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排序方式: 共有728条查询结果,搜索用时 15 毫秒
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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
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The preembedding double immunoreaction method was used to study interrelations of enkephalinergic and GABAergic neuronal elements in the dorsal raphe nucleus of the Wistar albino rat. The enkephalin-like neuronal elements were immunoreacted by the peroxidase-antiperoxidase method and silver-gold intensified, which showed strongly and was specific. The GABA-like immunoreactive neurons were immunoreacted by the peroxidase-antiperoxidase method only. GABA-like neural somata were postsynaptic to both the enkephalin-like immunoreactive and the non-immunoreactive axon terminals. The enkephalin-like immunoreactive axon terminals were also found to synapse GABA-like immunoreactive dendrites. The GABA-like immunoreactive neuronal elements were also found to receive synapses from other non-immunoreactive as well as GABA-like immunoreactive axon terminals. Almost all of the synapses appeared to be asymmetrical. Possible functional activity of interactions among the enkephalinergic, GABAergic, and serotonergic neuronal elements in the dorsal raphe nucleus are discussed. 相似文献
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Y Yonemura H Kimura S Fushida K Tugawa Y Nakai M Kaji L Fonseca A Yamaguchi I Miyazaki 《Canadian Metallurgical Quarterly》1993,71(8):2448-2453
BACKGROUND: Proliferative activities of tumors are thought to be prognostic features of malignant tumors, but their value as measured by proliferating cell nuclear antigen (PCNA) labeling remains unclear in gastric cancer. METHODS: PCNA labeling rates (LR) were quantified in 121 paraffin-embedded biopsy specimens from primary tumors by immunocytochemistry. RESULTS: Immunohistochemical analyses have demonstrated that PCNA presents an intense staining in the nuclei of tumor cells and mucous neck cells of gastric glands. The PCNA LR ranged from 12% to 79% (mean +/- standard deviation), and a significant correlation was found between bromodeoxyuridine labeling indices and PCNA LR: PCNA LR were closely associated with tumor size, serosal invasion, and nodal involvement. The patients with tumors with high PCNA LR (greater than 40%) were dead significantly earlier than were those with tumors with low PCNA LR: When the PCNA LR and all the clinicopathologic parameters were entered into a Cox regression model, PCNA LR emerged as an independent prognostic factor. CONCLUSION: These results indicate that PCNA LR may be a potentially useful prognostic factor for gastric cancer. 相似文献
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S Maeshima T Terada N Yoshida K Nakai T Itakura N Komai 《Canadian Metallurgical Quarterly》1997,78(6):666-669
A mechanical computerized three-dimensional scanner with a resolution of 1 micron was used to assess loss of enamel caused by orthodontic bonding and debonding. A total of 2646 measurements was performed on six human premolars. The results showed an average loss of enamel of 7.4 microns. The range was between 1 and 52 microns, which may account for discrepancies with earlier studies that measured only a few points per tooth surface. 相似文献
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A fixed-parameter, discrete-time, first-order, feedback control system is described for regulating grasp during electrical stimulation of paralyzed muscles of the hand. The stiffness of the grasp (relationship between grasp force and grasp opening) is kept constant by linearly combining force and position feedback signals. Thus, a single continuous command signal can control the size of the grasp opening prior to object acquisition and both grasp force and opening after contact. The controller achieves this change in controlled variables by scaling and summing the force and position feedback signals, rather than by a discrete switch in control strategy. Experimental tests of the control system in quadriplegic subjects show that control can be obtained over conditions ranging from unloaded position regulation to isometric force regulation, as well as in the transition between these conditions. The robustness of the control system was evaluated during force regulation with isometric loads. Step response rise time and overshoot were much more dependent on system gain than on the location of the controller zero. Responses with rise time less than two seconds and overshoot less than 30% were obtained over a gain range up to ten, indicating good robustness to muscle gain reductions such as might be caused by fatigue. 相似文献
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