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陕西几种土壤过氧化氢酶的动力学和热力学特征 被引量:11
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作者 朱铭莪 白红英 代伟 《西北农林科技大学学报(自然科学版)》 CSCD 1989年第1期20-26,共7页
研究结果表明:供试六个土样的米氏常数,最大速度和最大速度/米氏常数,均有差异。各土壤过氧化氢酶的活化能也明显不同。活化焓差别较大,说明各土壤过氧化氢酶形成活化络合物时,底物与酶活性中心在应变和扭曲强度上的差异。活化嫡皆为负... 研究结果表明:供试六个土样的米氏常数,最大速度和最大速度/米氏常数,均有差异。各土壤过氧化氢酶的活化能也明显不同。活化焓差别较大,说明各土壤过氧化氢酶形成活化络合物时,底物与酶活性中心在应变和扭曲强度上的差异。活化嫡皆为负值,表明活化络合物形成时体系的有序性增加。活化自由能为正值,各土样差异较小。黄棕壤过氧化氢酶的各参数较为特殊。 展开更多
关键词 土壤 过氧化氢酶 活化能 自由能
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Dynamics of coherence-induced state ordering under Markovian channels 被引量:2
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作者 Long-Mei Yang Bin Chen +1 位作者 Shao-Ming Fei Zhi-Xi Wang 《Frontiers of physics》 SCIE CSCD 2018年第5期319-325,共7页
We study the dynamics of coherence-induced state ordering under incoherent channels, particularly four specific Markovian channels: amplitude damping channel, phase damping channel, depolarizing channel and bit flit ... We study the dynamics of coherence-induced state ordering under incoherent channels, particularly four specific Markovian channels: amplitude damping channel, phase damping channel, depolarizing channel and bit flit channel for single-qnbit states. We show that the amplitude damping channel, phase damping channel, and depolarizing channel do not change the coherence-induced state ordering by l1 norm of coherence, relative entropy of coherence, geometric measure of coherence, and Tsallis relative α-entropies, while the bit flit channel does change for some special cases. 展开更多
关键词 l1-norm of coherence relative entropy of coherence geometric measure of coherence Tsallis relative a-entropies of coherence ordering state
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Password Pattern and Vulnerability Analysis for Web and Mobile Applications 被引量:1
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作者 LI Shancang Imed Romdhani William Buchanan 《ZTE Communications》 2016年第B06期32-36,共5页
Text-based passwords are heavily used to defense for many web and mobile applications. In this paper, we investigated the patterns and vulnerabilities for both web and mobile applications based on conditions of the Sh... Text-based passwords are heavily used to defense for many web and mobile applications. In this paper, we investigated the patterns and vulnerabilities for both web and mobile applications based on conditions of the Shannon entropy, Guessing entropy and Minimum entropy. We show how to substantially improve upon the strength of passwords based on the analysis of text-password entropies. By analyzing the passwords datasets of Rockyou and 163.com, we believe strong password can be designed based on good usability, deployability, rememberbility, and security entropies. 展开更多
关键词 password strength security entropies password vulnerabilities
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On Clausius, Boltzmann and Shannon Notions of Entropy 被引量:1
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作者 Francisco Balibrea 《Journal of Modern Physics》 2016年第2期219-227,共9页
Discrete dynamical systems are given by the pair (X,f) where X is a compact metric space and f: X→X is a continuous map. During years, a long list of results have appeared to precise and understand what is the comple... Discrete dynamical systems are given by the pair (X,f) where X is a compact metric space and f: X→X is a continuous map. During years, a long list of results have appeared to precise and understand what is the complexity of the systems. Among them, one of the most popular is that of topological entropy. In modern applications, other conditions on X and f have been considered. For example, X can be non-compact or f can be discontinuous (only in a finite number of points and with bounded jumps on the values of f or even non-bounded jumps). Such systems are interesting from theoretical point of view in Topological Dynamics and appear frequently in applied sciences such as Electronics and Control Theory. In this paper, we are reviewing the origins of the notion of entropy and studying some developing of it leading to modern notions of entropies. At the same time, we will incorporate some mathematical foundations of such old and new ideas until the appearance of Shannon entropy. To this end, we start with the introduction for the first time of the notion of entropy in thermodynamics by R. Clausius and its evolution by L. Boltzmann until the appearing in the twenty century of Shannon and Kolmogorov-Sinai entropies and the subsequent topological entropy. In turn, such notions have evolved to other recent situations where it is necessary to give some extended versions of them adapted to new problems. Of special interest is to appreciate the connexions of the notions of entropy from Boltzmann and Shannon. Since this history is long, we will not deal with the Kolmogorov-Sinai entropy or with topological entropy and modern approaches. 展开更多
