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Articles 2761 - 2790 of 3135

Full-Text Articles in Physical Sciences and Mathematics

Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use: Volume 4 Cost Analyses, Joseph Watt, James W. Moore May 1990

Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use: Volume 4 Cost Analyses, Joseph Watt, James W. Moore

Arkansas Water Resources Center Technical Reports

Volume IV of the overall report for the project to determine the suitability of the Arkansas River for municipal, agricultural and industrial water supplies contains the cost information calculated using WATER MAID. WATER MAID is an interactive software program for use in calculating treatment plant costs. The software program was developed for the Environmental Protection Agency. The research project was conducted under contract with the Arkansas Soil and Water Conservation Commission.

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Nitrate Concentrations Of Ground Water From Limestone And Dolomitic Aquifers In The Northeastern Washington County Area, Arkansas, Kenneth F. Steele, William K. Mccalister Mar 1990

Nitrate Concentrations Of Ground Water From Limestone And Dolomitic Aquifers In The Northeastern Washington County Area, Arkansas, Kenneth F. Steele, William K. Mccalister

Arkansas Water Resources Center Technical Reports

The Ozark Region of Arkansas is a major poultry-producing area of the United States. Large quantities of poultry waste are spread as fertilizer on thin soils of pastureland overlying limestone and dolomitic aquifers. Because these aquifers provide domestic water supplies for the rural population and are susceptible to contamination from surface water, there is concern that nitrate leached from poultry litter is polluting the ground water. In response to this concern, well water from a major poultry-producing area was compared with that from a forested area in the northeastern Washington County area, Arkansas. Although nitrate concentration of the well water …

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Beaver Lake Water Quality Monitoring Plan, Kenneth W. Carter, George Losak, Kenneth Steele, Joel Cahoon, Dwayne Edwards, Tommy C. Daniel, Richard Meyer, Dee Mitchell Feb 1990

Beaver Lake Water Quality Monitoring Plan, Kenneth W. Carter, George Losak, Kenneth Steele, Joel Cahoon, Dwayne Edwards, Tommy C. Daniel, Richard Meyer, Dee Mitchell

Arkansas Water Resources Center Technical Reports

The Beaver Lake basin is located in Northwest Arkansas, and includes portions of Washington, Madison, Benton, Carroll and Franklin counties. The White River is the :major tributary to Beaver lake, with minor tributaries including the Middle and West Forks of the Whi 1:e River, Richland Creek and War Eagle Creek. The basin encompassing 1,186 square miles of drainage area provides a usable storage capacity of 1.22 :million acre-feet, 300,000 of which are designated as flood control, the remainder is utilized for power generation and water supply. Beaver Lake is the water source for both the Beaver and Carroll County Water …

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On-Line Process Fiber Optic Refractometer For Measuring Edible Oil Hydrogenation, Charles F. Cole, Robert A. Sims, Alois (Al) J. Adams Jan 1990

On-Line Process Fiber Optic Refractometer For Measuring Edible Oil Hydrogenation, Charles F. Cole, Robert A. Sims, Alois (Al) J. Adams

Journal of the Arkansas Academy of Science

The process of edible oil partial hydrogenation has improved steadily over the past decades, but few on-line process instruments exist capable of measuring the extent of hydrogenation. This work describes the design of a prototype, on-line fiber optic refractometer for controlling and monitoring of oils. It uses an established correlation between the degree of hydrogenation of an edible oil and its refractive index (Rl). The refractometer cell uses a bare optical fiber in direct contact with processing oil. Equations are given describing the power transmission characteristics of an optical fiber as a function of its cladding Rl. Comparisons between calculated …

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Arkansas Water Resources Research Center Pamphlet, Kenneth F. Steele Jan 1990

Arkansas Water Resources Research Center Pamphlet, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

Arkansas Water Resources Center (AWRC) works closely with state and federal agencies and academic institutions. Priority research categories are: surface water analysis, ground water pollution, surface and ground water quality/quanity, and water resource management.

