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Effect of Long-Term Fertilization on Soil Productivity on the North China Plain

Pedosphere 2015年第3期25卷 450-458页

作者： WANG Jing-yan yan xiao-yuan GONG Wei Sichuan Provincial Key Laboratory of Ecological Forestry Engineering Sichuan Agricultural University State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of Sciences

Soil productivity is the ability of a soil, in its normal environment, to support plant growth and can be evaluated with respect to crop production in unfertilized soil within the agricultural ecosystem. Both soil productivity and fertilizer applications affect crop yields. A long-term experiment with a winter wheat-summer maize rotation was established in 1989 in a field of the Fengqiu State Key Agro-Ecological Experimental Station, a region typical of the North China Plain, including seven treatments： 1） a balanced application of NPK chemical fertilizers （NPK）; 2） application of organic fertilizer （OM）; 3） application of 50% organic fertilizer and 50% NPK chemical fertilizers （1/2OMN）; 4） application of NP chemical fertilizers （NP）; 5） application of PK chemical fertilizer （PK）; 6） application of NK chemical fertilizers （NK）; and 7） unfertilized control （CK）. To investigate the effects of fertilization practices on soil productivity, further pot tests were conducted in 2007-2008 using soil samples from the different fertilization treatments of the long-term field experiment. The soil sample of each treatment of the long-term experiment was divided into three pots to grow wheat： with no fertilization （Potunf）, with balanced NPK fertilization （POtNPK）, and with the same fertilizer（s） of the long-term field experiment （Potori）. The fertilized soils of the field experiment used in all the pot tests showed a higher wheat grain yield and higher nutrient uptake levels than the unfertilized soil. Soil productivity of the treatments of the field experiment after 18 years of continuous fertilizer applications were ranked in the order of OM 〉 1/2OMN 〉 NPK 〉 NP 〉 PK 〉 NK 〉 CK. The contribution of soil productivity of the different treatments of the field experiment to the wheat grain yield of Potori was 36.0%-76.7%, with the PK and NK treatments being higher than the OM, 1/2OMN, NPK, and NP treatments since the soil in this area was deficient in N and P and rich in K. Wheat g

关键词： balanced fertilization chemical fertilizer crop yield soil fertility nutrient use efficiency organic fertilizer soil organic matter

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Multiple Lagrange stability and Lyapunov asymptotical stability of delayed fractional-order Cohen-Grossberg neural networks

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Chinese Physics B 2020年第2期29卷 196-205页

作者： Yu-Jiao Huang xiao-yan yuan Xu-Hua yang Hai-Xia Long Jie xiao Zhijiang College Zhejiang University of TechnologyHangzhou 310024China College of Computer Science and Technology Zhejiang University of TechnologyHangzhou 310023China

This paper addresses the coexistence and local stability of multiple equilibrium points for fractional-order Cohen-Grossberg neural networks(FOCGNNs)with time *** on Brouwer's fixed point theorem,sufficient conditions are established to ensure the existence of Πi=1^n(2Ki+1)equilibrium points for *** the use of Hardy inequality,fractional Halanay inequality,and Lyapunov theory,some criteria are established to ensure the local Lagrange stability and the local Lyapunov asymptotical stability of Πi=1^n(Ki+1)equilibrium points for *** obtained results encompass those of integer-order Hopfield neural networks with or without delay as special *** activation functions are nonlinear and *** could be many corner points in this general class of activation *** structure of activation functions makes FOCGNNs could have a lot of stable equilibrium *** of multiple stable equilibrium points is necessary when neural networks come to pattern recognition and associative ***,two numerical examples are provided to illustrate the effectiveness of the obtained results.