关键词 CLAUSIUS Boltzmann and Shannon entropies Information Theory
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Shannon information entropies for rectangular multiple quantum well systems with constant total lengths
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作者 M Solaimani Guo-Hua Sun Shi-Hai Dong 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第4期154-163,共10页
We first study the Shannon information entropies of constant total length multiple quantum well systems and then explore the effects of the number of wells and confining potential depth on position and momentum inform... We first study the Shannon information entropies of constant total length multiple quantum well systems and then explore the effects of the number of wells and confining potential depth on position and momentum information entropy density as well as the corresponding Shannon entropy.We find that for small full width at half maximum(FWHM) of the position entropy density,the FWHM of the momentum entropy density is large and vice versa.By increasing the confined potential depth,the FWHM of the position entropy density decreases while the FWHM of the momentum entropy density increases.By increasing the potential depth,the frequency of the position entropy density oscillation within the quantum barrier decreases while that of the position entropy density oscillation within the quantum well increases.By increasing the number of wells,the frequency of the position entropy density oscillation decreases inside the barriers while it increases inside the quantum well.As an example,we might localize the ground state as well as the position entropy densities of the1 st,2 nd,and 6 th excited states for a four-well quantum system.Also,we verify the Bialynicki–Birula–Mycieslki(BBM)inequality. 展开更多
关键词 position and momentum Shannon entropies multiple quantum well entropy densities
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IONIC ENTROPIES ON A BOND PARAMETER SCALE
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作者 周振华 《天津工业大学学报》 CAS 北大核心 1990年第2期34-37,共4页
Some expressions were proposed in the previous report to exp-ress the relation between the entropies S°<sub>298</sub> and the bond parameterZ/r in the same type of compounds.Based on this we derived a... Some expressions were proposed in the previous report to exp-ress the relation between the entropies S°<sub>298</sub> and the bond parameterZ/r in the same type of compounds.Based on this we derived a rela-tion formula for calculating the ionic entropies and established a 展开更多
关键词 BOND PARAMETERS IONIC entropies
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One Parameter Family of N-Qudit Werner-Popescu States: Bipartite Separability Using Conditional Quantum Relative Tsallis Entropy
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作者 Anantha S. Nayak Sudha   +1 位作者 A. R. Usha Devi A. K. Rajagopal 《Journal of Quantum Information Science》 2018年第1期12-23,共12页
The conditional version of sandwiched Tsallis relative entropy (CSTRE) is employed to study the bipartite separability of one parameter family of N-qudit Werner-Popescu states in their 1:N-1 partition. For all N, the ... The conditional version of sandwiched Tsallis relative entropy (CSTRE) is employed to study the bipartite separability of one parameter family of N-qudit Werner-Popescu states in their 1:N-1 partition. For all N, the strongest limitation on bipartite separability is realized in the limit and is found to match exactly with the separability range obtained using an algebraic method which is both necessary and sufficient. The theoretical superiority of using CSTRE criterion to find the bipartite separability range over the one using Abe-Rajagopal (AR) q-conditional entropy is illustrated by comparing the convergence of the parameter x with respect to q, in the implicit plots of AR q-conditional entropy and CSTRE. 展开更多
关键词 entropic SEPARABILITY Criterion q-Conditional entropies Non-Commuting Version of RELATIVE Entropy
