Journal articles: 'Quasi-equilibrium temperature'

1

Netrebko, Aleksej, and Olga Chichigina. "Quasi-equilibrium Boltzmann distribution." Izvestiya VUZ. Applied Nonlinear Dynamics 9, no. 3 (2001): 85–95. http://dx.doi.org/10.18500/0869-6632-2001-9-3-85-95.

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Stationary coordinate distribution is received for nonequilibrium states of system, which lifetime is much more than correlations time. It is shown, that this weak nonequilibrium is revealed by decrease of effective temperature. Results are confirmed by computer simulations. The way of potential energy coordinate dependence determination by means of lifetime’s temperature dependence is proposed.

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Nishida, Koji, Mari Saiga, Yudai Fujishima, Hiroki Ogawa, and Toshiji Kanaya. "Quasi-Equilibrium Gelation Temperature of Aqueous Methylcellulose." Journal of Fiber Science and Technology 72, no. 12 (2016): 251–57. http://dx.doi.org/10.2115/fiberst.fiberst.2016-0037.

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Gerasimov, Alexander, and Alexander Kirpichnikov. "Quasi-equilibrium channel model of an constant current arc." Thermal Science 7, no. 1 (2003): 101–8. http://dx.doi.org/10.2298/tsci0301101g.

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The rather simple method of calculation of electronic and gas temperature in the channel of arc of plasma generator is offered. This method is based on self-consistent two-temperature channel model of an electric arc. The method proposed enables to obtain radial allocation of gas and electronic temperatures in a non-conducting zone of an constant current arc, for prescribed parameters of discharge (current intensity and power of the discharge), with enough good precision. The results obtained can be used in model and engineering calculations to estimate gas and electronic temperatures in the channel of an arc plasma generator.

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Holloway, Christopher E., and J. David Neelin. "The Convective Cold Top and Quasi Equilibrium*." Journal of the Atmospheric Sciences 64, no. 5 (2007): 1467–87. http://dx.doi.org/10.1175/jas3907.1.

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Abstract To investigate dominant vertical structures of observed temperature perturbations, and to test the temperature implications of the convective quasi-equilibrium hypothesis, the relationship of the tropical temperature profile to the average free-tropospheric temperature is examined in Atmospheric Infrared Sounder (AIRS) satellite data, radiosonde observations, and National Centers for Environmental Prediction–National Center for Atmospheric Research (NCEP–NCAR) reanalysis. The spatial scales analyzed extend from the entire Tropics down to a single reanalysis grid point or radiosonde station, with monthly to daily time scales. There is very high vertical coherence of free-tropospheric temperature perturbations. There is also fairly good agreement throughout the free troposphere between observations and a theoretical quasi-equilibrium perturbation profile calculated from a distribution of moist adiabats. The boundary layer is fairly independent from the free troposphere, especially for smaller scales. A third vertical feature of the temperature perturbation profile is here termed the “convective cold top”—a robust negative correlation between temperature perturbations of the vertically averaged free troposphere and those of the upper troposphere and lower stratosphere. The convective cold top is found for observations and reanalysis at many temporal and spatial scales. Given this prevalence, the literature is reviewed for previous examples of what is likely a single phenomenon. One simple explanation is proposed: hydrostatic pressure gradients from tropospheric warming extend above the heating, forcing ascent and adiabatic cooling. The negative temperature anomalies thus created are necessary for anomalous pressure gradients to diminish with height.

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Zhang, Jianhua, Wen Zheng, Shiyun Zhang, et al. "Unifying fluctuation-dissipation temperatures of slow-evolving nonequilibrium systems from the perspective of inherent structures." Science Advances 7, no. 31 (2021): eabg6766. http://dx.doi.org/10.1126/sciadv.abg6766.

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For nonequilibrium systems, how to define temperature is one of the key and difficult issues to solve. Although effective temperatures have been proposed and studied to this end, it still remains elusive what they actually are. Here, we focus on the fluctuation-dissipation temperatures and report that such effective temperatures of slow-evolving systems represent characteristic temperatures of their equilibrium counterparts. By calculating the fluctuation-dissipation relation of inherent structures, we obtain a temperature-like quantity TIS. For monocomponent crystal-formers, TIS agrees well with the crystallization temperature Tc, while it matches with the onset temperature Ton for glass-formers. It also agrees with effective temperatures of typical nonequilibrium systems, such as aging glasses, quasi-static shear flows, and quasi-static self-propelled flows. From the unique perspective of inherent structures, our study reveals the nature of effective temperatures and the underlying connections between nonequilibrium and equilibrium systems and confirms the equivalence between Ton and Tc.

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Nie, Ji, William R. Boos, and Zhiming Kuang. "Observational Evaluation of a Convective Quasi-Equilibrium View of Monsoons." Journal of Climate 23, no. 16 (2010): 4416–28. http://dx.doi.org/10.1175/2010jcli3505.1.

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Abstract Idealized dynamical theories that employ a convective quasi-equilibrium (QE) treatment for the diabatic effects of moist convection have been used to explain the location, intensity, and intraseasonal evolution of monsoons. This paper examines whether observations of the earth’s regional monsoons are consistent with the assumption of QE. It is shown here that in local summer climatologies based on reanalysis data, maxima of free-tropospheric temperature are, indeed, nearly collocated with maxima of subcloud equivalent potential temperature, θeb, in all monsoon regions except the North and South American monsoons. Free-tropospheric temperatures over North Africa also exhibit a strong remote influence from the South Asian monsoon. Consistent with idealized dynamical theories, peak precipitation falls slightly equatorward of the maxima in θeb and free-tropospheric temperature in regions where QE seems to hold. Vertical structures of temperature and wind reveal two types of monsoon circulations. One is the deep, moist baroclinic circulation clearly seen in the South Asian monsoon. The other is of mixed type, with the deep moist circulation superimposed on a shallow dry circulation closely associated with boundary layer temperature gradients. While the existence of a shallow dry circulation has been documented extensively in the North African monsoon, here it is shown to also exist in Australia and southern Africa during the local summer. Analogous to moist QE theories for the deep circulation, the shallow circulation can be viewed in a dry QE framework in which shallow ascent occurs just equatorward of the peak boundary layer potential temperature, θb, providing a unified system where the poleward extents of deep and shallow circulations are bounded by maxima in θeb and θb, respectively.

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Nomoto, Sukeharu, Masahito Segawa, and Makoto Watanabe. "Non- and Quasi-Equilibrium Multi-Phase Field Methods Coupled with CALPHAD Database for Rapid-Solidification Microstructural Evolution in Laser Powder Bed Additive Manufacturing Condition." Metals 11, no. 4 (2021): 626. http://dx.doi.org/10.3390/met11040626.

