relief gases
111tunnels and underground excavations — ▪ engineering Introduction Great tunnels of the world Great tunnels of the worldhorizontal underground passageway produced by excavation or occasionally by nature s action in dissolving a soluble rock, such as limestone. A vertical opening …
112Volcanism on Mars — Mariner 9 image of Olympus Mons[1]. This is one of the first images to show that Mars has large volcanoes. Volcanic activity, or volcanism, has played a significant role in the geologic evolution of Mars.[ …
113Historia del motor de combustión interna — Prototipo de motor presentado por Karl Benz en su solicitud de patente de un automóvil el 29 de junio de 1886. Los orígenes de los motores son muy remotos. Especialmente si se consideran los inicios o precededents de algunos elementos… …
114Mountain — For other uses, see Mountain (disambiguation). Chimborazo …
115Ganymede (moon) — Ganymede Image of Ganymede s anti Jovian hemisphere taken by the Galileo probe. Lighter surfaces, such as in recent impacts, grooved terrain and the whitish north polar cap at upper right, are enriched in water ice. Discovery …
116Chronic obstructive pulmonary disease — Classification and external resources Gross pathology of a lung showing centrilobular type emphysema characteristic of smoking. This close up of the fixed, cut lung surface shows multiple cavit …
117Poppet valve — A poppet valve is a valve consisting of a hole, usually round or oval, and a tapered plug, usually a disk shape on the end of a shaft also called a valve stem. The shaft guides the plug portion by sliding through a valve guide. In most… …
118Firestorm — A firestorm is a conflagration which attains such intensity that it creates and sustains its own wind system. It is most commonly a natural phenomenon, created during some of the largest bushfires, forest fires, and wildfires. The Great Peshtigo… …
119Domestic policy of the George W. Bush administration — President George W. Bush signs into law S.2590, the Federal Funding Accountability and Transparency Act of 2006 in the Dwight D. Eisenhower Executive Office Building. Looking on are Sen. Susan Collins (R ME), Chairwoman of the Senate Homeland… …
120Metering pump — A metering pump is a pump used to pump liquids at adjustable flow rates which are precise when averaged over time. Delivery of fluids in precise adjustable flow rates is sometimes called metering. The term metering pump is based on the… …
