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排序方式: 共有93条查询结果,搜索用时 31 毫秒
21.
Sakamoto Y Suzuki T Kobayashi M Gao Y Fukai Y Inoue Y Sato F Tokito S 《Journal of the American Chemical Society》2004,126(26):8138-8140
We report the synthesis and characterization of perfluoropentacene as an n-type semiconductor for organic field-effect transistors (OFETs). Perfluoropentacene is a planar and crystalline material that adopts a herringbone structure as observed for pentacene. OFETs with perfluoropentacene were constructed using top-contact geometry, and an electron mobility of 0.11 cm2 V-1 s-1 was observed. Bipolar OFETs with perfluoropentacene and pentacene function at both negative and positive gate voltages. The improved p-n junctions are probably due to the similar d-spacings of both acenes. Complementary inverter circuits were fabricated, and the transfer characteristics exhibit a sharp inversion of the output signal with a high-voltage gain. 相似文献
22.
Hiroyuki Noguchi Toshiyasu Kiyabu Kazuhiro Hasezaki Yasutoshi Noda 《Journal of Physics and Chemistry of Solids》2007,68(1):91-95
Pb- or Sn-doped Bi88Sb12 alloys were prepared by direct melting, quenching, and annealing. The Bi-Sb alloy phase was predominant in all samples. Pb or Sn atoms were distributed almost uniformly in Bi88Sb12, while some segregation was confirmed at the grain boundaries when Pb or Sn was involved heavily. The thermoelectric properties of these doped materials were investigated by measuring the Hall coefficient, electrical resistivity, and Seebeck coefficient between 20 K and 300 K. The Hall and Seebeck coefficients of Pb- or Sn-doped samples were positive at low temperatures, indicating that the doping element acted as an acceptor. Temperatures resulting in positive Hall and Seebeck coefficients further increased with increasing doping amount and with respect to the annealing process. As a result, a large power factor of 1.2 W/mK2 could be obtained in the 3-at% Sn-doped sample at 220 K, with a large positive Seebeck coefficient. 相似文献
23.
Miyazawa A Tanaka K Sakakura T Tashiro M Tashiro H Prakash GK Olah GA 《Chemical communications (Cambridge, England)》2005,(16):2104-2106
Retro-reductive aminations, direct transformations of amines to ketones, were catalyzed by Pd/C in water under microwave irradiation. 相似文献
24.
Stefan Kowarik Alexander Gerlach Alexander Hinderhofer Silvia Milita Francesco Borgatti Federico Zontone Toshiyasu Suzuki Fabio Biscarini Frank Schreiber 《固体物理学:研究快报》2008,2(3):120-122
We report high structural order in thin films of the organic semiconductor perfluoro‐pentacene (PFP), which is a candidate material for n‐type applications, deposited by vacuum sublimation on oxidized silicon wafers. Bragg reflections up to high order in both specular and grazing incidence geometries and a mosaicity of less than 0.01° demonstrate the well defined structure. The thin film entirely consists of crystallites with a structure close to the bulk phase without any contamination with a second phase. Real‐time X‐ray measurements show that PFP grows in a Stranski–Krastanov growth mode with the first monolayer wetting the substrate before 3d‐growth sets in during growth of the second monolayer. Implications for its use are discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
25.
Toshiyasu Inuzuka Yutaka Yamamoto Kaoru Yamada Daisuke Uemura 《Tetrahedron letters》2012,53(2):239-242
A polyol compound, amdigenol A, was isolated from the dinoflagellate Amphidinium sp. that adhered to the surface of the marine alga Digenea simplex. A structural elucidation was performed by 2D-NMR spectroscopy, degradation with a second generation Hoveyda–Grubbs catalyst and ESI-CID-MS/MS analyses. Amdigenol A consists of a C98-linear carbon backbone including two core structures of amphidinol analogs and is likely formed linearly by two amphidinol analogs. 相似文献
26.
This paper shows applications of the back-action evading amplifier, which amplifies a signal without degradation of the signal-to-noise ratio (SNR), to optical decoupling systems and clarifies the effects of the number of branches and the amplitude gain to SNR. As a result, it is shown that this concept provides an ideal optical system for networks with optical branches. 相似文献
27.
Iwanami K Choi JC Lu B Sakakura T Yasuda H 《Chemical communications (Cambridge, England)》2008,(8):1002-1004
The presence of the heterogeneous mesoporous Al-MCM-41 catalyst remarkably accelerated the cyanosilylation of various aldehydes and ketones with trialkylsilyl cyanide, giving the corresponding cyanohydrin silyl ethers in quantitative yields under mild reaction conditions. 相似文献
28.
Fanconi anemia (FA) is a rare genetic disorder characterized by aplastic anemia, cancer/leukemia susceptibility and cellular hypersensitivity to DNA crosslinking agents, such as cisplatin. To date, 12 FA gene products have been identified, which cooperate in a common DNA damage-activated signaling pathway regulating DNA repair (the FA pathway). Eight FA proteins form a nuclear complex harboring E3 ubiquitin ligase activity (the FA core complex) that, in response to DNA damage, mediates the monoubiquitylation of the FA protein FANCD2. Monoubiquitylated FANCD2 colocalizes in nuclear foci with proteins involved in DNA repair, including BRCA1, FANCD1/BRCA2, FANCN/PALB2 and RAD51. All these factors are required for cellular resistance to DNA crosslinking agents. The inactivation of the FA pathway has also been observed in a wide variety of human cancers and is implicated in the sensitivity of cancer cells to DNA crosslinking agents. Drugs that inhibit the FA pathway may be useful chemosensitizers in the treatment of cancer. Publication history: Republished from Current BioData's Targeted Proteins database (TPdb; http://www.targetedproteinsdb.com). 相似文献
29.
Jolanta WierzejskaManami Ohshima Toshiyasu InuzukaTetsuya Sengoku Masaki TakahashiHidemi Yoda 《Tetrahedron letters》2011,52(11):1173-1175
The first total synthesis of (+)-batzellaside B and its C8-epimer was completed from a known l-arabinose-derived tribenzyl ether in 22 steps with overall yields of 3.9% and 5.4%, respectively. The absolute configuration of (+)-batzellaside B was unambiguously determined to be 1S,3S,4S,5R,8S by the Mosher analysis of a synthetic intermediate prepared through a separate route. 相似文献
30.
[10]Cycloparaphenylene ([10]CPP) was selectively synthesized in four steps in 13% overall yield from commercially available 4,4'-diiodobiphenyl by using mono-I-Sn exchange, Sn-Pt transmetalation, I-Pd exchange, and subsequent oxidative coupling reactions. The single-crystal X-ray structure of [10]CPP is described. 相似文献