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Correlations between Mineral Nitrogen Contents and Vertical Distribution of N20 Emission Potentials in Tropical Peat Soils Transformed into Oil Palm Plantations in Sarawak, Malaysia

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Journal of Agricultural Science and Technology(B) 2014年第9期4卷 691-700页

作者： Sharon Yu Ling Lau Yasuyuki Hashidoko Naoki Takahashi ryusuke hatano Lulie Melling Research Faculty of Agriculture Hokkaido University Kita 9 Nishi 9 Kita-ku Sapporo 060-8589 Japan Tropical Peat Research Laboratory Unit Jalan Badruddin Kuching 93400 Malaysia

Tropical peat swamp forest beds that have been reclaimed for agricultural use are generally an active source of nitrous oxide (N2O) efflux, however, the mechanism by which reclaimed tropical peat soils promote the emergence of N2O emitters in soil microbial communities remains unclear. The purpose of this study was to reveal the vertical distribution of N2O emission potential and its correlation with mineral nitrogen contents in reclaimed soils. Using a culture-based N2O emission assay, the N2O emission potentials of soil at various depths (0‐450 cm) were investigated in two oil palm plantations in Sarawak, Malaysia, which had elapsed times of two years (E2Y) and 10 years (E10Y) after deforestation, respectively. On the basis of the relationship between the vertical profiles of N2O emission potentials and the contents of mineralized nitrogen in the peat soils at various depths, the impact of land management on soil microbial communities was discussed. The peat soil at plantation site E2Y showed a trend of high N2O production in deep layers (200-400 cm), whereas the older plantation site E10Y showed considerably more active N2O emission in shallow soil (10-50 cm). N2O emission potentials among the soil microbial communities at different soil depths at the E10Y site showed positive correlations with NO3 - and NH4 + contents, whereas, soils obtained from the E2Y site had N2O emission potentials that were inversely proportional to the contents of NO3 -. This contrasting vertical correlation between N2O-emitting potentials and mineralized nitrogen contents in bulk soils suggests that active N2O emission in deep soil at the E2Y site has maintained the original carbon-nitrogen (C/N) ratio of the peat soil, whereas at E10Y, such a regulatory system has been lost due to advanced soil degradation, leading to dynamic changes in the nitrogen cycle in shallow soil.

关键词： N2O排放量垂直分布马来西亚泥炭土氮含量种植园沙捞越油棕榈

Modeling the biomass of energy crops：Descriptions, strengths and prospective

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Journal of Integrative Agriculture 2017年第6期16卷 1197-1210页

作者： JIANG Rui WANG Tong-tong SHAO Jin GUO Sheng ZHU Wei YU Ya-jun CHEN Shao-lin hatano ryusuke Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China Ministry of Agriculture/College of Natural Resources and Environment Northwest A&F University Yangling 712100 P.R.China Biomass Energy Center for Arid and Semi-arid Lands Northwest A&F University Yangling 712100 P.R. China College of Water Resources and Architectural Engineering Northwest A&F University Yangling 712100 P.R. China College of Geography Sciences Shanxi Normal University Linfen 041000 P.R. China Graduate School of Agriculture Hokkaido University Sapporo 060-8589 Japan

