P: Pachymeter Polymerization

pachymeter

An instrument for measuring the thickness of material such as paper.

pack

1. In data processing, a method for condensing data in order to increase storage capacity. 2. A remov-able disk.

packaged boiler

A packaged steam or hotwater firetube boiler is a modified Scotch unit that is engineered, built, and fire-tested before shipment. Its material, workmanship, and performance are guaranteed by manufacturer as stated in its standard conditions of sale. The components of a packaged boiler include, but are not limited to, the burner, boiler, and controls.

packaged steam generator

See packaged boiler.

packed column

A distillation column that is filled with packing (commonly Raschig rings) on order to mix the descending liquid with the ascending vapors. Packing is often used instead of trays in the columns used for certain applications (such as gas adsorption) or for very low pressure-drop systems.

packed decimal

A method of representing a decimal number by storing a pair of decimal digits in one eight-bit byte. This method takes advantage of the fact that the numbers zero through nine can be represented by four bits.

packet

1. A group of bits, which includes the data and control elements, that are switched and transmitted as a whole. 2. The unit of data that is transmitted across a packetswitched network.

See also block.

packet access device (PAD)

An interface between a terminal or computer and a packet-switching network.

packet switching

A data transmission technique whereby the physical resources on a path are switched on...