Archive for August, 2008
Exploring the function of sleep
Wednesday, August 27th, 2008
Is sleep essential?
Weeding Out Your Worries
Tuesday, August 26th, 2008Brain study could lead to new understanding of depression
Tuesday, August 26th, 2008
Brain scientists have moved a step closer to understanding why some people may be more prone to depression than others.
Blinking liars!
Monday, August 25th, 2008
Monitoring the speed at which someone blinks could be enough to give away whether they are lying or not.
Cocaine: How addiction develops
Monday, August 25th, 2008
Using genetic engineering, researchers have now been able to selectively switch off those protein components in dopamine-producing neurons that are integrated into the receptor complexes under the influence of cocaine.
Aboriginal kids can count without numbers
Sunday, August 24th, 2008
Knowing the words for numbers is not necessary to be able to count
Complex decisions? Don’t sleep on it
Sunday, August 24th, 2008
Neither snap judgments nor sleeping on a problem are any better than conscious thinking for making complex decisions
Researchers link cocoa flavanols to improved brain blood flow
Saturday, August 23rd, 2008
New study suggests cocoa compounds could hold promise for stroke
Killer carbs – Scientist finds the key to overeating as we age
Saturday, August 23rd, 2008
A Monash University scientist has discovered key appetite control cells in the human brain degenerate over time, causing increased hunger and potentially weight-gain as we grow older.
Flat-panel ion thrusters
Friday, August 22nd, 2008
You may think spacecraft thrusters need to be big and powerful, but Brian Gilchrist and colleagues at the University of Michigan in Ann Arbor, are thinking small. They propose that tiny "nano thrusters" could be made into flat sheets mounted on the side of spacecraft.
Conventional ion thrusters used for manoeuvring vehicles in space are roughly fridge-sized and work by accelerating gas ions to generate force in the opposite direction. But they waste a lot of gas and are limited in lifetime because the accelerated ions damage the engine.
Their nanothrusters, say the Michigan team, get around these problems. Each consists of a small chamber of fluid with electrodes inside and a vent at the top. Above that vent more electrodes generate a powerful electric field.
The fluid contains nanoparticles just tens of nanometres across that are ionised by electrodes in the chamber. Those charged ions are accelerated by the electric field and ejected from the vent, producing thrust.
These nanothrusters can be used in large numbers on flat panels with micro-scale fuel delivery channels. The panels would cover large areas of spacecraft and in the drag-free space environment give all vehicles fine and efficient control.
The inventors hope the flat-panel thrusters will reduce the cost of spacecraft thanks to their efficiency and light weight, cutting the cost of launching vehicles into space.
Read the full flat panel ion thruster patent.
Justin Mullins, New Scientist consultant
Conventional ion thrusters used for manoeuvring vehicles in space are roughly fridge-sized and work by accelerating gas ions to generate force in the opposite direction. But they waste a lot of gas and are limited in lifetime because the accelerated ions damage the engine.
Their nanothrusters, say the Michigan team, get around these problems. Each consists of a small chamber of fluid with electrodes inside and a vent at the top. Above that vent more electrodes generate a powerful electric field.
The fluid contains nanoparticles just tens of nanometres across that are ionised by electrodes in the chamber. Those charged ions are accelerated by the electric field and ejected from the vent, producing thrust.
These nanothrusters can be used in large numbers on flat panels with micro-scale fuel delivery channels. The panels would cover large areas of spacecraft and in the drag-free space environment give all vehicles fine and efficient control.
The inventors hope the flat-panel thrusters will reduce the cost of spacecraft thanks to their efficiency and light weight, cutting the cost of launching vehicles into space.
Read the full flat panel ion thruster patent.
Justin Mullins, New Scientist consultant