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Journal of Arid Land 2023年第2期15卷 218-230页

作者： SUN Mengjie GUO Shiwen XIONG Chunlian li pinfang College of Land Science and Technology China Agricultural UniversityBeijing 100193China College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China Yibin Ecological Environment Monitoring Center Sichuan 644099China

Since Pb is a non-biodegradable inorganic pollutant and a non-essential metal,its long-term presence in soil poses a great threat to the *** lactea ***(Fisch.)Koidz.,a perennial dense bush herb with high resistance of Pb and wide adaptability,was used in pot experiments to study the effects of exogenous nitrate N(NO_(3)^(–)-N)on the absorption and transportation of Pb and plant growth under different Pb ***,the mechanism of NO_(3)^(-)-N affecting Pb and nutrient uptake and transport was *** concentration of Pb in the experiment ranged from 0 to 1600 mg/kg,and the added concentration of NO_(3)^(-)-N was 0.0–0.3 g/*** results showed that *** was highly tolerant to Pb,and the shoot fraction was more sensitive to varied Pb concentrations in the soil than the root *** protective function became more pronounced under the condition of raised Pb concentration in the *** the concentration of Pb in the soil reached 800 mg/kg,the highest Pb content of *** was found under the condition of 0.1 g/kg of NO–3-N *** Pb concentration in the soil increased to 1600 mg/kg,the increase in NO_(3)^(-)-N addition promoted Pb uptake by the *** ensure the well growth of *** and the effect of remediation of Pb-contaminated soil,the recommended concentration of NO–3-N in the soil is 0.1 g/*** result provides a theoretical basis for exogenous N regulation of phytoremediation of Pb-contaminated soil.

关键词： Iris lactea nitrate nitrogen plant nutrient lead accumulation absorb transport

K^(+)and Na^(+)fluxes in roots of two Chinese Iris populations

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Frontiers of Agricultural Science and Engineering 2014年第2期1卷 144-149页

作者： pinfang li Biao ZHANG Key Laboratory of Arable Land Conservation(North China)of Ministry of Agriculture Key Laboratory of Plant-Soil Interactions of Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China College of Resources and Environmental Sciences Henan Agricultural UniversityZhengzhou 450002China

Maintenance of ion homeostasis,particularly the regulation of K^(+)and Na^(+)uptake,is important for all plants to adapt to *** on ionic response to salinity and net fluxes of K^(+),Na^(+)in the root exhibited by plants during salt stress have highlighted the need for further *** objectives of this study were to compare salt adaptation of two Chinese Iris(Iris lactea ***(Fisch.)Koidz.)populations,and to improve understanding of adaptation to salinity exhibited by *** used in this study were grown from seeds collected in the Xinjiang Uygur Autonomous Region(Xj)and Beijing Municipality(Bj),*** seedlings of the two populations were supplied with nutrient solutions containing 0.1(control)and 140 mmol·L^(–1) *** 12 days,plants were harvested for determination of relative growth rate and K^(+),Na^(+)*** fluxes of K^(+),Na^(+)from the apex and along the root axis to 10.8 mm were measured using noninvasive micro-test *** 140 mmol·L^(–1) NaCl treatment,shoots for population Xj had larger relative growth rate and higher K^(+)concentration than shoots for population ***,the Na^(+)concentrations in both shoots and roots were lower for Xj than those for *** was a lower net efflux of K^(+)found in population Xj than by Bj in the mature zone(approximately 2.4^(–1)0.8 mm from root tip).However,no difference in the efflux of Na^(+)between the populations was *** Xj of *** continued to grow normally under NaCl stress,and maintained a higher K^(+)/Na^(+)ratio in the *** traits,which were associated with lower K^(+)leakage,help population Xj adapt to saline environments.

关键词： Iris lactea Pall.var.chinensis(Fisch.)Koidz population K+and Na+ ion flux non-invasive micro-test technique

基于一次回归正交设计的船舶柴油机掺烧丁醇性能优化

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船舶工程 2024年第2期46卷 73-81页

作者：杨晨曦才正黄朝霞范金宇李品芳黄加亮集美大学轮机工程学院福建厦门361021 集美大学理学院福建厦门361021 福建省船舶与海洋工程重点实验室福建厦门361021

为优化丁醇-柴油双燃料发动机的性能,以4190ZLC-2型船用中速柴油机为原型,利用AVL-FIRE仿真软件建立双燃料发动机高压循环模型,并通过原机验证模型的准确性。在确定丁醇掺混比例为20%后,运用一次回归正交试验设计方法对燃油系统5个参数... 详细信息

