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Deep brain implantable microelectrode arrays for detection and functional localization of the subthalamic nucleus in rats with Parkinson’s disease 被引量:1
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作者 Luyi Jing Zhaojie Xu +11 位作者 Penghui Fan Botao Lu Fan Mo Ruilin Hu Wei Xu Jin Shan Qianli Jia Yuxin Zhu Yiming Duan Mixia Wang Yirong Wu Xinxia Cai 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期439-452,共14页
The subthalamic nucleus(STN)is considered the best target for deep brain stimulation treatments of Parkinson’s disease(PD).It is difficult to localize the STN due to its small size and deep location.Multichannel micr... The subthalamic nucleus(STN)is considered the best target for deep brain stimulation treatments of Parkinson’s disease(PD).It is difficult to localize the STN due to its small size and deep location.Multichannel microelectrode arrays(MEAs)can rapidly and precisely locate the STN,which is important for precise stimulation.In this paper,16-channel MEAs modified with multiwalled carbon nanotube/poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(MWCNT/PEDOT:PSS)nanocomposites were designed and fabricated,and the accurate and rapid identification of the STN in PD rats was performed using detection sites distributed at different brain depths.These results showed that nuclei in 6-hydroxydopamine hydrobromide(6-OHDA)-lesioned brains discharged more intensely than those in unlesioned brains.In addition,the MEA simultaneously acquired neural signals from both the STN and the upper or lower boundary nuclei of the STN.Moreover,higher values of spike firing rate,spike amplitude,local field potential(LFP)power,and beta oscillations were detected in the STN of the 6-OHDA-lesioned brain,and may therefore be biomarkers of STN localization.Compared with the STNs of unlesioned brains,the power spectral density of spikes and LFPs synchronously decreased in the delta band and increased in the beta band of 6-OHDA-lesioned brains.This may be a cause of sleep and motor disorders associated with PD.Overall,this work describes a new cellular-level localization and detection method and provides a tool for future studies of deep brain nuclei. 展开更多
关键词 functional localization Implantable microelectrode arrays Parkinson’s disease Subthalamic nucleus
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Functional localization of the cortical motor area in the brain Electrocorticogram analysis
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作者 Tao Jiang Xiaoming Wu Binggang Ye Sijuan Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第19期1480-1485,共6页
The method for rapidly, precisely and non-invasively localizing functional regions of the brain is a problem in neuromedicine research. Cortical electrostimulation is the optimal localization method during brain surge... The method for rapidly, precisely and non-invasively localizing functional regions of the brain is a problem in neuromedicine research. Cortical electrostimulation is the optimal localization method during brain surgery, with a degree of accuracy of approximately 5 mm. However, electrostimulation can damage the cerebral cortex, trigger epilepsy, and extend the operation time. Studies are required to determine whether cortical motor regions can be localized by wavelet analysis from electrocorticograms. In this study, based on wavelet analysis of electrocorticograms, a selection of algorithms for classification of the mu rhythm in the motor regions utilizing experimental data was verified. Results demonstrated that a characteristic quantity of energy ratio in the reconstructed signal was filtered in the d6 (7.81-15.62 Hz) band prior to and following motion events. A characteristic threshold was considered to be 40%. The accuracy of localization detection was 93%. The degree of accuracy was less than 5 mm. The present study avoided the problems of cerebral cortex injury and epilepsy onset, with an operation time of 60 seconds. Therefore, wavelet analysis on electrocorticogram is feasible for localizing cortical motor regions. Furthermore, this localization technique is accurate, safe and rapid. 展开更多
关键词 functional localization ELECTROCORTICOGRAM mu rhythm event-related desynchronization wavelet analysis neural regeneration
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LOCAL C-SEMIGROUPS AND LOCAL C-COSINE FUNCTIONS 被引量:1
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作者 高明杵 《Acta Mathematica Scientia》 SCIE CSCD 1999年第2期201-213,共13页
