摘要:The wear resistance of nozzle tips used in malaria eradication programmes has, in the past, been measured with water suspensions of a variety of wettable powder insecticides. The abrasive powers of these suspensions vary greatly, and it is therefore impossible to relate the results of one test to those of another. A standard method has been devised in which a suspension of a standard synthetic powder with a high silica content is forced through nozzles, once, at 40 lbf/in2 (2.81 kgf/cm2). The method is reliable, reproducible, and rapid, and it may also be used to evaluate the abrasiveness of water-wettable insecticide powders. Full text Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (427K), or click on a page image below to browse page by page. 937 938 939 940