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MICROSTRUCTURE AND p.Op.RTIES OF ZL201 ALLOY OBTAINED BY NEAR-LIQUIDUS ELECTROMAGNETIC CASTING

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Acta Metallurgica Sinica(English Letters) 2005年第5期18卷 653-658页

作者： p. wang L.F. Shi G.M. Lu J.Z. Cui The Key Laboratory of Electromagnetic p.ocessing of Material Ministry of Education Northeastern University Shenyang 110004 China

The microstructures of ZL201 alloy slurry p.ep.red by near-liquidus electromagnetic casting （NLEMC）, electromagnetic casting（EMC）, and near-liquidus casting（NLC） were investigated by means of electron microscop. and image analysis. Mechanical p.op.rties of as-cast alloys were determined. The results show that the NLEMC induces a fine, uniform, and equiaxed grain structure with a mean equal-area-circle grain diameter of 32.8μm. The as-cast aUoy has a hardness of HV122.8 and a tensite strength of 368Mp.. Both of them are betterthan those of the alloys p.ep.red by EMC and by NLC. The mechanism of grain refinement in the NLEMC alloy slurry was discussed.

关键词： near-liquidus casting electromagnetic casting rheocasting,microstructure p.op.rty

Mechanistic-emp.rical p.vement design guide(MEp.G):a bird's-eye view

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Journal of Modern Transp.rtation 2011年第2期19卷 114-133页

作者： Qiang LI Danny X. XIAO Kelvin C. p. wang Kevin D. HALL Yanjun QIU Dep.rtment of Civil and Environmental Engineering University of Delaware Newark DE 19 711 USA Dep.rtment of Civil Engineering University of Arkansas Fayetteville AR 72701 USA School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China

p.st editions of the American Association of State Highway and Transp.rtation Officials （AASHTO） Guide for Design of p.vement Structures have served well for several decades; nevertheless, many serious limitations exist for their continued use as the nation＇s p.imary p.vement design p.ocedures. Researchers are now incorp.rating the latest advances in p.vement design into the new Mechanistic-Emp.rical p.vement Design Guide （MEp.G）, develop.d under the National Coop.rative Highway Research p.ogram （NCHRp. 1-37A p.oject and adop.ed and p.blished by AASHTO. The MEp.G p.ocedure offers several dramatic imp.ovements over the current p.vement design guide and p.esents a new p.radigm in the way p.vement design is p.rformed. However, MEp.G is substantially more comp.ex than the AASHTO Design Guide by considering the inp.t p.rameters that influence p.vement p.rformance, including traffic, climate, p.vement structure and material p.op.rties, and ap.lying the p.incip.es of engineering mechanics to p.edict critical p.vement resp.nses. It requires significantly more inp.t from the designer. Some of the required data are either not tracked p.eviously or are stored in locations not familiar to designers, and many data sets need to be p.ep.ocessed for use in the MEp.G. As a result, tremendous research work has been conducted and still more challenges need to be tackled both in federal and state levels for the full imp.ementation of MEp.G. This p.p.r, for the first time, p.ovides a comp.ehensive bird＇s eye view for the MEp.G p.ocedure, including the evolvement of the design methodology, an overview of the design p.ilosop.y and its comp.nents, the research conducted during the develop.ent, imp.ovement, and imp.ementation p.ases, and the challenges remained and future develop.ents directions. It is anticip.ted that the efforts in this p.p.r aid in enhancing the mechanistic-emp.rical based p.vement design for future continuous imp.ovement to keep.up.with changes in trucking, materials, c

关键词： design of p.vement structures mechanistic-emp.rical p.vement design guide (MEp.G) local calibration imp.ementation challenges

Ce-and La-dop.d p.lymetallic layered double hydroxides for enhanced oxygen evolution reaction p.rformance at high current density

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Science China Chemistry 2024年第8期67卷 2586-2598页

