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61.
62.
AnL
1-existence theorem is proved for the nonlinear stationary Boltzmann equation with hard forces and no small velocity truncation—only
the Grad angular cut-off-in a setting between two coaxial rotating cylinders when the indata are given on the cylinders. 相似文献
63.
Stephane Andrieux Amel Ben Abda Thouraya Nouri Baranger 《Comptes Rendus Mecanique》2005,333(2):171-177
We propose, in this Note, a new procedure for data completion based on the minimization of an energy like error functional. The efficiency of the proposed method is illustrated by a thermostatic application. To cite this article: S. Andrieux et al., C. R. Mecanique 333 (2005). 相似文献
64.
Bouanich JP Aroui H Nouri S Picard-Bersellini A 《Journal of Molecular Spectroscopy》2001,206(1):104-110
H(2)-broadening coefficients have been measured for 66 rovibrational lines of NH(3) at room temperature in the (P)P and (R)P branches of the nu(4) band in the range 1470-1600 cm(-1), using a high-resolution Fourier transform spectrometer. The collisional widths are obtained by fitting Voigt profiles to the measured shapes of the lines. The broadening coefficients are found to decrease on the whole as J increases and they increase with K for a given J value. The results are compared with those calculated from a semiclassical model in which the inversion vibration of NH(3) and collision-induced transitions with DeltaK = 0 and DeltaK = +/- 3 are taken into account. The intermolecular potential used includes electrostatic, induction, and dispersion energy contributions. The calculations performed by considering only DeltaK = 0 transitions provide significantly lower broadenings but with a satisfactory J and K dependence. The same trends are obtained for the broadening coefficients in inversion-rotation transitions and in the Q branch of the nu(1) parallel band of NH(3). Copyright 2001 Academic Press. 相似文献
65.
66.
The jet from an axiymmetric convergent nozzle has been investigated at pressure ratios of 1.9 and 3.6 corresponding to exit Mach numbers of unity and 1.49. Velocity characteristics were measured with a laser-Doppler velocimeter and complemented by shadography which showed the structure of the expansion-compression waves. The sinuous longitudinal variations of the axial velocity are shown to be large at the higher pressure ratio with amplitudes which decreased with increasing distance from the jet exit and from the axis. The use of the jet for the quantification of droplet breakup is considered and it is evident that the higher pressure ratio requires careful consideration of the location at which a droplet is allowed to fall into the jet.Financial support from the Ministry of Defence under agreement 2037/001/CBDE is gratefully acknowledged. 相似文献
67.
K. Daneshjou A. Nouri R. Talebitooti 《Archive of Applied Mechanics (Ingenieur Archiv)》2007,77(6):363-379
Composite structures are often used in aircraft because of advantages offered by a high strength to weight ratio. Sound transmission
through an infinite laminated composite cylindrical shell is studied in the context of the transmission of airborne sound
into aircraft interior. The shell is immersed in an external fluid medium and contains an internal fluid, and airflow in an
external fluid medium moves with a constant velocity. The different parameters were used to see how laminate specification
affected noise transmission. An exact solution is obtained by solving the vibration equation of laminated composite shell
and acoustic wave equations simultaneously. Transmission losses (TLs) obtained from numerical solution are compared with those
of other authors. The effects of different source condition, structural properties and flight conditions on TL are studied
for a range of values, especially, incident angle of the plane wave, Mach number and flight altitude of aircraft, stack sequences,
angle of warp and damping. 相似文献
68.
We prove the existence for short times of analytic solutions to a Vlasov type equation. The corresponding model is one-dimensional but uses a quite singular force term which involves a full derivative in x of the macroscopic density, making the existence of solutions a difficult question. 相似文献
69.
Simple and accurate integral equation formulation using a three dimensional finite element (3DFEM) to determine the propagation of microwave passive structures is presented. This technique is applied to solve the scattering problems due to various forms of irises in lossless rectangular waveguide.The analysis of these components is highly dependent of the numbers of modes considered in the neighbourhood of the discontinuity. The theoretical model is compared with measurements and Mode Matching Method (MMM). Results are found to be good agreement. 相似文献
70.
Bouslimani N Clément N Rogez G Turek P Bernard M Dagorne S Martel D Cong HN Welter R 《Inorganic chemistry》2008,47(17):7623-7630
We report here experimental evidence for the formation in the solid state of a new binuclear Fe (III) 2(mu-OMe) 2(HL) 4 complex (H 2L is 2-salicyloylhydrazono-1,3-dithiolane). The isostructural Mn (III) 2(mu-OMe) 2(HL) 4 complex has provided the strongest ferromagnetic interaction value (J approximately 20 cm (-1)) between Mn (III) ions to date. The new iron binuclear compound presented in this study shows antiferromagnetic intramolecular coupling, which agrees with the theoretical study that we previously proposed. During our synthetic work, we also observed an unexpected spontaneous reduction of the new Fe (III)(HL) 2Cl,S complex to the new Fe (II)(H 2L) 2Cl 2 high-spin mononuclear complex. This process has been checked by cyclo-voltammetry as well as pseudosteady voltammetry. 相似文献