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921.
Theoretical and Mathematical Physics - We describe an explicit formula for the first-order quasiderivation of an arbitrary central element of the universal enveloping algebra of a general linear... 相似文献
922.
Costa Bruno Patrcio Carpin Daniele da Silva Bambirra Alves Fillemon Edillyn Barbi Rafaela Cristina Turola de Melo Anely Maciel Ikeda Mnica Ribani Rosemary Hoffmann 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6721-6737
Journal of Thermal Analysis and Calorimetry - Extraction methods are determinant in technological properties of non-conventional starches. Different steeping procedures are capable of modifying the... 相似文献
923.
924.
Hidetsura Cho Yoshio Nishimura Hiroshi Ikeda Mitsuhiro Asakura Shinji Toyota 《Tetrahedron》2018,74(20):2405-2413
Experimental and theoretical studies on the thermodynamics and properties of 2-substituted 6(4)-methyl-1,4(1,6)-dihydropyrimidine-5-carboxylates were undertaken by 1H NMR measurements and DFT (density functional theory) calculations. The ratios of tautomers a/b of dihydropyrimidines (DPs) 1, 2, and 3 were determined under various conditions to reveal the effects of temperature, solvent, and concentration on the thermodynamic data. The observed results, the free energy differences (ΔG), enthalpy differences (ΔH), and entropy differences (ΔS), are discussed in terms of the molecular structures, dipole moments (DM), and the electrostatic potential maps calculated by the DFT to clarify the nature of the DPs. 相似文献
925.
926.
927.
Kosuke Katagiri Takashi Ikeda Atsuya Muranaka Masanobu Uchiyama Masahide Tominaga Isao Azumaya 《Tetrahedron: Asymmetry》2009,20(22):2646-2650
Novel chiral cyclic molecules composed of aromatic triamides were constructed in modest yield from 4-N-(4′-methoxybenzyl)amino-3-decyloxybenzoic acid using dichlorotriphenylphosphorane, because of the preorganized component of the tertiary benzanilide moieties. A racemic mixture of two diastereomers, syn and anti conformers of cyclic aromatic triamides, was resolved into enantiomers by HPLC using a preparative chiral column. The absolute configuration of each enantiomer in both diastereomers was determined by comparison of the time-dependent density functional theory (TD-DFT) calculated circular dichroic (CD) spectra with the experimentally derived CD spectra recorded on each sample. 相似文献
928.
2-Methylthio-4-alkenoic esters prepared from 1-alkenes and ethyl methylsulfinylacetate are converted into α,β-unsaturated esters via hydrogenation, oxidation, and thermolysis. This method was applied to the synthesis of queen substance. 相似文献
929.
K Yamada M Torimura S Kurata Y Kamagata T Kanagawa K Kano T Ikeda T Yokomaku R Kurane 《Electrophoresis》2001,22(16):3413-3417
A bacterial cell mixture ot Cellulomonas cartae KYM-7 and Agrobacterium tumefaciens KYM-8 was analyzed by capillary zone electrophoresis (CZE) and capillary gel electrophoresis (CGE). Both pherograms showed two discrete peaks. The cells in the peaks were collected, Gram stained, and examined with a microscope. The cells of the two strains were well separated by OGE, and each OGE peak consisted almost entirely of cells of one strain (greater than 98% purity), whereas each CZE peak contained cells of both strains (about 90% purity). In the concentration range of 1.0 x 10(10) to 1.0 x 10(12) cells/mL, the area of CGE peaks was proportional to the amount of cells. The growth of the two strains in mixed culture was measured by OGE. The OGE quantification data were in good agreement with those obtained using fluorescence in situ hybridization. The CGE analyses were accomplished in 1 h, using a relatively uncomplicated procedure. Thus, OGE exhibited great advantages in accuracy, rapidity, and simplicity. 相似文献
930.
The structure of 12Be is investigated using a microscopic α+α+4n model based on the molecular-orbit (MO) model. It is shown that the remark-able α-clustering and the contribution of the spin-orbit interaction make the binding of the state with the (3/2?)2(1/2+)2 configuration for the valence neutrons properly stronger in comparison with the closed p-shell (3/2?)2(1/2?)2 configuration. The molecular-like structure of the C isotopes is also investigated using a microscopic α+α+α+n+n+... model. 相似文献