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Articles 4741 - 4770 of 5295
Full-Text Articles in Entire DC Network
Evaluation Of Water Quality Data - Beaver Lake - Appendices A - Bt, (Part Iii), James W. Moore
Evaluation Of Water Quality Data - Beaver Lake - Appendices A - Bt, (Part Iii), James W. Moore
Arkansas Water Resources Center Technical Reports
No abstract provided.
Evaluation Of Water Quality Data - Beaver Lake - Section Iv Through Table Xli, (Part Ii), James W. Moore
Evaluation Of Water Quality Data - Beaver Lake - Section Iv Through Table Xli, (Part Ii), James W. Moore
Arkansas Water Resources Center Technical Reports
No abstract provided.
Oklahoma State University And University Of Arkansas, Fayetteville Cooperative Report On Evaluation And Assessment Factors Affecting Water Quality Of The Illinois River In Arkansas, Richard L. Meyer, Art V. Brown, David G. Parker
Oklahoma State University And University Of Arkansas, Fayetteville Cooperative Report On Evaluation And Assessment Factors Affecting Water Quality Of The Illinois River In Arkansas, Richard L. Meyer, Art V. Brown, David G. Parker
Arkansas Water Resources Center Technical Reports
No abstract provided.
Determination Of Optimal Timing Of Poultry Waste Disposal By Meteorological, Hydrological, And Water Quality Modeling Techniques, D. R. Edwards, T. C. Daniel
Determination Of Optimal Timing Of Poultry Waste Disposal By Meteorological, Hydrological, And Water Quality Modeling Techniques, D. R. Edwards, T. C. Daniel
Arkansas Water Resources Center Technical Reports
Approximately one million Mg of broiler litter were generated in conjunction with Arkansas' 1989 broiler production. Common practices for disposal of the waste have the potential to damage the quality of downstream rivers and lakes. This possibility is enhanced due to the concentration of broiler production in areas of the state with shallow soils, steep slopes, and limited suitable disposal area. Since the risk of pollution is greatest immediately following disposal and increases with rainfall depth and intensity, adverse water quality impacts may be mitigated by timing the application to coincide with low probability of surface losses of the nutrients …
The Aquatic Macroinvertebrates Of The White River National Wildlife Refuge, Steve W. Chordas Iii, George L. Harp
The Aquatic Macroinvertebrates Of The White River National Wildlife Refuge, Steve W. Chordas Iii, George L. Harp
Arkansas Water Resources Center Technical Reports
The primary purpose of this study was to survey the diversity of the aquatic macroinvertebrates of the White River National Wildlife Refuge (WRNWR). Determining relative abundance and distributional and seasonal patterns were secondary objectives. No comprehensive investigations of the WRNWR aquatic macroinvertebrates had been conducted previously, and it was hypothesized that this relatively undisturbed area may serve as a refugium. Further, this study provides base line data by which management programs can be composed. Thirty sampling stations were established within the WRNWR. Samples were collected from north to south at a basic rate of five stations per month. Revisit collections …
Water Quality As Affected By Pesticides In Rice Production, W. G. Johnson, T. L. Lavy, J. D. Mattice, B. W. Skulman, R. E. Talbert, R. J. Smith
Water Quality As Affected By Pesticides In Rice Production, W. G. Johnson, T. L. Lavy, J. D. Mattice, B. W. Skulman, R. E. Talbert, R. J. Smith
Arkansas Water Resources Center Technical Reports
Studies were conducted to determine the environmental persistence of the rice pesticides triclopyr, 2,4-D, benomyl and quinclorac. Triclopyr half-lives ranged from <7 d to >100 d depending on depth within the soil profile and clay content. Triclopyr persistence increased as depth within the profile increased and clay content increased. The benomyl metabolite MBC was present at greater than 50% of the initial amount after 9 months in the field. In simulated carryover field studies quinclorac exhibited the greatest potential for injury to subsequent rotational crops. Cotton and soybean growth was reduced when planted at four weeks after quinclorac application. The adsorption of triclopyr …
Determination Of The Abient Toxicity Of The Tailwater Of Nimrod Lake, John T. Knight
