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Contribution of winter fluxes to the annual CH_4, CO_2 and N_2O emissions from fres hwater marshes in the Sanjiang Plain

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Journal of Environmental Sciences 2006年第2期18卷 270-275页

作者： HAO Qing-ju WANG Yue-si SONG Chang-chun huang yao Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

Wetlands at the interface of the terrestrial and aquatic ecosystems are intensive sites for mineralization of organic matter, but the contribution of winter season fluxes of CH4, CO2 and N2O from wetland ecosystems to annual budgets is poorly known. By using the static opaque chamber and GC techniques, fluxes of CH4, CO2 and N2O at two freshwater marshes in the Sanjiang Plain were measured during the winter seasons of 2002/2003 and 2003/2004 with contrasting snow conditions and flooding regimes. The results showed that there were significant interannual and spatial differences in CH4, CO2 and N2O fluxes. The Carex lasiocarpa marsh emitted more CH4 and CO2 while absorbed less N2O than the Deyeuxia angustifolia marsh during the winter seasons. Over the winter season, emissions of CH4, CO2 and N2O ranged from 0.42 to 2.41 gC/m^2, from 24.13 to 50.16 gC/m^2, and from -25,20 to -148.96 mgN/m^2, respectively. The contributions of winter season CH4 and CO2 emission to the annual budgets were 2.32% 4.62% and 22.17%- 27.97%, respectively. Marshes uptake N2O during the freezing period, while release N2O during the thawing period. The winter uptake equaled to 13.70%-86.69% of the growing-season loss. We conclude that gas exchange between soil/snow and the atmosphere in the winter season contributed greatly to the annual budgets and cannot be ignored in a cool temperate freshwater marsh in Northeast China.

关键词： freshwater marsh winter flux greenhouse gas emission Sanjiang Plain

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Non-Settlement as Part of Efforts to Build a Community with a Shared Future for Mankind

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Social Sciences in China 2021年第4期42卷 38-54页

作者： huang yao Shao Ya’nan School of Law Sun Yat-sen University the School of Foreign Languages at Tianjin Chengjian University

Studying the scientific connotations of the concept of a community with a shared future for mankind and its guiding significance in international law is an important topic,and integrating the rich ideas contained in this concept into the theory of international dispute settlement is of great practical *** present,the practice of international dispute settlement is encountering many difficulties,and there is a need to create new models and new ideas for international dispute *** non-settlement is an important supplement to the existing methods of international dispute *** and theorizing the practice of peaceful non-settlement from a legal perspective and making the concept of a community with a shared future for mankind a theoretical resource for supporting peaceful non-settlement can help enrich and guide the practice of peaceful *** addition,peaceful non-settlement can help build a community with a shared future for mankind.

关键词： a community with a shared future for mankind international disputes peaceful non-settlement non-settlement international cooperation

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Changes in soil organic carbon of terrestrial ecosystems in China:A mini-review

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Science China(Life Sciences) 2010年第7期53卷 766-775页

作者： huang yao SUN WenJuan ZHANG Wen YU YongQiang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

The present study provides an overview of existing literature on changes in soil organic carbon(SOC) of various terrestrial ecosystems in *** from the literature suggest that SOC stocks in forest,grassland,shrubland and cropland increased between the early 1980s and the early 2000s,amounting to(71±19) Tg·*** of marshland to cropland in the Sanjiang Plain of northeast China resulted in SOC loss of(6±2) Tg·a-1 during the same ***,large uncertainties exist in these estimates,especially for the SOC changes in the forest,shrubland and *** reduce uncertainty,we suggest that future research should focus on:(i) identifying land use changes throughout China with high spatiotemporal resolution,and measuring the SOC loss and sequestration due to land use change;(ii) estimating the changes in SOC of shrubland and non-forest trees(i.e.,cash,shelter and landscape trees);(iii) quantifying the impacts of grassland management on the SOC pool;(iv) evaluating carbon changes in deep soil layers;(v) projecting SOC sequestration potential;and(vi) developing carbon budget models for better estimating the changes in SOC of terrestrial ecosystems in China.

