Respiratory diseases linked with high blood pressure in lungs

Pulmonary hypertension is a type of high blood pressure that affects the lungs of both animals and people. When tiny vessels in the lungs become narrowed or blocked, it becomes harder for blood to flow through and can cause ...

Researchers synthesize 'impossible' superconductor

Researchers from the U.S., Russia, and China have bent the rules of classical chemistry and synthesized a "forbidden" compound of cerium and hydrogen—CeH9—which exhibits superconductivity at a relatively low pressure ...

Next-generation anvils for the Paris-Edinburgh cell

One of the goals of Task 7.3 of SINE2020's Sample Environment work package is to develop better high-pressure cells for neutron scattering. A cell commonly used to put a sample under high pressure is the Paris-Edinburgh (PE) ...

Researchers simulate processes prevailing in early magma oceans

The reason why the Earth's atmosphere has contained so much oxygen since about two billion years ago compared to the atmospheres of other known planets has for a long time remained a mystery. Researchers at the Bavarian Research ...

Taking evolution to heart

An international research group at UBC, Harvard University and Cardiff Metropolitan University has discovered how the human heart has adapted to support endurance physical activities. This research examines how the human ...

Significant progress made in inverse photoconductance

Valencia University (UV) researchers have modified the photoconductance of nanoparticles of tungsten oxide (WO3) in a controlled manner. This has potential applications in photonics and optomechanics. The results have been ...

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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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