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81.
Electrical conductivity of non-doped (CH)x decreases a little and its activation energy increases a little by the electron beam irradiation. The increase of the electrical conductivity of the irradiated (CH)x by I2 doping is not so remarkable compared with that of non-irradiated (CH)x. The conductivity of heavily irradiated (CH)x is very low even after halogen dopings.On the other hand, the effect of the electron beam irradiation on the conductivity of previously I2 doped (CH)x is much less compared with that doped after the electron beam irradiation. These results are explained tentatively by the role of I2 molecules in the initial stage of radiolysis and the suppression of the cross-linking. 相似文献
82.
83.
Kazunori Kurosawa Masahiko Suenaga Takahiko Inazu Tamotsu Yoshino 《Tetrahedron letters》1982,23(50):5335-5338
The title compounds, I, were synthesized by the dialkylation of TosMIC, II, with appropriate bis (halomethyl) compounds, III, under phase-transfer condition, followed by acid hydrolysis. 相似文献
84.
85.
S. Morita S. B. Lee A. A. Zakhidov K. Yoshino 《Molecular Crystals and Liquid Crystals》2013,570(1):839-846
Abstract We have found recently that thin film layered heterojunction between C60 and conducting polymer, like poly(3-alkylthiophene) (PAT) shows a photovoltaic effect due to photoinduced charge transfer at the interface. Here we describe two other examples of such photocells in RO-PPV/C60 and PPP/C60 heterojunctions and study their spectral characteristics. Contrary to conventional inorganic semiconductor p-n junction photocells, the C60-PAT junction can be rather viewed as molecular donor-acceptor (D-A) type photocell in which the processes of photogeneration and separation of charge carriers are quite distinct. In a p-n junction free electron-hole pairs are known to be primarily photogenerated at interband transition and then separated in the internal electric field of the barrier, while in D-A molecular photocell mainly neutral excitons are first created by light, with charges being primarily separated at the narrow interface region due to D-A type intermolecular charge transfer interactions. We analyze how this processes depend on the wavelength of the pumping light and on the polarity and magnitude of the applied voltage. 相似文献
86.
Hirofumi Matsuhata Hirotaka Yamaguchi Tamotsu Yamashita Toshiaki Tanaka Bin Chen Takashi Sekiguchi 《哲学杂志》2013,93(15):1674-1685
Shockley partial dislocations in 4H-SiC were observed using monochromatic synchrotron X-ray topography with a grazing-incidence Bragg-case geometry, that is, Berg–Barrett topography. The contrast of partial dislocations at the edges of Shockley-type stacking faults is discussed in terms of whether they have C- or Si-core edge components, or screw components. The dissociated state of basal-plane dislocation is discussed on a basis of the stacking sequence for basal-planes in the 4H-SiC crystal structure. It is expected that the results obtained in this study will be useful for characterizing Shockley-type stacking faults in Berg–Barrett topography. 相似文献
87.
Experimental investigations on the ferroelectric liquid crystal, R-4′(1-butoxycarbonyl-1-ethoxy) phenyl 4-(4-octyloxy phenyl) benzoate (1BC1EPOPB) of large spontaneous polarization (P S(+) = 240?nC?cm?2), using dielectric and calorimetric techniques, are reported. The temperature range of 25.0–125.0°C has been chosen for dielectric measurements. Dielectric dispersion studies are carried out in the temperature range 45.0–75.0°C and in the frequency range 2?Hz to 2?MHz for the smectic A, smectic C* and smectic X phases. A new phase called ‘smectic X’ has been found around 56.3°C. The transition temperatures identified by the dielectric dispersion studies for different phases and those given by DSC techniques are in close agreement. 相似文献
88.
Masafumi Yoshino 《偏微分方程通讯》2013,38(9-10):1925-1950
We study the global solvability of Monge-Ampère equations of mixed type by "blowing up" the problem onto the torus embedded at the singular point of the equations 相似文献
89.
Simultaneous Induction of Axial and Planar Chirality in Arene–Chromium Complexes by Molybdenum‐Catalyzed Enantioselective Ring‐Closing Metathesis 下载免费PDF全文
Prof.Dr. Ken Kamikawa Dr. Sachie Arae Dr. Wei‐Yi Wu Chihiro Nakamura Prof.Dr. Tamotsu Takahashi Prof.Dr. Masamichi Ogasawara 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(13):4954-4957
The molybdenum‐catalyzed asymmetric ring‐closing metathesis of the various Cs‐symmetric (π‐arene)chromium substrates provides the corresponding bridged planar‐chiral (π‐arene)chromium complexes in excellent yields with up to >99 % ee. With a bulky and unsymmetrical substituent, such as N‐indolyl or 1‐naphthyl, at the 2‐positions of the η6‐1,3‐diisopropenylbenzene ligands, both biaryl‐based axial chirality and π‐arene‐based planar chirality are simultaneously induced in the products. The axial chirality is retained even after the removal of the dicarbonylchromium fragment, and the chiral biaryl/heterobiaryl compounds are obtained with complete retention of the enantiopurity. 相似文献
90.
Recyclable carbon fiber‐reinforced plastics (CFRP) containing degradable acetal linkages: Synthesis,properties, and chemical recycling 下载免费PDF全文
Ayaka Yamaguchi Tamotsu Hashimoto Yoshinori Kakichi Michio Urushisaki Toshikazu Sakaguchi Kazumasa Kawabe Keiichi Kondo Hirohumi Iyo 《Journal of polymer science. Part A, Polymer chemistry》2015,53(8):1052-1059
Two epoxy resins containing degradable acetal linkages were synthesized by the reaction of cresol novolak‐type phenolic resin (CN) with vinyl ethers containing a glycidyl group [cyclohexane dimethanol vinyl glycidyl ether (CHDMVG) and 4‐vinyloxybutyl glycidyl ether (VBGE). Carbon fiber‐reinforced plastics (CFRPs) were prepared by heating laminated prepreg sheets with CN‐CHDMVG resin (derived from CN and CHDMVG) and CN‐VBGE resin (derived from CN and VBGE), in which carbon fibers are impregnated with epoxy resins containing curing agents [dicyandiamide (DICY)] and curing accelerator [3‐(3,4‐dichlorophenyl)‐1,1‐dimethylurea (DCMU)]. CN‐CHDMVG‐based CFRPs and CN‐VBGE‐based CFRPs exhibited almost the same tensile strength as the conventional bisphenol‐A‐based CFRPs. CN‐CHDMVG‐based CFRPs and CN‐VBGE‐based CFRPs underwent smooth breakdown with the treatment of hydrochloric acid in tetrahydrofuran at room temperature for 24 h to regenerate strands of carbon fibers. The surface conditions of the recovered carbon fibers had little changes during degradation and recovery processes on the basis of scanning electron microscopy (SEM) and X‐ray photoelectron spectroscopy (XPS). The recovered carbon fibers exhibited almost the same tensile strength as virgin carbon fibers and hence would be reused for the production of CFRPs. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1052–1059 相似文献