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91.
92.
A number of novel 2,3,4,5-tetrahydro[1,3]diazepino[1,2-a]benzimidazole derivatives 2 were obtained by alkylation mainly in the 1H-tautomeric form of 2,3,4,5-tetrahydro[1,3]diazepino[1,2-a]benzimidazole or its 8,9-dimethyl-substituted analog 4-chlorobenzyl bromide, 4-chloroacetic acid fluoroanilide, and 4-tert-butylphenacyl bromide in neutral medium. Compounds 3 were cyclized and synthesized earlier with 11-phenacyl-substituted diazepino[1,2-a]benzimidazoles upon heating in conc. HBr. The chemical structures of the compounds were clarified by using the 1H Nuclear Magnetic Resonance Spectroscopy (1H-NMR) technique. Anxiolytic properties were evaluated using the elevated plus maze (EPM) and open field (OF) tests. The analgesic effect of compounds was estimated with the tail flick (TF) and hot plate (HP) methods. Besides, possible the influence of the test compounds on motor activities of the animals was examined by the Grid, Wire, and Rotarod tests. Compounds 2d and 3b were the most active due to their prominent analgesic and anxiolytic potentials, respectively. The results of the performed in silico analysis showed that the high anxiolytic activity of compound 3b is explained by the combination of a pronounced interaction mainly with the benzodiazepine site of the GABAA receptor with a prominent interaction with both the specific and allosteric sites of the 5-HT2A receptor.  相似文献   
93.
粗糙度对4种聚氨酯弹性体粘着性能的影响   总被引:6,自引:2,他引:6  
采用生物摩擦磨损试验台测定了4种聚氨酯的弹性模量,研究了表面粗糙度和法向力对粘着力的影响.结果表明:4种聚氨酯的弹性模量在55~1206kPa之间,粘着力由高到低的排序同其弹性模量排序相反,弹性模量较低的试样的饱和粘着力达到15kPa,且表面粗糙度对粘着力的影响不明显;弹性模量较大的试样的粘着力仅为1.5kPa,随弹性模量增加,表面粗糙度的影响增大;试样之间的接触形式同粘着力密切关系,相当于单个凸峰接触的蓝宝石球对聚氨酯试样的粘着力不受法向力的影响,而在平面接触情况下粘着力先随法向力增加而增大,当法向力超过一定(10~15kPa)值后,粘着力增加趋缓并达到饱和值.  相似文献   
94.
95.
We introduce and demonstrate a new microscopy concept: imaging interferometric microscopy (IIM), which is related to holography, synthetic-aperture imaging, and off-axis-dark-field illumination techniques. IIM is a wavelength-division multiplex approach to image formation that combines multiple images covering different spatial-frequency regions to form a composite image with a resolution much greater than that permitted by the same optical system using conventional techniques. This new type of microscopy involves both off-axis coherent illumination and reinjection of appropriate zero-order reference beams. Images demonstrate high resolution, comparable with that of a high-numerical-aperture (NA) objective, while they retain the long working distance, the large depth of field, and the large field of view of a low-NA objective. A Fourier-optics model of IIM is in good agreement with the experiment.  相似文献   
96.
Selective and independent dimerization of tri- and tetraurea derivatives was used to build up dendritic assemblies which are uniform in size and structure. Dendrimers with the total molecular masses of about 25 000 g/mol were obtained. The existence of uniform assemblies was proved by 1H and 1H DOSY NMR experiments and also by dynamic light scattering.  相似文献   
97.
98.
Tri-(2-alkoxy-5-ureido-phenyl)methanes represent a novel self-complementary motif forming hydrogen bonded homo- and heterodimers in nonpolar, aprotic solvents as evidenced by 1H NMR and ESI-mass spectra and by the formation of heterodimers. MD simulations suggest the formation of hydrogen bonds of different strength in agreement with NMR data. The dimerization does not interfere with that of tetraurea calix[4]arenes. A combination of both motifs may be used therefore to build up larger structures via self-assembly processes. [structure: see text]  相似文献   
99.
100.
Abstract

The electrical charge assosiated with dislocation motion in KCl:Ba has been studied within the interval from 77 to 292K using on indentation method. The comparison of the potential difference values at 77 and 292K was performed on condition that the impression diagonals were roughly equal. The kinetics of the potential change was studied.  相似文献   
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