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Journal articles on the topic 'Enthalpy'

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Author: Grafiati

Published: 4 June 2021

Last updated: 29 July 2024

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1

Jain, Preeti, and Anil Kumar. "Enthalpic interactions in aqueous strong electrolytes upon addition of ionic liquids." Physical Chemistry Chemical Physics 20, no. 16 (2018): 11089–99. http://dx.doi.org/10.1039/c7cp07814e.

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The present study deals with the inter-ionic interactions between strong electrolytes and ionic liquids based on the thermodynamic properties such as excess partial molar enthalpy, HEIL, relative apparent molar enthalpy, ϕ_L, and the enthalpic interaction parameters.

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2

White, Kenneth. "Muybridge’s enthalpy." Public 24, no. 47 (July 1, 2013): 94–109. http://dx.doi.org/10.1386/public.24.47.94_1.

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3

Nazarov, S. A. "Surface enthalpy." Doklady Physics 53, no. 7 (July 2008): 383–87. http://dx.doi.org/10.1134/s1028335808070124.

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4

Torres, F. E., P. Kuhn, D. De Bruyker, A. G. Bell, M. V. Wolkin, E. Peeters, J. R. Williamson, et al. "Enthalpy arrays." Proceedings of the National Academy of Sciences 101, no. 26 (June 21, 2004): 9517–22. http://dx.doi.org/10.1073/pnas.0403573101.

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5

Kleykamp, Heiko. "Enthalpy, heat capacity and enthalpy of transformation of Li2TiO3." Journal of Nuclear Materials 295, no. 2-3 (June 2001): 244–48. http://dx.doi.org/10.1016/s0022-3115(01)00550-5.

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6

Giraldo, Liliana, and Juan Carlos Moreno-Piraján. "Enthalpic Contribution of Ni(II) in the Interaction between Carbonaceous Material and Aqueous Solution." Journal of Chemistry 2017 (2017): 1–7. http://dx.doi.org/10.1155/2017/7308024.

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Solid adsorbents were prepared from corn cob that was modified with a solution of HNO3 6 M at different contact times. The solids are characterized by physical N2 adsorption at 77 K to know their surface area by applying the BET model and surface chemistry is determined using the Bohem method. Once we have prepared the adsorbents we determine the immersion enthalpy, ΔHim, of the solids in Ni(II) aqueous solutions of different concentrations between 20 and 800 mg·L−1, with values for ΔHim between 10.0 and 35.3 J·g−1. From the results obtained for the immersion enthalpy in function of the ion Ni(II) concentration we calculate the contribution to the immersion enthalpy that corresponds to the ion when it is treated with the system adsorbent-solution as a mixture in which the solid, the solvent, and the adsorbate are involved. The solution thermodynamics allows for establishing the enthalpic changes that bring the ion in function of the concentration and the intensity of the interaction of solid-metal ion that is favored by the presence of acid groups in the solid.

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7

Pinheiro, Bruno D. A., Ana R. R. P. Almeida, and Manuel J. S. Monte. "Phase transitions properties of N,N-dimethyl-4-nitroaniline." U.Porto Journal of Engineering 9, no. 5 (November 24, 2023): 77–88. http://dx.doi.org/10.24840/2183-6493_009-005_002176.

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The present work reports an experimental study aiming to determine several thermodynamic properties of fusion and sublimation of the chromophore N,N-dimethyl-4-nitroaniline. This compound is commonly used as a reference in studies focused on the non-linear optical (NLO) characteristics of chromophores. Using the Knudsen mass-loss effusion method, the vapor pressures of the crystalline phase of N,N-dimethyl-4-nitroaniline were measured over the temperature range between 341.1 K and 363.5 K. The standard molar enthalpy, entropy, and Gibbs energy of sublimation were calculated from the experimental results, at 298.15 K, and compared with those given in the literature. Differential scanning calorimetry was used to determine the temperature and enthalpy of fusion, as well as the isobaric heat capacities of the crystalline compound under study. Additionally, the enthalpic and entropic contributions to N,N-dimethyl-4-nitroaniline’s volatility were assessed, and it was determined that is greatly conditioned by enthalpic factors.

