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Journal of Magnesium and Alloys 2024年第4期12卷 1619-1637页

作者： yongbiao yang Jinxuan Guo Cuiying Wang Wenxuan Jiang Zhimin Zhang Qiang Wang Xing Zhang College of Materials Science and Engineering North University of ChinaLane 3Xueyuan RoadTaiyuanShanxi 030051China North Hongyang mechanical and electronic limited company of Henan Province China

Hot torsion tests for AZ80 magnesium alloy were carried out in the temperature range of 380℃-260℃,with a constant decreasing temperature rate of 10℃/s in order to weaken the basal texture and refine the grains.The results indicated that the average grain sizes were refined forming gradient structure with increasing specimen radial position from center(12.2-5.4μm),and that the initial basal texture intensity of the extruded magnesium alloy was weakened from 46.2 to 8.3.Furthermore,the extension twins(ETs)could be disintegrated from the twins forming separated twins with smaller sizes.Interestingly,ETs with the same twin variant intersecting with each other could be coalesced forming grains with similar orientation,while ETs with different twin variants were separated by twins boundaries contributing to grain refinement.Moreover,in addition to the conventional continuous dynamic recrystallized(CDRX)grains with 30˚orientation rotated around C-axis of the parent grains,CDRXed grains with 30˚rotation around a-axis and random rotation axis were also discerned.Besides,the CDRX evolution induced twins were also elaborated,exhibiting the complex competition between CDRX and twining.Hot torsion deformation with constant decreasing temperatures rate is an effective way of grain refinement and texture modification.

关键词： Texture Microstructure Hot torsion Decreasing temperature AZ80

The effects of deformation parameters and cooling rates on the aging behavior of AZ80+0.4%Ce

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Journal of Magnesium and Alloys 2024年第2期12卷 639-658页

作者： yongbiao yang Jinxuan Guo Cuiying Wang Ting Yan Zhang Wenxuan Jiang Zhimin Zhang Qiang Wang Guojun Li Jun Wang College of Materials Science and Engineering North University of ChinaLane 3Xueyuan RoadTaiyuanShanxiChina030051 State Key Laboratory of Advanced Stainless Steel Materials Taiyuan Iron Steel(Group)Co.Ltd.Taiyuan 030003China Technology Center Shanxi Taigang Stainless Steel Co.Ltd.Taiyuan 030003China

The extruded AZ80+0.4%Ce magnesium alloy was twisted in the temperature range of 300-380℃by using a Gleeble 3500 thermal simulation test machine with a torsion unit.The deformed cylindrical specimens were cooled at a cooling rate of 10℃/s or 0.1℃/s,respectively,and aged at 170℃.The microstructure analysis results showed that the grain size decreased with increasing specimen radial position from center(SRPC),and that the strong initial basal texture of the extruded magnesium alloy was weakened.Both continuous and discontinuous dynamic recrystallization mechanisms were involved in contributing to the grain refinement for all specimens investigated.And a novel extension twinning induced dynamic recrystallization mechanism was proposed for specimen deformed at 300℃.For the specimens deformed at 300℃and 340℃followed by a slow cooling rate(0.1℃/s),precipitates of various shapes(β-Mg_(17)Al_(12)),with the dominant precipitates being on the grains boundaries,appeared on the surface section.For specimen deformed at 380℃,lamellar precipitates(LPS)in the interiors of the grains were predominant.After aging,the LPS still dominated for specimens twisted at 380℃;however,the LPS gradually decreased with decreasing deformation temperatures from 380℃to 300℃.Dynamically precipitatedβ,especially those decorating the grain boundaries,changed the competition pictures for the LPS and precipitates of other shapes after aging.Interestingly,LPS dominated the areas for the center section of the specimens after aging regardless of deformation temperatures.Low temperature deformation with high SRPC followed by rapid cooling rate increased the micro hardness of the alloy after aging due to refined grain,reduced precipitates size,decreased lamellar spacing as well as strain hardening.