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A solidification microstructure is formed under high cooling rates and temperature gradients in powder-based additive manufacturing. In this study, a non-equilibrium multi-phase field method (MPFM), based on a finite interface dissipation model, coupled with the Calculation of Phase Diagram (CALPHAD) database, was developed for a multicomponent Ni alloy. A quasi-equilibrium MPFM was also developed for comparison. Two-dimensional equiaxed microstructural evolution for the Ni (Bal.)-Al-Co-Cr-Mo-Ta-Ti-W-C alloy was performed at various cooling rates. The temperature-γ fraction profiles obtained under 105 K/s using non- and quasi-equilibrium MPFMs were in good agreement with each other. Over 106 K/s, the differences between the non- and quasi-equilibrium methods grew as the cooling rate increased. The non-equilibrium solidification was strengthened over a cooling rate of 106 K/s. Columnar-solidification microstructural evolution was performed at cooling rates of 5 × 105 K/s to 1 × 107 K/s at various temperature gradient values under a constant interface velocity (0.1 m/s). The results show that, as the cooling rate increased, the cell space decreased in both methods, and the non-equilibrium MPFM was verified by comparing with the quasi-equilibrium MPFM. Our results show that the non-equilibrium MPFM showed the ability to simulate the solidification microstructure in powder bed fusion additive manufacturing.

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Gonzalez-Vallejo, I., V. L. R. Jacques, D. Boschetto, et al. "Time-resolved structural dynamics of the out-of-equilibrium charge density wave phase transition in GdTe₃." Structural Dynamics 9, no. 1 (2022): 014502. http://dx.doi.org/10.1063/4.0000131.

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We use ultrafast electron diffraction to study the out-of-equilibrium dynamics of the charge density wave (CDW) phase transition in GdTe3, a quasi-two-dimensional compound displaying a unidirectional CDW state. Experiments were conducted at different incident fluences and different initial sample temperatures below T c. We find that following photo-excitation, the system undergoes a non-thermal ultrafast phase transition that occurs in out-of-equilibrium conditions. The intrinsic crystal temperature was estimated at each time delay from the atomic thermal motion, which affects each Bragg peak intensity via the Debye Waller factor. We find that the crystal temperature stabilizes with a 6 ps timescale in a quasi-equilibrium state at temperature [Formula: see text]. We then relate the recovery time of the CDW and its correlation lengths as a function of [Formula: see text]. The charge density wave is suppressed in less than a picosecond while its recovery time increases linearly with incident fluence and initial temperature. Our results highlight that the dynamics is strongly determined by the initial sample temperature. In addition, the transient CDW phase recently observed along the transverse direction in LaTe3 and CeTe3 is not observed in GdTe3.

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Mints, R. G. "Equilibrium current temperature quasi-oscillations in a mesoscopic ferromagnetic loop." Journal of Magnetism and Magnetic Materials 272-276 (May 2004): 993–94. http://dx.doi.org/10.1016/j.jmmm.2003.12.996.

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Martinez, L., and J. H. Schneibel. "Influencing the shape of creep cavities in nickel aluminides by stress changes." Journal of Materials Research 4, no. 6 (1989): 1379–84. http://dx.doi.org/10.1557/jmr.1989.1379.

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A nickel aluminide of composition Ni–23.5Al–0.5Hf–0.2B (at. %) is found to develop intergranular cavities with a quasi-equilibrium shape when it is creep deformed at high temperatures and low stresses. When the temperature is lowered and the stress significantly increased (by a factor of 10), crack-like noses form at the tips of the original quasi-equilibrium cavities. Although this observation is in general agreement with previously published computer simulations, certain complications are found as well. The experimental and theoretical relationships between growth rates and sizes of the crack-like noses are inconsistent, and growth rates vary from nose to nose. Possible reasons for these effects are discussed.

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FISCHER, UWE R., and GRIGORI E. VOLOVIK. "THERMAL QUASI-EQUILIBRIUM STATES ACROSS LANDAU HORIZONS IN THE EFFECTIVE GRAVITY OF SUPERFLUIDS." International Journal of Modern Physics D 10, no. 01 (2001): 57–88. http://dx.doi.org/10.1142/s0218271801000962.

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We give an account of the physical behaviour of a quasiparticle horizon due to non-Lorentz invariant modifications of the effective spacetime experienced by the quasiparticles ("matter") for high momenta. By introducing a "relativistic" conserved energy–momentum tensor, we derive quasi-equilibrium states of the fluid across the "Landau" quasiparticle horizon at temperatures well above the quantum Hawking temperature. Nonlinear dispersion of the quasiparticle energy spectrum is instrumental for quasiparticle communication and exchange across the horizon. It is responsible for the establishment of the local thermal equilibrium across the horizon with the Tolman temperature being inhomogeneous behind the horizon. The inhomogeneity causes relaxation of the quasi-equilibrium states due to scattering of thermal quasiparticles, which finally leads to a shrinking black hole horizon. This process serves as the classical thermal counterpart of the quantum effect of Hawking radiation and will allow for an observation of the properties of the horizon at temperatures well above the Hawking temperature. We discuss the thermal entropy related to the horizon. We find that only the first nonlinear correction to the energy spectrum is important for the thermal properties of the horizon. They are fully determined by an energy of order E Planck (T/E Planck )1/3, which is well below the Planck energy scale E Planck , so that Planck scale physics is not involved in determining thermal quantities related to the horizon.

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Sidler, Dominik, and Sereina Riniker. "Fast Nosé–Hoover thermostat: molecular dynamics in quasi-thermodynamic equilibrium." Physical Chemistry Chemical Physics 21, no. 11 (2019): 6059–70. http://dx.doi.org/10.1039/c8cp06800c.

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An extension of the Nosé–Hoover thermostat equation for molecular dynamics (MD) simulation is introduced, which perturbs fast degrees of freedom out of canonical equilibrium, while preserving the average temperature of the system.

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Samelson, R. M., E. D. Skyllingstad, D. B. Chelton, S. K. Esbensen, L. W. O'Neill, and N. Thum. "On the Coupling of Wind Stress and Sea Surface Temperature." Journal of Climate 19, no. 8 (2006): 1557–66. http://dx.doi.org/10.1175/jcli3682.1.

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Abstract A simple quasi-equilibrium analytical model is used to explore hypotheses related to observed spatial correlations between sea surface temperatures and wind stress on horizontal scales of 50–500 km. It is argued that a plausible contributor to the observed correlations is the approximate linear relationship between the surface wind stress and stress boundary layer depth under conditions in which the stress boundary layer has come into approximate equilibrium with steady free-atmospheric forcing. Warmer sea surface temperature is associated with deeper boundary layers and stronger wind stress, while colder temperature is associated with shallower boundary layers and weaker wind stress. Two interpretations of a previous hypothesis involving the downward mixing of horizontal momentum are discussed, and it is argued that neither is appropriate for the warm-to-cold transition or quasi-equilibrium conditions, while one may be appropriate for the cold-to-warm transition. Solutions of a turbulent large-eddy simulation numerical model illustrate some of the processes represented in the analytical model. A dimensionless ratio γτA is introduced to measure the relative influence of lateral momentum advection and local surface stress on the boundary layer wind profile. It is argued that when γτA &lt; 1, and under conditions in which the thermodynamically induced lateral pressure gradients are small, the boundary layer depth effect will dominate lateral advection and control the surface stress.

