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611.
612.
Kaoru Yoneda 《Acta Mathematica Hungarica》2004,102(3):261-267
Let ξ =(ξ0,ξ1,...) be a zero-one series. We shall study whether the Walsh series,
is the Walsh--Fourier series of some measure or not.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
613.
A phase-separated acidic ionic liquid affords to catalyze a reaction of pyrrole with benzaldehyde in dichloromethane, forming porphyrins in a comparable yield to the Lindsey method and is reusable at least ten times without loss of catalytic activity. 相似文献
614.
Uchiyama S Kawai N de Silva AP Iwai K 《Journal of the American Chemical Society》2004,126(10):3032-3033
We illustrate a general polymeric design of fluorescent logic gates, for example, AND, using temperature and pH as inputs. 相似文献
615.
Five new alkaloids, dictyodendrins A-E (1-5), were isolated from the Japanese marine sponge Dictyodendrilla verongiformis as telomerase inhibitors. Their structures were elucidated by spectroscopic and chemical methods. Dictyodendrins are tyramine-based pyrrolocarbazole derivatives containing three or four p-hydroxybenzene groups. They inhibited telomerase completely at a concentration of 50 microg/mL. 相似文献
616.
Masashi Jimbo Tomohiro Fukada Hiromi Takeda Fuminao Suzuki Kaoru Horino Kiyohito Koyama Susumu Ikeda Yasaku Wada 《Journal of Polymer Science.Polymer Physics》1986,24(4):909-921
Ferroelectric polarization-reversal switching of vinylidene fluoride—trifluoroethylene copolymer with 73 mol % of vinylidene fluoride is investigated under a variety of conditions in an attempt to derive detailed information on the polarization reversal of the polymer. The electric-field dependence of switching time ts obeys an exponential law. The temporal change of switching current density J is presented in the form J/(Ps ? P) versus time (P is the polarization, and Ps is its saturation value), which is free of the depolarization-field effect and discriminates in a straightforward manner between acceleration and deceleration of switching. Effects of the annealing of samples upon ts are observed together with changes in the degree of crystallinity. Effects of space charge distribution upon ts are investigated by applying two successive pulses, positive and negative, with varied intervals tw between the two. The dynamics of space charge redistribution is elucidated from the tw dependence of the ts of the second pulse. The temperature dependence of ts indicates that the switching becomes critically fast as the phase-transition temperature is approached. 相似文献
617.
Masayuki Kuzuya Fumio Miyake Kaoru Kamiya Takachiyo Okuda 《Tetrahedron letters》1982,23(25):2593-2596
MO quantities by CNDO/2 method on several valence isomeric ketenes and structurally corresponding allene molecules were calculated to evaluate the influence of structural feature on magnitude of back-donation of oxygen n-electrons in ketene, and to rationalize an unusual cycloaddition involved in diphenyl ketene. 相似文献
618.
Grignard reagents react with acid chlorides in tetrahydrofuran at low temperature to produce ketones in excellent yields. The results reported here strongly indicate the importance of the solvent in Grignard reagent chemistry. 相似文献
619.
Plasma-induced reaction in an aqueous solution of phenyl-containing amino acids resulted in the formation of several hydroxyphenyl amino acids, which was explained by the action of hydroxyl radicals generated by decomposition of water molecules by the high energy plasma. 相似文献
620.
Fuzzy control algorithms are developed based on fuzzy models of systems. The control issues are posed as multiobjective optimization problems involving goals and constraints imposed on system's variables. Two basic design modes embrace on- and off-line modes of control development. The first type of design deals with the time and state-dependent objectives and pertains to control determination based upon the current state of the fuzzy model. The second design mode gives rise to an explicit form of a fuzzy controller that is learned based on a given list of state-control associations. Both the fuzzy models as well as fuzzy controllers are realized as logic processors. 相似文献