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241.
Virendra V. Singh Pushpendra K. Sharma Anchal Shrivastava Pranav K. Gutch Kumaran Ganesan Mannan Boopathi 《Electroanalysis》2020,32(8):1671-1680
The threat from chemical warfare agents (CWAs) imparts an alarming call for the global community not limited to human being but also extends as unprecedented environmental threat, hence, timely detection and degradation in the event of CWAs attack is very crucial. Herein, we describe a hybrid material of 3‐aminopropyltriethoxysilane (APTES) modified graphene oxide (GO) on glassy carbon (GC) electrode along with electrodeposited silver nanodendrimers (AgNDs) for the electrochemical detection and degradation of CWA sulphur mustard (HD). The AgNDs/APTES‐GO hybrid material was characterized by SEM, EDX, BET, TGA, Raman, UV‐Vis, XPS and XRD techniques. The AgNDs/APTES‐GO modified GC electrode was also characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Electrochemical studies indicated presence of electrocatalysis owing to the synergistic effect of AgNDs and GO for sensing CWA HD via reductive dehalogenation. The AgNDs/APTES‐GO modified GC electrode exhibited linearity for CWA HD from 5.3 μM to 42.4 μM. Constant potential electrolysis was performed with modified electrode and degradation products were analysed using GC‐MS, highlighting the great potential of graphene based hybrid material. This new strategy provides an opportunity for the development of “detect and destroy” system for the CWAs and other environmental toxic pollutant, which could help in mitigation of on‐ site events for first responders. 相似文献
242.
S. Shrivastava 《Solid State Communications》2011,151(10):775-777
Thin films of 1,4-trans-polyisoprene have been prepared on various substrates from toluene solution and characterized using Fourier transform infrared (FTIR) spectroscopy, optical absorption spectroscopy and X-ray diffraction before and after doping with iodine. The optical absorption spectrum at low doping shows two peaks: one at 4.2 eV and the other at 3.2 eV. X-ray diffraction indicates an increase of (111) and (122) peak intensities upon doping. Quadratic electro-optic measurements have been made using field-induced birefringence. The Kerr coefficients as measured (3.5×10−10 m/V 2 at 633 nm and 2.5×10−10 m/V 2 at 1.55 μm) are exceptionally large, and they have been attributed to the subnanometer-size metallic domains formed upon doping and charge transfer. 相似文献
243.
Sushant Gupta Purushottam KumarA. Arul Chakkaravathi Doina CraciunRajiv K. Singh 《Applied Surface Science》2011,257(13):5837-5843
Zinc oxide has become an important material for various applications. Commercially available zinc oxide single crystals and as-grown zinc oxide thin films have high surface roughness which has detrimental effects on the growth of subsequent layers and device performance. A chemical mechanical polishing (CMP) process was developed for the polishing of zinc oxide polycrystalline thin films. Highly smooth surfaces with RMS roughness <6 Å (as compared to the initial roughness of 26 ± 6 Å) were obtained under optimized conditions with removal rates as high as 670 Å/min. Effects of various CMP parameters on removal rate and surface roughness were evaluated. The role of pH on the polishing characteristics was investigated in detail. 相似文献
244.
Parasar Mohanty Saurabh Shrivastava 《Journal of Mathematical Analysis and Applications》2011,382(1):334-338
In this paper we obtain a bilinear analogue of Fefferman-Stein?s vector valued inequality for classical Hardy-Littlewood maximal function. Also, we prove the boundedness of bilinear Hardy-Littlewood maximal operator from Lp1(Rn)×Lp2(Rn)→L1(Rn), where , by applying the method of rotations. 相似文献
245.
Lori A. Emert-Sedlak Purushottam Narute Sherry T. Shu Jerrod A. Poe Haibin Shi Naveena Yanamala John Jeff Alvarado John S. Lazo Joanne I. Yeh Paul A. Johnston Thomas E. Smithgall 《Chemistry & biology》2013,20(1):82-91
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246.
A reverse ortho effect is observed for the (13)C NMR chemical shifts of the carboxyl carbon (δ(co)) in benzoic acids measured in aprotic solvents of varying polarity. The ortho effect on δ(co) is best described by a combination of the reverse field and steric accelerating effects of the substituent in an 80: 20 pattern in apolar aprotic solvents and a 60: 40 pattern in dipolar aprotic ones. Interestingly, no good enough correlation was found between δ(co) and log k(1) of the acids measured in similar solvents. A critical analysis of the results clearly indicates the use of an apolar aprotic solvent and not a dipolar aprotic one as the solvent of choice for investigating intrinsic substituent effects on δ(c) in an aromatic system. 相似文献
247.
In this paper, simple relations are proposed for the calculation of Debye temperature θD and melting point Tmof II‐VI and III‐V zincblende semiconductors. Six relations are proposed to calculate the value of θD. Out of these six relations, two are based on plasmon energy data and the others on molecular weight, melting point, ionicity and energy gap. Three simple relations are proposed to calculate the value of Tm. They are based on plasmon energy, molecular weight and ionicity of the semiconductors. The average percentage deviation of all nine equations was calculated. In all cases, except one, it was estimated between 3.34 to 17.42 % for θD and between 2.37 to 10.45 % for Tm. However, in earlier correlations, it was reported between 10.59 to 33.38% for θD and 6.96 to 14.95% for Tm. The lower percentage deviation shows a significant improvement over the empirical relations proposed by earlier workers. The calculated values of θD and Tm from all equations are in good agreement with the available experimental values and the values reported by different workers. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献