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51.
D‐A1‐D‐A2 Backbone Strategy for Benzobisthiadiazole Based n‐Channel Organic Transistors: Clarifying the Selenium‐Substitution Effect on the Molecular Packing and Charge Transport Properties in Electron‐Deficient Polymers 下载免费PDF全文
Yang Wang Tsukasa Hasegawa Hidetoshi Matsumoto Takehiko Mori Tsuyoshi Michinobu 《Advanced functional materials》2017,27(33)
Unipolar n‐type semiconducting polymers based on the benzobisthiadiazole (BBT) unit and its heteroatom‐substituted derivatives are for the first time synthesized by the D‐A1‐D‐A2 polymer‐backbone design strategy. Selenium (Se) substitution is a very effective molecular design, but it has been seldom studied in n‐type polymers. In this study, within the similar conjugated framework, the Se substitution effects on the optical, electrochemical, solid‐state polymer packing, electron mobility, and air‐stability of the target unipolar n‐type polymers are unraveled. Replacing the sulfur (S) atom in the thiadiazole heterocycles with the Se atom leads to narrower bandgaps and deeper lowest unoccupied molecular orbital (LUMO) levels of the n‐type polymers. Furthermore, the Se‐substituted polymer (pSeN‐NDI) shows shorter lamellar packing distances and stronger edge‐on π–π stacking interactions than its S‐counterpart (pSN‐NDI), as observed by the two‐dimensional grazing‐incidence wide‐angle X‐ray scattering (GIWAXS) patterns. With the deeper LUMO level and thin‐film microstructures suitable for transistors, pSeN‐NDI exhibits four‐fold higher electron mobilities (μe) than pSN‐NDI. However, the other Se‐containing polymer, pSeS‐NDI, forms rather amorphous film structures, which is caused by its limited thermal stability and decomposition during the thermal annealing processes, thus giving rise to a lower μe than its S‐counterpart (pBBT‐NDI). Most importantly, pBBT‐NDI demonstrates an electron mobility of 0.039 cm2 V?1 s?1, which is noticeable among the unipolar n‐type polymers based on the BBT and its analogs. 相似文献
52.
Wireless Sensor Network (WSN) is used in Emergency Management System (EMS). If emergency situation happens, real-timely transmitting emergency information in dynamically changing environment should be assured. But this requirement could not be satisfied by conventional approaches which are based on static situation and centralized management. In this paper, to satisfy this requirement, autonomous community construction technology is proposed for single emergency. Emergency information could be transmitted in community and protected from interference of other information’s transmission. Moreover, autonomous coordination technology is proposed for multiple emergencies’ information’s transmission. Via this technology, each emergency could have its individual route to transmit emergency information. Each emergency information’s transmission will not influence with each other. Evaluation results are provided to demonstrate the improvement. 相似文献
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Ramez Alhazzaa Andrew R. Bridle Trevor A. Mori Anne E. Barden Peter D. Nichols Chris G. Carter 《Food chemistry》2013
Pathogen infection stimulates the fatty acid (FA) metabolism and the production of pro-inflammatory derivatives of FA. Barramundi, Lates calcarifer, was fed on a diet rich in preformed long-chain (?C20) polyunsaturated fatty acids (LC-PUFA) from fish oil (FO), to compare with diets containing high levels of C18 precursors for LC-PUFA – stearidonic (SDA) and γ-linolenic acid (GLA) – from Echium plantagineum (EO), or rapeseed oil (RO) rich in α-linolenic acid (ALA), but a poor source of LC-PUFA and their precursors. After 6 weeks, when growth rates were similar amongst the dietary treatments, a sub-lethal dose of Streptococcus iniae was administered to half of the fish, while the other half were maintained unchallenged and were pair-fed with the infected fish. Under a disease challenge situation, the tissue FA depots depleted at 3 days post-infection (DPI) and were then restored to their previous concentrations at 7 DPI. During the infection period, EO fish had a higher content of n3 and n6 PUFA in their tissues, higher n3:n6 PUFA ratio and reduced levels of the eicosanoids, TXB2 and 6-keto-PGF1α, in their plasma compared with RO fish. Fish fed on FO and EO had a longer lasting and enduring response in their FA and eicosanoid concentrations, following a week of bacterial infection, compared with those fed on RO. EO, containing SDA and GLA and with a comparatively higher n3:n6 PUFA ratio, proved more effective than RO in compensating for immunity stress. 相似文献
55.
