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排序方式: 共有263条查询结果,搜索用时 15 毫秒
51.
Chen D Gao L Yasumori A Kuroda K Sugahara Y 《Small (Weinheim an der Bergstrasse, Germany)》2008,4(10):1813-1822
Two-dimensional monoclinic WO(3) nanoplates with high specific surface areas are synthesized through a novel conversion process using tungstate-based inorganic-organic hybrid micro/nanobelts as precursors. The process developed involves a topochemical transformation of tungstate-based inorganic-organic hybrid belts into WO(3) nanoplates via an intermediate product of H(2)WO(4) nanoplates, utilizing the similarity of the W-O octahedral layers in both H(2)WO(4) and WO(3). The as-obtained WO(3) nanoplates show a single-crystalline nanostructure with the smallest side along the [001] direction. The WO(3) nanoplates are 200-500 nm x 200-500 nm x 10-30 nm in size, and their specific surface areas are up to 180 m(2) g(-1). Photocatalytic measurements of visible-light-driven oxidation of water for O(2) generation in the presence of Ag(+) ions indicate that the activity of the as-obtained WO(3) nanoplates is one order of magnitude higher than that of commercially available WO(3) powders. 相似文献
52.
Y Yamane R Tohno-oka S Yamada S Furuya K Shiokawa Y Hirabayashi H Sugino K Sugahara 《Canadian Metallurgical Quarterly》1998,273(13):7375-7381
Enzymatic elimination of heparan sulfate (HS) causes abnormal mesodermal and neural formation in Xenopus embryos, and HS plays an indispensable role in establishing the embryogenesis and tissue morphogenesis during early Xenopus development (Furuya, S., Sera, M., Tohno-oka, R., Sugahara, K., Shiokawa, K., and Hirabayashi, Y. (1995) Dev. Growth Differ. 37, 337-346). In this study, HS was purified from Xenopus embryos to investigate its disaccharide composition and binding ability to basic fibroblast growth factor (bFGF) and follistatin (FS), the latter being provided in two isoforms with core sequences of 315 and 288 amino acids (designated FS-315 and FS-288) originating from alternative mRNA splicing. Disaccharide composition analysis of the purified Xenopus HS showed the preponderance of a disulfated disaccharide unit with uronic acid 2-O-sulfate and glucosamine 2-N-sulfate, which has been implicated in the interactions with bFGF. Specific binding of the HS to bFGF and FS-288, the COOH-terminal truncated form, was observed in the filter binding assay, whereas HS did not bind to FS-315, indicating that the acidic Glu-rich domain of FS-315 precluded the binding. The binding of the HS to bFGF or FS-288 was markedly inhibited by heparin (HP) and various HS preparations, but not by chondroitin sulfate, supporting the binding specificity of HS. The binding specificity was further investigated using FS-288 and bovine intestinal [3H]HS. Competitive inhibition assays of the HS binding to FS-288 using size-defined HP oligosaccharides revealed that the minimum size required for significant inhibition was a dodecasaccharide, which is larger than the pentasaccharide required for bFGF binding. The binding affinity of FS to HS increased in the presence of activin, a growth/differentiation factor, which could be inactivated by direct binding to FS. These results, taken together, indicate that the structural requirement for binding of HS to bFGF and FS is different. HS may undergo dynamic changes in its structure during early Xenopus embryogenesis in response to the temporal and spatial expression of various growth/differentiation factors. 相似文献
53.
T Hamasaki Y Fujikawa M Sugahara H Ozaki T Yano R Imada G Prasai Y Tainaka W Nakamura F Haruki 《Water science and technology》2004,50(5):369-372
Presented in this paper are the results of a series of column experiments and a pilot scale test conducted to develop the treatment system of freshwater and wastewater by their percolation through soil and the other materials at the rate of a few metres per day. Materials that had high ability to sorb fulvic acid (FA hereafter) and phosphate ion were selected based on the results of the batch sorption tests and were processed into beads before subjecting them to the column test. The results of the column experiment suggested that the reagents added to increase the strength of the beads reduced the sorption of FA, thus causing the early breakthrough of the FA injected into the column. Less effect from the bead processing was observed for the removal of phosphate ion. Pilot scale test showed that the removal of particulate fraction of phosphorus differed among the materials used. The bead processing technique that can ensure the high water permeability while maintaining the sorption capacity of the material was required for further development of the treatment system. 相似文献
54.
