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61.
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
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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
62.
Bioinspired Microenvironments: Rational Design of High‐Mobility Semicrystalline Conjugated Polymers with Tunable Charge Polarity: Beyond Benzobisthiadiazole‐Based Polymers (Adv. Funct. Mater. 2/2017)
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63.
Fumito Kitatani Hideo Harada Shinji Goko Nobuyuki Iwamoto Hiroaki Utsunomiya Hidetoshi Akimune 《Journal of Nuclear Science and Technology》2016,53(4):475-485
The 77Se (γ, n) cross section was measured for the energy range from 7.6 to 13.8 MeV by using quasi-monochromatic laser-Compton scattering γ-rays. The advanced method to deduce γ-ray strength functions from (γ, n) cross section was developed. By utilizing the method, the γ-ray strength functions of 77, 78, 80Se were deduced so as to reproduce the 77, 78, 80Se (γ, n) cross sections measured in this work and previous systematic measurements. The inverse (n, γ) cross sections for 76, 77, 79Se isotopes were calculated using the statistical model calculation code CCONE with the deduced γ-ray strength functions. The uncertainty of the calculated 79Se(n, γ)80Se cross section was evaluated by comparing the calculations and the experimental data on 76, 77Se (n, γ) cross sections. 相似文献
64.
Confocal Raman spectroscopy was applied to the characterization of various states emerging in the screening of protein crystallization. Four main characterized states, namely single crystals, microcrystals, precipitates, and clear drops without solid materials, appear in a droplet for crystallization; the first three states should be critically distinguished and characterized because of the limitations of visual observation under an optical microscope. Using lysozyme and other proteins, crystallization was performed by the hanging drop vapor diffusion technique and was monitored through an automated confocal Raman system. Prior to the spectroscopic analysis, an optical microscope with a charge-coupled device (CCD) camera and associated image processing software were used to rapidly identify the XY locations to be measured spectroscopically by focusing the laser beam on a test sample. Instead of the current image analysis by optical microscopy, confocal Raman spectroscopy with a high spatial resolution was used to identify the state of protein crystallization. Such real-time Raman monitoring also distinguished real protein crystals from pseudo-protein crystals emerging in a crystallization droplet. 相似文献
65.
Susumu Shima Hidetoshi Kotera Kei Kamitani Toshimitsu Bando 《Metals and Materials International》1998,4(3):404-407
This paper deals with development of an incremental deep drawing process. On a newly developed incremental deep drawing set-up, the aluminium sheets are formed; the forming is carried out by deep-drawing the blank as in the conventional method but incrementally. Fractures at the punch or die corner in the blank may or may not occur depending on the conditions; the process parameters involved are punch size, punch corner radius, increment in punch displacement, blank holding force or pressure, etc. It is thus shown that different shapes are formed by one set of common tools. It is thereby confirmed that incremental deep drawing is possible without using a particular tool set for a particular shape. 相似文献
66.
INTRODUCTIONInthelastfewyearstherehajsbeenagrowinginterestinthenumericalsolutionofconstrainedoptimizationproblemsofturbinegovernedbytheEulerorNavier-Stokesequations.Developmelltofturbinecascadeswithoptimumaerodynamicefficiencyhaslongbeenadesignchalle... 相似文献
67.
In this paper, we propose a technique that uses thermal measurement results for improved accuracy in thermal simulation of electronic apparatus. Because the modeling of the electronic components in such apparatus has hitherto been very poor, the thermal simulation results cannot achieve the required accuracy. To solve this problem, we first represent a component as a set of cubic blocks with equivalent thermal conductivity and contact thermal resistance values, and then identify these values by using the thermal measurement results for the component. We regard the identification of parameters as an optimization problem that involves minimizing the difference between the predicted and measured results. To solve the problem, we combine genetic algorithms and a thermal simulation tool. Our technique was successfully applied to the construction of an accurate thermal model, which we validated by using thermal measurement results. © 2000 Scripta Technica, Heat Trans Asian Res, 30(1): 28–39, 2001 相似文献
68.
Xinchen Wang Yoshitomo Honda Jianxin Zhao Hidetoshi Morikuni Aki Nishiura Yoshiya Hashimoto Naoyuki Matsumoto 《International journal of molecular sciences》2021,22(22)
Various stresses latently induce cellular senescence that occasionally deteriorates the functioning of surrounding tissues. Nevertheless, little is known about the appearance and function of senescent cells, caused by the implantation of beta-tricalcium phosphate (β-TCP)—used widely in dentistry and orthopedics for treating bone diseases. In this study, two varying sizes of β-TCP granules (<300 μm and 300–500 μm) were implanted, and using histological and immunofluorescent staining, appearances of senescent-like cells in critical-sized bone defects in the calvaria of Sprague Dawley rats were evaluated. Parallelly, bone formation in defects was investigated with or without the oral administration of senolytics (a cocktail of dasatinib and quercetin). A week after the implantation, the number of senescence-associated beta-galactosidase, p21-, p19-, and tartrate-resistant acid phosphatase-positive cells increased and then decreased upon administrating senolytics. This administration of senolytics also attenuated 4-hydroxy-2-nonenal staining, representing reactive oxygen species. Combining senolytic administration with β-TCP implantation significantly enhanced the bone formation in defects as revealed by micro-computed tomography analysis and hematoxylin-eosin staining. This study demonstrates that β-TCP granules latently induce senescent-like cells, and senolytic administration may improve the bone-forming ability of β-TCP by inhibiting senescence-associated mechanisms. 相似文献
69.
The feasibility of using friction stir-processing technique as a microstructural refining method for preventing hydrogen-induced blisters of SK4 carbon steel alloy containing microstructure of hard cementite particles in a ductile ferrite matrix was examined. Amount and size of hydrogen-induced blisters decreased in the stirred layers with increasing rotation speed and completely disappeared when rotation speed attained 400 rpm because of the formation of a hard and fine microstructure consisting of pearlite, martensite, and retained austenite instead of that containing hard spheroidized cementite particles in a soft ferrite matrix. Interfaces between ferrite matrix and cementite particles were the preferential sites for the hydrogen blisters initiation. 相似文献
70.
Hidetoshi Kuramochi Daisuke Nakajima Sumio Goto Kazutoshi Sugita Wei Wu Katsuya Kawamoto 《Fuel》2008,87(13-14):3155-3157
In this study, HCl emission during the co-pyrolysis of demolition wood and a small amount of polyvinyl chloride (PVC) film (the Cl content of which ranged from 0.5% to 6% by weight) in an N2 atmosphere at elevated temperatures of up to 600 °C was measured using a laboratory-scale cylindrical batch reactor. In the pyrolysis experiments, HCl emission was reduced by the presence of wood. The effect of the primary constituents of wood (cellulose, hemicellulose, and lignin) on HCl emission was investigated by not only measuring HCl emission and Cl distribution to various phases during the co-pyrolysis of each constituent with PVC film but also by conducting thermogravimetric analysis of the constituents. This investigation first revealed that hemicellulose significantly reduced HCl emission by fixing most of the Cl molecules in a sample into pyrolyzed residue. 相似文献