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Articles 4801 - 4830 of 5295
Full-Text Articles in Entire DC Network
Characterization Of Radioactivity In Hot Springs National Park, Arkansas, C. E. Epperson, N. R. Rhodes
Characterization Of Radioactivity In Hot Springs National Park, Arkansas, C. E. Epperson, N. R. Rhodes
Journal of the Arkansas Academy of Science
No abstract provided.
Status Of The Accelerator Project At Uca, Jack Gaiser, Harold L. Pray
Status Of The Accelerator Project At Uca, Jack Gaiser, Harold L. Pray
Journal of the Arkansas Academy of Science
No abstract provided.
Management Of The Ozark Big-Eared Bat, Plecotus Townsendii Ingens, In Arkansas, Michael J. Harvey, Sam W. Barkley
Management Of The Ozark Big-Eared Bat, Plecotus Townsendii Ingens, In Arkansas, Michael J. Harvey, Sam W. Barkley
Journal of the Arkansas Academy of Science
No abstract provided.
Determining Pesticide And Nitrate Levels In Spring Water In Northwest Arkansas, T. L. Lavy, B. A. Dehart, John D. Mattice
Determining Pesticide And Nitrate Levels In Spring Water In Northwest Arkansas, T. L. Lavy, B. A. Dehart, John D. Mattice
Arkansas Water Resources Center Technical Reports
Occurrences of pesticides in our nations ground water are on the rise. As states become aware of this problem and begin monitoring programs, incidence of contamination will probably increase. Since the problem of pesticides in groundwater is relatively new, little research has centered on the fate of pesticides after they reach the groundwater environment. In Northwest Arkansas efforts to monitor groundwater for pesticides have been small. Twenty-five springs in Northwest Arkansas were sampled in the fall of 1988, and spring of 1989. Analysis for atrazine, alachlor, metolachlor, diuron, and simazine in spring water was preformed using gas liquid chromatography and …
Analysis, Design And Implementation Of A Pilot Relational Database For Groundwater In The State Of Arkansas, Ray Hashemi-Nassab
Analysis, Design And Implementation Of A Pilot Relational Database For Groundwater In The State Of Arkansas, Ray Hashemi-Nassab
Arkansas Water Resources Center Technical Reports
There are several agencies within the state of Arkansas dealing with underground water. Each agency has its own database that acts as an isolated depository of data. Practically, the communication among these databases is zero, not because there is no need for it, but because the communication is very difficult if not impossible. Data redundancy, inconsistency, and lack of integrity is overwhelming. In this study we have addressed the problem of lack of unity among the databases belonging to different agencies. Also, as an alternative we have developed a relational database. In this database the data was normalized to 4NF. …
An Expert System For Managing An Activated Sludge Wastewater Treatment Plant, Sandra C. Parker, David G. Parker
An Expert System For Managing An Activated Sludge Wastewater Treatment Plant, Sandra C. Parker, David G. Parker
Arkansas Water Resources Center Technical Reports
A diagnostic expert system for an activated sludge wastewater treatment plant has been designed to link with a relational database management system for obtaining operational parameter values that are used by the program to diagnose operational problems that may occur in the process. The problems that are dealt with by the system are bulking sludge, floating sludge, defloculation, ashing, solids washout, foaming problems, high soluble effluent BOD and problems in the aeration system. The link between the expert system and the database is accomplished via programming that is initiated by the expert system program. The operator of the system is …
Minimizing The Potential For Groundwater Contamination From Agricultural Point Sources, Joseph H. Massey, Terry L. Lavy, John D. Mattice
Minimizing The Potential For Groundwater Contamination From Agricultural Point Sources, Joseph H. Massey, Terry L. Lavy, John D. Mattice
Arkansas Water Resources Center Technical Reports
An activated charcoal filtration unit was designed to remove pesticides from leftover pesticide solutions and rinsates generated under farm-like conditions. The system, fabricated for less than $1400 using readily available components, effectively removed the pesticides atrazine, benomyl, carbaryl, fluometuron, metolachlor, and trifluralin from wastewater generated on the University of Arkansas Agronomy Farm located in Fayetteville, AR. A total of 2253 L of wastewater were treated using the system. Of these 1768 L were generated from washing out the spray tank (rinsates) while 485 L stemmed from leftover pesticide solutions that were mixed, but not applied. Typical initial pesticide concentrations in …
Improving Irrigation Scheduling And Water Use Efficiency In Cotton, Derrick M. Oosterhuis
Improving Irrigation Scheduling And Water Use Efficiency In Cotton, Derrick M. Oosterhuis
Arkansas Water Resources Center Technical Reports
