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991.
992.
K. El harfi C. Bennouna A. Mokhlisse M. Ben chana L. Leme J. Joffre A. Ambls 《Journal of Analytical and Applied Pyrolysis》1999,50(2):163-174
Timahdit oil shale was subjected to supercritical water extraction. The results reveal significant difference in oil yields and composition when compared with those obtained from conventional pyrolysis. In addition, the effect of temperature and residence time on the supercritical water extraction of oil was investigated in a set of three experiments. The results revealed that the yield and the fraction of paraffins and aromatics increase while the percentage of asphaltenes decreases as the temperature is increased from 380 to 400°C. The residence time was found to affect the yield and the fraction of asphaltenes and polar compounds. 相似文献
993.
Horseradish peroxidase (HRP) catalyzes the oxidation of a wide variety of compounds inthe presence of hydroperoxide. The products have been used as the important materialsin extensive fields because of the con juged bond. Many investigators have stUdied themechanism of HRP. When native HRP reacts with hydroperoxide, compound i, which istwo oxidizing equivalents of the ferric state of HRP, is formed. Compound I issubsequently reduced by one electron to form compound 11. Reduction of compo… 相似文献
994.
Holograms recorded with a number of reference beams are sensitive to alignment when reconstructed. Interference effects due to misalignment are evaluated, and as a result optimal recording parameters can be suggested. 相似文献
995.
Gérard Ben Arous Marc Brunaud 《Stochastics An International Journal of Probability and Stochastic Processes》2013,85(1-4):79-144
This article concerns the asymptotic behaviour of diffusions consisting of various systems of mean-field type interacting particles. We specifically study the following properties: propagation of chaos; critical and non critical fluctuations, using the Laplace method which has been developed by Bolthausen in the general Banach valued random variables context; and finally the large deviations of laws of trajectorial empirical measures. We also study Gibbs variational formula associated with this problem and show that it reduces to a finite dimensional problem 相似文献
996.
997.
Nataša Mršić Thomas Jerphagnon Adriaan J. Minnaard Ben L. Feringa Johannes G. de Vries 《Tetrahedron: Asymmetry》2010,21(1):7-10
The rhodium-catalyzed asymmetric hydrogenation of 2-substituted N-protected-indoles using monodentate phosphoramidites as ligands was examined. Full conversion and 74% ee, were obtained with a catalyst based on PipPhos. The use of a catalytic amount of base is necessary for activity; best results were obtained with Cs2CO3. 相似文献
998.
Ben Ford 《Transactions of the American Mathematical Society》1999,351(10):3869-3913
Determining the subgroup structure of algebraic groups (over an algebraically closed field of arbitrary characteristic) often requires an understanding of those instances when a group and a closed subgroup both act irreducibly on some module , which is rational for and . In this paper and in Overgroups of irreducible linear groups, I (J. Algebra 181 (1996), 26-69), we give a classification of all such triples when is a non-connected algebraic group with simple identity component , is an irreducible -module with restricted -high weight(s), and is a simple algebraic group of classical type over sitting strictly between and .
999.
The distributed roughness theory of the origins of spectral periodicity in stimulus frequency otoacoustic emissions (SFOAEs) predicts that the spectral period will be altered by suppression of the traveling wave (TW) [Zweig and Shera, J. Acoust. Soc. Am. 98, 2018-2047 (1995)]. In order to investigate this effect in more detail, simulations of the variation of the spectral period under conditions of self-suppression and two-tone suppression are obtained from nonlinear cochlear models based on this theory. The results show that during self-suppression the spectral period is increased, while during high-side two-tone suppression, the period is reduced, indicating that the detailed pattern of disruption of the cochlear amplifier must be examined if the nonlinear behavior of SFOAEs is to be understood. The model results suggest that the SFOAE spectral period may be sensitive to changes in the state of the cochlear amplifier. A companion paper [Lineton and Lutman, J. Acoust. Soc. Am. 114, 871-882 (2003)] presents experimental data which are compared with the results of the above models with a view to testing the underlying theory of Zweig and Shera. 相似文献
1000.
A model for estimating the spectral period of stimulus frequency otoacoustic emissions (SFOAEs) is presented. The model characterizes the frequency spectrum of an SFOAE in terms of four parameters which can be directly related to cochlear mechanical quantities featuring in the theory of SFOAE generation proposed by Zweig and Shera [J. Acoust. Soc. Am. 98, 2018-2047 (1995)]. The results of applying the parametric model to SFOAEs generated by cochlear models suggest that it gives a sensitive measure of spectral period. It is concluded that the parametric model may be a useful tool for detecting small changes in cochlear function using SFOAE measurements. 相似文献