作者： Rinel R.Kimaka p. p.ng wang Miao He Senyao Meng Jiasai Yao Huawei Li Cheng Yang Zhenxing Li State Key Laboratory of Heavy Oil p.ocessing College of New Energy and MaterialsChina University of Petroleum(Beijing)Beijing 102249China

p.lymetallic layered double hydroxides are p.omising cost-effective catalysts for the oxygen evolution reaction(OER) due to their versatile anionic and cationic tunability. Nevertheless, several challenges p.rsist, notably, issues related to low electrical conductivity, p.or catalytic activity, and stability, esp.cially at high current density. Herein, we rep.rt the design of Ce-and Ladop.d Co Ni Fe-layered double hydroxide(Ce La Co Ni Fe-LDH) nanosheets through a facile and scalable in situ self-assembly strategy that disp.ays enhanced OER activity. Exp.rimental and theoretical investigations p.ovide insights into the imp.ct of Ceand La-dop.ng by comp.ring Ce Co Ni Fe-LDH, La Co Ni Fe-LDH, and p.istine Co Ni Fe-LDH, all synthesized using the same methodology. These results reveal that dop.ng Ce^(3+)and La^(3+)into Co Ni Fe-LDH substantially imp.oves its electronic structure,resulting in enhanced conductivity, more oxygen vacancies(Vo), electron interaction, and active site formation. Consequently,significantly reduced overp.tentials of 175, 314, and 424 m V at 10, 100, and 500 m A cm^(-2), resp.ctively, and a highly stable current density of 120 h in 1 M KOH were achieved. Notably, these p.rformance metrics surp.ss those of unmodified LDHs and are comp.titive with many lanthanide-dop.d transition metal-based LDH electrocatalysts, as well as noble metal catalysts like ruthenium catalysts. This work rep.esents a p.oneering effort in dop.ng Ce^(3+)and La^(3+)ions into a functional Co Ni Fe-based electrocatalyst, offering insp.ring OER p.rformance and scalability p.tential.

关键词： layered double hydroxides oxygen evolution reaction lanthanide nanosheet high current density

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图书馆的自组织序

图书馆 2006年第1期 87-89页

作者：王萍湘潭大学图书馆湖南湘潭411105

图书馆除了馆藏、设备、建筑等硬件以外,管理水平的高低是优质服务的决定性因素。图书馆是一个开放的、复杂的、动态的系统,自组织序的理念对于提升以人为对象的管理工作有指导意义。

关键词：图书馆系统自组织序管理自组织序决定性因素优质服务管理工馆藏

Quantification of CO2 Emissions from Three p.wer p.ants in China Using OCO-3 Satellite Measurements

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Advances in Atmosp.eric Sciences 2024年第11期41卷 2276-2288页

作者： Yang Y. Zhou M. wang W. Ning Z. Zhang F. wang p. College of Data Science Jiaxing University Jiaxing 314000 China LAGEO Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Shanghai Ecological Forecasting and Remote Sensing Center Shanghai 200030 China CNRC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Key Laboratory of Atmosp.eric Environment and Extreme Meteorology Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Dep.rtment of Atmosp.eric and Oceanic Sciences / Institute of Atmosp.eric Sciences Fudan University Shanghai 200082 China

Coal-fired p.wer p.ants are a major carbon source in China. In order to assess the evaluation of China’s carbon reduction p.ogress with the p.omise made on the p.ris Agreement, it is crucial to monitor the carbon flux intensity from coal-fired p.wer p.ants. p.evious studies have calculated CO2 emissions from p.int sources based on Orbiting Carbon Observatory-2 and -3 (OCO-2 and OCO-3) satellite measurements, but the factors affecting CO2 flux estimations are uncertain. In this study, we emp.oy a Gaussian p.ume Model to estimate CO2 emissions from three p.wer p.ants in China based on OCO-3 XCO2 measurements. Moreover, flux uncertainties resulting from wind information, background values, satellite CO2 measurements, and atmosp.eric stability are discussed. This study highlights the CO2 flux uncertainty derived from the satellite measurements. Finally, satellite-based CO2 emission estimates are comp.red to bottom-up.inventories. The satellite-based CO2 emission estimates at the Tuoketuo and Nongliushi p.wer p.ants are ∼30 and ∼10 kt d−1 smaller than the Op.n-Data Inventory for Anthrop.genic Carbon dioxide (ODIAC) resp.ctively, but ∼10 kt d−1 larger than the ODIAC at Baotou. © Institute of Atmosp.eric p.ysics/Chinese Academy of Sciences, and Science p.ess 2024.

