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Heat capacities measured as a function of temperature for Al115+, Al116+, and Al117+ show two well-resolved peaks, at around 450 and 600 K. After being annealed to 523 K (a temperature between the two peaks) or to 773 K (well above both peaks), the high temperature peak remains unchanged but the low temperature peak disappears. After considering the possible explanations, the low temperature peak is attributed to a structural transition and the high temperature peak to the melting of the higher enthalpy structure generated by the structural transition. The annealing results show that the liquid clusters freeze exclusively into the higher enthalpy structure and that the lower enthalpy structure is not accessible from the higher enthalpy one on the timescale of the experiments. We suggest that the low enthalpy structure observed before annealing results from epitaxy, where the smaller clusters act as a nucleus and follow a growth pattern that provides access to the low enthalpy structure. The solid-to-solid transition that leads to the low temperature peak in the heat capacity does not occur under equilibrium but requires a superheated solid. [ABSTRACT FROM AUTHOR]

Heat capacities measured as a function of temperature for Al115+, Al116+, and Al117+ show two well-resolved peaks, at around 450 and 600 K. After being annealed to 523 K (a temperature between the two peaks) or to 773 K (well above both peaks), the high temperature peak remains unchanged but the low temperature peak disappears. After considering the possible explanations, the low temperature peak is attributed to a structural transition and the high temperature peak to the melting of the higher enthalpy structure generated by the structural transition. The annealing results show that the liquid clusters freeze exclusively into the higher enthalpy structure and that the lower enthalpy structure is not accessible from the higher enthalpy one on the timescale of the experiments. We suggest that the low enthalpy structure observed before annealing results from epitaxy, where the smaller clusters act as a nucleus and follow a growth pattern that provides access to the low enthalpy structure. The solid-to-solid transition that leads to the low temperature peak in the heat capacity does not occur under equilibrium but requires a superheated solid. [ABSTRACT FROM AUTHOR]

The article discusses satellite missions like the Heat Capacity Mapping Mission (HCMM) and Global Monitoring for Environment and Security (GMES) program which perform remote sensing of land-atmosphere interface characteristics including precipitation, heat fluxes and soil moisture for climate modelling studies. According to the author, these programs provide systematic data for Earth observation science.

We study black holes in the Hořava–Lifshitz gravity with a parameter λ. For 1/3≤ λ<3, the black holes behave the Lifshitz black holes with dynamical exponent 0< z≤4, while for λ>3, the black holes behave the Reissner–Nordström type black hole in asymptotically flat spacetimes. Hence, these all are quite different from the Schwarzschild–AdS black hole of Einstein gravity. The temperature, mass, entropy, and heat capacity are derived for investigating thermodynamic properties of these black holes. [ABSTRACT FROM AUTHOR]

Abstract: The role of advanced isothermal heat storage systems in buildings is discussed. A storage system encapsulated with phase change materials in which energy is absorbed in the hot period and released in the cold period is analyzed. The thermal behaviour of isothermal heat storage composites is examined using numerical techniques. Two methods of heat transfer with latent heat storage are described in the first part. Based on the initial results, the “effective heat capacity” method was selected and implemented into ESP-r. Numerical studies on the effect of isothermal storage of solar energy in specific building material components are discussed in the second part. Numerical simulations were conducted for two cases of multi-zone, highly glazed and naturally ventilated passive solar buildings. PCM-impregnated gypsum plasterboard was used as an internal room lining in the first case study and transparent insulation material combined with PCM was applied for the external south-oriented wall in the second case study. The behaviour of a TIM–PCM wall and its influence on the internal surface temperature are estimated. Air, surface and resultant temperatures are compared with a “no-PCM” case for both case studies and the diurnal and the seasonal latent heat storage effect is analyzed. [Copyright &y& Elsevier]

Abstract: The novel technique of multi-frequency temperature modulated differential scanning calorimetry is employed to measure a decrease in the heat capacity under quasi-isothermal conditions. The effect is used to monitor the kinetics of physical aging in glassy maltitol at ∼5–8°C below the glass transition temperature. The heat capacity relaxation is analyzed by an isoconversional method that yields effective activation energy for different extents of relaxation. The early stages of aging demonstrate an activation energy ∼145kJmol−1 that is significantly smaller than the activation energy of α-relaxation (413kJmol−1), which is closely approached at the final stages of aging. [Copyright &y& Elsevier]

The gases (they consist of three or more atoms) with higher heat capacities than those of O2 and N2 cause greenhouse effect. Carbon dioxide (CO2) is main greenhouse gas associated with global climate change. Collectively, they are projected to contribute, directly, about as much too potential global warming over the next 60 years as CO2. At the present time, coal is responsible for 30–40% of world CO2 emissions from fossil fuels. There were a higher correlation between amount of carbon dioxide emission and percentage of carbon in the fuel for all equations. The squares of correlation coefficients were 0.9999, 0.9978, and 0.9995. [ABSTRACT FROM AUTHOR]

A two-temperature mathematical model of steady filtration combustion of a solid fuel in open systems is proposed. Air or a mixture of air with water vapors is considered as a gaseous oxidizer. The model takes into account that the heat capacities of the phases depend on temperature and composition and that the reactor length is finite and allows obtaining the composition of gaseous combustion products. Calculated results on gasification of a mixture of carbon with an inert component are presented. It is demonstrated that thermodynamic calculations are important for obtaining the upper estimate of gasification efficiency. Even a sufficiently long reactor becomes “short” in the regime of transient combustion waves, which results in more intense entrainment of heat by combustion products and, as a consequence, in lower efficiency of the process. [ABSTRACT FROM AUTHOR]