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Artificial Neural Networks Used To Predict Electrical Properties Of Polymers, Sanjay K. Mitra, Qing Luo, Jerry A. Darsey Jan 1997

Artificial Neural Networks Used To Predict Electrical Properties Of Polymers, Sanjay K. Mitra, Qing Luo, Jerry A. Darsey

Journal of the Arkansas Academy of Science

The ability to predict properties of molecules prior to their synthesis can be of great importance in optimizing their design. Substantial savings in time as well as cost can be achieved if some desired properties can be predicted prior to the synthesis of the molecule. The outer orbitals of a molecule are primarily responsible for many different properties of the molecules. These outer orbital parameters can be utilized by an intelligent computing system like an Artificial Neural Network to extract necessary knowledge about the properties of the molecule. An Artificial Neural Network was trained to extract electrical parameters of several …

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Discovery Of Fossil Cretaceous Bird In Southwest Arkansas, Leo Carson Davis, Kathie Harris Jan 1997

Discovery Of Fossil Cretaceous Bird In Southwest Arkansas, Leo Carson Davis, Kathie Harris

Journal of the Arkansas Academy of Science

No abstract provided.

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New Studies Of Polyfuran And Polymers Of 3-Substituted Furan Rings, Rose M. Mcconnell, Walter E. Godwin, Bradley Phillips Jan 1997

New Studies Of Polyfuran And Polymers Of 3-Substituted Furan Rings, Rose M. Mcconnell, Walter E. Godwin, Bradley Phillips

Journal of the Arkansas Academy of Science

No abstract provided.

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Reductive Dechlorinatin Of A 2-Chloronicotinic Acid Under Finkelstein Conditions, Frank L. Setliff, Leslie B. Coop Jan 1997

Reductive Dechlorinatin Of A 2-Chloronicotinic Acid Under Finkelstein Conditions, Frank L. Setliff, Leslie B. Coop

Journal of the Arkansas Academy of Science

No abstract provided.

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Hydrogeological And Hydrochemical Connection Between The Decatur City Spring And Crystal Lake, Benton County, Arkansas, Demetra O. Salisbury, Ralph K. Davis Jan 1997

Hydrogeological And Hydrochemical Connection Between The Decatur City Spring And Crystal Lake, Benton County, Arkansas, Demetra O. Salisbury, Ralph K. Davis

Journal of the Arkansas Academy of Science

Arkansas is ranked nationally in the production of broilers, laying hens, turkey, swine and beef cattle. These animals produce large volumes of waste, which are spread on pasture land as a method of disposal, as well as a source of fertilizer, resulting in nonpoint source contamination of surface water and ground water. One area of concern includes the Decatur City Spring, which provides municipal water for the city of Decatur. A total of eight sites in the surrounding area were monitored routinely for water quality parameters, including pH, specific conductance, and nitrate-nitrogen. Water temperature and spring and lake stage were …

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Watershed Prioritization, David G. Parker, Rod Williams, Hubert D. Scott Dec 1996

Watershed Prioritization, David G. Parker, Rod Williams, Hubert D. Scott

Arkansas Water Resources Center Technical Reports

The overall objective of this two-year study was to evaluate the water quality in the thirty-seven sub-basin watersheds in the Illinois River in Arkansas and to arrive at a watershed prioritization list to use in targeting non-point source activities. A water quality monitoring program was conducted with sampling in all thirty-seven sub-basins during both storm and base flow events and more intensive sampling in eight representative sub-basins during stOffil events. Each sub-basin was sampled seasonally during low flow (base-flow) conditions and during high flow storm (storm flow) conditions. In addition to the regular sampling, the intensive sub-basins were sampled approximately …

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Directory Of Water Related Courses Offered At Colleges And Universites In Arkansas, Kenneth F. Steele Nov 1996

Directory Of Water Related Courses Offered At Colleges And Universites In Arkansas, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

