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991.
Under some mild conditions, we establish a strong Bahadur representation of a general class of nonparametric local linear M-estimators for mixing processes on a random field. If the socalled optimal bandwidth hn = O(|n|^-1/5), n ∈ Z^d, is chosen, then the remainder rates in the Bahadur representation for the local M-estimators of the regression function and its derivative are of order O(|n|^-4/5 log |n|). Moreover, we derive some asymptotic properties for the nonparametric local linear M-estimators as applications of our result. 相似文献
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995.
Chen Guang Xu Bai Qiang Xu Gui Dong Xu 《Applied Physics A: Materials Science & Processing》2011,105(2):379-386
A model based on the theory of fluid–structure interaction is developed to simulate the laser thermoelastic generation and
propagation of Leaky Lamb waves at the water–aluminum interface. Each component of displacement, stress, and temperature are
derived in transform domain by the photothermoelastic transfer matrix method. The time domain solutions are obtained by numerically
inverting the transforms while the dispersion curves and attenuation curves for the leaky waves are also calculated. Then
the propagation characteristics of different modes are analyzed. The model establishes a quantitative relation between the
laser parameters, the material parameters, the corresponding waveforms, and the dispersion curves, which provides a useful
tool for the Leaky Lamb waves applied to nondestructive evaluation. 相似文献
996.
Yan-Qiu Deng Zhen-Wei Zhang Ya-Hui Feng Albert S.C. Chan Gui Lu 《Tetrahedron: Asymmetry》2012,23(24):1647-1652
An effective asymmetric synthesis of optically active 1,3-dinitro compounds via the direct Michael addition of nitroalkanes onto nitroalkenes has been described. In the presence of readily modified cinchona alkaloid derivatives, nitroethane reacted well with a variety of aromatic and heterocyclic aromatic nitroalkenes to afford products with good diastereoselectivities (dr up to 72/28) and enantioselectivities (ee up to 94%). The catalyst loading can be decreased to 2 mol % without compromising the asymmetric induction or the reaction rate. 相似文献
997.
Let
$$\mathcal{H}$$ 相似文献
998.
In this work it was presented an application of task specific onium salt as soluble support for the synthesis of 3-amino-5-aryl-2,5- dihydropyridazines.This soluble support is of wide applicability and combines advantages of solid phase synthesis without its limitations with those of solution phase chemistry.After a simple washing step,products were cleaved from the supports and obtained in good yields. 相似文献
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1000.
A Lewis acidic ionic liquid, [bmim][FeCl4], was employed to catalyze acetylation of alcohols and phenols, and the conversion of aldehydes to corresponding 1,1‐diacetates without conventional organic solvents. The catalyst is easily available, water‐tolerant, recoverable and easy to handle. 相似文献