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A Novel Sensing Imaging Equipment Under Extremely Dim Light for Blast Furnace Burden Surface:Starlight High-Temperature Industrial Endoscope
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作者 zhipeng chen Xinyi Wang +3 位作者 Weihua Gui Jilin Zhu Chunhua Yang Zhaohui Jiang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期893-906,共14页
Blast furnace(BF)burden surface contains the most abundant,intuitive and credible smelting information and acquiring high-definition and high-brightness optical images of which is essential to realize precise material... Blast furnace(BF)burden surface contains the most abundant,intuitive and credible smelting information and acquiring high-definition and high-brightness optical images of which is essential to realize precise material charging control,optimize gas flow distribution and improve ironmaking efficiency.It has been challengeable to obtain high-quality optical burden surface images under high-temperature,high-dust,and extremelydim(less than 0.001 Lux)environment.Based on a novel endoscopic sensing detection idea,a reverse telephoto structure starlight imaging system with large field of view and large aperture is designed.Combined with a water-air dual cooling intelligent self-maintenance protection device and the imaging system,a starlight high-temperature industrial endoscope is developed to obtain clear optical burden surface images stably under the harsh environment.Based on an endoscope imaging area model,a material flow trajectory model and a gas-dust coupling distribution model,an optimal installation position and posture configuration method for the endoscope is proposed,which maximizes the effective imaging area and ensures large-area,safe and stable imaging of the device in a confined space.Industrial experiments and applications indicate that the proposed method obtains clear and reliable large-area optical burden surface images and reveals new BF conditions,providing key data support for green iron smelting. 展开更多
关键词 Blast furnace(BF) burden surface extremely dim light industrial endoscope sensing imaging STARLIGHT
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Characteristics of the SOL ion-to-electron temperature ratio on the J-TEXT tokamak with different plasma configurations
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作者 李存凯 梁云峰 +16 位作者 江中和 周松 华建坤 阳杰 杨庆虎 Alexander KNIEPS Philipp DREWS 徐鑫 毛飞越 谢伟 杨雨桐 郭金龙 李杨波 任正康 陈志鹏 王能超 the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期13-21,共9页
Accurate measurement of the average plasma parameters in the edge region,including the temperature and density of electrons and ions,is critical for understanding the characteristics of the scrape-off layer(SOL) and d... Accurate measurement of the average plasma parameters in the edge region,including the temperature and density of electrons and ions,is critical for understanding the characteristics of the scrape-off layer(SOL) and divertor plasma transport in magnetically confined fusion research.On the J-TEXT tokamak,a multi-channel retarding field analyzer(RFA) probe has been developed to study average plasma parameters in the edge region under various poloidal divertor and island divertor configurations.The edge radial profile of the ion-to-electron temperature ratio,τ_(i/e),has been determined,which gradually decreases as the SOL ion self-collisionality,v_(SOL)*,increases.This is broadly consistent with what has been observed previously from various tokamak experiments.However,the comparison of experimental results under different configurations shows that in the poloidal divertor configuration,even under the same v_(SOL)*,τ_(i/e) in the SOL region becomes smaller as the distance from the X-point to the target plate increases.In the island divertor configuration,τ_(i/e) near the O-point is higher than that near the X-point at the same v_(SOL)*,and both are higher than those in the limiter configuration.These results suggest that the magnetic configuration plays a critical role in the energy distributions between electrons and ions at the plasma boundary. 展开更多
关键词 ion temperature island divertor poloidal divertor retarding field analyzer(RFA)probe
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J-TEXT achievements in turbulence and transport in support of future device/reactor
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作者 zhipeng chen Zhangsheng HUANG +22 位作者 Min JIANG Ting LONG Lu WANG Weixin GUO Zhoujun YANG Hai LIU Tao LAN Kaijun ZHAO Yuhong XU Rui KE Youwen SUN Hanhui LI Wen HE Ge ZHUANG Yuejiang SHI Wulyu ZHONG Yonghua DING Yunfeng LIANG Wenjing TIAN Xin XU Guodong ZHANG M.S.HUSSAIN Patrick H.DIAMOND 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第11期1-21,共21页