This publication lists the water and water-related courses at several universities and colleges in Arkansas as reported during the Fall of 1996. It Is anticipated that users of this directory will extend beyond college students, and will include professionals seeking continuing education, and professors desiring to exchange information on courses. This directory is not an "absolute" source of water and water-related courses because all of the higher learning institutions in Arkansas are not listed, and, secondly, because the definition of "water and water-related" varies from institution to institution. None-the-less this directory provides a very valuable and impressive reference on water …

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Diversity Of Arkansas Water Resources Research, Kenneth F. Steele Oct 1996

Diversity Of Arkansas Water Resources Research, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

In order to understand, protect, and manage our water resources effectively knowledge is required from many diverse areas of science, engineering, economics, and sociology. These proceedings of the conference on the Diversity of Arkansas Water Resources Research reflect this need and demonstrate how researchers in the state are responding to water issues and problems in Arkansas. The papers in these proceedings are representative of the research in Arkansas, but are only a sample of the work being conducted by universities and government agencies in Arkansas. We are grateful that Arkansas has the expertise available to provide the information necessary to …

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Arkansas Rice Research Studies 1995, R. J. Norman, B. R. Wells Aug 1996

Arkansas Rice Research Studies 1995, R. J. Norman, B. R. Wells

Arkansas Agricultural Experiment Station Research Series

The research reports in this publication represent one year of results; therefore, these results should not be used as a basis for long-term recommendations. Several research reports in this publication dealing with soil fertility also appear in Arkansas Soil Fertility Studies 1995 , Arkansas Agricultural Experiment Station Research Series 450. This duplication is the result of the overlap in research coverage between the two series and our effort to inform Arkansas rice producers of all the research being conducted with funds from the rice check-off. Use of products and trade names in any of the research reports of this publication …

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Influence Of Rice Production On The Quality Of Water In Tailwater Collection Reservoirs, R. A. Dewell, T. L. Lavy Jun 1996

Influence Of Rice Production On The Quality Of Water In Tailwater Collection Reservoirs, R. A. Dewell, T. L. Lavy

Arkansas Water Resources Center Technical Reports

Since maintaining high water quality standards in the state remains a high priority, monitoring for pesticides in water sources must continue. Determining the type, concentration, and characteristics of any pesticides present in water supplies are essential to the overall assessment of water quality. Five independent locations, implementing contained water management systems and recyclable water, were monitored in 1995 and 1996. Irrigation, runoff, and pond water samples were collected every 10 to 14 days between permanent flood establishment and draining. Water samples were transported to the laboratory and extracted for 16 pesticides using solid phase extraction (SPE) techniques. Quantification and confirmation …

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Effects Of Zebra, Mussel, Dreissena Polymorpha Infestation On Lake Dardanelle Water Quality, Charles J. Gagen, Joseph N. Stoeckel Jun 1996

Effects Of Zebra, Mussel, Dreissena Polymorpha Infestation On Lake Dardanelle Water Quality, Charles J. Gagen, Joseph N. Stoeckel

Arkansas Water Resources Center Technical Reports

Zebra mussels recently invaded southern waterways including the Arkansas River. Large-scale filtration of suspended particulate matter by dense populations could alter reservoir ecosystem function. Furthermore, they attach to hard surfaces, thereby threatening normal operations of artificial structures. We designed this study to provide baseline data prior to establishment of high population levels of zebra mussels in Lake Dardanelle. The characterization of spatial and temporal variability in water quality, zooplankton, phytoplankton, and macrophytes will allow testing of several hypotheses. We sampled zebra mussel veliger and settling juvenile densities and zooplankton densities at four fixed sites and the key water quality variables …

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Bioaccumulation Of Methyl Mercury Through A Food Chain, J. T. Knight Jun 1996

