气相色谱-三重四极杆质谱法快速检测鸡蛋中氟虫腈及其代谢物

建立了QuEChERS前处理技术结合气相色谱-三重四极杆质谱（GC-MS/MS）分析鸡蛋中氟虫腈及其代谢物的快速检测方法。样品由乙腈提取,然后经150 mg MgSO₄脱水和50 mg N-丙基乙二胺（PSA）、50 mg C18净化,采用农药残留专用柱（TR-Pesticide Ⅱ）进行气相色谱分离,以定时反应监测（timed-SRM）模式进行检测,基质曲线外标法定量。结果表明,氟虫腈及其代谢物在1.0~200 μg/L范围内呈良好线性,线性相关系数（R²）均大于0.999,定量限为0.5~1.0 μg/kg;氟虫腈及其代谢物在3个添加水平（2、5和10 μg/kg）下的加标回收率为87.8%~111.5%,相对标准偏差（RSD,n=3）为2.0%~9.2%,该方法能满足欧盟规定的鸡蛋中氟虫腈及其代谢物的残留检测限量要求。     

4-(2-羟基苯基)-亚胺基-戊-2-酮的晶体结构和谱学性质研究

通过邻氨基苯酚与乙酰丙酮反应,合成Schiff碱4-(2-羟基苯基)-亚胺基-戊-2-酮,获其单晶,测定晶体结构,用UV-Vis,IR,^HNMR谱对其进行了表征。其晶体属正交晶系,空间群P2~12~12~1,晶胞参数:a=0.8840(10)nm,b=1.05250(10)nm,c=1.12260(10)nm。V=1.0450(2)nm^3,Z=4,结构偏离因子R=0.0320,ωR=0.0669,吻合因子S=0.949存在较强的分子间氢键,O(1)与相邻分子的O(2)之间的平均距离为0.2640nm。晶体结构分析和谱学性质研究表明,化合物存在亚胺烯醇式和烯胺酮式两种异构平衡。     

Mixed activation and mixed inhibition of the oxidoreductase activity of Rhus vernicifera laccase by different Pd~(2 ) ion concentration

Kinetic experiments were performed to study the effects of Pd2 ion on the oxidation of 5,6-dibro-mo-2,3-dicyanohydroquinone catalyzed by Rhus vernicifera laccase under condition of pH 4.5 and 30 × 0. 1℃ . The results showed that the mixed activation could be observed when Pd2 ion was at low concentrations. The competitive and non-competitive activation constants were 9 × 10 and 2 × 10-6 mol/L, respectively. With the increase of Pd2 ion concentration, the activation was gradually converted into mixed inhibition, and the competitive and non-competitive inhibition constants were 6 × 10-6 and 32 × 10-6 mol/L, respectively.     

1.6-缩水-2,4-二-氧-苄基-β-D-吡喃葡萄糖合成、开环及立体选择性成苷反应研究

以较好产率合成了3-位具有不同保护基的1,6-缩水-2,4-二-氧-苄基-β-D-吡喃葡萄糖, 并对其开环反应以及成苷反应的立体选择性进行了研究。     

两种含氨基吡啶衍生物铜(Ⅱ)配合物的合成和晶体结构

氨基吡啶与铜等金属离子所形成的配合物具备良好的磁学性质和结构的多样性,特别是在存在桥基的铜配合物中[1],对其结构的研究有助于理解发生在Cu-Cu原子间的磁交换作用,并揭示结构与磁学性质的相互关系[2,3].