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EPAS APPROACH TO VADOSE ZONE MONITORING AT RCRA FACILITIES

GROUND WATER MONITORING AND REMEDIATION 1993年第1期13卷 151-158页

作者： DURANT, ND MYERS, VB ECCLES, LA Washington D.C. 20460) has worked as an environmental scientist in the RCRA corrective action program at EPA since 1989. After graduating from Colgate University in 1987 Durant worked for GeoTrans Inc. conducting hydrogeologic investigations at numerous waste disposal sites throughout the northeastern United States. At present Durant is pursuing an M.S. degree in environmental science from The Johns Hopkins University. His research is focused on enhancing in situ biodegradation of aromatic organic compounds in the subsurface. Washington D. C. 20460) graduated from The Johns Hopkins University in 1972 with a B.A. degree in natural sciences. Myers received a Ph.D. in oceanography from Florida State University in 1977. During 1978 he held a post doctoral fellowship at University of Florida in the Department of Environmental Engineering and Science. From 1979 to 1983 Myers was employed by the Florida Department of Environmental Regulation where he worked on environmental restoration projects. Since 1984 Myers has worked at EPA managing RCRA ground water monitoring and corrective action programs. Lawrence A. Eccles (U.S. Environmental Protection Agency Environmental Monitoring Systems Laboratory P.O. Box 93478 Las Vegas NV 89193–3478) is a hydrologist with the EPA Environmental Monitoring Systems Research Laboratory in Las Vegas Nevada. Eccles is responsible for the development of vadose zone and in situ monitoring techniques and guidelines. After graduating from Monmouth College with a B.S. degree in chemistry Eccles performed graduate work in chemical engineering at New Mexico State University. He received formal training in hydrology in 1969 from the U.S. Geological Survey in Denver and worked with that agency before joining EPA at Las Vegas in 1984. One of his co-authored articles was chosen for the Best Paper Award by the journal Ground Water in 1975 and another was the subject of a cover story for Water Well Journal in 1977.

The U.S. Environmental Protection Agency (EPA) recently proposed to amend federal regulations to require vadose zone monitoring at certain hazardous waste facilities. To support this proposal, EPA evaluated previous policy on vadose zone monitoring and examined advances in vadose zone monitoring technology. Changes in EPA vadose zone monitoring policy were driven by demonstrated advances in the available monitoring technology and improvements in understanding of vadose zone processes. When used under the appropriate conditions, currently available direct and indirect monitoring methods can effectively detect contamination that may leak from hazardous waste facilities into the vadose zone. Direct techniques examined include soil-core monitoring and soil-pore liquid monitoring. Indirect techniques examined include soil-gas monitoring, neutron moderation, complex resistivity, ground-penetrating radar, and electrical resistivity. Properly designed vadose zone monitoring networks can act as a complement to saturated zone monitoring networks at numerous hazardous waste facilities. At certain facilities, particularly those in arid climates where the saturated zone is relatively deep, effective vadose zone monitoring may allow a reduction in the scope of saturated zone monitoring programs.

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UNDERWATER INSPECTION FOR WELDING AND OVERHAUL

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NAVAL ENGINEERS JOURNAL 1993年第5期105卷 37-42页

作者： MITTLEMAN, J SWAN, L John Mittleman:is a mechanical engineer at the Naval Surface Warfare Center Dahlgren Division Coastal Systems Station in Panama City Florida. His Primary Responsibilities are in the development of underwater nondestructive testing equipment for use by fleet divers and inspectors. He also performs research in the characterization of metal microstructure through ultrasonic scattering measurements. Mr. Mittleman received his BS from Cornell University in 1969 and science master's in ocean engineering from the Massachusetts Institute of Technology in 1970. His research currently supports doctoral studies with Iowa State University. Mr. Mittleman received the American Society of Naval Engineer's Solberg Award in 1981 for his contributions to underwater ship hull inspection. Mr. Mittleman is a member of ASNE ASNT ASTM IoD Sigma Xi Tau Beta Pi and Phi Kappa Phi. Lisa Swan:is a mechanical engineer at the Naval Surface Warfare Center in Panama City Florida. She is involved in nondestructive testing engineering primarily in the underwater arena. Ms. Swan holds a bachelor of science in materials engineering from North Carolina State University. She is a graduate of the Federal Women's Executive Leadership Program. Ms. Swan is a member of ASNT.

