针对常规抽油泵使用中易发生磨损、砂卡和脱扣的弊端,研制了高效 防 砂抽油泵.A high - efficiency anti - sand pump is developed for oil recovery in sandy wells.半导体脱扣器电路与智能脱扣器电路有明显的差异性,有各自的优点.There is a difference between semiconductor release circuit and intel...
The molluscacidal medicated additive is bromoacetyl bromide or niclosamide.所述的灭螺药物添加剂为溴乙酰胺或氯硝柳胺.The writer analyzed the and disadvantage on phasing - out methyl bromide in China.本文分析了我国淘汰甲基溴的利弊.Conclusion 0.1 % benzalkon...