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Articles 5071 - 5100 of 5293
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Trace Element Composition Of Stream Sediments An Integrating Factor For Water Quality, Kenneth F. Steele, Harold C. Macdonald, George H. Wagner, William S. Bowen
Trace Element Composition Of Stream Sediments An Integrating Factor For Water Quality, Kenneth F. Steele, Harold C. Macdonald, George H. Wagner, William S. Bowen
Arkansas Water Resources Center Technical Reports
Bottom sediments, suspended sediments, and water were sampled along 130 miles of the Buffalo River in northern Arkansas. The water and acid extracts of the suspended sediments and the minus 95 mesh fraction of the bottom sediments were analyzed by atomic absorption spectrometry. All samples were analyzed for Na, K, Mg, Ca, Zn, Cd, Cu, Pb, Fe, Co, Cr, Ni, and Mn. Selected bottom samples also were analyzed by As, Hg, and Zr. Zr was determined by x-ray fluorescence. Li and Sr were determined for selected water and suspended sediment samples. There is a general decrease downstream in Fe, Cu, …
Survival And Growth Rate Of Channel Catfish As A Function Of Dissolved-Oxygen Concentration, R. W. Raible
Survival And Growth Rate Of Channel Catfish As A Function Of Dissolved-Oxygen Concentration, R. W. Raible
Arkansas Water Resources Center Technical Reports
Channel catfish were raised in water-recirculating systems for several periods of about six months duration each. Initial stock was fingerling size fish (10 to 20 grams). At dissolved-oxygen levels below 2.5 parts per million, mortality was high. Fish raised in tanks held at dissolved-oxygen levels between 3.0 and 6.8 parts per million showed increased gains of weight for each increment of added oxygen. Weight gains were as much as 50 percent higher at 6.8 parts per million compared with weights at 3.0 parts per million. Feed conversion was good in all cases. When feeding was limited to demand, feed conversion …
Movement Of Pesticides In The Soil Water Fertilizer System, H. Don Scott
Movement Of Pesticides In The Soil Water Fertilizer System, H. Don Scott
Arkansas Water Resources Center Technical Reports
A theoretical and experimental study of the transport of pesticides was conducted in several Arkansas soils with metribuzin, a herbicide. In a field study, chloride and metribuzin were applied to a Captina silt loam under maximum leaching conditions and their redistribution was compared with that of soil water. Metribuzin was found in significantly detectable quantities to a depth of 61 cm; the largest concentrations were detected in the surface 23 cm and particularly in the 0-5 cm increment. Two days after application 72.6 and 33.6% could be detected in the vegetation and no-vegetation plots. The metribuzin half life was 7.88 …
Pathogenic Free-Living Amoebae In Arkansas Recreational Waters, Leon W. Bone, David A. Becker
Pathogenic Free-Living Amoebae In Arkansas Recreational Waters, Leon W. Bone, David A. Becker
Arkansas Water Resources Center Technical Reports
Selected recreational waters of Arkansas were sampled for pathogenic free-living limax amoebae. Water quality parameters were determined for correlation with amoebic population densities and species diversity. Cultural criteria and animal inoculation revealed no pathogenic strains. The feasibility of introduction and/or induction of pathogenic amoebic strains by environmental factors necessitates further ecological investigaitons.
