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Soft-Magnetic High-Entropy AlcoFeMnNi Alloys with Dual-Phase Microstructures Induced by Annealing

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Acta Metallurgica Sinica(English Letters) 2020年第8期33卷 1124-1134页

作者： chengbo Yang Jing zhang Meng Li Xuejian Liu college of Materials Science and Engineering Chongqing UniversityChongqing 400044China Guangdong Institute of Materials and Processing Guangzhou 510650China

The simultaneous enhancement of magnetic and mechanical properties is desirable but challenging for soft-magnetic materials.A fabrication strategy to meet this requirement is therefore in high ***,bulk equiatomic dual-phase AlcoFeMnNi high-entropy alloys were fabricated via a magnetic levitation induction melting and casting process followed by annealing at 700-1000℃,and their microstructures as well as mechanical and magnetic properties were *** as-cast alloy possessed a single metastable b2-ordered solid solution that decomposed upon annealing into a dual-phase structure comprising an Al-and Ni-rich body-centered c.b.c.b.c)matrix and Fe-and Mn-rich face-centered c.b.c(Fcc)precipitates both in the grain interior and along the grain *** magnetic and mechanical properties were closely related to the relative volume fraction of Fcc in the *** Fcc volume fraction could be increased by increasing the annealing temperature,thereby offering tunable *** optimal annealing temperature for balanced magnetic and mechanical properties was found to be 800℃.The alloy annealed at this temperature had an average bcc grain size of 12±3μm and Fcc volume fraction of 41±4%.correspondingly,the s aturation magnetization and coercivity reached 82.57 Am^2/kg and 433 A/m,*** compressive yield strength and fracture strength were 1022 and 2539 MPa,respectively,and the plasticity was 33%.Owing to its adjustable microstructure and properties,the AlcoFeMnNi alloy has potential for use as a multi-functional soft-magnetic material.

关键词： High-entropy alloy Microstructure Phase transformation Soft-magnetic material Precipitation

Missing for partnership: understanding nucleosomal de novo DNA cytosine methylation by a spliced DNMT3 complex

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Signal Transduction and Targeted Therapy 2021年第2期6卷 209-210页

作者： Min zhang Haitao Li MOE Key Laboratory of Protein Sciences Beijing Advanced Innovation Center for Structural BiologyTsinghua-Peking Center for Life SciencesSchool of MedicineTsinghua UniversityBeijingChina

In a recent paper published in Nature,Xu et *** a cryo-EM structure of a,spliced,de novo DNA methyltransferase complex,DNMT3A2-DNMT3b3,bound to a mono-nucleosome with extended linker DNA.1 Reinforced by biochemical assays and genomic studies,this structure reveals the molecular mechanism underlying de novo cytosine methylation on nucleosomal ***,the catalytically inactive DNMT3b3 occupies the nucleosome core and orients the active DNMT3A2 to target the linker DNA as its substrate,suggesting the necessity of chromosomal remodeler in the deposition of DNA methylation on nucleosomes.

关键词： al. somal chromosomal

Infl uence of altitude and tree class on climate-growth relationships in a larch plantation in subtropical china

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Journal of Forestry Research 2023年第6期34卷 1869-1880页

作者： chunyan Wu Dongsheng chen Xiaomei Sun Shougong zhang State Key Laboratory of Tree Genetics and breeding Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland AdministrationResearch Institute of ForestryChinese Academy of ForestryBeijing 100091People’s Republic of China

Precise quantifi cation of climate-growth relationships can make a major contribution to scientifi c forest ***,whether diff erences in the response of growth to climate at diff erent altitudes remains *** answer this,264 trees of Larix kaempferi from 88 plots,representing diff erent altitudinal ranges(1000-2100 m)and tree classes were sampled and used to develop tree-ring ***-ring growth(TRG)was either positively(dominant)or negatively(intermediate and suppressed)correlated with climate in diff erent tree classes at diff erent *** was strongly correlated with growing season at low altitudes,but was less sensitive to climate at middle *** was mainly limited by precipitation and was highly sensitive to climate at low ***-growth relationships at high altitudes were opposite compared to those at low *** of dominant trees was more sensitive to climate change compared to intermediate and suppressed *** factors(annual temperatures;moisture,the number of frost-free days)had diff erent eff ects on tree-ring growth of diff erent tree classes along altitudinal *** was concluded that the increase in summer temperatures decreased water availability,resulting in a signifi cant decline in growth rates after 2005 at lower *** is suitable for planting in middle altitudes and dominant trees were the best sampling choice for accurately assessing climate-growth relationships.