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8

DeTar, DeLos F., Seyhun Binzet, and Prashanth Darba. "Formal steric enthalpy." Journal of Organic Chemistry 50, no. 16 (August 1985): 2826–36. http://dx.doi.org/10.1021/jo00216a004.

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9

Zhao Tai-Ze, Wang Fei, Guo Shao-Feng, Guo Wen-Kang, and Xu Ping. "Rapid enthalpy probe." Acta Physica Sinica 56, no. 10 (2007): 5952. http://dx.doi.org/10.7498/aps.56.5952.

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10

Nilsson, Tor, and Hans Niedderer. "Undergraduate students' conceptions of enthalpy, enthalpy change and related concepts." Chem. Educ. Res. Pract. 15, no. 3 (2014): 336–53. http://dx.doi.org/10.1039/c2rp20135f.

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11

Wormald, C. J., and T. K. Yerlett. "A new enthalpy-increment calorimeter enthalpy increments for n-hexane." Journal of Chemical Thermodynamics 17, no. 12 (December 1985): 1171–86. http://dx.doi.org/10.1016/0021-9614(85)90044-8.

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12

Ledo, Juan M., Henoc Flores, Fernando Ramos, and Elsa A. Camarillo. "Thermochemical Study of 1-Methylhydantoin." Molecules 27, no. 2 (January 16, 2022): 556. http://dx.doi.org/10.3390/molecules27020556.

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Using static bomb combustion calorimetry, the combustion energy of 1-methylhydantoin was obtained, from which the standard molar enthalpy of formation of the crystalline phase at T = 298.15 K of the compound studied was calculated. Through thermogravimetry, mass loss rates were measured as a function of temperature, from which the enthalpy of vaporization was calculated. Additionally, some properties of fusion were determined by differential scanning calorimetry, such as enthalpy and temperature. Adding the enthalpy of fusion to the enthalpy of vaporization, the enthalpy of sublimation of the compound was obtained at T = 298.15 K. By combining the enthalpy of formation of the compound in crystalline phase with its enthalpy of sublimation, the respective standard molar enthalpy of formation in the gas phase was calculated. On the other hand, the results obtained in the present work were compared with those of other derivatives of hydantoin, with which the effect of the change of some substituents in the base heterocyclic ring was evaluated.

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13

Duan, L., and M. P. Martín. "Direct numerical simulation of hypersonic turbulent boundary layers. Part 4. Effect of high enthalpy." Journal of Fluid Mechanics 684 (September 6, 2011): 25–59. http://dx.doi.org/10.1017/jfm.2011.252.

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AbstractIn this paper we present direct numerical simulations (DNS) of hypersonic turbulent boundary layers to study high-enthalpy effects. We study high- and low-enthalpy conditions, which are representative of those in hypersonic flight and ground-based facilities, respectively. We find that high-enthalpy boundary layers closely resemble those at low enthalpy. Many of the scaling relations for low-enthalpy flows, such as van-Driest transformation for the mean velocity, Morkovin’s scaling and the modified strong Reynolds analogy hold or can be generalized for high-enthalpy flows by removing the calorically perfect-gas assumption. We propose a generalized form of the modified Crocco relation, which relates the mean temperature and mean velocity across a wide range of conditions, including non-adiabatic cold walls and real gas effects. The DNS data predict Reynolds analogy factors in the range of those found in experimental data at low-enthalpy conditions. The gradient transport model approximately holds with turbulent Prandtl number and turbulent Schmidt number of order unity. Direct compressibility effects remain small and insignificant for all enthalpy cases. High-enthalpy effects have no sizable influence on turbulent kinetic energy (TKE) budgets or on the turbulence structure.

