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Phosphorus limitation on photosynthesis of two dominant understory species in a lowland tropical forest

Journal of Plant Ecology 2014年第6期7卷 526-534页

作者： feifei zhu Xiankai Lu Jiangming Mo Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of SciencesXingke RoadTianheGuangzhou 510650China Graduate University of the Chinese Academy of Sciences Yuquan RoadShijingshanBeijing 100049China

Aims Elevated nitrogen(N)deposition in tropical regions may accelerate ecosystem phosphorus(P)***,it is not explicitly addressed that how changes in soil N and P availability affect foliar nutrients and photosynthesis of plants in tropical *** this study,we examined the effects of N and P additions on foliar nutrients and net photosynthesis of two dominant understory species,Randia can-thioides(***)and Cryptocarya concinna(***)in an N-saturated old-growth tropical forest(>400-year-old)in south-ern *** A full factorial NP addition experiment(2×2)was established in 2007 and continued through August *** treatments,including control,N addition(150 kg N ha^(−1) year^(−1)),P addi-tion(150 kg P ha^(−1) year^(−1))and NP addition(150 kg N ha^(−1) year^(−1) plus 150 kg P ha^(−1) year^(−1))were set up in this *** traits maximum photosynthetic CO_(2) assimilation(Amax),stomatal conductance(gs),leaf transpiration(E),light satu-rating point,concentrations of chlorophyll a/b and foliar nutri-ents(N and P)of the two species were measured with standard *** Findings Three years of N addition had no significant effects on any measured photosynthetic parameter of either ***,N addition significantly elevated foliar N and P concentrations of one species(***),resulting in lower photosynthetic nitrogen use effi-ciency(PNUE).N treatments decreased foliar P concentration of the other(***),resulting in increased photosynthetic phos-phorus use efficiency,which was potentially related to N-induced P *** contrast,positive effects of P treatments on gs of ***-thioides,Amax and chlorophyll a+b of *** were observed.P treatments also elevated foliar P and PNUE of both species,imply-ing P induced more efficient use of *** results suggested a more important role of P than N on influencing photosynthetic traits of these two understory *** of P shorta

关键词： N saturation P limitation photosynthesis lowland tropical forests southern China

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Composites Based on GM(1,1)-Markov in the Salt Spray Corrosion Environment

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Journal of Renewable Materials 2022年第11期10卷 2973-2987页

作者： Jianqiao Yu Hongxia Qiao Theogene Hakuzweyezu feifei zhu School of Civil Engineering Lanzhou University of TechnologyLanzhou730050China Western Ministry of Civil Engineering Disaster Prevention and Mitigation Engineering Research Center Lanzhou University of TechnologyLanzhou730050China

This study was designed to solve the problem of magnesium hazards due to potash extraction in the salt lake *** basalt fiber(BF)as the reinforcement material and magnesium oxychloride cement(MOC)as the gelling material,a BF/MOC composite material was ***,the effect of BF addition content on the basic mechanical properties of the composites was ***,through the salt spray corrosion test,the durability damage deterioration evaluation analysis was carried out from both macroscopic and microscopic aspects using mass change,relative dynamic modulus of elasticity(RDME)change,SEM analysis and FT-IR ***,a GM(1,1)-Markov model was established to predict the durability life of composite materials by using durability evaluation *** results show that:when the BF content is 0.10%(by volumetric content),the composites have the best mechanical properties and resistance to salt spray ***,when the volume of BF content exceeds 0.10%,a large number of magnesium salt crystallization products are observed from the microscopic point of view,and the corrosion of the main strength phase of MOC is more *** prediction results of the GM(1,1)-Markov model are highly identical with the raw *** addition,using the change of RDME as a predictor,RDME is more sensitive to environmental factor compared to the change of *** using the change of RDME as a threshold indicate that MOC-BF0.10 has the longest durability life,which is 836 *** model is important to promote the application of MOC composites in the salt lake region and to promote the healthy development of green building materials.

