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Phase Selection in Solidi?cation of Undercooled Co–B Alloys

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journal of Materials Science & Technology 2017年第4期33卷 352-358页

作者： X.X.Wei W.Xu j.L.kang M.ferry j.f.Li State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240.China Australian Research Council Centre of Excellence for Design in Light Metals School of Materials Science and EngineeringThe University of New South WalesSydneyNSW 2052Australia

A series Co-（18.5–20.7） at.% B melts encompassing the eutectic composition（Co81.5B18.5） were solidified at different degrees of undercooling. It is found that the metastable Co23B6 phase solidifies as a substitute for the stable Co3 B phase in the alloy melts undercooled above a critical undercooling value of -60 *** Co23B6 and α-Co phases make up a metastable eutectic. The corresponding eutectic composition and temperature are Co80.4B19.6 and 1343 K, respectively. On exposure of the metastable Co23B6 phase at a given temperature above 1208 K, it does not decompose even after several hours. But it transforms by a eutectoid reaction to α-Co ＋ Co3 B at lower temperature.

关键词： Undercooling Rapid solidi?cation Metastable phase diagram Structure evolution

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A REDUCED ORDER SCHWARZ METHOD fOR NONLINEAR MULTISCALE ELLIPTIC EQUATIONS BASED ON TWO-LAYER NEURAL NETWORKS

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journal of Computational Mathematics 2024年第2期42卷 570-596页

作者： Shi Chen Zhiyan Ding Qin Li Stephen j.Wright Mathematics Department University of Wisconsin-MadisonMadisonWI 53706USA Department of Mathematics University of California-BerkeleyBerkeley CA 94720USA Mathematics Department and Discovery Institute University of Wisconsin-Madison MadisonWI 53706USA Computer Sciences Department University of WisconsinMadisonWI 53706USA

Neural networks are powerful tools for approximating high dimensional data that have been used in many contexts,including solution of partial differential equations(PDEs).We describe a solver for multiscale fully nonlinear elliptic equations that makes use of domain decomposition,an accelerated Schwarz framework,and two-layer neural networks to approximate the boundary-to-boundarymap for the subdomains,which is the key step in the Schwarz ***,the boundary-to-boundary map requires solution of boundary-value elliptic problems on each *** leveraging the compressibility of multiscale problems,our approach trains the neural network offline to serve as a surrogate for the usual implementation of the boundary-to-boundary *** method is applied to a multiscale semilinear elliptic equation and a multiscale p-Laplace *** both cases we demonstrate significant improvement in efficiency as well as good accuracy and generalization performance.

关键词： Nonlinear homogenization Multiscale elliptic problem Neural networks Do-main decomposition

Characterization of bright betatron radiation generated by direct laser acceleration of electrons in plasma of near critical density

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Matter and Radiation at Extremes 2024年第2期9卷 26-35页

作者： j.Cikhardt M.Gyrdymov S.Zähter P.Tavana M.M.Günther N.Bukharskii N.Borisenko j.jacoby X.f.Shen A.Pukhov N.E.Andreev O.N.Rosmej faculty of Electrical Engineering Czech Technical University in Prague16627 Prague 6Czech Republic Goethe University FrankfurtMax-von-Laue-Straße 160438 Frankfurt am MainGermany GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany focused Energy GmbH Im Tiefen See 4564293 DarmstadtGermany National Research Nuclear University MEPhI Kashirskoe shosse 31115409 MoscowRussian Federation Lebedev Physical Institute RAS Leninskiy Prospekt 53119991 MoscowRussian Federation Heinrich-Heine-University Düsseldorf Universitätsstrasse 1DüsseldorfGermany joint Institute for High Temperatures RASIzhorskaya st.13Bldg.2125412 MoscowRussian Federation Moscow Institute of Physics and Technology Institutskiy Pereulok 9141700 DolgoprudnyRussia

Directed x-rays produced in the interaction of sub-picosecond laser pulses of moderate relativistic intensity with plasma of near-critical density are investigated. Synchrotron-like (betatron) radiation occurs in the process of direct laser acceleration (DLA) of electrons in a relativisticlaser channel when the electrons undergo transverse betatron oscillations in self-generated quasi-static electric and magnetic fields. In anexperiment at the PHELIX laser system, high-current directed beams of DLA electrons with a mean energy ten times higher than the ponderomotive potential and maximum energy up to 100 MeV were measured at 10^(19) W/cm^(2)laser intensity. The spectrum of directed x-raysin the range of 5–60 keV was evaluated using two sets of Ross filters placed at 0°and 10°to the laser pulse propagation axis. The differential x-ray absorption method allowed for absolute measurements of the angular-dependent photon fluence. We report 10^(13) photons/sr withenergies >5 keV measured at 0°to the laser axis and a brilliance of 10^(21) photons s^(−1) mm^(−2) mrad−2(0.1%BW)−1. The angular distributionof the emission has an fWHM of 14°–16°. Thanks to the ultra-high photon fluence, point-like radiation source, and ultra-short emissiontime, DLA-based keV backlighters are promising for various applications in high-energy-density research with kilojoule petawatt-class laserfacilities.

