During process operations that involve handling powders - either as raw materials, intermediate ingredients or finished products the ability to control particle size can make the difference between troublesome and trouble-free operation. Particle size impacts such things as powder flow, reactivity and film homogeneity, and control of particle size has a direct impact on how a powder behaves during processing. This article discusses the advantages of airbased classifiers for this task.

The development of procedures and equipment to protect personnel who handle toxic or high-potency compounds is a two-step process. First, the level of controls required must be established; then the methods to achieve such control must be determined and implemented. This report discusses ways in which workers can protect themselves; Part 2, scheduled to appear next month, discusses the specialized equipment that is available to handle potent compounds safely.

A dielectric debate polarizes chipmakers. Debate rages among semiconductor fabricators, with some chemical processors turning out spinon dielectrics and others favoring silica films for chemical vapor deposition.