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Bakhtiyarli, I. B., V. S. Mammadov, Z. M. Mukhtarova, and A. S. Abdullayeva. "PHASE EQUILIBRIUM IN THE QUASI-TERNARY SYSTEM Y2O2S–Ga2S3–Tb2O2S." Azerbaijan Chemical Journal, no. 1 (March 28, 2023): 55–63. http://dx.doi.org/10.32737/0005-2531-2023-1-55-63.

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The results of the study of quasibinary (lateral) and non-quasibinary polythermal sections in quadrilateral systems Y2O2S–Ga2S3–Tb2O2S show the prognosis of the established liquidity surface, where the nature of the chemical interaction is relatively simple. Thus, the Ga2S3–Y2O2S və Ga2S3–Tb2O2S sides of a quasi-triangular system are quasi-binary eutectic systems with a limited solubility based on both components. On the Y2O2S–Tb2O2S side, a continuous solid solution area is formed. Thus, in the Y2O2S–Ga2S3–Tb2O2S quasi-triangular system, crystallization ends not at the non-variant triple point, but at the low-temperature binary non-variant (eutectic e1).

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Lin, Jia-Lin, Taotao Qian, Toshiaki Shinoda, and Shuanglin Li. "Is the Tropical Atmosphere in Convective Quasi-Equilibrium?" Journal of Climate 28, no. 11 (2015): 4357–72. http://dx.doi.org/10.1175/jcli-d-14-00681.1.

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Abstract The hypothesis of convective quasi-equilibrium (CQE) has dominated thinking about the interaction between deep moist convection and the environment for at least two decades. In this view, deep convection develops or decays almost instantly to remove any changes of convective instability, making the tropospheric temperature always tied to the boundary layer moist static energy. The present study examines the validity of the CQE hypothesis at different vertical levels using long-term sounding data from tropical convection centers. The results show that the tropical atmosphere is far from the CQE with much weaker warming in the middle and upper troposphere associated with the increase of boundary layer moist static energy. This is true for all the time scales resolved by the observational data, ranging from hourly to interannual and decadal variability. It is possibly caused by the ubiquitous existence of shallow convection and stratiform precipitation, both leading to sign reversal of heating from lower to upper troposphere. The simulations by 42 global climate models from phases 3 and 5 of the Coupled Model Intercomparsion Project (CMIP3 and CMIP5) are also analyzed and compared with the observations.

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Disa, A. S., J. Curtis, M. Fechner, et al. "Photo-induced high-temperature ferromagnetism in YTiO3." Nature 617, no. 7959 (2023): 73–78. http://dx.doi.org/10.1038/s41586-023-05853-8.

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AbstractIn quantum materials, degeneracies and frustrated interactions can have a profound impact on the emergence of long-range order, often driving strong fluctuations that suppress functionally relevant electronic or magnetic phases1–7. Engineering the atomic structure in the bulk or at heterointerfaces has been an important research strategy to lift these degeneracies, but these equilibrium methods are limited by thermodynamic, elastic and chemical constraints8. Here we show that all-optical, mode-selective manipulation of the crystal lattice can be used to enhance and stabilize high-temperature ferromagnetism in YTiO3, a material that shows only partial orbital polarization, an unsaturated low-temperature magnetic moment and a suppressed Curie temperature, Tc = 27 K (refs. 9–13). The enhancement is largest when exciting a 9 THz oxygen rotation mode, for which complete magnetic saturation is achieved at low temperatures and transient ferromagnetism is realized up to Tneq > 80 K, nearly three times the thermodynamic transition temperature. We interpret these effects as a consequence of the light-induced dynamical changes to the quasi-degenerate Ti t2g orbitals, which affect the magnetic phase competition and fluctuations found in the equilibrium state14–20. Notably, the light-induced high-temperature ferromagnetism discovered in our work is metastable over many nanoseconds, underscoring the ability to dynamically engineer practically useful non-equilibrium functionalities.

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Demokritov, S. O., V. E. Demidov, O. Dzyapko, et al. "Bose–Einstein condensation of quasi-equilibrium magnons at room temperature under pumping." Nature 443, no. 7110 (2006): 430–33. http://dx.doi.org/10.1038/nature05117.

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Panasenko, L. N., G. S. Romanov, Yu A. Stankevich, and K. L. Stepanov. "Quasi-equilibrium states of a low-temperature air plasma of reduced density." Journal of Engineering Physics and Thermophysics 68, no. 4 (1996): 464–69. http://dx.doi.org/10.1007/bf00858660.

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Mamonova, Veronika E., Elena V. Shubnikova, Marina V. Arapova, Olga A. Bragina, and Alexander P. Nemudry. "Quasi-equilibrium oxygen release from oxides used as electrodes in solid oxide fuel cells and electrolyzers." Electrochemical Energetics 24, no. 4 (2024): 211–15. https://doi.org/10.18500/1608-4039-2024-24-4-211-215.

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The dependence of oxygen stoichiometry on the oxygen partial pressure and the temperature for La- and Nb-doped strontium ferrite La0.4Sr0.6Fe0.95Nb0.05O3 – δ (LSFNb5) was studied by quasi-equilibrium oxygen release (QEOR) method. The equilibrium diagram in the coordinates “T – lg(pO2) – 3 – δ” in the temperature range of 700–900°C and oxygen partial pressures pO2 = 10–4 – 0.2 atm was obtained. The range of stoichiometry deviation was determined, and the thermodynamic parameters of the oxygen release process were analyzed.

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Popov, M. P., A. S. Bagishev та A. P. Nemudry. "Study of high-temperature oxygen release from strontium cobaltite in quasi-equilibrium regimе". Электрохимия 60, № 1 (2024): 33–39. http://dx.doi.org/10.31857/s0424857024010043.

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In the present work, the results of high-temperature oxygen desorption from oxide with mixed conductivity composed of SrCoO3 – δ obtained via original quasi-equilibrium oxygen release technique were shown. Measurements were carried out with a characterized powder sample in a tubular reactor. The equilibrium phase diagram of the oxide in the temperature range and partial pressure of oxygen: 600–850 оC and 0.2–6⋅10-5 atm, respectively, was obtained. With the help of literary data, correlation of phase diagram regions with their corresponding structures was carried out.

