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Novel electrocatalytic sensors

Description: Basic principles employed for previously developed oxygen and SO{sub 2} sensors have been applied to other chemical sensor needs. Oxide electrodes used for oxygen sensors also possess novel catalytic properties that have been utilized for CO detection through the use of electrocatalysts on solid electrolyte membranes. These oxides offer the ability to catalyze reactions selectively for oxidation and/or reduction of analyte gas species. A combination of a catalytic and noncatalytic electrode deposited on a solid electrolyte was used to sense the reactive species by locally changing the oxygen concentration on the electrode surfaces. Multiple species can be sensed on a single substrate through the use of different electrocatalysts. A related concept is to control the catalytic properties of these materials by controlling the oxygen stoichiometry using an electrochemical pump. Presence of a gas species was sensed by changes in the electronic conductivity of the semiconducting electrode layer.
Date: November 1, 1996
Creator: Garzon, F. & Brosha, E.
Partner: UNT Libraries Government Documents Department

Sampling and Analysis Procedures for Gas, Condensate, Brine, and Solids: Pleasant Bayou Well Test, 1988-Present

Description: This section covers analyses performed on gas. Chemical analyses can only be related to well performance if the quantity of the various fluids are known. The IGT on-line data computer system measures the flowrate, the pressures, and the temperatures every 10 seconds. These values are automatically recorded over operator selected intervals both on magnetic media and on paper. This allows review of samples versus operating conditions. This paper covers analyses performed on gas, including: An approximate sampling schedule during flow tests; On-site sample handling and storage of gas samples; Addresses of laboratories that perform off site analyses; Sample shipping instructions; Data archiving; and Quality Control/Quality Assurance. It is expected that the above procedures will change as the flow test progresses, but deviations from the written procedures should be approved by C. Hayden of IGT and noted on the results of the analysis.
Date: January 1, 1988
Creator: Hayden, Chris
Partner: UNT Libraries Government Documents Department

Multiplexed gas spectroscopy using tunable VCSELs

Description: Detection and identification of gas species using tunable laser diode laser absorption spectroscopy has been performed using vertical cavity surface emitting lasers (VCSEL). Two detection methods are compared: direct absorbance and wavelength modulation spectroscopy (WMS). In the first, the output of a DC-based laser is directly monitored to detect for any quench at the targeted specie wavelength. In the latter, the emission wavelength of the laser is modulated by applying a sinusoidal component on the drive current of frequency {omega}, and measuring the harmonics component (2{omega}) of the photo-detected current. This method shows a better sensitivity measured as signal to noise ratio, and is less susceptible to interference effects such as scattering or fouling. Gas detection was initially performed at room temperature and atmospheric conditions using VCSELs of emission wavelength 763 nm for oxygen and 1392 nm for water, scanning over a range of approximately 10 nm, sufficient to cover 5-10 gas specific absorption lines that enable identification and quantization of gas composition. The amplitude and frequency modulation parameters were optimized for each detected gas species, by performing two dimensional sweeps for both tuning current and either amplitude or frequency, respectively. We found that the highest detected signal is observed for a wavelength modulation amplitude equal to the width of the gas absorbance lines, in good agreement with theoretical calculations, and for modulation frequencies below the time response of the lasers (<50KHz). In conclusion, we will discuss limit of detection studies and further implementation and packaging of VCSELs in diode arrays for continuous and simultaneous monitoring of multiple species in gaseous mixtures.
Date: April 10, 2012
Creator: Bond, T; Bond, S; McCarrick, J; Zumstein, J; Chang, A; Moran, B et al.
Partner: UNT Libraries Government Documents Department

