Light 0- Meson Solution of Bethe-Salpeter Equation Involving the Vacuum Condensates in QCD

We dkcuss the Bethe-Salpeter equation involving the vacuum condensates in QCD in the backgrouud fields. The bound state equation for the light 0^- meson (π and K) is solved in the ladder approximation of single gluon exchange, where the gluon propagator is calculated in tree level of a gluon condensate and a quark condensate. The kernel is divided into two parts: perturbative and non-pert,urbative. The non-perturbative part is determined by the vacuum condensate. Pseudo-scalar meson spectrum and decay constants are in good agreement with data.     

一种“裸眼”可视化检测溶液的pH值及细胞中铁离子的BODIPY类探针

以吡啶-2-甲酸(4-甲酰基苯酚)酯代替对羟基苯甲醛,将对羟基苯基引入到BODIPY染料的3-位,以高产率得到一个BODIPY类探针2。探针2易溶解到各种有机溶剂中,在甲醇溶液中的最大吸收和发射波长分别为570和585 nm,荧光量子产率达到0.9。当溶液的pH值从酸性过渡到碱性时,对羟基苯乙烯基团会慢慢失去质子,其溶液最大吸收波长发生红移,荧光发生淬灭,而且溶液颜色也发生明显的变化。因此,探针2可作为一种"裸眼"可视化的pH探针。此外,探针2对Fe~(3+)也有明显的响应,在溶液中加入Fe~(3+),探针2分子结构中乙烯基团发生断裂,其溶液最大吸收波长和最大发射峰均发生蓝移。因此,探针2也可以作为Fe~(3+)的比率型探针。同时探针2毒性较低、渗透性好、对Fe~(3+)选择性高,可以应用到细胞中检测Fe~(3+)的含量。