The quantum-classical transition of methyl rotation highlights conflicting assumptions of quan­ tum and classical mechanics, the first assuming that identical fermions are indistinguishable while the second recognises they are distinguishable through their histories. When this is introduced into quantum mechanics, the two are compatible and there is a smooth transition of the methyl rotational ...

Low field methyl tunnelling spectra of dimethyl sulphide have been measured using field cycling NMR and indicate the existence of two distinct methyl groups with tunnel. frequencies of 100kHz and 750kHz. Spectra show a significant broadening of the Larmor peak at those fields at which the Larmor and tunnel frequencies are equal. These are resonances between the rotational and spin dynamics of t...

the fruit of melia azedarach l. (meliaceae) was extracted with hexane, and its fatty acids methyl ester was analyzed using gc/ms. thirteen components representing 85.1% of the total extract were identified. the major components identified were methyl palmitate (18.8%), methyl linolenate (16.1%) and methyl linoleate (9.8%). the fruits’ extract had a lc50 of 5.5 ppm against the larvae of anophles...