System Operational Evaluation of Mine Monitoring Systems

In the testing of mine monitoring systems, a software package was developed for the mine monitoring test facility designed at West Virginia University. The software establishes delay times of sensor input to annunciation for single alarms and multiple simultaneous alarms. The alarm measurement techniques for the test fixture are described, as is the software developed to analyze and graph monitoring system response data. Also included is the analysis capability of the facility, the criteria for evaluating mine monitoring systems, and typical test data from a sample system.     

Sintered Halon as a diffuse reflecting liner for light integration boxes

Sintered Halon G-80, a polytetrafluoroethylene (PTFE) resin available commercially in powdered form, is a superb diffuse reflector. Sintered Halon has 96% absolute reflectance at wavelengths between 300 nm and 380 nm, and about 98% absolute reflectance above 380 nm. It is chemically inert, is mechanically strong, does not fluoresce, and the high reflectance is easy to maintain over time. We have used sintered Halon as a lining in light integration boxes of water Cherenkov detectors. Preparation involves packing Halon powder into a mold to a specific density, then heating the material almost to the melting point (sintering). A method of preparing sintered Halon is presented. Physical properties of sintered Halon have been measured and we present those results here as well.     

Leading-edge separation from a thick,conical, slender wing at small angless of incidence

Summary The inviscid separated flow past slender rhombic cones at incidence is considered. A complex potential is constructed, in a suitable cross-flow plane, which satisfies the conditions on the wing, at infinity, and on the vortex system which models the separated flow. The results obtained both extend earlier results to small incidence, and explain an anomaly within those results.     

Determination of the structure of lecithins via the formation of acetylated 1,2-diglycerides

A detailed procedure for quantitative determinations of molecular species of lecithins is described and applied to several lecithins isolated from natural sources. The method is based on the conversion of lecithin to acetylated 1,2-diglycerides and analysis of these compounds by methodology used for the determination of triglyceride structure. The preparation of the acetylated 1,2-diglycerides was carried out via hydrolysis with phospholipase C and acetylation of the resultant, 1,2-diglycerides with pyridine-acetic anhydride. Preparation of acetylated 1,2-diglycerides from lecithin by acetolysis with acetic acid-acetic anhydride was shown to be accompanied by intermolecular as well as intramolecular rearrangement of the fatty acids. The structure of the acetylated 1,2-diglycerides was determined by a combination of argentation-TLC and pancreatic lipase hydrolysis using internal standards for quantification. The method was applied to lecithins isolated from milk serum, egg, soybean, safflower seed and wheat germ lipids.     

Computer simulation of energy use,greenhouse gas emissions,and costs for alternative methods of processing fluid milk

Computer simulation is a useful tool for benchmarking electrical and fuel energy consumption and water use in a fluid milk plant. In this study, a computer simulation model of the fluid milk process based on high temperature, short time (HTST) pasteurization was extended to include models for processes for shelf-stable milk and extended shelf-life milk that may help prevent the loss or waste of milk that leads to increases in the greenhouse gas (GHG) emissions for fluid milk. The models were for UHT processing, crossflow microfiltration (MF) without HTST pasteurization, crossflow MF followed by HTST pasteurization (MF/HTST), crossflow MF/HTST with partial homogenization, and pulsed electric field (PEF) processing, and were incorporated into the existing model for the fluid milk process. Simulation trials were conducted assuming a production rate for the plants of 113.6 million liters of milk per year to produce only whole milk (3.25%) and 40% cream. Results showed that GHG emissions in the form of process-related CO₂ emissions, defined as CO₂ equivalents (e)/kg of raw milk processed (RMP), and specific energy consumptions (SEC) for electricity and natural gas use for the HTST process alone were 37.6 g of CO₂e/kg of RMP, 0.14 MJ/kg of RMP, and 0.13 MJ/kg of RMP, respectively. Emissions of CO₂ and SEC for electricity and natural gas use were highest for the PEF process, with values of 99.1 g of CO₂e/kg of RMP, 0.44 MJ/kg of RMP, and 0.10 MJ/kg of RMP, respectively, and lowest for the UHT process at 31.4 g of CO₂e/kg of RMP, 0.10 MJ/kg of RMP, and 0.17 MJ/kg of RMP. Estimated unit production costs associated with the various processes were lowest for the HTST process and MF/HTST with partial homogenization at $0.507/L and highest for the UHT process at $0.60/L. The increase in shelf life associated with the UHT and MF processes may eliminate some of the supply chain product and consumer losses and waste of milk and compensate for the small increases in GHG emissions or total SEC noted for these processes compared with HTST pasteurization alone. The water use calculated for the HTST and PEF processes were both 0.245 kg of water/kg of RMP. The highest water use was associated with the MF/HTST process, which required 0.333 kg of water/kg of RMP, with the additional water required for membrane cleaning. The simulation model is a benchmarking framework for current plant operations and a tool for evaluating the costs of process upgrades and new technologies that improve energy efficiency and water savings.     

