|
hf n. high frequency（高频）的简写 high frequency（高频）的简写 Hf n 1: a grey tetravalent metallic element that resembles zirconium chemically and is found in zirconium minerals; used in filaments for its ready emission of electrons [ synonym: { hafnium}, { Hf}, { atomic number 72}] 2: 3 to 30 megahertz [ synonym: { high frequency}, { HF}] Hydrofluoric \ Hy` dro* flu* or" ic\, a. [ Hydro-, 2 fluoric.] ( Chem.) Pertaining to, or containing, hydrogen and fluorine; fluohydric; as, hydrofluoric acid. [ 1913 Webster] { Hydrofluoric acid} ( Chem.), a colorless, mobile, volatile liquid, { HF}, very corrosive in its action, and having a strong, pungent, suffocating odor. It is produced by the action of sulphuric acid on fluorite, and is usually collected as a solution in water. It attacks all silicates, as glass or porcelain, is the agent employed in etching glass, and is preserved only in vessels of platinum, lead, caoutchouc, or gutta- percha. [ 1913 Webster]
|
安装中文字典英文字典查询工具!
中文字典英文字典工具:
英文字典中文字典相关资料:
|