作者：
OSTENDORF, DWMOYER, EEXIE, YFRAJAN, RVDavid W. Ostendorf (Civil Engineering Department
University of Massachusetts Amherst MA 01003) is an associate professor in the Environmental Engineering Program of the Civil Engineering Department of the University of Massachusetts at Amherst. His research interests include unconfined aquifer contamination hazardous waste site remediation and analytical modeling of problems in environmental fluid mechanics. Ostendorf is a Registered Professional Engineer in Massachusetts and a member of the American Geophysical Union American Society of Civil Engineers Soil Science Society of America Water Pollution Control Federation and Association of Environmental Engineering Professors as well as the National Ground Water Association. Ellen E. Moyer (Civil Engineering Department
University of Massachusetts Amherst MA 01003) is a doctoral candidate in the Environmental Engineering Program of the Civil Engineering Department of the University of Massachusetts at Amherst with an M.S. degree in environmental engineering from that institution. Her research interests include subsurface investigation soil venting bioremediation and analytical modeling of subsurface contamination. She has six years of professional experience managing hazardous waste site investigation and cleanup projects and is a member of the National Ground Water Association and the American Society of Civil Engineers. Yuefeng Xie (Civil Engineering Department
University of Massachusetts Amherst MA 01003) is a postdoctoral research associate in the Environmental Engineering Program of the Civil Engineering Department of the University of Massachusetts at Amherst. His research interests include environmental analyses drinking water treatment and the chemical characterization and removal of disinfection by-products. A graduate with a Ph.D. and an M.S. in environmental engineering and a B.S. in chemistry and chemical engineeering from Tsinghua University Beijing China Xie is a member of the American Water Works Association and the Water Poll
The diffusion of 2,2,4-trimethylpentane (TMP) and 2,2,5-trimethylhexane (TMH) vapors out of residually contaminated sandy soil from the U.S. environmental Protection Agency (EPA) field research site at Traverse City, ...
The diffusion of 2,2,4-trimethylpentane (TMP) and 2,2,5-trimethylhexane (TMH) vapors out of residually contaminated sandy soil from the U.S. environmental Protection Agency (EPA) field research site at Traverse City, Michigan, was measured and modeled. The headspace of an intact core sleeve sample was swept with nitrogen gas to simulate the diffusive release of hydrocarbon vapors from residual aviation gasoline in and immediately above the capillary fringe to a soil-venting air flow in the unsaturated zone. The resulting steady-state profile was modeled using existing diffusivity and air porosity estimates in a balance of diffusive flux and a first order source term. The source strength, which was calibrated with the observed flux of 2,2,4-TMP leaving the sleeve, varied with the residual gasoline remaining in the core, but was independent of the headspace sweep flow rate. This finding suggested that lower soil-venting air flow rates were in principle as effective as higher air flow rates in venting LNAPL vapors from contaminated soils. The saturated vapor concentration ratio of 2,2,4-TMP to 2,2,5-TMH decreased from 6.6 to 3.5 over the duration of the experiments in an expression of distillation effects. The vertical profile model was tested against sample port data in four separate experiments for both species, yielding mean errors ranging from 0 to -24 percent in magnitude.
作者：
OSTENDORF, DWLEACH, LEHINLEIN, ESXIE, YF1 David W. Ostendorf is an associate professor in the Environmental Engineering Program of the Civil Engineering Department at the University of Massachusetts (Civil Engineering Department
University of Massachusetts Amherst MA 01003). His research interests include unconfined aquifer contamination hazardous waste site remediation and analytical modeling of problems in environmental fluid mechanics. Dr. Ostendorf is a registered professional engineer in Massachusetts and a member of the American Geophysical Union American Society of Civil Engineers Soil Science Society of America Water Pollution Control Federation and Association of Environmental Engineering Professors as well as the National Water Well Association.2 Lowell E. Leach is an environmental engineer with the Robert S. Kerr Environmental Research Laboratory of the U.S. Environmental Protection Agency (RS Kerr Environmental Research Laboratory U.S. EPA P.O. Box 1198 Ada OK74820). Leach received his B.S. ingeological engineering at the University of Oklahoma in 1959 and has been a registered professional engineer in Oklahoma since 1966. With 29 years of experience in field applications of geological engineering he is responsible for developing methodology for sampling ground water and subsurface materials for the Robert S. Kerr Environmental Research Laboratory.3 Erich S. Hinlein is a research assistant in the Environmental Engineering Program of the Civil Engineering Department at the University of Massachusetts (Civil Engineering Department University of Massachusetts Amherst MA 01003). His research interests include ground water pollution hazardous waste site investigation and transport processes in unconfined aquifers. Hinlein graduated with a B.S. in electrical and computer engineering from the University of Massachusetts at Amherst in May 1985 and entered the Environmental Engineering Master's Degree Program in January 1989.4 Yuefeng Xie is a postdoctoral research associate in the Environmental Engineering Program of the Civil E
Two complementary field sampling methods for the determination of residual aviation gasoline content in the contaminated capillary fringe of a fine, uniform, sandy soil were investigated. The first method featured fie...
