天然铀

评价Snell实验&大块天然铀介质中平衡谱的平均裂变截面比

Evaluation of Snell Experiments & Average Fission Cross Section Ratio of Equilibrium Spectrum in a Natural Uranium

介绍CANDU堆的天然铀燃料循环以及最近开发的适合未来近期的先进燃料循环。

In this paper the natural uranium fuel Cycle and currently developed advanced CANDU fuel cycles in the near future are described .

铀（U）元素就是一个很好的例子。天然铀有两种同位素；较轻的负235可以裂变，较重的铀238则不会裂变。

The prime example is the element uranium ( U ), which occurs naturally as two isotopes-the lighter , fissionable U-235 and the heavier , non-fissionable U-238 .

生物样中~（90）Sr、~（137）Cs及土壤样中天然铀含量分析比对

Inter comparison of ~ ( 90 ) sr and ~ ( 137 ) cs contents in biologic samples and natural u in soil samples

最后，结合TQ核电公司经营情况，提出了天然铀采购建议策略。

The strategies of purchasing natural uranium are proposed in consideration of the practical situation on TQ Nuclear Power Company .

在条件实验的基础上提出了一个从中能18O离子照过的天然铀样品中简便、快速地分离钍的化学流程。

Based on the experiments , a chemical procedure used for rapidly separating thorium from the natural uranium irradiated by 18O ions was developed .

对1979、1980两年长江水系水体、鱼类及部分江底沉积物中天然铀含量进行了分析测定。所得结果表明，水中天然U含量变化，从上游至下游呈现逐渐减低的趋势。

The uranium content in water and fish in Yangtze River is determined in 1979 , 1980 . The results of U content are given , it shows a change trend from high to low in U content from upper to lower .

去污液对230Th污染的实际样品，在去污30min后去污率即达85%以上；对天然铀污染的实际样品，在去污2h后去污率达87%以上；

The decontamination efficiency is more than 85 % in 30 minutes for the 230 Th contaminated sample , and 87 % in 2 hours for the natural uranium contaminated sample .

60MeV／u~（18）O离子同天然铀反应钡同位素截面的测定

Determination of Cross Sections of Ba Isotopes in Interaction of 60 MeV / u ~ ( 18 ) O with ~ ( 238 ) U

由于CANDU堆对核燃料循环的固有灵活性，堆芯结构及运行方式不需作重大改变，即可完成从天然铀到RU的过渡。

Because of the inherent flexibility of nuclear fuel cycle in CANDU reactor , the transition from the nature uranium to the recycled uranium ( RU ) can be completed without any changes of the structure of reactor core and operation mode .

使用该方法对含铀量10~（-9）～10~（-7）g的树脂珠进行了铀同位素分析，对标准样品UTB-500，外精度达到±0.2%，对天然铀样品，外精度达到±0.5%。

This method has been used for isotopic analysis of uranium in NP-type chelate resin beads contained 10-9 ~ 10-7g uranium . For standard sample UTB-500 , the external precisions of measurements are within + 0.2 % , for natural uranium samples are within + 0.5 % .

本文报道了有环保系统14个环境放射性实验室参加的生物样中90Sr、137Cs及土壤样中天然铀含量的分析比对方法及其结果。

In this paper , the results of the 90 Sr and 137 Cs contents in biologic samples and the natural U in soil samples obtained in a joint effort by fourteen environmental radiation laboratories in the Chinese environmental protection system were analyzed and compared .

天然铀内照射限值的回顾

A review of the limits for the intake of natural uranium

关于天然铀摄入量限值的讨论

Discussion on the limits for the intake of natural uranium

我国天然铀氧化物的结构和化学特征

Structural and chemical characteristics of naturally-occurring uranium oxides in China

天然铀产品成本预测数学模型及电算程序

Mathematical models and computer programme of cost prediction of natural uranium products

西安市生活水源水体中天然铀含量调查

Investigation on Natural Uranium Concentrations in the Drinking Water Sources in Xi'an City

酒泉地区生态环境中天然铀的分布

Distribution of natural uranium in Jiuquan ecological environment

国际天然铀价格走势分析

Forecasting on the international market price of uranium

使用的燃料，无论是天然铀/钍还是乏燃料，都无需进行同位素分离。

The fuel , no matter the U , Th or spend fuel need not separation .

天然铀石墨慢化反应堆

Natural uranium graphite reactor

60MeV/u~（18）O离子同天然铀反应钍的放化分离

Radiochemical separation of thorium from the natural uranium irradiated by 60MeV / u ~ ( 18 ) O ions

燃煤电厂气载排出物中天然铀、钍所致周围空气污染浓度及地面沉积量的分布

Air concentration , ground deposition and their distribution of airborne natural uranium and thorium effluent from a coal-fired power station

β剂量刻度用的天然铀块外照射剂量分布区分新型洗涤剂的样品；

External dose distributions of exposure to natural uranium slab for calibration of beta absorbed dose distributing samples of a new detergent ;

本文介绍了应用级联撞击器和佩戴口罩的人头模型在天然铀燃料元件加工现场测定吸入气溶胶粒度的方法。

This paper describes a method for measuring particle size of inhaled aerosol with a phantom of human head wearing dust-proof mask anda cascade impactor .

通过对酒泉地区土壤、牧草、牛、羊和骆驼肉、骨中天然铀的分析测定，探讨了其自然分布及土壤牧草和牧草动物体间的转移情况。

The concentration of natural uranium in soil , forage grass , ox , sheep and camel at Jiuquan area was determined , and the data were analyzed .

并对如何使用此再制的核燃料提出两种方案，分别适用于压水堆和以天然铀为燃料的坎杜重水堆。

Scheme B in the article , i.e. a method of using the rebuilt used fuel from PWR to replace the natural uranium fuel for HWR , was discussed .

诸如澳大利亚、加拿大、南非等国家的天然铀储量丰富，相比直接出口，对天然铀进行提纯或许能给他们带来更多的利润。

Certain countries ( Australia , Canada , South Africa , among others ) have reserves of natural uranium and might like to profit from enriching them before exporting them .

用60MeV/u18O离子轰击天然铀靶，通过多核子转移反应产生重丰中子同位素237Th。

The natural uranium targets are bombarded by 18 O ( 60 MeV / u ) ions , and the heavy neutron rich isotope 237 Th is produced through the multi nucleon transfer reaction .

实验测量和理论计算的天然铀块的（？）′，（d，0）值与国外著者的值进行了比较，符合得很好。

The results experimentally measured and calculated theoretically of the Directional Absorbed Dose rate D ( d , 0 ) for a nature uranium slab have been compared with several authors and with a good agreement .