Gas Transfer at Water Surfaces

The transfer across the surface of environmental waters is of interest as an important phase in the geophysical and natural biochemical cycles of numer­ ous substances;

1. Physico-Chemical Fundamentals.- Physical-chemical phenomena and molecular properties.- The determination of Henry’s Constant for volatile organics by equilibrium partitioning in closed systems.- Volatilization of chlorinated hydrocarbons from water.- The ratio of gas-phase to liquid-phase mass transfer coefficients in gas-liquid contacting processes.- Absorption of gases at condensing and evaporating water surfaces.- The effects of evaporation and condensation on an absorption process.- 2. Turbulence near Gas-Liquid Interfaces.- Turbulence structure and turbulent diffusion near gas-liquid interfaces.- Turbulence measurements near the free surface in stirred grid experiments.- A laboratory technique for investigating the relationship between gas transfer and fluid turbulence.- Carbon dioxide transfer at the gas/water interface as a function of system turbulence.- Turbulence structure of wavy stratified air-water flow.- Current fluctuations in the surface waters of small lakes.- Moisture and heat transport in a stably stratified boundary layer over a water surface.- 3. Interfacial Motions and Instabilities.- Wind-wave effects on gas transfer.- Interfacial motion observed during experiments on air-water gas transfer.- A laboratory study of the velocity field below surface gravity waves.- The roles of Langmuir circulations in gas transfer across natural water surfaces.- Measurements of the fluctuating pressure in the turbulent boundary layer over progressive, mechanically generated water waves.- Experimental studies of surface wave breaking and air entrainment.- Bubbles produced by breaking wind waves.- The role of bubbles for gas transfer from water to air at higher windspeeds. Experiments in the wind-wave facility in Hamburg.- A new optical bubble measuring device; A simple model for bubble contribution to gas exchange.- Contribution of bubbles to gas transfer across an air-water interface.- Entrapment and transport of bubbles by plunging water.- 4. Conceptual Models and Parameterizations of Gas Transfer.- Conceptual models of gas exchange.- A comparison of turbulent mass transfer at gas-liquid and solid-liquid interfaces.- The variation of the gas transfer coefficient with molecular diffusity.- Wind/wave-tunnel experiment on the Schmidt number — and wave field dependence of air/water exchange.- A model of interfacial gas transfer for a well-roughened sea.- Turbulent transfer across smooth and rough surfaces.- Reaeration of open channel flow.- Dependence of oxygen transfer rate on energy dissipation during surface aeration and in stream flow.- Wind effects on air-water oxygen transfer in a lake.- Reaeration and wind induced turbulence shear in a contained water body.- 5. Field and Laboratory Experimental Techniques.- Field techniques for reaeration measurements in rivers.- Gas transfer rate coefficient measurement of wastewater aeration equipment by a stable isotope krypton/lithium technique.- Reaeration studies on some New Zealand rivers using methyl chloride as a gas tracer.- Dichlorodifluoromethane (Freon-12) as a tracer for nitrous oxide release from a nitrogen-enriched river.- An assessment of the radiotracer technique for measuring reaeration rates in large river systems.- Measurements of wind effects on water-side controlled gas exchange in riverine systems.- Optimum application of the radon deficit method to obtain air-sea gas exchange rates.- Parametrization of air/lake gas exchange.- Simultaneous in situ determination of dissolved gases by gas chromatography.- 6. Climate and Oceanographic Applications.- Gas exchange measurements in natural systems.- The role of oceanic whitecaps in air-sea gas exchange.- On the exchange of oxygen and carbon dioxide between ocean and atmosphere in an eastern boundary current.- Invasion of fossil fuel CO2 into the ocean.- In situ pH measurements as an indicator of CO2 gas transfer in glacial meltwaters.- The transfer of mercury at the air/water interface.- Exchange rates of dimethyl sulfide between ocean and atmosphere.- Laboratory observations on transfer of atmospheric oxygen into stratified seawater.- 7. Water Quality and Engineering Applications.- The significance of gas exchange in water quality assessment and planning.- The sensitivity of the dissolved oxygen balance to predictive reaeration equations.- Estimation of volatilization of toxics for multimedia modeling.- Reaeration measurement in swamp streams: Radiotracer case studies.- Prediction of dissolved gas transfer in spillway and outlet works stilling basin flows.- Carbon dioxide desorption from the activated sludge at the waste water treatment plants.- Volatilization of fission products in nuclear reactor buildings.- Self-propelled weir aerators.