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981.
982.
Satoshi Tohoda Daisuke Fujishima Ayumu Yano Akiyoshi Ogane Kenta Matsuyama Yuya Nakamura Nozomu Tokuoka Hiroshi Kanno Toshihiro Kinoshita Hitoshi Sakata Mikio Taguchi Eiji Maruyama 《Journal of Non》2012,358(17):2219-2222
To reduce the power generation cost of heterojunction with intrinsic thin layer (HIT) solar cells, it is necessary to use a thinner crystalline silicon wafer, as well as to improve the conversion efficiency. We have experimentally confirmed that VOC of the HIT solar cell increases with decreasing the wafer thickness, and can reach a very high VOC of 747 mV with a 58-μm-thick wafer owing to a sufficiently low surface recombination velocity. We also indicate the future directions for improving the efficiency. The uniformization of the texture size of the silicon surface and reduction of the carrier density in TCO film while maintaining an equal or lower conductivity are effective for improving the optical confinement. 相似文献
983.
Kouhei Tsushima Hitoshi Nakata Kunitaka Monji Hidenori Deki Kazuro Murayama 《Journal of Non》2012,358(17):2090-2095
The stretched exponential luminescence decay observed at temperatures lower than 20 K transits to the power law decay due to the electron-hopping at localized band tail states near 60 K in the hydrogenated amorphous silicon (a-Si:H). The luminescence decay at 4.2 K in a-Si:H is quite similar to that of Si-nanoparticles in the porous Si (p-Si). It is explained from the comparison with p-Si that the slow luminescence of the life time of ~ 1 ms is due to the recombination of excitonic electron–hole pairs at the spin triplet state quantum-confined in the hydrogen-free Si nanostructure in a-Si:H. The fast luminescence of the life time of ~ 1 μs is due to the recombination of the pairs at the spin-singlet state and the life time is explained as due to the indirect optical transition. 相似文献
984.
985.
Sasaki T Nakao K Tomishige K Kunimori K 《Chemical communications (Cambridge, England)》2006,(36):3821-3823
Energetic activation of a methane molecular-beam promoted remarkably the direct catalytic partial oxidation on Pt and Rh foils, in particular, hydrogen formation was dramatically enhanced. 相似文献
986.
Kodamatani H Shimizu H Saito K Yamazaki S Tanaka Y 《Journal of chromatography. A》2006,1102(1-2):200-205
A novel high-performance liquid chromatographic method for the determination of aromatic compounds based on the on-line photochemical degradation and subsequent tris(2,2'-bipyridine)ruthenium(III) chemiluminescence detection has been developed. Chemiluminescence intensity depended upon the number of aromatic rings, UV irradiation time, and variety of substituted functional groups. One of the decomposition products of aromatic compounds by UV irradiation was identified as oxalic acid. As one application of this methodology, determination of catechins in tea has been shown. Calibration graphs, based on standard (-)-epicatechin and (-)-epigallocatechin gallate solutions, were linear over the range of 0.1-50 microM. The detection limits (signal-to-noise ratio=3) were 0.8 pmol for (-)-epigallocatechin gallate and 1.2 pmol for (-)-epicatechin. The high-performance liquid chromatography-chemiluminescence (HPLC-CL) detection method with a post-column photochemical reactor can be applied to the sensitive and selective determination of catechins in tea. 相似文献
987.
Takaishi S Kawakami D Yamashita M Sasaki M Kajiwara T Miyasaka H Sugiura K Wakabayashi Y Sawa H Matsuzaki H Kishida H Okamoto H Watanabe H Tanaka H Marumoto K Ito H Kuroda S 《Journal of the American Chemical Society》2006,128(19):6420-6425
We synthesized a novel iodo-bridged linear chain platinum compound, having the quasi-two-dimensional charge-density-wave (CDW) ground state and the smallest band gap. In this compound, we discovered an anomalous valence state in the boundary region at which the CDW phase alternates in the crystal by means of ESR, X-ray diffuse scattering, STM, and electrical resistivity. This anomalous state can be explained by the fast fluctuation between Pt(IV)-I...Pt(II) and Pt(II)...I-Pt(IV) in the double well potential. This is the first observation of the dynamical fluctuation of the CDW phase among the quasi one-dimensional halogen-bridged complexes. 相似文献
988.
989.
Matsuhira T Yamamoto H Onoda A Okamura TA Ueyama N 《Organic & biomolecular chemistry》2006,4(7):1338-1342
In this study, we synthesized two novel carboxylic acid and carboxylate compounds, both of which had an amide group linked with an azomethine moiety to introduce photoinduced switching of the intramolecular NH...O hydrogen bond. We suggest that the cis-carboxylate compound forms a stronger intramolecular NH...O hydrogen bond than the cis-carboxylic acid compound. 相似文献
990.