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Development of a high-speed digital pulse signal acquisition and processing system based on MTCA for liquid scintillator neutron detector on EAST
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作者 Yong-Qiang Zhang Li-Qun Hu +4 位作者 Guo-Qiang Zhong Hong-Rui Cao Jin-Long Zhao Li Yang Qiang Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第10期60-72,共13页
In this experimental study, involving deuterium–deuterium fusion neutron emission spectroscopy measurement on the experimental advanced superconducting tokamak(EAST), a liquid scintillator detector(BC501 A) was emplo... In this experimental study, involving deuterium–deuterium fusion neutron emission spectroscopy measurement on the experimental advanced superconducting tokamak(EAST), a liquid scintillator detector(BC501 A) was employed. This decision was based on the detector's superior sensitivity, optimal time-response, and its exceptional n–γ discrimination capability. This detector emits fast pulse signals that are as narrow as 100 ns, with high count rates that can peak at several Mcps. However, conventional nuclear circuits faced challenges in performing pulse height analysis, n–γ pulse shape discrimination, and in recording the entire pulse waveform under such high count rate conditions. To address these challenges, a high-speed digital pulse signal acquisition and processing system was designed. The system was developed around a micro-telecommunications computing architecture. Within this structure, a signal acquisition and processing(SAQP) module communicated through PCI Express links, achieving a bandwidth of up to 1.6 GB/s. To accurately capture the detailed shape of the pulses, four channels of analog-to-digital converters were used, each with a 500-MSPS sampling rate and a 14-bit resolution, ensuring an accuracy that surpassed 11 bits. An n–γ discrimination algorithm, based on the two-gate integral method, was also developed. Implemented within field programmable gate arrays, this algorithm provided a real-time n–γ discrimination spectrum for pulse height analysis. The system underwent rigorous testing in a laboratory setting and during an EAST experiment. The results confirmed that the innovative SAQP system can satisfy the demanding requirements of high-parameter experiments, manage count rates of up to 2 Mcps, execute real-time n–γ discrimination algorithms, and record entire pulse waveforms without any data loss. 展开更多
关键词 EAST NES high-speed MTCA n–γdiscrimination Entire pulse waveform
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Near-fault directivity pulse-like ground motion effect on high-speed railway bridge 被引量:8
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作者 陈令坤 张楠 +3 位作者 蒋丽忠 曾志平 陈格威 国巍 《Journal of Central South University》 SCIE EI CAS 2014年第6期2425-2436,共12页
The vehicle-track-bridge(VTB)element was used to investigate how a high-speed railway bridge reacted when it was subjected to near-fault directivity pulse-like ground motions.Based on the PEER NAG Strong Ground Motion... The vehicle-track-bridge(VTB)element was used to investigate how a high-speed railway bridge reacted when it was subjected to near-fault directivity pulse-like ground motions.Based on the PEER NAG Strong Ground Motion Database,the spatial analysis model of a vehicle-bridge system was developed,the VTB element was derived to simulate the interaction of train and bridge,and the elasto-plastic seismic responses of the bridge were calculated.The calculation results show that girder and pier top displacement,and bending moment of the pier base increase subjected to near-fault directivity pulse-like ground motion compared to far-field earthquakes,and the greater deformation responses in near-fault shaking are associated with fewer reversed cycles of loading.The hysteretic characteristics of the pier subjected to a near-fault directivity pulse-like earthquake should be explicitly expressed as the bending moment-rotation relationship of the pier base,which is characterized by the centrally strengthened hysteretic cycles at some point of the loading time-history curve.The results show that there is an amplification of the vertical deflection in the girder's mid-span owing to the high vertical ground motion.In light of these findings,the effect of the vertical ground motion should be used to adjust the unconservative amplification constant 2/3 of the vertical-to-horizontal peak ground motion ratio in the seismic design of bridge. 展开更多
关键词 ELEMENT near-fault ground motion directivity pulse high-speed railway bridge earthquake response
