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September 11, 2009

Robust versus Vulnerable Roundup: Blast Resistant Glass, Electric Grid Vulnerability, Life Survives Big Asteroid

1. University of Missouri researchers are developing and testing a new type of blast-resistant glass that will be thinner, lighter and less vulnerable to small-scale explosions.



Conventional blast-resistant glass is made with laminated glass that has a plastic layer between two sheets of glass. MU researchers are now replacing the plastic layer with a transparent composite material made of glass fibers that are embedded in plastic. The glass fibers add strength because, unlike plastic, they are only about 25 microns thick, which is about half the thickness of a typical human hair, and leave little room for defects in the glass that could lead to cracking. The use of a transparent composite interlayer provides us the flexibility to change the strength of the layer by changing the glass fiber quantity and its orientation, Khanna said.

In tests, researchers are observing how the glass reacts to small-scale explosions caused by a grenade or hand-delivered bomb. They tested the glass by exploding a small bomb within close proximity of the window panel. After the blast, the glass panel was cracked but had no holes in the composite layer.

“The new multilayered transparent glass could have a wide range of potential uses if it can be made strong enough to resist small-scale explosions,” Khanna said. “The super-strong glass also may protect residential windows from hurricane winds and debris or earthquakes. Most hurricane damage occurs when windows are punctured, which allows for high-speed wind and water to enter the structure.”


2. The electric grid vulnerability study revealed: "An attack on the nodes with the lowest loads can be a more effective way to destroy the electrical power grid of the western US due to cascading failures," Wang says. To minimise the risk, he says, the grid's operators should defend the west coast sections by adjusting their power capacity to ensure these specific conditions do not arise.

The US Department of Homeland Security is reviewing the research, says John Verrico, the department's technology spokesman, who adds that countermeasures are already in the works. "Our engineers are working on a self-limiting, high-temperature superconductor technology which would stop and prevent power surges generated anywhere in the system from spreading to other substations. Pilot tests in New York City may be ready as soon as 2010."

Al Fin notes that simply removed the anchoring bolts for the line tower can cause a blackout

Foresight Institute also wrote about the many ways to take out transformers.

EMP isn’t the only way to fry a transformer. Natural solar Carrington events would have the same effect. They could be blown up the old-fashioned way by explosives — or even explosively shorted out by shooting giant steel arrows into them from catapults.

Rob Freitas and J Storrs Hall once did a back-of-the-envelope calculation that a fully-developed molecular manufacturing capability could rebuild the entire infrastructure of the US in somewhere between 1 and 2 weeks. If you have that kind of productive capacity available, you can stand lots of shocks with equanimity. If the twin towers had that kind of productive technology built in for active maintenance, repair, and expansion, they’d still be standing.




3. How life survives and asteroid impact

A dinosaur-killing asteroid may have wiped out much of life on Earth 65 million years ago, but now scientists have discovered how smaller organisms might have survived in the darkness following such a catastrophic impact.

They tested both freshwater and ocean mixotrophs under conditions ranging from low light to complete darkness for six months, and added food sources during short-term experiments to simulate decaying organic matter. Mixotrophs survived all the experiments, and some even grew under the low light conditions. Their ability to consume other organisms or organic matter helped them rebound quickly after low light returned, perhaps similar to the clouds of dust and debris finally beginning to clear.

But the real shock came from how well light-dependent organisms did when living with the mixotrophs. No photosynthesis could take place under the complete darkness, but the phototrophs mostly managed to survive based on nutrients cycled by the active mixotrophs.

"We were extremely surprised at how well phototrophs did during six months darkness, when they can't eat at all," Jones said. Such findings may cause researchers to rethink how well certain life forms survived the catastrophic impacts that dot Earth's geological record.

Furthermore, the mixotroph activity allowed the phototroph populations to rebound quickly back to normal within a month. And in the end, both mixotrophs and phototrophs tended to fare better when living together.

"So long as mixotrophs are cycling nutrients, [phototroph] algae can take off quickly and get the life cycle going," Jones explained.


4. Health officials say influenza is circulating unusually early this year with cases in every state - and nearly all the infections are swine flu.

Australian and U.S. researchers said Thursday that one dose of the new swine flu vaccine looks strong enough to protect adults - and can begin protection within 10 days of the shot.

Australian drug maker CSL Ltd. published results of a study that found 75 percent to 96 percent of vaccinated people should be protected with a single dose - the same degree of effectiveness as the regular winter flu shot. That's remarkable considering scientists thought it would take two doses.



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