应用常规化学分析方法测定了杭州城郊养殖场的17个畜禽粪样（10个猪粪，7个鸡粪）的养分及重金属含量，并应用固相萃取．高效液相色谱串联质......

The overdependence on crude oil in African countries warrants the need for alternative sources of energy. A 56-litre-cap......

Impurity redistribution during cotton carding was investigated. The content and size of impurity in card sliver,takerin ......