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951.
Charinee Kaewkhonkaen 《Molecular physics》2013,111(23):3508-3517
ABSTRACTStructures of small lengths of capped (3,3), (4,4) and (5,5) single-walled carbon nanotubes (SWCNTs) and their structures decorated by Pt atom and Ptn clusters (n = 2–4) were obtained using density functional theory calculations. Binding abilities of Pt atom and Ptn clusters on the outer surface of SWCNTs at various adsorption sites were explored. Adsorptions of H2 onto Pt atom of the Pt-decorated (3,3), (4,4) and (5,5) SWCNTs were studied and their adsorption energies are reported. The thermodynamic properties and equilibrium constants for H2 adsorptions on the Pt4-decorated (3,3), (4,4) and (5,5) SWCNTs were obtained. The adsorption of H2 on the Pt atom of the Pt4/(3,3) SWCNT was found to be the most preferred reaction of which enthalpy and free energy changes at room temperature are ?46.61 and ?23.99 kcal/mol, respectively. 相似文献
952.
Abstract The expansivity of n-hexane was measured through the heat of compression up to 500 MPa in the 243–473 K temperature range. Details about the experiment are given. From the fit to our data, the pressure variation of the specific heat Cp, in the same pressure-temperature domain, is computed; good agreement is obtained with available high pressure data. 相似文献
953.
J. Nawrocki 《Chromatographia》1987,23(10):722-726
Summary A simple gas chromatographic method is presented for the determination of the quantity of the strongest adsorption sites on
an adsorbent's surface. The method consists of the blockage of the sites with quasi-irreversibly adsorbed, known amount of
a strongly interacting compound and subsequent measuring of the retention of a hydrocarbon during the presence of the blocking
compound in the column. Heterogeneity of chromatographic grade silicas is investigated with this method. 相似文献
954.
J. Nawrocki 《Chromatographia》1991,31(3-4):193-205
Summary In this second part of the review heterogeneity of the silica surface is described and evidence is presented for the existence of a low population of strong adsorption sites. Methods of detection and determination of these strongly interacting sites are discussed. The last part of the review is devoted to the suppression of unwanted adsorption activity. Methods of blockage and special methods for the preparation of HPLC packings are described. 相似文献
955.
1.INTRODUCTIONDyewastewaterisakindofseriouspollutionsource.InthetraditionaltreatmentmethodsfordyewastewatergenerallytherearefourapproachesincludingelectricchargeneutraliZationofgelparticles,complexation(chelatation),redoxreaction,andbiochemicalcoagulationII~31.Recently,dyewastewaterhasbecomemoreconcentrated,moredifficulttodegradedbiochemically,andmorepoisonous,whichbringsaboutagreatchallengeforwatertreatment.AlthoughtheCOD(chemicaloxygendemand)mayfitthequalitystandardofwastewaterdischar… 相似文献
956.
957.
Intense Raman scattering by acetophenone molecules adsorbed on colloidal silver particles is reported. Greater enhancement
is observed for the ring breathing and ring stretching vibrations. The orientation determination analysis shows that the adsorption
of acetophenone molecule is neither through its co-ordinating site nor through itsπ-orbital system and there is no strong chemical interaction. However significant intensity enhancement for several vibrations
suggests that the contribution is from classical electromagnetic field on the rough surface. 相似文献
958.
Modified semiempirical Interacting Bonds Method in the slab approximation with due regard for relaxation after free surface formation was used to calculate surface energies and heats of oxygen adsorption for various faces of hematite. The results obtained explained faceting of some faces after high-temperature annealing and formed bases for analysis of the structure sensitivity of CO oxidation reaction catalyzed by oxides with corundum-type structures. 相似文献
959.
We generalize previous stochastic classical trajectory-ghost atom calculations for describing palladium deposition onto the Ni(111) surface between 0.1 and 0.5 monolayers. The growth evolves through two-dimensional islands. The islands are formed following the downward funneling mechanism. Surface temperature does not affect the island growth. 相似文献
960.
V. V. Shelukhin 《Journal of Applied Mechanics and Technical Physics》2005,46(4):513-522
Models for the sedimentation of particles suspended in solution are proposed that take into account mass transfer between the liquid fraction of the solution and the particles. The structure and velocity of the concentration wave describing the upward extension of the zone with a high concentration of the solid phase are studied using a kinematic model with the Froude number as a small parameter. It is established that the concentration-wave velocity becomes lower if the sorption parameter is set equal to zero, i. e., if the sorption properties of the suspended particles are ignored.__________Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 46, No. 4, pp. 66–77, July–August, 2005. 相似文献