Single-contact electrification apparatus measures charge transfer from one controlled particle-surface or particle-particle contact, isolating a variable that bulk triboelectric and charge decay measurements can only report as an average.

As aerospace metal additive manufacturing capacity expands, more reused powder is going back into qualified builds. The virgin-to-reused blend ratio decision depends on PSD shift, satellite formation, and morphology drift, and cannot be settled by a single powder check disconnected from the part's stress state.

Two lots that pass the same incoming flowability spec can still granulate differently after roller compaction. The reason usually traces to ribbon density, which responds to roll force, gap width, and feed screw speed as an interacting set, not to roll pressure in isolation.

Dense-phase and dilute-phase pneumatic conveying create different particle contact mechanics, and the resulting attrition and segregation risk depends on velocity, solids loading ratio, and the powder's own attrition sensitivity, not on a fixed assumption about which mode is gentler.