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Finite Words,Infinite Wisdom
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作者 DENG DI 《China Today》 2024年第5期70-72,共3页
As picture books gain popularity,they create a bridge between China and the rest of the world.
关键词 FINITE infinitE BRIDGE
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Infinitely Many Solutions and a Ground-State Solution for Klein-Gordon Equation Coupled with Born-Infeld Theory
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作者 Fangfang Huang Qiongfen Zhang 《Journal of Applied Mathematics and Physics》 2024年第4期1441-1458,共18页
In this paper, we intend to consider a kind of nonlinear Klein-Gordon equation coupled with Born-Infeld theory. By using critical point theory and the method of Nehari manifold, we obtain two existing results of infin... In this paper, we intend to consider a kind of nonlinear Klein-Gordon equation coupled with Born-Infeld theory. By using critical point theory and the method of Nehari manifold, we obtain two existing results of infinitely many high-energy radial solutions and a ground-state solution for this kind of system, which improve and generalize some related results in the literature. 展开更多
关键词 Klein-Gordon Equation Born-Infeld Theory infinitely Many Solutions Ground-State Solution Critical Point Theory
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英语V+To+Infinitive与V+To+V-ing结构的对比分析
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作者 周芬 《韶关学院学报》 2012年第7期58-62,共5页
英语v+to+infinitive与v+to+v-ing结构极易发生混淆。在句法上,v+to+infinitive结构中的to+infinitive要么是CP,要么是TP,而v+to+v-ing结构中的to+v-ing是介词短语PP。从语义角度来说,我们可以用主动词提示的时间做参照,to+infinitive... 英语v+to+infinitive与v+to+v-ing结构极易发生混淆。在句法上,v+to+infinitive结构中的to+infinitive要么是CP,要么是TP,而v+to+v-ing结构中的to+v-ing是介词短语PP。从语义角度来说,我们可以用主动词提示的时间做参照,to+infinitive所蕴含事件的时间要么发生在主动词时间之后或是与之同时发生,而to v-ing所蕴含的事件可以发生在主动词时间之前,之后或同时发生。另外,与to+infinitive结构不同的是v-ing结构更加倾向强调所发生事件的内部组成成分,所持续的时间和展开的方式等。 展开更多
关键词 v+to+infinitive结构 v+to+v-ing结构 句法 语义
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“V+to infinitive”与“V+Ving”的认知阐释
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作者 陈蕾 朱军平 《江西教育学院学报》 2006年第4期68-70,共3页
从认知学的角度对“V+toinfinitive”和“V+Ving”现象进行阐释,认为“V+toinfinitive”与“V+Ving”有其自身的框架与ICM,可视为一种构式。
关键词 V+to infiinitive V+Ving 认知 框架 构式
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Analysis of ground vibrations due to underground trains by 2.5D finite/infinite element approach 被引量:18
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作者 Hsiao-Hui Hung Y. B. Yang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第3期327-335,共9页
The 2.5D finite/infinite element approach is adopted to study wave propagation problems caused by underground moving trains. The irregularities of the near field, including the tunnel structure and parts of the soil, ... The 2.5D finite/infinite element approach is adopted to study wave propagation problems caused by underground moving trains. The irregularities of the near field, including the tunnel structure and parts of the soil, are modeled by the finite elements, and the wave propagation properties of the far field extending to infinity are modeled by the infinite elements. One particular feature of the 2.5D approach is that it enables the computation of the three-dimensional response of the half-space, taking into account the load-moving effect, using only a two-dimensional profile. Although the 2.5D finite/infinite element approach shows a great advantage in studying the wave propagation caused by moving trains, attention should be given to the calculation aspects, such as the rules for mesh establishment, in order to avoid producing inaccurate or erroneous results. In this paper, some essential points for consideration in analysis are highlighted, along with techniques to enhance the speed of the calculations. All these observations should prove useful in making the 2.5D finite/infinite element approach an effective one. 展开更多
