a grey tetravalent metallic element that resembles zirconium chemically and is found in zirconium minerals; used in filaments for its ready emission of electrons
同义词:hafnium, atomic number 72
3 to 30 megahertz
同义词:high frequency
详细解释:
HfNONE(无词性)The symbol for the element hafnium元素hafnium的符号