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101.
Bodige S. Ravula P. Gulipalli K. Ch. Endoori S. Cherukumalli P. Koteswara Rao Chandra J. N. Narendra Sharath Seelam N. 《Russian Journal of General Chemistry》2020,90(7):1322-1330
Russian Journal of General Chemistry - A series of novel N-{2-fluoro-6-[(4,6-dimethoxy-1,3,5-triazin-2-yl)methyl]phenyl} carboxamide derivatives has been synthesized, and their molecular structures... 相似文献
102.
103.
Based on XPS and UVPS studies, it is shown that oxygen is preferentially adsorbed molecularly in the singlet state on Cu and Ag surfaces containing presorbed chlorine. Adsorption of chlorine on Cu and Ag surfaces containing presorbed atomic oxygen causes a disappearance of the oxygen. Extended Hückel calculations predict the observed behaviour. 相似文献
104.
This paper describes a special method of laser-based deposition to synthesize palladium-ceramic composite membranes. Thin film Pd was deposited on a ceramic substrate by Nd-YAG laser irradiation of coating precursor PdCl2 on γ-alumina substrate. The parameters of the laser processing technique were optimized to synthesize metal-ceramic composite membranes. The physical and chemical characteristics of Pd coated γ-alumina membranes were studied and compared with various other alumina membranes referenced in the literature. Hydrogen permeation experiments were performed in a CO + CO2 + CH4 + H2 environment under typical catalytic steam gasifier exit conditions. The Pd-ceramic composite showed good mechanical and thermal stability and resulted in a hydrogen permeability flux of about 0.061 mol/m2 s. The activation energy of the Pd membrane was found to be 5.39 kJ/mol in a temperature range of 900-1300 °F. 相似文献
105.
106.
The condition on the impurity potential is derived using the second Born approximation for the phase shift occurring in the Friedel sum rule. The result distinguishes between the donor-and acceptor-type scattering centers. 相似文献
107.
An expression has been derived for the temperature dependent exchange integral for a pair of interacting shallow donors substituted in a dielectric material. This has been achieved by taking into account the phonon induced mixing of excited orbital states with the ground orbital states of the impurity centres. The results have been used to explain the temperature narrowing of the EPR line width observed by some workers in phosphorus doped germanium at low temperatures. Good agreement between theory and experimental results seems to favour the proposed mechanism in preference to one of motional narrowing due to hopping. 相似文献
108.
P?ivi M?ki-Arvela Serap Sahin Narendra Kumar Jyri-Pekka Mikkola Kari Er?nen Tapio Salmi Dmitry Yu. Murzin 《Reaction Kinetics and Catalysis Letters》2008,94(2):281-288
Liquid phase tert-butylation of m-cresol was carried out using 12-tungstosilicic acid supported on neutral alumina by varying different parameters. The reaction
has also been carried out by using calcined samples under optimized conditions. The present catalyst shows an excellent activity
of 93.2%, conversion of 100% selectivity for the o-isomer, an important industrial product. 相似文献
109.
Enantioselective synthesis of γ-aryl-γ-butyrolactones is achieved using (S)-1-phenylethylamine as a chiral auxiliary. The synthesis involves cascade formation-destruction-formation of the chiral centre with a delayed stereoselective step. The actual stereoselective step has been found to be intramolecular nucleophilic attack on a diastereotopic carbocation formed, thereby resulting in the formation of non-racemic γ-aryl-γ-butyrolactones. 相似文献
110.
Diphenylphosphoryl azide (DPPA) mediated one-pot synthesis of Nα-Fmoc/Bsmoc/Boc/Z-protected ureidopeptides and peptidyl ureas as well as phenyl/succinimidyl (Nα-urethane protected) methyl carbamates starting from Nα-protected amino acids is reported. The formation of an azide, its rearrangement and coupling with an amino component is accomplished in a sequence of one-pot operations. The protocol has incorporated urea linkages in a sterically hindered peptide. 相似文献