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51.
This paper considers finite friction contact problems involving an elastic pin and an infinite elastic plate with a circular hole. Using a suitable class of Green's functions, the singular integral equations governing a very general class of conforming contact problems are formulated. In particular, remote plate stresses, pin loads, moments and distributed loading of the pin by conservative body forces are considered. Numerical solutions are presented for different partial slip load cases. In monotonic loading, the dependence of the tractions on the coefficient of friction is strongest when the contact is highly conforming. For less conforming contacts, the tractions are insensitive to an increase in the value of the friction coefficient above a certain threshold. The contact size and peak pressure in monotonic loading are only weakly dependent on the pin load distribution, with center loads leading to slightly higher peak pressure and lower peak shear than distributed loads. In contrast to half-plane cylinder fretting contacts, fretting behavior is quite different depending on whether or not the pin is allowed to rotate freely. If pin rotation is disallowed, the fretting tractions resemble half-plane fretting tractions in the weakly conforming regime but the contact resists sliding in the strongly conforming regime. If pin rotation is allowed, the shear traction behavior resembles planar rolling contacts in that one slip zone is dominant and the peak shear occurs at its edge. In this case, the effects of material dissimilarity in the strongly conforming regime are only secondary and the contact never goes into sliding. Fretting tractions in the forward and reversed load states show shape asymmetry, which persists with continued load cycling. Finally, the governing integro-differential equation for full sliding is derived; in the limiting case of no friction, the same equation governs contacts with center loading and uniform body force loading, resulting in identical pressures when their resultants are equal. 相似文献
52.
Bala Sundaram 《Pramana》1997,48(2):469-486
I will show how aspects of quantum chaology are relevant even in a seemingly well understood quantum phenomenon like the photoelectric
effect. This example together with recent experiments in atom optics are used to define and discuss the larger questions,
recent progress made by us in resolving some of these issues and future directions. 相似文献
53.
Sappanimuthu Thirunavukkarasu Kilambi Narasimhan Sundaram Shamundeeswari Susaimanickam Arul Antony 《Research on Chemical Intermediates》2017,43(4):2401-2414
Research on Chemical Intermediates - Herein, we report the synthesis and in vitro antibacterial and antifungal activities for twelve... 相似文献
54.
Sun C Rajasekhara S Goodenough JB Zhou F 《Journal of the American Chemical Society》2011,133(7):2132-2135
A novel solvothermal approach combined with high-temperature calcinations was developed to synthesize on a large scale LiFePO(4) microspheres consisting of nanoplates or nanoparticles with an open three-dimensional (3D) porous microstructure. These micro/nanostructured LiFePO(4) microspheres have a high tap density and, as electrodes, show excellent rate capability and cycle stability. 相似文献
55.
Neelakantan MA Sundaram M Nair MS 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,79(5):1693-1703
Several mixed ligand Ni(II), Cu(II) and Zn(II) complexes of 2-amino-3-hydroxypyridine (AHP) and imidazoles viz., imidazole (him), benzimidazole (bim), histamine (hist) and L-histidine (his) have been synthesized and characterized by elemental and spectral (vibrational, electronic, 1H NMR and EPR) data as well as by magnetic moment values. On the basis of elemental analysis and molar conductance values, all the complexes can be formulated as [MAB]Cl except histidine complexes as MAB. Thermogravimetric studies reveal the presence of coordinated water molecules in most of the complexes. From the magnetic measurements and electronic spectral data, octahedral structure was proposed for Ni(II) and Cu(II)-AHP-his, tetrahedral for Cu(II)-AHP-him/bim/hist, but square planar for the Cu(II)-AHP complex. The g∥/A∥ calculated supports tetrahedral environment around the Cu(II) in Cu(II)-AHP-him/bim/hist and distorted octahedral for Cu(II)-AHP-his complexes. The morphology of the reported metal complexes was investigated by scanning electron micrographs (SEM). The potentiometric study has been performed in aqueous solution at 37 °C and I=0.15 mol dm(-3) NaClO4. MABH, MAB and MAB2 species has been identified in the present systems. Proton dissociation constants of AHP and stability constants of metal complexes were determined using MINIQUAD-75. The most probable structure of the mixed ligand species is discussed based upon their stability constants. The in vitro biological activity of the complexes was tested against the Gram positive and Gram negative bacteria, fungus and yeast. The oxidative DNA cleavage studies of the complexes were performed using gel electrophoresis method. Cu(II) complexes have been found to promote DNA cleavage in presence of biological reductant such as ascorbate and oxidant like hydrogen peroxide. 相似文献
56.
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58.
K. A. R. Sundaram Srinivasan 《International journal of quantum chemistry》1977,12(4):671-681
A method recently developed for the calculation of intramolecular nonbonded interactions based on experimental bond polarisabilities and atomic charges and transition π-charges obtained from MO calculations has been applied to the alanyl dipeptide. The potential energy contours in the ?, ψ plane obtained by this method compare favourably with those derived from the frequency of occurrence of conformations in globular proteins. An analysis of the various components of the nonbonded interaction energy indicates that the fairly frequent occurrence of conformations around ? = ?80°, ψ=0° is presumably due to a favourable interaction of the π-polarisation. 相似文献
59.
The flow and heat transfer problem with viscous dissipation for electrically conducting non-Newtonian fluids with power-law
model in the thermal entrance region of two parallel plates with magnetic field under constant heat flux and constant wall
temperature conditions has been studied. The governing equations have been solved numerically using quasilinearization technique
and implicit finite-difference scheme. It has been found that the effect of viscous dissipation on heat transfer is quite
significant for heating and cooling conditions at the wall. 相似文献
60.