关键词： Basalt fiber magnesium oxychloride cement salt spray corrosion test durability damage deterioration GM(1,1)-Markov model

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Trajectories in nitrogen availability during forest secondary succession:illustrated by foliarδ^(15)N

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Ecological Processes 2022年第1期11卷 400-410页

作者： Ying Tu Ang Wang feifei zhu Geshere Abdisa Gurmesa Erik A.Hobbie Weixing zhu Yunting Fang CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyangChina Qingyuan Forest CERN ShenyangChina Key Laboratory of Stable Isotope Techniques and Applications ShenyangLiaoning ProvinceChina Earth Systems Research Center Morse HallUniversity of New HampshireDurhamNHUSA Department of Biological Sciences Binghamton UniversityThe State University of New YorkBinghamtonNYUSA University of Chinese Academy of Sciences BeijingChina

Background:Forest succession is an important ecological process and has been studied for more than a ***,changes in nitrogen(N)availability during succession remain unclear as they may lead to either N satura-tion or N ***,we propose a conceptual model to illustrate changes in N availability during four stages of secondary succession using the natural abundance of ^(15) N in plant leaves(foliarδ^(15)N).We predicted that N availability would decline in the early stages of succession and then increase in late stages,coinciding with the changes in foliarδ^(15)N,with the inflection point varying in different climate *** on foliarδ^(15)N from 16 succession sequences were synthesized to explore changes in N availability during forest ***:The compiled data were consistent with the proposed conceptual ***δ^(15)N in boreal and temperate forests decreased significantly in the first two stages of succession(estimated to last at least 66 years in temperate forests),at a rate of 0.18‰and 0.38‰per decade,respectively,and decreased slightly in tropical forests in the first 23 ***δ^(15)N is projected to increase in later stages in all forests,which is supported by observations in both temperate and tropical *** inflection points of N availability when N limitation peaked during succession were different in different climate zones,implying different ecosystem N ***:Our study reconciles the controversies regarding changes in N availability during forest secondary *** findings are also useful for predicting the recovery of N and carbon accumulation during ***,studies on forest secondary succession using foliarδ^(15)N have thus far been limited,and more research should be conducted to further verify the conceptual model proposed here.

关键词： Foliarδ^(15)N Forest secondary succession Nitrogen availability Space-for-time substitution

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Nitrogen uptake strategies of mature conifers in Northeastern China, illustrated by the ^(15)N natural abundance method

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Ecological Processes 2021年第1期10卷 470-480页

作者： Xulun Zhou Ang Wang Erik A.Hobbie feifei zhu Xueyan Wang Yinghua Li Yunting Fang School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110164China Key Laboratory of Stable Isotope Techniques and Applications Shenyang 110016Liaoning ProvinceChina .4 Qingyuan Forest CERN Shenyang 110016China Earth Systems Research Center Morse HallUniversity of New HampshireDurhamNHUSA School of Energy and Water Resources Shenyang Institute of TechnologyFushun 113122China.

Background:Conifers partition different N forms from soil,including ammonium,nitrate,and dissolved organic N(DON),to sustain plant *** studies focused on inorganic N sources and specific amino acid forms using ^(15)N labelling,but knowledge of the contribution of DON to mature conifers’N uptake is still ***,we quantified the contribution of different N forms(DON ***_(4)^(+)***_(3)^(−))to total N uptake,based on ^(15)N natural abundance of plant and soil available N,in four mature conifers(Pinus koraiensis,Pinus sylvestris,Picea koraiensis,and Larix olgensis).Results:DON contributed 31%,29%,28%,and 24%to total N uptake by Larix olgensis,Picea koraiensis,Pinus koraiensis,and Pinus sylvestris,respectively,whereas nitrate contributed 42 to 52%and ammonium contributed 19 to 29%of total N uptake for these four coniferous ***:Our results suggested that all four conifers could take up a relatively large proportion of nitrate,while DON was also an important N source for the four *** that DON was the dominant N form in study soil,such uptake pattern of conifers could be an adaptive strategy for plants to compete for the limited available N sources from soil so as to promote conifer growth and maintain species coexistence.