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Analysis of droplet transfer of pulsed MIG welding based on electrical signal and high-speed photography 被引量:1
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作者 姚屏 薛家祥 +1 位作者 黄文超 张瑞 《China Welding》 EI CAS 2009年第1期67-72,共6页
In order to study how welding parameters affect welding quality and droplet transfer, a synchronous acquisition and analysis system is established to acquire and analyze electrical signal and instantaneous images of d... In order to study how welding parameters affect welding quality and droplet transfer, a synchronous acquisition and analysis system is established to acquire and analyze electrical signal and instantaneous images of droplet transfer simultaneously, which is based on a self-developed soft-switching inverter. On the one hand, welding current and voltage signals are acquired and analyzed by a self-developed dynamic wavelet analyzer. On the other hand, images are filtered and optimized after they are captured by high-speed camera. The results show that instantaneous waveforms and statistical data of electrical signal contribute to make an overall assessment of welding quality, and that optimized high-speed images allow a visual and clear observation of droplet transfer process. The analysis of both waveforms and images leads to a further research on droplet transfer mechanism and provides a basis for precise control of droplet transfer. 展开更多
关键词 pulsed MIG welding droplet transfer high-speed photography image processing wavelet analysis
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Artificial neural network algorithm for pulse shape discrimination in 2πα and 2πβ particle surface emission rate measurements
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作者 Yuan-Qiao Li Bao-Ji Zhu +4 位作者 Yang Lv Heng Zhu Min Lin Ke-Sheng Chen Li-Jun Xu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第10期91-102,共12页
To enhance the accuracy of 2πα and 2πβ particle surface emission rate measurements and address the identification issues of nuclides in conventional methods, this study introduces two artificial neural network(ANN... To enhance the accuracy of 2πα and 2πβ particle surface emission rate measurements and address the identification issues of nuclides in conventional methods, this study introduces two artificial neural network(ANN) algorithms: back-propagation(BP) and genetic algorithm-based back-propagation(GA-BP). These algorithms classify pulse signals from distinct α and β particles. Their discrimination efficacy is assessed by simulating standard pulse signals and those produced by contaminated sources, mixing α and β particles within the detector. This study initially showcases energy spectrum measurement outcomes, subsequently tests the ANNs on the measurement and validation datasets, and contrasts the pulse shape discrimination efficacy of both algorithms. Experimental findings reveal that the proportional counter's energy resolution is not ideal, thus rendering energy analysis insufficient for distinguishing between 2πα and 2πβ particles. The BP neural network realizes approximately 99% accuracy for 2πα particles and approximately 95% for 2πβ particles, thus surpassing the GA-BP's performance. Additionally, the results suggest enhancing β particle discrimination accuracy by increasing the digital acquisition card's threshold lower limit. This study offers an advanced solution for the 2πα and 2πβ surface emission rate measurement method, presenting superior adaptability and scalability over conventional techniques. 展开更多
关键词 pulse shape discrimination Artificial neural networks Alpha and beta sources Multi-wire proportional counter Surface emission rate
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Isolated attosecond pulse generation with few-cycle two-color counter-rotating circularly polarized laser pulses 被引量:1
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作者 吴劲松 贾正茂 曾志男 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期160-163,共4页
Most of the schemes for generating isolated attosecond pulses(IAP) are sensitive to the carrier-envelope phase(CEP)of the driving lasers. We propose a scheme for generating IAP using two-color counter-rotating cir... Most of the schemes for generating isolated attosecond pulses(IAP) are sensitive to the carrier-envelope phase(CEP)of the driving lasers. We propose a scheme for generating IAP using two-color counter-rotating circularly polarized(TCCRCP) laser pulses. The results demonstrate that the dependence of the IAP generation on CEP stability is largely reduced in this scheme. IAP can be generated at most of CEPs. Therefore, the experiment requirements become lower. 展开更多
