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排序方式: 共有1091条查询结果,搜索用时 15 毫秒
961.
Masato Kikuchi 《Mathematische Zeitschrift》2010,265(4):865-887
Let ${\Phi : \mathbb{R} \to [0, \infty)}Let
F: \mathbbR ? [0, ¥){\Phi : \mathbb{R} \to [0, \infty)} be a Young function and let
f = (fn)n ? \mathbbZ+{f = (f_n)_n\in\mathbb{Z}_{+}} be a martingale such that F(fn) ? L1{\Phi(f_n) \in L_1} for all
n ? \mathbbZ+{n \in \mathbb{Z}_{+}} . Then the process
F(f) = (F(fn))n ? \mathbbZ+{\Phi(f) = (\Phi(f_n))_n\in\mathbb{Z}_{+}} can be uniquely decomposed as F(fn)=gn+hn{\Phi(f_n)=g_n+h_n} , where
g=(gn)n ? \mathbbZ+{g=(g_n)_n\in\mathbb{Z}_{+}} is a martingale and
h=(hn)n ? \mathbbZ+{h=(h_n)_n\in\mathbb{Z}_{+}} is a predictable nondecreasing process such that h
0 = 0 almost surely. The main results characterize those Banach function spaces X such that the inequality ||h¥||X £ C ||F(Mf) ||X{\|{h_{\infty}}\|_{X} \leq C \|{\Phi(Mf)} \|_X} is valid, and those X such that the inequality ||h¥||X £ C ||F(Sf) ||X{\|{h_{\infty}}\|_{X} \leq C \|{\Phi(Sf)} \|_X} is valid, where Mf and Sf denote the maximal function and the square function of f, respectively. 相似文献
962.
S. Nakajima M. Kikuchi T. Oku N. Kobayashi T. Suzuki K. Nagase K. Hiraga Y. Muto Y. Syono 《Physica C: Superconductivity and its Applications》1989,160(5-6):458-460
Superconductivity was observed in La substituted Tl2Ba2CuO6. Both Tc and unit cell dimension, a, increase with increasing La concentration, indicating that an over-doping state in Tl2Ba2CuO6, which was due to charge transfer Tl3−t-(Cu-O)p as supported from XPS measurements, was relieved by La substitution for Ba. 相似文献
963.
K. Fukamichi M. Kikuchi S. Arakawa T. Masumoto T. Jagielinski K.I. Arai N. Tsuya 《Solid State Communications》1978,27(4):405-407
Amorphous Fe100-xBx(11.5 ≦ x ≦ 22) alloys having the invar characteristics were prepared by a single roller quenching method to investigate the magneto-volume effect. Forced volume magnetostriction, ?ω/?H, increased remarkably with decreasing boron content and the maximum value obtained was about 90 × 10?10 Oe?1 at 11.5 at.% boron. The estimated value of the pressure dependence of the Curie temperature, ?Tc/?P, was considerably large, being comparable to those of crystalline FeNi invar alloys. The ?Tc/?P curve plotted as a function of Tc approximately fitted Wohlfarth's expression. 相似文献
964.
Hideo Fujikake Kuniharu Takizawa Hiroshi Kikuchi Takanori Fujii Masahiro Kawakita Minori Yokozawa 《Optical Review》1996,3(2):89-95
A new storage-type spatial light modulator has been developed which uses a polymer-dispersed phase-transition liquid crystal film and a photoconductor for high-brightness projection displays. The liquid crystal film containing micrometer-sized chiral nematic liquid crystal domains subdivided by a unique honeycomb polymer network functions as a memory layer for an input image. The liquid crystal domains independently maintain the binary alignment states in the opaque (light-scattering) cholesteric phase or transparent nematic phase. Grayscale images can be displayed according to the spatial distribution of the bistable liquid crystal domains. The device exhibits rapid response of a few ms and a limiting resolution of 32 lp/mm. It has the advantages of high transmittance without polarizers and ease of fabrication due to the free-standing liquid crystal film. 相似文献
965.
966.
Hiroshi Abe Hirotsugu Kikuchi Kenji Hanabusa Takashi Kato Tisato Kajiyama 《Liquid crystals》2003,30(12):1423-1431
Liquid crystalline composite gels consisting of a low molecular mass gelator and a low molecular mass liquid crystal were prepared by two types of gelation method (continuous cooling and isothermal gelating), which provide different molecular self-assembling kinetics of the low molecular mass gelator as gelation proceeds. Optical microscopy and atomic force microscopy revealed that numerous fine strands of the one-dimensionally assembled low molecular mass gelators were formed in the composite gels for both the continuous cooling method and the isothermal gelating method. However, the thinner strands were more homogeneously dispersed in the isothermal gelation product at an appropriate temperature, than in the continuous cooling process. This difference in dispersion state of the strands was shown (by polarizing optical microscopy) to have a significant influence on the molecular alignment of the low molecular mass liquid crystal in the liquid crystalline composite gel. The electro-optical response and light scattering-transmitting switching, of the liquid crystalline composite gel in an applied electric field was extremely dependent on the morphology of the gelators. High contrast light switching was achieved for the composite prepared by isothermal gelation. The response time of electro-optical switching was less than 100 µs under 30 Vrms. 相似文献
967.
The transient absorption of an intermediate R which is formed from an excited state higher than the lowest triplet state was observed in an ethanol solution of 4,5′,8-trimethylpsoralen (TMP). The temperature effects on the fluorescence yield φF for TMP and on the initial absorbance DR of R were studied and it was found that DR increases with increasing temperature whereas φF decreases. These results indicate that a photochemical reaction plays an important role on the deactivation of TMP in the excited singlet state 相似文献
968.
969.
970.
Masato Hoshi Koichi Kikuchi Hiroshi Kokubun 《Journal of photochemistry and photobiology. A, Chemistry》1987,41(1)
The rate constants and the radical yields for the hydrogen-atom transfer reaction from four monohalogenated phenols to triplet 7,8-benzoquinoline were determined by an emission—absorption flash technique. The rate constants are of the order of 109 M−1 s−1 except for 2-bromophenol, and the radical yield Φrt decreases on halogen substitution. In the case of monobromophenols, Φrt is sensitive to the position of the bromine atom. The rate constant of free radical recombination increases with decreasing Φrt. Such heavy-atom effects are explained in terms of the heavy-atom-induced spin relaxation of the triplet radical pair. 相似文献