Biochrome Analysis As A Method For Assessing Phytoplankton Dynamics Phase Ii, Richard L. Meyer
Biochrome Analysis As A Method For Assessing Phytoplankton Dynamics Phase Ii, Richard L. Meyer
Arkansas Water Resources Center Technical Reports
Selected chemical, physical and biological parameters were determined for a man-made lake, Beaver Lake, on the White River of Arkansas and Missouri. The research program determined the qualitative and quantitative aspects of the temporal and spatial distribution of the algal subcommunities. It was determined that the epipelic, epilithic, epizooic and metaphytic subcommunities had little influence on the euplanktonic subcommunity. The relationship between the qualitative and quantitative analysis of the biochromes chlorophyll-a, -b, and -c and the phytoplankton species clustered into biochrome sets is discussed. The temporal and spatial distributional patterns of temperature, oxygen, ammonia-N, nitrate-N, orthophosphate-P and silicates are described …
Heat And Moisture Conduction In Unsaturated Soils, J. A. Havens, R. E. Babcock
Heat And Moisture Conduction In Unsaturated Soils, J. A. Havens, R. E. Babcock
Arkansas Water Resources Center Technical Reports
Mathematical models are developed for the prediction of heat transfer from hot water pipes buried in the soil. Heat transfer in the absence of moisture transfer is described as a function of the difference between the temperature of the pipe and the temperature of the soil surface. The energy balance is used to determine the longitudinal temperature distribution of the water. The method is extended to describe a system of equally spaced, parallel buried pipes. Soil temperature profiles around the pipes are presented. The model is used to calculate the land area that can be heated by an underground piping …
Sodium, Potassium, Calcium And Magnesium Content Of Northwest Arkansas Rain Water In 1974, G. H. Wagner
Sodium, Potassium, Calcium And Magnesium Content Of Northwest Arkansas Rain Water In 1974, G. H. Wagner
Arkansas Water Resources Center Technical Reports
No abstract provided.
Final Report: Buffalo National River Ecosystems, R. E. Babcock, H. C. Macdonald, D. G. Parker, Joe F. Nix, Kenneth F. Steele, Richard L. Meyer, R. W. Raible, D. A. Becker, R. V. Kilambi, E. H. Schmitz
Final Report: Buffalo National River Ecosystems, R. E. Babcock, H. C. Macdonald, D. G. Parker, Joe F. Nix, Kenneth F. Steele, Richard L. Meyer, R. W. Raible, D. A. Becker, R. V. Kilambi, E. H. Schmitz
Arkansas Water Resources Center Technical Reports
The objective of this study was to sample the Buffalo River on a seasonal basis for a year, in order to determine whether any potential water quality problems existed.
Environmental Evaluation Report Onn Various Completed Channel Improvement Projects In Eastern Arkansas, Edward E. Dale Jr., Thomas M. Buchanan, Richard L. Meyer, Robert T. Huffman
Environmental Evaluation Report Onn Various Completed Channel Improvement Projects In Eastern Arkansas, Edward E. Dale Jr., Thomas M. Buchanan, Richard L. Meyer, Robert T. Huffman
Arkansas Water Resources Center Technical Reports
The objective of this report is to evaluate the beneficial and adverse effects that certain channel improvement projects have had on the natural or man-made environments of selected areas in eastern Arkansas. This evaluation will be used as a baseline for determining the immediate and long-term effects that a project may have on the existing environment of the Village Creek Basin.
Selected Aspects Of The Limnology Of Zooplankton In Beaver And Degray Reservoirs, Arkansas, With Emphasis On The Development Of A Method For The Estimation Of Zooplankton Biomass, Eugene H. Schmitz, John T. Mccraw, Pamela J. Williams
Selected Aspects Of The Limnology Of Zooplankton In Beaver And Degray Reservoirs, Arkansas, With Emphasis On The Development Of A Method For The Estimation Of Zooplankton Biomass, Eugene H. Schmitz, John T. Mccraw, Pamela J. Williams
Arkansas Water Resources Center Technical Reports
No abstract provided.
