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Applying the Stefan-Boltzmann Law to a Cosmological Model (a Brief Note)
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2024年第11期1717-1722,共6页
This brief note brings the reader up-to-date with the recent successes of the new Haug-Tatum cosmology model. In particular, the significance of recent proof that the Stefan-Boltzmann law applies to such a model is em... This brief note brings the reader up-to-date with the recent successes of the new Haug-Tatum cosmology model. In particular, the significance of recent proof that the Stefan-Boltzmann law applies to such a model is emphasized and a rationale for this is given. Remarkably, the proposed solutions of this model have incorporated all 580 supernova redshifts in the Union2 database. Therefore, one can usefully apply this thermodynamic law in the form of a continually expanding black-body universe model. To our knowledge, no other cosmological model has achieved such high-precision observational correlation. 展开更多
关键词 Haug-Tatum Cosmology stefan-boltzmann law Flat Space Cosmology CMB Cosmic Thermodynamics Rh = ct Cosmology Model Black Body
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How to Predict the Temperature of the CMB Directly Using the Hubble Parameter and the Planck Scale Using the Stefan-Boltzmann Law
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作者 Espen Gaarder Haug Stéphane Wojnow 《Journal of Applied Mathematics and Physics》 2024年第10期3552-3566,共15页
Based on recent progress in quantum gravity and quantum cosmology, we are also presenting a way to estimate the temperature in the cosmos, the Hubble sphere, from a relation between the Planck temperature and the Hubb... Based on recent progress in quantum gravity and quantum cosmology, we are also presenting a way to estimate the temperature in the cosmos, the Hubble sphere, from a relation between the Planck temperature and the Hubble scale. Our analysis predicts the Hubble sphere temperature of 2.72 K with the one standard deviation confidence interval between 2.65 K and 2.80 K, which corresponds well with the measured temperature observed from the cosmic microwave background (CMB) of about 2.72 K. This adds evidence that there is a close connection between the Planck scale, gravity, and the cosmological scales as anticipated by Eddington already in 1918.1. 展开更多
关键词 CMB Temperature Hubble Parameter stefan-boltzmann law Planck Scale
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Are Black Holes 4-D Spatial Balls Filled with Black Body Radiation? Generalization of the Stefan-Boltzmann Law and Young-Laplace Relation for Spatial Radiative Transfers
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作者 Christopher Pilot 《Journal of High Energy Physics, Gravitation and Cosmology》 2019年第3期638-682,共45页
This is the first paper in a two part series on black holes. In this work, we concern ourselves with the event horizon. A second follow-up paper will deal with its internal structure. We hypothesize that black holes a... This is the first paper in a two part series on black holes. In this work, we concern ourselves with the event horizon. A second follow-up paper will deal with its internal structure. We hypothesize that black holes are 4-dimensional spatial, steady state, self-contained spheres filled with black-body radiation. As such, the event horizon marks the boundary between two adjacent spaces, 4-D and 3-D, and there, we consider the radiative transfers involving black- body photons. We generalize the Stefan-Boltzmann law assuming that photons can transition between different dimensional spaces, and we can show how for a 3-D/4-D interface, one can only have zero, or net positive, transfer of radiative energy into the black hole. We find that we can predict the temperature just inside the event horizon, on the 4-D side, given the mass, or radius, of the black hole. For an isolated black hole with no radiative heat inflow, we will assume that the temperature, on the outside, is the CMB temperature, T2 = 2.725 K. We take into account the full complement of radiative energy, which for a black body will consist of internal energy density, radiative pressure, and entropy density. It is specifically the entropy density which is responsible for the heat flowing in. We also generalize the Young- Laplace equation for a 4-D/3-D interface. We derive an expression for the surface tension, and prove that it is necessarily positive, and finite, for a 4-D/3-D membrane. This is important as it will lead to an inherently positively curved object, which a black hole is. With this surface tension, we can determine the work needed to expand the black hole. We give two formulations, one involving the surface tension directly, and the other involving the coefficient of surface tension. Because two surfaces are expanding, the 4-D and the 3-D surfaces, there are two radiative contributions to the work done, one positive, which assists expansion. The other is negative, which will resist an increase in volume. The 4-D