Determination Of The Abient Toxicity Of The Tailwater Of Nimrod Lake, John T. Knight
Arkansas Water Resources Center Technical Reports
The objective of this research was to determine if ambient toxicity exists in the receiving stream below a reservoir in which water from the hypolimnion is released. The Ceriodaphnia 7-day test was utilized to determine if toxicity existed. This test is routinely used in the monitoring of municipal and industrial effluent. It has also been utilized in determining if ambient toxicity exists within receiving streams. Nimrod Lake is a flood control impoundment on the Fourche LaFave River in west central Arkansas. The literature suggest that during stratification the hypolimnetic release contains high levels of iron, manganese, ammonia and sulfide during …
The Association Of Water Quality Parameters, Geological Substrates And Periphyton Community Structure, Richard L. Meyer, Julia Christensen Eichman
The Association Of Water Quality Parameters, Geological Substrates And Periphyton Community Structure, Richard L. Meyer, Julia Christensen Eichman
Arkansas Water Resources Center Technical Reports
This research was designed to understand the structure of epilithic diatom assemblage of a first-to-third order stream system which has minimal variance in nutrient concentration, but significant differences in geomorphological character. The primary objective was to determine the importance of geological substrate on the structure of the diatom assemblages. The second objective was to examine the effect of flow on these assemblages, and the third part of the research was to develop a seasonal model of temporal and spatial annual succession. The temporal and spatial models represent the effect of seasons, stream order, substrate characteristics, storm events, and periods of …
Investigation Of The Relationship Of Earthquakes And Underground Waste Disposal In The El Dorado Area, Arkansas, Randel Cox, Roy B. Vanarsdale
Investigation Of The Relationship Of Earthquakes And Underground Waste Disposal In The El Dorado Area, Arkansas, Randel Cox, Roy B. Vanarsdale
Arkansas Water Resources Center Technical Reports
From December, 1983 to September, 1989 twelve small earthquakes were recorded for the El Dorado, Arkansas area. Magnitudes of these earthquakes were well below damaging levels. Prior to this time no seismicity was reported in the area, suggesting that the earthquakes were not naturally occurring and may have been the result of human activity. El Dorado is located at the margin of a region of underground waste brine disposal and along a major fault zone. Elevated pore pressures resulting from brine disposal may have reduced the normal (locking) stresses across fault surfaces and triggered fault movement. Two injection wells (Great …
And For So Long Thereafter - Paying Quantities, Shutting-In, And Other Legal Problems Of The Secondary Term, Thomas A. Daily
And For So Long Thereafter - Paying Quantities, Shutting-In, And Other Legal Problems Of The Secondary Term, Thomas A. Daily
Annual of the Arkansas Natural Resources Law Institute
No abstract provided.
Proceedings Of The Arkansas Academy Of Science - Volume 45 1991, Academy Editors
Proceedings Of The Arkansas Academy Of Science - Volume 45 1991, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
Synopsis Of The Notonectidae Of Arkansas, Stephen W. Chordas Iii, George L. Harp
Synopsis Of The Notonectidae Of Arkansas, Stephen W. Chordas Iii, George L. Harp
Journal of the Arkansas Academy of Science
No abstract provided.
Pleistocene Mammals From The South Sulphur River, Hunt County, Texas, Leo Carson Davis, Kenneth M. Ball
Pleistocene Mammals From The South Sulphur River, Hunt County, Texas, Leo Carson Davis, Kenneth M. Ball
Journal of the Arkansas Academy of Science
Preliminary collecting and excavating along the South Sulphur River has produced a diverse list of fossil mammals. The pampathere, Holmesina septentrionalis, and the large armadillo, Dasypus bellus, with their southern affinities from the extinct megafauna, were found in association with Microtus pennsylvanicus, which has a northern distribution at present. This combination of species argues for climatic conditions and biotic communities during the Pleistocene that have no modern counterparts.
