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91.
Masao Kaneko 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(3-4):357-365
A photosensing device was fabricated based on a photochemical electron transfer reaction. A graphite electrode was coated with bilayer membranes of polymer-pendant Ru(bpy)3 2+ and Prussian Blue (PB) to give a bilayer-coated device. It was irradiated with visible light in an aqueous electrolyte and the induced photocurrent was measured as a function of the applied potential. The excitation of PB was responsible for the anodic photocurrent, while the excitation of the Ru complex mainly induced the cathodic photocurrent by an electron-transfer mechanism. 相似文献
92.
A Nafion film containing tris(2,2′-bipyridine)ruthenium(II) as a luminescence probe was applied to photodetection of oxygen in a gas by utilizing the luminescence quenching by dioxygen. The linear Stern-Volmer plots of the emission intensity with respect to the oxygen concentration allowed quantitative determination of the oxygen. From the emission decay studied by a single-photon counting method, it was concluded that the quenching of the excited state Ru complex by oxygen proceeds by a conventional dynamic mechanism. 相似文献
93.
M. Matsuoka J. F. D. Chubaci J. P. Biersack S. Watanabe N. Kuratani K. Ogata 《辐射效应与固体损伤》2013,168(1-4)
Abstract Thin Ni films were prepared at room temperature by Ni metal vapour deposition and simultaneous irradiation by Ar ions with an energy of 2–20 keV. The reaction of Ni with Si during dynamic ion-beam mixing was studied. The fluences of the ion beam were 4.7 × 1017 and 8.9 × 1017 cm?2, and arrival rate ratios Ni/Ar were 9.7 and 5.1. Concentration profiles of Ni, Si, C, and O were analysed with Auger electron spectroscopy; the surface morphology and the crystalline structure were investigated with a cross-sectional scanning electron microscope and X-ray diffractometry. The theoretical profiles were calculated with the dynamic Monte Carlo simulation T-DYN for comparison with the experimentally obtained profiles. It was possible to observe the ballistic mixing effects and also thermally activated formation of nickel silicide. 相似文献
94.
Dr. Dinar Abdullin Dr. Hideto Matsuoka Dr. Maxim Yulikov Nico Fleck Dr. Christoph Klein Dr. Sebastian Spicher Dr. Gregor Hagelueken Prof. Dr. Stefan Grimme Prof. Dr. Arne Lützen Prof. Dr. Olav Schiemann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(37):8820-8828
Pulsed EPR dipolar spectroscopy (PDS) offers several methods for measuring dipolar coupling and thus the distance between electron-spin centers. To date, PDS measurements to metal centers were limited to ions that adhere to the high-field approximation. Here, the PDS methodology is extended to cases where the high-field approximation breaks down on the example of the high-spin Fe3+/nitroxide spin-pair. First, the theory developed by Maryasov et al. (Appl. Magn. Reson. 2006 , 30, 683–702) was adapted to derive equations for the dipolar coupling constant, which revealed that the dipolar spectrum does not only depend on the length and orientation of the interspin distance vector with respect to the applied magnetic field but also on its orientation to the effective g-tensor of the Fe3+ ion. Then, it is shown on a model system and a heme protein that a PDS method called relaxation-induced dipolar modulation enhancement (RIDME) is well-suited to measuring such spectra and that the experimentally obtained dipolar spectra are in full agreement with the derived equations. Finally, a RIDME data analysis procedure was developed, which facilitates the determination of distance and angular distributions from the RIDME data. Thus, this study enables the application of PDS to for example, the highly relevant class of high-spin Fe3+ heme proteins. 相似文献
95.
Tabito Ikezaki Reishi Matsuoka Kenichi Hatanaka Naoko Yoshie 《Journal of polymer science. Part A, Polymer chemistry》2014,52(2):216-222
We synthesized biobased poly(2,5‐furandimethylene succinate‐co‐butylene succinate) [P(FS‐co‐BS)] copolymers by polycondensation of 2,5‐bis(hydroxymethyl)furan, 1,4‐butanediol, and succinic acid. These copolymers could be crosslinked to form network polymers by means of a reversible Diels–Alder reaction with bis‐maleimide. The thermal properties, mechanical properties, and healing abilities of the P(FS‐co‐BS)s and the network polymers were investigated. The mechanical properties of the network polymers depended on the comonomer composition of the P(FS‐co‐BS)s and the maleimide/furan ratio in the network polymers. Some of the copolymers exhibited healing ability at room temperature, and their healing efficiency was enhanced by solvent or heat. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 216–222 相似文献
96.
97.