Model For Estimating The Probability Of Crop Production For Ginkgo Biloba L., Michael I. Johnson
Model For Estimating The Probability Of Crop Production For Ginkgo Biloba L., Michael I. Johnson
Journal of the Arkansas Academy of Science
Mature female Maidenhair trees (Ginkgo biloba L.)have been observed to produce seed dispersal units in some years and none in other years. A temperature and/or photoperiod flowering threshold is suggested. Daily temperatures and daylengths at five Ginkgo sites in continental U.S. for January-April 1964-1974 were evaluated. A computer program was designed to estimate daily photothermal equivalent (PTE = temperature and photoperiod), and the magnitude and duration of the PTE in relation to a series of photothermal constants. Use of the data from production and nonproduction years provided a mathematical model for prediction of dispersal unit production. The model was tested …
Relationship Of Lead Mineralization And Bottom Sediment Composition Of Streams, Ponca-Boxley District, Arkansas, William S. Bowen, Kenneth F. Steele
Relationship Of Lead Mineralization And Bottom Sediment Composition Of Streams, Ponca-Boxley District, Arkansas, William S. Bowen, Kenneth F. Steele
Journal of the Arkansas Academy of Science
Samples from tributaries draining known mineralized areas contain considerably more lead than those from the main stream. The unique sediments (i.e. lead rich) from the tributaries are quickly diluted in the main stream to background levels. The lead content of the sediments from the tributaries apparently is controlled by the presence of lead-rich clasts. Sorption of lead by iron oxide coating grains is more significant in the main stream because the unique clasts are diluted. The mineralization also increases zinc and cadmium levels in the sediments. The concentration of calcium is controlled largely by the presence of limestone, whereas the …
Calico Rock Sandstone Member Of The Everton Formation (Ordovician), Northern Arkansas, Raymond W. Suhm
Calico Rock Sandstone Member Of The Everton Formation (Ordovician), Northern Arkansas, Raymond W. Suhm
Journal of the Arkansas Academy of Science
Surface and subsurface stratigraphic studies in northeastern Arkansas show the Calico Rock Sandstone (Middle Ordovician) to be a lobate sand body up to 200 ft thick. The environment of deposition is considered from a study of grain characteristics, ripple marks, subjacent and superjacent units and unpublished isopachous maps. The data indicate the Calico Rock Sandstone formed in a transgressing Everton sea as a barrier island and near shore sand complex. The quartz sand was derived from a northern source and was distributed by southwestward flowing longshore currents.
Occurrence Of The Puma, Felis Concolor, From Svendsen Cave, Marion County, Arkansas, William L. Puckette
Occurrence Of The Puma, Felis Concolor, From Svendsen Cave, Marion County, Arkansas, William L. Puckette
Journal of the Arkansas Academy of Science
A partial skeleton including fragmental skull and mandibles of the puma, Felis concolor, was recovered from Svendsen Cave, Marion County, Arkansas. The remains are thought to be of Late Pleistocene (Wisconsin) or Sub-recent age. Fossil records of the puma are rare and only one other Pleistocene or Sub-recent site in Arkansas, Conard Fissure, has yielded remains which could be assigned to this large felid.
Pole Stars Of Other Planets, Paul C. Sharrah
Pole Stars Of Other Planets, Paul C. Sharrah
Journal of the Arkansas Academy of Science
The north celestial pole of the Earth and the other planets is discussed. Right ascension and declination information on the location of the poles on the celestial sphere is summarized. The name of the brightest visible star near each pole is given and the special case of Uranus is discussed.
Guidelines For Authors, Academy Editors
Guidelines For Authors, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.
An Empirical Study Of Selected Causes And Effects Of Semirigid Prices In The Petroleum Refining Industry With Emphasis On The Period 1963 Through 1972, Robert Eugene Feller
An Empirical Study Of Selected Causes And Effects Of Semirigid Prices In The Petroleum Refining Industry With Emphasis On The Period 1963 Through 1972, Robert Eugene Feller
Graduate Theses and Dissertations
The premise of this study is that certain policies within and without the petroleum industry have interacted to produce semirigid industry prices. One effect of this price rigidity is the inflexibility that is passed on to costs whenever the traditional joint-cost-accounting allocation (based on relative market value) is used in conjunction with these prices.
In studying the problem, activities and policies which combined to cause artificial price restraints in the petroleum-refining industry from 1963 to 1972 were reviewed. The accounting and economic implications and the effect on refinery investment of the resulting semirigid prices were investigated.
Published wholesale gasoline prices …
Sodium, Potassium, Calcium And Magnesium Content Of Northwest Arkansas Rain Water In 1973 And Trace Metal Analyses Of 1974 Rains, G. H. Wagner, R. W. Holloway
Sodium, Potassium, Calcium And Magnesium Content Of Northwest Arkansas Rain Water In 1973 And Trace Metal Analyses Of 1974 Rains, G. H. Wagner, R. W. Holloway
Arkansas Water Resources Center Technical Reports
No abstract provided.
Build-Up Of Mineral Content In Lake Dardanelle And The Effect On Zooplankton, Tom N. Palko
Build-Up Of Mineral Content In Lake Dardanelle And The Effect On Zooplankton, Tom N. Palko
Arkansas Water Resources Center Technical Reports
No abstract provided.
