Bright, shiny record breaker
Even on a cloudless afternoon, the seemingly unlimited energy of the Sun pales as a power source if solar cells can’t efficiently convert sunlight into electricity. In January, on a cool, clear day in New Mexico, Sandia National Laboratories and Stirling Energy Systems broke a record when 31,25 per cent of the sunlight hitting a dish made of 82 highly reflective mirrors was converted into usable power. The old record, set by Stirling in 1984, was 29,24 percent.
Two percentage points of extra power per dish could mean a lot more juice sent to the grid; Stirling recently signed an agreement to provide electricity to two California utilities that will require up to 70 000 of the new dishes.
What Nature produces in 15 minutes takes a computer 24 hours of intensive calculation to simulate – at least, that’s how long it takes for a new software model to track the growth of a single snowflake. By tweaking the variables of temperature, atmospheric pressure and water-vapour density, UC Davis and University of Wisconsin researchers can produce authentic 3D models of snowflake shapes. It’s a step forward for computational modeling and a boon to mathematicians studying the dynamics of crystal growth.
A scanner darkly
A new high-contrast X-ray technique developed by Swiss researchers promises greater accuracy in detecting hairline cracks in bones and airplane wings, and in distinguishing between healthy and cancerous tissue. Traditional X-ray machines produce an image based on how much radiation is absorbed by different materials (far left, a chicken wing), but “dark-field” images also record the radiation that scatters within an object (at left, the same wing).
While the technique has been studied in labs for several years, the Swiss team has developed a relatively inexpensive silicon grating that will allow dark-field imaging to be integrated into existing X-ray equipment in hospitals and airports.
Sticky notes get smart
People are loath to abandon familiar technology. With that in mind, a team at MIT has altered the common adhesive note, adding RFID tags (circled, at left) on each paper square so they can’t be lost. Slap a note labelled “baby pictures” on a box of old photos, and you’ll be able to find it with a keystroke. The system also stores information on a computer via digital pen, allowing mobile users to access the data with cellphones. The tech combines the comfort of paper with the powerful features of the digital age.
Catching the jets
CERN’s Large Hadron Collider (LHC) is known mainly as the accelerator that will soon begin searching for the Higgs particle in proton collisions at unprecedented energies – up to 14 TeV (14 trillion electron volts) at the ce