关键词： Tree-ring width index chronology correlation coeffi cient Additive mixed models Tree classes

Model test and discrete element method simulation of shield tunneling face stability in transparent clay

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Frontiers of Structural and civil Engineering 2021年第1期15卷 147-166页

作者： Huayang LEI Yajie zhang Yao HU Yingnan LIU School of civil Engineering Tianjin UniversityTianjin 300350China Key Laboratory of coast civil Structure Safety(Tianjin University) Ministry of EducationTianjin 300350China Key Laboratory of Earthquake Engineering Simulation and Seismic Resilience of china Earthquake Administration(Tianjin University) Tianjin 300350China

The stability of the shield tunneling face is an extremely important factor affecting the safety of tunnel *** this study,a transparent clay with properties similar to those of Tianjin clay is prepared and a new transparent clay model test apparatus is developed to overcome the“black box”problem in the traditional model *** stability of the shield tunneling face(failure mode,influence range,support force,and surface settlement)is investigated in transparent clay under active failure.A series of transparent clay model tests is performed to investigate the active failure mode,influence range,and support force of the shield tunneling face under different burial depth conditions,whereas particle flow code three-dimensional numerical simulations are conducted to verify the failure mode of the shield tunneling face and surface settlement along the transverse section under different burial depth *** results show that the engineering characteristics of transparent clay are similar to those of soft clay in binhai,Tianjin and satisfy visibility *** types of failure modes are obtained:the overall failure mode(cover/diameter:c/D£1.0)and local failure mode(c/D≥2.0).The influence range of the transverse section is wider than that of the longitudinal section when c/D≥***,the normalized thresholds of the relative displacement and support force ratio are 3%-6%and 0.2-0.4,*** to the cushioning effect of the clay layer,the surface settlement is significantly reduced as the tunnel burial depth increases.

关键词： shield tunneling face stability transparent clay model test numerical simulation

Lanthanide ion-doped upconversion nanoparticles for low-energy super-resolution applications

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Light(Science & Applications) 2024年第11期13卷 2454-2488页

作者： Simone Lamon Haoyi Yu Qiming zhang Min Gu School of Artificial Intelligence Science and Technology University of Shanghai for Science and Technology200093 ShanghaiChina Institute of Photonic chips University of Shanghai for Science and Technology200093 ShanghaiChina

Energy-intensive technologies and high-precision research require energy-efficient techniques and *** optical microscopy technology is useful for low-energy applications in the life sciences and other fields of technology,but standard techniques cannot achieve applications at the nanoscale because of light *** super-resolution techniques have broken beyond the light diffraction limit,enabling 3D applications down to the molecular scale and striving to reduce energy *** targeted super-resolution techniques have achieved high resolution,but the high light intensity needed to outperform competing optical transitions in nanomaterials may result in photo-damage and high energy *** efforts have been made in the development of nanomaterials to improve the resolution and efficiency of these techniques toward low-energy super-resolution *** ion-doped upconversion nanoparticles that exhibit multiple long-lived excited energy states and emit upconversion luminescence have enabled the development of targeted super-resolution techniques that need low-intensity *** use of lanthanide ion-doped upconversion nanoparticles in these techniques for emerging low-energy super-resolution applications will have a significant impact on life sciences and other areas of *** this review,we describe the dynamics of lanthanide ion-doped upconversion nanoparticles for superresolution under low-intensity light and their use in targeted super-resolution *** highlight low-energy super-resolution applications of lanthanide ion-doped upconversion nanoparticles,as well as the related research directions and *** aim is to analyze targeted super-resolution techniques using lanthanide ion-doped upconversion nanoparticles,emphasizing fundamental mechanisms governing transitions in lanthanide ions to surpass the diffraction limit with low-intensity light,and exploring their implications for low-

关键词： materials. lanthanide resolution

Early ERP effects on the scaling of spatial attention in visual search

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Progress in Natural Science:Materials International 2008年第4期18卷 381-386页

作者： Ya-Nan Niu a,b, Jing-Han Wei a, Yue-Jia Luo a,c, a Institute of Psychology, chinese Academy of Sciences, beijing 100101, china b Graduate School of chinese Academy of Sciences, beijing 100049, china c State Key Laboratory of cognitive Neuroscience and Learning, beijing Normal University, 19 Xin-wai Avenue, beijing 100875, china Institute of Psychology Chinese Academy of Sciences Beijing 100101 China Graduate School of chinese Academy of Sciences Beijing 100049 China State Key Laboratory of cognitive Neuroscience and Learning Beijing Normal University 19 Xin-wai Avenue Beijing 100875 China

This article describes the examination of the spatial ’scaling’ effect of visual attention with the technique of event-related potential (ERP). Eighteen participants were involved in a visual search task in which the cue-target paradigm was used. The search array was three concentric circles consisting of randomly selected English letters that were equally distributed in each circle. The behavioral and ERP data were recorded, respectively. The behavioral results showed that the response time increased and the response accuracy decreased with the increase of precue size. The ERPs amplitude of P1 and N1 components evoked by search array increased with the reduction of precue size. However, the latencies of these ERP components did not show significant differences between conditions. The hierarchical data of both behavioral assessment and ERPs provided evidence for the spatial ’scaling’ effect of visual attention. The amplitudes of P1 and N1 components may be used as indices to examine the effect of spatial ’scaling’. In different tasks, the display-set size of stimuli and the task complexity may be important factors that affect the attention allocation.