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14

Mazeina, Lena, Suraj Deore, and Alexandra Navrotsky. "Energetics of Bulk and Nano-Akaganeite, β-FeOOH: Enthalpy of Formation, Surface Enthalpy, and Enthalpy of Water Adsorption." Chemistry of Materials 18, no. 7 (April 2006): 1830–38. http://dx.doi.org/10.1021/cm052543j.

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15

Liu, Xiaochen, Xiaohua Liu, Tao Zhang, and Ying Xie. "Experimental analysis and performance optimization of a counter-flow enthalpy recovery device using liquid desiccant." Building Services Engineering Research and Technology 39, no. 6 (May 30, 2018): 679–97. http://dx.doi.org/10.1177/0143624418780852.

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The liquid desiccant enthalpy recovery is an efficient way to save energy in air-conditioning systems. In this study, a counter-flow liquid desiccant enthalpy recovery device was proposed and experimentally analyzed. Enthalpy transfer capacity, enthalpy efficiency and pressure drop per height of packing were used as indices to describe its performances. Based on the experiment results, the heat and mass transfer model of a packed tower was used to simulate and optimize the performance of this device. The maximum enthalpy efficiency and enthalpy transfer capacity were achieved when the optimal air velocity (1.9–2.1 m/s in this study) maintained to be slightly below the air velocity at the loading point and the thermal capacity ratio of air to desiccant ( m*) equaled to 1. These conclusions are valuable to both design and operation of such an enthalpy recovery device. Practical application: A counter-flow enthalpy recovery device with liquid desiccant was proposed and experimentally investigated. Based on the experiment results, a numerical model for this device was built and validated. The optimal air and desiccant mass fluxes were analyzed to maximize the enthalpy efficiency of this device, which could be higher than the conventional device with cross-flow pattern. These results could provide guidelines for both design and operation management of counter-flow enthalpy recovery devices in liquid desiccant-based air-conditioning systems.

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16

Runjun, Huang, Huang Zengwei, Song Baoling, Liao Sen, Wei Dongping, and Yuan Aiqun. "Standard Molar Formation Enthalpy of NH4Zn2PO4HPO4and Its Standard Molar Formation Enthalpy." Integrated Ferroelectrics 162, no. 1 (May 4, 2015): 46–54. http://dx.doi.org/10.1080/10584587.2015.1038133.

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17

Papina, T. S., V. P. Kolesov, V. A. Lukyanova, O. V. Boltalina, A. Yu Lukonin, and L. N. Sidorov. "Enthalpy of Formation and C−F Bond Enthalpy of Fluorofullerene C60F36." Journal of Physical Chemistry B 104, no. 23 (June 2000): 5403–5. http://dx.doi.org/10.1021/jp000409a.

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18

Majzlan, Juraj, Lena Mazeina, and Alexandra Navrotsky. "Enthalpy of water adsorption and surface enthalpy of lepidocrocite (γ-FeOOH)." Geochimica et Cosmochimica Acta 71, no. 3 (February 2007): 615–23. http://dx.doi.org/10.1016/j.gca.2006.10.010.

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19

Pinto, Isabel, Helena Cardoso, Cecélia Leão, and N. van Uden. "High enthalpy and low enthalpy death inSaccharomyces cerevisiaeinduced by acetic acid." Biotechnology and Bioengineering 33, no. 10 (April 20, 1989): 1350–52. http://dx.doi.org/10.1002/bit.260331019.

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20

Zhang, Yi, Dong Ming Guo, and Da Liu. "Utilization and Research on Medium-Enthalpy and Low-Enthalpy Geothermal Energy in WSHP System." Advanced Materials Research 374-377 (October 2011): 392–97. http://dx.doi.org/10.4028/www.scientific.net/amr.374-377.392.

