Battery energy storage systems become increasingly important to address the intermittency of renewable energies, but their widespread adoption is still hindered by thermal concerns. However, a single thermal managemen...
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Supercritical multiple mixtures (H2O/CO2) fluids are produced in the poly-generation system based on supercritical water gasification (SCWG). Understanding the thermophysical property of supercritical multiple mixture...
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Supercritical multiple mixtures (H2O/CO2) fluids are produced in the poly-generation system based on supercritical water gasification (SCWG). Understanding the thermophysical property of supercritical multiple mixtures fluid is rather essential to design and industrialize the poly-generation system. At present, the selection of force field models for H2O/CO2 mixtures are rather complicated, chaotic and inconsistent, the calculation of each parameter necessitates the use of one force field model. There is no universal force field model to calculate and conduct thermophysical property of H2O/CO2 at one time in a wide range of temperature within SCW. In this paper, heat capacity, viscosity and thermal conductivity of multiple mixtures in supercritical and near-critical water (575 K–1.75 k) are first investigated via a novel common force field model with molecular dynamics (MD) simulations. The effects of different factors including the pressure, temperature and CO2 mass fraction on thermophysical properties of H2O/CO2 at a wide range of temperature were first analyzed and conducted in detail. The calculated results indicate that the phenomenon "critical point drift" for viscosity and thermal conductivity of H2O/CO2 mixtures migrating toward the low temperature region occurs. The drift values of viscosity and thermal conductivity are about 1. K and 28 K. The variation of heat capacity and viscosity of H2O/CO2 mixtures increases with increasing pressures only in low temperatures region (700 K-–800 K), while the thermal conductivity always increases with increasing pressures. When the mass fractions of CO2 increases from 20 % to 40 % and 60 %, the drift values for thermal conductivity and viscosity of H2O/CO2 mixtures decreases from 628 K to 624 K and 620 K, and from 627 K to 61. K and 61. K, respectively, and the peak heat capacity decreases from 64.9 J/mol·K to 52.4 J/mol·K and 45.1.J/mol·K. The fitting polynomial to determine conductivity, viscosity and heat capacity H
Multi-stream mixing is common in practice but cannot be modeled using the traditional Bilger mixture fraction defined for only two streams. This work was intended to define the multi-stream mixture fractions that can ...
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Due to the great compactness and ease of operation, the rotary adsorption and desorption wheel (RADW) is applicable for carbon capture in power plants using temperature swing adsorption (TSA). Commercial CFD-based sof...
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Supercritical carbon dioxide (S-CO2) nuclear energy and power systems have garnered significant attention for {1. and heat transfer experiments because of their compact design, advanced circulation methods, and high ...
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Selective oxidation of amines to imines through electrocatalysis is an attractive and efficient way for the chemical industry to produce nitrile compounds,but it is limited by the difficulty of designing efficient cat...
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Selective oxidation of amines to imines through electrocatalysis is an attractive and efficient way for the chemical industry to produce nitrile compounds,but it is limited by the difficulty of designing efficient catalysts and lack of understanding the mechanism of ***,we demonstrate a novel strategy by generation of oxyhydroxide layers on two-dimensional iron-doped layered nickel phosphorus trisulfides(Ni1.xFexPS_(3))during the oxidation of benzylamine(BA).In-depth structural and surface chemical characterizations during the electrocatalytic process combined with theoretical calculations reveal that Ni(1.x)FexPS_(3) undergoes surface reconstruction under alkaline conditions to form the metal oxyhydroxide/phosphorus trichalcogenide(NiFeOOH/Ni1.xFexPS_(3))***,the generated heterointerface facilitates BA oxidation with a low onset potential of 1.39 V and Faradaic efficiency of 53%for benzonitrile(BN)*** calculations further indicate that the as-formed NiFeOOH/Ni1.xFexPS_(3) heterostructure could offer optimum free energy for BA adsorption and BN desorption,resulting in promising BN synthesis.
Mesoscale drag modeling for gas-solid flows is typically based on fully-periodic systems where fluid convection is insignificant. This study examines a series of 2D sudden-expanded fluidized beds (SEFBs) to investigat...
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The cations can significantly affect the interfacial dynamics of asphaltene molecules, which greatly change the mechanics of oil–water interfaces and thus have a remarkable impact on the chemical flooding process of ...
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The cations can significantly affect the interfacial dynamics of asphaltene molecules, which greatly change the mechanics of oil–water interfaces and thus have a remarkable impact on the chemical flooding process of heavy oil. However, Due to the weak amphiphilic property of asphaltene, the effects of cations on the interfacial behaviors of asphaltene as well as the interfacial mechanics are still unclear. Here, we study the effects of different types and concentrations of cations (Na+, Ca2+ and Mg2+) on the interfacial tension of oil–water systems with different asphaltenes (C5Pe) concentrations by using molecular dynamics simulations. As asphaltene concentration rises, the stronger interactions between cation and asphaltene induce an interfacial enrichment of asphaltenes, resulting in a decrease of interfacial tension. The cations have a more prominent impact on the interfacial tension when the oil–water interfaces reach supersaturated adsorption state of asphaltene molecules. The interfacial tension shows a non-monotonic variation with cation concentration increasing, which has a minimum at intermediate cation concentrations in our simulations. We explain this non-monotonic dependence of interfacial tension on cation concentration by a coupling effect of cations and asphaltene molecules. Under low cation concentrations, the interaction between cations and asphaltenes gradually enhances with cation concentration increasing, leading to a weaker π–π interaction between asphaltenes. Consequently, the asphaltene aggregates disperse and individual asphaltene molecules can easily migrate to the interface. The surface density of asphaltene thus increases, causing a reduction in interfacial tension. At high cation concentrations, cations strongly shield the electrostatic attraction between asphaltene and water molecules, so that the adsorption ability of asphaltenes at interface will weaken or even desorb, thus the interfacial tension elevate. Our results reveal the under
The micro/nanoscale structures on metal surfaces are of significant research interest for boiling heat transfer and exhibit great application potential in the thermal management of high-power electronic devices. This ...
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Accurate prediction of the composition of pyrolysis products is the prerequisite for achieving directional regulation of organic-rich shale pyrolysis and conversion products. In this paper, the classical segmented pyr...
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