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Journal of Modern Physics 2024年第1期15卷 1-50页

作者： Michele Nardelli Amos S. Kubeka Alizera Amani Dipartimento di Scienze della Terra Università degli Studi di Napoli Federico II Naples Italy Department of Mathematical Sciences University of South Africa Unisa South Africa Department of Physics Ayatollah Amoli Branch Islamic Azad University Amol Iran

In this paper, we analyze the enthalpy, enthalpy energy density, thermodynamic volume, and the equation of state of a modified white hole. We obtain new possible mathematical connections with some sectors of Number Theory, Ramanujan Recurring Numbers, DN Constant and String Theory, that enable us to extract the quantum geometrical properties of these thermodynamic equations and the implication to the quantum vacuum spacetime geometry of our early universe as they act as the constraints to the nature of quantum gravity of the universe.

关键词： Number Theory Ramanujan Recurring Numbers DN Constant String Theory Loop Quantum Gravity Matter Creation enthalpy Energy Density Thermodynamic Volume enthalpy

enthalpy induced phase partition toward hierarchical,nanostructured high-entropy alloys

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Nano Research 2022年第6期15卷 4893-4901页

作者： Rong Guo Lanlan Yu Zhenyu Liu Jie Pan Yonggang Yao Lin Liu State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Heterogeneous nanostructured metals are emerging strategies for achieving both high strength and ductility,which are particularly attractive for high entropy alloys(HEAs)to combine the synergistic enhancements from multielement composition,grain boundaries,and heterogeneity effects.However,the construction of heterogeneous nanostructured HEAs remains elusive and can involve delicate processes that are not practically scalable.Herein we report using composition design(i.e.,enthalpy engineering)to create hierarchical,nanostructured HEAs as demonstrated by adding Ni into FeCrCoAlTi_(0.5)HEA.The strong enthalpic interaction between(Ni,Co)and(Al,Ti)pairs in FeCrCoAlTi_(0.5)Nix(x=0.5–1.5)induced phase partitions into B2(ordered phase,hard)matrix and A2(disordered phase,soft)precipitates,resulting in a hierarchical structure of B2 grains and sub-grains of near-coherent A2 nanodomains(~12.5 nm)divided by A2 interdendritic regions.As a result,the FeCrCoAlTi_(0.5)Ni_(0.5)HEA with this unique hierarchical nanostructure exhibits the best combination of strength and plasticity,i.e.,a 2-fold increase in compressive strength(2.60 GPa)and significant enhancement of plastic strain(15.8%)as compared with the original FeCrCoAlTi_(0.5)HEA.enthalpy analysis and simulation study reveal the phase partition process during cooling induced by an enthalpy-driven order-disorder transition while the order parameters illustrate the strong ordering in(Ni,Co)(Al,Ti)-rich B2 phase and high entropy mixing in less interactive FeCrCo-rich A2 phase.Our work therefore provides a strategy for hierarchical nanostructured HEA formation by composition design considering enthalpy and entropy interplay.

关键词： nanocrystalline high-entropy alloys enthalpy hierarchical structures coherent precipitates

enthalpy and entropy interaction parameters of sodium chloride with some monosaccharides in water

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Science China Chemistry 2004年第1期47卷 59-66页

作者： ZHUO Kelei, WANG Jianji, BAI Guangyue, YAN Haike & WANG HangingSchool of Chemistry and Environmental Science, Henan Normal University, Xinxiang 453002, China Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China School of Chemistry and Environmental Science Henan Normal University Xinxiang China Institute of Chemistry Chinese Academy of Sciences Beijing China Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou China

Dilution enthalpies of sodium chloride and some monosaccharides (glucose, galactose, xylose, arabinose, and fructose) in water and mixing enthalpies of aqueous sodium chloride and these monosaccharide solutions were measured by using an improved precision semimicro-titration calorimeter. Transfer enthalpies of sodium chloride from water to aqueous saccharide solutions were evaluated as well as enthalpy interaction parameters of sodium chloride with these monosaccharides in water. Combined with Gibbs energy interaction parameters, entropy interaction parameters were also obtained. The results show that interactions of the saccharides with sodium chloride depend on the stereochemistry of saccharide molecules. These interaction parameters can identify stereochemical structure of saccharide molecules.

