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101.
M. Cai H. Morioka P.K. Kaiser Y. Tasaka H. Kurose M. Minami T. Maejima 《International Journal of Rock Mechanics and Mining Sciences》2007,44(4):538-549
Most back-analyses in geotechnical engineering are based on methods that utilize field displacement monitoring data. In the present study, a novel method is developed to back-calculate rock mass strength parameters from AE (acoustic emission) monitoring data in combination with FEM stress analysis. The method is based on the important concept of generalized AE initiation threshold of rock masses, established from comprehensive data analysis of laboratory test and underground monitoring programs using AE and microseismic (MS) techniques. An easy-to-use Wizard is developed in Microsoft Excel™ to assist site engineers to perform the back-analysis. The efficient solver in Excel is utilized to reach the optimization solution of an objective function with constraints. The Wizard allows the user to complete the analysis process in an interactive fashion. One example is given to demonstrate the back-analysis process using AE monitoring data recorded from a cavern site. The rock mass strength parameters identified from this approach compare well with field test data, suggesting that the tool can be used effectively to back-calculate rock mass strength parameters from AE monitoring data. 相似文献
102.
Fine Patterning and Characterization of Gel Films Derived from Methyltriethoxysilane and Tetraethoxysilane 总被引:1,自引:0,他引:1
Atsunori Matsuda Yoshihiro Matsuno Masahiro Tatsumisago Tsutomu Minami 《Journal of the American Ceramic Society》1998,81(11):2849-2852
Pregrooves of 1.6 µm pitch for optical data storage have been embossed successfully by pressing a stamper against x CH3 Si(OC2 H5 )3 (100 - x )Si(OC2 H5 )4 -derived gel films (60 ≤ x ≤ 100 mol%) on glass-disk substrates of 130 mm diameter. When x is <40 mol%, the resultant films are too hard to emboss patterns uniformly. The shrinkage of the patterns is ∼4% for all the films when 60 lessthan equal to x lessthan equal to 100 mol%, even after heat treatment at 350°C, so that the nearly net negative shape of the stamper is preserved. The methyl groups in the films decompose at temperatures from 500° to 600°C. 相似文献
103.
O Matsushita CM Jung S Katayama J Minami Y Takahashi A Okabe 《Canadian Metallurgical Quarterly》1999,181(3):923-933
Clostridium histolyticum collagenase contains a number of different active components. Previously we have shown that colH encodes a 116-kDa collagenase (ColH) and a 98-kDa gelatinase. We purified a different 116-kDa collagenase (ColG) from the culture supernatant and sequenced its gene (colG). We also identified four other gelatinases (105, 82, 78, and 67 kDa) and determined their N-terminal amino acid sequences, all of which coincided with that of either ColG or ColH. Hybridization experiments showed that each gene is present in a single copy and each gene is transcribed into a single mRNA. These results suggest that all the gelatinases are produced from the respective full-length collagenase by the proteolytic removal of C-terminal fragments. The substrate specificities of the enzymes suggest that colG and colH encode class I and class II enzymes, respectively. Analysis of their DNA locations by pulsed-field gel electrophoresis and nucleotide sequencing of their surrounding regions revealed that the two genes are located in different sites on the chromosome. C. histolyticum colG is more similar to C. perfringens colA than to colH in terms of domain structure. Both colG and colA have a homologous gene, mscL, at their 3' ends. These results suggest that gene duplication and segment duplication have occurred in an ancestor cell common to C. histolyticum and C. perfringens and that further divergence of the parent gene produced colG and colA. 相似文献
104.
Toshiyuki Nagata Kentaro Minami Masatatsu Yamamoto Tsubasa Hiraki Masashi Idogawa Katsumi Fujimoto Shun Kageyama Kazuhiro Tabata Kohichi Kawahara Kazuhiro Ueda Ryuji Ikeda Yukio Kato Masaaki Komatsu Akihide Tanimoto Tatsuhiko Furukawa Masami Sato 《International journal of molecular sciences》2021,22(21)
105.
Effect of Ga2O3 on Sintering and Phase Stability of Sc2O3‐Doped Tetragonal Zirconia Prepared via Aqueous Solution Route 下载免费PDF全文
Masanori Hirano Hideo Kojima Hideaki Minami 《Journal of the American Ceramic Society》2015,98(1):44-49
The effects of the presence of Ga2O3 on low‐temperature sintering and the phase stability of 4, 5, and 6 mol% Sc2O3‐doped tetragonal zirconia ceramics (4ScSZ, 5ScSZ, and 6ScSZ, respectively) were investigated. A series of zirconia sintered bodies with compositions (ZrO2)0.99?x(Sc2O3)x(Ga2O3)0.01, x = 0.04, 0.05, and 0.06 was fabricated by sintering at 1000°C to 1500°C for 1 h using fine powders that were prepared via the combination of homogeneous precipitation method and hydrolysis technique using monoclinic zirconia sols synthesized through the forced hydrolysis of an aqueous solution of zirconium oxychloride at 100°C for 168 h. The presence of 1 mol% Ga2O3 was effective in reducing sintering temperature necessary to fabricate dense bodies and enabled to obtain dense sintered bodies via sintering at 1100°C for 1 h. The phase stability, that is, low‐temperature degradation behavior of the resultant zirconia ceramics was determined under hydrothermal condition. The zirconia ceramics codoped with 1 mol% Ga2O3 and 6 mol% Sc2O3 (1Ga6ScZ) fabricated via sintering at 1300°C for 1 h showed high phase stability without the appearance of monoclinic zirconia phase, that is the tetragonal‐to‐monoclinic phase transformation was not observed in the 1Ga6ScZ after treatment under hydrothermal condition at 150°C for 30 h. 相似文献
106.
