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11.
Shaikh Mohd Rizwan Uddin Loan Sajad A. Alharbi Abdullah G. 《Journal of Computational Electronics》2021,20(6):2360-2368
Journal of Computational Electronics - In this work, a Schottky junction on the drain side employing low workfunction (WF) metal is proposed as a method to suppress the OFF-state leakage in... 相似文献
12.
We have prepared Schiff base adducts of the core aldehydes of phosphatidylcholine and aminophospholipids, free amino acids,
and myoglobin. The Schiff bases of the ethanolamine and serine glycerophospholipids were obtained by reacting sn-1-palmitoyl(stearoyl)-2-[9-oxo]nonanoyl-glycerophosphocholine (PC-Ald) with a twofold excess of the aminophospholipid in
chloroform/methanol 2∶1 (vol/vol) for 18 h at room temperature. The Schiff bases of the amino acids and myoglobin were obtained
by reacting the aldehyde with an excess of isoleucine, valine, lysine, methyl ester lysine and myoglobin in aqueous methanol
for 18 h at room temperature. Prior to isolation, the Schiff bases were reduced with sodium cyanoborohydride in methanol for
30 min at 4°C. The reaction products were characterized by normal-phase high-performance liquid chromatography and on-line
mass spectrometry with electrospray ionization. The amino acids and aminophospholipids yielded single adducts. A double adduct
was obtained for myoglobin, which theoretically could have accepted up to 23 PC-Ald groups. The yields of the products ranged
from 12 to 44% for the aminophospholipids and from 15–57% for the amino acids, while the Schiff base of the myoglobin was
estimated at 5% level. The new compounds are used as reference standards for the detection of high molecular weight Schiff
bases in lipid extracts of natural products.
Based on presentation at the AOCS Annual Meeting & Expo in Indianapolis, Indiana, April 28–May 1, 1996. 相似文献
13.
14.
C. V. Jagtap V. S. Kadam T. T. Ghogare Y. A. Inamdar A. A. Shaikh R. S. Mane A. V. Shaikh 《Journal of Materials Science: Materials in Electronics》2016,27(12):12335-12339
The chemical synthesis of pristine and cadmium-doped ZnO powders using a simple, cost-effective at 65 °C is reported and characterized for their structures, optical and morphological studies using X-ray diffraction, UV–visible–Near Infra-Red (UV–Vis–NIR) spectroscopy, scanning electron microscopy measurement techniques where XRD spectra confirm the formation of ZnO and Cd-doped ZnO with hexagonal crystal structure. The particle size of ZnO is reduced on Cd-doping from 16 to 14 nm. Plane-view surface morphology analysis supported for spherical-type crystallites and UV–Vis–NIR spectra reveal shift in the band edge of ZnO after Cd-doping. Photo-degradation study of Methylene Blue dye shows Pristine ZnO degrades dye faster than Cd-doped ZnO. 相似文献
15.
Fructose-2,6-bisphosphatase (FBPase-2) is a switch between gluconeogenesis and glycolysis in the hepatic cells. The structural features required for inhibitory activity of FBPase-2 were unidentified; no leads are available for inhibiting this important enzyme. In this paper pharmacophore mapping, molecular docking methods were employed in a virtual screening strategy to identify leads for FBPase-2. A receptor based pharmacophore map was modeled which comprised of important interactions as observed in co-crystal of rat liver isozyme with the product inhibitor fructose-6-phosphate. The pharmacophore model was validated against two databases of best docked structural analogues of fructose-2,6-bisphosphate and fructose-6-phosphate. The query generated was submitted for flexible search of ligands in chemical databases, namely LeadQuest, Maybridge and NCI. The hits obtained were further screened by molecular docking using FlexX. 相似文献
16.
Rakibul Hasan Sagor Kh. Arif Shahriar Md. Ghulam Saber Md. Mahamudun Arif Joy Ikramul Hasan Sohel 《SILICON》2016,8(2):251-275
A nonlinear optimization algorithm based on the Nelder Mead method is used to characterize the frequency dependent permittivity of 15 materials based on Lorentz, modified Lorentz, Drude and Lorentz-Drude models. The optimized model parameters are used to calculate the complex relative permittivity of each material and compare it with experimental data. In each case, a very good match is found between the optimized and experimental data over a long wavelength range. Comparative study of the models used for each material is performed based on accuracy, wavelength range of applicability and computational efficiency. The parameters presented can be used for computer simulation of electromagnetic wave phenomena involving these materials. 相似文献
17.