side promotes expansion whereas the 3-D side hinders it. At the surface itself, we also have gravity, which is the major contribution to the finite surface tension in almost all situations, which we calculate in the second paper. The surface tension depends not only on the size, or mass, of the black hole, but also on the outside surface temperature, quantities which are accessible observationally. Outside surface temperature will also determine inflow. Finally, we develop a “waterfall model” for a black hole, based on what happens at the event horizon. There we find a sharp discontinuity in temperature upon entering the event horizon, from the 3-D side. This is due to the increased surface area in 4-D space, AR(4) = 2π2R3, versus the 3-D surface area, AR(3) = 4πR2. This leads to much reduced radiative pressures, internal energy densities, and total energy densities just inside the event horizon. All quantities are explicitly calculated in terms of the outside surface temperature, and size of a black hole. Any net radiative heat inflow into the black hole, if it is non-zero, is restricted by the condition that, 0cdQ/dt FR(3), where, FR(3), is the 3-D radiative force applied to the event horizon, pushing it in. We argue throughout this paper that a 3-D/3-D interface would not have the same desirable characteristics as a 4-D/3-D interface. This includes allowing for only zero or net positive heat inflow into the black hole, an inherently positive finite radiative surface tension, much reduced temperatures just inside the event horizon, and limits on inflow. 展开更多
关键词 BLACK Holes 4-D SPATIAL BALLS BLACK Body Radiation stefan-boltzmann law Young-Laplace RELATION
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General laws of funding for scientific citations:how citations change in funded and unfunded research between basic and applied sciences 被引量:1
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作者 Mario Coccia Saeed Roshani 《Journal of Data and Information Science》 CSCD 2024年第4期71-89,共19页
Purpose:The goal of this study is to analyze the relationship between funded and unfunded papers and their citations in both basic and applied sciences.Design/methodology/approach:A power law model analyzes the relati... Purpose:The goal of this study is to analyze the relationship between funded and unfunded papers and their citations in both basic and applied sciences.Design/methodology/approach:A power law model analyzes the relationship between research funding and citations of papers using 831,337 documents recorded in the Web of Science database.Findings:The original results reveal general characteristics of the diffusion of science in research fields:a)Funded articles receive higher citations compared to unfunded papers in journals;b)Funded articles exhibit a super-linear growth in citations,surpassing the increase seen in unfunded articles.This finding reveals a higher diffusion of scientific knowledge in funded articles.Moreover,c)funded articles in both basic and applied sciences demonstrate a similar expected change in citations,equivalent to about 1.23%,when the number of funded papers increases by 1%in journals.This result suggests,for the first time,that funding effect of scientific research is an invariant driver,irrespective of the nature of the basic or applied sciences.Originality/value:This evidence suggests empirical laws of funding for scientific citations that explain the importance of robust funding mechanisms for achieving impactful research outcomes in science and society.These findings here also highlight that funding for scientific research is a critical driving force in supporting citations and the dissemination of scientific knowledge in recorded documents in both basic and applied sciences.Practical implications:This comprehensive result provides a holistic view of the relationship between funding and citation performance in science to guide policymakers and R&D managers with science policies by directing funding to research in promoting the scientific development and higher diffusion of results for the progress of human society. 展开更多
关键词 Research funding CITATIONS Scientific development Science diffusion Scientific laws Power law model Matthew effect Science policy Research policy Science of science Dynamics of science Evolution of science
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Weber Law Based Approach for Multi-Class Image Forgery Detection 被引量:1
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作者 Arslan Akram Javed Rashid +3 位作者 Arfan Jaffar Fahima Hajjej Waseem Iqbal Nadeem Sarwar 《Computers, Materials & Continua》 SCIE EI 2024年第1期145-166,共22页
