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1.
n-Hexane andn-nonane were reacted on Pt black, 6% Pt/SiO2, 0.8% Pt/KL zeolite and a 0.6% industrial Pt/Al2O3 catalyst. Selectivities were compared at ∼10% conversion. After reaction, the catalyst was exposed to H2 and the hydrocarbons leaving the catalysts were analyzed. The amount of hydrocarbons left the catalysts decreased in the
sequence Pt black>Pt/SiO2>Pt/KL>Pt/Al2O3. The composition of removed hydrocarbons gave important—although indirect—information on the possible state of “hydrocarbonaceous
deposits” during catalysis. 相似文献
2.
The effect of H2S on the activity and selectivity of catalysts (Ru/Al2O3, Pd/Al2O3 and Ru and Pd promoted molydena-alumina) was different (on differnt catalysts and different conversions of cyclohexene). Ru-containing catalysts showed higher sulfur sensitivities than the Pd-containing ones. The sequence of catalysts by their H2S uptake related to mass of catalyst was PdMo/Al2O3RuMo/Al2O3Mo/Al2O3>Pd/Al2O3Ru/Al2O3. 相似文献
3.
Trent D Lund Timothy W West Lilyan Y Tian Lihong H Bu Daniel L Simmons Kenneth DR Setchell Herman Adlercreutz Edwin D Lephart 《BMC neuroscience》2001,2(1):20-13
Background
In learning and memory tasks, requiring visual spatial memory (VSM), males exhibit superior performance to females (a difference attributed to the hormonal influence of estrogen). This study examined the influence of phytoestrogens (estrogen-like plant compounds) on VSM, utilizing radial arm-maze methods to examine varying aspects of memory. Additionally, brain phytoestrogen, calbindin (CALB), and cyclooxygenase-2 (COX-2) levels were determined. 相似文献4.
5.
The molecular mechanics-based importance sampling function (MMBIF) algorithm [R. Iftimie, D. Salahub, D. Wei, and J. Schofield, J. Chem. Phys. 113, 4852 (2000)] is extended to incorporate semiempirical electronic structure methods in the secondary Markov chain, creating a fully quantum mechanical Monte Carlo sampling method for simulations of reactive chemical systems which, unlike the MMBIF algorithm, does not require the generation of a system-specific force field. The algorithm is applied to calculating the potential of mean force for the isomerization reaction of HCN using thermodynamic integration. Constraints are implemented in the sampling using a modification of the SHAKE algorithm, including that of a fixed, arbitrary reaction coordinate. Simulation results show that sampling efficiency with the semiempirical secondary potential is often comparable in quality to force fields constructed using the methods suggested in the original MMBIF work. The semiempirical based importance sampling method presented here is a useful alternative to MMBIF sampling as it can be applied to systems for which no suitable MM force field can be constructed. 相似文献
6.
Catalytic properties of amorphous and various crystalline (-type) zirconium phosphates have been investigated. The catalytic activity of the samples depends to a considerable extent on the quantity of (strong) acidic groups of the given material. 相似文献
7.
DR.G. Domairry A. Mohsenzadeh M. Famouri 《Communications in Nonlinear Science & Numerical Simulation》2009,14(1):85-95
In this paper Jeffery–Hamel flow has been studied and its nonlinear ordinary differential equation has been solved through homotopy analysis method (HAM). The obtained solution in comparison with the numerical ones represents a remarkable accuracy. The results also indicate that HAM can provide us with a convenient way to control and adjust the convergence region. 相似文献
8.
9.
Crystal Blake Kimberly M Fabick Kenneth DR Setchell Trent D Lund Edwin D Lephart 《BMC neuroscience》2011,12(1):28
Background
Soy-derived isoflavones potentially protect against obesity and depression. In five different studies we examined the influence of soy-containing diets or equol injections on depression, serotonin levels, body weight gain (BW) and white adipose tissue (WAT) deposition in female Long-Evans rats at various stages of life [rats were intact, ovariectomized or experienced natural ovarian failure (NOF)]. 相似文献10.
Pt(CH3)3Cl complex has been applied for preparation of highly dispersed Pt/SiO2 catalyst. Iron in different forms was used as second component for PtFe/SiO2 catalyst. Dispersity of Pt is comparable to that obtained via Pt(NH3)
4
2+
exchange. Catalytic activity and isomerization are explained in terms of Fe blocking of the surface.
Pt(CH3)3Cl Pt/SiO2. PtFe/SiO2. Pt(NH3) 4 +2 . .相似文献