No abstract

Traces of various gases have been added to a stream of purified nitrogen gas prior to entering either a microwave or a condensed electrode discharge, and the effect of the presence of these gases on the steady flow rate of nitrogen atoms obtained from the discharge has been measured. Suggestions for the effect of the impurity gases on the possible reactions occurring in the discharge have been put forward. It seems probable that an important feature of the presence of the impurities may be their effect on the electron temperature in the discharge.

No abstract

The electrochemical intercalation of oxygen into La 2 CuO 4 has been carried out for the ®rst time in anhydrous organic±inorganic media such as dimethyl sulfoxide (DMSO)/0.1 M NaClO 4 or nBu 4 NBF 4 . The electrochemical reaction needs the presence of an oxygen source (KO 2 ) even with potential oxidising supporting electrolytes (NaClO 4 ). The anodic polarisation is performed at room temperature, with the aim of replacing the usual ef®cient but sometimes aggressive alkaline media. This so-called chimie douce reaction gave rise to noteworthy materials having compositions up to La 2 CuO 4.08 for which superconducting behaviour was observed below 42 K. The physical characteristics of the material (XRD, chemical composition, electronic properties) before and after controlled anodic polarisation are reported. The processes are time dependent and the oxygen stoichiometry could be controlled through reaction times.