检索结果-南通市图书馆

Multi-Terabit Long-Haul Transmission System Utilizing Distributed Raman Amplification Technologies

在线全文

学校读者我要写书评

暂无评论

光学学报 2003年第S1期23卷 567-568页

作者： takao Naito Toshiki Tanaka Fujitsu Laboratories Ltd. 4-1-1 Kamikodanaka Nakahara-ku Kawasaki 211-8588 JapanFujitsu Laboratories Ltd. 4-1-1 Kamikodanaka Nakahara-ku Kawasaki 211-8588 Japan

Here we summarize multi-terabit long-haul transmission experiment and distributed Raman amplification (DRA) technologies. As well, we investigate the configuration of dispersion-managed fibers for the DRA-based system... 详细信息

关键词： EDFA for very it as of WDM DRA Multi-Terabit Long-Haul Transmission System Utilizing Distributed Raman Amplification Technologies OSNR

Improvement of sail storage and deployment mechanism for spin-type solar power sail

在线全文

学校读者我要写书评

暂无评论

Astrodynamics 2020年第3期4卷 223-231页

作者： Osamu Mori Nobukatsu Okuizumi Toshihiro Chujo Yuki takao Institute of Space and A stronautical Science Japan A erospace Exploration AgencySagamihara 252-5210Japan Department of Mechanical Engineering Tokyo Institute of TechnologyTokyo152-8550Japan Department of Aeronautics and Astronautics the University of TokyoTokyo 113-8654Japan

Deployable membrane structures are expected to be used for large area space structures,such as solar propulsion sails,magnetoplasma sails,drag-deorbiting sails,membrane antennas,and solar power *** are lightweight and can be compactly stored at *** achievement of the Japan Aerospace Exploration Agency(JAXA)was the successful deployment of a 200 m2 sail using centrifugal force in the IKAROS mission,which was the first solar propulsion sail-craft in *** has long been studying the technology of spin deployment of sail membranes,and is currently planning the spin deployment of a class sail larger than 2000 m2 as the next step in the development of the IK AROS *** paper discusses the unexpected behaviors during on-orbit sail deployment by IKAROS,as well as problems with the sail holding method,and proposes an improved sail storage structure and deployment mechanism for the OKEANOS mission.

关键词： solar sail solar power sail storage deployment IKAROS OKEANOS

Transfer of electrons on scratched iron surfaces:Photoelectron emission and X-ray photoelectron spectroscopy studies

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Friction 2018年第1期6卷 98-115页

作者： Yoshihiro MOMOSE Daisuke SUZUKI Keika TSURUYA takao SAKURAI Keiji NAKAYAMA Department of Materials Science Ibaraki University Ashikaga Institute of Technology Institute of Mesotechnology

We report the activation energy, ΔEa, for the quantum yield in thermally assisted photoelectron emission(TAPE) under 210-nm-wavelength light irradiation, and the associated X-ray photoelectron spectroscopy(XPS) results. Samples were cleaned only in acetone and scratched in air, water, methanol, ethanol, acetone, benzene, and cyclohexane. Glow curves, describing the temperature dependence of photoelectron emission(PE) quantum yield(emitted electrons/photon), Y, were obtained. A simple method of determining ΔEa using Y, called YGC, at seven temperatures up to 353 °C, for the same Y glow curve, was proposed. The ΔEa obtained using this method was almost the same as that obtained from Y for seven stationary temperatures(YST). For scratched samples, the TAPE was measured over two cycles of temperature increase and subsequent decrease(Up1, Down1 and Up2, Down2 scans) in the 25–339 °C range, and ΔE_a was obtained from YGC. The Arrhenius plot was approximated by a straight line, although a convex swelling peak appeared in the Up1 scan. ΔE_(aUp1) was in the 0.212–0.035 eV range, depending on the environment in which scratching was performed; ΔE_(aUp1) for water was much higher than that for acetone. This was explained in terms of the mode of the acid–base interaction between the liquid molecules and the hydroxyl group of Fe–OH. The values of ΔE_(aDown1), ΔEa Up2, and ΔE_(aDown2) were in the 0.038–0.012 eV range. The total count of electrons emitted during the Up1 and Up2 scans was found to decrease with increasing ΔE_(aUp1) and ΔE_(aUp2), respectively. ΔE_(aUp2) was found to increase with increasing presence of the FeO component in the analyzed Fe oxides. The convex swelling peak was attributed to the removal of carbon materials from the scratched surface and the effect of the increased electron density of the surface hydroxyl group of FeOH under the light irradiation.