A new cystathionine metabolite has been identified in the urine of a patient with cystathioninuria using liquid chromatography-mass spectrometry with an atmospheric pressure chemical ionization interface system (LC/APCI-MS). By this method a very intense quasi-molecular ion was observed as a base peak of synthetic N-acetyl-S-(3-oxo-3-carboxy-n-propyl)cysteine (NAc-OCPC). The quasimolecular ion [M + H]+ of NAc-OCPC observed in the urine of a patient with cystathioninuria was the same as that of the authentic compound (m/z 264). The retention time and Rf value on paper chromatography of the synthetic compound were the same as those of the urinary compound from the patient with cystathioninuria. From these results, this new cystathionine metabolite was identified as N-acetyl-S-(3-oxo-3-carboxy-n-propyl)cysteine. 相似文献
55.
56.
Tsutomu Fujita Shoji Watanabe Kenji Miharu Kazunori Itoh Kotoji Sugahara 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(2):57-62
Various 2-(2′-hydroxy-4′-methyl-1′-cyclohexylidene) carboxylic acid lactones were synthesised in good yield from carboxylic acids and 4-methylcyclohexanone. For example, mintlactone ( VI ) and isomintlactone ( VII ) were prepared from 2-(1′- hydroxy-4′-methylcyclohexan-1′-yl) propanoic acid ( III ) which was obtained by reaction of propanoic acid ( I ) with 4-methylcyclohexanone ( II ) using lithium naphthalenide in the presence of diethylamine. Compound ( VI ) could be separated from compound ( VII ) by silica gel column chromatography. Several new 2-(2′- hydroxy-4′-methyl-1′-cyclohexylidene) carboxylic acid lactones which may be used as perfumery materials, were obtained in good yield by this method. 相似文献
57.
H Mori M Yamao H Nakazawa Y Sugahara N Shirai F Matsubara M Sumida T Imamura 《Canadian Metallurgical Quarterly》1995,13(9):1005-1007
We introduced a firefly luciferase gene, expressed under control of Drosophila heat shock protein gene promoter, into Autographa californica nuclear polyhedrosis virus (AcNPV). When the 5th instar larvae of the silkworm, Bombyx mori, were inoculated with the recombinant virus, luciferase activities were detected in the virus-infected larvae and pupae, and in the newly hatched larvae of the next generation. PCR amplification and Southern blot hybridization analysis demonstrated that the luciferase gene was transmitted through at least the F2 generation. In addition, the V-cathepsin gene, encoding a cysteine protease of AcNPV, was also detected in the DNA of all individuals of the F2 generation. These results show that AcNPV can be utilized as vector for the transovarian transmission of foreign genes in the silkworm. 相似文献
58.
M Furuse M Matsumoto R Mori K Sugahara K Kano S Hasegawa 《Canadian Metallurgical Quarterly》1997,764(1-2):289-292
Recently, we have reported that central administration of glucagon-like peptide-1 (GLP-1) strongly decreased food intake of chicks. The aim of the present study was to elucidate whether suppressed food intake by central injection of GLP-1 would be modified by an appetite stimulant such as fasting and neuropeptide Y (NPY). Birds (2 days old) were starved for 3 or 6 h and then GLP-1 (0.03 microg/10 microl) or saline was injected by the intracerebroventricular (i.c.v.) route. Birds starved for 6 h ate significantly more food than those starved for 3 h, while irrespective of the time for fasting GLP-1 strongly inhibited food intake as rapidly as 10 min after i.c.v injection. The suppressive effect on food intake continued until 4 h after injection. Central administration of NPY (2.5 microg/10 microl) greatly enhanced food intake, but co-injection of GLP-1 (0.01, 0.02 or 0.03 microg/10 microl) decreased food intake in a dose-dependent fashion. Under GLP-1 (0.03 microg/10 microl) treatment, whether NPY modifies food intake of chicks in a dose-dependent manner was investigated by co-injection of graded levels of NPY (0.4, 1.0 and 2.5 microg/10 microl). GLP-1 completely inhibited the effect of NPY on food intake without a dose response. These results suggest that central GLP-1 may interact with NPY and may be the most potent inhibitor of food intake in the chicken. 相似文献
59.
