N bond retains triple bond, and that the C-H and C-N stretching frequencies are only weakly perturbed. The adsorbed C-N and C-H stretching frequencies are blue- and red-shifted compared with the values of free HCN, respectively. 展开更多
关键词 density functional theory ADSORPTION HCN Au clusters
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Study on electronic density topology of various cluster models of Mg/Al hydrotalcite by density functional theory
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作者 Renqing Lu Nina Zhang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第2期179-184,共6页
The geometry and electronic topology properties of Mg/Al hydrotalcite cluster models were comparatively investigated by means of density functional theory at GGA/DND levels.The results suggested that cluster model con... The geometry and electronic topology properties of Mg/Al hydrotalcite cluster models were comparatively investigated by means of density functional theory at GGA/DND levels.The results suggested that cluster model containing seven octahedral cations was the smallest size to be employed to simulate other properties.The fact that the n+ charge of cluster models containing n aluminum atoms can reflect electronic properties of anionic clay layer sheet.The bond lengths of clusters can be modified by terminating with or without OH-/H2O groups in terms of principle of bond order conservation. 展开更多
关键词 HYDROTALCITE density functional theory cluster model Mg/Al
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Density functional theory study of neutral AlS_n(n=2-9) clusters
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作者 李听昕 王林 +3 位作者 王飞 陈军 姜振益 李莉莎 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第3期135-142,共8页
This paper investigates the geometrical structures and relative stabilities of neutral A1Sn (n=2-9) using the density functional theory. Structural optimisation and frequency analysis are performed at the B3LYP/6-3... This paper investigates the geometrical structures and relative stabilities of neutral A1Sn (n=2-9) using the density functional theory. Structural optimisation and frequency analysis are performed at the B3LYP/6-311C(d) level. The ground state structures of the A1Sn show that the sulfur atoms prefer not only to evenly distribute on both sides of the aluminum atom but also to form stable structures in AlSn clusters. The structures of pure Sn are fundamentally changed due to the doping of the Al atom. The fragmentation energies and the second-order energy differences are calculated and discussed. Among neutral AlSn (n = 2-9) clusters, AlS4 and AlS6 are the most stable. 展开更多
关键词 aluminum sulfur clusters density functional theory structure and stability energy
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Isomers of the Cu_5 cluster:a density function theory study
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作者 龚恒风 李公平 贾艳辉 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第3期164-169,共6页
In this work, a systematic study of some possible isomer structures of the Cu5 cluster obtained from density functional theory methods is presented. The polarisation and pseudopotential basis sets are employed in the ... In this work, a systematic study of some possible isomer structures of the Cu5 cluster obtained from density functional theory methods is presented. The polarisation and pseudopotential basis sets are employed in the calculations. The results show that the binding energies, frequencies, coordination numbers and average bond lengths are in reasonable agreement with reported experimental data. Moreover, four isomers of the Cu5 cluster are obtained according to calculations, in which the most stable configuration is the planar structure. Meanwhile, two three-dimensional structures of the Cu5 cluster are obtained in this work, which might be valuable for further theoretical and experimental studies. In addition, our study proves the possibility of the isomer structures of the Cu5 cluster. 展开更多
关键词 density function theory Cu5 cluster isomer structure
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A density-functional theory for (BAs) n clusters (n=1-14):structures,stabilities and electronic properties
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作者 刘志锋 雷雪玲 +2 位作者 刘立仁 刘火雁 祝恒江 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第2期201-208,共8页
