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排序方式: 共有1205条查询结果,搜索用时 15 毫秒
101.
Kenta Arima Katsuyoshi Endo Toshihiko Kataoka Kikuji Hirose Hidekazu Goto Yasushi Oshikane Haruyuki Inoue Yoshitaka Tatara Yuzo Mori 《Computational Materials Science》1999,14(1-4):236-240
Local density of states (LDOS) is obtained by the first principles calculation based on the density functional theory on the Si(0 0 1)2 × 1 surface and on the surface with an Al dimer. At an Al dimer, LDOS has a high intensity in the conduction band region, which cannot be seen on the Si(0 0 1)2 × 1 surface. This tendency is observed in STS measurements as well. The possibility for a microelementary analysis is presented by applying this method to other metal atoms on the Si surface. Furthermore, it is pointed out that STS measurements should be always performed at the same tip-sample separation to obtain reproducible STS spectrums. 相似文献
102.
The study aims to evaluate the potential of GHG (greenhouse gas) reductions by installing an anaerobic digester in a wastewater treatment facility in Southeast Asia. Then the break-even point of additional investment to reduce GHG is obtained by exchanging carbon price as emissions credits. In the project scenario, the wastewater treatment system has the digester, where methane (biogas) is produced and recovered. Compared with the baseline scenario, the biogas has calorific value to produce heat and electri... 相似文献
103.
The isothermal curing process of bisphenol A epoxy resin with polyamine reagent (1,6‐diaminohexane) was monitored in situ by using temperature‐controlled Fourier‐transform infrared (FTIR) and Fourier‐transform near infrared (FTNIR) spectroscopy to elucidate the relative changes in functional groups during the curing reaction. It was shown that generalized two‐dimensional correlation spectroscopy can provide new information about the mechanisms and kinetics of the curing process, and the band assignments for complex NIR spectrum associated with this system. The sequential order of relative changes in functional groups during the curing process was examined by generalized 2D correlation spectroscopy and NIR‐IR hetero‐correlation spectroscopy, and the details of the complex epoxy curing reaction involving both primary and secondary amino group were revealed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
104.
Toshihiko Noguchi Yosuke Takata Yukio Pyamashita Yoshimi Komatsu Seiichi Ibaraki 《Electrical Engineering in Japan》2007,161(3):31-40
This paper describes an ultrahigh‐speed permanent‐magnet synchronous motor drive, which is embedded in a turbocharger of an internal‐combustion engine. The electrical drive makes it possible to enhance output power of the turbocharger in a motoring mode and to retrieve combustion energy from exhaust gas in a regenerating mode. Computer simulations and experimental tests are conducted to examine various operation characteristics of a prototype. The experimental data demonstrate 220,000‐r/min operation at 2.2‐kW inverter output power, in good agreement with the simulation results and proving the feasibility of the proposed system. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 161(3): 31–40, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20408 相似文献
105.
This paper focuses on a maximum‐power‐point tracking method of photovoltaics via use of the short‐current pulse. It has been reported that the optimum operating current is proportional to the short current and that maximum‐power‐point tracking can be performed by detecting the short current. The proposed method utilizes the intermittent short‐current pulse to estimate the optimum operating current and its operating characteristics have experimentally been verified. Also, an adaptive mechanism to identify the parameter between the optimum current and the short current is discussed. A prototype of the controller has been set up and the experimental results have demonstrated excellent performance, proving the feasibility of the system. © 2002 Scripta Technica, Electr Eng Jpn, 139(1): 65–72, 2002; DOI 10.1002/eej.1147 相似文献
106.
H Sawada H Morimoto A Wake Y Yamasaki Y Izumi M Kuroiwa S Osabe Y Imamura K Egami A Tsukamoto I Sanada T Kiyokawa F Kawano 《Canadian Metallurgical Quarterly》1998,39(11):1085-1091
Thirty patients (median age of 32 years; range, 6-61) with hematologic disorders received unmanipulated peripheral blood stem cell transplants from HLA-matched or one-antigen-mismatched related donors following myeloablative therapy for acute lymphoblastic leukemia (7), acute myelogenous leukemia (6), chronic myelogenous leukemia (8), myelodysplastic syndrome (3), or other disorders (6). Granulocyte colony stimulating factor (G-CSF) mobilized peripheral blood stem cells were collected from donors in 1 to 3 aphereses. The apheresis products contained mean counts of 11.3 x 10(8) (range, 3.8-17.2) nucleated cells/kg and 6.7 x 10(6) (range, 1.3-16.7) CD34+ cells/kg. Graft-versus-host-disease (GVHD) prophylaxis consisted of cyclosporin A plus methotrexate, or FK506 plus methotrexate. All patients received G-CSF following their transplant. Although 1 patient died of pneumonia 6 days after transplantation, the others demonstrated rapid engraftment. Median days to recovery to 500/microliter neutrophils and 20,000/microliter platelets were 13 (range, 8-21) and 14 (range, 1-23) days, respectively. The incidence of acute GVHD grade II-IV was 33%; chronic GVHD developed in 57% of the assessable patients. There were no episodes of graft failure or rejection. Nineteen patients (63%) were alive and in complete remission from 147 to 839 days following their transplant (median follow-up of 560 days). Further follow-up study will be required to assess the incidence of chronic GVHD and graft-versus-leukemia (GVL) effects. 相似文献
107.