Bioaccumulation Of Methyl Mercury Through A Food Chain, J. T. Knight

Arkansas Water Resources Center Technical Reports

The bioaccumulation of mercury through the food chain has received much attention in Arkansas during the last three years. The discovery of mercury contamination and subsequent fish consumption advisories in southwest Arkansas have increased public awareness of the potential for bioaccumulation of different toxic compounds. It is postulated that the mercury problem in Arkansas is a result of methylation and resulting bioaccumulation of mercury as methyl mercury. This study was designed to derive a Bioaccumulation Factor (BAF) for mercury in a simple food chain under controlled conditions. A BAF is calculated by dividing the concentration found in the organism by …

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Identification Of Optimal Locations For Sampling Ground Water For Pesticides In The Mississippi Delta Region Of Eastern Arkansas, H. S. Lin, H. D. Scott, J. M. Mckimmey May 1996

Identification Of Optimal Locations For Sampling Ground Water For Pesticides In The Mississippi Delta Region Of Eastern Arkansas, H. S. Lin, H. D. Scott, J. M. Mckimmey

Arkansas Water Resources Center Technical Reports

Concerns about the presence of pesticides in the Mississippi River Valley alluvial aquifer in the Arkansas Delta have generated the need to develop a map of ground water vulnerability for this region comprised of approximately 10 million acres. Based on the availability of digital data and the scale of this study. we used a modified Pesticide DRASTIC model in a GRASS GIS environment to identify areas that were physically more sensitive to pesticide contamination than other areas within the Delta. Spatial distribution of pesticide loading was estimated from pesticide application rates in different crops and crop distribution map interpreted from …

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An Introduction To Lake And Reservoir Water Quality Modeling, Kenneth H. Reckhow Mar 1996

An Introduction To Lake And Reservoir Water Quality Modeling, Kenneth H. Reckhow

Arkansas Water Resources Center Technical Reports

No abstract provided.

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Illinois River Water Quality Automatic Sampler Installation, David G. Parker, Rodney Williams, Evan Teague Jan 1996

Illinois River Water Quality Automatic Sampler Installation, David G. Parker, Rodney Williams, Evan Teague

Arkansas Water Resources Center Technical Reports

No abstract provided.

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Completion Report: Arkansas State Pesticides In Ground Water Monitoring Project Phase V: Vulnerable Areas In Jackson, Monroe, Lawrence And Lonoke Counties, T. Nichols, P. Vendrell, K. Steele, H. D. Scott, C. Armstrong Jan 1996

Completion Report: Arkansas State Pesticides In Ground Water Monitoring Project Phase V: Vulnerable Areas In Jackson, Monroe, Lawrence And Lonoke Counties, T. Nichols, P. Vendrell, K. Steele, H. D. Scott, C. Armstrong

Arkansas Water Resources Center Technical Reports

In 1996, sixty-seven water samples were drawn from 65 wells, including 62 new wells and 3 wells sampled previously . One Woodruff County well and two Pulaski County wells were resampled. Thirty-two samples were drawn from 30 wells in Monroe County (well #1 was sampled 3 times during this phase) . Ten wells in Jackson County, 12 wells in Lawrence County and 10 wells in Lonoke were also tested (Figures 1-5) . With the completion of Phase V, the number of wells tested has risen to 231 with a total of 258 samples analyzed . Initially, the wells were tested …

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Landuse And Landcover Classification For Independence, Union, Bradley And Cleveland Counties Of Arkansas, H. Don Scott, Kimberly Hofer Jan 1996

Landuse And Landcover Classification For Independence, Union, Bradley And Cleveland Counties Of Arkansas, H. Don Scott, Kimberly Hofer

Arkansas Water Resources Center Technical Reports

Landuse/landcover (LULC} is a function of natural factors such as soils, climate and water and of anthropogenic factors such as predominant use. In Arkansas, the primary use of the land varies depending on the physiographic region. For example, in the Mississippi Delta region of eastern Arkansas row crop agriculture predominates, whereas in the Gulf Coastal Plains forestry dominates. In both regions LULC is spatially and temporally . variable. Knowledge of LULC can be used in estimating the potential for agricultural production, locations of critical ecological areas, siting of homes, small businesses, industries, roads and landfills as well as source areas …

