速调管走廊抗干扰技术研究

合肥国家同步辐射实验室速调管走廓内存在着高频电磁泄漏，为确保走廓内的通讯信号不被干扰，采用抗干扰技术对泄漏噪声进行了抑制，并对抑制前后的泄漏噪声作了对比测试，结果显示了所采用的抗干扰技术的有效性。     

LaMo阴极材料的制备与对比测试

对ＬａＭｏ阴极材料的制备进行了探索性的尝试,并对从美国购进的ＬａＭｏ阴极材料和自制的ＬａＭｏ材料的发射特性及用于强流离子源的弧放电性能进行了对是度是了较好的实验结果。     

NSRL 200MeV电子直线加速器的速调管真空保护装置

报道了一种能保护高功能速调管安全的速调管真空保护装置。该装置保护动作时间≤１５ｍｓ，在强电磁干扰速调管走廓中能稳定可靠地工作。     

北京谱仪附近空间电磁噪声测量和抑制工作

当北京正负电子对撞机（BEPC）提供的e^ /e^-束流通过北京谱仪（BES）时,在对撞区附近会产生一个空间电磁信号。采用单点测量和矩阵测量等方法,对其进行时域和频域测量及分析。为寻找BES附近的干扰噪声源,提供了非常有益的数据。确认了静电分离器的屏蔽改进效果,并且找到了BES附近另一个干扰噪声源-束流管道上安装DCCT（直流电流传感器）位置附近的陶瓷结构的不连续性而泄漏的电磁波。对其采取了屏蔽、接地等一系列电磁兼容措施,极大地净化了BES附近的空间电磁环境,提高了BES对BEPC束流的利用率,改善了BES数据的可靠性。     

The role of the eigenvalue separation in reactor dynamics and neutron noise theory

The concept of eigenvalue separation (ES) was introduced in the past for the characterisation of the space-time kinetics of reactor transients, and the stability properties of large loosely coupled cores. However, most of the investigations reported so far concern the determination of the ES itself either from static calculations, or from measurements of the flux tilt or neutron noise cross-correlations. Conclusions on system behaviour were only drawn from the properties of the static eigenfunctions, comparing non-perturbed and perturbed systems, without explicitly solving the time- or frequency-dependent problem. In this paper, we explore the role of the ES on the neutronic response of a critical core to small stochastic perturbations (neutron noise); in particular, the spatial and frequency characteristics of the arising neutron noise as a function of the ES, as well as the spatial structure of the perturbation. It is shown that for systems with small ES and non-uniform perturbations, point kinetics will not dominate even for very low frequencies. The results lend some further insight into the origin and properties of the various types of boiling water reactor instabilities.     

电磁脉冲辐照对小鼠受孕率、胚胎发育和子代的影响

电磁辐射的危害、尤其对胚胎发育及子代的影响已引起人们的高度关注[1,2]。本研究对BALB/C雌性小鼠或雄性小鼠进行电磁脉冲照射(场强95.41kVm-1、3×106次和4×106次脉冲),受照雌鼠或雄鼠与未照的雄鼠或雌鼠于照后1天和2月分别交配,用胚胎畸形学的方法分别观察各组雌鼠的受孕率、孕鼠所产的胚胎数及其子代性别比等。经3×106次脉冲的电磁脉冲辐照后的各组,均留一部分孕鼠让其自然分娩,饲养仔鼠,仔鼠成年后采用Y型电迷宫法检测子代小鼠的学习记忆能力,同时将仔代小鼠放置于50℃金属平面上测量其对热伤害感受的反应潜伏期。经3×106次辐照…     

Strategy for solving a coupled problem of the electromagnetic load analysis and design optimization for local conducting structures to support the ITER blanket development

The complexity of the electromagnetic (EM) response of the tokamak structures is one of the key and design-driving issues for the ITER. We consider the specifics of the assessment of ponderomotive forces, acting on local components of a large electro-physical device during electromagnetic transients. A strategy and approach is proposed for the operative EM loads modeling and analysis that enables design optimization at early phases of development. The paper describes a method of principal simplification of the mathematical model, based on the analysis and exploiting specific features and peculiarities of the relevant technical problem, determined by the design and operation of the device and system under consideration. The application of the method for predictive EM loads analysis and corresponding numerical calculations are exemplified for the localized ITER blanket components — shield modules. The example demonstrates the efficiency of EM load analysis in complex electromagnetic systems via a set of simplified models with different scope, contents and level of detail.     