关键词： laser acceleration critical

Lighting up aggregate emission of perylene diimide by leveraging polymerization-mediated through-space charge transfer and π-π stacking

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Science China Chemistry 2024年

作者： Suiying Ye Désirée füglistaller Tian Tian Anjay Manian Sudhir Kumar Celine Nardo Andrew j.Christofferson Salvy P.Russo Chih-jen Shih jean-Christophe Leroux Yinyin Bao Institute of Pharmaceutical Sciences Department of Chemistry and Applied Biosciences ETH Zurich Vladimir-Prelog-Weg 3 Institute for Chemical and Bioengineering Department of Chemistry and Applied Biosciences ETH Zurich Vladimir-Prelog-Weg 1-5 ARC Centre of Excellence in Exciton Science School of Science RMIT University School of Science STEM College RMIT University

The molecular engineering of fluorescent organic/polymeric materials, specifically those emitting in the deep red to near-infrared spectrum, is vital for advancements in optoelectronics and biomedicine. Perylene diimide(PDI), a well-known fluorescent scaffold, offers high thermal and photophysical stability but suffers from fluorescence quenching in solid or aggregate states due to intense π-π interactions. To mitigate this, simple and versatile methods for strong PDI aggregate emission without extensive synthetic demands are highly desirable but still lacking. Here, we report a straightforward strategy to enhance the solid-state emission of PDI by introducing certain degree of through-space charge transfer(TSCT) via controlled radical polymerization,which can efficiently distort the typical face-to-face PDI stacking, enabling greatly enhanced deep red emission. This is achieved by growing electron-donating star-shape styrenic(co)polymers from a multidirectional electron-accepting PDI initiator. The incorporation of polycyclic aromatic monomers further shifted the emission into the near-infrared region, albeit with a reduced intensity. Overall, the emission of the PDI-based TSCT polymers can be systematically manipulated by leveraging the balance between PDI stacking and the TSCT degree, as confirmed by both experimental study and theoretical calculations. Our approach circumvents complex synthetic procedures, offering highly emissive materials with large Stokes shifts and showing broad potential for optoelectronic technology.

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SARS-CoV-2 variants are associated with different clinical courses in children with MIS-C

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World journal of Pediatrics 2024年第2期20卷 143-152页

作者： Andres f.Moreno Rojas Emelia Bainto Helen Harvey Adriana H.Tremoulet jane C.Burns Kirsten B.Dummer Department of Pediatrics Division of Pediatric CardiologyUniversity of California San Diegoand Rady Children’s Hospital3020 Children’s Way MC 5004San DiegoCA 92123USA Kawasaki Disease Research Center La JollaCAUSA Department of Pediatrics Division of Pediatric Critical CareUniversity of California San Diegoand Rady Children’s HospitalSan DiegoCAUSA Department of Pediatrics University of California San Diegoand Rady Children’s HospitalSan DiegoCAUSA

Background Recent infection with SARS‑CoV-2 in children has been associated with multisystem inflammatory syndrome in children(MIS-C).SARS‑CoV-2 has undergone different *** publications exist about specific variants and their correlation with the severity of *** This was a single-center,retrospective study including all patients admitted with MIS-C at Rady Children’s Hospital-San Diego between May 2020 and March *** epidemiologic data,including viral genomic information,were obtained from public ***,clinical presentation,laboratory values,and outcomes were obtained from electronic medical *** The analysis included 104 pediatric *** MIS-C waves were *** variants in San Diego during the first wave included clades 20A to *** the second wave,there were variants from clades 20A to C,20G,21C(Epsilon),20I(Alpha),and 20j(Gamma).The third wave had Delta strains(clades 21A,21I,and 21j),and the fourth had Omicron variants(clades 21K,21L,and 22C).MIS-C presented with similar symptoms and laboratory findings across all *** patients were admitted to the pediatric intensive care unit(PICU)(74%)and required inotropic support(63%)during the second *** of the patients required mechanical circulatory support,and only two required invasive ventilatory *** was no *** The various strains of SARS-CoV-2 triggered MIS-C with differing severities,with the second wave having a more severe clinical *** the differences in disease severity across variants were due to changes in the virus or other factors remains unknown.

