短語詞組短語Vector -scalar potential 矢量勢electro -magnet vector-potential a 電磁矢勢afour -vector potential [電磁]四元矢量勢Hertz -vector potential 震前電磁場two four -vector potential 雙四維矢勢vortex -vector potential equation 渦量向量勢方程non -dirvergence vector potential 無散矢勢second -order vector potential 二階矢量位 返回 vector-potential