广东省阳江和台山核电站辐射环境现场监督性监测系统各个监测子站的运行维护

介绍了广东省环境辐射监测中心对阳江核电站和台山核电站辐射环境现场监督性监测系统各个监测子站运行维护情况, 提出监测子站运行维护过程中存在的相关问题, 以及对监测子站升级改造和选址建设的建议。     

Catalyst optimization and reduction condition of continuous growth of carbon nanotubes on carbon fiber surface

Carbon nanotubes (CNTs)/carbon fiber (CF) reinforcements were synthesized under different catalyst compositions and reduction conditions. The effects of the catalyst, reduction temperature and reduction time on the surface morphology, graphitization, and single filament tensile strength of the prepared CNTs/CF samples were investigated. When nickel was used as the catalyst and copper as the catalyst promoter, with the increase of copper concentration, the catalytic activity increased. Thus, the carbon source was consumed more completely, improving the abundance of CNTs with good graphitization. And the effect of repairing CF defects was more obvious, hence the single filament tensile strength accordingly increased. Besides, the increase of catalyst reduction temperature and reduction time intensified the etching of CF by catalyst, and decreased the single filament tensile strength of CF. With the deposition of CNTs, the tensile strength of CF was enhanced in varying degrees. When the concentration of cooper was 0.01 mol/L with the reduction time of 10 min and reduction temperature of 450 °C, CNTs/CF had the highest tensile strength, which can reach up to 4.51 GPa. We determined that bimetallic catalysts could adjust the catalytic activity of nickel. The change of reduction time and temperature would affect the quality of CNTs, which was helpful to obtain high quality CNTs on CF surface and improve the mechanical properties of CNTs/CF and its composites.     

广东省台山核电站运行前(2016/06—2017/12)周围环境气溶胶总α、总β放射性水平监测

报道广东省台山核电站运行前(2016/06—2017/12)周围环境气溶胶中总α、总β放射性水平监测结果。监测结果表明, 台山核电站外围10 km范围内3个监测点(气象站、钦头村、新松水库)环境气溶胶总α放射性水平为0.01～0.57 mBq/m³, 总β为0.07～2.30 mBq/m³。     

2009-2011年和2015-2018年阳江核电站外围 地表水、饮用水的90Sr放射性水平监测

采用国家标准《水和生物样品灰中锶-90的放射化学分析方法》萃取色层法/发烟硝酸沉淀法对阳江核电站运行前后其周围环境地表水、饮用水的⁹⁰Sr放射性水平进行了监测。监测结果表明,阳江核电站运行前后其周围环境地表水、饮用水中⁹⁰Sr活度浓度总体在同一水平,且与对照点⁹⁰Sr放射性水平相当。     

棒磨机振动处理

分析了引起棒磨机振动的现象与原因,认为混凝土基础薄弱是其主要原因,对此采取了基础加固处理与齿隙调整措施。实践证明,经加固处理后对棒磨机的减振和运行发挥了良好的作用。     

Crystallization of amorphous CoSiB alloys: Effect of Fe additions

The results of transmission electron microscopy and X-ray diffraction studies of the crystallization behavior of different CoSiB alloys with and without Fe additions are reported. It is shown that a metastable bcc phase is formed by crystallization in all of the alloys with Fe additions. The bcc phase is not observed in the alloys without Fe additions.     

2014—2017年广东省阳江核电站连续监测γ空气吸收剂量率的质量控制

介绍了广东省阳江核电站2014—2017年连续监测γ空气吸收剂量率的监测设备、运行的质量控制措施, 通过月巡检、仪器比对、放射源测试等措施, 保证了监测结果的准确性。     

A data-driven machine learning approach to predict the hardenability curve of boron steels and assist alloy design

Journal of Materials Science - Boron steel is one of the most valuable lightweight steels for automobile due to its high strength after hot stamping and low cost. In order to ensure service...     

直放站回波消除器中数字抗混频滤波器的设计

就DVB/CMMB数字回波消除直放站研发中涉及的抗混频数字抽取滤波器这一关键技术进行了详细研究,对3种数字抽取滤波器(FIR,HBF,CIC)进行了简要介绍,对其实际性能进行了对比分析。最后,采用Matlab与FPGA硬件平台相结合的设计方法对性能最合适的FIR滤波器进行硬件实现、联合仿真、测试与验证,该设计方法极大优化了设计进程。     

2014—2017年广东省阳江核电站外围γ辐射空气吸收剂量率监测结果

介绍了2014—2017年广东省阳江核电站外围环境γ辐射空气吸收剂量率连续监测结果。结果表明, γ辐射空气吸收剂量率均在本底范围内波动, 未见异常;受气候条件影响, 呈季节性变化;降雨对其影响明显。