Following the reconstruction of the TEXT tokamak at Huazhong University of Science and Technology in China, renamed as J-TEXT, a plethora of experimental and theoretical investigations has been conducted to elucidate ... Following the reconstruction of the TEXT tokamak at Huazhong University of Science and Technology in China, renamed as J-TEXT, a plethora of experimental and theoretical investigations has been conducted to elucidate the intricacies of turbulent transport within the tokamak configuration. These endeavors encompass not only the J-TEXT device's experimental advancements but also delve into critical issues pertinent to the optimization of future fusion devices and reactors. The research includes topics on the suppression of turbulence, flow drive and damping, density limit, non-local transport, intrinsic toroidal flow, turbulence and flow with magnetic islands, turbulent transport in the stochastic layer, and turbulence and zonal flow with energetic particles or helium ash. Several important achievements have been made in the last few years, which will be further elaborated upon in this comprehensive review. 展开更多
关键词 J-TEXT tokamak TURBULENCE transport flow
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Suppression of the m/n=2/1 tearing mode by electron cyclotron resonance heating on J-TEXT
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作者 方建港 陈忠勇 +13 位作者 严伟 王能超 毛飞越 罗蔷 玄子健 陈曦璇 任正康 张峰 黄梅 夏冬辉 杨州军 陈志鹏 丁永华 the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第8期8-17,共10页
Stabilization of tearing modes and neoclassical tearing modes is of great importance for tokamak operation.Electron cyclotron waves(ECWs)have been extensively used to stabilize the tearing modes with the virtue of hig... Stabilization of tearing modes and neoclassical tearing modes is of great importance for tokamak operation.Electron cyclotron waves(ECWs)have been extensively used to stabilize the tearing modes with the virtue of highly localized power deposition.Complete suppression of the m/n=2/1 tearing mode(TM)by electron cyclotron resonance heating(ECRH)has been achieved successfully on the J-TEXT tokamak.The effects of ECW deposition location and power amplitude on the 2/1 TM suppression have been investigated.It is found that the suppression is more effective when the ECW power is deposited closer to the rational surface.As the ECW power increases to approximately 230 k W,the 2/1 TM can be completely suppressed.The island rotation frequency is increased when the island width is reduced.The experimental results show that the local heating inside the magnetic island and the resulting temperature perturbation increase at the O-point of the island play dominant roles in TM suppression.As the ECW power increases,the 2/1 island is suppressed to smaller island width,and the flow shear also plays a stabilizing effect on small magnetic islands.With the stabilizing contribution of heating and flow shear,the 2/1 TM can be completely suppressed. 展开更多
关键词 tearing mode electron cyclotron resonant heating tearing mode suppression
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Investigation of the J-TEXT plasma events by k-means clustering algorithm 被引量:1
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作者 李建超 张晓卿 +11 位作者 张昱 Abba Alhaji BALA 柳惠平 周帼红 王能超 李达 陈忠勇 杨州军 陈志鹏 董蛟龙 丁永华 the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第8期38-43,共6页
Various types of plasma events emerge in specific parameter ranges and exhibit similar characteristics in diagnostic signals,which can be applied to identify these events.A semisupervised machine learning algorithm,th... Various types of plasma events emerge in specific parameter ranges and exhibit similar characteristics in diagnostic signals,which can be applied to identify these events.A semisupervised machine learning algorithm,the k-means clustering algorithm,is utilized to investigate and identify plasma events in the J-TEXT plasma.This method can cluster diverse plasma events with homogeneous features,and then these events can be identified if given few manually labeled examples based on physical understanding.A survey of clustered events reveals that the k-means algorithm can make plasma events(rotating tearing mode,sawtooth oscillations,and locked mode)gathering in Euclidean space composed of multi-dimensional diagnostic data,like soft x-ray emission intensity,edge toroidal rotation velocity,the Mirnov signal amplitude and so on.Based on the cluster analysis results,an approximate analytical model is proposed to rapidly identify plasma events in the J-TEXT plasma.The cluster analysis method is conducive to data markers of massive diagnostic data. 展开更多
