放射性衰变

Radioactive series: Any of four sets of unstable heavy atomic nuclei that undergo a series of alpha decay and beta decay until a stable nucleus is achieved.

放射性系：四组不稳定的重原子核，通过一系列α衰变和β衰变直至达到稳定的核为止。

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。

In the International System of Units, the unit of radioactivity becquerel Harrell, called becquerels, symbol Bq, 1Bq equal to 1 second of radionuclides in the nucleus occurred within a decay, that decay 1Bq = 1 times / sec .

在国际单位制中，放射性活度的单位为贝可勒尔，简称贝可，符号为Bq，1Bq等于放射性核素在1秒钟内有1个原子核发生衰变，即1Bq=1次衰变/秒。

The decay of ~(99m)Tc source was used to verify experimentally that in the measurement of the number of atoms of a radioactive isotope in a sample at time t_0, the error introduced through the inaccuracy of its decay constant can be reduced to a much smaller value by the careful selection of the time of measurement or measurements of its radioactivity at around one life time (1/λ) after t_0 and doing the calculation.

本文用~(99m)Tc源的衰变实验证明了：在测量一个样品中在t_0时的一种放射性同位素的原子数时只需精心选择一次或多次测量其放射性的时刻在t_0后约该同位素的一个寿期(1/λ)，并进行计算，则由它的衰变常数或其半衰期(T1/2)的不准确性而引进的误差可以被降低到较小值。

Basic nuclear physics and fundamental measuring techniques: The basic nuclear physics involves the main types of nuclear decay, law of decay, definition and units of radioactivity and the interaction of radiations and materials.

核物理基础与放射性测量技术：内容主要是核衰变的四种类型、衰变规律、放射性活度及其单位；射线与物质的相互作用，以及γ计数器及液体闪烁仪测量的基本原理和放射性测量的统计误差。

Dinger, who was one of the pioneers of quantum mechanics, imagined putting a cat, a flask of Prussic acid, a radioactive atom, a Geiger counter, an electric relay and a hammer in a sealed box.

"薛定谔的猫"是最著名的未证实实验之一。1935年，量子力学的先驱之一，艾尔文·薛定谔提出了一个妙想：把一只猫、一个装有氢氰酸的烧瓶、一枚放射性原子、一个盖格计数仪、一个继电器和一把锤子一起放置到一个密封的盒子中组成一个装置，如果放射性原子衰变，盖格计数仪将探测到放射性，之后向继电器发送信号使其断开，从而释放之前被固定的锤子，锤子会将砸碎烧瓶并释放其中的氢氰酸，盒子里的猫于是被毒死。

In 1935 Erwin Schr dinger, who was one of the pioneers of quantum mechanics, imagined putting a cat, a flask of Prussic acid, a radioactive atom, a Geiger counter, an electric relay and a hammer in a sealed box.

"薛定谔的猫"是最著名的未证实实验之一。1935年，量子力学的先驱之一，艾尔文·薛定谔提出了一个妙想：把一只猫、一个装有氢氰酸的烧瓶、一枚放射性原子、一个盖格计数仪、一个继电器和一把锤子一起放置到一个密封的盒子中组成一个装置，如果放射性原子衰变，盖格计数仪将探测到放射性，之后向继电器发送信号使其断开，从而释放之前被固定的锤子，锤子会将砸碎烧瓶并释放其中的氢氰酸，盒子里的猫于是被毒死。

In the high energy physics laboratory called CERN, just outside Geneva in Switzerland, unstable muons (a type of fundamental particle that normally undergoes radioactive disintegration after about one millionth of a second) have been found to live longer by factor of thirty when travelling at high speed around a circular machine shaped like a large hollow doughnut.

在一个叫做 CERN 的高能量物理实验室，这个实验室在瑞士的日内瓦郊外，不稳定的μ介子（一种基本粒子，在百万分之一秒内会进行放射性衰变。）在绕着一个外形像中空的炸面圈形状的圆形机器中高速运行时，它的存在时间已经可以延长30倍了。

Dinger, who was one of the pioneers of quantum mechanics, imagined putting a cat, a flask of Prussic acid, a radioactive atom, a Geiger counter, an electric relay and a hammer in a sealed box.

&薛定谔的猫&是最著名的未证实实验之一。1935年，量子力学的先驱之一，艾尔文·薛定谔提出了一个妙想：把一只猫、一个装有氢氰酸的烧瓶、一枚放射性原子、一个盖格计数仪、一个继电器和一把锤子一起放置到一个密封的盒子中组成一个装置，如果放射性原子衰变，盖格计数仪将探测到放射性，之后向继电器发送信号使其断开，从而释放之前被固定的锤子，锤子会将砸碎烧瓶并释放其中的氢氰酸，盒子里的猫于是被毒死。

In 1935 Erwin Schr dinger, who was one of the pioneers of quantum mechanics, imagined putting a cat, a flask of Prussic acid, a radioactive atom, a Geiger counter, an electric relay and a hammer in a sealed box.

&薛定谔的猫&是最著名的未证实实验之一。1935年，量子力学的先驱之一，艾尔文·薛定谔提出了一个妙想：把一只猫、一个装有氢氰酸的烧瓶、一枚放射性原子、一个盖格计数仪、一个继电器和一把锤子一起放置到一个密封的盒子中组成一个装置，如果放射性原子衰变，盖格计数仪将探测到放射性，之后向继电器发送信号使其断开，从而释放之前被固定的锤子，锤子会将砸碎烧瓶并释放其中的氢氰酸，盒子里的猫于是被毒死。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。