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Statistical Inference of Truncated Weibull-Rayleigh Distribution: Its Properties and Applications
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作者 Eman H. Khalifa Dina A. Ramadan B. S. El-Desouky 《Open Journal of Modelling and Simulation》 2021年第3期281-298,共18页
<span style="font-family:Verdana;">In this paper, we derived a new distribution named as truncated Weibull Rayleigh (TW-R) distribution. Its characterization and statistical properties are obtained, su... <span style="font-family:Verdana;">In this paper, we derived a new distribution named as truncated Weibull Rayleigh (TW-R) distribution. Its characterization and statistical properties are obtained, such as reliability function, hazard function, reversed</span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">hazard rate function, cumulative hazard rate function, quantile function, rth moment, incomplete moments, Rényi and q entropies and order statistic. Parameter estimation is implemented using method of maximum-likelihood estimation and Fisher information matrix is derived. Finally, application of the presented new distribution to a real data representing the failure times of 63 airbcraft</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Windshield is given and its goodness-of-fit is demonstrated. In addition to, comparisons to other models are implemented to show the flexibility of the presented</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">model.</span></span></span> 展开更多
关键词 Rayleigh Distribution Truncated Weibull G-Family MOMENTS entropies Quantile Function Order Statistic Maximum Likelihood Estimator
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A New Approach to Time-Dependent Solutions to the Non-Linear Fokker-Planck Equations Related to Arbitrary Functions of Tsallis Entropy: A Mathematical Study and Investigation
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作者 Alireza Heidari Seyedali Vedad Mohammadali Ghorbani 《Journal of Modern Physics》 2012年第5期420-429,共10页
The following article has been retracted due to the investigation of complaints received against it. Mr. Mohammadali Ghorbani (corresponding author and also the last author) cheated the authors’ name: Alireza Heidari... The following article has been retracted due to the investigation of complaints received against it. Mr. Mohammadali Ghorbani (corresponding author and also the last author) cheated the authors’ name: Alireza Heidari and Seyedali Vedad. The scientific community takes a very strong view on this matter and we treat all unethical behavior such as plagiarism seriously. This paper published in Vol.3 No.5 420-429, 2012, has been removed from this site. 展开更多
关键词 NON-LINEAR FOKKER-PLANCK EQUATIONS TSALLIS Entropy Generalized entropies
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THE NEW MODEL FOR CALCULATION OF STANDARD ENTROPIES OF SOLID COMPOUNDS Ⅲ CALCULATION FOR STANDARD ENTROPIES OF SOLID BINARY OXIDES
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作者 Xun Min YU Yuan Li ZHAO Dao Wu YANG (Jingzhou Educalional College Hubei. 414100) 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第5期405-406,共2页
This paper establishes a new model for calculation of the standard entropies of solid binary oxides as follows: S_(29)=27.07×Φ_1+1.120×Φ_2+n_1×k×Φ, -22.19 e.u (R=0.9960) We have invesigated 103 ... This paper establishes a new model for calculation of the standard entropies of solid binary oxides as follows: S_(29)=27.07×Φ_1+1.120×Φ_2+n_1×k×Φ, -22.19 e.u (R=0.9960) We have invesigated 103 binary oxides. and found good agreemenl between estimated and experimental entropies. 展开更多
关键词 CALCULATION FOR STANDARD entropies OF SOLID BINARY OXIDES THE NEW MODEL FOR CALCULATION OF STANDARD entropies OF SOLID COMPOUNDS
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Entropy—A Universal Concept in Sciences
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作者 Vladimír Majerník 《Natural Science》 2014年第7期552-564,共13页
