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双语推荐：辐射脉冲

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指数渐变TEM喇叭沿主轴方向长度一定时,主射方向上辐射脉冲峰峰值随口径高度递增,当辐射脉冲峰峰值到达最大值后,辐射脉冲峰峰值随着口径高度递减,并且辐射脉冲波形发生畸变。为了分析响应波形畸变原因,基于等效开路传输线模型给出指数渐变TEM喇叭脉冲响应的近似表达式,并且结合指数渐变TEM喇叭内部的电磁能量流动过程修正辐射脉冲表达式。理论分析表明,指数渐变TEM喇叭辐射脉冲由两个分量叠加而成,并且这分量之间存在的相对时延与高度渐变线的相对变化率正相关,过大的相对时延会使辐射脉冲的波形发生畸变,从而导致辐射脉冲峰峰值小于同尺寸线性渐变TEM喇叭的辐射脉冲峰峰值。利用电磁仿真软件得到相同尺寸的指数渐变TEM喇叭与线性渐变TEM喇叭的辐射脉冲波形,通过二者之间的对比验证理论分析的正确性。
When the main axial length of the exponential tapered TEM horn is constant,the peak-peak value of the radiation pulse increases with the aperture height,after the maximum is reached,the peak-peak value of the radiation pulse decreases with the aperture height and the distortion would occur to the radiation pulse waveform. In order to analyze the causes of the wave-form distortion,an approximate expression of pulse response with exponential tapered TEM horn is given based on the equiva-lent open circuited transmission line model,and the expression is modified by tracing the electromagnetic energy flow in the TEM horn. Theoretical analysis results show that the radiation pulse consists of two components,in which the relative time delay and relative change rate of the transition line have positive correlation. When the relative time delay is too large,the distortion will occur,thus the peak-peak value is lower than that of linear tapered TEM horn with the same size. The wave form of expo-

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在脉冲辐射测量中,为了获取精确的辐射脉冲面积谱需要完整的脉冲信号信息,针对普通数字化多道无法实现直接对辐射探测器输出的脉冲信号进行完整采集,介绍了一种快速准确有效的辐射脉冲信号面积谱获取方法。通过结合高采样高带宽率数字示波器和仪器远程控制、数据采集处理上位机软件,可实现对高计数率、高宽带的脉冲信号实现自动采集,并利用软件批处理的方式实现数据的重建和面积信息获取,最后完成脉冲信号面积谱的自动统计生成,可大大提高辐射脉冲测量工作的效率。
In order to acquire the acreage energy spectrum in activity radiation detection ,the full information of the pulse signal was needed .This paper introduced an available and fast measurement method based on digital oscillograph , because the common MCA system could not straightly disposes the pulse signal from the detector . It achieved the full signals waveforms automatic acquirement with high -sampling and high-bandwidth digital oscilloscope by instrument -control software .At last it statistically traced out the acreage energy spectrum with the information of each pulse signal which was gained by the batch program .It could highly improve the work ef-ficiency of the radiation detection .

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讨论了Z箍缩内爆产生的低频电磁脉冲的辐射特性.Z箍缩驱动金属丝阵或固体套筒高速内爆,部分磁能通过与负载的运动耦合而向外辐射.理论结果表明,电磁脉冲辐射功率由电流和内爆轨迹共同决定.在中国工程物理研究院流体物理研究所的初级实验平台上开展了负载电流为7 MA,10%-90%上升时间65 ns的丝阵Z箍缩实验,根据实验测得的电流和内爆轨迹得到了电磁脉冲的辐射功率和频谱.电磁脉冲峰值功率约为1 GW,能量约为0.5 J,能量转换效率约为10-7；峰值频率位于20-70 MHz,具有较宽的辐射频谱.电磁脉冲辐射参数远小于软X射线辐射参数(峰值功率为50 TW,能量为0.5 MJ).在弱相对论条件下,电磁脉冲辐射功率近似地正比于电流的6次方,随电流急剧增大.软X射线辐射是丝阵Z箍缩过程中的主要能量转换形式,本文的研究结论表明,在更高的驱动电流下,电磁脉冲辐射将提供另一种重要的能量转换途径,势必会对诊断设备造成严重影响；此外,这类强电磁脉冲在其他领域也具有潜在的应用价值.
In this paper, we represent the radiation characteristics of electromagnetic pulse generated by Z pinch implosion. Magnetic energy which couples with motions of metallic wire arrays or solid liners driven by Z pinch can radiate away. Theoretical results indicate that the radiation power of electromagnetic pulse is determined by both load current and implosion trace. Experiments are carried on primary test stand facility at Institute of Fluid Physics where a current rising to 7 MA in (10%-90%) 65 ns is used to drive a wire array Z pinch. The measured load current and implosion trace show that the Z pinch can deliver about 1 GW, 10 ns full width, 20-70 MHz central frequency, broadband electromagnetic pulse with an energy conversion efficiency of 10-7 . Parameters of electromagnetic pulse are much smaller than those of X-ray with a power of 50 TW and an energy of 0.5 MJ. In the approximation of weak relativistic case, the power of electromagnetic pulse which is proportional to sixth power

