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41.
An accurate finite element scheme for computing 3D‐axisymmetric incompressible free surface and interface flows is proposed. It is based on the arbitrary Lagrangian Eulerian (ALE) approach using free surface/interface‐resolved moving meshes. Key features like the surface force, consisting of surface tension and the local curvature, and jumps in the density and viscosity over different fluid phases are precisely incorporated in the finite element formulation. The local curvature is approximated by using the Laplace–Beltrami operator technique combined with a boundary approximation by isoparametric finite elements. A new approach is used to derive the 3D‐axisymmetric form from the variational form in 3D‐Cartesian coordinates. Several test examples show the high accuracy and the robustness of the proposed scheme. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
42.
Sanjay S. Latthe Hiroaki Imai V. Ganesan Charles Kappenstein A. Venkateswara Rao 《Journal of Sol-Gel Science and Technology》2010,53(2):208-215
Optically transparent silica films were prepared at room temperature (~27°C) by keeping the molar ratio of TEOS:MeOH:H2O (0.001 M NH4F) constant at 1:19.29:6.20, respectively. A surface chemical modification of the films was done with alkylchlorosilanes at
different concentrations from 0 to 1 vol. % and aging times varied from half to 2 h. The DMCS and TMCS surface modified silica
films showed the static water contact angle of 146° and 162°, respectively. When the DMCS and TMCS modified films were cured
at temperatures higher than 240 and 275°C, respectively, the films became superhydrophilic. Further, the humidity study was
carried out at a relative humidity of 90% at 30°C temperature over 60 days. We characterized the water repellent silica films
by Fourier transform infrared spectroscopy, scanning electron microscopy, atomic force microscopy, % of optical transmission,
humidity tests and contact angle measurements. 相似文献
43.
Sulata Kumari Sahu Rajesh Ganesan T. Gnanasekaran 《The Journal of chemical thermodynamics》2010,42(1):1-7
Standard molar Gibbs free energy of formation of ternary oxides Pb5CrO8(s), Pb2CrO5(s), and PbCrO4(s) were determined by measuring equilibrium oxygen partial pressures over relevant phase fields using manometry and solid oxide electrolyte based emf methods and are given by: 相似文献
44.
Haladhara Naik Guinyun Kim Ashok Goswami Sarbjit Singh Vijay Kumar Manchanda Devesh Raj Srinivasan Ganesan Young Do Oh Hee-Seock Lee Kyung Sook Kim Man-Woo Lee Moo-Hyun Cho In Soo Ko Won Namkung 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(2):439-445
The mass–yield distributions of various fission products have been determined in the 50-, 60- and 70-MeV end point bremsstrahlung induced fission of natPb using off-line γ-ray spectrometric technique in the electron linac at Pohang Accelerator Laboratory, Korea. The mass–yield distributions are symmetric with average mass of 102.34, 102.25 and 102.03 and FWHM of 21, 22 and 23 mass unit, respectively. From the present data and literature data in the 50–85 MeV bremsstrahlung induced fission of 209Bi the following observations were obtained: (i) The average masses of the yield distributions in the 50–85 MeV bremsstrahlung induced fission of natPb and 209Bi are around 102.25 ± 0.25 and 103 ± 0.5, respectively. (ii) The FWHM of the mass–yield distributions increases from about 21 mass units at 50 MeV to 23 mass units at 70–85 MeV, which is explained from the point of increase in multi-chance fission probability with increasing excitation energy. (iii) Within the bremsstrahlung energy range of 50–85 MeV, the role of nuclear structure effect in the mass–yield distribution was observed in the photo-fission of 209Bi, whereas it was not seen in case of natPb. This may be due to the presence of so many isotopes in natPb unlike mono-isotopic 209Bi. 相似文献
45.
Zinc oxide thin films have been deposited on glass substrates at a substrate temperature of 673 K by spray pyrolysis. The
samples are annealed in ambient atmosphere at various temperatures. The effect of annealing on structural, electrical, and
optical properties of ZnO films has been investigated. X-ray diffraction patterns show that crystallinity of the ZnO films
has been improved after annealing. The morphology of ZnO thin films is studied by atomic force microscopy. The tensile strain
(compressive stress) is found to decrease with increase in annealing temperature which indicates the relaxation of tensile
strain in ZnO thin films. A decrease in energy band gap is observed with increase of annealing temperature. The mechanism
of blue-green luminescence of ZnO thin film has been analyzed. The resistivity is found to decrease with annealing temperature. 相似文献
46.
