They hold the helmet by the "D" ring and can be adjusted to fit any style helmet with a "D" ring.

通过D形环支撑头盔，而且可进行调整以适合任何样式的头盔。

youdao

It holds the helmet by the "d" ring and can be adjusted to fit any style helmet with a "d" ring.

通过D形环支撑头盔，而且可进行调整以适合任何样式的头盔。

youdao

The Ring-opening polymerization(ROP) of D-lactide(D-LA) catalyzed by bifunctional thiourea catalyst has been studied by performing density functional theory calculations at the B3LYP/6-31G(d) level.

用密度泛函理论在B3LYP/6-31G（d）水平上研究了双官能团硫脲催化丙交酯开环聚合反应的微观机理。

youdao

Some of it's not taking urgently enough some of these commitments and we'd like to see, for example, infrastructure spending kicked up and then ring-fenced.

BBC: Business group lists 15 ideas 'to boost the UK economy'

He has explored crystal growth, and developed, with a specialist in nature-related algorithms, a 3-D program mimicking the way crystals actually grow over millions of years (with this particular program, he and the scientists he has been working with made virtual crystals grow directly on a ring-like structure on their computer, almost instantly, then manufactured them with a 3-D printer).

WSJ: Ringing the Changes