关键词： change China soil organic carbon terrestrial ecosystem uncertainty

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Mapping the vertical distribution of maize roots in China in relation to climate and soil texture

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Journal of Plant Ecology 2018年第6期11卷 899-908页

作者： Sheng Wang yao huang Wenjuan Sun Lingfei Yu State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences20 NanxincunXiangshanBeijing 100093China University of Chinese Academy of Sciences No.19 Yuquan RoadShijingshan DistrictBeijing 100049China

Aims Optimizing water and fertilizer management for crops requires an understanding of root ***(Zea mays L.)is currently the most widely planted cereal crop in China,yet the vertical dis-tribution of maize roots across different regions remains *** aims of this work were(i)to quantify the effects of climate and soil texture on the vertical distribution of maize roots,and(ii)to show the depth distribution of root biomass in *** We used data of maize root biomass from 11 Chinese ecological stations with discontinuous observations from 2004 to 2014 to fit the regression coefficientβfor an asymptotic equation Y=1-βd,where d is the soil depth and Y is the proportion of root biomass from the surface to depth d.A statistical model was then developed to quantify the effects of climate and soil texture on the fittedβ*** the statistical model,we map the depth distribution of maize root biomass in *** Findings Maize root biomass in the 0-100 cm soil depth varied by an order of magnitude at different stations,from 64 to 268 g m−*** planted in sandy soils and/or maize with high accumu-lated temperature for development had higher root biomass and deeper rooting *** fittedβvalues ranged from 0.785 to 0.977,which can be modeled by an integration of the accu-mulated temperature during the maize growing period and the soil clay and sand fractions(R2=0.66,n=50,P<0.001).Up to 82%of maize planting regions in China showed shallower rooting systems where more than 90%and 95%of the root bio-mass occurred in the top 20 and 30 cm soil layers,*** rooting systems occurred in some temperate arid and temperate semi-arid regions,with less than 80%of the root bio-mass in the top 20 cm *** findings highlighted the vertical distribution of maize roots,and underlined the spatial variability in the vertical distribution of roots across China’s planting areas of maize.

关键词： accumulated temperature maize root soil texture statistical model vertical distribution

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A Parzen Window-based Approach to Detection of Infrared Dim Target Under Sea-sky Background

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International Journal of Automation and computing 2016年第5期13卷 447-456页

作者： He Deng huang yao Yan-Tao Wei Ji-Dong Chen Department of Information Technology Central China Normal University Wuhan 430079 China Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430079 China Shaoxing Testing Institute of Quality and Technical Supervision Shaoxing 312071 China

People attach great importance to high detection probability and low false alarm probability for infrared dim target detection. Consequently, a novel approach is proposed based on inverted local information entropy map and the improved region growing technique. The idea originates from the intrinsic property of natural image, the visual mechanism of flying insects and the information entropy theory. Besides qualitative analyses, other methods including the norms of local signal-to-background ratio, local signal-to-noise ratio, region non-uniformity, single-frame detection probability and single-frame false alarm probability are adopted to quantitatively evaluate the proposed approach. Both qualitative and quantitative comparisons confirm the validity and efficiency of the proposed approach.

关键词： Dim target detection information entropy Parzen window region growing visual mechanism.

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Intelligence evolution for service robot： An ADRC perspective

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Control Theory and Technology 2018年第4期16卷 324-335页

作者： Guofei XIANG yao huang Jingrui YU Mingde ZHU Jianbo SU Department of Automation Shanghai Jiao Tong University Shanghai 200240 China

The strategy of active disturbance rejection control （ADRC） and its applications in intelligence evolution for service robot are summarized. It is also shown that the philosophy of ADRC is consistent with the essential characteristics of intelligence evolution. Most importantly, we concentrate on five core issues which will be encountered when applying ADRC to deal with intelligence evolution for service robot, that is, how to eliminate the impact of unknown composite disturbances, how to handle the nonholonomic constraints in uncalibrated visual servoing, how to realize eye-hand-torque coordination, how to deal with the disturbance in simultaneous localization and mapping （SLAM）, and how to reject the imperfections induced by network in human-robot interaction. The main purpose of this paper is to clarify the challenges encountered on intelligence evolution for service robot when one applies ADRC to, hoping that more and more researchers can give some suggestions or work together to deal with these problems, and flourishing results of ADRC from both theory and applications.