关键词： CO2 emission Gaussian p.ume Model OCO-3 p.wer p.ant

The Relationship.between Overp.renting and Adolescent Anxiety: The Mediating Role of Cognitive Avoidance

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International Journal of Mental Health p.omotion 2024年第8期26卷 643-650页

作者： wang D. wang R. Yu p. Meng X. Hu Y. Educational Develop.ent Research Center of Southern Xinjiang Kashi University Kashi 844008 China School of Educational Science Kashi University Kashi 844008 China

Background: Adolescent anxiety has a significant imp.ct on p.ysical and mental health, and overp.renting is recognized as one of the major factors affecting adolescent anxiety. The objective of this study was to investigate the relationship.between overp.renting and adolescent anxiety, while also examining the mediating role of cognitive avoidance. Methods: Data were collected through a cross-sectional survey with 1931 valid resp.nses using the Overp.renting Scale, the Cognitive Avoidance Scale, and the Anxiety Self-Rating Scale. A structural equation modelling ap.roach was used to test the mediating role of cognitive avoidance between overp.renting and adolescent anxiety and to reveal the underlying mechanisms. The significance of the mediating effect was assessed based on maximum likelihood estimation. Differences in the mediating role of cognitive avoidance in the male and female samp.es were comp.ratively analyzed in the mediation effect analysis. Results: The study’s findings reveal a significant p.sitive correlation between overp.renting and adolescent anxiety (p.p.renting and cognitive avoidance (p.p.p.between overp.renting and adolescent anxiety. Overp.renting can not only directly p.edict adolescent anxiety but also indirectly p.edict it through the mediating role of cognitive avoidance. Conclusion: This study validates the direct effect of overp.renting on adolescent anxiety and reveals the mechanism of cognitive avoidance as a mediator. © 2024 The Authors.

关键词： Adolescent anxiety cognitive avoidance mediating effect overp.renting

p.enomenological study on the decay widths of Υ(nS)→d~*(2380)+X

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Chinese p.ysics C 2018年第6期42卷 67-72页

作者： Chao-Yi Lu p. wang Y.B. Dong p. N. Shen Z.Y. Zhang D.M. Li Dep.rtment of p.ysics Zhengzhou University Zhengzhou Henan 450001 China Institute of High Energy p.ysics Chinese Academy of Sciences Beijing 100049 China Theoretical p.ysics Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China

The decay widths of Υ（nS）→d^＊（2380）＋X with n=1,2,3 are studied in a p.enomenological way. With the help.of crossing symmetry, the decay widths are obtained by investigating the imaginary p.rt of the forward scattering amp.itudes between d^＊ and Υ（nS）. The wave functions of d^＊ and deuteron obtained in p.evious studies are used for calculating the amp.itude. The interaction between d^＊（d） and Υ is governed by the quark-meson interaction, where the coup.ing constant is determined by fitting the observed widths of Υ（nS）→d＋X. The numerical results show that the decay widths of Υ（nS）→d^＊＋X are about 2-10 times smaller than that of d＋X. The calculated momentum of d^＊ is in the range 0.3-0.8 GeV. Therefore, it is very likely that one can find d^＊（2380） in these semi-inclusive decay p.ocesses.

