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排序方式: 共有221条查询结果,搜索用时 18 毫秒
51.
Ai Suzuki Katsuyoshi Nakamura Kotaro Okushi Nozomu Hatakeyama Hiromitsu Takaba Mark C. Williams 《Surface science》2009,603(20):3049-7652
The capability of theoretical durability studies to offer an efficient alternative methodology for predicting the potential performance of catalysts has improved in recent years. In this regard, multi-scale theoretical methods for predicting sintering behavior of Pt on various catalyst supports are being developed. Various types of Pt diffusions depending on support were confirmed by the micro-scale ultra accelerated quantum chemical molecular dynamics (UA-QCMD) method. Moreover, macro-scale sintering behavior of Pt/γ-Al2O3, Pt/ZrO2 and Pt/CeO2 catalysts were studied using a developed 3D sintering simulator. Experimental results were well reproduced. While Pt on γ-Al2O3 sintered significantly, Pt on ZrO2 sintered slightly and Pt on CeO2 demonstrated the highest stability against sintering. 相似文献
52.
Miho Kawai Teppei Nogami Kyohei Takano Akinori Okumura Katsuyoshi Nakazato Masahiko Ikeuchi 《Molecular Crystals and Liquid Crystals》2014,603(1):248-255
This paper proposes a self-assembly fabrication method of microwells and investigates the effect of surface treatment for the cell trapping. The target cell is unicellular cyanobacterium Synechocystis sp. strain PCC 6803, which has been widely investigated as a model organism for photosynthesis. The self-assembly monolayer of polystyrene particles (3.0 μm diameter) etched by reactive-ion etching was used as a template of polydimethylsiloxane molds. The well diameter in the mold could be controlled by the etching time. The cell-trapping efficiency was discussed with the viewpoint of hydrophilically treatment and poly-L-lysine treatment on the well arrays. 相似文献
53.
Tetsuya Yamada Kaito Kanda Yasuko Yanagida Gen Mayanagi Jumpei Washio Nobuhiro Takahashi 《Electroanalysis》2023,35(4):e202200103
An all-solid-state fluoride ion-selective electrode (ISE) was prepared using LaF3 single crystal with poly(3,4-ethylenedioxythiophene (PEDOT) as the solid contact layer. In contrast to polymer-based ISEs, crystalline membrane-based ISEs have not been used for all-solid-state device, thereby prohibiting the integration of ISEs on a chip. The all-solid-state fluoride ISE developed in this study exhibited superior sensitivity (−56.0±0.9 mV/dec) and selectivity compared to those of conventional inner filling solution ISE. The effects of PEDOT as a solid contact layer were analyzed using chronopotentiometry and electrochemical impedance spectroscopy, which revealed that PEDOT promoted electrode stability. The all-solid-state device can miniaturize the fluoride ISE and facilitate environmental, industrial, agricultural, and physiological monitoring. 相似文献
54.
Wanas AS Matsunami K Otsuka H Desoukey SY Fouad MA Kamel MS 《Chemical & pharmaceutical bulletin》2010,58(12):1596-1601
From the EtOAc and 1-BuOH fractions, three new ursane-type and four new lupane-type triterpenes, along with nine known glycosides and glycosyl esters of lupane-type were isolated from the leaves of Schefflera actinophylla. All the isolated compounds were obtained for the first time from this plant. The structures of the new triterpenes were determined through a combination of spectroscopic and chemical analyses. 相似文献
55.
Y. Tabata H. Kobayashi M. Washio Y. Yoshida N. Hayashi S. Tagawa 《Journal of Radioanalytical and Nuclear Chemistry》1986,101(2):163-169
A new picosecond pulse radiolysis Twin LINAC System has been constructed recently at Nuclear Engineering Research Laboratory at the University of Tokyo. The time resolution of the system is 20 ps and the system has a versatile capability for pulse radiolysis study. The outline of the facility is introduced. Some research carried out using the facility is presented. The examples are radiolysis of CCl4 and n-C21H44. 相似文献
56.
Masakazu Nishida Yoshio Hayakawa Masaki Matsui Katsuyoshi Shibata Hiroshige Muramatsu 《Journal of heterocyclic chemistry》1992,29(1):113-116
Diels-Alder reaction of 2,5-dialkyl-3,4-bis(trifluoromethyl)furan with hexafluoro-2-butyne gave 1,4-dialkyl-7-oxa-2,3,5,6-tetrakis(trifluoromethyl)bicyclohepta-2,5-diene. Irradiation (uv) of 1,4-diethyl-7-oxa-2,3,5,6-tetrakis(trifluoromethyl)bicyclohepta-2,5-diene afforded 1-ethyl-2,3,4,5-tetrakis(trifluoromethyl)-1,4-cyclopentadiene, ethyl 3-[l-ethyl-2,3,4,5-tetrakis(trifluoromethyl)-1,4-cyclopentadienyl] ketone, and 2,7-diethyl-3,4,5,6-tetrakis(trifluoromethyl)oxepin. 相似文献
57.
The radiation-crosslinked polyethersulfone (RX-PES) films were prepared by means of electron-beam irradiation under nitrogen atmosphere at 230 °C, where the temperature is around the glass transition temperature of PES (222 °C). The gel formation of RX-PES films was observed when the absorbed doses exceeded 300 kGy, which indicated the crosslinking structure formation. The G(S) of 0.10 and G(X) of 0.23 were calculated according to the Y-crosslinking mechanism. The irradiation was also performed at ambient temperature for comparison. There was no gel formation of the irradiated films even for the absorbed doses as high as 2250 kGy. The thermal properties of the original and irradiated PES films were measured by means of DSC and TGA analyses. The chemical structure of the original and the irradiated films was analyzed by means of FT-IR ATR and UV-vis spectroscopies. 相似文献
58.
Masakazu Nishida Yoshio Hayakawa Masaki Matsui Katsuyoshi Shibata Hiroshige Muramatsu 《Journal of heterocyclic chemistry》1991,28(2):225-229
The addition reaction of propionaldehyde to hexafluoro-2-butyne ( 1 ) under γ-ray irradiation gave trans-6,6,6-trifluoro-4-trifluoromethyl-4-hexen-3-one ( 2 ) and 4,5-bis(trifluoromethyl)octa-3,6-dione ( 3 ). The latter compound was treated with sulfuric acid to give 2,5-diethyl-3,4-bis(trifluoromethyl)furan ( 4a ). Several reactions, such as bromination, dehydrobromination and oxidation, were carried out to prepare derivatives of 4a . 相似文献
59.
Ruth Knibbe Kazuhiro Nogita John Drennan Tsuneyuki Noguchi Katsuyoshi Tatenuma Pou Liu Fumihito Arai Eiji Yashima Michiru Nishiwaki Shigeki Kato 《Journal of nanoparticle research》2007,9(6):1201-1204
Multi-wall carbon nanotubes (MWNTs) have a great commercial potential as electron field emitters, but suffer from fundamental
problems such as stability and brightness. By depositing the MWNTs with nano-sized ruthenium dioxide (RuO2) particles, a new high performance emitter has been developed. When compared to MWNTs, the MWNTs impregnated with 1–2 nm
sized RuO2 have superior and more efficient electrical characteristics. MWNTs supported by a silicon substrate showed a reduction in
the onset voltage from 5.4 to 4 V/μm after RuO2 impregnation. The long-term stability of the impregnated MWNTs is also demonstrated with only a 20% increase in applied voltage
required after 700 h operation at 40 mA/cm2. 相似文献
60.