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991.
Large amplitude flexural vibrations of slender beams, and thin circular and rectangular plates have been studied when a compatible longitudinal or inplane mode is coupled with the fundamental flexural mode. It is shown that the effect of longitudinal or inplane deformation and inertia is to reduce the non-linearity in the flexural frequency-amplitude relationship. Further, for slender beams and thin plates, the effect of longitudinal or inplane inertia is negligible. 相似文献
992.
993.
V. V. Ramana Rao 《Proceedings Mathematical Sciences》1972,75(4):189-198
A theoretical analysis is made of the flow of a conducting viscous and incompressible fluid through a straight annular pipe of circular cross-section flowing under a constant pressure gradient. The pipe is rotated about an axis perpendicular to it and also there is imposed a uniform magnetic field transverse to the motion. The secondary flow pattern has been studied in detail for small values of angular velocity and Hartman number. 相似文献
994.
G. S. Deshmukh A. L. J. Rao S. V. S. S. Murty 《Fresenius' Journal of Analytical Chemistry》1963,196(3):183-186
Summary A well defined wave for manganese in 1 M sodium formate solution is reported and its use for the determination of microquantities of the element is indicated. Several foreign ions studied do not cause any interferences.
Zusammenfassung Die polarographische Bestimmung von Mikromengen Mangan kann mit gutem Erfolg in einer Grundlösung aus 1 m Natriumformiat durchgeführt werden. Eine Anzahl untersuchter Anionen verursacht keine Störungen.相似文献
995.
A satisfactory quantitative method for the determination of lead as lead molybdate by precipitation from a homogeneous solution has been developed. The method employs the diffusion of ammonia into a solution containing lead and sodium molybdate in nitric acid medium. The precipitation of lead in the range of 28·0–280·0 mg is complete within 8–9 hours. Anions like sulphate, arsenate, phosphate, tungstate and chromate in moderate concentrations and cations such as Zn (II), Cu (II), Ni (II), Co (II), Mn (II), Cd (II), Hg (II), Ag (I), Ti (IV), As (V), Mg (II) and Al (III) do not contaminate the precipitate. The precipitate gets constant weight at 120°. This eliminated the ignition of the precipitate,i.e., the contamination of molybdic oxide by the precipitate was reduced. 相似文献
996.
997.
998.
Stokes’ and Seth’s solutions for the slow motion of a sphere in a viscous, incompressible liquid have been discussed from the viewpoint of the structure of the velocity field and its relation to the drag of the sphere. The problem is analysed from a different angle in this paper. It is believed that it throws more light on thephysics of the problem. 相似文献
999.
A. Baldacci V. Malathy Devi Da-Wun Chen K. Narahari Rao B. Fridovich 《Journal of Molecular Spectroscopy》1978,70(1):143-159
The absorption spectrum of carbon dioxide has been recorded in the wavenumber region 2395-2216 cm?1 with a spectral resolution between 0.02 and 0.03 cm?1. About twenty transitions have been identified and the molecular constants of the levels involved have been evaluated. In view of the interest of this region in atmospheric studies a map of the entire spectrum recorded by using a normal sample of carbon dioxide is presented including the identifications for the different bands. About 90% of the lines observed have been interpreted. Some of them have been assigned to transitions originating from higher excited states of 12C16O2 not considered before in interpreting this spectral region. For the first time, bands of 12C16O17O have been identified in the 4.3-μm spectra obtained with the natural sample. 相似文献
1000.
Pushpa M. Rao A. Venugopalan S.A. Ahmad G.D. Saksena 《Spectrochimica Acta Part B: Atomic Spectroscopy》1985,40(8):1059-1066
Isotope shifts ΔT (170-166) have been evaluated for 54 even and 94 odd energy levels covering almost all the known configurations of the neutral erbium. These ΔT values have been derived from the isotope shift measurements carried out in 159 lines in the region 3900–4605 A using a Fabry-Perot spectrometer and liquid-air-cooled hollow cathode source with highly enriched 170Er and 166Er isotopic samples. Electronic configurations assigned to energy levels of Er I by earlier workers have been mostly confirmed and in few cases revisions have been suggested on the basis of observed ΔT values. Probable configurations have been also suggested for unassigned levels of Er I, and a large number of even levels could be assigned to 4f11 5d 6s 6p configuration. 相似文献