A Fluorescence Technique to Measure Concentration Gradients near an Interface
A new fluorescence technique which measures the concentration profile in a mass transfer boundary layer is described. It uses a tracer whose fluorescent intensity is inversely proportional...
Regional Estimates of Gas Transfer Using an Airborne System
The aircraft-based eddy correlation technique was recently used to obtain regional observations of transfer processes of sensible and latent heat as well as carbon dioxide over wetlands...
Tracer Gas Transfer Technique for Shallow Bays
Developmental field tests using propane and Rhodamine WT tracers were conducted to adapt the tracer gas method for use in shallow bays. A special injection box was built to prevent mixing...
From Mean Fluxes to a Detailed Experimental Investigation of the Gas Transfer Process
Three new experimental techniques are discussed which allow a much more detailed investigation of the gas transfer process than any previous techniques. Using heat as a proxy tracer for...
Methane Tracer Technique for Gas Transfer at Hydraulic Structures
Using a simple headspace gas chromatographic technique, gas transfer at several hydraulic structures were investigated. Naturally occurring methane was used as a tracer gas to measure...
Measurement of Reaeration Coefficient with the Soluble Solids Probe
The results of analytical and experimental studies are presented, showing that the proposed method for indirect determination of gas transfer coefficients at gas-liquid interfaces, based...
A Gas Chromatographic Protocol for the Measurement of Krypton Gas in Water
This paper presents the results of a study to investigate the feasibility of using a gas chromatographic (GC) technique for the measurement of non-radioactive krypton gas concentrations...
Measurement of Stream Reaeration Rate Coefficients Using Propane Gas
Three determinations of the reaeration rate coefficient, K2, were made on a 1185-m reach of the upper Assabet River in Westborough and Northborough,...
Gas Transfer Measurements on an Ice-Covered River
Wasteload allocation for existing and proposed pulp mills in the Athabasca River Basin of northern Alberta, Canada, necessitated measurement of the atmospheric reaeration rate, K2,...
Carbon Dioxide Pressure in Surface Waters of Canadian Lakes
Direct measurements of the partial pressure (pCO2) of carbon dioxide were made in lakes of three study areas: ELA (the Experimental Lakes Area) and...
Oxygen Transfer at Spillways
A relationship for oxygen transfer efficiency, E, at spillways and gated spillways with a hydraulic jump or plunge pool, has been developed from conceptual considerations and fit to measurements...
Structure of the Drift Current Observed Below Capillary-Gravity Waves
Measurements by laser-Doppler velocimeter were performed in a wind-wave tank to investigate the structure of the water surface boundary layer under capillary-gravity wind waves in the...
Water Surface Flow and Exchange Induced by a Bubble Plume
Aeration is a common method to increase dissolved oxygen in the water of stratified (or non-stratified) lakes. In this method compressed air is injected at some depth, and gas is transferred...
Lysimeters for Evapotranspiration and Environmental Measurements
Lysimeters have been used extensively in the past to provide baseline information for development, calibration, and validation of evapotranspiration methods. This proceedings,
Instrumentation for SASW Testing
The Spectral-Analysis-of-Surface-Waves (SASW) method is presented. Various test setups and corresponding data reduction procedures are discussed. Several instrumentation systems have been...
In-Situ Calibration of USGS Piezometer Installations
Among the few potentially liquefiable sites around the world that have been permanently instrumented with pore-pressure transducers and accelerometers, only the Wildlife Site in the Imperial...
Use of Bender Elements in Soil Dynamics Experiments
Transducers employing piezoelectric bender elements have been found to be versatile sources and receivers of small-amplitude shear waves, with multiple potential applications. The constitutive...
Multi-Directional Wave Velocity by Piezoelectric Crystals
Piezoelectric ceramics are successfully used to measure velocities of waves propagating through a dry granular material assembly. Several directional shear and compression waves are measured...
Use of Piezoceramic Bender Elements in Soil Dynamics Testing
The use of piezoceramic bender elements is described to measure small strain, shear wave velocity distributions in soil models used in centrifuge and shake table testing. Experimental...
Infrared Detector Developments
Modern road transport systems rely on information from sensors to operate safely and efficiently. The sensors are typically used to provide vehicle counting, occupancy, speed measurement...
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