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Full-Text Articles in Physical Sciences and Mathematics

He Ii Reverberation In Active Galactic Nucleus Spectra, Mark C. Bottorff, Jack A. Baldwin, Gary J. Ferland, Jason W. Ferguson, Kirk T. Korista Dec 2002

He Ii Reverberation In Active Galactic Nucleus Spectra, Mark C. Bottorff, Jack A. Baldwin, Gary J. Ferland, Jason W. Ferguson, Kirk T. Korista

Physics and Astronomy Faculty Publications

This paper compares the observed reverberation response lags and the intensity ratios of the broad-line region (BLR) emission lines He II λ1640, He II λ4686, and C IV λ1549 with predictions. Published observations indicate that the He II λ1640 lag is 3 times shorter than the lags of He II λ4686 or C IV λ1549. Diverse models, however, do not reproduce this observation. Extensive improved numerical simulations of the hydrogenic isoelectronic sequence emission show that the He II spectrum remains especially simple, even in the central regions of a luminous quasar. Line trapping never builds up a significant population of …


2002 Kentucky River Watershed Watch Data Collection Effort, L. Ormsbee, M. Mcalister Oct 2002

2002 Kentucky River Watershed Watch Data Collection Effort, L. Ormsbee, M. Mcalister

Kentucky River Watershed Watch

No abstract provided.


A Mechanical System For Soil Reconstruction, John Patrick Fulton, Larry G. Wells, Timothy D. Smith Sep 2002

A Mechanical System For Soil Reconstruction, John Patrick Fulton, Larry G. Wells, Timothy D. Smith

Biosystems and Agricultural Engineering Faculty Publications

One of the most perplexing problems associated with reclaiming surface–mined lands is excessive compaction of soil due to the heavy earthmoving equipment used during the reclamation process. Over the years, some innovative material handling schemes have been devised to limit vehicle traffic during reclamation on reconstructed soil. However, final grading operations can often create root–limiting bulk densities, which affect plant growth and yield. The purpose of this article is to describe a mechanism designed at the University of Kentucky whereby mine soil can be reconstructed without introducing compaction caused by surface traffic in order for the soil to sustain desirable …


Temperature Variations From Hubble Space Telescope Imagery And Spectroscopy Of Ngc 7009, R. H. Rubin, N. J. Bhatt, R. J. Dufour, B. A. Buckalew, M. J. Barlow, X.-W. Liu, P. J. Storey, B. Balick, Gary J. Ferland, J. P. Harrington, P. G. Martin Aug 2002

Temperature Variations From Hubble Space Telescope Imagery And Spectroscopy Of Ngc 7009, R. H. Rubin, N. J. Bhatt, R. J. Dufour, B. A. Buckalew, M. J. Barlow, X.-W. Liu, P. J. Storey, B. Balick, Gary J. Ferland, J. P. Harrington, P. G. Martin

Physics and Astronomy Faculty Publications

We present new Hubble Space Telescope (HST)/WFPC2 imagery and STIS long-slit spectroscopy of the planetary nebula NGC 7009. The primary goal was to obtain high spatial resolution of the intrinsic line ratio [O III] 4364/5008 and thereby evaluate the electron temperature (Te) and the fractional mean-square Te variation (tA2)across the nebula. The WFPC2 Temap is rather uniform; almost all values are between 9000–11 000 K, with the higher Te values closely coinciding with the inner He++ zone. The results indicate very small values–≲0.01– for …


Pumping Or Mixing System Using A Levitating Magnetic Element, Aexandre N. Terentiev Jul 2002

Pumping Or Mixing System Using A Levitating Magnetic Element, Aexandre N. Terentiev

Physics and Astronomy Faculty Patents

A system capable of pumping or mixing relatively warm fluids using a rotating magnetic element or bearing levitated by a cold superconducting element is disclosed. The magnetic element or bearing carries at least one impeller and is placed in a fluid vessel positioned external to the outer wall of a cryostat or other housing for the superconducting element. A separate cooling source thermally linked to the superconducting element provides the necessary cooling to create the desired superconductive effects and induce levitation in the magnetic element or bearing. The outer wall or housing defines a chamber around the cold superconducting element …


The Physical Conditions Within Dense Cold Clouds In Cooling Flows - Ii, Gary J. Ferland, A. C. Fabian, R. M. Johnstone Jul 2002

