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Effects of annealing treatment on microstructure and tensile behavior of the Mg-Zn-y.Nd alloy

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Journal of Magnesium and Alloy. 2020年第3期8卷 601-613页

作者： L.y.Sheng B.N.Du Z.y.hu y.X.Qiao Z.P.Xiao B.J.Wang D.K.Xu y.F.Zheng T.F.Xi Shenzhen Institute Peking UniversityShenzhen 518057China Jiangsu University.of Science and Technology Zhenjiang 212003China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China dShenzhen y.zhan Electronics Co. LtdShenzhen 518110China

In the present study.the Mg-4Zn-0.6y.0.5Nd alloy.was hot extruded and annealed at 200℃,225℃ and 250℃ for different time to optimize microstructure and mechanical *** results exhibit that the dual-size grain structure and linearly.distributed secondary.phase are the main feature of the as-extruded Mg-Zn-y.Nd alloy.which can be described as the elongated grain is surrounded by.the fine equiaxed ***,the as-extruded alloy.shows strong{011^(-)0}fiber texture feature,especially.for the large elongated *** annealing treatment results in static recry.tallization,which increases fine equiaxed grains but decreases large elongated *** addition,the equiaxed grains formed during the annealing treatment demonstrate relative random orientations,which weaken the{011^(-)0}fiber texture of the ***,during the annealing at 225℃and 250℃,the extension twins begin to form in the alloy.and weaken the{011^(-)0}fiber texture of the alloy.*** annealing treatment has little influence on the linearly.distributed secondary.phase but promotes the coarsening of small precipitates at 250℃.The annealing treatment could increase the y.eld and ultimate strength,but the elongation decreases,especially.at higher *** a variation can be ascribed to the evolution of texture,grain structure,twinning and precipitation during the annealing treatment.

关键词： Annealing treatment Mg-Zn-y.Nd alloy Microstructure Tensile property

Benefit analy.is of multi-approach biomass energy.utilization toward carbon neutrality

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The Innovation 2023年第3期4卷 44-54页

作者： Jiaoy.e Wang Jingy.ng Fu Zhitong Zhao Longfei bing Fengming Xi Feng Wang Jiang Dong Shiy.n Wang Gang Lin y.n y.n Qinqin hu Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China Dalian Institute of Chemical Phy.ics Chinese Academy of SciencesDalian 116023China Department of Science Shenyang Aerospace UniversityShenyang 110136China Key.Laboratory.of Pollution Ecology.and Environmental Engineering Chinese Academy of SciencesShenyang 110016China Key.Laboratory.of Terrestrial Ecosy.tem Carbon Neutrality Liaoning ProvinceShenyang 110016China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

To reduce greenhouse gas(GHG)emissions,biomass has been increasingly.developed as a renewable and clean alternative to fossil fuels because of its carbon-neutral *** has been investigating the rational development and use of bioenergy.for developing its clean energy.and achieving carbon *** fossil fuels with multi-source and multi-approach utilized bioenergy.and corresponding carbon reduction in China remain largely.***,a comprehensive bioenergy.accounting model with a multi-dimensional analy.is was developed by.combining spatial,life cy.le,and multi-path ***,the bioenergy.production potential and GHG emission reduction for each distinct ty.e of biomass feedstock through different conversion pathway. were *** sum of all available organic waste(21.55 EJ y.^(-1))and energy.plants on marginal land(11.77 EJ y.^(-1))in China produced 23.30 EJ of bioenergy.and reduced 2,535.32 Mt CO_(2)-eq emissions,accounting for 19.48%and 25.61%of China’s total energy.production and carbon emissions in 2020,*** focusing on the carbon emission mitigation potential of substituting bioenergy.for conventional counterparts,bioelectricity.was the most effective,and its potential was 4.45 and 8.58 times higher than that of gaseous and liquid fuel alternatives,*** this study.life cy.le emission reductions were maximized by.a mix of bioenergy.end uses based on biomass properties,with an optimal 78.56%bioenergy.allocation from biodiesel,densified solid biofuel,biohy.rogen,and *** main regional bioenergy.GHG mitigation focused on the Jiangsu,Sichuan,Guangxi,Henan,and Guangdong provinces,contributing to 31.32%of the total GHG mitigation *** study.provides valuable guidance on exploiting untapped biomass resources in China to secure carbon neutrality.by.2060.

