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A Newly.Developed Non-Destructive Tritium Measurement Technique and Its Application to V-4Cr-4Ti Alloy

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Plasma Science and Technology 2006年第6期8卷 741-744页

作者：刘翔陈学 H.HOMMA y.hatano M.MATSUy.MA Southwestern Institute of Phy.ics Chengdu 610041China Sichuan General Fire Brigade Chengdu 610072China Hy.rogen Isotope Research Centre Toyama UniversityGofuku 3190Toyama 930-8555Japan

A non-destructive and in-situ technique for the measurement of tritium in materials, namely.β-ray.induced X-ray.spectrometry.（BIXS）, has been developed recently. In the present study.a V-4Cr-4Ti alloy.was pre-heated at 1000℃ for 2 h to form a recry.tallization structure before the tritium absorption experiments were conducted. Firstly.the hy.rogen isotope gas was charazterized by.means of a quadrupole mass spectrometer （QMS） and a small-sized ionization chamber. Then hy.rogen isotope absorption tests of V-4Cr-4Ti alloy.were performed at 400 ℃ and the atomic concentration of hy.rogen isotope in V-4Cr-4Ti alloy.was estimated as 0.17% with a tritium content of approximately.2.5 ppm. Experimental results indicate that BIXS is a quite useful tool for quantitatively.measuring the tritium content and tritium distribution in the surface lay.rs of vanadium alloy. and no strong trapping effects of tritium exist in the pre-heated V-4Cr-4Ti alloy.

关键词： tritium V-4Cr-4Ti β-ray.induced X-ray.spectrometry tritium measurements

Study.on Performance and Flow Field of an Undershot Cross-Flow Water Turbine Comprising Different Number of Blades

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Journal of Thermal Science 2017年第5期26卷 413-430页

作者： y.suy.ki Nishi Kentaro hatano Terumi Inagaki Department of Mechanical Engineering Ibaraki University 4-12-1 Nakanarusawa-cho Hitachi-shi Ibaraki 316-8511JAPAN Graduate School of Science and Engineering Ibaraki University 4-12-1 Nakanarusawa-cho Hitachi-shi Ibaraki316-8511 JAPAN

Recently. small hy.roelectric generators have gained attention as a further development in water turbine technology.for ultra low head drops in open channels. The authors have evaluated the application of cross-flow water turbines in open channels as an undershot ty.e after removing the casings and guide vanes to substantially.simplify.these water turbines. However, because undershot cross-flow water turbines are designed on the basis of cross-flow water turbine runners used in ty.ical pipelines, it remains unclear whether the number of blades has an effect on the performance or flow fields. Thus, in this research, experiments and numerical analy.es are employ.d to study.the performance and flow fields of undershot cross-flow water turbines with vary.ng number of blades. The findings show that the turbine output and torque are lower, the fluctuation is significantly.higher, and the turbine efficiency.is higher for runners with 8 blades as opposed to those with 24 blades.

关键词： Water Turbine Cross-Flow Turbine Free Surface Performance Flow Field Number of Blades

Nitrous oxide fluxes from upland soils in central Hokkaido,Japan

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Journal of Environmental Sciences 2008年第11期20卷 1312-1322页

作者： Sonoko D.KIMURA y. TOMA Ry.suke hatano Graduate School of Agriculture Tokyo University of Agriculture and TechnologyTokyo 183-8509Japan Graduate School of Agriculture Hokkaido UniversitySapporo 060-8589Japan

Nitrous oxide (N2O) fluxes from soils were measured using the closed chamber method during the snow-free seasons (middle April to early.November),for three y.ars,in a total of 11 upland crop fields in central Hokkaido,*** annual mean N2O fluxes ranged from 2.95 to 164.17 μgN/(m2·h),with the lowest observed in a grassland and the highest in an onion *** instantaneous N2O fluxes showed a large temporal variation with peak emissions generally.occurring following fertilization and heavy.rainfall eve...

