晶质铀矿自发裂变产生钌,银,碲的同位素探索

为了阐明对铀的自发裂变现象，采用热电离质谱测定法对几种类型晶质铀矿样品的Ｒｕ，ｔＥ和Ａｇ的同位素组成作了测定，由于自发裂变碎片有可能加入天然同位素中，在几个样品中的Ｒｕ，Ｔｅ清楚地显示出了＾９９Ｒｕ，＾１０１Ｒｕ，＾１０２Ｒｕ，＾１０４Ｒｕ，＾１２８Ｔｅ，＾１３０Ｔｅ同位素测量中得到裂变成因的Ａｇ，从Ｍｏｒｏｇｏｒｏ（坦桑尼亚）某晶质铀矿得到的Ｒｕ裂变模式表明，这种晶质铀矿可能已经处于中子诱发＾２     

Th-and U-bearing minerals in the SE Mediterranean margin of Spain

This paper presents the first specific study of the Th-and U-bearing minerals, which were recently found in the SE Mediterranean margin of Spain (El Hoyazo area,Almeria province). These minerals are REE phosphates (mainly monazite) which occur as amoeboidal-to-elongate inclusions,from around 10 120μm to 120μm, hosted in single garnet crystals from dacite lavas and metamorphic rocks from the El Hoyazo Volcanic Complex. Th and U contents are higher than 1 wt%, with 3.04 to 5.62wt% for Th02, and 0.7 to 1.75 wt% for UO2. Both elements are also found in xenotime (ThO2:0.24,UO2:0.27wt%). Given that the erosion of the volcanic source rocks has generated a “placer-type” deposit of monazite sands and that garnets (main carriers of monazite) are being commercialised, an environmental monitoring and management plan should be urgently executed in the area.     

比值分析及其在伴生元素评价中的应用

比值分析是利用伴生元素含量(x)与主元素含量(c)在矿石中的比值(α=x_0/c_0),在矿物中的比值(b=x_i/c_i)以及两者的比值(称比值系数k=b/α),对伴生元素赋存规律进行分析研究的方法。b值和矿石中仅有一种矿物含某种伴生元素的a值,可确切了解伴生元素自身变化、富集规律及其在载体矿物中分布的均匀程度;矿石中与各矿物相关联的k值具有如下关系:k_1+k_2+…=1,据此可确定伴生元素在各有关矿物中的分配情况和判断赋存有该种伴生元素的矿物是否全部查明。