关键词： Nitrogen uptake preference Organic nitrogen Inorganic nitrogen Coniferous plantation ^(15)N natural abundance Isotopic mixing model

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Cyanide-bridged single molecule magnet based on a manganese(Ⅲ) complex with TTF-fused Schiff base ligand

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Science China Chemistry 2015年第4期58卷 650-657页

作者： Long Cui feifei zhu Chanel F.Leong Jing Ru Feng Gao Deanna M.D’Alessandro Jinglin Zuo State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Nanjing National Laboratory of Microstructures Nanjing University School of Chemistry The University of Sydney

Reaction of [Mn（TTF-salphen）][OAc] （TTF-salphen2=2,2＇-（（2-（4,5-bis（methylthio）-1,3-dithiol-2-ylidene）-1,3-benzodithiole- 5,6-diyl）bis（nitrilomethylidyne）bis（pbenolate）dianion） and the cyanometalate building blocks [n-Bu4N][（Tp）Fe（CN）3] （Tp =Tris（pyrazolyl）hydroborate） or [n-Bu4N][Ru（salen）（CN）2] （salen2 =N,N＇-ethylenebis（salicylideneimine）dianion） resulted in the formation of two redox-active complexes, the dinuclear heterometallic complex [（Tp）Fe（CN）3Mn（TTF-salphen）＇CH3OH] （1） and the one dimensional complex [Ru（salen）（CN）2Mn（TTF-salphen）]n （2）. Both complexes were characterized by X-ray crystallography and solid state electrochemistry, in addition to static and dynamic magnetic measurements. Antiferromagnetic couplings are found to be operative between metal ion centers bridged by cyanide in both complexes. Complex 1 exhibited field-induced SMM behavior with an energy barrier of 13.8 K. The introduction of the redox-active TTF unit into cyanidebridged complexes with interesting magnetic properties renders them promising candidates for the construction of new hybrid inorganic-organic materials.

关键词： cyanide complexes single molecule magnets tetrathiafulvalene multifunctional materials

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Study on Absorption and Regeneration Performance of Novel Hybrid Solutions for CO_2 Capture

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China Petroleum Processing & Petrochemical Technology 2016年第1期18卷 66-72页

作者： Gao Jie Yin Jun zhu feifei Chen Xin Tong Ming Kang Wanzhong Zhou Yanbo Lu Jun Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education East China University of Science & Technology SINOPEC Ningbo Engineering Co. Ltd.

Recently, a kind of hybrid solution MEA-methanol shows a better CO_2 capture performance over aqueous MEA solution. However, the vaporization of methanol is the biggest disadvantage that hinders its application, so it is necessary to minimize the vaporization of methanol during both the absorption and regeneration processes. In this work, two kinds of hybrid solutions were studied and compared with aqueous MEA solution and MEA-methanol solution, including MEA/TEA/methanol solution and MEA/glycerol/methanol solution. The absorption property of MEA/glycerol/methanol solution is better than aqueous MEA solution within a certain period of time and the absorption property of MEA/TEA/methanol solution is too poor to be used in CO_2 capture. By increasing the concentration of TEA and decreasing the concentration of MEA, the absorption rate, CO_2 capture efficiency and absorption capacity all decreased. Upon adding glycerol, the cyclic capacity decreased and the generation temperature increased, and moreover, the density and viscosity also increased considerably. So after adding TEA and glycerol, the CO_2 capture performance of MEAmethanol solvent cannot be improved.

关键词： CO2 capture MEA methanol glycerol hybrid solvent

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Study on CO_2 Absorption by Aqueous Benzylamine and Its Formulations with Monoethanolamine as a Component for Post-Combustion Capture Process

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China Petroleum Processing & Petrochemical Technology 2016年第3期18卷 7-14页

Benzylamine(BZA) has been identified as a promising candidate for CO_2 capture process; however the evaluation of BZA in the packed column was very few. Thus, in this work, the absorption and regeneration performance of unblended BZA solvent as well as a series of amine concentrations and ratios in the formulations were studied using a semibatch bubbling reactor. And due to the formation of ivory-white precipitates in solvents containing higher BZA ratios, a 4:1 molar ratio of MEA/BZA mixed solvent was used to study its performance in a pilot-scale test bed. The results showed that a higher BZA ratio in the MEA/BZA mixed solvent resulted in a faster absorption rate, a higher mass transfer and heat transfer rate and a better cyclic performance, but the mass transfer rate of BZA decreased more quickly than MEA with the increase of CO_2 loading of the solvents. In addition, at high CO_2 loading in the MEA/ BZA mixed solvent with a molar ratio of 4:1, the ivory-white precipitates were generated which could cause blockage of the packing in the absorber, the stripper and the liquid pipelines.