关键词： Complications COVID-19 MIS-C SARS-CoV-2 variants

The effects of local variations in conditions on carbon storage and release in the continental mantle

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National Science Review 2024年第06期 22-36页

作者： Stephen f.foley Chunfei Chen Dorrit E.jacob School of Natural Sciences Macquarie University Research School of Earth Sciences Australian National University State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences

Recent advances indicate that the amount of carbon released by gradual degassing from the mantle needs to be revised upwards, whereas the carbon supplied by plumes may have been overestimated in the *** in rock types and oxidation state may be very local and exert strong influences on carbon storage and release mechanisms. Deep subduction may be prevented by diapirism in thick sedimentary packages,whereas carbonates in thinner sequences may be subducted. Carbonates stored in the mantle transition zone will melt when they heat up, recognized by coupled stable isotope systems(e.g. Mg, Zn, Ca). There is no single ‘mantle oxygen fugacity’, particularly in the thermal boundary layer(TBL) and lowermost lithosphere, where very local mixtures of rock types coexist. Carbonate-rich melts from either subduction or melting of the uppermost asthenosphere trap carbon by redox freezing or as carbonate-rich dykes in this zone. Deeply derived, reduced melts may form further diamond reservoirs, recognized as polycrystalline diamonds associated with websteritic silicate minerals. Carbon is released by either edge-driven convection,which tears sections of the TBL and lower lithosphere down so that they melt by a mixture of heating and oxidation, or by lateral advection of solids beneath rifts. Both mechanisms operate at steps in lithosphere thickness and result in carbonate-rich melts, explaining the spatial association of craton edges and carbonate-rich magmatism. High-pressure experiments on individual rock types, and increasingly on reactions between rocks and melts, are fine-tuning our understanding of processes and turning up unexpected results that are not seen in studies of single rocks. future research should concentrate on elucidating local variations and integrating these with the interpretation of geophysical signals. Global concepts such as average sediment compositions and a uniform mantle oxidation state are not appropriate for small-scale processes; an increa

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Amplitude analysis of the decays D^(0)→π^(+)π^(−)π^(+)π^(−)and D^(0)→π^(+)π^(−)π^(0)π^(0)

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Chinese Physics C 2024年第8期48卷 6-33页

