Applied Physics

A team of researchers is seeking to determine if an ingredient found in shrimp and lobster shells might make future missions to Mars safer for space crews who could be injured along the way.

Scientists from Harvey Mudd College (HMC) in California and the University of Louisville are collaborating with bioengineering and biomaterials company BioSTAR West on research efforts to better understand how to treat injuries aboard long space flights. This effort is directed and led by Hawaii Chitopure Inc., a Honolulu based biomaterials company specializing in the U.S. manufacture of ultra-pure chitosan, a polymer developed from the shells of crustaceans, such as lobsters, crabs, and shrimp. The team has developed experiments using chitosan, which has recently gained approval in the U.S.

The emergence of nanotechnology brings with it the opportunity to manipulate materials at practically the molecular level. So, could a nanotech computer be built?

Robert Blick and colleagues in the department of Electrical & Computer Engineering at the University of Wisconsin-Madison think so. They propose a new type of electromechanical computer built from components a millionth the thickness of the human hair.

Mechanical? Before silicon chips or even transistors there were fictional dreams of levers, ratchets and cogs, complete with brass fittings that could solve mysteriers.

In an advance that could help curb global demand for oil, MIT researchers have demonstrated how ordinary spark-ignition automobile engines can, under certain driving conditions, move into a spark-free operating mode that is more fuel-efficient and just as clean.

The mode-switching capability could appear in production models within a few years, improving fuel economy by several miles per gallon in millions of new cars each year. Over time, that change could cut oil demand in the United States alone by a million barrels a day. Currently, the U.S. consumes more than 20 million barrels of oil a day.

Many researchers are studying a new way of operating an internal combustion engine known as “homogeneous charge compression ignition” (HCCI).

What do sand, coal, cereal, ice cubes, marbles, gravel, sugar, pills, and powders have in common" They are all granular materials, members of an unruly family of substances that refuse to completely conform to the laws of behavior for either solids or liquids—much to the consternation of theoretical physicists and manufacturers alike. Whether it’s a huge grain silo, a coal hopper or a pharmaceutical manufacturing plant, being able to predict the behavior of dense granular packings subjected to different external stresses is key to keeping things from jamming up or collapsing.

Improved sensing and detection to combat terrorism has brought the need for advanced defense technologies to the forefront and laser-based defense systems are now being designed for this need, including the use of infrared countermeasures to protect aircraft from heat-seeking missiles and highly sensitive chemical detectors for reliable early detection of trace explosives and other toxins at a safe distance for personnel.

Since practical systems must be easily portable by a soldier, aircraft or unmanned vehicle, they must be lightweight, compact and power efficient. In addition, such systems also would need to be widely deployable and available to all soldiers, airplanes and public facilities, which requires a low production and operating cost.

“It’s an amazing little marvel,” said Heinrich Jaeger, Professor in Physics at the University of Chicago. “This is not a very fragile layer, but rather a robust, resilient membrane.”

Even when suspended over a tiny hole and poked with an ultrafine tip, the membrane boasts the equivalent strength of an ultrathin sheet of plexiglass that maintains its structural integrity at relatively high temperatures.

A new National Science Foundation (NSF) report finds the number of U.S. science and engineering (S&E) articles in major peer-reviewed journals flattened in the 1990s, after more than two decades of growth, but U.S. influence in world science and technology remains strong.

The report, Changing U.S. Output of Scientific Articles: 1988 - 2003, finds changes occurred despite continued increases in funding and personnel for research and development. Flattening occurred in nearly all U.S. research disciplines and types of institutions.

In contrast, emerging Asian nations had large increases in publication numbers, reflecting their growing expertise in science and technology. European Union totals also went up.

A catastrophic megaflood separated Britain from France hundreds of thousands of years ago, changing the course of British history, according to research led by Sanjeev Gupta and Jenny Collier from Imperial College London, has revealed spectacular images of a huge valley tens of kilometres wide and up to 50 metres deep carved into chalk bedrock on the floor of the English Channel.

Using high-resolution sonar waves the team captured images of a perfectly preserved submerged world in the channel basin. The maps highlight deep scour marks and landforms which were created by torrents of water rushing over the exposed channel basin.

To the north of the channel basin was a lake which formed in the area now known as the southern North Sea.

Engineers at the University of Pennsylvania have taken a step toward simplifying the creation of nanostructures by identifying the first inorganic material to phase separate with near-perfect order at the nanometer scale.

The finding provides an atomically tuneable nanocomposite “workbench” that is cheap and easy to produce and provides a super-lattice foundation potentially suitable for building nanostructures.

Alerted by an unusual diffraction effect of a common ceramic material, researchers used imaging to identify a two-phase structural pattern ideal as the first step towards nanodevice construction.

A new method which will allow more effective voice discrimination has been developed by researchers at the University of Hertfordshire.

Dr Aladdin Ariyaeeinia at the University’s School of Electronic Communication & Electrical Engineering and his team have been conducting research into voice biometrics (speaker recognition) for over 10 years. The process has various potential applications such as verifying individuals’ identities when they try to access cash machines or try to bank or shop online.

The team’s most recent development is a new approach to speaker change detection, a process which captures when speakers change in a given conversational audio stream which could have very useful applications in criminal investigations and in managing audio-visual recordings.