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Straw strip mulching:A sustainable technology for saving water and improving efficiency in dryland winter wheat production

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journal of Integrative Agriculture 2022年第12期21卷 3556-3568页

作者： LI Rui chai Shou-xi chai Yu-wei LI Ya-wei CHANG Lei CHENG Hong-bo Gansu Provincial Key Laboratory of Aridland Crop Science Lanzhou 730070P.R.China College of Agronomy Gansu Agricultural UniversityLanzhou 730070P.R.China College of Bioscience and Technology Gansu Agricultural UniversityLanzhou 730070P.R.China

An improved straw mulching model may be a sustainable agricultural production technology due to its improvements in soil water and the fertilizer environment by the recycling of waste straw resources.A four-year field experiment was conducted in a randomized block design on the Loess Plateau of northwestern China in 2015–2019,which aimed to study the effects of straw strip mulching(SSM)and conventional flat planting without mulching(CK)on soil water storage,water consumption characteristics,water use efficiency,precipitation use efficiency,winter wheat growth,economic benefits,and nutrient *** results obtained for the four years showed that the SSM treatment improved soil water storage in the 0–180 cm soil layer over the whole growth period,which was especially obvious in the 0–60 cm soil layer at the jointing and blooming *** with CK,SSM increased the contribution rate of precipitation to total evapotranspiration and increased it quite significantly by 20.4 percentage points in the earlier growth *** significantly reduced soil water storage consumption in the 0–180 cm soil layer and ultimately reduced evapotranspiration by 11.2 mm during the whole *** the 0–180 cm soil layer,SSM decreased evapotranspiration by 33.1 mm from the sowing to the jointing stages,but increased it by 19.5 mm from the jointing to the blooming *** addition,SSM improved the water use efficiency of grain yield by 21.6%and improved the precipitation use efficiency of grain yield by 18.6%,and it ultimately increased grain yield by 16.5%through improving spike number by 9.5%and kernel number per spike by 8.9%.SSM improved the water use efficiency of biomass yield by 13.5%and the precipitation use efficiency of biomass yield by 9.9%,and it ultimately increased biomass yield by 8.7%and plant height by 6.5%.Furthermore,SSM increased net income by 413 CNY ha–1 and the total amount of straw returned to the field after harvest by 8876–9619 kg ha–*** returning

关键词： soil water storage evapotranspiration water use efficiency soil nutrient

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EVOLUTION OF AS-CAST MICROSTRUCTURES OF 356 ALUMINIUM ALLOY CAST BY LIQUIDUS CASTING

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Acta Metallurgica Sinica(English Letters) 2003年第1期16卷 60-64页

作者： j.Dong G.M.Lu j.z.Cui z.H.zhao The Key Lab of Electromagnetic Processing of Materials Ministry of Education Northeastern UniversityShenyang 110004 China

A new method (liquidus casting) was used for 356 Al alloy semi-solid slurry making. The structures of 356 Al alloy cast by a Fe mould and semi-continuous casting machine at different temperatures were investigated. How the globular grains form was also discussed. The results show that either being cast by single Fe mould or semi-continuous machine, the micro structures are not conventional dendrites but fine and net-globular grains. The average gram size is smaller than 30μm and suitable enough for thixoforming, meanwhile it can improve the mechanical properties of following products. Under the suitable casting velocity and cooling intensity, most of global grains prolong their global growth and collide with each other before dendritic growth because of the large amount of the nucleation sites.

关键词： liqwdus casting microstructure 356 Al alloy

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Non-monotonic temperature evolution of nonlocal structure–dynamics correlation in Cuzr glass-forming liquids

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Chinese Physics B 2021年第7期30卷 370-375页

作者： W j jiang M z Li Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China

The structure–dynamics correlations in a nonlocal manner were investigated in Cuzr metallic glass-forming liquids via classical molecular dynamics simulations.A spatial coarse-graining approach was employed to incorporate the nonlocal structural information of given structural order parameters in the structure–dynamics *** is found that the correlation between structure order parameters and dynamics increases with increasing coarse-graining length and has a characteristic length ***,the characteristic correlation length exhibits a non-monotonic temperature evolution as temperature approaches glass transition temperature,which is not sensitive to the considered structure order *** results unveil a striking change in the structure–dynamics correlation,which involves no fitting theoretical *** findings provide new insight into the structure–dynamics correlation in glass transition.

