the natural beauty of attractive and repulsive light

Image Credit: Hong Tang and Yale University.

Scientist Hong Yang at Yale University has proven the ability to "manipulate circuits on silicon board with attractive light" and has now done the same with repulsive light. The technology splits a beam of infrared light down two nano-wires which then causes the silicon chips to move perpindicular to the direction of the light and nano-wires. The ability to control these components in both directions now means that they have complete control over an object -- though at an incredibly small scale -- through the use of light alone. Says Yang, "We've demonstrated that these are tunable forces we can engineer." Small as it may seem, this is an incredible breakthrough considering the ability to engineer functional technology powered by the physical force of light is possible. Photosythesis is the naturally occuring process that allows plants, algea, and bacteria to use sunlight to process carbon dioxide into natural energy-providing elements. Considered as a sustaining source of all carbon-based lifeforms on Earth, photosynthesis -- the conversion of light into energy -- can be viewed as a fundamental condition for "life". Yang's findings may lay the foundation for "living" materials that function and exist indefinately under the power light.


"Photosystem: A light-harvesting cluster of photosynthetic pigments present in the thylakoid membrane of chloroplasts." via Wikipedia.

Seen on i09 and Physics.org.

16,000 year-old concrete

photo by chris bobko
Engineer's at MIT have discovered the cause behind concrete to deform and weaken over time due to stress. called concrete creep, a rearrangement of structure at the nano-scale, professor Franz-Jozef Ulm's paper suggests that, if slowed by 2.6%, the result would increase the effective lifespan of concrete up to 16,000 years. Although I understand BLDGBLG's hesitation at a material synonnomous with parking structures being able to last for 16,000 years, there may be practical uses for this. Aside from the ecological benefit of only producing the concrete once, extended-use infrastrcutre such as bridges and foundations would require less maintanence and replacement over the material life-cycle. Also, by micro-engineering the material, a complete re-imagining of construction methods with the material is possible. Working at a nano-scale it becomes possible to engineer into the concrete certain nano-structures or formulas that would allow for easy assembly/disassembly and manipulation. If the material does indeed have such durability, the ability to re-engineer that actual piece of concrete, whether to repair or reform, could yield infinite solutions. Ironically, the material that defined 'modularity' could be re-engineered to be modular at a molecular level. Could actual 'curable' concrete be created where the atomic structure is re-energized and given a molecular tune-up? A structural member is tested and the calculations reveal it's structure has decomposed to an unsafe level. A specific electrical current is applied to the material and particles are jostled back into place and the original strength is again realized.