关键词： Service robot motion control visual servoing nonholonomic constraints eye-hand-torque coordination simultaneous localization and mapping (SLAM) human-robot interaction (HMI) active disturbance rejection control (ADRC)

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Addition Reaction of Bis(diphenylphosphinyl) Butadiyne with Methylcyclopentadiene

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Chinese Journal of Structural Chemistry 2007年第8期26卷 939-944页

作者： YU Li-Zhi XU Ke-Xin MENG Ji-Ben huang yao-Dong Department of Pharmaceutical Engineering School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China Department of Chemistry Nankai University Tianjin 300071 China

Bis（diphenylphosphinyl）butadiyne reacted with methylcyclopentadiene at room temperature and four isomeric products were obtained. Crystal structures of isomers 1 and 3 have been determined. Crystal data for compound 1 C40H36O2P2·2CHCl3： monoclinic, space group C12/c1 with a = 17.983（2）, b = 11.8723（12）, c = 20.081（2） A, β = 111.218（3）°, V= 3996.5（8） A^3, Z = 4, Mr= 849.36, Dc = 1.412 g/cm^3, F（000） = 1752,μ = 0.546 mm^-1, the final R = 0.0351 and wR = 0.0951 for 3965 observed reflections （I 〉 2σ（I））; and those for compound 3 C40H36O2P2·H2O： triclinic, space group PI with a = 10.4144（15）, b = 13.0558（18）, c = 13.742（2） A, a = 70.453（8）, β = 75.382（8）, γ = 72.312（8）°, V = 1653.7（4） A^3, Z = 2, Mr= 628.64, Dc = 1.262 g/cm^3, F（000） = 664,μ = 0.169 mm^-1, the final R = 0.0593 and wR = 0.1296 for 4891 observed reflections （I 〉 2σ（I））. The structures of the other two isomers are identified via IR, ^1H NMR and MS spectra.

关键词： addition reaction crystal structure inclusion hydrogen bonding

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Lithium Storage Property of Graphite/AlCuFe Quasicrystal Composites

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Chinese Physics Letters 2019年第9期36卷 77-81页

作者： Haijuan Wang Xiao Lan yao huang Xunyong Jiang Key Laboratory of Display Materials and Photoelectric Devices(Ministry of Ed ucation) Tianjin Key Laboratory for Photoelectric Materials and DevicesNational Demonstration Genter for Experimental Function Materialsand School of Materials Science and EngineeringTianjin University of TechnologyTianjin 300191

Quasicrystals have long-range quasi-periodic translational ordering and non-crystallographic rotational ***-Cu-Fe quasicrystals have great potential for lithium storage because of their high Al content and a large number of defects in the *** our previous study(*** Compd.805(2019)942)we showed that Al-Cu-Fe quasicrystals have good initial capacity whereas its cycle stability is *** the present study,graphite/AlCuFe is prepared by the mechanical alloying *** results show that graphite/AlCuFe quasicrystal composites are successfully synthesized by planetary ball milling at 550 rpm for 80 *** quasicrystal particle size decreases and the amorphous graphite forms onion-like carbon(OLC)when the two phases mix *** forms on the surface of the Al-Cu-Fe quasicrystalline *** and discharge tests show that graphite/AlCuFe quasicrystal composites have high-stability capacity of 480 mAh/g after 20 cycles,which is larger than the sum of capacities of graphite and Al-Cu-Fe quasicrystals.

