The Food and Drug Administration said that it found one positive sample of U.S.-made infant formula containing melamine 'at very low trace levels.'
美国食品和药物管理局(FDA)称，在一份美国产婴儿配方奶粉样本中检测出“含量极低的”三聚氰胺。
2
With dynamic optical theory, the image motion compensating group formula of the zoom optical system is derived, and the trace curve of the image motion compensating group is plotted.
首先应用动态光学理论推导出变焦光学系统的像移补偿组公式，从而得到像移补偿组的轨迹曲线。
3
For this new type fiber end, the ray refraction formula at a spherical surface and the ray trace equation are used to analyze ray transformation properties.