HEADSPACE GAS EVALUATION OF WELDED PLUTONIUM STORAGE CONTAINERS

Description: The Can Puncture Device (CPD) serves as a containment vessel during the puncture of nested 3013 containers as part of surveillance operations in K-Area. The purpose of the CPD sampling process is to determine the original pressure and composition of gases within the inner 3013 container. The relation between the composition of the gas sample drawn from the CPD and that originally in the inner 3013 container depends on the degree of mixing that occurs over the interval of time from the puncture to drawing the sample. Gas mixing is bounded by the extremes of no mixing of gases in the inner container and that of complete mixing, in which case the entire CPD system is of uniform composition. Models relating the sample composition and pressure to the initial (pre-puncture) inner can composition and pressure for each of these extremes were developed. Predictions from both models were compared to data from characterization experiments. In the comparison, it was found that the model that assumed complete gas mixing after puncture, the Uniform Mixing Model, showed significantly better agreement with the data than the model that assumed no change in the composition of the inner container, referred to as the Non-Uniform Mixing Model. Both models were implemented as Microsoft{reg_sign} Excel spreadsheet calculations, which utilize macros, to include the effects of uncertainties and biases in the measurements of process parameters and in the models. Potential inleakage of gas from the glovebox is also addressed. The spreadsheet utilizing the Uniform Mixing Model, which was validated by data from the characterization tests, is used to evaluate the pre-puncture composition and pressure within the inner 3013 container. This spreadsheet model is called the Gas Evaluation Software Tool (GEST).
Date: April 1, 2008
Creator: Hardy, B; Stephen Harris, S; Matthew Arnold, M & Steve Hensel, S
Partner: UNT Libraries Government Documents Department

Statistics for the Relative Detectability of Chemicals in Weak Gaseous Plumes in LWIR Hyperspectral Imagery

Description: The detection and identification of weak gaseous plumes using thermal imaging data is complicated by many factors. These include variability due to atmosphere, ground and plume temperature, and background clutter. This paper presents an analysis of one formulation of the physics-based model that describes the at-sensor observed radiance. The motivating question for the analyses performed in this paper is as follows. Given a set of backgrounds, is there a way to predict the background over which the probability of detecting a given chemical will be the highest? Two statistics were developed to address this question. These statistics incorporate data from the long-wave infrared band to predict the background over which chemical detectability will be the highest. These statistics can be computed prior to data collection. As a preliminary exploration into the predictive ability of these statistics, analyses were performed on synthetic hyperspectral images. Each image contained one chemical (either carbon tetrachloride or ammonia) spread across six distinct background types. The statistics were used to generate predictions for the background ranks. Then, the predicted ranks were compared to the empirical ranks obtained from the analyses of the synthetic images. For the simplified images under consideration, the predicted and empirical ranks showed a promising amount of agreement. One statistic accurately predicted the best and worst background for detection in all of the images. Future work may include explorations of more complicated plume ingredients, background types, and noise structures.
Date: October 30, 2008
Creator: Metoyer, Candace N.; Walsh, Stephen J.; Tardiff, Mark F. & Chilton, Lawrence
Partner: UNT Libraries Government Documents Department

Vapor and gas sampling of single-shell tank 241-U-104 using the in situ vapor sampling system

Description: The Vapor Issue.Resolution Program tasked the Vapor Team (VT) to collect representative headspace samples from Hanford Site single-shell tank (SST) 241-U-104. This document presents In Situ Vapor Sampling System (ISVS) data resulting from the July 16, 1996 sampling of SST 241-U-104. Analytical results will be presented in separate reports issued by the Pacific Northwest National Laboratory (PNNL) which supplied and analyzed the sample media.
Date: August 5, 1997
Creator: Lockrem, L.L.
Partner: UNT Libraries Government Documents Department

Retained gas sampler interim safety assessment

Description: This safety assessment addresses the proposed action to install, operate, and remove a Retained Gas Sampler (RGS) in Tank 101-SY at Hanford. Purpose of the RGS is to help characterize the gas species retained in the tank waste; the information will be used to refine models that predict the gas-producing behavior of the waste tank. The RGS will take samples of the tank from top to bottom; these samples will be analyzed for gas constituents. The proposed action is required as part of an evaluation of mitigation concepts for eliminating episodic gas releases that result in high hydrogen concentrations in the tank dome space.
Date: January 13, 1995
Creator: Pasamehmetoglu, K.O.; Miller, W.O.; Unal, C. & Fujita, R.K.
Partner: UNT Libraries Government Documents Department

Vapor and gas sampling of single-shell tank 241-C-107 using the vapor sampling system

