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991.
It is rather difficult to design a multilayer photocurrent generator system on the ITO electrode, however, the preparation of thin film with high surface concentration of donor units is indispensable in order to achieve high conversion efficiency. The polymer film of porphyrin bearing pyroles on the electrode was prepared by the potential sweep method. It was indicated that the self-aggregation can be suppressed by encapsulation of the porphyrin unit in the cavity of macro-cyclic host molecule, cyclodextrin. We established the non-equilibrium host-guest system with porphyrins and cyclodextrins for the first time. The photocurrent density and the quantum yield in the porphyrin-cyclodextrin system are remarkably improved. It was demonstrated that the high quantum yield, perhaps 25 times larger, arises from the isolation of the porphyrin unit by cyclodextrin through host-guest interactions. 相似文献
992.
Arimura T Nishioka T Suga Y Kumamoto S Tsuchiya Y Yamaguchi T Tachiya M 《Journal of oleo science》2007,56(3):155-158
Zn(II)porphyrin-substituted calix[4]arene 1 serves as molecular tweezers for 1,4-diazabicyclo[2.2.2] octane (DABCO) selectively, which led to the formation of Ensemble I. The molecular segments composing the calixarene cavity change upon inclusion of DABCO as Ensemble I were evaluated through (13)C NMR longitudinal relaxation times (T(1)) for the first time. As for Ensemble I, the 1:1 complex should be formed. The T(1) values for Ensemble I are generally smaller than those for 1: in CDCl(2)CDCl(2), DT1 = 5.03 s for C-1, 5.31 s for C-2, 0.13 s for C-3, 0.7 s for C-4, and 0.16 s for C-5. This substantiates that the rings of Ensemble I are firmly freezed because of the two-point coordination by DABCO. In 1, the T1 values for C-3 are always greater than those for C-4, and the difference between C-3 and C-4 is slight. As for Ensemble I, on the other hand, the difference between C-3 and C-4 is large. We can suggest two different motions for phenol units in 1 and Ensemble I: a rotational motion around a C-1 to C-4 axis (A) and a seesaw motion around a C-2 to C-2' axis (B). The data indicate that in Ensemble I motion (A) is predominant over motion (B). This indicates that motion (B) is specifically suppressed because of the two-point coordination interactions in Ensemble I. 相似文献
993.
Nagahara Y Nishida Y Isoda M Yamagata Y Nishikawa N Takada K 《Journal of oleo science》2007,56(6):289-295
In recent years, hair coloring gains popularity as a trend of consumer's hair care. This coloring frequently damages hair. In response to this, a new shampoo-base was developed for repairing hair damaged by coloring. The new shampoo-base was prepared by dispersing cationic assembly in a solution of amphoteric surfactants. The mixture of behenyl trimethyl ammonium chloride (C22TAC) and behenyl alcohol (C22OH) was applied as the cationic assembly, which are dispersed in amido propyl betaine laurate (LPB) solution. LPB, which behaves as an amphoteric surfactant, was used as the wash-base. It was verified from the results on the measurements of DSC, calorimeter polarization, cryo-SEM and X-ray diffraction that the cationic assembly has a crystalline structure in the LPB solution. The new shampoo-base was highly efficient to change the color-damaged hair from hydrophilic to hydrophobic. The friction level of the hair washed with the new shampoo-base recovered to the same state as that of healthy hair. The exfoliation of cuticle was reduced after washing with the new shampoo-base. 相似文献
994.
Solid solutions and composite nanoparticles in the TiO2-SnO2 system were directly formed via the hydrothermal treatment of precursor solutions of TiCl4 and SnCl4 under weakly basic conditions in the presence of urea. The rutile-type (Ti, Sn)O2 solid solutions were formed in the composition range of Ti 0-70 mol%. The composite nanoparticles consisting of anatase- and rutile-type phases were formed at the composition of Ti 80 and Ti 90 mol%. The change in the lattice parameters a0 and c0 of the rutile-type solid solutions followed the Vegard Law. The crystallite size of the rutile-type solid solutions was in the range of 5-10 nm. The diffuse reflectance spectra varied with changing Ti content in the precipitates. The photocatalytic activity of composite nanoparticles synthesized at 240 °C was higher than that synthesized at 180 °C. The composite nanoparticles consisting of anatase- and rutile-type phases with compositions Ti0.90Sn0.10O2 and Ti0.80Sn0.20O2 showed improved photocatalytic activity. 相似文献
995.
