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931.
D. Watanabe T. Yoshida C. Allen T. Tanabe 《Journal of Radioanalytical and Nuclear Chemistry》2007,272(3):461-465
This work is devoted to enhance gamma-ray radiolysis of CO2 with the assistance of coexisting metal materials. It is found that lower energy electrons which are generated through interactions
of γ-photons with the coexisting metal materials and ejected to CO2 gas actually enhance decomposition of CO2 to produce CO. The increment of CO production agrees well with the increment of the deposited energy in CO2, given by the lower energy electrons emitted from the materials, which is calculated by a numerical simulations code MCNP.
It is also suggested that the volumetric decomposition of CO2 dominates the decomposition at the material’s surface. 相似文献
932.
Yoko Tatewaki Dr. Tatsuya Hatanaka Ryo Tsunashima Dr. Takayoshi Nakamura Prof. Mutsumi Kimura Prof. Hirofusa Shirai Prof. 《化学:亚洲杂志》2009,4(9):1474-1479
Tetrathiafulvalenes (TTF) S‐TTF and R‐TTF having four chiral amide end groups self‐organize into helical nanofibers in the presence of 2,3,5,6‐tetrafluoro‐7,7′,8,8′‐tetracyano‐p‐quinodimethane (F4TCNQ). The intermolecular hydrogen bonding among chiral amide end groups and the formation of charge‐transfer complexes results in a long one‐dimensional supramolecular stacking, and the chirality of the end groups affects the molecular orientation of TTF cores within the stacks. Electronic conductivity of a single helical nanoscopic fiber made of S‐TTF and F4TCNQ is determined to be (7.0±3.0)×10?4 S cm?1 by point‐contact current‐imaging (PCI) AFM measurement. Nonwoven fabric composed of helical nanofibers shows a semiconducting temperature dependence with an activation energy of 0.18 eV. 相似文献
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T. Yamada S. A. E. Boyer T. Iyoda H. Yoshida J. -P. E. Grolier 《Journal of Thermal Analysis and Calorimetry》2007,89(1):9-12
The effects of nitrogen (N2) pressure on amphiphilic di-block copolymer, PEO114-b-PMA(Az)40, were investigated by scanning transitiometry. The isotropic transition temperature increased with the increase of pressure
above 20 MPa. The hydrostatic pressure effects evaluated with the Clapeyron equation were smaller than the value obtained
by mercury as a pressurizing medium because the amount of absorbed gas decreases the volume change at the isotropic transition. 相似文献
936.
Poly[2-(perfluorooctyl)ethyl acrylate-co-poly(ethylene glycol) methacrylate], P(POA-co-PEGm) was prepared as a new surfactant for scCO2. The random copolymer was obtained by the radical polymerization of 2-(perfluorooctyl)ethyl acrylate (POA) and poly(ethylene
glycol) methacrylate (PEGm) in DMF. The molar ratio of the POA and PEGm units in the copolymer was POA/PEGm = 0.972/0.028
by 1H NMR. The molecular weight and molecular weight distribution were estimated by size exclusion chromatography to be Mn = 133,000
and Mw/Mn = 8.25, respectively. It was suggested that the copolymer formed micellar aggregates with the cores of the PEGm
chains in scCO2, based on the analyses of the copolymer in hexafluorobenzene by 1H NMR and dynamic light scattering. The copolymer was soluble in scCO2 and had a cloud point at a much higher pressure than the critical pressure. It was found that the copolymer solubilized CO2-insoluble proteins such as bovine serum albumin and subtilisin Carlsberg in scCO2. The solubility of the copolymer was not influenced by the presence of the proteins; however, the solubility decreased in
the presence of a small amount of water along with the protein. The activity of the subtilisin slightly decreased when only
placed in scCO2, whereas a marked decrease in the activity was observed for the subtilisin in the presence of the copolymer in scCO2. The subtilisin activity decreased as the CO2 pressure increased. 相似文献
937.
N Mataga H Chosrowjan Y Shibata N Yoshida A Osuka T Kikuzawa T Okada 《Journal of the American Chemical Society》2001,123(49):12422-12423
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