Abstract: In the last 3000 yr, one significant and rapid increase in the concentration of 14C in tree rings was observed; it corresponds to a gamma-ray energy input of 7x10^24 erg at Earth within up to one year in AD 774/5 (Miyake et al. 2012).
Linked to the discussion we had last week on elastically non-linear polymers. The inverted liquid->solid phase transition might be interesting and the material might be self-healing just above the transition.
Small scale laser induced electron accelerator followed by induced beta decay to produce positrons. Relatively simple, yet requires a high power fs laser and some precision engineering
The Forest Products Laboratory of the US Forest Service has opened a US$1.7 million pilot plant for the production of cellulose nanocrystals (CNC) from wood by-products materials such as wood chips and sawdust. Prepared properly, CNCs are stronger and stiffer than Kevlar or carbon fibers, so that putting CNC into composite materials results in high strength, low weight products.
The Rayleigh criterion specifies the minimum separation between two incoherent point sources that may be resolved into distinct objects. Here, a strategy to break the limits of this criterion for the first time, some small allusion to telescopic systems.
"Hbar Technologies plans a Kickstarter effort to raise US $200,000 for the next phase design of an antimatter-propelled spaceship. The two scientists behind this design effort are a veteran Fermilab particle accelerator scientist and a former Los Alamos National Laboratory physicist and founding director of the U.S. Center for Space Nuclear Research. They originally developed it for NASA at the turn of the millennium."