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81.
Fumitaka Wakabayashi Junko Kondo Kazunari Domen Chiaki Hirose 《Catalysis Letters》1993,21(3-4):257-264
Nitrogen adsorption on H-ZSM-5 and H-Y zeolites at low temperatures were studied by in situ FT-IR spectroscopy. For each zeolite, two absorption bands were observed at around 2334 and 2352 cm–1 in thev(NN) region and were assigned to thev(NN) mode of dinitrogen species adsorbed on Brønsted and Lewis acid sites of the zeolites, respectively. These results and previous results for H-mordenite suggest that dinitrogen serves as a probe of acid sites and its advantages as probe are discussed. 相似文献
82.
Disk lubricant additives A20H and C2 are Fomblin Z type perfluoropolyether with the hydroxyl end-group, –O–CF2–CH2–OH, at one end, and the cyclo-triphosphazene end-group, R5(PN)3–O–, at the other end. Here, R is an m-trifluoromethyl-phenoxy group for A20H and a trifluoroethoxy group for C2. These additives were examined for miscibility
with benzene, spin-off rate, water contact angle, and the diffusion rate over the carbon overcoat. It is revealed that A20H
adheres to the carbon overcoat spontaneously. The attractive interaction arises from the charge–transfer type interaction
between the aromatic rings of the phosphazene end and the graphitic regime of the carbon overcoat. No spontaneous adherence
occurs between the lubricant C2 and the carbon overcoat. A TOF-SIMS study of disks coated with A20H and C2, respectively,
with and without subsequent curing by short-UV (185 nm) was performed. It is revealed: (1) if presented with a low energy
electron, the phenoxy groups of A20H readily undergo the dissociative electron capture, while the trifluoroethoxy group does
not, and (2) photoelectrons generated by short-UV have little kinetic energy and the electron capture occurs only if an electrophilic
molecular sector is in intimate contact with the carbon. Thus, in the case of disks coated with A20H, UV-curing results in
detachment of a phenoxy group in contact with the carbon, generation of a radical center at the phosphorus atom and subsequent
formation of a bona fide chemical bond between the phosphor and the carbon overcoat. No reaction of consequence occurs when
disks coated with C2 are irradiated with short-UV. 相似文献
83.
Wakabayashi Y Upton MH Grenier S Hill JP Nelson CS Kim JW Ryan PJ Goldman AI Zheng H Mitchell JF 《Nature materials》2007,6(12):972-976
The question of how bulk electronic order is terminated at a surface is an intriguing one, and one with possible practical implications--for example in nanoscaled systems that may be characterized by their surface behaviour. One example of such order is orbital order, and in principle it should be possible to probe the termination of this order with surface X-ray scattering. Here, we report the first observation of the scattering arising from the termination of bulk orbital order at the surface of a crystal--so-called 'orbital truncation rods'. The measurements, carried out on a cleaved perovskite, La(0.5)Sr(1.5)MnO(4), reveal that whereas the crystallographic surface is atomically smooth, the orbital 'surface', which is observed through the atomic displacements caused by the orbital order, is much rougher, with a typical scale of the surface roughness of approximately 7 degrees A. Interestingly, the temperature dependence of this scattering shows evidence of a surface-induced second-order transition. 相似文献
84.
Takaaki Sakakibara Hiroshi Murase Eiichi Haginomori Seiji Wakabayashi Kunio Emoto Akihide Ogawa 《Electrical Engineering in Japan》1999,129(2):40-50
This paper describes the results of tests and discussions carried out to develop a system for partial discharge monitoring in GIS. They include the propagation characteristics of partial discharge pulses in each GIS component, as well as the test results obtained using an actual 300‐kV GIS. We also report the results of verification test on the GIS partial discharge monitoring and location system developed by the authors. © 1999 Scripta Technica, Electr Eng Jpn, 129(2): 40–50, 1999 相似文献
85.
Long‐chain monounsaturated fatty acid‐rich fish oil attenuates the development of atherosclerosis in mouse models 下载免费PDF全文
Zhi‐Hong Yang Toshihiro Sakurai Ye Chen Beatrice Emma‐Okon Bree Wilhite Daiju Fukuda Boris Vaisman Milton Pryor Yoshiyuki Wakabayashi Maureen Sampson Zu‐Xi Yu Akiko Sakurai Abdalrahman Zarzour Hiroko Miyahara Jiro Takeo Hiroshi Sakaue Masataka Sata Alan T. Remaley 《Molecular nutrition & food research》2016,60(10):2208-2218
86.
Eisuke Sakuma Ikuo Wada Takanobu Otsuka Kenjiro Wakabayashi Kinya Ito Tsuyoshi Soji Damon C. Herbert 《Microscopy research and technique》2012,75(12):1632-1638
We investigated the influence of testicular and adrenal androgens on the presence of gap junctions between folliculo‐stellate cells in the anterior pituitary glands of 60‐day‐old Wistar‐Imamichi strain male rats. The animals were separated into six groups: Group A served as the controls and had free access to a normal diet and water, Group B was given a normal diet and 0.9% NaCl for their drinking water as the controls of adrenalectomized groups, Group C was castrated, Group D was adrenalectomized, Group E was both castrated and adrenalectomized, and Group F was also both castrated and adrenalectomized. In addition, the animals of Group F were administered a dose of testosterone that is known to produce high physiological levels of the hormones in plasma. Five rats from each group were sacrificed 1, 2, 3, 4, 5, 6, and 7 days after their respective operation, and the anterior pituitary glands were removed and prepared for observation by transmission electron microscopy. We quantified the number of follicles and gap junctions and calculated the rate of occurrence as the ratio of the number of gap junctions existing between folliculo‐stellate cells per intersected follicle profile. Simultaneous removal of adrenal glands with castration resulted in a significantly decrease in the number of gap junctions, whereas the administration of testosterone to these rats compensated for this change. These observations indicate that the preservation of gap junctions between folliculo‐stellate cells is mainly dependent on androgens from both the testes and adrenal glands in adult male rats. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc. 相似文献
87.