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Kruchinin, Sergei P., Roberts I. Eglitis, Valery E. Novikov, Andrzej M. Oleś, and Steffen Wirth. "Control of Strongly Nonequilibrium Coherently Correlated States and Superconducting Transition Temperature." Symmetry 15, no. 9 (2023): 1732. http://dx.doi.org/10.3390/sym15091732.

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Our paper considers the possibility of the emergence and control of non-equilibrium states of a quasi-homogenous condensed medium with energy and particle flows in the phase space, which, first of all, manifest themselves in the explosive development of the asymmetry in the initially symmetric equilibrium system. This symmetry breaking and the appearance of non-equilibrium in the system are controlled by the coherent acceleration of the system. Dependencies of thermodynamic parameters of a strong nonequilibrium system on the indices of disequilibrium in coherently correlated states are given, and the estimates of the dielectric permittivity in a non-equilibrium system and modes of plasma acoustic oscillations are made. An estimate of the superconducting transition temperature under nonequilibrium conditions has been made. It is demonstrated that the superconducting transition temperature can approach the limiting value, corresponding to a quantum with its plasma frequency of the medium.

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POPOV, M. P., M. I. GONGOLA, R. D. GUSKOV, I. V. KOVALEV та A. P. NEMUDRY. "HIGH-TEMPERATURE OXYGEN RELEASE FROM YBACO2O6-δ DOUBLE PEROVSKITE IN THE QUASI-EQUILIBRIUM REGIME". Chemistry for Sustainable Development 32, № 5 (2024): 646–52. https://doi.org/10.15372/csd2024599.

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The results of studying high-temperature oxygen desorption from an YBaCo2O6-δ oxide in the quasi-equilibrium regime are presented. The solid-phase synthesis of the oxide, ways and methods of its characterisation are described. The data obtained by quasi-equilibrium oxygen release technique allowed us to provide a reliable description of oxygen desorption from the oxide and to calculate the change in oxygen content in the oxide. Oxygen content in YBaCo2O6-δ is determined as a continuous function of temperature and the partial pressure of oxygen within the ranges of 600-900 °C and 0.2-10-5 atm, respectively. The data obtained make it possible to identify the conditions of phase transitions in the oxide and determine the stability regions of the conductive phase, which is necessary for the development of cathode materials for solid oxide fuel cells.

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Tsizh, B., and Z. Dziamski. "Production of thin film of multicomponent inorganic semiconductors under quasi-equilibrium conditions." Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies 24, no. 97 (2022): 3–8. http://dx.doi.org/10.32718/nvlvet-f9701.

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Issues of improving the properties of semiconductor thin film and their reproducibility, as well as improving and reducing the cost of manufacturing technology stimulate research and development of new, advanced methods. Therefore, it is important to optimize the technology of getting reproducible, competitive, high-tech thin films of multicomponent semiconductor compounds with predetermined properties. In the given article it is shown that constructive and technological improvements of a method of thermal spraying in vacuum allow to minimize nonequilibrium conditions of film growth, keeping the advantages of thermovacuum spraying, such as high reproducibility, processability and productivity, a wide range of variations in the synthesis conditions, and, accordingly, the properties of condensates, maximum purity of growth processes, as well as ease of performing and management and cost-effectiveness of the process of getting perfect condensates. For this purpose, we have developed a special construction of a quasi-fusion evaporator and a device for getting semiconductor film in vacuum, as well as a version of a transparent “hot wall”. The resistivity, cross section and geometric dimensions of the cover and the heater of the developed structures were selected so that in the mode of resistive heating of the evaporator temperature gradient due to the difference in their electrical resistance, and, accordingly, the Joule heat of current, in the temperature range 673… 1473 K provided the temperature of the cover 1.1 ... 1.3 times higher than the temperature of the heater. Due to the elevated temperature of the cover, the solid fraction is either repelled on the sublimating (evaporating) surface and the walls of the crucible, or undergoes sublimation (evaporation) from the surface of the cover. Depending on the values of the sputtering rate, the grain size of semiconductor polycrystalline film varied from units of nanometers to several micrometers. Crystallinely ordered films were got at relatively low values of the sputtering rate (0.5...5 nm·s-1). It was set up the technological conditions for getting thin films of multicomponent semiconductors, which ensure the independence of the chemical composition of condensates from the evaporation rate in the wide range from 0.05 to 20 nm·s-1, uniform composition of the gas phase during sublimation, absence of inhomogeneous solids in films, wide range properties of condensates and their high reproducibility.

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Hou, H. J., W. X. Chen, S. R. Zhang, X. W. Lu, and L. H. Xie. "Electronic structure, elastic and thermodynamic properties of SnS from theoretical study." Chalcogenide Letters 19, no. 12 (2022): 927–38. http://dx.doi.org/10.15251/cl.2022.1912.927.

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In this work, first-principles methods based on density functional theory are used to study the structural, electronic and elastic properties of rock-salt SnS in detail. Thermodynamic properties of SnS under high temperature and high pressure were studied by using the quasi-harmonic Debye model. The results show that the optimized structural parameters are in good agreement with the experimental and other theoretical values. The band structure and density of states of SnS are obtained by calculation and analysis. Based on the quasi-harmonic Debye method, the pressure and temperature dependencies of the equilibrium volume, the bulk modulus, the Debye temperature and so on are obtained.

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Arita, Minoru. "Thermodynamics of high-temperature cuprous sulfide." International Journal of Materials Research 97, no. 9 (2006): 1251–63. http://dx.doi.org/10.1515/ijmr-2006-0198.

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Abstract Published measurements of the diatomic sulfur fugacity were used to make a thermodynamic analysis of high-temperature cuprous sulfide between 789 K and 1321 K. Gibbs–Duhem integration of the fugacity data was used to determine the enthalpy of formation of stoichiometric Cu2S as – 123.8 kJ mol–1. Statistical thermodynamics was applied to find partition functions, interaction energies, and free energies to characterize the configurational aspects of the phase. Theoretical calculations indicated that Cu vacancies might be localized in one half of the Cu lattice sites under quasi-chemical equilibrium.

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Morozov, Vladimir, and Vasyl’ Ignatyuk. "Energy Conservation and the Correlation Quasi-Temperature in Open Quantum Dynamics." Particles 1, no. 1 (2018): 285–95. http://dx.doi.org/10.3390/particles1010023.

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The master equation for an open quantum system is derived in the weak-coupling approximation when the additional dynamical variable—the mean interaction energy—is included into the generic relevant statistical operator. This master equation is nonlocal in time and involves the “quasi-temperature”, which is a non- equilibrium state parameter conjugated thermodynamically to the mean interaction energy of the composite system. The evolution equation for the quasi-temperature is derived using the energy conservation law. Thus long-living dynamical correlations, which are associated with this conservation law and play an important role in transition to the Markovian regime and subsequent equilibration of the system, are properly taken into account.