关键词： AZ80+0.4%Ce magnesium alloy Hot torsion Deformation parameters Cooling rate Aging Micro hardness

Reliability Assessment for Integrated Power-gas Systems Considering Renewable Energy Uncertainty and Cascading Effects

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CSEE Journal of Power and Energy Systems 2023年第3期9卷 1214-1226页

作者： Yucui Wang yongbiao yang Qingshan Xu School of Cyber Science and Engineering Southeast UniversityNanjing 210096China School of Electrical Engineering Southeast UniversityNanjing 210096China and Nanjing Center for Applied MathematicsNanjing 210096China

Integrated power-gas systems(IPGSs)make the power system and natural gas system(NGS)as a whole,and strengthen interdependence between the two systems.Due to bidirectional energy conversion in IPGS,a disturbance may turn into a catastrophic outage.Meanwhile,increasing proportion of renewable energy brings challenges to reliability of IPGS.Moreover,partial failure or degradation of system performance leads IPGS operate at multiple performance levels.Therefore,this paper proposes a reliability assessment model of IPGSs which represents multiple performance of components and considers cascading effects,as well as renewable energy uncertainty.First,a framework of IPGS reliability assessment is proposed:multistate models for main elements in the IPGS are represented.Especially a gas-power-generation calculation operator and a power-to-gas calculation operator are utilized to bi-directionally convert a multi-state model between NGS and power systems.Furthermore,nodal reliability indices for IPGS are given to display impacts of cascading effects and renewable energy uncertainty on reliabilities of IPGSs.Numerical results on IPGS test system demonstrate the proposed methods.

关键词： Cascading effects integrated power-gas systems multi-state model reliability renewable energy uncertainty

Community Integrated Energy System Trading:A Comprehensive Review

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1445-1458页

作者： Lu Chen Qingshan Xu yongbiao yang Hui Gao Weixiao Xiong College of Automation&College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Electrical Engineering Southeast UniversityNanjing 210096China

Focused on life,consumption,and leisure,communities have been regarded as the basic unit of energy use in a city owing to rapid urbanization,whose energy use density continues to increase.Moreover,community integrated energy systems(CIESs)in the rapid development stage have become embedded,small,and self-sufficient energy ecosystems within cities because of their environmental and economic benefits.CIESs face a competitive energy trading environment that comprises numerous entities and complicated relationships.This paper presents an extensive review of various issues related to CIES trading.First,the concepts,types,and resources of CIESs are described.Second,the trading patterns and strategies of CIESs are reviewed from the four perspectives of the trading objects:community-to-peer(C2P),peer-to-peer(P2P),community-to-community(C2C),and community-to-grid(C2G).Third,a tri-layer trading framework and the features of CIESs that participate in combined multienergy markets are proposed.Last,the key issues in CIES trading are summarized.

关键词： Distributed generation community integrated energy system multi-energy market trading pattern

用有限元模拟方法研究阶层式多孔薄膜几何参数对水通量的影响

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吉林大学学报（理学版） 2024年第3期62卷 721-727页

作者：卢婉杨永彪丁明明广东工业大学轻工化工学院广州510006 辽宁师范大学化学化工学院辽宁大连116029

通过系统改变阶层式多孔薄膜大孔和小孔的孔径及孔隙率等几何参数,用有限元模拟方法研究薄膜通量与相关几何参数之间线性或非线性的定量关系.模拟结果表明,在弯曲孔道基体中添加球形空穴形成阶层式多孔结构后,可使薄膜水通量提升约为原... 详细信息

通过系统改变阶层式多孔薄膜大孔和小孔的孔径及孔隙率等几何参数,用有限元模拟方法研究薄膜通量与相关几何参数之间线性或非线性的定量关系.模拟结果表明,在弯曲孔道基体中添加球形空穴形成阶层式多孔结构后,可使薄膜水通量提升约为原来的171%.对于弯曲孔道,单纯增加其数量可使水通量线性提升,单纯增大其孔径可使水通量以指数函数形式提升.对于球形空穴,单纯增加其数量或单纯增大其孔径,水通量均以指数函数形式提升.此外,球形空穴的水通量提升作用还依赖于它与弯曲孔道基体网格的相对尺寸,通过调节制备条件可提升分离膜材料的性能.

