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Effects of V and Zr Additions on Microstructures and Mechanical Properties of Nb-Ti-Al-Base Alloys

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稀有金属材料与工程 2009年第A03期38卷 5-7页

作者： Bai Run Zheng Xin Li Zhongkui Wang donghui xia Mingxing Northwest Institute for Nonferrous Metal Research Xi＇an 710016 China

Microstructures and mechanical properties of Nb-32Ti-7Al alloys containing different V and Zr contents were investigated. The microstructures were characterized using optical microscopy and scanning electron microscopy (SEM). The alloy with V and Zr presents single phase Nb solid solution (Nbss). Tensile testing was carried out at room temperature and 1373 K. The results show that these alloys have good ductility at room temperature. The strengths at room and high temperature increase with the addition of V and Zr, but the room temperature ductility decrease.

关键词：力学性能光学显微镜铌扫描电子显微镜

Electromagnetic dispersion characteristics of a high energy electron beam guided with an ion channel

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Plasma Science and Technology 2017年第2期19卷 20-27页

作者： Jixiong xiaO Zhong ZENG Zhijiang WANG donghui xia Changhai LIU Institute of fusion and plasma research Huazhong University of Science and Technology Wuhan 430074 People＇s Republic of China

Taking self-fields into consideration, dispersion properties of two types of electromagnetic modes for a high energy electron beam guided with an ion channel are investigated by using the linear perturbation theory. The dependences of the dispersion frequencies of electromagnetic waves on the electron beam radius, betatron frequency and boundary current are revealed. It is found that the electron beam radius and betatron frequency have different influences on the electromagnetic waves dispersion behavior by compared with the previous works. As the boundary current is taken into account, the TM modes will have two branches and a lowfrequency branch emerged as the new branch in strong ion channel case. This new branch has similar dispersion behavior to the betatron modes. For TE modes, there are two branches and they have different dispersion behaviors in strong ion channel case. However, in weak ion channel case, the dispersion behaviors for both of the low frequency and high frequency branches are similar.

关键词： dispersion behavior electromagnetic eigenmodes betatron oscillation ion channel

Investigation on the multi-hole directional coupler for power measurement of the J-TEXT ECRH system

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Plasma Science and Technology 2022年第6期24卷 196-205页

作者： Wenting WENG donghui xia Yizhe TIAN Xixuan CHEN Zhijiang WANG Yuan PAN The 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

Power measurement is necessary for an electron cyclotron resonance heating(ECRH)*** directional coupler method has been put forward to monitor high-power microwave from gyrotrons in real time.A multi-hole directional coupler has been designed and manufactured for the 105 GHz/500 kW ECRH system on the J-TEXT *** the design process,we established the relationships between hole parameters and coupling characteristics based on the multi-hole coupling method and small-hole coupling ***-power tests have been carried *** results indicated the reasonability of the theoretical design and practicality of the fabricated directional *** of test errors have been discussed in detail,and the influences of spurious modes on the directional couplers have been emphatically analyzed.

关键词： directional couplers power measurement ECRH system

Study of a 105 GHz short-pulse dummy load for the electron cyclotron resonance heating system with the quasi-optical method

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Plasma Science and Technology 2022年第10期24卷 139-146页

作者： Shouqi XIONG donghui xia Mei HUANG Gangyu CHEN Wenting WENG Guoyao FAN Yuan PAN 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 Southwestern Institute of Physics Chengdu 610041People's Republic of China

The accurate power measurement is important for an ECRH system in *** dummy load is designed and developed for the measurement of the millimeter wave *** work analyzes the dummy load based on the quasi-optical method and the ray tracing *** reflectivity and thermal deposition of the dummy load have been considered to ensure the safety of the entire ***-power tests have been carried out at a 105 GHz/500 kW ECRH *** results of the tests indicate that the designed dummy load is stable and valid.

