永磁除铁装置表面最佳磁感应强度的实验确定方法

在设计永磁除铁装置时,一个关键问题就是吸附表面磁感应强度的确定。在保证吸净率最高的条件下,必须确定其吸附表面磁感应强度大小,以确保除铁装置处于最佳运行状态。本文在大量实验的基础上,给出了测定表面磁感应强度的最佳值方法。

核电站浮子流量计的卡涩机理及应对研究

在核电站项目建设的调试及运营期间,调试及运行人员报告部分金属管浮子流量计在运行时存在卡涩情况。为应对浮子流量计卡涩的问题,基于对浮子流量计测量原理的分析,结合现场故障流量计的拆解情况进行卡涩故障的机制推演,完整分析了浮子流量计卡涩故障的环境工况因素和自身结构条件,并得出卡涩故障是管道内未吹扫干净的铁磁性杂质和浮子流量计运行机制共同作用所致的结论。根据故障机制的各作用环节提出了针对性的解决方案。在此基础上,对浮子流量计厂家提出的解决方案进行了分析,并对后续核电项目选型使用金属管浮子流量计提出了避免卡涩故障的具体应对措施。该研究结果可用于指导核电站流量测量方案的制订,对浮子流量计的设计改进和研发方向有启示作用。

Controlling Thermodynamic Properties of Ferromagnetic Group-Ⅳ Graphene-Like Nanosheets by Dilute Charged Impurity

Using the Kane-Mele Hamiltonian, Dirac theory and self-consistent Born approximation, we investigate the effect of dilute charged impurity on the electronic heat capacity and magnetic susceptibility of two-dimensional ferromagnetic honeycomb structure of group-Ⅳ elements including silicene, germanene and stanene within the Green's function approach. We also find these quantities in the presence of applied external electric field. Our results show that the silicene(stanene) has the maximum(minimum) heat capacity and magnetic susceptibility at uniform electric fields. From the behavior of theses quantities, the band gap has been changed with impurity concentration, impurity scattering strength and electric field. The analysis on the impurity-dependent magnetic susceptibility curves shows a phase transition from ferromagnetic to paramagnetic and antiferromagnetic phases. Interestingly, electronic heat capacity increases(decreases) with impurity concentration in silicene(germanene and stanene) structure.