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Effect of chemical and organic fertilization on soil carbon and nitrogen accumulation in a newly cultivated farmland

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Journal of Integrative Agriculture 2016年第3期15卷 658-666页

作者： yang rong SU yong-zhong WANG Tao yang Qin Linze Inland River Basin Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou Branch Chinese Academy of Sciences Institute of Vegetables Gansu Academy of Agricultural Sciences

Increased food demand from the rapidly growing human population has caused intensive land transition from desert to farmland in arid regions of northwest China. In this developing ecosystem, the optimized fertilization strategies are becoming an urgent need for sustainable crop productivity, efficient resources use, together with the delivery of ecosystems services including soil carbon（C） and nitrogen（N） accumulation. Through a 7-year field experiment with 9 fertilization treatments in a newly cultivated farmland, we tested whether different fertilizations had significant influences on soil C and N accumulation in this developing ecosystem, and also investigated possible mechanisms for this influence. The results showed that applying organic manure in cultivated farmland significantly increased the soil C and N accumulation rates; this influence was greater when it was combined with chemical fertilizer, accumulating 2.01 t C and 0.11 t N ha^（–1） yr^（–1） in the most successful fertilization treatment. These high rates of C and N accumulation were found associated with increased input of C and N, although the relationship between the N accumulation rate and N input was not significant. The improved soil physical properties was observed under only organic manure and integrated fertilization treatments, and the significant relationship between soil C or N and soil physical properties were also found in this study. The results suggest that in newly cultivated farmland, long term organic manure and integrated fertilization can yield significant benefits for soil C and N accumulation, and deliver additional influence on physical properties.

关键词： C and N accumulation sandy farmland chemical fertilizer manure soil physical property

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Multiobjective extremal optimization with applications to engineering design

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1905-1911页

作者： CHEN Min-rong LU yong-zai yang Gen-ke Department of Automation Shanghai Jiao Tong University Shanghai 200240. China College of information Science and Technology Jinan Universitly Guangzhou 510632 China College of Automation Science and Engineering. South China University of Technology Guangzhou 510641 China

In this paper, we extend a novel unconstrained multiobjective optimization algorithm, so-called multiobjective extremal optimization （MOEO）, to solve the constrained multiobjective optimization problems （MOPs）. The proposed approach is validated by three constrained benchmark problems and successfully applied to handling three multiobjective engineering design problems reported in literature. Simulation results indicate that the proposed approach is highly competitive with three state-of-the-art multiobjective evolutionary algorithms, i.e., NSGA-11, SPEA2 and PAES. Thus MOEO can be considered a good alternative to solve constrained multiobjective optimization problems.

关键词： Multiobjective optimization Extremal optimization (EO) Engineering design

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The induced electric field distribution in the solar atmosphere

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Research in Astronomy and Astrophysics 2013年第6期13卷 729-738页

作者： rong Chen Zhi-Liang yang Yuan-yong Deng Department of Astronomy Beijing Normal University Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences

A method of calculating the induced electric field is presented. The induced electric field in the solar atmosphere is derived by the time variation of the magnetic field when the accumulation of charged particles is neglected. In order to derive the spatial distribution of the magnetic field, several extrapolation methods are introduced. With observational data from the Helioseismic and Magnetic Imager aboard NASA＇s Solar Dynamics Observatory taken on 2010 May 20, we extrapolate the magnetic field from the photosphere to the upper atmosphere. By calculating the time variation of the magnetic field, we can get the induced electric field. The derived induced electric field can reach a value of 102 V cm-1 and the average electric field has a maximum point at the layer 360 km above the photosphere. The Monte Carlo method is used to compute the triple integration of the induced electric field.

关键词： Sun: magnetic fields - Sun: atmosphere - Sun: activity

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Osmotic Adjustment of Soil Biocrust Mosses in Response to Desiccation Stress

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Pedosphere 2015年第3期25卷 459-467页

作者： ZHAO Xin SHI yong LIU yang JIA rong-Liang LI Xin-rong Key Laboratory of Stress Physiology and Ecology Shapotou Desert Research and Experiment Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

Biological soil crusts(biocrusts) widely occur in semiarid and arid regions throughout the world and play important roles in many desert ecosystems: protecting soil from wind erosion and detaining nutrient-rich dust and organic carbon. An experiment was conducted in the Shapotou revegetated area of the Tengger Desert, Ningxia Hui Autonomous Region of China to investigate the physiological responses of the dominant biocrust mosses, Bryum argenteum and Didymodon vinealis, to desiccant stress using different osmotic adjustments. B. argenteum and D. vinealis accumulated K+, total soluble sugar, sucrose, trehalose, proline, and glycine betaine during desiccation. The proline content of B. argenteum was about two times higher than that of D. vinealis. The K+and glycine betaine contents in B. argenteum were slightly higher than those in D. vinealis. In contrast, the total soluble sugar, sucrose,and trehalose contents in D. vinealis were about 3 to 5 times higher than those in B. argenteum. With gradual desiccation stress,the Na+content of B. argenteum was low and did not significantly change. On the contrary, the Na+content of D. vinealis sharply increased and reached a very high level of about 10 to 18 times higher than that of B. argenteum, indicating that B. argenteum and D. vinealis gradually adapted to desiccation stress by osmotic substances accumulation to different degrees.

