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Estimation of j—R Curves for Small-Sized COEC Specimens and Its Application Considering Crack-Tip Cons tr aints

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Acta Mechanica Solida Sinica 2019年第3期32卷 261-276页

作者： G.W.He C.bao L.x.Cai Y.j.Wu Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China

The normalization method has been employed to estimate the j-resistance (j—R) curves for C-shaped outside edge-notched compression (COEC) specimens of SA-508 steel. The COEC specimens present the lowest j—R curves in comparison with other three types of specimens. Based on the j—Q—M met hod, the constraint parame ter Q determined at the mid-plane in the through-thickness direction of the specimen is used to approximately quantify the threedimensional crack-tip constraint for COEC specimens. Combining with the previous experiments on j—R curves, the constraint-coirected j—R curves for SA-508 steel specimens are given, which may be used to predict the fracture toughness of actual cracked components in structural integrity assessment.

关键词： Ductile fracture toughness COEC specimen Dimensionless load separation principle Normalization method Crack-tip constraint j-Q-M method

跨越新生适应障碍:中国大学入学教育的运行机制及其成效

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华东师范大学学报（教育科学版） 2025年第1期43卷 49-66页

作者：鲍威何元皓何峰厦门大学高等教育发展中心厦门361005 厦门大学教育研究院厦门361005 北京大学教育经济研究所北京100871 北京大学未来教育管理研究中心北京100871 北京大学研究生院北京100871

入学教育是帮助新生适应大学环境、形成自我与社会认知、充分融入大学生活的重要桥梁。鉴于我国大学新生普遍存在学术性、社会性双重适应障碍,在通过国际比较清晰认识中国入学教育运行机制特征的基础上,利用全国大一学生调查数据,科学... 详细信息

入学教育是帮助新生适应大学环境、形成自我与社会认知、充分融入大学生活的重要桥梁。鉴于我国大学新生普遍存在学术性、社会性双重适应障碍,在通过国际比较清晰认识中国入学教育运行机制特征的基础上,利用全国大一学生调查数据,科学评估入学教育在缓减新生适应障碍中的干预成效。研究表明,采用长期深度教育形式,传递专业学科认知、学习方法习得、心理健康建设3大教育内容向度的入学教育运行机制,对缓减学生学术性、社会性双重适应障碍具有积极效用。囿于精准化帮扶举措欠缺,入学教育对弱势学生的补偿效应有待加强。结论为完善大学入学教育、保障人才培养质量提供科学启示。

关键词：入学教育大学新生学术性适应社会性适应

Distributed Control of Chemical Process Networks

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International journal of Automation and computing 2015年第4期12卷 368-381页

作者： Michael j.Tippett jie bao School of Chemical Engineering The University of New South Wales

In this paper,we present a review of the current literature on distributed(or partially decentralized) control of chemical process *** particular,we focus on recent developments in distributed model predictive control,in the context of the specific challenges faced in the control of chemical process *** paper is concluded with some open problems and some possible future research directions in the area.

关键词： Distributed process control chemical process systems process networks plantwide control distributed model predictive control.

Designing hetero-structured ultra-strong and ductile Zr-2.5Nb alloys:Utilizing the grain size-dependent martensite transformation during quenching

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journal of Materials Science & Technology 2022年第30期125卷 198-211页

作者： S.Y.Liu j.Y.Zhang j.Kuang x.Y.bao D.D.Zhang C.L.Zhang j.K.Yang G.Liu j.Sun State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China

To further improve the service performance of Zr-2.5Nb alloy worked as pressure tubes in pressurized heavy water reactors,more investigation about the microstructure and thermomechanical processing route of Zr-2.5Nb alloy need to be *** this work,a hetero-structured Zr-2.5Nb alloy was prepared by applying a novel *** analysis reveals that the alloy exhibits a grain sizedependent martensite substructure transition during post-rolling *** hetero-structure consists of equiaxed primaryαgrains and the lamellae groups containing both parallelα’dislocation martensite andα’twin *** with the previously reported Zr-Nb alloys,the present Zr-2.5Nb alloys manifest the highest yield strength(∼710 MPa),together with a high ultimate tensile strength(∼844 MPa)and good ductility(∼17.1%).The enhanced mechanical properties are found to arise from the properly controlled fraction/size of the two types of martensite,which not only significantly strengthens the alloy but also contributes to a stronger strain hardening.A model based on the grain-size-dependent critical resolved shear stress for dislocation slip and twinning has been proposed to explain theα’martensite substructures transition at a critical grain size dc=3.3μ*** this size,the critical resolved shear stress(CRSS)for twinning is higher than that for the***,theα’dislocation martensite is more favorable to ***,theα’twin martensite would exhibit a high *** present work indicates that making use of the grain size-dependent martensite transformation to tailor the heterostructure in Zr alloys is an effective strategy to overcome the strength–ductility trade-off in the material.