为优化丁醇-柴油双燃料发动机的性能,以4190ZLC-2型船用中速柴油机为原型,利用AVL-FIRE仿真软件建立双燃料发动机高压循环模型,并通过原机验证模型的准确性。在确定丁醇掺混比例为20%后,运用一次回归正交试验设计方法对燃油系统5个参数进行优化,找出指示功率最大值和NOx排放量最小值的参数组合。结果表明:建立的指示功率、NOx排放量预测模型的准确度较高,可用于参数优化匹配研究;指示功率最大参数组合为废气再循环率0%、进气压力0.233MPa、进气温度325.15 K、喷油提前角22.6°CA、喷油孔直径0.26 mm;NO排放量最低参数组合为废气再循环率12.5%、进气压力0.173 MPa、进气温度355.15 K、喷油提前角16.6°CA、喷油孔直径0.32 mm;相较于原机,优化后的指示功率和NOx排放量分别提升7.4%和降低98.3%。

关键词：双燃料发动机一次回归正交 NOx排放量指示功率丁醇

杭锦旗黄河南岸灌区土壤质量指数计算方法比较研究

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中国农业大学学报 2024年第4期29卷 251-263页

作者：周文涛潘岳乔冠宇朱金籴佟长福王贵平杨智李品芳中国农业大学土地科学与技术学院北京100193 开封市农林科学研究院河南开封475004 水利部牧区水利科学研究所呼和浩特010020 杭锦旗黄河灌排服务中心内蒙古鄂尔多斯017400

为研究土壤质量评价过程中不同质量指数计算方法的差异与最优组合,采集并测定了内蒙古杭锦旗黄河南岸灌区79个土壤样本的11项理化指标,并基于主成分分析法构建最小数据集,对比分析了主成分分析法和层次分析法2种权重确定方法与隶属度函... 详细信息

为研究土壤质量评价过程中不同质量指数计算方法的差异与最优组合,采集并测定了内蒙古杭锦旗黄河南岸灌区79个土壤样本的11项理化指标,并基于主成分分析法构建最小数据集,对比分析了主成分分析法和层次分析法2种权重确定方法与隶属度函数、线性评分函数和非线性评分函数3种指标评分方法组合下计算的土壤质量指数,最后通过与全体数据集的自相关精度检验获取最优方法组合。结果表明:1)层次分析法确定的物理指标权重高于主成分分析法,速效养分指标权重低于主成分分析法,隶属度函数、线性评分函数、非线性评分函数对指标分值计算结果的分布趋势基本保持一致,但隶属度函数对物理指标进行评分时具有更高的区分度;2)采用层次分析法确定指标权重,隶属度函数确定指标分值计算的最小数据集土壤质量指数的自相关检验精度最高(R^(2)=0.85),纳什效率系数为0.81,相对偏差系数为0.04;3)最优方法组合下全体数据集和最小数据集的土壤质量指数变化分别是0.25~0.71和0.16~0.78,平均值为0.43和0.45,表明研究区域土壤处于中等质量水平。综上,本研究确定了准确评价杭锦旗黄河南岸灌区土壤质量的最优方法组合,可为今后土壤质量评价研究中指标权重和分值计算方法的选择提供参考。

关键词：土壤质量指数主成分分析法层次分析法最小数据集黄河南岸灌区

Water adaptive traits of deep-rooted C_3 halophyte(Karelinia caspica(Pall.) Less.) and shallow-rooted C_4 halophyte(Atriplex tatarica L.) in an arid region,Northwest China

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Journal of Arid Land 2012年第4期4卷 469-478页

作者： Yuan FAN pinfang li ZhenAn HOU TuSheng REN Chunlian XIONG Biao ZHANG College of Resources and Environmental Science China Agricultural University Beijing 100193 China Department of Resources and Environmental Science Shihezi University Shihezi 832000 China

This paper focused on the water relations of two halophytes differing in photosynthetic pathway, phe- notype, and life cycle： Karelinia caspica （Pall.） Less. （C3, deep-rooted perennial Asteraceae grass） and Atriplex tatarica L. （C4, shallow-rooted annual Chenopodiaceae grass）. Gas exchange, leaf water potential, and growth characteristics were investigated in two growing seasons in an arid area of Xinjiang to explore the physiological adaptability of the two halophytes. Both K. caspica and A. tatarica showed midday depression of transpiration, in- dicating that they were strong xerophytes and weak midday depression types. The roots of A. tatarica were con- centrated mainly in the 0-60 cm soil layer, and the leaf water potential （~L） increased sharply in the 0-20 cm layer due to high soil water content, suggesting that the upper soil was the main water source. On the other hand, K. caspica had a rooting depth of about 1.5 m and a larger root/shoot ratio, which confirmed that this species uptakes water mainly from deeper soil layer. Although A. tatarica had lower transpiration water consumption, higher water use efficiency （WUE）, and less water demand at the same leaf water potential, it showed larger water stress impact than K. caspica, indicating that the growth of A. tatarica was restricted more than that of K. caspica when there was no rainfall recharge. As a shallow-rooted C4 species, A. tatarica displayed lower stomatal conductance, which could to some extent reduce transpiration water loss and maintain leaf water potential steadily. In contrast, the deep-rooted C3 species K. caspica had a larger root/shoot ratio that was in favor of exploiting groundwater. We concluded that C3 species （K. caspica） tapes water and C4 species （A. tatarica） reduces water loss to survive in the arid and saline conditions. The results provided a case for the phenotype theory of Schwinning and Ehleringer on halophytic plants.

