期刊文献+
共找到13篇文章
< 1 >
每页显示 20 50 100
熵概念与Clausius不等式推导方式的教学探讨 被引量:5
1
作者 苏铁健 谭成文 《化工高等教育》 2013年第3期82-83,105,共3页
本文介绍了一种在教学上利用热力学第二定律及理想气体的状态方程直接导出熵的简单方法,利用系统过程中环境压强与系统体积变化的乘积小于等于系统压强与系统体积变化的乘积的关系,直接导出Clausius不等式。该教学方法还可引导学生找出... 本文介绍了一种在教学上利用热力学第二定律及理想气体的状态方程直接导出熵的简单方法,利用系统过程中环境压强与系统体积变化的乘积小于等于系统压强与系统体积变化的乘积的关系,直接导出Clausius不等式。该教学方法还可引导学生找出另外一个新的热力学状态函数。 展开更多
关键词 热力学第二定律 clausius不等式
在线阅读 下载PDF
用熵方程证明全不可逆循环揭示的Clausius方程式
2
作者 杨吉青 于俐 国文学 《东北电力学院学报》 2002年第3期5-7,共3页
利用不可逆循环图代替传统的半不可逆循环图推导出Clausius积分式 ,并用熵方程证明之 。
关键词 熵方程 不可逆循环 clausius方程式 熵参数 工程热力学
在线阅读 下载PDF
On Clausius’, Post-Clausius’, and Negentropic Thermodynamics
3
作者 José C. Íñiguez 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第4期1425-1458,共34页
The evidence here provided shows that the thermodynamics of the second law, as currently understood, originated in a correction of the flaws affecting Clausius original work on this matter. The body of knowledge emerg... The evidence here provided shows that the thermodynamics of the second law, as currently understood, originated in a correction of the flaws affecting Clausius original work on this matter. The body of knowledge emerging from this correction has been here called post-Clausius’ thermodynamics. The said corrections, carried on with the intended goal of preserving the validity of Clausius’ main result, namely the law of increasing entropy, made use of a number of counterintuitive or logically at fault notions. A joint revision of Clausius’ and post-Clausius’ work on the second law, carried on retaining some of Clausius original notions, and disregarding others introduced by post-Clausius thermodynamics, led this author to results in direct contradiction to the law of increasing entropy. Among the key results coming out of this work we find the one stating that the total-entropy change for spontaneous thermodynamic processes is the result of the summation of the opposite-sign contributions coming from the entropic (energy degrading) and negentropic (energy upgrading) changes subsumed by any such process. These results also show, via the total-entropy change for a non-reversible heat engine, that negentropic thermodynamics subsumes post-Clausius thermodynamics as a special case. 展开更多
关键词 clausius Entropy Law in Contradiction with Its Premises Post-clausius Thermodynamics Emerges from the Biased Correction of the Flaws in clausius Entropy Law Negentropic Thermodynamics and the Transformation of Heat into Work as a Negentropic Process
在线阅读 下载PDF
On Clausius, Boltzmann and Shannon Notions of Entropy 被引量:1
4
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
在线阅读 下载PDF
New Method Proving Clausius Inequality
5
作者 Chengshu Jin 《Journal of Modern Physics》 2020年第10期1576-1588,共13页
It is impossible that proving the internal energy change has the relations with volume and pressure. About the second law of thermodynamics, many mistakes of formulations need to be put right and modified, and many ne... It is impossible that proving the internal energy change has the relations with volume and pressure. About the second law of thermodynamics, many mistakes of formulations need to be put right and modified, and many new concepts are surveyed too. The equality and inequality on the ratios of internal energy change to temperature and work to temperature are discussed. The relation between the reversible paths and their realistic paths is also researched. In an isothermal process, the internal energy change for the gases is equal to zero, but the internal energy change is not equal to zero for the phase transition or chemical reaction. The Clausius inequality can be derived from the equation calculating the internal energy change in mathematics;it is the new method proving the Clausius inequality. These change laws of thermodynamics could be applied to the gravitational field and mechanical motion and so on. 展开更多
关键词 First Law of Thermodynamics clausius Inequality Internal Energy Change Chemical Reaction Gravitational Field
在线阅读 下载PDF
开放系统中Clausius不等式的研究
6
作者 朱文涛 邱新平 《清华大学学报(自然科学版)》 EI CAS CSCD 北大核心 2000年第2期29-31,共3页
为得到普遍化的 Clausius不等式 ,通过引入附加项 ,将原不等式由封闭系统推广到任意系统。讨论了该不等式与几个重要热力学判据的关系。以稳定流动系统为例 ,用所提出的 Clausius不等式计算电功。并将计算结果与传统计算方法进行比较 ,... 为得到普遍化的 Clausius不等式 ,通过引入附加项 ,将原不等式由封闭系统推广到任意系统。讨论了该不等式与几个重要热力学判据的关系。以稳定流动系统为例 ,用所提出的 Clausius不等式计算电功。并将计算结果与传统计算方法进行比较 ,结果表明所提出的 Clausius不等式是正确的。 展开更多