Description: The Vapor Issue Resolution Program tasked the Vapor Team (the team) to collect representative headspace samples from Hanford Site single-shell tank (SST) 241-C-107. This document presents sampling data resulting from the March 26, 1996 sampling of SST 241-C-107. Analytical results will be presented in separate reports issued by the Pacific Northwest National Laboratory which supplied and analyzed the sample media. The team collected representative headspace samples using the In Situ Vapor Sampling System (ISVS).
Date: August 5, 1997
Creator: Lockrem, L.L.
Partner: UNT Libraries Government Documents Department

Gas Composition Transients in the Cold Vacuum Drying (CVD) Facility

Description: The purpose of this document is to evaluate selected problems involving the prediction of transient gas compositions during Cold Vacuum Drying operations. The problems were evaluated to answer specific design questions. The document is formatted as a topical report with each section representing a specific problem solution. The problem solutions are reported in the calculation format specified in HNF-1613, Rev. 0, EP 7.6.
Date: May 10, 2000
Creator: PACKER, M.J.
Partner: UNT Libraries Government Documents Department

Tank 241-BY-107 headspace gas and vapor characterization results for samples collected in March 1994 and October 1994

Description: Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories.
Date: September 1, 1995
Creator: Huckaby, J.L. & Bratzel, D.R.
Partner: UNT Libraries Government Documents Department

Vapor and gas sampling of single-shell tank 241-C-201 using the in situ vapor sampling system

Description: The Vapor Issue Resolution Program tasked the Vapor Team (VT) to collect representative headspace samples from Hanford Site single-shell tank (SST) 241-C-201. This document presents In Situ Vapor Sampling System (ISVS) data resulting from the June 19, 1996 sampling of SST 241-C-201. Analytical results will be presented in separate reports issued by the Pacific Northwest National Laboratory (PNNL) which supplied and analyzed the sample media.
Date: August 5, 1997
Creator: Lockrem, L.L.
Partner: UNT Libraries Government Documents Department

Vapor and gas sampling of single-shell tank 241-C-202 using the in situ vapor sampling system

Description: The Vapor Issue Resolution Program tasked the Vapor Team (VT) to collect representative headspace samples from Hanford Site single-shell tank (SST) 241-C-202. This document presents In Situ Vapor Sampling System (ISVS) data resulting from the June 25, 1996 sampling of SST 241-C-202. Analytical results will be presented in separate reports issued by the Pacific Northwest National Laboratory (PNNL) which supplied and analyzed the sample media.
Date: August 8, 1997
Creator: Lockrem, L.L.
Partner: UNT Libraries Government Documents Department

Flammable gas tank waste level reconcilliation for 241-SX-102

Description: Fluoro Dynel Northwest (FDNW) was authorized to address flammable gas issues by reconciling the unexplained surface level increases in Tank 24 1-S-1 1 1 (S-I 1 1, typical). The trapped gas evaluation document (ref 1) states that Tank SX-102 exceeds the 25% of the lower flammable limit (FL) criterion (ref 2), based on a surface level rise evaluation. The Waste Storage Tank Status and Leak Detection Criteria document, commonly referred to as the ``Wallet Report`` is the basis for this letter report (ref 3). The Wallet Report is also a part of the trapped gas evaluation document criteria. The Wallet Report contains various tank information, including: physical information, status, levels, and dry wells, see Appendix A. The unexplained waste level rises were attributed to the production and retention of gas in the column of waste corresponding to the unacquainted for surface level rise. From 1973 through 1980, the Wallet Report tracked Tank S- 102 transfers and reported a net cumulative change of 19.95 in. This surface level increase is from an unknown source or is unacquainted for. Duke Engineering and Services Hanford (DASH) and Leached Martin Hanford Corporation (LMHC) are interested in determining the validity of the unexplained surface level changes reported in the 0611e Wallet Report based upon other corroborative sources of data. The purpose of this letter report is to assemble detailed surface level and waste addition data from daily tank records, logbooks, and other corroborative data that indicate surface levels, and to reconcile the cumulative unacquainted for surface level changes as shown in the Wallet Report from 1973 through 1980.
Date: June 23, 1997
Creator: Brevick, C.H. & Gaddie, L.A.
Partner: UNT Libraries Government Documents Department

