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Inventory And Characterization Of The Riparian Zone Of The Current And Jacks Fork Rivers, Jonathan Lyon, Cynthia L. Sagers Mar 1998

Inventory And Characterization Of The Riparian Zone Of The Current And Jacks Fork Rivers, Jonathan Lyon, Cynthia L. Sagers

Arkansas Water Resources Center Technical Reports

The ecological, recreational, and economic value of the 134 mile (216 km) riparian corridor within the Ozark National Scenic Riverways (ONSR) is of great interest to land managers and conservationists. Recent interest in applying ecosystem management to forest systems has necessitated a fresh look at the tools and methods in use to assess existing patterns of plant community structure and diversity. The purpose and objective of the study described in this report was to initiate a series of vegetation studies that could be integrated with existing research and management infonnation on the riparian vegetation in the ONSR. Defining the compositional …

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Mud Creek Urban Nonpoint Source Demonstration, Paul Vendrell, K. Teague Jan 1998

Mud Creek Urban Nonpoint Source Demonstration, Paul Vendrell, K. Teague

Arkansas Water Resources Center Technical Reports

Northwest Arkansas is the seventh fastest developing area in the nation. The conversion of rolling pastureland into paved city streets, parking lots, and buildings within this rapidly urbanizing region is reducing infiltration and intensifying stormwater runoff. In the city of Fayetteville alone, the population increased from 42,099 to 58,163 between 1990 and 1999, moving the city across the population threshold which will require the Phase II Stormwater Permit process. Approximately half of Fayetteville is included in the Illinois River Watershed, which has been identified as the third highest priority watershed in need of restoration in the state of Arkansas. Mud …

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Speed Cut-Off Point For Antiforce Waves, Mostafa Hemmati, Mathues Shane Doss, Eric L. George Jan 1998

Speed Cut-Off Point For Antiforce Waves, Mostafa Hemmati, Mathues Shane Doss, Eric L. George

Journal of the Arkansas Academy of Science

A one-dimensional, three-component, fluid model has been employed to investigate the existence of a speed cut-off point for antiforce breakdown waves. The term antiforce wave is used to identify breakdown waves for which the electric field force on electrons is in the opposite direction of wave propagation. The electron fluid-dynamical equations for antiforce waves are different from those of proforce waves. This presentation will address the difference in the set of equations for proforce and antiforce waves and the method of integration of the set of equations through the dynamical transition region for antiforce waves. Also, for antiforce waves, the …

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Applying Binomial Statistics To Weighted Monte Carlo, Sue Ellen Mccloskey, William C. Hall, Wilfred J. Braithwaite Jan 1998

Applying Binomial Statistics To Weighted Monte Carlo, Sue Ellen Mccloskey, William C. Hall, Wilfred J. Braithwaite

Journal of the Arkansas Academy of Science

Weighted Monte Carlo calculations requiring a uniform sampling of the problem-space can suffer from diminished statistical significance because many, if not most, of the randomly-chosen sampling points contribute only slightly to the desired result. Their contribution is reduced in size due the variable-size of the weighting terms. In contrast, none of the randomly-chosen points which are favored by variable size weighting terms will have their statistical significance enhanced beyond that of just one random point in the Monte Carlo sampling. A Monte Carlo analysis was used in earlier work to verify both Gauss' Law and Newton's Shell Theorem. Both examples …

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Publication Policies And Suggestions For Authors, Academy Editors Jan 1998

Publication Policies And Suggestions For Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Quantifying Community Separation And Increase In Number Of Avian Species With Corresponding Increase In Habitat Complexity, An African Example, Douglas A. James Jan 1998

Quantifying Community Separation And Increase In Number Of Avian Species With Corresponding Increase In Habitat Complexity, An African Example, Douglas A. James

Journal of the Arkansas Academy of Science

The relationship between increase in faunal diversity and corresponding increase in habitat complexity was quantified using shrubland bird communities in western Africa. Vegetational characteristics were measured in circular plots around bird positions. Bird species were then arranged from grassy open habitats to dense shrubland and found to be separated into three distinct communities when subjected to Duncan's multiple range procedure in conjunction with discriminant functions analysis. Random samples classified with respect to bird species showed there were few species in the more abundant open habitats and a disproportionate number of species were packed into the less common but complex shrubby …