关键词 开放系统 clausius不等式 热力学判据
原文传递
基于传热学原理研究中药材干燥数学模型及参数分析 被引量:1
7
作者 熊耀坤 何雁 +2 位作者 黄恺 杜焰 冯怡 《世界科学技术-中医药现代化》 北大核心 2012年第6期2183-2186,共4页
目的:建立中药材干燥数学模型,为优化干燥工艺提供理论依据。方法:运用传热学原理,探求中药材干燥过程中影响因数及能量变化过程,建立中药材干燥数学模型,并对参数进行分析。结果:现有中药材的干燥研究多为经验知识的总结,在干燥方法、... 目的:建立中药材干燥数学模型,为优化干燥工艺提供理论依据。方法:运用传热学原理,探求中药材干燥过程中影响因数及能量变化过程,建立中药材干燥数学模型,并对参数进行分析。结果:现有中药材的干燥研究多为经验知识的总结,在干燥方法、工艺及设备的选择上存在很大的盲目性。本文量化了中药材干燥过程,建立起中药材干燥数学模型,建立起干燥条件参数:热传导参数C、热辐射参数D、为热交换参数E,用于评价干燥设备的干燥性能;建立起干燥物性参数:孔隙率Φ、比热Cp、药材表面积S等,用于评价药材可干燥能力。结论:加强中药材干燥基础理论的研究,为选择合理的干燥方法、设备及工艺参数,提高干燥效率,降低能耗提供了新的方法和思路。 展开更多
关键词 中药材 干燥 数学模型 clausius—Clapeyron方程
暂未订购
热力学第二定律文字表述的应用与熵函数 被引量:3
8
作者 高贵军 《张家口师专学报》 2003年第6期49-52,共4页
热力学第二定律是用来判断过程的方向和限度的,在教学中主要介绍Clausius不等式的应用.对第二定律文字表述的应用涉及很少.文章主要介绍了热力学第二定律文字表述的应用和引出熵函数概念的必要性.
关键词 热力学第二定律 文字表述 熵函数 clausius不等式
在线阅读 下载PDF
通过实例引入熵函数及相关概念的方法初探 被引量:1
9
作者 魏玮 邸静 肖岭梅 《首都师范大学学报(自然科学版)》 2013年第1期37-40,共4页
熵是物理化学中的一个非常重要的概念,准确地理解和掌握熵的概念对学好整门课程和培养学生科学的思维方法至关重要.本文探讨在课堂讲解中使用具体实例引入熵函数并推导出Clausius不等式的教学方法,帮助学生更直观地了解其重要的物理意义... 熵是物理化学中的一个非常重要的概念,准确地理解和掌握熵的概念对学好整门课程和培养学生科学的思维方法至关重要.本文探讨在课堂讲解中使用具体实例引入熵函数并推导出Clausius不等式的教学方法,帮助学生更直观地了解其重要的物理意义,从而避免了直接引入物理名词的生硬和严格数学推导的繁琐抽象等缺陷. 展开更多
关键词 熵函数 clausius不等式 物理化学教学
在线阅读 下载PDF
Thermodynamics of the Apparent Horizon in FRW Universe with Massive Gravity 被引量:1
10
作者 李辉 张益 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第7期28-36,共9页
Applying Clausius relation with energy-supply defined by the unified first law of thermodynamics formalism to the apparent horizon of a massive gravity model in cosmology proposed lately, the corrected entropic formul... Applying Clausius relation with energy-supply defined by the unified first law of thermodynamics formalism to the apparent horizon of a massive gravity model in cosmology proposed lately, the corrected entropic formula of the apparent horizon is obtaJned with the help of the modified Friedmann equations. This entropy-area relation, together with the identified Misner-Sharp internal energy, verifies the first law of thermodynamics for the apparent horizon with a volume change term for consistency. On the other hand, by means of the corrected entropy-area formula and the Clausius relation δQ = T dS, where the heat flow δQ is the energy-supply of pure matter projecting on the vector ξ tangent to the apparent horizon and should be looked on as the amount of energy crossing the apparent horizon during the time interval dt and the temperature of the apparent horizon for energy crossing during the same interval is 1/(2πτA), the modified Friedmann equations governing the dynamical evolution of the universe are reproduced with the known energy density and pressure of massive graviton. The integration constant is found to correspond to a cosmological term which could be absorbed into the energy density of matter. Having established the correspondence of massive cosmology with the unified first law of thermodynamics on the apparent horizon, the validity of the generalized second law of thermodynamics is also discussed by assuming the thermal equilibrium between the apparent horizon and the matter field bounded by the apparent horizon. It is found that, in the limit Hc → 0, which recovers the Minkowski reference metric solution in the fiat case, the generalized second law of thermodynamics holds if α3 + 4α4 〈 0. Without this condition, even for the simplest model of dRGT massive cosmology with α3= α4 = 0, the generalized second law of thermodynamics could be violated. 展开更多
关键词 unified first law of thermodynamics clausius relation dRGT massive gravity generalized secondlaw of thermodynamics
原文传递
Thermodynamical Aspects of Modified Holographic Dark Energy Model
11
作者 李辉 张益 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第7期97-101,共5页
