Technetium-99 (99 Tc) is an isotope of technetium that decays with a half-life of 211,000 years to stable ruthenium-99, emitting beta particles, but no gamma rays. It is the most significant long-lived fission product of uranium fission, producing the largest fraction of the total long-lived radiation emissions of nuclear waste .

2025年2月6日 · Technetium-99 (chemical symbol Tc-99) is a silver-gray, radioactive metal. It occurs naturally in very small amounts in the earth's crust, but is primarily man-made. Technetium-99m is a short-lived form of Tc-99 that is used as a medical diagnostic tool.

锝-99，核素符号99Tc，半衰期为2.111E+05a，是一个产额高、寿命长的裂变产物，在生态系统中有较大的迁移性。可作为超导材料和抗腐剂，用于航天航海和科学研究，制作稳定的β标准源等。

Technetium-99m (99m Tc) is a metastable nuclear isomer of technetium-99 (itself an isotope of technetium), symbolized as 99m Tc, that is used in tens of millions of medical diagnostic procedures annually, making it the most commonly used medical radioisotope in the world.

2021年6月7日 · Tc-99m是理想的医学示踪核素，在核医学诊断中应用很广泛，占全世界医疗用放射性元素的80%，其中90%用于扫描诊断。 Tc99m诊断体内出血部位：注射同位素后，用单光子断层扫描成像，连续扫描10-60分钟，如扫描阴性，则36小时内不同时间定时扫描，连续扫描中发现腹腔内异常放射性浓聚则定为阳性，即出血部位。 锝-99 (Tc-99)/锝-99m (Tc-99m)的生产防护及应急处理有哪些? Tc-99是一个产额高、寿命长的裂变产物，它在生态系统中有较大的迁移性。 …

Technetium-99 (99 Tc) is a major product of the fission of uranium-235 (235 U), making it the most common and most readily available isotope of technetium. One gram of technetium-99 produces 6.2 × 10 8 disintegrations per second (in other words, the …

The decay product of Mo-99, Tc-99m, is the workhorse isotope in nuclear medicine for diagnostic imaging. Tc-99m is used for the detection of disease and for the study of organ structure and function. Tc-99m is especially useful for nuclear medicine procedures because it can be chemically incorporated into small molecule ligands and proteins ...

Technetium-99 (Tc-99) is a radioactive metal. Most technetium-99 is produced artificially, but some also occurs naturally in very small amounts in the earth’s crust. Technetium-99 was first obtained from the element molybdenum, but it is also produced as a nuclear reactor fission product of uranium and plutonium.

2023年11月23日 · 锝，元素符号Tc，为银白色金属，原子序数为43，是首个以人工方法制得的元素。 锝总共有21种同位素，锝-99为最常见的同位素之一，而锝-99m，是锝-99激发态的同质异能核素，因为能量的不稳定而会发生 γ衰变 ，其在发射出γ射线后，会变回稳定态的锝-99。

锝-99（Technetium-99）是一种放射性同位素，它的性质、用途、制法和安全信息如下： 性质： 它的原子核不稳定，会通过放射性衰变转变成锝-99m或其他同位素。