Significant progress has been made in making underwater ultrasonic thickness gauging and magnetic particle inspections available to the fleet. Under sponsorship from the Naval Sea Systems Command, Director of Ocean engineering, Underwater Ship Husbandry Division (NavSea 00C5), the Coastal Systems Station has developed complete hardware packages supporting these two nondestructive test methods, and has introduced them to military inspectors at a shore intermediate maintenance activity, a destroyer tender, and a naval shipyard. Performance trials conducted prior to taking the systems to the field have been accepted by NavSea, Ships' Concepts Group, materials Subgroup, Metals Division (NavSea 5142) as evidence that these inspections can reliably be performed underwater. Avenues for certifying specially trained divers and inspectors are being developed;for the first time the Navy will have all of the elements in place for underwater inspections satisfying the requirements of Mil-Std-271 (Requirements for Nondestructive Testing Methods) and the Naval Ships' Technical Manual Chapter 074. Underwater ultrasonic thickness gauging has also been slated for use in the fleet, as data from laboratory and field trials have consistently shown that reliable results can be obtained by a team comprising a certified topside inspector and a diver. In tests performed at the Ship Repair Facility (SRF), Yokosuka, underwater readings were compared to those taken in dry dock by SRF inspectors, and independently by contract inspectors. On the basis of approximately 800 locations, differences between the data sets were found to be randomly distributed, with a standard deviation on the order of 0.02''. This level of accuracy is largely sufficient to distinguish plate which will need replacement during overhaul, or plate which is thick enough to weld on.

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FIELD SAMPLING OF RESIDUAL AVIATION GASOLINE IN SANDY SOIL

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GROUND WATER MONITORING AND REMEDIATION 1991年第2期11卷 107-120页

作者： OSTENDORF, DW LEACH, LE HINLEIN, ES XIE, YF 1 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 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.

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Detailed assessment of partial thermodynamic quantities of tin in molten Bi-Sn alloys from electromotive force measurements

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Metallurgical Transactions B 1990年第1期21卷 87-96页

作者： Cho, Seung-Am Camisotti, Roberto Vélez, Mariano H. Graduate Program of Metallurgy and Materials Science Venezuelan Institute of Scientific Research (IVIC) Caracas 1020A Apartado 21827 Venezuela School of Metallurgical Engineering and Materials Science Central University of Venezuela Caracas 1050A Apartado 50361 Venezuela Conduven Company Caracas Venezuela Department of Materials Science and Engineering Massachusetts Institute of Technology Cambridge 02139 MA United States

All the partial thermodynamic quantities, including the activity and activity coefficient of tin, a Sn and γSn, in the liquid Bi-Sn alloys between 300 °C and 500 °C are assessed in detail from electromotive...

All the partial thermodynamic quantities, including the activity and activity coefficient of tin, a_Sn and γ_Sn, in the liquid Bi-Sn alloys between 300 °C and 500 °C are assessed in detail from electromotive force (emf) data. The emf values were obtained from a modified molten salt electrolyte concentration cell that had extraordinary stability within +0.005 mV. The composition dependence of γ_Sn did not follow Darken's quadratic formalism, nor did the alloy behave as a regular solution. The excess partial quantities, Δ-H_Sn, Δ-S_Sn^xs, and Δ-G_Sn^xs, are oscillating across the composition, and the activity curve exhibits double, positive and negative, deviations from Raoult's law. The a_Sn, γ_Sn, and Δ-G_Sn^xs change from positive to negative departure from ideality in the tin-rich region beyond about x_Sn = 0.82. All those partial quantities and γ_Sn^o, including the β° (the α function of tin) at infinite dilution, are determined accurately by means of Chiotti's method. © 1990 The Minerals, Metals & Material Society.

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AN APPLICATION OF TOTAL QUALITY MANAGEMENT AT AN INTERMEDIATE MAINTENANCE ACTIVITY

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NAVAL ENGINEERS JOURNAL 1990年第6期102卷 35-43页

作者： NEEDHAM, WD USN is currently assigned as the Pacific Submarine Force maintenance officer in Pearl Harbor Hawaii. He is a 1972 Magna Cum Laude graduate of Duke University with a BS in mechanical engineering a 1983 graduate of Central Michigan University with an MA in business management and a 1986 graduate of MIT with an MS in materials science and an OE in ocean engineering. Cdr. Needham was selected for the Nuclear Power Program and following initial qualification on the USSGrayling (SSN-646) served as production training assistant officer at S7G Prototype and as engineer officer of USSNathan Hale (SSBN-623). He transferred to the EDO community in 1981 and has served as nuclear repair officer at Norfolk Naval Shipyard and as repair officer of USSHunley (AS-31). His awards include the Meritorius Service Medal with gold star the Navy Commendation Medal the Navy Achievement Medal the Spear Foundation Award the Vice Admiral C. R. Bryan Award and the Award for Excellence in Corrosion Engineering of the Chemical Process Industries. He is a registered professional engineer in the state of Virginia.

