湘西、湘中新元古界—古生界微量元素地球化学特征

湘西湘中新元古界—古生界是金锑砷等金属矿床的重要产出层位。岩石地层微量元素地球化学研究对于认识矿源层以及矿床成因具有重要的意义。本文根据单一地球化学过程产生的地质体中元素含量趋向于正态分布的认识 ,对于湘西湘中的新元古界—古生界中的微量元素进行了系统研究 ,结果表明 :新元古界的板溪群和震旦系是Au、Sb、As的重要含矿建造 ;Pb在奥陶系、志留系中显著富集 ;Hg在寒武系和奥陶系中明显富集。古生代各地层中Sb、As、Hg、Au等成矿元素均不同程度地受到后期成矿作用的影响 ,泥盆系和石炭系中Sb、As的高平均含量是由成矿叠加作用所引起的。     

包裹块石煤固氟燃料制备工艺研究

石灰或烧制白云岩与粘土、低氟无烟煤粉作为包裹材料，通过正交试验方法，对陕西省紫阳县蒿坪镇高氟块状石煤进行了固氟效果研究。结果表明，影响包裹石煤固氟效果的主要因素是无烟煤粉和石灰，影响顺序是无烟煤粉〉石灰〉粘土。最佳制备工艺条件为石煤块：无烟煤粉：石灰：粘土=70：10：10：5，固氟率达91．9％。     

Environmental selenium in the Kaschin–Beck disease area,Tibetan Plateau,China

Now, there is a decreasing trend for the prevalence rate of Kaschin–Beck disease (KBD) in most parts of China, but the disease is still active and severe in the Tibetan Plateau for some reason. To further explore the role of selenium in the occurrence of KBD, We collected samples including drinking water, cultivated topsoil, Highland Barley grains, and tsamba in Rangtang County and Aba County, Sichuan Province and determined concentrations of selenium by Hydride Generation Atomic Fluorescence Spectrometry. Levels of selenium in the environment were analyzed in detail. Selenium in the soil–plant–food system and their relationship with prevalence rate of KBD were also discussed. The results indicate: (a) the levels of environmental selenium are very low and the study area belongs to a selenium-deficient ecological landscape; (b) the KBD becomes much more severe with decreasing environmental selenium under the selenium-deficient condition. Namely, the lower the environmental selenium is, the more severe the disease is; (c) soil selenium deficiency plays a critical role for the prevalence of local KBD, and more factors inducing selenium deficiency should be more concerned in the future.     

硒酵母对地方性砷中毒病人排砷作用

观察了硒酵母治疗地方性砷中毒病人１４个月的排砷效果，结果显示，硒酵母治疗３个月后，治疗组发，血、尿砷的下降速度比对照组明显加快至１４个月，治疗组发、血尿砷分别下降７７．８％，８８．２％和７３．１％，与对照组相比，治疗组发砷和血砷的下降幅度明显增大。     

The selenium status of sheep in Britain as indicated by wool selenium concentration

A correlation between the selenium concentration in wool and blood erythrocyte glutathione peroxidase activity (GSHPx) from sheep in W. Derbyshire, a high selenium area and N. Wales and Romney Marsh, low/marginal selenium areas is reported.Soil and herbage selenium concentrations were significantly correlated with wool selenium levels and GSHPx activity.A significant difference was found between wool selenium concentrations and between GSHPx activities from sheep in W. Derbyshire and those animals sampled in N. Wales and Romney Marsh. 90% of wool samples from the low/marginal areas gave concentrations below 0.125 g Se/g. 6.125 g Se/g wool is suggested as a threshold value for selenium in wool from sheep grazing low/marginal areas.Seasonal peaks in wool selenium concentrations and GSHPx activities are found in March and June respectively. Supplementary feeds, which contain added selenium, given to livestock during the winter season may be responsible for these seasonal differences.GSHPx activity data reported in this study records higher sheep selenium levels than those reported in the 1979 survey by Andersonet al. This increase is attributed to the addition since 1979 of selenium to feeds and drenches.Wool is proposed as an accurate and less costly measure of sheep selenium status.     

Environmental behaviors of selenium in soil of typical selenosis area, China

Daba Mountain area is one of the two endemic selenosis areas in China,which may relate with the environmental behaviors of selenium (Se) in soil.This study focuses on the concentraion and distribution of Se and its relationships with some other elements in natural soil in the area.The average concentration of Se in Daba Mountain soils was 14.3 times higher than the value cited for natural soil background worldwide,suggesting that soils in the region were contaminated by the element.The finding was confir...     

基于ICRP生物动力学模型的贫铀辐射危险估计算法

针对线性年龄相关剂量学程序PLEIADES （ Program for Linear Age - dependent Dosimetry）计算贫铀辐射危险存在的影响因素较多、系数不确定性大、使用不便的问题,基于ICRP生物动力学模型,采用美国原子管理委员会编制的放射性物质工具箱中提供的典型条件下铀的各同位素剂量转换系数,分析了不同背景下剂量的影响因素,给出了贫铀的辐射危险概率的简化计算方法,并同PLEIADES的结果相比较。分析表明两者结果吻合较好,该方法原理简单,使用方便,适合于对贫铀辐射危险的估算。     

石煤暴露环境发氟分布规律及影响因子

为了探明石煤暴露环境中发氟含量的分布规律及影响因子,结合病情调查,采集发样进行元素含量测定.结果表明,石煤暴露环境发氟含量个体差异显著,呈非正态分布,平均值为67.08±64.68μg/g,变异系数为96.42%;发氟含量同Ca、Mn、Se的含量呈显著正相关,同Ti含量呈显著负相关;因子分析显示发氟含量分布除受体内生化反应控制外,与表生地球化学环境、膳食结构以及饮用水的水质等因子也密切相关.     

不同金属离子对Vc引发的小鼠肝匀浆自由基反应的影响

以小鼠肝匀浆脂质过氧化产物丙二醛(MDA)的OD_532nm值(MDA-OD_532nm)作为测定自由基反应的间接指标,研究了Hg²⁺、Mn²⁺、Ni²⁺、Cd²⁺、Cr³⁺、SeO^2-₃等离子和As₂O₃水溶液在Vc引发自由基反应体系中的作用.结果表明:Cr³⁺与Mn²⁺具有显著的抑制作用;Hg²⁺、Cd²⁺与As₂O₃对自由基反应有促进作用;Ni²⁺、SeO^2-₃对Vc引发小鼠肝匀浆的自由基反应作用不明显.     

初论世界低硒带

本文根据作者所在研究组多年研究发表的数据、综合世界上有关环境和生物中硒的研究资料,分析了植物、动物和人体组织中硒在世界上基本一致的带状地理分布特征。提出世界上有一低硒带,这一低硒带以地球上南北半球中高纬度温带湿润、半湿润森林、森林草原带和地中海型自然地区为中心。并以原生地理环境低硒生态链所引起的人和动物硒反应症的分布为特征。从原生环境和次生环境关系的角度提出环境中硒的区域分异在环境研究和评价中的意义。