A Miniature, Low Energy Spark Discharge System for Emission Spectrochemical Analysis of Solutions

A miniature spark discharge system is described for solution analysis by emission spectroscopy. Samples are introduced as dry particles formed by nebulization into a heated desolvation chamber. The spark is formed by the discharge of a coaxial capacitor through a stream of argon which transports the desolvated aerosol. A photoelectric, time-resolved detection system for mechanistic studies and analytical applications is described. The detection system consists of a synchronous integrator controlled by a digital timing and sequencing system. The time-resolved spectral characteristics of the source are discussed, and time resolution is shown to provide enhanced sensitivity. Analytical results are reported for a variety of elements.

The Dwarf Nova EX Hydrae

The object EX Hya is a dwarf nova with a binary period of 98.3 min (Mumford 1964, 1967). Warner (1972, 1973a) has observed two complete cycles of this star with a photoelectric time resolution of 5 sec. These observations suggested that EX Hya can be understood in terms of the model proposed by Warner and Nather (1971) in their discussion of U Gem. In this model, a white dwarf primary of a semi-detached binary system is surrounded by a disk of gas formed from matter transfered from the secondary, which is a cool dwarf star filling its Roche lobe.