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Efficiency In Collecting Fossils, Kenneth M. Ball, Leo Carson Davis Jan 1990

Efficiency In Collecting Fossils, Kenneth M. Ball, Leo Carson Davis

Journal of the Arkansas Academy of Science

Two hundred seventy-two kilograms of sediments and fossils were collected from 1 meter square plots on lake beach and river gravel bars to compare the efficiency of surface collecting with that of intensive laboratory processing. Collecting fossils by visual inspection of the outcrop required an average of 14 minutes 56 seconds per square meter and resulted in 319 vertebrate and 1320 invertebrate fossils. The ratio of time spent collecting and processing sediments to time spent in surface collecting fossils was 4.66:1. The ratio of invertebrates produced by the intensive laboratory process to invertebrates produced by surface collecting was 4.80:1. Vertebrate …

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Rotational Symmetries Of Nuclear States: Spin Determinations In Advanced Laboratory, Wilfred J. Braithwaite Jan 1990

Rotational Symmetries Of Nuclear States: Spin Determinations In Advanced Laboratory, Wilfred J. Braithwaite

Journal of the Arkansas Academy of Science

An advanced laboratory experiment is described which shows the connection between the rotational symmetries of nuclear states and the assignments of spins to discrete nuclear states. Standard angular correlation methods were used to study the two sequential gamma ray transitions in each ⁶⁰Ni nucleus, populated by unobserved beta decays from a weak radioactive ⁶⁰Co source. The chosen electronics and detectors were inexpensive and easy to operate. This experiment was extended to introduce students to real-world data acquisition, using finite-geometry detectors, which resulted in enormously larger coincident data rates.

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Study Of Deposition Methods For Silicon Powder, Kamesh V. Gadepally, Kevin B. Tennal, Roger M. Hawk, Al Robles, James A. Gribel Jan 1990

Study Of Deposition Methods For Silicon Powder, Kamesh V. Gadepally, Kevin B. Tennal, Roger M. Hawk, Al Robles, James A. Gribel

Journal of the Arkansas Academy of Science

Silicon powder tends to agglomerate at normal atmospheric conditions and is, hence, difficult to aerosolize. Several methods of aerosolizing silicon powder and finally depositing it on various substrates were investigated. This paper presents the investigated methods of aerosolization. The electrostatic spray coating used in dry paint application was found to be the most suitable. The general merits of this method and its use for silicon powder deposition to form films are discussed.

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Comparison Of Pressurized And Gravity Distribution Systems For Wastewater Treatment, Mark A. Gross, Stan Neal, Belinda Ederington, Robert Muldoon Jan 1990

Comparison Of Pressurized And Gravity Distribution Systems For Wastewater Treatment, Mark A. Gross, Stan Neal, Belinda Ederington, Robert Muldoon

Journal of the Arkansas Academy of Science

Pressurized distribution of domestic wastewater over a sand filter surface achieves better treatment than gravity distribution. The pressurized distribution system caused the filter to better remove organics (BOD₅) and suspended solids. Pressurized distribution also caused the sand filter to achieve more complete nitrification than the filter having gravity distribution. Two slow sand filters 15.2 cm wide, 3.1 m long and 15.2 cm deep were built and loaded with domestic septic tank effluent for 250 days at a rate of 5.1 cm per day. Influent and effluent samples were collected and analyzed for five-day Biochemical Oxygen Demand (BOD₅), suspended solids, ammonia- …

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Data Acquisition And Control Program For Chromatographic And Spectroscopic Studies, M. Keith Hudson, William G. Hood, Robert Henson Jan 1990

Data Acquisition And Control Program For Chromatographic And Spectroscopic Studies, M. Keith Hudson, William G. Hood, Robert Henson

Journal of the Arkansas Academy of Science

An IBMPC compatible computer was interfaced to an Ithaco 3962 lock-in-amplifier. The computer controlled the functions of the lock-in-amplifier, acquired and stored data, and allowed for real time or off-line processing of data. Computer/amplifier connection was made via RS-232-C serial interface. Programmed in Microsoft Quick BASIC, the computer assumed the role of a dedicated chromatographic integrator. This reduced the overall instrumentation expense by eliminating a dedicated chromatographic integrator. The computer program supplied much greater flexibility in control and data interpretation. To show its utility, the program was applied to a study of the infrared emission from a flame upon the …

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Photoacoustic Detection Of Carbonaceous Atmospheric Aerosols, Duane Jackson Jan 1990

