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Articles 4681 - 4710 of 5295
Full-Text Articles in Entire DC Network
Completion Report: Pesticide And Nitrate Monitoring Results For Craighead, Mississippi, And Poinsett Counties, Arkansas: Phase Ii, Kenneth F. Steele, William R. Clayton, Terry W. Nichols, Paul F. Vendrell
Completion Report: Pesticide And Nitrate Monitoring Results For Craighead, Mississippi, And Poinsett Counties, Arkansas: Phase Ii, Kenneth F. Steele, William R. Clayton, Terry W. Nichols, Paul F. Vendrell
Arkansas Water Resources Center Technical Reports
Because of the concern for potential contamination of ground water by agricultural chemicals, 38 wells drilled in the Mississippi River Valley alluvial aquifer in Mississippi County and the eastern parts of Craighead and Poinsett Counties, Arkansas were analyzed for pesticides and nitrate. The pesticide, fluometuron, was detected in one sample at a concentration of 0.5 mg/L. Bentazon was detected in three samples at concentrations of 2.5, 0.3, and 0.3 mg/L. The occurrences of the pesticides appear to represent isolated incidents rather than a widespread aquifer contamination. All detections were below health and safety standards. Nitrate is present in several wells …
Effect Of Drying On Cyromazine Loss From Surface-Applied Caged-Layer Manure, T. C. Daniel, D. H. Pote, D. R. Edwards
Effect Of Drying On Cyromazine Loss From Surface-Applied Caged-Layer Manure, T. C. Daniel, D. H. Pote, D. R. Edwards
Arkansas Water Resources Center Technical Reports
In Arkansas, much of the environmental concern related to water quality has focused on the high volume of poultry fecal waste spread on the surf ace of local pastures to fertilize forage grass. Cyromazine (N-cyclopropyl-1,3,5-triazine-2,4,6- triamine), a feed-through larvicide used to control house flies (Musca domestica), is often a component of caged-layer manure. Cyromazine is quite soluble and stable in water, and previous research has shown that it can be readily washed from pasture plots by intense rainfall. Therefore, a study was conducted to evaluate increased drying time as a best management practice technique for reducing cyromazine runoff losses from …
Computer Simulation Model Calibration And Validation For Prediction Of Water Quality Impacts Of Poultry Waste Disposal, D. R. Edwards, T. C. Daniel
Computer Simulation Model Calibration And Validation For Prediction Of Water Quality Impacts Of Poultry Waste Disposal, D. R. Edwards, T. C. Daniel
Arkansas Water Resources Center Technical Reports
Runoff and water quality data collected from two pairs of grazed fields in northwestern Arkansas were analyzed to support efforts to model runoff quality from areas receiving poultry manure and other fertilizer sources. The monitoring period described in this report was September 1, 1991 to April 30, 1993. One of each pair of fields was fertilized with inorganic fertilizer, and the other received either poultry litter or manure. Losses of fertilizer constituents were quite low from an agronomic standpoint, ranging from approximately 2-11 kg N/ha/year and 0.5-4.1 kg P04-P/ha/year. Annual losses of fertilizer constituents were dominated by only a small …
Arkansas Rice Research Studies 1992, B. R. Wells
Arkansas Rice Research Studies 1992, 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 longterm recommendations. Several research reports in this publication dealing with soil fertility also appear in Arkansas Soil Fertility Studies 1992, Arkansas Agricultural Experiment Station Research Series 425. 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.
Focus On Phosphorus: Arkansas Water Resources Center Research Conference, Kenneth F. Steele
Focus On Phosphorus: Arkansas Water Resources Center Research Conference, Kenneth F. Steele
Arkansas Water Resources Center Technical Reports
No abstract provided.
