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41.
Manimaran Kumar Murugesan Subban Ragavendran Chinnasamy Balasubramani Govindasamy Natarajan Devarajan Ganesan Abirami Seedevi Palaniappan 《Journal of Cluster Science》2021,32(5):1229-1240
Journal of Cluster Science - The titanium dioxide nanoparticles (TiO2NPs) were synthesized by the aqueous extract from P. djamor. The UV–Vis spectrum of TiO2NPs showed maximum absorption at... 相似文献
42.
Biological contour,molecular docking and antiproliferative studies of DNA targeted histidine based transition metal(II) complexes: Invention and its depiction
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A novel series of histidine derived transition metal complexes were synthesized and characterized by multispectral techniques such as UV‐Vis., FT IR, EPR, NMR, ESI‐mass analysis and other physico‐chemical methods like elemental analysis, molar conductivity, magnetic susceptibility. The synthesized compounds were attempted for their biological prospective. The biological studies involved are DNA interaction (binding and damage), antimicrobial, antioxidant, antiproliferative and molecular docking. DNA interaction studies were carried out with the help of UV‐Vis absorption titration, viscosity measurement and cyclic voltammetric techniques which revealed that the synthesized compounds could interact with CT‐DNA through intercalative binding mode. A gel electrophoresis assay demonstrated the ability of complexes to cleave the supercoiled pUC18 DNA. The antioxidant property shows that the metal complexes have preferable ability to scavenge hydroxyl radical than the ligand. Moreover, the antimicrobial assay indicates that these complexes are good antimicrobial agents against various pathogens. Furthermore, the in vitro antiproliferative activities of the complexes were examined on HeLa, Hep G2 and NIH 3 T3 cell lines using an MTT assay. The morphological changes were investigated using Hoechst 33258 staining apoptosis assay. In addition, molecular docking studies were executed to considerate the nature of binding of the synthesized complexes with protein and DNA. 相似文献
43.
We discuss fermion self energy correction in light front QED using a coherent state basis. We show that if one uses coherent state basis instead of fock basis to calculate the transition matrix elements the true infrared divergences in δ m 2 get canceled up to O(e 4). We show this in Light-front as well as in Feynman gauge. 相似文献
44.
A cost‐effective curvature calculation approach for interfacial flows on unstructured meshes
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We present a simple and cost‐effective curvature calculation approach for simulations of interfacial flows on structured and unstructured grids. The interface is defined using volume fractions, and the interface curvature is obtained as a function of the gradients of volume fractions. The gradient computation is based on a recently proposed gradient recovery method that mimicks the least squares approach without the need to solve a system of equations and is quite easy to implement on arbitrary polygonal meshes. The resulting interface curvature is used in a continuum surface force formulation within the framework of a well‐balanced finite‐volume algorithm to simulate multiphase flows dominated by surface tension. We show that the proposed curvature calculation is at least as accurate as some of the existing approaches on unstructured meshes while being straightforward to implement on any mesh topology. Numerical investigations also show that spurious currents in stationary problems that are dependent on the curvature calculation methodology are also acceptably low using the proposed approach. Studies on capillary waves and rising bubbles in viscous flows lend credence to the ability of the proposed method as an inexpensive, robust, and reasonably accurate approach for curvature calculation and numerical simulation of multiphase flows. 相似文献
45.
The compound 4 propyl paraethoxy phenyl cyclohexyl carboxylate (code name D302) is a member of a homologous series and exhibits liquid crystalline (nematic) behavior in the temperature range 48°C to 78°C. An experiment has been set up for conducting X-ray studies of liquid crystal samples at various temperatures. From X-ray studies conducted at different temperatures on D302, the apparent molecular length and inter-molecular distance and their temperature dependence have been determined. The variation of the orientational-order parameter <P2>xray has been determined from the intensities of the scanned X-ray photographs taken at different temperatures. The results have been compared with the<P2>opt values obtained by us from birefringence studies. 相似文献
46.
Numerical Algorithms - In this paper, we employ the virtual element method for the numerical solution of linear thermo-elastic problems in two dimensions. The framework is implemented within the... 相似文献
47.
V. C. Adya M. Mohapatra Nimai Pathak Mithlesh Kumar N. S. Hon S. K. Thulasidas M. J. Kulkarni V. Natarajan 《Journal of Radioanalytical and Nuclear Chemistry》2016,307(1):341-346
This work presents the investigation of some commercially available and commonly used Si3N4 foils prepared with LPCVD technique. The density and the stoichiometry of these films were determined by Rutherford backscattering spectroscopy and profilometry, while the study of impurities was achieved with particle induced X-ray emission method. It was found that the density of the studied Si3N4 films is significantly less (~2.71 g cm?3), while the stoichiometry is close to the values of the bulk material. The results were verified by measuring the ion energy loss through the films by scanning transmission ion microscopy. 相似文献
48.
Ranjini Natarajan Charles E. McCulloch 《Journal of computational and graphical statistics》2013,22(3):267-277
Abstract This article demonstrates by example that the use of the Gibbs sampler with diffuse proper priors can lead to inaccurate posterior estimates. Our results show that such inaccuracies are not merely limited to small sample settings. 相似文献
49.
Anupam Bhim Prof. Jean-Pascal Sutter Prof. Jagannatha Gopalakrishnan Prof. Srinivasan Natarajan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(6):1995-2008
The stuffed tridymite structure Ba(Zn/Co)1−xSi1−xM2xO4 (M=Al3+ and Fe3+) is explored for the possible multiferroic behavior and to develop new inorganic colored materials. The compounds were synthesized by employing conventional solid-state chemistry methods in the temperature range 1100–1175 °C for 24 h. The powder X-ray diffraction (PXRD) and Rietveld refinement studies indicate that the compounds stabilize in the P63 space group (no. 173). The refinement results were also rationalized by employing Raman spectroscopic studies. The compounds were found to be second harmonic generation (SHG) active and show weak ferroelectric behavior. The co-substitution of Co2+ and Fe3+ in the structure gives rise to a weak ferromagnetic behavior to the compound, BaCo0.75Si0.75Fe0.5O4, making it a multiferroic material. The optical studies on the prepared compounds exhibited blue color (Co2+ in Td geometry), purple color (Ni2+ in Td geometry), and simultaneous substitution of Co2+ and Fe3+ gives rise to blue-green color owing to metal-to-metal charge transfer (MMCT) effect. 相似文献
50.
A sharp‐interface immersed boundary framework for simulations of high‐speed inviscid compressible flows
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Shuvayan Brahmachary Ganesh Natarajan Vinayak Kulkarni Niranjan Sahoo 《国际流体数值方法杂志》2018,86(12):770-791
A new finite‐volume flow solver based on the hybrid Cartesian immersed boundary (IB) framework is developed for the solution of high‐speed inviscid compressible flows. The IB method adopts a sharp‐interface approach, wherein the boundary conditions are enforced on the body geometry itself. A key component of the present solver is a novel reconstruction approach, in conjunction with inverse distance weighting, to compute the solutions in the vicinity of the solid‐fluid interface. We show that proposed reconstruction leads to second‐order spatial accuracy while also ensuring that the discrete conservation errors diminish linearly with grid refinement. Investigations of supersonic and hypersonic inviscid flows over different geometries are carried out for an extensive validation of the proposed flow solver. Studies on cylinder lift‐off and shape optimisation in supersonic flows further demonstrate the efficacy of the flow solver for computations with moving and shape‐changing geometries. These studies conclusively highlight the capability of the proposed IB methodology as a promising alternative for robust and accurate computations of compressible fluid flows on nonconformal Cartesian meshes. 相似文献