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Strong Convergence and Its Rate of Modified Partitioning Estimation for Nonparametric Regression Function under Dependence Samples 被引量:5
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作者 凌能祥 《Northeastern Mathematical Journal》 CSCD 2004年第3期349-354,共6页
In this paper, we study the strong consistency and convergence rate for modified partitioning estimation of regression function under samples that are ψ-mixing with identically distribution.
关键词 partitioning esfimation strong convergence convergence rate nonpara-metric regression function Ψ-MIXING
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Strong Convergence of Partitioning Estimation for Nonparametric Regression Function under Dependence Samples 被引量:4
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作者 LING Neng-xiang DU Xue-qiao 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第1期28-33,共6页
In this paper, we study the strong consistency for partitioning estimation of regression function under samples that axe φ-mixing sequences with identically distribution.Key words: nonparametric regression function; ... In this paper, we study the strong consistency for partitioning estimation of regression function under samples that axe φ-mixing sequences with identically distribution.Key words: nonparametric regression function; partitioning estimation; strong convergence;φ-mixing sequences. 展开更多
关键词 nonparametric regression function partitioning estimation strong convergence φ-mixing sequences
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Alloy gene Gibbs energy partition function and equilibrium holographic network phase diagrams of AuCu_3-type sublattice system 被引量:3
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作者 谢佑卿 李小波 +2 位作者 刘心笔 聂耀庄 彭红建 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3585-3610,共26页
Taking AuCu3-type sublattice system as an example, three discoveries have been presented: First, the third barrier hindering the progress in metal materials science is that researchers have got used to recognizing exp... Taking AuCu3-type sublattice system as an example, three discoveries have been presented: First, the third barrier hindering the progress in metal materials science is that researchers have got used to recognizing experimental phenomena of alloy phase transitions during extremely slow variation in temperature by equilibrium thinking mode and then taking erroneous knowledge of experimental phenomena as selected information for establishing Gibbs energy function and so-called equilibrium phase diagram. Second, the equilibrium holographic network phase diagrams of AuCu3-type sublattice system may be used to describe systematic correlativity of the composition?temperature-dependent alloy gene arranging structures and complete thermodynamic properties, and to be a standard for studying experimental subequilibrium order-disorder transition. Third, the equilibrium transition of each alloy is a homogeneous single-phase rather than a heterogeneous two-phase, and there exists a single-phase boundary curve without two-phase region of the ordered and disordered phases; the composition and temperature of the top point on the phase-boundary curve are far away from the ones of the critical point of the AuCu3 compound. 展开更多
关键词 AuCu3 compound AuCu3-type sublattice system alloy gene Gibbs energy partition function equilibrium holographic network phase diagram systematic metal materials science
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Alloy gene Gibbs energy partition function and equilibrium holographic network phase diagrams of Au_3Cu-type sublattice system 被引量:3
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作者 谢佑卿 聂耀庄 +2 位作者 李小波 彭红建 刘心笔 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第1期211-240,共30页
Taking Au3Cu-type sublattice system as an example, three discoveries have been presented. First, the fourth barrier to hinder the progress of metal materials science is that today’s researchers do not understand that... Taking Au3Cu-type sublattice system as an example, three discoveries have been presented. First, the fourth barrier to hinder the progress of metal materials science is that today’s researchers do not understand that the Gibbs energy function of an alloy phase should be derived from Gibbs energy partition function constructed of alloy gene sequence and their Gibbs energy sequence. Second, the six rules for establishing alloy gene Gibbs energy partition function have been discovered, and it has been specially proved that the probabilities of structure units occupied at the Gibbs energy levels in the degeneracy factor for calculating configuration entropy should be degenerated as ones of component atoms occupied at the lattice points. Third, the main characteristics unexpected by today’s researchers are as follows. There exists a single-phase boundary curve without two-phase region coexisting by the ordered and disordered phases. The composition and temperature of the top point on the phase-boundary curve are far away from those of the critical point of the Au3Cu compound; At 0 K, the composition of the lowest point on the composition-dependent Gibbs energy curve is notably deviated from that of the Au3Cu compounds. The theoretical limit composition range of long range ordered Au3Cu-type alloys is determined by the first jumping order degree. 展开更多
关键词 Au3Cu compound Au3Cu-type sublattice system alloy gene Gibbs energy partition function equilibrium holographic network phase diagrams systematic metal materials science
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在随机损失数据情况下回归函数的Partitioning估计的强相合性
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作者 沙秋英 《黑龙江大学自然科学学报》 CAS 1996年第1期10-15,共6页
本文在不完全数据的情况下采用L1模得到了回归函数的Partitioning估计的强相合性.我们的结果只要求回归函数的P(P>1)阶矩有限,对回归函数没加任何光滑条件,并且我们的结果对任何分布都成立.