关键词： benzylamine (BZA) monoethanolamine (MEA) post combustion CO2 capture pilot plant mass transfer

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On the inheritance and development of the traditional 72 Jingdezhen hand porcelain schemata

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International Journal of Technology Management 2014年第1期 1-3页

作者： feifei zhu Li Zhang School of Ceramic and Art Jingdezhen Ceramic InstituteJingdezhenJiangxi333403 China Jiangxi Ceramic & Art institute JingdezhenJiangxi333001 China

Jingdezhen, known as the ＂porcelain capital,＂ it is said that the Millennium kiln fire is constant here, its porcelain, with ＂ white as jade, bright as a mirror, as thin as paper, such as chime sound ＂ style, renowned at home and abroad. Area of Jingdezhen handmade porcelain craft is mainly Jingdezhen urban and rural areas. ＂State the number of Chinese porcelain, Porcelain peak is this all.＂ Over more than a thousand year, Jingdezhen system culminates best collection of industry of ancient Ming Yao, forming a unique handmade porcelain craft production system, creating the most brilliant piece of Chinese ceramic history. Their high achievements, impact, the craft, the varieties, which any other kilns at any time are difficult to match.

关键词： Inheritance Jingdezhen hand porcelain schemata

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PERIODIC AND NONPERIODIC OSCILLATIONS OF NONLINEAR ATMOSPHERIC WAVES FORCED BY PERIODIC THERMAL FORCING——SYSTEM WITHOUT DISSIPATION

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Science in China,Ser.B 1986年第10期29卷 1084-1095页

作者：金飞飞朱抱真 Institute of Atmospheric Physics Academia Sinica Beijing

In this paper, a baroclinic stable system with periodic forcing is used to discuss the dynamics of wave amplitude near the resonant forcing *** the first part, the linear resonant condition and weakly nonlinear resonant problem are analysed and two distinct periodic solutions with larger and smaller amplitudes are solved respectively for system without dissipation. When external forcing varies between the existence domains for these two kinds of periodic solution, nonperiodic oscillation appears, i.e. the so-called 'chaos' phenomenon.

关键词： PERIODIC AND NONPERIODIC OSCILLATIONS OF NONLINEAR ATMOSPHERIC WAVES FORCED BY PERIODIC THERMAL FORCING SYSTEM WITHOUT DISSIPATION

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治理环境,金字塔结构与公司业绩

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系统工程理论与实践 2017年第8期37卷 1963-1972页

作者：甄红线朱菲菲迟国泰东北财经大学会计学院/中国内部控制研究中心大连116025 北京大学光华管理学院北京100871 大连理工大学管理与经济学部大连116024

本文采用2005-2014年A股上市公司数据,研究公司内部金字塔结构和外部治理环境对公司业绩的影响.结果显示:第一,无论是衡量金字塔结构横向特征的"金字塔链条数",还是衡量金字塔结构纵向特征的"两权偏离度",都与公司业绩显著正相关;第二,... 详细信息

本文采用2005-2014年A股上市公司数据,研究公司内部金字塔结构和外部治理环境对公司业绩的影响.结果显示:第一,无论是衡量金字塔结构横向特征的"金字塔链条数",还是衡量金字塔结构纵向特征的"两权偏离度",都与公司业绩显著正相关;第二,外部治理环境的改善,能够提高公司业绩,尤其能够显著提升国有企业的绩效水平;第三,公司内部的金字塔结构和外部治理环境对公司业绩的影响具有交互作用,具体表现为,随着治理环境的改善,金字塔链条数对公司业绩的正效应增强(即递增效应),两权偏离度和终极所有者持有的现金流权对公司业绩的正效应减弱(即替代效应).本文的研究结论支持政府释权理论,为政府控股下的企业集团混合所有制改革提供理论参考与经验借鉴.

关键词：金字塔结构公司业绩治理环境两权偏离度

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