通气孔通常在翼尖或尾部, 这些通气孔可以保持压力恒定.Vents, usually at the wing tips or tail, keep the pressure constant.这种简单的测试只需要分析鹦鹉的翼尖.The simple test required only a feather tip for analysis.注意你的翼尖.Watch out for your wing tips....
你在标签上涂胶了 吗 ?Have you gummed the labels?在使用拉伸聚丙烯薄膜覆膜时,必须在膜上涂胶.In the use of plastic mulch for BOPP film at prbroin gelatinize.涂胶机固化剂系统,为全封闭系统,杜绝了空气的混入.The curative agent system is completely closed and air proof....
Limonene needed in recycling foamed polystyrene was extracted from the ear of schizonepeta tenuifolia using ligroin.本文研究从荆芥穗中提取回收聚苯乙烯所需的柠檬烯,其方法是溶剂萃取....