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101.
ar Ceylan KOAK KOAK Süleyman ükriye KARABBEROLU Zekerya DURSUN 《Turkish Journal of Chemistry》2020,44(1):125
Dimethylamine borane (DMAB) is a promising fuel alternative for fuel cell applications. In this work cyclic voltammetric behavior of DMAB was investigated on the polymerized aminophenol film decorated with Ag nanoparticles in alkaline media. The polymer film was formed on the glassy carbon electrode by electrochemical technique and then, the surface was modified with Ag nanoparticles. The surface of the modified electrode was identified by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and electrochemical impedance spectroscopy techniques. The developed electrode has displayed high electrocatalytic activity for DMAB oxidation in alkaline media depending on the supporting electrolyte concentration. Experimental parameters such as cycle number used in electropolymerization of p-aminophenol, deposition of Ag nanoparticles and supporting electrolyte were optimized. 相似文献
102.
The study of integrable systems and the notion of integrability has been re-energized with the discovery that infinite-dimensional systems such as the Korteweg-de Vries equation are integrable. In this paper, the following novel aspects of integrability are described: (i) solutions of Darboux, Brioschi, Halphen-type systems and their relationships to monodromy problems and automorphic functions, (ii) computational chaos in integrable systems, (iii) we explain why we believe that homoclinic structures and homoclinic chaos associated with nonlinear integrable wave problems, will be observed in appropriate laboratory experiments. 相似文献
103.
M. J. Ablowitz C. Ahrens G. Biondini S. Chakravarty A. Docherty 《Theoretical and Mathematical Physics》2005,144(1):881-887
Periodic-group-delay (PGD) dispersion-compensation modules have recently been proposed as mechanisms to alleviate collision-induced timing shifts in dispersion-managed (DM) systems. We obtain frequency and timing shifts in quasilinear DM systems with PGDs and show that significant reductions are achieved when even a small fraction of the total dispersion is compensated by PGDs.__________Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 144, No. 1, pp. 6–13, July, 2005. 相似文献
104.
The response of giant magnetoresistance (GMR) devices depends critically on the film microstructure, with parameters such
as layer thickness and interfacial abruptness being crucial. This paper presents results obtained using high resolution electron
microscopy (HREM), chemical mapping and atom probe microanalysis. Local variations in the magnetic properties are induced
by the microstructure and also when the films are patterned to form small elements. These lead to changes in the magnetization
reversal mechanism. Some results of the studies of the magnetization reversal carried out using in situ in Lorentz transmission electron microscopy (LTEM) magnetizing experiments are also included. 相似文献
105.
We have studied the peak effect (PE) phenomenon in single crystals of weakly pinned superconductors CeRu2 and 2H-NbS2. 2H-NbS2 is iso-structural and iso-electronic to 2H-NbSe2, whose similarity with CeRu2 as regards the PE representing the order-to-disorder transformation of the flux line lattice was claimed some time ago. We
report on the step change in equilibrium magnetization across the peak effect in CeRu2. We also present the vortex phase diagram of 2H-NbS2 obtained from the magnetization data, and compare the PE phenomenon in 2H-NbS2 and 2H-NbSe2. 相似文献
106.
A.K. Chakravarty 《European Journal of Operational Research》1982,9(4):353-358
For the problem “maximize cx, subject to Ax?b, x?0 and a single 0–1 integer constraint dy?β, β?0, yi = 1 when xi > 0 and zero otherwise”, it is shown that only the feasible extreme points of Ax?b, x?0 need be searched. An adjacent vertex cut technique is developed to exclude, one at a time, the extreme points which are infeasible with respect to dy?β. In the concluding section, we also discuss the simple extension of the procedure to the case of multiple 0–1 constraints. 相似文献
107.
Metal-based netropsin mimics showing AT-selective DNA binding and DNA cleavage activity at red light
Copper(II) bis-arginate [Cu(l-arg)2](NO3)2 (1) and [Cu(l-arg)(phen)Cl]Cl (2) as mimics of the minor-groove-binding natural antibiotic netropsin show preferential binding to the AT-rich region of double-stranded DNA. The complexes with a d-d band near 600 nm display oxidative DNA cleavage activity on photoirradiation at UV-A light of 365 nm and at red light of 647.1 nm (Ar-Kr laser) in a metal-assisted photoexcitation process forming singlet oxygen (1O2) species in a type-2 pathway. 相似文献
108.
Daniel M. Walden Yogesh Bundey Aditya Jagarapu Victor Antontsev Kaushik Chakravarty Jyotika Varshney 《Molecules (Basel, Switzerland)》2021,26(1)
Amorphous solid dispersions (ASDs) have emerged as widespread formulations for drug delivery of poorly soluble active pharmaceutical ingredients (APIs). Predicting the API solubility with various carriers in the API–carrier mixture and the principal API–carrier non-bonding interactions are critical factors for rational drug development and formulation decisions. Experimental determination of these interactions, solubility, and dissolution mechanisms is time-consuming, costly, and reliant on trial and error. To that end, molecular modeling has been applied to simulate ASD properties and mechanisms. Quantum mechanical methods elucidate the strength of API–carrier non-bonding interactions, while molecular dynamics simulations model and predict ASD physical stability, solubility, and dissolution mechanisms. Statistical learning models have been recently applied to the prediction of a variety of drug formulation properties and show immense potential for continued application in the understanding and prediction of ASD solubility. Continued theoretical progress and computational applications will accelerate lead compound development before clinical trials. This article reviews in silico research for the rational formulation design of low-solubility drugs. Pertinent theoretical groundwork is presented, modeling applications and limitations are discussed, and the prospective clinical benefits of accelerated ASD formulation are envisioned. 相似文献
109.
110.
Prasad P Khan I Sasmal PK Koley D Kondaiah P Chakravarty AR 《Chemical communications (Cambridge, England)》2011,47(13):3954-3956
Planar triazinium cationic species, from VO(2+)-assisted cyclization of 1-(2-thiazolylazo)-2-naphthol, shows efficient DNA intercalative binding, visible light-induced anaerobic plasmid DNA photocleavage activity and photocytotoxicity in HeLa and MCF-7 cancer cells by an apoptotic pathway with selective localization of the compound in the nucleus as evidenced from the nuclear staining and confocal imaging. 相似文献