关键词： thermally assisted photoelectron emission XPS real iron scratch-inducing environment Arrhenius activation energy environment molecule-surface hydroxyl group interaction

Study on Blade Surface Flow around Wind Turbine by Using LDV Measurements

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2015年第2期24卷 131-139页

作者： Tinnapob Phengpom Yasunari Kamada takao Maeda Junsuke Murata Shogo Nishimura Tasuku Matsuno Division of System Engineering Mie University Division of Mechanical Engineering Mie University

This paper has attempted to study a mechanism of three-dimensional flow around a horizontal axis wind turbine(HAWT) rotor blade. An experimental study of the flow phenomenon in the vicinity of the wind turbine blade is a challenging endeavor. In this research, the HAWT model with 2.4 m diameter was tested in the large wind tunnel. The flow around the rotating blade surface was measured simultaneously for three velocity components, and two probes were used for the synchronized measurement of three-dimensional flow components. The local velocity was detected for the single seeding particle measured in the point where three pairs of laser beams intersected. Blade sections of interest in this study are composed of radial positions r/R = 0.3, 0.5 and 0.7. Optimum and low tip speed ratio flow characteristics were also compared. The velocity flow vector, skin friction coefficient and bound circulation were calculated from LDV measurements, and the experimental research showed reasonably and clearly the experimental results.

关键词： LDV measurement Sectional performance Wind turbine Boundary layer flow Span-wise flow

PIV Measurements of Flows around the Wind Turbines with a Flanged-Diffuser Shroud

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2008年第4期17卷 375-380页

作者： Kazuhiko Toshimitsu Koutarou Nishikawa Wataru Haruki Shinichi Oono Manabu takao Yuji Ohya Dept.of Mechanical Engineering Oita National College of Technology Kawasaki Precision Machinery Ltd. Honda Motor Co. Ltd. Machine & Electronics Co. Ltd. Dept.of Mechanical Engineering Matsue National Collage of Technology Research Institute of Applied Mechanics Kyushu University

The wind turbines with a flanged-diffuser shroud -so called ＂wind lens turbine＂- are developed as one of high performance wind turbines by Ohya et al. In order to investigate the flow characteristics and flow acceleration, the paper presents the flow velocity measurements of a long-type and a compact-type wind turbines with a flanged-diffuser shroud by particle image velocimetry. In the case of the long type wind turbine, the velocity vec- tors of the inner flow field of the diffuser for turbine blades rotating and no blades rotating are presented at Rey- nolds number, 0.9x105. Fur^thermore the flow fields between with and without rotating are compared. Through the PIV measurement results, one can realize that the turbine blades rotating affects as suppress the disturbance and the flow separation near the inner wall of the diffuser. The time average velocity vectors are made on the av- erage of the instantaneous velocity data. There are two large vortices in downstream region of the diffuser. One vortex behind the flange acts as suck in wind to the diffuser and raise the inlet flow velocity. Another large vortex appears in downstream. It might be act as blockage vortex of main flow. The large blockage vortex is not clear in the instantaneous velocity vectors, however it exists clearly in the time average flow field. The flow field around the wind turbine with a compact-type flanged-diffuser shroud is also investigated. The flow pattern behind the flange of the compact-type turbine is the same as the long-type one. It means that the effect of flow acceleration is caused by the unsteady vortices behind the flange. The comparison with CFD and PIV results of meridional time-average streamlines after the compact-type diffuser is also presented.

关键词： wind turbine PIV wind energy flanged diffuser flow visualization

Electrochemical behavior of [UO_2Cl_4]^(2-) in 1-ethyl-3-methylimidazolium based ionic liquids

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2012年第9期55卷 1699-1704页

作者： OGURA Toshinari SASAKI Kotoe takao Koichiro ARAI Tsuyoshi IKEDA Yasuhisa Research Laboratory for Nuclear Reactors Tokyo Institute of Technology2-12-1-N1-34 O-okayamaMeguro-kuTokyo 152-8550Japan Department of Materials Science Shibaura Institute of Technology3-7-5 ToyosuKoto-kuTokyo 135-8548Japan Department of Materials and Life Science Seikei University3-3-1 Kichijoji-KitamachiMusashino-shiTokyo 180-8633Japan

