d-ring

bridged-ring system

[化] 桥环系统

closed-ring

闭合环
闭环

closed-ring hydrocarbons

[建] 闭环烃

d-rings

(d-ring 的复数) abbr. capital-D-shaped ring 形状同大写字母D的环

gold-ring

n. 金戒指

liquid-ring compressor

[化] 液环压缩机(尤指)水环压缩机

liquid-ring pump

[化] 液环泵

liquid-ring vacuum pump

[化] 液环式真空泵