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Articles 5101 - 5130 of 5293
Full-Text Articles in Entire DC Network
The Hazen Mammoth (Mammuthus Columbi), Prairie County, Arkansas, William L. Puckette, James A. Scholtz
The Hazen Mammoth (Mammuthus Columbi), Prairie County, Arkansas, William L. Puckette, James A. Scholtz
Journal of the Arkansas Academy of Science
In May 1965, mammoth remains were exposed during the excavation of a borrow pit for construction of Interstate Highway 40, 2 mi northeast of Hazen, Prairie County, Arkansas. The proboscidian remains consisted of a skull with tusks, mandibles, atlas and other skeletal elements. The vertebra material was scattered over approximately 150 m (1,600 sq ft) but was confined to a layer of red clayey-silt 6.7 m (22 ft) below the surface. No additional fauna or flora was recovered. The mammoth remains are referred to Mammuthus columbi (Falconer, 1857) on the basis of characteristics of the dentition, particularly the comparison of …
Twenty Years Of Experience With The University Of Arkansas Planetarium, Paul C. Sharrah
Twenty Years Of Experience With The University Of Arkansas Planetarium, Paul C. Sharrah
Journal of the Arkansas Academy of Science
The Model A-1 Spitz planetarium was placed in operation at the University of Arkansas in 1954. It was moved to its present location in 1972 and has continued to have a much expanded use. More than 8,000 persons attended demonstrations between 1 August 1972 and 31 March 1974. Approximately one third of these were University students in classes and laboratories; the remaining two thirds were accounted for by school and other youth groups and the public demonstrations.
Chemistry Departments In Predominantly Black Institutions, James O. Wear, Nirmal K. Shastri
Chemistry Departments In Predominantly Black Institutions, James O. Wear, Nirmal K. Shastri
Journal of the Arkansas Academy of Science
Chemistry programs in 87 predominantly Black institutions were compared by questionnaire survey. Advanced undergraduate courses were offered for chemistry majors by 86% of these schools, but only 28% offered research and independent study for undergraduates. Although there were extremes, most of the faculty taught 15 to 18 contact hours and their median salaries were below the national median. Library support seemed adequate with 1 to 1.5% of the total library materials being chemistry books, texts and reference, and the libraries of most schools had holdings of 15 principal chemistry-related journals. More than 90% of the schools were well-equipped with laboratory …
Sand Boils: A Modern Analogue Of Ancient Sand Volcanoes, John Glynn Williams
Sand Boils: A Modern Analogue Of Ancient Sand Volcanoes, John Glynn Williams
Journal of the Arkansas Academy of Science
Sand boils are springs that form on the lowland side of an artificial levee containing a river at extremely high flood stage. Hydrostatic pressure generated by the column of river water between the levees causes failure in the sediment of the channel wall and allows water to be forced laterally beneath the levee and out onto the adjacent flood plain. Sand is transported by the moving water and is ejected onto the flood plain at points where the sediment is structurally weak to produce the boils. The sand deposit forms a characteristic sedimentary structure similar to sand volcanos of the …
Preliminary Reconnaissance Water Quality Survey Of The Buffalo National River, R. E. Babcock, H. C. Macdonald, E. E. Dale Jr., R. L. Meyer, Joe Nix, D. G. Parker, Eugene Schmitz
Preliminary Reconnaissance Water Quality Survey Of The Buffalo National River, R. E. Babcock, H. C. Macdonald, E. E. Dale Jr., R. L. Meyer, Joe Nix, D. G. Parker, Eugene Schmitz
Arkansas Water Resources Center Technical Reports
In accordance with Contract No. CX 700030105, dated 12 February 1973, the University of Arkansas , Water Resources Resear ch Center is submitting a "Preliminary Reconnaissance Water Quality Survey of the Buffalo National River." The Water Resources Research Center of Arkansas has supplied the necessary personnel and facil ities to perform a preliminary reconnaissance survey of the Buffalo National River of Arkansas with special emphasis placed on the establishment of both permanent and temporary benchmarks for water quality sampling. Preliminary water quality samples have been collected to make those chemical, physical, and biological analyses as defined by Mr . Roland …
The Economic Impact Of Beaver Lake Reservoir: A Cost Benefit Study, Don R. Market
The Economic Impact Of Beaver Lake Reservoir: A Cost Benefit Study, Don R. Market
Arkansas Water Resources Center Technical Reports
This study was undertaken to determine the impact of Beaver Lake Reservoir on four contiguous Arkansas counties. Analysis of economic data indicated that lake related personal income in the area has, since the project was completed, been about 2.5 percent higher than it would have been had the lake not been constructed. The greatest impact has been associated with the counties having the largest share of the shore line. In the aggregate, however, the most significant cause of economic growth in the area has been associated with growth of manufacturing employment. Also the relative economic position of each of the …
A Eutrophication Model Of The White River Basin Above Beaver Reservoir In Northwest Arkansas, Robert A. Gearhart, Dee Mitchell, Louis Thibodeaux, Richard Meyers
A Eutrophication Model Of The White River Basin Above Beaver Reservoir In Northwest Arkansas, Robert A. Gearhart, Dee Mitchell, Louis Thibodeaux, Richard Meyers
Arkansas Water Resources Center Technical Reports
With national interest focused on man’s ever increasing degradation of the waters in this nation, it is clearly evident that an accurate assessment of all parameters influencing water quality needs to be made. Moreover, nutrient levels and budgets reflecting eutrophication trends are important parameters in the overall factors effecting water quality in lakes and reservoirs. The ability to predict future eutrophication levels will greatly enhance the retardation of the eutrophication process. Through mathematical simulation of this process, eutrophication can be analyzed and intelligent decisions regarding water quality management can be made.
