radioactive half life

简明释义

放射性物质的半衰期

英英释义

例句

1.The radioactive half life of uranium-238 is about 4.5 billion years, making it useful for geological dating.

铀-238的放射性半衰期约为45亿年，使其在地质年代测定中非常有用。

2.The concept of radioactive half life is crucial in nuclear medicine for determining how long a radioactive substance remains effective.

在核医学中，放射性半衰期的概念对于确定放射性物质的有效时间至关重要。

3.In radiation therapy, the radioactive half life of the treatment isotope affects how often patients need to receive doses.

在放射治疗中，治疗同位素的放射性半衰期影响患者需要接受剂量的频率。

4.Understanding the radioactive half life of isotopes helps scientists to date ancient artifacts using carbon dating.

了解同位素的放射性半衰期帮助科学家通过碳测年法对古代文物进行定年。

5.When studying environmental contamination, the radioactive half life of pollutants determines how long they will remain hazardous.

在研究环境污染时，污染物的放射性半衰期决定了它们会保持多长时间的危害性。

作文

The concept of radioactive half life is fundamental in the field of nuclear physics and chemistry. It refers to the time required for half of the radioactive atoms in a sample to decay into a more stable form. This process is not only crucial for understanding the stability of elements but also has significant implications in various fields, such as medicine, archaeology, and energy production. To illustrate the importance of radioactive half life, let us consider its application in medical treatments, particularly in cancer therapy. Radioisotopes, which are unstable isotopes that emit radiation, are often used in targeted radiation therapy. The radioactive half life of these isotopes determines how long they remain active in the body. For instance, iodine-131, with a radioactive half life of about eight days, is employed to treat thyroid cancer. The relatively short radioactive half life allows for effective treatment while minimizing damage to surrounding healthy tissues. In addition to medicine, the radioactive half life plays a pivotal role in archaeology, particularly in techniques such as radiocarbon dating. This method relies on the radioactive half life of carbon-14, which is approximately 5,730 years. By measuring the remaining amount of carbon-14 in organic materials, scientists can estimate the age of archaeological finds, providing valuable insights into past civilizations and historical events. Without the understanding of radioactive half life, our ability to date artifacts accurately would be severely limited. Moreover, the concept of radioactive half life is essential in the field of nuclear energy. Nuclear reactors rely on the fission of heavy elements like uranium-235 and plutonium-239. Understanding the radioactive half life of these materials helps in managing nuclear waste and ensuring safety protocols are followed. For example, some radioactive waste products have very long radioactive half lives, requiring secure storage for thousands of years to prevent environmental contamination. Furthermore, the radioactive half life is not a fixed value; it varies significantly among different isotopes. Some isotopes, like polonium-210, have a short radioactive half life of 138 days, making them highly radioactive and dangerous in a short period. In contrast, isotopes like uranium-238 have a remarkably long radioactive half life of about 4.5 billion years, indicating their stability over geological timescales. This variability underscores the diverse nature of radioactive materials and their applications. In conclusion, the term radioactive half life encompasses a crucial aspect of radioactivity that influences various domains, including medicine, archaeology, and nuclear energy. Its understanding is vital for harnessing the benefits of radioactive materials while mitigating their risks. As we continue to explore and utilize these powerful elements, the knowledge of radioactive half life will remain an essential component of scientific inquiry and technological advancement.

“放射性半衰期”这一概念在核物理和化学领域中是基础性的。它指的是样本中一半的放射性原子衰变为更稳定形式所需的时间。这个过程不仅对理解元素的稳定性至关重要，而且在医学、考古学和能源生产等多个领域具有重大意义。为了说明“放射性半衰期”的重要性，让我们考虑其在医学治疗中的应用，特别是在癌症治疗中。放射性同位素是不稳定的同位素，能够发出辐射，通常用于靶向放射治疗。这些同位素的“放射性半衰期”决定了它们在体内保持活跃的时间。例如，碘-131，其“放射性半衰期”约为八天，被用于治疗甲状腺癌。相对较短的“放射性半衰期”使得有效治疗成为可能，同时将对周围健康组织的损害降到最低。除了医学，“放射性半衰期”在考古学中的作用也至关重要，特别是在放射性碳测年等技术中。该方法依赖于碳-14的“放射性半衰期”，其大约为5730年。通过测量有机材料中剩余的碳-14，科学家可以估算考古发现的年龄，为了解过去的文明和历史事件提供宝贵的见解。如果没有对“放射性半衰期”的理解，我们对文物进行准确测年的能力将受到严重限制。此外，“放射性半衰期”在核能领域也至关重要。核反应堆依赖于重元素如铀-235和钚-239的裂变。了解这些材料的“放射性半衰期”有助于管理核废料并确保遵循安全协议。例如，一些放射性废物的“放射性半衰期”非常长，需要数千年的安全储存，以防止环境污染。此外，“放射性半衰期”并不是一个固定值；它在不同同位素之间差异显著。一些同位素，如钋-210，其“放射性半衰期”仅为138天，使其在短时间内高度放射性且危险。相比之下，铀-238的“放射性半衰期”长达约45亿年，表明其在地质时间尺度上的稳定性。这种变异性突显了放射性材料的多样性及其应用。总之，“放射性半衰期”这一术语涵盖了放射性的一个重要方面，影响着医学、考古学和核能等多个领域。理解这一概念对于利用放射性材料的好处同时降低其风险至关重要。在我们继续探索和利用这些强大元素的过程中，“放射性半衰期”的知识将始终是科学研究和技术进步的重要组成部分。