CARR仪器中子活化分析自动控制系统设计

在中国先进研究堆设计了一套新的仪器中子活化分析自动控制系统。系统主要由辐照管道、样品架、样品转换器、传输装置和3套可同时连续24h工作的HPGe探测器组成。测量盒内装有无线射频识别(RFID)电子标签,对样品进行实时跟踪和定位。压缩空气作为样品传输动力。系统由组态王Kingview6.55、可编程逻辑控制器(PLC)控制,可实现批量样品辐照、冷却、测量等一体化控制。     

Shutdown dose rate benchmark experiment at JET to validate the three-dimensional Advanced-D1S method

The paper describes a new benchmark, performed as a preliminary experiment on JET tokamak during the last shutdown. Dose rate has been measured with different dosimeters along the axis of the main horizontal port of Octant 1, from the plasma centre to 1 m outside the port at various times after shutdown. The activation dose from the horizontal neutron camera, moved outside the torus hall during the shutdown, has also been assessed. The measured values have been compared with dose rates calculated using an Advanced-D1S method in which new computation capabilities have been introduced, such as dose rate spatial mesh map and automated time behaviour.Measurements along the axis of the horizontal port are well predicted by the calculation. With few exceptions, the D1S estimation is within the error of the measurements. The activation of the horizontal camera is underestimated by a factor of 2. However, more accurate measurements are needed to reduce the uncertainties.The Advanced-D1S method, the results and implications of the benchmark are presented and discussed.     

Effects of gamma-ray irradiation on crevice corrosion repassivation potential of stainless steel in high temperature diluted simulated seawater

The crevice corrosion repassivation potentials (E_R,CREV) of type 304 stainless steel (304 SS) were measured in high temperature (373–553 K), diluted simulated seawater under gamma-ray irradiation, in order to confirm the effects of gamma-ray irradiation on the crevice corrosion behavior of a representative stainless steel in seawater. Overall, for high temperatures, the E_R,CREV values decreased with increasing chloride ion concentration, which was the same as the behavior observed under the non-irradiated condition. The E_R,CREV values measured under gamma-ray irradiation were the same or slightly higher than E_R,CREV values measured under the non-irradiated condition when the [Cl^?] was the same. Consequently, it was confirmed that the threshold potential of crevice corrosion of 304 SS for the gamma-ray irradiation of 1.8 kGy at least did not deteriorate compared with the non-irradiated condition. Under the conditions of this work (seawater composition, [Cl^?] range, dose rate, absorbed dose, flow rate, etc.), the crevice corrosion of 304 SS could be suppressed by maintaining the potential below the threshold potential which was determined approximately as ?0.3 V vs. SHE even for the irradiated condition at temperatures up to 553 K.     

Comparison of Methods for Irradiating Prone Patients

The results of irradiation with an 18 MeV rotating gamma-ray setup and three variants of equipment for proton beam transport – horizontal beam, rotating universal GANTRI, and a planar system with irradiation direction limited to ±45° to the horizontal – are compared. The average values of three parameters averaged over the target size and position are obtained for each type of equipment – the fraction of the total dose that strikes the target, the ratio of the average (specific) irradiation dose to healthy tissue to the dose in the target, and the ratio of these quantities. Comparing the results shows that it is desirable to adopt simple planar systems in proton and ion therapy.     

上海光源剂量联锁PLC系统和故障记录

上海光源恒流注入模式需建立辐射剂量硬件联锁。剂量联锁系统以PLC为基础,采用一主站四从站的现场总线布局,通过语句表编程实现逻辑综合,并具有故障记录功能。程序采用字逻辑将状态输入与设定屏蔽位图进行比较,逐个模块地检查有无累积剂量超限输入和瞬时剂量超限输入,综合后经断开延时形成累积剂量联锁输出和瞬时剂量联锁输出。程序通过双字逻辑比较,得到新近发生的故障位置和故障时间,形成故障记录。故障记录功能有助于参与联锁探测器的故障定点诊断和维护。     

Safe disassembly and storage of radioactive components of JT-60U torus

Disassembly of the JT-60U torus was started in 2009 after 18 years of D₂ operations and was completed in October 2012 for assembling the JT-60SA torus at the same position. The JT-60U torus was featured by the complicated and welded structure against the strong electromagnetic force, and by the radioactivation due to deuterium–deuterium (D–D) reactions. Since this work is the first experience of disassembling a large radioactivated fusion device in Japan, careful preparations of disassembly activities, including treatment of the radioactivated materials and safety work, have been made. During the disassembly period over 3 years, careful measures against exposure were taken and stringent control of exposure dose were implemented, and as a result, accumulated collective effective dose of ∼41,000 person-day to workers was only ∼22 mSv in total and no internal exposure was observed. About 13,000 components cut into pieces with measuring the contact dose were removed from the torus hall and stored safely in storage facilities. The total weight of the disassembly components reached up to ∼5400 tonnes. Most of the disassembly components will be treated as non-radioactive ones after the clearance level inspection under the Japanese regulations in the future. The assembly of JT-60SA has started in January 2013 after this disassembly of JT-60U torus.     

