A radiotracer is a radioactivecompound that is safe to inject into patients and shows up clearly on a scan.
这种放射示踪剂是一种具有放射活性的复合物，具有注射安全且扫描显示清晰的优点。
2
Workers are attempting to remove the radioactive water from the tsunami-ravaged nuclear compound and restart the regular cooling systems for the dangerously hot fuel.