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921.
922.
M. S. Kalinin M. B. Krainev 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(7):984-987
The behavior of the intensity of anomalous and galactic cosmic rays in the outer heliosphere is compared. The previous hypothesis, according to which the lowest energy galactic cosmic rays affected by large-scale electric fields far beyond the termination shock wave of the solar wind may contribute to the behavior of the anomalous component intensity, is analyzed. 相似文献
923.
We exhibit a family of homogeneous hypersurfaces in affine space, one in each dimension, that generalize the Cayley surface. 相似文献
924.
The electronic structure of single-walled carbon nanotubes was experimentally investigated using x-ray photoelectron spectroscopy, reflection electron energy-loss spectroscopy, and Auger electron spectroscopy. A shake-up satellite structure observed near the C 1s core-level lines in the x-ray photoelectron spectra at high binding energies in the range 284–330 eV due to excitation of π and π + σ plasmons was studied. The effect of irradiation by 1-keV argon ions on the shape of the spectra was analyzed. The shape of the C 1s satellite spectra was found to be sensitive to Ar+ irradiation in the electron energy loss range 10–40 eV corresponding to excitation of π + σ plasmons. Auger spectroscopy revealed the presence of argon on the surface of ion-irradiated samples. The argon content increased to ~4 at. % with increasing irradiation dose. An analysis of the results obtained and their comparison with the data available in the literature led to a qualitative conclusion that the bond angles of the carbon atoms making up the walls of single-walled carbon nanotubes are distorted at sites exposed to Ar+ irradiation. 相似文献
925.
A. F. Semenchev V. G. Gavrilyachenko E. M. Kuznetsova E. N. Sklyarova 《Physics of the Solid State》2006,48(6):1146-1148
The details of the mechanical effects (twinning and microcracking) are clarified at various stages of dynamic fatigue of PbTiO3 crystals using a polarization microscope and selective etching. 相似文献
926.
Fractal Gaussian models have been widely used to represent the singular behavior of phenomena arising in different applied fields; for example, fractional Brownian motion and fractional Gaussian noise are considered as monofractal models in subsurface hydrology and geophysical studies Mandelbrot [The Fractal Geometry of Nature, Freeman Press, San Francisco, 1982 [13]]. In this paper, we address the problem of least-squares linear estimation of an intrinsic fractal input random field from the observation of an output random field affected by fractal noise (see Angulo et al. [Estimation and filtering of fractional generalised random fields, J. Austral. Math. Soc. A 69 (2000) 1-26 [2]], Ruiz-Medina et al. [Fractional generalized random fields on bounded domains, Stochastic Anal. Appl. 21 (2003a) 465-492], Ruiz-Medina et al. [Fractional-order regularization and wavelet approximation to the inverse estimation problem for random fields, J. Multivariate Anal. 85 (2003b) 192-216]. Conditions on the fractality order of the additive noise are studied to obtain a bounded inversion of the associated Wiener-Hopf equation. A stable solution is then obtained in terms of orthogonal bases of the reproducing kernel Hilbert spaces associated with the random fields involved. Such bases are constructed from orthonormal wavelet bases (see Angulo and Ruiz-Medina [Multiresolution approximation to the stochastic inverse problem, Adv. in Appl. Probab. 31 (1999) 1039-1057], Angulo et al. [Wavelet-based orthogonal expansions of fractional generalized random fields on bounded domains, Theoret. Probab. Math. Stat. (2004), in press]). A simulation study is carried out to illustrate the influence of the fractality orders of the output random field and the fractal additive noise on the stability of the solution derived. 相似文献
927.
Preparation and mechanical properties of layers made of recombinant spider silk proteins and silk from silk worm 总被引:1,自引:0,他引:1
F. Junghans M. Morawietz U. Conrad T. Scheibel A. Heilmann U. Spohn 《Applied Physics A: Materials Science & Processing》2006,82(2):253-260
Layers of recombinant spider silks and native silks from silk worms were prepared by spin-coating and casting of various solutions.
FT-IR spectra were recorded to investigate the influence of the different mechanical stress occurring during the preparation
of the silk layers. The solubility of the recombinant spider silk proteins SO1-ELP, C16, AQ24NR3, and of the silk fibroin
from Bombyx mori were investigated in hexafluorisopropanol, ionic liquids and concentrated salt solutions. The morphology and thickness of
the layers were determined by Atomic Force Microscopy (AFM) or with a profilometer. The mechanical behaviour was investigated
by acoustic impedance analysis by using a quartz crystal microbalance (QCMB) as well as by microindentation.
The density of silk layers (d<300 nm) was determined based on AFM and QCMB measurements. At silk layers thicker than 300 nm
significant changes of the half-band-half width can be correlated with increasing energy dissipation. Microhardness measurements
demonstrate that recombinant spider silk and sericine-free Bombyx mori silk layers achieve higher elastic penetration modules EEP and Martens hardness values HM than those of polyethylenterephthalate (PET) and polyetherimide (PEI) foils. 相似文献
928.
We investigate the dependence of the relaxation time of the current flowing in a nematic cell submitted to an external dc voltage on the physical properties of the substrate. We show that previously presented analyses of the same problem are not very useful for practical applications. We compare our theoretical predictions with experimental data, and show that the agreement is rather good. The influence of the adsorption-desorption phenomenon on the relaxation time is also discussed. 相似文献
929.
A palladium‐TPPTS catalyst heterogenized on KF/alumina has been shown to be effective and recyclable for the selective formation of monooctadienylxylopyranosides via the telomerization of butadiene with D ‐xylose. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
930.