The assessment of the biomass of energy crops has garnered widespread interest since renewable bioenergy may become a substantial proportion of the future energy supply, and modeling has been widely used for the simulation of energy crops yields. A literature survey revealed that 23 models have been developed or adapted for simulating the biomass of energy crops, including Miscanthus, switchgrass, maize, poplar, willow, sugarcane, and Eucalyptus camaldulensis. Three categories（radiation model, water-controlled crop model, and integrated model with biochemical and photosynthesis and respiration approaches） were addressed for the selected models according to different principles or approaches used to simulate biomass production processes. EPIC, ALMANAC, APSIM, ISAM, MISCANMOD, MISCANFOR, SILVA, DAYCENT, APEX and SWAT are radiation models based on a radiation use efficiency approach（RUE） with few empirical and statistical parameters. The Aqua Crop model is a typical water-crop model that emphasizes crop water use, the expression of canopy cover, and the separation of evapotranspiration to soil evaporation and plant transpiration to drive crop growth. CANEGRO, 3PG, Crop Syst and DSSAT are integrated models that use photosynthesis and respiration approaches. SECRETS, LPJm L, Agro-BGC, Agro-IBIS, and WIMOVAC/Bio Cro, DNDC, DRAINMOD-GRASS, and Ag TEM are integrated models that use biochemical approaches. Integrated models are mainly mechanistic models or combined with functional models, which are dynamic with spatial and temporal patterns but with complex parameters and large amounts of input data. Energy crop models combined with process-based models, such as EPIC in SWAT and CANEGRO in DSSAT, provide good examples that consider the biophysical, socioeconomic, and environmental responses and address the sustainability and socioeconomic goals for energy crops. The use of models for energy crop productivity is increasing rapidly and encouraging; however, relevant databases, such as climate, land use/land cover, soil, top

关键词： biomass energy crops models database principles

区域粮食生产和消费中的氮素循环及向环境中的输出

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农业系统科学与综合研究 2008年第3期24卷 289-291页

作者：韩秉进波多野隆介中国科学院东北地理与农业生态研究所黑土生态重点实验室黑龙江哈尔滨150081 日本北海道大学大学院

地球变暖化、富营养化和酸性化是人类面临的严重生态环境问题。研究表明,这些问题的产生是氮碳循环量增加和向环境输出量增加的原因造成的。尤其是农田N的投入量年年在增加,N2O、N-NO3-发生量在迅速增长,对大气和地下水的影响日益严重... 详细信息

地球变暖化、富营养化和酸性化是人类面临的严重生态环境问题。研究表明,这些问题的产生是氮碳循环量增加和向环境输出量增加的原因造成的。尤其是农田N的投入量年年在增加,N2O、N-NO3-发生量在迅速增长,对大气和地下水的影响日益严重。结合氮素循环研究现状,重点阐述氮素流通量收支模型的构成要素、如何根据氮素流通量收支模型推定农田的剩余氮素和废弃氮素,并简明扼要地阐明了向环境输出的氮素引发赤潮、地球变暖、酸化的过程及机理。

关键词：氮素循环粮食生产氮素负荷环境监测

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： Yasuyuki 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 hydroelectric 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 type 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 typical 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 analyses are employed to study the performance and flow fields of undershot cross-flow water turbines with varying 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：水轮机技术导流叶片性能流场小型水轮发电机水轮机转轮同数贯流式水轮机

Nitrogen Flow in the Rural Ecosystem 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 analyzed N flow between N production and N load in seven agricultural and settlement subsystems, i.e., paddy, onion, wheat, vegetable, dairy, chicken, and citizen subsystems, aimed to compare N flow in each subsystem, to determine the main sources of the N load, and to evaluate the influence of agricultural production and food consumption on N cycling 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 cycling in the dairy subsystem, chemical fertilizer application was reduced by 70.2%, and 23.72 Mg manure N was recycled to the field; therefore, the N utilization efficiency was raised from 18.1% to 35.1%. If all the manure N in the chicken subsystem was recycled, 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：化学肥料生态系统生态环境氮承载量

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 CO 2 ,CH 4 ,N 2 O and NO fluxes and calculated soil bulk density (ρ b ),air-filled porosity (f a ) and total porosity (Φ).Using diffusivity models based on either f a alone or on a combination of f a and Φ,we predicted two pore space indices: the relative gas diffusion coefficient (D s /D o ) and the pore tortuosity factor (τ).The relationships between pore space indices (D s /D o and τ) and CO 2 ,CH 4 ,N 2 O and NO fluxes were also studied.Results showed that the grassland had the highest ρ b while f a and Φ were the highest in the forest.CO 2 ,CH 4 ,N 2 O and NO fluxes were the highest in the grassland while N 2 O dominated in the corn field.Few correlations existed between f a ,Φ,ρ b and gases fluxes while all models predicted that D s /D o and τ significantly correlated with CO 2 and CH 4 with correlation coefficient (r) ranging from 0.20 to 0.80.Overall,diffusivity models based on f a alone gave higher D s /D o ,lower τ,and higher R 2 and better explained the relationship between pore space indices (D s /D o and τ) and gases fluxes.Inclusion of D s /D o and τ in predictive models will improve our understanding of the dynamics of greenhouse gas fluxes from soils.D s /D o and τ can be easily obtained by measurements of soil air and water and existing diffusivity models.