关键词： Karelinia caspica Atriplex tatarica root/shoot ratio leaf water potential stomatal conductance transpiration

掺烧不同比例的异戊醇对船舶柴油机性能的影响

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集美大学学报（自然科学版） 2024年第1期29卷 47-53页

作者：林航王奇伟陈美谦李品芳范金宇黄加亮集美大学轮机工程学院福建厦门361021 泉州海洋职业学院福建泉州362700 福建省船舶与海洋工程重点实验室福建厦门361021

为了研究不同比例的异戊醇/柴油混合燃料在4190Z L C-2型船用中速柴油机中的燃烧和排放特性,运用AVL_FIRE仿真软件建立柴油机燃烧室模型,并通过台架实验验证其仿真模型的准确性。在仿真软件中通过调整异戊醇在柴油中的掺混比来研究混合... 详细信息

为了研究不同比例的异戊醇/柴油混合燃料在4190Z L C-2型船用中速柴油机中的燃烧和排放特性,运用AVL_FIRE仿真软件建立柴油机燃烧室模型,并通过台架实验验证其仿真模型的准确性。在仿真软件中通过调整异戊醇在柴油中的掺混比来研究混合燃料对柴油机燃烧和排放性能的影响。结果表明:掺混异戊醇有助于改变NO的生成规律,使NO在速燃期的生成量上升,在缓燃期与后燃期的生成量减少,并且总体生成的NO质量分数降低;随着异戊醇掺混比的上升,CO最终生成质量分数下降,Soot最终生成质量分数上升,同时生成的Soot质量分数峰值降低,在缓燃期的氧化速率增快,并因为较快的耗氧量使得最终生成的Soot质量分数比纯柴油的高。

关键词：船舶柴油机异戊醇燃烧性能排放性能 AVL-FIRE仿真软件

利用SE-GPR模型对甲醇/柴油混合燃料柴油机性能的预测

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集美大学学报（自然科学版） 2024年第2期29卷 152-161页

作者：范金宇才正黄朝霞杨晨曦李品芳黄加亮集美大学轮机工程学院福建厦门361021 福建省船舶与海洋工程重点实验室福建厦门361021 集美大学理学院福建厦门361021

为了对柴油机的经济性和排放参数进行高效、准确的预测,根据4190型船用柴油机实验数据与边界参数,建立AVL-BOOST甲醇/柴油混合燃料柴油机仿真模型;利用模型进行仿真实验,并建立甲醇掺混比、废气再循环(exhaust gas recirculation,EGR)... 详细信息

为了对柴油机的经济性和排放参数进行高效、准确的预测,根据4190型船用柴油机实验数据与边界参数,建立AVL-BOOST甲醇/柴油混合燃料柴油机仿真模型;利用模型进行仿真实验,并建立甲醇掺混比、废气再循环(exhaust gas recirculation,EGR)率、喷油提前角和进气压力4个控制参数对有效油耗率和NO x排放预测数据集;利用该数据集对5种不同核函数的高斯过程回归(Gaussian process regression,GPR)模型进行训练;最后将最优的平方指数高斯过程回归(squared exponential-Gaussian process regression,SE-GPR)模型、AVL-BOOST仿真数据和柴油机实验数据进行对比。结果表明:在数据量为180组时,SE-GPR模型对有效油耗率和NO x排放均取得拟合关联度99%以上,均方根误差(root mean square error,RMSE)分别为1.859,0.3445,平均绝对误差(mean absolute error,MAE)分别为0.954,0.2489;并且,相较于AVL-BOOST仿真实验,SE-GPR模型对实验数据具有更好的拟合性。

关键词：船用柴油机甲醇高斯过程回归平方指数核函数性能预测

The Distribution Features of Calcic Horizon in Inner Mongolia, China

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The Distribution Features of Calcic Horizon in Inner Mongoli...

