一个单采样头的支气管剂量计

提出了一个只有一个采样头的便携式支气管测量计，采样头分别由一层４００目金属筛网和滤膜组成，采样气流面速为１２ｃｍ／ｓ，采样后分别对筛网和滤膜同时测量其总α计数，可得氡子体照射气管支气管（Ｔ－Ｂ区）的年有效剂量（ｍＳｖ／Ａ）如将采样头与主动式活性炭盒串接采样测定氡气浓度，则还可以计算出以μＳｖ／（ａＢｑ．ｍ＾－３）为单位的剂量转换因子，给出了这种支气管剂量计的设计思想和试验性测量结果。     

Measurement of gamma and neutron radiations inside spent fuel assemblies with passive detectors

During operation of a fission nuclear reactor, many radionuclides are generated in fuel by fission and activation of ²³⁵U, ²³⁸U and other nuclides present in the assembly. After removal of a fuel assembly from the core, these radionuclides are sources of different types of radiation. Gamma and neutron radiation emitted from an assembly can be non-destructively detected with different types of detectors. In this paper, a new method of measurement of radiation from a spent fuel assembly is presented. It is based on usage of passive detectors, such as alanine dosimeters for gamma radiation and track detectors for neutron radiation. Measurements are made on the IRT-2M spent fuel assemblies used in the LVR-15 research reactor. During irradiation of detectors, the fuel assembly is located in a water storage pool at a depth of 6 m. Detectors are inserted into central hole of the assembly, irradiated for a defined time interval, and after the detectors removed from the assembly, gamma dose or neutron fluence are evaluated. Measured profiles of gamma dose rate and neutron fluence rate inside of the spent fuel assembly are presented. This measurement can be used to evaluate relative fuel burn-up.     

The sensitivity of 100 nm RADFETs with zero gate bias up to dose of 230 Gy(Si)

The RADFETs (pMOS dosimeters) were irradiated by ionizing radiation from ⁶⁰Co gamma-ray source to dose of 230 Gy(Si) without gate bias, and their reproducibility and sensitivity to radiation were investigated. The completely automatic system containing switching matrix have been used, enabling very reliable measurements of RADFET electrical characteristics. Two sample types from each RADFET chip, with the same gate oxide thickness, but different geometry (channel width and length), were investigated. The samples have shown good reproducibility of the threshold voltage shift during irradiation, i.e., the radiation sensitivity was similar for all samples. Using MG and CP techniques, it has been shown that the slow switching (border) trap density is negligible, but the fixed trap density saturates and the fast switching trap density is linear.     

基于RFID的放射源在线监管系统设计与实现

提出了基于RFID技术的放射源状态实时在线监测的一个解决方案.采用了RFID方式来实时传输放射源的辐射剂量率,对放射源状态及周围环境剂量率进行实时在线监测;同时采用区域无线组网方式建立企业级监控网络,解决了厂区内部远距离布线问题;利用GPRS无线传输将实时数据发送到监控平台或同时发送到政府监管部门.引入随机动态编码每天...     

自显色个人剂量计研究

采用聚合变色体系,以类丁二炔单体PCDA为变色染料,制备了一种用于辐照剂量预警的自显色个人剂量计。对基体材料、稀释剂种类、变色染料、溶解温度、成膜厚度以及膜制备工艺进行了研究,建立了自显色个人剂量计制备方法。剂量计接受0.1～2.5 Gy辐照后,颜色从白色变为蓝色,在681.5 nm处测得剂量响应曲线线性相关系数为0.999 8,照后两周内稳定性良好,可作为预警式个人剂量计使用。     

A CaS:Ce,Sm-based dosimeter for online dosimetry measurement

A film dosimeter based on optically stimulated luminescence (OSL) material of CaS:Ce,Sm was developed for online irradiation dosimetry measurement.The stimulation is provided by a laser with a wavelength of 980 nm,and the OSL luminescenceis collected by a photodiode.Using 60Co γ-rays,we investigated the dosimetry characteristic of the dosimeter at different dose rates and total doses.The real-time detection results showed that the OSL signals versus total ionizing dose exhibited a good linearity in a dose range of 0.1-185 Gy.     

新型金刚石膜辐射剂量计的研究进展

在辐射研究与辐射应用中准确地测量辐射剂量或吸收剂量是一项重要的工作,因此对其所用测试仪器--剂量计的要求也就十分严格.现有的剂量计主要有电离室剂量计和Si二极管剂量计,它们在使用过程中均存在许多不足之处,有必要开发新型的辐射剂量计.近年来,国内外开展了用金刚石膜作为辐射探测材料的研究,并取得了许多进展.简要介绍了该辐射剂量计的原理、研究进展及应用前景.     

基于MSP430单片机的便携式γ个人剂量仪设计与实现

本文设计实现了一台基于MSP430单片机的便携式γ个人辐射剂量仪。系统以MSP430为核心,集成M4011盖革-米勒计数管,PCF8563低功耗高精度时钟芯片;采用2.4寸OLED显示模块实现测量数据和时间的显示;两节3.7V 2300m Ah可充电锂电池为整个系统持续供电并通过直流升压电路为计数管提供正常工作的高压;MSP430内部Flash能将测得数据及对应时间进行实时存储,供后续调用和处理。系统程序设计采用低功耗模式,当信号到来时激活CPU并处理数据。该设计充分利用了MSP430系列单片机的低电压、超低功耗特性,实现了剂量仪的长时间稳定工作,满足个人剂量仪体积小、便于携带、低功耗高精度、实时显示的需求。     

HARSHAW6600系统剂量计算方法分析

HARSHAW6600系统是国内目前应用较广泛的一种热释光剂量测量系统,该系统内部设置了一系列参数用于剂量数据的计算并确保计算的准确性。本文介绍这些参数意义,分析剂量计算的原理,验证计算的准确性,给出低能射线照射时剂量的计算建议。     

Performance of a plastic scintillation fiber dosimeter based on different photoelectric devices

The photoelectric device of a scintillation dosimeter converts photons produced by radiation into an electrical signal.Its features directly determine the overall performance of the dosimeter.For a plastic scintillation fiber dosimeter(PSFD)with a current readout mode,sys-tematic studies of the stability and light-dose response were performed for the photomultiplier tube(PMT),silicon photomultiplier(SiPM),avalanche photodiode(APD),and photodiode(PD).The temperature stability,long-term stability,repeatability,signal-to-noise ratio(SNR),and current dose response of the PSFD with the abovemen-tioned photoelectric devices were studied using a pulsed LED light source and the Small Animal Radiation Therapy platform.An exponential relationship between the dark/net current and temperature was obtained for all the devices.It is shown that the APD is the most sensitive device to temperature,with a current dependence on temperature reaching 6.5％℃-1 at room temperature,whereas for the other devices this dependence is always＜0.6％℃-1.In terms of long-term stability,the net current of PD can change by up to 4％when working continuously for 8 h and 2％when working intermittently for 32 h,whereas for the other devices,the changes are all＜1％.For the dose response,the PMT and SiPM exhibit excellent linear responses and SNRs within the range of 0.1-60 Gy/min.For the PSFD with a current readout mode,the perfor-mance of the PMT and SiPM is concluded to be better than that of the other devices in the study.In particular,the SiPM,which has a compact size,low bias voltage,and antimagnetic interference,has great advantages for further applications.