需挖砂造型的铸件在大批量生产中采用什么造型方法，可大大提高生产效率。()
A. 刮板造型
B. 分模造型
C. 假箱或成型模板造型
D. 活块造型
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临床上延缓磷酸锌水门汀凝固速度的常用方法是粉和液放在______上进行调拌。
If zinc phosphate cement is contaminated by moisture during setting()
A. its solubility increases
B. its hardness increases
C. its pH increases
D. its fluoride release increases
The following is a description of a glass-ionomer cement’s fluoride release pattern()
A. initial low-rate release，foilowed by long，low-rate release
B. initial high-rate release，followed by long，low-rate release
C. high．rate release throughout the GIC’s lifetime
D. polycarboxylate cement
可锻铸铁中的团絮状石墨由下述方式获得 ()
A. 由白口铸铁经高温退火从渗碳体分解而得到
B. 直接从液体中结晶而得
C. 由灰口铸铁经锻造而得
D. 上述说法都不对
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