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991.
The fixed point property for multivalued nonexpansive mappings 总被引:1,自引:0,他引:1
T. Domínguez Benavides 《Journal of Mathematical Analysis and Applications》2007,328(2):1471-1483
We show some properties concerning geometrical constants of Banach spaces which imply the existence of fixed points for multivalued nonexpansive mappings and we study the relationship between these properties. 相似文献
992.
O. V. Il’in 《Journal of Mathematical Sciences》2007,141(1):1041-1047
We describe W-geometry of two-dimensional Toda systems associated with the Lie algebra C
n
.
__________
Translated from Fundamental’naya i Prikladnaya Matematika (Fundamental and Applied Mathematics), Vol. 11, No. 1, Geometry,
2005. 相似文献
993.
The interaction between gene activation and cellular activity has recently emerged as a critical aspect of brain behavior, but the dynamics of networks incorporating these interactions are poorly understood. An interesting phenomena arises when the genetic activation oscillates endogenously and a network of such cells synchronize to a coherent rhythm, such as is the case with the suprachiasmatic nucleus. To explain this synchronization, we propose a model in which a mRNA/protein expression cycle drives neurons electrical activity, and synaptic activation shifts the phase of the protein rhythm. Using lattice networks, we demonstrate that these interactions are sufficient to generate coherent oscillation. © 2006 Wiley Periodicals, Inc. Complexity 12: 67–72, 2006 相似文献
994.
V. V. Platonov A. A. Khadartsev A. Yu. Shvykin D. V. Prokopchenkov V. A. Proskuryakov T. V. Chestnova 《Russian Journal of Applied Chemistry》2006,79(10):1581-1587
The organic matter of schungite rock from the Zazhogino Deposit of Karelian Transonega region was extracted in the sequential mode. The extract composition was determined by several modern physicochemical methods. 相似文献
995.
S. A. Andronati A. A. Krys’ko B. M. Chugunov T. A. Kabanova A. G. Artemenko 《Russian Journal of Organic Chemistry》2006,42(8):1174-1182
A new series of RGDF mimetics, derivatives of 4-(isoindolin-5-yl)amino-4-oxobutanoic acid, was synthesized. The compounds obtained inhibit efficiently the thrombocytes aggregation in experiments in vitro; their biological targets are fibrinogen receptors. The antiaggregatory activity and the affinity correlate with the hydrophobicity of the compounds. 相似文献
996.
Role of readily hydrolyzable polysaccharides of larch wood in production of board materials is studied. 相似文献
997.
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
998.
In this article, composite nanofibers of poly(ε-caprolactone) (PCL) with iron–platinum (FePt) nanoparticles were successfully fabricated via coaxial electrospinning. The structure and morphology of FePt/PCL composite nanofibers were observed using transmission electron microscope and scanning electron microscope, respectively. The magnetic behavior of FePt/PCL composite nanofibers was investigated by alternating gradient magnetometer at room temperature. 相似文献
999.
Meihua Lu H. Gong T. Song Jian-Ping Wang Hong-Wei Zhang T.J. Zhou 《Journal of magnetism and magnetic materials》2006
We present a simple way to synthesize FePt and ZnO (wide-band-gap semiconductor) nanoparticle composites. The FePt nanoparticles were fabricated using the method reported by Sun et al. By controlling the heating rate, 3 nm FePt nanoparticles were synthesized. Well-dispersed FePt and ZnO nanoparticle composites were prepared by further adding zinc acetate and oleyl amine into the 3 nm FePt nanoparticle dispersion. By controlling the molar ratio of the FePt and zinc acetate, FePt and ZnO nanoparticle composites with different FePt particle fractions were obtained. The intensity of photo luminescence spectra of the nanoparticle composites increases very much with decreasing FePt particle fraction, whereas the peak position shifts a little. After annealing at 550 °C for half an hour, the nanoparticle composites become magnetically hard or semi-hard with coercivity much dependent on the FePt particle volume fraction. The coercivity of the composites increases with annealing temperature. The composites hold the promise of applications in new generation recording and/or optical devices. 相似文献
1000.
Nickel and cobalt films illustrate alternative Bloch lines with cap switches. The strip magnetic domains become zigzag and bubbling cells for Ni and Co films, respectively, under an external field of 1.5 T. The magnetoresistances (MR) for currents parallel (CIW) to the domain walls is 15% less than those of the perpendicular (CPW) case. We also studied the magneto size effect by applying the magnetic field normal to the surface, from which the Sondheimer oscillation appears attributing to periodic striking of the surface for electrons traveling in circular motion on a plane canting to the surface. The experiments can be expressed by the magneto size effect inherited with very small specularity parameters. 相似文献