检索结果-南通市图书馆

Overview of the j-text progress on RMP and disruption physics

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2018年第12期20卷 19-30页

作者： Yonghua DING Zhongyong CHEN Zhipeng CHEN Zhoujun YANG Nengchao WANG Qiming HU Bo RAO jie CHEN Zhifeng CHENG Li GAO Zhonghe jIANG Lu WANG Zhijiang WANG Xiaoqing ZHANG Wei ZHENG Ming ZHANG Ge ZHUANG Qingquan YU Yunfeng LIANG Kexun YU Xiwei HU Yuan PAN Kenneth William GENTLE International joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People＇s Republic of China Max-Planck-Institut fur Plasmaphysik 85748 GarchingGermany Forschungszentrum julich GmbH Institut fur Energie-und Klimaforschung-Plasmaphysik52425 JulichGermany Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People＇s Republic of China Institute for Fusion Studies University of Texas at AustinAustinTX 78712United States of America

The j-text tokamak has been operated for ten years since its first plasma obtained at the end of 2007. The diagnostics development and main modulation systems, i.e. resonant magnetic perturbation （RMP） systems and massive gas injection （MGI） systems, will be introduced in this paper. Supported by these efforts, j-text has contributed to research on several topics, especially on RMP physics and disruption mitigation. Both experimental and theoretical research show that RMP could lock, suppress or excite the tearing modes, depending on the RMP amplitude, frequency difference between RMP and rational surface rotation, and initial stabilities. The plasma rotation, particle transport and operation region are influenced by the RMP. Utilizing the MGI valves, disruptions have been mitigated with pure He, pure Ne, and a mixture of He and Ar （9：1）. A significant runaway current plateau could be generated with moderate amounts of Ar injection. The RMP has been shown to suppress the generation of runaway current during disruptions.

关键词： resonant magnetic perturbation (RMP) massive gas injection (MGI) runaway current disruption j-text

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

在线全文

学校读者我要写书评

暂无评论

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

Observation of Doppler shift f_(D) modulated by the internal kink mode using conventional reflectometry in the EAST tokamak

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2024年第3期26卷 1-9页

作者：李恭顺张涛耿康宁文斐叶凯萱徐立清朱翔张学习钟富彬周振杨书琪周子强喻琳兰婷王守信提昂张寿彪刘海庆李国强高翔 the EAST team Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People's Republic of China Advanced Energy Research Center Shenzhen UniversityShenzhen 518060People's Republic of China University of Science and Technology of China Hefei 230026People's Republic of China

In this paper we present a new experimental observation using a conventional reflectometry technique,poloidal correlation reflectometry(PCR),in the Experimental Advanced Superconducting Tokamak(EAST).The turbulence spectrum detected by the PCR system exhibits an asymmetry and induced Doppler shift f_(D)during the internal kink mode(IKM)rotation *** Doppler shift f_(D)is the target measurement of Doppler reflectometry,but captured by conventional *** show that the Doppler shift f_(D)is modulated by the periodic changes in the effective angle between the probing wave and cutoff layer normal,but not by plasma *** fishbone mode and saturated long-lived mode are typical IKMs,and this modulation phenomenon is observed in both ***,the value of the Doppler shift f_(D)is positively correlated with the amplitude of the IKM,even when the latter is ***,the positive and negative frequency components of the Doppler shift f_(D)can be asymmetric,which is related to the plasma configuration.A simulated analysis is performed by ray tracing to verify these *** results establish a clear link between f_(D)and IKM rotation,and are helpful for studying the characteristics of IKM and related physical phenomena.

