DYS－92型低本底液体闪烁谱仪

Model DYs-92 Low Background Liquid Scintillation Spectrometer

ＤＹｓ－９２型低本底液体闪烁谱仪是ＤＹＳ系列低本底液体闪烁计数器的换代产品。也是为满足测量极低含量的氚和碳－１４环境样品而特殊设计的，该仪器还可测量氪－８５、氯－３６等其它环境放射性同位素以及示踪放射性同位素。ＤＹＳ－９２由主机内的Ｚ８０主板和２８６以上的ＰＣ微机控制运行，采用了新设计的电子学线路，并将线路与主机安装在一起，仅微机在外。软件有：测量运行程序，数据处理程序和能谱分析程序三大部分。在ＤＹＳ－９２中用锗酸铋（ＢＧＯ）晶体作为反符合屏蔽。从用作反符合屏蔽的角度看，它具有体积小且整体重量轻且对γ射线的探测效率高等优点。测量时，正在测量的样品的全部实时信息均显示在微机的显示屏幕上。并能通过人机对话显示出本批样品中已测各样品的能谱以及已测得的各个数据。对于低水平样品来说，往往需要进行长时间的分段测量，这功能是非常有用的。由多道测出的能谱，计算机能自动计算出不同测量道的优值，有利于工作点的选择。特别在样品测量后，如果需要，还能改变测量道。无论用什么方法选择测量道，均能自动地计算出样品水中氚的浓度和碳－１４样品的年代。依据能谱还能判断样品中是否存在发光、相分离和氡。

The model DYS-92 low background liquid scintillation spectrometer as an new innovation is developed.It isspecially designed for measuring extra-low level tritium and ￣(14)C in the environment.Of course,other isotopes,such as ￣(85)Kr,￣(36)Cl in the environment and trace isotopes can also be measured.DYS-92 is controlled by Z80 main plate in the main instrument box and a PC microcomputer of 286 or higher outside the box.New electron-ics has been designed.The software include:operation,data processing and spectrum analysis.The bismuth germanate(BGO)crystal is applied as an anticoincident shielding with higher γefficiency and is lighter and smaller than Nal(T1)crystal.A lot of messages can be observed from the screen of the PC computer during measurement,such as counts of each channel,energy specrum,time,parameters of the measuring process,etc.The statistic data-processing is made in the course of measurement.All of the counts and spectra for any sample can be displayed on the screen by pushing keys.The figure of merit can be calculated from the spectrum by the microcomputer. In particular,the selection of ￣3H,￣(14)C measuring channel can be completed after or before the measurement.In either case,￣(14)C dating of the sample or the calculation of concentration of tritium in water can be fulfilled automatically.(