Toyama T Murashita M Kobayashi K Kikuchi S Sei K Tanaka Y Ike M Mori K 《Environmental science & technology》2011,45(15):6524-6530
We investigated biodegradation of technical nonylphenol (tNP) in Phragmites australis rhizosphere sediment by conducting degradation experiments using sediments spiked with tNP. Accelerated tNP removal was observed in P. australis rhizosphere sediment, whereas tNP persisted in unvegetated sediment without plants and in autoclaved sediment with sterile plants, suggesting that the accelerated tNP removal resulted largely from tNP biodegradation by rhizosphere bacteria. Three bacterial strains, Stenotrophomonas sp. strain IT-1 and Sphingobium spp. strains IT-4 and IT-5, isolated from the rhizosphere were capable of utilizing tNP and 4-tert-octylphenol as a sole carbon source via type II ipso-substitution. Oxygen from P. australis roots, by creating highly oxygenated conditions in the sediment, stimulated cell growth and the tNP-degrading activity of the three strains. Moreover, organic compounds from P. australis roots functioned as carbon and energy sources for two strains, IT-4 and IT-5, supporting cell growth and tNP-degrading activity. Thus, P. australis roots elevated the cell growth and tNP-degrading activity of the three bacterial strains, leading to accelerated tNP removal. These results demonstrate that rhizoremediation of tNP-contaminated sediments using P. australis can be an effective strategy. 相似文献
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Kashii M Fujisawa R Adachi H Mori Y Sasaki T Koga Y Takano K Kanaya S Matsumura H Inoue T Murakami S Sugamoto K Yoshikawa H 《Journal of Bioscience and Bioengineering》2006,102(4):372-374
We developed a novel technique for detaching protein crystals from glass capillary tube using the counter diffusion crystallization technique by femtosecond laser irradiation. X-ray diffraction analysis demonstrated that femtosecond laser irradiation has little effect on crystallinity. This technique will contribute to progress in structural genomics as a powerful tool. 相似文献
59.
Jonathan M Hodgson Julie M Proudfoot Kevin D Croft Ian B Puddey Trevor A Mori Lawrence J Beilin 《Journal of the science of food and agriculture》1999,79(4):561-566
Lipoprotein oxidation is a process thought to be involved in atherogenesis. Dietary antioxidants that prevent or inhibit oxidative damage to lipoproteins may help to prevent atherosclerosis. Both black and green teas can be major dietary sources of flavonoids and other phenolics with antioxidant activity. Results of previous studies suggest that green tea may have a greater antioxidant potential than black tea. The aim of this study was to assess and compare the effects of black and green tea on in vitro lipoprotein oxidation. The tea extracts were prepared using a method similar to that used to prepare infusions of tea for drinking. Antioxidant activities of seven black teas and four green teas were assessed using an in vitro assay that measures Cu2+ ‐induced oxidation of lipoproteins in human serum. All tea extracts inhibited in vitro lipoprotein oxidation in human serum to a similar extent. No significant difference in antioxidant activity was found between black and green tea. Caffeine prepared to a comparable concentration to that found in tea had no effect on lipoprotein oxidation. Further studies are required to determine the importance of these findings in relation to possible protective effects of black and green tea consumption against atherogenesis and cardiovascular disease. © 1999 Society of Chemical Industry 相似文献
60.
Observation of the epicerebral microcirculation studied by fluorescein angiography (author's transl)
Fluorescein angiography was carried out by modification of method as described by Feindel et al. The hemisphere was widely exposed to allow visualization of surface blood vessels. In the experimental room, the dye was injected rapidly either through a fine polyethylen catheter placed in the lingual artery or thorough the cannula in the femoral vein. For "lingual" angiography 1.6 ml of 1% sodium fluorescein were used, while for "femoral" angiography, 4 ml of 10% solution were injected. In the operating room 4 ml of 1% sodium fluorescein are rapidly injected into an internal carotid catheter. Serial photographs of the passage of the dye through the surface vessels of the hemisphere were taken with a motor-drive Nikon camera at interval of 0.4 seconds, or longer when indicated, starting at the time of the injection. The shutter was synchronized with the discharge of a rapid re-charging stroboscopic light. A wratten gelatin filter 47A (Kodak) was used over the light and a Nikon filter Y52 over the camera lens for Kodak high speed ektachrome film to obtain color photographs. The timing of the interval between photographs was measured to within in 0.4 seconds by recording from a ink written oscillography synchronized with the shutter. Thus the velocity of flow in individual vessels could be calculated from the serial photographs. 相似文献