Today’s forensic science introduces a new research area for digital image analysis formultimedia security.So,Image authentication issues have been raised due to the wide use of image manipulation software to obtain a... Today’s forensic science introduces a new research area for digital image analysis formultimedia security.So,Image authentication issues have been raised due to the wide use of image manipulation software to obtain an illegitimate benefit or createmisleading publicity by using tempered images.Exiting forgery detectionmethods can classify only one of the most widely used Copy-Move and splicing forgeries.However,an image can contain one or more types of forgeries.This study has proposed a hybridmethod for classifying Copy-Move and splicing images using texture information of images in the spatial domain.Firstly,images are divided into equal blocks to get scale-invariant features.Weber law has been used for getting texture features,and finally,XGBOOST is used to classify both Copy-Move and splicing forgery.The proposed method classified three types of forgeries,i.e.,splicing,Copy-Move,and healthy.Benchmarked(CASIA 2.0,MICCF200)and RCMFD datasets are used for training and testing.On average,the proposed method achieved 97.3% accuracy on benchmarked datasets and 98.3% on RCMFD datasets by applying 10-fold cross-validation,which is far better than existing methods. 展开更多
关键词 Copy-Move and splicing non-overlapping block division texture features weber law spatial domain xgboost
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基于多尺度Laws纹理能量和低秩分解的织物疵点检测算法
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作者 王振华 张周强 +1 位作者 昝杰 刘江浩 《纺织学报》 EI CAS CSCD 北大核心 2024年第4期96-104,共9页
为提高织物疵点检测算法对简单纹理织物、模式纹理织物及条纹纹理织物检测时的普适性和准确性,提出了一种基于多尺度Laws纹理能量和低秩分解的织物疵点检测算法。首先,对织物图像进行直方图均衡化并将处理后的图像均匀划分为子图像块;其... 为提高织物疵点检测算法对简单纹理织物、模式纹理织物及条纹纹理织物检测时的普适性和准确性,提出了一种基于多尺度Laws纹理能量和低秩分解的织物疵点检测算法。首先,对织物图像进行直方图均衡化并将处理后的图像均匀划分为子图像块;其次,对每个子图像块提取28个纹理能量特征(利用7个Laws滤波模板在4个尺度上提取),计算所有子图像块提取到的特征均值并组成特征矩阵;然后,利用特征矩阵构建低秩分解模型,通过方向交替方法(ADM)优化求解,得到低秩部分和稀疏部分;最后,由稀疏部分生成疵点显著图,采用迭代阈值分割法对其进行分割,得到织物疵点检测结果。为验证该算法的有效性,在织物图像数据集选取了包含错纬、断经、跳花、破洞等常见疵点的织物图像,并将实验结果与已有3种算法进行了对比。实验结果表明,该算法在简单纹理织物、模式纹理织物及条纹纹理织物检测上具有更好的普适性和准确性,且检测效率具有一定优势。 展开更多
关键词 织物疵点 疵点检测 laws纹理 纹理能量 特征提取 矩阵低秩分解
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Scaling Laws Behind Penetrative Turbulence:History and Perspectives
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作者 Zijing DING Ruiqi HUANG Zhen OUYANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第10期1881-1900,共20页
An unstably stratified flow entering into a stably stratified flow is referred to as penetrative convection,which is crucial to many physical processes and has been thought of as a key factor for extreme weather condi... An unstably stratified flow entering into a stably stratified flow is referred to as penetrative convection,which is crucial to many physical processes and has been thought of as a key factor for extreme weather conditions.Past theoretical,numerical,and experimental studies on penetrative convection are reviewed,along with field studies providing insights into turbulence modeling.The physical factors that initiate penetrative convection,including internal heat sources,nonlinear constitutive relationships,centrifugal forces and other complicated factors are summarized.Cutting-edge methods for understanding transport mechanisms and statistical properties of penetrative turbulence are also documented,e.g.,the variational approach and quasilinear approach,which derive scaling laws embedded in penetrative turbulence.Exploring these scaling laws in penetrative convection can improve our understanding of large-scale geophysical and astrophysical motions.To better the model of penetrative turbulence towards a practical situation,new directions,e.g.,penetrative convection in spheres,and radiation-forced convection,are proposed. 展开更多
关键词 thermal convection penetrative convection scaling law TURBULENCE
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Closed-form guidance law for velocity maximization with impact angle constraint
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作者 ZHANG Jiahui WEN Qiuqiu 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1295-1303,共9页
Final velocity and impact angle are critical to missile guidance.Computationally efficient guidance law with compre-hensive consideration of the two performance merits is challeng-ing yet remains less addressed.Theref... Final velocity and impact angle are critical to missile guidance.Computationally efficient guidance law with compre-hensive consideration of the two performance merits is challeng-ing yet remains less addressed.Therefore,this paper seeks to solve a type of optimal control problem that maximizes final velocity subject to equality point constraint of impact angle con-straint.It is proved that the crude problem of maximizing final velocity is equivalent to minimizing a quadratic-form cost of cur-vature.The closed-form guidance law is henceforth derived using optimal control theory.The derived analytical guidance law coincides with the widely-used optimal guidance law with impact angle constraint(OGL-IAC)with a set of navigation parameters of two and six.On this basis,the optimal emission angle is determined to further increase the final velocity.The derived optimal value depends solely on the initial line-of-sight angle and impact angle constraint,and thus practical for real-world appli-cations.The proposed guidance law is validated by numerical simulation.The results show that the OGL-IAC is superior to the benchmark guidance laws both in terms of final velocity and missing distance. 展开更多
