1.A new technology for fermenting production of lactic aicd by using corn as raw mate rial was studied.
介绍了用玉米为原料发酵生产乳酸的新工艺。
4.One mate rial can be distinguished from another by their physical properties: color, density, specific, heat and so on.
一种材料与另一种材料的区别在于他们的物理性能:颜色、密度和比热等等。