方形截面管
tube bundle with square section
方形柱体蝇眼透镜
Quadrate column fly-eye lens
古代箜篌的方方面面
Aspects of the Ancient Konghou
正方形截面长隧道
long square-section tunnel
U形截面柱
column of U-shaped cross-section column
等离子体截面形状
Plasma cross section shape
等肢钢筋混凝土T形截面柱
R C T-shaped columns with equal legs
卵形截面柱壳
Egg-shaped cylindrical shell