Use of Limestone, Lime, and Dolomite for SO\u3csub\u3e2\u3c/sub\u3e Emission Control in Kentucky

Flue-gas desulfurization and atmospheric fluidized-bed combustion systems for sulfur dioxide (SO2) emission control have been installed at 13 coal- and gas-fired plants and one research laboratory in Kentucky. Limestone, lime, and dolomite are the principal SO2 sorbents used in these systems. Nine coal-fired, electricity-generating plants in the State have installed wet-scrubbing systems for flue-gas desulfurization. Lime-based scrubbers are using Thiosorbic® lime, produced from the Camp Nelson Limestone (Ordovician) of north-central Kentucky, and carbide lime, a byproduct from the manufacture of acetylene in Louisville. Limestone-based scrubbing systems at three of the plants have used stone from the Warsaw, Ste. Genevieve, and Paoli Limestones (Mississippian) of western and west-central Kentucky, southern Indiana, and southern Illinois. An experimental dry scrubber operated by the Tennessee Valley Authority uses lime produced from the Moccasin Formation (Ordovician) of eastern Tennessee. Limestone and dolomite are employed as SO2 sorbents in commercial, research, and demonstration atmospheric fluidized-bed combustion (AFBC) units. The New Market Limestone (Ordovician) from northern Virginia and a mixed sorbent consisting of Camp Nelson Limestone from north-central Kentucky and Peebles and Greenfield Dolomites (Silurian) from southern Ohio are used in steam-generating systems equipped with AFBC units at two commercial plants. Pilot and demonstration plants operated by the Tennessee Valley Authority to test and demonstrate utility-scale AFBC units have used Warsaw and Ste. Genevieve Limestones from western Kentucky. Dolomite from the Oregon Formation and limestone from the Grier Limestone Member of the Lexington Limestone, both Ordovician units in central Kentucky, have been used for tests of coals and alternate fuels in an industrial-size AFBC pilot plant, operated by the University of Kentucky and Kentucky Energy Cabinet. Pilot-plant tests have shown that other Kentucky dolomites (Silurian Laurel Dolomite and Mississippian Renfro Member of the Slade Formation) and limestones (Mississippian Salem and Warsaw Formations and Ste. Genevieve Limestone) also are effective AFBC sorbents

High-Carbonate and Low-Silica Stone in the High Bridge Group (Middle Ordovician), Fayette County, Central Kentucky

The High Bridge Group (Middle Ordovician) of central Kentucky, a major source of limestone and dolomite for construction and agricultural stone, is also a potential source of stone for industrial uses requiring carbonate rocks of high chemical purity. Chemical analyses of foot-by-foot samples from a Fayette County core show that several thick zones of high-carbonate and low-silica stone are present in the High Bridge at a minable depth

Tectonic Implications of Erosional and Depositional Features in Upper Meramecian and Lower Chesterian (Mississippian) Rocks of South-Central and East-Central Kentucky

Erosional and depositional features in upper Meramecian and lower Chesterian (Mississippian) carbonate rocks of south-central and east-central Kentucky suggest the influence of coeval structural activity. The study area, which extends from Pulaski County northeastward into Powell County, is underlain by (1) the Greenwood Anomaly, a large north-trending gravity anomaly, which probably represents part of a Precambrian rift system, and (2) the western part of the Rome Trough, an east-trending graben-like structure, which represents a Late Precambrian to Cambrian continental rift zone. The study focused on the St. Louis Limestone and lower Monteagle Limestone of south-central Kentucky and correlative carbonate rocks of the Slade Formation in east-central Kentucky. Several lines of evidence suggest Mississippian reactivation of rift-related faults associated with the Greenwood Anomaly and the Grenville Front, which extends along the west side of the anomaly: (1) local subaerial exposure of St. Louis sediments, (2) local depositional thinning of lower Monteagle sediments, (3) relatively widespread erosion during early Monteagle time, and (4) thickness variation in Mississippian units across the anomaly. In east-central Kentucky, erosional and depositional features suggest Mississippian movement along the Locust Branch and Glencairn Faults of the Irvine-Paint Creek Fault System in the interior of the Rome Trough during deposition of the Slade Formation. Reactivation along the projected trend of the Locust Branch Fault in Estill and Jackson Counties apparently resulted in (1) abrupt thinning of the Renfro Member, (2) penecontemporaneous soft-sediment deformation of Big Sinking bed deposits, and (3) extensive erosion of the Burnside member. Movement along the Glencairn Fault in Powell and Wolfe Counties is indicated by more pronounced erosion of the Burnside member along the border of the upthrown side. Mississippian reactivation of faults apparently was caused by migration of lithospheric bulges through the area. Based on recent investigations that relate Mississippian depositional sequence to lithospheric flexure, passage of an east-migrating, relaxation-phase, Acadian bulge and a north-migrating Ouachita bulge seems to have been contemporaneous with the fault movements and may explain evidence of fault reactivation and its consequences on Mississippian carbonate deposition in the area

Simulation of the synergistic low Earth orbit effects of vacuum thermal cycling, vacuum UV radiation, and atomic oxygen

