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排序方式: 共有739条查询结果,搜索用时 9 毫秒
731.
732.
Shinnosuke Mori Hiroshi Fukui Masanori Oishi Masayuki Sakuma Mari Kawakami Junko Tsukioka Katsumi Goto Nobuhiro Hirai 《Journal of chemical ecology》2018,44(6):591-600
Flowering plants attract pollinators via various stimuli such as odor, color, and shape. Factors determining the foraging behavior of pollinators remain a major theme in ecological and evolutionary research, although the floral traits and cognitive ability of pollinators have been investigated for centuries. Here we show that the autofluorescence emitted from pollen and anthers under UV irradiation may act as another attractant for flower-visiting insects. We have identified fluorescent compounds from pollen and anthers of five plant species as hydroxycinnamoyl derivatives. The fluorescent compounds are also shown to quench UV energy and exhibit antioxidant activity, indicating a function as protectants of pollen genes from UV-induced damage. A two-choice assay using honeybees in the field demonstrated that they perceived the blue fluorescence emitted from the fluorescent compounds and were attracted to it. This result suggested that the fluorescence from pollen and anthers serves as a visual cue to attract pollinators under sunlight. 相似文献
733.
Wilman Septina Shigeru Ikeda M. Alam Khan Takeshi Hirai Takashi Harada Michio Matsumura Laurence M. Peter 《Electrochimica acta》2011,(13):4882
Potentiostatic deposition of Cu2O thin films on glass substrates coated with F-doped SnO2 from an alkaline electrolyte solution (pH 12.5) containing copper (II) sulfate and lactic acid was studied for fabrication of a Cu2O/Al-doped ZnO (AZO) heterojunction solar cell. The band gap of the electrodeposited Cu2O films was determined by photoelectrochemical measurements to be around 1.9 eV irrespective of the applied potentials. The solar cells with a glass/FTO/Cu2O/AZO structure were fabricated by sputtering an AZO film onto the Cu2O film followed by deposition of an Al contact by vacuum evaporation. The highest efficiency of 0.603% was obtained with a Cu2O film deposited at −0.6 V (vs. Ag/AgCl). This was attributed to better compactness and purity of the Cu2O film than those of the Cu2O films deposited at other potentials. 相似文献
734.
M. Arakawa S. Tobishima T. Hirai J. Yamaki 《Journal of Applied Electrochemistry》1999,29(10):1191-1196
The effects of the purification of LiAsF6–2-methyl tetrahydrofuran (2MeTHF)/ethylene carbonate (EC) mixed solvent organic electrolytes on the charge–discharge cyclability of lithium metal anodes has been investigated by using an accelerated method for evaluating lithium cycling efficiency. This method involves cycle tests on coin cells with an amorphous V2O5–P2O5 (95:5 molar ratio) cathode and an anode containing a small amount of lithium. Using this method, the cycle life of the cell was determined over a short period simply from the lithium cycling efficiency. The lithium cycling efficiency in LiAsF6–2MeTHF/EC was improved by removing both water and organic impurities such as peroxides. An electrolyte containing less than 14ppm of water and 20ppm of organic impurities had a high lithium cycling efficiency of 97.2%. 相似文献
735.
Tomoki Osumi Musashi Seike Keigo Oyama Shinya Higashimoto Tomoyasu Hirai Yoshinobu Nakamura Syuji Fujii 《应用聚合物科学杂志》2021,138(37):51009
Polypyrrole grains are synthesized by aqueous chemical oxidative polymerization using ferric chloride as an oxidant in the presence of bis(2-ethylhexyl) sulfosuccinate sodium salt as both a dopant and a hydrophobizing agent. The resulting grain products are characterized in terms of their size, morphology, surface and bulk chemical compositions, hydrophilicity-hydrophobicity balance, (photo) thermal property, and electrical conductivity. Scanning electron microscopy studies indicate that the grains are aggregates of atypical primary grains with submicrometer size. Elemental microanalysis and thermogravimetric analysis confirm that the polypyrrole is preferably doped with dioctyl sulfosuccinate compared with chloride ion, and dioctyl sulfosuccinate/chloride ion dopant ratio increases with an increase of bis(2-ethylhexyl) sulfosuccinate sodium salt concentration in the polymerization systems. The grains show near-infrared light-to-heat photothermal property, which is confirmed by thermography. The data obtained through X-ray photoelectron spectroscopy indicate the presence of dioctyl sulfosuccinate dopants on the surface of the grains, and therefore the dried polypyrrole grains show hydrophobic character. The dried grains can work as a light-responsive liquid marble (LM) stabilizer. Motions of the LM can be driven by near-infrared laser irradiation-induced Marangoni flow on planar air-water surface. The release of internal liquid can be achieved by controlled disruption of the LM via external stimulus application. 相似文献
736.