InGaAsP多量子阱激光二极管及其组件的γ辐射效应

本工作进行多量子阱激光二极管及其组件的γ辐照实验研究,总剂量（以Si计）达5.5×10⁴Gy。结果表明：多量子阱激光二极管抗γ射线辐照能力很强,在实验总剂量下,裸管形式的多量子阱激光二极管的P-I特性、I-V特性及中心波长基本未变化。而多量子阱激光二极管组件因包含光学窗口、耦合透镜及光纤等附属光学元件,这些附属元件受γ辐照后光学性能下降,最终导致激光二极管组件输出光功率随总剂量增大而下降,停止辐照后,不需加偏置,在室温下即能发生退火,使得斜率效率逐渐回升。     

Spectral Measurement of Atmospheric Pressure Plasma by Means of Digital camera

A digital camera measuring system has been used sucessfully to measure the space fluctuation behaviors of Induced Dielectric Barrier Discharge (IDBD) plasma at atmospheric pressure.The experimental results showed that:(1) The uniformity of elctron Temperature of space depends on discharge condition and structure of web electrode,For a certain web electrode the higher the discharge volgage is ,the more uniform distribution of electron temperature in space will be.For a certain discharge the finer and denser the holes on web electrode are,the more uniform distribution of electron temperature in space will be(2).Digital camera is an available equipment to measure some behaviors of the plasma working at atmospheric pressure.     

一种γ辐照装置安全联锁系统的设计

为了改进一座γ辐照装置的安全性能,使之符合相关标准的要求,设计了一种基于可编程控制器的联锁系统.通过梯形图编程设计实现了顺序巡视、延时、异常报警等功能.结果表明:可编程柔性设计有利于完善系统的安全性.     

Transient Response of GaAs IC's to Ionizing Radiation

Transient responses of GaAs E-JFET planar integrated circuits caused by a 25 ns wide ionizing radiation pulse from a LINAC were measured. Present technology circuits with 2.5 ?m channel length devices have a measured logic upset level of about 1 × 1010 rad(GaAs)/s and a survival dose rate of approximately 1 × 1011 rad(GaAs)/s. A theoretical analysis for logic upset dose rate and a correlation of experimental results with theory is presented. For E-JFET devices with a channel length of 1 ?m, a logic upset dose rate of 1 × 1011 rad(GaAs)/s is predicted.     

64K CMOS随机存储器瞬时辐射损伤模式分析

对64K CMOS随机存储器6264进行了"强光一号"长脉冲辐射状态和短脉冲辐射状态下的辐照实验,测量了存储器翻转效应,分析了不同脉冲宽度下效应的差异,绘制了存储单元的翻转位图,研究了6264的辐射损伤模式。对于6264,其存储单元的翻转主要由内部路轨塌陷引起。     

基于PLC的控制棒驱动机构复验

为了检验控制棒驱动机构的功能和性能是否满足设计规范书的要求,完成驱动机构的出厂试验,设计了控制棒驱动机构试验装置.基于可编程逻辑控制器(以下简称PLC)的控制棒驱动机构试验装置实现了控制棒的提升、保持、下降和报警综合等功能.文中介绍了控制棒驱动机构试验装置的原理和实现方法,通过和驱动机构的联调试验,证明控制棒驱动机构试...     

Relaxation behaviour of radiochemically aged EPDM elastomers

EPDM-type elastomers (70% ethylene; 28% propylene; diene monomer: 2% norbornene) were characterised before and after irradiation using differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). Three formulations were studied: pure elastomer, cross-linked elastomer with dicumyl peroxide and protected with a phenolic-type antioxidant agent. Two irradiation methods were used: γ radiation, under oxygen, at a fixed dose rate of 1 kGy/h, for total integrated doses ranging from 50 to 450 kGy and electron irradiation, under inert atmosphere, at a dose rate of 500 kGy/h, for doses of 100 and 500 kGy. For both types of irradiation, for the three EPDM formulations and for any total integrated dose, DSC and DMA show that a cross-linking phenomenon predominates. Cross-linking increases with the total integrated dose. It is also observed that cross-linking is stronger with the γ irradiation than with the electron irradiation, which confirms the influence of the oxidising atmosphere.     

The Design of High Precision Automatic Dispensing System of Radioactive Liquid

In order to enhance the precision and efficiency of batch preparation equipment used in radioactive sodium iodide ［¹³¹I］ oral solution, a set of high-accuracy automatic dispensing equipment for sodium iodide ［¹³¹I］ oral solution was developed. In this automatic dispensing system, parameters were set through the touch screen and host computer and processed through the core processing programmable logic controller. Operating steps, such as micro-dispensing, diluting , rubber stopper covering and sample pushing, could be controlled step by step. The precision of the automatic dispensing system raised to level of 10^-6 L. This equipment, which were high accuracy, stable performance, good man-machine interface and convenient operation, provided a good technical guarantee for the dispensing of various kinds of radioactive solution.     