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Infrared Diode Laser Spectrometer For The Study Of Jet Cooled Gases, Anthony Bednar, Eric Barnett, Candace Lindsay, Trey Heath, Philip Williams, Mark Draganjac, Scott W. Reeve Jan 1998

Infrared Diode Laser Spectrometer For The Study Of Jet Cooled Gases, Anthony Bednar, Eric Barnett, Candace Lindsay, Trey Heath, Philip Williams, Mark Draganjac, Scott W. Reeve

Journal of the Arkansas Academy of Science

We have constructed a tunable, high resolution, infrared diode laser spectrometer and combined it with a pulsed supersonic jet expansion. A modified version of the Perry multipass cell has been incorporated into the spectrometer to increase the effective absorption path length. Performance capabilities of the spectrometer are evaluated by examining ro-vibrational spectra for the carbon monoxide molecule in the five micron region of the infrared. From these measurements, an instrumental absorption sensitivity is determined. Finally, since one of our immediate goals is the infrared study of jet cooled transition metal carbonyls, we present high resolution data obtained by entraining the …

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Continuous Monitoring Of Star's Main Time Projection Chamber, Wilfred J. Braithwaite, Edwin S. Braithwaite Jan 1998

Continuous Monitoring Of Star's Main Time Projection Chamber, Wilfred J. Braithwaite, Edwin S. Braithwaite

Journal of the Arkansas Academy of Science

STAR refers to the Solenoidal Tracking instrument At RHIC (the Relativistic Heavy Ion Collider). For momenta above 500 MeV/c charged kaons are not separated from pions within STAR's Main TPC (Time Projection Chamber) by track density alone and they are poorly separated below 500 MeV/c, even when using information from other sources like the vertex tracker. Within the TPC large numbers of kaons and pions decay into muons (and undetected neutrinos). Earlier work has shown parent pions and kaons whose decays are detected within a TPC may be distinguished uniquely from each other in a two-dimensional plot of muon-emission angle …

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Journal Of The Arkansas Academy Of Science - Volume 52 1998, Academy Editors Jan 1998

Journal Of The Arkansas Academy Of Science - Volume 52 1998, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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82nd Annual Meeting, 1998. Program, Academy Editors Jan 1998

82nd Annual Meeting, 1998. Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Analysis Of A Mixture Of Several Dihalonicotinic Acids By Gas Chromotography And Gas Chromotography-Mass Spectrometry, Cheryl L. Fossler, Frank L. Setliff, Ali U. Shaikh Jan 1998

Analysis Of A Mixture Of Several Dihalonicotinic Acids By Gas Chromotography And Gas Chromotography-Mass Spectrometry, Cheryl L. Fossler, Frank L. Setliff, Ali U. Shaikh

Journal of the Arkansas Academy of Science

Six 2,5- and 5,6- dihalonicotinic acids in a mixture were converted to their corresponding methyl esters and then analyzed by gas chromatography and gas chromatography-mass spectrometry. Four methods of conversion were compared for their GC sensitivity, efficiency and analysis time. In Method #1, using HC1 and methanol as the reagents, the displacement of the halogens by chlorine (from HC1) at 2- and 6-positions was a common occurrence, rendering the method inefficient. In Method #2 (BF3/methanol), the displacement of halogens by methoxide was evident. Method #3 (dicyclohexylcarbodiimide/methanol) produced a mixture of derivatives with a poor yield. Method #4 (diazomethane) gave a …

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Description Of The Sections And Subsections Of The Interior Highlands Of Arkansas And Oklahoma, Thomas L. Foti, George A. Bukenhofer Jan 1998

Description Of The Sections And Subsections Of The Interior Highlands Of Arkansas And Oklahoma, Thomas L. Foti, George A. Bukenhofer

