Spectroscopic study on the photophysical properties of chlorine substituted tetraphenylporphyrin-histidine and its zinc(Ⅱ)complexes

The photophysical properties of ortho-CI,meta-CI and para-CI substituted tetraphenylporphy-rin-histidine and their zinc (II) complexes have been studied by means of steady-state absorption and fluo-rescence spectroscopies, as well as time-resolved fluo-rescence spectroscopy. For the cases of both free-base and zinc complexes, it was found that the ortho-chlorine substitution onto the phenyl rings significantly altered the fluorescence quantum yield, thefluorescence lifetime and the ratio between radiative and nonradiative deactivation rates of the porphyrin chromophore, i.e. the photophysical parameters were quite different from those of meta- and para-substituted compounds. On the other hand, however, the introduction of covalently-linked histidine did not exert much effects on the photophysical behavior of the porphyrin chromophore. The results are interpreted interms of the steric effect and the heavy-atom effect from the chlorine atoms substituted onto the phenyl rings.     

用TAPP分光光度法测定面粉中的微量锌

四-(对三甲铵苯基)卟啉,在乙二胺存在下与Zn(Ⅱ)形成络合物,据此提出用分光光度法测定微量锌的方法.该络合物最大吸收波长在425nm.表观摩尔吸光系数为3.42×10~5.锌量在0—4.5μg/25ml范围内遵从比尔定律.研究了共存离子的影响.本法可直接应用于测定面粉中的微量锌.     

两种新型卟啉-5-氟尿嘧啶化合物的合成

以对羟基苯甲醛、茴香醛为主要原料,合成了2种新型卟啉-5-氟尿嘧啶化合物,并通过红外光谱、紫外光谱、核磁共振氢谱、碳谱和电喷雾质谱测试技术对化合物结构和组成进行了确认.探索了目标化合物的合成及分离纯化的条件.选择非质子极性溶剂DMF为反应溶剂,反应温度为120 ℃,TLC检测反应的进行,大约10 h反应完全,反应收率为49.0%～50.6%.采用薄层层析硅胶G作固定相,以V(氯仿):V(丙酮)=15:1作洗脱剂,可得到较好的分离效果.     

四—（对—癸酰氧基）苯基卟啉及其配合物的红外光声光谱

研究四-（对-癸酰氧基）苯基卟啉及其配合物在190-3600cm^-1范围内的傅立叶变换红外光声光谱,对主要谱带进行经验归属。结果表明,3318.0cm^-1和968.4cm^-1处的吸收谱带分别是四-（对-癸酰氧基）苯基卟啉N-H键的促缩振动和面内弯曲振动,生成配合物后这些谱带消失。-250cm^-1处的吸收谱带是M-N键伸缩振动和卟啉环变形振动的复合振动,-327cm^-1处的吸收谱带是M-Cl键的伸缩振动,金属敏感带出现在-1354cm^-1,-1019cm^-1,-991cm^-1,-791cm^-1,-737cm^-1,-633cm^-1和-236cm^-1处。     

二恶英的危害及防治

本主要介绍了二恶英的来源、危害、控制对策和措施以及分析研究进展。