关键词： Zr-Nb alloys Heterogeneous structure Martensitic transformation Grain size Strength

Recent weakening of seasonal temperature difference in East Asia beyond the historical range of variability since the 14th century

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Science China Earth Sciences 2023年第5期66卷 1133-1146页

作者： jianglin WANG bao YANG Zhiyuan WANG jürg LUTERBACHER Fredrik Charpentier LjUNGQVIST Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China School of Geography and Ocean Science Nanjing UniversityNanjing210023China College of Geography and Environmental Science Zhejiang Normal UniversityJinhua321004China Science and Innovation Department World Meteorological Organization(WMO)Geneva1211Switzerland Department of History Stockholm UniversityStockholm10691Sweden Bolin Centre for Climate Research Stockholm UniversityStockholm10691Sweden Swedish Collegium for Advanced Study LinneanumThunbergsvägen 2Uppsala75238Sweden

Seasonal differences of temperature are crucial components of the Earth's climate ***,the relatively short observational record,especially for East Asia,has limited progress in understanding seasonal *** this study,we identify ten tree-ring chronologies separately correlated with local winter(December-February)temperatures and twelve different tree-ring chronologies separately correlated with summer(june-August)temperatures across East *** these discrete seasonal tree-ring chronologies,we develop two independent winter and summer temperature reconstructions covering the period 1376-1995 CE for East Asia,and compare them with model *** reconstructions show a more significant volcanic cooling and earlier onset of modern warming in summer than in *** reconstructed summer-minus-winter temperature decreased since as early as the late 19th century,which has driven the current state of seasonal temperature difference to out of the natural variability since the *** models could generally reproduce the variability and trends in seasonal reconstructions,but might largely underestimate seasonal differences due to the fact that seasonal expressions on external forcing and modes of internal variability are too *** study highlights the importance of using proxy-based seasonal reconstructions to evaluate the performance of climate models,and implies a substantial weakening of seasonal temperature differences in the future.

关键词： Seasonal temperature differences Temperature reconstruction East Asia Tree rings Recent warming

A polarizing situation： Taking an in-plane perspective for next-generation near-field studies

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Frontiers of physics 2016年第2期11卷 1-17页

作者： P. james Schuck Wel bao Nicholas j. Borys Molecular Foundry Lawrence Berkeley National Laboratory Berkeley CA 94720 USA Department of Materials Science and Engineering University of California Berkeley CA 94720-1760 USA

By enabling the probing of light-matter interactions at the functionally relevant length scales of most materials, near-field optical imaging and spectroscopy accesses information that is unobtainable with other methods. The advent of apertureless techniques, which exploit the ultralocalized and enhanced near-fields created by sharp metallic tips or plasmonic nanoparticles, has resulted in rapid adoption of near-field approaches for studying novel materials and phenomena, with spatial resolution approaching sub-molecular levels. However, these approaches are generally limited by the dominant out-of-plane polarization response of apertureless tips, restricting the exploration and discovery of many material properties. This has led to recent design and fabrication breakthroughs in near-field tips engineered specifically for enhancing in-plane interactions with near-field light components. This mini-review provides a perspective on recent progress and emerging directions aimed at utilizing and controlling in-plane optical polarization, highlighting key application spaces where in-plane near-field tip responses have enabled recent advancements in the understanding and development of new nanostructured materials and devices.

