Development of Radon-222 as Natural Tracer for Monitoring the Remediation of NAPL in the Subsurface (open access)

Development of Radon-222 as Natural Tracer for Monitoring the Remediation of NAPL in the Subsurface

Naturally occurring 222-radon in ground water can potentially be used as an in situ partitioning tracer to characterize dense nonaqueous phase liquid (DNAPL) saturations. The static method involves comparing radon concentrations in water samples from DNAPL-contaminated and non-contaminated portions of an aquifer. During a push-pull test, a known volume of test solution (radon-free water containing a conservation tracer) is first injected (''pushed'') into a well; flow is then reversed and the test solution/groundwater mixture is extracted (''pulled'') from the same well. In the presence of NAPL radon transport is retarded relative to the conservative tracer. Assuming linear equilibrium partitioning, retardation factors for radon can be used to estimate NAPL saturations.The utility of this methodology was evaluated in laboratory and field settings.
Date: February 27, 2003
Creator: Davis, Brian M.; Semprini, Lewis & Istok, Jonathan
System: The UNT Digital Library
21-PWR Waste Package Side and End Impacts (open access)

21-PWR Waste Package Side and End Impacts

The objective of this calculation is to determine the structural response of a 21-Pressurized Water Reactor (PWR) spent nuclear fuel waste package impacting an unyielding surface. A range of initial velocities and initial angles between the waste package and the unyielding surface is studied. The scope of this calculation is limited to estimating the area of the outer shell (OS) where the residual stress exceeds a given limit (hereafter ''damaged area''). The stress limit is defined as a fraction of the yield strength of the OS material, Alloy 22 (SB-575 N06022), at the appropriate temperature. The design of the 21-PWR waste package used in this calculation is that defined in Reference 8. However, a value of 4 mm was used for the gap between the inner shell and the OS, and the thickness of the OS was reduced by 2 mm. The sketch in Attachment I provides additional information not included in Reference 8. All obtained results are valid for this design only. This calculation is associated with the waste package design and was performed by the Specialty Analyses and Waste Package Design Section. The waste package (i.e. uncanistered spent nuclear fuel disposal container) is classified as Quality Level 1.
Date: February 27, 2003
Creator: Delabrosse, V.
System: The UNT Digital Library
Gas Main Sensor and Communications Network System: Phase I Topical Report (open access)

Gas Main Sensor and Communications Network System: Phase I Topical Report

Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the New York Gas Group (NYGAS), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. A prototype system was built for low-pressure cast-iron mains and tested in a spider- and serial-network configuration in a live network in Long Island with the support of Keyspan Energy, Inc. The prototype unit combined sensors capable of monitoring pressure, flow, humidity, temperature and vibration, which were sampled and combined in data-packages in an in-pipe master-slave architecture to collect data from a distributed spider-arrangement, and in a master-repeater-slave configuration in serial or ladder-network arrangements. It was found that the system was capable of performing all data-sampling and collection as expected, yielding interesting results as to flow-dynamics and vibration-detection. Wireless in-pipe communications were shown to be feasible and valuable data was collected in order to determine how to improve on range and data-quality in the future.
Date: February 27, 2003
Creator: Hagen Schempf, Ph.D.
System: The UNT Digital Library
IMPROVEMENT OF WEAR COMPONENT'S PERFORMANCE BY UTILIZING ADVANCED MATERIALS AND NEW MANUFACTURING TECHNOLOGIES: CASTCON PROCESS FOR MINING APPLICATIONS (open access)

IMPROVEMENT OF WEAR COMPONENT'S PERFORMANCE BY UTILIZING ADVANCED MATERIALS AND NEW MANUFACTURING TECHNOLOGIES: CASTCON PROCESS FOR MINING APPLICATIONS

The project was highlighted by continued fabrication of drill bit inserts and testing them: (1) The inserts were subjected to hammer tests to determine brittleness. Selected inserts experienced multiple blows from a 16 pound sledge hammer. The resulting damage was minimal. (2) Three inserts were placed on three different 16.5 inch diameter rotary drill bits, and the bits drilled taconite rock until the entire bit failed. (3) The inserts had somewhat less wear resistance than current art, and exhibited no brittle failures. (4) More work is needed to produce the inserts at near net shape. The test inserts required too much machining. The project next turned to manufacturing 6.5 inch diameter disc cutters. The cutters will feature a core of tungsten carbide (TC) in a disc body composed of H13 tool steel. The TC inserts are in manufacture and the dies for the disc are being designed. The plan for next quarter: (1) Investigate materials and manufacturing changes for the fibrous monolith drill bit inserts that will increase their wear life. (2) Begin manufacturing disc cutters.
Date: February 27, 2003
Creator: Huang, Xiaodi & Gertsch, Richard
System: The UNT Digital Library
Optical Fiber Sensor Technologies for Efficient and Economical Oil Recovery (open access)

Optical Fiber Sensor Technologies for Efficient and Economical Oil Recovery

The overall goal of this project was to develop reliable cost effective sensors for application in the down-hole environment. The physical parameters measured by these sensors were temperature, pressure, flow and acoustic signals. Sensor head configurations for each of the physical measurands were optimized to increase the sensitivity to the particular measurand of interest while decreasing the cross-sensitivity to the other physical measurands and to environmental influences. In addition, the optical signal demodulation electronics was designed to be insensitive to environmental influences while maintaining the required resolution, precision and accuracy of the parameter being sensed. The influence of potentially detrimental agents such as water in the down-hole environment was investigated as well as methods to protect both the optical fiber and the sensor from these detrimental effects.
Date: February 27, 2003
Creator: Wang, a.; Pickrell, G.; Xiao, H. & May, r.
System: The UNT Digital Library