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51.
Structural Chemistry - Enterococcus faecium MurF (EfMurF) enzyme catalyzes the addition of d-alanyl-d-alanine to form murein UDP-N-acetylmuramoyl-pentapeptide. This is the last cytoplasmic step of... 相似文献
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A few kinds of novel Schiff base complexes have been prepared by three component reaction of the substituted hydroxyacetophenone with several aliphatic diamines and transition metals such as; Ni(II), Zn(II) and UO2(II) under mild reaction conditions. The products have been afforded with excellent yields and appropriate reaction times. The structure of these ligands has been characterized by their IR, 1H NMR, 13C NMR and MS spectral and physical data. 相似文献
57.
Electrical properties of SiO2 grown on the Si-face of the epitaxial 4H-SiC substrate by wet thermal oxidation technique have been experimentally investigated
in metal oxide-silicon carbide (MOSiC) structure with varying oxide thicknesses employing Poole-Frenkel (P-F) conduction mechanism.
The quality of SiO2 with increasing thickness in MOSiC structure has been analysed on the basis of variation in multiple oxide traps due to effective
P-F conduction range. Validity of Poole-Frenkel conduction is established quantitatively employing electric field and the
oxide thickness using forward I–V characteristics across MOSiC structures. From P-F conduction plot (ln(J/E) vs. E
1/2), it is revealed that Poole-Frenkel conduction retains its validation after a fixed electric field range. The experimental
methodology adopted is useful for the characterization of oxide films grown on 4H-SiC substrate. 相似文献
58.
Ali Akbar Ashkarran Azam Iraji?zad Seyed Mohammad Mahdavi Mohammad Mahdi Ahadian 《Applied Physics A: Materials Science & Processing》2010,100(4):1097-1102
ZnO nanostructures were synthesized through arc discharge of zinc electrodes in deionized (DI) water. X-ray diffraction (XRD)
analysis of the prepared nanostructures indicates formation of crystalline ZnO of hexagonal lattice structures. Transmission
electron microscopy (TEM) images illustrate rod-like as well as semi spherical ZnO nanoparticles with 15–20 nm diameter range,
which were formed during the discharge process with 5 A arc current. The average particle size was found to increase with
the increasing arc current. X-ray photoelectron spectroscopy (XPS) analysis confirms formation of ZnO at the surface of the
nanoparticles. Surface area of the sample prepared at 5 A arc current, measured by BET analysis, was 34 m2/g. Photodegradation of Rhodamine B (Rh. B) shows that the prepared samples at lower currents have a higher photocatalytic
activity due to larger surface area and smaller particle size. 相似文献
59.
Mahmood Z Azam M Mushtaq A Kausar R Kausar S Gilani SR 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,65(2):445-452
The infrared spectra of pure Mn(CO)(5)X in the region 4000-400 cm(-1) has been obtained in the vapour phase. The observed spectrum has been analyzed to distinguish the fundamental frequencies, the rotational-vibrational and structure, and overtone and combination frequencies. The assignment of the observed vapour phase frequencies to the fundamental modes of vibration has been made on C(4V) symmetry. The weak peaks due to XMn(CO)(4)((13)CO) molecules have been measured and assigned for all molecules. This study provides a comprehensive comparison of these compounds, with all of these data the assignment of frequencies is reviewed and a set of quite unambiguous assignments made. The significant finding in this regards are that, it is not necessary to assume lower than C(4V) symmetry for XMn(CO)(5) as has been done in previous consideration of some infrared spectrum of these compounds. 相似文献
60.
Warped product manifolds are known to have applications in physics. For instance, they provide an excellent setting to model space-time near a black hole or a massive star (cf. [9]). The studies on warped product manifolds with extrinsic geometric point of view were intensified after the B.Y. Chen's work on CR-warped product submanifolds of Kaehler manifolds (cf. [6], [7]). Later on, similar studies were carried out in the setting of l.c.K. manifolds and nearly Kaehler manifolds (cf. [3], [11]). In the present article, we investigate a larger class of warped product submanifolds of l.c.K. manifolds, ensure their existence by constructing an example of such manifolds and obtain some important properties of these submanifolds. With regard to the CR-warped product submanifold, a special case of generic warped product submanifolds, we obtain a characterization under which a CR-submanifold is reducesd to a CR-warped product submanifold. 相似文献