A New Synthetic Compound Can Neutralize Chemical Weapons in Minutes
Chemical weapons are a dangerous and all-to-real threat. Now, a team of scientists has
developed a new compound that can deactivate chemical weapons—including nerve agents like sarin—in just minutes.
A team from Northwestern University in Evanston, Illinois, have found inspiration for the new compound in enzymes called phosphotriesterases. Usually produced by bacteria, these proteins deactivate some pesticides—and nerves gases—in milliseconds. Problem is, those enzymes can break down easily, losing their ability to halt the actions of the dangerous compounds.
So the researchers attempted to reproduce the same effects using a synthetic catalyst. Science
describes nicely how they went about the process:
They started with metal-organic frameworks (MOFs), a recently developed class of porous compounds composed of metals arranged in a crystalline network linked by carbon-based molecules. MOFs are highly adaptable materials... and because MOFs are porous, they have large surface areas that can rapidly create chemical bonds, making them good candidates for catalysts.
In the natural enzyme, phosphotriesterase, two zinc atoms act as so-called Lewis acids, which accept electrons to bind with the nerve agent. Once the agent has bonded, hydrolysis occurs—a water molecule attacks the agent, slicing and dicing essential chemical bonds, thereby deactivating it. The scientists designed a MOF with a similar structure, but they replaced the zinc with zirconium, which likewise behaves as a Lewis acid and makes for an ultrastable MOF.
In tests
published in Nature Materials, the team used their catalyst to deactivate a pesticide similar to nerve agents but safer to use in the lab. Experiments showed that the new compounds—known as NU-1000—deactivated half of the pesticide in 15 minutes. Further testing by U.S army facilities has shown that it neutralizes half of the nerve agent GD—more toxic than the well-known sarin—in just three minutes. The researchers claim that that's 80 times faster than any previous compound has managed.
It's still not perfect, though. Indeed, the natural version—though fragile—works up to 100,000 times faster, so the team certainly has some way to go before it's as good as nature itself. But for now, it's a significant milestone in the quest to keep the world safe from chemical warfare.
This Is the World’s Highest Peak-Power Laser Diode Array
Researchers at the Lawrence Livermore National Laboratory
have created the world's highest peak-power laser diode array, capable of creating up to 3.2 megawatts. The new device will be used in Europe's new Extreme Light facility, which will be as bad-*** as it sounds.
The diode array will sit within the High-Repetition-Rate Advanced Petawatt Laser System at the European Union's Extreme Light Infrastructure Beamlines facility, which is being built in the Czech Republic. The new array is designed as a replacement for flashlamps, which are currently used as the primary light source for laser sources in extreme light testing facilities. Flashlamp installations typically create light pulses once per second; the new array can fire 10 times per second, sending out kilojoule laser pulses each time. Andy Bayramian, one of the researchers working on the project, explains:
"Flashlamp technology for lasers has been around for more than 50 years, and we've pretty much pushed the limits of that technology and maxed out what we can do with them. We've closed the books on flashlamps and started a new one with these laser diode arrays, enabling a far more advanced class of high-energy laser systems."
The new array uses a pulsed-power system that draws electricity from the grid and then converts it into "extremely high-current, precisely shaped electrical pulses." By high current, they mean a staggering 40,000 amps. The complete High-Repetition-Rate Advanced Petawatt Laser System will produce laser pulses with powers greater than one petawatt at a repetition rate of 10 Hertz, with each pulse lasting 30 femtoseconds. It should be up and running by 2017.
New Liquid 3D Printing System Is 25 Times Faster Than Its Competitors
3D printing isn't short of advocates in the design and engineering world, because of its ability to easily produce prototypes—but it can be slow. A new company called
Carbon3D hopes to change that, though, with a new 3D printing method that claims to be 25-100 times faster than other resin printing techniques.
The start-up has just emerged from stealth,
3Dprint reports, announcing its new technique called Continuous Liquid Interface Production. CLIP seems to build on an existing 3D printing technique which uses photosensitive resin and a laser to cure it into a solid. But unlike similar techniques, which perform that process layer-by-layer, CLIP uses laser light to cure along with oxygen to inhibit the process—allowing it to actually print in 3 dimensions at once.
The printer uses a transparent and oxygen-permeable window, which allows it to control the amount of oxygen and laser light incident on the liquid resin. Its makers claim that the printer offers such fine control over oxygen exposure that it it can be used to create spots that won't be cured as small as tens of microns thick. Meanwhile, the laser can zip across the surface, curing spots that aren't exposed to oxygen. You can see it in action below.
Exact details of how they achieve all this remain under wraps—at least to most of us. But Carbon3D has told at least some people about how the technology works, because its managed to secure a cool $41 million in funding to date from venture capital firms.
Printing at such swift rates is clearly incredibly desirable. If CLIP can be turned into a commercial product it could take 3D printing from prototyping niche to something that's genuinely useful in everyday manufacturing. And that's exactly what 3D printing is waiting for.