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An electron donating group (EDG) or electron releasing group (ERG, Z in structural formulas) is an atom or functional group that donates some of its electron density into a conjugated π system via resonance (mesomerism) or inductive effects (or induction)—called +M or +I effects, respectively—thus making the π system more nucleophilic.
Delocalizing the radical ion stabilizes the transition state structure. As a result, the energy of activation decreases, enhancing the rate of the overall reaction. According to the captodative effect, the rate of a reaction is the greatest when both the EDG and EWG are able to delocalize the radical ion in the transition state structure. [7]
An electron-withdrawing group (EWG) is a group or atom that has the ability to draw electron density toward itself and away from other adjacent atoms. [1] This electron density transfer is often achieved by resonance or inductive effects.
You may be familiar with the Environmental Working Group (EWG) because they release a list of the most pesticide-filled produce every year called The Dirty Dozen. They also establish the produce ...
EDG may refer to: Science and medicine. Electron donating group, a category in chemistry; Electrodermograph, a measuring device for skin;
Life expectancy development in some big countries of the world since 1960 Life expectancy at birth, measured by region, between 1950 and 2050 Life expectancy by world region, from 1770 to 2018 Human life expectancy is a statistical measure of the estimate of the average remaining years of life at a given age.
Animals also vary in the degree of coupling between oxidative phosphorylation and ATP production, the amount of saturated fat in mitochondrial membranes, the amount of DNA repair, and many other factors that affect maximum life span. [9] Furthermore, a number of species with high metabolic rate, like bats and birds, are long-lived.
A mutation in the age−1 gene of the nematode worm Caenorhabditis elegans increased mean life span 65% and maximum life span 110%. [82] However, the degree of lifespan extension in relative terms by both the age-1 and daf-2 mutations is strongly dependent on ambient temperature, with ≈10% extension at 16 °C and 65% extension at 27 °C.