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991.
992.
We focus on thin film microcrystalline germanium (μc-Ge) as narrow gap semiconductor materials for high infrared sensitivity and consider applying it to thermo-photo-voltaic (TPV). The μc-Ge films were prepared on glass substrates by the reactive RF sputtering method with Ar and H2 gas mixtures. We could successfully produce photosensitive μc-Ge films. Higher crystallinity structures do not always result in better carrier properties. Probably, the amorphous portions between crystalline grains have important roles to suppress the grain boundary defects. We applied the μc-Ge to i-layers of pin structure devices, and observed the photovoltaic effect for the first time. 相似文献
993.
Tomohiro Higashi Hiroshi Nishiyama Yohichi Suzuki Yutaka Sasaki Takashi Hisatomi Masao Katayama Tsutomu Minegishi Kazuhiko Seki Taro Yamada Kazunari Domen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(8):2322-2326
Photoelectrochemical water splitting is regarded as a promising approach to the production of hydrogen, and the development of efficient photoelectrodes is one aspect of realizing practical systems. In this work, transparent Ta3N5 photoanodes were fabricated on n‐type GaN/sapphire substrates to promote O2 evolution in tandem with a photocathode, to realize overall water splitting. Following the incorporation of an underlying GaN layer, a photocurrent of 6.3 mA cm?2 was achieved at 1.23 V vs. a reversible hydrogen electrode. The transparency of Ta3N5 to wavelengths longer than 600 nm allowed incoming solar light to be transmitted to a CuInSe2 (CIS), which absorbs up to 1100 nm. A stand‐alone tandem cell with a serially‐connected dual‐CIS unit terminated with a Pt/Ni electrode was thus constructed for H2 evolution. This tandem cell exhibited a solar‐to‐hydrogen energy conversion efficiency greater than 7 % at the initial stage of the reaction. 相似文献
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Masao Yamasaki Yumi Yamasaki Rina Furusho Hayaka Kimura Ichiro Kamei Hiroko Sonoda Masahiro Ikeda Tatsuya Oshima Kenjiro Ogawa Kazuo Nishiyama 《Molecules (Basel, Switzerland)》2021,26(9)
The aim of this study was to evaluate the involvement of nanoparticles prepared from Allium cepa L. as anti-inflammatory agents. In the present study, we identified nanoparticles from Allium cepa L. using the ultracentrifugation exosome purification method. The nanoparticles were referred to as 17,000× g and 200,000× g precipitates, and they contained quercetins, proteins, lipids, and small-sized RNA. The nanoparticles inhibited nitric oxide production from lipopolysaccharide (LPS)-stimulated RAW264 cells without cytotoxic properties. Cellular incorporation was confirmed by laser microscopic observation after PKH26 staining. The inhibition of caveolae-dependent endocytosis and macropinocytosis significantly prevented the incorporation of the nanoparticles but had no effect on the inhibition of nitric oxide in RAW264 cells. Collectively, the identified nanoparticles were capable of inhibiting the LPS response via extracellular mechanisms. Taken together, the way of consuming Allium cepa L. without collapsing the nanoparticles is expected to provide an efficient anti-inflammatory effect. 相似文献
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Optical Review - This paper evaluates the spatial distortion of aerial image and proposes a novel optical design to utilize the distortion as visual expression. Our optical system is based on... 相似文献
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1000.
The one-pot reaction of Me3NBH2CN with Et3O+BF4− followed by addition of BF3·Et2O and water produces a trimethylamine derivative of fluorocyclocarboxyboranylamine, Me3NBH2C(O2BF2NH2) ( 1 ) in 36.0% yield. Compound 1 undergoes exchange reaction between the exo-Me3N moiety and piperidine or pyridine to produce the corresponding piperidine-substituted fluorocyclocarboxyboranylamine ( 2 ) or pyridine-substituted fluorocyclocarboxyboranylamine ( 3 ) in 51.2% or 42.4% yields, respectively. The new compounds were characterized by 1H, 13C, 11B, and 19F nuclear magnetic resonance spectroscopy; Fourier-transform infrared spectroscopy; and elemental analyses and the crystal structure of 1 was determined to confirm its molecular geometry. The in vitro killing effects of 1 , along with its toxicity measurements and molecular docking interactions with matrix metalloproteinases showed a potential promise of such species as both boron neutron capture therapy and boron neutron capture synovectomy agents in the treatment of tumors and rheumatoid arthritis, respectively, in the presence of slow neutrons. 相似文献