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Ocean water may reach upper mantle through deep sea faults

Scientists at the University of Liverpool have shown that deep sea fault zones could transport much larger amounts of water from Earth’s oceans to the upper mantle than previously thought.

Parinacota, a volcano on the border of Chile and Bolivia.

Parinacota, a volcano on the border of Chile and Bolivia.

Water is carried mantle by deep sea fault zones which penetrate the oceanic plate as it bends into the subduction zone. Subduction, where an oceanic tectonic plate is forced beneath another plate, causes large earthquakes such as the recent Tohoku earthquake, as well as many earthquakes that occur hundreds of kilometers below Earth’s surface. Read more

Water makes wires even more nano

Water is the key component in a Rice University process to reliably create patterns of metallic and semiconducting wires less than 10 nanometers wide.

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These nanowires were created at Rice University through a process called meniscus-mask lithography. From left, they’re made of silicon, silicon dioxide, gold, chromium, tungsten, titanium, titanium dioxide and aluminum. The scale bar is 1 micron for all images.

The technique by the Rice lab of chemist James Tour builds upon its discovery that the meniscus — the curvy surface of water at its edge — can be an effective mask to make nanowires.

The Rice team of Tour and graduate students Vera Abramova and Alexander Slesarev have now made nanowires between 6 and 16 nanometers wide from silicon, silicon dioxide, gold, chromium, tungsten, titanium, titanium dioxide and aluminum. They have also made crossbar structures of conducting nanowires from one or more of the materials. Read more

Mars might have salty liquid water

Researchers have long known that there was water in the form of ice on Mars. Now, new research from NASA’s Mars rover Curiosity shows that it is possible that there is liquid water close to the surface of Mars. The explanation is that the substance perchlorate has been found in the soil, which lowers the freezing point so the water does not freeze into ice, but is liquid and present in very salty salt water — a brine. The results are published in the scientific journal Nature.

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The researchers believe that Gale Crater was a large lake between 3.5 and 2.7 billion years ago. Mount Sharp, which is now an approximately five kilometer tall mountain in the middle of the crater, was probably formed by deposits from the crater and the surrounding area.

“We have discovered the substance calcium perchlorate in the soil and, under the right conditions, it absorbs water vapour from the atmosphere. Our measurements from the Curiosity rover’s weather monitoring station show that these conditions exist at night and just after sunrise in the winter. Based on measurements of humidity and the temperature at a height of 1.6 meters and at the surface of the planet, we can estimate the amount of water that is absorbed. Read more

Water splitter runs on an ordinary AAA battery

Hongjie Dai and colleagues have developed a cheap, emissions-free device that uses a 1.5-volt battery to split water into hydrogen and oxygen. The hydrogen gas could be used to power fuel cells in zero-emissions vehicles.

Water-AAA-battery

Stanford scientists have developed a low-cost device that uses an ordinary AAA battery to split water into oxygen and hydrogen gas. Gas bubbles are produced from electrodes made of inexpensive nickel and iron.

Stanford University Professor Hongjie Dai has developed an emissions-free electrolytic device that splits water into hydrogen and oxygen at room temperature.

In 2015, American consumers will finally be able to purchase fuel cell cars from Toyota and other manufacturers. Although touted as zero-emissions vehicles, most of the cars will run on hydrogen made from natural gas, a fossil fuel that contributes to global warming. Read more

Water, water, everywhere: Controlling the properties of nanomaterials

Scientists at the US Department of Energy’s Oak Ridge National Laboratory are learning how the properties of water molecules on the surface of metal oxides can be used to better control these minerals and use them to make products such as more efficient semiconductors for organic light emitting diodes and solar cells, safer vehicle glass in fog and frost, and more environmentally friendly chemical sensors for industrial applications.

Water-nanomaterials

Pictured at the NOMAD instrument at Oak Ridge National Laboratory’s Spallation Neutron Source are David Wesolowski of the Chemical Sciences Division, Thomas Proffen of SNS, Hsiu-Wen Wang of JINS, and NOMAD instrument scientist Mikhail Feygenson. Wang and Feygenson are holding the NOMAD sample-mounting wand.

The behavior of water at the surface of a mineral is determined largely by the ordered array of atoms in that area, called the interfacial region. However, when the particles of the mineral or of any crystalline solid are nanometer-sized, interfacial water can alter the crystalline structure of the particles, control interactions between particles that cause them to aggregate, or strongly encapsulate the particles, which allows them to persist for long periods in the environment. As water is an abundant component of our atmosphere, it is usually present on nanoparticle surfaces exposed to air. Read more