关键词 isolated attosecond pulse carrier-envelope phase two-color counter-rotating circularly polarized laser fields high-order harmonic generation
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High-Speed,Robust CMOS Dynamic Circuit Design
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作者 赖练章 汤庭鳌 林殷茵 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第6期1006-1011,共6页
A novel circuit with a narrow pulse driving structure is proposed for enhancing the noise immunity and improving the performance of wide fan-in dynamic circuits. Also,an analytical mode that agrees well with simulatio... A novel circuit with a narrow pulse driving structure is proposed for enhancing the noise immunity and improving the performance of wide fan-in dynamic circuits. Also,an analytical mode that agrees well with simulations is presented for transistor sizing. Simulation results show that an improvement of up to 12% over the conventional technique at 1GHz is obtained with this circuit,which can run 1.6 times faster than the existing technique with the same noise immunity. 展开更多
关键词 domino circuit noise immunity high-speed KEEPER narrow pulse
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Electric characteristic and cavitation bubble dynamics using underwater pulsed discharge 被引量:2
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作者 Minglei SHAN Bingyan CHEN +3 位作者 Cheng YAO Qingbang HAN Changping ZHU Yu YANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第7期16-22,共7页
Underwater pulsed discharge is widely applied in medicine, machining, and material modification.The induced cavitation bubble and subsequent cavitation collapse are considered the major motivations behind these applic... Underwater pulsed discharge is widely applied in medicine, machining, and material modification.The induced cavitation bubble and subsequent cavitation collapse are considered the major motivations behind these applications. This paper presents an underwater pulsed discharge system.The experimental setup is established to induce and investigate the cavitation bubble assisted with a high-speed camera. Three aspects, including the characteristic of the discharge with different applied voltages and conductivities, the evolution of the cavitation bubble profile, and the energy efficiency of cavitation bubble inducing, are investigated, respectively. Especially, the mechanism of pre-discharge time delay in the low field intensity case is explained using the Joule heat effect.The results show the validity of the underwater pulsed discharger and experimental setup. The present underwater pulsed discharger is proved to be a simple, portable, and easy-to-implement device for the investigation of cavitation bubble dynamics. 展开更多
关键词 UNDERWATER pulsed DISCHARGE CAVITATION BUBBLE ELECTRIC DISCHARGE CHARACTERISTIC high-speed camera
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ECCM schemes in netted radar system based ontemporal pulse diversity 被引量:1
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作者 ahmed abdalla zhao yuan bin tang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第5期1001-1009,共9页
For a netted radar system to counteract the deceptionelectronic countermeasure (ECM) signals, an effective electroniccounter countermeasure (ECCM) approach is proposed. The proposedapproach is realized based on th... For a netted radar system to counteract the deceptionelectronic countermeasure (ECM) signals, an effective electroniccounter countermeasure (ECCM) approach is proposed. The proposedapproach is realized based on the new signaling strategyfor the temporal pulse diversity, which makes use of transmittingpulses at each pulse repetition interval (PRI) with specific transmissionpulse block, and then following proper processing andinformation fusion. The existence of the deceptive ECM signal isconfirmed by one station, while the other stations in the nettedradar with same parameters applied the pulse diversity skillfully.Meanwhile, this method ensured that, pulse diversity can be appliedin netted radar. The performance assessment shows that theproposed solutions are effective in presence of ECM signals. Thisalgorithm has been demonstrated by simulations. The presentedsimulation results are in excellent consensus with theoretical predictions. 展开更多
关键词 pulse diversity electronic counter countermeasure(ECCM) digital radio frequency memory (DRFM) electronic countermeasure(ECM) netted radar matching filter.