关键词： biological soil crusts Bryum argenteum compatible solute Didymodon vinealis drought stress

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Hlder Continuity for a Class of Strongly Degenerate Schrdinger Operator Formed by Vector Fields

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Acta Mathematicae Applicatae Sinica 2013年第2期29卷 281-288页

作者： yong-yang JIN Jie-lin L rong-fei LIN Department of Applied Mathematics Zhejiang University of Technology Zhejiang Vocational College of Commerce Department of Mathematics Taizhou University

In this paper we obtain the H61der continuity property of the solutions for a class of degenerate Schr6dinger equation generated by the vector fields：∑i,j=1^m Xj^＊（aij（x）Xiu）＋bXu=uu=0,where X = {X1,.-. ,Xm} is a family of C^∞ vector fields satisfying the H6rmander condition, and the lower order terms belong to an appropriate Morrey type space.

关键词： Hoe1der continuity degenerate SchrSdinger operator green function

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Influence of matrix physical properties on flow characteristics in dual network model

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Petroleum Science 2023年第4期20卷 2244-2252页

作者： Chen-Chen Wang yong-Fei yang Deng-Lin Han Miao-Miao Su rong-rong Hu Cooperative Innovation Center of Unconventional Oil and Gas Yangtze UniversityWuhan430100HubeiChina Laboratory of Reservoir Microstructure Evolution and Digital Characterization Yangtze UniversityWuhan430100HubeiChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina School of Geosciences Yangtze UniversityWuhan430100HubeiChina College of Resources and Environment Yangtze UniversityWuhan430100HubeiChina School of Petroleum Engineering Yangtze UniversityWuhan430100HubeiChina

The tight oil formation develops with microfractures and matrix pores,it is important to study the influence of matrix physical properties on flow *** first,the representative fracture and matrix samples are selected respectively in the dual media,the fracture and matrix digital rocks are constructed with micro-CT scanning at different resolutions,and the corresponding fracture and matrix pore networks are extracted,***,the modified integration method is proposed to build the dual network model containing both fracture and matrix pore-throat elements,while the geometric-topological structure equivalent matrix pores are generated to fill in the skeleton domain of fracture network,the constructed dual network could describe the geometric-topological structure characteristics of fracture and matrix pore-throat *** last,by adjusting the matrix pore density and the matrix filling domain factor,a series of dual network models are obtained to analyze the influence of matrix physical properties on flow characteristics in *** can be seen that the matrix system contributes more to the porosity of the dual media and less to the *** the decrease in matrix pore density,the porosity/permeability contributions of matrix system to dual media keep decreasing,but the decrease is not significant,the oil-water co-flow zone decreases and the irreducible water saturation increases,and the saturation interval dominated by the fluid flow in the fracture keeps *** the decrease in matrix filling domain factor,the porosity/permeability contributions of matrix system to dual media decreases,the oil-water co-flow zone increases and the irreducible water saturation decreases,and the saturation interval dominated by the fluid flow in the fracture keeps *** results can be used to explain the dual-media flow pattern under different matrix types and different fracture control volumes during tight oil production

关键词： Network integration Dual media Flow characteristics Matrix pore density Matrix filling domain

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Investigation of reinforcement of the modified carbon black from wasted tires by nuclear magnetic resonance

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第8期7卷 1440-1446页

作者： ZHOU Jie yang yong-rong REN Xiao-hong STAPF Siegfried UNILAB Research Center for Chemical Reaction Engineering School of Material Science and Chemical Engineering Zhejiang University Hangzhou 310027. China） Institute of Macromolecular Chemistry and Technical Chemistry RWTH-Aachen Worringerweg 1 D-52056 Germany

Pyrolysis has the potential of transforming waste into recyclable products. Pyrolytic carbon black (PCB) is one of the most important products from the pyrolysis of used tires. Techniques for surface modifications of PCB have been developed. One of the most significant applications for modified PCB is to reinforce the rubber matrix to obtain high added values. The transverse relaxation and the chain dynamics of vulcanized rubber networks with PCB and modified PCB were studied and compared with those of the commercial carbon blacks using selective 1H transverse relaxation (T2) experiments and dipolar correlation effect (DCE) experiments on the stimulated echo. Demineralization and coupling agent modification not only intensified the interactions between the modified PCB and the neighboring polyisoprene chains, but also increased the chemical cross-link density of the vulcanized rubber with modified PCB. The mechanical testing of the rubbers with different kinds of carbon blacks showed that the maximum strain of the rubber with modified PCB was improved greatly. The mechanical testing results confirmed the conclusion obtained by nuclear magnetic resonance (NMR). PCB modified by the demineralization and NDZ-105 titanate coupling agent could be used to replace the commercial semi-reinforcing carbon black.