This paper is concerned with the local C-semigroups and local C-cosine functions without the assumption that the image of C is dense in a Banach space X, First, the sufficient and necessary conditions for a local C-se... This paper is concerned with the local C-semigroups and local C-cosine functions without the assumption that the image of C is dense in a Banach space X, First, the sufficient and necessary conditions for a local C-semigroup and a C-cosine function to be the restriction of a global C-semigroup and a global C-cosine function to an interval are given, respectively, Secondly, it is characterized for a closed operator to be the generator of a local C-semigroup and a local C-cosine function, respectively. 展开更多
关键词 local C-semigroups local C-cosine functions asymptotic C-resolvent
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Changes in sensorimotor regions of the cerebral cortex in congenital amusia:a case-control study 被引量:1
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作者 Jun-Jie Sun Xue-Qun Pan +4 位作者 Ru Yang Zhi-Shuai Jin Yi-Hui Li Jun Liu Da-Xing Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第3期531-536,共6页
Perceiving pitch is a central function of the human auditory system;congenital amusia is a disorder of pitch perception.The underlying neural mechanisms of congenital amusia have been actively discussed.However,little... Perceiving pitch is a central function of the human auditory system;congenital amusia is a disorder of pitch perception.The underlying neural mechanisms of congenital amusia have been actively discussed.However,little attention has been paid to the changes in the motor rain within congenital amusia.In this case-control study,17 participants with congenital amusia and 14 healthy controls underwent functional magnetic resonance imaging while resting with their eyes closed.A voxel-based degree centrality method was used to identify abnormal functional network centrality by comparing degree centrality values between the congenital amusia group and the healthy control group.We found decreased degree centrality values in the right primary sensorimotor areas in participants with congenital amusia relative to controls,indicating potentially decreased centrality of the corresponding brain regions in the auditory-sensory motor feedback network.We found a significant positive correlation between the degree centrality values and the Montreal Battery of Evaluation of Amusia scores.In conclusion,our study identified novel,hitherto undiscussed candidate brain regions that may partly contribute to or be modulated by congenital amusia.Our evidence supports the view that sensorimotor coupling plays an important role in memory and musical discrimination.The study was approved by the Ethics Committee of the Second Xiangya Hospital,Central South University,China(No.WDX20180101GZ01)on February 9,2019. 展开更多
关键词 congenital amusia degree centrality lifelong impairment local functional connectivity music discrimination primary motor area primary sensorimotor area primary sensory area resting-state functional magnetic resonance imaging voxel-based analysis
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MULTI-SCALE COHERENT STRUCTURES IN TURBULENT BOUNDARY LAYER DETECTED BY LOCALLY AVERAGED VELOCITY STRUCTURE FUNCTIONS 被引量:1
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作者 刘建华 姜楠 +1 位作者 王振东 舒玮 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第4期495-504,共10页
The time sequence of longitudinal velocity component at different vertical locations in turbulent boundary layer was finely measured in a wind tunnel. The concept of coarse_grained velocity structure functions, which ... The time sequence of longitudinal velocity component at different vertical locations in turbulent boundary layer was finely measured in a wind tunnel. The concept of coarse_grained velocity structure functions, which describes the relative motions of straining and compressing for multi_scale eddy structures in turbulent flows, was put forward based on the theory of locally multi_scale average. Based on the consistency between coarse_grained velocity structure function and Harr wavelet transformation,detecting method was presented, by which the coherent structures and their intermittency was identified by multi_scale flatness factor calculated by locally average structure function. Phase_averaged evolution course for multi_scale coherent eddy structures in wall turbulence were extracted by this conditional sampling to educe scheme. The dynamics course of multi_scale coherent eddy structures and their effects on statistics of turbulent flows were studied. 展开更多
关键词 turbulent boundary layer coherent structure flatness factor intermittency locally averaged velocity structure function
