CONTENTS Volume 25, Number 1 Light scattering for particle characterization A. R. Jones Sewage sludge combustion J. Werther and T. Ogada Volume 25, Number 2 Modelling ash deposition in pulverized coal-fired applications F. C. C. Lee and F. C. Lockwood Eulerian and Lagrangian approaches for predicting the behaviour of discrete particles in turbulent flows G. Gouesbet and A. Berlemont Review of the application of Newton’s third law in physics Patrick Cornille Gliding arc gas discharge A. Fridman, S. Nester, L. A. Kennedy, A. Saveliev and O. Mutaf-Yardimci Volume 25, Number 3 Quantitative measurements of absolute concentrations of intermediate species in flames S. Cheskis Combustion-chamber crevices: the major source of engine-out hydrocarbon emissions under fully warmed conditions A. C. Alkidas Research on combustion of black-liquor drops A. Macek ill Design of scrubbers for condensing boilers F. Haase and H. Koehne Volume 25, Number 4 Guest Editorial The effect of coal quality on meeting the 1995 ozone season NO, cap at New York State Electric & Gas J. G. De Angelo and C. E. Sjoberg Modeling of lean premixed combustion in stationary gas turbines B. Scott Brewster, S. M. Cannon, J. R. Farmer and F. Meng Components, formulations, solutions, evaluation, and application of comprehensive combustion models A. M. Eaton, L. D. Smoot, S. C. Hill and C. N. Eatough Volume 25, Number 5 Automotive spark-ignited direct-injection gasoline engines F. Zhao, M.-C. Lai, D.L. Harrington Volume 25, Number 6 Cold-start hydrocarbon emissions in port-injected gasoline engines N. A. Henein and M. K. Tagomori Conditional moment closure for turbulent combustion A. Y. Klimenko and R. W. Bilger Erratum: Research on combustion of black-liquor drops [Progress in Energy and Combustion Science 1999; 25: 275-304] A. Macek