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101.
J. D. Brock D. Y. Noh B. R. McClain J. D. Litster R. J. Birgeneau Amnon Aharony P. M. Horn Jason C. Liang 《Zeitschrift für Physik B Condensed Matter》1989,74(2):197-213
In this paper, we report results from synchrotron X-ray scattering studies of thefluid/hexactic/solid phases and phase transitions in both very thick and very thin, freely suspended films of tilted hexatic liquid crystals. Contrary to the thick film case, the higher Fourier coefficients describing the bond orientational order are suppressed in very thin films. This suppression is consistent with a two-dimensional bond orientational order parameter,
6, rather than the three-dimensional bond orientational order parameter found in very thick films. For a film containing twently-three (23) smectic layers we find that
6 is two-dimensional whereas the positional order in the crystallineS
J phase is three-dimensional. We present an analysis of the thick film data in terms of the three-dimensionalXY-model and a new mean field theory model which incorporates explicitly the quasi two-dimensional nature of bulk smectic phases. 相似文献
102.
103.
ABSTRACTClusters of planar-aligned short-pitch cholesteric liquid crystal spheres generate dynamic colourful patterns due to multiple selective reflections from the radially oriented cholesteric helices in neighbour shells at varying distances. These photonic communication patterns were widely investigated for the cases of both droplets and shells, demonstrating not only intriguing optical phenomena but also potential for applications as new optical elements for photonics, sensing or security pattern generation. However, the optics of these clusters is truly complex and until now only the strongest and most fundamental reflections have been analysed and explained. In this report, we elucidate the origin of a number of more subtle reflections and we explain the extension in space of various spots as well as their internal colour variations. 相似文献
104.
105.
106.
Su Jung Noh Yasuyoshi Miyamoto Naoto Hayashi Ji Sung Lee Young Keun Kim 《Solid State Communications》2012,152(12):1004-1007
Magnetic domain wall behaviors in CoPt nanowires consisting of multiple pairs of notches were investigated by experimental measurements as well as by micromagnetic modeling. The nanowires were fabricated by ion-beam sputter deposition and e-beam lithography where one to three triangular shaped notches were installed at an interval of 1 μm. Based on the evaluated I–V characteristics, we observed that differential resistance curves showed two peaks with a local minimum at around zero current; the domain wall was trapped between the current ranges within these two peaks. As the number of notch was increased, the resistance of the nanowire became larger. 相似文献
107.
108.
Keumhan Noh Kwang‐il Kwon Tae Cheon Jeong Wonku Kang 《Biomedical chromatography : BMC》2010,24(11):1199-1202
Sparfloxacin, a fluoroquinolone antibiotic, is used for the treatment of bacterial infection. A quantification method using mass spectrometry was developed for the determination of sparfloxacin in rat plasma. After simple protein precipitation with acetonitrile, the analytes were chromatographed on a reversed‐phase C18 column and detected by liquid chromatography/tandem mass spectrometry with electrospray ionization. The accuracy and precision of the assay were in accordance with FDA regulations for validation of bioanalytical methods. This method was applied to measure the plasma sparfloxacin concentrations after a single oral administration of sparfloxacin in rats. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
109.
Yoon Shon Sejoon Lee Tae Won Kang Youngmin Lee Seung-Woong Lee Jin Dong Song Hyung-Jun Kim Jeong Ju Lee Im Taek Yoon 《Journal of Crystal Growth》2010,312(14):2069-2072
The p-type InMnP:Be epilayers, which were prepared by thermal diffusion of Mn through in-situ deposition of Mn layer using molecular beam epitaxy (MBE) onto MBE-grown InP:Be epilayers and subsequent in-situ annealing at 300–350 °C, were investigated. InMnP:Be epilayers prepared by the above sequence clearly showed the Mn-related emission band at 1.1–1.2 eV, which indicates the effective incorporation of Mn2+ ions into the host layer InP:Be. The samples demonstrated very large ferromagnetic hysteresis loops with enhanced coercivity, and the ferromagnetic-to-paramagnetic transition of the samples was observed to occur at ∼85 K. These results suggest that InP-based ferromagnetic semiconductor layers having enhanced ferromagnetism can be effectively formed by the above-mentioned sequential in-situ processes. 相似文献
110.
The dynamics of a tachyon attached to a Dvali, Gabadadze and Porrati (DGP) brane is investigated. Exponential potential and inverse power law potential are explored, respectively. The quasi-attractor behavior, for which the universe will eventually go into a phase similar to the slow-roll inflation, is discovered in both cases of exponential potential and inverse power law potential. The equation of state (EOS) of the virtual dark energy for a single scalar can cross the phantom divide in the branch θ=−1 for both potentials, while the EOS of the virtual dark energy for a single scalar cannot cross this divide in the branch θ=1. 相似文献