Activated carbon （AC） was modified by tri-butyl phosphate （TBP） for selectively extracting scandium from red mud and characterized by BET （Brunauer-Emmett-Teller） surface area. The modified AC had a preferential...
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Activated carbon （AC） was modified by tri-butyl phosphate （TBP） for selectively extracting scandium from red mud and characterized by BET （Brunauer-Emmett-Teller） surface area. The modified AC had a preferential adsorption to scandium. The influences of adsorbent dos- age, adsorption temperature, and time on adsorption capacity and selectivity to scandium were examined. An optimum adsorbent dosage （-6.25 g/L）, adsorption temperature （308 K）, and adsorption time （40 min） were figured out. A pseudo-second-order kinetics model was employed for describing the adsorption process of scandium.
In this study, α-ZrP-CPC layered compound was gained by inserting cetyl pyridinium chloride (CPC) into α-ZrP with amines as pillaring agent. The amount of CPC intercalated reached the highest with the molar ratio of...
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In this study, α-ZrP-CPC layered compound was gained by inserting cetyl pyridinium chloride (CPC) into α-ZrP with amines as pillaring agent. The amount of CPC intercalated reached the highest with the molar ratio of the amine/α-ZrP being 2. The lower concentration of CPC resulted in more CPC molecules intercalated into the interlayer of α-ZrP, The intercalation products were characterized by XRD, IR, TG-DSC and SEM. The result of TG-DSC showed that the amount of xylene adsorbed reached the peak value of 5.56%, when the content of CPC in α-ZrP-CPC was 41%.
The surface tension of molten AlSi20 alloy has been measured by using the sessile drop method at 923―1123 K under argon atmosphere in both heating-up and cooling processes. The result shows that the surface tension o...
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The surface tension of molten AlSi20 alloy has been measured by using the sessile drop method at 923―1123 K under argon atmosphere in both heating-up and cooling processes. The result shows that the surface tension of this alloy decreases as long as temperature increases. The results of surface tension and contact angles in heating-up process have differences from those obtained in cooling process, because the metal microstructures have some changes at different temperatures based on the metal genetic theory. The surface tension of molten AlSi20 alloy and that of molten pure aluminum have been compared as well, and the temperature coefficient of AlSi20 alloy is slightly lower than that of Al. The result has been analyzed by the linear scanning analysis with ESEM. The concentration of silicon in most region of the bulk is lower than that of the surface and the addition of Si to pure Al decreases the surface tension of molten pure Al.
The behavior of a single polyethylene polymer in aqueous solution confined between two hydrophilic walls is studied with molecular dynamics (MD) simulations. The thickness of the nano-slit ranges from 1.26 to 3.15 nm,...
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The behavior of a single polyethylene polymer in aqueous solution confined between two hydrophilic walls is studied with molecular dynamics (MD) simulations. The thickness of the nano-slit ranges from 1.26 to 3.15 nm, which is comparative to the polymer dimension. A monotonic transition from 3D- to 2D-like configurations is observed as the distance between the two walls narrows. Monomers are compressed into several layers and the preferred bond orientations alternate between parallel and normal to the walls accordingly. The diffusivity in the direction parallel to the wall is always larger than the one perpendicular to it. Calculation of the entropy and enthalpy changes during the folding of the polymer chain alone cannot explain the spontaneous process. The corresponding increase in water entropy due to volume expansion may be large enough to result in the overall free energy decrease.
Vibration isolation controllers are used to suppress undesirable disturbance in order to guarantee better performance in many industrial and scientific domains. To overcome the drawbacks of the conventional passive sy...
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Various process residues represent a kind of biomass resource already concentrated but containing water as much as 60 wt.%. These materials are generally treated as waste or simply combusted directly to generate heat....
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Various process residues represent a kind of biomass resource already concentrated but containing water as much as 60 wt.%. These materials are generally treated as waste or simply combusted directly to generate heat. Recently, we attempted to convert them into middle caloric gas to substitute for natural gas, as a chemical or a high-rank gaseous fuel for advanced combustion utilities. Such conversion is implemented through dual fluidized bed gasification （DFBG）. Concerning the high water content of the fuels, DFBG was suggested to accomplish either with high-efficiency fuel drying in advance or direct decoupling of fuel drying/pyrolysis from char gasification and tar/hydrocarbon reforming. Along with fuel drying, calcium-based catalyst can be impregnated into the fuel, without much additional cost, to increase the fuel＇s gasification reactivity and to reduce tar formation. This article reports the Ca impregnation method and its resulting effects on gasification reactivity and tar suppression ability. Meanwhile, the principle of directly gasifying wet fuel with decoupled dual fluidized bed gasification （D-DFBG） is also highlighted.
Activated carbon was employed as the adsorption carrier for the metal ions in HCl solution of red mud, a solid waste produced in alumina industry. To improve the adsorption capacity to valuable metal ions, the activat...
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Activated carbon was employed as the adsorption carrier for the metal ions in HCl solution of red mud, a solid waste produced in alumina industry. To improve the adsorption capacity to valuable metal ions, the activated carbon was modified by chemicals including HNO3, H2O2, H2SO4, H3PO4, NH3, Na2CO3, and tri-butyl phosphate (TBP). It was found that the modifications contributed the high adsorption capacity to almost all metal ions we focused on. In the case of TBP, remarkably higher adsorption capacity and selectivity of Sc3+ was observed. The correlation between the surface areas, IR spectra of those chemically modified activated carbons and adsorption was schemed.
At present,the research on high-order accurate finite-difference time-domain (FDTD) method for the solution of Maxwell's equations is very *** example,an explicit fourth-order staggered FDTD method is proposed ***...
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ZnO nanoparticles were synthesized by esterification reaction between zinc acetate and absolute ethanol under solvothermal conditions. The influences of reaction parameters and different surfactants on the size and mo...
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