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Dynamic simulation and safety evaluation of high-speed trains meeting in open air 被引量:3
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作者 Songyan Li Zhijun Zheng +1 位作者 Jilin Yu Chunqiang Qian 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第2期206-214,共9页
Dynamic responses of a carriage under excitation with the German high-speed low-interference track spectrum together with the air pressure pulse generated as high-speed trains passing each other are investigated with ... Dynamic responses of a carriage under excitation with the German high-speed low-interference track spectrum together with the air pressure pulse generated as high-speed trains passing each other are investigated with a multi-body dynamics method.The variations of degrees of freedom(DOFs:horizontal movement,roll angle,and yaw angle),the lateral wheel-rail force,the derailment coefficient and the rate of wheel load reduction with time when two carriages meet in open air are obtained and compared with the results of a single train travelling at specifie speeds.Results show that the rate of wheel load reduction increases with the increase of train speed and meets some safety standard at a certain speed,but exceeding the value of the rate of wheel load reduction does not necessarily mean derailment.The evaluation standard of the rate of wheel load reduction is somewhat conservative and may be loosened.The pressure pulse has significan effects on the train DOFs,and the evaluations of these safety indexes are strongly suggested in practice.The pressure pulse has a limited effect on the derailment coefficien and the lateral wheel-rail force,and,thus,their further evaluations may be not necessary. 展开更多
关键词 high-speed train Pressure pulse Derailment Dynamics simulation Safety standard
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Experimental investigation on the plasma morphology of ablative pulsed plasma thruster with tongue-shaped and flared electrodes
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作者 Jianjun WU Yu ZHANG +1 位作者 Yang OU Hua ZHANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第9期51-58,共8页
Ablative pulsed plasma thrusters(APPTs)are considered as an attractive propulsion option for station-keeping and drag makeup purposes for mass-and power-limited satellites.In order to understand the physical mechanism... Ablative pulsed plasma thrusters(APPTs)are considered as an attractive propulsion option for station-keeping and drag makeup purposes for mass-and power-limited satellites.In order to understand the physical mechanism of APPTs,high-speed camera and optical emission spectroscopy are utilized to investigate the plasma characteristics including the spatial distribution and composition between the electrodes.The plume images and spectra at different times and positions are experimentally recorded,and the spatial distribution,composition,and trajectory of plasmas can be concluded through analyzing them.With the increase of the distance from the ablation surface,two clusters of plasmas near the anode and cathode meet downstream,and the species and density of plasmas tend to be uniform. 展开更多