Distribution Of Trace Metals In A Warm Water Release Impoundment, J. Nix
Distribution Of Trace Metals In A Warm Water Release Impoundment, J. Nix
Arkansas Water Resources Center Technical Reports
A water quality study of the DeGray Reservoir, Arkansas, was conducted beginning immediately following the beginning of impoundment through the first year in which the reservoir was operated near normal pool elevation. DeGray Reservoir is the first major dam in Arkansas to be equipped with upper level release capabilities. Temperature, dissolved oxygen, and turbidity were measured in situ at stations located over the old river channel. Samples were taken from selected levels within the water column at each station and analyzed for the following parameters: pH, sodium, potassium, calcium, magnesium, nitrate, phosphate, sulfate, chloride, fluoride, alkalinity, COD, iron, manganese, copper, …
Biochrome Analysis As A Method For Assessing Phytoplankton Dynamics Phase I, Richard L. Meyer
Biochrome Analysis As A Method For Assessing Phytoplankton Dynamics Phase I, Richard L. Meyer
Arkansas Water Resources Center Technical Reports
Selected chemical, physical and biological parameters were determined for a man-made lake, Beaver Lake, on the White River of Arkansas and Missouri. The research program determined the qualitative and quantitative aspects of the temporal and spatial distribution of the algal subcommunities. It was determined that the epipelic, epilithic, epizooic and metaphytic subcommunities had little influence on the euplanktonic subcommunity. The relationship between the qualitative and quantitative analysis of the biochromes chlorophyll-a, -b, and -c and the phytoplankton species clustered into biochrome sets is discussed. The temporal and spatial distributional patterns of temperature, oxygen, ammonia-N, nitrate-N, ortho phosphate-P and silicates are …
Limnetic Zooplankton Dynamics In Beaver Reservoir Including An Inventory Of Copepod Species And An Evaluation Of Vertical Sampling Methods, Eugene H. Schmitz
Limnetic Zooplankton Dynamics In Beaver Reservoir Including An Inventory Of Copepod Species And An Evaluation Of Vertical Sampling Methods, Eugene H. Schmitz
Arkansas Water Resources Center Technical Reports
There can be little doubt that the development of primary food sources (i.e. plankton) is an important factor contributing to fish production. Applegate and Mullan (1968) report that an exceptional sport fish harvest is generally associated with the development of new reservoirs, although the precise reasons for such interrelations are not known. Kramer and Smith (1962) demonstrated the tendency of bass fingerlings to feed on Cladocera in proportion to the latter's abundance, and Hodson (1966) reported the same basic pattern for largemouth and spotted bass fingerlings in Beaver Reservoir. Applegate and Mullan (1969) analyzed the digestive tract contents of larval …
Effects Of Mosquito Control Chemicals On Aquatic Fauna, J. L. Lancaster Jr., M. V. Meisch
Effects Of Mosquito Control Chemicals On Aquatic Fauna, J. L. Lancaster Jr., M. V. Meisch
Arkansas Water Resources Center Technical Reports
No mosquito abatement districts have ever been organized in Arkansas. Mosquito control efforts have been largely adulticiding operations by either aerial application or ground thermal fogging machines. Practically no chemical applications have been directed at the larval stage in residual water in ditches and depressions from which adult populations arise. Some larviciding with ethyl parathion has been done in ricefields. Although the treatment is very effective in mosquito reduction, voluntary treatment has not been completely successful. Because relatively little insecticide has been used as a larvicide in Arkansas, it was possible to evaluate the effect of recommended larvicides on non-target …
Automation Of The Continuous Coagulation Monitor, Dee Mitchell, James J. Oskowis
Automation Of The Continuous Coagulation Monitor, Dee Mitchell, James J. Oskowis
Arkansas Water Resources Center Technical Reports
The development of automation in the past 50 years has paralleled the accelerating growth of today’s vast technological society. Automatic control systems are indispensable extensions of man's brain that enable him to monitor and regulate his complex environment. The principles of automatic control have a wide range of applications and interests in virtually every scientific field. The need for automatic control systems in vital applications of environmental engineering is both real and urgent. Extensive pollution has resulted in unavoidable water re-use and in the inevitable establishment of stringent effluent standards. Both water and wastewater treatment processes have necessarily become more …