关键词 强相合 回归函数 随机损失数据 P估计
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Fingerprint Directional Image Partitioning Based on Genetic Algorithm
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作者 张朝鸣 刘云超 《Advances in Manufacturing》 SCIE CAS 2000年第S1期98-103,共6页
In this work, we introduce a method of fingerprint directional image partitioning based on GA. According to the fingerprint topology, A set of dynamic partition masks and a cost estimating function are designed to gui... In this work, we introduce a method of fingerprint directional image partitioning based on GA. According to the fingerprint topology, A set of dynamic partition masks and a cost estimating function are designed to guide the partitioning procedure. Finding best fitted mask application is converted to an functional optimizing problem, and we give out a GA solution to the problem. At last, we discuss the application of the proposed method in Fingerprint Classification. 展开更多
关键词 fingerprint classification directional image partitioning dynamic mask cost estimating function genetic algorithm (GA)
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Alloy Gene Gibbs Energy Partition Function and Equilibrium Holographic Network Phase Diagrams of AuCu-Type Sublattice System 被引量:4
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作者 Youqing Xie Xiaobo Li +2 位作者 Xinbi Liu Yaozhuang Nie Hongjian Peng 《International Journal of Communications, Network and System Sciences》 2013年第10期415-442,共28页
Taking AuCu-sublattice system as an example, we present two discoveries and a method. First, the alloy gene sequences are the central characteristic atom sequences in the basic coordination cluster sequences. Second, ... Taking AuCu-sublattice system as an example, we present two discoveries and a method. First, the alloy gene sequences are the central characteristic atom sequences in the basic coordination cluster sequences. Second, the transmission mode of the information about structures and properties of the alloy genes is described by the alloy gene Gibbs energy partition function. The most valuable method in the system sciences is “the whole obtained from a few parts”. We have established the alloy gene database and holographic alloy positioning system of the Au-Cu system, as well as alloy gene Gibbs energy partition function and equilibrium holographic network phase diagrams of the AuCu-type sublattice system. It means that a standard way for researchers to share predictive algorithms and computational methods may be produced during designing advanced alloys. 展开更多
关键词 ALLOY GENE Gibbs Energy partitION function HOLOGRAPHIC ALLOY POSITIONING System EQUILIBRIUM
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Studies of n-Octanol/water Partition Coefficients (lgK_(ow)) for Organophosphate Compounds by Density Functional Theory 被引量:2
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作者 LIU Hong-Xia WANG Zun-Yao +2 位作者 ZHAI Zhi-Cai LIU Hong-Yan WANG Lian-Sheng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第3期367-373,共7页
Optimized calculation of 35 dialkyl phenyl phosphate compounds (OPs) was carded out at the B3LYP/6-31G^* level in Gaussian 98 program. Based on the theoretical linear solvation energy relationship (TLSER) model, ... Optimized calculation of 35 dialkyl phenyl phosphate compounds (OPs) was carded out at the B3LYP/6-31G^* level in Gaussian 98 program. Based on the theoretical linear solvation energy relationship (TLSER) model, the obtained parameters were taken as theoretical descriptors to establish the novel QSPR model for predicting n-octanol/water partition coefficients (lgKow) of OPs. The new model achieved in this work contains three variables, i.e., molecular volume (Vm), dipole moment of the molecules (μ) and enthalpy (H^0). For this model, R^2 = 0.9167 and SD = 0.31 at large t values. In addition, the variation inflation factors (VIF) of variables are all close to 1.0, suggesting high accuracy of the predicting model. And the results of cross-validation test (q^2 = 0.8993) and method validation also showed the model of this study exhibited optimum stability and better predictive power than that from semi-empirical method. The model achieved can be used to predict IgKow of congeneric compounds. 展开更多
关键词 organophosphate compounds (OPs) n-octanol/water partition coefficients (Kow) quantitative structure-property relationship (QSPR) density functional theory (DFT)