关键词 ground vibrations 2.5D finite/infinite element underground train wave number wave propagation
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Computing of the Anchor by the Method of Three-Dimension Point-Radiate Infinite Elements 被引量:8
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作者 王艳芬 王元汉 谢洪阳 《Journal of China University of Geosciences》 SCIE CSCD 2007年第2期185-190,共6页
On the basis of the one-dimension infinite element theory, the coordinate translation and shape function of 3D point-radiate 8-node and 4-node infinite elements are derived. They are coupled with 20-node and 8-node fi... On the basis of the one-dimension infinite element theory, the coordinate translation and shape function of 3D point-radiate 8-node and 4-node infinite elements are derived. They are coupled with 20-node and 8-node finite elements to compute the compression distortion of the prestressed anchorage segment. The results indicate that when the prestressed force acts on the anchorage head and segment, the stresses and the displacements in the rock around the anchorage head and segment concentrate on the zone center with the anchor axis, and they decrease with exponential forms. Therefore,the stresses and the displacement spindles are formed. The calculating results of the infinite element are close to the theoretical results. This indicates the method is right. This article introduces a new way to study the mechanism of prestressed anchors. The obtained results have an important role in the research of the anchor mechanism and engineering application. 展开更多
关键词 infinite element prestressed anchor COUPLE finite element
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基于Infinite integral的四象限探测器光斑位置检测算法 被引量:7
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作者 苟晔鹏 刘星 +2 位作者 刘强 郭甲崇 邢博 《激光与红外》 CAS CSCD 北大核心 2021年第9期1249-1256,共8页
为了进一步提高基于四象限探测器的半主动式激光导引头的目标定位精度,本文以高斯分布的圆形光斑作为入射光斑模型,提出了一种基于Infinite integral拟合方法的改进算法(GII)。在Infinite integral拟合算法的基础上,考虑了外部光能和死... 为了进一步提高基于四象限探测器的半主动式激光导引头的目标定位精度,本文以高斯分布的圆形光斑作为入射光斑模型,提出了一种基于Infinite integral拟合方法的改进算法(GII)。在Infinite integral拟合算法的基础上,考虑了外部光能和死区带来的误差影响,采用最小二乘法获得最佳拟合的解析表达式。为了简化算法的计算量,对部分解析表达式进行分段式多项式拟合,优化拟合区间,并得到GII算法的解析表达式。GII算法相较于传统Infinite integral拟合算法和8次多项式拟合法,精度大幅度提升。仿真和实验表明,该算法在确保良好实时性的同时,能增加四象限探测器的有效探测范围,提高不同光斑半径下四象限探测器的定位精度,为战场环境下精准激光制导武器的发展提供了理论参考。 展开更多
关键词 光斑位置检测 四象限探测器 infinite integral算法 分段多项式拟合
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Interaction between infinitely many dislocations and a semi-infinite crack in one-dimensional hexagonal quasicrystal 被引量:10
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作者 刘官厅 杨丽英 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期280-284,共5页
By means of analytic function theory, the problems of interaction between infinitely many parallel dislocations and a semi-infinite crack in one-dimensional hexagonal quasicrystal are studied. The analytic solutions o... By means of analytic function theory, the problems of interaction between infinitely many parallel dislocations and a semi-infinite crack in one-dimensional hexagonal quasicrystal are studied. The analytic solutions of stress fields of the interaction between infinitely many parallel dislocations and a semi-infinite crack in one-dimensional hexagonal quasicrystal are obtained. They indicate that the stress concentration occurs at the dislocation source and the tip of the crack, and the value of the stress increases with the number of the dislocations increasing. These results are the development of interaction among the finitely many defects of quasicrystals, which possesses an important reference value for studying the interaction problems of infinitely many defects in fracture mechanics of quasicrystal. 展开更多
