a“U”Circumferential Notch

U notch

U-shaped notch

section u-u u-u

230Th-234U-238U dating

U U

U U tube

U(Ⅲ)-U(Ⅳ) isotopic exchange

view u-u

colo(u)r and colo(u)r-difference meter

double offset expansion U bend U

Seal-u-cup U

single U shaped and double U shaped vertical borehole

U bend U

u bolt plate U

U bolt U

u press u

U q*$p (u 2) model

u statistic u