Abstract: At least one of selectivity and reaction rate of photosensitized vapor phase dimerizations, including dehydrodimerizations, hydrodimerizations and cross-dimerizations of saturated and unsaturated organic compounds is improved by conducting the dimerization in the presence of hydrogen or nitrous oxide.

Abstract: A stringed musical pick or plectrum dispenser for receiving, retaining, and dispensing a pick, the dispenser being mounted in fixed relation to an instrument sound board adjacent the instrument strings. Each pick is wafer thin and generally triangular in shape. The dispenser may be mounted on a pick guard which has a first edge alignable with the instrument string that is last plucked to guard against, and prevent, continued downward travel of the pick thus protecting the finish on the instrument sound board. A dispenser housing has a perimetral wall with upper and lower edges. The housing defines in cross-section the general configuration of a pick. A bottom side is affixed to the lower wall edge and a top side is affixed to the upper wall edge. A pick receiving and dispensative opening is formed in the top side. The opening receives a pick and provides an inner surface for engaging and retaining the pick in the dispenser while exposing a pick surface through the opening.