Living under pressure: Lessons from the cradle of life

Deep sea alkaline hydrothermal vents have been theorized to be a place where life could have originated. The elevated temperature, alkaline pH, and unique vent action concentrate minerals and create local energetic gradients ...

Injection strategies are crucial for geothermal projects

The fear of earthquakes is one of the main reasons for reservations about geothermal energy. In order to get hot water from the depths, crevices in the rock underground often have to be created. This is done by injecting ...

Images of 'invisible' holes on cells may jumpstart research

High blood pressure, inflammation, and the sensation of pain may rely in part on tiny holes on the surface of cells, called pores. Living cells react to the environment, often by allowing water and other molecules to pass ...

Going super small to get super strong metals

You can't see them, but most of the metals around you—coins, silverware, even the steel beams holding up buildings and overpasses—are made up of tiny metal grains. Under a powerful enough microscope, you can see interlocking ...

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High pressure

High pressure science and engineering is studying the effects of high pressure on materials and the design and construction of devices, such as a diamond anvil cell, which can create high pressure. By high pressure it is usually meant pressures of thousands (kilobars) or millions (megabars) of times atmospheric pressure (about 1 bar).

It was by applying high pressure as well as high temperature to carbon that man-made diamonds were first produced as well as many other interesting discoveries. Almost any material when subjected to high pressure will compact itself into a denser form, for example, quartz, also called silica or silicon dioxide will first adopt a denser form known as coesite, then upon application of more temperature, form stishovite. These two forms of silica were first discovered by high pressure experimenters, but then found in nature at the site of a meteor impact.

Chemical bonding is likely to change under high pressure, when the P*V term in the free energy becomes comparable to the energies of typical chemical bonds - i.e. at around 100 GPa. Among the most striking changes are metallization of oxygen at 96 GPa (rendering oxygen a superconductor), and transition of sodium from a nearly-free-electron metal to a transparent insulator at ~200 GPa. At ultimately high compression, however, all materials will metallize.[citation needed]

High pressure experimentation has led to the discovery of the types of minerals which are believed to exist in the deep mantle of the Earth, such as perovskite which is thought to make up half of the Earth's bulk, and post-perovskite, which occurs at the core-mantle boundary and explains many anomalies inferred for that region.[citation needed]

Pressure "landmarks": pressure exerted by a fingernail scratching is ~0.6 GPa, typical pressures reached by large-volume presses are up to 30-40 GPa, pressures that can be generated inside diamond anvil cells are ~320 GPa, pressure in the center of the Earth is 364 GPa, highest pressures ever achieved in a shock waves are over 100,000 GPa.[citation needed]

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