BACKGROUND: A review of the literature showed that the core competencies needed by newly graduated Chinese nurses were not as of yet undocumented. OBJECTIVE: To develop a psychometrically sound instrument for identifying and measuring the core competencies needed by Chinese nursing baccalaureate graduates.
A&P here. Zinc chromate is used as a primer on aluminum surfaces as a conversion process to inhibit corrosion. Since nearly all modern aircraft skins and structures are made from aluminum, this compound and its derivatives are the most common primers seen in aircraft manufacturing.
Self etch primer is for metal that has not been etched by some other means. So if you are building a something and weld up some brand new sheets of the steel and do not want to sand them you use the self etch primer. The job of self etch primer is to make a good surface for putting the next layer of paint on to the metal. If the metal is already a good surface for a direct to metal paint then you do not need (and do not want) an etching primer. The etch primer has been improperly thought of as a way to prevent corrosion.