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Showing 1 to 13 of 13 for “"tracer gases"”.
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Design of an Experimental Mine Simulator for the Development of a Procedure for Utilization Multiple Tracer Gases in Underground Mines
… was constructed which will be used to conduct tracer gas experiments in the laboratory. The test apparatus simulates a mine in a tabular deposit and is modular and simple and can be easily rearranged to represent a variety of mine geometries. The apparatus is appropriate for the use of tracer …
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The Assessment of Sonic Waves and Tracer Gases as Non-Destructive Testing (NDT) Methods for In-Situ Underground Mine Seals
… in this case, are explored using sonic waves and tracer gases. Through both small and large scale testing, two NDT methods were evaluated on their abilities to determine integrity of the seal. A sonic wave technique to observe a change in wave velocity to identify faults within the seal material. …
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Determination of a novel mine tracer gas and development of a methodology for sampling and analysis of multiple mine tracer gases for characterization of ventilation systems
… rescue personnel into the mine. By utilizing tracer gas techniques, which are powerful techniques for monitoring ventilation systems, especially in remote or inaccessible areas, analysis of the ventilation system immediately following a mine emergency can be more rapidly ascertained. However, …
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A study of the controllability of air movements in predominantly naturally ventilated houses.
… difference. The method of measurement uses tracer gases which are injected into spaces and their growths and decays are monitored. These concentration histories, when suitably analysed, reveal the interzonal airflow rate. Empirical formulae describing the interzonal airflow rate as a …
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Development of a remote analysis method for underground ventilation systems using tracer gas and CFD
… This study developed a methodology that uses tracer gas techniques and CFD modeling to analyze underground mine ventilation system status remotely. After an unanticipated event that has damaged ventilation controls, the first step of the methodology is to assess and estimate the level of the …
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Spatial and Temporal Distribution of Speciated Atmospheric Mercury in Southeastern Texas
… 2013-June 6, 2013, respectively. The use of key tracer gases from various data sources as well as meteorological data from ground-based stationary monitoring facilities was used in the evaluation of high-mercury pollution plumes, the general direction of the source origin as well as seasonal and …
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Development and Evaluation of a Permeation Plug Release Vessel (PPRV) for the Release of Perfluoromethylcyclohexane (PMCH) in Underground Mine Tracer Gas Studies
The use of sulfur hexafluoride (SF6) as a tracer gas for analyzing underground mine ventilation systems has been practiced for over 30 years. As a result, the methods used to release, sample, and analyze SF6 are well accepted. Although improvements are still being made to enhance the analysis of …
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INVESTIGATION OF TRACER GAS VARIABILITY FROM OBSERVATIONS AND MODELS
The variability of the tracer gases CO2 and ozone was investigated utilizing in-situ measurements, satellite retrievals, and model simulations. In the tropical region, using Atmospheric Infrared Sounder (AIRS) mid-tropospheric CO2 retrievals led to the discovery of a signal with a periodicity of …
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A detailed justification for the selection of a novel mine tracer gas and development of protocols for GC-ECD analysis of SPME sampling in static and turbulent conditions for assessment of underground mine ventilation systems
Tracer gas surveys are a powerful means of assessing air quantity in underground mine ventilation circuits. The execution of a tracer gas style ventilation survey allows for the direct measurement of air quantity in locations where this information is otherwise unattainable. Such instances include …
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Approaches to Simulation of an Underground Longwall Mine and Implications for Ventilation System Analysis
… longwall mine, especially for the use of tracer gas in an emergency situation. In an emergency situation, limited information about the state of mine ventilation system is known, and it is difficult to make informed decisions about safety of the mine for rescue personnel. With careful …
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Monitoring for Enhanced Gas and Liquids Recovery from a CO2 'Huff-and-Puff' Injection Test in a Horizontal Chattanooga Shale Well
… phases of the test. Multiple fluorinated tracers were used to monitor for potential CO2 breakthrough at offset production wells and to help account for the CO2 once the well was flowed back. Results from this test, once the well was put back into normal production state, confirm the …
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The Measurement of Decomposition Products of Select Gases as an Indicator of a Concealed Mine Fire
… have been selected for use as 'fire indicator gases' with the acronym of 'FIGs.' These two compounds are: 1. C6-Perfluoroketone (CF3CF2C(=O)CF(CF3)2 ) 2. 1,1 Difluoroethane (CH3CHF2) This study provides suggestions as to how to look for other potential FIGs, and how to improve the testing of …
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A Computational Model of Inert Gas Mixing in the Lung
Inert gases are used as markers or contrast agents in experimental and imaging methods that measure lung function. The premise is that by analysing the expired concentrations of inert gas, or by quantifying their distribution from \textit{in vivo} imaging, information can be gained about the …