Photoacoustic Detection Of Carbonaceous Atmospheric Aerosols, Duane Jackson

Journal of the Arkansas Academy of Science

The role of carbonaceous aerosols in the atmosphere as a risk factor in climatic changes and health effects and state-of-the-art monitoring processes are briefly presented here. In particular, development of a photoacoustic technique for measuring the concentration of carbonaceous particles is discussed. The photoacoustic measurement is based upon detection of pressure waves generated by localized time-dependent heating of air inside the photoacoustic chamber. Heating of air inside the chamber is due to absorption of visible laser radiation by carbon particles present inside the chamber. The laser radiation is chopped, and the resultant pressure signal produced by subsequent heating and cooling …

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Comparison Of The Molecular Structures Of Monovalent Cation Salets Of N,N-Dimethyldithiocarbamate. Novel Synthesis And Crystal Structure Of (Phi4)(S2cn(Ch3)2)2h2o, Mark Draganjac, David Minick, Elizabeth M. Holt Jan 1990

Comparison Of The Molecular Structures Of Monovalent Cation Salets Of N,N-Dimethyldithiocarbamate. Novel Synthesis And Crystal Structure Of (Phi4)(S2cn(Ch3)2)2h2o, Mark Draganjac, David Minick, Elizabeth M. Holt

Journal of the Arkansas Academy of Science

Crystals of the tetraphenylphosphonium N,N-dimethyldithiocarbamate dihydrate (C₂₇H₃₀NO₂PS₂; F.W. = 495.6) are monoclinic; P2₁/n; a = 13.349(6), b = 20,968(6), c = 9.800(4) Å, β = 109.01(3)°; Z = 4; V = 2593.4(16) Å^3; Dₓ = 1.269 gcm- 3 . Data were collected at ambient temperature using MoKα radiation (λ = 0.71069 Å).F(000) = 1048, linear absorption coefficient, n = 2.80 cm- 1. The structure was solved by direct methods and subsequently refined by full matrix least squares techniques. Final R value = 0.064 for 1 61 0 reflections and 298 varied parameters. Due to the nature of the cation, interactions …

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University Based Multidisciplinary Organizations - Promises And Challenges, Robert L. Cook, Richard D. Benton, Robert A. Green Jan 1990

University Based Multidisciplinary Organizations - Promises And Challenges, Robert L. Cook, Richard D. Benton, Robert A. Green

Journal of the Arkansas Academy of Science

The Diagnostic Instrumentation and Analysis Laboratory (DIAL) at Mississippi State University is a multidisciplinary research organization engaged in developing and applying advanced computer-controlled, optical and laser-based diagnostic instrumentation systems for the characterization of high temperature gas streams. Part of the mission of DIAL is the on-site application of the diagnostic systems to large-scale facilities. The laboratory has approximately 40 professional and support personnel. Twelve faculty members are associated with the laboratory and, because of the multidisciplinary nature of the research program, their disciplines cross college as well as departmental boundaries. This provides for unique graduate research opportunities. Moreover, the laboratory …

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Principles And Clinical Applications Of Magnetic Resonance, Rao P. Gullapalli, Teresa T. Evans, Roger M. Hawk Jan 1990

Principles And Clinical Applications Of Magnetic Resonance, Rao P. Gullapalli, Teresa T. Evans, Roger M. Hawk

Journal of the Arkansas Academy of Science

A review is presented which covers the basic theory of nuclear magnetic resonance (NMR) with regard to angular momentum, magnetic moments, and the classical mechanical description of the NMR experiment. Longitudinal (T,) and Transverse (T2) relaxation times are defined as well as the basic pulse sequences used for their measurement. In particular, the 180°-t-90° and the Hahn Spin Echo pulse sequences are described in detail. Basic Magnetic Resonance Imaging (MRI) theory is discussed with regard to slice selection, frequency encoding, and phase encoding to define the imaged volume element. The equations defining the amount of Tt , T2 , and …

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Educational Software Development Using Hypertext And Expert System Software Concepts, Siripong Malasri, Roger R. Easson Jan 1990

Educational Software Development Using Hypertext And Expert System Software Concepts, Siripong Malasri, Roger R. Easson

