Annealing by flame

When an annealing oven is not available, even quite large pieces of equipment can be annealed by flame. Apparatus assembled on the bench can often only be annealed by a flame. As a general principle each joint should be annealed as it is completed, unless a further join is to be made, or another operation is to be performed immediately in the same region or so near to it that the whole of the first joint can be kept hot—then the whole is annealed together. 

With tubing up to about 30 mm in diameter the whole bend can be annealed by flame at the finish, but above this diameter it is advisable to anneal each portion for a few minutes after it is bent and shaped, and before one moves on to the next portion. With extra large tubing it is better to have two workers, one on either side of the tube, each with a hand torch. 

The polypeptide polyalanine was synthesized1 and characterized by Matrix Assisted Laser Desorption Ionization (MALDI) and amino acid hydrolyses. Monolayers of either l- or D-polyalanine polypeptides, in the form of an a-helix, were prepared by self-assembly on a borosilicate slide that was coated with a 200-300 nm thick gold film (Metallhandel Schroer Gmbh). Prior to the adsorption, the gold slides were annealed by flame and only then inserted into a 1 mM peptide solution of... 

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