Cotton (Gossypium hirsutum L) is an important crop in the southern United States. The crop is grown in both irrigated and rainfed situations and is seldom free from periods of water shortages at some stage during the season. In recent years the need for consistency in yields and a stable cash flow has resulted in a rapid expansion in the number of irrigated acres of cotton in the Mississippi Delta. Irrigation research has, however, not kept pace with this expansion. This project represents a start at meeting this urgent need. The influence of weather patterns necessitates that these studies be …
Simulation Of The Fate Of Nitrogen From The Disposal Of Poultry Litter, H. D. Scott
Simulation Of The Fate Of Nitrogen From The Disposal Of Poultry Litter, H. D. Scott
Arkansas Water Resources Center Technical Reports
A PC/AT computer model was developed to simulate the transport of water, nitrate and ammonia in the soil profile after an application of poultry litter to pasture. The model was written using FORTRAN 77 compiler and can be used on any IBM type compatible computer with a math coprocessor. Poultry litter has been shown to be a potential source of plant nutrients, but mismanagement can result in nitrate pollution of the surface and groundwater. The model is composed of a main program, 11 subroutines and three subprograms. An example was shown of the flexibility and dynamic nature of the computer …
Presentation Of Verified Algal Taxa As Reference Sources, Richard L. Meyer
Presentation Of Verified Algal Taxa As Reference Sources, Richard L. Meyer
Arkansas Water Resources Center Technical Reports
A data base of the algae of Arkansas ecoregions has been established to describe the numerous taxa that occur within the aquatic ecosystems included in these regions. The organisms were identified with the aid of diverse literature from throughout the world. These sources are written in multiple languages and the living organisms had to be compared with outline or silhouette drawings. These illustrations may include shading, but none present the true color of the organism but only the characteristics of the descriptive source. Primary characteristics used to identify algae is based upon pigmentation of the plastid and the number and …
Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use, James W. Moore
Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use, James W. Moore
Arkansas Water Resources Center Technical Reports
River water samples from the five sites were collected by the U. S. Geological Survey (USGS) in accordance with their established sampling procedures. Samples for wet chemistry and atomic absorption analyses were delivered to the Bell Engineering Center at the University of Arkansas by USGS personnel. Samples for organics analyses from the Lee Creek, Dardanelle, Little Rock and Pine Bluff sites were delivered by USGS to American Interplex in Little Rock. Samples for organics analyses for the Van Buren site were delivered to the Bell Engineering Center and sent by United Parcel Service (next day air) to Daily Analytical Services …
7li Nmr Of Normal Human Erythrocytes, Rao P. Gullapalli, Roger M. Hawk, Richard A. Komoroski
7li Nmr Of Normal Human Erythrocytes, Rao P. Gullapalli, Roger M. Hawk, Richard A. Komoroski
Journal of the Arkansas Academy of Science
Lithium has been known to be an effective medication for people with bipolar disorder. The mechanisms of action of lithium in the brain is not very well understood. NMR spectroscopy and imaging are effective both in determining lithium levels in tissue and brain. We have monitored lithium levels in red blood cells. We have been able to separate intra- and extracellular compartments of lithium using shift reagents, thereby obtaining T^1 's of both the compartments. Lithium uptake as a function of hematocrit was monitored weekly over a 3 week period. The time constant of 50 mM lithium uptake at 25°C …
Concept Decomposition, Walter A. Sedelow Jr.
Concept Decomposition, Walter A. Sedelow Jr.
Journal of the Arkansas Academy of Science
Historically, perhaps the most general paradigm for scientists has been decomposition —as with, e.g., 'elements' in chemistry, and the basic structures/processes of theoretical physics. Knowledge representation research is encouraging a somewhat comparable activity in computer science, by way of the study of knowledge representation structures and knowledge representation systems. Symbol sets, rules of usage (including divergent inferencing engines) and conceptual primitives are among the entities involved in this process of decomposition.
Preparation Of A Series Of Pyridyl Phenylureas Of Potential Agricultural Interest, Frank L. Setliff, Steve H. Rankin, Mark W. Milstead
Preparation Of A Series Of Pyridyl Phenylureas Of Potential Agricultural Interest, Frank L. Setliff, Steve H. Rankin, Mark W. Milstead
Journal of the Arkansas Academy of Science
Substituted phenylurea derivatives of 3-amino-2-chloro-5-methylpyridine and 5-amino-2-chloro-3- methylpyridine were prepared by treating the amines with appropriately substituted phenyl isocyanates. Structure- confirming spectral data are also presented.
