(A)1.0~2.0Mpa (B)1.0~2.20Mpa (C)0.8~2.20Mpa (D)1.0~1.50Mpa
(A)不變 (B)相應(yīng)提高 (C)相應(yīng)降低 (D)由乙苯轉(zhuǎn)化率確定