关键词 K-MEANS cluster analysis plasma event machine learning
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Disruption prediction based on fusion feature extractor on J-TEXT
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作者 郑玮 薛凤鸣 +9 位作者 陈忠勇 沈呈硕 艾鑫坤 钟昱 王能超 张明 丁永华 陈志鹏 杨州军 潘垣 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期12-23,共12页
Predicting disruptions across different tokamaks is necessary for next generation device.Future large-scale tokamaks can hardly tolerate disruptions at high performance discharge,which makes it difficult for current d... Predicting disruptions across different tokamaks is necessary for next generation device.Future large-scale tokamaks can hardly tolerate disruptions at high performance discharge,which makes it difficult for current data-driven methods to obtain an acceptable result.A machine learning method capable of transferring a disruption prediction model trained on one tokamak to another is required to solve the problem.The key is a feature extractor which is able to extract common disruption precursor traces in tokamak diagnostic data,and can be easily transferred to other tokamaks.Based on the concerns above,this paper presents a deep feature extractor,namely,the fusion feature extractor(FFE),which is designed specifically for extracting disruption precursor features from common diagnostics on tokamaks.Furthermore,an FFE-based disruption predictor on J-TEXT is demonstrated.The feature extractor is aimed to extracting disruption-related precursors and is designed according to the precursors of disruption and their representations in common tokamak diagnostics.Strong inductive bias on tokamak diagnostics data is introduced.The paper presents the evolution of the neural network feature extractor and its comparison against general deep neural networks,as well as a physics-based feature extraction with a traditional machine learning method.Results demonstrate that the FFE may reach a similar effect with physics-guided manual feature extraction,and obtain a better result compared with other deep learning methods. 展开更多
关键词 feature extractor disruption prediction deep learning tokamak diagnostics
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Design of new resonant magnetic perturbation coils on the J-TEXT tokamak
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作者 黄卓 周松 +11 位作者 樊金荣 李达 饶波 王能超 丁永华 毛飞越 黄名响 田微 陈忠勇 陈志鹏 梁云峰 the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第11期142-149,共8页
The resonant magnetic perturbation(RMP)system is a powerful auxiliary system on tokamaks.On the J-TEXT tokamak,a set of new in-vessel coils is designed to enhance the amplitude of the RMP.The new coils are designed to... The resonant magnetic perturbation(RMP)system is a powerful auxiliary system on tokamaks.On the J-TEXT tokamak,a set of new in-vessel coils is designed to enhance the amplitude of the RMP.The new coils are designed to be two-turn saddle coils.These two-turn saddle coils have been optimized in terms of their structure,support,and protection components to overcome the limitations of the narrow in-vessel space,resulting in a compact coil module that can be accommodated in the vessel.To verify the feasibility of this design,an electromagnetic simulation is performed to investigate the electrical parameters and the generated field of the coils.A multi-field coupled simulation is performed to investigate the capacity of heat dissipation.As a result of these efforts,the new RMP coils have been successfully installed on the J-TEXT tokamak.It has significantly enhanced the RMP amplitude and been widely applied in experiments. 展开更多
关键词 fusion engineering TOKAMAK resonant magnetic perturbation coil multi-field coupled simulation(Some fioures may appeari in colour only in the online iournal)
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A New Device Concept of Magnetic Confinement Deuterium-Deuterium Fusion
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作者 潘垣 武松涛 +8 位作者 王之江 陈志鹏 许敏 饶波 朱平 杨勇 张明 丁永华 夏冬辉 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第10期39-43,共5页