Matsuda S Hara M Miura M Matsuda T Ueda M Satoh Y Hashimoto KY 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2011,58(8):1684-1687
We investigated the correlation between the temperature coefficient of elasticity (TCE) and Fourier transform infrared (FT-IR) absorption spectra of SiO(2) for SAW devices. The measurement indicated that the TCE is strongly correlated with peak frequencies; that is, with the fractional change of the Si-O-Si bond angle with temperature. 相似文献
996.
Kazuyoshi Sakai Genzoh Isomura Masanori Shinzato Hideki Imada Keiki Yamada 《Microscopy research and technique》2011,74(9):819-824
We investigated the distribution of T lymphocytes, B lymphocytes, and S‐100 protein‐immunoreactive dendritic‐like in the anal tonsil of the laboratory shrew, Suncus murinus. In adult animals, T lymphocytes were located mainly at the periphery of the anal tonsil, especially around small blood vessels. B lymphocytes were located in the central and subepithelial region of the anal tonsil, which includes primary lymphoid follicles, and in which there are small numbers of scattered T lymphocytes. B and T lymphocytes were distributed over 72.7 and 27.3% of the tonsillar area, respectively. However, their areas of distribution were not clearly distinguished. The areas containing B lymphocytes were enriched in S‐100 protein antibody‐immunoreactive cells, which exhibited a dendritic shape. These S‐100‐positive cells appeared to be identical to the follicular dendritic cells (FDC) seen in the follicles of lymphoid organs. These results suggest that the anal tonsils constitute one of the gut‐associated lymphoid tissues (GALT), and that a function of the anal tonsil includes the capture of intruding antigens that would generate protective antibody responses. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc. 相似文献
997.
998.
Fukuda H Ueda T Ohnaka T Sato N Shinto M Tanaka T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2011,52(2):117-120
Thiabendazole (TBZ), a pesticide with antifungal activity, was detected in toasted and seasoned laver which had been reported as tasting unpleasant by consumers in March 2008. From a survey of the manufacturing process, it was concluded that the TBZ contamination had originated from a sponge-roller which was used to paste seasoned liquid onto the toasted laver. At that time it was found that TBZ is widely used to prevent fungal contamination of sponge-rollers. For further survey of TBZ contamination in the laver, we developed a more sensitive detection method using LC-MS/MS. With our new method, six commercial products harvested in March 2008 and July 2009, respectively, were tested. Five out of six samples harvested in 2008 were positive for TBZ, with values in the range from 0.014 to 1.736 μg/g. Only one sample harvested in 2009 contained a detectable level of TBZ. The data obtained here contributed to the improvement of the manufacturing process. 相似文献
999.
Watanabe M Ichinose K Sasano K Ozaki Y Tsuiki T Hidaka H Kanemoto S 《Journal of Bioscience and Bioengineering》2011,111(1):67-70
An efficient and rapid adventitious shoot regeneration system from young cotyledons of Jatropha curcas L. was developed. After testing several combinations of plant growth regulators, the highest regeneration frequency was obtained for the medium supplemented with 3 mg/l BA and 0.1 mg/l IBA. This system will be useful for promoting genetic improvement efforts in J. curcas. 相似文献
1000.
Yuya Kasho Hidetoshi Hirai Masanori Tsukuda Ichiro Omura 《Microelectronics Reliability》2011,51(9-11):1689-1692
“Stealth” electric current probing technique for power electronics circuits, power device modules and chips makes it possible to measure electric current without any change or disassembling the circuit and the chip connection for the measurement. The technique consists of a tiny-scale magnetic-field coil, a high speed analog amplifier and a digitizer with numerical data processing. This technique can be applied to a single bonding wire current measurement inside IGBT modules, chip scale current redistribution measurement and current measurement for surface mount devices. The “stealth” current measurement can be utilized in the failure mechanism understanding of power devices including IGBT short circuit destruction. 相似文献