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Publication Policies And Suggestions For Authors, Academy Editors Jan 1996

Publication Policies And Suggestions For Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Measuring Strangeness Production From Relativisitic Collisions Between Pairs Of Nuclei Using A Vertex Time Projection Chamber, Christine A. Byrd, Wilfred J. Braithwaite Jan 1996

Measuring Strangeness Production From Relativisitic Collisions Between Pairs Of Nuclei Using A Vertex Time Projection Chamber, Christine A. Byrd, Wilfred J. Braithwaite

Journal of the Arkansas Academy of Science

At collider energies of 200A-GeV, tracking of charged particle pairs originating from neutrals is dominated by singlystrange KJ.' decays. Counting the number ofsecondary vertex pairs is a method of measuring the strangeness production. The VTX is a four-layer micro-strip gas time projection chamber being designed for use with the STAR instrument in an experiment using the Relativistic Heavy Ion Collider under construction at Brookhaven National Laboratory. Simulated pixel data generated from CERN's Monte Carlo detector-modeling program Geant were put into tables using the TAS sorting structures available from the STAR Collaboration. The response of VTX was mapped for charged pion …

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Estimating Milky-Way Dark Matter: Its Amount And Distribution, Jeffery E. Clayton, Sue Ellen Mccloskey, Wilfred J. Braithwaite Jan 1996

Estimating Milky-Way Dark Matter: Its Amount And Distribution, Jeffery E. Clayton, Sue Ellen Mccloskey, Wilfred J. Braithwaite

Journal of the Arkansas Academy of Science

No abstract provided.

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Partial Characterization Of Bacteriophages Of Pseudomonas Syringae Pv.Tomato, Scott M. Minor, Russell O. Nordeen, Chad E. Paschall Jan 1996

Partial Characterization Of Bacteriophages Of Pseudomonas Syringae Pv.Tomato, Scott M. Minor, Russell O. Nordeen, Chad E. Paschall

Journal of the Arkansas Academy of Science

No abstract provided.

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80th Annual Meeting, 1996. Program, Academy Editors Jan 1996

80th Annual Meeting, 1996. Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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80th Annual Meeting, 1996. Secretary's Report And Financial Statement, Academy Editors Jan 1996

80th Annual Meeting, 1996. Secretary's Report And Financial Statement, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Curing A Summing Error That Occurs Automatically When Fitting A Function To Binomial Or Poisson Distributed Data, Edwin S. Braithwaite, Wilfred J. Braithwaite Jan 1996

Curing A Summing Error That Occurs Automatically When Fitting A Function To Binomial Or Poisson Distributed Data, Edwin S. Braithwaite, Wilfred J. Braithwaite

Journal of the Arkansas Academy of Science

Without special precautions a sum-rule error occurs automatically when a chi-squared procedure is used to fit a funtion to binomial or Poisson distributed histogram data if the function has at least one linear parameter. Since the square of the variance per channel is equal to the mean population, errors are usually approximated using (G2~=yi>0)}; this choice for approximating the variance gives a per-channel error weighting of 1/yi that automatically results in a sum-rule error. This sum-rule error consistently and systematically underestimates the total sum of the data points by an amount equal to the value of %*, resulting in …

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Proceedings Of The Arkansas Academy Of Science - Volume 50 1996, Academy Editors Jan 1996

Proceedings Of The Arkansas Academy Of Science - Volume 50 1996, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Wave Profile For Proforce Current Bearing Waves, Mostafa Hemmati, Steven Young Jan 1996

Wave Profile For Proforce Current Bearing Waves, Mostafa Hemmati, Steven Young

Journal of the Arkansas Academy of Science

A complete wave profile for proforce style of breakdown waves with a current behind the shock front is discussed. The solution of the electron fluid dynamical equations in the sheath region for proforce current bearing waves conforms with the expected conditins for the values of the dynamical variables at the trailing edge of the wave. The wave profile for electric field and electron velocity, temperature, and number density are presented.

