Automation of a Truck-Mounted Drill Rig
Truck-mounted drill rigs used for soils properties investigation, foundation evaluation, ore exploration, and producing monitor and water wells typically require, because of their weight,...
The Changing Face of Construction Management?Staffing up for a Major Program
The East Bay Municipal Utility District's (District) Wastewater Department annual construction program grew from $2.4 million in 1986 to $60 million in 1991. The District...
Environmental Engineering
This proceedings,
The Debate Over Large Dams
Dam megaprojects across the globe are under increasing scrutiny. Critics say large dams have clearly lost their luster. While the outcry over huge public subsidies and high ecological...
Water, Water, Where?
Water�who gets it, where it comes from, who pays for it�has always been a central issue in California. Rapidly increasing demand, fierce environmental opposition to new sources and a drought...
Burying By the Bale
The Gallatin National Landfill, now under construction in central Illinois, incorporates multiple safeguards to isolate refuse from surrounding water and soil with an inward gradient design....
Nutrified Sludge
A new biological treatment process, Nutrification, enables a wastewater treatment plant to remove phosphorus from influent water at an operating and maintenance cost 35% less than that...
Landfill Park: From Eyesore to Asset
By reclaiming a 50 acre landfill as a recreational area, Cambridge, Mass. increased its open space by 20%. The park includes three softball and three soccer fields, one multisport field,...
Effect of Gas Flow on Physical Absorption
Air blowing over a liquid surface can greatly increase the rate of physical absorption of a gaseous component. This increase is associated with the initiation of waves and a change in...
Air-Water Transfer: The Role of Partitioning
A review is presented of the role of air-water equilibrium in determining the direction and rate of transfer of chemicals between water bodies and the atmosphere. Because this diffusive...
Formation of Droplets from Bursting Bubbles at an Air-Water Interface
The breakup of an air bubble at a still water surface leads to the formation of two distinct droplet families known respectively as film drops and jet drops. The former are the tiny fragments...
The Effect of Surface Films on Concentration Fluctuations Close to a Gas/Liquid Interface
Modeling of gas/liquid mass transport requires knowledge concerning the behavior of near-surface concentration fluctuations at clean and film-covered gas/liquid interfaces. Previous measurements...
Properties of Small-Scale Waves in Sheared Gas-Liquid Flows
Small wind-generated waves are examined theoretically and experimentally in a small laboratory flow system, at conditions close to neutral stability in an attempt to better characterize...
Surface Renewal Due to Large Flow Structures in Open Channel Flow
It is shown that under certain flow conditions, surface renewal cannot be understood as an exclusive result of the bursting occurring near the wall, as proposed by several authors. Flow...
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...
Airborne Remote Sensing of Breaking Waves with Implications for Gas Exchange
It is shown that airborne remote sensing can potentially relate gas mixing effects within a temporally evolving breaking wave to relectivity changes, and can identify the intensity of...
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...
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