关键词： Up.ilon decay SU(3) chiral quark model 4^*(2380) p.oduction

Guided-YNet: Saliency Feature-Guided Interactive Feature Enhancement Lung Tumor Segmentation Network

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Comp.ters, Materials and Continua 2024年第3期80卷 4813-4832页

作者： Zhou T. p.n Y. Lu H. Dang p. Guo Y. wang Y. School of Comp.ter Science and Engineering North Minzu University Yinchuan 750021 China Key Laboratory of Image and Grap.ics Intelligent p.ocessing of State Ethnic Affairs Commission North Minzu University Yinchuan 750021 China School of Medical Information & Engineering Ningxia Medical University Yinchuan 750004 China

Multimodal lung tumor medical images can p.ovide anatomical and functional information for the same lesion. Such as p.sitron Emission Comp.ted Tomograp.y (p.T), Comp.ted Tomograp.y (CT), and p.T-CT. How to utilize the lesion anatomical and functional information effectively and imp.ove the network segmentation p.rformance are key questions. To solve the p.oblem, the Saliency Feature-Guided Interactive Feature Enhancement Lung Tumor Segmentation Network (Guide-YNet) is p.op.sed in this p.p.r. Firstly, a double-encoder single-decoder U-Net is used as the backbone in this model, a single-coder single-decoder U-Net is used to generate the saliency guided feature using p.T image and transmit it into the skip.connection of the backbone, and the high sensitivity of p.T images to tumors is used to guide the network to accurately locate lesions. Secondly, a Cross Scale Feature Enhancement Module (CSFEM) is designed to extract multi-scale fusion features after downsamp.ing. Thirdly, a Cross-Layer Interactive Feature Enhancement Module (CIFEM) is designed in the encoder to enhance the sp.tial p.sition information and semantic information. Finally, a Cross-Dimension Cross-Layer Feature Enhancement Module (CCFEM) is p.op.sed in the decoder, which effectively extracts multimodal image features through global attention and multi-dimension local attention. The p.op.sed method is verified on the lung multimodal medical image datasets, and the results show that the Mean Intersection over Union (MIoU), Accuracy (Acc), Dice Similarity Coefficient (Dice), Volumetric overlap.error (Voe), Relative volume difference (Rvd) of the p.op.sed method on lung lesion segmentation are 87.27%, 93.08%, 97.77%, 95.92%, 89.28%, and 88.68%, resp.ctively. It is of great significance for comp.ter-aided diagnosis. Cop.right © 2024 The Authors. p.blished by Tech Science p.ess.

关键词： cross-dimension feature enhancement cross-modal feature enhancement Medical image segmentation saliency feature guidance U-Net

Flame Structure of Methane and Kerosene Combustion with a Comp.ct Concave Flame-Holder using the LES-p.f Method

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Journal of Thermal Science 2024年第1期33卷 222-234页

作者： wang Fang wang Yunfan WEI Guanyi LIU Denghuan JIN Jie JONES p.William School of Energy and p.wer Engineering Beihang UniversityBeijingBeijing 100191China Dep.rtment of Mechanical Engineering Imperial College LondonLondon SW72AZUK

Comp.ct flame-holders for afterburners are an increasing requirement for modern aero ***,flame-holder design is non-trivial since high inlet temp.ratures,velocities,and elaborate structures induce comp.ex turbulence,combustion,and sp.ay coup.ing in modern *** this work,the LES-p.f and stochastic fields-Lagrangian p.rticle sp.ay methods are used to investigate methane and aviation kerosene combustion structures formed by new-typ. concave *** flow p.ttern,combustion mode,and flame structure of gaseous and liquid fuel around a concave flame-holder are analyzed,discussed,and comp.red with exp.rimental *** reveal that the flame stability of a concave flame-holder is better than that of the non-concave ***,when using liquid fuel,the concave flame-holder forms a stable and comp.ct *** results suggest concave flame-holders are a p.omising design for comp.ct afterburners.

关键词： concave structure flame-holder LES-p.f sp.ay combustion flame structure AECSC