关键词： Pyrolytic carbon black (PCB) Nuclear magnetic resonance (NMR) Relaxation Dipolar correlation effect (DCE) Reinforcement

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Formation,Stability,Geometry and Band Structure of Organically Surface-Modified Germanane

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Journal of Materials Science & Technology 2017年第1期33卷 59-64页

作者： Hui Jia rong Wang Zhenyi Ni yong Liu Xiaodong Pi Deren yang State Key Laboratory of Silicon Materials and Department of Materials Science and Engineering Zhejiang University Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of Technology

Surface modification may be an effective means for controlling the properties of germanane, i.e., hydrogenated germanene. In this work, we investigate the formation, stability, structure and electronic properties of surface-modified germanane that results from the hydrogermylation, alkoxylation, aminization or phenylation of germanane. By assuming the typical organic surface coverage of -33%, we have com- pared organically surface-modified germanane with germanene and germanane in the framework of density functional theory. It is found that organically surface-modified germanane may all stably exist despite the endothermic nature of organic surface modification. Organic surface modification leads to the de- crease of the Ge--Ge bond length and the Ge--Ge-Ge bond angle ofgermanane, while causing the buckling distance of germanane to increase. Hydrogenation makes germanene change from a semimetal to a direct- bandgap semiconductor. Organic surface modification further impacts the band structure of the resulting germanane. Hydrogermylated/alkoxylated germanane is a direct-bandgap semiconductor, while aminated/ phenylated germanane is an indirect-bandgap semiconductor. All the organic surface modification gives rise to the increase of the bandgap of germanane.

关键词： Germanane Surface modification Density functional theory Band structure

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Quasi-steady aerodynamic characteristics of Terminal Sensitive Bullets with short cylindrical portion

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Defence Technology（防务技术） 2021年第2期17卷 633-649页

作者： yong-liang yang Rui Guo rong-zhong Liu Liang Chen Bo-yang Xing Bo-bo Zhao School of Mechanical Engineering Nanjing University of Science and TechnologyXiaolingwei 200210094NanjingChina The Seventh Design Department Aerospace Science and Technology CorporationThe Seventh Research Institute610100ChengduChina Unit 31102 of PLA 210000NanjingChina

The aerodynamic characteristics are vital for short cylindrical Terminal Sensitive Bullets(TSB)with lowaspect ratio,especially in terminal ***,there is little research in terms of the TSB andshort cylinder with two free ends,and particularly in this trajectory,where the scanning angleβand rollangle a vary over a broad range between 0°and *** this work wind tunnel experiments are firstconducted to learn the effects of Reynolds number and scanning angle on aerodynamic parameters forshort cylinder with aspect ratio L/D=*** to infinite cylinder,for the short cylinder with two freeends,the drag crisis phenomenon still exists in the critical regime 1.7×10^(5)≤Re≤6.8×10^(5).Then 3Dsimulations are performed to demonstrate the aerodynamic characteristics of short cylinder and TSBover a broad range of Re,L/D,a and *** sensitivity analysis of time step and grid are presented as ***β3=0,for short cylinder,the drag crisis phenomenon was also observed in the simulation,but notas obvious as in the wind tunnel *** some attitudes,there is an obvious Karman vortexin the wake ofshort cylinder and *** correlation between time-averaged aerodynamic coefficients and L/D,Re,a&l is *** vortex shedding frequency and shear layer behavior are obtained for quasi-steadyand unsteady ***,the effect of end's shape on drag reduction and vortex shedding frequency isanalyzed.

关键词： Turbulent flows around bluff body Critical regime Flow-induced structural vibration

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A Study of Intermediate Energy Proton-^16O Elastic Scattering Based on the α-Particle Model

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Communications in Theoretical Physics 2007年第4期47卷 711-714页

作者： ZHANG rong yang yong-Xu LU Xiao LI Qing-Run Department of Physics Guangxi Normal University Guilin 541004 China College of Science China University of Mining and Technology Xuzhou 221008 China Institute of High Energy Physics Academia Sinica Beijing 100039 China

In the framework of KMT multiple scattering theory, an optical potential for the intermediate energy proton-160 elastic scattering is presented based on the α particle model of 160. The differential cross sections, the analyzing powers, and the total cross sections of the intermediate energy proton-160 scattering have been calculated by using the obtained optical potential. The main features of the measured angular distributions of the cross section and the analyzing power can be well described. The calculated total cross sections are in good agreement with the experimental data at energies below 0.7 GeV and underestimate the data about 8% at higher energies.

关键词： proton-nucleus elastic scattering nuclear a-particle model optical potential

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