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排序方式: 共有817条查询结果,搜索用时 15 毫秒
51.
Yoshikatsu Higuchi Masayuki Sugawara Koji Onishi Masatomi Sakamoto Susumu Nakayama 《Ceramics International》2010
Electrical properties of LaxM6O12+1.5x (M = Si, Ge) as an electrolyte for solid oxide fuel cell (SOFC) have been investigated. In LaxSi6O12+1.5x and LaxGe6O12+1.5x of x = 8–11, the highest conductivities were achieved at x = 9.7 (La9.7Si6O26.55) and x = 9.0 (La9.0(GeO4)6O1.5), respectively. The conductivity of La9.0(GeO4)6O1.5 was higher than that of La9.7Si6O26.55 in a temperature region higher than 700 °C, and the conductivity (2.4 × 10−3 S cm−1) of La9.7Si6O26.55 at 400 °C was higher than that (8.3 × 10−5 S cm−1) of La9.0(GeO4)6O1.5. The power densities of SOFC (H2 | Pt | electrolyte (thickness: 1 mm) | Pt | O2) using La9.0(GeO4)6O1.5 as an electrolyte were 14.3 mW cm−2 (700 °C) and 24.0 mW cm−2 (800 °C). The corresponding SOFC using La9.7Si6O26.55 was found to work even at lower temperatures of 400 and 500 °C with power densities of 0.011 and 0.12 mW cm−2. The SOFC (H2 | Ni–Sm0.2Ce0.8O1.9 | electrolyte | Ba0.5Sr0.5Co0.8Fe0.2O2.5 | air) using 0.3 mm thickness La9.7Si6O26.55 electrolyte gave the 3.4 mW cm−2 power density at 500 °C. 相似文献
52.
53.
Effects of sea surface temperature accuracy on offshore wind resource assessment using a mesoscale model 下载免费PDF全文
Susumu Shimada Teruo Ohsawa Tetsuya Kogaki Gerald Steinfeld Detlev Heinemann 《风能》2015,18(10):1839-1854
Offshore wind simulations were performed with the Weather Research and Forecasting (WRF) model driven by three different sea surface temperature (SST) datasets for Japanese coastal waters to investigate the effect of the SST accuracies on offshore wind simulations. First, the National Centers for Environmental Prediction Final analysis (FNL) (1° × 1° grid resolution) and the Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA) (0.05° × 0.05° grid resolution) datasets were compared with in situ measurements. The results show a decrease in accuracy of these datasets toward the coast from the open ocean. Aiming at an improved accuracy of SST data, we developed a new high‐resolution SST dataset (0.02° × 0.02° grid resolution). The new dataset referred to as MOSST is based on the Moderate Resolution Imaging Spectroradiometer (MODIS) product, provided by the Japan Aerospace Exploration Agency (JAXA). MOSST was confirmed to be more accurate than FNL and OSTIA for the coastal waters. Then, WRF simulations were carried out for 1 year with a 2 km grid resolution and by using the FNL, OSTIA and MOSST datasets. The use of the OSTIA dataset for a WRF simulation was found to improve the accuracy when compared with the FNL dataset, and further improvement was obtained when the MOSST dataset was applied. The sensitivity of wind speed and wind energy density to SST is also discussed. We conclude that the use of an accurate SST is a key factor not only for realistic offshore wind simulations near the surface but also for accurate wind resource assessments at the hub height of wind turbines. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
54.
A novel dynamic survivable routing in WDM optical networks with/without sparse wavelength conversion
Vinh Trong Le Xiaohong Jiang Son Hong Ngo Susumu Horiguchi Yasushi Inoguchi 《Optical Switching and Networking》2006,3(3-4):173-190
In this paper, we study the dynamic survivable routing problem, both in optical networks without wavelength conversion and in optical networks with sparse wavelength conversion, and propose a novel hybrid algorithm for it based on the combination of mobile agents technique and genetic algorithms (GA). By keeping a suitable number of mobile agents in the network to cooperatively explore the network states and continuously report cycles (that are formed by two disjoint-link routes) into the routing tables, our new hybrid algorithm can promptly determine the first population of cycles for a new request based on the routing table of its source node, without the time consuming process associated with current GA-based lightpath protection schemes. We further improve the performance of our algorithm by introducing a more advanced fitness function that is suitable for both the above networks. Extensive simulation studies on the ns-2 network simulator show that our hybrid algorithm achieves a significantly lower blocking probability than the conventional survivable routing algorithms for all the cases we studied. 相似文献
55.
Bis-(monoacylglyceryl) phosphate and acyl phosphatidylglycerol were isolated from the liver of two patients with lipidosis
induced by 4,4′-diethylaminoethoxyhexesterol. Identification was based upon the results of alkaline hydrolysis, acetolysis,
IR spectrometry, and upon the determination of molar ratio of phosphorus-glycerol-ester. The contents of the bis-(monoacylglyceryl)
phosphate were 10 and 16% total phospholipid phosphorus in them. The bis-(monoacylglyceryl) phosphate contained mainly docosahexaenoic
(42%), oleic (29%), and linoleic acid (14%) and had the hemolytic activity of ca. one-eighth lysolecithin from egg yolk. Acidic
lipids from the liver also were found to contain a lipid which is less polar than bis-(monoacylglyceryl) phosphate. The results
of lipid analysis showed that the lipid possessed the structure of an acyl phosphatidylglycerol, and its content was ca. 2%
total phospholipid phosphorus. Accumulation of 4,4′-diethylaminoethoxyhexesterol and its derivatives was found in clinical
cases by thin layer chromatography and IR spectrometry. This fact suggested that human liver has an ability to metabolize
the drug. 相似文献
56.