Controller-integrated predictive oscillation compensation for machine tools with parallel kinematics 总被引:1,自引:1,他引:0
C. Brecher M. Weck T. Yamasaki 《International Journal of Machine Tools and Manufacture》2006,46(2):142-150
Since computerised numerical control (CNC) systems were introduced into the field of mechanical engineering, the manufacturing technology made significant progress. In spite of drastic improvements, mainly in terms of productivity and precision (e.g. finishing surface quality), opportunities for further advancements for the manufacturing processes still exist. One possible method for increasing precision is to adopt a machine structure with parallel kinematics. This kinematic structure can enhance the system dynamics, because the moving mass is divided among all actuators, contrary to the conventional, cartesian machine structures. The problem, which still exists even with this new structural solution, is the machine oscillation that appears during machining. This oscillation may decrease the machining accuracy. This paper highlights a new possible method to compensate the machine oscillation by using a controller-integrated compensation principle. Because of this principle, additional mechanical components (e.g. piezo stacks, actuators) are not necessary. This compensation concept was developed and verified under Matlab/SIMULINK and then installed into the machining centre Dyna-M. The kinematic structure of Dyna-M is defined as a hybrid-kinematic and also one of the typical parallel structures. The obtained results show up to 60% reduction of the machine oscillation and prove the practical usability of this compensation system. 相似文献
108.
Toshihiko Hirama Masashi Goto Toshiyasu Hasegawa Minoru Kanechika Takahiro Kei Tsutomu Mieda Hiroshi Abe Katsuki Takiguchi Hiroshi Akiyama 《Nuclear Engineering and Design》2005,235(13):1128
In Japan, the Nuclear Power Engineering Corporation (NUPEC), sponsored by the Ministry of Economy, Trade and Industry (METI), has been conducting a series of seismic reliability proving tests using full-scale or close to full-scale models to simulate actual important equipment that is critical for seismic safety of nuclear power plants. The tests are intended to validate the seismic design and reliability with a sufficient margin even under destructive earthquakes. A series of tests was carried out on a reinforced concrete containment vessel (RCCV) for advanced boiling water reactor (ABWR) from 1992 to 1999. A large-scale high-performance shaking table at Tadotsu Engineering Laboratory, the largest in the world, was used for this test. Part 1 reports the test model and the results of pressure and leak tests. Part 2 describes test procedures, input waves and the results of verification tests such as changes of stiffness, characteristic frequency and damping ratio, the failure of the model and the load deflection. Part 3 shows the seismic safety margin that was evaluated from the energy input during the failure test to a design basis earthquake. Part 4 reports simulation analysis results by a stick model with lumped masses. 相似文献
109.
Thin metal films often exhibit interesting properties that are essentially different from the bulk ones. XAFS (X-ray absorption fine structure) and XMCD (X-ray magnetic circular dichroism) techniques are quite suitable to investigate structural, thermal and magnetic properties of thin metal films. In this proceeding, we will present following two topics concerning structural and magnetic properties of adsorbates on thin metal films. The first one is the adsorption geometry of SO2 on a 1-monolayer (ML) Pd thin film grown on a Ni(111) single crystal. It was found by S K-edge XAFS that SO2 is lying flat on 1-ML Pd/Ni(111). This result is not similar to the bulk Pd surface but to the bulk Ni one. This finding indicates significant modification of the electronic structure of the 1-ML Pd film compared to the bulk one. The second topic is the magnetic moment induced on CO adsorbed on Ni epitaxial films grown on Cu(001). The O K-edge XMCD results revealed that in the perpendicularly magnetized 10-ML Ni film the orbital moment of CO is parallel to the substrate Ni magnetization, while it is antiparallel in the in-planar magnetized 6-ML and thick (>100 ML) films. The origin of the induced orbital moment at CO is discussed. 相似文献
110.
S Wakatsuki SC Ho M Arioka M Yamasaki K Kitamoto 《Canadian Metallurgical Quarterly》1997,122(6):1146-1152
By screening with monoclonal antibodies (mAbs) raised against growth cone membrane fraction from fetal porcine brains, we have identified a 230 kDa antigen, termed p230. Western blot analysis of extracts from various tissues demonstrated that p230 is specifically expressed in brains, in which its expression is temporally restricted; it was especially prominent in the embryonic and the early postnatal stage, and decreased to subdetectable levels in the adult brain. Further characterization of p230 revealed that it is a peripherally-membrane associated, cell surface protein produced by astrocytes. Neurite outgrowth of E18 rat cerebral cortex neurons cultured on a monolayer of astrocytes was significantly reduced in the presence of anti-p230 polyclonal antibody. Partial amino acid sequences of p230 purified from fetal porcine brains were highly homologous to an extracellular matrix protein, tenascin-C. These lines of evidence suggest that p230, a tenascin-C-like molecule present in fetal porcine brains, plays important roles during early brain development, particularly in growth cone guidance. 相似文献