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Impact of T_(i)/T_(e )ratio on ion transport based on EAST H-mode plasmas

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Plasma Science and Technology 2024年第4期26卷 68-78页

作者：刘建文臧庆梁云峰陈佳乐邬潇河 Alexander KNIEPS 扈嘉辉金仡飞张斌储宇奇刘海庆吕波段艳敏李妙辉陈颖杰龚先祖 the EAST Team institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China Forschungszentrum Jülich GmbH Institut für Energie-und Klimaforschung-PlasmaphysikPartner of the Trilateral Euregio Cluster(TEC)Jülich 52425Germany

At the EAST tokamak, the ion temperature(T_(i)) is observed to be clamped around 1.25 keV in electron cyclotron resonance(ECR)-heated plasmas, even at core electron temperatures up to 10 keV(depending on the ECR heating power and the plasma density). This clamping results from the lack of direct ion heating and high levels of turbulence-driven transport. Turbulent transport analysis shows that trapped electron mode and electron temperature gradient-driven modes are the most unstable modes in the core of ECR-heated H-mode plasmas. Nevertheless, recently it was found that the T_(i)/T_(e)ratio can increase further with the fraction of the neutral beam injection(NBI) power, which leads to a higher core ion temperature(Ti0). In NBI heating-dominant H-mode plasmas, the ion temperature gradient-driven modes become the most unstable ***, a strong and broad internal transport barrier(ITB) can form at the plasma core in high-power NBI-heated H-mode plasmas when the T_(i)/T_(e)ratio approaches ~1, which results in steep core Teand Tiprofiles, as well as a peaked neprofile. Power balance analysis shows a weaker Teprofile stiffness after the formation of ITBs in the core plasma region, where Ticlamping is broken,and the core Tican increase further above 2 keV, which is 80% higher than the value of Ticlamping in ECR-heated plasmas. This finding proposes a possible solution to the problem of Ticlamping on EAST and demonstrates an advanced operational regime with the formation of a strong and broad ITB for future fusion plasmas dominated by electron heating.

关键词： ion temperature clamping transport neutral beam injection stiffness internal transport barrier

Bolzano's Theorems for Holomorphic Mappings(To Ham Brezis,with friendship and admiration)

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Chinese Annals of Mathematics,Series B 2017年第2期38卷 563-578页

作者： Jean MAWHIN institut de recherche en mathématique et physique universitécatholique de louvain chemin du cyclotron2 1348 Louvain-la-NeuveBelgium

The existence of a zero for a holomorphic functions on a ball or on a rectangle under some sign conditions on the boundary generalizing Bolzano's ones for real functions on an interval is deduced in a very simple way from Cauchy's theorem for holomorphic functions. A more complicated proof, using Cauchy's argument principle, provides uniqueness of the zero, when the sign conditions on the boundary are strict. Applications are given to corresponding Brouwer fixed point theorems for holomorphic functions. Extensions to holomorphic mappings from C^n to C^n are obtained using Brouwer degree.

关键词： Holomorphic function Hadamard-Shih's conditions Poincaré-Miranda's conditions Bolzano's theorem Cauchy's theorem Brouwer fixed point theorem Brouwer degree

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季风与大气环流系统

科学通报 2009年第7期54卷 533-534页

作者： André Berger institut d'Astronomie et de Géophysique G Lemaǐtre Université Catholique de Louvain Chemin du Cyclotron 2 1348 Louvain-la-Neuve Belgium

人类有气象仪器记录的历史太短,不足以捕捉气候系统全部的变率,更难以用来预测未来数十年到数百年的气候变化.重建过去气候变化的历史、理解其机制和过程可以在很大程度上弥补上述不足.在气候系统中,由于季风的演化与变率对人类经济、... 详细信息

人类有气象仪器记录的历史太短,不足以捕捉气候系统全部的变率,更难以用来预测未来数十年到数百年的气候变化.重建过去气候变化的历史、理解其机制和过程可以在很大程度上弥补上述不足.在气候系统中,由于季风的演化与变率对人类经济、文化和生活节奏的许多方面均有重要影响,其研究工作对社会的重要性也日益增加．亚洲季风受欧亚大陆和印度洋．太平洋之间海陆热力差异及青藏高原的强烈影响，是气候系统非常重要的一个组成部分．

关键词：亚洲季风环流系统大气气候系统海陆热力差异气候变化气象仪器生活节奏

Variations on a Proof of a Borderline Bourgain-Brezis Sobolev Embedding Theorem

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Chinese Annals of Mathematics,Series B 2017年第1期38卷 235-252页

作者： Sagun CHANILLO Jean VAN SCHAFTINGEN Po-Lam YUNG Department of Mathematics Rutgers the State University of New Jersey 110 Frelinghuysen Road PiscatawayNJ08854USA institut de Recherche en Mathematique et en Physique Universite catholique de Louvain Chemin du Cyclotron 2 bte L7.01.011348 Louvain-la-NeuveBelgium Department of Mathematics the Chinese University of Hong KongShatin.Hong Kong

This paper offers a variant of a proof of a borderline Bourgain-Brezis Sobolev embedding theorem on R^n. The authors use this idea to extend the result to real hyperbolic spaces H^n.

