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排序方式: 共有269条查询结果,搜索用时 15 毫秒
101.
Takatoshi Yoshimoto Kenta Yuki Ryo Teranishi Shinji Munetoh Kenji Kaneko 《Physica C: Superconductivity and its Applications》2011,471(23-24):1616-1620
Fe(Se1?xTex) thin films on (1 0 0) SrTiO3 were fabricated by a pulsed laser deposition method, and their crystal orientation, compositional shifts and superconducting properties were characterized by X-ray diffraction, scanning electron microscope combined with energy dispersive X-ray spectroscopy, etc. Compositional shift is one of the major problems during the fabrication of Fe(Se1?xTex) films due to its containing high volatile elements such as Se and Te. The compositional shifts were found dependent on the Ar background gas pressure (PAr), which was suppressed by the increase of PAr. In addition, it was revealed that the temperature window for the crystallization of the films was shifted to higher temperature region and wider temperature range with the increase of PAr. 相似文献
102.
Nishiwaki N Kobiro K Kiyoto H Hirao S Sawayama J Saigo K Okajima Y Uehara T Maki A Ariga M 《Organic & biomolecular chemistry》2011,9(8):2832-2839
A nitrile oxide containing a carbamoyl group is readily generated upon the treatment of 2-methyl-4-nitro-3-isoxazolin-5(2H)-one with water under mild reaction conditions, even in the absence of special reagents. The obtained nitrile oxide undergoes cycloaddition with dipolarophiles, alkynes and alkenes, to afford the corresponding isoxazol(in)es, which are useful intermediates in the synthesis of polyfunctionalized compounds. A plausible mechanism underlying the formation of the nitrile oxide is proposed, which involves an anomalous hydration/dehydration sequence. DFT calculations were also performed to support this mechanism. 相似文献
103.
Gwo S Lin MH He CL Chen HY Teranishi T 《Langmuir : the ACS journal of surfaces and colloids》2012,28(24):8902-8908
We report on bottom-up assembly routes for fabricating plasmonic structures and metamaterials composed of colloidal gold and silver nanostructures, such as nanoparticles ("metatoms") and shape-controlled nanocrystals. Owing to their well-controlled sizes/shapes, facile surface functionalization, and excellent plasmonic properties in the visible and near-infrared regions, these nanoparticles and nanocrystals are excellent building blocks of plasmonic structures and metamaterials for optical applications. Recently, we have utilized two kinds of bottom-up techniques (i.e., multiple-probe-based nanomanipulation and layer-by-layer self-assembly) to fabricate strongly coupled plasmonic dimers, one-dimensional (1D) chains, and large-scale two-dimensional/three-dimensional (2D/3D) nanoparticle supercrystals. These coupled nanoparticle/nanocrystal assemblies exhibit unique and tunable plasmonic properties, depending on the material composition, size/shape, intergap distance, the number of composing nanoparticles/nanocrystals (1D chains), and the nanoparticle layer number in the case of 3D nanoparticle supercrystals. By studying these coupled nanoparticle/nanocrystal assemblies, the fundamental plasmonic metamaterial effects could be investigated in detail under well-prepared and previously unexplored experimental settings. 相似文献
104.
105.
3,6‐Diethylphthalonitrile ( 3 ) with a tetrathiafulvalene (TTF) unit at 4,5‐positions was prepared from 4,5‐xylylenedithio‐3,6‐diethylphthalonitrile ( 1a ) via elimination of the xylylene group, connection of a carbonyl group to benzenedithiolate generated, and condensation of 4,5‐bis(methylthio)‐1,3‐dithiole‐2‐thione with benzo‐1,3‐dithiole‐2‐one ( 2‐O ) produced. A 1:1 mixture of phthalonitrile ( 3 ) and 4,5‐bis(benzylthio)‐3,6‐diethylphthalonitrile ( 1b ) was treated with lithium in n‐hexanol at 120°C to produce hexakis (benzylthio)mono(tetrathiafulvaleno)phthalocyanine ( 5 ), tetrakis(benzylthio)bis(tetrathiafulvaleno)phthalocyanine ( 6 ), and bis(benzylthio)tris(tetrathiafulvaleno)phthalocyanine ( 7 ). The structures of 5 , 6 , and 7 were determined by 1H NMR, FAB MS, MALDI‐TOF MS (matrix assisted laser desorption ionization time‐of‐flight mass spectrometry), and UV‐‐vis spectroscopy. Compound 6 is a mixture of trans and cis isomers ( 6‐ trans and 6‐ cis ). The UV‐‐vis spectrum of 5 measured in chloroform changed by addition of trifluoroacetic acid (TFA). The Q band absorption at λmax = 755 nm (chloroform) decreased in intensity and resulted in a new absorption at λmax = 740 nm (chloroform/TFA). The electrochemical properties of 5 , 6 , and 7 were determined by cyclic voltammetry using Ag/AgNO3 as a reference electrode. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:605–611, 2011; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20694 相似文献
106.
