常凯
,
伍俊
,
蒋坤
,
侍文
,
王会武
,
荣亮亮
,
孔祥燕
,
谢晓明
低温物理学报
基于无人机平台的超导航磁测量安全高效,灵敏度高且信息量丰富,探测优势明显.本文研发了一种基于低温超导的固定翼无人机平台的磁测系统,该系统可实现地磁场的垂直三分量磁场同步测量.系统磁场测量噪声水平0.3 pT/√Hz@1kHz,量程＞60μT,采样率为1024Hz,重15 kg.基于该系统初步开展了室内运动测试,实验结果表明该系统可实现运动平台三轴磁测量,适用于无人机航磁平台.
关键词:
低温SQUID
,
物探应用
,
固定翼无人机
,
动态范围
张勇
,
覃作祥
,
许鸿吉
,
常凯
,
陆兴
,
佟维
中国腐蚀与防护学报
T4003 and Q450NQR1, as well as Nirosta 4003 and Q450NQR1 dissimilar metal joints were welded by ER-309 welding wire. The microstructure oftheir base metal and joint were analyzed by metallographic approach. The corrosion resistance of base metal and joints was evaluated by salt fog and electrochemical corrosion tests. The results demonstrated that as far as the similar metal joints of Nirosta 4003 and T4003 was concerned, the corrosion resistance of welding line was much better than that of base metal. However, the corrosion resistance of heat affected zone (HAZ) became worse. In the case of dissimilar metal joints of Nirosta 4003 and Q450NQR1, as well as T4003 and Q450NQR1, the corrosion resistance of welding line was reduced. Under salt spray condition, the corrosion resistance of welding line and base metal of similar metal joints was comparative. However, the dissimilar metal joints of Nirosta 4003 and Q450NQR1, as well as T4003 and Q450NQR1 exhibited obvious corrosion. Especially, abundant corrosion pits were found near the side of Q450NQR1. Due to the different corrosion voltages of stainless steel, weathering steel, HAZ, and welding line, a series of micro-batteries were formed in the dissimilar metal joints, which worsened the corrosion of weathering steel.
关键词:
铁素体不锈钢
,
weathering steel
,
dissimilar metal joint
,
corrosion resistance
王会武
,
荣亮亮
,
孔祥燕
,
谢晓明
,
徐婷
,
常凯
低温物理学报
瞬变电磁信号具有较宽的频谱,为使得超导瞬变电磁信号的接收不产生失真,要求接收信号的超导传感器具有足够高的带宽(100kHz以上),而接收高带宽信号会导致信号的噪声峰峰值变大,传统的滤波(模拟、数字)方法易造成衰减曲线畸变.基于数据驱动的经验模态分解(Empirical Mode Decomposition,EMD)算法能够根据信号本身特性对其进行信号分解和分量选择,具有自适应和不产生波形畸变的特点.本文采用EMD算法分别对数值模拟和野外实测的超导瞬变电磁信号进行EMD滤波处理和分析,结果表明,EMD可以显著压制瞬变电磁信号衰减曲线中的宽频带噪声且波形无畸变.经过EMD滤波的超导瞬变电磁与原始信号相比,信号衰减时间显著延长(从5ms延长至50ms),表明EMD算法能够极大提高瞬变电磁方法对地下深部信息的探测能力.
关键词:
SQUID
,
瞬变电磁
,
EMD
,
IMF
刘洋
,
荣亮亮
,
蒋坤
,
常凯
,
孔祥燕
,
谢晓明
低温物理学报
超导量子干涉器件(SQUID)是超导磁力仪的核心器件,应用于地球物理探测时,环境射频电磁场干扰SQUID工作,导致性能(噪声和工作稳定性等)全面下降,甚至无法正常工作.本文运用电磁场仿真技术和测试方法,对物探SQUID应用的射频干扰屏蔽方法与效果进行分析研究.模拟户外环境仿真,结果表明:随着屏蔽层数增加可屏蔽的射频场的频谱范围增大,8层时就可达到满意的屏蔽效果.测试与仿真结果的规律一致.基于室内和户外两种不同电磁环境开展了低温SQUID工作射频屏蔽对比验证.实验结果表明:不同应用环境对系统射频屏蔽的要求不同(室内:2层以上屏蔽,户外:8层以上屏蔽).本研究为定量分析并解决物探环境射频屏蔽的关键问题奠定了基础.
关键词:
SQUID
,
物探应用
,
有限元分析
,
射频屏蔽
