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991.
Gabriel S Duwez AS Jérôme R Jérôme C 《Langmuir : the ACS journal of surfaces and colloids》2007,23(1):159-161
Thermoresponsive brushes have been efficiently grafted onto (semi)conductive surfaces by a two-step process. In the first step, poly(N-succinimidyl acrylate) chains have been chemisorbed onto silicon or stainless steel by the electrografting method. Then, these modified electrodes were immersed in isopropylamine in order to transform the grafted chains to the thermoresponsive poly(N-isopropyl acrylamide). The thermal response of these brushes has been shown by AFM. This straightforward grafting process is quite attractive for surface modification in confined media and is thus promising for microfludics application. 相似文献
992.
Jeffrey L. Meyer 《The Ramanujan Journal》2007,14(1):79-88
This paper considers a generalization of an integral introduced by S. Ramanujan in his third notebook. Ramanujan’s integral
is itself a version of the dilogarithm,
We prove various functional equations and properties of the generalized integral.
2000 Mathematics Subject Classification Primary–33B30 相似文献
993.
Track assignment 总被引:1,自引:0,他引:1
994.
In many particle methods the accurate interpolation of a velocity field represented on a computational grid to arbitrary positions is crucial [2, 5]. Here, the importance of mass conservation and order of the interpolation scheme were analyzed. Initially equally distributed particles were tracked in a stationary, incompressible 2d flow field using different interpolation schemes. It could be demonstrated that especially mass conservation is of great importance, in particular in the case of complex flow patterns. The ideas presented in this paper are more general and the methods can be extended for unsteady, compressible 3d flow problems. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
995.
996.
997.
We investigate the single-impurity Anderson model by means of the recently introduced modified perturbation theory. This approximation scheme yields reasonable results away from the symmetric case. The agreement with exactly known results for the symmetric case is checked, and results for the non-symmetric case are presented. With decreasing conduction band occupation, the breakdown of the screening of the local moment is observed. In the crossover regime between Kondo limit and mixed-valence regime, an enhanced zero-temperature susceptibility is found. 相似文献
998.
The TeV γ-ray sky displays at this time 9 sources comprising 6 supernova remnants (SNR) and 3 active galactic nuclei (AGN). They have been discovered with AIR
ERENKOV TELESCOPES since 1989, and more sources are sure to be found. They are related to violent astrophysical events and promise to be used as unique tools for cosmological questions like the universal infrared photon field and the intergalactic magnetic field strength. 相似文献
999.
M. Makrocka-Rydzyk S. Glowinkowski S. Jurga W. H. Meyer 《Applied magnetic resonance》2000,18(1):63-70
Proton and fluorine second moment and spin-lattice relaxation timesT 1 andT lρ have been employed to study molecular dynamics in the comb-like I-6,6-16-Me-BF4 ionene in the temperature range from 110 up to 300 K. The existence of motions of methyl groups, trans-gauche isomerization, and/or rotation of the main- and side-chain méthylene groups, as well as isotropic reorientation of tetrafluoroborate ions were established. The observed relaxation behaviors are explained by motional models which assume Davidson-Cole asymmetrical distribution of correlation times. The best-fit motional parameters are given. 相似文献
1000.
P. Bakule P.E.G. Baird M.G. Boshier S.L. Cornish D.F. Heller K. Jungmann I.C. Lane V. Meyer P.H.G. Sandars W.T. Toner M. Towrie J.C. Walling 《Applied physics. B, Lasers and optics》2000,71(1):11-17
A Q-switched alexandrite laser suitable for high-resolution spectroscopy is described which produces pulses of 35 mJ energy in a 10 MHz bandwidth, with a high-purity TEM00 mode. The laser can be synchronised to external event to within 100 ns. The output pulse length is 120 ns and the repetition rate 25 Hz. The laser is injection-seeded by a Ti:sapphire laser operating around 730 nm. To preserve single-mode seeding under external triggering conditions, and to obtain small time-jitter, active cavity length control was used. In order to achieve the 10 MHz output bandwidth, intra-cavity electro-optic modulators were used to compensate for the frequency chirp. The refractive index of alexandrite was found to vary linearly with inversion density with a constant of proportionality equal to 1.6᎒-24 cm3. In pulsed operation at 730 nm, the index change due to this effect is only partially compensated by changes due to ground state phonon relaxation. 相似文献