分子间作用力主要有______和________。
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冷轧厂1780机组轧机支撑辊直径()mm;工作辊直径()mm 。
Patients should not function on crownsjust after cementation ofthe crowns with a chemically-activated resin cement because()
A. the tooth will be sensitive
B. the bond needs time to mature
C. the crown may fracture
D. the cement shade will change drastically
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