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73.
A comparison theorem and a uniqueness corollary for positive solutions to the equation
i=1n (pi(x,u)uxi)xi + q(x,u)u = 0
on the closure of a bounded open set are found. The important hypotheses on the nonlinear coefficients are that each pi is positive and monotone increasing in u while q is monotone decreasing in u. An application is made to equations arising in the theory of chemical reactors.  相似文献   
74.
We report our results pertaining to the use of injectable autologous collagen for the correction of dysphonia resulting from a glottic gap. To date 20 cases have been treated, 13 of which were for unilateral vocal fold immobility and 7 for sulcus vergeture and/or scar. Collagen is extracted from the skin. Approximately 5 cm2 is necessary to yield 2 ml. Injection must take place in the deep layer of Reinke's space. No patient suffered from any local or general intolerance. The phonatory glottic gap was totally or partially closed. In the paralysis group, the improvements were the following: the median maximum phonation time improved from 5.8 seconds to 11 seconds, the median mean flow rate from 0.13 ml/s to 0.09 ml/s, the median glottic gap from 8.4 to 4.5 ml/dB per s, the median intensity range from 21 to 29 dB, and the median frequency range from 141 to 195 Hz. The spectral analysis layout classification improved from 2 to 3.  相似文献   
75.
A tunable diode laser was used to perform measurements of absolute lines intensities in the ν1 fundamental of carbonyl sulfide. Spectra have also been recorded for the following isotopic species: 16O12C34S, 16O13C32S and 16O12C33S. The vibrational band strength Sv0 was calculated at 298 K. The absolute intensity for 100% of 16O12C32S species is found to be Sv0 = 29.69 ± 0.15 cm−2 atm−1 with the uncertainty covering three times the standard deviation. We have tried to determine the α-coefficient involved in the Hermann-Wallis factor F = (1 + αm + )2 and the value is found to be negligible (−5 ± 8) × 10−5. The Sv0 value obtained for the other isotopic species is very close to the normal one.  相似文献   
76.
We use Anti-de Sitter quantum field theory to prove a new class of identities between hypergeometric functions related to the Källén-Lehmann representation of products of two Anti-de Sitter two-point functions. A rich mathematical structure emerges. We apply our results to study the decay of unstable Anti-de Sitter particles. The total amplitude is in this case finite and Anti-de Sitter invariant.  相似文献   
77.
We characterize the phase shift induced by reflection on a multilayer mirror in the extreme UV range (80-93?eV) using two techniques: one based on high order harmonic generation and attosecond metrology (reconstruction of attosecond beating by interference of two-photon transitions), and a second based on synchrotron radiation and measurements of standing waves (total electron yield). We find an excellent agreement between the results from the two measurements and a flat group delay shift (±40?as) over the main reflectivity peak of the mirror.  相似文献   
78.
The MiniBooNE experiment at Fermilab reports results from a search for ˉν_{μ}→ˉν_{e} oscillations, using a data sample corresponding to 5.66×102? protons on target. An excess of 20.9±14.0 events is observed in the energy range 475相似文献   
79.
The application of the G-SERFph pulse sequence is presented on enantiomeric mixtures dissolved in a chiral liquid crystal. It aims at editing, within one single 2D spectrum, every proton coupling which is experienced by a given proton site in the molecule, and leads to real phased T-edited spectroscopy (T=J+2D). This NMR experiment is based on the combination of homonuclear semi-selective refocusing techniques with a spatial frequency encoding of the sample. This approach, which consists in handling selectively each coupling in separate cross sections of the sample, is applied to the visualization of enantiomers dissolved in a chiral liquid crystalline phase. Advantages and limits of this methodology are widely discussed.  相似文献   
80.
A B(1) field gradient-based method previously described for the detection of mechanical vibrations has been applied to detect oscillatory motions in condensed matter originated from acoustic waves. A ladder-shaped coil generating a quasi-constant RF-field gradient was associated with a motion-encoding NMR sequence consisting in a repetitive binomial 13;31; RF pulse train (stroboscopic acquisition). The NMR response of a gel phantom subject to acoustic wave excitation in the 20-200 Hz range was investigated. Results showed a linear relationship between the NMR signal and the wave amplitude and a spectroscopic selectivity of the NMR sequence with respect to the input acoustic frequency. Spin displacements as short as a few tens of nanometers were able to be detected with this method.  相似文献   
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