关键词 quasicrystals infinitely many dislocations semi-infinite crack interaction
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Completeness of Eigenfunction Systems for Off-Diagonal Infinite-Dimensional Hamiltonian Operators 被引量:15
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作者 侯国林 阿拉坦仓 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第2期237-241,共5页
For the off-diagonal infinite dimensional Hamiltonian operators, which have at most countable eigenvalues, a necessary and sufficient condition of the eigenfunction systems to be complete in the sense of Cauchy princi... For the off-diagonal infinite dimensional Hamiltonian operators, which have at most countable eigenvalues, a necessary and sufficient condition of the eigenfunction systems to be complete in the sense of Cauchy principal value is presented by using the spectral symmetry and new orthogonal relationship of the operators. Moreover, the above result is extended to a more general case. At last, the completeness of eigenfunction systems for the operators arising from the isotropic plane magnetoelectroelastic solids is described to illustrate the effectiveness of the criterion. The whole results offer theoretical guarantee for separation of variables in Hamiltonian system for some mechanics equations. 展开更多
关键词 Hamiltonian system infinite dimensional Hamiltonian operator COMPLETENESS Cauchy principalvalue magnetoelectroelastic solid
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Mixed-solvothermal Synthesis, Crystal Structure and Luminescence of a New Dinuclear Yttrium(Ⅲ) Coordination Polymer with 1-D Wave-like Infinite Chains 被引量:5
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作者 冯玉全 姜兰婷 +1 位作者 邢正正 王璐 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第5期825-831,共7页
A new dinuclear Y(3+) coordination polymer{[Y2(H2O)2(C(14)H8O4)3(C(12)H8N2)2]·3 H2O}n (1, C(14)H8 O4 = 2,2'-biphenyldicarboxylate, phen = 1,10-phenanthroline), has been obtained by means of a mi... A new dinuclear Y(3+) coordination polymer{[Y2(H2O)2(C(14)H8O4)3(C(12)H8N2)2]·3 H2O}n (1, C(14)H8 O4 = 2,2'-biphenyldicarboxylate, phen = 1,10-phenanthroline), has been obtained by means of a mixed-solvothermal method using ethylene glycol and water as solvent. The compound was characterized by elemental analysis, energy-dispersive X-ray spectroscopy(EDS), IR spectrum and single-crystal X-ray diffraction. The results reveal that 1 belongs to monoclinic system, space group C2/c with a = 24.249(3), b = 12.069(48), c = 22.7304(08) A, β = 113.480(7)°, Z = 4, V = 6102(2) A3, Dc = 1.462 g·cm^-3, F(000) = 2728, μ = 1.968 mm(-1), the final R = 0.0673, w R = 0.1508 and S = 1.085. Its structure can be regarded as a 1-D coordination polymer constructed by Y^3+ cations, 2,2A-biphenyldicarboxylate, 1,10-phenanthroline and water molecules. The compound not only contains two kinds of organic ligands, but also exhibits interesting wave-like infinite chains and 18-MR windows with the diameter of 4.070(7)A × 5.326(9)A. The structure is further stabilized by means of O–H…O hydrogen bonds and π-π stacking interactions. Furthermore, the luminescent properties(including emission spectrum, CIE chromaticity coordinate and decay curve) of 1 were also investigated in the solid-state at room temperature. 展开更多
关键词 mixed-solvothermal synthesis dinuclear Y^3+ coordination polymer wave-like infinite chains luminescent properties
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INFINITELY MANY SOLUTIONS FOR AN ELLIPTIC PROBLEM INVOLVING CRITICAL NONLINEARITY 被引量:2
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作者 曹道民 严树森 《Acta Mathematica Scientia》 SCIE CSCD 2010年第6期2017-2032,共16页
We study the following elliptic problem:{-div(a(x)Du)=Q(x)|u|2-2u+λu x∈Ω,u=0 onδΩ Under certain assumptions on a and Q, we obtain existence of infinitely many solutions by variational method.