关键词： Cu pro cycle Lithium Storage Property of Graphite/AlCuFe Quasicrystal Composites Graphite

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Simulation study of energy resolution with changing pixel size for radon monitor based on Topmetal-Ⅱ^- TPC

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Nuclear Science and Techniques 2019年第1期30卷 49-57页

作者： Meng-yao huang Hua Pei Xiang-Ming Sun Shu-Guang Zou Department of Physics and Astronomy Iowa State University PLAC Key Laboratory of Quark & Lepton Physics (MOE)Central China Normal University College of Information Science and Engineering Henan University of Technology

In this paper, we study how pixel size influences energy resolution for a proposed pixelated detector—a high sensitivity, low cost, and real-time radon monitor based on a Topmetal-Ⅱ^- time projection chamber(TPC). This monitor was designed to improve spatial resolution for detecting radon alpha particles using Topmetal-Ⅱ^- sensors assembled by a 0.35 lm CMOS integrated circuit *** to concerns that small pixel size might have the side effect of worsening energy resolution due to lower signalto-noise ratio, a Geant4-based simulation was used to investigate the dependence of energy resolution on pixel sizes ranging from 60 to 600 lm. A non-monotonic trend in this region shows the combined effect of pixel size and threshold on pixels, analyzed by introducing an empirical expression. Pixel noise contributes 50 keV full-width at half-maximum energy resolution for 400 lm pixel size at 1–4σ threshold that is comparable to the energy resolution caused by energy fluctuations in the TPC ionization process( ~20 keV). The total energy resolution after combining both factors is estimated to be 54 keV for a pixel size of 400 lm at 1–4σ threshold. The analysis presented in this paper would help choosing suitable pixel size for future pixelated detectors.

关键词： Geant4 Energy resolution Pixel size Radon monitor Topmetal

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Soil Carbon Sequestration Potential as Affected by Management Practices in Northern China:A Simulation Study

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Pedosphere 2014年第4期24卷 529-543页

作者： WANG Guo-Cheng WANG En-Li huang yao XU Jing-Jing State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of Sciences CSIRO Land & Water Black MountainCanberraACT 2601(Australia) State Key Laboratory of Vegetation and Environmental Change(LVEC) Institute of BotanyChinese Academy of Sciences

Soil has been identified as a possible carbon （C） sink for sequestering atmospheric carbon dioxide （CO2）. However, soil organic carbon （SOC） dynamics in agro-ecosystems is affected by complex interactions of various factors including climate, soil and agricultural management practices, which hinders our understanding of the underlying mechanisms. The objectives of this study were to use the Agricultural Production Systems simulator （APSIM） model to simulate the long-term SOC dynamics under different management practices at four long-term experimental sites, Zhengzhou and Xuzhou with double cropping systems and Gongzhuling and Urtimqi with single cropping systems, located in northern China. Firstly, the model was calibrated using information from the sites and literature, and its performance to predict crop growth and SOC dynamics was examined. The calibrated model was then used to assess the impacts of different management practices, including fertilizer application, irrigation, and residue retention, on C dynamics in the top 30 cm of the soil by scenario modelling. Results indicate a significant SOC sequestration potential through improved management practices of nitrogen （N） fertilizer application, stubble retention, and irrigation. Optimal N fertilization （Nopt） and 100% stubble retention （R100） increased SOC by about 11.2%, 208.29%, and 283.67% under irrigation at Gongzhuling, Zhengzhou, and Xuzhou, respectively. Soil organic carbon decreased rapidly at lJriimqi under irrigation, which was due to the enhanced decomposition by increased soil moisture. Under rainfed condition, SOC remained at a higher level. The combination of Nopt and R100 increased SOC by about 0.46% under rainfed condition at /Jr/imqi. Generally, agricultural soils with double cropping systems （Zhengzhou and Xuzhou） showed a greater potential to sequester C than those with single cropping systems （Gongzhuling and Urumqi）.

关键词： agro-ecosystems APSIM model fertilizer application irrigation residue retention scenario analysis soil organic carbon

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