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Density Function Theory Study on the Reaction Mechanism of Cerium with Oxygen for Ce-bearing Aerosol Particle Formation
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作者 XIE Bo WANG Qingqing +2 位作者 LONG Xinggui HU Sheng GAO Tao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第3期501-505,共5页
We obtained the reaction mechanism of cerium with oxygen by means of density functional theory (DFT) under the explosive or detonation situation. The energy level order of cerium was calculated and the potential energ... We obtained the reaction mechanism of cerium with oxygen by means of density functional theory (DFT) under the explosive or detonation situation. The energy level order of cerium was calculated and the potential energy profile was plotted. The properties of the bonds of all special structures in the reaction path were analyzed using the method of the electron localization function (ELF). The results indicate that the final reaction pathway can be expressed as Ce+O2→ FC→TS→IM→O-Ce-O, and the formation of Ce2O3 has not been found. In addition, the ELF diagram of the final product CeO2 shows that Ce bonds with both O atoms and the bond angles increase significantly. 展开更多
关键词 Ce oxidation reaction mechanism electronic localized function aerosol particles
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Density function theoretical study on the complex involved in Th atom-activated C–C bond in C2H6
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作者 王青青 李鹏 +2 位作者 高涛 王红艳 敖冰云 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第6期172-178,共7页
Density functional theory(DFT) calculations are performed to investigate the reactivity of Th atom toward ethane C–C bond activation.A comprehensive description of the reaction mechanisms leading to two different r... Density functional theory(DFT) calculations are performed to investigate the reactivity of Th atom toward ethane C–C bond activation.A comprehensive description of the reaction mechanisms leading to two different reaction products is presented.We report a complete exploration of the potential energy surfaces by taking into consideration different spin states.In addition,the intermediate and transition states along the reaction paths are characterized.Total,partial,and overlap population density of state diagrams and analyses are also presented.Furthermore,the natures of the chemical bonding of intermediate and transition states are studied by using topological method combined with electron localization function(ELF) and Mayer bond order.Infrared spectrum(IR) is obtained and further discussed based on the optimized geometries. 展开更多
关键词 reaction mechanism Mayer bond order electron localization function density of states
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On the Bonding Nature of Noble Gas Compounds MRg^(+) and MRgF(M=Co,Rh,Ir;Rg=Ar,Kr,Xe)
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作者 Si-yuan Xian Di-hao Tan An-yong Li 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第3期297-308,I0039-I0043,I0047,共18页
The structure and stability of the compounds MRg^(+)and MRg F(Rg=Ar,Kr,and Xe;M=Co,Rh,and Ir)were investigated using the B3 LYP,MP2,MP4(SDQ)and CCSD(T)methods.We reported the geometry,vibrational frequencies and therm... The structure and stability of the compounds MRg^(+)and MRg F(Rg=Ar,Kr,and Xe;M=Co,Rh,and Ir)were investigated using the B3 LYP,MP2,MP4(SDQ)and CCSD(T)methods.We reported the geometry,vibrational frequencies and thermodynamics properties of these compounds.A series of theoretical methods on the basis of wavefunction analysis,including natural bond orbitals,atoms in molecules,electron localization function,and energy decomposition analysis,were performed to explore bonding nature of the M-Rg and Rg-F bonds.These bonds are mainly noncovalent,the metal weakly interacts with Rg in MRg^(+),but their interaction is much stronger in MRg F.The neutral molecule MRg F can be well described by the Lewis structure[MRg]^(+)F^(-). 展开更多
关键词 Rare gases CO RH IR Bond nature Natural bond orbitals Atom in molecules analyses Electron localization function analyses
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Superconductivity in electron-doped arsenene
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作者 Xin Kong Miao Gao +2 位作者 Xun-Wang Yan Zhong-Yi Lu Tao Xiang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第4期127-133,共7页
