Micaceous soils are common in many tropical countries and regions,and in some locations with moderate climate.The soils ......

黄麻是天然韧皮纤维,由纤维素、半纤维素、木质素、果胶、脂肪、灰分和树胶组成。黄麻纤维很长,是一种天然长丝纤维,手感柔软,光泽......