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Reference Sediment Selection In The Lower Mississippi Delta, M. T. Moore, C. D. Milam, Jerry L. Farris Jan 1996

Reference Sediment Selection In The Lower Mississippi Delta, M. T. Moore, C. D. Milam, Jerry L. Farris

Journal of the Arkansas Academy of Science

Floodplain deposition has been a critical part in the evolution of Arkansas' Delta ecoregion, and because ofits high potential for such events, this region is highly enriched and extremely fertile. Historically, water quality in the area has been the subject ofscientific study, and as a result littlehas been published on the effects of underlying sediment with associated benthic communities. Sediment analysis is critical to many of the ongoing aquatic studies because ofits significance as both a habitat for benthic organisms and a sink for contaminants. Seven rivers and one creek within the Delta ecoregion were examined for water chemistry, sediment …

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Electrodeposition Of Copper Indium Sulfide Films From Organic Solutions, Arif Raza, Robert Engelken, Brandon Kemp, Imran Khan, Wasim Aleem, Chris Barber Jan 1996

Electrodeposition Of Copper Indium Sulfide Films From Organic Solutions, Arif Raza, Robert Engelken, Brandon Kemp, Imran Khan, Wasim Aleem, Chris Barber

Journal of the Arkansas Academy of Science

We report on organic solutions ofCuCl 2 ,InClg, and elemental sulfur for electrodepositing CuIn x Sv films. CuInS 2 and CuInSe 2 are promising solar cellmaterials; our work on CuInSg prefaces planned work on plating CuInSe 2 from nonaqueous solvents. Two promising solvent systems are (1) mixed propylcne carbonate and water and (2) mixed ethylene glycol, propionic acid, and water (Engelken et al., 1988). Gray-brown films ofCuInx Sy (nominally GuInS2 ) have been plated from both baths. Major problems include (1) reduction ofCu+2 to Cu and Cu x S by the solvent at high temperatures (T>l()0°C), hence depleting Cu+2,(2) …

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Survival Of Fecal Contamination Indicator Organisms In Soil, K. A. Teague, D. C. Wolf, P. F. Vendrell Sep 1995

Survival Of Fecal Contamination Indicator Organisms In Soil, K. A. Teague, D. C. Wolf, P. F. Vendrell

Arkansas Water Resources Center Technical Reports

Soils amended with human or animal waste may result in pathogen contamination of ground and surface water. Because temperature has been shown to affect pathogen survival, two laboratory studies were conducted to evaluate the impact of extremes in temperature on bacterial and viral pathogen indicator die-off in soil. A Captina silt loam was amended with broiler litter (0.1 g/g dry soil), septic tank effluent, or Escherichia coli (ATCC 13706) culture (both at 0.04 and 0.1 mL/g dry soil in the two respective studies), incubated at 5 and 35°C, and analyzed over time to determine the number of fecal coliform, E. …

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Animal Waste And The Land-Water Interface, H. Don Scott, Kenneth Steele Jul 1995

Animal Waste And The Land-Water Interface, H. Don Scott, Kenneth Steele

Arkansas Water Resources Center Technical Reports

This book presents abstracts of research studies conducted on animal wastes and the interface between application of animal waste to land. The abstracts were divided into sections which tend to organize summaries of research studies conducted on similar topics. These topics range from characteristics of animal waste to the effects of animal wastes on streams, lakes, wetlands, and watersheds, development of best management practices, nutrient management, edge of field losses and alternative uses. The posters will be available for viewing from 10:00 a.m. Monday, July 17, until 12:00 noon on Wednesday, July 19, 1995.

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