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131.
三维数值模拟技术在深部大型发电站厂房信息化施工中的应用 总被引:4,自引:5,他引:4
提出一种可以综合考虑围岩节理分布特性、爆破施工损伤以及施工过程的新三维快速数值仿真模拟技术,并将其成功地应用于日本宫崎县120×10~4kW蓄能水力发电工程大型地下厂房的信息化施工中。依据多种测试手段,对开挖后围岩的稳定性和变形进行实时监测,并对数值模型进行三维反演分析和修正,比较准确地预测了围岩的动态变化过程,并对支护结构设计的可靠性和合理性进行了详细的论证。 相似文献
132.
Hiromichi Aono Takaaki Nishida Masato Kurihara Masatomi Sakamoto Yoshihiko Sadaoka 《Ceramics International》2012,38(3):2333-2338
New heteronuclear (NH4)REIII[FeII(CN)6]·nH2O complexes (RE = La, Ce, Pr, Nd, Sm, Gd, Dy, Y, Er, Lu) were synthesized and their thermal decomposition products were investigated. The crystal structure of (NH4)RE[FeII(CN)6]·nH2O would be a hexagonal unit cell (space group: P63/m), which was the same as that of La[FeIII(CN)6]·5H2O. The hydration number n = 4 was estimated by TG results for all the RE complexes. The lattice constants depended on the ionic radius of the RE3+ ion for the heteronuclear complexes. The single phase of the perovskite type materials was directly obtained by decomposition of the heteronuclear complexes for RE = La, Pr, Nd, Sm, and Gd. A mixture of CeO2 and Fe2O3 was formed for RE = Ce because of its oxidation to Ce4+. In the case of RE = Dy, Y, Er, and Lu complexes, the perovskite type materials formed at higher temperature via. mixed oxides such as RE2O3 and RE4Fe5O13 due to the small RE3+ ionic radius. 相似文献
133.
A method for profiling arachidonic acid metabolites by radio gas chromatography (GC) is described. The incubation mixture
of rabbit platelets with [14C]arachidonic acid was purified on a Sep-Pak C18 cartridge and derivatized with diazomethane,O-methylhydroxylamine and dimethylisopropylsilylimidazole. The recovery of total14C-radioactivity was 93.1±7.2%. Loss of radioactivity during derivatization was negligible. Baseline separations for [14C]arachidonic acid and its metabolites were obtained in a single run within 45 min by GC using a synchronized accumulating
radioisotope detector (GC/SARD). The recovery of radioactivity from the GC column was virtually 100%. The chemical structures
of the metabolites were confirmed by GC/mass spectrometry; peaks of arachidonic acid metabolites were assigned by comparison
of the methylene unit values with those of radioactive peaks in GC/SARD analyses. The intra-assay coefficients of variation
in GC/SARD analyses were less than 10%. The method was used to map the profile of arachidonic acid metabolites formed by rabbit
platelets in the presence of indomethacin, baicalein or glutathione. 相似文献
134.
Since the present hierarchical power grid structure and AC interface are mature and rigid, a new electric power system architecture is proposed here to save the earth by making use of renewable energy sources. The architecture consists of a new concept and a historical technology, that is, a network of many “electric clusters” with a DC interface. The cluster includes dispersed electric power generators, electric appliances, electric storage, and “electric power routers.” The router is equipment to resourcefully route electrical energy between neighboring clusters and to manage electrical energy in the cluster. The transfers of electrical energy (between clusters and within clusters) and the generation of electricity from renewal energy sources (such as sunlight, wind, tides, and biogas) are intermittent and have very wide dynamic ranges, so that the interface must make use of DC. When we achieve an energy society with this architecture, we will be able to reduce energy consumption, greenhouse gas emissions, and materials use. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(1): 18–25, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20039 相似文献
135.
S. M. Najib S. Yusoh Shingo Yamashita Naomi Kokubo Yoshihiko Nomura 《Artificial Life and Robotics》2009,13(2):442-446
This study aims to improve human jumping capabilities from an engineering perspective by proposing a supportive device, as
in a robot suit. The robot expresses a time-oriented optimal torque pattern, which is the most efficient jumping motion and
timing, of each joint that can jump the highest using a motor. Then humans learn the most efficient jumping motion. To actualize
the most efficient jumping motion, we observe human jumping motions and analytically calculate the most efficient torque patterns
based on them.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
136.
