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31.
Poly (N-vinyl pyrrolidone) (PVP) and ammonium thiocyanate (NH4SCN) based polymer films with different compositions have been prepared by solution casting technique. The amorphous nature of the polymer electrolytes has been confirmed by XRD analysis. The FTIR analysis confirms the complex formation of the polymer with the salt. The conductivity analysis shows that the 20 mol% ammonium thiocyanate doped polymer electrolyte has high ionic conductivity and it has been found to be 1.7 × 10−4 S cm−1, at room temperature. From the admittance plot, the activation energy has been found to be low for 20 mol% salt doped polymer electrolyte. The dielectric behavior has been analyzed using dielectric permittivity (ε), dissipation factor (tan δ) and electric modulus (M) of the samples.  相似文献   
32.
Nanoscience is a multidisciplinary skill with elucidated nanoscale particles and their advantages in applications to various fields. Owing to their economical synthesis, biocompatible nature, and widespread biomedical and environmental applications, the green synthesis of metal nanoparticles using medicinal plants has become a potential research area in biomedical research and functional food formulations. Gynostemma pentaphyllum (GP) has been extensively used in traditional Chinese medicine to cure several diseases, including diabetes mellitus (DM). This is the first study in which we examined the efficacy of G. pentaphyllum gold nanoparticles (GP-AuNPs) against obesity and related inflammation. GP extract was used as a capping agent to reduce Au2+ to Au0 to form stable gold nanoparticles. The nanoparticles were characterized by using UV–VIS spectroscopy, and TEM images were used to analyze morphology. In contrast, the existence of the functional group was measured using FTIR, and size and shape were examined using XRD analysis. In vitro analysis on GP-AuNPs was nontoxic to RAW 264.7 cells and 3T3-L1 cells up to a specific concentration. It significantly decreased lipid accumulation in 3T3-L1 obese and reduced NO production in Raw 264.7 macrophage cells. The significant adipogenic genes PPARγ and CEPBα and a major pro-inflammatory cytokine TNF-α expression were quantified using RT-PCR. The GP-AuNPs decreased the face of these genes remarkably, revealing the antiadipogenic and anti-inflammatory activity of our synthesized GP-AuNPs. This study represents thorough research on the antiobesity effect of Gynostemma pentaphyllum gold nanoparticles synthesized using a green approach and the efficacy instead of related inflammatory responses.  相似文献   
33.
Intramolecular atropselective aza Paternò–Büchi reaction involving atropisomeric enamide and imine functionalities under sensitized irradiation leads to azetidine products in good yield and selectivity (ee >96 %). A mechanistic model based on detailed photophysical and isomerization kinetic studies is provided that shed light into the reactivity of enamides leading to aza Paternò–Büchi reaction.  相似文献   
34.
A simple and efficient protocol has been demonstrated for the preparation of densely functionalized 3-aroylimidazo[1,2-a]pyridines from 2-aminopyridines and chalcones using RuCl3·H2O/I2 catalytic system. The advantages, such as low catalyst loading, broad substrate scope with respect to substitutions on aminopyridines as well as chalcones, stability of heterocycles such as thiophene under the reaction conditions, operationally simple procedure and higher yields makes this approach remarkable for synthetic applications.  相似文献   
35.
This paper investigates the three-dimensional flow of a Sisko fluid over a bidirectional stretching sheet, in a porous medium. By using the effect of Cattaneo-Christov heat flux model, heat transfer analysis is illustrated. Using similarity transformation the governing partial differential equations are transferred into a system of ordinary differential equations that are solved numerically by applying Nachtsheim-Swigert shooting iteration technique along with the 6-th order Runge-Kutta integration scheme. The effect of various physical parameters such as Sisko fluid, ratio parameter,thermal conductivity, porous medium, radiation parameter, Brownian motion, thermophoresis, Prandtl number, and Lewis number are graphically represented.  相似文献   
36.
37.
Cells have a net negative outer charge which gives rise to a potential difference in a potentiometric set up. Here, Triton X‐100 was used as a model toxin and the cell death was monitored by the potential change, noticed as decrease in negativity. Hence, cytotoxicity can be tested in vitro and real‐time using potentiometry. However, silver ions (Ag+) and/or silver chloride ions (AgCl2)?1 lead to cell death when we used the standard Ag/AgCl reference electrode with 3 M NaCl as filling solution. Our further experimentation showed that PBS as filling solution was biocompatible and also gave stable potentiometric profiles.  相似文献   
38.
Searching with a beady eye: A high-throughput, on-bead screen of rhodium metallopeptide catalysts was developed in a 96-well format for asymmetric cyclopropanation. Different sequences of natural L-amino acids have been identified that produce opposite product enantiomers. In addition to styrene derivatives, high enantioselectivity is observed for vinyl ether and vinyl amine derivatives.  相似文献   
39.
The standard enthalpy of formation, δfHo, of2 II CH has been determined at converged levels of ab initio electronic structure theory, including high order coupled cluster and full configuration interaction benchmarks. The atomic Gaussian basis sets employed include the (aug)-cc-p(C)VXZ family with X = 3, 4, 5 and 6. Extrapolations to the complete one-particle basis set and the full configuration interaction limits, where appropriate, have been performed to reduce remaining computational errors. Additional improvements in the enthalpy of formation of 2II CH were achieved by appending the valence-only treatment with core-valence correlation, relativistic effects including spin-orbit correlation, and the diagonal Born-Oppenheimer correction. The recommended values for δfHo 0 and δAf H o 298 of 2II CH are 592.48+0.47 ?0.56 kJ mol?1 and 595.93 +0.47 ?0.56 kJ mol?1, respectively.  相似文献   
40.
AK Jain  CS Shastry 《Pramana》1977,9(3):311-320
The behaviour ofS-matrix for potentials generating bound states in continuum in the neighbourhood of the positive bound state energies is studied. It is shown that unlike the case of usual negative energy bound states, theS-matrix does not have a pole at the positive bound state energy but becomes unity at the energy corresponding to bound states in continuum. Calculations ofS-waveS-matrix for a local potential constructed by Stillinger and Herrick and a separable nonlocal potential constructed by the present authors verify these results. Our results indicate that the bound states embedded in continuum constructedvia the von Neumann and Wigner procedure cannot be interpreted as resonances with zero width.  相似文献   
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