Two complementary field sampling methods for the determination of residual aviation gasoline content in the contaminated capillary fringe of a fine, uniform, sandy soil were investigated. The first method featured field extrusion of core barrels into pint-size Mason jars, while the second consisted of laboratory partitioning of intact stainless steel core sleeves. The barrel extrusion procedure involved jar headspace sampling in a nitrogen-filled glove box, which delineated the 0.7m thick residually contaminated interval for subsequent core sleeve withdrawal from adjacent boreholes. Soil samples removed from the Mason jars (in the field) and sleeve segments (in the laboratory) were subjected to methylene chloride extraction and gas chromatographic analysis to compare their aviation gasoline content. The barrel extrusion sampling method yielded a vertical profile with 0.10m resolution over an essentially continuous 5.0m interval from the ground surface to the water table. The sleeve segment alternative yielded a more resolved 0.03m vertical profile over a shorter 0.8m interval through the capillary fringe. The two methods delivered precise estimates of the vertically integrated mass of aviation gasoline at a given horizontal location, and a consistent view of the vertical profile as well. In the latter regard, a 0.2m thick lens of maximum contamination was found in the center of the capillary fringe, where moisture filled all voids smaller than the mean pore size. The maximum peak was resolved by the core sleeve data, but was partially obscured by the barrel extrusion observations, so that replicate barrels or a half-pint Mason jar size should be considered for data supporting vertical transport analyses in the absence of sleeve partitions.
The frequency-time finite element model TEA-NL is used to investigate tidal propagation and circulation in the English Channel and the southern North Sea, in the context of the Tidal Flow Forum benchmark. Quality of T...
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The frequency-time finite element model TEA-NL is used to investigate tidal propagation and circulation in the English Channel and the southern North Sea, in the context of the Tidal Flow Forum benchmark. Quality of TEA-NL simulations, relative to both field data and simulations by other numerical models is discussed. Sensitivity analyses are performed with regard to the effect on accuracy of bottom friction, and the effect on computational cost of the strategy used to harmonically decompose and iterate non-linear loading terms in the shallow water equations.
作者：
KINNEY, ETCONSTANT, AEEdward T. Kinney:is presently director of the Machinery Group
Naval Sea Systems Command (NavSea). He graduated from Michigan State University in 1952 and joined the Bureau of Ships Engineer-In-Training Program. Mr. Kinney has held a variety of technical and senior management positions in NavSea and the Naval Material Command. He has authored a number of technical articles and papers and has been a contributing author to the Naval Engineers Journal. He is a past president of the Association of Scientists and Engineers and holds membership in ASNE SNAME Federal Conference of Environmental Engineers and ASME and is chairman of the ASME Shipbuilding Standards Machinery Committee. Alexander E. Constant:is a native of Newport
Rhode Island and a graduate of Pennsylvania Military College from which he received his BS degree in civil engineering in 1960. After two years with the U.S. Forest Service working in civil sanitary engineering designing recreational facilities he joined the Vermont Water Resources Department as a project engineer. He was recruited by the Navy in 1966 and he accepted a position in the Piping Systems Branch where he attained the position of director. At present he is head of the Auxiliary Equipment Division Naval Sea Systems Command where for the past six years he has been responsible for the design operation maintenance and life cycle support for the majority of the U.S. Navy's shipboard auxiliary equipment. He has been a member of U.S. and international committees on standardization and has been a delegate representing the U.S. at several meetings throughout the world.
This paper presents improvements in logistics support of hull, mechanical, and electrical (HM&E) components through standardization to the piece part level. The process of component standardization is outlined and...
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This paper presents improvements in logistics support of hull, mechanical, and electrical (HM&E) components through standardization to the piece part level. The process of component standardization is outlined and compared with traditional HM&E acquisition approaches. The impact of standardization on logistics support is presented with case examples cited to graphically demonstrate how logistics improvements are derived. The paper also presents standardization costs and benefit analyses. A compelling case for increased HM&E standardization efforts is made from a logistics improvement perspective.
作者：
Brezonik, Patrick L.Kratzer, Charles R.Respectively
professor of Environmental Engineering Department of Civil and Mineral Engineering University of Minnesota Minneapolis Minnesota 55455 and Graduate Student
Department of Environmental Science and Engineering Program UCLA Los Angeles California 90024.
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