In order to examine the chemical form of uranyl species in l-ethyl-3-methylimidazolium （EMI） based ionic liquids, UV-visible absorption spectra of solutions prepared by dissolving [EMI]2[UO2CI4] into a mixture of EMICI and EMIBF4 （50：50 tool%） were measured. As a result, it was confirmed that uranyl species in the mixture of EMICI and EMIBF4 existed as [UO2C14]2-. Cyclic voltammograms （CVs） of [UO2CI4]2- in the mixture were measured at 25 ~C using a Pt working electrode, a Pt wire counter electrode, and an Ag/Ag＋ reference electrode （0.01 M AgNO3, 0.1 M tetrabutylammonium perchlorate in acetonitrile） in a glove box under an Ar atmosphere. Peaks corresponding to one redox couple were observed around -1.05 V （Epc） and -0.92 V （Epa） vs. ferrocene/ferrocenium ion （Fc/Fc＋）. The potential differences between two peaks （AEp） increased from 101 to 152 mV with an increase in the scan rate from 50 to 300 mV s-1, while the （Epc ＋ Epa）/2 value was constant, -0.989 V vs. Fc/Fc＋ regardless of the scan rate. Furthermore, the diffusion coefficient of [UO2C14]2 and the standard rate constant were es- timated to be 3.7× 10^-8 cm^2 s 1 and （2.7-2,8） × 10^-4 cm s-! at 25 ℃. By using the diffusion coefficient and the standard rate constant, the simulation of CVs was performed based on the reaction, [UO2C14]2- ＋ e- = [UO2C14]3-. The simulated CVs were found to be consistent with the experimental ones. From these results, it is concluded that [UO2C14]2- in the mixture of EMIC1 and EMIBF4 is reduced to [UO2C14]3- quasi-reversibly at -0.989 V vs. Fc/Fc＋.

关键词： uranyl chloride ionic liquids electrochemistry cyclic voltammetry

Analysis of Aerodynamic Load on Straight-bladed Vertical Axis Wind Turbine

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2014年第4期23卷 315-324页

作者： Qing’an LI takao MAEDA Yasunari KAMADA Junsuke MURATA Toshiaki KAWABATA Kazuma FURUKAWA Division of System Engineering Mie University1577 Kurimamachiya-choTsuMie 514-8507JAPAN Division of Mechanical Engineering Mie University1577 Kurimamachiya-choTsuMie 514-8507JAPAN

This paper presents a wind tunnel experiment for the evaluation of energy performance and aerodynamic forces acting on a small straight-bladed vertical axis wind turbine(VAWT) depending on several values of tip speed ratio. In the present study, the wind turbine is a four-bladed VAWT. The test airfoil of blade is symmetry airfoil(NACA0021) with 32 pressure ports used for the pressure measurements on blade surface. Based on the pressure distributions which are acted on the surface of rotor blade measured during rotation by multiport pressure-scanner mounted on a hub, the power, tangential force, lift and drag coefficients which are obtained by pressure distribution are discussed as a function of azimuthally position. And then, the loads which are applied to the entire wind turbine are compared with the experiment data of pressure distribution. As a result, it is clarified that aerodynamic forces take maximum value when the blade is moving to upstream side, and become small and smooth at downstream side. The power and torque coefficients which are based on the pressure distribution are larger than that by torque meter.

关键词： Wind Turbine Wind Energy Straight-bladed VAWT Tip Speed Ratio Pressure Distribution

Multicolor pattern scan laser for diabetic retinopathy with cataract

在线全文

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2014年第4期7卷 673-676页

作者： takao Hirano Yasuhiro Iesato Toshinori Murata Department of Ophthalmology Shinshu University School of Medicine

· AIM: To evaluate the ability of various laser wavelengths in delivering sufficient burns to the retina in eyes with cataract using a new multicolor pattern scan laser with green(532 nm), yellow(577 nm), and red(647 nm)lasers.·METHODS: The relationship between the Emery-Little(EL) degree of cataract severity and the laser wavelength required to deliver adequate burns was investigated in102 diabetic eyes. Treatment time, total number of laser shots, and intra-operative pain were assessed as well.·RESULTS: All EL-1 grade eyes and 50% of EL-2 eyes were successfully treated with the green laser, while 50%of EL-2 eyes, 96% of EL-3 eyes, and 50% of EL-4 eyes required the yellow laser. The red laser was effective in the remaining 4% of EL-3 and 50% of EL-4 eyes.·CONCLUSION: Longer wavelength lasers are more effective in delivering laser burns through cataract when we use a multicolor pattern scan laser system.

关键词： diabetic macular edema photocoagulation retinal hemorrhage pain photoreceptors

A preliminary investigation on rare earth elements in the brines and sediments of salt lakes, China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1995年第16期40卷 1405-1406页

作者：孙大鹏马育华 takao Oi 李岫霞 Qinghai Institute of Salt Lakes Chinese Academy of Sciences. Xining 810008 China Department of Chemistry Sophia Unnersity Tokyo Japan Institute of Hiph Energy Physics Chinese Academy of Sciences Beijing 100083 China

With the neutron activation analysis, Chinese scientists have determined the rare earthelements in seawater and its sediments, and Japanese scientists have determined the

关键词：大鹏