关键词： dummy load power measurement quasi-optical method ray tracing ECRH

Machine learning application to predict the electron temperature on the J-TEXT tokamak

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Plasma Science and Technology 2021年第8期23卷 47-52页

作者： Jiaolong DONG Jianchao LI Yonghua DING xiaoqing ZHANG Nengchao WANG Da LI Wei YAN Chengshuo SHEN Ying HE Xiehang REN donghui xia 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 Hubei Key Laboratory of Optical Information and Pattern Recognition Wuhan Institute of TechnologyWuhan 430205People's Republic of China

The reliability of diagnostic systems in tokamak plasma is of great significance for physics researches or fusion *** some diagnostics fail to detect information about the plasma status,such as electron temperature,they can also be obtained by another method:fitted by other diagnostic signals through machine *** paper herein is based on a machine learning method to predict electron temperature,in case the diagnostic systems fail to detect plasma *** fully-connected neural network,utilizing back propagation with two hidden layers,is utilized to estimate plasma electron temperature approximately on the *** input parameters consist of soft x-ray emission intensity,electron density,plasma current,loop voltage,and toroidal magnetic field,while the targets are signals of electron temperature from electron cyclotron emission and x-ray imaging crystal ***,the temperature profile is reconstructed by other diagnostic signals,and the average errors are within 5%.In addition,generalized regression neural network can also achieve this function to estimate the temperature profile with similar *** electron temperature by neural network reveals that machine learning can be used as backup means for plasma information so as to enhance the reliability of diagnostics.

关键词： neural network plasma electron temperature J-TEXT tokamak

Recent progress of the ECRH system and initial experimental results on the J-TEXT tokamak

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Plasma Science and Technology 2022年第12期24卷 127-137页

作者： donghui xia Xixuan CHEN Dengfeng XU Jiangang FANG Junli ZHANG Nengchao WANG Zhoujun YANG Zhongyong CHEN Yonghua DING Wei ZHENG Shaoxiang MA Zhijiang WANG Yuan PAN 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

In order to broaden the range of the plasma parameters and provide experimental conditions for physical research into high-performance plasma,the development of the electron cyclotron resonance heating(ECRH) system for the J-TEXT tokamak was initiated in *** the first stage,the ECRH system operated successfully with one 105 GHz/500 kW/1 s gyrotron in *** than 400 kW electron cyclotron(EC) wave power has been injected into the plasma successfully,raising the core electron temperature to 1.5 *** 2022,another 105 GHz/500 kW/1 s gyrotron completed commissioning tests which signifies that the ECRH system could generate an EC wave power of 1 MW in *** the support of the ECRH system,various physical experiments have been carried out on *** electron thermal transport in ECRH plasmas has been *** ECRH is turned on,the electron thermal diffusivity significantly *** runaway current is elevated when a disruption occurs during ECRH *** the injected EC wave power is 400 kW,the conversion efficiency of runaway current increases from 35% to 75%.Fast electron behavior is observed in electron cyclotron current drive(ECCD) plasma by the fast electron bremsstrahlung diagnostic(FEB).The increase in the FEB intensity implies that ECCD could generate fast electrons.A successful startup with a 200 kW ECW is *** the upgrade of the ECRH system,the J-TEXT operational range could be expanded and further relevant research could be conducted.

关键词： ECRH J-TEXT tokamak electron thermal transport runaway electron current assisted start-up

Investigation of gyrotron-based collective Thomson scattering for fast ion diagnostics in a compact high-field tokamak

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Plasma Science and Technology 2023年第6期25卷 14-22页

作者：徐登峰黄梅陈曦璇张峰夏冬辉王之江潘垣 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 Southwestern Institute of Physics Chengdu 610041People's Republic of China

