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Daroui-Mokaddem H Kabouche A Bouacha M Soumati B El-Azzouny A Bruneau C Kabouche Z 《Natural product communications》2010,5(10):1669-1672
The essential oils of fresh leaves of Eucalyptus globulus L. (Myrtaceae), and leaves and stems of Smyrnium olusatrum L. (Apiaceae), obtained by hydrodistillation in a Clevenger-type apparatus, were analyzed by GC/MS. Twenty compounds were characterized, representing 98.3% of the essential oil of E. globulus, with 1,8-cineole (48.6%), globulol (10.9%), trans-pinocarveol (10.7%), and alpha-terpineol (6.6%) as main components, while thirty-three compounds were characterized, representing 94.3% of the essential oil of S. olusatrum, with sabinene (27.1%), curzerene (13.7%), methyl-1-benzyl-2-oxocyclooctane carboxylate (12.3%), alpha-pinene (7.2%), cryptone (7.1%) and beta-pinene (5.7%) as the major components. The essential oils of E. globulus and S. olusatrum were tested against a wide range of fungal and bacterial strains. Both oils showed significant antimicrobial activity. 相似文献
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The aim of this paper is to model and simulate the displacement of radioactive elements in a saturated heterogeneous porous medium. New schemes are proposed to solve accurately the convection–diffusion–reaction equations including nonlinear terms in the time derivative. Numerical tests show the stability and robustness of these schemes through strong heterogeneities of the medium. Finally the COUPLEX 1 benchmark concerning the far field simulation of a polluted flow by a leak of a nuclear waste disposal is performed and compared with the results available in the literature. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
16.
We introduce and study rigorously a Hamiltonian model of a classical particle moving through a homogeneous dissipative medium
at zero temperature in such a way that it experiences an effective linear friction force proportional to its velocity (at small speeds). The medium consists at each point in a space of a vibration
field modelling an obstacle with which the particle exchanges energy and momentum in such a way that total energy and momentum
are conserved. We show that in the presence of a constant (not too large) external force, the particle reaches an asymptotic
velocity proportional to this force. In a potential well, on the other hand, the particle comes exponentially fast to rest
in the bottom of the well. The exponential rate is in both cases an explicit function of the model parameters and independent
of the potential.
Received: 18 July 2001 / Accepted: 20 April 2002 Published online: 12 August 2002 相似文献
17.
In this work, a two-phase film-flow model in a hygroscopic capillary tube is developed and extended to describe the two-phase capillary viscous transport in a network of parallel capillary tubes in terms of relative permeabilities. This film-flow approach is further considered to predict the longitudinal moisture transport in oak wood during drying. Numerical results obtained from this prediction are compared with data of convective drying experiments performed on samples of this wood. The comparison seems to confirm the physical relevance of a film-flow model to correctly represent the moisture transfer until the hygroscopic regime is reached. 相似文献
18.
Chen L Roger J Bruneau C Dixneuf PH Doucet H 《Chemical communications (Cambridge, England)》2011,47(6):1872-1874
The palladium catalysed 5-arylation of 2-(trimethylsilyl)thiophene with aryl bromides via C-H bond functionalisation allows the synthesis of arylated silylthiophenes in only one step. 相似文献
19.
The directional dependence of the phonon mode frequencies is calculated in the three principal planes of biaxial sodium nitrite at 7 and 300 K, using the lattice mode parameters determined from the simulation of the infrared reflectivity spectra polarised along the three cristallographic axes. Good agreement is obtained between the calculated and experimental infrared reflectivity spectra for different orientations of the wave vector in the a-c plane of sodium nitrite. 相似文献
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F. Brehat B. Wyncke A. Hadni 《International Journal of Infrared and Millimeter Waves》1981,2(2):333-345
Conclusion Reflectivity of a single crystal sodium nitrate have been measured as a fonction of temperature and crystallographic orientations over a frequency region which spans all infrared active lattice modes. The data have been fitted with a series of five independent oscillators and an overdamped oscillator of A2u symmetry at temperatures between 250 and 276°C. None of them behaves as a soft mode. Our measurements show also the influence of the phase transition on the lattice modes parameters. 相似文献