Abstract: A process is provided for the electrochemical generation of N.sub.2 O.sub.5 in HNO.sub.3, whereby a solution of N.sub.2 O.sub.4 in HNO.sub.3 is electrolyzed. An electrolytic cell for the electrolysis is also provided, having substantially parallel electrodes in electrode compartments separated by a cell membrane. The anode is of Pt, Nb, Nb/Ta 40:60 alloy with a Pt coating. The cathode is Pt, stainless steel, Nb, Nb/Ta 40:60 alloy. The cell membrane is preferably a perfluorinated cationic exchange membrane. In use N.sub.2 O.sub.5 forms in the anolyte and N.sub.2 O.sub.4 increases in the catholyte. A suitable design of cell and its use in a single- or multi-stage electrolysis process is also described.

Abstract: An aid for teaching a golfer how to position his feet correctly when executing a drive, comprises a base having two relatively movable supports for the golfer's feet. The back-foot support has a half-shoe for locating the instep of the back-foot and which can rotate about a vertical axis while simultaneously allowing the golfer to raise his heel. Stops prevent the golfer from moving his feet further than permitted by the aid, during the execution of the stroke. A horizontal pivotal axis on the back-foot support permits the half-shoe to tilt when the golfer's heel is raised.

Abstract: A process is provided for the electrochemical generation of N.sub.2 O.sub.5 in HNO.sub.3, whereby a solution of N.sub.2 O.sub.4 in HNO.sub.3 is electrolyzed. An electrolytic cell for the electrolysis is also provided, having substantially parallel electrodes in electrode compartments separated by a cell membrane. The anode is of Pt, Nb, Nb/Ta 40:60 alloy with a Pt coating. The cathode is Pt, stainless steel, Nb, Nb/Ta 40:60 alloy. The cell membrane is preferably a perfluorinated cationic exchange membrane. In use N.sub.2 O.sub.5 forms in the anolyte and N.sub.2 O.sub.4 increases in the catholyte. A suitable design of cell and its use in a single- or multi-stage electrolysis process is also described.