Based on the first-principles density functional theory electronic structure calculation,we investigate the possible phonon-mediated superconductivity in arsenene,a two-dimensional buckled arsenic atomic sheet,under e... Based on the first-principles density functional theory electronic structure calculation,we investigate the possible phonon-mediated superconductivity in arsenene,a two-dimensional buckled arsenic atomic sheet,under electron doping.We find that the strong superconducting pairing interaction results mainly from the pz-like electrons of arsenic atoms and the A1 phonon mode around the K point,and the superconducting transition temperature can be as high as 30.8 K in the arsenene with 0.2 doped electrons per unit cell and 12%-applied biaxial tensile strain.This transition temperature is about ten times higher than that in the bulk arsenic under high pressure.It is also the highest transition temperature that is predicted for electron-doped two-dimensional elemental superconductors,including graphene,silicene,phosphorene,and borophene. 展开更多
关键词 arsenene phonon-mediated superconductivity first-principles calculation maximally localized Wannier functions
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Inverted V-shaped evolution of superconducting temperature in SrBC under pressure
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作者 Ru-Yi Zhao Xun-Wang Yan Miao Gao 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第7期413-419,共7页
Based on density functional first-principles calculations and anisotropic Eliashberg equations,we have investigated the electronic structure,lattice dynamics,and phonon-mediated superconductivity in newly synthesized ... Based on density functional first-principles calculations and anisotropic Eliashberg equations,we have investigated the electronic structure,lattice dynamics,and phonon-mediated superconductivity in newly synthesized layered compound Sr BC under pressure.Different from Li BC and Mg B2,our calculations surprisingly reveal that Sr BC is isotropic in compressibility,due to the accumulation of substantial electrons in the interstitial region.We find that the Sr phonons strongly couple with B-2 pz orbital and the interstitial states,giving rise to a two-gap superconductivity in Sr BC,whose transition temperature shows an inverted V-shaped dependence on pressure.The maximal transition temperature is about 22 K at50 GPa.On both sides of 50 GPa,the transition temperature exhibits quasi-linear variation with positive and negative slopes,respectively.Such a variation of transition temperature is infrequent among phonon-mediated superconductors.The competition between enhanced electron–phonon matrix element and hardened phonons plays an essential role in governing the behavior of the critical temperature. 展开更多
关键词 SrBC phonon-mediated superconductivity anisotropic Eliashberg theory first-principles calculation maximally localized Wannier functions
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SEMILINEAR HEMIVARIATIONAL INEQUALITIES WITH STRONG RESONANCE AT INFINITY
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作者 Michael Filippakis Leszek Gasi■ski Nikolaos S.Papageorgiou 《Acta Mathematica Scientia》 SCIE CSCD 2006年第1期59-73,共15页
A semilinear elliptic equation with strong resonance at infinity and with a nonsmooth potential is studied. Using nonsmooth critical point theory and developing some abstract minimax principles which complement and ex... A semilinear elliptic equation with strong resonance at infinity and with a nonsmooth potential is studied. Using nonsmooth critical point theory and developing some abstract minimax principles which complement and extend results in the literature, two results on existence are obtained. 展开更多
关键词 Strong resonance hemivariational inequality LAPLACIAN principal eigenvalue locally Lipschitz function Clarke subdifferential nonsmooth criticalpoint theory
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Differentiability of Convex Functions in Locally Convex Spaces(Ⅱ)──Frechet
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作者 王晓敏 程立新 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第1期1-4,共4页
DifferentiabilityofConvexFunctionsinLocallyConvexSpaces(II)──FrechetDifferentiabilityWUCongxinWANGXiaominCHE... DifferentiabilityofConvexFunctionsinLocallyConvexSpaces(II)──FrechetDifferentiabilityWUCongxinWANGXiaominCHENGLixin吴从aaay,王晓敏... 展开更多
关键词 王晓 Differentiability of Convex Functions in Locally Convex Spaces Frechet
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ADDITIVE HAZARDS MODEL WITH TIME-VARYING REGRESSION COEFFICIENTS
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作者 黄彬 《Acta Mathematica Scientia》 SCIE CSCD 2010年第4期1318-1326,共9页