Entropy represents a universal concept in science suitable for quantifying the uncertainty of a series of random events. We define and describe this notion in an appropriate manner for physicists. We start with a brie... Entropy represents a universal concept in science suitable for quantifying the uncertainty of a series of random events. We define and describe this notion in an appropriate manner for physicists. We start with a brief recapitulation of the basic concept of the theory probability being useful for the determination of the concept of entropy. The history of how this concept came into its to-day exact form is sketched. We show that the Shannon entropy represents the most adequate measure of the probabilistic uncertainty of a random object. Though the notion of entropy has been introduced in classical thermodynamics as a thermodynamic state variable it relies on concepts studied in the theory of probability and mathematical statistics. We point out that whole formalisms of statistical mechanics can be rewritten in terms of Shannon entropy. The notion “entropy” is differently understood in various science disciplines: in classical physics it represents the thermodynamical state variable;in communication theory it represents the efficiency of transmission of communication;in the theory of general systems the magnitude of the configurational order;in ecology the measure for bio-diversity;in statistics the degree of disorder, etc. All these notions can be mapped on the general mathematical concept of entropy. By means of entropy, the configurational order of complex systems can be exactly quantified. Besides the Shannon entropy, there exists a class of Shannon-like entropies which converge, under certain circumstances, toward Shannon entropy. The Shannon-like entropy is sometimes easier to handle mathematically then Shannon entropy. One of the important Shannon-like entropy is well-known Tsallis entropy. The application of the Shannon and Shannon-like entropies in science is really versatile. Besides the mentioned statistical physics, they play a fundamental role in the quantum information, communication theory, in the description of disorder, etc. 展开更多
关键词 PROBABILITY UNCERTAINTY Shannon ENTROPY Shannon-Like entropies
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Multi-attribute decision making with Pythagorean fuzzy sets via conversions to intuitionistic fuzzy sets and ORESTE method 被引量:1
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作者 Zhifu Tao Jiaming Zhu +2 位作者 Ligang Zhou Jinpei Liu Huayou Chen 《Journal of Control and Decision》 EI 2021年第3期372-383,共12页
The aim of this paper is to study the conversions between Pythagorean fuzzy sets and Atanassov’s intuitionistic fuzzy sets.Besides,an ORESTE method based on multi-attribute decision making with Pythagorean fuzzy sets... The aim of this paper is to study the conversions between Pythagorean fuzzy sets and Atanassov’s intuitionistic fuzzy sets.Besides,an ORESTE method based on multi-attribute decision making with Pythagorean fuzzy sets is developed by utilising the developed conversions.In this paper,according to the geometric representations of Pythagorean fuzzy sets and Atanassov’s intuitionistic fuzzy sets,two types of conversions between the two fuzzy sets are constructed,which are further used to derive information measures include entropy and cross-entropy measures of Pythagorean fuzzy sets.Then,by combining with the ORESTE method,a direct decision procedure for multi-attribute decision making with Pythagorean fuzzy information is developed.Finally,a numerical example of the evaluation of regional energy efficiency is shown to illustrate the feasibility and validity of the developed decision procedure. 展开更多
关键词 Pythagorean fuzzy sets multi-attribute decision making Atanassov’s intuitionistic fuzzy sets ORESTE entropies
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Total versus quantum correlations in a two-mode Gaussian state 被引量:1
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作者 Jamal EI Qars 《Communications in Theoretical Physics》 SCIE CAS CSCD 2021年第5期38-45,共8页
In Li and Luo(2007 Phys.Rev.A 76032327),the inequality(1/2)T≥Q was identified as a fundamental postulate for a consistent theory of quantum versus classical correlations for arbitrary measures of total T and quantum ... In Li and Luo(2007 Phys.Rev.A 76032327),the inequality(1/2)T≥Q was identified as a fundamental postulate for a consistent theory of quantum versus classical correlations for arbitrary measures of total T and quantum Q correlations in bipartite quantum states.Besides,Hayden et al(2006 Commun.Math.Phys.26595)have conjectured that,in some conditions within systems endowed with infinite-dimensional Hilbert spaces,quantum correlations may dominate not only half of total correlations but total correlations itself.Here,in a two-mode Gaussian state,quantifying T and Q respectively by the quantum