Double Tuned Cosine Coil For Nmr Imaging/Microscopy, Roger M. Hawk, Rao P. Gullapalli, Dikoma P. Shungu
Double Tuned Cosine Coil For Nmr Imaging/Microscopy, Roger M. Hawk, Rao P. Gullapalli, Dikoma P. Shungu
Journal of the Arkansas Academy of Science
The fabrication of a cosine coil having unevenly distributed struts is detailed. Placing the struts in such a manner enables a standing wave at the desired frequency and, hence, only one resonance frequency is obtained. This study details the fabrication of a cosine coil tuned to the LJ-7 frequency (77.76 MHz) and then double-tuned to the H-1 frequency (200.1 MHz) when operated at 4.7 Tesla. Double-tuning is attained by placing an LC trap in series with a capacitor used to single-tune the coil. Also, a method is suggested by which a cosine coil can be broadbanded in the lower frequency …
K-Shell Ionization Measurements For Light Incident Icons, Rahul Mehta, George Bissinger
K-Shell Ionization Measurements For Light Incident Icons, Rahul Mehta, George Bissinger
Journal of the Arkansas Academy of Science
The ionization of the K-shell in targets of copper, silver, dysprosium and gold was investigated with incident ion beams of proton and helium ions in the range 0.5 MeV/u to 3 MeV/u. The x-rays were detected by a HpGe detector. K-shell x-ray production cross section were determined by normalization of the x-ray yield to the incident beam flux, the Rutherford-scattered ions and the nuclear-Coulomb excited gamma ray yield. The multiple normalization procedures minimize the errors in these cross section measurements. The data are compared with the predictions of the ECPSSR theory for K-shell ionization. The atomic number dependence of these …
Observations On The Natural History Of The Mediterranean Gecko, Hemidactylus Turcicus (Sauria: Gekkonidae) In Northwest Arkansas, Mark A. Paulissen, Thomas M. Buchanan
Observations On The Natural History Of The Mediterranean Gecko, Hemidactylus Turcicus (Sauria: Gekkonidae) In Northwest Arkansas, Mark A. Paulissen, Thomas M. Buchanan
Journal of the Arkansas Academy of Science
The Mediterranean gecko, Hemidactylus turcicus, is a small nocturnal lizard introduced into the U.S. A stable population on the campus of Westark Community College in Fort Smith, Sebastian County, Arkansas represents the northernmost U.S. population presently known. We report data on microhabitat usage, feeding behavior, reproduction, and activity patterns. This gecko is active on the outside of buildings during warm months of the year and occasionally inside buildings during the winter. It is most abundant on buildings with many crevices that are used as daytime retreats. It avoids direct illumination of artificial light and usually perches at heights greater than …
75th Annual Meeting, 1991. Program, Academy Editors
75th Annual Meeting, 1991. Program, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
Microwave Pasteurization Of Potting Mixes, Rudolph J. Eichenberger
Microwave Pasteurization Of Potting Mixes, Rudolph J. Eichenberger
Journal of the Arkansas Academy of Science
A study was conducted to determine if potting soils could be pasteurized with a typical 1200 watt microwave oven. Microwave radiation times varied from 0 to 6.0 minutes. Preliminary results indicated that "damping-off" diseases could be prevented in tomato seedlings with the use of potting soils pasteurized by microwaves.