737.
Eri Adams Takae Miyazaki Ju Yeon Moon Yuji Sawada Muneo Sato Kiminori Toyooka Masami Yokota Hirai Ryoung Shin 《International journal of molecular sciences》2020,21(23)
Syringic acid, a phenolic compound, serves a variety of beneficial functions in cells. Syringic acid increases in plants in response to cesium, and exogenous application of syringic acid resulted in a significant attenuation of cesium-induced growth defects in Arabidopsis. In addition, cesium or syringic acid application to plants also resulted in increased lignin deposition in interfascicular fibers. To better understand the role of lignin and syringic acid in attenuating cesium-induced growth defects, two mutants for Arabidopsis REDUCED EPIDERMAL FLUORESCENE 4 (REF4) and fourteen laccase mutants, some of which have lower levels of lignin, were evaluated for their response to cesium. These mutants responded differently to cesium stress, compared to control plants, and the application of syringic acid alleviated cesium-induced growth defects in the laccase mutants but not in the ref4 mutants. These findings imply that lignin plays a role in cesium signaling but the attenuation of cesium stress defects by syringic acid is mediated by regulatory components of lignin biosynthesis and not lignin biosynthesis itself. In contrast, syringic acid did not alleviate any low potassium-induced growth defects. Collectively, our findings provide the first established link between lignin and cesium stress via syringic acid in plants. 相似文献
738.
Hidenori Takagi Liang Dong Morgan D. Kuczler Kara Lombardo Mitsuharu Hirai Sarah R. Amend Kenneth J. Pienta 《International journal of molecular sciences》2020,21(23)
Circulating tumor cells (CTCs) are a promising biomarker for cancer liquid biopsy. To evaluate the CTC capture bias and detection capability of the slit filter-based CTC isolation platform (CTC-FIND), we prospectively compared it head to head to a selection-free platform (AccuCyte®-CyteFinder® system). We used the two methods to determine the CTC counts, CTC positive rates, CTC size distributions, and CTC phenotypes in 36 patients with metastatic cancer. Between the two methods, the median CTC counts were not significantly different and the total counts were correlated (r = 0.63, p < 0.0001). The CTC positive rate by CTC-FIND was significantly higher than that by AccuCyte®-CyteFinder® system (91.7% vs. 66.7%, p < 0.05). The median diameter of CTCs collected by CTC-FIND was significantly larger (13.0 μm, range 5.2–52.0 vs. 10.4 μm, range 5.2–44.2, p < 0.0001). The distributions of CTC phenotypes (CK+EpCAM+, CK+EpCAM− or CK−EpCAM+) detected by both methods were similar. These results suggested that CTC-FIND can detect more CTC-positive cases but with a bias toward large size of CTCs. 相似文献
739.
Water management in polymer electrolyte membrane fuel cells (PEMFCs) is extremely important for the high performance and durable operation of fuel cells. Therefore, fundamental understanding of water transport involved in operating PEMFCs is necessary. This article presents a review of in situ magnetic resonance imaging (MRI) visualisation of water in operating PEMFCs, which is recognised as a powerful diagnostic tool for probing water behaviours, both in flow fields and in the membrane electrode assembly (MEA). The basic principles and hardware related to MRI visualisation are described with emphasis on the design, construction and material selection of a PEMFC for MRI experiments. The MRI results reported by several groups are outlined to illustrate the versatility and potential usefulness of in situ visualisation of water in operating PEMFCs using MRI. 相似文献