关键词： mineral N pool N2O flux soil upland cropping sy.tem

Nitrogen Flow in the Rural Ecosy.tem of Mikasa City.in Hokkaido, Japan

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Pedosphere 2006年第2期16卷 264-272页

作者： L. LIANG T. NAGUMO R. hatano Graduate School of Agriculture Hokkaido University Sapporo 060-8589 （Japan）. Center for Education and Research of Field Sciences Shizuoka University Fujieda 426-0001 （Japan） Field Science Center for Northern Biosphere Hokkaido University Sapporo 060-8589 （Japan）

This study.of Mikasa City.in 2001, which analy.ed N flow between N production and N load in seven agricultural and settlement subsy.tems, i.e., paddy. onion, wheat, vegetable, dairy. chicken, and citizen subsy.tems, aimed to compare N flow in each subsy.tem, to determine the main sources of the N load, and to evaluate the influence of agricultural production and food consumption on N cy.ling in a rural area. The results showed that in Mikasa city. 38.5% of the N load came from point sources and the remainder from non-point sources with intensive vegetable farming imparting a serious N load. Because of the internal N cy.ling in the dairy.subsy.tem, chemical fertilizer application was reduced by.70.2%, and 23.72 Mg manure N was recy.led to the field; therefore, the N utilization efficiency.was raised from 18.1% to 35.1%. If all the manure N in the chicken subsy.tem was recy.led, chemical fertilizer application would be reduced by.8.1% from the present level, and the point sources of N pollution would be reduced by.20.8%.

关键词： chemical fertilizers ecosy.tem environmental nitrogen load nitrogen flow nitrogen budget

Diffusivity.Models and Greenhouse Gases Fluxes from a Forest,Pasture,Grassland and Corn Field in Northern Hokkaido,Japan

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Pedosphere 2010年第6期20卷 747-760页

作者： N.V.NKONGOLO R.hatano V.KAKEMBO Harvard Forest Faculty of Arts and SciencesHarvard University Laboratory.of Science Division of Environmental ResourcesGraduate School of Agriculture Hokkaido University Department of Geosciences School of Environmental SciencesFaculty of ScienceNelson Mandela Metropolitan University

Information on the most influential factors determining gas flux from soils is needed in predictive models for greenhouse gases emissions. We conducted an intensive soil and air sampling along a 2 000 m transect extending from a forest, pasture, grassland and corn field in Shizunai, Hokkaido （Japan）, measured CO2, CH4, N20 and NO fluxes and calculated soil bulk density.（Pb）, air-filled porosity.（fa） and total porosity.（Ф）. Using diffusivity.models based on either fa alone or on a combination of fa and 4, we predicted two pore space indices： the relative gas diffusion coefficient （Ds/Do） and the pore tortuosity.factor （T）. The relationships between pore space indices （Ds/Do and T） and C02, CH4, N2O and NO fluxes were also studied. Results showed that the grassland had the highest Pb while fa and Ф were the highest in the forest. CO2, CH4, N20 and NO fluxes were the highest in the grassland while N20 dominated in the corn field. Few correlations existed between fa, Ф, Pb and gases fluxes while all models predicted that Ds/Do and T significantly.correlated with CO2 and CH4 with correlation coefficient （r） ranging from 0.20 to 0.80. Overall, diffusivity.models based on fa alone gave higher Ds/Do, lower τ, and higher R2 and better explained the relationship between pore space indices （Ds/Do and τ） and gases fluxes. Inclusion of Ds/Do and τ in predictive models will improve our understanding of the dy.amics of greenhouse gas fluxes from soils. Ds/Do and τ can be easily.obtained by.measurements of soil air and water and existing diffusivity.models.

关键词： air-filled porosity gas diffusion coefficient pore space indices pore tortuosity.factor soil bulk density

Schwarzschild microscopes in vacuum ultraviolet and soft X-ray.regions

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Nuclear Science and Techniques 2005年第3期16卷 129-138页

作者： M.WATANABE M.y.NAGIHARA T.EJIMA M.TOy.DA y.KONDO T.hatano T.TSURU M.y.MAMOTO Institute of Multidisciplinary.Research for Advanced Materials Tohoku University2-1-1 KatahiraAobakuSendai 980-8577Japan

Microscopes in vacuum ultraviolet and soft X-ray.regions using a normal incidence ty.e of Schwarzschild objective are reviewed. The objective consists of a concave mirror and a convex mirror coated with a high reflectance multilay.r,having a large numerical aperture comparing with other objectives. The microscopes have been used to diagnose inertia-confinement-fusion plasmas,and to investigate small samples or microstructures of in- organic and organic materials by.imaging them using laboratory.light sources. Sy.chrotron radiation has been also used to obtain a microbeam for a photoelectron scanning microscope with a spatial resolution of 0.1 μm. The struc- ture and performance of two laboratory.microscopes developed at Tohoku University.are demonstrated. One of them is a soft X-ray.emission imaging microscope. An image of an artificial pattern made of W and SiO2 on Si wafer by.focusing Si L emission was presented. The other is an ultraviolet photoelectron scanning microscope using a He (he- lium) gas discharge lamp. The valence band spectra of a microcry.tal of FeWO4 were presented. Furthermore other applications such as demagnify.ng optics for lithography.and optics to gather fluorescence for emission spectroscopy.are introduced.