Time Projection Chamber's Efficiency, Obtained Using Cern's Geant Code, Christine A. Byrd, Charles M. Byrd, Wilfred J. Braithwaite
Time Projection Chamber's Efficiency, Obtained Using Cern's Geant Code, Christine A. Byrd, Charles M. Byrd, Wilfred J. Braithwaite
Journal of the Arkansas Academy of Science
Geometrical acceptance and reconstruction of tracks have been carried out for a Time Projection Chamber (TPC) used in Experiment NA35: the 35th experiment in the North Area of the Super Proton Synchrotron (SPS), located at the European Organization for Nuclear Research (CERN). NA35 used the SPS at CERN to produce 6.4 TeV beams of 32S for central collisions with Au nuclei. The TPC modeling effort used a modified version of CERN's Monte Carlo program GEANT, which simulates the response of the NA35 TPC to output from CERN's primary event generators. GEANT was used to simulate three-dimensional pixel data in the …
Effects Of Domestic Wastewater Effluent On The Water Quality And Aquatic Macroinvertebrates In A Sharp County, Arkansas Stream, Linda E. Moss, George L. Harp
Effects Of Domestic Wastewater Effluent On The Water Quality And Aquatic Macroinvertebrates In A Sharp County, Arkansas Stream, Linda E. Moss, George L. Harp
Journal of the Arkansas Academy of Science
The purpose of this study was to determine whether the effluent of the Ash Flat Wastewater Treatment Plant changes the water quality or aquatic macroinvertebrate community structure of North Big Creek. Weekly water samples were analyzed for pH, N, P, COD, TSS and fecal coliform bacteria from 17 June to 19 August 1992. Aquatic macroinvertebrates were collected biweekly using a Turtox Indestructible™ Dip Net, and density indices were calculated. Station 1, above the effluent, was a spring habitat. Fecal coliform, N, P, TSS and COD values were higher at this station, while the aquatic macroinvertebrate community was relatively simple. The …
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.
Ichthyofauna Of A Cypress-Tupelo Swamp, Veryl V. Board, Charlotte Allen, Andrea Reeves
Ichthyofauna Of A Cypress-Tupelo Swamp, Veryl V. Board, Charlotte Allen, Andrea Reeves
Journal of the Arkansas Academy of Science
No abstract provided.
Completion Report: Arkansas State Pesticides In Ground Water Monitoring Project, Terry Nichols, Paul Vendrell, Kenneth Steele
Completion Report: Arkansas State Pesticides In Ground Water Monitoring Project, Terry Nichols, Paul Vendrell, Kenneth Steele
Arkansas Water Resources Center Technical Reports
Executive Summary. The Arkansas State Plant Board (ASPB) has completed a monitoring project in Ashley County, Arkansas. Twenty-nine samples from 23 wells were analyzed for 10 pesticides commonly used in Ashley County. The only detection was Metolachlor, at 0. 71 ug/L, in one well. When the well was subsequently resampled no pesticides were detected. Fifteen of the wells were also tested for nitrate. In one of the wells nitrate was measured at 10.3 mg/L. The other wells were all below 0.05 mg/L. Extensive quality assurance (QA) data collected during the project indicate that 94% of the pesticide data meet all …
Woodruff County Groundwater Vulnerability, H. D. Scott
Woodruff County Groundwater Vulnerability, H. D. Scott
Arkansas Water Resources Center Technical Reports