关键词 MISSILE guidance law proportional-navigation guidance impact angle
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Nonuniform Dependence on the Initial Data for Solutions of Conservation Laws
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作者 John M.Holmes Barbara Lee Keyfitz 《Communications on Applied Mathematics and Computation》 EI 2024年第1期489-500,共12页
In this paper,we study systems of conservation laws in one space dimension.We prove that for classical solutions in Sobolev spaces H^(s),with s>3/2,the data-to-solution map is not uniformly continuous.Our results a... In this paper,we study systems of conservation laws in one space dimension.We prove that for classical solutions in Sobolev spaces H^(s),with s>3/2,the data-to-solution map is not uniformly continuous.Our results apply to all nonlinear scalar conservation laws and to nonlinear hyperbolic systems of two equations. 展开更多
关键词 Conservation laws Data-to-solution map Nonuniform dependence
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Triple reverse order law for the Drazin inverse
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作者 WANG Hua ZHONG Cheng-cheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期55-68,共14页
In this paper,we investigate the reverse order law for Drazin inverse of three bound-ed linear operators under some commutation relations.Moreover,the Drazin invertibility of sum is also obtained for two bounded linea... In this paper,we investigate the reverse order law for Drazin inverse of three bound-ed linear operators under some commutation relations.Moreover,the Drazin invertibility of sum is also obtained for two bounded linear operators and its expression is presented. 展开更多
关键词 Drazin inverse reverse order law space decomposition
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Literature overview of basic characteristics and flotation laws of flocs
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作者 Wanzhong Yin Yu Xie Zhanglei Zhu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期943-958,共16页
Flocculation flotation is the most efficient method for recovering fine-grained minerals,and its essence lies in flotation and recovery of flocs.Fundamental physical characteristics of flocs are mainly determined by t... Flocculation flotation is the most efficient method for recovering fine-grained minerals,and its essence lies in flotation and recovery of flocs.Fundamental physical characteristics of flocs are mainly determined by their apparent particle size and structure(density and morphology).Substantial researches have been conducted regarding the effect of floc characteristics on particle settling and water treatment.However,the influence of floc characteristics on flotation has not been widely studied.Based on the floc formation and flocculation flotation,this study reviews the fundamental physical characteristics of flocs from the perspectives of floc particle size and structure,summarizing the interaction between floc particle size and structure.Moreover,it thoroughly discusses the effect of floc particle size and structure on floc floatability,further revealing the influence of floc characteristics on bubble collision and adhesion and elucidating the mechanisms of interaction between flocs and bubbles.Thus,it is observed that floc particle size is not the only factor influencing flocculation flotation.Within the appropriate apparent particle size range,flocs with a compact structure exhibit higher efficiency in bubble collision and adhesion during flotation,thereby resulting in enhanced flotation performance.This study aims to provide a reference for flocculation flotation,targeting the development of more efficient and refined flocculation flotation processes in the future. 展开更多
关键词 FLOCS basic characteristics particle size and structure flotation laws BUBBLES
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Dimension by Dimension Finite Volume HWENO Method for Hyperbolic Conservation Laws
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作者 Feng Zheng Jianxian Qiu 《Communications on Applied Mathematics and Computation》 EI 2024年第1期605-624,共20页
In this paper,we propose a finite volume Hermite weighted essentially non-oscillatory(HWENO)method based on the dimension by dimension framework to solve hyperbolic conservation laws.It can maintain the high accuracy ... In this paper,we propose a finite volume Hermite weighted essentially non-oscillatory(HWENO)method based on the dimension by dimension framework to solve hyperbolic conservation laws.It can maintain the high accuracy in the smooth region and obtain the high resolution solution when the discontinuity appears,and it is compact which will be good for giving the numerical boundary conditions.Furthermore,it avoids complicated least square procedure when we implement the genuine two dimensional(2D)finite volume HWENO reconstruction,and it can be regarded as a generalization of the one dimensional(1D)HWENO method.Extensive numerical tests are performed to verify the high resolution and high accuracy of the scheme. 展开更多
