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排序方式: 共有493条查询结果,搜索用时 31 毫秒
1.
2.
Nobuhiro Kumada Nobuo Ozawa Nobukazu Kinomura Fumio Muto 《Materials Research Bulletin》1985,20(5):583-589
Pyrochlores of A1?xHxTaO3·nH2O (A=Na,K) were prepared under the hydrothermal conditions. The values of x for these compounds were increased from 0.3 to 0.5 for A=Na and from 0.2 to 0.5 for A=K by treatment with the distilled water. The compounds with x<0.5 were decomposed to a mixture of NaTaO3 and Na2Ta4O11 for A=Na, or to a mixture of KTaO3 and a tetragonal tungsten bronze phase, and those with x=0.5 to a single phase of A2Ta4O11 at elevated temperatures. Below the decomposition temperatures, defect pyrochlores with oxygen vacancies, , were produced. They were hygroscopic, and in the case of A=K and x=0.5 the original phase was recovered by leaving in air for several hours. 相似文献
3.
Cooperative behavior of various agents in dynamic environment 总被引:5,自引:0,他引:5
Akihide Hiura Toshiya Kuroda Nobuhiro Inuzuka Ken-ichi Itoh Masashi Yamada Hirohisa Seki Hidenori Itoh 《Computers & Industrial Engineering》1997,33(3-4):601-604
The multi-agent model is a model in which agents with limited ability cooperate each other to accomplish a goal. In this paper, we introduce a multi-agent model in which agents are created to imitate real ants. There are two different type of agents, each type of which has a particular task. We designed agents to communicate each other by using pheromone considering noise. On this model, we observed cooperative behavior of agents and evaluated conditions to make an order of behavior in the model. 相似文献
4.
Namsin Park Takeyuki Shiraishi Kazuyoshi Kamisugi Yoshitaka Hara Keita Iizuka Takashi Kado Shuzi Hayase 《Journal of Applied Electrochemistry》2008,38(3):371-375
A direct ethanol fuel cell (DEFC), which is less prone to ethanol crossover, is reported. The cell consists of PtRu/C catalyst as the anode, Nafion® 117 membrane, and Ni–Co–Fe (NCF) composite catalyst as the cathode. The NCF catalyst was synthesized by mixing Ni, Co, and Fe complexes into a polymer matrix (melamine-formaldehyde resins), followed by heating the mixture at 800 °C under inert atmosphere. TEM and EDX experiments suggest that the NCF catalyst has alloy structures of Ni, Co and Fe. The catalytic activity of the NCF catalyst for the oxygen reduction reaction (ORR) was compared with that of commercially available Pt/C (CAP) catalyst at different ethanol concentrations. The decrease in open circuit voltage (Voc) of the DEFC equipped with the NCF catalysts was less than that of CAP catalyst at higher ethanol concentrations. The NCF catalyst was less prone to ethanol oxidation at cathode even when ethanol crossover occurred through the Nafion®117 film, which prevents voltage drop at the cathode. However, the CAP catalyst did oxidize ethanol at the cathode and caused a decrease in voltage at higher ethanol concentrations. 相似文献
5.
Nobukazu Kinomura Kiyoshi Onda Masayuki Kobayashi Nobuhiro Kumada Fumio Muto 《Journal of Materials Science》1989,24(5):1814-1818
Ion exchange of Na
x
WOP2O7 ·nH2O (x 1.4) prepared from WOP2O7 was attempted, using alkaline and alkaline earth ions. The degree of exchange was observed to be >50% at 90° C except for Mg2+. The basal spacing of ion-exchanged materials for the hydrated phase were dependent on the number of water molecules in the interlayer spaces, while those for the dehydrated phase increased with the size of ions in the interlayer spaces. The network of water molecules linked by the hydrogen bond in the interlayer spaces seems to determine the basal spacing. By the ion-exchange reaction,n-alkylammonium ions were intercalated into the interlayer spaces of Na
x
WOP2O7 ·nH2O (x 1.4) and Sn
x
H
y
WOP2O7 ·nH2O (2x +y 0.5). In spite of the difference in the charge density of the host layer, a similar arrangement of alkyl chains in the interlayer spaces resulted, and neutral amines were considered to be intercalated as well as ammonium ions. Direct reaction ofn-alkylamine with WOP2O7 produced an intercalation compound without reduction of tungsten. The arrangement of the amines in the interlayer spaces is similar to that supposed to the ion-exchanged derivatives when heated at 140° Cin vacuo. 相似文献
6.
