钷（化学元素）_百度百科
网页钷（Promethium），元素符号为Pm，原子序数为61，是一种具有放射性的镧系稀土元素之一。 已知有17种同位素和4种同质异能素。 其中最重要的是从铀裂变产物中提取或用中子照射146Nd制得的147Pm（半衰期2.64年）。
Promethium - Wikipedia
网页Promethium is a chemical element with symbol Pm and atomic number 61. All of its isotopes are radioactive; it is extremely rare, with only about 500–600 grams naturally occurring in the Earth's crust at any given time.
钷 - 维基百科，自由的百科全书
网页钷 pǒ （英語： Promethium），是一種 化學元素，其 化學符號 为 Pm， 原子序數 为61，属于 镧系元素，也是 稀土元素 之一。 钷是镧系及稀土元素中唯一一个没有 稳定同位素 的元素，其所有 同位素 都具有 放射性，其中壽命最長的是鉕-145， 半衰期 約17.7年。 由於缺乏長壽命的同位素，钷在自然界中极为稀有，同一時間在 地壳 中自然存在的钷只有大约500-600克。 原子序小於83（鉍）的元素中只有钷和 锝 没有稳定的 同位素，钷也是前84种 …
神奇的放射发光物质—稀土元素钷 - 知乎 - 知乎专栏
网页钷元素（Promethium）的名字来源于希腊神话中的英雄——天神普罗米修斯（Prometheus）。 在希腊神化传说中，众神之王宙斯为了永远统治大地，故意不给人类降火。
Promethium - Element information, properties and uses
网页Element Promethium (Pm), Group 19, Atomic Number 61, f-block, Mass [145]. Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images.
Promethium | Rare Earth Element, Atomic Number 61 | Britannica
网页Promethium (Pm), chemical element, the only rare-earth metal of the lanthanide series of the periodic table not found in nature on Earth. Conclusive chemical proof of the existence of promethium, the last of the rare-earth elements to be discovered, was obtained in 1945 (but not announced until.
Promethium bound: fundamental chemistry of an elusive element …
网页2024年5月22日 · It is known that promethium atoms have 61 electrons, with seven outer (valence) electrons — two in a 6 s orbital and five in a 4 f orbital — and that the element forms a stable +3 oxidation...
Observation of a promethium complex in solution | Nature
网页2024年5月22日 · One reason promethium (Pm) was so elusive for many years, despite a relatively low atomic number, is that it is the only element in the lanthanide (Ln) series (elements with atomic numbers 57–71)...
PROMETHIUM - Chemistry Explained
网页Promethium is a silver-white metal with a melting point of 1,160°C (2,120°F) and no measured boiling point. Its density is 7.2 grams per cubic centimeter. The physical properties of promethium are of less interest to scientists than its radioactive properties.
Chemists probe promethium’s properties - Chemical
网页2024年5月22日 · Promethium—named for the mythological Titan who stole fire from the ancient Greek gods and gave it to humans—is a mysterious element. Proposed in 1902 and first identified in 1945, promethium has practical applications in radiotherapy and nuclear batteries. But because all its isotopes are radioactive, it is challenging to study.
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