关键词 pulsed plasma thruster high-speed camera optical emission spectrum plume distribution
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Characteristic analysis of air pressure wave generated by high-speed trains traveling through a tunnel
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作者 Chuanhui WU Xiangling GAO Pinxian GAO 《Journal of Modern Transportation》 2012年第1期31-35,共5页
It is a complicated dynamic phenomenon when a transient pressure pulse is triggered by two high-speed trains passing each other in a tunnel. The air pressure pulse is a transient excitation to side wall of the car bod... It is a complicated dynamic phenomenon when a transient pressure pulse is triggered by two high-speed trains passing each other in a tunnel. The air pressure pulse is a transient excitation to side wall of the car body. It can stimulate almost all vibration modes of the car body and the correlated assemblies, cause serious aerodynamic noise, and have important impacts on car body distortion, train noise, and operation safety. This article analyzes the time- frequency characteristics and main parameters of field-measured the air pressure wave, and its relationship with the train velocity as well as the vibration of the car body. Cepstrum analysis concludes that in the process of the meeting, the air pressure wave in tunnel crossing is a multiplying pressure wave instead of a superposed wave. The pressure pulse during the meeting is non-symmetrical one featured with a sharp front, large amplitude, fluctuating central sec- tion, and less sharp tail. The pulse width is inversely proportional to the train speed. As the speed increases, the impulse amplitude is amplified, and the speed of pulse front is advanced. 展开更多
关键词 high-speed train air pressure pulse transient excitation modes of vibration
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Design of control sequence of pulses for the population transfer of high dimensional spin 1/2 quantum systems
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作者 Cong Shuang Lou Yuesheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第6期1226-1234,共9页
On the basis of the relationship between the Hamiltonian of spin 1/2 quantum system under control and the energy level structure and transitions, a radio frequency pulse sequence is designed using intuitive and half c... On the basis of the relationship between the Hamiltonian of spin 1/2 quantum system under control and the energy level structure and transitions, a radio frequency pulse sequence is designed using intuitive and half counter-intuitive sequences of pulse to transfer the population of the 3-qubit system coherently. The effectiveness of the designed control sequence is verified through the system simulation experiment of the evolution of state. In principle, the design method of the control pulse sequence proposed can be generalized to use in the quantum systems of higher dimension. 展开更多
关键词 quantum system control population transfer pulse sequence design intuitive sequence half counter-intuitive sequence
