检索结果-南通市图书馆

Electroactive species study in the electrochemical reduction of CO_2 in KHCO_3 solution at elevated temperature

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2016年第3期25卷 517-522页

作者： Heng Zhong Katsushi Fujii yoshiaki nakano Research Center for Advanced Science and Technology The University of Tokyo Global Solar Plus Initiative The University of Tokyo Department of Electrical Engineering and Information Systems School of Engineering The University of Tokyo

Photoelectrochemical and electrochemical reduction of CO_2 into organic chemicals is promising for directly or indirectly transforming solar energy into chemical energy for further utilization. However,research on the electroactive species in these processes has been rather limited. In this work, we investigated possible electroactive species(CO_2 or HCO_3~– ) involved in the electrochemical reduction of KHCO_3 at elevated temperatures without CO_2 bubbling. The results showed that CO, CH_4, and C_2H_4 were produced after electrochemical reduction of 3.0 mol/L KHCO_3 at elevated temperature on a Cu electrode even without CO_2 bubbling, although their faradaic efficiencies were low(< 6 %). Measurements for CO_2 generation from the decomposition of HCO_3~– showed that elevated temperature and high HCO_3~– concentration strongly promoted this process. These results suggested that the in-situ produced CO_2 from the decomposition of HCO_3~– was probably the electroactive species in the electrochemical reduction of HCO_3~– without CO_2 bubbling. Changes of the Gibbs free energy, rate constant, and activation energy of the decomposition of HCO_3~– into CO_2 were also investigated and calculated from the experimental data.

关键词： CO_2 reduction Electrolytic Electroactive species KHCO_3 electrolyte Bicarbonate ion decomposition Kinetics

InGaAsP/InP DH Ridge Waveguide Phase Modulator with High Modulation Efficiency

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 289-290页

作者： Young Tae Byun Hwa Sun Park Sung Jin Kim Deok Ha Woo Jong Chang Yi yoshiaki nakano Photonics Research Center Korea Institute of Science and Technology Seoul Korea School of Electronics and Electrical Engineering Hong Ik University Seoul Korea Research Center for Advanced Science and Technology University of Tokyo Tokyo Japan

The P-p-n-N InGaAsP/InP ridge waveguide phase modulator has been fabricated and investigated at a wavelength of 1550nm. The phase modulation efficiency measured by the Fabry-Perot resonance method is as high as 34°/V... 详细信息

关键词： phase modulation ridge waveguide

Efects of amine, amine salt and amide on the behaviour of carbon dioxide absorption into calcium hydroxide suspension to precipitate calcium carbonate

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2013年第12期25卷 2507-2515页

作者： Wittaya Chuajiw Mitsuru nakano Kazumasa Takatori Toshiya Kojima Yoshiki Wakimoto yoshiaki Fukushima Toyota Technological Institute 2-12-1 HisakataTempaku-kuTenpaku Moon Chome Toyota Central R&D Labs. Inc. Yokomichi Aisin Seiki Co. Ltd.2-1Asahi-machi

The amount of carbon dioxide （CO2） absorption and calcium ion （Ca^2＋） concentration besides the pH of aqueous solution were observed during the COz absorption to precipitate calcium carbonate （CaCO3） from calcium hydroxide （Ca（OH）2）. A reaction rate-limiting effect of an amount of CO2 absorption without any organic additives in the early stage of the precipitation was observed, which was attributed to an interruption effect of bicarbonate ion （HCO3） on the precipitation of CaCO3. The improvement for the reaction rate was achieved not only by amine additives but also by neutral additives such as ε-caprolactam or amine salt. When the hexamethylene diamine was dissolved in the solution, successive change of crystal forms of CaCO3 aragonite to calcite in aqueous suspensions, confirmed by Ca^2＋ concentration change and X-ray diffraction, was concluded that a local environment around the amine group in aqueous solution and an interaction of the diamine with precipitated CaCO3 particles were important factors for these reactions.

关键词： carbon dioxide absorption calcium carbonate precipitation local functional group interaction

Non-cooperative optimization games in market-oriented overlay networks： an integrated model of resource pricing and network formation

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2011年第4期5卷 496-505页

作者： Yutaka OKAIE Tadashi nakano Graduate School of Engineering Osaka University Suita Osaka 565-0871 Japan

In this paper, we formulate a non-cooperative optimization game in market-oriented overlay networks where participating peers share their own computing resources to earn virtual money called energy. We model an overlay network as a set of non-cooperative resource providing peers, called platforms, that perform resource pricing and topology management to maximize their own energy gains. Resource consuming peers, called agents, are simply designed to migrate platform-to-platform to find the least expensive resources in the network. Simulation results are presented to demonstrate the market dynamics as well as the global properties of the network, i.e., resource price and network topology, that emerge from local interactions among the group of peers.