The current budget and resource constrained fiscal environment mandates positive measures to improve productivity. The management practices of the last four decades are no longer valid. The Department of Defense (DoD) has issued broad guidelines for a restructuring of all subordinate commands and agencies called total quality management (TQM). The precepts of TQM are not new. They are the very same precepts prescribed by numerous management and quality control experts for the past decade to reverse the downward trends in the productivity of American industry. The program elements of TQM are broad in scope, as they must be for an organization as large and diverse as DoD. The implementation of TQM at the local command level is left to the local commander. This is no mean task, as TQM is a radical departure from traditional management practice in every aspect of an organization. This article reports on the implementation of TQM at a local command, the USS Hunley , a naval auxiliary support ship whose primary mission is the repair and maintenance of a squadron of nuclear-powered submarines in Norfolk, Virginia.

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FLAMMABILITY AND TOXICITY OF COMPOSITE-materials FOR MARINE VEHICLES

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NAVAL ENGINEERS JOURNAL 1990年第5期102卷 45-54页

作者： SEVART, JL GRIFFIN, OH GURDAL, Z WARNER, GA Jeffrey L. Sevart:is a native of Kansas and a 1985 graduate of Kansas State University with a B.S. in mechanical engineering (magna cum laude). After working as a stress analysis engineer at Boeing Military Airplane Company in Wichita Kans. he attended Virginia Polytechnic Institute and State University and received an M.S. in engineering mechanics in February 1988. He currently resides in Akron Ohio working as a research engineer in tire composites research at The Goodyear Tire and Rubber Company. O. Hayden Griffin Jr.:received his B.S. and M.S. in mechanical engineering from Texas Tech University in 1970 and 1971 respectively. He received his Ph.D. in engineering mechanics from Virginia Polytechnic Institute and State University in 1980. Prior to joining the faculty of Virginia Polytechnic Institute and State University as associate professor of engineering science and mechanics in September 1985 he was employed at the U.S. Naval Surface Warfare Center (Dahlgren Virginia) BF Goodrich Tire Group (Akron Ohio) the Bendix Advanced Technology Center (Columbia Maryland) and the Johns Hopkins University Applied Physics Laboratory (Laurel Maryland). He is currently an associate director of the Virginia Institute for Material Systems. He is a registered professional engineer in Virginia and is a member of the American Society of Mechanical Engineers and the American Society for Composites. Zafer Gürdal:received his M.S. in mechanical and aerospace engineering from Illinois Institute of Technology in 1981 and his Ph.D. in aerospace engineering from Virginia Polytechnic Institute and State University in 1985. He worked as a research associate in the Aerospace and Ocean Engineering Department at Virginia Tech before joining the Engineering Science and Mechanics Department as an assistant professor in September 1985. Professor Gürdal's research interests include: composite structures failure mechanics of composites structural optimization and damage tolerant design. He is a member of the American Institute

Characteristics of both thermoplastic and thermoset composite materials as they pertain to marine vehicle applications are discussed. Comparison of various material selection factors such as strength, damage and moisture resistance, and flammability and toxicity as well as cost and availability of thermoset and thermoplastic composite materials are presented. Methods for testing and reducing the flammability and toxicity are discussed. Many commercially available composite systems are reported to provide favorable characteristics for marine applications. Although there seems to be a need for improved production technology for thermoplastics, they present potential advantages in physical properties over thermoset composites.