作者： M.Ablikim M.N.Achasov P.Adlarson O.Afedulidis X.C.Ai R.Aliberti A.Amoroso Q.An Y.Bai O.Bakina I.Balossino Y.Ban H.-R.Bao V.Batozskaya K.Begzsuren N.Berger M.Berlowski M.Bertani D.Bettoni f.Bianchi E.Bianco A.Bortone I.Boyko R.A.Briere A.Brueggemann H.Cai X.Cai A.Calcaterra G.f.Cao N.Cao S.A.Cetin j.f.Chang W.L.Chang G.R.Che G.Chelkov C.Chen C.H.Chen Chao Chen G.Chen H.S.Chen M.L.Chen S.j.Chen S.L.Chen S.M.Chen T.Chen X.R.Chen X.T.Chen Y.B.Chen Y.Q.Chen Z.j.Chen Z.Y.Chen S.K.Choi X.Chu G.Cibinetto f.Cossio j.j.Cui H.L.Dai j.P.Dai A.Dbeyssi R.E.de Boer D.Dedovich C.Q.Deng Z.Y.Deng A.Denig I.Denysenko M.Destefanis f.De Mori B.fang S.S.fang W.X.fang Y.fang Y.Q.fang R.farinelli L.fava f.feldbauer G.felici C.Q.feng j.H.feng Y.T.feng K.fischer M.fritsch C.D.fu j.L.fu Y.W.fu H.Gao Y.N.Gao Yang Gao S.Garbolino I.Garzia P.T.Ge Z.W.Ge C.Geng E.M.Gersabeck B.Ding X.X.Ding Y.Ding Y.Ding j.Dong L.Y.Dong M.Y.Dong X.Dong M.C.Du S.X.Du Z.H.Duan P.Egorov Y.H.fan j.fang jA.Gilman K.Goetzen L.Gong W.X.Gong W.Gradl S.Gramigna M.Greco M.H.Gu Y.T.Gu C.Y.Guan Z.L.Guan A.Q.Guo L.B.Guo M.j.Guo R.P.Guo Y.P.Guo A.Guskov j.Gutierrez K.L.Han T.T.Han X.Q.Hao f.A.Harris K.K.He K.L.He f.H.Heinsius C.H.Heinz Y.K.Heng C.Herold T.Holtmann P.C.Hong G.Y.Hou X.T.Hou Y.R.Hou Z.L.Hou B.Y.Hu H.M.Hu j.f.Hu T.Hu Y.Hu G.S.Huang K.X.Huang L.Q.Huang X.T.Huang Y.P.Huang T.Hussain f.H\"olzken N.H\"usken N.in der Wiesche M.Irshad j.jackson S.janchiv j.H.jeong Q.ji Q.P.ji W.ji X.B.ji X.L.ji Y.Y.ji X.Q.jia Z.K.jia D.jiang H.B.jiang P.C.jiang S.S.jiang T.j.jiang X.S.jiang Y.jiang j.B.jiao j.K.jiao Z.jiao S.jin Y.jin M.Q.jing X.M.jing T.johansson S.Kabana N.Kalantar-Nayestanaki X.L.kang X.S.kang M.Kavatsyuk B.C.Ke V.Khachatryan A.Khoukaz R.Kiuchi O.B.Kolcu B.Kopf M.Kuessner X.Kui A.Kupsc W.K\"uhn j.j.Lane P.Larin L.Lavezzi T.T.Lei Z.H.Lei H.Leithoff M.Lellmann T.Lenz C.Li C.Li C.H.Li Cheng Li D.M.Li f.Li G.Li H.Li H.B.Li H.j.Li H.N.Li Hui Li j.R.Li j.S.Li K.Li L.j.Li L.K.Li Lei Li M.H.Li P.R.Li Q.M.Li Q.X.Li R.Li S.X.Li T.Li W.D.Li W.G.Li X.Li X.H.Li X.L.Li X.Y.Li Y Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Beihang University Beijing 100191China Bochum Ruhr-University D-44780 BochumGermany Budker Institute of Nuclear Physics SB RAS(BINP) Novosibirsk 630090Russia Carnegie Mellon University PittsburghPennsylvania 15213USA Central China Normal University Wuhan 430079China Central South University Changsha 410083China China Center of Advanced Science and Technology Beijing 100190China China University of Geosciences Wuhan 430074China Chung-Ang University Seoul06974Republic of Korea COMSATS University Islamabad Lahore CampusDefence RoadOff Raiwind Road54000 LahorePakistan fudan University Shanghai 200433China GSI Helmholtzcentre for Heavy Ion Research GmbH D-64291 DarmstadtGermany Guangxi Normal University Guilin 541004China Guangxi University Nanning 530004China Hangzhou Normal University Hangzhou 310036China Hebei University Baoding 071002China Helmholtz Institute Mainz Staudinger Weg 18D-55099 MainzGermany Henan Normal University Xinxiang 453007China Henan University Kaifeng 475004China Henan University of Science and Technology Luoyang 471003China Henan University of Technology Zhengzhou 450001China Huangshan College Huangshan 245000China Hunan Normal University Changsha 410081China Hunan University Changsha 410082China Indian Institute of Technology Madras Chennai 600036India Indiana University BloomingtonIndiana 47405USA INfN Laboratori Nazionali di frascati INFN Laboratori Nazionali di FrascatiI-00044FrascatiItaly INfN Laboratori Nazionali di frascati INFN Sezione di PerugiaI-06100PerugiaItaly INfN Laboratori Nazionali di frascati University of PerugiaI-06100PerugiaItaly INfN Sezione di ferrara INFN Sezione di FerraraI-44122FerraraItaly INfN Sezione di ferrara University of FerraraI-44122FerraraItaly Inner Mongolia University Hohhot 010021China Institute of Modern Physics Lanzhou 730000China Institute of Physics and Technology Peace Avenue 54BUlaanbaatar 13330Mongolia Instituto de A

Using e^(+)e^(−)annihilation data corresponding to an integrated luminosity of 2.93 fb^(−1)taken at the center-of-mass energy√s=3.773 GeV with the BESIII detector,a joint amplitude analysis is performed on the decays D^(0)→π^(+)π^(−)π^(+)π^(−)and D^(0)→π^(+)π^(−)π^(0)π^(0)(non-η).The fit fractions of individual components are obtained,and large interferences among the dominant components of the decays D^(0)→a_(1)(1260)π,D^(0)→π(1300)π,D^(0)→ρ(770)ρ(770),and D^(0)→2(ππ)_(S)are observed in both *** the obtained amplitude model,the CP-even fractions of D^(0)→π^(+)π^(−)π^(+)π^(−)and D^(0)→π^(+)π^(−)π^(0)π^(0)(non-η)are determined to be(75.2±1.1_(stat).±1.5_(syst.))%and(68.9±1.5_(stat).±2.4_(syst.))%,*** branching fractions of D^(0)→π^(+)π^(−)π^(+)π^(−)and D^(0)→π^(+)π^(−)π^(0)π^(0)(non-η)are measured to be(0.688±0.010_(stat.)±0.010_(syst.))%and(0.951±0.025_(stat.)±0.021_(syst.))%,*** amplitude analysis provides an important model for the binning strategy in measuring the strong phase parameters of D^(0)→4πwhen used to determine the CKM angleγ(ϕ_(3))via the B^(−)→DK^(−)decay.