Journal of the Arkansas Academy of Science

Sections and subsections of the Interior Highlands of Arkansas and Oklahoma are redefined, mapped and briefly summarized. The map was produced to support the Ozark- Ouachita Highlands Assessment (OOHA), being conducted by the USDA Forest Service. It revises the USDA Forest Service map "Ecological units of the eastern United States, first approximation" by Keys et al. (1995) and the earlier maps of the natural divisions of Arkansas (Foti, 1974; Foti, 1976; Pell, 1983) to reflect new knowledge and to achieve consistency with units recognized in Missouri. Four sections (natural divisions) are defined as opposed to the three of the previous …

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Effects Of Agricultural Practices On Nutrient Concentrations And Loads In Two Small Watersheds, Northwestern Arkansas, Robin G. Roggio, Kenneth F. Steele, P. F. Vendrell, M. A. Nelson Jan 1998

Effects Of Agricultural Practices On Nutrient Concentrations And Loads In Two Small Watersheds, Northwestern Arkansas, Robin G. Roggio, Kenneth F. Steele, P. F. Vendrell, M. A. Nelson

Journal of the Arkansas Academy of Science

The water quality of two small, adjacent watersheds was monitored to determine the effect of land use on nutrient loads and flow-weighted mean concentrations. Poultry litter and liquid swine waste are surface applied as fertilizer to pastures that are used for hay production and beef cattle grazing. The study area is located in northwestern Arkansas, east central Washington County. Cannon Creek, the less influenced watershed (628 hectares), contains 11% pasture; whereas, Shumate Creek, the more influenced watershed (589 hectares), contains 22% pasture and receives approximately four times more land applied animal waste as fertilizer. The remaining land cover in both …

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Using Labview To Synchronize An Infrared Diode Laser Spectrometer With A Pulsed Supersonic Jet Expansion, Philip Williams, Anthony Bednar, Eric Barnett, Scott W. Reeve Jan 1998

Using Labview To Synchronize An Infrared Diode Laser Spectrometer With A Pulsed Supersonic Jet Expansion, Philip Williams, Anthony Bednar, Eric Barnett, Scott W. Reeve

Journal of the Arkansas Academy of Science

We describe software developed with LabVIEW to provide operational control for an in-house infrared diode laser spectrometer that has been combined with a pulsed supersonic jet expansion sample source. Data were collected with this instrument using a modified version of the rapid-scanning method. A prerequisite in employing the rapid-scan detection scheme is that the modulation used to scan the laser be synchronized in time with the electrical signal used to trigger the pulsed gas valve. Software performance was evaluated by examining a series of rotation vibration (ro-vibrational) spectra for the carbon monoxide molecule in the five micron region of the …

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Preparation Of Methyl 5-Chloro-6-Fluoronicotinate By Fluoride-Chloride Exchange, Frank L. Setliff, Leslie B. Coop Jan 1998

Preparation Of Methyl 5-Chloro-6-Fluoronicotinate By Fluoride-Chloride Exchange, Frank L. Setliff, Leslie B. Coop

Journal of the Arkansas Academy of Science

No abstract provided.

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Continuation Of Illinois River Water Quality Monitoring Of Moores Creek, Paul F. Vendrell Dec 1997

Continuation Of Illinois River Water Quality Monitoring Of Moores Creek, Paul F. Vendrell

Arkansas Water Resources Center Technical Reports

In Northwest Arkansas, nutrients transported by surface water are a major concern. These nutrients are implicated in causing water quality impairment of lakes in Northwest Arkansas and eastern Oklahoma. The nutrients of concern are nitrogen and phosphorus. Nitrogen and phosphorus stimulate algae production in water bodies and can cause objectionable water quality. Problems associated with algae growth are aesthetic impairment, objectionable taste and odor of potable water, interference with recreation activities, and fish kills in some hyper-eutrophic cases. The sources of these nutrients are primarily from land application of confined animal wastes as soil amendments to pastures. In 1990, the …

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Arkansas Soil Fertility Studies 1996, Wayne E. Sabbe Apr 1997

Arkansas Soil Fertility Studies 1996, Wayne E. Sabbe

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

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Beaver Lake Water Quality Enhancement Project Data Analysis, Thomas Soerens, Brian E. Haggard, David G. Parker Mar 1997

Beaver Lake Water Quality Enhancement Project Data Analysis, Thomas Soerens, Brian E. Haggard, David G. Parker

Arkansas Water Resources Center Technical Reports

No abstract provided.