关键词： sodium chloride, monosaccharide, enthalpy interaction parameter, entropy interaction parameter, calorimetry.

enthalpy and Exergy Transfers of High Pressure Switching Expansion Reduction

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Journal of Shanghai Jiaotong university(Science) 2012年第1期17卷 45-52页

作者：罗语溪王宣银雷军波 State Key Laboratory of Fluid Power Transmission and Control Zhejiang University

The energy balance,air internal energy,enthalpy and exergy transfers of high pressure switching expansion reduction(SER)are comparatively analyzed in this paper to give a better understanding about the exergy analysis and its difference between energy conversion analyses for the pneumatics.In SER,the exergy transfer effciency is much lower than the enthalpy effciency.The enthalpy effciency is primarily related to the initial pressure of supply tanks,and the exergy effciency is primarily related to the pressure reduction ratios.Heat transfers increase the internal energy,enthalpy and exergy of air;the influence on exergy is relatively small.The total enthalpy in SER decreases as the air temperature decreases in the expansion process of the air.And exergy loss is primarily related to the irreversible process of isenthalpic throttling but not energy conversion.Based on the analyses,to improve the exergy effciency of the pneumatics,the pressure reduction without power output should be avoided.

关键词： enthalpy exergy energy balance effciency pressure reduction

An Improved enthalpy-Based Lattice Boltzmann 3D Model with Added Probability Function for the Growth Characteristics of Frost Layer

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Journal of Thermal Science 2019年第2期28卷 378-392页

作者： CUI Jing YANG Tinghao YANG Fan YANG Guangfeng Airport College Civil Aviation University of China

In this paper, the effects of different surface properties on the growth of frost layer were numerically studied from the mesoscopic scale using the lattice Boltzmann method. The improved enthalpy method and nucleation probability model were combined to establish a three-dimensional lattice Boltzmann model based on nucleation probability theory. The model was used to carry out numerical research on frost layer formation and growth process on cold wall surface. The model could not only simulate the gradual densification and thickening process of frost layer growth from the macro scale, but also describe the change process of the frost layer structure caused by ice branch growth on the micro scale. The average thickness, average density and the amount of the frost layer could be obtained. Through this model, the temporal and spatial evolution characteristics of the topography of the frost layer were obtained. The model was used to analyze the effects of cold wall surface temperature, relative humidity and cold surface wettability on the frosting characteristics. The average thickness, frost average density, frost quality and average solid volume fraction of frost at different times were obtained by calculation.

关键词： lattice Boltzmann model improved enthalpy model nucleation probability model three-dimensional frost surface wettability

Diffusion activation enthalpy of nanocrystalline metals

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中国有色金属学会会刊：英文版 1999年第4期9卷 768-771页

作者：覃文陈振华黄培云庄应烘中南工业大学非平衡材料科学与工程所湖南长沙广西大学材料科学所广西南宁

The atomic diffusion of nanocrystalline metals showed significant difference in comparison to poycrystalline metals, this property is analyzed by considering the effect of temperature - time history on the interfacial structure. The interfacial structure is approximated by a dilated perfect crystal. Based on LeClair’s diffusi on theory, diffusbo activation enthalpy in nanocrysta1line meta1s was calculated. The results show that the change of diffusion activation enthalpy is closely related to the structure relaxation of the interfaces and the interfacial migration, the structure relaxation of the interfaces will increase the diffusion activation enthalpy when the crystallite growth can be negligible, whereas the migration of the interfaces will lead to the further increase of the diffusion activation enthalpy when crystallite growth proceeds rapid1y. The theoretical prediction is found to be in accoedance with experimental observations.

