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951.
952.
This work deals with spectral mapping theorems for neutron transport semigroups
in unbounded geometries and L1 setting. The mathematical analysis relies on harmonic analysis of certain measure valued mappings related to
Dyson-Phillips expansions and on some functional analytic results on the
critical spectrum. 相似文献
953.
Naz Mohammed Aghatabay Metin Tulu Yaghub Mahmiani Mehmet Somer Basaran Dulger 《Structural chemistry》2008,19(1):71-80
1,6-Bis(benzimidaz-2-yl)-3,4-dithiahexane ligand (L) and its mercury halide complexes were prepared and characterised. The
elemental analysis, molecular conductivity, FT-Raman, FT-IR (mid, far), 1H, 13C NMR and geometry optimization in MOPAC using MNDOd parameter on CACHE, prove the existence of neutral, mononuclear and the
distorted tetrahedral [Hg(L)X2] complexes. In all the three complexes, the ligand acts as a chelating bidentate, through two of the bridging sulphur atoms
and together with the monodentate coordination of the two anionic halide ligands to the metal centre forming a possible 4-coordinate
compounds. The antimicrobial activities of free ligand, its hydrochlorinated salt, mercury halides and the complexes are evaluated
using disk diffusion method in dimethyl sulfoxide (DMSO) as well as the minimal inhibitory concentration (MIC) dilution method,
against 10 bacteria. The obtained results from disk diffusion method are assessed in side-by-side comparison with those of
Penicillin-g, Ampicillin, Cefotaxime, Vancomycin, Oflaxacin and Tetracyclin well-known antibacterial agents. The results from
dilution procedure are compared with Gentamycin as antibacterial and Nystatin as antifungal. The antifungal activities are
reported on five yeast cultures namely Candida albicans, Kluyveromyces fragilis, Rhodotorula rubra, Debaryomyces hansenii and Hanseniaspora guilliermondii, and the results are referenced with Nystatin, Ketaconazole and Clotrimazole, commercial antifungal agents. In most cases,
the compounds show broad-spectrum (Gram+ & Gram− bacteria) activities that are comparatively, slightly less active or equipotent to the antibiotic and antifungal agents in
the comparison tests. 相似文献
954.
Mohammed Shahid Ali Syed Rafiuddin Mohsin Ghori Aamer Roshanali Khatri 《Chromatographia》2008,67(7-8):517-525
A simple and specific hydrophilic interaction liquid chromatography (HILIC) procedure for the quantification of metformin
hydrochloride (MFH) and its impurities in bulk pharmaceuticals and finished dosage forms has been developed. The method is
based on hydrophilic interaction of the analytes with silica. The influence of the weaker solvent, acetonitrile, pH and the
nature and ionic strength of the buffer was studied. Linearity range and percent recoveries for MFH were 100–400 μg mL−1 and 100.62%, respectively. Good validation data were obtained for all compounds. The method separates impurities cyanoguanidine
(CGD), melamine (MLN) and other degradation products with a run time of less than 13 min. Degradation studies involved thermal
stress, hydrolysis at various pHs and chemical and photolytic oxidation. 相似文献
955.
Hydrazinium ethylenediaminetetraacetatometalate complexes of the type, N2H5 [M(Hedta)·H2O] were subjected to systematic TG/DTG analysis. The decomposition process consists of three stages. Kinetic parameters were evaluated for each of these stages using the Coats-Redfern equation. 相似文献
956.
Mohammed Ibn-elhaj Antoine Skoulios Daniel Guillon Joanna Newton Philip Hodge Harry J. Coles 《Liquid crystals》1995,19(3):373-378
The phase behaviour and the structural characterization of a new series of linear dimeric and cyclic tetrameric molecules which contain three distinct parts, a cyanobiphenyl aromatic core (A), a paraffin chain (P) and a central siloxane group (B) with the A-P-B-P-A sequence, are described. Incompatible with one another, these parts tend to locate themselves in three separate sub-layers superposed in a partially bilayered smectic A structure. Each sub-layer adapts its internal structure in order to be appropriate for superposition, as in the case of organosiloxane molecules with the A-P-B sequence reported previously. 相似文献
957.
We demonstrate a simple all-fiber device that can transform a Gaussian-shaped laser beam into a uniform intensity beam. The device is based on the interaction of a core mode and a cladding mode partially coupled out by a long-period grating. We have achieved good beam uniformity (<4% intensity variation) and reduced beam divergence (1.5deg of half divergence angle) while keeping the insertion loss to 0.1 dB. The measured beam uniformity matches well with simulated results. The device can also change the beam shape from a Gaussian to a donut, to top hat, and back to a Gaussian, dynamically by tuning the laser wavelength. 相似文献
958.
Mohammed K Hossain-Ibrahim Kia Rezajooi William B Stallcup Alexander R Lieberman Patrick N Anderson 《BMC neuroscience》2007,8(1):80
Background
The chondroitin sulphate proteoglycan NG2 blocks neurite outgrowth in vitro and has been proposed as a major inhibitor of axonal regeneration in the CNS. Although a substantial body of evidence underpins this hypothesis, it is challenged by recent findings including strong expression of NG2 in regenerating peripheral nerve. 相似文献959.
In the present work, beech wood condensates are separated from the aqueous phase. Experimental results reveal an electrostatic interaction between the oppositely charged wood extracts after oxidation and Ca(OH)(2). The increase in aqueous phase pH resulted in enhanced removal of wood extracts from water. The polarographic assays were carried out at 25 degrees C using a Gilson oxygraph equipped with a Clark electrode in order to determine the oxygen uptake during the oxidation reaction. The effect of pH is explained based on oxygen uptake. The organic compounds found in the aqueous effluent are responsible for the brown color. The objective of this study is to find the optimum pH to eliminate the wood extracts from the liquid effluents. 相似文献
960.
Viatcheslav V. Kolmychkov Olga S. Mazhorova Yurii P. Popov Patrick Bontoux Mohammed El Ganaoui 《Comptes Rendus Mecanique》2005,333(10):739-745
Three-dimensional calculations have been done to simulate the onset of convective motion in ternary nondilute solution under phase transition conditions. The process is considered for Rayleigh number in the range , where subcritical convective motion with hexagonal flow pattern is identified. The results are in good agreement with the linear and finite amplitude theory of hydrodynamics instability. To cite this article: V.V. Kolmychkov et al., C. R. Mecanique 333 (2005). 相似文献