Broad Spectrum Microwave Systems For Remotely Measuring Soil Moisture Content, W. P. Waite, K. R. Cook, B. B. Bryan
Broad Spectrum Microwave Systems For Remotely Measuring Soil Moisture Content, W. P. Waite, K. R. Cook, B. B. Bryan
Arkansas Water Resources Center Technical Reports
A theoretical and experimental study of the microwave reflectivity of soils with varying moisture content was conducted. A system was developed to measure reflectivity over a continuous frequency range of 4 to 26.5 GHz, at incidence angles from 10° to 70°, and with both horizontal and vertical polarization. The measurements were found to be extremely accurate for smooth homogeneous surfaces, however, the effects of surface roughness were found to be more severe than predicted due to the discontinuous nature of naturally occurring rough surfaces. An algorithm was developed which used the frequency dependence of the reflectivity to estimate the effective …
Mathematical Modeling Of Stream Storage Potential, Hugh M. Jeffus
Mathematical Modeling Of Stream Storage Potential, Hugh M. Jeffus
Arkansas Water Resources Center Technical Reports
Streamflow data from unregulated streams in Arkansas were processed through Moran’s Model for a dam. The process involved calculating a cumulative gamma distribution for each stream as the streamflow values were incremented in units of 0.1 cubic feet per second per square mile of drainage area. This gamma distribution was then used as input for Moran’s Model. The output from Moran's Model includes the probability of the reservoir having zero contents as the size of the reservoir is decreased. The logarithm of the probability of zero contents, 1n PO, versus reservoir size, K, is a straight line of the form …
A Study To Improve Dissolved Oxygen Analysis Techniques To Facilitate Water Quality Field Survey Applications, R. W. Raible, M. K. Testerman
A Study To Improve Dissolved Oxygen Analysis Techniques To Facilitate Water Quality Field Survey Applications, R. W. Raible, M. K. Testerman
Arkansas Water Resources Center Technical Reports
This report describes studies made of the temperature characteristics of dissolved oxygen electrodes having a large surface area. Large area electrodes proved to have much longer lifetime between rejuvenations. Many measurements of dissolved oxygen in water need to be made in field situations where recalibration techniques would be difficult and where making temperature corrections is time consuming for operators who may be making numerous measurements. This study was directed toward design of a compensation circuit for a dissolved oxygen electrode which will give the best possible measurement over a large water temperature range of 5° - 35°C without the necessity …
Proceedings Of The Arkansas Academy Of Science - Volume 27 1973, Academy Editors
Proceedings Of The Arkansas Academy Of Science - Volume 27 1973, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
Guidelines For Authors, Academy Editors
Guidelines For Authors, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
57th Annual Meeting, 1973. Secretary's Report And Financial Statement, Academy Editors
57th Annual Meeting, 1973. Secretary's Report And Financial Statement, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
57th Annual Meeting, 1973. Program, Academy Editors
57th Annual Meeting, 1973. Program, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
Logical Transition From Magnetic Poles To Current Loops, H. E. Mccloud
Logical Transition From Magnetic Poles To Current Loops, H. E. Mccloud
Journal of the Arkansas Academy of Science
Consideration of the relationship between the magnetic field produced by a magnetic shell and that produced by a current loop requires the evaluation of the line integral ɸH̅ • dl̅, where a portion of the path must cross the dipole layer. The correct line integral to be evaluated must be ɸB̅ • dl̅. The evaluation of this integral leads immediately to the correct Maxwell equation in ∆ x H̅. Gaussian units are used.
