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181.
Atsutoshi Yamada Yuki Watanabe Kyoko Noda Sumitaka Itoh Koji Ishihara Masahiko Inamo Refat Moustafa Hassan Hideo D. Takagi 《Journal of solution chemistry》2014,43(9-10):1479-1486
The reduction reaction of the Cu(II)–pitn complex (pitn = 1,3-di(pyridine-2-carboxaldimino)propane) by decamethylferrocene [Fe(Cp*)2] was examined in acetonitrile. The observed pseudo-first-order rate constants exhibited saturation kinetics with increasing excess amount of [Fe(Cp*)2]. Detailed analyses revealed that the reaction is controlled by a structural change prior to the electron transfer step, rather than a conventional bimolecular electron transfer process preceded by ion pair (encounter complex) formation. The rate constant for the structural change was estimated to be 275 ± 13 s?1 at 298 K (?H* = 33.3 ± 1.0 kJ·mol?1, ?S* = 86 ± 5 J·mol?1·K?1), which is the fastest among gated reactions involving CuN4 complexes. It was confirmed by EPR measurement and Conflex calculations that the dihedral angle between the two N–N planes is significantly large (40°) in solution whereas it is merely 17.14° in the crystal. 相似文献
182.
Co–Pd bimetallic alloy nanoparticle catalysts were prepared from CoCl2, Pd(OAc)2 and several capping agents with Li(C2H5)3BH. The nanoparticle catalysts were applied to the aerobic oxidation of a variety of alcohols in water to give the corresponding carbonyl products. The catalyst was magnetically recovered and reused for further oxidation. The nanoparticle catalysts were characterized with TEM, ICP, and XPS analyses. 相似文献
183.
The effect of oxidation pretreatment temperature(500 ~ 1 000 ℃) on the catalytic activity of Kovar applied on hydrocarbon CO2reforming was examined. Catalytic performance evaluation using tetradecane at 800 ℃ with 70 μmol/s CO2revealed 700 and 1 000 ℃ as the best pre-oxidation temperature in producing CO and H2,respectively. XRD and SEM-EDX analyses showed that a separate metal oxide layer composed of iron oxide(Fe2O3and F3O4),nickel,cobalt,and possibly their respective oxides started to form when oxidation was conducted at 700 ℃ or higher.The presence of iron enhanced the stability of nickel in the structure while the compact structure of Fe3O4resulted into the formation of a thick and rigid metal oxide layer on the surface of the Kovar tube. The strong physical bond between the metal oxide layer and Kovar tube provided the catalyst good mechanical strength and consequently good catalytic activity. 相似文献
184.
185.
The interrogation of fiber-Bragg-grating (FBG) sensors using a vertical-cavity surface-emitting laser (VCSEL) is discussed. A long-wavelength (1.54 μm) VCSEL was used as a wavelength-tunable source by variation in the current. Temperature stabilization was performed with a thermoelectric device. Characteristics of temperature and strain sensing were investigated. FBGs with different reflectivities were compared. For temperature sensing, the root-mean-square error in the measurement was reduced to 1/3 that without temperature stabilization. The dependence of the measurement error on the reflectivities of the FBGs was investigated. The measurement error was larger for FBGs with lower reflectivities in both temperature and strain sensing. Improvement on the sensing with low-reflectivity FBGs is discussed. 相似文献
186.
Yamazaki Kazuyoshi Hosaka Makoto Yamada Kenichiro Ogata Takeshi Shimada Kenichi 《Optical Review》2016,23(5):848-858
Optical Review - A precise and fast method for controlling the reference-beam angle of an angular-multiplexed holographic data storage system (HDSS)—to achieve larger capacity and faster... 相似文献
187.
Tsuchiya H Enoto T Yamada S Yuasa T Kawaharada M Kitaguchi T Kokubun M Kato H Okano M Nakamura S Makishima K 《Physical review letters》2007,99(16):165002
A report is made on a comprehensive observation of a burstlike gamma-ray emission from thunderclouds on the Sea of Japan, during strong thunderstorms on 6 January 2007. The detected emission, lasting for approximately 40 sec, preceded cloud-to-ground lightning discharges. The burst spectrum, extending to 10 MeV, can be interpreted as consisting of bremsstrahlung photons originating from relativistic electrons. This ground-based observation provides the first clear evidence that strong electric fields in thunderclouds can continuously accelerate electrons beyond 10 MeV prior to lightning discharges. 相似文献
188.
T. Yamada T. Nebiki S. Kishimoto H. Makino K. Awai T. Narusawa T. Yamamoto 《Superlattices and Microstructures》2007,42(1-6):68
Polycrystalline Ga-doped (Ga content: 4 wt%) ZnO (GZO) thin films were deposited on glass substrates at 200 C by a reactive plasma deposition with DC arc discharge technique. The dependences of structural and electrical properties of GZO films on thickness, ranging from 30 to 560 nm, were investigated. Carrier concentration, n, and Hall mobility, μ, increases with increasing film thickness below 100 nm, and then the n remains nearly constant and the μ gradually increases until the thickness reaches 560 nm. The resistivity obtained of the order of 10−4 Ω cm for these films decreases with increasing film thickness: The highest resistivity achieved is 4.4×10−4 Ω cm with n of 7.6×1020 cm−3 and μ of 18.5 cm2/V s for GZO films with a thickness of 30 nm and the lowest one is 1.8×10−4 Ω cm with n of 1.1×1021 cm−3 and μ of 31.7 cm2/V s for the GZO film with a thickness of 560 nm. X-ray diffraction pattern for all the films shows a hexagonal wurtzite structure with its strongly preferred orientation along the c-axis. Full width at half maximum of the (002) preferred orientation diffraction peak of the films decreases with increasing film thickness below 100 nm. 相似文献
189.
Manabu Yamada Muniyappan Rajiv Gandhi Yoshihiko Kondo Fumio Hamada 《Supramolecular chemistry》2014,26(7-8):620-630
The ability of chloroform solutions of p-diethylaminomethylthiacalix[4]arene 1 to extract platinum from HCl media was tested. As an ion-pair extractant, compound 1 had the highest platinum extraction ability among all the thiacalix[n]arene derivatives tested in this study. Compound 1 was a highly specific extractant for Pt(IV) ions from single-metal solutions and platinum-group metal solutions from automotive catalyst residue. Various conditions such as contact time, pH, concentration of 1, effect of chloride ions, effect of acidity and Pt(IV) concentration were studied. The distribution ratio of platinum ions (D) was calculated. The platinum complex stoichiometry ratio was obtained using slope analysis. The 1–Pt(IV) complex was characterised using X-ray photoelectron spectroscopy, FT-IR and 1H NMR. Finally, the Pt(IV) extraction percentage of compound 1 was compared with that of previously reported thiacalix[n]arene-based extractants. 相似文献
190.
Development of a New Benzylating Reagent Spontaneously Releasing Benzyl Cation Equivalents at Room Temperature
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Dr. Kohei Yamada Yuichi Tsukada Yukiko Karuo Dr. Masanori Kitamura Prof. Dr. Munetaka Kunishima 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(38):12274-12278
A new O‐benzylating reagent, that is, 4‐(4,6‐diphenoxy‐1,3,5‐triazin‐2‐yl)‐4‐benzylmorpholinium trifluoromethanesulfonate (DPT‐BM), has been developed. Benzyl cation equivalents are generated from DPT‐BM by dissolving the compound in a solvent at room temperature under non‐acidic conditions. The benzylation of various alcohols by using a combination of DPT‐BM and magnesium oxide provided the benzyl ethers in good yields. 相似文献