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Partition Functions for Diatomic Molecules in Plasmas out of Thermal Equilibrium 被引量:1
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作者 Graldine FAURE 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第3期192-200,共9页
Two calculation methods on the partition functions for diatomic molecules in plas- mas out of thermal equilibrium are reported. A Boltzmann distribution for the electronic, vi- brational and rotational quantum levels ... Two calculation methods on the partition functions for diatomic molecules in plas- mas out of thermal equilibrium are reported. A Boltzmann distribution for the electronic, vi- brational and rotational quantum levels is assumed in the two calculation methods. The results obtained by two methods are displayed for four sorts of diatomic molecules, 02, N2, OH and NO, that are present in humid air plasmas. The calculation method of density for the electronically excited states is developed. Finally, a method to calculate the partition functions for simulating the non-normalized diatomic spectra is discussed. 展开更多
关键词 partition function Boltzmann distribution diatomic molecule
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Rapidly calculating the partition function of macroscopic systems
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作者 李菁田 宁博元 +2 位作者 龚乐诚 庄军 宁西京 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第3期236-241,共6页
It has remained an open problem to accurately compute the partition function of macroscopic systems since the establishment of statistical physics. A rapid method approaching this problem was presented and was strictl... It has remained an open problem to accurately compute the partition function of macroscopic systems since the establishment of statistical physics. A rapid method approaching this problem was presented and was strictly tested by molecular dynamic (MD) simulations on Ar atoms in both dense gaseous and liquid states. The outcomes from the method on the internal energy and the work of isothermal expansion (and therefore the free energy) are in good agreement with the MD simulations, suggesting the method would be immediately applied in vast areas. 展开更多
关键词 partition function statistical physics free energy calculation
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Pseudo-Classical Partition Function of Spin One-Half Derived by Coherent State Method
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作者 许业军 范洪义 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第6期1046-1048,共3页
Using the bosonic coherent state representation and the Schwinger bosonic operator realization of angular momentum we find the formula for the quantum Hamiltonian H =iaiUijUjl a1 for SU(2) rotation U, in this way w... Using the bosonic coherent state representation and the Schwinger bosonic operator realization of angular momentum we find the formula for the quantum Hamiltonian H =iaiUijUjl a1 for SU(2) rotation U, in this way we further specify the angular velocity w, iUU = (1/2)σ·ω, where σ is the Pauli matrix. Though the spin as a quantum observable has no classical correspondence, we may still mimic it as a rigid body rotation characterized by 3 Euler angles, and calculate its Pseudo-classical rotational partition function of spin one-half. 展开更多
关键词 partition function coherent state angular velocity the IWOP technique
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Reduced Partition Function Ratio in the Frequency Complex Plane: A Mathematical Approach
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作者 Jie Yuan 《Open Journal of Geology》 2014年第12期654-664,共11页
This paper gives a mathematical approach to calculate the fractionation factor of isotopes in a general cluster (also known as?super-molecule), which composes of necessary chemical effect within three bonds outside th... This paper gives a mathematical approach to calculate the fractionation factor of isotopes in a general cluster (also known as?super-molecule), which composes of necessary chemical effect within three bonds outside the interested atom(s). The cluster might have imaginary frequencies after being optimized in quantum softwares. The approach includes the contribution of the difference, which is resulted from the substitution of heavy and light isotopes in the cluster, of vibrations of imaginary frequencies to give precise prediction of isotope fractionation factor. We call the new mathematical approximation “reduced partition function ratio in the frequency complex plane (RPFRC)”. If there is no imaginary frequency for a cluster, RPFRC?is simplified to be Urey (1947) or Bigeleisen and Mayer (1947) formula. Final results of this new algorithm are in good agreement with those in earlier studies. 展开更多
