一个用于加速器时间分辨分析系统的纳秒高压脉冲装置

设计了一个纳秒高压脉冲装置，脉冲电压可达16kV，前沿上升时间为10ns，此装置已用于加速器时间分析系统，系统的物理分辨时间小于0．8％，时间半高宽为25ns。     

高频高压电子辐照加速器主机室辐射场研究

通过使用MCNP模拟计算和实际测量相结合的方法,对高频高压电子辐照加速器主机室辐射场的主要来源和影响其场强的因素进行了分析。结果表明:主机室的辐射场源项贡献主要来源于辐照室电子打靶后的散射辐射,影响主机室内辐射场强度的因素主要是主机室与辐照室之间管道孔的大小,以及管道孔内屏蔽材料的厚度。     

3.0MeV高频高压电子加速器计算机监控系统的研制

描述了基于PLC的高频高压电子加速器的计算机监控系统。在满足加速器正常操作的基础上,增加了能量反馈控制回路,提高了输出能量的稳定度(1％);保证了扫描电流的大小随输出能量变化的自动跟踪调节：在故障诊断方面也提供了有效的手段帮助排除故障或分析故障原因。     

高压脉冲信号发生器的研制

高压脉冲信号的测量主要通过分压器分流器等测量设备实现。为对分压器或分流器进行校准，研制了高压脉冲信号发生器。研制了低电感的高压开关，其结构简单、性能可靠。     

核电厂高压缸进汽管道高频壳壁振动分析

某核电厂机组启机过程中,对高压缸进汽管道和相连仪表管进行了振动加速度和应变的连续监测。通过振动信号时频分析、机组工况参数分析,发现进汽管道及相连仪表管的振动水平与机组状态及主调节阀的开度显著相关,当电功率达到核功率的53%、主调节阀开度达到13.7%时,管道振动水平明显下降。升速及低功率平台下,进汽管道及仪表管以450 Hz以上高频振动为主。经验公式和有限元计算表明,低功率下高压缸进汽管道可能以壳壁振动为主,并伴随有整体弯曲和扭转振动,且模态频率密集。进汽管道振动加速度高达300 g,长期运行下易导致连接支管的振动疲劳失效。增加约束层阻尼是可能的高频壳壁振动缓解措施。     

“天光Ⅱ—A”强流脉冲加速器的电路模拟

“天光Ⅱ-A”强流脉冲加速器的组成及主要参数如下：Marx发生器由24台美国Maxwell公司生产的100kV／0．1灯低电感脉冲电容器、12个火花隙开关组成,Marx发生器输出电压1．8MV,储能6．75kJ;     

新型双极性高压快脉冲源的基本理论和实验

提出一种新型双极性高压快脉冲源,该脉冲源由两个boost变换器交错并联构成,工作于间断模式((DCM)下.通过对开关器件的寄生电容快速充放电,使输出脉冲具有很快的上升沿:基本恒定的滤波电压对负载放电形成平坦的脉冲顶部.耦合电抗器的能量可以实现开关器件的软导通.分析了该脉冲源的工作原理,并进行了仿真和实验.     

基于功率MOSFET的高速高压脉冲产生器

通过研究功率MOSFET器件的开关特性和脉冲产生技术,设计了互补推挽和集成芯片两种MOSFET栅驱动脉冲电路,其较好的驱动能力,极大的提升了MOSFET的开关速度,分别实现了上升(下降)时间小于5 ns和2.5 ns、输出幅度300~500 V、脉冲宽度5 ns~0.2ms可调的高速、高压的脉冲产生与放大。据此研制成功的脉冲产生器具有稳定性好、带负载能力强、输出脉宽调节范围大、体积小等特点。该脉冲产生器已成功应用于像增强器高速摄影的电子快门装置,并在其他需要高速、高压脉冲领域有一定应用前景。     

一种测量高压气体中离子漂移速度的方法

利用脉冲X射线机作为离子触发源,用高频数字示波器记录负载电阻上的电压信号,通过曲线拟合得出离子在高压气体中的漂移速度。用该方法实测氙离子在1.5 MPa氙气中的漂移速度,结果表明,该方法可简便有效地测量高压气体中的离子漂移速度。     

低抖动纳秒高压脉冲源研究

根据某高能物理实验要求,利用真空平面三极管驱动高压触发管,研制出脉冲幅度达10 kV、前沿小于3.5 ns、抖动低于1 ns,负载电阻R_L为50 Ω时峰值电流可达200 A的高压负脉冲源。本文介绍了该脉冲源的系统组成及工作原理,并给出了系统输出波形。     

双端匹配电路的电容分压器PSPICE分析及应用

详细介绍了具有双端匹配电路电容分压器的基本原理,给出了一种双端匹配电路电容分压器的电路参数,通过PSPICE软件模拟了该分压器的工作过程,并介绍了该电容分压器在TEM小室和有界波电磁脉冲模拟器在监测电场方面的应用.     

The Advantages of Non-Thermal Plasma for Detonation Initiation Compared with Spark Plug

In this paper, the characteristics of detonation combustion ignited by AC-driven non-thermal plasma and spark plug in air/acetylene mixture have been compared in a double-tube experiment system. The two tubes had the same structure, and their closed ends were installed with a plasma generator and a spark plug, respectively. The propagation characteristics of the flame were measured by pressure sensors and ion probes. The experiment results show that, compared with a spark plug, the non-thermal plasma obviously broadened the range of equivalence ratio when the detonation wave could develop successfully, it also heightened the pressure value of detonation wave. Meanwhile, the detonation wave development time and the entire flame propagation time were reduced by half. All of these advantages benefited from the larger ignition volume when a non-thermal plasma was applied.     

