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High-temperature strength-coercivity balance in a FeCo-based soft magnetic alloy via magnetic nanoprecipitates

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Journal of Materials Science & Technology 2021年第22期81卷 36-42页

作者： Kaisheng Ming Shuimiao Jiang Xiaoyuan Niu Bo Li Xiaofang Bi Shijian zheng State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjin300130China Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology School of Materials Science and EngineeringHebei University of TechnologyTianjin300130China Key Laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and EngineeringBeihang UniversityBeijing100191China School of Chemical Engineering and Technology Hebei University of TechnologyTianjin300130China

Precipitation strengthening is an effective approach to enhance the strength of soft magnetic alloys for applications at high temperatures,while inevitably results in deterioration in coercivity due to the pinning effect on the domain wall ***,we realize a good combination of high-temperature strength and ductility(ultimate tensile strength of 564 MPa and elongation of~20%,respectively)as well as low coercivity(6.97 Oe)of FeCo-2V-0.3Cr-0.2Mo soft magnetic alloy through introducing high-density magnetic *** magnetic nanoprecipitates are characterized by FeCo-based phase with disordered body-centered cubic structure,which enables the alloy to have a low *** addition,these nanoprecipitates can impede the dislocation motion and suppress the brittle fracture,which lead to a high tensile strength and *** work provides a guideline to enhance strength and ductility while maintaining low coercivity in soft magnetic alloys via magnetic nanoprecipitates.

关键词： FeCo-based soft magnetic alloys Strength Ductility Coercivity Magnetic nanoprecipitates

What and where: A context-based recommendation system for object insertion

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Computational Visual Media 2020年第1期6卷 79-93页

作者： Song-Hai Zhang zheng-Ping Zhou Bin Liu Xi Dong Peter Hall Tsinghua University Beijing 100084China Beijing National Research Center for Information Science and Technology(BNRist) Tsinghua UniversityBeijing 100084China Department of Computer Science Media Technology Research Center University of BathBath BA27AYUK

We propose a novel problem revolving around two tasks:(i)given a scene,recommend objects to insert,and(ii)given an object category,retrieve suitable background scenes.A bounding box for the inserted object is predicted in both tasks,which helps downstream applications such as semiautomated advertising and video *** major challenge lies in the fact that the target object is neither present nor localized in the input,and furthermore,available datasets only provide scenes with existing *** tackle this problem,we build an unsupervised algorithm based on object-level contexts,which explicitly models the joint probability distribution of object categories and bounding boxes using a Gaussian mixture *** on our own annotated test set demonstrate that our system outperforms existing baselines on all sub-tasks,and does so using a unified *** extensions and applications are suggested.

关键词： object recommendation bounding box prediction image composition object-level context

Electron transfer dynamics in Schottky junction photocatalyst during electron donor-assisted hydrogen production

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Journal of Materials Science & Technology 2023年第28期159卷 1-9页

作者： Jianjun Zhang Jingjing Liu zheng Meng Sanjib Jana Linxi Wang Bicheng Zhu Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of Geosciences68 Jincheng StreetWuhan 430078China School of Chemistry Chemical Engineering and BiotechnologyNanyang Technological University21 Nanyang LinkSingapore 637371Singapore Jiangxi Key Laboratory of Surface Engineering Jiangxi Science and Technology Normal UniversityNanchang 330038China

Electron donors(EDs)are widely used to improve the H 2 production performance of Schottky junction photocatalysts,but the functions of EDs are still unknown from the perspective of electron transfer ***,Pt nanocluster-decorated CdS nanorod is successfully prepared to construct a typical CdS/Pt Schottky *** nanoclusters with a diameter of∼2 nm are deposited on the surface of CdS nanorods by in situ photoreduction at sub-zero *** CdS/Pt photocatalyst using lactic acid shows a higher H_(2)production rate of 4762μmol g^(-1)h^(-1)compared to that using methanol,tri-ethanolamine,and *** understand the cause,the dynamics of photogenerated carriers in CdS/Pt photocatalysts during ED-assisted H_(2)production are revealed by femtosecond transient absorption *** the four organic EDs,lactic acid enables the fastest electron transfer rate of 1.8×10^(9)s^(-1)and the highest electron transfer efficiency of 76%at the CdS/Pt interface due to the most efficient hole *** work sheds light on the importance of efficient interfacial electron transfer for im-proving the photocatalytic performance of Schottky junction photocatalysts.

