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991.
In this paper,we study one type of odd-order neutral delay differential equation. Suffcient conditions for the oscillation of every solution to this type of differential equation are given. 相似文献
992.
Himatkumar V. Patel Kavita A. Vyas Sudhanshu P. Pandey Francis Tavares P. S. Fernandes 《合成通讯》2013,43(18-19):1935-1940
A one-pot synthesis of 5,6-disubstituted-2-phenyl-3(2H)-pyridazinones 4 is achieved on treatment of carbanion of ethyl trimethlsiylacetate with phenylhydrazones of 1,2-dicarbonyl compounds 1. 相似文献
993.
Admira Bosnjakovic Manoj K. Mishra Hye Jung Han Roberto Romero Rangaramanujam M. Kannan 《Analytica chimica acta》2012
A dendrimer-based sandwich type enzyme-linked immunosorbent assay (ELISA) was developed for the improved detection of recombinant human tumor necrosis factor-alpha (TNF-α) for early diagnosis of perinatal diseases. Hydroxyl-terminated generation four poly(amidoamine) dendrimer (G4-OH) was used for the development of a solid phase bio-sensing platform. The surface of the ELISA plate was modified with polyethylene-glycol (PEG) and thiol-functionalized G4-OH was immobilized on the PEG-functionalized plate. A capture antibody was oxidized and covalently immobilized onto the dendrimer-modified ELISA plate, which provides favorable orientation for the antigen binding sites toward the analyte. The dendrimer-modified plate showed enhanced sensitivity, and the detection limit for TNF-α was found to be 0.48 pg mL−1, which is significantly better than the commercially available ELISA kit. The selectivity of the dendrimer-modified ELISA plate was further evaluated with a mixture of cytokines, which showed results for similar to that of TNF-α alone. The modified plate provides a greater opportunity for the detection of a wide range of cytokines and biomarkers. 相似文献
994.
Amaresh Chandra Mishra 《Physica B: Condensed Matter》2012,407(6):923-934
Magnetic thin films of NiFe and CoNiFe alloys were electrodeposited from three different deposition baths onto copper wires of 100-μm diameter. The magnetic and magnetoimpedance (MI) properties of the samples along with their microstructure were investigated as a function of thiourea additive concentrations (CT) in the plating bath. For all intermediate frequencies, the MI ratio increased with thiourea concentration in plating bath up to a critical concentration of 80 mg/l and then decreased considerably. The change in MI with thiourea concentration in electrodeposition bath was attributed to the grain size reducing action of thiourea, which in turn enhances the soft magnetic properties of the films. At higher concentration of thiourea, the sulfur inclusion increased the magnetic softness and MI value enhanced considerably. The origin of MI lies in the combined effect of domain wall motion and spin rotation, which contributes to permeability. Inductance spectroscopy (IS) was used to evaluate the magnetic characteristic of the samples by modeling coated wires in terms of equivalent electrical circuit; namely parallel LR (inductance and resistance) circuit in series with series LR circuit. The domain wall motion was found to be greatly affected by thiourea addition in the bath, which was revealed through the study of variation of these circuit parameters. The domain wall motion thereby affects the magnetic softness of samples, which is reflected in the MI enhancement. 相似文献
995.
Samjhana Pradhan Kanchan Mishra Prof. Yong Rok Lee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(46):10886-10894
A support-free heterogeneous Pd3Co nanostructured composite (NC), synthesized through a hydrothermal route, acted as an effective catalytic system in multivariate Heck-, Sonogashira-, and Suzuki-type coupling reactions of iodonium ylides. The XPS analysis of the bimetallic Pd3Co NCs confirmed the elemental composition as 75 % palladium and 25 % cobalt. Furthermore, high-resolution (HR) TEM analysis confirmed the spherical morphology of the Pd3Co bimetallic nanoparticles. The average diameter of the NCs is 14.8 nm. The coupling reaction proceeded through the generation of α-iodoenones with simultaneous migration of the phenyl group, thereby giving a scaffold with higher atom economy. The heterogeneous Pd3Co NCs were recycled and reused without any significant change in catalytic ability for up to five reaction cycles. The high concentration of Pd and association of cobalt into the lattice of palladium appears to enhance its catalytic ability for the diverse coupling reactions in comparison with its monometallic counterparts as well as with bimetallic NCs with a comparatively lesser amount of Pd. 相似文献
996.
Structural Chemistry - This study focuses on the biological prospects of oxygen-depleted calix[4]arene ligands on a protein target. Because of their extensive medical relevance, the oxygen-depleted... 相似文献
997.
Kapileswar Mishra 《国际流体数值方法杂志》2012,69(5):897-908
Barrages form an important component of hydraulic structures constructed to intercept and divert part of the available flow of a river and use it for purposes like irrigation, hydropower and domestic or industrial water supply. A flexible apron is a protection system provided in the barrage to prevent the possibility of the scour hole traveling close to the stilling basin. The turbulence kinetic energy is predicted using a 3D VOF (volume of fluid) realizable k ?? model for both horizontal and depressed flexible aprons placed downstream of the stilling basin of the barrage. The turbulence kinetic energy at the downstream end of the inclined flexible apron is comparably less compared with the horizontal flexible apron for all the cases. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
998.
This paper proposes a Heuristic algorithm in order to reduce the total number of wavelengths required to accommodate light-paths in a WDM networks with static traffic loading. Proposed algorithm is compared with Dijkstra's algorithm for average light-path length and wavelength number of network. To see the efficiency of this 01algorithm new parameter, reduced wavelength cost (RCX) has been defined. 相似文献
999.
1000.
New diorganotin(IV) complexes of a Schiff base (HL) having general formula R2Sn(L)Cl (where L is the monoanion of HL and R = n‐Bu or Ph) have been synthesized and characterized using elemental analysis, infrared, NMR (1H, 13C, 119Sn) and UV–visible spectroscopies and mass spectrometry. These investigations suggest that in these 1:1 monomeric derivatives the Schiff base ligand acts in a monoanionic bidentate manner coordinating through the Ophenolic and Nazomethine, with proposed distorted trigonal bipyramidal geometry around tin with Ophenolic and two organic groups in the equatorial plane and the Nazomethine and the third organic group in axial positions. The proposed structures have been validated by density functional theory (DFT)‐based quantum chemical calculations at the B3LYP/6‐31G(d,p)/Def2‐SVP (Sn) level of theory. The simulated UV–visible spectrum was obtained with the time‐dependent DFT method in the gas phase and in the solvent field with the integral equation formalism–polarizable continuum model. A comparative analysis of the experimental vibrational frequencies and simulated harmonic frequencies indicates a good correlation between them. An insight into the intramolecular bonding and interactions among bonds in organotin(IV) complexes of HL was obtained by means of natural bond orbital analysis. The topological and energetic properties of the electron density distribution for the tin–ligand interaction in R2Sn(L)Cl have been theoretically calculated at the bonds around the central tin atom in terms of atoms‐in‐molecules theory. The R2Sn(L)Cl complexes were screened for their in vitro antifungal activity against chosen fungal strains. 相似文献