Akihiko Hirata Yoshihiko Hirotsu Satoru Kuboya T.G. Nieh 《Journal of Alloys and Compounds》2009,483(1-2):64
Local structural fluctuation in relation to the medium range order (MRO) in a Pd–Ni–P bulk metallic glass was examined using nanobeam electron diffraction (NBED) technique. We found diffraction spots with strong intensities in the NBED patterns taken from any observation sites in the specimen. This indicates a presence of MRO regions densely formed in the specimen. The diffraction spots in NBED were normally dispersed around positions corresponding to the first halo-diffraction ring in selected area diffraction. A low-temperature annealing led to form a nanocrystalline microstructure consisting of unidentified phosphides. In the course of annealing, the MRO structures deduced from the NBED patterns have no structural similarity to the phosphides found in the primary crystallization stage. The MRO structure changes into a similar structure with the primary crystals just before the crystallization. A discussion is made for the MRO structure and its relation to the glass stability and also to the phosphide nucleation in the primary crystallization. 相似文献
137.
Matsui Y Matsushita T Sakuma S Gojo T Mamiya T Suzuoki H Inoue T 《Environmental science & technology》2003,37(22):5175-5180
Inorganic aluminum salts, such as aluminum sulfate, are coagulants that cause small particles, such as bacteria and viruses as well as inorganic particles, to destabilize and combine into larger aggregates. In this investigation, batch coagulation treatments of water samples spiked with Qbeta, MS2, T4, and P1 viruses were conducted with four different aluminum coagulants. The total infectious virus concentration in the suspension of floc particles that eventually formed by dosing with coagulant was measured after the floc particles were dissolved by raising the pH with an alkaline beef extract solution. The virus concentrations were extremely reduced after the water samples were dosed with aluminum coagulants. Viruses mixed with and adsorbed onto preformed aluminum hydroxide floc were, however, completely recovered after the floc dissolution. These results indicated that the aluminum coagulation process inactivates viruses. Virucidal activity was most prominent with the prehydrolyzed aluminum salt coagulant, polyaluminum chloride (PACl). Virucidal activity was lower in river water than in ultrapure water--natural organic matter in the river water depressed the virucidal activity. Mechanisms and kinetics of the virus inactivation were discussed. Our results suggest that intermediate polymers formed during hydrolysis of the aluminum coagulants sorbed strongly to viruses, either rendering them inactive or preventing infectivity. 相似文献
138.
Phase diagram of high-T
c vortex states in
with point defects is investigated by large-scale Monte Carlo simulations. We find that the first-order boundary between the vortex slush and vortex liquid phases terminates at a critical point, and that there is a step of the specific heat above the critical point as reported experimentally. As the system size increases, this step becomes sharper but smaller, and is associated with a crossover rather than a thermodynamic phase transition. 相似文献
139.
Tsuyoshi Tamegai Zhixiang Shi Aswini Kumar Pradhan Hitomi Nakamura Ajay Kumar Ghosh Masashi Tokunaga Yoshihiko Takano Kazumasa Togano Hijiri Kito Hideo Ihara 《Journal of Low Temperature Physics》2003,131(5-6):1153-1157
Anisotropic superconducting properties of inter-metallic compounds MgB2, Y2PdGe3, and CaAlSi with AlB2 structure are studied by detailed angular dependent transport measurements. MgB2 and CaAlSi shows appreciable anisotropy of the upper critical field, H
c2, with mass anisotropy parameter =3 and 2, respectively, while Y2PdGe3 is almost isotropic. In-plane anisotropy of H
c2 in these hexagonal superconductors is very small, consistent with the prediction based on GL theory. 相似文献
140.
In order to minimize the stiction force caused by contact of the extremely smooth surfaces of head sliders and disks in hard disk drives, texture is usually applied on the disk surface. For future contact/near-contact recording, the stiction-induced high friction between slider and disk will become a problem. Texture on the slider/disk interface will still be an expected method to reduce friction. Recently, it was suggested to texture the slider surface. A protective coating is usually required on the textured slider surface to reduce wear of the texture. The results showed that texture on the slider surface was effective in reducing the friction between head sliders and disks. On the other hand, the texture and coating on the slider surface increase the spacing between the read/write element and the magnetic layer of the disk. The necessary and effective texture height and coating thickness are still not clear. In the present research, island-type textures with different heights (3–18 mn) were formed on slider surfaces by ion-beam etching. Amorphous carbon nitride (a-CNx) coatings of different thicknesses (0–50 nm) were coated on the textured slider surfaces as a protective overcoat. The friction and wear properties of these sliders were evaluated by constant-speed drag tests against hard disks coated with diamond-like carbon (DLC). The results show that 2 nm texture on a slider surface is sufficient for low (0.3–0.5) and stable friction of the slider against the disk in a drag test, and coatings thicker than 5 nm show similar wear resistances of the texture on slider surfaces. 相似文献