The Physical Conditions Within Dense Cold Clouds In Cooling Flows - Ii, Gary J. Ferland, A. C. Fabian, R. M. Johnstone

Physics and Astronomy Faculty Publications

This is a progress report on our numerical simulations of conditions in the cold cores of cooling flow condensations. The physical conditions in any non-equilibrium plasma are the result of a host of microphysical processes, many involving reactions that are research areas in themselves. We review the dominant physical processes in our previously published simulations, to clarify those issues that have caused confusion in the literature. We show that conditions in the core of an X-ray-illuminated cloud are very different from those found in molecular clouds, largely because carbon remains substantially atomic and provides powerful cooling through its far infrared …


Dust Emission From Active Galactic Nuclei, Maia Nenkova, Željko Ivezić, Moshe Elitzur May 2002

Dust Emission From Active Galactic Nuclei, Maia Nenkova, Željko Ivezić, Moshe Elitzur

Physics and Astronomy Faculty Publications

Unified schemes of active galactic nuclei require an obscuring dusty torus around the central source, giving rise to a Seyfert 1 line spectrum for pole-on viewing and Seyfert 2 characteristics in edge-on sources. Although the observed IR is in broad agreement with this scheme, the behavior of the 10 μm silicate feature and the width of the far-IR emission peak remained serious problems in all previous modeling efforts. We show that these problems find a natural explanation if the dust is contained in approximately five to 10 clouds along radial rays through the torus. The spectral energy distributions of …


Method Of Solubilizing Unshortened Carbon Nanotubes In Organic Solutions, Robert C. Haddon, Jian Chen, Mark A. Hamon Apr 2002

Method Of Solubilizing Unshortened Carbon Nanotubes In Organic Solutions, Robert C. Haddon, Jian Chen, Mark A. Hamon

Chemistry Faculty Patents

Naked carbon nanotubes are dissolved in organic solutions by terminating the nanotubes with carboxylic acid groups and attaching an aliphatic carbon chain so as to render the carbon nanotubes soluble.


Dissipative Heating And Quasar Emission Lines, Mark Bottorff, Gary J. Ferland Apr 2002

Dissipative Heating And Quasar Emission Lines, Mark Bottorff, Gary J. Ferland

Physics and Astronomy Faculty Publications

Recent observations reveal that the profiles of emission lines of active galactic nuclei are too smooth to be produced by discrete thermal (T~104 K) clouds. The lines may also be too bright to be powered by the continuum unless a large covering factor or additional heating mechanisms are present. We have been investigating one possible explanation of these observations, namely, that the clouds are turbulent. This paper focuses on observational effects caused by dissipation of turbulent energy into cloud heating. We find that internal heating can explain these observations. Clouds energized by both the ionizing continuum and …


A Portable Rainfall Simulator For Plot–Scale Runoff Studies, J. Byron Humphry, Tommy C. Daniel, Dwayne R. Edwards, Andrew N. Sharpley Mar 2002

A Portable Rainfall Simulator For Plot–Scale Runoff Studies, J. Byron Humphry, Tommy C. Daniel, Dwayne R. Edwards, Andrew N. Sharpley

Biosystems and Agricultural Engineering Faculty Publications

Rainfall simulators have a long history of successful use in both laboratory and field investigations. Many plot–scale simulators, however, have been difficult to operate and transport in the field, especially in remote locations where water or electricity is unavailable. This article describes a new rainfall simulator that is relatively easy to operate and transport to and from the field while maintaining critical intensity, distribution, and energy characteristics of natural rainfall. The simulator frame is constructed from lightweight aluminum pipe with a single 50 WSQ nozzle centered at a height of 3 m (9.8 ft). An operating nozzle pressure of 28 …


Metallicities And Abundance Ratios From Quasar Broad Emission Lines, Fred Hamann, K. T. Korista, Gary J. Ferland, Craig Warner, Jack Baldwin Jan 2002

Metallicities And Abundance Ratios From Quasar Broad Emission Lines, Fred Hamann, K. T. Korista, Gary J. Ferland, Craig Warner, Jack Baldwin

