1 Hydrogen exists as two isomers, ortho and para, based on proton nuclear spin. A temperature-dependent equilibrium dictates their ratio, with a 75% ortho isomer makeup at room temperature shifting to ...

Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States ...

Researchers are beginning to study whether the use of methylparabens and other parabens is safe. At this time, there is no conclusive evidence either way. Methylparaben is a type of paraben ...