In light of the results of synthetic organic chemistry and the ability of molecular machines to make reactions site specific, it seems difficult to maintain that nonprotein machine components can not be built and assembled. (imm.org)
Regardless, the result is a satisfying full - circuit ride for Solomon, who in 1986 led the study that first identified stratospheric clouds as the chlorine reaction sites, and who played important roles in the scientific assessments for the Montreal Protocol and subsequent status reports. (sciencemag.org)
The most important breakthrough, says Fréchet, has been to make dual reaction sites that are self - generating as the structure grows, so the process is a chain reaction. (newscientist.com)