There is much unknown about the extent of pesticide contamination of groundwater in Arkansas. In recent years, several research studies have been conducted where wells for irrigation and domestic uses have been sampled and analyzed for pesticides (Lavy, 1988; USGS,1993; Nichols, et al., 1993). For state and federal regulatory agencies, evaluation of the potential ground water contamination begins with considering those areas in Arkansas where pesticides are used and where the ground water is vulnerable to contamination. With a relatively large area of crops grown in Arkansas and only limited financial resources available for chemical analyses by state and federal …
Proceedings Of The Arkansas Academy Of Science - Volume 47 1993, Academy Editors
Proceedings Of The Arkansas Academy Of Science - Volume 47 1993, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
Ichthyofauna Of The Village Creek System, Anthony Holt, George L. Harp
Ichthyofauna Of The Village Creek System, Anthony Holt, George L. Harp
Journal of the Arkansas Academy of Science
Village creek is a lowland stream lying in the Mississippi Embayment in Randolph, Lawrence and Jackson counties in northeastern Arkansas. The stream has been channelized in Randolph and Lawrence counties as have most of its tributaries. The Jackson County portion of the stream has not been channelized. Twelve sites were sampled seasonally by seining along Village Creek and its tributaries. In addition to seasonal work, six sites were sampled from one to three times each by several methods. A total of 8000 specimens was collected by all means used (7754 at seasonal sites and 246 at supplemental sites). Forty-two species …
Ultraviolet Spectra Of Acetic Acid, Glycine, And Glyphosate, J. Scott Mcconnell, Rose M. Mcconnell, Lloyd R. Hossner
Ultraviolet Spectra Of Acetic Acid, Glycine, And Glyphosate, J. Scott Mcconnell, Rose M. Mcconnell, Lloyd R. Hossner
Journal of the Arkansas Academy of Science
The influence of pH on the ultraviolet spectra of 0.001, 0.005, and 0.010 M glyphosate, glycine, and acetic acid was investigated. Each dilution of each acid was adjusted to acidic, neutral, and basic pH values. Ultraviolet spectra were recorded from 300 to 200 nm for each acid-dilution-pH combination. The wavelength of maximum absorption (Lambdamax) of glyphosate and glycine was slightly higher in the high pH solutions than in the neutral and low pH solutions. The Lambdamax of acetic acid was apparently unaffected by changes in ph. Molar extinction coefficients (epsilon) at Lambdamax increased with pH for all three acids. Regression …
Three Year Study On A Cypress-Tupelo Swamp In Independence County, Arkansas, Veryl V. Board, Andrea Reeves, Charlotte Allen
Three Year Study On A Cypress-Tupelo Swamp In Independence County, Arkansas, Veryl V. Board, Andrea Reeves, Charlotte Allen
Journal of the Arkansas Academy of Science
No abstract provided.
Suppression Of The Oxidation Of S(Iv) In Rainwater, David M. Chittenden Ii
Suppression Of The Oxidation Of S(Iv) In Rainwater, David M. Chittenden Ii
Journal of the Arkansas Academy of Science
No abstract provided.
Microscale Preparation Of Pyrocatechol: The Use Of Sodium Percarbonate In The Dakin Reaction, T. Evans Yamazaki, Dominic T.C. Yang
Microscale Preparation Of Pyrocatechol: The Use Of Sodium Percarbonate In The Dakin Reaction, T. Evans Yamazaki, Dominic T.C. Yang
Journal of the Arkansas Academy of Science
No abstract provided.
S-H Stretching Frequencies In Ruthenium Mercaptan Complexes And The Crystal And Molecular Structures Of [Cpru(Pph3)2(S-C4h, Haengsoon Park, David Minick, Mark Draganjac, Joey W. Crump, A. W. Cordes, Elizabeth M. Holt
S-H Stretching Frequencies In Ruthenium Mercaptan Complexes And The Crystal And Molecular Structures Of [Cpru(Pph3)2(S-C4h, Haengsoon Park, David Minick, Mark Draganjac, Joey W. Crump, A. W. Cordes, Elizabeth M. Holt
Journal of the Arkansas Academy of Science
No abstract provided.