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Ahmed, Fiaz, J. David Neelin, and Ángel F. Adames. "Quasi-Equilibrium and Weak Temperature Gradient Balances in an Equatorial Beta-Plane Model." Journal of the Atmospheric Sciences 78, no. 1 (2021): 209–27. http://dx.doi.org/10.1175/jas-d-20-0184.1.

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AbstractConvective quasi-equilibrium (QE) and weak temperature gradient (WTG) balances are frequently employed to study the tropical atmosphere. This study uses linearized equatorial beta-plane solutions to examine the relevant regimes for these balances. Wave solutions are characterized by moisture–temperature ratio (q–T ratio) and dominant thermodynamic balances. An empirically constrained precipitation closure assigns different sensitivities of convection to temperature (εt) and moisture (εq). Longwave equatorial Kelvin and Rossby waves tend toward the QE balance with q–T ratios of εt:εq that can be ~1–3. Departures from strict QE, essential to both precipitation and wave dynamics, grow with wavenumber. The propagating QE modes have reduced phase speeds because of the effective gross moist stability meff, with a further reduction when εt > 0. Moisture modes obeying the WTG balance and with large q–T ratios (>10) emerge in the shortwave regime; these modes exist with both Kelvin and Rossby wave meridional structures. In the υ = 0 case, long propagating gravity waves are absent and only emerge beyond a cutoff wavenumber. Two bifurcations in the wave solutions are identified and used to locate the spatial scales for QE–WTG transition and gravity wave emergence. These scales are governed by the competition between the convection and gravity wave adjustment times and are modulated by meff. Near-zero values of meff shift the QE–WTG transition wavenumber toward zero. Continuous transitions replace the bifurcations when meff < 0 or moisture advection/WISHE mechanisms are included, but the wavenumber-dependent QE and WTG balances remain qualitatively unaltered. Rapidly decaying convective/gravity wave modes adjust to the slowly evolving QE/WTG state in the longwave/shortwave regimes, respectively.

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Popov, M. P., A. S. Bagishev, and A. P. Nemudry. "Study of High-Temperature Oxygen Release from Strontium Cobaltite in Quasi-Equilibrium Regime." Russian Journal of Electrochemistry 60, no. 1 (2024): 25–29. http://dx.doi.org/10.1134/s1023193524010075.

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Tropin, E. S., M. P. Popov, R. D. Gus’kov та A. P. Nemudry. "High-Temperature Oxygen Release from Complex Oxide La2NiO4 + δ in Quasi-Equilibrium Mode". Russian Journal of Electrochemistry 60, № 3 (2024): 211–15. http://dx.doi.org/10.1134/s102319352403011x.

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30

Дедков, Г. В., та А. А. Кясов. "Тепловое излучение абсолютно черного тела, движущегося в равновесном газе фотонов". Журнал технической физики 91, № 7 (2021): 1075. http://dx.doi.org/10.21883/jtf.2021.07.50947.343-20.

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The dynamics, kinetics of heat transfer and the intensity of thermal radiation of an absolutely black body with its own temperature T1 moving at an arbitrary speed in an equilibrium gas of photons with its own temperature T2 independent of time are considered. Formulas are obtained for the spectral-angular and total radiation intensity, as well as for other quantities in the rest frame of the body and in the frame of reference of the photon gas. It is shown that at the initial moment the radiation intensity of spherical and disk-shaped particles of the same radius depends differently on the speed of motion and the ratio of temperatures T1 and T2. Then a quasi-stationary thermal state of bodies is established with an effective temperature depending on the velocity and temperature T2, the intensity of thermal radiation does not depend on the shape, and the kinetic energy is transformed into radiation. The characteristic time for the establishment of a quasi-stationary state is many orders of magnitude shorter than the characteristic deceleration time.

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Kipiani, G., N. Gasviani, M. Khustisvili, et al. "HIGH-TEMPERATURE ELECTROCHEMICAL SYNTHESIS OF ITTRIUM-MOLIBDENUM INTERMETALLIDE FROM OXYHALIDE MELTS." Slovak international scientific journal, no. 71 (May 11, 2023): 3–8. https://doi.org/10.5281/zenodo.7925026.

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The joint electrochemical reduction on a platinum electrode of yttrium and molybdenum from oxyhalide melts was studied by the potentiostatic method, at a temperature of 1073K. The mechanism and kinetics of the reduction of yttrium trifluoride and sodium molybdate, both separately and in their joint presence in the melt, have been investigated. Due to the mutual influence of these depolarizers there occurred a convergence of electrochemical reduction potentials yttrium and molybdenum ions, which made it possible to control the process in an equilibrium (quasi-equilibrium) mode and carry out multi-electrode reduction processes of these metals in one stage. A mixture of powders of intermetallic compounds MoY2 and MoY3 was obtained from oxyhalide melts.

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32

Wiguno, Annas, Asalil Mustain, Wahyu Fazar Eka Irwansyah, and Gede Wibawa. "Isothermal Vapor-Liquid Equilibrium of Methanol + Glycerol and 1-Propanol + Glycerol." Indonesian Journal of Chemistry 16, no. 1 (2018): 111. http://dx.doi.org/10.22146/ijc.21186.

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Isothermal vapor-liquid equilibrium (VLE) data for two binary mixtures of methanol + glycerol and 1-propanol + glycerol were determined at the temperature range from (313.15 to 363.15) K using a simple quasi-static ebulliometer. All systems showed that the vapor pressures increased with increasing alcohols (methanol or 1-propanol) concentrations at corresponding system. The Wilson, Non-Random Two-Liquid (NRTL) and Universal Quasi-Chemical (UNIQUAC) activity coefficient models were used to correlate the experimental data. Both systems showed slightly deviations from the ideal liquid phase behavior.

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Waller, Matthew D., Charles E. Bakis, Kevin L. Koudela, and Sean M. McIntyre. "Processing and properties of low-temperature cure carbon fiber-reinforced bismaleimide composite." Journal of Composite Materials 56, no. 8 (2022): 1191–209. http://dx.doi.org/10.1177/00219983211070348.