A two-stage cascade magnetic compression scheme based on field reversed configuration plasma is proposed.The temperature and density of plasma before and after magnetic compression are analyzed.In addition,the suppres... A two-stage cascade magnetic compression scheme based on field reversed configuration plasma is proposed.The temperature and density of plasma before and after magnetic compression are analyzed.In addition,the suppression of the two-fluid effect and the finite Larmor radius effect on the tilting mode and the rotating mode of major magnetic hydrodynamic instability is studied,and finally,the key physical and engineering parameters of the deuterium-deuterium fusion pulse device are introduced.Further analysis shows that the fusion neutrons can be produced at an energy flux of more than 2 MW/m^(2)per year,which meets the material testing requirements for the fusion demonstration reactor(DEMO).If the recovery of magnetic field energy is taken into account,net energy outputs may be achieved,indicating that the scheme has a potential application prospect as a deuterium-deuterium pulse fusion energy. 展开更多
关键词 SCHEME reversed ROTATING
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Cytological and transcriptional insights of late-acting selfincompatibility in tea plants(Camellia sinensis)
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作者 Shengrui Liu Rui Guo +7 位作者 Jingjuan Zhao Enhua Xia Yongning Tao Qianqian Zhou zhipeng chen Hui Xie Junyan Zhu Chaoling Wei 《Beverage Plant Research》 2023年第1期177-187,共11页
Self-incompatibility(SI)is a kind of plant fertilization obstacle,which can prevent the harmful effects of inbreeding decline,but it hinders the breeding of inbred lines.Tea plants have SI and long-term cross-pollinat... Self-incompatibility(SI)is a kind of plant fertilization obstacle,which can prevent the harmful effects of inbreeding decline,but it hinders the breeding of inbred lines.Tea plants have SI and long-term cross-pollination,which limits the progress of genetic research and variety improvement.However,the mechanism of SI in tea plants is still a mystery.Herein,microscopic observation showed that the pollen tube could pass through the base of style and enter the ovary cavity after 48 h of self-pollination at different flowering stages,and the SI intensity at bud stage and full bloom stage was lower than initial bloom stage.RNA-seq analysis showed that 1,463 and 1,409 differentially expressed genes(DEGs)were associated with low SI at bud stage and full bloom stage,respectively,and 507 DEGs were associated with SI at initial bloom stage.The results of qRT-PCR validation of 20 DEGs were consistent with the RNA-seq data.Furthermore,CsRNS,CsSRKL5 and CsSRKL8 specifically expressed in style,which may be related to the low SI at bud stage,and three CsACC genes may be related to the low SI at full bloom stage.The results provide useful information for understanding the mechanism of SI in tea plants. 展开更多
关键词 sinensis) BREEDING hinder
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肿瘤相关成纤维细胞对于免疫细胞的调节作用研究现状 被引量:3
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作者 慕广 张文豪 +2 位作者 黄晶晶 陈志鹏 王俊 《中国肺癌杂志》 CAS CSCD 北大核心 2022年第3期207-213,共7页
肿瘤相关成纤维细胞(cancer-associated fibroblasts,CAFs)和肿瘤浸润性免疫细胞是肿瘤微环境(tumor microenvironment,TME)中重要的组成成分。二者在肿瘤微环境中相互通信,在肿瘤的发生和发展中发挥着重要作用。CAFs具有很大的异质性,... 肿瘤相关成纤维细胞(cancer-associated fibroblasts,CAFs)和肿瘤浸润性免疫细胞是肿瘤微环境(tumor microenvironment,TME)中重要的组成成分。二者在肿瘤微环境中相互通信,在肿瘤的发生和发展中发挥着重要作用。CAFs具有很大的异质性,不同的CAFs亚群存在着不同的功能。同时其又可以通过分泌多种细胞因子、趋化因子等方式实现对肿瘤浸润性免疫细胞的调节,从而进一步影响肿瘤的发生、发展、侵袭、转移等生物学行为。本文对国内外近年来有关CAFs在TME中对浸润性免疫细胞调节作用的研究现状作一综述。 展开更多
关键词 肿瘤微环境 肿瘤相关成纤维细胞 肿瘤浸润型免疫细胞 免疫调节 肿瘤免疫
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Pore-scale mechanisms and characterization of light oil storage in shale nanopores:New method and insights 被引量:4
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作者 Wei Dang Haikuan Nie +7 位作者 Jinchuan Zhang Xuan Tang Shu Jiang Xiaoliang Wei Yang Liu Fengqin Wang Pei Li zhipeng chen 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第5期50-58,共9页
A new method is proposed to analyze the pore-scale mechanisms and characterization of light oil storage in shale nanopores,which is based on the Hydrocarbon Vapor Adsorption(HVA)and Pore Calculation Model(PCM).First,t... A new method is proposed to analyze the pore-scale mechanisms and characterization of light oil storage in shale nanopores,which is based on the Hydrocarbon Vapor Adsorption(HVA)and Pore Calculation Model(PCM).First,the basic principle of the HVA-PCM method is introduced,and the experimental/mathematical analysis processes are given.Then,the HVA-PCM method is applied to shale samples to analyze the mechanisms and characterization of light oil storage in shale nanopores.The results provide insights into the pore-scale oil storage mechanisms,oil storage structure,oil film thickness,oil distribution within different sized pores,and the oil storage state.Finally,the advantages and limitations of the HVA-PCM method are discussed,and suggestions for further improvement are proposed.Overall,the HVA-PCM method is a powerful tool for extracting quantitative information on the light oil storage in shale nanopores. 展开更多