H. Naik P. M. Prajapati S. V. Suryanarayana P. N. Pathak D. R. Prabhu V. Chavan D. Raj P. C. Kalsi A. Goswami S. Ganesan V. K. Manchanda 《The European Physical Journal A - Hadrons and Nuclei》2011,47(8):1-5
The νp process is a primary nucleosynthesis process which occurs in core-collapse supernovae. An essential role in this process is being played by electron antineutrinos. They generate, by absorption on protons, a supply of neutrons which, by (n, p) reactions, allow to overcome waiting point nuclei with rather long beta-decay and proton-capture lifetimes. The synthesis of heavy elements by the νp process depends sensitively on the $\bar \nu _e$ luminosity and spectrum. As has been shown recently, the latter are affected by collective neutrino flavor oscillations which can swap the $\bar \nu _e$ and $\bar \nu _{\mu ,\tau }$ spectra above a certain split energy. Assuming such a swap scenario, we have studied the impact of collective neutrino flavor oscillations on the νp-process nucleosynthesis. Our results show that the production of light p-nuclei up to mass number A = 108 is very sensitive to collective neutrino oscillations. 相似文献
47.
Finite-difference solution of the transient natural convection flow of an incompressible viscous fluid past an impulsively
started semi-infinite vertical plate with variable surface temperature and mass flux is presented here. The Velocity profiles
are compared with exact solution and are found to be in good agreement. The steady-state velocity, temperature and concentration
profiles are shown graphically. It is observed that there is a rise in the velocity due to the presence of a mass diffusion.
The local as well as average skin-friction, Nusselt number and Sherwood number are shown graphically.
Received on 27 May 1998 相似文献
48.
Mariappan Periasamy Subramaniapillai Selva Ganesan Surisetti Suresh 《Tetrahedron: Asymmetry》2010,21(4):385-392
β-Amino esters were obtained in up to 78% yield with 72:28–96:4 diastereomeric ratios by the reaction of the chiral titanium enolate of menthyl esters, prepared using the TiCl4/Et3N reagent system with prochiral imines. A representative syn-β-amino ester derivative has been used for the resolution of racemic mandelic acid to obtain a sample with >99% ee in a single step. A representative syn-β-amino ester was converted to the corresponding N-deprotected amino ester using the Pd–C/HCOOH reagent system, and then to the corresponding β-amino acid using the glacial CH3COOH/HCl reagent system, and to the corresponding β-lactam derivative with partial epimerization by the reaction using C2H5MgBr. 相似文献
49.
Synchronous Fluorescence Spectroscopy for the Detection and Characterization of Cervical Cancers In Vitro 总被引:1,自引:0,他引:1
Jeyasingh Ebenezar Prakasarao Aruna Singaravelu Ganesan 《Photochemistry and photobiology》2010,86(1):77-86
The objective of this study was to assess the diagnostic potential of synchronous fluorescence (SF) spectroscopy (SFS) technique for the detection and characterization of normal and different malignancy stages of moderately differentiated squamous cell carcinoma (MDSCC), poorly differentiated squamous cell carcinoma (PDSCC) cervical tissues. SF spectra were measured from 45 biopsies from 30 patients in vitro . Characteristic, highly resolved peaks and significant spectral differences between normal and MDSCC, PDSCC cervical tissues were obtained. Nine potential ratios were calculated and used as input variables for a discriminant analysis across different groups. The potentiality of the SFS technique was estimated by two discriminant analyses. Discriminant analysis I performed across normal and abnormal (including MDSCC and PDSCC) cervical tissues classified as 100% both original and the cross-validated grouped cases. In discriminant analysis II performed across the three groups, normal, MDSCC and PDSCC, 100% of both original and the cross-validated grouped cases were correctly classified. Using the SFS technique, one can obtain all the key biochemical markers such as tryptophan, collagen, hemoglobin, reduced form of nicotinamide adenine dinucleotide and flavin adenine dinucleotide in a single scan and hence they can be targeted as tumor markers in the detection of normal from abnormal cervical tissues. 相似文献
50.
N. Venugopalan Pillai R. Vinodkumar V. Ganesan Peter Koshy V. P. Mahadevan Pillai 《Pramana》2010,75(6):1157-1161
BaWO4 doped with ZnO (2, 3, 5, 7 and 10 wt%) nanostructured films are prepared on quartz substrates by pulsed laser ablation. The
films are post annealed at 900°C. GIXRD analysis of the post-annealed films reveal the change of orientation of scheelite
tetragonal crystal growth from 1 1 2 reflection plane to 0 0 4 planes when doping concentration is more than 3 wt%. The AFM
images show that film with 7 wt% ZnO doping concentration has good ceramic pattern with surface features giving a minimum
value of rms surface roughness suitable for optoelectronic device applications. The optical transmittance and band-gap energy
of the films are found to decrease considerably on postannealing which can be due to the increase in grain size of the crystallites
on annealing. Thus doping with ZnO improves the surface features of the films and increases the optical band-gap energy. 相似文献