关键词： fractional-order Cohen-Grossberg neural networks multiple Lagrange stability multiple Lyapunov asymptotical stability time delays

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PM_(2.5) obtained from urban areas in Beijing induces apoptosis by activating nuclear factor-kappa B

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Military Medical Research 2017年第4期4卷 200-209页

作者： Hui Peng xiao-Hong Zhao Ting-Ting Bi xiao-yan yuan Jia-Bin Guo Shuang-Qing Peng Evaluation and Research Center for Toxicology Institute of Disease Control and Prevention Academy of Military Medical Sciences Beijing Key Laboratory of Bioactive Substances and Functional Foods Beijing Union University

Background: Particulate matter(PM), which has adverse effects on citizen health, is a major air pollutant in Beijing city. PM_(2.5) is an indicator of PM in urban areas and can cause serious damage to human health. Many epidemiological studies have shown that nuclear factor-kappa B(NF-κB) is involved in PM_(2.5)-induced cell injury, but the exact mechanisms are not well ***: The cytotoxic effects of PM_(2.5) at 25–1600μg/ml for 24 h were determined by MTT assay in Chinese hamster ovary cells(CHO) cells. Flow cytometry was used to determine the apoptosis rate induced by PM_(2.5). The destabilized enhanced green fluorescent protein(d2 EGFP) green fluorescent protein reporter system was used to determine the NF-κB activity induced by PM_(2.5). The expression of pro-apoptotic Bcl-2-associated death promoter(BAD) proteins induced by PM_(2.5) was determined by Western blotting to explore the relationship between PM_(2.5) and the NF-κB signaling pathway and to determine the toxicological mechanisms of PM_(2.5).Results: PM_(2.5) collected in Beijing urban districts induces cytotoxic effects in CHO cells according to MTT assay with 72.28% cell viability rates even at 200μg/ml PM_(2.5) and flow cytometry assays with 26.97% apoptosis rates at 200μg/ml PM_(2.5). PM_(2.5) increases the activation levels of NF-κB, which have maintained for 24 h. 200μg/ml PM_(2.5) cause activation of NF-κB after exposure for 4 h, the activation peak appears after 13.5 h with a peak value of 25.41%. The average percentage of NF-κB activation in whole 24 h is up to 12.90% by 200μg/ml PM_(2.5). In addition, PM_(2.5) decreases the expression level of the pro-apoptotic protein BAD in a concentration-dependent ***: PM_(2.5) induces NF-κB activation, which persists for 24 h. The expression of pro-apoptotic protein BAD decreased with increased concentrations of PM_(2.5). These findings suggest that PM_(2.5) plays a major role in apoptosis by activating the NF-κB signaling path

关键词： Particulate matter NF-κB pathway Apoptosis BAD protein

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Changes in paddy cropping system enhanced economic profit and ecological sustainability in central China

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Journal of Integrative Agriculture 2022年第2期21卷 566-577页

作者： ZHOU Yong yan xiao-yuan GONG Song-ling LI Cheng-wei ZHU Rong ZHU Bo LIU Zhangyong WANG xiao-long CAO Peng Hubei Collaborative Innovation Centre for Grain Industry/College of Agriculture Yangtze UniversityJingzhou 434025P.R.China Engineering Research Center of Ecology and Agricultural Use of Wetland of Ministry of Education Yangtze UniversityJingzhou 434025P.R.China College of Agriculture South China Agricultural UniversityGuangzhou 510642P.R.China Agricultural Technology Extension Station of Hubei Province Wuhan 430070P.R.China

In China,the traditional early and late season double rice(DR)system is declining accompanied by the fast increase of two newly developed cropping systems:ratoon rice(RR)and rice-crawfish(RC).Three methodologies:economic analysis,emergy evaluation and life cycle assessment(LCA)were employed to evaluate the economics and sustainability of this paddy cropping system *** analysis indicated that the income and profit of the RC system were far larger than those of RR and *** income to costs ratio of RR and RC increased by 25.5 and 122.7%compared with that of DR,*** had the highest emergy input thanks to increasing irrigation water,electricity,juvenile crawfish and forage input while RR showed a lower total emergy and nonrenewable emergy input,such as irrigation water,electricity,fertilizers and pesticides than *** environmental loading ratios decreased by 16.7-50.4%when cropping system changed from DR to RR or from DR to RC while the emergy sustainability indexes increased by 22.6-112.9%.The life cycle assessment indicated lower potential environmental impacts of RR and RC,whose total environmental impact indexes were 35.0-61.0%lower than that of *** yield of RR was comparable with that of DR in spite of less financial and emergy input of RR,but RC had a much lower grain yield(a 53.6%reduction compared to DR).These results suggested that RR is a suitable cropping system to achieve the food security,economic and environmental goals.

