硒摄入对肉牛组织中镉、铅、铜、铁、锌含量的影响

本研究旨在探讨硒元素摄入对动物体内必需微量元素铜、铁、锌和有害元素铅、镉含量的影响及其机理,为降低铅、镉在食物链中的迁移和积累的控制技术提供依据。试验选用20头杂交牛,随机分为2组,每组10头,对照组饲喂基础日粮,试验组在精饲料中以预混料的形式添加亚硒酸钠1.0 mg/kg。饲养试验期为150 d,饲养试验结束后,屠宰采集各组织样品测定铅、镉、铜、铁、锌含量。结果表明:添加亚硒酸钠后对肉牛日增重影响不显著(P>0.05),但能极显著降低肉牛心脏中铅、镉的含量和血液中铅的含量(P<0.01),极显著增加胃、肾脏、肝脏等组织中铅和镉含量(P<0.01);同时也增加铜、锌、铁在胃和铜、铁在肝脏中的蓄积(P<0.05)。结果提示,在饲料中添加微量元素硒,可以改变铅、镉、铜、锌、铁在动物体内各器官和组织中的分布水平,但不能有效降低肉牛各组织中铅、镉的蓄积。

Chemical Associations of Heavy Metals in the Sediments near Bailonggang Sewage Discharge Outlet of Shanghai

The five chemical associations of heavy metals have been extracted continuously using the Tessier extracting method. Results show that Cu, Pb, Fe, Zn and Cr in the sediments are mainly distributed in residual fraction, while the major chemical association of Mn is carbonates. Carbonate heavy metals are converted into Fe-Mn oxides in autumn. And in the low tidal flat, after carbonates have changed into ionic heavy metals, some of the elements are transported to the overlying water. Cu, Pb, Fe and Mn have good correlations with each other, and Zn, Cr also show their similarity of chemical behavior in the sediments.

微波等离子体-原子发射光谱仪(MP-AES)测定葡萄酒中10种金属元素方法

采用常压消解-微波等离子体原子发射光谱仪（MP-AES）测定了葡萄酒中铅、镉、锰、铁、铜、锌、钒、铝、铬、镍10种金属元素,实验结果表明,标准曲线均有良好线性关系,10种元素方法回收率为85.0%-120.5%,RSD%为0.41%-3.12%。方法简便快捷、成本低廉。