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LPI雷达信号调制识别及参数估计研究进展
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作者 王海英 张群英 +2 位作者 成文海 董家铭 刘小军 《系统工程与电子技术》 EI CSCD 北大核心 2024年第6期1908-1924,共17页
低截获概率(low probability of intercept,LPI)雷达已成为新时代雷达装备中关键的技术体制或工作模式,针对LPI雷达信号调制识别及参数估计方法的研究是当前雷达对抗侦察领域的热点。首先,分析了几种典型LPI雷达信号的脉内特征,梳理了LP... 低截获概率(low probability of intercept,LPI)雷达已成为新时代雷达装备中关键的技术体制或工作模式,针对LPI雷达信号调制识别及参数估计方法的研究是当前雷达对抗侦察领域的热点。首先,分析了几种典型LPI雷达信号的脉内特征,梳理了LPI雷达信号调制识别及参数估计的传统和主流方法,并说明其原理、优缺点和研究现状。最后,总结了现有LPI雷达信号调制识别及参数估计方法尚存的问题,并指出其未来发展趋势,旨在为今后的研究提供参考。 展开更多
关键词 雷达对抗侦察 低截获概率雷达信号 脉内特征 调制识别 参数估计
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非均匀间歇采样转发干扰对脉内捷变雷达影响分析
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作者 孙宗正 刘智星 +2 位作者 肖国尧 齐晗廷 全英汇 《系统工程与电子技术》 EI CSCD 北大核心 2024年第5期1544-1554,共11页
脉内频率捷变雷达通过自身“主动”抗干扰特性,利用传统间歇采样转发干扰的不连续性和周期性的特点,结合抗干扰算法,可以有效抑制间歇采样转发干扰。为提高干扰机对脉内频率捷变雷达的干扰效能,本文提出采用非均匀间歇采样转发干扰对脉... 脉内频率捷变雷达通过自身“主动”抗干扰特性,利用传统间歇采样转发干扰的不连续性和周期性的特点,结合抗干扰算法,可以有效抑制间歇采样转发干扰。为提高干扰机对脉内频率捷变雷达的干扰效能,本文提出采用非均匀间歇采样转发干扰对脉内频率捷变雷达进行干扰,首先对截获到的脉内频率捷变雷达信号通过时频脊线提取与小波变换进行参数估计,获取子脉冲宽度,然后根据子脉冲宽度约束干扰参数,构造非均匀间歇采样转发干扰。理论分析和结果表明,通过非均匀间歇采样转发使得脉内频率捷变雷达在时频域等多域难以抑制干扰,极大地提升了干扰机的干扰能力。 展开更多
关键词 电子对抗 脉内频率捷变 时频脊线 小波变换 非均匀间歇采样转发干扰 干扰参数
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Motion detection for high-speed high-brightness objects based on a pulse array image sensor
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作者 Peiwen ZHANG Jiangtao XU +2 位作者 Huafeng NIE Zhiyuan GAO Kaiming NIE 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2022年第1期113-122,共10页
We describe a method of optical flow extraction for high-speed high-brightness targets based on a pulse array image sensor(PAIS).PAIS is a retina-like image sensor with pixels triggered by light;it can convert light i... We describe a method of optical flow extraction for high-speed high-brightness targets based on a pulse array image sensor(PAIS).PAIS is a retina-like image sensor with pixels triggered by light;it can convert light into a series of pulse intervals.This method can obtain optical flow from pulse data directly by accumulating continuous pulses.The triggered points can be used to filter redundant data when the target is brighter than the background.The method takes full advantage of the rapid response of PAIS to high-brightness targets.We applied this method to extract the optical flow of high-speed turntables with different background brightness,with the sensor model and actual data,respectively.Under the sampling condition of 2×10^(4) frames/s,the optical flow could be extracted from a high-speed turntable rotating at 1000 r/min.More than 90%of redundant points could be filtered by our method.Experimental results showed that the optical flow extraction algorithm based on pulse data can extract the optical flow information of high-brightness objects efficiently without the need to reconstruct images. 展开更多
关键词 Optical flow Retina-like image sensor pulse triggered high-speed targets Vision processing
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双束对射激光驱动超薄靶的超短脉冲中子源