Zwitterion (Z) monomer 3‐[diallyl{3‐(diethoxyphosphoryl)propyl}ammonio]propane‐1‐sulfonate underwent cyclocopolymerization with sulfur dioxide to give a new alternating copolymer poly(Z‐alt‐SO2) in excellent yield (ca 90%). The polyzwitterion (±) (PZ) (i.e. poly(Z‐alt‐SO2), bearing a diethylphosphonate as well as a sulfonate functionality in each repeat unit, upon ester hydrolysis gave its corresponding pH‐responsive polyzwitterionic acid (±) (PZA). The pH‐induced equilibrations (+) cationic polyelectrolyte ? (±) PZA ? polyzwitterion/anion (± ?) (PZAN) ? polyzwitterion/dianion (± =) (PZDAN) permitted us to examine the effects of charge types and their densities on the interesting solubility and viscosity behaviours. The apparent protonation constants of the basic functionalities &tbond;N±PO32? in (± =) PZDAN and &tbond;N±PO3H1? in (± ?) PZAN in salt‐free water and 0.1 mol L?1 NaCl were determined using potentiometric titrations. (±) PZA at a meagre concentration of 20 ppm was found to be an effective antiscalant to inhibit the precipitation of CaSO4 from its supersaturated solution: after 500 and 800 min, the respective scale inhibitions of 86 and 98% indicated its potential use as an effective antiscalant in reverse osmosis plant. © 2014 Society of Chemical Industry 相似文献
18.
Sanjeev V. Moharil Bhagyashree S. NagrareShabana P.S. Shaikh 《International Journal of Hydrogen Energy》2012
Ba0.5Sr0.5Co0.6Fe0.4O3−δ(BSCF5564) was synthesized by nitric acid aided EDTA–citric acid complexing sol-gel method (NECC). Both, the phase formation temperature and time of BSCF5564 synthesized NECC were found to be low i.e. single perovskite phase formation temperature is 200 °C less as compared to the conventional method of synthesis. The orthorhombic perovskite structure has been formed after calcination at 800 °C for 5 h. Scanning electron microscopy reveals the formation of porous material constituting nano-sized and irregularly shaped rod-like structure with particle size approximately ranges from 90 to 160 nm. The total weight loss of the BSCF5564 sample comes out to be 6.6%, indicating that quadrivalence state Co4+ and Fe4+ in the sample have been completely reduced to the trivalent state Co3+ and Fe3+ due to thermal analysis. The value of Ea for BSCF5564 prepared by NECC was 0.2288 eV. The electrical conductivity of BSCF5564 synthesized by NECC is observed to be steady at high temperature (above 700 °C). 相似文献
19.
Microfluidics and Nanofluidics - Single-cell nucleic acid analysis aims at discovering the genetic differences between individual cells which is well known as the cellular heterogeneity. This... 相似文献
20.
Effect of cooling methods on residual compressive strength and cracking behavior of fly ash concretes exposed at elevated temperatures 下载免费PDF全文
This paper presents the effects of cooling methods on residual compressive strength and cracking behavior of concretes containing four different class F fly ash contents of 10%, 20%, 30% and 40% as partial replacement of cement at various elevated temperatures. The residual compressive strength of the aforementioned fly ash concretes is measured after being exposed to 200, 400, 600 and 800 °C temperatures and two different cooling methods, for example, slow cooling and rapid water cooling. Results show that the residual compressive strengths of all fly ash concretes decrease with increase in temperatures irrespective of cooling regimes, which is similar to that of ordinary concrete. Generally, control ordinary concrete and all fly ash concretes exhibited between 10% and 35% more reduction in residual compressive strength because of rapid cooling than slow cooling except few cases. Cracks are observed over concrete specimens after being exposed to temperatures ranging from 400 to 800 °C. Samples that are slowly cooled developed smaller cracks than those rapidly cooled. At 800 °C, all fly ash concretes that are exposed to rapid cooling showed the most severe cracking. X‐ray diffraction analysis shows reduction of Ca(OH)2 peak and formation of new calcium silicate peak in concretes containing 20% and 40% fly ash when subjected to 800 °C in both cooling methods. Thermo gravimetric analysis and differential thermal analysis results show increase in thermal stability of concrete with increase in fly ash contents. The existing Eurocode also predicted the compressive strength of fly ash concretes with reasonable accuracy when subjected to the aforementioned elevated temperatures and cooling methods. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献