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Spatial Analysis Of The Cause Of Mercury Contamination Of Fish In Arkansas - A Report Submitted To The Arkansas Mercury Task Force, H. S. Lin, H. D. Scott Jan 1997

Spatial Analysis Of The Cause Of Mercury Contamination Of Fish In Arkansas - A Report Submitted To The Arkansas Mercury Task Force, H. S. Lin, H. D. Scott

Arkansas Water Resources Center Technical Reports

There have been concerns about mercury (Hg) contamination in fish in Arkansas since the discovery of the problem in the Ouachita River in 1992 (Armstrong et aI., 1995). Of the more than 170 lakes and streams sampled by the Mercury Task Force from 1992 through 1994, 23% had fish with Hg concentrations exceeding the FDA Action Level of 1 ppm (Armstrong et aI., 1995). Cause of the fish Hg contamination, however, is unknown. Given the economic, human-health and environmental costs associated with fish Hg contamination, it is critical that the cause of this widely-spread problem be identified. Determination of the …

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Publication Policies And Suggestions For Authors, Academy Editors Jan 1997

Publication Policies And Suggestions For Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Investigation Of The Statistical And Spatial Distributions Of Mercury Contaminated Fish, Surface Waters And Soils In Arkansas, H. D. Scott, J. M. Mckimmey Jan 1997

Investigation Of The Statistical And Spatial Distributions Of Mercury Contaminated Fish, Surface Waters And Soils In Arkansas, H. D. Scott, J. M. Mckimmey

Arkansas Water Resources Center Technical Reports

Mercury (Hg) contamination of fish is a widespread problem throughout much of the United States and the world (Louisiana WWW page, 1997). Levels ofHg in fish suffic1ent to exceed the FDA action level of 1 mg kg-1 have been found in many water bodies, including some in Arkansas and Louisiana. As a result of the serious public health ramifications for developing fetuses and for people that subsist on native fish, fish consumption advisories due to Hg contamination have been issued in 29 states. Contamination of surface water bodies by Hg results from deforestation, forest fires, fossil fuels, mining, natural emissions …

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Separating K+/- From Pi+/- Using In-Flight Decays To Mu+/- + Nu, Wilfred J. Braithwaite, Edwin S. Braithwaite Jan 1997

Separating K+/- From Pi+/- Using In-Flight Decays To Mu+/- + Nu, Wilfred J. Braithwaite, Edwin S. Braithwaite

Journal of the Arkansas Academy of Science

A method is presented for completely distinguishing between charged kaons and charged pions by using their charged muon (plus neutrino) decays (with neutrinos undetected) for meson laboratory momenta up to 1000 MeV/c. When either a charged kaon or a charged pion decays into a muon and a neutrino, momentum-energy (four-momentum) conservation will be used to provide unique "kinematic trajectories" for distinguishing kaon decays from pion decays when the change in three-momentum of the muon from that of either parent kaon or pion is measured (or simulated). Ina magnetic field, observation of a tracked particle showing a "kink" and/or a change …

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Ground Flora Composition Following Harvesting Of A Bottomland Hardwood Forest In The Mississippi River Batture Lands, James E. Kellum, Eric Sundell, Brian Roy Lockhart Jan 1997

Ground Flora Composition Following Harvesting Of A Bottomland Hardwood Forest In The Mississippi River Batture Lands, James E. Kellum, Eric Sundell, Brian Roy Lockhart

Journal of the Arkansas Academy of Science

No abstract provided.