Using Viruses To Examine Soil Treatment Of Septic Tank Effluent, Mark A. Gross, Jenna Hestir, Duane C. Wolf, E. Moye Rutledge
Using Viruses To Examine Soil Treatment Of Septic Tank Effluent, Mark A. Gross, Jenna Hestir, Duane C. Wolf, E. Moye Rutledge
Journal of the Arkansas Academy of Science
Viral contamination of drinking water supplies due to inadequate renovation of septic tank effluent (STE) is a public health concern. The purpose of this paper is to illustrate the use of a bacteriophage to evaluate virus movement in a soil treatment system. Viruses - MS2 bacteriophage - were injected into a wastewater treatment system with soil absorption trenches and drainage tiles, and the drain tile effluent was collected and assayed for the phage. The virus suspension was assayed and a measured amount of STE and virus suspension was pumped into the system allowing for calculation of the influent virus titer. …
Groundwater Hydrology Of A Population Of Lindera Melissifolia In Arkansas, J. Dainette Priest, Robert D. Wright
Groundwater Hydrology Of A Population Of Lindera Melissifolia In Arkansas, J. Dainette Priest, Robert D. Wright
Journal of the Arkansas Academy of Science
Groundwater hydrology was monitored from October through August in and around a bottomland forest pond containing Lindera melissifolia, pondberry. The study site exhibited a series of low ancient dunes and depressions, with seasonal ponds in the depressions. Ponds showed no surface inlets or outlets. Shallow wells were made and soil cores removed along a transect from the top of one dune across the pond to a lower dune. Piezometers were installed in the wells and groundwater levels monitored. Soil core samples were analyzed to determine particle size distribution at soil profile positions selected during field analysis. It was shown that …
Preparation Of A Series Of N-Phenylamides Of 5-Bromo-6-Chloronicontinic Acid And 5-Bromo-2-Chloronicontinic Acid, Frank L. Setliff, Jody Z. Caldwell
Preparation Of A Series Of N-Phenylamides Of 5-Bromo-6-Chloronicontinic Acid And 5-Bromo-2-Chloronicontinic Acid, Frank L. Setliff, Jody Z. Caldwell
Journal of the Arkansas Academy of Science
A series of N-phenylamides of 5-bromo 6-chloronicotinic acid and 5-bromo-2-chloronicotinic acid were synthesized by treatment of their freshly prepared acid chlorides with the appropriately ring substituted anilines. Thirty new compounds were prepared, and their structures were ascertained by elemental analyses and spectroscopic techniques. Spectroscopic trends in the infrared spectra of the two series were examined in an attempt to correlate structural and electronic effects to hydrogen bonding tendencies.
Preparation Of A Series Of Substituted N-Phenyl-5-Bromo-6-Chloro- And 5-Bromo-6-Chloronicotinates Of Potential Agricultural Interest, Frank L. Setliff, Maximillia M. Muguluma, Jody Z. Caldwell
Preparation Of A Series Of Substituted N-Phenyl-5-Bromo-6-Chloro- And 5-Bromo-6-Chloronicotinates Of Potential Agricultural Interest, Frank L. Setliff, Maximillia M. Muguluma, Jody Z. Caldwell
Journal of the Arkansas Academy of Science
Substituted phenyl esters of 5-bromo-2-chloronicotinic acid and 5 bromo 6-chloronicotinic acid were prepared. The acids were first converted to their respective acid chlorides using thionyl chloride, and the acid chlorides were immediately transformed to the esters by treatment with the appropriately substituted phenol in sodium hydroxide solution. Aunique chloride displacement of bromide was observed on attempting to convert 5,6-dibromonicotinic acid to its acid chloride
Homogenous Functions In Thermodynamics, Stephen R. Addison
Homogenous Functions In Thermodynamics, Stephen R. Addison
Journal of the Arkansas Academy of Science
No abstract provided.
Lightning: A Complex Natural Phenomenon That Defies Simple Analysis, Mostafa Hemmati
Lightning: A Complex Natural Phenomenon That Defies Simple Analysis, Mostafa Hemmati
Journal of the Arkansas Academy of Science
No abstract provided.
Nitrate Concentrations Of Ground Water Benton County, Arkansas, Charles R. Smith, Kenneth F. Steele
Nitrate Concentrations Of Ground Water Benton County, Arkansas, Charles R. Smith, Kenneth F. Steele
Arkansas Water Resources Center Technical Reports
No abstract provided.
