Sodium battery contains solution to water desalination

Much scientific effort goes into shoring up both our energy and water supplies for the future, but what if both problems could be addressed by the same technology? Researchers at the University of Illinois have come up with a new battery design that not only relies on salt water to store and release electricity, but removes the salt ions from the water in the process.


Illinois mechanical science and engineers found they could desalinate salt water more efficiently than traditional methods relying on reverse osmosis.

Lithium-ion batteries have served us well when it comes to smartphones and laptops, but their suitability in large-scale energy storage leaves much to be desired. The relative scarcity of lithium has led scientists toward more abundant alternatives, one of which is the sodium that makes up more than 2.6 percent of the Earth’s crust. Read more

Oceanography: Dead in the water

1deadThe dead fish were one of the first signs. In July 2002, scientists with the Oregon Department of Fish and Wildlife found unusual numbers of bottom-feeding sculpin lying lifeless on the ocean floor, which would normally be teeming with life. Crabs were also dying, and they washed up onto some beaches in large numbers.

Officials at the government agency asked Francis Chan, a biogeochemist at Oregon State University in Corvallis, for help in discovering the cause of the disturbance as quickly as possible. Chan was about to set off on a scheduled research cruise along the Oregon coast, so he grabbed all the extra equipment he could think of, including a brand-new oxygen sensor.

Ocean surface waters normally contain 5–8 millilitres of oxygen per litre of water, a number that declines rapidly with depth. But on his first day out, Chan found that at a depth of 50 metres the inner coastal waters off Oregon were hypoxic — oxygen levels there were lower than 1.43 millilitres per litre, so low that fish can’t survive1.

Many regions of the world have hypoxic coastal waters, usually caused by agricultural fertilizers leaking into the ocean. The excess nutrients fuel plankton blooms, which consume oxygen. But Chan knew that the hypoxia off the Oregon shoreline must have a different cause, because that part of the coast does not have enough farming to explain it. And when his colleague Jack Barth, an oceanographer from Oregon State University, found similarly low oxygen levels farther offshore, the researchers knew that something unprecedented was happening. Read more

First comet found with ocean-like water

A recent discovery may add support to the theory that the water on Earth was brought by a rain of comets. Scientists have analyzed the comet Hartley 2, and discovered that ice found on it has the same composition as ocean water. The discovery was made utilizing an orbiting telescope on the Herschel Space Observatory, which can observe organic molecules by reading their far-infrared wavelengths.


The Herschel Space Observatory has recently analyzed the comet Hartley 2, and discovered that ice found on it has the same composition as ocean water (image by NASA).

“At the time of the Solar System formation there may have been a large reservoir of such comets with the correct ratio that bombarded the earth,” says Paul Hartogh of the Max Planck Institute for Solar System Research in Katlenburg-Lindau, Germany.

“Life would not exist on Earth without liquid water, and so the questions of how and when the oceans got here is a fundamental one,” added University of Michigan astronomy professor Ted Bergin, “It’s a big puzzle and these new findings are an important piece.” Bergin is a co-investigator on HiFi, the Heterodyne Instrument for the Infrared on the Hershel Space Observatory. Read more

Water bottle bike lock supplies security, not water

Bike locks … they’re very necessary items, but are sometimes a hassle to carry when you’re riding. U-locks can be clipped into a frame-mounted bracket, but not everyone wants a big plastic bracket permanently installed on their prized two-wheeler. They can also be stuffed in a backpack, although that can be a challenge if space in said backpack is already at a premium.


The Kuat Racks Bottle Lock is a bike lock that has the form of a water bottle.

Alternatives include a lock that you wear like a belt, and a lock that straps onto the bicycle’s top tube. Now, there’s another option – a lock that has the form of a water bottle, so it can sit in your bottle cage. Read more

Nanoscavengers could be the next-gen water purifiers

According to a joint World Health Organization/UNICEF report issued this week, an estimated 768 million people relied on unimproved drinking-water sources in 2011, with 185 million of these relying on surface water to meet their daily drinking-water needs. WHO and UNICEF have set a 2030 target for everyone to have access to a safe drinking-water supply and new water-purifying “nanoscavengers” developed by researchers at Stanford University could help achieve this goal.


New water-purifying synthetic nanoscavengers can be removed from water magnetically

There are various nanoparticles that boast different water-purifying properties. Silver nanoparticles act as an antibiotic, titanium dioxide nanoparticles trap heavy metals and pollutants, while others capture salt. Engineers call these kinds of particles nanoscavengers and in recent years they have been seeking ways to make use of them to disinfect, depollute, and desalinate contaminated water. Read more