关键词： Visual search Spatial attention ‘Scaling’ effect Event-related potential

Silver-catalyzed unstrained c(cO)–alkyl bond scission via[3+2]/retro-[3+2]cycloaddition of ketones with N-isocyanoiminotriphenylphosphorane

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Science china chemistry 2021年第7期64卷 1157-1163页

作者： Zikun Wang Linxuan Li Xueying zhang Xihe bi Department of chemistry Northeast Normal UniversityChangchun 130024China State Key Laboratory of Elemento-Organic chemistry Nankai UniversityTianjin 300071China

c(cO)–alkyl bonds are ubiquitous in a variety of organic molecules,and their selective activation and functionalization are important for the reconstruction of simple ketones into valuable building ***,due to the thermodynamic and kinetic stability,the cleavage and transformation of the unstrained c(cO)–alkyl bonds remain a significant ***,we report a novel silver-catalyzed scission of the unstrained c(cO)–alkyl bond of ketones by reacting with N-isocyanoiminotriphenylphosphorane(NIITP)under mild *** method could transform a variety of unstrained ketones into iminophosphoranes and nitriles in high *** and computational studies disclosed the reaction proceeded through an unprecedented[3+2]/retro-[3+2]cycloaddition mechanism.

关键词： silver-catalyzed c-c.b.nd scission unstrained ketones tertiary alcohol intermediates cycloaddition

Anode reaction mechanisms of Na|Nacl-cacl2|Zn liquid metal battery

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Journal of Energy chemistry 2022年第9期31卷 81-87,I0003页

作者： Fang zhang jingyun Jin Junli xu Zhongning Shi School of Metllurgy Northeastem UniversityShenyang110819LiaoningChina colege of Sciences Northeastem UniversityShenyang100819LiaoningChina State Key Laboratory of Roling and Automation Northeastern UniversiyShenyang 110819LiaoningChina

Na|Nacl-cacl_(2)|Zn liquid metal battery is regarded as a promising energy storage system for power *** intensive attempts to present a real mechanism of metal electrodes reaction, those for Na||Zn LMbs are not clear yet. Herein, the anode reactions for the multiple discharge potential plateaus were deduced by means of FactSage thermochemical software, which were subsequently validated by X-ray diffraction analysis and the modeling of phase transformation in the cooling process. A pre-treatment process was proposed for the analysis of anode product composition using the atomic absorption spectrometry method, and the anode states at working temperature(560 ℃) were obtained by the Na-caZn ternary phase for the first time. The results indicate the discharge of Na and ca led to the formation of ca-Zn intermetallic compounds, whilst the extraction of ca in ca-Zn intermetallic compounds was responsible for the multiple discharge plateaus. Moreover, it was found that the charging product was in electrochemical double liquid metal layers, which are composed of Na and ca with dissolved Zn respectively.

关键词： Liquid metal battery Thermodynamic calculation Discharge plateaus Reaction mechanisms ca-Zn intermetallic compounds

Empirical likelihood estimation of discretely sampled processes of OU type

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Science china Mathematics 2009年第5期52卷 908-931页

作者： SUN ShuGuang zhang XinSheng School of Management Fudan UniversityShanghai 200433China

This paper presents an empirical likelihood estimation procedure for parameters of the discretely sampled process of Ornstein-Uhlenbeck type. The proposed procedure is based on the condi- tional characteristic function, and the maximum empirical likelihood estimator is proved to be consistent and asymptotically normal. Moreover, this estimator is shown to be asymptotically efficient under some mild conditions. When the background driving Lévy process is of type A or b, we show that the intensity parameter can be exactly recovered, and we study the maximum empirical likelihood estimator with the plug-in estimated intensity parameter. Testing procedures based on the empirical likelihood ratio statistic are developed for parameters and for estimating equations, respectively. Finally, Monte carlo simulations are conducted to demonstrate the performance of proposed estimators.

关键词： process of OU type conditional characteristic function empirical likelihood instrument variable 62M02 62M05