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61.
Eckhard Spohr Andrij Trokhymchuk Douglas Henderson 《Journal of Electroanalytical Chemistry》1998,450(2):211
We report molecular dynamics (MD) simulations on the adsorption of water in attractive and repulsive slit pores, where the slit and a bulk region are in contact with each other. Water structure, surface force and adsorption behavior are investigated as a function of the overall density in the bulk region. The gas–liquid transition in both types of pores occurs at similar densities of the bulk region. 相似文献
62.
Piotr Kutrowski Dominika Sukowska Renata Pytlowany Roman Dziembaj 《Reaction Kinetics and Catalysis Letters》2004,81(1):3-11
Catalytic performance of Ba(OH)2 and Sr(OH)2 in self-condensation of acetone was examined in the temperature range from 273 to 303 K. A kinetic model of second order with respect to acetone was used for interpretation of the results obtained for the diacetone alcohol formation.This revised version was published online in December 2005 with corrections to the Cover Date. 相似文献
63.
64.
Takao Masuda 《Catalysis Surveys from Asia》2003,7(2-3):133-144
The diffusion mechanisms within zeolite catalysts, such as resistance to diffusion at pore mouths, configurational diffusion, adsorption-controlled diffusion, influence of co-existing molecules and pore blocking, were overviewed. Two kinds of diffusivities, the intracrystalline diffusivity and the effective diffusivity, were discussed separately to clarify the diffusion mechanism. 相似文献
65.
66.
Simple and rapid micellar electrokinetic capillary chromatographic method for simultaneous determination of four antiepileptics in human serum 总被引:1,自引:0,他引:1
A very rapid and simple MEKC method was developed for the simultaneous determination of four antiepileptic drugs, ethosuximide (Etho), primidone (Pri), phenytoin (Pht) and carbamazepine (Cbz) in human serum. Sample analysis required only 100 microL of human serum which only needed to be centrifuged, decanted and combined with the running buffer [5.3 mM Na(2)HPO(4)/3.2 mM borax buffer (pH 9.5) containing 55 mM SDS and 3.5% (v/v) acetone]. The analysis was performed in only 10 min into fused-silica capillaries (57 cm total length with 50 microm i.d. and 50 cm to the detector) using the MEKC methodology with diode-array detection at 220 nm. The calibration graphs were established for ethoximide, primidone, phenytoin and carbamazepine between 0 and 20 mg/L. Recoveries were between 85 and 87%. The simplicity of the proposed methodology makes it suitable for routine clinical use, especially for epileptic patients on polytherapy. 相似文献
67.
应用火焰原子吸收光谱(FAAS)法测定了钮扣电池中铅和镉的含量,对测定条件作了较详细的研究。用在线双毛细管标准加入法消除了基体的干扰。按所述方法测定电池样品中铅和镉,测定结果的RSD依次为3.58%和5.87%,铅和镉的浓度水平分别为5.4×10-3%和2.3×10-4%(质量分数),回收率结果为93.0%~100.1%(铅)和95.0%~101.0%(镉)。 相似文献
68.
Varughese M. Alexander 《Tetrahedron letters》2005,46(40):6957-6959
Bismuth(III) nitrate pentahydrate is found to be an efficient catalyst for the Pechmann condensation reaction of phenols and β-ketoesters under solvent-free conditions. The reaction protocol is simple and is followed by aqueous work-up leading to the formation of the corresponding coumarin derivatives in good yield and high purity. 相似文献
69.
Condensation of propanal with cyanothioacetamide and morpholine gave 3-cyano-4-ethyl-5-methyl-6-morpholino-2-piperidone, the
structure of which was studied by X-ray analysis. Reaction of propanal with cyanothioacetamides and cycloalkanone enamines
gave 3-cyano-4-ethyl-2,5,6,7-tetrahydropyrindin-2(1H)-one and 3-cyano-4-ethyl-5,6-hexamethylenepyridine-2(1H)-thione. The
latter was used for the preparation of substituted 2-benzyloxycarbonylmethylthiopyridine and 3-amino-2-benzyloxycarbonylthieno[2,3-b]pyridine.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1053–1059, July, 2005. 相似文献
70.