We investigate the unified first law and the generalized second law in a modified holographic dark energy model. The thermodynamical analysis on the apparent horizon can work and the corresponding entropy formula is e... We investigate the unified first law and the generalized second law in a modified holographic dark energy model. The thermodynamical analysis on the apparent horizon can work and the corresponding entropy formula is extracted from the systematic algorithm. The entropy correction term depends on the extra-dimension number of the brane as expected, but the interplay between the correction term and the extra dimensions is more complicated. With the unified first law of thermodynamics well-founded, the generalized second law of thermodynamics is discussed and it is found that the second law can be violated in certain circumstances. Particularly, if the number of the extra dimensions is larger than one, the generalized law of thermodynamics is always satisfied; otherwise, the validity of the second law can only be guaranteed with the Hubble radius greatly smaller than the crossover scale rcof the 5-dimensional DGP model. 展开更多
关键词 MODIFIED holographic DARK energy unified first LAW of THERMODYNAMICS clausius relation generalized second LAW of THERMODYNAMICS extra-dimension
原文传递
Relationship between Extreme Precipitation and Temperature in Two Different Regions:The Tibetan Plateau and Middle–East China 被引量:1
12
作者 Rui WANG Tao XIAN +7 位作者 Mengxiao WANG Fengjiao CHEN Yuanjian YANG Xiangdong ZHANG Rui LI Lei ZHONG Chun ZHAO Yunfei FU 《Journal of Meteorological Research》 SCIE CSCD 2019年第5期870-884,共15页
The change of extreme precipitation with temperature has regional characteristics in the context of global warming.In this study, radiosonde data, co-located rain gauge(RG) observations, and Tropical Rainfall Measurin... The change of extreme precipitation with temperature has regional characteristics in the context of global warming.In this study, radiosonde data, co-located rain gauge(RG) observations, and Tropical Rainfall Measuring Mission(TRMM) precipitation radar(PR) products are used to explore the relationship between extreme precipitation intensity and near-surface temperature in Middle–East China(MEC) and the eastern Tibetan Plateau(TP) during1998–2012. The results show that extreme precipitation intensity increases with increasing temperature at an approximate Clausius–Clapeyron(C–C) rate(i.e., water vapor increases by 7% as temperature increases by 1°C based on the C–C equation) in MEC and TP, but the rate of increase is larger in TP than in MEC. This is probably because TP(MEC) is featured with deep convective(stratiform) precipitation, which releases more(less) latent heat and strengthens the convection intensity on a shorter(longer) timescale. It is also found that when temperature is higher than 25°C(15°C) in MEC(TP), the extreme precipitation intensity decreases with rise of temperature, suggesting that the precipitation intensity does not always increase with warming. In this case, the limited atmospheric humidity and precipitable water could be the primary factors for the decrease in extreme precipitation intensity at higher temperatures. 展开更多
关键词 EXTREME precipitation clausius–Clapeyron(C–C) rate temperature humidity precipitable water
原文传递
The Generalized Thermodynamic Temperature and the New Expressions of the First and the Second Law of Thermodynamics 被引量:3
13
作者 HU Yacai CHEN Qi HU Yayuan 《Journal of Thermal Science》 SCIE EI CAS CSCD 2016年第1期1-6,共6页
The classical thermodynamics reflects the significant relationship between the heat and the temperature. On the basis of the relationships, according to the mathematical derivation, this paper structures the conceptio... The classical thermodynamics reflects the significant relationship between the heat and the temperature. On the basis of the relationships, according to the mathematical derivation, this paper structures the conceptions of generalized heat, generalized thermodynamic temperature, generalized entropy and so on. The series of conceptions in the classical thermodynamics is merely a special case of the generalized thermodynamics. Based on these conceptions of generalized thermodynamics, this paper presents the new expressions of the first law and the second law of thermodynamics. In other words, these expressions are endued with new explanations. The Eq. LZ = kTS given by this paper provides theoretical basis for these new expressions. 展开更多
关键词 Generalized thermodynamic temperature First law of thermodynamics Second law of thermodynamics Generalized Carnot cycle Generalized clausius inequality
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部