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排序方式: 共有920条查询结果,搜索用时 15 毫秒
1.
Taro Shimonosono Yoshihiro Hirata Mubin Changgan Syohei Kamei Rina Tokaiya Soichiro Sameshima Toshifumi Yoshidome Katsuhiko Yamaji 《Ceramics International》2018,44(8):8904-8912
This paper reports the performance of porous Gd-doped ceria (GDC) electrochemical cells with Co metal in both electrodes (cell No. 1) and with Ni metal in the cathode and Co metal in the anode (cell No. 2) for CO2 decomposition, CH4 decomposition, and the dry reforming reaction of a biogas with CO2 gas (CH4 + CO2 → 2H2 + 2CO) or with O2 gas in air (3CH4 +?1.875CO2 +?1.314O2 → 6H2 +?4.875CO +?0.7515O2). GDC cell No. 1 produced H2 gas at formation rates of 0.055 and 0.33?mL-H2/(min?m2-electrode) per 1?mL-supplied gas/(min?m2-electrode) at 600?°C and 800?°C, respectively, by the reforming of the biogas with CO2 gas. Similarly, cell No. 2 produced H2 gas at formation rates of 0.40?mL-H2/(min?m2) per 1?mL-supplied gas/(min?m2) at 800?°C from a mixture of biogas and CO2 gas. The dry reforming of a real biogas with CO2 or O2 gas at 800?°C proceeded thermodynamically over the Co or Ni metal catalyst in the cathode of the porous GDC cell. Faraday's law controlled the dry reforming rate of the biogas at 600?°C in cell No. 2. This paper also clarifies the influence of carbon deposition, which originates from CH4 pyrolysis (CH4 → C + 2H2) and disproportionation of CO gas (2CO → C + CO2), on the cell performance during dry reforming. The dry reforming of a biogas with O2 molecules from air exhibits high durability because of the oxidation of the deposited carbon by supplied air. 相似文献
2.
Lussier Isabelle; Derevensky Jeffrey L.; Gupta Rina; Bergevin Tanya; Ellenbogen Stephen 《Canadian Metallurgical Quarterly》2007,21(2):165
The study of resilient children has overturned many deficit-focused models concerning the ontogenesis of children raised in adversity. This study explored the relationship between risk and protective factors, resilience, and youth gambling behavior. More specifically, this study examined the relative contribution of various risk and protective domains in relation to problem gambling behavior and examined whether youth identified as resilient (high risk exposure- high internalized protection) were as likely as those identified as vulnerable (high risk exposure-low internalized protection) to engage in excessive gambling behavior. The sample consisted of 1,273 students ages 12 to 19. The findings demonstrated that risk and protective factors each provide a unique contribution to the prediction model of gambling problems. Resilient and vulnerable youth differed significantly in their self-reported gambling severity. As well, resilient youth were not statistically distinguishable from low-risk exposure groups in terms of their gambling severity. Findings are interpreted with respect to resilience and prevention research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
Bera L.K. Ray S.K. Mukhopadhyay M. Nayak D.K. Usami N. Shiraki Y. Maiti C.K. 《Electron Device Letters, IEEE》1998,19(8):273-275
Growth of ultrathin (<100 Å) oxynitride on strained-Si using microwave N2O and NH3 plasma is reported. X-ray photoelectron spectroscopy (XPS) results indicate a nitrogen-rich layer at the strained-Si/SiO2 interface. The electrical properties of oxynitrides have been characterized using a metal-insulator-semiconductor (MIS) structure. A moderately low value of insulator charge density (6.1×1010 cm-2) has been obtained for NH3 plasma treated N2O oxide sample. Nitrided oxide shows a larger breakdown voltage and an improved charge trapping properties under Fowler-Nordheim (F-N) constant current stress 相似文献
4.
5.
In the present investigation a higher-order shear deformation theory and the conventional first-order theory are used to develop a finite element method to analyse accurately the bending and free vibration behaviour of laminated composite beams, using nine-noded isoparametric elements. The higher-order theory assumes all the displacement components, u, v and w, which contain variation up to a cubic power of z. The effects of various parameters such as fibre orientation, stacking sequence, span-to-thickness ratio and support condition on the non-dimensionalised deflections, stresses and fundamental frequencies are investigated. Cases where only the higher-order theory is likely to yield accurate results are highlighted. 相似文献
6.
Furnace grown gate oxynitride using nitric oxide (NO) 总被引:4,自引:0,他引:4
Okada Y. Tobin P.J. Reid K.G. Hegde R.I. Maiti B. Ajuria S.A. 《Electron Devices, IEEE Transactions on》1994,41(9):1608-1613
Gate oxynitride was grown in NO for the first time. This approach can provide a tight N accumulation near the Si/SiO2 interface. Much lower thermal budget is required for an NO process than for an N2O process to produce an oxynitride with useful properties. Submicron MOSFET's with NO oxynitride showed superior current drive characteristics and comparable hot carrier immunity to those with N2O oxynitride 相似文献
7.
In this paper we report the evolution of the polar cluster like behavior with the incorporation of Ti4+ ion in BaZrO3 Ceramics. Dielectric behavior of BaZrxTi(1−x)O3 (x = 1.00, 0.95, 0.90, 0.85) ceramics is studied in the temperature range from 300 to 30 K. Polar cluster like behavior becomes more prominent with the increase in content of Ti4+ ion. The dielectric relaxation is analyzed by Vogel–Fulcher relation and Arrhenius law. Frequency dependence of dielectric constant and low loss tangent of these materials can be useful for the potential applications at low temperature. 相似文献
8.
9.
Although the basal ganglia have been shown to be critical for the expression of emotion in prosody and facial expressions, it is unclear whether they are also critical for recognition of emotions. Selective pathology of parts of the basal ganglia is a hallmark of individuals with Parkinson's disease, and such patients have been examined in several studies of emotion. We examined 18 patients with Parkinson's disease (11 men, 7 women) and 13 age-, education-, gender ratio-, and IQ-matched normal controls on their ability to recognize emotions signaled by facial expressions. Parkinson's patients performed entirely normally on a quantitative task of recognizing emotional facial expressions. The findings do not support the notion that the sectors of basal ganglia that are dysfunctional in Parkinson's disease are essential for recognizing emotion in facial expressions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
S. K. Maiti 《International Journal of Fracture》1990,43(3):161-174
The approximate energy release rate for a crack which extends, or kinks, away from its original direction has been computed by finite element analysis using three different methods: stiffness derivative procedure, J integral method and crack closure integral procedure. A case study is presented to compare the computational accuracies. It suggests that a satisfactory approximation can be obtained provided that the ratio of kink length to original crack length, l(0)/a0.04, despite the interaction of the crack tip and knee stress singularities.
Résumé En utilisant trois méthodes différentes (dérivation de la raideur, intégrale J et intégrale de fermeture de la fissure), on a calculé par éléments finis la vitesse approchée de relaxation de l'energie dans le cas d'une fissure qui diverge ou qui part en arborescence par rapport à sa direction initiale.On présente une étude de cas de manière à comparer les précisions respectives obtenus dans les calculs.Cette étude suggère qu'une approximation satisfaisante peut être obtenue, pour autant que le rapport de la longueur déviée à la longueur initiale de la fissure soit inférieure ou égale à 0,04, en dépit de l'interaction entre l'extrémité de la fissure et la singularité de la contrainte.相似文献