卡钳式脉冲电流探测器研究

介绍了一种卡钳式、脉冲电流探测器的研制情况,给出了原理与结构。详细介绍了该探测器的特点和特性参数,同时还给出了探测器的灵敏度、频谱等标定数据以及在实验中的使用情况等。     

Research on the steam–gas pressurizer model with Relap5 code

Steam–gas pressurizers are self-pressurizing, and since steam and noncondensable gas are used to sustain their pressure, they experience very complicated thermal–hydraulic phenomena owing to the presence of the latter. A steam–gas pressurizer model was developed using Relap5 code to investigate such a pressurizer's thermal–hydraulic characteristics.The important thermal–hydraulic processes occurring in the pressurizer model include bulk flashing, rainout, wall condensation with noncondensable gas, and interfacial heat and mass transfer. The pressurizer model was verified using results from insurge experiments performed at the Massachusetts Institute of Technology. It was found that noncondensable gas was one of the important factors governing the pressure response, and the accuracy of the developed model would change with different mass fractions and types of noncondensable gas.     

双脉冲闸流管触发器研制

重氢闸流管开关在高压大电流快脉冲技术领域仍扮演着重要角色,闸流管的触发线路是决定闸流管开关性能的关键因素之一。除提高触发脉冲（G2）的幅度和上升速率外,采用双脉冲触发技术也可有效地改善闸流管开关的时间特性。从通用性、可靠性和可维护性的角度出发,研制了一种集成的全固态双脉冲闸流管触发器,并在BEPCⅡ运行中投入使用。通过测试,闸流管在该触发器的驱动下,时间抖动典型值<1 ns。3年多的运行实践表明,触发器的故障率极低,具有很高的可靠性。     

符合线路断层显像原理及其应用

符合线路断层显像主要由可变角双探头SPECT系统，符合探测线路和衰减校正等组成。对医用核仪器尤其是近年来在国内外刚开始广泛应用的双和／或三探头符合线路断层显像仪的工作原理和特点以及临床应用进行了综述。     

电光显示式火花室吸收谱仪的原理设计和误差分析

本文介绍了电光显示式火花室吸收谱仪的原理设计,并通过对有关物理过程的分析,指出了主要误差的来源及其量级,从而说明了它的可用性。     

热释光油气勘查的机理模型与实验

多年放射性油气勘查工作研究发现,多数油气藏上方存在放射性异常区.但是,油气藏与其上方放射性异常区是否存在必然联系尚无定论.本文就地表砂土热释光勘查油气藏的机理模型,进行了室内微缩模拟实验,试图证明油气迁移可以引起其上方地层中放射性元素的重新分布与富集.实验中排除了环境辐射差异、地下水活动、地形变化、土质不同等带来的干扰,观察到油气藏上方土层中放射性元素重新分布的迹象.结合前期研究工作可以认为,"油气迁移引起上覆地层中放射性元素重新分布"的假设成立,为研究地表热释光油气勘查方法提供了进一步的理论和事实依据.     

A calculation model for breakdown time delay and jitter of gas switches under hundred-nanosecond pulses and its application in a self-triggered pre-ionized switch

In this paper,a calculation model for the breakdown time delay and jitter of gas switches under hundred-nanosecond pulses is proposed and applied in a self-triggered pre-ionized switch.The effects of injection time of pre-ionization,pulse rise time,and the pre-ionization jitter are discussed and verified through experiments.It indicates that the pre-ionization should be injected when the electric field is high enough in the gap,injection after 80％peak-time can ensure its effectiveness.Then the statistical time delay jitter will be determined by the pre-ionization jitter,which is an intrinsic restriction of the self-triggered switch.However,when the changing rate of the pulsed electric field exceeds a certain value,the breakdown time delay jitter can be partly offset in the formative stage because the formative time delay has an exponential relationship with the electric field.Therefore,lower time jitter can be obtained under pulses with a shorter pulse rise time.In general,the results of the calculation model agree with the experimental results,and the experimental parameters which lead to a low jitter can also be used as a reference.     

The features of band structures for woodpile three-dimensional photonic crystals with plasma and function dielectric constituents

The features of the band structures of woodpile three-dimensional (3D) photonic crystals composed of plasma and function dielectric constituents, referred to as function plasma photonic crystals (FPPCs), are theoretically studied by a modified plane wave expansion method, and the formulas for computing the band structures are derived. The arrangement for the proposed FPPCs is that the function dielectric columns are surrounded by plasma, and the embedded dielectric columns are stacked according to the woodpile lattices, which are arrayed with face- centered-tetragonal symmetry. The relative permittivity of function dielectric rods depends on the function coefficient and space coordinates. The relationships between the parameters for inserted function dielectric rods and plasma and the band structures are also investigated. The computed results illustrate that the obtained PBG can be tuned by those parameters as mentioned above. Compared to dielectric–air PCs, function dielectric PCs and plasma dielectric PCs with the same topology, a wider bandwidth of the photonic band gap can be observed in the proposed FPPCs. The calculated results also show us another alternative way to realize reconfigurable applications with 3D FPPCs.