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排序方式: 共有156条查询结果,搜索用时 15 毫秒
31.
The sensing characteristics of an amperometric NOx sensor with yttria-stabilized zirconia and a La-based perovskite-type oxide
sensing electrode were examined. La1-xSrxMO3 (M = Co, Mn, x = 0, 0.2, 0.4, 0.6) were synthesized using the spray pyrolysis method. The NO2 response of a sensor fabricated with La1-xSrxMnO3 increased with increasing amount of Sr, and the trend was in contrast to that of the sensors fabricated with La1-xSrxCoO3. LaSr0.2MnO3 was determined to be the most appropriate material for the sensor in terms of a high NO2 response and low O2 current. In order to discuss the effects of Sr addition to La-based perovskite oxides for the sensor, NO adsorption and desorption
properties of oxides and the relationship between the oxidation number of the B-site cation and Sr substitution were examined
using temperature-programmed desorption and X-ray photoelectron spectroscopy, respectively. 相似文献
32.
Karaki F Kabasawa Y Yanagimoto T Umeda N Firman Urano Y Nagano T Otani Y Ohwada T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(4):1127-1141
Although many organic/inorganic compounds that release nitric oxide (NO) upon photoirradiation (phototriggered caged-NOs) have been reported, their photoabsorption wavelengths mostly lie in the UV region, because X-NO bonds (X=heteroatom and metal) generally have rather strong π-bond character. Thus, it is intrinsically difficult to generate organic compounds that release NO under visible light irradiation. Herein, the structures and properties of N-pyramidal nitrosamine derivatives of 7-azabicyclo[2.2.1]heptanes that release NO under visible light irradiation are described. Bathochromic shifts of the absorptions of these nitrosamines, attributed to HOMO (n)-LUMO (π*) transitions associated with the nonplanar structure of the N-NO moiety, enable the molecules to absorb visible light, which results in N-NO bond cleavage. Thus, these compounds are innate organic caged-NOs that are uncaged by visible light. 相似文献
33.
Hiroaki Umeda Shiro Koseki Umpei Nagashima Michael W. Schmidt 《Journal of computational chemistry》2001,22(12):1243-1251
The quasi‐degenerate multireference second‐order perturbation theory (MRMP2) routines in the GAMESS suite of program codes have been parallelized using a distributed data interface (DDI). Two typical kinds of molecules were chosen for examination of parallelization speedup using one to eight PCs gathered as a cluster and connected by Fast Ethernet. The first example, in which total energies of several low‐lying electronic states have been obtained for niobium monohydride, give parallelization speedup of 7.15 when eight PCs were used as a cluster. The second example is the ground‐state total energy for a medium sized molecule, 4a,4b,8a,9a‐tetrahydro‐pyridino[1′,2′‐4,3]imidazo‐lidino[1,5‐a]pyridine. When distributed memory is employed, the parallelization speedup improves to 6.84 for the MRMP2 calculations when an eight‐PC cluster is used. These results demonstrate that our efforts to achieve the parallelization of MRMP2 routines have been successful. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1243–1251, 2001 相似文献
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35.
Kaoru Dokko Soichi Horikoshi Takashi Itoh Matsuhiko Nishizawa Takayuki Abe Minoru Umeda Isamu Uchida 《Journal of Solid State Electrochemistry》2002,6(3):188-193
A microelectrode technique was applied to investigate the electrochemical properties of LiMn2O4 particles at elevated temperatures. Cyclic voltammograms of LiMn2O4 were measured after the particles were exposed to the electrolytes. This technique results in rapid and precise evaluation
of the redox behavior of the materials. A significant capacity fading was observed in 1 M LiPF6/EC+PC electrolytic solution, which indicates that both LiMn2O4 and LiPF6 participate in the reaction to produce an inert material on the particle surface. Next, the capacity fading for two different
BET surface area particles were compared using 1 M LiPF6/EC+PC at 50 °C. The reaction was found not to be controlled by the surface area. Finally, a Li1.1Mn1.9O4 particle was employed. The fading in discharge was ca. 10% for 50 cycles even at 50 °C, which means that the partial substitution
of Mn in LiMn2O4 by Li substantially enhanced the capacity stability.
Electronic Publication 相似文献
36.
Selective introducing of aryl and amino groups: reaction of benzanthrone and organometallic reagents
Rui Umeda Teruaki Namba Tomohiro Yoshimura Masamichi Nakatsukasa Yutaka Nishiyama 《Tetrahedron》2013,69(5):1526-1531
The reaction of benzanthrone and aryl magnesium bromides produced 6-aryl-substituted benzanthrones in moderate to good yields. Similarly, 6-alkylaminobenzanthrones were selectively prepared by the reaction of benzanthrone and lithium alkylamides. In contrast, for the lithium arylamides, the arylamino groups were selectively introduced at the 4-position of the benzanthrone. 相似文献
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39.
Affoune AM Yamada A Umeda M 《Langmuir : the ACS journal of surfaces and colloids》2004,20(17):6965-6968
Surface morphology modification of the Nafion 117 membrane has been investigated by atomic force microscopy. The effects of water and methanol on the topography and structure of the surface were studied using the contact and tapping atomic force microscopy modes. Nafion topography considerably changes when samples absorb water. However, samples stored in methanol are characterized by flat surfaces. Surface modification was linked to an expansion phenomenon during the swelling of Nafion by solvents. Tapping-mode phase images showed that ionic and cluster domains are distinguishable from the surface of samples impregnated either in water or methanol. 相似文献
40.
Kenji Wada Yasuhiko Satomura Hiroshi Kamie Takafumi Kiuchi Hiromichi Horinaka Yoshio Cho Tokuo Umeda Kenji Nakamura 《Optical Review》2000,7(5):432-435
Aiming at the realization of optical computed tomography (optical CT), a compact system comprised of two cw-lasers and a detector was proposed for the extraction of quasi-straightforward propagating photons from scattered light transmitting through a scattering medium. The extraction ability of the system based on the sum-frequency generation technique was investigated using a standard scattering medium of Intralipid-10% aqueous solution and was found to be 78 dB in dynamic range. The optical CT image of absorbers placed in the scattering medium was successfully obtained with high contrast using the proposed system. 相似文献