关键词 ISOTOPE FRACTIONATION Cluster REDUCED partitION function RATIO FREQUENCY Complex Plane
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Estimation of n-Octanol/water Partition Coeffi-cients(lgK_(ow)) and the Aqueous Solubility(-lg_(Sw)) of all PCDF Congeners by Density Functional Theory
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作者 YANG Guo-Ying YU Jing +1 位作者 WANG Zun-Yao LIU Hong-Xia 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第9期1134-1140,共7页
Optimized calculation of dibenzofuran (DF) and 135 polychlorinated dibenzofurans (PCDFs) was carried out at the B3LYP/6-31G* level in GAUSSIAN 98 program. Based on the theoretical linear solvation energy relation... Optimized calculation of dibenzofuran (DF) and 135 polychlorinated dibenzofurans (PCDFs) was carried out at the B3LYP/6-31G* level in GAUSSIAN 98 program. Based on the theoretical linear solvation energy relationship (TLSER) model, the obtained structural parameters were taken as theoretical descriptors to establish the novel quantitative structureproperty relationship (QSPR) model for predicting n-octanol/water partition coefficients (lgKow) of PCDFs. The new model of lgKow achieved in this work contains three variables: energy of the highest occupied molecular orbital (EHOMO), the most negative atomic partial charge (q^-) and average molecular polarizability (a), of which R^2= 0.9011 and SD = 0,17 with larger t values. In addition, the variation inflation factors (VIF) of variables in the present model are all less than 5.5, suggesting high accuracy of the lgKow model. And the results of cross-validation test (q^2 = 0.8688) and method validation also show this model exhibits optimum stability and better predictive power than semi-empirical method. At the same time, it is found that the aqueous solubility (-lgSw) has high relative correlation with constant volume molar heat capacity (Cv^0), of which R^2 = 0.9777 and SD = 0.22. Moreover, lgKow and -lgSw values of all PCDF congeners were predicted respectively. 展开更多
关键词 polychlorinated dibenzofurans (PCDFs) n-octanol/water partition coefficients (lgKow) aqueous solubility (-lgSw) quantitative structureproperty relationship (QSPR) density functional theory (DFT)
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Calculation of Partition Function of QCD at Finite Chemical Potential
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作者 SUN Wei-Min ZONG Hong-Shi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第2期435-438,共4页
In equilibrium statistical field theory, the partition function has fundamental importance. In this paper we propose a direct and general method for calculating the partition function and equation of state of QCD at f... In equilibrium statistical field theory, the partition function has fundamental importance. In this paper we propose a direct and general method for calculating the partition function and equation of state of QCD at finite chemical potential. It is found that the partition function is totally determined by the dressed quark propagator at finite chemical potential up to a multiplicative constant. From this a criterion for the phase transition between the Nambu and the Wigner phases is obtained. This general method is applied to two specific cases: the free quark theory and QCD with a model dressed quark propagator having confinement features. In the first case, the standard Fermi distribution at T = 0 is reproduced. In the second case, we apply the conclusion in previous works to obtain the dressed quark propagator at finite chemical potential and find the unphysical result that the baryon number density vanishes for all values of chemical potential. The reason for this result is discussed. 展开更多
关键词 partition function of QCD phase transition
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Functional Equilibrium Between Photosynthetic and Above-ground Nonphotosynthetic Structures of Plants: Evidence from a Pruning Experiment with Three Subtropical Tree Species 被引量:4
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作者 曾波 《Acta Botanica Sinica》 CSCD 2003年第2期152-157,共6页