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Bismaleimide (BMI) resins are used in carbon fiber reinforced composites for high-temperature applications. Conventional BMI resins require high cure and post-cure processing temperatures, which limit fabrication methods and contribute to residual stress and microcracking. Recently, BMIs with lower cure temperatures have been developed; however, little data on the properties of low-temperature cure carbon/BMI composites are available in the open literature. In this study, processing and properties of a low-temperature cure BMI resin system, referred to here as BMI-2, were evaluated. Along with evaluation of neat resin properties, multi-directional woven carbon fiber reinforced BMI-2 composite laminates were fabricated by an out-of-autoclave, vacuum-bag-only resin infusion method. New data on the mechanical, thermal, and moisture absorption properties are presented. It was found that the resin infusion method produced laminates with fiber volume fraction of approximately 55% and immeasurably low void content. BMI-2 was found to attain a degree of cure of 96% and glass transition temperature of 366°C following a 163°C cure cycle. Cured laminates did not suffer from process-induced cracking at the inter- or intra-laminar levels. Tensile strength and modulus of quasi-isotropic specimens with woven AS4 carbon fiber were 443 MPa and 47.6 GPa, respectively, and failure under quasi-static tension occurred by delamination. Compression strength was stable across a wide temperature range, with quasi-isotropic specimens retaining 60% of their room temperature compression strength at 260°C. Equilibrium moisture content of composite specimens was 1.2% by weight.

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Altoiz, B. A., A. Yu Popovskii, and A. F. Butenko. "Equilibrium parameters of a structured n-hexadecane layer." Physics of Aerodisperse Systems, no. 54 (December 14, 2017): 35–44. http://dx.doi.org/10.18524/0367-1631.2017.54.132718.

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The temperature dependences of the structural characteristics of the quasi-liquidcrystalline n-hexadecane layers − their equilibrium thickness and the degree of orientational order were determined by such optical methods as measurements of admixture dichroism and the anisotropy of heterophase interlayers. The values of these epitropic liquid-crystalline layer parameters were compared with those established earlier in rheological experiments.

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35

Mustain, Asalil, Anang Takwanto, and Dhoni Hartanto. "PARAMETER INTERAKSI BINER KESETIMBANGAN UAP-CAIR CAMPURAN ALKOHOL UNTUK OPTIMASI PROSES PEMURNIAN BIOETANOL." Jurnal Bahan Alam Terbarukan 5, no. 2 (2017): 37–44. http://dx.doi.org/10.15294/jbat.v4i2.5126.

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In this work, the binary interaction parameters of vapor-liquid equilibrium for the mixtures of primary alcohols (methanol, ethanol, 1-propanol or 1-butanol) with C5 alcohols were obtained. A total of 15 systems that consisted of isobaric vapor-liquid equilibrium data at atmospheric pressure were selected. The binary interaction parameters were determined as temperature function by correlating the selected vapor-liquid equilibrium data using the Wilson, Non-Random Two-Liquid (NRTL) and Universal Quasi-Chemical (UNIQUAC) activity coefficient models. The binary interaction parameters were described as the temperature-dependent to increase the capability of the parameters for the application in wide range of temperature. The correlation showed good results because the root mean square deviation (RMSD) between the calculation values and experimental data were relatively low. The obtained parameters were very useful for optimizing the distillation column in the bio-ethanol purification process.

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Raste, Janakee, Anjan Kumar Sarkar та Shiv K. Sethi. "Thermal Evolution of the Intergalactic Medium due to Lyα Photons during the Cosmic Dawn". Astrophysical Journal 976, № 2 (2024): 236. http://dx.doi.org/10.3847/1538-4357/ad84ec.

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Abstract The first star-forming objects that formed at high redshifts during the cosmic dawn (CD) also emitted photons between Lyα and Lyman-limit frequencies. These photons are instrumental in coupling the spin temperature of the neutral hydrogen (H i) atoms with the kinetic temperature of the intergalactic medium (IGM). Along with this coupling effect, these photons also impact the kinetic temperature by exchanging energy with the H i atoms. The injected Lyα photons in general cool the medium, while the continuum photons heat the medium. While studying this effect in the literature, a quasi-static profile around the Lyα frequency is assumed. In this paper, we solve the time-dependent coupled dynamics of the photon intensity profile along with the evolution of the thermal state of the IGM and H i spin temperature. It is expected that, during the CD era, the IGM has a mix of continuum photons with 10%–20% of injected photons. For this case, we show that the system reaches thermal equilibrium in around 1 Myr, with the final temperature in the range 50–100 K. This timescale is comparable to the source lifetime of Population III stars at high redshifts. One impact of switching off short-lived sources is that it can keep the system heated above the temperature of the quasi-static state. We also show that the quasi-static equilibrium for the continuum photons is only achieved on timescales of 100 Myr at z ≃ 20, comparable to the age of the Universe. We also briefly discuss how the Lyα induced heating can impact the 21 cm signal from CD.

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Mammadli, P. R. "PHYSICO-CHEMICAL INTERACTION OF THE COPPER AND ANTIMONY IODIDES." Azerbaijan Chemical Journal, no. 1 (April 9, 2021): 43–47. http://dx.doi.org/10.32737/0005-2531-2021-1-43-47.

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The character of the mutual interaction of the components in the CuI-SbI3 system was studied by differential thermal analysis and X-ray phase analysis methods and its phase diagram was constructed. It was found that the system is quasi-binary and forms a monotectic phase diagram. The immiscibility region covers ~15-93 mol% SbI3 concentration interval at the monotectic equilibrium temperature (~ 4930С). The temperatures of polymorphic transformations of the CuI compound in the system drop slightly and these phase transitions take place by metatectic reactions

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38

Byrne, Michael P., and Paul A. O’Gorman. "Land–Ocean Warming Contrast over a Wide Range of Climates: Convective Quasi-Equilibrium Theory and Idealized Simulations." Journal of Climate 26, no. 12 (2013): 4000–4016. http://dx.doi.org/10.1175/jcli-d-12-00262.1.

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Abstract Surface temperatures increase at a greater rate over land than ocean in simulations and observations of global warming. It has previously been proposed that this land–ocean warming contrast is related to different changes in lapse rates over land and ocean because of limited moisture availability over land. A simple theory of the land–ocean warming contrast is developed here in which lapse rates are determined by an assumption of convective quasi-equilibrium. The theory predicts that the difference between land and ocean temperatures increases monotonically as the climate warms or as the land becomes more arid. However, the ratio of differential warming over land and ocean varies nonmonotonically with temperature for constant relative humidities and reaches a maximum at roughly 290 K. The theory is applied to simulations with an idealized general circulation model in which the continental configuration and climate are varied systematically. The simulated warming contrast is confined to latitudes below 50° when climate is varied by changes in longwave optical thickness. The warming contrast depends on land aridity and is larger for zonal land bands than for continents with finite zonal extent. A land–ocean temperature contrast may be induced at higher latitudes by enforcing an arid land surface, but its magnitude is relatively small. The warming contrast is generally well described by the theory, although inclusion of a land–ocean albedo contrast causes the theory to overestimate the land temperatures. Extensions of the theory are discussed to include the effect of large-scale eddies on the extratropical thermal stratification and to account for warming contrasts in both surface air and surface skin temperatures.