关键词： BESIII D^(0)meson decays amplitude analysis CP-even fraction

Background removal from global auroral images:Data-driven dayglow modeling

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Earth and Planetary Physics 2024年第1期8卷 247-257页

作者： A.Ohma M.Madelaire K.M.Laundal j.P.Reistad S.M.Hatch S.Gasparini S.j.Walker Birkeland Centre for Space Science Department of Physics and TechnologyUniversity of BergenBergenNorway

Global images of auroras obtained by cameras on spacecraft are a key tool for studying the near-Earth ***,the cameras are sensitive not only to auroral emissions produced by precipitating particles,but also to dayglow emissions produced by photoelectrons induced by *** emissions and scattered sunlight can contribute to the background *** fully utilize such images in space science,background contamination must be removed to isolate the auroral *** we outline a data-driven approach to modeling the background intensity in multiple images by formulating linear inverse problems based on B-splines and spherical *** approach is robust,flexible,and iteratively deselects outliers,such as auroral *** final model is smooth across the terminator and accounts for slow temporal variations and large-scale asymmetries in the *** demonstrate the model by using the three far ultraviolet cameras on the Imager for Magnetopause-to-Aurora Global Exploration(IMAGE)*** method can be applied to historical missions and is relevant for upcoming missions,such as the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission.

关键词： aurora dayglow modeling global auroral images far ultraviolet images dayglow removal

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三轴形变核^(131)Ba中的奇异集体激发模式

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物理学报 2024年第11期73卷 89-100页

作者：韦锐周厚兵王思成丁兵强赟华贾晨旭陈红星郭松 C.M.Petrache D.Mengoni A.Astier E.Dupont 吕冰锋 D.Bazzacco A.Boso A.Goasduff f.Recchia D.Testov f.Galtarossa G.jaworski D.R.Napoli S.Riccetto M.Siciliano j.j.Valiente-Dobon C.Andreoiu f.H.Garcia K.Ortner K.Whitmore A.Ataç-Nyberg T.Bäck B.Cederwall E.A.Lawrie I.Kuti D.Sohler T.Marchlewski j.Srebrny A.Tucholski 广西师范大学物理科学与技术学院桂林541004 广西核物理与核技术重点实验室桂林541004 中国科学院近代物理研究所兰州730000 中国科学院大学北京100049 巴黎萨克雷大学 CNRS/IN2P3IJCLab奥赛91405 帕多瓦大学物理和天文学系帕多瓦I-35131 意大利国家核物理研究所帕多瓦分部帕多瓦I-35131 意大利国家核物理研究所莱尼亚罗国家实验室莱尼亚罗(帕多瓦)I-35020 费拉拉大学理学与自然科学院费拉拉西蒙菲莎大学化学系本拿比BC V5A 1S6 皇家理工学院物理系斯德哥摩尔S-10691 国家研究基金会iThemba加速器科学实验室西萨默塞特7123 西开普大学物理与天文系贝尔维尔ZA-7535 HUN-REN原子核研究所德布勒森4001 华沙巴斯德拉大学重离子实验室华沙02-093

利用意大利Legnaro实验室串列静电加速器提供的65 MeV^(13)C束流与122Sn靶的熔合蒸发反应布居了^(131)Ba的高自旋态,并搭建了新的能级纲图.新的能级纲图由15条转动带组成,包括三对手征双重带,其中两对正宇称手征带为赝自旋-手征四重带.... 详细信息

利用意大利Legnaro实验室串列静电加速器提供的65 MeV^(13)C束流与122Sn靶的熔合蒸发反应布居了^(131)Ba的高自旋态,并搭建了新的能级纲图.新的能级纲图由15条转动带组成,包括三对手征双重带,其中两对正宇称手征带为赝自旋-手征四重带.正负宇称手征带通过一系列增强的E1跃迁连接,表明它们之间存在八极关联.在低自旋区域搭建了一条新的转动带,通过一系列γ跃迁向νh1_(1/2)晕带退激.这种能级结构与摇摆带相似,但基于现有的实验证据还难以将它确认为摇摆带,不能排除其他集体激发机制,如γ振动的影响.

关键词：高自旋态手征带赝自旋八极关联摇摆运动

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