关键词： metallic glass-forming liquid structure–dynamics correlation molecular dynamics simulation

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Deciphering deformation mechanisms of hierarchical dual-phase CrCoNi coatings

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journal of Materials Science & Technology 2020年第4期39卷 7-13页

作者： S.j.Tsianikas Y.Chen z.Xie School of Mechanical Engineering The University of AdelaideAdelaideSA5005Australia Centre for Advanced Thin Film Materials and Device Faculty of Materials and EnergySouthwest UniversityChongqing400715China School of Engineering Edith Cowan UniversityWA6027Australia

Hierarchical Cr Co Ni medium entropy alloy(MEA)thin films with a dual-phase face-centred cubic(FCC)and hexagonal closed-packed(HCP)nanostructure were prepared on M2 steel substrates by closed field unbalanced magnetron *** tests show an ultra-high hardness of 9.5 GPa,attributable to large amounts of innate planar defects(i.e.,growth twins and stacking faults)impeding dislocation motion in the coatings.A deep analysis of undeformed and post-mortem samples reveals grain refinement as the dominant deformation mechanism in FCC dominated regions,while phase transformation and shear banding played major roles in regions occupied by HCP *** grain refinement was facilitated by twin/matrix lamellae,with dislocations piling up and arranging into interconnecting grain *** shear banding was accelerated by innate planar defects in the HCP phase due to a lack of slip *** particular interest is the observation of HCP→FCC phase transformation,which was catalysed by deformation-induced grain reorientation with innate stacking faults acting as embryos to grow the FCC *** results of this work suggest that multiple deformation pathways could be activated in Cr Co Ni coatings with assistance of growth defects,thereby imparting these technically important coatings appreciable ductility.

关键词： Medium entropy alloys Sputter deposition Grain refinement Shear banding Phase transformation

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Recent Progress on Data-Based Optimization for MineralProcessing Plants

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Engineering 2017年第2期3卷 183-187页

作者： jinliang Ding Cuie Yang Tianyou chai State Key Laboratory of Synthetical Automation for Process Industries Northeastern University Shenyang 110819 China

In the globalized market environment, increasingly significant economic and environmental factors withincomplex industrial plants impose importance on the optimization of global production indices; such opti-mization includes improvements in production efficiency, product quality, and yield, along with reductionsof energy and resource usage. This paper briefly overviews recent progress in data-driven hybrid intelli-gence optimization methods and technologies in improving the performance of global production indicesin mineral processing. First, we provide the problem description. Next, we summarize recent progress indata-based optimization for mineral processing plants. This optimization consists of four layers： optimiza-tion of the target values for monthly global production indices, optimization of the target values for dailyglobal production indices, optimization of the target values for operational indices, and automation systemsfor unit processes. We briefly overview recent progress in each of the different layers. Finally, we point outopportunities for future works in data-based optimization for mineral processing plants.

关键词： Data-based optimization Plant-wide global optimization Mineral processing Survey

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Magnetic Properties of Ni Nanoparticles and Ni(C) Nanocapsules

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journal of Materials Science & Technology 2002年第2期18卷 99-100页

作者： z.j.Li G.H.Wen 等 ShenyangNationalLaboratoryforMaterialsScienceandInternationalCentreforMaterialsPhysics InstituteofMetalResearchChineseAcademyofSciencesShenyang110016China DepartmentofPhysics H

Structure and magnetic properties of Ni nanoparticles and Ni(C) nanocapsules were studied. The carbon atoms hardly affect the lattice of Ni to form Ni-C solid solution or nickel carbides. The large thermal irreversibility in zero-field-cooled and zero-field magnetization curves indicates magnetic blocking with a wide energy barrier. Saturation magnetization, remanent magnetization and coercivity of Ni(C) nanocapsules decrease with increasing temperature.