Cyanopolyynes, H(CC)nCN (n = 3–6), were formed by laser ablation of carbon particles in liquid acetonitrile. The molecules were separated according to the size n and characterized by UV absorption spectroscopy, mass spectroscopy in combination with gas-chromatographic separation, and nuclear magnetic resonance (NMR) spectroscopy. For the study of nascent carbon cluster distribution during the growth of the long carbon chain molecules, isotopomer distribution was analyzed by NMR spectroscopy for the product molecules. Two cyanopolyynes of HC7N and HC9N were isolated from solutions after laser ablation of isotope-enriched carbon powder (99% 13C) in liquid acetonitrile, CH3CN, of natural isotopic abundance (1.1% 13C). With the observed chemical shift, δ, and spin–spin coupling constants, JCH and JCC, spectral simulation was made to determine relative abundance of possible isotopomeric forms for HC9N. We found that the isotope of 12C, mostly from solvent molecules, contributes substantially for the part of carbon in the cyano group, –CN, in HC9N. The isotopomer distribution observed for the sequence of H–CC–CC– was fairly explainable by a binomial, random distribution of the two carbon isotopes of 12C and 13C, reducing the concentration of 13C to 76–55%. 相似文献
88.
Weerathep Kueathaweekun Noppin Anantrasirichai Chawalit Benjangkaprasert Jintana Nakasuwan Toshio Wakabayashi 《ETRI Journal》2012,34(5):674-683
We propose a slot antenna consisting of a rectangular slot on the ground plane, fed by a microstrip line with a rectangular‐ring‐shaped tuning stub that can be deployed in ultra‐wideband (UWB) communication systems to avoid interference with wireless local area network (WLAN) communication. Our antenna can achieve a single band‐notched property from the 5 GHz frequency to the 6 GHz frequency owing to a controllable band notch that uses L‐ and J‐shaped parasitic elements. The antenna characteristics can be modified to tune the band‐notched property (4 GHz to 5 GHz or 6 GHz to 7 GHz) and the bandwidth of the band notch (1 GHz to 2 GHz). Furthermore, the shifted notch with enhanced width of the band notch from 1 GHz to 1.5 GHz is described in this paper. The UWB slot antenna and L‐ and J‐shaped parasitic elements also provide the band‐rejection function for reference in the WiMAX (3.5 GHz) and WLAN (5 GHz to 6 GHz) regions of the spectrum. Experiment results evidence the return loss performance, radiation patterns, and antenna gains at different operational frequencies. 相似文献
89.
Kenta Adachi Kensuke Honda Suzuko Yamazaki Tomoyuki Hirano Hiroshi Kurokawa Akinobu Wakabayashi Paul H. Kasai Katsuhiko Nakamae Hitoshi Iwabuki Koji Murakami 《Polymer Engineering and Science》2011,51(4):632-640
The vinyltrimethoxysilane‐grafted ethylene‐propylene copolymer/trifunctional methoxysilane (EPR‐g‐VTMS/RTMS) composites were prepared via in situ silica sol–gel reactions. Five trifunctional methoxysilane compounds (n‐hexyltrimethoxysilane, n‐decyltrimethoxysilane, n‐tetradecyltrimethoxysilane, n‐octadecyltrimethoxysilane, and phenyltrimethoxysilane) have been selected for this study. The water‐cross‐linked EPR‐g‐VTMS/RTMS composites were characterized by attenuated total reflectance‐Fourier transform infrared spectroscopy, gel content, solid‐state 29Si CP/MAS NMR, wide‐angle x‐ray scattering, tensile strength, and field emission scanning electron microscopy measurements. The type of RTMS additive has a substantial influence on the nature of siloxane band networks and eventually the mechanical tensile properties. This finding suggests that the interaction and/or entanglement between the EPR‐g‐VTMS matrix and the substituent of the RTMS additives are crucial for the modifying mechanical properties. Moreover, for the water‐cross‐linked EPR‐g‐VTMS/CnTMS (n = 6, 10, 14, and 18) composites, the joint evidence provided by attenuated total reflectance‐Fourier transform infrared spectroscopy, 29Si CP/MAS NMR, and wide‐angle x‐ray scattering results suggested the formation of ladder‐type poly(n‐alkyl silsesquioxane)s and the presence of the highly ordered structure with a thickness equal to the length of two n‐alkyl groups in all‐trans conformation. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers. 相似文献
90.
Abstract Chromium isotopes were fractionated by continuous extraction using dicyclohexano‐18‐crown‐6 as an extractant. This system was designed for accumulating isotope effect into the aqueous phase. After a long period of operation (~2 weeks), the Cr isotope ratios in the residual aqueous phase were precisely measured by using a multi‐collector thermal ionization mass spectrometer with the total evaporation technique. The analytical results showed a clear mass‐independent isotope fractionation. The mass‐independent property was consistent with that obtained from a batch extraction. The isotopic mass balance was verified to be preserved in the continuous extraction. The Bigeleisen's 1996 theory gave the consistent explanation on the Cr isotope effect, in which the mass‐independent isotope effect was identified to be the nuclear field shift effect. 相似文献