Kentucky\u27s Coal Industry: Historical Trends and Future Opportunities

Coal has been produced in Kentucky since the late 18th century. In the early years, all mining was by underground methods, but surface mining became the dominant method during and after World War II. In recent years, surface-mine production in both fields has decreased while underground mining has increased. In the last half of this century, the traditional steam coal market for locomotives has virtually disappeared, leaving electric power generation and coking coal for the steel industry as the principal markets. More than half of all coal produced in the State has been produced in the last 25 years. Whether this level of production can be profitably sustained is questionable. More than 50 percent of the coal in eastern Kentucky is Jess than 28 in. thick, while more than 69 percent of the coal in western Kentucky is greater than 42 in. thick. Although eastern Kentucky\u27s resources are thinner, they have a lower sulfur content and higher calorific value than western Kentucky\u27s. Traditional resource estimates have overestimated the amount of coal that can actually be mined because they have not taken into account factors such as competing land uses and geologic and engineering constraints. KGS is participating in national programs to estimate coal availability and recoverability. Results of selected study areas suggest that as little as 50 percent of the original resource is available for mining, whereas only 20 percent is economically recoverable. It is uncertain yet whether these averages are indicative of all of Kentucky\u27s coal resources. Regional assessments of Kentucky\u27s most important coals, which incorporate coal availability methods, are under way. A number of regulatory and taxation issues will have an impact on the coal industry in Kentucky, but how much of an impact is uncertain. These issues include the Clean Air Act Amendments, liability for unreel aimed surface mines, regulatory flexibility to permit changes in postmine land use, and changes in the State\u27s workers\u27 compensation law. Advances in thin-seam and remote-mining technology will be crucial, particularly in eastern Kentucky, where most of the remaining coal occurs in thin seams. improvements in coal-preparation technology could make Kentucky\u27s higher sulfur coals more attractive. There may be potential for extraction of methane gas from coal beds, as an energy by-product. Detailed knowledge of the physical and chemical character of Kentucky\u27s coal beds will be vital in their development. Acquisition of this knowledge could be facilitated by cooperation among private industry, public agencies, and research institutes

SEPIA345: A 345 GHz dual polarization heterodyne receiver channel for SEPIA at the APEX telescope

Context. We describe the new SEPIA345 heterodyne receiver channel installed at the Atacama Pathfinder EXperiment (APEX) telescope, including details of its configuration, characteristics, and test results on sky. SEPIA345 is designed and built to be a part of the Swedish ESO PI Instrument for the APEX telescope (SEPIA). This new receiver channel is suitable for very high-resolution spectroscopy and covers the frequency range 272- 376 GHz. It utilizes a dual polarization sideband separating (2SB) receiver architecture, employing superconductor-isolator-superconductor mixers (SIS), and provides an intermediate frequency (IF) band of 4- 12 GHz for each sideband and polarization, thus covering a total instantaneous IF bandwidth of 4 \uc3\uc2 - 8 = 32 GHz. Aims. This paper provides a description of the new receiver in terms of its hardware design, performance, and commissioning results. Methods. The methods of design, construction, and testing of the new receiver are presented. Results. The achieved receiver performance in terms of noise temperature, sideband rejection, stability, and other parameters are described. Conclusions. SEPIA345 is a commissioned APEX facility instrument with state-of-the-art wideband IF performance. It has been available on the APEX telescope for science observations since July 2021

United States Geological Survey Reports

Report discussing the investigation of radioactivity in coal beds and associated rocks from the Pottsville, Allegheny, and Conemaugh formations in Beaver, Clearfield, and Jefferson counties, Pennsylvania. The report provides information regarding the procedures used, descriptive geology of the areas, radioactivity data, factors affecting the occurrence of radioactivity, and a summary

<title>Synchro-ballistic recording of detonation phenomena</title>

Synchro-ballistic use of rotating-mirror streak cameras allows for detailed recording of high-speed events of known velocity and direction. After an introduction to the synchro-ballistic technique, this paper details two diverse applications of the technique as applied in the field of high-explosives research. In the first series of experiments detonation-front shape is recorded as the arriving detonation shock wave tilts an obliquely mounted mirror, causing reflected light to be deflected from the imaging lens. These tests were conducted for the purpose of calibrating and confirming the asymptotic Detonation Shock Dynamics (DSD) theory of Bdzil and Stewart. The phase velocities of the events range from ten to thirty millimeters per microsecond. Optical magnification is set for optimal use of the film`s spatial dimension and the phase velocity is adjusted to provide synchronization at the camera`s maximum writing speed. Initial calibration of the technique is undertaken using a cylindrical HE geometry over a range of charge diameters and of sufficient length-to-diameter ratio to insure a stable detonation wave. The final experiment utilizes an arc-shaped explosive charge, resulting in an asymmetric detonation-front record. The second series of experiments consists of photographing a shaped-charge jet having a velocity range of two to nine millimeters per microsecond. To accommodate the range of velocities it is necessary to fire several tests, each synchronized to a different section of the jet. The experimental apparatus consists of a vacuum chamber to preclude atmospheric ablation of the jet tip with shocked-argon back lighting to produce a shadow-graph image

Synchro-Ballistic Recording of Detonation Phenomena

Synchro-ballistic use of rotating-mirror streak cameras allows for detailed recording of high-speed events of known velocity and direction. After an introduction to the synchro-ballistic technique, this paper details two diverse applications of the technique as applied in the field of high-explosives research. In the first series of experiments detonation-front shape is recorded as the arriving detonation shock wave tilts an obliquely mounted mirror, causing reflected light to be deflected from the imaging lens. These tests were conducted for the purpose of calibrating and confirming the asymptotic Detonation Shock Dynamics (DSD) theory of Bdzil and Stewart. The phase velocities of the events range from ten to thirty millimeters per microsecond. Optical magnification is set for optimal use of the film`s spatial dimension and the phase velocity is adjusted to provide synchronization at the camera`s maximum writing speed. Initial calibration of the technique is undertaken using a cylindrical HE geometry over a range of charge diameters and of sufficient length-to-diameter ratio to insure a stable detonation wave. The final experiment utilizes an arc-shaped explosive charge, resulting in an asymmetric detonation-front record. The second series of experiments consists of photographing a shaped-charge jet having a velocity range of two to nine millimeters per microsecond. To accommodate the range of velocities it is necessary to fire several tests, each synchronized to a different section of the jet. The experimental apparatus consists of a vacuum chamber to preclude atmospheric ablation of the jet tip with shocked-argon back lighting to produce a shadow-graph image

Proton radiography examination of unburned regions in PBX 9502 corner turning experiments

PBX 9502 Corner Turning Experiments have been used with various diagnostics techniques to study detonation wave propagation and the boosting of the insensitive explosive. In this work, the uninitiated region of the corner turning experiment is examined using Proton Radiography. Seven transmission radiographs obtained on the same experiment are used to map out the undetonated regions on each of three different experiments. The results show regions of high-density material, a few percent larger than initial explosive density. These regions persist at nearly this density while surrounding material, which has reacted, is released as expected. Calculations using Detonation Shock Dynamics are used to examine the situations that lead to the undetonated regions