关键词： Nanoparticles Nanocapsules Magnetic properties

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A practical model for efficient anti-fatigue design and selection of metallic materials:Ⅰ.Model building and fatigue strength prediction

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journal of Materials Science & Technology 2021年第11期70卷 233-249页

作者： R.Liu P.zhang z.j.zhang B.Wang z.F.zhang Laboratory of Fatigue and Fracture for Materials Shi-changxu Innovation Center for Advanced MaterialsInstitute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China

The high cost and low efficiency of fatigue tests are bottleneck problem for the anti-fatigue design of metallic *** this problem,a theoretical fatigue model is proposed in this study,the possible applications have also been *** results would be introduced in two serial papers,in which the first paper focuses on the model building and the applications on fatigue strength prediction;the second paper put emphasis on the influencing factors of the model parameters and the applications on fatigue strength *** this first paper,a theoretical model is proposed considering both the strength and plastic restrictions of fatigue *** the model builds up a brief relationship among yield strength(Y),tensile strength(T)and fatigue strength(F),it is named as the Y-T-F *** the verification with fatigue strength data covering various kinds of metallic materials and loading conditions,this Y-T-F model exhibits both generality and *** the Y-T-F model,the efficient fatigue strength prediction could be conducted by brief linear fitting and calculation,just through yield strength,tensile strength and several known fatigue strength ***,through its deduced Y-F model,the analytical formula of fatigue strength continuously changing with materials strengthening can be obtained,as well as the maximum value of fatigue strength and corresponding critical yield *** summary,the Y-T-F model would be useful for reducing the fatigue tests,thus providing new possibilities on the efficient anti-fatigue design and selection of metallic materials.

关键词： Yield strength Tensile strength Plasticity Fatigue strength Anti-fatigue design

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Tensile ductility and deformation mechanisms of a nanotwinned 316L austenitic stainless steel

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journal of Materials Science & Technology 2020年第1期36卷 65-69页

作者： Y.z.zhang j.j.Wang N.R.Tao Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China University of Chinese Academy of Sciences Beijing 100049China

A nanotwinned 316 L austenitic stainless steel was prepared by means of surface mechanical grinding *** recovery annealing,the density of dislocations decreases obviously while the average twin/matrix lamella thickness still keeps in the nanometer *** annealed nanotwinned sample exhibits a high tensile yield strength of 771 MPa and a considerate uniform elongation of 8%.TEM observations showed that accommodating more dislocations and secondary twinning inside the nanotwins contribute to the enhanced ductility and work hardening rate of the annealed nanotwinned sample.

关键词： Nanotwinned Stainless steel Ductility Deformation mechanism

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A Mathematical Analysis of Scale Similarity

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Communications in Computational Physics 2017年第1期21卷 149-161页

作者： z.j.Wang Yanan Li Department of Aerospace Engineering University of Kansas2120 Learned HallLawrenceKS 66045USA

Scale similarity is found in many natural phenomena in the universe,from fluid dynamics to *** large eddy simulations of turbulent flows,some sub-grid scale(SGS)models are based on scale *** earliest scale similarity SGS model was developed by Bardina et al.,which produced SGS stresses with good correlation to the true *** the present study,we perform a mathematical analysis of scale *** analysis has revealed that the ratio of the resolved stress to the SGS stress is g2,where g is the ratio of the second filter width to the first filter width,under the assumption of small filter *** implications of this analysis are discussed in the context of large eddy simulation.

关键词： Scale similarity large eddy simulation sub-grid scale models

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Fatigue behavior of CoCrFeMnNi high-entropy alloy under fully reversed cyclic deformation

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journal of Materials Science & Technology 2019年第3期35卷 334-340页

作者： Y.z.Tian S.j.Sun H.R.Lin z.F.zhang Materials Fatigue and Fracture Division Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China

Bulk ultrafine-grained(UFG) CoCrFeMnNi high-entropy alloy(HEA) with fully recrystallized microstructure was processed by cold rolling and annealing treatment. The high-cycle fatigue behaviors of the UFG HEA and a coarse-grained(CG) counterpart were investigated under fully reversed cyclic *** fatigue strength of the UFG HEA can be significantly enhanced by refining the grain size. However,no grain coarsening was observed in the UFG HEA during fatigue tests. Mechanisms for the superior mechanical properties of the UFG HEA were explored.

关键词： High-entropy alloy(HEA) Ultrafine-grain(UFG) High-cycle fatigue Recrystallization Grain size Fatigue strength

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