7.
Nobuhiro Iwasa Tomoyuki Mayanagi Noriaki Ogawa Kentaro Sakata Nobutsune Takezawa 《Catalysis Letters》1998,54(3):119-123
Pd and Pt supported on ZnO, Ga2O3 and In2O3 exhibit high catalytic performance for the steam reforming of methanol, CH3OH+H2OCO2+3HH2, and the dehydrogenation of methanol to HCOOCH3, 2CH3OHHCOOCH3+2HH2. Combined results with temperature-programmed reduction (TPR) and XRD method revealed that Pd–Zn, Pd–Ga, Pd–In, Pt–Zn, Pt–Ga and Pt–In alloys were produced upon reduction. Over the catalysts having the alloy phase, the reactions proceeded selectively, whereas the catalysts having metallic phase exhibited poor selectivities. 相似文献
8.
Curing catalyst for epoxy resins was newly found. The catalyst consists of aluminum complex and silanol. Lack of one component of the pair does not cure epoxy resins. The epoxy resins cured with the catalyst are characterized by excellent electrical properties, especially at high temperature, due to the absence of strong acid species in the cured epoxy resin matrix. Heat-resistant property of the resin was also excellent. These properties were compared with those of epoxy resin cured with commonly used BF3 complex. 相似文献
9.
Tetsuto Kanzaki Yo Ishikawa Nobuhiro Morisaki Kohji Shirai Yasushi Saito Sho Yoshida 《Lipids》1987,22(10):704-710
Studies were done on changes in phospholipid content and fatty acid composition of phospholipids and on the role of the acylation
pathway in synthesis of phospholipids in the development of abnormal fatty acid composition in the glomeruli of rats 2 and
10 mo after induction of diabetes with streptozotocin. The proportions of individual phospholipids in the glomeruli of rats
were not changed 2 mo after induction of diabetes, but the proportion of phosphatidylethanolamine (PE) decreased and that
of sphingomyelin increased 10 mo after induction of diabetes. In contrast, in liver the proportion of PE was increased and
that of phosphatidylcholine was decreased. These results showed that changes of individual phospholipids in glomeruli were
time-dependent and tissue-specific. Two mo after induction of diabetes, the main change in the phospholipid fatty acid composition
of diabetic glomeruli was a decrease in arachidonic acid (AA); the main change in serum free fatty acids (FFA) was an increase
in linoleic acid (LA) and a decrease in AA. Ten mo after induction of diabetes, the main changes in the phospholipid fatty
acid composition of glomeruli were an increase in LA and a decrease in AA; the main change of the serum FFA composition was
a decrease in AA. Thus, the fatty acid composition of glomerular phospholipids was not directly correlated to that of the
serum in diabetic rats. Acyl-CoA synthetase and acyltransferase activities increased in diabetic glomeruli with either AA
or LA as substrate, but activity toward LA increased more at 2 mo after induction of diabetes. Acyl-CoA synthetase activity
increased in diabetic glomeruli with LA as substrate, but that did not change with AA as substrate at 10 mo after induction
of diabetes. Furthermore, acyltransferase activity decreased in diabetic glomeruli with AA as substrate, although that did
not change with LA as substrate at 10 mo after induction of diabetes. 相似文献
10.
Upper and lower critical solution temperatures have been determined for solutions of poly(ethylene glycol) in t-butyl acetate and water over the molecular weight range of Mη = 2.18 × 103 to ~1020 × 103. The phase diagram for solutions of poly(ethylene glycol) (Mη = 719 × 103) in t-butyl acetate was expressed as the ‘hour glass’ type, while the phase diagram for solution of poly(ethylene glycol) (Mη = 2.18 × 103 to ~2.29 × 103) in water was expressed as the ‘closed loop’ type. The value of the pressure dependence of the lower critical solution temperature in the poly(ethylene glycol) (Mη = 1020 × 103)/water system over the pressure range of 0 to ~50 atm was negligibly small and positive. 相似文献