关键词 Finite volume Dimension by dimension HWENO Hyperbolic conservation laws
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On the Use of Monotonicity-Preserving Interpolatory Techniques in Multilevel Schemes for Balance Laws
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作者 Antonio Baeza Rosa Donat Anna Martinez-Gavara 《Communications on Applied Mathematics and Computation》 EI 2024年第2期1319-1341,共23页
Cost-effective multilevel techniques for homogeneous hyperbolic conservation laws are very successful in reducing the computational cost associated to high resolution shock capturing numerical schemes.Because they do ... Cost-effective multilevel techniques for homogeneous hyperbolic conservation laws are very successful in reducing the computational cost associated to high resolution shock capturing numerical schemes.Because they do not involve any special data structure,and do not induce savings in memory requirements,they are easily implemented on existing codes and are recommended for 1D and 2D simulations when intensive testing is required.The multilevel technique can also be applied to balance laws,but in this case,numerical errors may be induced by the technique.We present a series of numerical tests that point out that the use of monotonicity-preserving interpolatory techniques eliminates the numerical errors observed when using the usual 4-point centered Lagrange interpolation,and leads to a more robust multilevel code for balance laws,while maintaining the efficiency rates observed forhyperbolic conservation laws. 展开更多
关键词 Hyperbolic balance laws Well-balanced schemes Multilevel schemes Harten's multiresolution
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Distribution law and susceptibility of geohazards across a gradient belt of the Western Sichuan Plateau
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作者 LI Tianbin WANG Jianfeng +4 位作者 HE Chaoyang MENG Lubo LI Chaofei MA Junjie WEI Daqiang 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1849-1867,共19页
Across a gradient belt of the Western Sichuan Plateau,geohazards have seriously limited economic and social development.According to incomplete statistics,15,673 geohazards have been recorded in the study area.In orde... Across a gradient belt of the Western Sichuan Plateau,geohazards have seriously limited economic and social development.According to incomplete statistics,15,673 geohazards have been recorded in the study area.In order to mitigate the threat of geohazards to human engineering activities in the region,an overall understanding of the distribution pattern of geohazards and susceptibility assessment are necessary.In this paper,a gradient belt of the Western Sichuan Plateau and its zoning criteria were defined.Subsequently,on the basis of relief amplitude,distance to faults,rainfall,and human activities,three indicators of endogenic process were introduced:Bouguer gravity anomaly gradient,vertical deformation gradient,and horizontal deformation gradient.Thereafter,the distribution patterns of geohazards were investigated through mathematical statistics and ArcGIS software.By randomly selecting 10,449 hazards,a geohazard susceptibility map was generated using the Information Value(IV)model.Finally,the IV model was validated against 5224 hazards using the Area Under Curve(AUC)method.The results show that 47.6%of the geohazards were distributed in the zone of steep slope.Geohazards showed strong responses to distance to faults,human activities,and annual rainfall.The distribution of geohazards in the gradient belt of the Western Sichuan Plateau is more sensitive to vertical internal dynamics factors(such as vertical deformation gradient and Bouguer gravity anomaly gradient)without any apparent sensitivity to horizontal internal dynamics factors.The areas of high and very-high risk account for up to 32.22%,mainly distributed in the Longmenshan and Anning River faults.According to the AUC plot,the success rate of the IV model for generating the susceptibility map is 76%.This susceptibility map and geohazard distribution pattern can provide a reference for geological disaster monitoring,preparation of post-disaster emergency measures,and town planning. 展开更多
关键词 Gradient belt GEOHAZARDS Distribution law Bouguer Gravity anomaly gradient Vertical deformation gradient SUSCEPTIBILITY
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Nuclear magnetic resonance experiments on the time-varying law of oil viscosity and wettability in high-multiple waterflooding sandstone cores
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作者 JIA Hu ZHANG Rui +2 位作者 LUO Xianbo ZHOU Zili YANG Lu 《Petroleum Exploration and Development》 SCIE 2024年第2期394-402,共9页