Nitrate Concentrations Of Ground Water Northern Madison County, Arkansas, Andrew Y. Austin, Kenneth F. Steele
Nitrate Concentrations Of Ground Water Northern Madison County, Arkansas, Andrew Y. Austin, Kenneth F. Steele
Arkansas Water Resources Center Technical Reports
The presence of an extensive network of solution channels in the fractured carbonate bedrock and a thin permeable regolith in northwest Arkansas makes aquifers in this region susceptible to contamination. Because of these conditions, there is concern about nitrate contamination of the ground water from land applied animal wastes, commercial fertilizers, rural septic systems and municipal sewage systems. In response to these concerns a survey was conducted of the nitrate concentration in rural water wells in the carbonate aquifers of a 420 mi2 area of northern Madison county during "wet" and "dry" seasons in 1990. Information from well owners, drilling …
An Evaluation Of The Effect Of Discharging A High Quality Effluent Into A Small Ozark Mountain Stream, David G. Parker, Floyd E. Cotter, Sandra C. Parker
An Evaluation Of The Effect Of Discharging A High Quality Effluent Into A Small Ozark Mountain Stream, David G. Parker, Floyd E. Cotter, Sandra C. Parker
Arkansas Water Resources Center Technical Reports
Recently the newly constructed Fayetteville wastewater treatment plant went on line and directed a portion of its discharge to a point in the Mud Creek drainage basin that had previously not received any effluent. Prior to the discharge, a background study had been performed to establish the water quality in the basin. The background data, when compared to the data collected by this study, allowed any alteration of the stream water quality to be evaluated. Also the modeling procedure used to set the effluent limits for the treatment plant was analyzed. All stream data were compared to the limits set …
Fate Of Nitrogen From The Disposal Of Poultry Litter: A Simulation Approach, B. A. Ibrahim, H D. Scott
Fate Of Nitrogen From The Disposal Of Poultry Litter: A Simulation Approach, B. A. Ibrahim, H D. Scott
Arkansas Water Resources Center Technical Reports
A computer program was written to simulate the transport of nitrogen after an application of poultry litter to a pasture. The program was written in FORTRAN 77 to run on an IBM PC/AT or compatible personal computer or on a Sun SPARCSTATION. Simulation of water, solute and heat transport was by finite difference. Partition of rainfall into infiltration and runoff was by the SCS curve number method. A comparison was made of the computer model output with the results of a field experiment established at the Main Agricultural Experiment Station at Fayetteville. Poultry litter was applied at a rate of …
Virus Reduction By The Stanford Onsite Wastewater Treatment System, Mark A. Gross
Virus Reduction By The Stanford Onsite Wastewater Treatment System, Mark A. Gross
Arkansas Water Resources Center Technical Reports
A field study to examine the Stanford Onsite Wastewater Treatment System's ability to remove bacteriophage from wastewater was conducted. MS2 Coliphage was Injected Into the low pressure pipe (LPP) distribution system to achieve an Influent concentration of 1.6 x 106 plague forming units per milliliter (PFU/ml). The bacteriophage was Injected Into the system three times during the day, and samples were taken from drainage tiles of the treatment system. Tile drainage was assayed on conform bacteria host cultures for MS2 phage. The treatment system removed two to three logs (99% to 99.9%) of the phage. During the past two years, …
A Preliminiary Investigation To Determine The Economic Implications Of The "404" Permit For Constructing Agriculturally Related Reservoirs In Arkansas, Richard K. Ford, Charles R. Britton
A Preliminiary Investigation To Determine The Economic Implications Of The "404" Permit For Constructing Agriculturally Related Reservoirs In Arkansas, Richard K. Ford, Charles R. Britton
Arkansas Water Resources Center Technical Reports
A descriptive inquiry of the economic consequences of federal regulations which restrict the construction of agriculturally related reservoirs in Arkansas's wetlands is presented in this report. The applicable economic principles are identifyed and applied to the situation without the quantifiable information necessary to evaluate the alternatives. The difficulty of collecting the required quantifiable information necessitates the formulation of a different technique to unravel the dilemma. An alternative method for resolving the wetlands allocation question is presented for a public sector decision maker. This unconventional technique suggests that it may be desirable to estimate and compare the costs associated with the …