关键词： Transient absorption spectroscopy Interfacial electron transfer Electron transfer rate Electron transfer efficiency Hole consumption

NbB_(2)Modified Al-Cu Alloys Fabricated by Freeze-Ablation Casting under High Cooling Rate Solidification

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 921-938页

作者： Xiang Kong Yu Wang Hong Xu Haotian Fan Yuewu zheng Beibei Xie School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

At present,improving the properties of aluminum alloys is generally achieved by increasing the cooling rate of the melt and adding micro-nano *** the cooling rate of the melt to improve the refining effect of grain refiner is still a difficult problem in the aluminum alloy casting *** innovative and environmentally friendly casting process,known as freeze ablation,was introduced during the preparation of an Al–NbB_(2) intermediate *** process significantly enhanced the cooling rate of the *** results indicated that the Al–NbB_(2) intermediate alloy produced under high cooling rates had a noticeable refining effect on Al–Cu alloys,with smaller NbB2 particles demonstrating superior refining *** average grain size of the refined Al–Cu alloy decreased from 154 to 69μm,the tensile strength increased by 12%,the fluidity increased by 18.4%,and the hot tearing index decreased from 144 to *** matching degree between NbB_(2) andα-Al was calculated using high-resolution transmission electron microscopy and the edge-to-edge *** was found that the atomic interplanar spacing and the interatomic spacing mismatch between NbB_(2)’splane and Al were both less than 10%,which further proved that NbB2 could serve as an effective nucleation site forα-Al grains to achieve grain refinement.

关键词： Grain refinement Freeze ablation Particle size control Mechanical properties Process properties

The Concept and Theoretical Implications of Carbon Emissions Rights Based on Individual Equity

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Chinese Journal of Population,Resources and Environment 2011年第2期9卷 39-53页

作者： Pan Jiahua zheng Yan Institute of Urban and Environmental Studies Chinese Academy of Social Sciences Beijing 100005 China

Climate change has become a hot topic in international environmental *** post-Kyoto international climate regime negotiations,many countries have proposed a variety of frameworks to share the emission reduction responsibilities and allocate carbon emission rights,and have tried to quantify the emission reduction obligations of all countries based on the perspectives of international equity and individual *** this paper,the authors have distinguished the concepts of carbon emissions rights based on these two perspectives respectively,have analyzed the relationship between carbon emissions per capita and economic development,and have calculated and compared the proportion of cumulative emissions per capita of different countries in history and future,and then authors conclude that emission reduction obligations should be allocated based on each country's conditions,including historical emissions,development stage,and future *** countries should take the initiative to significantly reduce their emissions because they have already accomplished their industrialization ***,developing countries are still in the process of industrialization,which requires more emission rights to meet their development *** China,the concept of carbon emissions based on individual equity can be used as a theoretical tool for the allocating the international carbon emissions rights.

关键词： carbon emissions per capita cumulative carbon emissions per capita responsibility in mitigation basic needs for human development

Distributed Cooperative Current-Sharing Control of Coupled Parallel Charging Systems with Super-Capacitor Loads 36

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Distributed Cooperative Current-Sharing Control of Coupled P...

Study on the influence mechanism of ambient humidity on the temperature rise of decay-like composite insulators

第36届中国控制会议

作者： Jiangang Liu Zhiqiang zheng School of Mathematics and Statistics Hunan University of Commerce School of Mechatronics Engineering and Automation National University of Defense Technology

ISBN: (纸本)9781538629185

In order to address the output current imbalanced problem of parallel chargers for energy storage type lignt rail vehicles,a distributed cooperative current-sharing scheme is proposed in this *** each charger as an agent,the current-sharing control design can be modeled as the output current consensus-tracking problem of nonlinear and non-identical multi-agent systems with the bounded control *** communication topology between each parallel charger is modeled a directed graph,which only needs a spanning *** order to guarantee the boundedness of the control input,a general saturation function is introduced into the control *** distributed cooperative PID current-sharing controller is designed based on the nearest neighborhood *** system stability and dynamic performance of the proposed cooperative control scheme is evaluated by analyzing the transfer function matrix from the input duty ratio to the output *** the physical parameters and communication topology of the parallel chargers are given in advance,the system stability can be maintained by choosing the proportional,integral and derivative control *** output current of parallel chargers can be balanced by adopting the proposed approach,which is verified by simulating a parallel charging test system.