关键词： Composite materials

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A NEW DYNAMIC CORROSION TEST FOR DENTAL materials

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DENTAL materials 1989年第6期5卷 411-414页

作者： MELETIS, EI GIBBS, CA LIAN, K Louisiana State University Materials Science Engineering Program Mechanical Engineering Department Baton Rouge LA 70803-6413 United States University of California Biomedical Engineering Graduate Group Davis CA 95616 United States

A new laboratory technique has been developed in an effort to simulate the deterioration processes occurring in dental amalgam restorations while they are exposed to attack by the oral environment and simultaneously subjected to biting forces during mastication. This combined mechanical wear and corrosion action may be one of the major contributors to the degradation of dental amalgam restorations. The technique provides the capability of varying and measuring electrochemical and mechanical parameters during a sliding-wear process in a corrosive environment. A high-copper dental amalgam was selected and tested to demonstrate the applicability of the method in evaluating and studying the effects of the combined action of wear and corrosion processes on dental materials. For the particular amalgam material tested in the present study, it was found that sliding-wear significantly lowered its corrosion potential and increased corrosion rates by at least one order of magnitude.

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BOTTOM BOUNCE ARRAY SONAR SUBMARINE (BBASS)

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NAVAL ENGINEERS JOURNAL 1989年第5期101卷 59-72页

作者： JACKSON, HA NEEDHAM, WD SIGMAN, DE USN (RET.) Capt. Harry A. Jackson USN (Ret.) is a graduate of the University of Michigan in naval architecture and marine engineering and completed the General Electric Company's 3-year advanced engineering course in nuclear engineering. He has been an independent consulting engineer and participated in projects involving deep submergence waste disposal water purification and submarine design both commercial and government. Cdr. William D. Needham USN is currently assigned as the repair officer of USS Hunley (AS-31) in Norfolk Virginia. He received a regular commission through NROTC at Duke University where he graduated magna cum laude in mechanical engineering. Selected for the Nuclear Power Program he served as a division officer on the USS Grayling (SSN-646) as the production training assistant at the MARE Prototype Reactor in New York and as blue crew engineer of the USS Nathan Hale (SSBN-623) where he completed the requirements to be designated qualified for command of submarines. Following line transfer to the EDO community in 1981 he completed a tour as nuclear repair officer (Code 310) at Norfolk Naval Shipyard and earned master of science in materials science and ocean engineer's degrees at MIT. His awards include the Meritorius Service Medal Navy Commendation Medal Navy Achievement Medal Spear Foundation Award and the Vice Admiral C.R. Bryan Award. Cdr. Needham also holds a master of arts degree in business management from Central Michigan University. Capt. Jackson was technical director of Scorpion Search Phase II. The on-site investigation included descending over 12 000 feet to the bottom of the ocean. He was also supervisor of one of the Navy's largest peacetime shipbuilding and repair programs. His responsibilities included supervision of design production and contract administration. Capt. Jackson was third from the top in managaement of a major shipyard and responsible for design material procurement work order and financial control of two major surface ship prototypes as well a

Anticipated technological advances in the quieting of potential adversary submarines mandate the use of increasingly effective detection systems for U.S. ASW forces. Based on the assumptions that sonar will continue to be the primary means of detection and that the effectiveness of each individual sonar element will not change markedly, one must increase the projected area of the sonar array to improve its capability. The primary SSN mission of anti-submarine warfare will hence require increasing the hull area devoted to the primary sonar detection system. A revolutionary hull form is proposed that maximizes the area available for this purpose. The advantages and disadvantages of this hull form are discussed and feasibility study level design parameters and arrangements presented.

关键词： Submarines

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ADVANCED-CYCLE GAS-TURBINES FOR NAVAL SHIP PROPULSION

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NAVAL ENGINEERS JOURNAL 1984年第3期96卷 262-271页

作者： BOWEN, TL GROGHAN, DA Thomas L. Bowen began his career at the David W. Taylor Naval Ship Research and Development Center in 1969 by enrolling in the Cooperative Education Program at the Annapolis laboratory. He earned a Bachelor of Science degree in chemical engineering in 1973 at West Virginia Institute of Technology. Daniel A. Groghan:received a Bachelor of Science degree in mechanical engineering from West Virginia Institute of Technology in 1966 and later did graduate work at the George Washington University and the University of Maryland. He came to the Naval Ship Systems Command in June 1966 and began working in the Internal Combustion and Gas Turbine Engines Branch. He worked on development of the Orenda OT-4 recuperated gas turbine and marinization of the Garrett 831 gas turbine. He was also project engineer responsible for fleet installations and product improvements on the Solar Saturn gas turbines Boeing gas turbines American Locomotive diesels Electro-Motive diesels and Ruston Pax-man diesels. In 1976 he became head of the Engines Research and Development Branch where he was responsible for such programs as development of hot section gas turbine materials improved gas turbine inlets Pratt and Whitney FT9 gas turbine General Electric LM2500 Condition Monitor and initiation of the RACER program. In 1982 he became the Program Manager for propulsion systems development where he is responsible for developments on the DDG-51 AOE-6 and initiation of the recuperated cruise gas turbine.