关键词： paddy cropping system changes economic analysis emergy evaluation LCA food security central China

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Progress in Significant Soil Science Fields of China over the Last Three Decades: A Review

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Pedosphere 2011年第1期21卷 1-10页

作者： ZHAO Qi-Guo HE Ji-Zheng yan xiao-yuan ZHANG Bin ZHANG Gan-Lin CAI Zu-Cong State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) State Key Laboratory of Urban and Regional Ecology Research Centre for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 (China) Key Laboratory of Plant Nutrition and Nutrient Cycling of the Ministry of Agriculture of China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 (China)

Due to continuous decreases in arable land area and continuous population increases,Chinese soil scientists face great challenges in meeting food demands,mitigating adverse environmental impacts,and sustaining or enhancing soil productivity under intensive *** the aim of promoting the application of soil science knowledge,this paper reviews the achievements of Chinese scientists in soil resource use and management,soil fertility,global change mitigation and soil biology over the last 30 *** this period,soil resource science has provided essential support for the use and exploitation of Chinese soil resources,and has itself developed through introduction of new theories such as Soil Taxonomy and new technologies such as remote *** fertility science has contributed to the alleviation and elimination of impeding physical and chemical factors that constrain availability of essential nutrients and water in soils,the understanding of nutrient cycling in agroecosystems,and the increase in nutrient use efficiency for sustainable crop *** soil scientists have contributed to the understanding of the cropland's role in global change,particularly to the understanding of methane and nitrous oxide emission from rice fields and the effect of elevated carbon dioxide and ozone on rice-wheat *** biology research has progressed in biological N fixation,distribution of fauna in Chinese soils,and bioremediation of polluted soils.A new generation of soil scientists has arisen in the last three *** gaps between research and application in these soil science fields are also discussed.

关键词： global change soil biology soil fertility soil resources

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NOX -Catalyzed Gas-Phase Activation of Methane: the Formation of Hydrogen

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Journal of Natural Gas Chemistry 2003年第2期12卷 90-92页

作者： Chaoxian xiao, Zhen yan, yuan KouCollege of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China College of Chemistry/Molecular Eng. Peking University Beijing 100871 China

NO_x-catalyzed oxidation of methane without a solid catalyst wasinvestigated, and a hydrogen selectivity of 27% was obtained with an overall methane conversion of34% and a free O_2 concentration of 1.7% at 700℃.

关键词： gas-phase oxidation methane activation methane nitrogen oxide hydrogen

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Review of copper and copper alloys as immune and antibacterial element

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Transactions of Nonferrous Metals Society of China 2022年第10期32卷 3163-3181页

作者： yang-gang WANG Hao-yang LI xiao-yan yuan yan-bin JIANG Zi-an xiao Zhou LI School of Materials Science and Engineering Central South UniversityChangsha 410083China Teaching and Research Section of Clinical Nursing Xiangya HospitalCentral South UniversityChangsha 410008China Department of Otolaryngology Second Xiangya HospitalCentral South UniversityChangsha 410011China

This review discussed the relationship among copper,human,and *** plays an important role in human *** can boost human immune defense reactions at recommended intake *** content mainly focused on copper antibacterial activity and copper antibacterial *** stated that copper antibacterial activity is affected by copper homeostasis mechanisms in bacteria,adhesion,humidity,strain specificity,and manufacturing methods of antibacterial *** the preparation of particle antibacterial agents and surface antibacterial agents,this review discussed several manufacturing methods,such as sol−gel,cold spray,and biosynthesis belonging to chemical synthesis,physical synthesis,and biological synthesis,***−gel method contributes to the preparation of particle agents and surface *** spray technique is utilized in synthesis of surface copper *** is a novel technology which can be applied in nanoparticle agent preparation.

