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101.
102.
Anupama?Upadhyay R.?S.?Beniwal Ramvir?SinghEmail author 《Continuum Mechanics and Thermodynamics》2012,24(3):257-266
The modified nonlinear relations for the estimation of elastic constants of Al2O3–NiAl composite material are developed. The concept of microstructure and interconnectivity of phases at the interface is
used. Hashin–Shtrikman relations are described in their actual form and modified version of Hashin–Shtrikman relations for
bulk and shear moduli are discussed. These relations for elastic and mechanical properties are applied mainly for Al2O3–NiAl composite material. Theoretical predictions using modified relations are compared with Hashin–Shtrikman bounds and experimental
results of elastic properties for Al2O3–NiAl matrix-inclusion-based composite. It is found that the predicted values of elastic and mechanical properties using modified
relations are quite close to the experimental results. 相似文献
103.
104.
Berelli Anupama Airva Aruna Vijjulatha Manga Sreekanth Sivan Madamsetty Vijay Sagar Ravula Chandrashekar 《Journal of fluorescence》2017,27(3):953-965
Ternary Cu(II) complexes [Cu(II)(L)(bpy)Cl] 1, [Cu(II)(L)(Phen)Cl] 2 [L = 2,3–dimethyl-1-phenyl-4(2 hydroxy-5-methyl benzylideneamino)-pyrazol-5-one, bpy = 2,2′ bipyridine, phen =1,10 phenanthroline) were synthesized and characterized by elemental analyses, UV-Visible, FT-IR, ESR, Mass, thermogravimetric and SEM EDAX techniques. The complexes exhibit octahedral geometry. The interaction of the Cu(II) with cailf thymus DNA (CT-DNA) was explored by using absorption and fluorescence spectroscopic methods. The results revealed that the complexes have an affinity constant for DNA in the order of 104 M?1 and mode of interaction is intercalative mode. The DNA cleavage study showed that the complexes cleaved DNA without any external agent. The interaction of Cu(II) complexes with bovine serum albumin (BSA) was also studied using absorption and fluorescence techniques. The cytotoxic activity of the Cu(II) complexes was probed in HeLa (human breast adenocarcinoma cell line), B16F10 (Murine melanoma cell line) and HEPA1–6 celllines, complex 1 has good cytotoxic activity which is comparable with the doxarubicin drug, with IC50 values ranging from 3 to 12.6 μM. A further molecular docking technique was employed to understand the binding of the complexes towards the molecular target DNA. Investigation of the antioxidative properties showed that the metal complexes have significant radical scavenging activity potency against DPPH radical. 相似文献
105.
In this paper we analyse vibrational characteristics of piezoceramic shells surrounded by acoustic media. Main results are presented for radially polarized piezoceramic PZT5 elements of hollow cylindrical shapes. The coupling in the radial direction between the solid and the acoustic media is accounted for indirectly, via impedance boundary conditions. The model based on such impedance boundary condition approximations offers a robust simplified alternative to a full scale fluid-solid interaction modelling. By using this model, we analyse numerically the influence of the boundary conditions imposed in the axial direction for long, medium, and short (disk-like) piezoceramic elements. 相似文献
106.
J.N. Babu Reddy S. Vanishri Ganesh Kamath Suja Elizabeth H.L. Bhat D. Isakov M. Belsley E. de Matos Gomes T.L. Aroso 《Journal of Crystal Growth》2009,311(16):4044-4049
Cesium hydrogen l-malate monohydrate, CsH(C4H4O5)·H2O, is a new chiral open-framework semi-organic crystalline material with a second-harmonic generation efficiency one order of magnitude greater than KDP. Single crystals of this new material have been grown by the conventional slow cooling technique from aqueous solution. Grown crystals display both platy and prismatic morphologies depending on the imposed supersaturation. Hardness values measured using Vickers hardness indenter show considerable anisotropy. The resistivity behavior at room temperature and above, places the crystal between an ionic conductor and a dielectric. The single-crystal SHG efficiency estimated through Maker fringes experiment gives deff which is 4.24 times that of KDP. Single and multiple shot experiments performed on the grown crystals for the fundamental and second harmonic of pulsed Nd:YAG laser (1064 and 532 nm) show that it exhibits a high laser damage threshold which is a favorable property for nonlinear optical applications. 相似文献
107.
A tandem IBX‐promoted oxidation of primary alcohol to aldehyde and opening of intermediate β,γ‐diolcarbonate aldehyde to (E)‐γ‐hydroxy‐α,β‐enal has been developed. Remarkably, the carbonate opening delivered exclusively (E)‐olefin and no over‐oxidation of γ‐hydroxy was observed. The method developed has been extended to complete the stereoselective total synthesis of both (S)‐ and (R)‐coriolides and d ‐xylo‐ and d ‐arabino‐C‐20 guggultetrols. 相似文献
108.
2.5Gb/s SONET/SDH applications with reach up to 80km in standard SMF fiber, is presented.
Introduction Due to the trend towards higher port densities in high-capacity communication systems,Small Form Factor (SFF) Transceivers are becoming popular [1]. Originally, SFF transceivers were designed to address short reach (2km) and intermediate reach(15km) applications using PIN receivers [2]. We have developed SFF transceivers for the high-end SONET/SDH space (2.5Gb/s speed for 40km and 80km reach). This part of the SONET/SDH space is unique due to the need for Avalanche Photo Diode (APD) based receiver within a SFF footprint, and still maintaining a good transceiver performance is a real challenge. 相似文献
109.
This paper presents an experimental determination of the virtual mass and drag coefficients of a disk oscillating sinusoidally in a two-phase mixture of air flowing through stagnant water. The purpose of this experiment was to determine the importance of virtual mass on the transient response of an INEL-type drag-disk flow meter.The results indicate that for a given void fraction, the virtual mass coefficient increases, and the drag coefficient decreases, with increasing amplitude parameter. Also, for a given amplitude parameter, the virtual mass coefficient decreases, and the drag coefficient increases, with increasing void fraction.Based on the measured virtual mass coefficients, it was concluded that when an INEL-type drag-disk is used for the measurement of transient two-phase flows, virtual mass effects may be neglected in the analysis of its response without appreciable error. 相似文献
110.