Sun-Chan Jeong Ichiro Katayama Hirokane Kawakami Yutaka Watanabe Hironobu Ishiyama Nobuaki Imai Yoshikazu Hirayama Hiroari Miyatake Masao Sataka Hiroyuki Sugai Satoru Okayasu Shin-Ichi Ichikawa Katsuhisa Nishio Shinichi Mitsuoka Takamitsu Nakanoya Takashi Hashimoto Takanori Hashimoto Masahito Yahagi 《Solid State Ionics》2009,180(6-8):626-630
The diffusion coefficients of Li in the NaTl-type Li intermetallic compound of β-LiGa have been measured by using a short-lived radioactive diffusion tracer. As the tracer, the α-emitting radioisotope of 8Li delivered as the energetic and pulsed beam from Tokai Radioactive Ion Accelerator Complex (TRIAC) was implanted into the β-LiGa compounds with the composition in the range of about 43 to 54 at.% Li. By analyzing the time-dependent yields of the α-particles measured according to the repetition cycle of the beam, the tracer diffusion coefficients were extracted over the wide range of Li composition. Abnormal composition-dependence of Li diffusion coefficients in β-LiGa was observed; the stoichiometric β-LiGa showed the highest diffusivity of Li. By referring to the composition-dependent diffusivity of Li in the iso-structural β-LiAl and β-LiIn, we could identify the abnormal diffusion of Li in very Li-poor composition of β-LiGa. The anomaly has been discussed qualitatively in terms of the formation of defect complex and the interaction between the constitutional defects. 相似文献
98.
Hirohito Ikeda Yukiko Sano Tomonori Matsubara Mitsunobu Kawahara Miho Yukawa Masao Fujisawa Eiji Yukawa Hatsumi Aki 《Journal of Thermal Analysis and Calorimetry》2013,113(3):1135-1138
Propericiazine (PCZ) is an antipsychotic agent used for the treatment and the prevention of relapse of schizophrenia. We found that when an oral solution containing PCZ was mixed with a green tea drink, the residual content of PCZ was reduced by forming an insoluble complex between PCZ and tea polyphenol. In this study, the mechanism underlying the incompatibility of PCZ with green tea polyphenol (GTP) in the solution was clarified by isothermal titration microcalorimetry (ITC). Both solutions of 27.4 mM PCZ and 2.2 mM (?)-epigallocatechin gallate (EGCg), which is a main ingredient of GTP, were mixed and then PCZ in the filtrate was reduced to approximately 60 %. According to measurement at 298 K by ITC, PCZ formed an insoluble complex with EGCg at an associate constant (K) of 4.75 × 102 M?1 exothermically, ΔH = ?40.0 kJ mol?1. When (?)-epicatechin gallate (ECg) was used as the GTP, PCZ interacted with ECg with K and ΔH values of 3.74 × 102 M?1 and ?22.1 kJ mol?1, respectively. On the other hand, little heat of the reaction between PCZ and (?)-epigallocatechin or (?)-epicatechin was observed. The results indicated that the main reason for this incompatibility was the formation of an insoluble complex by PCZ and a gallate-type GTP such as EGCg and ECg in the aqueous solution. 相似文献
99.
Takayoshi Kimura Tasunori Suzuki Keisuke Takata Akina Soga Yutsa Nomoto Tadashi Kamiyama Yousuke Nakai Hideo Matsui Masao Fujisawa 《Journal of Thermal Analysis and Calorimetry》2013,113(3):1467-1474
The molar excess enthalpies of eight systems of butylamines + propanols were determined at 298.15 K using a twin-microcalorimeter. All excess enthalpies were exothermic and large. An equilibrium constant K 1 expressed in terms of mole fractions and standard thermodynamic properties of formation (Δf H, Δf G, Δf S) of 1:1 complex were evaluated by ideal mixtures of monomeric molecules and their associated complexes. Concentration dependence of the FT-Raman spectrum showed systematic changes of bands. Spectroscopic considerations based on this and ab initio calculations on molecules were performed at the Mp2/6-311G(d,p) level of theory. Interaction energies between butylamine and propanol were calculated by the supermolecular and NBO methods. The results were discussed with previous results to clarify the steric and positional effect of the amino and hydroxyl group. 相似文献
100.
Dipalmitoylphosphatidylcholine was synthesized in a good yield by the reaction of L-α-glycerophosphorylcholine with 1-palmitoylimidazole in the presence of DBU. Polymer-supported 1-palmitoylimidazole moiety also could be used as the acylating reagent, though the yield of the choline was moderate. 相似文献