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针对现有基于TDOA的定位算法难以适应辐射源信号非同步到达的实时定位问题，提出了一种基于TOA预测的非同步照射辐射源定位算法。该算法采用脉冲样本图外推法通过各站接收的短时脉冲列计算TDOA序列（TDOAs），并通过牛顿迭代法实现对辐射源位置的初步估计。对新到达的脉冲采用脉冲样本图外推法进行TOA预测，判别脉冲属性，进而获得新的TDOA测量值，然后采用扩展卡尔曼滤波算法实现对辐射源位置的实时更新。仿真分析表明：该算法解决了非同步照射引起的难以计算 TDOA的问题，并增强了处理的实时性。
As the existing location method based on TDOA cannot adapt to the asynchronous arrival real-time location of emitter signals ,an asynchronous radiation emitter location method based on TOA prediction is proposed .Firstly ,the pulse pattern extrapolating method is adopted to calculate TDOA sequences (TDOAs) through the short-time pulse sequences received by observing platforms ,and the initial estimation of the emitter position is made with Newton iterative algorithm .Then ,the new arri-val pulse attribute is judged by TOA prediction based on the pulse pattern extrapolating method to ob-tain new TDOA values .The extended Kalman filter (EKF) algorithm is used to implement a real-time renewal of the emitter position .Simulation results show that the proposed algorithm can not only o-vercome the difficulty in calculating TDOA that results from asynchronous radiation and but also en-hance the real-time processing .

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脉冲交叠是影响RWR／ESM系统效能的重要因素之一。针对典型四通道比幅测向体制的RWR／ESM系统中因分频段、分象限形成的多通道信号感知结构，采用仿真方式，对多辐射源信号进入RWR／ESM系统后的脉冲交叠情况进行了统计，发现RWR／ESM信道中脉冲交叠的规律：N（N≥2）脉冲交叠比N-1脉冲交叠基本上低一个数量级；且脉冲交叠对不同辐射源信号序列有不同影响，脉冲交叠同时使得后续的脉冲正确配对比率比较低。
Pulses overlapping is one of key factors that affect RWR/ESM system . The multi-sensor channels′characteristic of a typical 4-channel-Amplitude-Comparing DF(Direction Finding)RWR/ESM system is studied in circumstance of multi-radiant objects by simulation and statistics . A law of pulses overlapping inRWR/ESM′s multi-sensor channels is found:the ratio of N+1(N≥2)pulses overlapping is lower in quantita-tively level than that of N pulses overlapping;pulses overlapping effects for different pulse streams are different and make the ratio of pulses right matching smaller .

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为了揭示极低频脉冲电场（extremely low frequency pulsed electric field，ELF-PEF）对作物幼苗抗旱性的影响及其机理，采用渗透势为?0.1MPa的PEG-6000溶液对玉米幼苗形成生理干旱，研究了1Hz脉冲电场对渗透胁迫下玉米幼苗生长和自发光子辐射的变化。结果表明，在?0.1 MPa的渗透胁迫下玉米幼苗根系和叶片鲜质量缓慢增长，玉米幼苗种胚的自发光子辐射表现出先增加后减小的趋势，幼苗根系和叶片的自发光子辐射也呈现出波动性的增长趋势；经过脉冲电场处理的玉米幼苗根系和叶片鲜质量始终高于（P<0.05）未经过脉冲电场处理的对照组，玉米种胚的自发光子辐射峰值出现的时间比对照组早（P<0.01），峰值辐射强度也比对照高（P<0.01），玉米幼苗根系和叶片的自发光子辐射都有所增强（P<0.05），在渗透胁迫初期脉冲电场处理对玉米幼苗叶片自发光子辐射的增强效应非常显著（P<0.01）。研究结果为揭示极低频脉冲电场对作物幼苗抗旱性的影响机理提供参考。
There are many complex physiological and biochemical reactions in the process of crop seed germination, so germinating seeds are very susceptible to environmental changes and have significant changes on the later growth. Using various physical methods to improve crops drought resistance has been one of the important research directions of modern agriculture, and the majority of studies have been focused on the high-voltage electrostatic field. Recent studies showed that the center frequency of corn cell potential fluctuations was in near 1 Hz, the cell potential coupling resonance could be occurred under the action of 1 Hz pulsed electric field, and some key physiological processes such as respiratory metabolism, photosynthesis, stomatal conductance and water uptake could be affected by the extremely low frequency pulsed electric field (ELF-PEF) with 1 Hz. Therefore, the effect of 1 Hz pulsed electric field on crop drought resistance could be greater than the electrostatic fi