mutual information I~G and the entanglement of formation(EoF)ε_(F)^(G),we verify thatε_(F)^(G),is always less than(1/2)I_(R)^(G( when I~G andε_(F)^(G) are defined via the Rényi-2 entropy.While via the von Neumann entropy,ε_(F,V)^(G),may even dominate I_(V)^(G) itself,which partly consolidates the Hayden conjecture,and partly,provides strong evidence hinting that the origin of this counterintuitive behavior should intrinsically be related to the von Neumann entropy by which the EoFε_(F,V)^(G),is defined,rather than related to the conceptual definition of the EoFε_(F).The obtained results show that—in the special case of mixed two-mode Gaussian states—quantum entanglement can be faithfully quantified by the Gaussian Rényi-2 EoFε_(F,R)^(G),. 展开更多
关键词 ENTANGLEMENT von Neumann and Rényi-2 entropies quantum mutual information Gaussian states spontaneous emission laser
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THE ENTROPIES OF THE COLLAPSING STAR AND OF THE BLACK HOLE
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《Research in Astronomy and Astrophysics》 SCIE CAS 1982年第2期104-106,共3页
We put forth three modes of black hole formation, i.e. (1) A black hole kern forms initially inside the collapsing star. (2) The different mass shells of the collapsing star fulfils the Schwarzschild condition simulta... We put forth three modes of black hole formation, i.e. (1) A black hole kern forms initially inside the collapsing star. (2) The different mass shells of the collapsing star fulfils the Schwarzschild condition simultaneously. (3) Only the outmost mass shell of the collapsing star fulfils the Schwarzschild condition. We then calculate the entropy of the collapsing star for modes (1) and (3) and find that they are only 10-19 times the entropy of black hole. Modes (1) may be occure during the supernova explosions or galaxy explosions. Mode (3) may be occur in the formation of galactic black hole. 展开更多
关键词 MODE THE entropies OF THE COLLAPSING STAR AND OF THE BLACK HOLE STAR
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Fisher and Shannon information entropies for a noncentral inversely quadratic plus exponential Mie-type potential
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作者 Ituen B Okon Cecilia N Isonguyo +2 位作者 Akaninyene D Antia Akpan N Ikot Oyebola O Popoola 《Communications in Theoretical Physics》 SCIE CAS CSCD 2020年第6期43-56,共14页
In this work,we determine the Fisher and Shannon entropies,the expectation values and the squeeze state for a noncentral inversely quadratic plus exponential Mie-type potential analytically.The proposed potential is s... In this work,we determine the Fisher and Shannon entropies,the expectation values and the squeeze state for a noncentral inversely quadratic plus exponential Mie-type potential analytically.The proposed potential is solved under the Schr?dinger equation using a special Greene Aldrich approximation to the centrifugal term to obtain a normalised wave function within the framework of the Nikiforov–Uvarov method.Numerical results are obtained for different screening parameters:α?=?0.1,0.12 and 0.13 for varying real constant parameter(B).The numerical solutions are obtained only for ground state.The numerical results of Fisher entropy both for position and momentum spaces are in good agreement with existing literature.The normalisation constant,wave function,and probability density plots are carried out using a well designed Mathematica algorithm.The Fourier transform of position space entropy gives the momentum space entropy. 展开更多
关键词 Fisher and Shannon entropies Schr?dinger equation expectation values Nikiforov–Uvarov method
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MD模拟研究Mini-protein Chignolin去折叠过程中残基的构象熵
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作者 刘贵忠 于家峰 《德州学院学报》 2007年第6期1-4,共4页
采用分子动力学模拟方法,对Chignolin在260 K、300 K、350 K和400 K进行去折叠模拟,计算8个残基(2—9位点)的构象熵.研究发现,构象熵值可大致分为低熵组、中熵组和高熵组.影响残基熵值的因素主要为温度、残基的原子数、残基所在位点、... 采用分子动力学模拟方法,对Chignolin在260 K、300 K、350 K和400 K进行去折叠模拟,计算8个残基(2—9位点)的构象熵.研究发现,构象熵值可大致分为低熵组、中熵组和高熵组.影响残基熵值的因素主要为温度、残基的原子数、残基所在位点、与邻近残基的相互作用等.还发现残基的构象熵有短时间急剧变化——阶梯跃变的现象.这意味着蛋白质的去折叠可能是不连续的.提示蛋白质的折叠过程可能也是不连续的. 展开更多
关键词 Chignolin 构象熵 分子动力学模拟 去折叠 阶梯跃变
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二维熵图像阈值分割的快速递推算法 被引量:53
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作者 张毅军 吴雪菁 夏良正 《模式识别与人工智能》 EI CSCD 北大核心 1997年第3期259-264,共6页
阈值分割是图像分割技术的一种重要方法,在图像处理与识别中广为应用.本文提出了一种二维熵图像阈值分割的快速递推算法.实验结果表明,该二维最大熵递推算法可以有效地提高熵函数的计算速度.