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MERRYFIELD, WILLIAM J. "Effects of stratification on quasi-geostrophic inviscid equilibria." Journal of Fluid Mechanics 354 (January 10, 1998): 345–56. http://dx.doi.org/10.1017/s0022112097007684.

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Inviscid equilibrium mean flows over topography are considered for continuously stratified quasi-geostrophic models, in contrast to previous work which has dealt with two-layer models. From the constraint of maximum entropy, an equation for the equilibrium mean flow is derived. Analytical solutions are obtained for uniform and piecewise-constant stratifications. With increasing stratification, the mean streamfunction becomes increasingly bottom intensified. Bottom trapping becomes ever more pronounced on smaller scales, but can remain significant even on the largest scales. When boundary temperature is uniform, transport is shown to be independent of stratification, other factors being equal. Although two-layer models share this property, they represent poorly the energetics of the continuous system when bottom trapping is significant.

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Patra, Anshuman, Swapan Kumar Karak, and Snehanshu Pal. "Effects of Mechanical Alloying on Solid Solubility." Advanced Engineering Forum 15 (February 2016): 17–24. http://dx.doi.org/10.4028/www.scientific.net/aef.15.17.

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Mechanical alloying (MA) is a potential processing method for various equilibrium and non-equilibrium alloy phases such as supersaturated solid solution, metastable crystalline, amorphous, quasi-crystalline phases, nanostructures. Compared to conventional high temperature material processing such as melting and casting, improvement of solid solubility limit results from mechanical alloying at room temperature. The solid solubility increases with increase in milling time due to enhanced stress assisted atomic diffusion during particle refinement and reaches a saturation level at higher milling time. The extension of solid solubility is attributed to thermodynamic, dynamic or kinetic factors such as high dislocation density due to severe plastic deformation during particle refinement and enhanced diffusivity during MA. The review aims to discuss the insight of MA than other non-equilibrium processing in terms of achieving higher solubility, reasoning and mechanism of solubility improvement during MA of different alloy systems.

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41

Dzyapko, O., V. E. Demidov, G. A. Melkov, and S. O. Demokritov. "Bose–Einstein condensation of spin wave quanta at room temperature." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 369, no. 1951 (2011): 3575–87. http://dx.doi.org/10.1098/rsta.2011.0128.

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Spin waves are delocalized excitations of magnetic media that mainly determine their magnetic dynamics and thermodynamics at temperatures far below the critical one. The quantum-mechanical counterparts of spin waves are magnons, which can be considered as a gas of weakly interacting bosonic quasi-particles. Here, we discuss the room-temperature kinetics and thermodynamics of the magnon gas in yttrium iron garnet films driven by parametric microwave pumping. We show that for high enough pumping powers, the thermalization of the driven gas results in a quasi-equilibrium state described by Bose–Einstein statistics with a non-zero chemical potential. Further increases of the pumping power cause a Bose–Einstein condensation documented by an observation of the magnon accumulation at the lowest energy level. Using the sensitivity of the Brillouin light scattering spectroscopy to the degree of coherence of the scattering magnons, we confirm the spontaneous emergence of coherence of the magnons accumulated at the bottom of the spectrum, occurring if their density exceeds a critical value.

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Furman, Gregory, and Shaul Goren. "Dipolar Order and Spin-Lattice Relaxation in a Liquid Entrapped into Nanosize Cavities." Zeitschrift für Naturforschung A 66, no. 12 (2011): 779–83. http://dx.doi.org/10.5560/zna.2011-0047.

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It was shown that by means of the two-pulse sequence, the spin system of a liquid entrapped into nanosize cavities can be prepared in quasi-equilibrium states of high dipolar order, which relax to thermal equilibrium with the molecular environment with a relaxation time T1d. Measurements of the inverse dipolar temperature and spin-lattice relaxation time in the local fields provide an important information about the cavity size V, its shape F, and orientation θ (with respect to the external magnetic field) of the nanopores.

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43

Liu, Yuan, Linning Wang, and Jingjing Liang. "Effect of melt temperature on the quasi-equilibrium solidification of K465 Ni-based superalloy." Journal of Materials Research and Technology 30 (May 2024): 4487–95. http://dx.doi.org/10.1016/j.jmrt.2024.03.233.

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44

Lukyanov, Andrey Vladimirovich, and Anton Valerievich Ivanov. "Modeling of ferroelectrics based on the Fokker-Planck equation and construction of a closed system of moment equations." Keldysh Institute Preprints, no. 22 (2023): 1–12. http://dx.doi.org/10.20948/prepr-2023-22.

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The paper considers the modeling of uniaxial ionic ferroelectrics based on the Fokker-Planck equation. The equation is solved numerically using the stochastic analogue method. To describe the quasi-equilibrium state of a ferroelectric, a system of moments is constructed, which is closed using the Gaussian distribution and empirical dependence of critical temperature on key parameters. It is shown that the resulting system gives acceptable results on the problem of temperature hysteresis.

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Mamedova, N. "PHASE EQUILIBRIUM IN THE Sb2Te3-HoTe3 SYSTEM." East European Scientific Journal 3, no. 10(74) (2021): 30–33. http://dx.doi.org/10.31618/essa.2782-1994.2021.3.74.141.

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The phase equilibrium of the Sb2Te3-HoTe3 system was studied by means of physical and chemical analysis methods DTA, RFA, MQA, as well as density and microhardness measurements, and its phase diagram was constructed. It has been determined that the Sb2Te3-HoTe3 system is a partial quasi-binary cross section of the ternary Bi-Ho-Te system. The system undergoes a process of eutectic equilibrium and peritectic transformation. In the Sb2Te3-HoTe3 system at room temperature, of the based Sb2Te3 solid solutions extend to 4.5 mol % and of the based HoTe3 solid solutions have practically not been established.

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46

Semikolenov, Andrey V. "Maxwell's quasi-demon as a property of an ideal gas in the equilibrium state." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 476, no. 2244 (2020): 20200232. http://dx.doi.org/10.1098/rspa.2020.0232.

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The paper shows that for the case of an ideal gas in the equilibrium state there exists a method for splitting it into portions with different temperatures without energy transfer to or from the environment and without work being done. Compared with the thought experiment known as ‘Maxwell's demon’, in which such splitting is based on sorting specific molecules according to their energy levels, the process described does not require the energy of a specific molecule to be determined. Here the splitting is guided by the average energy of a group of molecules. The paper establishes the fact that the average energy of molecules striking the wall over a period of time is higher than the average energy of all molecules constituting the gas; this fact is what substantiates our method. This explains how a process that may result in extracting a higher temperature portion of the gas in the equilibrium state is generally possible. The paper considers one of the implementations of this process. We also show that groups of molecules may be split off from the gas, the average energy of said groups being lower than the average energy of the gas molecules in total.

