104 JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY MARCH 1991 VOL. 6 Future Issues will Include- Optimization of Cold Vapour Atomic Ab- sorption Spectrometric Determination of Mercury With and Without Almagama- tion by Subsequent Use of Complete and Fractional Factorial Designs With Uni- variate and Modified Simplex Methods- George A. Zachariadis and John A. St rat is High-performance Liquid Chromato- graphy-Atomic Absorption Spectro- metry Interface for the Determination of Selenoniocholine and Trimethylselononi- um Cations Application to Human Urine-Jean-Simon Blais A. Hu- yghues-Despointes Georges Marie Momplaisir and William D. Marshall Optimization of Mass Scanning Rate for the Determination of Lead Isotope Ratios by an Inductively Coupled Plasma Mass Spectrometer-Naoki Furuta Flow Injection Flame Atomic Spectro- metric Determination of Aluminium Iron Calcium Magnesium Sodium and Potassium in Ceramic Materials by On- line Dilution in a Stirred Chamber-V.Carbonell A. Sanz A. Salvador and M. de la Guardia Direct Solid Sampling in Capacitively Coupled Microwave Plasma Atomic Emission Spectrometry-J. D. Wine- fordner Abdalla H. Ali and Kin C. Ng Evaluation of a 13.56 MHz Capacitively Coupled Plasma as a Detector for Gas Chromatographic Determination of Or- ganotin Compounds-Degui Huang and Michael W. Blades Application of a High Resolution Induc- tively Coupled Plasma Mass Spectrome- ter to the Measurement of Long-lived Radionuclides-Chang-Kyu Kim Riki Seki Shigemitsu Morita Yuichi Takaku Yasuhito Igarashi and Ma- sayoshi Yamamoto Atomic Spectrometry Update The Update in the April issue is- Clinical Materials Foods and Beverag- es-David J. Halls Helen M. Crews Andrew Taylor and Simon Branch