关键词： microwave reflectometry Doppler shift internal kink mode

Experimental study of core MHD behavior and a novel algorithm for rational surface detection based on profile reflectometry in EAST

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2024年第3期26卷 66-75页

作者：叶凯萱周振张涛马九阳王嵎民李恭顺耿康宁吴茗甫文斐黄佳张洋邵林明杨书琪钟富彬高善露喻琳周子强向皓明韩翔张寿彪李国强高翔 the EAST team Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031People's Republic of China University of Science and Technology of China Hefei 230026People's Republic of China Hebei Key Laboratory of Compact Fusion Langfang 065001Peoples Republic of China ENN Science and Technology Development Co. Ltd.Langfang 065001Peoples Republic of China Advanced Energy Research Center Shenzhen UniversityShenzhen 518060People's Republic of China

Microwave reflectometry is a powerful diagnostic that can measure the density profile and localized turbulence with high spatial and temporal resolution and will be used in ITER,so understanding the influence of plasma perturbations on the reflect signal is *** characteristics of the reflect signal from profile reflectometry,the time-of-flight(TOF)signal associated with the MHD instabilities,are investigated in *** a 1D full-wave simulation code by the Finite-DifferenceTime-Domain(FDTD)method,it is well validated that the local density flattening could induce the discontinuity of the simulated TOF signal and an obvious change of reflect *** TOF signals under different types of MHD instabilities(sawtooth,sawtooth precursors and tearing mode)are studied in detail and show agreement with the *** new improved algorithms for detecting and localizing the radial positions of the low-order rational surface,the cross-correlation and gradient threshold(CGT)method and the 2D convolutional neural network approach(CNN)are presented for the first *** is concluded that TOF signal analysis from profile reflectometry can provide a straightforward and localized measurement of the plasma perturbation from the edge to the core simultaneously and may be a complement or correction to the q-profile control,which will be beneficial for the advanced tokamak operation.

关键词： MHD instabilities profile reflectometry rational surface detection convolutional neural network(CNN) EAST tokamak

在线全文

学校读者我要写书评

暂无评论

鸟之歌

中学生英语 2024年第25期 36-37页

作者： team Pitara 侯怡

人类高兴的时候会说话，难过的时候也会说话；生气时会说话，看到美好的事物时也会说话；甚至无话可说时，也会试着说话。鸣禽亦是如此。它们唱歌是为了告诉那些邻居和陌生同类，哪儿是它们的家。或者，它们会唱歌以警告其他鸟类，敌人...

人类高兴的时候会说话，难过的时候也会说话；生气时会说话，看到美好的事物时也会说话；甚至无话可说时，也会试着说话。鸣禽亦是如此。它们唱歌是为了告诉那些邻居和陌生同类，哪儿是它们的家。或者，它们会唱歌以警告其他鸟类，敌人就在附近。在交配的季节，雄鸟会深情地鸣叫，因为它们想让雌鸟喜欢它们。麻雀、鹦鹉、画眉、噪鹃，甚至乌鸦，都属于鸣禽。世界上将近一半的鸟类都是鸣禽。全世界大约有4000种鸣禽，它们被归为不同的科。鸣禽之所以能唱歌，是因为它们有一个极好且功能强大的发声器官，叫做鸣管。

关键词：

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

破坏公私财物可不行

中国少年儿童 2024年第3期 36-37页

作者：唐玥 team-WOLF(图) 不详

大圣提醒:总有一些人漠视法律规定,通过破坏、损毁公私财物的方式发泄自己的情绪或为自己谋利。比如,在公共设施上乱涂乱画、在楼宇间贴小广告、毁坏护栏等。故意毁坏公私财物,数额较小、情节较轻的,属一般违法行为,按照《治安管理处罚... 详细信息

大圣提醒:总有一些人漠视法律规定,通过破坏、损毁公私财物的方式发泄自己的情绪或为自己谋利。比如,在公共设施上乱涂乱画、在楼宇间贴小广告、毁坏护栏等。故意毁坏公私财物,数额较小、情节较轻的,属一般违法行为,按照《治安管理处罚法》规定,处五日以上十日以下拘留,可并处五百元以下罚款;情节较重的,处十日以上十五日以下拘留,可并处一千元以下罚款。

关键词：公私财物一般违法行为情节较轻《治安管理处罚法》公共设施并处拘留罚款