Gold In A Flask
Scientists accidentally discover a new way to isolate gold that is much safer than existing processes, which use toxic cyanide.
Gold, precious forever but especially lately, is a tricky metal. Bound up in consumer electronics, jewelry and the ores that it comes from, gold is difficult to extract, and most modern processes do it with a highly toxic combination of cyanide salts. The cyanide leaches the gold out, but the cyanide can seep into the ground, causing environmental problems and posing threats to human health.
Researchers at Northwestern University recently stumbled upon a solution that uses cornstarch instead. It involves some complex chemistry, but it’s cheap, biologically friendly and nasty-ingredient-free.
Led by Sir Fraser Stoddart, a chemistry professor at Northwestern, the team discovered this method by accident when looking for something else. A postdoc named Zhichang Liu was trying to make three-dimensional cubes out of gold and starch, aiming to use them as storage containers for gases and small molecules. But a liquid mixture of dissolved gold-bromide salts and a starch-derived sugar didn’t form cubes, it formed needles. This was strange, so the team decided to try to replicate it and tested different forms of sugars.
Alpha-cyclodextrin, a cyclic starch fragment with six glucose molecules, is the best way to isolate gold, they found. “Zhichang stumbled on a piece of magic for isolating gold from anything in a green way,” Stoddart says in a statement. The spontaneous bundle of needles is made of thousands of nanowires, each 1.3 nanometers in diameter, which contain a charged gold atom inside four bromine atoms.
The interaction between the starch fragment and the gold allows the precious metal to be selectively recovered from other materials, including platinum, palladium and others. The researchers already developed a process to isolate gold from scraps, and they hope this will lead to an environmentally friendly, cheap way to recover gold from anything. The research is published in Nature Communications.
from Popular Science – New Technology, Science News, The Future Now
Scientists accidentally discover a new way to isolate gold that is much safer than existing processes, which use toxic cyanide. Gold, precious forever but especially lately, is a tricky metal.
via Pocket http://www.popsci.com/science/article/2013-05/cornstarch-replaces-cyanide-clean-new-gold-extraction-method
According to online reports, this is apparently a high school lunchroom in Seoul. A disaster of a lunchroom, that is.
According to online reports, this is apparently a high school lunchroom in Seoul. A disaster of a lunchroom, that is. The images were originally uploaded in South Korea with the title “The Worst High School” and have become a hot topic online, reports Rakuten Infoseek.
via Pocket http://kotaku.com/internet-shocked-by-koreas-school-lunch-chaos-505302121
Polaroid‘s come a long way since, well, Polaroid. Now its portfolio includes retro devices, tablets and action cameras. It’s that last category we’re interested in today, as the company just announced a new shooter, the Polaroid XS80. The credentials break down thus: HD recording in 1080p and 720p and VGA, waterproof to 30 feet, 16- 5- and 3-megapixel still modes and 120 degrees FOV. The barrel-bodied camera also includes a G sensor for auto rotation, plus anti-shake technology, a memory card slot (good for 32GB) and an HDMI socket. The price ($130 including helmet mount) puts this just below the XS100 model, but if this is just the right level of extreme for you, the good news is it’s available now.
Filed under: Cameras
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Polaroid’s come a long way since, well, Polaroid. Now its portfolio includes retro devices, tablets and action cameras. It’s that last category we’re interested in today, as the company just announced a new shooter, the Polaroid XS80.
via Pocket http://www.engadget.com/2013/05/14/polaroid-xs80-action-camera/
A new generation of engines being developed by the worldâ€™s largest jet engine maker, CFM (a partnership between GE and Snecma of France), will allow aircraft to use about 15 percent less fuelâ€”enough to save about $1 million per year per airplane and significantly reduce carbon emissions.
via Pocket http://www.technologyreview.com/news/514656/a-more-efficient-jet-engine-is-made-from-lighter-parts-some-3-d-printed/