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981.
982.
Takeshi Yasuda Yuki Shinohara Takaaki Matsuda Liyuan Han Tsutomu Ishi‐i 《Journal of polymer science. Part A, Polymer chemistry》2013,51(12):2536-2544
We synthesized and characterized three new amorphous dithienylbenzothiadiazole (TBT)‐triphenylamine (TPA) polymers for application in bulk‐heterojunction (BHJ) organic photovoltaic (OPV) cells. Poly(3HTBT‐TPA) has hexyl side chains on the thienyl groups (pointing toward the benzothiadiazole (BTD) unit), and poly(4HTBT‐TPA) has hexyl side chains on the thienyl groups (pointing outward from the BTD unit). The incident photon to current conversion efficiencies (IPCEs) in the region from 550 to 650 nm for the OPV cells prepared using poly(4HTBT‐TPA) were higher than those for the OPV cells prepared using poly(3HTBT‐TPA) because the absorption spectrum for the poly(4HTBT‐TPA) has a slightly red‐shifted absorption edge. We also demonstrated that the poly(4HTBT‐TPA)‐based OPV performance is independent of the fabrication process, so using an amorphous film to fabricate BHJ OPV cells offers great advantages over using a polycrystalline film in terms of the high reproducibility of the OPV performance. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2536–2544 相似文献
983.
Qinghui Li Rina Suzuki Yuki Ono Izumi Nakai Keiichi Tanaka Satoshi Nakayama Haruo Takahashi 《X射线光谱测定》2009,38(5):369-375
Suspended particulate matter (SPM) collected in the urban area of Tokyo was analyzed using a transition edge sensor (TES) microcalorimeter x‐ray detector mounted on a FE‐SEM system. This prototype microcalorimeter spectrometer with an energy resolution of 19 eV identified some severe peak overlaps in the spectra measured by the traditional Si(Li) solid state detector, including S Kα with Pb Mα, Zn Lα with Na Kα, and Ti Kα with Ba Lα. In addition, the TES microcalorimeter showed good spatial resolution for the microanalysis of SPM. The focused ion beam(FIB) was successfully applied to fabricate a cross section of a single SPM particle. The chemical compositonal difference between surface and inner parts, and among different surface parts of the SPM was also determined. Through combination of the FIB technique and the TES microcalorimeter, we achieved a better understanding of the SPM. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
984.
Optimized experimental conditions of infrared p-polarized multiple-angle incidence resolution spectrometry (p-MAIRS) for the analysis of ultrathin films on glass have been explored. When the original MAIRS technique is employed for thin-film analysis on a substrate of germanium or silicon, which exhibits a high refractive index, an established experimental condition without optimization can be adapted for the measurements. On the other hand, the p-MAIRS technique that has been developed for analysis on a low-refractive-index material requires, however, optimization of the experimental parameters for a 'quantitative' molecular orientation analysis. The optimization cannot be performed by considering only for optics in the spectrometer, but for optics concerning the substrate should also be considered. In the present study, an optimized condition for infrared p-MAIRS analysis on glass has been revealed, which can be used for quantitative molecular orientation analysis in ultrathin films on glass. 相似文献
985.
El Sayed H. El Ashry Ahmed Mousaad Juji Yoshimura Katsuhiko Ueno 《Journal of carbohydrate chemistry》2013,32(4):519-526
Abstract X-Ray crystallography confirmed the L-erythro-config-uration of 3-(2-0-acetyl-1, 3-dibromo-1, 3-dideoxy-glycerol-l-yl)- 1-phenyl-2-pyrazo line-4, 5-dione 4 -(phenylhydrazone) that results from the reaction of hydrogen bromide in acetic acid with the corresponding of L-threo-glycerol-1-yl- analog. 相似文献
986.
Shunya Takahashi Yuki Akita Takemichi Nakamura Hiroyuki Koshino 《Tetrahedron: Asymmetry》2012,23(13):952-958
The total synthesis of curvulone B was achieved, and its absolute configuration unambiguously established, as had been determined by TD-DFT ECD calculations on the computed solution conformers. Key features of the synthesis were an olefin cross-metathesis of an α,β-unsaturated ketone as a common key building block with (R)-6-triethylsilyloxyhept-1-ene, and an intramolecular oxy-Michael addition of the hydroxyl enone obtained therefrom. An intermolecular metathesis of the enone with (S)-5-benzyloxyhept-ene also enabled us to prepare a proposed structure for dothiorelone B, thus leading to the confirmation of the structural revision of phomopsin A, a novel nine-membered cyclic phenol ether. 相似文献
987.
Given a substitution σ ond letters, we define itsk-dimensional extension,E
k (σ), for 0≤k≤d. Thek-dimensional extension acts on the set ofk-dimensional faces of unit cubes inR
d with integer vertices. The extensions of a substitution satisfy a commutation relation with the natural boundary operator:
the boundary of the image is the image of the boundary. We say that a substitution is unimodular (resp. hyperbolic) if the
matrix associated to the substitution by abelianization is unimodular (resp. hyperbolic). In the case where the substitution
is unimodular, we also define dual substitutions which satisfy a similar coboundary condition. We use these constructions
to build self-similar sets on the expanding and contracting space for an hyperbolic substitution. 相似文献
988.
Kana Matsudaira Yuki Mimura Junichi Hotei Prof. Dr. Shigeyuki Yagi Dr. Ken-ichi Yamashita Prof. Dr. Michiya Fujiki Prof. Dr. Yoshitane Imai 《化学:亚洲杂志》2021,16(8):926-930
The magnetic circularly polarized luminescence (MCPL) and photoluminescence (PL) spectra of achiral (2,3,7,8,12,13,17,18-octaethylporphyrinato)platinum(II), PtOEP , and [2-(4′,6′-difluorophenyl)pyridinato-N,C2′]platinum(II) acetylacetonate-O,O, F2-ppyPt(acac) , in toluene and dichloromethane solutions were recorded under an external magnetic field of 1.6 T with N-up and S-up Faraday geometries. The MCPL signs of PtOEP and F2-ppyPt(acac) were controlled solely by changing the N-up and S-up geometries. The MCPL/PL wavelengths of F2-ppyPt(acac) in solutions were varied by the ratio of the monomeric and excimeric species. 相似文献
989.
Tatsuki Tahara Yuki Shimozato Peng Xia Yasunori Ito Takashi Kakue Yasuhiro Awatsuji Kenzo Nishio Shogo Ura Toshihiro Kubota Osamu Matoba 《Optical Review》2013,20(1):7-12
Parallel phase-shifting digital holography (PPSDH) is a technique of single-shot phase-shifting digital holography. We found that there are two problems with this technique. (1) Some extraneous noises caused by the intensity unevenness of the reference wave become slightly superimposed on the object image. (2) The conjugate image cannot be completely removed. This is because the object wave causes the phase-shift error by illuminating an image sensor with a large incident angle. To solve these problems, we propose an algorithm for removing residual 0th-order diffraction and conjugate images in PPSDH. In the proposed algorithm, we modified phase-shifting interferometry in order to work through the unevenness of the intensity distribution and applied the Fourier transform technique to PPSDH to remove the residual conjugate image. The effectiveness of the proposed algorithm was experimentally verified. 相似文献