Reaction cell, atomic hydrogen-carbon

Figure 1. Schematic arrangement of atomic hydrogen-carbon reaction cell...

On the first stage of hydrogenation reaction the C/H composition of fulleranes can be approximately determined by XRD from increase of unit cell parameter. The crystal structure of fulleranes powder remains to be fee like in pristine C60 but the cell parameter increases proportionally to the number of attached hydrogen atoms due to increase of van der Waals diameter of molecules. Using chemical analysis on carbon/hydrogen ratio performed on samples hydrogenated at various conditions we constructed the dependence which could be used for approximate evaluation of hydrogen content from known cell parameter determined from powder XRD, see Fig. 5.3... 

In aerobic cells, polyunsaturated fatty acids of membrane phospholipids easily undergo such oxidative chain reactions [111,112]. This is because the double bonds of the polyunsaturated structure are repeatedly connected to each other by c/s-methylene units. Such bis-allylic structures enable electron delocalization on five carbon atoms, making the initial hydrogen abstraction on... 

The first step in de novo fatty acid synthesis is the production of malonyl-CoA from acetyl-CoA and bicarbonate. This committed step is catalyzed by acetyl-CoA carboxylase present in the cytoplasm of liver cells and adipocytes. After replacement of the CoA residue in acetyl-CoA by ACP (acyl carrier protein), malonyl-ACP is used to convert acetyl-ACP to butyryl-ACP by the fatty acid synthase complex. In this multistep reaction, NADPH is used as donor of hydrogen atoms and CO2 is produced. Butyryl-ACP is subsequently elongated to hexanoyl-ACP by a similar process in which malonyl-ACP serves as donor of two carbon atoms required for lengthening of the growing acyl chain. This process is repeated until palmitic acid... 

Figure 1. (a) Cell arrangement for metal hydride hydrogen insertion reaction. Left side, acid reduction and hydrogen atom incorporation in palladium (Pd) foil membrane. Right side, electrostatic field for enhancement of carbon dioxide/bicarbonate adsorption on foil membrane, (b.) Blow-up of palladium/hydride foil showing hydrogen insertion into carbon dioxide. 

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