关键词 Shale oil Storage mechanisms Storage characterization Hydrocarbon vapor adsorption
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Overview of the J-TEXT progress on RMP and disruption physics 被引量:3
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作者 Yonghua DING Zhongyong chen +20 位作者 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 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第12期19-30,共12页
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 m... 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. 展开更多
关键词 resonant magnetic perturbation (RMP) massive gas injection (MGI) runaway current DISRUPTION J-TEXT
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软件工程专业物联网及嵌入式系统方向教学研究(英文) 被引量:5
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作者 Ce Zhang Dianhui Chu +3 位作者 Fanchao Meng zhipeng chen Xinsheng Wang Weigong Lyu 《计算机教育》 2016年第8期19-25,共7页
当前,软件工程专业如何适应物联网及嵌入式系统领域的巨大需求,是一个亟待解决的问题。基于该问题,本文提出一个新方法进行该专业的课程安排及学习计划。首先,结合物联网基础设施技术,在软件工程教学中融入物联网及嵌入式系统的教学内容... 当前,软件工程专业如何适应物联网及嵌入式系统领域的巨大需求,是一个亟待解决的问题。基于该问题,本文提出一个新方法进行该专业的课程安排及学习计划。首先,结合物联网基础设施技术,在软件工程教学中融入物联网及嵌入式系统的教学内容,分析学生惧怕物联网及嵌入式系统发展的原因;然后,提出循序渐进的由低级别嵌入式系统开发到高级别应用软件开发的学习路径;最后,分别剖析物联网及嵌入式系统方向的就业选择和职业规划。 展开更多
关键词 软件工程 物联网 嵌入式系统 方向课程 技术路线图
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Dust Distribution Study at the Blast Furnace Top Based on k-Sε-u_(p)Model 被引量:2
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作者 zhipeng chen Zhaohui Jiang +2 位作者 Chunjie Yang Weihua Gui Youxian Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第1期121-135,共15页
The dust distribution law acting at the top of a blast fumace(BF)is of great significance for understanding gas flow distribution and mitigating the negative influence of dust particles on the accuracy and service lif... The dust distribution law acting at the top of a blast fumace(BF)is of great significance for understanding gas flow distribution and mitigating the negative influence of dust particles on the accuracy and service life of detection equipment.The harsh environment inside a BF makes it difficult to describe the dust disthibution.This paper adresses this problem by proposing a dust distribution k-Sε-u_(p)model based on interphase(gas-powder)coupling.The proposed model is coupled with a k-Sεmodel(which describes gas flow movement)and a u_(p)model(which depicts dust movement).First,the kinetic energy equation and turbulent dissipation rate equation in the k-Sεmodel are established based on the modeling theory and single Green-function two scale direct interaction approximation(SGF-TSDIA)theory.Second,a dust particle mnovement u_(p)model is built based on a force analysis of the dust and Newton's laws of motion.Finally,a coupling factor that descibes the interphase interaction is proposed,and the k-Sε-u_(p)model,with clear physical meaning.ligorous mathematical logic,and adequate generality,is dleveloped.Siumulation results and o-site verification show that the k-Sε-u_(p)model not only has high precision,but also reveals the aggregate distribution features of the dust,which are helpful in optimizing the installation position of the detection equipment and imnproving its accuracy and service life. 展开更多
关键词 Blast furnace(BF) dust movement interphase interaction modeling theory turbulent flow two-scale direct interaction approximation(TSDIA)
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Water-Jet Cavitation Shock Bulging as Novel Microforming Technique 被引量:2
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作者 Fuzhu Li Haiyang Fan +5 位作者 Yuqin Guo zhipeng chen Xu Wang Ruitao Li Hong Liu Yun Wang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第1期199-209,共11页
With the continuous expansion of the application range of microelectromechanical systems,microdevice forming technology has achieved remarkable results.However,it is challenging to develop new microforming processes t... With the continuous expansion of the application range of microelectromechanical systems,microdevice forming technology has achieved remarkable results.However,it is challenging to develop new microforming processes that are low cost,environmentally friendly,and highly flexible;the high-energy shock wave in a cavitation bubble's collapse process is used as the loading force.Herein,a new process for the microbulging of the water-jet cavitation is proposed.A series of experiments involving the water-jet