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81st Annual Meeting, 1997. Secretary's Report And Financial Statement, Academy Editors Jan 1997

81st Annual Meeting, 1997. Secretary's Report And Financial Statement, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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81st Annual Meeting, 1997. Program, Academy Editors Jan 1997

81st Annual Meeting, 1997. Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Preparation Of Powder Precursors And Evaporation Of Photoconductive Indium Sulfide Films, Chris Barber, Robert Engelken, Brandon Kemp, Wasim Aleem, Imran Khan, Chris Edrington, Michael Buck, Clayton Workman, Anup Thapa, Tom Jakobs Jan 1997

Preparation Of Powder Precursors And Evaporation Of Photoconductive Indium Sulfide Films, Chris Barber, Robert Engelken, Brandon Kemp, Wasim Aleem, Imran Khan, Chris Edrington, Michael Buck, Clayton Workman, Anup Thapa, Tom Jakobs

Journal of the Arkansas Academy of Science

We have demonstrated significant photoconductance in indium sulfide thin films prepared by thermal vacuum evaporation ofIn2$3 powders synthesized in-house by chemical precipitation ofInCl3 or In(CH3COO)3, and (NH4)2S or Na2S. The Delta G lambda/Gdark values have been as high as 0.1 in the initial unoptimized films. Excess sulfur (via a mixture of polysulfide and sulfide ions in the synthesis bath) appears to be important in achieving reproducible and large photoconductivities. In2S3 is particularly attractive as a lower toxicity alternative to CdS in optoelectronic applications such as photovoltaic and photoconductive cells.

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Coplanarity Test For Selecting A Pair Of Charged-Particle Tracks Resulting From A Single Neutral-Particle Decay, Edwin S. Braithwaite, Wilfred J. Braithwaite Jan 1997

Coplanarity Test For Selecting A Pair Of Charged-Particle Tracks Resulting From A Single Neutral-Particle Decay, Edwin S. Braithwaite, Wilfred J. Braithwaite

Journal of the Arkansas Academy of Science

It is hard to determine directly the position of a neutral subatomic particle, but when such a particle decays into a pair of charged particles, it is easy to determine the positions of the charged decay particles and thereby infer the position of the parent particle at the time of its decay. A minimum of two coordinate points for each of the two decay particles is needed to reconstruct the position of the parent vertex. The mathematics of the reconstruction process is inherently interesting, and it can be used to demonstrate to students the utility of some of the most …

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Journal Of The Arkansas Academy Of Science - Volume 51 1997, Academy Editors Jan 1997

Journal Of The Arkansas Academy Of Science - Volume 51 1997, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Electron Shock Waves: Effect Of Current On Electron Temperature And Density, Mostafa Hemmati, Mathues Shane Doss Jan 1997

Electron Shock Waves: Effect Of Current On Electron Temperature And Density, Mostafa Hemmati, Mathues Shane Doss

Journal of the Arkansas Academy of Science

In our attempt to find analytical solutions for breakdown waves, we employ a set of three-component fluid equations. In addition to reporting the method of integration of electron fluid dynamical equations through the dynamical transition region (sheath region), the wave profile for ionization rate, electron number density and electron temperature inside the sheath will be discussed. Also, the effect of the current on electron temperature, electron number density and ionization rate will be reported.

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Acidity Studies Of Deuterated Acids And Bases Commonly Used As Buffers In Nmr Studies, Rose M. Mcconnell, Walter E. Godwin, Brant Stanley, M. Shane Green Jan 1997

Acidity Studies Of Deuterated Acids And Bases Commonly Used As Buffers In Nmr Studies, Rose M. Mcconnell, Walter E. Godwin, Brant Stanley, M. Shane Green

Journal of the Arkansas Academy of Science

Structure based drug development is currently considered to be an important strategy for drug discovery. This strategy requires that critical knowledge of the three dimensional binding site on receptor molecules be known. NMR studies are frequently employed to ascertain important structural data on individual proteins as well as complexes of proteins with ligands. Deuterium labeled acids and bases are frequently used as buffers in deuterium oxide solutions for NMR studies on the structural conformations of bioactive molecules. Since pH is an important factor in any study of the conformational and stereochemical aspects of biologically active molecules, deuterated buffers are an …

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