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Geothermal energy is a stable energy, stored underground and not influenced by the geographical, seasonal weather and the change of day and night. Medium-enthalpy and low-enthalpy geothermal energy are distributed in many areas of China, having a broad prospect for development. Taking water resources heat pump (WSHP) engineering in Tianqiao District as an example, medium-enthalpy and low-enthalpy geothermal energy is combined with the technology of aquifer thermal energy storage (ATES), providing cold energy in summer and warm energy in winter for the buildings. On the base of analysis of hydrogeological conditions in Tianqiao District, the temperature field of energy storage aquifers is numerically analyzed in the period of heating and cooling. The results show that the energy storage well can meet the requirement of heating and cooling conditions. The system of WSHP greatly utilizes medium-enthalpy and low-enthalpy geothermal energy, making the running costs economical.

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21

Murthy, Varun S., and William R. Boos. "Role of Surface Enthalpy Fluxes in Idealized Simulations of Tropical Depression Spinup." Journal of the Atmospheric Sciences 75, no. 6 (May 17, 2018): 1811–31. http://dx.doi.org/10.1175/jas-d-17-0119.1.

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AbstractAn idealized, three-dimensional, cloud-system-resolving model is used to investigate the influence of surface enthalpy flux variations on tropical depression (TD) spinup, an early stage of tropical cyclogenesis in which the role of surface fluxes remains incompletely understood. A range of simulations supports the hypothesis that a negative radial gradient of surface enthalpy flux outside the storm center is necessary for TD spinup but can arise from multiple mechanisms. The negative radial gradient is typically created by the wind speed dependence of surface enthalpy fluxes, consistent with some previous theories for tropical cyclone intensification. However, when surface enthalpy fluxes are prescribed to be independent of wind speed, spinup still occurs, albeit more slowly, with the negative radial gradient of surface enthalpy flux maintained by an enhanced air–sea thermodynamic disequilibrium beneath the cold core of the incipient vortex. Surface enthalpy flux variations seem more important for intensification than initial conditions. For example, a vortex forms and intensifies even from a state of rest when the center of the domain is initialized to be nearly saturated with water vapor, but this intensification is modest in amplitude and transient, lasting less than 12 h, without interactive surface enthalpy flux. Sustained spinup on time scales longer than a day does not occur when surface enthalpy fluxes are horizontally homogeneous or constant, even when fixed at the high value of 200 W m−2. In the ensemble of simulations presented here, the vortex intensification rate scales linearly with the storm-scale surface enthalpy flux anomaly relative to the undisturbed environment.

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22

Majzlan, Juraj. "Surface Enthalpy of Boehmite." Clays and Clay Minerals 48, no. 6 (2000): 699–707. http://dx.doi.org/10.1346/ccmn.2000.0480611.

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23

Mulero, A., and I. Cachadiña. "Boiling enthalpy from correlations." Thermochimica Acta 443, no. 1 (April 2006): 37–48. http://dx.doi.org/10.1016/j.tca.2005.12.018.

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24

Head-Gordon, Teresa, and Frank H. Stillinger. "Enthalpy of knotted polypeptides." Journal of Physical Chemistry 96, no. 19 (September 1992): 7792–96. http://dx.doi.org/10.1021/j100198a054.

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25

Van Ness, Hendrick C. "H Is for Enthalpy." Journal of Chemical Education 80, no. 5 (May 2003): 486. http://dx.doi.org/10.1021/ed080p486.1.

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26

Vine, M. D., and C. J. Wormald. "The enthalpy of benzene." Journal of Chemical Thermodynamics 23, no. 12 (December 1991): 1175–80. http://dx.doi.org/10.1016/s0021-9614(05)80151-x.

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27

Watson, Christopher B., Dustin Tan, and David E. Bergbreiter. "Enthalpy-Driven Polyisobutylene Depolymerization." Macromolecules 52, no. 8 (April 9, 2019): 3042–48. http://dx.doi.org/10.1021/acs.macromol.9b00313.