This article discusses regression analysis of failure time under the additive hazards model, when the regression coefficients are time-varying. The regression coefficients are estimated locally based on the pseudo-sco... This article discusses regression analysis of failure time under the additive hazards model, when the regression coefficients are time-varying. The regression coefficients are estimated locally based on the pseudo-score function [12] in a window around each time point. The proposed method can be easily implemented, and the resulting estimators are shown to be consistent and asymptotically normal with easily estimated variances. The simulation studies show that our estimation procedure is reliable and useful. 展开更多
关键词 Additive hazards model time-varying coefficients weighted local pseudoscore function asymptotic property
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ON NONLINEAR ELLIPTIC HEMIVARIATIONAL INEQUALITIES OF SECOND ORDER
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作者 Leszek Gasinski Nikolaos S.Papageorgiou 《Acta Mathematica Scientia》 SCIE CSCD 2004年第3期451-462,共12页
In this paper, a nonlinear hemivariational inequality of second order with a forcing term of subcritical growth is studied. Using techniques from multivalued analysis and the theory of nonlinear operators of monotone ... In this paper, a nonlinear hemivariational inequality of second order with a forcing term of subcritical growth is studied. Using techniques from multivalued analysis and the theory of nonlinear operators of monotone type, an existence theorem for the Dirichlet boundary value problem is proved. 展开更多
关键词 Locally Lipschitz function Clarke subdifferential measurable selection pseudomonotone operator GENERALIZED coercive operator Rayleigh quotient surject operator
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Transport Properties of Si and Ge Liquid Semiconductor Metals
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作者 Aditya M.Vora 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第3期550-554,共5页
In the present article, we study the electrical resistivity ρ, the thermoelectric power (TEP) α, thermal conductivity σ, Knight-Shifts and temperature coefficient of the Knight-Shifts of the liquid Si and Ge usin... In the present article, we study the electrical resistivity ρ, the thermoelectric power (TEP) α, thermal conductivity σ, Knight-Shifts and temperature coefficient of the Knight-Shifts of the liquid Si and Ge using the well known model potential for the first time. The structure factor used in the present work is derived from the Percus-Yevick (PY) theory. Various local field correction functions are used to study the screening influence. The present results of resistivity are found in qualitative agreement with available experimental and theoretical whenever exists. 展开更多
关键词 PSEUDOPOTENTIAL electrical resistivity thermoelectric power Knight Shift PY theory local field correction functions
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Electron Dispersion in Liquid Alkali and Their Alloys
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作者 Aditya M.Vora 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第7期159-166,共8页
Ashcroft's local empty core (EMC) model pseudopotential in the second-order perturbation theory is used to study the electron dispersion relation, the Fermi energy, and deviation in the Fermi energy from free elect... Ashcroft's local empty core (EMC) model pseudopotential in the second-order perturbation theory is used to study the electron dispersion relation, the Fermi energy, and deviation in the Fermi energy from free electron value for the liquid alkali metals and their equiatomic binary alloys for the first time. In the present computation, the use of pseudo-alloy-atom model (PAA) is proposed and found successful. The influence of the six different forms of the local field correction functions proposed by Hartree (H), Vashishta Singwi (VS), Taylor (T), lehimaru-Utsumi (IU), Farid et al. (F), and Sarkar et al. (S) on the aforesaid electronic properties is examined explicitly, which reflects the varying effects of screening. The depth of the negative hump in the electron dispersion of liquid alkalis decreases in the order Li --→ K, except for Rb and Cs, it increases. The results of alloys are in predictive nature. 展开更多
关键词 PSEUDOPOTENTIAL Fermi energy electron dispersion curves local field correction functions alkalimetals and their alloys
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Distributed Optimization for Heterogenous Second⁃Order Multi⁃Agent Systems
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作者 Qing Zhang Zhikun Gong +1 位作者 Zhengquan Yang Zengqiang Chen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2020年第4期53-59,共7页
