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Journal of Environmental Sciences 2014年第11期26卷 2283-2289页

作者： Chen Gong xiaomin sun Chenxi Zhang Jingtian Hu Chuansong Qi Environment Research Institute Shandong University College of Chemical Engineering Beijing Institute of Petrochemical Technology

Dielectric barrier discharges （DBD） have been used in the degradation of dioxins due to the large number of excimers and free radicals produced in discharge process. In this article, the density functional theory （DFT） is used to study the degradation mechanism of octachlorinated dibenzo-p-dioxin （OCDD） with the atomic oxygen O（3P） in DBD reactor. The reactants, intermediates, transition states and products are optimized at the MPWB1K/6- 31 ＋ G（d,p） level. The vibrational frequencies have been calculated at the same level. The reaction pathways and mechanisms are analyzed in detail. The effect of removing the chlorine atom on environment also has been discussed.

关键词： OCDD Dechlorination reaction Dielectric barrier discharge Atomic oxygen

Nitrate in shallow groundwater in typical agricultural and forest ecosystems in China,2004-2010

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Journal of Environmental Sciences 2013年第5期25卷 1007-1014页

作者： Xinyu Zhang Zhiwei Xu xiaomin sun Wenyi Dong Deborah Ballantine Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences National Institute of Water and Atmospheric Research HamiltonNew Zealand

The nitrate-nitrogen（NO 3-N） concentrations from shallow groundwater wells situated in 29 of the Chinese Ecosystem Research Network field stations,representing typical agroand forest ecosystems,were assessed using monitoring data collected between 2004 and *** from this assessment permit a national scale assessment of nitrate concentrations in shallow groundwater,and allow linkages between nitrate concentrations in groundwater and broad land use categories to be *** indicated that most of the NO 3--N concentrations in groundwater from the agroand forest ecosystems were below the Class 3 drinking water standard stated in the Chinese National Standard：Quality Standard for Ground Water（≤ 20 mg/L）.Over the study period,the average NO 3--N concentrations were significantly higher in agro-ecosystems（4.1 ± 0.33 mg/L） than in forest ecosystems（0.5 ± 0.04 mg/L）.NO 3-N concentrations were relatively higher（〉 10 mg N /L） in 10 of the 43 wells sampled in the agricultural *** elevated concentrations occurred mainly in the Ansai,Yucheng,Linze,Fukang,Akesu,and Cele field sites,which were located in arid and semiarid areas where irrigation rates are *** suggest that improvements in N fertilizer application and irrigation management practices in the arid and semi-arid agricultural ecosystems of China are the key to managing groundwater nitrate concentrations.

关键词： Chinese Ecosystem Research Network shallow groundwater agricultural forest ecosystems nitrate concentration

Ozone concentrations, flux and potential effect on yield during wheat growth in the NorthwestShandong Plain of China

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Journal of Environmental Sciences 2015年第8期27卷 1-9页

作者： Zhilin Zhu xiaomin sun Fenghua Zhao Franz X.Meixner Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences Biogeochemistry Department Max-Planck-Institute for Chemistry

Ozone（O3） concentration and flux（Fo） were measured using the eddy covariance technique over a wheat field in the Northwest-Shandong Plain of China. The O3-induced wheat yield loss was estimated by utilizing O3exposure-response models. The results showed that：（1） During the growing season（7 March to 7 June, 2012）, the minimum（16.1 ppb V） and maximum（53.3 ppb V）mean O3 concentrations occurred at approximately 6：30 and 16：00, respectively. The mean and maximum of all measured O3 concentrations were 31.3 and 128.4 ppb V, respectively. The variation of O3 concentration was mainly affected by solar radiation and temperature.（2） The mean diurnal variation of deposition velocity（V d） can be divided into four phases, and the maximum occurred at noon（12：00）. Averaged V d during daytime（6：00–18：00） and nighttime（18：00–6：00） were 0.42 and 0.14 cm/sec, respectively. The maximum of measured V d was about1.5 cm/sec. The magnitude of V d was influenced by the wheat growing stage, and its variation was significantly correlated with both global radiation and friction velocity.（3） The maximum mean F o appeared at 14：00, and the maximum measured F o was-33.5 nmol/（m^2·sec）. Averaged F o during daytime and nighttime were-6.9 and-1.5 nmol/（m^2·sec）, respectively.（4） Using O3 exposure-response functions obtained from the USA, Europe, and China, the O3-induced wheat yield reduction in the district was estimated as 12.9% on average（5.5%–23.3%）. Large uncertainties were related to the statistical methods and environmental conditions involved in deriving the exposure-response functions.