关键词： Current-Sharing Control Parallel Chargers Multi-Agent Systems Cooperative PID Control

来源： cnki会议评论

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High Voltage 2022年第5期7卷 916-924页

作者： zheng Zhong Yuan Chen Yunpeng Liu Sizu Hou Jianghai Geng Hebei Key Laboratory of Power Transmission Equipment Security Defense North China Electric Power UniversityBaodingChina High Voltage Technology Institute North China Electric Power Research InstituteBeijingChina Hebei Key Laboratory of Power Internet of Things Technology North China Electric Power UniversityBaodingChina

At present,observing the temperature rise of composite insulators is an effective method for the detection of decay-like ***,ambient humidity will affect the temperature rise of composite insulators,which will cause problems in screening the decaylike composite ***,it is urgent to study the temperature rise principle of decay-like insulators and find out the influence mechanism of humidity on temperature *** this study,a four-electrode system is designed to measure the surface current,volume current and interface current of the decay-like short sample and the intact short sample under different *** the equivalent circuit models of short samples and the 500 kV full-size decay-like composite insulator are built to analyse the contribution rates of leakage conductance loss and polarisation loss to temperature *** results show that the contribution rates of the polarisation loss to the temperature rise of two samples are 35.8%and 23.6%in low humidity,while they are 98.3%and 64.4%in high *** the full-size decay-like composite insulator,the contribution rates of polarisation loss to its temperature rise in high or low humidity are more than 99%.In addition,the proportion of polarisation loss increases at first and then decreases with the increase of the length of the decay-like *** conclusions of this study provide a theoretical basis for further understanding the corresponding relationship between decaylike defects and temperature rise and improve the detection rate of decay-like insulators.

关键词： composite ambient humidity

A Modular Synthesis of Antitumor Macrolide (-)-Lasonolide A

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Chinese Journal of Chemistry 2020年第7期38卷 725-736页

作者： Lin Yang Zuming Lin Kuan zheng Luyao Kong Ran Hong CAS Key Laboratory of Synthetic Chemistry of Natural Substances Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling RoadShanghai 200032China University of Chinese Academy of Sciences 19A Yuquan RoadBeijing 100049China

Lasonolide A was identified as a potent antitumor macrolide towards various cancer cell *** two tetrahydropyrans bearing multiple stereogenic centers as well as the polyvene linkage attracted a dozen synthetic research groups to launch the total *** on the synthetic methods developed in our group,namely,the hydroboration of allene and its subsequent allylation as well as the iterative hydroboration of allene and oxidation,the polyol subunits were efficiently constructed and then integrated into the final target.A new Julia olefination reagent,double-headed sulfone,was designed to promote the rapid coupling of two aldehydes bearing multiple functional groups to secure the whole carbon *** highlight of our approach is the application of a traceless protecting group,9-BBN(9-borabicyclo[3.3.1]nonane),to hide the secondary alcohol for debenzylation,and for the first time,to mask the carboxylic acid for Julia olefination under strong basic conditions.

关键词： aldehydes linkage reagent

Dissecting the brain with spatially resolved multi-omics

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Journal of Pharmaceutical Analysis 2023年第7期13卷 694-710页

作者： Yijia Fangma Mengting Liu Jie Liao Zhong Chen Yanrong zheng Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province School of Pharmaceutical SciencesZhejiang Chinese Medical UniversityHangzhou310053China Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang UniversityHangzhou310058China

Recent studies have highlighted spatially resolved multi-omics technologies,including spatial genomics,transcriptomics,proteomics,and metabolomics,as powerful tools to decipher the spatial heterogeneity of the ***,we focus on two major approaches in spatial transcriptomics(next-generation sequencing-based technologies and image-based technologies),and mass spectrometry imaging technologies used in spatial proteomics and spatial ***,we discuss their applications in neuroscience,including building the brain atlas,uncovering gene expression patterns of neurons for special behaviors,deciphering the molecular basis of neuronal communication,and providing a more comprehensive explanation of the molecular mechanisms underlying central nervous system ***,further efforts are still needed toward the integrative application of multi-omics technologies,including the real-time spatial multi-omics analysis in living cells,the detailed gene profile in a whole-brain view,and the combination of functional verification.

关键词： Central nervous system disorders Multi-omics Spatial transcriptomics Spatial proteomics Spatial metabolomics