A simulated oil viscosity prediction model is established according to the relationship between simulated oil viscosity and geometric mean value of T2spectrum,and the time-varying law of simulated oil viscosity in por... A simulated oil viscosity prediction model is established according to the relationship between simulated oil viscosity and geometric mean value of T2spectrum,and the time-varying law of simulated oil viscosity in porous media is quantitatively characterized by nuclear magnetic resonance(NMR)experiments of high multiple waterflooding.A new NMR wettability index formula is derived based on NMR relaxation theory to quantitatively characterize the time-varying law of rock wettability during waterflooding combined with high-multiple waterflooding experiment in sandstone cores.The remaining oil viscosity in the core is positively correlated with the displacing water multiple.The remaining oil viscosity increases rapidly when the displacing water multiple is low,and increases slowly when the displacing water multiple is high.The variation of remaining oil viscosity is related to the reservoir heterogeneity.The stronger the reservoir homogeneity,the higher the content of heavy components in the remaining oil and the higher the viscosity.The reservoir wettability changes after water injection:the oil-wet reservoir changes into water-wet reservoir,while the water-wet reservoir becomes more hydrophilic;the degree of change enhances with the increase of displacing water multiple.There is a high correlation between the time-varying oil viscosity and the time-varying wettability,and the change of oil viscosity cannot be ignored.The NMR wettability index calculated by considering the change of oil viscosity is more consistent with the tested Amott(spontaneous imbibition)wettability index,which agrees more with the time-varying law of reservoir wettability. 展开更多
关键词 SANDSTONE high-multiple waterflooding nuclear magnetic resonance oil viscosity rock wettability time-varying law
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Malus’ Law Derived from Deterministic Particle Behavior
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作者 Peter Schuttevaar 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期958-966,共9页
A polarized beam of energy is usually interpreted as a set of particles, all having the same polarization state. Difference in behavior between the one and the other particle is then explained by a number of counter-i... A polarized beam of energy is usually interpreted as a set of particles, all having the same polarization state. Difference in behavior between the one and the other particle is then explained by a number of counter-intuitive quantum mechanical concepts like probability distribution, superposition, entanglement and quantized spin. Alternatively, I propose that a polarized beam is composed of a set of particles with a cosine distribution of polarization angles within a polarization area. I show that Malus’ law for the intensity of a beam of polarized light can be derived in a straightforward manner from this distribution. I then show that none of the above-mentioned counter-intuitive concepts are necessary to explain particle behavior and that the ontology of particles, passing through a polarizer, can be easily and intuitively understood. I conclude by formulating some questions for follow-up research. 展开更多
关键词 Quantum Mechanics BELL Malus law SUPERPOSITION ENTANGLEMENT Quantum Fields Spin Hidden Variables LOCALITY NON-LOCALITY
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Rate Law for Photoelectrochemical Water Splitting Over CuO
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作者 Bo-Yuan Gao Wen-HuaLeng 《电化学(中英文)》 CAS 北大核心 2024年第8期17-27,共11页
Photocatalytic splitting of water over p-type semiconductors is a promising strategy for production of hydrogen.However,the determination of rate law is rarely reported.To this purpose,copper oxide(CuO)is selected as ... Photocatalytic splitting of water over p-type semiconductors is a promising strategy for production of hydrogen.However,the determination of rate law is rarely reported.To this purpose,copper oxide(CuO)is selected as a model photocathode in this study,and the photogenerated surface charge density,interfacial charge transfer rate constant and their relation to the water reduction rate(in terms of photocurrent)were investigated by a combination of(photo)electrochemical techniques.The results showed that the charge transfer rate constant is exponential-dependent on the surface charge density,and that the photocurrent equals to the product of the charge transfer rate constant and surface charge density.The reaction is first-order in terms of surface charge density.Such an unconventional rate law contrasts with the reports in literature.The charge density-dependent rate constant results from the Fermi level pinning(i.e.,Galvani potential is the main driving force for the reaction)due to accumulation of charge in the surface states and/or Frumkin behavior(i.e.,chemical potential is the main driving force).This study,therefore,may be helpful for further investigation on the mechanism of hydrogen evolution over a CuO photocathode and for designing more efficient CuO-based photocatalysts. 展开更多