Microwave dielectric properties and crystal structures of Mg0.7Al2.2O4 and Mg0.4Al2.4O4 ceramics with defect structures 下载免费PDF全文
Susumu Takahashi Akinori Kan Hirotaka Ogawa 《Journal of the American Ceramic Society》2017,100(8):3497-3504
Mg0.7Al2.2O4 and Mg0.4Al2.4O4 ceramics with cation vacancies were synthesized using the molten salt method, and the relationships between the microwave dielectric properties and crystal structures of these materials were investigated. The 27Al NMR spectra of these ceramics indicate that the preferential occupation of tetrahedral sites by Al3+ cations was enhanced by the introduction of cation vacancies. The λ values of Mg0.7Al2.2O4 and Mg0.4Al2.4O4 ceramics fired at 1600°C, which correspond to the fraction of Al3+ cations in tetrahedral sites, were 0.37 and 0.60, respectively. Crystal structure refinements using the Rietveld method suggest that cation vacancies are preferentially located at octahedral sites in both ceramics. The εr and Q·f values of a Mg0.7Al2.2O4 ceramic fired at 1600°C were 7.7 and 201 111 GHz, respectively, while those of a Mg0.4Al2.4O4 ceramic fired at 1600°C were 7.5 and 232 301 GHz, respectively. These data demonstrate that the preferential occupation of tetrahedral sites by Al3+ cations following the introduction of cation vacancies enhances the Q·f value. 相似文献
57.
Yasuo Y. Suzuki Shin-ichi Saito Susumu Kurihara 《Journal of Low Temperature Physics》1998,113(5-6):897-902
We investigated the ground state of the infinite dimensional Hubbard model for both attractive and repulsive interactions by applying Gutzwiller type variational wave functions. Our variational wave functions have lower energies than the simple BCS wave function for the attractive case, and lower energies than the Brinkman-Rice state for the repulsive case. We found that the system has several phases depending on the density of electrons and the interaction strength. Investigated phases include antiferromagnetic, Fermi liquid, superconducting, charge density wave, and supersolid phases. The last one is a coexistence phase of superconducting and charge density wave states. 相似文献
58.
An ultrasonic treatment system, using a TiO2 photocatalyst, was used to disinfect Legionella pneumophila. A kinetic study of the process indicates that TiO2 significantly improves the disinfection process. The concentrations of viable cells were reduced to 6% of the initial concentrations in the presence of 0.2 g/ml TiO2 after a 30 min of treatment period, while only an 18% reduction was observed in the absence of TiO2. The potency of the disinfection could be enhanced, to some extent, by increasing the amount of TiO2 used. Cell concentrations were decreased by an order of 3 within 30 min of treatment in the presence of 1.0 g/ml TiO2. The disinfection power in the presence of TiO2 versus Al2O3 was also compared and the findings showed that TiO2 induced a higher cell killing. No significant effect of initial cell concentration on the disinfection was found in the range of 102-107 CFU/ml after a 30 min of treatment period. The mechanism of cell killing was investigated by examining the effects of OH radical scavengers such as ascorbic acid, histidine and glutathione. The disinfection power was reduced in samples that contained these radical scavengers, thus indicating the importance of OH radicals. 相似文献
59.
A three-dimensional compaction device has been developed to carry out compaction of a ceramic powder. The details of the device, which provides compaction with various stress ratios, are described. A densification criterion for the powder is proposed; this is similar to that for the case for metal powders, but the role of the hydrostatic stress component appears to be different. Stress-strain rate relations are then derived using the concept of plastic potential; experimental results show that the normality of the strain rate vector to the surface which corresponds to the criterion almost holds. 相似文献
60.
Kusaka T Ueno M Miki T Kanenishi K Nagai Y Huang CL Okamoto Y Ogawa T Onodera M Itoh S Akiguchi I Sakamoto H 《Microscopy research and technique》2007,70(7):648-655
We investigated whether beta-amyloid (Abeta)-like immunoreactivity was seen in the brains of newborn piglets. The immunoreactivity for Abeta(1-42) and Abeta(1-40) proteins, but not Abeta precursor protein, was present in CD68-positive perivascular cells of the hippocampus and in parts of the meninges. It was colocalized with immunoreactivity for receptor for advanced glycation end product and tumor necrosis factor-alpha. The protein with a molecular mass of 27 kDa, which was recognized by the Abeta antibodies, was identified as triosephosphate isomerase (TPI) with sequence homology to Abeta peptides by N-terminal amino acid sequencing, mass fingerprint analysis using matrix-associated laser desorption/ionization mass spectrometry, and Western blotting. Western blotting assay also revealed that detectable expression of Abeta proteins were not seen in the piglet brains. These findings indicate that TPI with sequence homology to Abeta peptides accumulates in perivascular cells of the microglia/macrophage lineage located around arterial vessels of the newborn piglet hippocampus. 相似文献