As a promising method for fast ion diagnostics,collective Thomson scattering(CTS)can measure the one-dimensional velocity distribution of fast ions with high spatial and temporal *** feasibility of diagnosing fast ions in a compact high-field tokamak by CTS was studied in this work,and the results showed that a wide range of probing frequencies could be applied.A high-frequency case and a low-frequency case were mainly considered for fast ion diagnostics in a compact high-field *** use of a high probing frequency could effectively avoid the refraction effect of the beams,while the application of a low probing frequency allows greater flexibility in the selection of scattering angle which may help to improve the spatial *** on typical plasma conditions(B_(0)=12.2 T,n_(e0)=4.3×10^(20)m^(-3),T_(e0)=22.2 keV,T_(i0)=19.8 keV)for a compact high-field tokamak,a220 GHz CTS diagnostic that utilizes a small scattering angle ofθ=30°and a 160 GHz CTS diagnostic that utilizes an orthogonal geometry were *** study showed that the high-frequency case could operate in a wider range of plasma conditions and provide more information on fast ions while the low-frequency case could achieve higher spatial resolution of the poloidal direction.

关键词： fast ion collective Thomson scattering gyrotron

嗜热毛壳菌多糖单加氧酶的氧化特性及协同作用

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菌物学报 2022年第7期41卷 1068-1079页

作者：夏东慧刘宁郭秀娜李多川山东农业大学植物保护学院山东泰安271018

以嗜热毛壳菌Chaetomium thermophilum多糖单加氧酶CtPMO1为研究对象,利用薄层层析色谱法(TLC)、高效液相色谱-示差折光检测法(HPLC-RID)和飞行时间质谱(MALDI-TOF-MS)检测CtPMO1的酶活性,并根据定点突变的原理,将CtPMO1第1位的组氨酸(H... 详细信息

以嗜热毛壳菌Chaetomium thermophilum多糖单加氧酶CtPMO1为研究对象,利用薄层层析色谱法(TLC)、高效液相色谱-示差折光检测法(HPLC-RID)和飞行时间质谱(MALDI-TOF-MS)检测CtPMO1的酶活性,并根据定点突变的原理,将CtPMO1第1位的组氨酸(His1)和第166位的谷氨酰胺(Gln166)突变为H1A、Q166A和Q166E,研究两个突变位点是否参与CtPMO1的氧化作用;另外,采用3,5-二硝基水杨酸(DNS)法检测CtPMO1与纤维素酶(EGⅡ、BGLⅠ和CBHⅠ)的协同效应。研究发现CtPMO1在温度为50℃、pH为5.0的条件下降解磷酸膨胀纤维素(PASC),其酶解产物中不仅存在纤维二糖至纤维五糖,还存在C1氧化寡糖和C4氧化寡糖;此外,发现突变酶H1A完全丧失了酶活,Q166A丧失了C1和C4氧化活性,而Q166E保留了部分C1氧化活性;通过对CtPMO1与纤维素酶协同作用的探究,发现利用CtPMO1预处理磷酸膨胀纤维素(PASC),分别添加EGⅡ、BGLⅠ和CBHⅠ,使还原糖产量分别提高2.10倍、2.08倍和2.16倍,协同度分别是1.022、0.799和0.875。研究结果表明CtPMO1对底物具有C1和C4氧化的功能,其反应的最适温度为50℃、最适pH为5.0;CtPMO1活性中心氨基酸His1和平坦表面氨基酸Gln166均是关键性位点;CtPMO1预处理PASC,使纤维素酶的降解效率发生不同程度的提高。

关键词：多糖单加氧酶纤维素酶 C1/C4位氧化定点突变

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论公安院校大学生的理想和信念

福建公安高等专科学校学报（社会公共安全研究） 2001年第6期15卷 88-90页

作者：夏东辉湖北公安高等专科学校湖北武汉430034

本文全面分析了当前我国公安院校大学生在理想和信念方面存在的七种问题 ,并针对这些问题提出公安院校大学生应该确立四种理想 ,并指出了实现这些理想必须具备的四方面条件。

关键词：公安院校大学生理想信念