It is well known that plants have functional equilibrium between their above-ground parts (shoots) and below-ground parts (roots), but whether the above-ground parts of plants have functional equilibrium between their... It is well known that plants have functional equilibrium between their above-ground parts (shoots) and below-ground parts (roots), but whether the above-ground parts of plants have functional equilibrium between their photosynthetic structures (leaves) and non-photosynthetic structures (branches and stem) is unknown. The purpose of this study is to test the hypotheses that: (1) the above-ground parts of plants have functional equilibriums between their photosynthetic structures and non-photosynthetic structures; (2) the maintenance of the equilibriums is guaranteed by the alteration of biomass partitioning to photosynthetic and non-photosynthetic structures. To test these hypotheses, a pruning experiment with four pruning intensities (0%, 20%, 50%, and 70%) were carried out with three subtropical Chinese tree species ( Ficus microcarpa, Ficus virens, Cinnamomum camphora). Pruning treatments were conducted in two successive years. The results were in conformity with the hypothesis, i.e. above-ground parts of trees had functional equilibriums between photosynthetic and non-photosynthetic structures. Pruning decreased instantaneously the mass ratios of photosynthetic structures to non-photosynthetic structures (P/NP) of all three tree species, the reduction in P/NP was strengthened with pruning intensity. However, one year after pruning, the P/NP of all pruned trees increased and were not smaller than those of unpruned trees. In agreement with the expectation, the biomass partitioning of pruned trees was altered, more newly produced above-ground biomass was partitioned to leaf growth and less to branch and stem growth, thus enabled the damaged trees to restore their functional equilibrium between photosynthetic and non-photosynthetic structures. It is clear that the maintenance of functional equilibrium between photosynthetic and non-photosynthetic structures guaranteed by the alteration of biomass partitioning provides plants a good strategy to resist external disturbance and damage. 展开更多
关键词 biomass partitioning functional equilibrium non-photosynthetic structures photosynthetic structures tree
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PARTITION算法的实现
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作者 朱玉龙 任文岚 《小型微型计算机系统》 CSCD 北大核心 2003年第11期1954-1955,共2页
自 1 96 2年 Hoare提出快速排序算法以来 ,就成为各种程序设计、数据结构和算法等方面教科书的必备例题 .然而其中的 partition算法几乎都采取了二重循环的形式 ,掩盖了 partition的线性本质 ,削弱了程序的可读性 .本文介绍了 Nico Rom... 自 1 96 2年 Hoare提出快速排序算法以来 ,就成为各种程序设计、数据结构和算法等方面教科书的必备例题 .然而其中的 partition算法几乎都采取了二重循环的形式 ,掩盖了 partition的线性本质 ,削弱了程序的可读性 .本文介绍了 Nico Romuto所做的改进 ,最后给出了一种新的实现方法 ,采取了 while- if- else的形式 ,准确表达了 partition的线性本质 。 展开更多
关键词 快速排序 partition函数 while-if-else结构
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Partition算法及其实现
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作者 钟治初 《计算机与现代化》 2006年第2期44-45,共2页
划分算法是快速排序算法中的重要组成部分,本文讨论了划分算法的几种形式,将通常的双循环形式的算法改写成单循环形式的算法。
关键词 快速排序 算法 划分函数 循环结构
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海洋国土空间开发适宜性评价及其功能区划分——以莆田市海域为例
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作者 董卫卫 林桂兰 卢惠泉 《国土与自然资源研究》 2025年第2期28-35,共8页
海洋国土空间开发适宜性评价是海洋国土空间规划的重要基础研究和技术支撑专题。本文基于评价海域的自然资源条件、生态环境条件、区位地理条件和潜在灾害风险四个维度,构建海洋国土“两空间一红线”评价指标体系。采用文献参考法、特... 海洋国土空间开发适宜性评价是海洋国土空间规划的重要基础研究和技术支撑专题。本文基于评价海域的自然资源条件、生态环境条件、区位地理条件和潜在灾害风险四个维度,构建海洋国土“两空间一红线”评价指标体系。采用文献参考法、特征赋值法、德尔菲法、标准差限制法等确定指标分值及权重,利用“引导-限制”综合评价指标模型和Arc GIS空间分析工具,获得莆田市海域海洋国土空间开发适宜性评价。结果表明,莆田市适宜划为海洋生态空间的海域面积为2272 km^(2)(其中海洋生态保护红线面积1564 km^(2),海洋生态控制区面积708 km^(2)),占整个莆田市海域面积57.1%;渔业用海适宜区面积为3822km^(2),占整个海域面积96.8%;适宜建港岸线长136 km,占整个岸线长度24.7%;适宜开发滨海旅游岸线长148 km,占整个海岸线26.8%;风电场适宜开发面积2954 km^(2),占整个海域74.9%。通过与开发现状对比发现,现状为旅游、港口及养殖用海90%以上位于适宜区评价结果范围内,而位于不适宜区的用海经调研发现确实存在某些问题,验证了评价方法的准确性。最后基于适宜性评价结果,结合当地社会经济发展对海洋空间资源的配置需求,划分莆田市海洋空间功能区:海洋生态保护红线面积1564 km^(2),海洋生态控制区面积708 km^(2)、渔业用海面积972km^(2)、风电场用海面积627 km^(2)、游憩用海面积95 km^(2)、港口用海区面积164 km^(2)、海洋预留区面积77 km^(2)。海洋国土空间功能区的划分是国土空间规划的重要组成部分。 展开更多
关键词 海洋空间 开发适宜性 功能分区 莆田市
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maturity of associating liver partition and portal vein ligation for staged hepatectomy-derived liver regeneration in a rat model 被引量:5
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作者 Yi-fan Tong Ning Meng +6 位作者 Miao-qin Chen Han-ning Ying Ming Xu Billy Lu Jun-Jie Hong Yi-fan Wang Xiujun Cai 《World Journal of Gastroenterology》 SCIE CAS 2018年第10期1107-1119,共13页
