在地质分层时应由自然电位和微电极曲线确定渗透层的位置,以()曲线和微电极曲线确定渗透层的顶、底界面。
A、短梯度电阻率
B、中子测井
C、密度测井
D、伽马测井
参考答案:A
A new technique ____ out, the yields (收成) increased by 20% .
A.having working
B.having been working
C.has worked
D.had been worked
25℃时,在20 mL 0.1 mol/L NaOH溶液中逐滴加入0.2 mol/L醋酸溶液,pH的变化曲线如图所示,有关粒子浓度关系的比较中,不正确的是
A.在A点:c(Na+)>c(OH-)>c(CH3COO-)>c(H+)
B.在B点:c(Na+)=c(CH3COO-)>c(OH-)=c(H+)
C.在C点:c(CH3COO-)+c(CH3COOH)=2c(Na+)
D.在C点:c(CH3COO-)>c(Na+)>c(H+)>c(OH-)