Concert Recording 1989-10-30, Rico Mcneela, Linda Ingle, Debbie Martin, Deanna Hume, Daren Wingard, Stephen Setser, Andrew Wagner, Jennifer Moores, Susan Moore, John Ringley, Carlton Woods, Robert Mueller, Ronda Mains, Theresa Delaplain, Elizabeth Howick, Christine Monson, Chalon L. Ragsdale, James Greeson, James Greeson, James Adams, Robert Mueller
Concert Recording 1989-10-30, Rico Mcneela, Linda Ingle, Debbie Martin, Deanna Hume, Daren Wingard, Stephen Setser, Andrew Wagner, Jennifer Moores, Susan Moore, John Ringley, Carlton Woods, Robert Mueller, Ronda Mains, Theresa Delaplain, Elizabeth Howick, Christine Monson, Chalon L. Ragsdale, James Greeson, James Greeson, James Adams, Robert Mueller
Concert Recordings & Programs
Concerto for 9 instruments, op. 24 / Anton Webern -- Fratres (1980) / Arvo Pärt -- Impromptu / Thea Musgrave -- Three dances for organ / Calvin Hampton -- Luminare / Daniel Lentz -- Madrigals, book IV / George Crumb -- El polifomo de oro / Reginald Smith Brindle -- December 1952 Four Systems / Earle Brown
73rd Annual Meeting, 1989. Program, Academy Editors
73rd Annual Meeting, 1989. Program, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
Bacterial Quality Of Private Water Wells In Clark County, Arkansas, S. Conine, D. Cox, K. Mitchell, Clark Kuyper, Jimmy D. Bragg
Bacterial Quality Of Private Water Wells In Clark County, Arkansas, S. Conine, D. Cox, K. Mitchell, Clark Kuyper, Jimmy D. Bragg
Journal of the Arkansas Academy of Science
Most private water wells in Clark County appeared to be contaminated by bacteria, apparently entering the wells from surface water seepage. Eighteen to 24% of the wells investigated were positive for fecal contamination. Deeper wells were less often contaminated. More than one-half of the wells sampled exceeded recommended limits of inorganic chemicals for safe potable water. High concentrations of iron and manganese were most common, exceeding recommended limits in more than 40% of the wells
Proceedings Of The Arkansas Academy Of Science - Volume 43 1989, Academy Editors
Proceedings Of The Arkansas Academy Of Science - Volume 43 1989, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
Blackland Prairies Of Southwestern Arkansas, Thomas L. Foti
Blackland Prairies Of Southwestern Arkansas, Thomas L. Foti
Journal of the Arkansas Academy of Science
The Blackland Prairie community type has been described in Texas; related communities exist in Alabama and Mississippi. The Arkansas variant of the community has not been described in detail. Since the Arkansas Natural Heritage Commission began a systematic inventory of the community in 1985, more than 36 remnants have been identified that retain substantial natural character. However, all show some degree of disturbance. Based on aerial photo interpretation, aerial inspection, and ground study, an initial description of the community is presented, including original distribution, soil, vegetation and relationship to similar communities of Texas, Mississippi, and Alabama.
Soil Micromorphologic Features Of Holocene Surface Weathering And A Possible Late Quaternary Buried Soil, Northwest Arkansas, Diane Phillips, Margaret J. Guccione
Soil Micromorphologic Features Of Holocene Surface Weathering And A Possible Late Quaternary Buried Soil, Northwest Arkansas, Diane Phillips, Margaret J. Guccione
Journal of the Arkansas Academy of Science
Micromorphologic features of an alfisol developed in White River alluvium near Fayetteville, Arkansas are typical for this soil order. The A horizon has a relatively high organic matter content and an abundance of quartz sand grains with a silt and clay matrix. Voids are relatively common and some have been partly infilled. In contrast to the A horizon, the E horizon has less organic matter, larger voids, and some weak orientation of the clay matrix. The parent material for these horizons was deposited in the past 4,700 years and these pedologic horizons have formed since that time. In the underlying …
Concept Association, Sally Yeates Sedelow
Concept Association, Sally Yeates Sedelow
Journal of the Arkansas Academy of Science
The complement to decomposition in scientific research is composition. In human language computing, composition is achieved by way of semantic association and the generation of strings of entities. That generation of strings takes place progressively: e.g., strings of symbols (words), strings of strings (sentences), strings of strings of strings (paragraphs), etc. The mathematical (topological, graph-theoretic) analysis of Roget's Thesaurus (1962) has opened a door onto a broad vista of potential achievements in such areas as artificial intelligence and expert systems, through the analysis of concept association, or concept composition.