关键词： immunity toxicity antibacterial activity copper homeostasis adhesion humidity strain specificity antibacterial agents mechanisms

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Primary Studies on Burnup Estimation of Irradiated Uranium by Dtermining 236U/238U in Contaminated Environmental Samples JIANG xiao-yan,ZHANG Ji-long,ZOU Wei,Chang Zhi-yuan

Primary Studies on Burnup Estimation of Irradiated Uranium b...

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作者： JIANG xiao-yan ZHANG Ji-long ZOU Wei Chang Zhi-yuan

U/U of the environmental sample can indicate the existence of uranium irradiation,and even can be uesd to estimate the burnup of nuclear spent fuel.A study on the burnup estimation of irradiated uranium which was mixed with natural uranium was carried out by measuring the U/U and U/U in the samples by using MC-ICP-MS. According to the equation(1) and(2),a programme for calculating the burnup of the irradiated

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Study to mechanism of fluorescence enhancement of Dy3＋-Gd3＋- SSA-CTMAB system by resonance scattering-light spectroscopy

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Journal of Chemistry and Chemical Engineering 2009年第12期3卷 1-6,14页

作者： SA Pan-pan LIU xiao-yan YAO yuan-yuan ZHENG Zhi-gang ZHANG xiao-wei YIN Hong-zong College of Chemistty and Material Science Shandong Agricultural University Taian 271018 China

The fluorescence enhancement mechanism of Dy3＋-Gd3＋- SSA-CTMAB system was studied by the resonance light scattering and fluorescence spectrum. In this paper, the influencing factors including the concentration of Gd3＋, ligands, pH value as well as surfactants were studied. As a result, the optimal experimental conditions were obtained. The existence of molecule congeries was proved by scattering-light spectrum.

关键词： dysprosium gadolinium sulfonic salicylic acid (SSA) hexadecyl trimethyl ammonium bromide (CTMAB) fluorescent spectroscopy resonance scattering- light spectroscopy fluorescence enhancement

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RPC预制管混凝土组合柱组合效应试验研究

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湖南大学学报（自然科学版） 2017年第3期44卷 88-96页

作者：单波刘志肖岩胡源湖南大学建筑安全与节能教育部重点实验室湖南长沙410082 南京工业大学土木工程学院江苏南京211816 湖南大学工程结构损伤诊断湖南省重点实验室湖南长沙410082

配有高强螺旋箍筋的活性粉末混凝土(RPC)预制管内浇筑混凝土,形成一种新型组合结构——RPC预制管混凝土组合柱(CFRT).对9个不同箍筋间距的CFRT,3个箍筋约束混凝土柱和3个RPC空管开展轴向抗压试验,研究RPC管与内部混凝土之间的组合效应,... 详细信息

配有高强螺旋箍筋的活性粉末混凝土(RPC)预制管内浇筑混凝土,形成一种新型组合结构——RPC预制管混凝土组合柱(CFRT).对9个不同箍筋间距的CFRT,3个箍筋约束混凝土柱和3个RPC空管开展轴向抗压试验,研究RPC管与内部混凝土之间的组合效应,以及箍筋间距对CFRT轴压性能的影响.结果表明:在荷载峰值下,组合柱中的RPC管没有出现明显的剥落现象,构件截面较为完整;CFRT柱的承载力显著高于对应的箍筋约束混凝土柱和RPC空管两者单独的承载力之和,在承载力上实现了超叠加;CFRT中配置的箍筋间距越小,组合柱的抗压性能越好;基于Mander模型和相应的简化,对CFRT的组合效应进行了分析,RPC管对组合柱的轴向承载力贡献在0.22~0.26之间,且随箍筋间距的增大而有提高的趋势,并提出了CFRT轴向承载力计算方法.

关键词：活性粉末混凝土(RPC) 约束高强箍筋轴向受压组合效应

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