关键词：阶层式多孔膜膜通量有限元模拟

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Time series modeling and filtering method of electric power load stochastic noise

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Protection and Control of Modern Power Systems 2017年第1期2卷 269-275页

作者： Li Huang yongbiao yang Honglei Zhao Xudong Wang Hongjuan Zheng NARI Technology Development CO. LtdNanjingJiangsu Province 211106China. State Grid Tianjin Electric Power Company Tianjin 300010China.

Stochastic noises have a great adverse effect on the prediction accuracy of electric power load.Modeling online and filtering real-time can effectively improve measurement accuracy.Firstly,pretreating and inspecting statistically the electric power load data is essential to characterize the stochastic noise of electric power load.Then,set order for the time series model by Akaike information criterion(AIC)rule and acquire model coefficients to establish ARMA(2,1)model.Next,test the applicability of the established model.Finally,Kalman filter is adopted to process the electric power load data.Simulation results of total variance demonstrate that stochastic noise is obviously decreased after Kalman filtering based on ARMA(2,1)model.Besides,variance is reduced by two orders,and every coefficient of stochastic noise is reduced by one order.The filter method based on time series model does reduce stochastic noise of electric power load,and increase measurement accuracy.

关键词： Electric power load Stochastic noise ARMA model Kalman filter

基于随机森林算法的综合能源配电网电能质量评估方法与网架优化模型

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电测与仪表 2024年第5期61卷 17-23页

作者：李海涛崔树春尹华薛小川张磊杨永标国网江苏省电力有限公司淮安供电分公司江苏淮安223001 东南大学电气工程学院南京210000

文中针对综合能源配电网存在的电能质量问题考虑采用网架优化措施进行优化。对计及电压偏差、谐波电压、电压波动、三相不平衡度四个指标采用层次分析法建立综合能源配电网电能质量评估体系,其中基于模糊层次分析法确定评估体系各指标... 详细信息

文中针对综合能源配电网存在的电能质量问题考虑采用网架优化措施进行优化。对计及电压偏差、谐波电压、电压波动、三相不平衡度四个指标采用层次分析法建立综合能源配电网电能质量评估体系,其中基于模糊层次分析法确定评估体系各指标的主观权重,以综合能源配电网网架优化方案为控制变量,考虑到系统中多种能源形式的互补运行,以配电网电能质量评估指标最大化为目标函数,计及配电网网络拓扑约束,节点电压约束,网络辐射状约束等必要约束条件建立配电网网架重构优化模型。针对随机森林算法分析其运行原理,并基于随机森林算法对所建立的模型设计模型求解流程,进行仿真算法分析,说明所建立的模型能够改进配网电能质量,验证了模型的正确性和有效性。

关键词：配电网电能质量评估模糊层次分析网络重构优化随机森林算法

Middle Permian palaeobiogeography study in East Kunlun,A'nyêmaqên and Bayan Har

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Science China Earth Sciences 2004年第12期47卷 1120-1126页

作者： WANG yongbiao yang Hao Faculty of Earth Science China University of Geosciences Wuhan 430074 China Faculty of Earth Science China University of Geosciences Wuhan 430074 China

Three regions can easily be identified in the study area according to the Middle Permian palaeobiogeographic distribution of biota, they are the southern slope of East Kunlun, A’nyêmaqên and Bayan Har. Biotic constitution and ecology in the southern slope of East Kunlun and Bayan Har are very similar. Both the diversity and abundance of organisms in these two areas are very high and reefs are widely developed. However, biotic diversity and abundance in A’nyêmaqên which is between the above two areas are obviously low. Differentiation of palaeo- biogeographic distribution in these areas should be due to the baring of A’nyêmaqên ocean in the time of Middle Permian. Middle Permian radiolarian chert and thick abyssal red ooze are widely spread in A’nyêmaqên, implying that the A’nyêmaqên ocean had a great scale in size. Vast scale of deep ocean basin became an impassable gulf for some of the benthos, and as a result, only part of the organisms could have the chance to get to the isolated islands situated in ocean basin. Small living space and hard conditions in the islands further limited the abundance and diversity of biota. Tectonic background reflected by the geochemical study of basalt in the three areas is coupling well enough with the palaeobiogeographic division.