关键词：温室气体排放量扩散系数预测模型北海道玉米田通量森林草地

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.MATSUYAMA Southwestern Institute of Physics Chengdu 610041China Sichuan General Fire Brigade Chengdu 610072China Hydrogen 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 recrystallization structure before the tritium absorption experiments were conducted. Firstly the hydrogen isotope gas was charazterized by means of a quadrupole mass spectrometer （QMS） and a small-sized ionization chamber. Then hydrogen isotope absorption tests of V-4Cr-4Ti alloy were performed at 400 ℃ and the atomic concentration of hydrogen 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 layers of vanadium alloys 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

Millimeter-Wave Concurrent Beamforming:A Multi-Player 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)connectivity.However,inter-beam interference prevents maximizing the sum rates of the established concurrent links.In 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 links.Specifically,the problem is formulated as a multiplayer multiarmed bandit(MAB),where mmWave APs act as the players aiming to maximize their achievable rewards,i.e.,data rates,and the arms to play are the available beam directions.In this setup,a selfish concurrent multiplayer MAB strategy is advocated.Four 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 employing them in each AP to selfishly enhance its beam selection based only on its previous observations.After a few rounds of interactions,mmWave APs learn how to select concurrent beams that enhance the overall system performance.The 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)

Microstructure,hardening and deuterium retention in CVD tungsten irradiated with neutrons at temperatures of defect recovery stagesⅡandⅢ

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Tungsten 2022年第3期4卷 248-260页

作者： Xiao-Ou Yi Tatsuya Kuwabara Vladimir KhAlimov Yu-Feng Du Wen-Tuo Han Ping-Ping Liu Bin-You Yan Jiu-Peng Song Kenta Yoshida Takeshi Toyama Fa-Rong Wan Somei Ohnuki Yuji hatano Yasuyoshi Nagai School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Graduate School of Engineering Nagoya UniversityFuro-choChikusa-kuNagoya464-8063Japan Frumkin Institute of Physical Chemistry and Electrochemistry Russian Academy of SciencesMoscow119071Russia Institute for Materials Research Tohoku UniversityNarita-cho 2145-2OaraiIbaraki311-1313Japan Xiamen Tungsten Co.Ltd. Xiamen361021China School of Materials Science and Engineering Xihua UniversityChengdu610039China Hydrogen Isotope Research Center University of ToyamaToyama930-8555Japan

Samples of ultra-high-purity tungsten prepared using chemical vapour deposition(CVD)technique were irradiated with neutrons at temperatures T_(irr)=373-483 K(stage Ⅱ of defect recovery)and T_(irr)=573-673 K(stage Ⅲ)up to 0.15 displacements per atom(dpa)in the Belgian reactor(BR2).The study of the microstructure of neutron-damaged samples using transmission electron microscopy(TEM)revealed visible defects with a predominance of dislocation loops.With an increase in the neutron irradiation temperature,the spatial distribution of the loops acquired pronounced inhomogeneity,and their average size moderately increased.Cavities and voids were not observed.Irradiation-induced hardening was found and a linear correlation was obtained between Vickers microhardness and nanohardness for undamaged and neutron-irradiated CVD-W samples.Irradiation of tungsten with neutrons led to a significant increase in the retention of deuterium,which accumulated mainly in vacancy-type traps.Furthermore,the influence of the columnar grain structure in low-dose neutron-irradiated tungsten seemed to be non-trivial upon deuterium retention.

关键词： CVD-W Neutron irradiation Microstructure Hardening Deuterium retention