关键词： near-field optical microscopy nano-optics TERS plasmonics optical antenna 2D materials

The arms race between Magnaporthe oryzae and rice: Diversity and interaction of Avr and R genes

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journal of Integrative Agriculture 2017年第12期16卷 2746-2760页

作者： WANG bao-hua Daniel j.Ebbole WANG Zong-hua College of Plant Protection/Fujian University Key Laboratory for Plant-Microbe Interaction Fujian Agriculture and Forestry University Department of Plant Pathology and Microbiology Texas A&M UniversityCollege Station Ocean Institute Minjiang University

Rice blast disease, caused by Magnaporthe oryzae, threatens global food security. The rice blast pathosystem is a longstanding model system for understanding plant-microbe interactions. In order to elucidate the coevolution of the host and pathogen, and provide the appropriate methods for preventing or controlling rice blast disease, researchers have focused on the evolution of virulence factors and resistance genes. Thus far, more than 30 rice blast resistance（R） genes and 12 avirulence（Avr） genes have been cloned. This review summarizes the cloned rice blast R genes, cloned Avr genes of M. oryzae and the interaction between them. This discussion also considers some of the major unanswered questions concerning this pathosystem and the opportunities for future investigations.

关键词： rice Maganporthe oryzae resistance gene avirulence gene co-evolution genetic diversity

Novel 2-aryl-3,4,5-trihydroxypiperidines:Synthesis and glycosidase inhibition

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Chinese Chemical Letters 2013年第12期24卷 1059-1063页

作者： Hui Zhao Wu-bao Wang Shinpei Nakagawa Yue-Mei jia xiang-Guo Hu George W.j.Fleet Francis x.Wilson Robert j.Nash Atsushi Kato Chu-Yi Yu Beijing National Laboratory for Molecular Science (BNLMS) CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of Sciences Department of Hospital Pharmacy University of Toyama2630 SugitaniToyama 930-0194Japan Chemistry Research Laboratory Department of ChemistryUniversity of Oxford Summit PLC 91Milton ParkAbingdonOxon OX14 4RYUK Phytoquest Limited IBERSPlas GogerddanCeredigionAberystwyth SY23 3EBWalesUK

Three pairs of novel 2-aryl-3,4,5-trihydroxypiperidines （6-8 and their enantiomers）, the piperidine analogues of the pyrrolidine alkaloids radicamine A and radicamine B, were prepared from six- membered cyclic nitrones through a concise two-step procedure, i.e., Grignard reagent addition and deprotection. These novel polyhydroxylated piperidine iminosugars were assayed against 10 types of enzymes. Only compound 8 exhibited weak inhibition （IC50 1080 μmol/L） against β-galactosidase from rat intestinal lactases.

关键词： 2-Aryl polyhydroxylated piperidine lminosugars Radicamine mimics Glycosidase inhibitors

Residual stress determination in friction stir butt welded joints using a digital image correlation-aided slitting technique

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Chinese journal of Aeronautics 2017年第3期30卷 1258-1269页

作者： Yaowu xU Rui bao Institute of Solid Mechanics School of Aeronautic Science and Engineering Beihang University Beijing 100083 China

This paper presents an incremental cutting method for evaluating the longitudinal residual stresses in a butt welded thin plate via combining the traditional residual stress measurement methods and the advanced optical *** proposed approach,which can be called digital image correlation（DIC）-aided slitting technique,introduces a successive extension slot to a specimen and employs the DIC technique to measure the released displacement profiles of the cutting sections after each cutting *** the displacement profiles are used to directly calculate the residual stress distributions up to the slot tip and hence,a stress distribution can be obtained after a cutting ***,all of the stress distributions are averaged to ultimately determine the original residual stress *** method does not include any complex experimental operations or tedious derivation,and the resolution of stress variation is greatly improved by the continuous measurement of the released *** presented method has been preliminarily verified by a specimen with residual stress introduced by a four-point bending *** results show that residual stresses determined by the DIC-aided slitting technique agree well with those from finite element（FE） *** residual stress in a friction stir welded aluminum specimen obtained by the presented technique is also consistent with the evaluations given by x-ray ***,the residual stresses obtained by the DIC-aided slitting technique demonstrate higher accuracy and stability than the evaluations derived by the DIC-aided contour method.

关键词： Contour method Digital image correlation(DIC) Friction stir welding Residual stresses Thin-walled structures