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Magnetic nanoparticles with ionic liquids for water purification

In many parts of the world, access to clean drinking water is far from certain. Filtration of large volumes of water, however, is slow and impractical. In the journal Angewandte Chemie, scientists have introduced a new water ...

Scientists find a place on Earth where there is no life

Living beings, especially microorganisms, have a surprising ability to adapt to the most extreme environments on Earth, but there are still places where they cannot live. European researchers have confirmed the absence of ...

'Self-cleaning' concrete could keep buildings looking new

Building materials that clean themselves could save immense time and labor in homes and businesses, as well as reduce disease risk in settings such as hospitals. Now, researchers reporting in ACS Applied Materials & Interfaces ...

NASA scientists confirm water vapor on Europa

Forty years ago, a Voyager spacecraft snapped the first closeup images of Europa, one of Jupiter's 79 moons. These revealed brownish cracks slicing the moon's icy surface, which give Europa the look of a veiny eyeball. Missions ...

Why is ice so slippery?

The answer lies in a film of water that is generated by friction, one that is far thinner than expected and much more viscous than usual water through its resemblance to the "snow cones" of crushed ice we drink during the ...

Liquid metals the secret ingredients to clean up environment

Forget the laboratory, substances that can solve environmental problems by capturing carbon dioxide, decontaminating water and cleaning up pollutants can be easily created in a kitchen, a UNSW Sydney study shows.

Could Venus have been habitable?

Venus may have been a temperate planet hosting liquid water for 2-3 billion years, until a dramatic transformation starting over 700 million years ago resurfaced around 80% of the planet. A study presented today at the EPSC-DPS ...

New insight into how much atmosphere Mars lost

A key tracer used to estimate how much atmosphere Mars lost can change depending on the time of day and the surface temperature on the Red Planet, according to new observations by NASA-funded scientists. Previous measurements ...

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Water

Water is a ubiquitous chemical substance, composed of hydrogen and oxygen, that is essential for the survival of many known forms of life. In typical usage, water refers only to its liquid form or state, but the substance also has a solid state, ice, and a gaseous state, water vapor or steam. Water covers 71% of the Earth's surface. On Earth, it is found mostly in oceans and other large water bodies, with 1.6% of water below ground in aquifers and 0.001% in the air as vapor, clouds (formed of solid and liquid water particles suspended in air), and precipitation. Saltwater oceans hold 97% of surface water, glaciers and polar ice caps 2.4%, and other land surface water such as rivers, lakes and ponds 0.6%. A very small amount of the Earth's water is contained within biological bodies and manufactured products. Other water is trapped in ice caps, glaciers, aquifers, or in lakes, sometimes providing fresh water for life on land.

Water moves continually through a cycle of evaporation or transpiration (evapotranspiration), precipitation, and runoff, usually reaching the sea. Winds carry water vapor over land at the same rate as runoff into the sea. Over land, evaporation and transpiration contribute to the precipitation over land.

Clean, fresh drinking water is essential to human and other lifeforms. Access to safe drinking water has improved steadily and substantially over the last decades in almost every part of the world. There is a clear correlation between access to safe water and GDP per capita. However, some observers have estimated that by 2025 more than half of the world population will be facing water-based vulnerability. Water plays an important role in the world economy, as it functions as a solvent for a wide variety of chemical substances and facilitates industrial cooling and transportation. Approximately 70 percent of freshwater is consumed by agriculture.

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