Physics and Astronomy Faculty Publications

The broad emission lines (BELs) of quasars and active galactic nuclei (AGNs) are important diagnostics of the relative abundances and overall metallicity in the gas. Here we present new theoretical predictions for several UV BELs. We focus specifically on the relative nitrogen abundance as a metallicity indicator, based on the expected secondary enrichment of nitrogen at metallicities Z≳0.2 Z. Among the lines we consider, NIII]λ1750/OIII]λ1664, NVλ1240/(CIVλ1549+OVIλ1034), AND NV/HeIIλ1640 are the most robust diagnostics. We argue, in particular, that the average N V BEL is not dominated by scattered Lyα photons from a broad absorption-line wind. We then …


Groundwater Quality In Kentucky: Arsenic, R. Stephen Fisher Jan 2002

Groundwater Quality In Kentucky: Arsenic, R. Stephen Fisher

Information Circular--KGS

Arsenic is a naturally occurring element found in low concentrations in rocks, soils, water, plants, and animals (Nriagu, 1994 a, b). In Kentucky, arsenic is commonly found in iron sulfide minerals associated with coal deposits and black shales. Arsenic is released when iron sulfides oxidize during weathering. Once released, it is readily sorbed onto iron oxides and iron oxyhydroxides, which limits arsenic concentrations in the near-surface environment.


Kentucky Is Karst Country! What You Should Know About Sinkholes And Springs, James C. Currens Jan 2002

Kentucky Is Karst Country! What You Should Know About Sinkholes And Springs, James C. Currens

Information Circular--KGS

Kentucky is one of the most famous karst areas in the world. What is karst? It's a landscape with sinkholes, sinking streams, caves, and springs. Much of Kentucky's beautiful scenery, particularly in the Inner Bluegrass Region, is the result of the development of karst landscape. A large amount of Kentucky's prime farmland (including its famous horse farms) is underlain by karst, and springs and wells in karst areas supply water to thousands of homes. Many of Kentucky's major cities, including Frankfort, Louisville, Lexington, Lawrenceburg, Georgetown, Winchester, Paris, Versailles, Nicholasville, Fort Knox, Bowling Green, Elizabethtown, Munfordville, Russellville, Hopkinsville, …


Groundwater Quality In Kentucky: Ph, R. Stephen Fisher Jan 2002

Groundwater Quality In Kentucky: Ph, R. Stephen Fisher

Information Circular--KGS

The parameter pH (the negative base-10 logarithm of hydrogen ion activity, measured in moles per liter) indicates whether a substance will behave as an acid or base. It is one of the most important parameters that describe groundwater quality, because pH largely controls the amount and chemical form of many organic and inorganic solutes in groundwater.


Water Well And Spring Map Of The Evansville 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2002

Water Well And Spring Map Of The Evansville 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.


Water Well And Spring Map Of The Harrodsburg 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2002

Water Well And Spring Map Of The Harrodsburg 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.


Water Well And Spring Map Of The Louisville 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2002

Water Well And Spring Map Of The Louisville 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.


Water Well And Spring Map Of The Falmouth, Cincinnati, And Madison 30 X 60 Minute Quadrangles, Kentucky, Bart Davidson Jan 2002

Water Well And Spring Map Of The Falmouth, Cincinnati, And Madison 30 X 60 Minute Quadrangles, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.


Bronston And Burnside Members: Subdivision Of The St. Louis Limestone In South-Central Kentucky, Garland R. Dever Jr., Jack R. Moody Jan 2002

Bronston And Burnside Members: Subdivision Of The St. Louis Limestone In South-Central Kentucky, Garland R. Dever Jr., Jack R. Moody

Report of Investigations--KGS

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 …


Mapped Karst Groundwater Basins In The Lexington 30 X 60 Minute Quadrangle, James C. Currens, Randall L. Paylor, Joseph A. Ray Jan 2002

Mapped Karst Groundwater Basins In The Lexington 30 X 60 Minute Quadrangle, James C. Currens, Randall L. Paylor, Joseph A. Ray

Map and Chart--KGS

This map shows karst groundwater basins in the Lexington quadrangle, determined primarily by groundwater tracer studies. It can be used to quickly identify the groundwater basins and springs to which a site may drain. Major springs and the relative size of their catchment areas can be evaluated for potential as water supplies. The map also serves as a geographic index to literature on karst groundwater in the area.


Water Well And Spring Map Of The Somerset 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2002

Water Well And Spring Map Of The Somerset 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.