Results of vapor space monitoring of flammable gas Watch List tanks

Description: This report documents the measurement of headspace gas concentrations and monitoring results from the Hanford tanks that have continuous flammable gas monitoring. The systems used to monitor the tanks are Standard Hydrogen Monitoring Systems. Further characterization of the tank off-gases was done with Gas Characterization Systems and vapor grab samples. The background concentrations of all tanks are below the action level of 6250 ppm. Other information which can be derived from the measurements (such as generation rate, release rate, and ventilation rate) is also discussed.
Date: September 18, 1997
Creator: Wilkins, N.E.
Partner: UNT Libraries Government Documents Department

Vapor and gas sampling of single-shell tank 241-C-204 using the in situ vapor sampling system

Description: The Vapor Issue Resolution Program tasked the Vapor Team (VT) to collect representative headspace samples from Hanford Site single-shell tank (SST) 241-C-204. This document presents In Situ Vapor Sampling System (ISVS) data resulting from the July 2, 1996 sampling of SST 241-C-204. Analytical results will be presented in separate reports issued by the Pacific Northwest National Laboratory (PNNL) which supplied and analyzed the sample media.
Date: August 5, 1997
Creator: Lockrem, L.L.
Partner: UNT Libraries Government Documents Department

Vapor and gas sampling of single-shell tank 241-B-105 using the in situ vapor sampling system

Description: The Vapor Issue Resolution Program tasked the Vapor Team (VT) to collect representative headspace samples from Hanford Site single-shell tank (SST) 241-B-105. This document presents In Situ Vapor Sampling System (ISVS) data resulting from the July 30, 1996 sampling of SST 241-B-105. Analytical results will be presented in separate reports issued by the Pacific Northwest National Laboratory (PNNL) which supplied and analyzed the sample media.
Date: August 5, 1997
Creator: Lockrem, L.L.
Partner: UNT Libraries Government Documents Department

Vapor and gas sampling of single-shell tank 241-T-104 using the in situ vapor sampling system

Description: The Vapor Issue Resolution Program tasked the Vapor Team (the team) to collect representative headspace samples from Hanford Site single-shell tank (SST) 241-T-104. This document presents sampling data resulting from the February 7, 1996 sampling of SST 241-T-104. Analytical results will be presented in separate reports issued by the laboratories that supplied and analyzed the sampling media.
Date: August 8, 1997
Creator: Lockrem, L.L.
Partner: UNT Libraries Government Documents Department

Vapor and gas sampling of single-shell tank 241-B-102 using the in situ vapor sampling system

Description: The Vapor Issue Resolution Program tasked the Vapor Team (the team) to collect representative headspace samples from Hanford Site single-shell tank (SST) 241-B-102. This document presents sampling data resulting from the April 18, 1996 sampling of SST 241-B-102. Analytical results will be presented in a separate report issued by Pacific Northwest National Laboratory (PNNL), which supplied and analyzed the sampling media. The team, consisting of Sampling and Mobile Laboratories (SML) and Special Analytical Studies (SAS) personnel, used the vapor sampling system (VSS) to collect representative samples of the air, gases, and vapors from the headspace of SST 241-B-102 with sorbent traps and SUMMA canisters.
Date: August 5, 1997
Creator: Lockrem, L.L.
Partner: UNT Libraries Government Documents Department

Vapor and gas sampling of single-shell tank 241-BX-103 using the in situ vapor sampling system

Description: The Vapor Issue Resolution Program tasked the Vapor Team (VT) to collect representative headspace samples from Hanford Site single-shell tank (SST) 241-BX-103. This document presents In Situ Vapor Sampling System (ISVS) data resulting from the August 1, 1996 sampling of SST 241-BX-103. Analytical results will be presented in separate reports issued by the Pacific Northwest National Laboratory (PNNL) which supplied and analyzed the sample media.
Date: August 5, 1997
Creator: Lockrem, L.L.
Partner: UNT Libraries Government Documents Department