铀系元素

The present project intends to develop a new compound only containing CHON, which can extract U, Pu and the minor actinides together form the acidic media to integrate the reprocessing.

本课题旨在寻找一种新的只含CHON的化合物，能够从酸性介质中同时萃取铀、钚和次锕系元素，实现后处理一体化。

One element of the lanthanide series and most of the elements in the actinide series are called trans-uranium, which means synthetic or man-made.

La系中的一个和Ac系中的大多数被人们叫做反铀元素，或者是人造的。

The concentration of neptunium and plutonium is extremely low in environmental samples. Additionally such samples have a complex matrix composition, which is to be taken into account for a proper analysis.

环境样品基体复杂，铀、镎和钚等锕系元素含量非常低，在复杂的生态条件下，这些核素常常具有复杂多变的化学形态，要准确测定其含量，必须要有灵敏可靠的检测方法。

Conventional radiochemical methods such as alpha spectrometry, neutron activation analysis, liquid scintillation system, fission track and gamma spectrometry for the quantitative determination of neptunium and plutonium often require complicated and time-consuming sample preparation and separation procedures.

研究环境中铀、镎、钚等长寿命放射性核素的精密测定，对保护公众安全和保护环境，对了解核设施的历史操作情况和现状，都具有重要意义。环境样品基体复杂，铀、镎和钚等锕系元素含量非常低，在复杂的生态条件下，这些核素常常具有复杂多变的化学形态，要准确测定其含量，必须要有灵敏可靠的检测方法。

Base on above studies, some conclusions were obtained as follows:(1) ore-forming background of the studied ferromanganese crusts are mainly controlled by intensity of Antarctic Bottom Waters and variations of material source;(2) it is confirmed that the ferromanganese crusts are mainly hydrogenetic and their composition are affected by volcanic and continental material simultaneously; there are no obvious phosphatization reconstruction and element reaction occurred in them, so they have important paleoceanological significance;(3) from researches on element occurrence modes in the new-type ferromanganese crusts and the lying sediments, it is proposed that there is no great biological affection on the crusts formation and their composition mainly came from the adsorptive action of the ferromanganese oxides in them;(4) two major types of ore-controlling factors are identified through compilation of ore-controlling factors, which are geological and oceanic factors;(5) considering the long-term variation trends of the crusts composition, combing the U-series and 10Be isotope dating results, it is proposed that the ore-forming processes of ferromanganese crusts in the studied areas can be divided into three major stages (5.6~2.8 Ma, 2.8~2.7 Ma and since 2.7 Ma), and then the activities of AABW since the Late Miocene, changes of input flux coming from volcanic and continental material are confirmed.

通过研究，得出如下结论：(1)研究区铁锰结壳的成矿背景主要受控于南极底流强弱及物源供给的变化；(2)证实铁锰结壳主要为水成成因，同时其物质组成也受一定程度的火山和陆源物质的影响；结壳自形成以来没有遭受到明显的磷酸盐化等成岩后期改造和元素再迁移，具有重要的古海洋学意义；(3)通过新型铁锰结壳及下伏沉积物元素赋存状态的研究，认为生物作用对研究区结壳的形成并没有很大的直接影响，其物质成分主要来自于结壳中铁锰氧化物的吸附作用；(4)在控矿要素的研究中，归纳出了地质与海洋两大类结壳控矿要素；(5)根据结壳成分长周期变化趋势，结合铀系和10Be测年结果，将研究区结壳的形成过程划分为三个主要阶段(5.6~2.8 Ma，2.8~2.7 Ma和2.7 Ma以来)，并确定了晚中新世以来研究区南极底流的活动情况、火山和大陆来源物质输入量的变化。

A member of the actinide series of transition elements, it is the most important transuranium element because of its use in certain types of nuclear reactors and in nuclear weapons.

锕系过渡元素及其化合物，是最重要的超铀元素，用作核反应堆燃料和核子武器装料。

A member of the actinide series of transition elements, it is the most important transuranium element because of its use in certain types of nuclear reactors and in nuclear weapon s.

锕系过渡元素及其化合物，是最重要的超铀元素，用作核反应堆燃料和核子武器装料。

Thorium along with uranium (U belongs to the actinide group of chemical elements.

钍(16日)同铀(U所属的77锕系元素。

In the sub-critical fast reactor core, the inner 7 subassemblies of CDFR were replaced with lead target subassembly, the control rod subassemblies were replaced with the subassemblies which contain MA and depleted uranium, and the radial blanket of CDFR were replaced with reflect subassembly.

次临界快堆堆芯在示范快堆堆芯基础上去掉中间7盒组件放置铅靶组件，控制棒组件用含贫铀和次锕系元素的组件代替，转换区组件用反射层组件代替。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。