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排序方式: 共有494条查询结果,搜索用时 0 毫秒
491.
The influence of alkylaminopyridine additives 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 with an I−/I3− redox electrolyte in acetonitrile was studied. The current–voltage characteristics were measured for more than 20 different alkylaminopyridines under AM 1.5 (100 mW/cm2). The alkylaminopyridine additives tested had varying effects on the performance of the cell. All the additives decreased the short circuit photocurrent density (Jsc), but increased the open-circuit photovoltage (Voc) of the solar cell. Molecular orbital calculations imply that the dipole moment of the alkylaminopyridine molecules influences the Jsc of the cell and that the size, solvent accessible surface area, and ionization energy all affect the Voc of the cell. The highest Voc of 0.88 V was observed in an electrolyte containing 4-pyrrolidinopyridine, which is comparable to the maximum Voc of 0.9 V for a cell consisting of TiO2 electrode and I−/I3− redox system. 相似文献
492.
Kohjiro Hara Yasuhiro Tachibana Yasuyo Ohga Akira Shinpo Sadaharu Suga Kazuhiro Sayama Hideki Sugihara Hironori Arakawa 《Solar Energy Materials & Solar Cells》2003,77(1):89-103
We have developed dye-sensitized nanocrystalline TiO2 solar cells (DSSCs) based on novel coumarin-dye photosensitizers. The absorption spectra of these novel dyes are red-shifted remarkably in the visible region relative to the spectrum of C343, a conventional coumarin dye. Introduction of a methine unit (–CH=CH–) connecting the cyano (–CN) and carboxyl (–COOH) groups into the coumarin framework expanded the π-conjugation in the dye and thus resulted in a wide absorption in the visible region. These novel dyes performed as efficient photosensitizers for DSSCs. A DSSC based on 2-cyano-5-(1,1,6,6-tetramethyl-10-oxo-2,3,5,6-tetrahydro-1H,4H,10H-11-oxa-3a-aza-benzo[de]anthracen-9-yl)-penta-2,4-dienoic acid (NKX-2311), produced a 6.0% solar energy-to-electricity conversion efficiency (η), the highest performance among DSSCs based on organic-dye photosensitizers, under AM 1.5 irradiation (100 mW cm–2) with a short-circuit current density (Jsc) of 14.0 mA cm–2, an open-circuit voltage (Voc) of 0.60 V, and a fill factor of 0.71. Our results suggests that the structure of NKX-2311 whose carboxyl group is directly connected to the –CH=CH– unit, is advantageous for effective electron injection from the dye into the conduction band of TiO2. In addition, the cyano group, owing to its strong electron-withdrawing ability, might play an important role in electron injection in addition to a red shift in the absorption region. On a long-term stability test under continuous irradiation with white light (80 mW cm–2), stable performance was attained with a solar cell based on the NKX-2311 dye with a turnover number of 2.6×107 per one molecule. 相似文献
493.
Tuneo Suzuki Hirofusa Shirai Nobumasa Hojo 《Journal of Inorganic and Organometallic Polymers》1994,4(3):251-260
The kinetics of the metal exchange reaction between Cu(II)-poly(vinyl alcohol) [Cu(II)-PVA] and Zn(II)-ethylenediamine-N,N,N,N-tetraacetic acid [Zn(II)-EDTA] has been studied by mixing both solutions in a spectrophotometer at pH 10.0 to 11.0, ionic strength =0.10(KNO3), and 15 to 35°C. The reaction is initiated by the formation of unstable Cu(II)-H-PVA through attack of H+ ion on the Cu(II)-PVA complex, and both reactions, ligand exchange and metal exchange, proceed simultaneously. The metal exchange step may be rate determining. The rate equation and rate constants of this reaction were determined as follows: –d[Cu(II)-PVA]/dt=k
0(H)[PVA–][Cu(II)-PVA] [Zn(II)-EDTA], wherek
0(H)=k
1+(k2+k3)[H+],k
1=5.98±1.64M
–1 s–1, andk
2+k
3=k2
K
Cu(II)-H-PVA
–H
+k3
K
Zn(II)-EDTA
H
=(5.91±0.89)×107
M
–2 s–1. 相似文献
494.
Tohru Ohmori Toshimitsu Yamaoka Koichi Ando Sojiro Kusumoto Yasunari Kishino Ryou Manabe Hironori Sagara 《International journal of molecular sciences》2021,22(2)
The tyrosine kinase activity of epidermal growth factor receptors (EGFRs) plays critical roles in cell proliferation, regeneration, tumorigenesis, and anticancer resistance. Non-small-cell lung cancer patients who responded to EGFR-tyrosine kinase inhibitors (EGFR-TKIs) and obtained survival benefits had somatic EGFR mutations. EGFR-TKI-related adverse events (AEs) are usually tolerable and manageable, although serious AEs, including lung injury (specifically, interstitial lung disease (ILD), causing 58% of EGFR-TKI treatment-related deaths), occur infrequently. The etiopathogenesis of EGFR-TKI-induced ILD remains unknown. Risk factors, such as tobacco exposure, pre-existing lung fibrosis, chronic obstructive pulmonary disease, and poor performance status, indicate that lung inflammatory circumstances may worsen with EGFR-TKI treatment because of impaired epithelial healing of lung injuries. There is limited evidence from preclinical and clinical studies of the mechanisms underlying EGFR-TKI-induced ILD in the available literature. Herein, we evaluated the relationship between EGFR-TKIs and AEs, especially ILD. Recent reports on mechanisms inducing lung injury or resistance in cytokine-rich circumstances were reviewed. We discussed the relevance of cytotoxic agents or immunotherapeutic agents in combination with EGFR-TKIs as a potential mechanism of EGFR-TKI-related lung injury and reviewed recent developments in diagnostics and therapeutics that facilitate recovery from lung injury or overcoming resistance to anti-EGFR treatment. 相似文献