The ball is a hollow aluminum sphere covered with a thick layer of polyurethane rubber.
这个球是空心球体，表面有一层厚厚的聚氨酯橡胶。
Study on Preparation and Property of Ba-Ferrite Hollow Microspheres;
空心钡铁氧体微球的制备与性能研究
Study on Fabrication of Monodispersed Hollow Barium Ferrite Submicrospheres;
单分散钡铁氧体亚微空心球的制备研究
Study on Preparation and Property of Hexagonal Ferrite Hollow Microspheres;
六角晶系铁氧体空心微球的制备与性能研究
Controllable Fabrication of Cobalt Ferrtie magnetic Hollow Spheres and Studies on Their Applications
钴铁氧体磁性空心球的可控制备及应用研究
Construction Technology of Welding Hollow Ball Grid in Beijing Normal University Gymnasium
北京师范大学体育馆焊接空心球网架施工技术
Preparation and Characterization of Beehive-like BaFe_(12)O_(19) Hollow Microspheres
蜂窝状钡铁氧体空心微球的制备与表征
Innovative design for energy efficient air conditioning of the tennis hall and swimming pool in Shenyang Olympic Sports Center
沈阳奥体中心网球游泳馆空调节能创新设计
The practical application of hollow steel ball, solid bolt ball and mine bolt ball to architectural engineering is introduced in this article.
介绍空心钢球、实心螺栓球体和水雷式螺栓球体在建筑工程中的实际应用
A tennis ball is hollow,but a base ball is solid.
网球是空心的，但棒球是实心的。
Temperature-triggered Assembly of Ta_2O_5 Hollow Microspheres
热诱导组装Ta_2O_5空心微球
Controlled Synthesis and Self-assembly of AlOOH and Low-cost Preparation of Al_2O_3 Nanopowders and Nanomembranes
AlOOH核壳、空心球的控制合成与组装及Al_2O_3纳米粉体、薄膜的廉价制备
Preparation and characteristics of Ni_xFe_(3-x)O_4-encapsulated hollow glass spheres by ferrite plating
Ni_xFe_(3-x)O_4包覆空心玻璃微球的铁氧体化学镀制备及性能(英文)
New Globe-tube Soldering Techoology of Soldering Hollow Globe-Net-Shelf Struct ure;
焊接空心球网架结构球—管焊接新工艺
The entire cell aster with the exception of the centrosome.
空心体，吸收体除中心体外的整个星体
A body with the shape of a sphere, especially a representation of the earth in the form of a hollow ball.
球，球状物球体，球状物，尤指中空的球的形式的地球仪
To save weight, the frame- similar to a monocoque body of a race car- was made up of small glass hollow spheres contained in an epoxy matrix.
为了减轻重量，主要骨架（似赛车的单体结构）由包裹在环氧化物里的小空心玻璃球体所组成。
medicine ball
(锻练身体用的)实心皮球