Groundwater - Surface Water Integration Study In The Grand Prairie Of Arkansas, Carl L. Griffis
Groundwater - Surface Water Integration Study In The Grand Prairie Of Arkansas, Carl L. Griffis
Arkansas Water Resources Center Technical Reports
A mathematical model of the Quaternary Aquifer of the Grand Prairie, Arkansas was developed and used to evaluate a variety of methods of artificially recharging this aquifer. In addition, the model was used to evaluate the impact of various levels of water management and the probable movement of artificially recharged water in the aquifer. Improved water management and the use of recharge wells were the two alternatives that showed the most promise as potential solutions. The rate of movement of recharged water was determined by the model to be 300 ft./year under a gradient of 16 ft./mile.
A Survey Of The Fishes Of The Mulberry River, Arkansas, Larry L. Olmsted, Gary D. Hickman, Donald G. Cloutman
A Survey Of The Fishes Of The Mulberry River, Arkansas, Larry L. Olmsted, Gary D. Hickman, Donald G. Cloutman
Arkansas Water Resources Center Technical Reports
Announcement of plans to dam Mulberry River, Arkansas, by the United States Army Corps of Engineers has generated some dispute. Most agruments against damming the stream revolve around environmental degradation and loss of aesthetic values. This report serves as a pre-impoundment survey of the fishes of the Mulberry River so that possible effects of impoundment can be more objectively assessed. Knowledge on the fishes of the Mulberry River is severely lacking. The first study was by Jordan and Gilbert (1886) who collected in the southern U.S. in July, August, and September, 1884. They collected in many streams in Arkansas including …
56th Annual Meeting, 1972. Program, Academy Editors
56th Annual Meeting, 1972. Program, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
56th Annual Meeting, 1972. Secretary's Report And Financial Statement, Academy Editors
56th Annual Meeting, 1972. Secretary's Report And Financial Statement, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
Limnology Of Four Bauxite Open-Pit Lakes, George L. Harp, Ronald D. Hubbard
Limnology Of Four Bauxite Open-Pit Lakes, George L. Harp, Ronald D. Hubbard
Journal of the Arkansas Academy of Science
The aquatic flora and fauna and 18 physicochemical characteristics of four bauxite open-pit lakes were studied from September 1969 to August 1970. The least acid lake (pH 3.4-4.4) supported 49 different aquatic insects, plankton, and higher aquatic plants. The most acid lake (pH 2.7-3.2) supported only 26 different plants and animals. Bauxite open-pit lakes within the pH range studied appear to be as relatively unproductive as their coal strip-mine lake counterparts, with which they share physicochemical and biological characteristics. Benthic macrofaunal diversity and abundance appear to be related more closely to distribution and abundance of leaf detritus than to hydrogen-ion …
Geoelectrical Possibilities Of Detecting Stream Channels In Carbonate Rocks, Reinhard K. Frohlich
Geoelectrical Possibilities Of Detecting Stream Channels In Carbonate Rocks, Reinhard K. Frohlich
Journal of the Arkansas Academy of Science
Several geoelectrical resistivity methods that may be used to determine the position and flow characteristics of underground water associated with carbonate bedrock and karst development are considered. The most promising method studied employs depth soundings patterned after Schlumberger. The plotting of half electrode separation against apparent resistivity yields a curve which may be used to discriminate between lateral and vertical inhomogeneities in bedrock. A network of depth soundings of this type ultimately may lead to a map that will show geoelectrical anisotropies that may be used to analyze subsurface water courses in carbonate rock.
Proceedings Of The Arkansas Academy Of Science - Volume 26 1972, Academy Editors
Proceedings Of The Arkansas Academy Of Science - Volume 26 1972, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
Taxonomic Note On Fossil Glyptostrobus In Northeastern Arkansas, Eugene B. Whittlake
Taxonomic Note On Fossil Glyptostrobus In Northeastern Arkansas, Eugene B. Whittlake
Journal of the Arkansas Academy of Science
Two papers by Brown (1936, 1962) are reviewed and discussed in relation to the validity of specific names applied to the fossil Glyptostrobus as found in North American deposits. Evidence is presented supporting the contention that G. nordenskioldi Brown n. comb, is the valid name for Glyptostrobus specimens from the Hooker site of northeastern Arkansas.
Fracture Pattern Analysis Employing Remote Sensing Techniques For Groundwater Movement With Environmental Applications: Preliminary Report, Bradford C. Hanson
Fracture Pattern Analysis Employing Remote Sensing Techniques For Groundwater Movement With Environmental Applications: Preliminary Report, Bradford C. Hanson
Journal of the Arkansas Academy of Science
The study will consist of determining the relationship between fracture patterns and porosity-permeability changes in carbonate rocks with emphasis on groundwater movement. These porosity-permeability changes will be measured by relative groundwater movement, in the form of either springs, artesian wells, municipal supplies, or private wells. Relationships will be determined by plotting the positions of the measuring sites and correlating these sites with mapped fractures. Water yield is expected to be markedly greater for sites along fracture traces than for those located at random.
