fiber axis的用法和样例：
例句
- When this process occurs, molecular chains can orient in the fiber direction.
在此处理过程中，分子键能沿纤维轴向定向排列。 - It is proved that round-section fiber has Descartes rays, and its principle and characteristics are similar to the water drops producing the rainbow in the sun.
结果表明，透明圆形截面纤维在垂直纤维轴光线照射时有笛卡尔线产生，其原理与水珠在光照射时虹产生的原理相似。