cavitation shock microbulging process for TA2 titanium foil is performed on an experimental system.The microforming feasibility of the water-jet cavitation is investigated by characterizing the shape of the formed part.Subsequently,the effects of the main parameters of the water-jet cavitation on the bulging profile,forming depth,surface roughness,and bulging thickness distribution of TA2 titanium foil are revealed.The results show that the plastic deformation increases nonlinearly with the incident pressure.When the incident pressure is 20 MPa,the maximum deformation exceeds 240 pm,and the thickness thinning ratio changes within 10%.The microbulging feasibility of water-jet cavitation is verified by this phenomenon. 展开更多
关键词 Water-jet cavitation Microbulging TA2 titanium foil Shock forming Plastic deformation
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Modification of pillared MFI zeolite nanosheets by nitridation with tailored activity in benzylation of mesitylene and benzyl alcohol 被引量:1
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作者 zhipeng chen Jiajin Huang +4 位作者 Qiaowen Mu Huiyong chen Feng Xu Yanxiong Fang Baoyu Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第8期1981-1987,共7页
The modification of pillared MFI zeolites was performed by nitridation of silica pillared MFI zeolite nanosheets under NH3 atmosphere with different time. The resultant zeolites were characterized by a complementary c... The modification of pillared MFI zeolites was performed by nitridation of silica pillared MFI zeolite nanosheets under NH3 atmosphere with different time. The resultant zeolites were characterized by a complementary combination of X-ray power diffraction(XRD), scanning electron microscopy(SEM),transmission electron microscopy(TEM), pyridine-IR spectroscopy and N2 adsorption–desorption isotherms. The analyses showed that the nitridation didn’t destroy the crystallinity and specific surface area of zeolites, and the acidity of zeolites can be tailored by tuning the time of nitridation, resulting in the different concentration ratios of Br?nsted-to-Lewis(B/L) acid sites. Moreover, the nitrided zeolites exhibited high selectivity to 2-benzyl-1,3,5-trimethylbenzene than parent silica pillared MFI zeolite nanosheets in benzylation of mesitylene with benzyl alcohol. A balance between Br?nsted acid sites and Lewis acid sites can inhibit the self-etherification of benzyl alcohol and enhance the selectivity of alkylated product. These experimental data implied that nitridation was an effective method to modulate the acidity of zeolites and the synergy between Br?nsted acid sites and Lewis acid sites was a decisive factor to determine the selectivity. 展开更多
关键词 MFI zeolite Pillar NITRIDATION BENZYLATION
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Toroidal component of velocity for geodesic acoustic modes in the edge plasmas of the J-TEXT tokamak 被引量:1
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作者 Yaoyu Xie Kaijun Zhao +15 位作者 zhipeng chen Jiaqi Dong Kimitaka Itoh Zhongyong chen Yuejiang Shi Yonghua Ding Jun cheng Longwen Yan Hai Liu Zhifeng cheng Zhoujun Yang Nengchao Wang Lu Wang Jianqiang Xu Yunfeng Liang J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2021年第10期112-119,共8页
The toroidal component of the velocity for geodesic acoustic modes(GAMs)is first demonstrated.Multiple Langmuir probe arrays set up near the top tokamak of the J-TEXT were utilized for this study.A significant peak at... The toroidal component of the velocity for geodesic acoustic modes(GAMs)is first demonstrated.Multiple Langmuir probe arrays set up near the top tokamak of the J-TEXT were utilized for this study.A significant peak at the GAM frequency is observed in Mach number fluctuations.The toroidal velocity for the GAMs is estimated as 10–100 ms-1 and increases with the poloidal velocity.The ratio of toroidal component to the poloidal one of the velocity is mainly located in the interval between 0.3 and 1.0.With higher safety factors q,the ratio almost does not change with decreasing the safety factor,whereas it goes up sharply at low q.The coherencies between poloidal electric fields and Mach number fluctuations in turbulence frequency bands are also evaluated,and are higher than those between radial electric fields and Mach number fluctuations. 展开更多
关键词 zonal flow geodesic acoustic mode TOKAMAK return flow Mach number
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The application of limiter target electrostatic measurement system in J-TEXT tokamak
