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Hitoshi Kusama Yoshinari Konishi Hideki Sugihara Hironori Arakawa 《Solar Energy Materials & Solar Cells》2003,80(2):2533
The influence of alkylpyridines additive to an I−/I3− redox electrolyte in acetonitrile on the performance of a bis(tetrabutylammonium)cis-bis(thiocyanato)bis(2,2′-bipyridine-4-carboxylic acid, 4′-carboxylate)ruthenium(II) dye-sensitized TiO2 solar cell was studied. I–V measurements were performed using more than 30 different alkylpyridines. The alkylpyridine additives showed a significant influence on the performance of the cell. All the additives decreased the short-circuit photocurrent (Jsc), but most of the alkylpyridines increased the open-circuit photovoltage (Voc) and fill factor (ff) of the solar cell. The results of the molecular orbital calculations suggest that the dipole moment of the alkylpyridine molecules correlate with the Jsc of the cell. These results also suggest that both the size and ionization energy of pyridines correlate with the Voc of the cell. Under AM 1.5 (100 mW/cm2), the highest solar energy conversion efficiency (η) of 7.6% was achieved by using 2-propylpyridine as an additive, which was more effective than the previously reported additive, 4-t-butylpyridine. 相似文献
33.
Data mining assisted by theoretical calculations for improving dye-sensitized solar cell performance
Hitoshi Kusama Yoshinari Konishi Hideki Sugihara 《Solar Energy Materials & Solar Cells》2007,91(1):76-78
Data mining using experimental data and information generated from theoretical calculations is proposed to study dye-sensitized solar cells, which are complex systems. This method led to new knowledge about the influence of imidazole derivatives as additives in an electrolytic solution on the cell performance. It was found that the solar energy conversion efficiency is strongly correlated to the Mulliken charge of the carbon atom at position 4 in the imidazole group. This result indicates that data mining assisted by theoretical calculations should facilitate the rate that cell performance is improved. 相似文献
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Three patients developed acute colitis, either de novo, or as an exacerbation of pre-existing colitis, following the use of oral acyclovir, prescribed for Herpes zoster or Herpes simplex infection. Rechallenge with oral acyclovir was performed in one patient, and resulted in a recurrence of colitic symptoms. It is speculated that acyclovir can have a direct irritant effect on large bowel mucosa. 相似文献
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Sugihara S. Bak T. Nowotny J. Radecka M. Sorrell C. C. 《Journal of Materials Synthesis and Processing》1998,6(5):335-338
This paper reports the results of work function (WF) changes of undoped PbZrO3 during subsequent isothermal oxidation and reduction experiments at 500°C in the p(O2) range between 10 and 2.1 × 104 Pa. The results, obtained during three consecutive runs, indicate that heating at 500°C leads to continuous changes of surface properties resulting in a complex WF vs. time characteristic. The WF changes during the first oxidation are determined by a p(O2)-induced structural transition. The second oxidation results in two competitive processes, such as rapid increase of oxygen non-stoichiometry followed by a structural transition. Finally, the third oxidation is determined by changes of oxygen nonstoichiometry. 相似文献
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Anion exchange membranes containing amino groups, insoluble in acidic and alkaline aqueous solutions, were prepared from chitosan, poly(vinyl alcohol), and glutaraldehyde. Using the membrane in a diaphragm cell, one side being adjusted to be acidic and the other alkaline, it was possible to transport actively halogen ions through the membrane from the acidic side to the alkaline side against the concentration gradient between both sides of the membrane. The active transport of halogen ions through the membrane was significantly influenced by the pH difference and electric potential difference between both sides of the membrane. 相似文献
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The permeation characteristics for polymer aqueous solution and asymmetric structure of cellulose nitrate membranes, in particular the finger-like cavity in the back sponge layer of these membranes, were investigated by changing the preparation conditions of the membranes— the casting solvent, evaporation period, and gelation medium. The formation of the finger-like cavity was dependent on absorption of a water molecule into the casting mixture from the atmosphere during the solvent evaporation process and the exchange velocity between the casting solvent and the gelation medium. The mechanism and conditions for the formation of a finger-like cavity in cellulose nitrate membranes were discussed. 相似文献