关键词： palaeobiogeography, Middle Permian, East Kunlun, A'nyêmaqên, Bayan Har.

Phase separation of S-RNase promotes self-incompatibility in Petunia hybrida

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Journal of Integrative Plant Biology 2024年第5期66卷 986-1006页

作者： Huayang Tian Hongkui Zhang Huaqiu Huang Yu'e Zhang yongbiao Xue The State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental Biologythe Chinese Academy of SciencesBeijing 100101China University of the Chinese Academy of Sciences Beijing 100049China Beiing Institute of Genomics Chinese Academy of SciencesNational Center for BioinformationBeijing 100101China

Self-incompatibility(SI)is an intraspecific reproductive barrier widely present in angiosperms.The SI system with the broadest occurrence in angiosperms is based on an S-RNase linked to a cluster of multiple S-locus F-box(SLF)genes found in the Solanaceae,Plantaginaceae,Rosaceae,and Rutaceae.Recent studies reveal that non-self S-RNase is degraded by the Skip Cullin F-box(SCF)SLF-mediated ubiquitin–proteasome system in a collaborative manner in Petunia,but how self-RNase functions largely remains mysterious.Here,we show that S-RNases form S-RNase condensates(SRCs)in the self-pollen tube cytoplasm through phase separation and the disruption of SRC formation breaks SI in self-incompatible Petunia hybrida.We further find that the pistil SI factors of a small asparagine-rich protein HT-B and thioredoxin h together with a reduced state of the pollen tube all promote the expansion of SRCs,which then sequester several actin-binding proteins,including the actin polymerization factor PhABRACL,the actin polymerization activity of which is reduced by S-RNase in vitro.Meanwhile,we find that S-RNase variants lacking condensation ability fail to recruit PhABRACL and are unable to induce actin foci formation required for pollen tube growth inhibition.Taken together,our results demonstrate that phase separation of S-RNase promotes SI response in P.hybrida,revealing a new mode of S-RNase action.

关键词： self-incompatibility S-RNase phase separation

Multilevel carbon architecture of subnanoscopic silicon for fast‐charging high‐energy‐density lithium‐ion batteries

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Carbon Energy 2024年第4期6卷 256-268页

作者： Meisheng Han yongbiao Mu Lei Wei Lin Zeng Tianshou Zhao Shenzhen Key Laboratory of Advanced Energy Storage Southern University of Science and TechnologyShenzhenChina SUSTech Energy Institute for Carbon Neutrality Southern University of Science and TechnologyShenzhenChina Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhenChina

Silicon(Si)is widely used as a lithium‐ion‐battery anode owing to its high capacity and abundant crustal reserves.However,large volume change upon cycling and poor conductivity of Si cause rapid capacity decay and poor fast‐charging capability limiting its commercial applications.Here,we propose a multilevel carbon architecture with vertical graphene sheets(VGSs)grown on surfaces of subnanoscopically and homogeneously dispersed Si–C composite nanospheres,which are subsequently embedded into a carbon matrix(C/VGSs@Si–C).Subnanoscopic C in the Si–C nanospheres,VGSs,and carbon matrix form a three‐dimensional conductive and robust network,which significantly improves the conductivity and suppresses the volume expansion of Si,thereby boosting charge transport and improving electrode stability.The VGSs with vast exposed edges considerably increase the contact area with the carbon matrix and supply directional transport channels through the entire material,which boosts charge transport.The carbon matrix encapsulates VGSs@Si–C to decrease the specific surface area and increase tap density,thus yielding high first Coulombic efficiency and electrode compaction density.Consequently,C/VGSs@Si–C delivers excellent Li‐ion storage performances under industrial electrode conditions.In particular,the full cells show high energy densities of 603.5 Wh kg^(−1)and 1685.5 Wh L^(−1)at 0.1 C and maintain 80.7%of the energy density at 3 C.

关键词： fast charging high energy densities lithium‐ion batteries multilevel carbon architecture subnanoscopic silicon anode