This paper investigates the lowest-energy structures, stabilities and electronic properties of (BAs)n clusters (n=1- 14) by means of the density-functional theory. The results show that the lowest-energy structure... This paper investigates the lowest-energy structures, stabilities and electronic properties of (BAs)n clusters (n=1- 14) by means of the density-functional theory. The results show that the lowest-energy structures undergo a structural change from two-dimensional to three-dimensional when n : 4. With the increase of the cluster size (n=6), the (BAs)n clusters tend to adopt cage-like structures, which can be considered as being built from B2As2 and six-membered rings with B-As bond alternative arrangement. The binding energy per atom, second-order energy differences, vertical electron affinity and vertical ionization potential are calculated and discussed. The caculated HOMO-LUMO gaps reveal that the clusters have typical semiconductor characteristics. The analysis of partial density of states suggests that there are strong covalence and molecular characteristics in the clusters. 展开更多
关键词 (BAs)n clusters density-functional theory lowest-energy structures electronic proper-ties
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Ultraviolet laser ionization studies of 1-fluoronaphthalene clusters and density functional theory calculations
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作者 张树东 张海芳 曾文碧 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期223-227,共5页
This paper studies supersonic jet-cooled 1-fluoronaphthalene (1FN) clusters by ultraviolet (UV) laser ionization at 281 nm in a time-of-flight mass spectrometer. The (1FN)+ (n=1-3) series cluster ions are obs... This paper studies supersonic jet-cooled 1-fluoronaphthalene (1FN) clusters by ultraviolet (UV) laser ionization at 281 nm in a time-of-flight mass spectrometer. The (1FN)+ (n=1-3) series cluster ions are observed where the signal intensity decreases with increasing cluster size. The effects of sample inlet pressures and ionization laser fluxes to mass spectral distribution are measured. Using density functional theory calculations, it obtains a planar geometric structure of 1FN dimer which is combined through two hydrogen bonds. The mass spectra indicate that the intensity of 1FN trimer is much weaker than that of 1FN dimer and this feature is attributed to the fact that the dimer may form the first "shell" in geometric structure while the larger clusters are generated based on this fundamental unit. 展开更多
关键词 1-fluoronaphthalene clusters ultraviolet laser ionization mass spectrum density functional theory calculation
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Density functional theory study on Ni-doped Mg_n Ni(n=17) clusters
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作者 陈雪风 张岩 +3 位作者 齐凯天 李兵 朱正和 盛勇 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第3期288-292,共5页
The possible geometrical and the electronic structures of small MgnNi (n = 1 - 7) clusters are optimised by the density functional theory with a LANL2DZ basis set. The binding energy, the energy gap, the electron af... The possible geometrical and the electronic structures of small MgnNi (n = 1 - 7) clusters are optimised by the density functional theory with a LANL2DZ basis set. The binding energy, the energy gap, the electron affinity, the dissociation energy and the second difference in energy are calculated and discussed. The properties of MgnNi clusters are also discussed when the number of Mg atom increases. 展开更多
关键词 density functional theory magnesium nickel clusters structure of ground state
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A density functional theory structures, stabilities, and study on size-dependent electronic properties of bimetallic MnAgm (M=Na, Li; n + m ≤ 7) clusters
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作者 孙浩然 邝小渝 +2 位作者 李艳芳 邵鹏 赵亚儒 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第8期202-210,共9页
The equilibrium geometries, relative stabilities, and electronic properties of MnAgm(M=Na, Li; n + m ≤ 7) as well as pure Agn, Nan, Lin (n ≤ 7) clusters are systematically investigated by means of the density f... The equilibrium geometries, relative stabilities, and electronic properties of MnAgm(M=Na, Li; n + m ≤ 7) as well as pure Agn, Nan, Lin (n ≤ 7) clusters are systematically investigated by means of the density functional theory. The optimized geometries reveal that for 2 ≤ n ≤ 7, there are significant similarities in geometry among pure Agn, Nan, and Lin clusters, and the transitions from planar to three-dimensional configurations occur at n = 7, 7, and 6, respectively. In contrast, the first three-dimensional (3D) structures are observed at n + m = 5 for both NanAgm and LinAgm clusters. When n + m ≥5, a striking feature is that the trigonal bipyramid becomes the main subunit of LinAgm. Furthermore, dramatic odd-even alternative behaviours are obtained in the fragmentation energies, secondorder difference energies, highest occupied and lowest unoccupied molecular orbital energy gaps, and chemical hardness for both pure and doped clusters. The analytic results exhibit that clusters with an even electronic configuration (2, 4, 6) possess the weakest chemical reactivity and more enhanced stability. 展开更多
关键词 MnAgm (M=Na Li) clusters density functional theory relative stability
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