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28

Yerlett, T. K., and C. J. Wormald. "The enthalpy of acetone." Journal of Chemical Thermodynamics 18, no. 4 (April 1986): 371–79. http://dx.doi.org/10.1016/0021-9614(86)90083-2.

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29

Yerlett, T. K., and C. J. Wormald. "The enthalpy of methanol." Journal of Chemical Thermodynamics 18, no. 8 (August 1986): 719–26. http://dx.doi.org/10.1016/0021-9614(86)90105-9.

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30

Vine, M. D., and C. J. Wormald. "The enthalpy of ethanol." Journal of Chemical Thermodynamics 21, no. 11 (November 1989): 1151–57. http://dx.doi.org/10.1016/0021-9614(89)90101-8.

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31

Ivanova, N., and S. Chaichenets. "COMMON ENVELOPE: ENTHALPY CONSIDERATION." Astrophysical Journal 731, no. 2 (March 30, 2011): L36. http://dx.doi.org/10.1088/2041-8205/731/2/l36.

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32

Mazeina, Lena, and Alexandra Navrotsky. "Surface enthalpy of goethite." clays and clay minerals 53, no. 2 (April 1, 2005): 113–22. http://dx.doi.org/10.1346/ccmn.2005.0530201.

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33

Wiegand, Fred J. "ENTHALPY OF SUPERHEATED STEAM." Journal of the American Society for Naval Engineers 51, no. 1 (March 18, 2009): 99–100. http://dx.doi.org/10.1111/j.1559-3584.1939.tb01455.x.

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34

Murdock., James W. "ENTHALPY OF SUPERHEATED STEAM." Journal of the American Society for Naval Engineers 54, no. 3 (March 18, 2009): 370–71. http://dx.doi.org/10.1111/j.1559-3584.1942.tb02103.x.

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35

SWAMINATHAN, C. R., and V. R. VOLLER. "ON THE ENTHALPY METHOD." International Journal of Numerical Methods for Heat & Fluid Flow 3, no. 3 (March 1993): 233–44. http://dx.doi.org/10.1108/eb017528.

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36

Poland, Douglas. "Enthalpy distributions in proteins." Biopolymers 58, no. 1 (2000): 89–105. http://dx.doi.org/10.1002/1097-0282(200101)58:1<89::aid-bip90>3.0.co;2-7.

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37

Ribeiro da Silva, Manuel A. V., Ana M. M. V. Reis, Manuel J. S. Monte, Madalena M. S. S. F. Bártolo, and João A. R. G. O. Rodrigues. "Enthalpy of combustion, vapour pressures, and enthalpy of sublimation of 3-nitrophenol." Journal of Chemical Thermodynamics 24, no. 6 (June 1992): 653–59. http://dx.doi.org/10.1016/s0021-9614(05)80037-0.

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38

Mazeina, Lena, Sergey V. Ushakov, Alexandra Navrotsky, and Lynn A. Boatner. "Formation enthalpy of ThSiO4 and enthalpy of the thorite → huttonite phase transition." Geochimica et Cosmochimica Acta 69, no. 19 (October 2005): 4675–83. http://dx.doi.org/10.1016/j.gca.2005.03.053.

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39

Pimenova, Svetlana M., Svetlana V. Melkhanova, Victor P. Kolesov, and Anatolii S. Lobach. "The Enthalpy of Formation and C−H Bond Enthalpy of Hydrofullerene C60H36." Journal of Physical Chemistry B 106, no. 9 (March 2002): 2127–30. http://dx.doi.org/10.1021/jp012258x.

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40

Cherifa, A. Ben, M. Jemal, A. Nounah, and J. L. Lacout. "Enthalpy of formation and enthalpy of mixing of calcium and cadmium hydroxyapatites." Thermochimica Acta 237, no. 2 (June 1994): 285–93. http://dx.doi.org/10.1016/0040-6031(94)80186-x.