关键词 semilinear elliptic equations infinitely many solutions variational method
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Constructing infinite sequence exact solutions of nonlinear evolution equations 被引量:3
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作者 套格图桑 那仁满都拉 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第11期23-33,共11页
To construct the infinite sequence new exact solutions of nonlinear evolution equations and study the first kind of elliptic function, new solutions and the corresponding B^cklund transformation of the equation are pr... To construct the infinite sequence new exact solutions of nonlinear evolution equations and study the first kind of elliptic function, new solutions and the corresponding B^cklund transformation of the equation are presented. Based on this, the generalized pentavalent KdV equation and the breaking soliton equation are chosen as applicable examples and infinite sequence smooth soliton solutions, infinite sequence peak solitary wave solutions and infinite sequence compact soliton solutions are obtained with the help of symbolic computation system Mathematica. The method is of significance to search for infinite sequence new exact solutions to other nonlinear evolution equations. 展开更多
关键词 first kind of elliptic function Backlund transformation nonlinear evolution equation new infinite sequence exact solutions
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EXACT ANALYSIS OF WAVE PROPAGATION IN AN INFINITE RECTANGULAR BEAM 被引量:2
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作者 孙卫明 杨光松 李东旭 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第7期768-778,共11页
The Fourier series method was extended for the exact analysis of wave propagation in an infinite rectangular beam.Initially,by solving the three-dimensional elastodynamic equations a general analytic solution was deri... The Fourier series method was extended for the exact analysis of wave propagation in an infinite rectangular beam.Initially,by solving the three-dimensional elastodynamic equations a general analytic solution was derived for wave motion within the beam.And then for the beam with stress-free boundaries,the propagation characteristics of elastic waves were presented.This accurate wave propagation model lays a solid foundation of simultaneous control of coupled waves in the beam. 展开更多
关键词 infinite rectangular beam wave propagation exact analysis Fourier series traveling wave active control
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BACKLUND TRANSFORMATION, NONLINEAR SUPERPOSITION FORMULAE AND INFINITE CONSERVED LAWS OF BENJAMIN EQUATION 被引量:1
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作者 ZHANG Hong-qing(张鸿庆) +1 位作者 ZHANG Yu-feng(张玉峰) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第10期1127-1131,共5页
Backlund transformation, exact solitary wave solutions, nonlinear supperposi tion formulae and infinite conserved laws are presented by using TU-pattern. The algorithm involves wide applications for nonlinear evolutio... Backlund transformation, exact solitary wave solutions, nonlinear supperposi tion formulae and infinite conserved laws are presented by using TU-pattern. The algorithm involves wide applications for nonlinear evolution equations. 展开更多
关键词 BENJAMIN equation BACKLUND transformation infinitE CONSERVED LAW
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Infinitely many periodic solutions for second-order Hamiltonian systems
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作者 尹翠翠 张福保 黄成山 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期549-551,共3页
The existence of high energy periodic solutions for the second-order Hamiltonian system -ü(t)+A(t)u(t)=▽F(t,u(t)) with convex and concave nonlinearities is studied, where F(t, u) = F1(t,u)+F2(t,... The existence of high energy periodic solutions for the second-order Hamiltonian system -ü(t)+A(t)u(t)=▽F(t,u(t)) with convex and concave nonlinearities is studied, where F(t, u) = F1(t,u)+F2(t,u). Under the condition that F is an even functional, infinitely many solutions for it are obtained by the variant fountain theorem. The result is a complement for some known ones in the critical point theory. 展开更多
关键词 variant fountain theorem second-order Hamiltonian system infinitely periodic solutions even functional
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DOUBLE WAVE DESCRIPTION OF SINGLE PARTICLE IN AN INFINITELY DEEP SQUARE POTENTIAL WELL 被引量:3
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作者 HUANG Xiangyou QIAN Shangwu +1 位作者 LIU Quanhui HE Zuoxiu 《Chinese Physics Letters》 SCIE CAS CSCD 1990年第4期152-155,共4页
Recently we have suggested that the state of a single particle should be jointly defined by two wave functions.In this letter we use this suggestion to discuss the motion of a single particle in an infinitely deep squ... Recently we have suggested that the state of a single particle should be jointly defined by two wave functions.In this letter we use this suggestion to discuss the motion of a single particle in an infinitely deep square potential well;the results obiained in the classical limit correctly describe the motion of the single particle with clarity. 展开更多
关键词 FUNCTIONS infinitELY PARTICLE
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Riemann Boundary Value Problem of Non-Normal Type on the Infinite Straight Line 被引量:2
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作者 Lixia Cao 《Applied Mathematics》 2013年第8期1226-1230,共5页