电磁脉冲辐射对小鼠睾丸Occludin表达的影响

探讨电磁脉冲辐射对小鼠睾丸血-睾屏障紧密连接蛋白Occludin表达的变化.采用场强为400 kV/m的辐射场对30只成年雄性Balb/c小鼠进行200次重复全身照射,另30只假照射.于辐照后1、7、14、21和28d分别取小鼠睾丸组织制备石蜡标本或提取组织蛋白和mRNA,使用Real-time PCR、Western...     

A design and characteristic experiment of the small annular linear induction electromagnetic pump

A small-scale annular linear induction electromagnetic pump (ALIP) of the externally-supported-in-pipe type with a flowrate of 60 L/min and a developed pressure of 1.3 bar was developed for the circulation of sodium liquid metal. The developed pressure and the efficiency of the pump were analyzed on the change of the pump-design variables by using an equivalent circuit method. The pump designed was manufactured with the consideration to the material and functional requirements of a chemically-active sodium environment. The silicon–iron steel plates with high magnetic permeability and alumina-dispersion-strengthened-copper bands were used as cores and coils of the pump electromagnet for operating in a high temperature. Each turn of the coil was insulated by an asbestos band to protect against an electrical short at a high temperature. Stainless steel compatible with sodium was selected as a structural material. The completed pump was installed in the sodium experimental loop system. At temperatures of 150 °C and 350 °C, the performance of the ALIP (including the P–Q characteristic) was tested by changing the electrical input. The measurements showed that the pumping flowrate and the developed pressure were increased as the input current, voltage and power increased. On the other hand, the developed pressure was decreased with the increase of the flowrate. At the nominal input current and voltage, the developed pressure was 1.25 bar with the relative error of 3.8% compared with the prediction of 1.3 bar at 150 °C, where the flowrate was 54 L/min. The test on the pump showed good agreement with the theoretical calculation with some experimental errors.     

Effect of electromagnetic coupling on MHD flow in the manifold of fusion liquid metal blanket

In fusion liquid metal (LM) blanket, magnetohydrodynamics (MHD) effects will dominate the flow patterns and the heat transfer characteristics of the liquid metal flow. Manifold is a key component in LM blanket in charge of distributing or collecting the liquid metal coolant. In this region, the complex three dimensional MHD phenomena will be occurred, and the velocity, pressure and flow rate distributions may be dramatically influenced. One important aspect is the electromagnetic coupling effect resulting from an exchange of electric currents between two neighboring fluid domains that can lead to modifications of flow distribution and pressure drop compared to that in electrical separated channels. Understanding the electromagnetic coupling effect in manifold is necessary to optimize the liquid metal blanket design.In this work, a numerical study was carried out to investigate the effect of electromagnetic coupling on MHD flow in a manifold region. The typical manifold geometry in LM blanket was considered, a rectangular supply duct entering a rectangular expansion area, finally feeding into 3 rectangular parallel channels. This paper investigated the effect of electromagnetic coupling on MHD flow in a manifold region. Different electromagnetic coupling modes with different combinations of electrical conductivity of walls were studied numerically. The flow distribution and pressure drop of these modes have been evaluated.     

Calculation of the ex-core neutron noise induced by individual fuel assembly vibrations in two PWR cores

Calculation of the neutron noise induced by fuel assembly vibrations in two pressurized water reactor(PWR) cores has been conducted to investigate the effect of cycle burnup on the properties of the ex-core detector noise. An extension of the method and the computational models of a previous work have been applied to two different PWR cores to examine a hypothesis that fuel assembly vibrations cause the corresponding peak in the auto power spectral density(APSD) increase during the cycle. Stochastic vibrations along a random two-dimensional trajectory of individual fuel assemblies were assumed to occur at different locations in the cores. Two models regarding the displacement amplitude of the vibrating assembly have been considered to determine the noise source. Then, the APSD of the ex-core detector noise was evaluated at three burnup steps. The results show that there is no monotonic tendency of the change in the APSD of ex-core detector; however, the increase in APSD occurs predominantly for peripheral assemblies. When assuming simultaneous vibrations of a number of fuel assemblies uniformly distributed over the core, the effect of the peripheral assemblies dominates the ex-core neutron noise.This behaviour was found similar in both cores.