Hideyuki Yamamoto Toshiya Minejima Ichiro Sumitani Soji Kojima Takato Fukano Takamitsu Tada 《Electrical Engineering in Japan》1999,127(1):1-10
Grounding wires and enclosed ZnO elements have been incorporated generally in 6.6‐kV distribution systems by TEPCO for the reduction of lightning overvoltages. At present, the reliability to lightning surges is tolerably good. However, the facility of grounding wires is not inexpensive and its maintenance is hard due to corrosion and disconnection in some areas. A typical model simulating TEPCO field adopting enclosed ZnO elements has been developed and we have evaluated relative failure risks systematically according to conditions with and without grounding wires against lightning overvoltages. Two kinds of failures discussed in the paper are the flashover of insulation and the overduty of ZnO elements, and two kinds of induced and direct lightning overvoltages are studied in flashover. The greatest problem with no grounding wire is the increase of ZnO elements' duty, but it was demonstrated that a short partial grounding wire around ZnO elements or the selection of heavier ZnO elements provides a solution. The main objectives of this study are to clarify the relative failure risks systematically according to realistic field conditions, the risk of small stroke currents having long duration to ZnO elements' duty, and countermeasures against ZnO elements' overduty. © 1999 Scripta Technica, Electr Eng Jpn, 127(1): 1–10, 1999 相似文献
107.
Nylon-6 substrates were coated with SiO2-RSiO3/2 (R = methyl, vinyl, phenyl) thin films by the sol-gel method, and their water permeability was evaluated Tetraethoxysilane (TEOS) and trifunctional alkoxides such as methyltriethoxysilane (MTES), vinyltriethoxysilane (VTES), and phenyltriethoxysilane (PhTES) were used as starting materials. Water permeability coefficients of the nylon-6 substrates coated with these SiO2-RSiO3/2 thin films were increased with an increase in the content of these trialkoxysilanes in the films. The water permeability coefficients of these coated nylon-6 substrates were smaller in the order of the systems TEOS-PhTES < TEOS-VTES < TEOS-MTES in the relatively low content of the trialkoxysilanes. © 1996 John Wiley & Sons, Inc. 相似文献
108.
Parallel BDD-based monolithic algorithms for acoustic fluid-structure interaction problems are developed. In a previous study, two schemes, NN-I + CGC-FULL and NN-I + CGC-DIAG, have been proven to be efficient among several BDD-type schemes for one processor. Thus, the parallelization of these schemes is discussed in the present study. These BDD-type schemes consist of the operations of the Schur complement matrix-vector (Sv) product, Neumann-Neumann (NN) preconditioning, and the coarse problem. In the present study, the Sv product and NN preconditioning are parallelized for both schemes, and the parallel implementation of the solid and fluid parts of the coarse problem is considered for NN-I + CGC-DIAG. The results of numerical experiments indicate that both schemes exhibit performances that are almost as good as those of single solid and fluid analyses in the Sv product and NN preconditioning. Moreover, NN-I + CGC-DIAG appears to become more efficient as the problem size becomes large due to the parallel calculation of the coarse problem. 相似文献
109.
Lu J Minami K Takami S Shibata M Kaneko Y Adschiri T 《ACS applied materials & interfaces》2012,4(1):351-354
ITO nanoparticles were synthesized hydrothermally and surface modified in supercritical water using a continuous flow reaction system. The organic modification of the nanoparticles converted the surface from hydrophilic to hydrophobic, making the modified nanoparticles easily dispersible in organic solvent. The addition of a surface modifier into the reaction system impacted the crystal growth and particle size as well as dispersion. The particle size was 18 nm. Highly crystalline cubic ITO with a narrow particle size distribution was obtained. The advantages of short reaction time and the use of a continuous reaction system make this method suitable for industrial scale synthesis. 相似文献
110.
Gentoku Kido Mikihiro Takasaki Kimitaka Minami Hisashi Tanaka Hiroshi Ogawa Tohru Kawamoto 《Journal of Nuclear Science and Technology》2017,54(11):1157-1162
Ash-washing technology is a crucially important technology for removing radioactive Cs from contaminated ash. For that technology, Cs+ removal from the ash-washing solution by the adsorbent is necessary. This study was conducted to establish rapid preparation of appropriate adsorption columns for Cs+ uptake. A one-site model was not used for analysis because the model cannot accommodate sites with different adsorption speed. Results demonstrated that the adsorption behavior of the column filled with the granules of potassium copper hexacyanoferrate was well reproduced by a two-site adsorption model with parameters chosen through analysis of batch adsorption test results. 相似文献