Publication Policies And Suggestions For Authors, Academy Editors
Publication Policies And Suggestions For Authors, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
Books And Letters Vol. 2, No. 2, University Libraries, John A. Harrison, Michael J. Dabrishus, Ethel C. Simpson, Deborah M. Cochran, Deborah E. Kulczak, Kim E. Scott
Books And Letters Vol. 2, No. 2, University Libraries, John A. Harrison, Michael J. Dabrishus, Ethel C. Simpson, Deborah M. Cochran, Deborah E. Kulczak, Kim E. Scott
Books and Letters
Statewide Newspaper Project Underway; Director's Column; Interlibrary Loan Services; Children's Book Exhibit; Personnel Notes; Lemke Exhibit
Virtually Interactive Large-Scale Model For Arkansas: User's Guide (Vilma), Rosalinda R. A. Cantiller, Richard C. Peralta
Virtually Interactive Large-Scale Model For Arkansas: User's Guide (Vilma), Rosalinda R. A. Cantiller, Richard C. Peralta
Arkansas Water Resources Center Technical Reports
This user’s guide supports the use of VILMA (Virtually Interactive Large-scale Model for Arkansas). This document presents the basic concepts in Chapter I. Chapter II discusses the execution steps that the user follows during a VILMA session. Chapter III provides a detailed illustration of example data files. Chapter IV presents two example VILMA sessions. Finally, Chapter V elaborates on additional concepts. The Appendices consist of relevant program listings, instructions, and example files. In this user’s guide, the word "interactive" means the user enters his responses to the prompts that appear on a computer terminal while he is logged on to …
Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter - Ii, D. C. Wolf, J. T. Gilmour, P. M. Gale
Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter - Ii, D. C. Wolf, J. T. Gilmour, P. M. Gale
Arkansas Water Resources Center Technical Reports
In Arkansas, approximately 1 Tg of poultry (Gallus gallus domesticus) manure and litter is produced annually. These waste products are commonly applied to pastures as a soil amendment or fertilizer, but excessive application rates and poor management practices could result in nutrient contamination of ground and surface water. The purpose of this study was to: (1) assess the nutrient concentrations in poultry manure and (2) evaluate the nitrogen loss from land-applied poultry litter and manure due to ammonia volatilization and denitrification. Analyses for total Kjeldahl nitrogen (TKN), inorganic nitrogen (Ni), phosphorus (P), and potassium (K) were compared in 12 wet …
Development Of A Combined Quantity And Quality Model For Optimal Management Of Unsteady Groundwater Flow Fields, R. C. Peralta, J. Solaimanian, C. L. Griffis
Development Of A Combined Quantity And Quality Model For Optimal Management Of Unsteady Groundwater Flow Fields, R. C. Peralta, J. Solaimanian, C. L. Griffis
Arkansas Water Resources Center Technical Reports
Presented are alternative techniques for including conservative solute transport within computer models for optimizing groundwater extraction rates. Unsteady two-dimensional flow and dispersed conservative solute transport are assumed. Comparisons are made of the practicality of including modified forms of implicit and explicit finite difference solute transport equations within optimization models. These equations can be calibrated and subsequently used within a MODCON procedure. The MODCON modelling procedure consists of an integrated series of five optimization or simulation modules. The procedure is applicable for either an entire aquifer system or for a subsystem of a larger system. The first module, A, computes physically …
Qualitative And Quantitative Aquatic Algal Data Compilation To Determine Macrotrends - Iv, Richard L. Meyer
Qualitative And Quantitative Aquatic Algal Data Compilation To Determine Macrotrends - Iv, Richard L. Meyer
Arkansas Water Resources Center Technical Reports
A data base of the algae of Arkansas ecoregions has been estabblished by the use of a relational data base management system (dBase III plus). The system was chosen to be readily available for a variety of microcomputers using MS- and PC-DOS. The data base contains taxonomic fields from division through variety, synonymy, authors, initial description, date, and definitive descriptive source. The data are cross-referenced by ecoregion, Round's community and subcommunity designations. The data base contains greater than 1,500 taxonomic records in all divisions and classes of freshwater algae. The data are sortable by any of the included parameters. The …
Long-Term Reconstruction And Analysis Of White River Streamflow, M. K. Cleaveland, D. W. Stahle, J. G. Hehr
Long-Term Reconstruction And Analysis Of White River Streamflow, M. K. Cleaveland, D. W. Stahle, J. G. Hehr
Arkansas Water Resources Center Technical Reports
A 281-year reconstruction of White River annual runoff at Clarendon, Arkansas, was developed from a regional average of nine Oklahoma, Missouri, and Arkansas tree-ring chronologies (six post oak, Quercus stellata, and three baldcypress, Taxodium distichum). Inhomogeneity of the gaged series was detected with both double mass analysis (using state average total annual Arkansas precipitation) and regression (using the regional tree-ring average). Simple regression calibrated the homogeneous runoff data with the average ring width data from 1930 to 1980. Comparing the reconstruction with independent data verified the regression model. Variance of the reconstruction increases significantly during the 20th century, a change …
Publication Policies And Suggestions For Authors, Academy Editors
Publication Policies And Suggestions For Authors, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
72nd Annual Meeting, 1988. Program, Academy Editors
72nd Annual Meeting, 1988. Program, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.