关键词 二维熵 图像分割 阈值分割 递推算法 图像处理
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论熵增最小化经济与资源的可持续利用 被引量:7
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作者 苗艳青 严立冬 《中国人口·资源与环境》 CSSCI 2006年第6期40-43,共4页
经济的快速发展带来了经济系统不断的优化演变,但同时也给生态系统带来了过多的环境问题。文章从资源熵、负熵资本与资源利用的关联性入手,运用生态经济系统熵变模型,从熵经济学角度分析环境污染问题,得出这样的结论:自然界过快的熵增... 经济的快速发展带来了经济系统不断的优化演变,但同时也给生态系统带来了过多的环境问题。文章从资源熵、负熵资本与资源利用的关联性入手,运用生态经济系统熵变模型,从熵经济学角度分析环境污染问题,得出这样的结论:自然界过快的熵增超出了自然界消除熵的能力,以至于自然界没有太多排放熵的空间是造成环境危机的深层次原因。改变当前人类利用资源的方式是缓解环境危机的根本出路,而发展熵增最小化经济为缓解环境危机,实现资源的可持续利用提供了理论上的可行性。 展开更多
关键词 资源熵 负熵资本 可持续利用 熵增最小化经济
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新的价连接性指数与烃标准熵和燃烧热的相关性研究 被引量:7
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作者 堵锡华 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2001年第3期308-314,共7页
定义原子特征值 βi=(ni- 1)mi±hi。由 βi 建构新的价连接性指数 mX =∑ ( βi·βj·βk… ) 0 .5,其中 0阶指数0 X =∑ ( βi) 0 .5,1阶指数 1X =∑ ( βi·βj) 0 .5。并计算了 4个系列 72个烃分子的 0 X、1X值。... 定义原子特征值 βi=(ni- 1)mi±hi。由 βi 建构新的价连接性指数 mX =∑ ( βi·βj·βk… ) 0 .5,其中 0阶指数0 X =∑ ( βi) 0 .5,1阶指数 1X =∑ ( βi·βj) 0 .5。并计算了 4个系列 72个烃分子的 0 X、1X值。发现 mX与烃的标准熵、标准燃烧热有良好的相关性 ,相关系数均在 0 .99以上。并采用Jackknife方法对模型稳健性进行了检验。 展开更多
关键词 原子特征值 价连接性指数 标准熵 标准燃烧热 模型稳健性 定量结构-性质相关性
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KCl在混合溶剂(水和异丙醇)中的热力学性质的研究 被引量:6
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作者 王卫东 《盐湖研究》 CSCD 2004年第4期38-44,共7页
应用电导法测定了KCl在水和异丙醇混合溶剂中的活度系数,讨论了电解质溶液活度系数与浓度和温度的关系,并计算了电解质溶液在混合溶剂中的相对偏摩尔自由能、相对偏摩尔焓、相对偏摩尔熵,对其相对偏摩尔性质的某些变化规律作了初步的讨论。
关键词 混合溶剂 活度系数 热力学性质 摩尔 自由能 异丙醇 电解质溶液 电导法 用电
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