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991.
The field-theoretic approach to critical phenomena is extended to deal with critical dynamics far from equilibrium. In particular, the macroscopic evolution equation for the average order parameter is derived in a manner parallel to the derivation of the equation of state. The method is illustrated by deriving the scaled macroscopic equation of motion for the timedependent Ginzburg-Landau model near the critical point for dimensionality near four. 相似文献
992.
993.
Hydrodynamic limit for the Ginzburg-Landau interface model was established in [6] under periodic boundary conditions. This paper studies the same problem on a bounded domain imposing Dirichlet boundary conditions. A nonlinear partial differential equation of second order with boundary conditions is derived as a macroscopic equation. The main tools are H
–1-method used in [6] and the higher integrability of gradients in [2].The author was supported by DFG project De 663/2-2 and 2/3 from April, 2001 to March, 2002, and by JSPS reserch fellowship for young scientists from April, 2002.
Mathematics Subject Classification (2000): 60K35, 82C24, 35K55 相似文献
994.
Aoki T Takei N Yonezawa H Wakui K Hiraoka T Furusawa A van Loock P 《Physical review letters》2003,91(8):080404
A continuous-variable tripartite entangled state is experimentally generated by combining three independent squeezed vacuum states, and the variances of its relative positions and total momentum are measured. We show that the measured values violate the separability criteria based on the sum of these quantities and prove the full inseparability of the generated state. 相似文献
995.
Yoshihiko Shoji Takao Asaka Hideki Dewa Hirohumi Hanaki Yoshinori Hisaoka Toshiaki Kobayashi Takahiro Matsubara Takayuki Mitsui Akihiko Mizuno Shinsuke Suzuki Tsutomu Taniuchi Hiromitsu Tomizawa Kenichi Yanagida 《Infrared Physics & Technology》2008,51(5):394-396
We have demonstrated the idea of circulating a short, intense linac bunch for some tens of turns in an isochronous ring. We compressed a bunch from the SPring-8 linac to a few picoseconds rms by means of an energy compression system and a beam transport line from the linac to NewSUBARU. The NewSUBARU storage ring was set to a quasi-isochronous condition and the bunch circulated for about 50 turns after injection while maintaining the short bunch length. At the same time, a pulse train of strong coherent synchrotron oscillation from the short bunch was observed. 相似文献
996.
997.
81Br NQR measurements of the mixed-valence compound (NH4)4SbIII SbVBr12, which has SbVBr6 ? and SbIIIBr6 3? octahedra in different oxidation states in the tetragonal pseudo-K2PtCl6 structure, were carried out by pulse method in the temperature range between 80 and 300 K. The phase transition temperature of T c = 212 K was redetermined. The T 1 values are quite different between SbVBr6 ? and SbIIIBr6 3? octahedra. For all resonance lines T 1 minima were observed at T c. The T 1 behavior at T c was explained by a softening of the rotary lattice mode around a principal axis of each octahedron along the c axis of the crystal. The distinctive feature in the temperature dependence of both 81Br NQR frequencies and T 1 values for each anion indicates that the static rotation may occur for SbVBr6 ? but not for SbIIIBr6 3? at T c in the low temperature phase. 相似文献
998.
Hiroshi Suga Emiko Koyama Hideo Tokuhisa Kyoko Fujiwara Tohru Nakamura Yasushiro Nishioka Wataru Mizutani Takao Ishida 《Surface science》2007,601(1):68-75
The adsorption process, molecular arrangement and protonation behavior of self-assembled monolayers (SAMs) of bipyridine thiol on Au(1 1 1) were investigated using X-ray photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM), with a view towards constructing a molecular ion sensor. When the bipyridine SAMs were immersed in a strong CF3SO3H solution for protonation of the bipyridine group, additional N(1s) XPS peaks were generated at higher binding peak positions where the origin of the peak was considered to be the N-H species. We further investigated the relationship between the immersion time for the SAMs and the probability of protonation. We observed a decrease in the probability of protonation with a longer immersion time for the SAMs. We consider that both the bipyridine molecular arrangements and the molecular density on the Au surface are crucial for controlling the probability of protonation based on the STM and XPS data. 相似文献
999.
1000.
A two-wavelength oscillation C02 laser was constructed for the differential absorption measurement of low concentrations of atmospheric trace molecules and pollution molecules. A diffraction grating was alternately angle-modulated for the two-branch oscillation using a single C02 laser. The output power of the two wavelengths was balanced to be equal. With these characteristics, the phase-sensitive detection technique can be applied to give highly sensitive detection of the received power difference, which is proportional to the absorption in the optical path of the transmitted beams. A differential absorption spectrometer was used to demonstrate the usefulness of this two-wavelength laser oscillation method incorporating the output power balancing technique. The concentration of ethylene molecules was detected in a calibration cell and was also measured in real time in the exhaust of a combustion engine. From these results it has been shown that this differential absorption scheme offers a minimum detectable absorption of approximately 0.8%. 相似文献