关键词： Bourgain-Brezis inequalities Divergence-free vector fields Sobolev inequalities Real hyperbolic space

miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold E.Beyreuther F.-E.Brack F.Kroll J.Pawelke J.D.Schilz M.Schneider U.Schramm M.E.P.Umlandt K.Zeil T.Ziegler J.Metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum Freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

High performance computation on beam dynamics problems in high intensity compact cyclotrons

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Science China(Physics,Mechanics & Astronomy) 2011年第S2期54卷 249-254页

作者： ADELMANN Andreas Paul Scherrer institut Villigen CH-5234 Switzerland

This paper presents the research progress in the beam dynamics problems for future high intensity compact cyclotrons by utilizing the state-of-the-art high performance computation technology. A "Start-to-Stop" model, which includes both the interaction of the internal particles of a single bunch and the mutual interaction of neighboring multiple bunches in the radial direction, is established for compact cyclotrons with multi-turn extraction. This model is then implemented in OPAL-CYCL, which is a 3D object-oriented parallel code for large scale particle simulations in cyclotrons. In addition, to meet the running requirement of parallel computation, we have constructed a small scale HPC cluster system and tested its performance. Finally, the high intensity beam dynamics problems in the 100 MeV compact cyclotron, which is being constructed at CIAE, are studied using this code and some conclusions are drawn.

关键词： compact cyclotron space charge effects parallel computation beam dynamics cluster system

Carbon isotopic compositions of pore and matrix carbonates in carbonate nodules, and origin of carbonate formation

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Chinese Science Bulletin 2010年第26期55卷 2926-2929页

作者： LIU Lian YIN QiuZhen WU HaiBin GUO ZhengTang Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China institut d'Astronomie et de Geophysique G. Lemaitre Universite catholique de Louvain Chemin du Cyclotron 2 1348 Louvain-la-Neuve Bel gium

Carbon isotopes of pedogenic carbonate are often used to study paleoenvironments, but the existence of detrital carbonate changes the carbon isotopic composition. To develop an experimental method to determine existence of detrital carbonate in carbonate nodules, and to avoid it during isotope analysis, 23 pedogenic carbonate nodules in Miocene loess from the Loess Plateau of China were studied through micromorphology and carbon isotope analysis. The difference in carbon isotopic composition between matrix carbonate (B) and pore carbonate (A) (δ 13C(B-A)) ranges from 0.27‰ to 0.44‰ in nodules containing detrital carbonate and -0.16‰ to 0.13‰ in nodules where detrital carbonate is absent. The latter is within measurement error, but the former is beyond it. Here we propose an isotopic approach to determine if nodules contain detrital carbonate: if δ 13C(B-A) is within the measurement error, the nodules do not contain detrital carbonate, and vice versa. We suggest that it is better to analyze pore carbonate instead of matrix carbonate when using carbon isotope of carbonate nodules to reconstruct paleoenvironments.

关键词：碳同位素组成碳酸盐结核核基质中国黄土高原碳同位素分析起源测量误差同位素方法

RHIC束流能量扫描实验中正反粒子椭圆流的平均场势效应(英文)

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原子核物理评论 2015年第2期32卷 146-153页

作者：徐骏柯治明李锋 SONG Taesoo 刘鹤中国科学院上海应用物理研究所上海201800 cyclotron institutE AND DEPARTMENT OF PHYSICS AND ASTRONOMY TEXAS A&M UNIVERSITYCOLLEGE STATION FRANKFURT institut FOR ADVANCED STUDIES THEORETICAL PHYSICS JOHANN WOLFGANG GOETHE UNIVERSITAT 中国科学院大学北京100049

最近,STAR合作体在相对论重离子对撞机的束流能量扫描实验中观测到了正反粒子的椭圆流劈裂。基于输运模型,发现丰重子介质中正反粒子平均场势的不同可以解释其椭圆流的劈裂。利用Nambu-Jona-Lasinio模型描述相对论重离子碰撞的部分子相... 详细信息

最近,STAR合作体在相对论重离子对撞机的束流能量扫描实验中观测到了正反粒子的椭圆流劈裂。基于输运模型,发现丰重子介质中正反粒子平均场势的不同可以解释其椭圆流的劈裂。利用Nambu-Jona-Lasinio模型描述相对论重离子碰撞的部分子相,发现实验中正反粒子的相对椭圆流劈裂可以用来约束该模型中夸克矢量相互作用的耦合系数。这一发现对确定QCD相图的临界点位置和理解整个QCD的相结构有重要意义。

关键词：束流能量扫描 QCD相图椭圆流

Study effects of El Jadida—Casablanca industrial zone neighbouring areas

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Natural Science 2013年第8期5卷 880-887页

作者： Huberson Douo Bogbe Gogon Hassane Erramli Thierry Sauvage Claire Ramboz UniversitéFelix Houphouet Boigny d’ABIDJAN Cocody UFR SSMT Laboratoire de Physique Nucléaire et RadioprotectionAbi-djand’Ivoire Nuclear Physics and Techniques Laboratory Faculty of Sciences SemlaliaUniversity Cadi AyyadMarrakechMorocco CNRS/CEMHTI Site CyclotronOrléansFrance institut des Sciences de la Terre d’Orléans(ISTO) OrléansFrance

The analytical technique PIXE experiment for measuring light and heavy elements concentration inside different samples of soil and residual water collected in the region of Safi-El Jadida, where an industrial complex resided, was performed. The same method was used to investigate the presence of elements ranging from silicon to lead in different soils samples and seaweed collected upstream from the site of Safi-El Jadida industrial zone, inside lands and downstream of it, in the entrance of the Casablanca region. This study allows us to highlight the influence of activities of this industrial zone on the neighbouring areas the site.

关键词： PIXE Heavy And Light Elements Van De Graaff Accelerator Pollution Phosphate Industry Waste