In order to assess the low Earth orbit (LEO) durability of candidate space materials, it is necessary to use ground laboratory facilities which provide LEO environmental effects. A facility combining vacuum thermal cycling and vacuum ultraviolet (VUV) radiation has been designed and constructed at NASA Lewis Research Center for this purpose. This facility can also be operated without the VUV lamps. An additional facility can be used to provide VUV exposure only. By utilizing these facilities, followed by atomic oxygen exposure in an RF plasma asher, the effects of the individual vacuum thermal cycling and VUV environments can be compared to the effect of the combined vacuum thermal cycling/VUV environment on the atomic oxygen durability of materials. The synergistic effects of simulated LEO environmental conditions on materials were evaluated by first exposing materials to vacuum thermal cycling, VUV, and vacuum thermal cycling/VUV environments followed by exposure to atomic oxygen in an RP plasma asher. Candidate space power materials such as atomic oxygen protected polyimides and solar concentrator mirrors were evaluated using these facilities. Characteristics of the Vacuum Thermal Cycling/VUV Exposure Facility which simulates the temperature sequences and solar ultraviolet radiation exposure that would be experienced by a spacecraft surface in LEO are discussed. Results of durability evaluations of some candidate space power materials to the simulated LEO environmental conditions will also be discussed. Such results have indicated that for some materials, atomic oxygen durability is affected by previous exposure to thermal cycling and/or VUV exposure

Perfect State Transfer in Laplacian Quantum Walk

For a graph $G$ and a related symmetric matrix $M$, the continuous-time quantum walk on $G$ relative to $M$ is defined as the unitary matrix $U(t) = \exp(-itM)$, where $t$ varies over the reals. Perfect state transfer occurs between vertices $u$ and $v$ at time $\tau$ if the $(u,v)$-entry of $U(\tau)$ has unit magnitude. This paper studies quantum walks relative to graph Laplacians. Some main observations include the following closure properties for perfect state transfer: (1) If a $n$-vertex graph has perfect state transfer at time $\tau$ relative to the Laplacian, then so does its complement if $n\tau$ is an integer multiple of $2\pi$. As a corollary, the double cone over any $m$-vertex graph has perfect state transfer relative to the Laplacian if and only if $m \equiv 2 \pmod{4}$. This was previously known for a double cone over a clique (S. Bose, A. Casaccino, S. Mancini, S. Severini, Int. J. Quant. Inf., 7:11, 2009). (2) If a graph $G$ has perfect state transfer at time $\tau$ relative to the normalized Laplacian, then so does the weak product $G \times H$ if for any normalized Laplacian eigenvalues $\lambda$ of $G$ and $\mu$ of $H$, we have $\mu(\lambda-1)\tau$ is an integer multiple of $2\pi$. As a corollary, a weak product of $P_{3}$ with an even clique or an odd cube has perfect state transfer relative to the normalized Laplacian. It was known earlier that a weak product of a circulant with odd integer eigenvalues and an even cube or a Cartesian power of $P_{3}$ has perfect state transfer relative to the adjacency matrix. As for negative results, no path with four vertices or more has antipodal perfect state transfer relative to the normalized Laplacian. This almost matches the state of affairs under the adjacency matrix (C. Godsil, Discrete Math., 312:1, 2011).Comment: 26 pages, 5 figures, 1 tabl

Bronston and Burnside Members: Subdivision of the St. Louis Limestone in South-Central Kentucky

The St. Louis Limestone (Mississippian) of south-central Kentucky consists of two major lithologic units that herein are named, in ascending order, the Bronston Member and Burnside Member. Two other lithologic units occurring in the St. Louis Limestone and in correlative rocks of the Slade Formation (Mississippian), which extends from south-central into northeastern Kentucky, herein are named the Ringgold Bed and Big Sinking Bed. The principal part of the St. Louis Member of the Slade Formation, which consists of Burnside lithologies, herein is renamed the Burnside Member of the Slade. This renaming addresses the problem associated with the previous use of the name St. Louis for both a formation and a member that is only partly correlative with the formation

\u3ci\u3eSchoenophyllum aggregatum\u3c/i\u3e Zone: Stratigraphic Marker for Investigations of Mississippian Limestones in Western Kentucky

Schoenophyllum aggregatum, a Mississippian colonial rugose coral, has a widespread geographic distribution and narrow stratigraphic range in the upper Ste. Genevieve Limestone of western Kentucky. This coral zone serves as a useful stratigraphic marker for commercial and geologic investigations of the extensive limestone deposits formed by the Ste. Genevieve and enclosing limestone units in the region. S. aggregatum is also present in rocks correlative with the Ste, Genevieve that occur in the Monteagle Limestone Slade Formation of south-central Kentucky and the Newman Limestone of southeastern Kentucky

Evaporation of ices near massive stars: models based on laboratory TPD data

Hot cores and their precursors contain an integrated record of the physics of the collapse process in the chemistry of the ices deposited during that collapse. In this paper, we present results from a new model of the chemistry near high mass stars in which the desorption of each species in the ice mixture is described as indicated by new experimental results obtained under conditions similar to those hot cores. Our models show that provided there is a monotonic increase in the temperature of the gas and dust surrounding the protostar, the changes in the chemical evolution of each species due to differential desorption are important. The species H$_2$S, SO, SO$_2$, OCS, H$_2$CS, CS, NS, CH$_3$OH, HCOOCH$_3$, CH$_2$CO, C$_2$H$_5$OH show a strong time dependence that may be a useful signature of time evolution in the warm-up phase as the star moves on to the Main Sequence. This preliminary study demonstrates the consequences of incorporating reliable TPD data into chemical models.Comment: 5 pages, accepted by MNRA

Remember to Include Art and Crafts in your Integrated Curriculum

Discusses ways that arts and crafts can be integrated into content learning activities. Describes activities in a unit on animals in winter, noting that arts and crafts present an opportunity for children to demonstrate learning in new ways. (JW

Generalized Geologic Map for Land-Use Planning: Casey County, Kentucky

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock