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Maurice M. Bursey Donald J. Harvan J. Ronald Hass 《Journal of mass spectrometry : JMS》1985,20(3):197-201
Unimolecular and collision-induced decomposition products of [C4(C6H5)2(C6H4F)2]+˙ generated from four unsymmetrical sources include [C14H10]+˙ and [C14H8F2]+˙ and so provide evidence for a tetrahedral intermediate. Other decompositions show substantial influence of the position of the ρ-fluorophenyl ring on ion energy distributions. This influence may be related to the reported absence of peaks diagnostic for the tetrahedral intermediate from the spectrum of the equivalent ion from the appropriate 13C-labeled analog. Alternatively the difference in spectra can be correlated with lifetimes of ions. 相似文献
244.
Maurice Prud'homme 《Analytical and bioanalytical chemistry》1907,46(2-3):185-186
245.
Stphane Ayache Maurice Ouaknine Philippe Dejonkere Pierre Prindere Antoine Giovanni 《Journal of voice》2004,18(1):107-115
Numerous clinical findings indicate that viscosity of laryngeal mucosa is a crucial factor in glottal perfomance. Experience using experimental test benches has shown the importance of humidifying air stream used to induce vibration in excised larynges. Nevertheless, there is a lack of knowledge particularly regarding the physicochemical properties of laryngeal mucus. The purpose of this study was to research vocal fold vibration in excised larynges using artificial mucus of precisely known viscosity. Eight freshly harvested porcine larynges were examined. Parameters measured were Fo and vocal fold contact time. Measurements were performed under three conditions: basal (no fluid application on vocal cord surface), after application of a fluid of 60cP viscosity (Visc60), and after application of a fluid of 100cP viscosity (Visc100). Electroglottographic measurements were performed at two different times for each condition: 1 s after airflow onset (T1) and 6 seconds after airflow onset (T2). Statistical analysis consisted of comparing data obtained under each condition at T1 and T2. The results showed a significant decrease in Fo after application of Visc60 and Visc100 fluids and a decrease in Fo at T2. Closure time was significantly higher under Visc60 conditions and under Visc100 conditions than under basal conditions. Application of artificial mucus to the mucosa of the vocal folds lowered vibratory frequency and prolonged the contact phase. Our interpretation of this data is that the presence of mucus on the surface of the vocal folds generated superficial tension and caused adhesion, which is a source of nonlinearity in vocal vibration. 相似文献
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Maurice Koster 《Mathematical Methods of Operations Research》2006,64(3):429-444
The directional serial rule is introduced as a natural serial extension, generalizing the Moulin–Shenker cost sharing rule to heterogeneous cost sharing models. It is the unique regular rule compatible with the radial serial principle. In particular, this shows the incompatibility of the serial principle with differentiability of a cost sharing rule as a function of the individual demands.I would like to thank the editor and the referee for their comments which have been most useful. 相似文献
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D. Lacour O. Durand J. -L. Maurice H. Jaffrs F. Nguyen Van Dau F. Petroff P. Etienne J. Humbert A. Vaurs 《Journal of magnetism and magnetic materials》2004,270(3):403-406
We have investigated the magnetic behavior and the structural properties of ferromagnetic–antiferromagnetic systems (NiFe–IrMn and Co–IrMn) deposited directly on a thin tantalum buffer layer (bottom configuration) or above a thin Al2O3 tunnel barrier layer (top configuration). In the bottom configuration, the bilayer system exhibits higher magnetic performances than in the top configuration in terms of thermal stability. We have performed a detailed structural study by X-ray diffraction and high-resolution transmission electron microscopy which allow us to establish a clear correlation between the situation of the bilayer with respect to the tunnel barrier, its texture and its magnetic properties. 相似文献
250.
Maurice Kleman 《Liquid crystals》1988,3(10):1355-1367
Starting from recent experiments in non-ionic surfactants, we discuss various topics characteristic of low rigidity K1 materials. (1) The stability of the lamellar and cubic phases is studied in a simple model involving K2 the saddle-splay constant K2, and entropy terms due to the chains. We expect the lamellar phase to have a large range of existence, and the cubic phase to be of small extent. (2) We compare to cubic phases stability in large K1 materials. We discuss the mobility of edge dislocations on the basis of a new model of the core which involves stretching of the core layers in one dimension, and easy nucleation of pores in this region. The core extension is a characteristic length of low K1 materials which is much larger than de Gennes' length for microemulsions with a similar low K1. 相似文献