About 22% of the energy used in the U.S. comes from natural gas. There are about 300,000 miles of natural gas pipelines in the lower 48 states and 425,000 gas producing wells. The history of natural gas.
thru-hole. A circuit board packaging technique in which the leads (pins) on discrete components and chips are inserted through holes in the printed circuit board and soldered from beneath.
a hole or break in the containing walls or membranes of an organ or structure of the body. Perforation occurs when erosion, infection, or other factors create a weak spot in the organ and internal pressure causes a rupture. It also may result from a deep penetrating wound caused by trauma.