A continuous⁃time distributed optimization was researched for second⁃order heterogeneous multi⁃agent systems.The aim of this study is to keep the velocities of all agents the same and make the velocities converge to t... A continuous⁃time distributed optimization was researched for second⁃order heterogeneous multi⁃agent systems.The aim of this study is to keep the velocities of all agents the same and make the velocities converge to the optimal value to minimize the sum of local cost functions.First,an effective distributed controller which only uses local information was designed.Then,the stability and optimization of the systems were verified.Finally,a simulation case was used to illustrate the analytical results. 展开更多
关键词 distributed optimization heterogeneous multi⁃agent system local cost function CONSENSUS
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Spatially Resolved Analytical Electron Microscopy at Grain Boundaries of α-Al_2O_3
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作者 S.Nufer, A.G.Marinopoulos, C.Elsasser, W.Kurtz and M.RuhleMax-Planck-Institut fur Metallforschung, Seestr. 92, D-70174 Stuttgart, Germany 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2002年第2期189-190,共2页
In this work the electronic structure and the impurity excess of the basal and rhombohedral twin grain boundaries are investigated, using electron energy loss spectroscopy (EELS) and energy dispersive X-ray spectrosco... In this work the electronic structure and the impurity excess of the basal and rhombohedral twin grain boundaries are investigated, using electron energy loss spectroscopy (EELS) and energy dispersive X-ray spectroscopy (EDXS). The measurability of electronic structures of the twin grain boundaries are discussed by comparing theoretical density of states (DOS) from bulk material with interfacial DOS, obtained from local density functional theory (LDFT) calculations. 展开更多
关键词 Grain boundaries Alumina (α-Al2O3) Local density function theory (LDFT) Electron energy loss spectroscopy (EELS)
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MULTIPLIERS ON WEIGHTED FUNCTION SPACES OVER LOCALLY COMPACT VILENKIN GROUPS
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作者 Zhu Yueping (Nantong Teachers College, China) 《Approximation Theory and Its Applications》 2002年第2期65-71,共7页
In this note, we consider the multipliers on weighted function spaces over totally disconnected locally compact abelian groups (Vilenkin groups). Firstly we show an (H1 ,L ) multiplier result. We also give an (Hap ,Ha... In this note, we consider the multipliers on weighted function spaces over totally disconnected locally compact abelian groups (Vilenkin groups). Firstly we show an (H1 ,L ) multiplier result. We also give an (Hap ,Hap) multiplier result under a similiar condition of Lu Yang type. In section 2, we obtain a result about the boundedness of multipliers on weighted Besov spaces. 展开更多
关键词 MATH MULTIPLIERS ON WEIGHTED FUNCTION SPACES OVER LOCALLY COMPACT VILENKIN GROUPS
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Study of Thermodynamics of Liquid Noble-Metals Alloys Through a Pseudopotential Theory
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作者 Aditya M.Vora 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第9期551-558,共8页
The Gibbs-Bogoliubov (GB) inequality is applied to investigate the thermodynamic properties of some equiatomic noble metal alloys in liquid phase such as Au-Cu, Ag-Cu, and Ag-Au using well recognized pseudopotential... The Gibbs-Bogoliubov (GB) inequality is applied to investigate the thermodynamic properties of some equiatomic noble metal alloys in liquid phase such as Au-Cu, Ag-Cu, and Ag-Au using well recognized pseudopotential formalism. For description of the structure, well known Percus-Yevick (PY) hard sphere model is used as a reference system. By applying a variation method the best hard core diameters have been found which correspond to minimum free energy. With this procedure the thermodynamic properties such as entropy and heat of mixing have been computed. The influence of local field correction function viz; Hartree (H), Taylor (T), lehimaru-Utsumi (IU), Farid et al. (F), and Sarkar et al. (S) is also investigated. The computed results of the excess entropy compares favourably in the case of liquid alloys while the agreement with experiment is poor in the case of heats of mixing. This may be due to the sensitivity of the heats of mixing with the potential parameters and the dielectric function. 展开更多
关键词 Gibbs-Bogoliubov (GB) inequality liquid noble metals binary alloys pseudopotential method Percus-Yevick (PY) hard sphere model local field correction functions thermodynamic properties
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