Sakamoto M Tanaka D Tsunoyama H Tsukuda T Minagawa Y Majima Y Teranishi T 《Journal of the American Chemical Society》2012,134(2):816-819
The structures of nanomaterials determine their individual properties and the suprastructures they can form. Introducing anisotropic shapes and/or interaction sites to isotropic nanoparticles has been proposed to extend the functionality and possible suprastructure motifs. Because of symmetric anisotropy, Platonic solids with regular polygon faces are one of the most promising nanoscale structures. Introduction of Platonic solid anisotropy to isotropic nanomaterials would expand the functionality and range of possible suprastructure motifs. Here, we demonstrate a novel strategy to obtain nano-Platonic solids through the face coordination of square porphyrins on an inscribed Au sphere with adequate size. The face coordination of the multidentate porphyrin derivatives, with four acetylthio groups facing the same direction, on the Au cluster encased the Au cluster in a Platonic hexahedron with six porphyrin faces. Transmission electron microscopy, mass spectrometry, elemental analysis, and scanning tunnelling microscopy were used to confirm the formation of the nano-Platonic hexahedron. 相似文献
107.
Yosuke Tanaka Tatsutoshi Shioda Takashi Kurokawa Junji Oka Kazuyuki Ueta Toshiharu Fukuoka 《Optical Review》2009,16(3):257-261
We propose a novel power-line-monitoring system using optical fibers for transmitting power as well as signal. The principle
is experimentally confirmed with a system composed of a monitoring side with a 1.5-μm laser diode, transmission line of a
single mode fiber, and a sensing side having an efficient photovoltaic (PV) cell, electrical junction sensor, and low power
liquid crystal optical modulator (LCOM). The PV cell generates the electrical power in the sensing side with a conversion
efficiency of 20%. The LCOM is driven with low power of less than 50 μW, modulates the laser light with a signal indicating
the power line condition, and transmits the optical signal. The developed sensing unit produces an optical signal having an
extinction ratio of 15 dB with low optical power of 1.8 mW. Five systems were in operation for two years, faithfully monitoring
the oil pressure in electrical cables every 20 min without incident. 相似文献
108.
Y. Ichikawa T. Kubo N. Aoi V. Banerjee A. Chakrabarti N. Fukuda H. Iwasaki S. Kubono T. Motobayashi T. Nakabayashi T. Nakamura T. Nakao T. Okumura H. J. Ong T. K. Onishi D. Suzuki H. Suzuki M. K. Suzuki T. Teranishi K. N. Yamada H. Yamaguchi H. Sakurai 《The European Physical Journal A - Hadrons and Nuclei》2009,42(3):375-378
$ \beta$ -decay spectroscopy on a T z = - 2 proton-rich nucleus 24Si was performed. The decay scheme of 24Si was reconstructed by the $ \beta$ -delayed $ \gamma$ -ray and proton measurements. Two $ \beta$ branches to the bound 11 + and 12 + states in 24Al were observed for the first time. The observation of the allowed transition firmly established the spin-parity assignment for the 12 + states. The branching ratios to the 11 + and 12 + states were determined to be 31(4)% and 23.9(15)%, respectively. The branching ratios to three unbound states in 24Al including a new level at 6.735MeV were also determined for the first time. The level structure of 24Al was compared with its mirror nucleus 24Na . The Thomas-Ehrman shift on the 12 + state indicates s -wave dominance in the state as well as a characteristic behavior of the weakly bound s -wave proton in 24Al . 相似文献
109.
Toshiharu Iwasaki Wataru Takarada Takeshi Kikutani 《Journal of Macromolecular Science: Physics》2017,56(9):709-723
The effect of heat sealing temperature on peelable heat seal strength (HSS) before and after the sterilization, often used industrially, was investigated for one of either polyethylene (PE) multilayered films with various inner sealant layers consisting of two high density PEs (HDPEs), a linear low density PE (LLDPE) or low density PE (LDPE). To attain similar HSS, heat sealing at a temperature close to the melting peak temperature (Tm-p) was needed only in the case of LDPE. Heat sealing behavior at higher temperatures, to attain higher HSS, was also investigated for HDPE and LDPE. High HSS, as well as suppressed reduction of HSS after the sterilization, was achieved for HDPE at a heat sealing temperature well below its Tm-p. An Increase of HSS with the increase of dwell time was also observed. On the other hand, for LDPE, high HSS and its stability after the sterilization were achieved only when the heat sealing temperature was increased to the value equivalent to its Tm-p. Improvement of the processing conditions for the shortening of the processing period was also investigated. For HDPE, higher sealing bar temperature was needed to gain similar HSS when the dwell time of the heat sealing was shortened from 4 to 2 s, whereas the attained maximum temperature at the interface was found to be similar. The characteristics of the heat sealed portion, judged from the relation between HSSs before and after the sterilization, were not affected by the dwell time of heat sealing, indicating that the shortening of the processing time by appropriate raising of the sealing bar temperature is possible. 相似文献
110.
Toshiharu Irisawa Kiiko Matsumoto Koichi Sudoh Hiroshi Iwasaki Makio Uwaha 《Surface science》2008,602(17):2880-2885
Smoothing of an atomically rough vicinal surface of SrTiO3 is studied by scanning tunneling microscope (STM) observation and by Monte Carlo (MC) simulation. A complex step pattern that resembles a two-dimensional phase separation pattern is observed on the surface. Analysis of the step pattern during annealing obtained by the STM in comparison with the MC simulation reveals an asymmetry of the relaxation pattern between islands and holes. The asymmetry is attributed to the difference of the mobility of an adatom and an atomic hole, and the asymmetry is enhanced by the step edge diffusion barrier. Values of an effective bond energy and an effective diffusion barrier as well as the surface diffusion coefficient are deduced from the relaxation pattern. 相似文献