Various kinds of Riemann boundary value problems (BVPs) for analytic functions on closed curves or on open arc, doubly periodic Riemann BVPs, doubly quasi-periodic Riemann BVPs, and BVPs for polyanalytic functions hav... Various kinds of Riemann boundary value problems (BVPs) for analytic functions on closed curves or on open arc, doubly periodic Riemann BVPs, doubly quasi-periodic Riemann BVPs, and BVPs for polyanalytic functions have been widely investigated in [1-8]. The main ap- proach is to use the decomposition of polyanalytic functions and their generalization to transform the boundary value problems to their corresponding boundary value problems for analytic functions. Recently, inverse Riemann BVPs for generalized analytic functions or bianalytic functions have been investigated in [9-12]. In this paper, we consider a kind of Riemann BVP of non-normal type on the infinite straight line and discuss the solvable conditions and the general solution for it. 展开更多
关键词 Non-Normal Type RIEMANN BOUNDARY VALUE Problem The infinitE STRAIGHT Line
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Prediction of Infinite Dilution Activity Coefficients of Alcohol and Ether Organic Compounds in Water 被引量:2
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作者 王维 许惠英 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第12期1808-1813,共6页
Based on QSPR of alcohol and ether organic compounds in water,geometrical optimization and electrostatic potential calculations were performed at the HF/6-31G* level for 73 alcohol and ether organic compounds.Linear ... Based on QSPR of alcohol and ether organic compounds in water,geometrical optimization and electrostatic potential calculations were performed at the HF/6-31G* level for 73 alcohol and ether organic compounds.Linear relationships between infinite dilution activity coef-ficient(lnγ∞) of alcohols and ethers in water and theoretical descriptors of the molecular structure were established by multiple regression method.The result shows that the parameters derived from molecular electrostatic potential together with molecular surface area can be preferably used to express the quantitative structure-lnγ∞ relationship of alcohols and ethers in water.This reveals that this model has good predictive capabilities(RCV=0.969).The molecular electrostatic potential has also been proved to have the general applicability in QSPR model of alcohol and ether organic compounds about γ∞ in water.The QSPR model established may provide a new powerful method for predicting γ∞ of organic compounds in aqueous systems. 展开更多
关键词 alcohol and ether organic compounds infinite dilution activity coefficient(γ∞) molecular electrostatic potential QSPR
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Preparation of Superconducting Thin Films of Infinite-Layer Nickelate Nd_(0.8)Sr_(0.2)NiO_(2) 被引量:3
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作者 Qiang Gao Yuchen Zhao +1 位作者 Xing-Jiang Zhou Zhihai Zhu 《Chinese Physics Letters》 SCIE CAS CSCD 2021年第7期136-139,共4页
The recent observation of superconductivity in thin films of infinite-layer nickelate Nd_(0.8)Sr_(0.2)NiO_(2) has received considerable attention.Despite the many efforts to understand the superconductivity in infinit... The recent observation of superconductivity in thin films of infinite-layer nickelate Nd_(0.8)Sr_(0.2)NiO_(2) has received considerable attention.Despite the many efforts to understand the superconductivity in infinite-layer nickelates,a consensus on the underlying mechanism for the superconductivity has yet to be reached,partly owing to the challenges with the material synthesis.Here,we report the successful growth of superconducting infinite-layer Nd_(0.8)Sr_(0.2)NiO_(2) films by pulsed laser deposition and soft chemical reduction.The details on the growth process are discussed. 展开更多
关键词 synthesis REDUCTION infinitE
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Prediction of Infinite Dilution Activity Coefficients of Halogenated Hydrocarbons in Water 被引量:2
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作者 许惠英 闵剑青 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第4期491-497,共7页
Geometrical optimization and electrostatic potential calculations have been performed for a series of halogenated hydrocarbons at the HF/Gen-6d level. A number of electrostatic potentials and the statistically based s... Geometrical optimization and electrostatic potential calculations have been performed for a series of halogenated hydrocarbons at the HF/Gen-6d level. A number of electrostatic potentials and the statistically based structural descriptors derived from these electrostatic potentials have been obtained. Multiple linear regression analysis and artificial neural network are employed simultaneously in this paper. The result shows that the parameters derived from electrostatic 2 potentials σtot^2, V s and ∑ Vs^+, together with the molecular volume (Vine) can be used to express the quantitative structure-infinite dilution activity coefficients (γ^∞) relationship of halogenated hydrocarbons in water. The result also demonstrates that the model obtained by using BFGS quasiNewton neural network method has much better predictive capability than that from multiple linear regression. The goodness of the model has been validated through exploring the predictive power for the external test set. The model obtained via neural network may be applied to predict γ^∞ of other halogenated hydrocarbons not present in the data set. 展开更多
关键词 halogenated hydrocarbons molecular electrostatic potentials infinite dilution activity coefficients (γ^∞) QSPR artificial neural networks
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