Stratigraphy And Sedimentary Structures Of A Middle Bloyd Fluvial Sandstone, Washington And Madison Counties, Arkansas, John M. Glenn
Stratigraphy And Sedimentary Structures Of A Middle Bloyd Fluvial Sandstone, Washington And Madison Counties, Arkansas, John M. Glenn
Journal of the Arkansas Academy of Science
A prominent quartz-pebble-bearing sandstone unit crops out at stream level along the East Fork of the White River in Madison County. Detailed geologic mapping indicates that the unit is stratigraphically positioned between the Brentwood and Dye Shale Members of the Bloyd Formation and is not the Greenland Member of the Winslow Fromation as previously supposed. Sedimentary textures and structures of the unit indicate that it was deposited by competent, unidirectional currents flowing in a southerly direction. These currents were related to a broad braided stream system.
Conversion Of Six Chemical Water Tests From Manual To Automated Methods, Tom N. Palko
Conversion Of Six Chemical Water Tests From Manual To Automated Methods, Tom N. Palko
Journal of the Arkansas Academy of Science
No abstract provided.
A Study Of Phytoplankton Dynamics In Lake Fayetteville As A Means Of Assessing Water Quality, Richard L. Meyer
A Study Of Phytoplankton Dynamics In Lake Fayetteville As A Means Of Assessing Water Quality, Richard L. Meyer
Arkansas Water Resources Center Technical Reports
Phytoplankton community was analyzed for seasonal and vertical distribution in Lake Fayetteville. This northwest Arkansas reservoir maintains a stable water level and chemical input with a relatively constant, slow overflow. Its source is groundwater seepage through a calcareous substrate with little contribution from the limited drainage basin. Phytoplankton community development with its associations and assemblages, chlorophylls -a, -b and c, and biomass distribution are described. The seasonal cycles of the chemical parameters NH4-N, NO2-N, NO3-N, ortho-phosphate, silicon, pH, HCO3- and total-alkalinity plus oxygen are described and discussed. The physical parameters of temperature, light and climate are included. The interaction of …
Interim Report On Water Quality Investigation Degray Reservoir, Arkansas, J. Nix
Interim Report On Water Quality Investigation Degray Reservoir, Arkansas, J. Nix
Arkansas Water Resources Center Technical Reports
Impoundment of the Caddo River near Arkadelphia, Arkansas began in August, 1969. Detailed patterns of the dissolved oxygen distribution in this reservoir are presented for the period September, 1969 through April, 1971. Although the reservoir had not reached normal pool elevation, thermal stratification accompanied by severe hypolimnic oxygen depletion has been observed. The dissolved oxygen data show that an under flow occurs in the fall of the year and carries dissolved oxygen into the hypolimnic zone. The gradients of dissolved oxygen concentration observed during the winter indicate that the reservoir does not undergo complete mixing. A short summary of the …
Environmental Changes Produced By Cold-Water Outlets From Three Arkansas Reservoirs, Carl E. Hoffman, Raj V. Kilambi
Environmental Changes Produced By Cold-Water Outlets From Three Arkansas Reservoirs, Carl E. Hoffman, Raj V. Kilambi
Arkansas Water Resources Center Technical Reports
Water qualities of two natural streams (Buffalo and Kings Rivers), one new coId-tailwater (Beaver), and two old coId-tailwaters (Norfork and Bull Shoals) in northwestern Arkansas were studied from July 1965 through October 1968. The essential difference between the old cold-tailwaters and natural streams is a change in water quality which allows the development of a new productive ecological environment. Features which typify the old tailwaters are as follows: (1) relatively homioithermal temperatures; (2) stream beds scoured by strong hydoelectric power generation currents; (3) abundant phytoplankton and benthic macroinvertebrates; and (4) absence of warm water game fishes. Environmental factors characterizing natural …
Impoundment Effects On Water Quality As Reflected In Parasitism Of Reservoir Basses, David A. Becker
Impoundment Effects On Water Quality As Reflected In Parasitism Of Reservoir Basses, David A. Becker
Arkansas Water Resources Center Technical Reports
Our aquatic environments are rapidly becoming useless as natural resources through pollution from various sources. It is therefore necessary for us to further understand the various means which relate to this process. The interrelationships between the physico-chemical and biological water qualities undergo marked changes during the ageing of a reservoir. Eutrophication of these impoundments render them rela-tively useless as natural resources. It thus becomes apparent that we must gain further knowledge of these processes if we are to devise methods for proper reservoir management.