关键词： Ozone concentration Ozone flux Deposition velocity Eddy covariance Yield loss estimation Cropland ecosystem

Mechanism and kinetics study on the ozonolysis reaction of 2,3,7,8-TCDD in the atmosphere

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Journal of Environmental Sciences 2014年第1期26卷 181-188页

作者： Jing Bai xiaomin sun Chenxi Zhang Chen Gong Jingtian Hu Jianghua Zhang Environment Research Institute Shandong University School of Management Shandong University

The ozonolysis of 2,3,7,8-tetra-chlorodibenzo-p-dioxin （2,3,7,8-TCDD） is an efficient degradation way in the atmosphere. The ozonolysis process and possible reactions path of Criegee Intermediates with NO and H2O are introduced in detail at the method of MPWB1K/6-31＋G（d,p）//MPWB1K/6- 311＋G（3df,2p） level. In ozonolysis, H2O is an important source of OH radical formation and initiated the subsequent degradation reaction. The Rice-Ramsperger-Kassel-Marcus （RRKM） theory was applied to calculate rate constants with the temperature ranging from 200 to 600 K. The rate constant of reaction between 2,3,7,8-TCDD and 03 is 4.80 × 10^-20 cm3/（***） at 298 K and 760 Tort. The atmospheric lifetime of the reaction species was estimated according to rate constants, which is helpful for the atmospheric model study on the degradation and risk assessment of dioxin.

关键词： ozonolysis reaction of 2 3 7 8-TCDD chemical mechanism and kinetics study rate constants atmospheric lifetime

基于“岗课赛证”融通高职老年保健与管理人才培养改革的探究

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卫生职业教育 2025年第1期43卷 16-19页

作者：孙晓敏刘昕范小琳顾磊南京卫生高等职业技术学校江苏南京210000 南京医科大学附属肿瘤医院江苏南京210000

针对高职院校“岗课赛证”融通实践中融通深度不足、教学模式单一和实训条件有限等问题进行改进,遵循校企深度合作、双主体育人的设计思路,构建以岗定标、以赛促教、以证融课、以课定学的课程体系,以典型工作任务为驱动的“三阶五步”... 详细信息

针对高职院校“岗课赛证”融通实践中融通深度不足、教学模式单一和实训条件有限等问题进行改进,遵循校企深度合作、双主体育人的设计思路,构建以岗定标、以赛促教、以证融课、以课定学的课程体系,以典型工作任务为驱动的“三阶五步”教学模式,为学生增值赋能的多元多维评价体系,遵循“双向奔赴,共创精彩”的课程思政理念,以提高学生综合职业能力,培养高素质复合型技术技能型老年保健与管理人才。

关键词：岗课赛证高职老年保健与管理校企合作

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The Limiting Effect of Deep Soil Water on Evapotranspiration of a Subtropical Coniferous Plantation Subjected to Seasonal Drought

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Advances in Atmospheric Sciences 2014年第2期31卷 385-395页

作者： TANG Yakun WEN Xuefa sun xiaomin ZHANG Xinyu WANG Huimin Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences

Seasonal drought is a common occurrence in humid *** year 2003 was the driest year during the period 1985-2011 in southeastern *** objective of this study was to elucidate the impact of the exceptional drought in 2003,compared with eddy flux measurements during 2004-11,on the dynamics of evapotranspiration （ET） and related factors,as well as their underlying mechanisms,in a subtropical coniferous plantation in southeastern *** was found that daily ET decreased from 5.34 to 1.84 mm during the intensive drought period and recovered to 4.80 mm during the subsquent recovering drought *** analysis indicated that ET was mainly determined by canopy conductance and deep soil water content （50 cm） during the intensive drought and recovering drought periods,*** canopy conductance offset the positive effect of air vapor pressure deficit on ET when suffering drought stress,while the canopy conductance enhanced the positive effect of air temperature on ET during the late growing *** the fine roots of this plantation are mainly distributed in shallow soil,and the soil water in the upper 40 cm did not satisfy the demand for ET,stomatal closure and defoliation were evident as physiological responses to drought stress.

关键词： ChinaFLUX evapotranspiration seasonal drought subtropical coniferous plantation

A Hybrid Multi-Objective Evolutionary Algorithm for Optimal Groundwater Management under Variable Density Conditions

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Acta Geologica Sinica(English Edition) 2012年第1期86卷 246-255页

作者： YANG Yun WU Jianfeng sun xiaomin LIN Jin WU Jichun Department of Hydrosciences School of Earth Sciences and EngineeringNanjing UniversityNanjingJiangsu 210093China Nanfing Hydraulic Research Institute NanjingJiangsu 210029China

In this paper, a new hybrid multi-objective evolutionary algorithm （MOEA）, the niched Pareto tabu search combined with a genetic algorithm （NPTSGA）, is proposed for the management of groundwater resources under variable density conditions. Relatively few MOEAs can possess global search ability contenting with intensified search in a local area. Moreover, the overall searching ability of tabu search （TS） based MOEAs is very sensitive to the neighborhood step size. The NPTSGA is developed on the thought of integrating the genetic algorithm （GA） with a TS based MOEA, the niched Pareto tabu search （NPTS）, which helps to alleviate both of the above difficulties. Here, the global search ability of the NPTS is improved by the diversification of candidate solutions arising from the evolving genetic algorithm population. Furthermore, the proposed methodology coupled with a density-dependent groundwater flow and solute transport simulator, SEAWAT, is developed and its performance is evaluated through a synthetic seawater intrusion management problem. Optimization results indicate that the NPTSGA offers a tradeoff between the two conflicting objectives. A key conclusion of this study is that the NPTSGA keeps the balance between the intensification of nondomination and the diversification of near Pareto-optimal solutions along the tradeoff curves and is a stable and robust method for implementing the multi-objective design of variable-density groundwater resources.