Close visual bridge inspection using a UAV with a passive rotating spherical shell 总被引:1,自引:0,他引:1
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Carl John O. Salaan Yoshito Okada Shoma Mizutani Takuma Ishii Keishi Koura Kazunori Ohno Satoshi Tadokoro 《野外机器人技术杂志》2018,35(6):850-867
Today, robots are expected to be used for the inspection of infrastructures such as bridges. One important task in bridge inspection is to acquire clear images of its various parts for further damage evaluation. However, this task has not yet been completely realized because of the complexity of bridge structures. For this situation, a UAV with a passive rotating spherical shell (PRSS) that can easily maneuver while protecting itself is introduced. In this paper, we explain the development of the PRSS unmanned aerial vehicle (UAV) based on the design strategy. We then analyze its performance through simulated bridge inspection. Finally, we discuss the results of actual bridge experiments. The spherical shell has a size ( 0.95 m) and structure (fullerene) that is well‐suited for bridge inspection applications. It can also handle an impact equivalent to 2 m/s, which is more than the UAV's maximum flight speed. Test flight experiment also validated the characteristic of PRSS that shows a stable flight during disturbances. The image test also shows that the visual system can provide a full overhead view of the bridge. Likewise, it can detect a 0.1‐mm wide line that replicates the damage (e.g., a crack) from a position 0.5 m away and while the camera moves at 0.3 m/s. These characteristics have yielded a system that can acquire inspection images from critical parts of the bridge. An evaluation by third parties confirmed the effectiveness of the system. Further, the system satisfies the mandatory requirements of the Next Generation Robots for Social Infrastructure (NGRSI) program. 相似文献
60.
Hideo Sugahara Kenta Arai Naoki Kamata Masakazu Kato 《Electrical Engineering in Japan》2015,190(2):41-56
This paper proposes optimal total planning for incinerator plants (IPs) in a typical urban area, which includes a method of determining the number of plants and the capacities of the IPs. Burnable municipal refuse is disposed of sanitarily by high‐temperature incineration at the IPs. At the same time, power generation from waste (PGW) is being performed at many IPs to recover energy. At present, the amount of energy generated by PGW is greater than that of wind power or photovoltaic power generation. However, PGW has a limited generation efficiency and low generation output due to the smaller capacity of IPs. To overcome the above weakness, highly efficient PGW is necessary with total integration and scaling up of IPs. Regarding total integration and scaling up, operation in larger areas is favorable from the point of view of refuse volume and collection. In the planning stage, both the cost of IPs and refuse collection, which is important for refuse disposal, should be taken into account comprehensively. Optimal total planing for IPs can be performed in two stages. First, the disposal capacity Gk of an IP versus the number of plants K is decided by constraints. Gk is about the same for all K because of maintenance and refuse collection, and is greater than 300 tons per day in steps of 100 tons per day. Gk should be decided not only by refuse volume but also by cessation of operation at plants due to maintenance or faults. Second, the cost of each value of K is calculated based on the construction and operating costs of the IPs, income from selling the energy of PGW, and refuse collection costs. Therefore, the value of K with the minimum cost is selected as the optimal number of IPs. A numerical simulation of an area with a population of 3 million indicates that the optimal plant number is 4. At present there are eight or nine IPs in cities of 3 million people. The above cost reduction effect will be about 15% from the present value. Considering the situation of aging IPs, a decreasing trend in refuse volume, and the stringent financial conditions of local governments, the proposed method is very effective and realistic. 相似文献