汽机油系统法兰禁止使用塑料垫、橡皮垫（含耐油橡皮垫）和石棉纸垫。
参考答案：对
Their business flourished at its new location a year later owing to their joint efforts and hard work.
A．prevailed
B．failed
C．boomed
D．shrank
阴、阳离子交换器大修项目及标准有哪些？