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作者 Jie YANG zhipeng chen +6 位作者 Hai LIU Tong WANG Mingcong ZHU Zebao SONG Zhijiang WANG Ge ZHUANG Yonghua DING 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第10期40-46,共7页
The limiter target electrostatic measurement system including limiter grounding current sensors and Langmuir probes have been newly developed for the measurement of the limiter target area on the Joint-Texas Experimen... The limiter target electrostatic measurement system including limiter grounding current sensors and Langmuir probes have been newly developed for the measurement of the limiter target area on the Joint-Texas Experimental tokamak (J-TEXT). Current sensors fixed between graphite limiters and the vacuum vessel walls are used to measure the currents between limiters and vessel wall. Simultaneously, a rectangular poloidal array containing 54 Langmuir probes is embedded in the graphite tiles of limiters for a more localized measurement. Based on this system, the effect of both the plasma’s inherent behavior, including plasma motion and the 2/1 tearing mode, and the electrode biasing on probe and sensor signals have been observed and analyzed in the experiments. 展开更多
关键词 LIMITER TARGET ELECTROSTATIC FLUCTUATIONS LANGMUIR probe edge current J-TEXT
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Design and first result of combined Langmuir-magnetic probe on J-TEXT tokamak
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作者 Qinghu YANG zhipeng chen +12 位作者 Zhigang HAO Yangming ZHAO Xin XU Shuhao LI Jie YANG Wei YAN Zhonghe JIANG Zhongyong chen Nengchao WANG Zhoujun YANG Yuan PAN Yonghua DING the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第5期39-47,共9页
In order to measure boundary electrostatic and magnetic fluctuations simultaneously,a combined Langmuir-magnetic probe(CLMP)has been designed and built on joint-Texas experimental tokamak.The probe consists of 8 graph... In order to measure boundary electrostatic and magnetic fluctuations simultaneously,a combined Langmuir-magnetic probe(CLMP)has been designed and built on joint-Texas experimental tokamak.The probe consists of 8 graphite probe pins and a 3D magnetic probe,driven by a mechanical pneumatic device.By means of simulation,the shielding effect of the graphite sleeve on the magnetic fluctuation signal is explored,and the influence of the eddy current was reduced by cutting the graphite sleeve.In the experiment,it has been verified that the mutual inductance of electromagnetic signals can be ignored,and a 70–90 k Hz electromagnetic mode is observed around the last closed magnetic surface.The establishment of CLMP provides data for the exploration of the coupling of electrostatic and magnetic fluctuations. 展开更多
关键词 J-TEXT Langmuir probe magnetic probe eddy current effect electromagnetic mode
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Study of the spectrum effect on the threshold of resonant magnetic perturbation penetration on J-TEXT
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作者 Feiyue MAO Nengchao WANG +19 位作者 Zhuo HUANG Zhengkang REN Song ZHOU chengshuo SHEN Xiaoyi ZHANG Ying HE Qi ZHANG Ruo JIA Chuanxu ZHAO Yangbo LI Bo HU Da Li Abba Alhaji BALA zhipeng chen Zhongyong chen Zhoujun YANG Yunfeng LIANG Yonghua DING Yuan PAN the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第12期16-25,共10页
The spectrum effect on the penetration of resonant magnetic perturbation(RMP) is studied with upgraded in-vessel RMP coils on J-TEXT.The poloidal spectrum of the RMP field,especially the amplitudes of 2/1 and 3/1 comp... The spectrum effect on the penetration of resonant magnetic perturbation(RMP) is studied with upgraded in-vessel RMP coils on J-TEXT.The poloidal spectrum of the RMP field,especially the amplitudes of 2/1 and 3/1 components,can be varied by the phase difference between the upper and lower coil rows,ΔΦ=Φ_(top)-Φ_(bottom),where Φ_(top)and Φ_(bottom)are the toroidal phases of the n=1 field of each coil row.The type of RMP penetration is found to be related to ΔΦ,including the RMP penetration of either 2/1 or 3/1 RMP and the successive penetrations of 3/1 RMP followed by the 2/1 RMP.For cases with penetration of only one RMP component,the penetration thresholds measured by the corresponding resonant component are close for variousΔΦ.However,the 2/1 RMP penetration threshold is significantly reduced if the 3/1 locked island is formed in advance.The changes in the rotation profile due to 3/1 locked island formation could partially contribute to the reduction of the 2/1 thresholds. 展开更多
关键词 TOKAMAK error field resonant magnetic perturbation mode penetration spectrum analysis
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