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41

Hong, Beichuan, Varun Venkataraman, and Andreas Cronhjort. "Numerical Analysis of Engine Exhaust Flow Parameters for Resolving Pre-Turbine Pulsating Flow Enthalpy and Exergy." Energies 14, no. 19 (September 28, 2021): 6183. http://dx.doi.org/10.3390/en14196183.

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Energy carried by engine exhaust pulses is critical to the performance of a turbine or any other exhaust energy recovery system. Enthalpy and exergy are commonly used concepts to describe the energy transport by the flow based on the first and second laws of thermodynamics. However, in order to investigate the crank-angle-resolved exhaust flow enthalpy and exergy, the significance of the flow parameters (pressure, velocity, and temperature) and their demand for high resolution need to be ascertained. In this study, local and global sensitivity analyses were performed on a one-dimensional (1D) heavy-duty diesel engine model to quantify the significance of each flow parameter in the determination of exhaust enthalpy and exergy. The effects of parameter sweeps were analyzed by local sensitivity, and Sobol indices from the global sensitivity showed the correlations between each flow parameter and the computed enthalpy and exergy. The analysis indicated that when considering the specific enthalpy and exergy, flow temperature is the dominant parameter and requires high resolution of the temperature pulse. It was found that a 5% sweep over the temperature pulse leads to maximum deviations of 31% and 27% when resolving the crank angle-based specific enthalpy and specific exergy, respectively. However, when considering the total enthalpy and exergy rates, flow velocity is the most significant parameter, requiring high resolution with a maximum deviation of 23% for the enthalpy rate and 12% for the exergy rate over a 5% sweep of the flow velocity pulse. This study will help to quantify and prioritize fast measurements of pulsating flow parameters in the context of turbocharger turbine inlet flow enthalpy and exergy analysis.

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42

Gurov, A. A., S. V. Kozhevnikova, A. N. Ozhogina, and S. N. Solovyev. "Nickel Sulfate Aqueous Solutions Thermal Chemistry and Enthalpy of Ni2+ Cation Formation at the Temperature 298.15 K." Herald of the Bauman Moscow State Technical University. Series Natural Sciences, no. 1 (88) (February 2020): 93–99. http://dx.doi.org/10.18698/1812-3368-2020-1-93-99.

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Calorimeter with an isothermal shell was used at a temperature of 298.15 K to measure the following parameters: enthalpy of NiSO4(k) dissolution in water followed by generation of two molar concentration solutions; enthalpy of four NiSO4 aqueous solutions dilution having various molar concentrations followed by generation of solutions with approximately the same concentration values. Based on the data obtained, enthalpy and ion association constant in the NiSO4 aqueous solution, as well as standard enthalpy of the aqueous solution formation, were determined for the indicated compound. The latter value made it possible to establish a more accurate value of standard enthalpy in the Ni2+ cation formation in an aqueous solution, which turned out to be equal to --52.3 ± 0.5 kJ/mol.

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43

Suraya Md Nasrudin, Farah, and Shafaruniza Mahadi. "Enthalpy method for one dimensional heat conduction." International Journal of Engineering & Technology 7, no. 2.14 (April 6, 2018): 9. http://dx.doi.org/10.14419/ijet.v7i2.14.11143.

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In this paper, the Enthalpy Method is employed to compute an approximate solution of the system of nonlinear differential equations focusing on the simulation of moving boundary for one dimensional heat conduction. This paper is only considered in the problem of a technical grade paraffin’s melting process. In order to seek the solution in term of temperature distribution, Finite Difference Method will be used. The results obtained are compared between solving with enthalpy and without enthalpy. The enthalpy method is more versatile, convenient, adaptable and easily programmable.

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44

Benn, D. I., A. C. Fowler, I. Hewitt, and H. Sevestre. "A general theory of glacier surges." Journal of Glaciology 65, no. 253 (August 29, 2019): 701–16. http://dx.doi.org/10.1017/jog.2019.62.