Journal of the Arkansas Academy of Science

This paper presents two computer software concepts: hypertext and expert systems; which are useful for educational software development. Good educational software enhances the learning process and offers opportunities for faculty to provide additional materials for independent studies, which would otherwise be impossible, due to the limited time and incredible growing rate of technological progress. The hypertext concept offers the students a non-linear learning style, while the expert system concept provides explanation facilities for students to probe the logic of the systems. Both approaches are extremely useful for educational software. With the proper tools, the courseware can be implemented easily and …

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Soil And Lithostratigraphy Below The Loveland/Sicily Island Silt, Crowley's Ridge, Arkansas, Donna Porter, Sam Bishop Jan 1990

Soil And Lithostratigraphy Below The Loveland/Sicily Island Silt, Crowley's Ridge, Arkansas, Donna Porter, Sam Bishop

Journal of the Arkansas Academy of Science

Two stratigraphic units between the Loveland/Sicily Island Silt and the Pliocene sand and gravel on Crowley's Ridge were analyzed to determine their origin and assess the degree of pedogenic development. The Crowley's Ridge Loess, the upper unit, was up to 2.6 m thick, was not laterally continuous, and contained a well developed paleosol. The lower unit was a several meter thick sandy facies of the Pliocene sand and gravel which contained a weak paleosol. Particle size analysis revealed that the upper unit exhibited texture similar to the overlying loess units, with unimodal silt comprising greater than 95% of the clay-free …

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Design Of A Viscometer Using Magnetostriction Of Ferromagnetic Probes, Subhendra Nath Sarkar Jan 1990

Design Of A Viscometer Using Magnetostriction Of Ferromagnetic Probes, Subhendra Nath Sarkar

Journal of the Arkansas Academy of Science

On-line measurement of viscosity of process liquids at process temperature is difficult though industrially very important. A viscometer is designed which can do this up to about 300 °C almost on-line within about 1-8% accuracy except for very viscous liquids like glucose. It uses a ferromagnetic probe designed to mechanically vibrate in the ultrasonic frequency range. An excitation coil sends repeated excitation current pulses to induce mechanical vibration in the probe tip. When placed in a process fluid, the vibration amplitude is damped due to the viscosity of the fluid, and the damped vibration is sensed by Faraday's principle by …

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Impact Of Microprocessor Protected Mode Programming On Undergraduate Education N Engineering Technology, Robert L. Douglas Jan 1990

Impact Of Microprocessor Protected Mode Programming On Undergraduate Education N Engineering Technology, Robert L. Douglas

Journal of the Arkansas Academy of Science

No abstract provided.

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Characterization Of Radioactivity In Hot Springs National Park, Arkansas, C. E. Epperson, N. R. Rhodes Jan 1990

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.

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Status Of The Accelerator Project At Uca, Jack Gaiser, Harold L. Pray Jan 1990

Status Of The Accelerator Project At Uca, Jack Gaiser, Harold L. Pray

Journal of the Arkansas Academy of Science

No abstract provided.

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Management Of The Ozark Big-Eared Bat, Plecotus Townsendii Ingens, In Arkansas, Michael J. Harvey, Sam W. Barkley Jan 1990

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.

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Determining Pesticide And Nitrate Levels In Spring Water In Northwest Arkansas, T. L. Lavy, B. A. Dehart, John D. Mattice Jun 1989

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 …

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Analysis, Design And Implementation Of A Pilot Relational Database For Groundwater In The State Of Arkansas, Ray Hashemi-Nassab Jun 1989

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. …

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An Expert System For Managing An Activated Sludge Wastewater Treatment Plant, Sandra C. Parker, David G. Parker Jun 1989

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 …

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Minimizing The Potential For Groundwater Contamination From Agricultural Point Sources, Joseph H. Massey, Terry L. Lavy, John D. Mattice Jun 1989

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 …

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Improving Irrigation Scheduling And Water Use Efficiency In Cotton, Derrick M. Oosterhuis Jun 1989

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 …

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Simulation Of The Fate Of Nitrogen From The Disposal Of Poultry Litter, H. D. Scott Jun 1989

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 …

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Presentation Of Verified Algal Taxa As Reference Sources, Richard L. Meyer Jun 1989

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 …

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Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use, James W. Moore Jan 1989

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 …

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7li Nmr Of Normal Human Erythrocytes, Rao P. Gullapalli, Roger M. Hawk, Richard A. Komoroski Jan 1989

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 …

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