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The phonon dispersion relations of 00σT branch were measured for Ni95Pt5 and Ni70Pt30. The dispersion curves breaks up into two branches. Th general shape and its concentration dependence can be explained qualitatively by Taylor's coherent potential approximation theory. 相似文献
44.
Yoshio Teki Takeji Takui Mitsuru Hirai Koichi Itoh Hiizu Iwamura 《Chemical physics letters》1982,89(3):263-267
Optically detected ENDOR and electron—nuclear—nuclear triple resonance of 17O were measured via phosphorescence from 3(nπ*) benzil in benzophenone-d10 crystals at high magnetic field. The n and π* spin densities on the oxygen atom are 0.201 and 0.092, respectively, the angle between the two CO bonds being 150°. 相似文献
45.
Water content distribution in a polymer electrolyte membrane for advanced fuel cell system with liquid water supply 总被引:2,自引:0,他引:2
To better understand the operation of a new fuel cell design, we used magnetic resonance imaging (MRI) to measure the water content distribution in a polymer electrolyte membrane under fuel cell operation with and without a supply of liquid water. The supply of liquid water to the membrane improved the cell performance by increasing the water content in the membrane and thus reducing the electrical resistance of the membrane. The study also showed that MRI is a promising method to investigate the distribution of water in the membrane of a fuel cell under operating conditions. 相似文献
46.
Di(4-pyridyl)diazomethanes having two and four ortho chlorine groups were prepared, and the triplet carbenes generated from them were characterized by ESR and UV/vis at low temperature and time-resolved UV/vis at room temperature. An appreciable increase in the stability of triplet carbenes is achieved by introducing ortho chlorine groups. [structure: see text] 相似文献
47.
Sasaki K Sugou K Miyamoto K Hirai J Tsubouchi S Miyasaka H Itaya A Kuroda Y 《Organic & biomolecular chemistry》2004,2(19):2852-2860
The nonameric porphyrin assemblies constructed with the series of free base tetraphenylporphyrins Pn having four pyrazine moieties linked with alkyl chains of different lengths, (CH2)n (n = 1, 5, 9, 17, 30), and dimeric [meso-tetrakis(2-carboxy-4-nonylphenyl)porphyrinato]zinc(II), ZnP2, show the effective light-collection effect and the typical Forster-type energy transfer from ZnP2 to Pn. 相似文献
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Shoot tips of cassava (Manihot esculenta Crantz) in vitro plantlets were successfully cryopreserved using the encapsulation-vitrification technique. Nodal cuttings of 5 mm length with one leaf were cultured on modified MS medium in Petri dishes (90 mm x 20 mm) for about 28 days. Excised shoot tips were precultured on sucrose enriched (0.3 M) medium for 16 h, encapsulated and osmoprotected with a mixture of 2 M glycerol and 0.6 M sucrose for 90 min at 25 degree c before dehydration with PVS2 at 0 degree C for 4 h, then plunged in liquid nitrogen. Successfully vitrified shoot tips resumed growth within 3 days, without intermediary callus formation, and developed shoots. Shoot tips sampled from 21 day-old plantlets produced the highest survival of 80 %. The percentage survival of vitrified shoot tips differed from 38 to 80 % depending on the day of excision. The protocol was successfully applied to four cultivars of cassava with about 80 % average percentage of survival. 相似文献
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A new low-coherence interferometric technique is proposed for measuring the group refractive indices of dispersive samples with high accuracy. A tandem configuration of interferometers is used to compensate for the asymmetrical distortion of interferograms that results from the broad spectrum of the light source. The group refractive index can be measured without knowledge of the geometrical thickness of the sample under test. The proposed technique can successfully measure even a thick sample. Computer calculations have shown the effectiveness of the proposed technique, which was verified by preliminary experiments; the difference between the experimental result and the catalog data was 7 x 10(-4). 相似文献