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AbstractWe present the first general theory of glacier surging that includes both temperate and polythermal glacier surges, based on coupled mass and enthalpy budgets. Enthalpy (in the form of thermal energy and water) is gained at the glacier bed from geothermal heating plus frictional heating (expenditure of potential energy) as a consequence of ice flow. Enthalpy losses occur by conduction and loss of meltwater from the system. Because enthalpy directly impacts flow speeds, mass and enthalpy budgets must simultaneously balance if a glacier is to maintain a steady flow. If not, glaciers undergo out-of-phase mass and enthalpy cycles, manifest as quiescent and surge phases. We illustrate the theory using a lumped element model, which parameterizes key thermodynamic and hydrological processes, including surface-to-bed drainage and distributed and channelized drainage systems. Model output exhibits many of the observed characteristics of polythermal and temperate glacier surges, including the association of surging behaviour with particular combinations of climate (precipitation, temperature), geometry (length, slope) and bed properties (hydraulic conductivity). Enthalpy balance theory explains a broad spectrum of observed surging behaviour in a single framework, and offers an answer to the wider question of why the majority of glaciers do not surge.

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45

Michael Ioelovich. "Application of thermochemical methods for the study of cellulose and cellulose esters." World Journal of Advanced Research and Reviews 18, no. 3 (June 30, 2023): 1477–88. http://dx.doi.org/10.30574/wjarr.2023.18.3.1260.

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In this research, the enthalpy of the interaction of cellulose and cellulose esters with various polar liquids was studied. Besides, the standard enthalpies of combustion and formation of cellulose and its esters were determined. It was shown that the absolute value of the standard exothermic enthalpy of the interaction of cellulose with the polar liquids is an indicator of the accessibility of the supramolecular structure for these liquids. It has been also established that the interaction enthalpy of cellulose materials with water, i.e., wetting enthalpy, is directly proportional to the content of non-crystalline domains and inversely proportional to the degree of cellulose crystallinity. In the case of cellulose esters, the wetting enthalpy characterizes their substitution degree and hydrophobicity, which are the higher, the lower the absolute value of the exothermic wetting enthalpy. The determination of the standard enthalpies of combustion and formation of cellulose and the melting heats of crystallites was carried out to evaluate the relative thermodynamic stability of CI, CII, CIII, and CIV crystalline forms and amorphous cellulose. For esters of cellulose, it was shown that an increase in the degree of substitution contributes to enhancing the exothermic enthalpy of the formation; thus, the esterification of cellulose is thermodynamically favorable.

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46

Jeong, Dahai, Brian K. Haus, and Mark A. Donelan. "Enthalpy Transfer across the Air–Water Interface in High Winds Including Spray." Journal of the Atmospheric Sciences 69, no. 9 (September 1, 2012): 2733–48. http://dx.doi.org/10.1175/jas-d-11-0260.1.

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Abstract Controlled experiments were conducted in the Air–Sea Interaction Saltwater Tank (ASIST) at the University of Miami to investigate air–sea moist enthalpy transfer rates under various wind speeds (range of 0.6–39 m s−1 scaled to equivalent 10-m neutral winds) and water–air temperature differences (range of 1.3°–9.2°C). An indirect calorimetric (heat content budget) measurement technique yielded accurate determinations of moist enthalpy flux over the full range of wind speeds. These winds included conditions with significant spray generation, the concentrations of which were of the same order as field observations. The moist enthalpy exchange coefficient so measured included a contribution from cooled reentrant spray and therefore serves as an upper limit for the interfacial transfer of enthalpy. An unknown quantity of spray was also observed to exit the tank without evaporating. By invoking an air volume enthalpy budget it was determined that the potential contribution of this exiting spray over an unbounded water volume was up to 28%. These two limits bound the total enthalpy transfer coefficient including spray-mediated transfers.

