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991.
In this paper, we approximate the integration of continuous fuzzy real number valued function of one and two variables. To do this, we use Bernstein-type fuzzy polynomials. Moreover, we obtain the error estimates for these approximations in terms of the modulus of continuity. 相似文献
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Shahed Hassanpoor Gholamreza Khayatian Amir Reza Judy Azar 《Mikrochimica acta》2015,182(11-12):1957-1965
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Experimental Investigation on Upgrading of Lignin‐Derived Bio‐Oils: Kinetic Analysis of Anisole Conversion on Sulfided CoMo/Al2O3 Catalyst 下载免费PDF全文
Hamid Reza Rahimpour Majid Saidi Parisa Rostami Bruce C. Gates Mohammad Reza Rahimpour 《国际化学动力学杂志》2016,48(11):702-713
Kinetics of the hydroprocessing of anisole, a compound representative of lignin‐derived bio‐oils, catalyzed by a commercial sulfided CoMo/Al2O3, was determined at 8–20 bar pressure and 573–673 K with a once‐through flow reactor. The catalyst was sulfided in an atmosphere of H2 + H2S prior to the measurement of its performance. Selectivity‐conversion data were used as a basis for determining an approximate, partially quantified reaction network showing that hydrodeoxygenation (HDO), hydrogenolysis, and alkylation reactions take place simultaneously. The data indicate that these reactions can be stopped at the point where HDO is virtually completed and hydrogenation reactions (and thus H2 consumption) are minimized. Phenol was the major product of the reactions, with direct deoxygenation of anisole to give benzene being kinetically almost insignificant under our conditions. We infer that the scission of the Cmethyl–O bond is more facile than the scission of the Caromatic–O bond, so that the HDO of anisole likely proceeds substantially through the reactive intermediate phenol to give transalkylation products such as 2‐methylphenol. The data determine rates of formation of the major primary products. The data show that if oxygen removal is the main processing goal, higher temperatures and lower pressures are favored. 相似文献
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We have applied DFT calculations to devise some (SiH)48X12 heterofullerenes with replacing of 12 Si–H units with a series of the group III and V dopants, P, N, As, B, Al and Ga, with the configuration of one dopant per pentagonal ring. Our results indicate that binding energies of heterofullerenes with group III dopants are smaller than those of heterfullerenes with group V dopants. Density of state obtained for the systems indicate a distinct change near the valence level compared to that of Si60H60, and a local energy level appears after the doping. (SiH)48X12 heterofullerenes with the group III and V dopants are composed of positively and negatively charged dopant atoms, each of which is surrounded by opposite charged Si atoms. The electrophilicity values of (SiH)48X12 heterofullerenes, except for (SiH)48N12, are greater than that of their parent. Because of the higher electronegativity of group V elements and electron transfer from the cages to the group V dopants, electrophilicity values for the (SiH)48X12 heterofullerenes with the group V dopants are always smaller than those of heterofullerenes with the group III dopants. 相似文献