AIM To establish a rat model for evaluating the maturity of liver regeneration derived from associating liver partition and portal vein ligation for staged hepatectomy(ALPPS).METHODS In the present study, ALPPS, parti... AIM To establish a rat model for evaluating the maturity of liver regeneration derived from associating liver partition and portal vein ligation for staged hepatectomy(ALPPS).METHODS In the present study, ALPPS, partial hepatecotmy(PHx), and sham rat models were established initially, which were validated by significant increase of proliferative markers including Ki-67, proliferating cell nuclear antigen, and cyclin D1. In the setting of accelerated proliferation in volume at the second and fifth day after ALPPS, the characteristics of newborn hepatocytes, as well as specific markers of progenitor hepatic cell, were identified. Afterwards, the detection of liver function followed by cluster analysis of functional gene expression were performed to evaluate the maturity.RESULTS Compared with PHx and sham groups, the proliferation of f LR was significantly higher in ALPPS group(P = 0.023 and 0.001 at second day, P = 0.034 and P < 0.001 at fifth day after stage I). Meanwhile, the increased expression of proliferative markers including Ki-67, proliferating cell nuclear antigen, and cyclin D1 verified the accelerated liver regeneration derived from ALPPS procedure. However, ALPPS-induced Sox9 positive hepatocytes significantly increased beyond the portal triad, which indicated the progenitor hepatic cell was potentially involved. And the characteristics of ALPPSinduced hepatocytes indicated the lower expression of hepatocyte nuclear factor 4 and anti-tryptase in early proliferative stage. Both suggested the immaturity of ALPPS-derived liver regeneration. Additionally, the detection of liver function and functional genes expression confirmed the immaturity of renascent hepatocytes derived in early stage of ALPPS-derived liver regeneration.CONCLUSION Our study revealed the immaturity of ALPPS-derived proliferation in early regenerative response, which indicated that the volumetric assessment overestimated the functional proliferation. This could be convincing evidence that the stage Ⅱ of ALPPS should be performed prudently in patients with marginally adequate f LR, as the ALPPS-derived proliferation in volume lags behind the functional regeneration. 展开更多
关键词 associating LIVER partitION and portal vein LIGATION for staged HEPATECTOMY LIVER regeneration Hepatic PROGENITOR cell function IMMATURE
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QSPR of n-Octanol/water Partition Coefficient (lgK_(ow)) for Alkyl(1-phenylsulfonyl) Cycloalkane-carboxylates 被引量:4
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作者 翟志才 柳红霞 +1 位作者 王遵尧 赵林飞 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第2期143-150,共8页
Quantum chemistry parameters of 28 alkyl(1-phenylsulfonyl) cycloalkane-carboxy-lates were computed at the 6-31G* level in fully optimal manner using B3LYP method of density functional theory (DFT). With GQSARF2.0... Quantum chemistry parameters of 28 alkyl(1-phenylsulfonyl) cycloalkane-carboxy-lates were computed at the 6-31G* level in fully optimal manner using B3LYP method of density functional theory (DFT). With GQSARF2.0 program, the correlation equations that can predict n-octanol/water partition coefficient (lgKow) were developed using the structural and thermodynamic parameters of 28 alkyl(1-phenylsulfonyl) cycloalkane-carboxylates with experimental data of lgKow as theoretical descriptors; the correlation coefficient (R^2) was 0.9452 and the cross-validation squared correlation coefficient (Rcv^2) 0.9312. Furthermore, a four-variable model from MEDV was obtained, of which R2 = 0.9497 and Rov^2 =0.9388. The models were validated by variance inflation factor (VIF) and t-test. Cross-validation indicates that the correlation and predicting ability of the model based on both DFT method and MEDV are more advantageous than those obtained from semi-empirical AM1 method. 展开更多
关键词 quantitative structure-property relationship (QSPR) alkyl(1-phenylsulfonyl) cycloalkane-carboxylate density functional theory (DFT) n-octanol/water partition coefficient (lgKow) molecular electronegativity distance vector (MEDV)
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