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Yagofarov, Mikhail I., Ilya S. Balakhontsev, Andrey A. Sokolov, and Boris N. Solomonov. "Application of Solution Calorimetry to Determining the Fusion Enthalpy of an Arylaliphatic Compound at 298.15 K: n-Octadecanophenone." Liquids 3, no. 1 (December 21, 2022): 1–6. http://dx.doi.org/10.3390/liquids3010001.

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Abstract:

Evaluating the temperature dependence of the fusion enthalpy is no trivial task, as any compound melts at a unique temperature. At the same time, knowledge of the fusion enthalpies under some common conditions, particularly at the reference temperature of 298.15 K, would substantially facilitate the comparative analysis and development of the predictive schemes. In this work, we continue our investigations of the temperature dependence of the fusion enthalpy of organic non-electrolytes using solution calorimetry. As an object of study, n-octadecanophenone, an arylaliphatic compound was chosen. The solvent appropriate for evaluating the fusion enthalpy at 298.15 K from the solution enthalpy of crystal was selected: p-xylene. The heat capacity and fusion enthalpy at the melting temperature were measured by differential scanning calorimetry to derive the fusion enthalpy at 298.15 K from the Kirchhoff’s law of Thermochemistry. An agreement between the independently determined values was demonstrated. This particular result opens a perspective for further studies of the fusion thermochemistry of arylaliphatic compounds at 298.15 K by solution calorimetry.

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48

Stolyarova, T. A., E. G. Osadchii, and A. V. Baranov. "Standard enthalpy of formation kesterite Cu2ZnSnS4." Геохимия 64, no. 1 (January 15, 2019): 101–4. http://dx.doi.org/10.31857/s0016-7525641101-104.

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The standard enthalpy of kesterite formation (Cu2ZnSnS4) is calculated from the calorimetric determinations of the enthalpy of its formation from simple sulphides: 2CuS + ZnS + SnS → Cu2ZnSnS4 using literature data on the standard enthalpies of the formation of simple sulphides. As a result, the standard enthalpy of kesterite formation was determined: ΔfHo298.15 (Cu2ZnSnS4) = -(467.62±2.28) kJ mol-1.

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Liu, Sha, Pei Hong Wang, and Zhi Gang Su. "The Exhaust Steam Enthalpy of Steam Turbine Cognitive Modeling Based on Simplify Evidential Regression Multi-Model." Advanced Materials Research 614-615 (December 2012): 83–88. http://dx.doi.org/10.4028/www.scientific.net/amr.614-615.83.

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The calculation of exhaust steam enthalpy for steam turbine units is an important parameter in the on-line monitoring and system analysis for thermal power plants. The cognitive modeling method for exhaust steam enthalpy based on evidence theory was studied in this paper. Take 330MW steam turbine for example, exhaust steam enthalpy samples are obtained from steam turbine variable condition analysis model, then exhaust steam enthalpy cognitive model based on simplify evidential regression multi-model is established. The error analysis shows that the accuracy of this model has higher prediction accuracy than the SVM and NW soft measurement model.

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50

Li, Yuanyuan, Tongrui Cheng, Zhenning Zhao, and Liangcai Xu. "Compare the Calculations of Steam Extraction Efficiency of Power Plant Turbine by Simple Heat Balance Method and Equivalent Enthalpy Drop Method." E3S Web of Conferences 204 (2020): 02011. http://dx.doi.org/10.1051/e3sconf/202020402011.

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At present, the calculation method of steam extraction efficiency of power plant turbine have five methods: heat balance method, equivalent enthalpy drop method, cyclicfunctional method, composite structure method and matrix method. In this paper, a 600MW grade subcritical thermal power plan is take as an examplefor comparing the calculation by the simple heat balance method and the equivalent enthalpy drop method. The result shows that the computational results of simple heat balance method agree with equivalent enthalpy drop method. So simple heat balance method can be used to replace equivalent enthalpy drop method in order to reduce calculation amount in practicalapplication.

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