基于COMSOL的低渗性盐土内设砂柱洗盐定量模拟

2011 International Conference on Agricultural and NaturalResources Engineering (ANRE 2011)

作者： li pinfang Bai Haifeng A.Egrinya Eneji College of Resources and Environmental Sciences China Agricultural University Department of Soil Science University of Calabar

In the arid and semiarid region, calcic horizons widely exist in the soil profilesThe Arid Agriculture Experimental Station（AAES） of Wu Chuan is located in the arid and semiarid region of Inner Mongolia of China, where calcic horizon are the main obstacle horizonsIn order to understand the distributions features of calcic horizon, we chose a plot of 700 m × 900 m in the AAES to serve as our study area, and 80 soil profiles were undertakenWe determined the depths and thicknesses of calcic horizons, and measured soil texturesThe study indicates that calcic horizons were shallow and thick in the parts with high elevationThe depths of calcic horizons were 30-100 cm, and the thicknesses were mostly 20-40 cmThe more there were sand fractions, and the less there were clay and silt fractions, the deeper and thinner calcic horizons wereUsually, there is higher clay fraction in the calcic horizonThese research findings will help to further understanding the association of elevation and soil texture with the distribution features of calcic horizon.

关键词： Calcic horizon Ca CO3 contents Soil texture

来源： cnki会议评论

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农业机械学报 2014年第7期45卷 111-117,124页

作者：孙雪雁李品芳李保国薛元霞邵蕾中国农业大学农业部华北耕地保育重点实验室北京100193 中国农业大学烟台研究院烟台264670

滨海粘壤质盐土具有质地黏重、渗透性差等特点,工程实践中一种有效的措施是在其土体中建构砂性土柱(简称砂柱)加速其脱盐。针对此工程措施,基于2-D土壤溶质运移模型,应用COMSOL软件模拟了饱和淋洗条件下3种类型砂柱设置的排盐效果,并进... 详细信息

滨海粘壤质盐土具有质地黏重、渗透性差等特点,工程实践中一种有效的措施是在其土体中建构砂性土柱(简称砂柱)加速其脱盐。针对此工程措施,基于2-D土壤溶质运移模型,应用COMSOL软件模拟了饱和淋洗条件下3种类型砂柱设置的排盐效果,并进行了定量分析。结果表明:内设中竖砂柱、单斜对角砂柱和双斜'X'型长砂柱,经过24h淋洗后,其淋洗效率分别是不设砂柱的1.24、1.29和1.45倍;95%盐分的淋出时长分别为不设砂柱的0.88、0.83和0.78倍。这说明内设砂柱能显著提高脱盐效率,不同砂柱构建对脱盐效率也有显著影响,3种砂柱相比,内设双斜'X'型长砂柱的构型最有利于盐分的淋洗,也最节省水资源。

关键词：滨海盐土溶质运移 COMSOL 2-D砂柱数学模拟

Additives strategies to improving cycling stability of li metal batteries by modifying electrode electrolyte interphases

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Progress in Natural Science:Materials International 2024年第2期34卷 338-344页

作者： Yuan li Pengfei Huang Chunyu Cui Xiaoyuan Ma li Chen Zekun li linhai li Yuhong Tian School of Biological and Chemical Engineering Guangxi University of Science and Technology School of College of Chemistry and Chemical Engineering Hunan University Isky Future Energy Institute

li metal batteries（LMBs） have attracted much attention due to the ultra-high theoretical capacity of the li metal anode（LMA）.However,the uncontrollable dendrites growth and low coulombic efficiency hinder their practical ***,we explore 3,5-difluoropyridine（2F-BD） as a novel electrolyte additive to enable highperformance *** 2F-BD additive participates in and modifies the solvation structure of li ions by reducing the coordinated number of PF6-at the electrode surface,leading to the formation of a liF and li3N-rich solid electrolyte interphase（SEI）.The liF component increases the robustness of SEI and suppresses the formation of li dendrites,while the li3N component facilitates the transportation and reaction kinetics of li *** a result,the li‖li symmetric cell presents a stable cycling performance of up to 500 h at a current density of 1 mA *** coupling with liFePO4cathode,the obtained full cell achieves high specific capacities of 106.06 mA h g-1and 84.98 mA h g-1at 2.55 mA cm-2and 5.10 mA cm-2,respectively,and maintains a high capacity retention of84.0% after 1000 cycles at 0.13 mA cm-2,with an average cycling CE of 99.58%.

关键词： Electrolyte additive li dendrites li metal batteries liF and li3N-Rich electrode-electrolyte interphase liFePO4 cathode