关键词 CUO Photoelectrochemical water splitting Electrochemical impedance spectroscopy Rate law Kinetics of photogenerated carriers
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Development and Application of a Power Law Constitutive Model for Eddy Current Dampers
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作者 Longteng Liang Zhouquan Feng +2 位作者 Hongyi Zhang Zhengqing Chen Changzhao Qian 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2403-2419,共17页
Eddy current dampers (ECDs) have emerged as highly desirable solutions for vibration control due to theirexceptional damping performance and durability. However, the existing constitutive models present challenges tot... Eddy current dampers (ECDs) have emerged as highly desirable solutions for vibration control due to theirexceptional damping performance and durability. However, the existing constitutive models present challenges tothe widespread implementation of ECD technology, and there is limited availability of finite element analysis (FEA)software capable of accurately modeling the behavior of ECDs. This study addresses these issues by developing anewconstitutivemodel that is both easily understandable and user-friendly for FEAsoftware. By utilizing numericalresults obtained from electromagnetic FEA, a novel power law constitutive model is proposed to capture thenonlinear behavior of ECDs. The effectiveness of the power law constitutive model is validated throughmechanicalproperty tests and numerical seismic analysis. Furthermore, a detailed description of the application process ofthe power law constitutive model in ANSYS FEA software is provided. To facilitate the preliminary design ofECDs, an analytical derivation of energy dissipation and parameter optimization for ECDs under harmonicmotionis performed. The results demonstrate that the power law constitutive model serves as a viable alternative forconducting dynamic analysis using FEA and optimizing parameters for ECDs. 展开更多
关键词 Eddy current damper constitutive model finite element analysis vibration control power law constitutive model
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Two innovative equivalent statements of the third law of thermodynamics
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作者 陈晓航 周颖慧 陈金灿 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期324-328,共5页
It is found from textbooks and literature that there are three different statements for the third law of thermodynamics,i.e., the Nernst theorem, the unattainability statement of absolute zero temperature, and the hea... It is found from textbooks and literature that there are three different statements for the third law of thermodynamics,i.e., the Nernst theorem, the unattainability statement of absolute zero temperature, and the heat capacity statement. It is pointed out that such three statements correspond to three thermodynamic parameters, which are, respectively, the entropy,temperature, and heat capacity, and can be obtained by extrapolating the experimental results of different parameters at ultralow temperatures to absolute zero. It is expounded that because there is no need for additional assumptions in the derivation of the Nernst equation, the Nernst theorem should be renamed as the Nernst statement. Moreover, it is proved that both the Nernst statement and the heat capacity statement are mutually deducible and equivalent, while the unattainability of absolute zero temperature is only a corollary of the Nernst statement or the heat capacity statement so that it is unsuitably referred to as one statement of the third law of thermodynamics. The conclusion is that the Nernst statement and the heat capacity statement are two equivalent statements of the third law of thermodynamics. 展开更多
关键词 Nernst statement heat capacity statement Nernst theorem absolute zero temperature the third law of thermodynamics
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The Rule of Law is the Most Important Means of Human Rights Protection
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作者 马怀德 CHEN Feng 《The Journal of Human Rights》 2024年第1期80-82,共3页
Today,we are here to commemorate the 75^(th) anniversary of the adoption of the Universal Declaration of Human Rights.In this Declaration,which consists of only30 articles,seven articles are related to the constitutio... Today,we are here to commemorate the 75^(th) anniversary of the adoption of the Universal Declaration of Human Rights.In this Declaration,which consists of only30 articles,seven articles are related to the constitution,law,court,and the rule of law,making it a declaration filled with the rule of law.Coincidentally,today is also the 10^(th) National Constitution Day of China.Nineteen years ago,“the state respects and protects human rights”was enshrined in the Constitution,becoming a constitutional principle.Since then,human rights protection in China has been based on fundamental law. 展开更多
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