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作者 冯凯源 邵福球 +7 位作者 蒋祥瑞 邹德滨 胡理想 张国博 杨晓虎 银燕 马燕云 余同普 《物理学报》 SCIE EI CAS CSCD 北大核心 2023年第18期118-128,共11页
使用粒子模拟程序和蒙特卡罗方法研究了双束对射圆极化激光与超薄氘靶相互作用中氘氘聚变反应产生中子的过程.研究发现,由于净光压和横向不稳定性发展的差异,激光电场矢量旋转方向和初始相对相位差对氘靶压缩及中子特性有重要影响.选择... 使用粒子模拟程序和蒙特卡罗方法研究了双束对射圆极化激光与超薄氘靶相互作用中氘氘聚变反应产生中子的过程.研究发现,由于净光压和横向不稳定性发展的差异,激光电场矢量旋转方向和初始相对相位差对氘靶压缩及中子特性有重要影响.选择相对相位差为0且电场矢量旋转方向相同的双束光,可获得最高的中子产额;而采用相对相位差为0.5π或1.5π且电场矢量旋转方向不同的对射光,中子具有定向的空间分布.对于强度为1.23×10^(21)W/cm^(2)、脉宽为33 fs、相对相位差为0.5π的左旋光和右旋光,可获得产额为8.5×10^(4)n、强度为1.2×10^(19)n/s、脉宽为23 fs、前冲性较好且分布可调谐的脉冲中子源. 展开更多
关键词 双束对射圆极化激光 相对相位差 电场矢量旋转方向 脉冲中子源
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采用多像素光子计数器的单光子探测模块设计
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作者 杨延丽 郑新旺 杨光松 《集美大学学报(自然科学版)》 CAS 2023年第2期185-192,共8页
为了在化学发光仪器中替代传统的光电倍增管(PMT),克服PMT体积大、探测效率低、需要上千伏偏置电压的缺点,设计了一种多像素光子计数器(MPPC)的单光子探测模块。在对前置放大器电路进行理论分析和仿真的基础上,设计了放大电路、MPPC偏... 为了在化学发光仪器中替代传统的光电倍增管(PMT),克服PMT体积大、探测效率低、需要上千伏偏置电压的缺点,设计了一种多像素光子计数器(MPPC)的单光子探测模块。在对前置放大器电路进行理论分析和仿真的基础上,设计了放大电路、MPPC偏置电路和制冷电路;利用高速比较器进行脉冲信号鉴别,滤除噪声和干扰;采用软件校正的办法处理脉冲堆积,进一步提高了计数准确性。测试结果表明,该模块的变异系数、线性相关系数、重复性等指标均优于传统的PMT探测器,能有效地应用于单光子计数检测分析仪器。 展开更多
关键词 多像素光子计数器 化学发光 放大电路 脉冲堆积
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罗氏线圈电子式电流互感器积分特性研究 被引量:20
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作者 刘志恒 段雄英 +2 位作者 廖敏夫 邹积岩 张文娜 《电力自动化设备》 EI CSCD 北大核心 2017年第3期191-196,共6页
为降低电子式电流互感器(ECT)的暂态误差、提高稳态电流的测量准确度,提出了一种应用于罗氏线圈ECT信号采集系统的压频变换器模数混合积分器(VFC-ADI)方法。对罗氏线圈输出信号进行压频数值转换,由脉冲计数器完成数值计数,微处理器对计... 为降低电子式电流互感器(ECT)的暂态误差、提高稳态电流的测量准确度,提出了一种应用于罗氏线圈ECT信号采集系统的压频变换器模数混合积分器(VFC-ADI)方法。对罗氏线圈输出信号进行压频数值转换,由脉冲计数器完成数值计数,微处理器对计数值处理后得出被测电流的积分波形。选取VFC芯片AD7742进行仿真分析,仿真结果显示VFC-ADI方法能准确地反映一次侧暂态电流波形。对罗氏线圈ECT暂态故障电流及稳态电流进行试验测试,结果表明VFC-ADI方法能准确反映暂态故障电流特征;对于稳态电流测试,比差的变化范围为-0.15%~0.15%,角差的变化范围为-1′~1.5′,其输出值完全满足0.2 s级基本准确度测试要求。VFC-ADI方法在模数转换过程中实现了积分功能,数据处理结果表明其更接近于理想积分器。 展开更多
关键词 罗氏线圈 电子式电流互感器 VFC 脉冲计数器 模数混合积分器 误差
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条斑紫菜蛋白和多糖的逆流脉冲超声辅助提取技术研究 被引量:9
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作者 王婷 马海乐 +2 位作者 曲文娟 吕艳歌 郑惠华 《食品工业科技》 CAS CSCD 北大核心 2012年第13期228-230,235,共4页
为了缩短生产周期和提高产品产量,本文采用逆流脉冲超声技术对条斑紫菜中蛋白和多糖进行提取。采用Box-Behnken中心组合设计方法结合响应面分析对脉冲超声辅助提取条件进行优化。研究得到了提取的回归方程,通过回归分析与实验验证。在... 为了缩短生产周期和提高产品产量,本文采用逆流脉冲超声技术对条斑紫菜中蛋白和多糖进行提取。采用Box-Behnken中心组合设计方法结合响应面分析对脉冲超声辅助提取条件进行优化。研究得到了提取的回归方程,通过回归分析与实验验证。在提取液pH9.0、脉冲超声的工作时间4s和间歇时间2s的条件下,获得紫菜蛋白和多糖逆流脉冲超声辅助提取的最佳工艺条件为:提取时间85min、料液温度40℃、料液比19:1(mg/mL),在此最佳条件下,紫菜蛋白和多糖总得率高达37.26%,其中紫菜蛋白和多糖的得率分别为15.68%和21.58%。通过与传统的浸提法对照实验,发现利用逆流脉冲超声辅助提取紫菜中蛋白和多糖的总得率提高了116.38%,提高幅度显著。 展开更多
关键词 条斑紫菜 逆流脉冲超声辅助提取 蛋白 多糖 响应面分析
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新型大功率电磁脉冲形成与发射技术研究 被引量:3
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作者 周霖 宋耀良 +1 位作者 谢中元 浩明 《兵工学报》 EI CAS CSCD 北大核心 2009年第12期1743-1747,共5页
高功率电磁脉冲是地球物理研究、地质勘探、石油开采以及电子对抗和微波武器等军事领域极具潜在应用价值的技术。在讨论传统脉冲磁流体动力(MHD)系统和现代脉冲MHD的基础上,探讨了基于火药燃烧的大功率脉冲形成与发射技术,着重研究了低... 高功率电磁脉冲是地球物理研究、地质勘探、石油开采以及电子对抗和微波武器等军事领域极具潜在应用价值的技术。在讨论传统脉冲磁流体动力(MHD)系统和现代脉冲MHD的基础上,探讨了基于火药燃烧的大功率脉冲形成与发射技术,着重研究了低压单脉冲MHD输出转换为大功率多脉冲电磁能的方法和实现电路,给出了实验结果,并对实现该系统的一些关键问题进行了阐述。 展开更多
关键词 电磁学 脉冲磁流体发电 脉冲形成 电子对抗
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