【机】 放射衰变律

redioactive parent law of causality norm of international law maturity of law subject of international law code of mercantile law law of gravitation rule of law code of civil law cobwebs of the law table of arithmetic law law of nature law of redioactive displacement law of radioactive decay decay law hyperbolic decay law radioactive decay law exponential decay law redioactive series decay of activity decay of lumber rate of pulse decay period of decay