Invited review: Environmental impacts of dairy processing and products: a review

The objective of this review is to summarize research efforts and case studies to date of the environmental impacts from dairy processing. The pervasiveness of greenhouse gas emission, water use, consumer waste, and other environmental impacts of dairy are described. An outline of the method of choice, the life cycle assessment, for conducting research and deciding appropriate allocation of the impacts is provided. Specific research examples in dairy processing highlight how the representative final product is associated with environmental impacts to air, water, and land. The primary conclusion from the study was the usefulness of life cycle assessment methodology and the need for further research due to limited studies, variable data, and the magnitude of environmental impact.     

Test Criteria and Methodology for Evaluation of Coal Mine Monitoring and Control Systems

Field evaluation of coal mine monitoring and control systems yields data on installation and maintenance, but does not provide a full evaluation of these systems under all possible conditions. Also, the differences in installations and configurations do not allow the performance of different systems to be measured and compared. Under contract of the United States Bureau of Mines (USBM), the West Virginia University (WVU) Department of Electrical Engineering has designed criteria for evaluation of monitoring systems, and a test facility for simulation of mine conditions. This facility provides evaluation of monitoring and control systems under both normal and abnormal conditions. This paper describes the test criteria chosen, the design of the test facility, and the experiences of tests performed on mine monitoring systems to date.     

Detailed In Situ Hot Stage Transmission Electron Microscope Observations of the Localized Pinning of a Mobile Ferrite-Austenite Interface in a Fe-C-Mn Alloy by a Single Oxidic Particle

Metallurgical and Materials Transactions A - The current study reports the detailed analysis of an observation of the local pinning of a slowly moving austenite-ferrite interface by a single...     

Microstructure Evolution and Tensile Behaviour of a Cold Rolled 8 Wt Pct Mn Medium Manganese Steel

Metallurgical and Materials Transactions A - A novel medium manganese steel with composition Fe–8.3Mn–3.8Al–1.8Si–0.5C–0.06V–0.05Sn was developed and...     

An experimental study of axial conduction through a thermosyphon pipe wall

The effect of the axial conduction through the pipe wall on the performance of a thermosyphon was experimentally investigated in this study. Two 2-phase closed thermosyphons were tested; each had the same dimensions, materials and partially filled with R134a. The only difference between them was that one had a thermal break within the adiabatic section that resisted axial conduction between the evaporator and the condenser sections. The thermosyphons were heated by a constant-temperature hot bath and cooled by water via a concentric heat exchanger. The experiments were performed for different bath temperatures and different fill ratios. It was found that the axial conduction through the pipe wall caused an increase in the overall heat transfer coefficient, evaporation heat transfer coefficient and condensation heat transfer coefficient of the thermosyphon. However, the fraction of heat transfer associated with axial conduction decreased as the heat flux increased. For small heat flux (T_b = 30 °C), the increment of the evaporation and condensation heat transfer coefficient contributed by axial conduction reached 100% and 25%, respectively. For high heat flux (T_b = 60 °C), the increment was negligible (less than 1%).