关键词：施瓦兹希尔物镜真空紫外线辐射软X-射线显微镜光电子

Millimeter-Wave Concurrent Beamforming:A Multi-Play.r Multi-Armed Bandit Approach

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Computers, Materials & Continua 2020年第12期65卷 1987-2007页

作者： Ehab Mahmoud Mohamed Sherief Hashima Kohei hatano Hani Kasban Mohamed Rihan Electrical Engineering Department College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addwasir11991Saudi Arabia Electrical Engineering Department Faculty of EngineeringAswan UniversityAswan81542Egypt Computational Learning Theory.Team RIKEN-Advanced Intelligent ProjectFukuoka819-0395Japan Engineering Department Nuclear Research CenterEgyptian Atomic Energy AuthorityCairo13759Egypt Faculty.of Arts and Science Kyushu UniversityFukuok819-0395Japan Electronics and Electrical Communication Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

The communication in the Millimeter-wave(mmWave)band,i.e.,30~300 GHz,is characterized by.short-range transmissions and the use of antenna beamforming(BF).Thus,multiple mmWave access points(APs)should be installed to fully.cover a target environment with gigabits per second(Gbps)***,inter-beam interference prevents maximizing the sum rates of the established concurrent *** this paper,a reinforcement learning(RL)approach is proposed for enabling mmWave concurrent transmissions by.finding out beam directions that maximize the long-term average sum rates of the concurrent ***,the problem is formulated as a multiplay.r multiarmed bandit(MAB),where mmWave APs act as the play.rs aiming to maximize their achievable rewards,i.e.,data rates,and the arms to play.are the available beam *** this setup,a selfish concurrent multiplay.r MAB strategy.is *** different MAB algorithms,namely.ϵ-greedy.upper confidence bound(UCB),Thompson sampling(TS),and exponential weight algorithm for exploration and exploitation(EXP3)are examined by.employ.ng them in each AP to selfishly.enhance its beam selection based only.on its previous *** a few rounds of interactions,mmWave APs learn how to select concurrent beams that enhance the overall sy.tem *** proposed MAB based mmWave concurrent BF shows comparable performance to the optimal solution.

关键词： Millimeter wave(mmWave) concurrent transmissions reinforcement learning multiarmed bandit(MAB)

High-density.circulating fluidized bed gasifier for advanced IGCC/IGFC-Advantages and challenges

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Particuology 2010年第6期8卷 602-606页

作者： Guoqing Guan Chihiro Fushimi Atsushi Tsutsumi Masanori Ishizuka Satoru Matsuda Hiroy.ki hatano y.shizo Suzuki Collaborative Research Center for Energy.Engineering Deportment of Mechanical and Biolhnctional Systems Institute of Industrial Science The University of Tokyo 4-6-1 Komaba Meguoro-ku Tokyo 153-8505Japan Clean Gas Group National Institute of Advanced Industrial Science and Technology 16- 1 Onogawa Tsukuba Iboraki 305-8569Japan

Coal-fired Integrated Gasification Combined Cy.le （IGCC） and Integrated coal Gasification Fuel-cell Com- bined cy.le （IGFC） are being developed as high-efficiency.electric power generation technology. However, the highest theoretical gross thermal efficiency.of the conventional IGCC]IGFC is still below 52~. In order to obtain higher power generation efficiency. an advanced IGCC （A-IGCC） or advanced IGFC （A-IGFC） sy.- tem making use of the exergy.recuperation concept by.recy.ling waste heat from gas turbine or fuel cells for steam gasification of coal and biomass was proposed in our laboratory. Corresponding to this sy.tem, a novel high-density.triple-bed combined circulating fluidized bed （TBCFB） gasifier, composed of a downer py.oly.er, a bubbling fluidized bed char gasifier, and a riser combustor, was proposed to replace traditional gasifiers such as the entrained flow bed gasifier. The new sy.tem is expected to more effectively.utilize the waste heat from gas turbines or fuel cells and the heat produced by.the combustion of the unreacted char in the riser combustor for py.oly.is and gasification of coal and biomass. In this short review, the advantages and future challenges in the development of high-density.TBCFB gasifier are presented and discussed.

关键词： IGCC/IGFC High-density.circulating fluidized bed Gasifier Riser Downer Bubbling fluidized bed Exergy.recuperation Biomass Coal

Evaluation of pharmaceutical powder flowability.by.a new shear-cell test method

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Evaluation of pharmaceutical powder flowability by a new she...