关键词： seawater intrusion multi-objective optimization niched Pareto tabu search combined with genetic algorithm niched Pareto tabu search genetic algorithm

On the applicability of Kirchoff's law and the principle of heat balance in thermal infrared remote sensing:A non-isothermal system

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Science China Earth Sciences 2005年第1期48卷 53-64页

作者： ZHANG Renhua LI Zhaoliang sun xiaomin ZHU Zhilin WANG Weimin Institute of Geographical Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

This paper proposes a basic equation of thermal radiation interaction between surface objects on the basis of the principle of heat balance in the interface. The solution of this equation takes account of the contribution of sensible heat flux and latent heat flux more completely, compared with traditional solution for surface cooling and heating processes. By the aid of the experimental data conducted in the Xiaotangshan experimental site, Beijing, both the non-applicability of Kirchoff's law and the measurability of surface emissivity in a non-isothermal system have been highlighted. Two methods called ventilation and time-delay compensations have been proposed to reduce the error induced by change of surface temperatures of non-isothermal objects during the measurement of emissivity. Based on the solution of the basic equation, this paper has analyzed and pointed out the misunderstanding in comprehension and application of Kirchoff's law published in literature.

关键词： applicability of Kirchoff's law, heat balance, non-isothermal system.

Duple-EDA and sample density balancing

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Science in China(Series F) 2009年第9期52卷 1640-1650页

作者： CAI YunPeng XU Hua sun xiaomin JIA PeiFa LIU ZeHua State Key Laboratory on Intelligent Technology and Systems Tsinghua National Laboratory for Information Science and Technology Department of Computer Science and Technology Tsinghua University Beijing 100084 China School of Computer Engineering Nanyang Technological University Singapore 639798 Singapore

In this paper, a new method is proposed to overcome the problem of local optima traps in a class of evolutionary algorithms, called estimation of distribution algorithms （EDAs）, in real-valued function optimization. The Duple-EDA framework is proposed in which not only the current best solutions but also the search history are modeled, so that long-term feedback can be taken into account. Sample Density Balancing （SDB） is proposed under the framework to alleviate the drift phenomenon in EDA. A selection scheme based on Pareto ranking considering both the fitness and the historical sample density is adopted, which prevents the algorithm from repeatedly sampling in a small region and directs it to explore potentially optimal regions, thus helps it avoid being stuck into local optima. An MBOA （mixed Bayesian optimization algorithm） version of the framework is implemented and tested on several benchmark problems. Experimental results show that the proposed method outperforms a standard niching method in these benchmark problems.

关键词： evolutionary computation estimation of distribution algorithm Boltzmann selection

Specific Responses of Soil Microbial Residue Carbon to Long-Term Mineral Fertilizer Applications to Reddish Paddy Soils

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Pedosphere 2018年第3期28卷 488-496页

作者： ZHANG Xinyu XIE Juan YANG Fengting DONG Wenyi DAI Xiaoqin YANG Yang sun xiaomin Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences Beijing 100101( China) College of Resources and Environment University of Chinese Academy of Sciences Beijing 100190( China) Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences Beijing 100081(China)

Mineral nutrient inputs to soil may alter microbial activity and consequently influence the accumulation of microbial residues. In this study, we investigated the effects of application rates and ratios of mineral fertilizers on the microbial residue carbon(MRC) of reddish paddy soils after long-term(15-year) fertilizer applications in southern China. Contents of three soil amino sugars as microbial residue contents were determined and MRC were calculated based on amino sugars. Results showed that three individual amino sugar contents increased as fertilizer application rates increased until maximum values were reached at a rate of 450-59-187 kg ha^(-1) year^(-1)(N-P-K). The three amino sugar contents then declined significantly under the highest mineral fertilizer application rate of 675-88-280 kg ha^(-1) year^(-1)(N-P-K). In addition, to enhance the microbial residue contents, it was more beneficial to double P(N:P:K= 1:0.26:0.41) in fertilizers applied to the P-deficient reddish paddy soils than to double either N(N:P:K = 2:0.13:0.41) or K(N:P:K= 1:0.13:0.82). The contents of the three individual amino sugars and microbial residues under different fertilizer application rates and ratios were significantly and positively correlated with soil organic carbon(SOC), total N, total P, and p H. Increases in values of the fungal C to bacterial C ratios showed that soil organic matter(SOM) stability increased because of the fertilizer applications over the past 15 years. The contents and ratios of amino sugars can be used as indicators to evaluate the impact of mineral fertilizer applications on SOM dynamics in subtropical paddy soils. The results indicated that fertilizer applications at a rate of 450-59-187 kg ha^(-1) year^(-1)(N-P-K) may improve crop yields, SOC contents, and SOC stability in subtropical paddy soils.

关键词： amino sugar application rate application ratio bacterial C fungal C soil nutrient soil organic C