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采用原油配制了原油质量分数为5%的油水混合液,通过实验探究了超声辐射功率、辐射时间、间歇比、脉冲重复周期等因素对超声乳化效果的影响.实验结果表明,制备低含油原油乳化液的最佳超声参数为:超声辐射功率400W、辐射时间5min;间歇比和脉冲重复周期对原油乳化效果影响较小.
The influences of ultrasonic radiation power ,irradiation time ,the ratio of intermittent , pulse repetition period and other factors on the ultrasonic emulsifying were studied by preparing 5%crude oil water emulsion .The experimental results showed that the optimum ultrasonic parameters for were as follows :ultrasonic irradiation power 400 W ,ultrasonic irradiation time 5 minutes .Both the intermittent ratio and the pulse repetition period of ultrasonic wave had less impact on the emulsi-fication of mixtures of crude oil .

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针对传统的仅测脉冲到达时间（TOA）定位方法不能适应复杂体制雷达信号的问题，提出了一种新的基于TOA测量的位置信息场定位算法。首先由主站自提取辐射源的脉冲样本图，副站利用主站自提取的脉冲样本图匹配分选出该站接收的辐射源脉冲列，并将其对应的TOA数据传回主站，而后由主站基于各站的TOA测量构造目标位置信息场函数，通过网格搜索法实现对辐射源位置的估计。仿真结果验证了该方法的有效性。
As the traditional location method based on TOA can’t adapt to complex radar signals,a new location method by position information field based on TOA is proposed in this paper. Firstly,the pulse pattern is self-extracted from the pulse train received by the master station,which is used by slave station to sort the emitter’s pulse data,and the TOA of the slave station’pulse data is transformed back to the master station. Then the master station constructs position information field function and obtains the emitter position estimate through grid searching method. Simulation results verify the effectiveness of the algorithm.

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本文讨论了雷电电磁脉冲的危害，包括传导浪涌、辐射电磁场、感应电压，分析雷电电磁脉冲的特性；并以磁屏蔽为主介绍雷电电磁脉冲的防护，以及磁屏蔽材料的选择。
This paper discusses the dangers of lightning electromagnetic pulses, including surges conduction, electromagnetic radiation, and induced voltage. Then it analyzes the characteristics of lightning electromagnetic pulses. Finally, it introduces lightning electromagnetic pulse protection, mainly magnetic shielding, as well as the selection of magnetic shielding material.

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本文介绍了一种环境辐射监测数字伽玛谱仪设计方案。本设计采用Na I(Tl)探测器对伽玛射线进行探测,由FPGA控制可编程增益放大器对核脉冲信号进行调节,以适合后续模数转换输入要求。由FPGA控制高速模数转换器AD9235对核脉冲信号进行模数转换,然后采用海明窗低通FIR数字滤波器对数字核脉冲信号进行滤波,滤除高频噪声。本设计采用TMS320C6713对数字核脉冲信号进行梯形成形,改善弹道亏损和脉冲堆积,最后对其进行幅值判断形成能谱。谱仪经刻度后,不仅可以获得现场辐射计数总量还可以获取现场能谱对核素进行初步判别,这对于工业环境辐射监测非常有意义。本设计具有体积小、设计灵活、可扩展性好等特点,非常适合现场环境辐射监测。
The design of digital gamma -ray spectrometer for environmental radiation monitoring has been pres-ented.It detects gamma ray by NaI(Tl) gamma-ray detector.FPGA plays very import role in logical control and digital low pass FIR filter .FPGA controls programmable gain amplifier ( PGA) to adjust the amplitude of nuclear pulse signal .After high speed ADC acquiring nuclear pulse signal , FPGA filters the digital signal by Hamming window FIR low-pass digital filter .And then DSP ( TMS320 C6713 ) is responsible for digital pulse trapezoidal Shaping , which can reduce pulse pile up and ballistic deficit , peak detecting , and obtaining spec-trum.After calibration, the spectrometer can not only get the total count , but also roughly discriminate nu-clides, which is meaningful to spot radiation monitoring in industrial areas .The design is very smart and scala-ble to meet spot radiation monitoring .

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