Effect of gamma-ray irradiation on the deoxygenation of salt-containing water using hydrazine

In spent fuel pools at the Fukushima Daiichi nuclear power plant, hydrazine was added to salt-containing water in order to reduce dissolved oxygen. Hydrazine is known to reduce dissolved oxygen in high-temperature pure water, but its deoxygenation behavior in salt-containing water at ambient temperature in the presence of radiation is unknown. Deoxygenation using hydrazine in salt-containing water was thus investigated using a ⁶⁰Co gamma-ray source and artificial seawater at room temperature. Water samples containing a small amount of hydrazine were irradiated at dose rates of 100–10,000 Gy/h. The concentration of dissolved oxygen in the water samples was measured before and after irradiation. Notably, a decrease in the dissolved oxygen was only observed after irradiation, and the dissolved oxygen concentration decreased with increasing dose rate and irradiation time. The rate of decrease in the amount of dissolved oxygen using hydrazine was slow in the presence of salts. Kinetic considerations suggested that the deoxygenation of the salt-containing water exposed to gamma-ray irradiation using hydrazine was suppressed by chloride ions.     

基于EPICS的加速器联锁保护系统

介绍一个在EPICS软件环境下实现的用于加速器的联锁保护系统。系统由PowerPC CPU和VxWorks实时操作系统组成的VME前端计算机(IOC)与高性能可编程逻辑控制器PLC—5共同组成。     

离子液体1-丁基-2,3-二甲基咪唑六氟磷酸盐对γ射线辐射稳定性研究

研究了憎水性离子液体1-丁基-2,3-二甲基咪唑六氟磷酸盐([BuMeMeIm]PF6),在氮气保护下,60Coγ射线照射,最大剂量为400 kGy的辐射稳定性。随着辐照剂量的增加,[BuMeMeIm]PF6的颜色逐渐加深,紫外-可见光谱(UV-Vis)中吸光度随辐照剂量的增加呈线性增长,但颜色及吸光度的变化均小于1-丁基-3-甲基咪唑六氟磷酸盐([BuMeIm]PF6)。辐照400 kGy后,[BuMeMeIm]PF6的傅利叶红外光谱(FTIR)和核磁共振氢谱(1H NMR)谱图均未出现变化。高效液相色谱法(HPLC)分析表明辐照400 kGy后,发生辐解的[BuMeMeIm]+的比例约为0.73%,小于同样条件下发生辐解的[BuMeIm]+。电喷雾质谱(ESIMS)结果显示[BuMeMeIm]+中N-butyl键的断裂可能是阳离子分解的重要原因之一。因此,咪唑环C(2)-H被甲基取代,将会增加咪唑阳离子的辐射稳定性,减小阳离子的辐射分解,使得[BuMeMeIm]PF6具有更高的辐射稳定性。     

强辐射环境下CMOS图像传感器噪声对相机分辨率的影响

CMOS图像传感器（CIS, CMOS image sensor）相机是照相装置中常用的成像设备。在核工业环境下的监控过程中,CIS易受γ辐射影响产生噪声,影响图像的成像分辨率,有必要从系统角度评估CIS相机抗辐照能力。通过利用60Co?γ放射源对CIS相机进行辐照实验,分别得到了典型CIS相机的噪声与图像分辨率和辐射剂量的函数关系,进而求出满足相应分辨率条件下CIS相机的辐照剂量上限。研究结果显示,对于相机成像图片目标区域的最小灰度值区域噪声数量占比σ≤2%,CIS相机电离总剂量（total ionizing dose, TID）小于150 krad（Si）,相机分辨率没有明显降低。并且在通过ISO 12233: 2014 eSFR测试相机分辨率中发现,利用基于楔形图获取混淆的开始频率测试法评估辐照相机分辨率参数比SFR测试法更具合理性。     

A distributed control system for picosecond accelerator at SINAP

The picosecond accelerator （PA） is a low energy electron linear accelerator facility under commissioning, which is built for the experiment of ps level pulse radiolysis in Shanghai Institute of Applied Physics （SINAP）. A practical distributed DA＆C system for this facility has been developed. In view of the upgrading-ability and maintainability of the control system and controlled devices, Advantech distributed intelligent DA＆C products are adopted into the control system. ADAM 5000/TCPs with the protocol of Modbus/TCP are employed to accomplish data acquisition and device control. The PC-compatible programmable logic controller, ADAM-5511. is also adopted to handle the interlocks and the emergency events. On the software side, the integrated software package Kingview V6.5, which fi＇iendly supports all Advantech products, has been used to develop the upper layer control logic and process the data. This paper describes the control system design and system architecture, The intelligent ADAM controllers and the software platform are also discussed in detail.     

国产钠冷快堆阻塞计的移动式一体化控制装置的设计

由于工程需求,急需进行钠冷快堆阻塞计的国产化设计,因此针对国产阻塞计设计了其控制系统。通过应用一体化PLC（可编程序控制器）、PID（比例-积分-微分）控制、变频调速和总线通讯等技术,设计了一套移动式一体化控制装置。使用该装置能按照工艺流程实现对工艺设备的一体化控制,并能方便地被移动至钠回路现场,完成阻塞温度的自动测量。