针对用于高通量中子源的射频四极场(Radio Frequency Quadrupole,RFQ)加速器中交流电流互感器(Alternating Current Current Transformer,ACCT)的脉冲束流测量误差问题,本文提出基于波形解析的标定与校正方法。本文通过分析高脉冲占空...针对用于高通量中子源的射频四极场(Radio Frequency Quadrupole,RFQ)加速器中交流电流互感器(Alternating Current Current Transformer,ACCT)的脉冲束流测量误差问题,本文提出基于波形解析的标定与校正方法。本文通过分析高脉冲占空比工况下ACCT输出信号的基线漂移和脉冲衰减特性,设计了一套集成实时基线跟踪、漂移补偿和脉冲校正的电子学系统。该方法通过动态标定基线漂移量,构建了基于采样点极值的基线计算模型;针对脉冲束流设计线性插值补偿算法,可有效恢复幅度衰减。在西安交通大学加速器中子源装置的2.6 MeV/35 m A质子束流实验中进行验证,结果表明:经校正后2.4 ms脉宽束流的测量误差从4.9%降低至0.2%,使宽脉冲束流测量精度提升显著。该方法为高占空比加速器束诊系统提供了有效的在线校正解决方案。展开更多
Structural and optical properties of nanometric titanium oxide（TixOy） films obtained by cathodic arc plasma deposition were investigated. Phase analysis by x-ray diffraction and Fouriertransform infrared spectroscop...Structural and optical properties of nanometric titanium oxide（TixOy） films obtained by cathodic arc plasma deposition were investigated. Phase analysis by x-ray diffraction and Fouriertransform infrared spectroscopy showed the presence of anatase, rutile, Ti_2O_3, Ti_4O_7 and amorphous phases. Scanning electron microscopy images showed well-developed surface morphology with nano-patterns. Spectroscopic ellipsometry revealed film thicknesses of 53 and50 nm, variable refractive indices dependent on the light wavelength and close to zero extinction coefficients for wavelengths higher than 500 nm. On the basis of ultraviolet–visible spectroscopy data and using the Tauc equation, band gap values for direct and indirect electron transitions were determined.展开更多
Neutral beam injection is one of the effective auxiliary heating methods in magnetic-confinementfusion experiments. In order to acquire the suppressor-grid current signal and avoid the grid being damaged by overheatin...Neutral beam injection is one of the effective auxiliary heating methods in magnetic-confinementfusion experiments. In order to acquire the suppressor-grid current signal and avoid the grid being damaged by overheating, a data acquisition and over-current protection system based on the PXI（PCI e Xtensions for Instrumentation） platform has been developed. The system consists of a current sensor, data acquisition module and over-current protection module. In the data acquisition module,the acquired data of one shot will be transferred in isolation and saved in a data-storage server in a txt file. It can also be recalled using NBWave for future analysis. The over-current protection module contains two modes： remote and local. This gives it the function of setting a threshold voltage remotely and locally, and the forbidden time of over-current protection also can be set by a host PC in remote mode. Experimental results demonstrate that the data acquisition and overcurrent protection system has the advantages of setting forbidden time and isolation transmission.展开更多
文摘针对用于高通量中子源的射频四极场(Radio Frequency Quadrupole,RFQ)加速器中交流电流互感器(Alternating Current Current Transformer,ACCT)的脉冲束流测量误差问题,本文提出基于波形解析的标定与校正方法。本文通过分析高脉冲占空比工况下ACCT输出信号的基线漂移和脉冲衰减特性,设计了一套集成实时基线跟踪、漂移补偿和脉冲校正的电子学系统。该方法通过动态标定基线漂移量,构建了基于采样点极值的基线计算模型;针对脉冲束流设计线性插值补偿算法,可有效恢复幅度衰减。在西安交通大学加速器中子源装置的2.6 MeV/35 m A质子束流实验中进行验证,结果表明:经校正后2.4 ms脉宽束流的测量误差从4.9%降低至0.2%,使宽脉冲束流测量精度提升显著。该方法为高占空比加速器束诊系统提供了有效的在线校正解决方案。
基金by the Ministry of Education,Science and Technological Development of the Republic of Serbia(grant 172026)COST action MP1306
文摘Structural and optical properties of nanometric titanium oxide（TixOy） films obtained by cathodic arc plasma deposition were investigated. Phase analysis by x-ray diffraction and Fouriertransform infrared spectroscopy showed the presence of anatase, rutile, Ti_2O_3, Ti_4O_7 and amorphous phases. Scanning electron microscopy images showed well-developed surface morphology with nano-patterns. Spectroscopic ellipsometry revealed film thicknesses of 53 and50 nm, variable refractive indices dependent on the light wavelength and close to zero extinction coefficients for wavelengths higher than 500 nm. On the basis of ultraviolet–visible spectroscopy data and using the Tauc equation, band gap values for direct and indirect electron transitions were determined.
基金supported by National Natural Science Foundation of China(No.11575240)Key Program of Research and Development of Hefei Science Center,CAS(grant 2016HSC-KPRD002)
文摘Neutral beam injection is one of the effective auxiliary heating methods in magnetic-confinementfusion experiments. In order to acquire the suppressor-grid current signal and avoid the grid being damaged by overheating, a data acquisition and over-current protection system based on the PXI（PCI e Xtensions for Instrumentation） platform has been developed. The system consists of a current sensor, data acquisition module and over-current protection module. In the data acquisition module,the acquired data of one shot will be transferred in isolation and saved in a data-storage server in a txt file. It can also be recalled using NBWave for future analysis. The over-current protection module contains two modes： remote and local. This gives it the function of setting a threshold voltage remotely and locally, and the forbidden time of over-current protection also can be set by a host PC in remote mode. Experimental results demonstrate that the data acquisition and overcurrent protection system has the advantages of setting forbidden time and isolation transmission.