Kentucky River Basin Management Plan, Kentucky Water Resources Research Institute Jan 2002

Kentucky River Basin Management Plan, Kentucky Water Resources Research Institute

KWRRI Research Reports

This report summarizes how agency activities will be coordinated in the Kentucky River basin during the fiver year cycle beginning in July 2002. It sets out the criteria and processes that guide state and federal programs to take particular actions.


Fiber Optic Sensor Response To High Levels Of Fat In Cream, Czarena L. Crofcheck, Frederick A. Payne, Clair L. Hicks, M. Pinar Mengüç, Sue E. Nokes Jan 2002

Fiber Optic Sensor Response To High Levels Of Fat In Cream, Czarena L. Crofcheck, Frederick A. Payne, Clair L. Hicks, M. Pinar Mengüç, Sue E. Nokes

Biosystems and Agricultural Engineering Faculty Publications

A light backscatter technique using optical fibers to deliver and receive light was investigated for measuring the milkfat content of unhomogenized cream. Light backscatter through cream at wavelengths of 450 to 900 nm was measured for fiber separation distances from 2 to 6.5 mm and for cream containing 10 to ~40 weight percent (wt%) milkfat. Unhomogenized cream (~40 wt% milkfat) was mixed with skim milk (~0.05 wt% milkfat) to yield samples with five different milkfat levels. Three optical response models were tested for correlation with milkfat content: one using the light intensity measurement at a single separation distance, the second …


Inventory Of Karst Springs Of Fayette County, Kentucky, James C. Currens, Qianhong Wu, Kenneth G. Pidgeon Jan 2002

Inventory Of Karst Springs Of Fayette County, Kentucky, James C. Currens, Qianhong Wu, Kenneth G. Pidgeon

Map and Chart--KGS

The purpose of this publication is to document karst springs in Fayette County and provide a resource to help the county's citizens avoid the geologic hazards associated with building near springs during future urban development. It may be used as an aid in locating potential groundwater discharge points in case of hazardous material spills, and to provide a foundation for future studies of the hydrogeology and karst geology of the Inner Bluegrass Region.

It is also a basic historical record of the springs of Fayette County. Although over 350 springs are reported here, this inventory is not exhaustive. At the …


Water Well And Spring Map Of The Beaver Dam 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2002

Water Well And Spring Map Of The Beaver Dam 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.


Generalized Geologic Map For Land-Use Planning: Lexington And Fayette County, Kentucky, Daniel I. Carey, Martin C. Noger, Paul Howell Jan 2002

Generalized Geologic Map For Land-Use Planning: Lexington And Fayette County, Kentucky, Daniel I. Carey, Martin C. Noger, Paul Howell

Map and Chart--KGS

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.


Kentucky Water Resources Research Institute Annual Technical Report Fy 2001, Kentucky Water Resources Research Institute, University Of Kentucky Jan 2002

Kentucky Water Resources Research Institute Annual Technical Report Fy 2001, Kentucky Water Resources Research Institute, University Of Kentucky

KWRRI Annual Technical Reports (USGS’s 104b Grant Program)

The FY 2001 Annual Technical Report for Kentucky consolidates reporting requirements of the Section 104(b) base grant award in a single technical report that includes: 1) a synopsis of each research project supported during the period, 2) a list of related reports, 3) a description of information transfer activities, 4) a summary of student support during the reporting period, and 5) notable achievements and awards during the year.


Carboniferous Stratigraphy In The Vicinity Of The Daniel Boone National Forest, Donald R. Chesnut Jr. Jan 2002

Carboniferous Stratigraphy In The Vicinity Of The Daniel Boone National Forest, Donald R. Chesnut Jr.

Map and Chart--KGS

Middle Carboniferous strata on the western margin of the Eastern Kentucky Coal Field crop out along a north-northeast-trending belt sometimes referred to as the western belt of outcrop of the central Appalachian Basin. This belt also coincides with the Daniel Boone National Forest. These rocks are important because they contain coal, oil, and groundwater, and helped create the ruggedly beautiful canyons, rapids, falls, and arches in the national forest and nearby state parks. This report describes the general stratigraphy of these Carboniferous rocks, and is designed to assist stratigraphers, coal geologists, forest managers, science educators, and geology students.

Two cross …


Water Well And Spring Map Of The Lexington 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2002

Water Well And Spring Map Of The Lexington 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.


Water Well And Spring Map Of The Bowling Green 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2002

Water Well And Spring Map Of The Bowling Green 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.