关键词： diffusion activation enthalpy structure relaxation interfacial migration

EAM APPROACH TO enthalpy OF FORMATION OF ALKALI METAL ALLOYS

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中国有色金属学会会刊：英文版 1996年第4期6卷 52-56页

作者： Zhang Bangwei Ouyang Yifang Liao Shuzhi Jin Zhanpeng1 (International Centre for Materials Physics,Shenyang 110015)2 (Department of physics,Hunan University, Changsha 410082)3 (Department of Materials Science and Engineering,Central South University of Tec International Centre for Materials Physics Shenyang 110015 China Department of Physics Hunan University Changsha 410082 China Department of Materials Science and Engineering Central South University of Technology Changsha 410083 China Department of Chemistry and Chemical Engineering Hunan University Changsha 410082 China

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关键词： EAM approach enthalpy of formation alkali metal alloys

Physical aging in Zr_(46.75)Ti_(8.25)Cu_(7.5)Ni_(10)Be_(27.5) typical bulk metallic glass manifested as enthalpy relaxation

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Science China(Physics,Mechanics & Astronomy) 2008年第4期51卷 356-364页

作者： WEN Ping,ZHAO ZuoFeng & WANG WeiHua Institute of Physics,Chinese Academy of Sciences,Beijing 100080,China Institute of Physics Chinese Academy of Sciences Beijing China

enthalpy recovery is not only an important characteristic of physical aging of glass,but also a good tool to investigate the physical aging. Using differential scanning calorimeter (DSC),the enthalpy recovery of Zr46.75Ti8.25Cu7.5Ni10Be27.5 bulk metallic glass (BMG) was studied. The typical characteristics of enthalpy recovery of glass including the sub-Tg peak and ‘overshot’ were found in BMG. The evolution of the sub-Tg peak and ‘overshot’ were described by the free volume theory and Hodge’s model,respectively. It was found that the former failed to describe the enthalpy recovery in the BMG,while the latter could give a qualitative explanation. In com-bination with the dynamics in the BMG,the origin of the enthalpy recovery in the BMG was discussed. The results show that BMGs are an ideal material to investi-gate the physical aging. The further understanding of physical aging of BMGs is useful to clarify the nature of glass and improve the application and device of new types of BMGs.

关键词： bulk metallic glass enthalpy recovery physical aging

Implementation of a One-Dimensional enthalpy Sea-Ice Model in a Simple Pycnocline Prediction Model for Sea-Ice Data Assimilation Studies

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Advances in Atmospheric Sciences 2016年第2期33卷 193-207页

作者： Xinrong WU Shaoqing ZHANG Zhengyu LIU Key Laboratory of Marine Environmental Information Technology State Oceanic AdministrationNational Marine Data and Information Service Geophysical Fluid Dynamics Laboratory National Oceanic and Atmospheric AdministrationPrinceton University Center for Climate Research and Dept.Atmospheric and Oceanic Sciences University of Wisconsin-Madison Laboratory of Ocean–Atmosphere Studies Peking University

To further explore enthalpy-based sea-ice assimilation, a one-dimensional （1D） enthalpy sea-ice model is implemented into a simple pycnocline prediction model. The 1D enthalpy sea-ice model includes the physical processes such as brine expulsion, flushing, and salt diffusion. After being coupled with the atmosphere and ocean components, the enthalpy sea-ice model can be integrated stably and serves as an important modulator of model variability. Results from a twin experiment show that the sea-ice data assimilation in the enthalpy space can produce smaller root-mean-square errors of model variables than the traditional scheme that assimilates the observations of ice concentration, especially for slow-varying states. This study provides some insights into the improvement of sea-ice data assimilation in a coupled general circulation model.

关键词： sea ice enthalpy coupled model data assimilation ensemble Kalman filter

Prediction of saturated liquid enthalpy of refrigerant mixtures

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Science China(Technological Sciences) 2007年第2期50卷 241-247页

作者： CHEN ZeShao CHEN JianXin HU Peng Department of Thermal Science&Energy Engineering University of Science and Technology of ChinaHefei 230027China

New corresponding temperature and corresponding enthalpy of refrigerant mix- tures were defined. The relationship between saturated liquid corresponding en- thalpy and corresponding temperature of refrigerant mixtures accorded with that of pure components. The characteristic parameters of saturated liquid enthalpy dif- ference of refrigerant mixtures were calculated by three methods according to the different application conditions. The generalized equation of saturated liquid en- thalpy of refrigerant mixtures was presented. The calculated values were compared with the values in literature for five ternary and binary refrigerant mixtures, namely R404A, R407A, R407B, R32/R134a, and R410A. The overall average absolute devia- tion was less than 1.0%.

关键词： refrigerant mixtures saturated liquid enthalpy prediction corresponding state