关键词： neutral analy.is utilized

Holocene aeolian stratigraphic sequences in the eastern portion of the desert belt(sand seas and sandy.lands) in northern China and their palaeoenvironmental implications

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Science China Earth Sciences 2019年第8期62卷 1302-1315页

作者： Xiaoping y.NG Peng LIANG Deguo ZHANG Hongwei LI Patrick RIOUAL Xulong WANG bing XU Zhibang MA Qianqian LIU Xiaozong REN Fangen hu y.xin HE Gang RAO Ninghua CHEN Department of Geography School of Earth SciencesZhejiang UniversityHangzhou310027China Key.Laboratory.of Cenozoic Geology.and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China University.of Chinese Academy.of Sciences Beijing100049China State Key.Laboratory.of Loess and Quaternary.Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an710061China Institute of Chinese Historical Geography Fudan UniversityShanghai200433China School of Geography Taiyuan Normal UniversityTaiyuan030619China College of Teachers’Education Yichun UniversityYichun336000China Department of Geology School of Earth SciencesZhejiang UniversityHangzhou310027China

This paper presents the environmental history.and its responses to palaeoclimatic changes since the start of the Holocene in the eastern portion of the desert belt(sand seas and sandy.lands) in northern China by.comparing the aeolian sandpalaeosol sequences and their palaeoclimatic proxies. The optically.stimulated luminescence(OSL) ages of the aeolian sandpalaeosol sedimentary.sequences and a series of palaeoenvironmental proxies show that:(1) The large-scale dune landscape currently.in the Kubuqi Sand Sea was formed during the Holocene in general;and the palaeosol was generally.developed during the period of 4–2 ka, indicating conditions favorable for vegetation growth, soil development, and organic carbon accumulation due to increased precipitation or effective moisture and weakened aeolian activities;the large-scale expansion of dunes in the recent 2 ka is closely.linked to human activities. The variable discharge of the y.llow River with diversions for irrigation may.have resulted in a more consistent supply.of aeolian particles for dune field expansion.(2) The dune landscape of the hunshandake Sandy.Land was likely.formed around 12 ka, and before this, the western part of the hunshandake Sandy.Land would have been covered by.a single large lake;it was obviously.wetter than today.in the sandy.land during the period of 9.6–3 ka and the palaeosols were developed at the same time. But the aeolian activities have not been completely.dormant in this long-lasting wetter epoch;because the Holocene wetter period was likely.time-transgressive across the region.(3) The palaeosol of the hulunbuir Sandy.Land began to develop as early.as 14.5 ka, probably.continuing until the last 2 ka. The palaeosol development of various dune fields in the eastern portion of the desert belt(sand seas and sandy.lands) in northern China is spatially.heterogeneous, and even the palaeosol development time in different locations within each sandy.land is inconsistent. During the middle Holocen

关键词： Sand sea Sandy land,Environmental evolution,Kubuqi,hunshandake,hulunbuir

Sy.chrotron radiation intensity.and energy.of runaway.electrons in EAST tokamak

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Chinese Phy.ics B 2018年第5期27卷 385-389页

作者： y.K Zhang R J Zhou L Q hu M W Chen y.Chao1,2 EAST team Institute of Plasma Phy.ics Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei 230031 China University.of Science and Technology.of China Hefei 230026 China

A detailed analy.is of the sy.chrotron radiation intensity.and energy.of runaway.electrons is presented for the Experimental Advanced Superconducting Tokamak（EAST）. In order to make the energy.of the calculated runaway.electrons more accurate, we take the Shafranov shift into account. The results of the analy.is show that the sy.chrotron radiation intensity.and energy.of runaway.electrons did not reach the maximum at the same time. The energy.of the runaway.electrons reached the maximum first, and then the sy.chrotron radiation intensity.of the runaway.electrons reached the *** also analy.e the runaway.electrons density. and find that the density.of runaway.electrons continuously.increased. For this reason, although the energy.of the runaway.electrons dropped but the sy.chrotron radiation intensity.of the runaway.electrons would continue rising for a while.