77th Annual Meeting, 1993. Program, Academy Editors
77th Annual Meeting, 1993. Program, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
Computer Model For Predicting Aids Among Intravenous Drug Users, Daniel Berleant, R. Ron Goforth, Jun Yuan
Computer Model For Predicting Aids Among Intravenous Drug Users, Daniel Berleant, R. Ron Goforth, Jun Yuan
Journal of the Arkansas Academy of Science
Intravenous drug abuse (IVDA) is an important cause of HIV transmission. Computer simulation is one way to understand and predict the spread of HIV infection among IVDAs. We design and simulate HIV infection among IVDAs and the impact of AIDS on this community, and thereby predict future IVDA population, HIV levels, AIDS levels, and AIDS deaths in this group. The HIV to AIDS, and AIDS to Death latencies are described by probability density functions (PDFs) in this model. Factors such as the recruit, quit, and normal death rate of IVDAs, are considered, as well as the infection and removal rates …
Botanical Survey Of A Cypress-Tupelo Swamp, Veryl V. Board, Charlotte Allen, Andrea Reeves
Botanical Survey Of A Cypress-Tupelo Swamp, Veryl V. Board, Charlotte Allen, Andrea Reeves
Journal of the Arkansas Academy of Science
Collection of plants from a cypress-tupelo swamp located at the eastern border of Independence County was part of a long range plan to document the flora of the county. Efforts were made to determine if the study area would fit the current federal definition of wetlands which requires aperiodic or permanent inundation of the soil.
Monte Carlo Director Modeling And Display, Using The Cern Laboratory, Christine A. Byrd, Charles M. Byrd, Wilfred J. Braithwaite
Monte Carlo Director Modeling And Display, Using The Cern Laboratory, Christine A. Byrd, Charles M. Byrd, Wilfred J. Braithwaite
Journal of the Arkansas Academy of Science
Detectors for high energy nuclear physics experiments are being modeled using programs developed and maintained at CERN, the European Organization for Nuclear Research. These programs include data handling and display routines, as well as those using random-sampling Monte Carlo techniques to calculate energy depositions for high energy particles as they pass through the various parts of the detector system. The complete CERN library has been imported for use with our Workstation computers in a multiple user environment. The enormous CERN Monte Carlo program GEANT(French for GIANT) tracks the progress of a particle through a detector on a simulated event-by-event basis. …
Larval Chironomids Of The St. Francis Sunken Lands In Northeast Arkansas, Betty G. Cochran, Edmond J. Bacon Jr., George L. Harp
Larval Chironomids Of The St. Francis Sunken Lands In Northeast Arkansas, Betty G. Cochran, Edmond J. Bacon Jr., George L. Harp
Journal of the Arkansas Academy of Science
Sixty semi-annual collections (August 1987-July 1988) were made from 30 stations by sampling each station twice for 1.5 man-hours with an aquatic dipnet. Larval chironomids were mounted on slides and identified at 400-1000 magnifications using a Leitz Dialux 20 EB microscope. A survey of the aquatic macroinvertebrates of the St. Francis Sunken Lands in northeast Arkansas revealed 36 taxa of Order Diptera, Family Chironomidae. The taxa were used to evaluate the general health of the aquatic environment. Stations that were located within the least disturbed areas, which were old river channels and oxbows, contained the highest number of organisms and …
Fishes Of Bayou Meto And Wattensaw Bayou, Two Lowland Streams In East Central Arkansas, Walter Dean Heckathorn Jr.
Fishes Of Bayou Meto And Wattensaw Bayou, Two Lowland Streams In East Central Arkansas, Walter Dean Heckathorn Jr.