Limnological, Ichthyological, And Parasitological Investigations On Arkansas Reservoris In Relation To Water Quality, John S. Carter, Carl E. Hoffman, Larry L. Olmsted, Raj V. Kilambi, Donald G. Cloutman, David A. Becker
Limnological, Ichthyological, And Parasitological Investigations On Arkansas Reservoris In Relation To Water Quality, John S. Carter, Carl E. Hoffman, Larry L. Olmsted, Raj V. Kilambi, Donald G. Cloutman, David A. Becker
Arkansas Water Resources Center Technical Reports
Lake Fort Smith, a 525 acre (212 ha) reservoir, was impounded in 1936 as a water supply for the city of Fort Smith. The reservoir is located on Clear Creek (Frog Bayou), a tributary of the Arkansas River, in the Boston Mountains 28 miles (45 km) northeast of the city of Fort Smith in Crawford County, Arkansas. A map and morphometric characteristics of Lake Fort Smith are given in Fig. 1 and Table I (Hoffman, 1951; Nelson, 1952). In 1956 Lake Shepherd Springs, a 750 acre (304 ha) impoundment, was created one mile upstream of Lake Fort Smith (Rorie, 1961). …
Physical Meaning Of The Field H, H. E. Mccloud
Physical Meaning Of The Field H, H. E. Mccloud
Journal of the Arkansas Academy of Science
Through the introduction of the concept of magnetic charge the physical meaning of the magnetic field H is established within the rationalized MKS system of units
Biostratigraphic And Lithostratigraphic Analysis Of The Hindsville Limestone (Mississippian) In Northwestern Arkansas, Robert C. Grayson Jr.
Biostratigraphic And Lithostratigraphic Analysis Of The Hindsville Limestone (Mississippian) In Northwestern Arkansas, Robert C. Grayson Jr.
Journal of the Arkansas Academy of Science
Several lithofacies can be recognized within the Hindsville Limestone (Mississippian) in its type area near Hindsville, Madison County, Arkansas. Lithofacies are based on petrographic analysis of matrix and constituent particles, particularly ooliths and skeletal grains. Hindsville deposition began with skeletal calcilutite incorporating chert rubble from the underlying Boone Formation. Increasing energy produced a sequence of skeletal calcarenites and oolites, and the end of Hindsville deposition was marked by a return to impure skeletal calcilutite. Conodonts recovered from the Hindsville Limestone include species of Cavusgnathus and Gnathodus. On the basis of reported ranges of these elements, the Hindsville appears to correlate …
Faces, Edges, Vertices Of Some Polyhedra, Charles H. Harbison
Faces, Edges, Vertices Of Some Polyhedra, Charles H. Harbison
Journal of the Arkansas Academy of Science
A proof that: for any given polyhedron so shaped that every closed non-self intersecting broken line composed of edges of the polyhedron divides the surface of the polyhedron into precisely two disjoint regions each of which is bounded by the closed broken line, v - e + f = 2, where v is the number of vertices of the polyhedron, e the number of edges and f the number of faces.
Environmental Evaluation Report On The Big Mulberry Creek Basin In Franklin, Madison, Newton, Johnson And Crawford Counties, Arkansas, Edward E. Dale Jr.
Environmental Evaluation Report On The Big Mulberry Creek Basin In Franklin, Madison, Newton, Johnson And Crawford Counties, Arkansas, Edward E. Dale Jr.
Arkansas Water Resources Center Technical Reports
The environmental evaluation report which follows is based on information supplied by the Corps of Engineers, Little Rock District, available literature, field observations made during the summer of 1972, and results of research now in progress on natural features of the Big Mulberry Basin. Since most major dams, levees, and flood retarding structures now in existence in the Ozarks have been constructed since about 1940, opportunities to make long term studies of their effects have been limited. Also, the natural vegetation, fauna, and archeology of the Big Mulberry Basin have not been extensively investigated, but available sources provide enough information …
Guidelines For Authors, Academy Editors
Guidelines For Authors, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.