关键词： Overlay networks market mechanisms non-cooperative games mobile agents

Potential effects of mesenchymal stem cell derived extracellular vesicles and exosomal miRNAs in neurological disorders

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

Neural Regeneration Research 2021年第12期16卷 2359-2366页

作者： Masako nakano Mineko Fujimiya Department of Anatomy Sapporo Medical University School of MedicineSapporoHokkaidoJapan

Mesenchymal stem cells are multipotent cells that possess anti-inflammatory,antiapoptotic and immunomodulatory *** effects of existing drugs for neurodegenerative disorders such as Alzheimer’s disease are limited,thus mesenchymal stem cell therapy has been anticipated as a means of ameliorating neuronal *** mesenchymal stem cells are known to scarcely differentiate into neuronal cells in damaged brain after transplantation,paracrine factors secreted from mesenchymal stem cells have been suggested to exert therapeutic *** vesicles and exosomes are small vesicles released from mesenchymal stem cells that contain various molecules,including proteins,mRNAs and *** recent years,administration of exosomes/extracellular vesicles in models of neurological disorders has been shown to improve neuronal dysfunctions,via exosomal transfer into damaged *** addition,various microRNAs derived from mesenchymal stem cells that regulate various genes and reduce neuropathological changes in various neurological disorders have been *** review summarizes the effects of exosomes/extracellular vesicles and exosomal microRNAs derived from mesenchymal stem cells on models of stroke,subarachnoid and intracerebral hemorrhage,traumatic brain injury,and cognitive impairments,including Alzheimer’s disease.

关键词： exosomes extracellular vesicles mesenchymal stem cells microRNA neurological disorders

Novel Phase Transition in BaPr_2Mn_2O_7

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2006年第Z2期24卷 1-3页

作者： Hiromi nakano Naoki Kamegashira Ryukoku University SetaOtsu 520-2194Japan Toyohashi University of Technology Tenpaku-choToyohashi 441-8580Japan

The rare earth manganite BaLn2Mn2O7(Ln = rare earth element) has a Sr3Ti2O7-type layered perovskite structure with double-block oxygen octahedra belonging to the Ruddlesden-Popper-type homologous series AO(ABO3)2. In Pr-manganite, a novel phase transition was first observed in situ at 1040 K by a thermal transmission electron microscope. At 1040 K, reflections began to split along the c-direction in the selected area diffraction pattern. This indicates that a new phase appears in the original phase matrix; the c length of the new phase is 1.5% longer than that of the original phase. After about 5 min, the original phase disappears. No change in the crystal symmetry (space group 14/mmm) is observed above 1040 K.

关键词： rare earth manganite phase transition transmission electron microscope (TEM)

Flat friction stir spot welding of low carbon steel by double side adjustable tools

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第7期66卷 1-9页

作者： Xiaopei Wang yoshiaki Morisada Hidetoshi Fujii Joining and Welding Research Institute Osaka University11-1 MihogaokaIbarakiOsaka 567-0047Japan

2 mm low carbon steel plates were successfully welded by the flat friction stir spot welding(FSSW) using double side adjustable tools, by which the keyhole formed in the conventional FSSW was eliminated and a flat surface on both the top and bottom sides of the welded joints was obtained. In addition, the hook shape usually generated in the conventional FSSW was eliminated by this technique, and the unbonded interface was parallel to the surface of the sheets. Owing to the enlarged bonded interface width by eliminating the keyhole and the intermixed interface by the adjustable probe, the plug fracture occurred under all the welding conditions in the present study. Due to the suppression of the thickness thinning and elimination of the hook shape, the joint performance was improved in the plug fracture mode. The shear tensile performance was considered to strongly depend on the microstructure in the tip area of the unbonded interface and the maximum shear fracture load of 23.0 kN was achieved in this study.

关键词： Friction stir spot welding Interface structure Low carbon steel Mechanical properties Microstructure

Effect of Exit Geometry of Tail Pipe on the Performance of Pulse Jet Engines

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2006年第3期15卷 263-268页

作者： Toshihiro nakano ShigeruMATSUO KenbuTERAMOTO ToshiakiSETOGUCHI Department of Mechanical Engineering Saga University1 Honjo-machiSaga-shiSaga 840-8502Japan

In this paper,the effect of geometries of tube open end on the shock,compression and expansion wavespropagating in the tube was investigated numerically and *** of them is a conventional straightshock tube with an open *** other has a divergent tail tube at the *** a divergent tail tube(flaretube)to an open end shock tube,the period of one-cycle process could be shortened and the pressure behind theexpansion wave produced at the exit of the shock tube could be lowered much more below the atmosphericpressure than that produced in the straight *** results suggested that the intake air into the engine wassignificantly increased by applying a flare tube instead of a straight tube.

关键词： compressible flow shock wave expansion wave pulse jet numerical simulation

Interface strengthening in dissimilar double-sided friction stir spot welding of AZ31/ZK60 magnesium alloys by adjustable probes

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第26期85卷 158-168页

作者： Xiaopei Wang yoshiaki Morisada Hidetoshi Fujii Joining and Welding Research Institute Osaka University11-1 MihogaokaIbarakiOsaka 567-0047Japan

Dissimilar welding of AZ31/ZK60 magnesium alloys with a thickness of 2 mm was successfully carried out by the double-sided friction stir spot welding with adjustable probes.A dissimilar joint bearing flat surfaces on both sides without a keyhole was obtained and the shear failure load of 8.7±0.5 kN was *** role of the adjustable probes has been revealed in *** the center of the stir zone,the welding interface structure was heterogeneous around which some distinct oxides still remained,leading to a weak interface *** the contrary,the welding interface structure around the shoulder/probe interface was homogeneous with no oxides giving rise to a strong interface strength,which is attributed to the severe material flow introduced by the adjustable *** addition,the vicinity outside the shoulder/probe interface,where the fracture occurred during the shear tensile tests,was also strengthened owing to the shearing and torsion by the adju stable ***,a stable plug failure can be obtained and the joint properties can be improved.

关键词： Friction stir spot welding Dissimilar welding Interface strengthening Microstructure Magnesium alloys