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Tsizh, B., and Z. Dziamski. "Technological Methods of Forming Thin Semiconductor Layers. Part 2." Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies 21, no. 92 (2019): 3–7. http://dx.doi.org/10.32718/nvlvet-f9201.

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Features and basic technological methods of formation of thin layers of semiconductor materials in a vacuum with the method of thermal spraying in a quasi-closed volume are analyzed. The disadvantages of thermal spraying of thin films of multicomponent semiconductor compounds in an open vacuum are indicated. The designs of special collapsible evaporator chambers for thermo-vacuum sputtering in a quasi-closed volume containing the raw material and substrate in quasi-isolated conditions are presented. They allow to create and manage the necessary temperature corrections between the evaporator, lining, walls and other structural elements. The designs of special collapsible evaporator chambers for thermo-vacuum sputtering in a quasi-closed volume containing the raw material and substrate in quasi-isolated conditions are presented. They allow to create and manage the necessary temperature corrections between the evaporator, lining, walls and other structural elements. It is shown that the spatial temperature distribution in the discussed constructs provides the evaporation (sublimation) of the source material, the reflection of vapor from the heated walls, the intensive exchange interaction between the gas phase and the condensation surfaces and the prevailing condensation on the substrate surface, which contributes to the diffusion mechanism of the transfer of matter and to the thermodynamically balanced growth process for films. It is shown that for all modifications, to a greater or lesser extent, the conditions for the isolation of the localized volume and the equilibrium of the condensation process are fulfilled by creating the necessary temperature gradient. It is indicated that it is problematic to use such structures for mass production due to their complexity and technological features. That is why the method of thermal spraying of thin films in the quasi-closed volume is most often used in the production of epitaxial monocrystalline layers for scientific research and experimental development, and for industrial production it is very effective to develop methods for obtaining thin films, which from one hand combine universality of thermal spraying in opened vacuum and from another hand allow to bring the processes of evaporation (sublimation) and condensation closer to thermodynamic equilibrium, for example, various types of “hot walls”. It is noted that the analyzed methods or their modifications are these necessary methods of creating thin-film semiconductor structures with predetermined properties.

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Thiagarajan, Nivedita, Hao Xie, Camilo Ponton, et al. "Isotopic evidence for quasi-equilibrium chemistry in thermally mature natural gases." Proceedings of the National Academy of Sciences 117, no. 8 (2020): 3989–95. http://dx.doi.org/10.1073/pnas.1906507117.

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Natural gas is a key energy resource, and understanding how it forms is important for predicting where it forms in economically important volumes. However, the origin of dry thermogenic natural gas is one of the most controversial topics in petroleum geochemistry, with several differing hypotheses proposed, including kinetic processes (such as thermal cleavage, phase partitioning during migration, and demethylation of aromatic rings) and equilibrium processes (such as transition metal catalysis). The dominant paradigm is that it is a product of kinetically controlled cracking of long-chain hydrocarbons. Here we show that C2+n-alkane gases (ethane, propane, butane, and pentane) are initially produced by irreversible cracking chemistry, but, as thermal maturity increases, the isotopic distribution of these species approaches thermodynamic equilibrium, either at the conditions of gas formation or during reservoir storage, becoming indistinguishable from equilibrium in the most thermally mature gases. We also find that the pair of CO2 and C1 (methane) exhibit a separate pattern of mutual isotopic equilibrium (generally at reservoir conditions), suggesting that they form a second, quasi-equilibrated population, separate from the C2 to C5 compounds. This conclusion implies that new approaches should be taken to predicting the compositions of natural gases as functions of time, temperature, and source substrate. Additionally, an isotopically equilibrated state can serve as a reference frame for recognizing many secondary processes that may modify natural gases after their formation, such as biodegradation.

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Bellon, Gilles, and Adam H. Sobel. "Multiple Equilibria of the Hadley Circulation in an Intermediate-Complexity Axisymmetric Model." Journal of Climate 23, no. 7 (2010): 1760–78. http://dx.doi.org/10.1175/2009jcli3105.1.

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Abstract A model of intermediate complexity based on quasi-equilibrium theory—a version of the Quasi-Equilibrium Tropical Circulation Model with a prognostic atmospheric boundary layer, as well as two free-tropospheric modes in momentum, and one each in moisture and temperature—is used in a zonally symmetric aquaplanet configuration to study the sensitivity of the Hadley circulation to the sea surface temperature (SST) latitudinal distribution. For equatorially symmetric SST forcing with large SST gradients in the tropics, the model simulates the classical double Hadley cell with one equatorial intertropical convergence zone (ITCZ). For small SST gradients in the tropics, the model exhibits multiple equilibria, with one equatorially symmetric equilibrium and two asymmetric equilibria (mirror images of each other) with an off-equatorial ITCZ. Further investigation of the feedbacks at play in the model shows that the assumed vertical structure of temperature variations is crucial to the existence and stability of the asymmetric equilibria. The free-tropospheric moisture–convection feedback must also be sufficiently strong to sustain asymmetric equilibria. Both results suggest that the specific physics of a given climate model condition determine the existence of multiple equilibria via the resulting sensitivity of the convection to free-tropospheric humidity and the vertical structure of adiabatic heating. The symmetry-breaking mechanism and resulting multiple equilibria have their origin in the local multiple equilibria that can be described by a single-column model using the weak temperature gradient approximation. An additional experiment using an SST latitudinal distribution with a relative minimum at the equator shows that the feedbacks controlling these multiple equilibria might be relevant to the double-ITCZ problem.

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Deng, Yong He. "Study of the Mechanical and Thermodynamic Properties on NiAl and Ni₃Al." Applied Mechanics and Materials 584-586 (July 2014): 1256–63. http://dx.doi.org/10.4028/www.scientific.net/amm.584-586.1256.

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The stuctural, elastic and thermodynamic properties of B2-NiAl and L12-Ni3Al intermetallic compounds are systemically investigated. Using a first principle pseudopotential plane-wave method, several basic mechanical parameters of B2-NiAl and L12-Ni3Al crystals, such as the equilibrium volume, the bulk modulus, the elastic constants, the Zener anisotropy factor, the Poisson’s ratio, the Young’s modulus and isotropic shear modulus are firstly calculated. And then the temperature dependence of the equilibrium volume, the bulk modulus, the thermal expansion coefficient, the heat capacity, the Debye temperature and the Grüneisen parameter are further evaluated in the framework of a quasi-harmonic Debye model. Finally, a special attention is paied on the mutual influence of pressure and temperature on mechenical and thermodynanic properties of B2-NiAl and L12-Ni3Al intermetallic compounds in the range of 0-20 GPa and 0-1000 K.

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Journal articles on the topic 'Quasi-equilibrium temperature'

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