放射性元素

There are 8.6%~10.91% foreign matter in the sphenes, in which radioactive elements of strontium, cesium and uranium range from 4.26% to 4.58%. The change of structural cell parameters of sphenes is still very little,Δa=-0.0009 nm~0.0041 nm,Δb=0.0018 nm~0.0004 nm,Δc=0.0002 nm~0.0048 nm,Δβ=-0.10°~0.09° with high crystallinity of 99.27%~96.46%. Though, the age of sphene from the Fenghuang Mountain is about 1000 Ma, and experienced 775 Ma~1758 Ma geological evolvement and alpha decay, its crystallinity only decreased 3%, and its crystal shape and structure are still fine, indicating that sphene is of good ability to solidify radioactive elements. Therefore, sphenes are ideal minerals for solidifying nucleus waste.

通过对北祁连牛心山变质杂岩体中榍石(775Ma)和山西凤凰山花岗岩中榍石(1758Ma)的XRD及EDS等测试与研究，结果表明：两地榍石的杂质元素质量分数高达8.6%~10.91%，放射性核素锶、铯和铀的质量分数达4.26%~4.58%；晶胞参数的变化极小，△a=-0.0009nm~0.0041nm、△b=0.0018nm~0.0004nm、△c=0.0002nm~-0.0048nm、△β=-0.10°~0.09°，结晶度仍高达99.27%~96.46%，榍石经过10×10^8a的地质作用，结晶度仅减少了3%，显示榍石固化放射性系列核素的能力较强，虽经历了约775Ma~1758Ma的复杂地质演化及其所含放射性核素的衰变作用，其晶体结构完好，稳定性极高，是值得期待的理想核废物固化矿物。

We summarize the study of geochemistry of the Co rich crust, and explain the diffusion of elements in the Co rich crust and the exchange with ambient seawater. Besides, we discuss the effect of phosphatization and substrate rocks on the composition of the Co rich crust. We also introduce the application of stable isotopes (including the stable isotopes of Pb, Nd, and Hf), radioactive...

概述了富钴结壳地球化学的研究成果阐述了富钴结壳中元素的扩散及与周围海水的交换，基岩和磷酸盐化事件对富钴结壳组成的影响分别介绍了稳定同位素(Pb、Nd和Hf的稳定同位素)、放射性同位素(Be、U和Th的放射性同位素)及元素(常量和微量元素、稀土元素)在富钴结壳古海洋学研究上的应用。

Kelp: Kelp alginic acid can slow down the rate of intestinal absorption of radioactive strontium, so that strontium excreted, and therefore has a role in the prevention of leukemia.

海带：海带中的褐藻酸能减慢肠道吸收放射性元素锶的速度，使锶排出体外，因而具有预防白血病的作用。

The researchers fired a beam of calcium ions, each containing 20 protons, into a target of californium, a highly radioactive synthetic substance with 98 protons.

他们轰击了一束每个原子中含有20个质子的钙离子，得到了锎，一种原子核中含有98个质子的更高级人造放射性元素。

The contents of the natural radioactive elements,〓 and 〓 incrystal will give a strong effect on the experimental results.

CsI(T1)晶体内部天然放射性元素〓和〓的含量对实验的结果有很大的影响。

To lawrencium of 15 radioactive elements with increasing atomic numbers.

15个从''。'锕'。''到铹的原子量递增的放射性元素。

On the other hand, as the pollution-carry capacity of the atmosphere is being exhausted, a globally effective ban on ozone depleting substances appears warranted to avoid globally distributed environmental,public health or ecnomic detriments due to increased UV-B raditation.

另一方面，大气污染的运输能力正在被耗尽，全球的对于消耗臭氧层的物质的使用的有效控制显得更为重要，它可以有效地解决由于放射性元素 UV-B 增加带来的全球性环境、公共健康和经济毁损问题。

In order to acquire the relationship between the metamict degree of zircons and contents of radio-elements, zircon samples of this paper from kimberlites of Mengyin, Shandong Province are tested by CL, Raman, SHRIMP etc.

为获得鋯石变生程度与放射性元素质量分数之间的相互关係，对来自山东蒙阴金伯利岩中的鋯石进行了阴极发光、激光拉曼光谱、离子探针测试和研究。

The relationships between the intensity of gamma-radiation and radi- oactive elements content of ore bed have proposed,and made an exhaustive analysis of the various methods solving the uranium content(iteration, inverse matrix and the decomposition suggested by author).

文中提出了比较完整的伽玛强度与矿层中放射性元素含量的关系式，对求解铀含量的各种方法(迭代法、逆阵法和作者提出的分解法)作了详尽的分析，列举了不同类型铀矿床伽玛测井实际资料的电算对比结果。

Like fission-track dating, alpha-recoil track dating is based on the accumulation of unclear particles which are re-leased by natural radioectivity and produce etchable tracks in solids.

中文摘要：与裂变迹径定年类似，α反冲径迹定年（Alpha-Recoil Track）也是基于天然放射性元素所释放核粒子在固体中产生可蚀刻径迹的积累。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了