Journal of the Arkansas Academy of Science
Bayou Meto is a low-gradient, highly turbid, warm-water stream that originates in the foothills of the Interior Highlands of central Arkansas and flows southeastward 290 km to the Arkansas River. In the 1970's, Bayou Meto was contaminated with dioxins from a point source (Vertac Corp.) now recognized as a USEPA Superfund site. The present study was initiated to investigate the impact of dioxin on the fish community of Bayou Meto. Fishes were collected by backpack-electrofishing, boat-electrofishing, seines, hoopnets, minnow traps, and trot lines, at 14 sampling stations. Diversity indices (Shannon and Margalef) were used to compare diversity among sample sites. …
Environmental Analysis Of The Caddo River And Its Tributaries: Comparison Of Water Quality During 1992 With 1974-75, Kelly L. House, Jimmy D. Bragg, Clark Kuyper, T. Kent Thomas, C. Renn Tumlison
Environmental Analysis Of The Caddo River And Its Tributaries: Comparison Of Water Quality During 1992 With 1974-75, Kelly L. House, Jimmy D. Bragg, Clark Kuyper, T. Kent Thomas, C. Renn Tumlison
Journal of the Arkansas Academy of Science
Environmental data related to water quality of the Caddo River and its tributaries were collected from March - October, 1992, and compared with data from August, 1974 - May, 1975. Bacterial, chemical and physical parameters were investigated at six river locations and thirteen tributary sites. Ammonia, nitrates, soluble phosphorus, turbidity and fecal coliform were significantly lower, and sodium and potassium were significantly higher in 1992 than during the previous study. Bacterial loading exceeded EPA criteria at some locations during both studies.
User-Interface Coding For The Cern/Geant Nuclear Physics Program, David L. Roetzel, Wilfred J. Braithwaite
User-Interface Coding For The Cern/Geant Nuclear Physics Program, David L. Roetzel, Wilfred J. Braithwaite
Journal of the Arkansas Academy of Science
Explanations will be given of the various user-written routines required by the Monte Carlo detector-modeling program GEANT, developed by CERN, the European Organization for Nuclear Research. User-written routines must be linked with the CERN library to accomplish the researcher's intentions. Examples will illustrate how GEANT passes information to subprograms needed to model events. Various data structures used by GEANT library calls and included in each user routine, are similarly illustrated. Both computational-speed and memory-size limitations need to be factored into the construction of a simulation model. This will constrain the calls used in the user-written routines. Examples are provided of …
Determination Of Hammett Pyridine 3-Aza And 4-Aza Replacement Constants By 1h Nmr Studies Of Amide Systems, Frank L. Setliff, Nikhil G. Soman, Alan D. Toland
Determination Of Hammett Pyridine 3-Aza And 4-Aza Replacement Constants By 1h Nmr Studies Of Amide Systems, Frank L. Setliff, Nikhil G. Soman, Alan D. Toland
Journal of the Arkansas Academy of Science
Values for Hammett pyridine 3-aza and 4-aza replacement constants were obtained by correlation of the amide proton chemical shifts (in DMSO) of some N-(3-pyridyl)-and N-(4-pyridyl)-dichloronicotinamides, benzamides and acetamides with those of their N-(substituted phenyl) amide analogs using standard Hammett a values
Sinkhole Excavations In Peccary Cave, Newton County, Arkansas, Kenneth M. Ball, Leo Carson Davis
Sinkhole Excavations In Peccary Cave, Newton County, Arkansas, Kenneth M. Ball, Leo Carson Davis
Journal of the Arkansas Academy of Science
No abstract provided.
Rapid Reduction Of Nitrate Ion In Rain Water, David M. Chittenden Ii
Rapid Reduction Of Nitrate Ion In Rain Water, David M. Chittenden Ii
Journal of the Arkansas Academy of Science
No abstract provided.
Arkansas Agricultural Chemical Ground-Water Management Plan, Gerald King, Darryl Little, Tim Jessup, Charles Armstrong
Arkansas Agricultural Chemical Ground-Water Management Plan, Gerald King, Darryl Little, Tim Jessup, Charles Armstrong
Arkansas Water Resources Center Technical Reports
The Arkansas Agricultural Chemical Ground-Water Management Plan (SMP) is based on the Draft State Pesticide Ground- Water Management Plan Guidance and The Pesticides and Ground-Water Protection Strategy prepared by the U.S. Environmental Protection Agency (EPA). The need for a plan to protect ground water from contamination by agricultural chemicals and agents arises from evidence nationwide that using these chemicals can, in some instances, lead to contamination. In February 1988, EPA proposed a strategy to regulate certain pesticides by prohibiting their use in areas vulnerable to leaching unless a state develops and implements an acceptable management plan. The advantage of a …