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151.
Molecular Diversity - The Corona virus Disease (COVID-19) is caused because of novel coronavirus (SARS-CoV-2) pathogen detected in China for the first time, and from there it spread across the...  相似文献   
152.
153.
The usefulness of fullerene modified glassy carbon electrode in mediating the reduction of cefitizoxime in solubilized system has been demonstrated. Due to the unique structure and extraordinary properties, fullerene shows higher catalytic efficiency towards cefitizoxime reduction. The kinetic parameters, electron transfer coefficient (α) and rate constant (K0) across the modified electrode are 0.37 and 0.1081/s respectively. The proposed square‐wave voltammetric method is linear over the concentration range 1.2–10.3 µg/mL. The limit of detection (LOD) is found 0.27 ng/mL. High sensitivity and selectivity together with low detection limit of the electrode response make it suitable for the determination of cefitizoxime.  相似文献   
154.
The electron paramagnetic resonance study of Cu2+-doped bis(l-asparaginato)Mg(II) is performed at room temperature. Two magnetically non-equivalent sites for Cu2+ are observed. The spin-Hamiltonian parameters evaluated by fitting spectra to the crystalline field of rhombic symmetry are as follows: g x  = 2.0420 ± 0.0002, g y  = 2.0808 ± 0.0002, g z  = 2.3600 ± 0.0002, A x  = (99 ± 2) × 10−4 cm−1, A y  = (108 ± 2) × 10−4 cm−1, A z  = (140 ± 2) × 10−4 cm−1. The ground state wave function of Cu2+ is also determined. The g-anisotropy is estimated and compared with the experimental value. Further, with the help of optical study the nature of bonding of a metal ion with different ligands in the complex is discussed.  相似文献   
155.
A simple and convenient method for the synthesis of 1‐dialkylaminocarbothioic acid S‐[(2,3‐epithio)propyl] ester was developed by the reaction of 1‐dialkylaminocarbodithioic acid‐sodium salt with 1‐chloro‐2,3‐epoxypropane in water‐methanol mixture at room temperature. An intermediate was isolated and characterized, based on which a possible mechanism was proposed.  相似文献   
156.
Ashish Garg 《Tetrahedron》2006,62(48):11240-11244
A formal total synthesis of (+)-cardiobutanolide has been accomplished from d-glucose, a readily available precursor.  相似文献   
157.
[STRUCTURE: SEE TEXT] A highly concerted strategy for the synthesis of symmetrical type-VI beta-turn mimics was formulated. A proof of concept is presented in the synthesis of a spirobicyclic peptidomimetic of Pro-Pro-Pro-NH2, compound 6. The formation of an unusual adduct that was encountered in the process also is reported. This approach is potentially general for type-VI beta-turn mimics where the i+1 and i+2 residues are identical.  相似文献   
158.
The commutativity degree of a finite group G, denoted by Pr(G), is the probability that a randomly chosen pair of elements of G commute. The object of this paper is to derive a lower bound for Pr(G) and study some of its consequences towards characterizing G.  相似文献   
159.
This paper concerns the slow viscous flow through an aggregate of concentric clusters of porous cylindrical particles with Happel boundary condition. An aggregate of clusters of porous cylindrical particles is considered as a hydro-dynamically equivalent to solid cylindrical core with concentric porous cylindrical shell. The Brinkman equation inside the porous cylindrical shell and the Stokes equation outside the porous cylindrical shell in their stream function formulations are used. The drag force acting on each porous cylindrical particle in a cell is evaluated. In certain limiting cases, drag force converges to pre-existing analytical results, such as, the drag on a porous circular cylinder and the drag on a solid cylinder in a Happel unit cell. Representative results are then discussed and presented in graphical forms. The hydrodynamic permeability of the membrane built up from porous particles is evaluated. The variation of hydrodynamic permeability with different parameters is graphically presented. Some new results are reported for flow pattern in the porous region. Being in resemblance with the model of colloid particles with a coating of porous layers due to adsorption phenomenon, results obtained through this model can be useful to study the membrane filtration process.  相似文献   
160.
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