Investigations are currently being conducted by the Navy and several contractors to determine the technical feasibility and cost effectiveness of advanced regenerative or intercooled-regenerative gas turbines as a naval propulsion engine for future mid-size surface combatants. A comparison of the performance characteristics of these engines indicates that significant increases in the thermal efficiency above current simple-cycle engines will result by adding heat exchangers for regeneration alone or with intercooling. Design and performance characteristics of several advanced-cycle gas turbines are described which utilize turbomachinery from various existing simple-cycle gas turbines. Estimates of the weight and volume of recuperators and intercoolers for these conceptual engines are provided. The nominal part-load fuel consumption trends of the simple-cycle and the advanced-cycle engines are used to compare annual fuel usage of typical ships with various combinations of propulsion engines. The relative impacts of the advanced-cycle gas turbine on propulsion machinery spaces are compared with other energy efficient prime movers using the simple-cycle gas turbine as the baseline. Commercial applications for an advanced-cycle gas turbine are surveyed according to output power and market sector. This paper presents an overview of current results and discusses the technology areas which require additional investigation.

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RATIONALE FOR AN ADA SOFTWARE engineering ENVIRONMENT FOR NAVY MISSION CRITICAL APPLICATIONS

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NAVAL ENGINEERS JOURNAL 1984年第4期96卷 133-145页

作者： PAIGE, KK CONVERSE, RA USN LCdr. Kathleen K. Paige USN:graduated with a BA from the University of New Hampshire in 1970. She received her commission from Officer Candidate School in April 1971 and performed her first tour of duty with VFP-63 NAS Miramar. LCdr. Paige then received her MS from the Naval Post Graduate School in June 1976 and returned to San Diego to serve as Head Support Software Division at the Fleet Combat Direction System Support Activity. In May 1981 she reported to NA VSEA (PMS-408) where she served initially as Chairman of the NAVMAT Software Engineering Environment Working Group. She has been assigned as Deputy AN/UYK-43 Acquisition Manager since October 1981. LCdr. Paige was designated a fully qualified Engineering Duty Officer in December 1983. Robert A. Converse:is presently the Acquisition Manager for the Ada Language System/Navy (ALS/N) for the Naval Sea Systems Command Tactical Embedded Computer Resources Project. As such he is responsible for the definition and development of the ALS/N to be provided as a Navy standard computer programming system for Navy mission critical applications. Mr. Converse received a Bachelor of Science degree in Physics from Wheaton College Wheaton II. He spent fourteen years with the Naval Underwater Systems Center Newport Rhode Island during which time he designed and developed the Fortran compiler for the Navy Standard AN/UYK-7 computer. Also during that period he received a Master of Science degree in Computer Science from the University of Rhode Island. His thesis for that degree was entitled “Optimization Techniques for the NUSC Fortran Cross-Compiler”. Mr. Converse started his involvement with the Ada program in 1975 with the initial “Strawman” requirements review. Subsequently he was named as the Navy Ada Distinguished Reviewer and was intimately involved in the selection and refinement of the Ada language as it evolved to become ANSI/MIL-STD-1815A.

The U.S. Navy introduced the use of digital computers in mission critical applications over a quarter of a century ago. Today, virtually every system in the current and planned Navy inventory makes extensive use of computer technology. Computers embedded in mission critical Navy systems are integral to our strategic and tactical defense capabilities. Thus, the military power of the U.S. Navy is inextricably tied to the use of programmable digital computers. The computer program is the essential element that embodies the system “intelligence”. In addition, it provides the flexibility to respond to changing threats and requirements. However, this very flexibility and capability poses a host of difficulties hindering full realization of the advantages. This paper describes the lessons learned about computer program development over the past twenty five years and discusses a software engineering process that addresses these lessons. It then describes how Ada and its related Ada programming Support and Run-Time Environments foster this software engineering process to improve computer program productivity and achieve greater system reliability and adaptibility. Finally, the paper discusses how the use of Ada and its environments can enhance the interoperability and transferability of computer programs among Navy projects and significantly reduce overall life cycle costs for Navy mission critical computer programs.

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