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81.
82.
The wavenumbers of the vibration rotation band lines of 14N16O are reported for the 2Π12-2Π12, 2Π12-2Π12 and 2Π12-2Π12 subbands of the 1-0 transition in the infrared. The full set of spectroscopic constants for this band has been determined by direct approach using the analysis of Zare, Schmeltekopf, Harrop, and Albritton. In addition to the band origin ν0 and the B, D, H constants for the lower and upper vibrational levels, the following spin-orbit coupling constants have been derived: A?0 = 123.02772 ± 0.00011 and A?1 = 122.78248 ± 0.00011 (in cm?1). Apparent centrifugal corrections to these constants have been determined and the values obtained for them are A?D0 = (0.347573 ± 0.00051) × 10?3 and A?D1 = (0.337135 ± 0.00050) × 10?3cm?1. Λ-Type doubling constants evaluated by using both grating and tunable laser data are also reported.  相似文献   
83.
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   
84.
A two level two sublattice antiferromagnetic induced moment system is examined in the Green's function theory in the random phase approximation. Attentions are drawn to the effects of an externally applied magnetic field. It is shown that a “soft mode” behavior occurs at the transition field similar to that observed at the transition temperature in the absence of a field. The transition becomes first order in the RPA. The sublattice magnetizations and the transition field are significantly lowered compared to the molecular field theory results.  相似文献   
85.
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   
86.
A detailed DSC study has been done for the substance HxBPA in the temperature range 170 to 380 K and the scheme of transitions in this compound has been deduced. From X-ray work, values for the smectic layer thickness and inplane intermolecular distance have been found in two of the liquid crystalline phases, P2 and SH.  相似文献   
87.
Calculations have been carried out to investigate the contribution of an increasing total cross section to steepening of the cosmic ray energy spectrum at very high energies (E ? 1012 eV). Our results suggest that increasing total cross section contributes only a part to the steepening of primary energy spectrum at very high energies even if the composition is pure primary iron flux.  相似文献   
88.
The absolute thermopower of single phase YBa2Cu3O7 and Y0.8Er0.2Ba2Cu3O7 has been measured in the range 250 K to the superconducting transition temperature. It is found that these compounds show a large enhancement of thermopower in the range 150 K down toT c. This enhancement shows a steep exponential drop as the temperature increases from the transition temperature. The temperature variation of the enhancement is too steep to be accounted for by electron-phonon or electron-local structural excitation mechanisms.  相似文献   
89.
40Ar-emulsion interactions are studied, to investigate the question of anomalons, in twoG- 5 emulsion stacks. In about 4600 primary interactions, projectile fragments of Z≧2 for all generations have been followed until they interact or leave the stack. After careful estimation of charges of these fragments, variation of their mean free paths is studied as a function of distance from the preceding interaction. Generation effect,N h dependence and production angle effect are investigated. In addition multi-chain events are analysed separately. Our results do not show anomalons at the 6% level and are consistent with non-occurrence of anomalons. However, this experiment is not sensitive enough to rule out anomalons (with a mfp of the order of 2 to 3 cm) produced at about 1% (or less) level.  相似文献   
90.
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   
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