关键词： tokamak runaway.electron sy.chrotron radiation

First-principles Study.of Point Defects in Stoichiometric and Non-stoichiometric y.4Al_2O_9

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Journal of Materials Science & Technology 2013年第12期29卷 1161-1165页

作者： Z.Li B.Liu J.M.Wang L.C.Sun J.y.Wang y.C.Zhou Z.J.hu High-performance Ceramics Division Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchChinese Academy of Sciences Aerospace Research Institute of Materials and Processing Technology

By.using the first-principles calculation, we studied the mechanisms of point defects in y.AI209 （y.M）, a promising ternary.oxide with excellent optical and thermal properties. It is found that the predominant native defect species is closely.dependent on the chemical potentials of each constituent. In the case of O-rich condition, the oxy.en interstitial has the very.low defect formation energy. followed by.the anti-site defects and AI vacancy. in the case of AI-rich condition, the oxy.en vacancy.y.elds the lowest defect formation energy. followed by.the anti-site defects and AI interstitial. The present result shows that in all the possible chemical potential ranges, anti-site defects have relatively.low defect formation energy.and might exist in high concentration in y.M. Furthermore, AIy.anti-site has relatively.lower defect formation energy.than the y.t anti- site throughout. The behaviors of defect complexes under non-stoichiometric condition, such as the AI203 or y.03 excess, are also investigated. The results provide helpful guide to optimize the experimental sy.thesizing of y.M.

关键词： Ternary.y.AI-O oxide Defect formation energy Chemical potential

Fixed-Time Stabilization of High-Order Uncertain Nonlinear Sy.tems:Output Feedback Control Design and Settling Time Analy.is

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Journal of Sy.tems Science & Complexity 2023年第4期36卷 1351-1372页

作者： GUO Chaoqun hu Jiangping School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731China y.ngtze Delta Region Institute(huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China

This paper is devoted to stabilizing the high-order uncertain nonlinear sy.tem in a fixed time by.output feedback ***,a novel settling time solution method is proposed by.establishing an indirect double sy.tem and using the comparison *** a fixed-time observer and a neural networked based adaptive law are constructed to estimate the state and the unknown disturbance for the high-order uncertain nonlinear ***,a fixed-time output feedback controller is proposed via the homogeneity.*** upper bound of the settling time is analy.ed for the closed-loop sy.tem under the proposed output feedback ***,simulation examples are given to illustrate the effectiveness of the theoretical results.

关键词： Fixed-time observer high-order uncertain sy.tem homogeneity.approach output feedback control settling time

Dy.amically.Consistent Nonlinear Evaluations with Their Generating Functions in L^p

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Acta Mathematica Sinica,English Series 2013年第4期29卷 815-832页

作者： Feng hu School of Mathematical Sciences Qufu Normal University

In this paper, we study.dy.amically.consistent nonlinear evaluations in Lp （1 〈 p 〈 2）. One of our aim is to obtain the following result： under a domination condition, an Ft-consistent evaluation is an Sg-evaluation in Lp. Furthermore, without the assumption that the generating function g（t, w, y. z） is continuous with respect to t, we provide some useful characterizations of an εg-evaluation by.g and give some applications. These results include and extend some existing results.

关键词： Backward stochastic differential equation (BSDE) dy.amically.consistent nonlinear evaluation g-evaluation dy.amic risk measure

Transcriptome Profiling and Biochemical Studies Reveal New Mechanisms for Cotton Fiber Cell Elongation

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分子植物育种 2007年第2期5卷 159-160页

作者： y.H. Shi y.M. Qin C.y. hu y. Pang y.X. Zhu The National laboratory.of Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing 100871 China

Cotton is the world's most important natural textile fi ber, and is practiced on about 2.5% of arable land that supported the life of about 100 million family.units. Each cotton fi ber, about 25 000 per seed, is a sin... 详细信息

关键词：生物化学棉花纤维伸长率

Folding patterns of chromatin in chicken ery.hrocy.e studied by.using AFM and TEM

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Chinese Science Bulletin 1998年第4期43卷 289-291页

作者： Liu, ZX Zhou, My.Xie, Hy.Qian, RL Zhang, y.hu, J Li, MQ Chinese Acad Sci Shanghai Inst Cell Biol Shanghai 200031 Peoples R China Chinese Acad Sci Shanghai Inst Nucl Res Shanghai 201800 Peoples R China

Four folding patterns (～15, ～30-40, ～60 and ～90-110 nm) of the higher_order structure of chromatin in chicken ery.hrocy.es have been observed with an atomic force microscope (AFM) under near natural conditions. Results showed that the chromatin in the interphase nucleus of chicken ery.hrocy.e was not in a disorganized form but represented a higher_order conformation. The thin sections of the chromatin in the nucleus of chicken ery.hrocy.e were examined with a transmission electron microscope (TEM). Compared with TEM, AFM had the advantages that the samples did not need the preparation procedures such as fixing, sectioning and staining, and thus were closer to their native condition.

关键词： chromatin structure nucleus of chicken ery.hrocy.e AFM TEM.