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1.
By extracting combinatorial structures in well-solved nonlinear combinatorial optimization problems, Murota (1996,1998) introduced the concepts of M-convexity and L-convexity to functions defined over the integer lattice. Recently, Murota–Shioura (2000, 2001) extended these concepts to polyhedral convex functions and quadratic functions in continuous variables. In this paper, we consider a further extension to more general convex functions defined over the real space, and provide a proof for the conjugacy relationship between general M-convex and L-convex functions.Mathematics Subject Classification (1991): 90C10, 90C25, 90C27, 90C35This work is supported by Grant-in-Aid of the Ministry of Education, Culture, Sports, Science and Technology of Japan 相似文献
2.
We report on the simultaneous generation of phase-conjugate signals by degenerate four-wave mixing (DFWM) and holographic processes using a nanosecond pulse and a CW lasers in polyvinyl alcohol (PVA) films doped with four kinds of saturable absorbing dyes. For the pulse laser, of the four kinds of dye-doped PVA films, the erythrosine B-doped PVA and uranine doped-PVA films generate PC signals only by the DFWM process, while the other dye-doped PVA films generate PC signals simultaneously by not only the DFWM process but also the holographic process. Especially, the safranin T-doped PVA film generates strong PC signals by the holographic process. In contrast, all of the dye-doped PVA films generate the two types of PC signals for the CW laser. The fading of dye molecules is found to result in the generation of the holographic component of PC signals which governs the temporal behavior of the total PC signals. 相似文献
3.
Teruhisa Horita Katsuhiko Yamaji Natsuko Sakai Yueping Xiong Harumi Yokokawa Tatsuya Kawada 《Ionics》2002,8(1-2):108-117
The oxygen reduction active sites were visualized around the O2/SOFC cathode/electrolyte triple phase boundaries (TPB) by the16O/18O exchange techniques and secondary ion mass spectrometry (SIMS) analysis. The higher18O concentration is observed on the cathode top surfaces (La0.9Sr0.1MnO3-mesh, Au-mesh, and Ag-porous), which suggested the promotion of oxygen adsorption and oxygen surface exchange at the cathode.
The oxygen diffusion through the bulk of cathode occurred at the La0.9Sr0.1MnO3-mesh and the Ag-porous cathodes, not at the Au-mesh cathode. On the YSZ surfaces after removing the cathode, the active sites
for oxygen incorporation were analyzed by SIMS. The active sites for oxygen incorporation were at the La0.9Sr0.1MnO3/YSZ interface as well as the TPB. On the other hand, the active sites for oxygen incorporation are limited to the TPB in
the case of the Au-mesh removed YSZ surface. From the SIMS analysis, the expansion of the active sites for oxygen incorporation
is less than a few μm from the TPB lines.
Paper presented at the 8th EuroConference on Ionics, Carvoeiro, Algarve, Portugal, Sept. 16–22, 2001. 相似文献
4.
A cyanine dye, 2-[7-(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)-1,3,5-heptatrienyl]-1,3,3-trimethyl-3H-indolium iodide (NK-125), is doped in 4-cyano-4'-pentylbiphenyl (5 CB), and the mixture is sandwiched between two pieces of rubbed glass plates. The third-order nonlinear optical properties of the oriented NK-125-SCB layers are measured by the resonant femtosecond degenerate four-wave mixing (DFWM) technique at 760 nm. The third-order nonlinear optical susceptibility of one of the present samples is 5.5×10^-8 esu. The slow DFWM response of the NK-125-SCB layers due to a population grating is accelerated by the increasing laser power because of amplified spontaneous emission (ASE). On the other hand, we do not observe a similar phenomenon for NK-125- polyethylene glycol (PEG-400). Oriented NK-125 molecules in nematic liquid crystals must have very high ASE efficiency. Hence the population grating in a DFWM signal disappears within about 4 ps. It is expected that NK-125-SCB can be used as a material for very fast all-optical switching. 相似文献
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Abstract— A new method of using hydroxylamine as the reagent was developed to determine the concentrations of chlorophylls a and b in plant extracts accurately and sensitively. The method is based on the principle that hydroxylamine reacts in a short time with the aldehyde group of chlorophyll b in 95 per cent methanol at pH 5.8 to afford a derivative having a red band similar in position to the red band of chlorophyll a , while the spectrum of chlorophyll a is unaffected by the treatment with hydroxylamine. The method includes the measurements of absorbanlce for the mixture of a plant extract with hydroxylamine and for the reagent blank at a single wavelength, 666 mμ, and the concentrations of chlorophylls a and b are calculated from the absorbance value for the reagent blank and the increment of absorbance due to the reaction. By measuring this increment directly by difference photometry, one can determine a low concentration of chlorophyll b relative to chlorophyll a . The contents of chlorophylls in matured and etiolated leaves were determined by the method, and the errors included in this method were shown to be smaller than those in a commonly used technique including the measurements at two different wavelengths. 相似文献
9.
Synthesis and structures of the title compounds 2a–d are described. In spite of non-parallel orientation of the two base rings, fairly large hypochromism was observed for 2a–d. 相似文献
10.
The hydrothermal syntheses of the alkali metal molybdenum bronzes from starting solids (HxMoO3) with structural affinities to the desired products were investigated. Single-phase potassium blue and red bronzes were prepared by the hydrothermal treatments at around 430 K, and characterized by powder X-ray diffraction, IR spectroscopy, and SEM. The formation processes of these two bronzes during the hydrothermal treatments were found to differ. The blue bronze was formed by a structure-inheriting solid-state route from HxMoO3 with x<0.3, whereas the red bronze was formed for x>0.3 through a solution dissolution/deposition route via the formation of MoO3+MoO2. 相似文献