noun 下载 🔗分享 钋 A rare, highly radioactive chemical element (symbol Po) with atomic number 84. Examples : "Because of its extreme radioactivity and toxicity, working with polonium requires specialized equipment and strict safety protocols. " 由于钋具有极强的放射性和毒性,因此使用钋需要专门的设备和严格的安全措施。 element chemistry substance material science 与AI对话词汇游戏阅读练习