Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

University of Arkansas, Fayetteville

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 2161 - 2190 of 2433

Full-Text Articles in Physical Sciences and Mathematics

Evalution Of Drainage Tile To Alleviate Salt Building In Heavy Soils Irrigated With Brackish Water And Cropped With Rice And Soybeans, T. C. Keisling, J. T. Gilmour, H. D. Scott, A. M. Sadeghi, R. E. Baser Aug 1984

Evalution Of Drainage Tile To Alleviate Salt Building In Heavy Soils Irrigated With Brackish Water And Cropped With Rice And Soybeans, T. C. Keisling, J. T. Gilmour, H. D. Scott, A. M. Sadeghi, R. E. Baser

Technical Reports

The use of tile drains for alleviating soluble salt accumulation on silt loam soil was investigated during 1984. Although the chemical analyses of the floodwater and tile drainage water were very similar suggesting that the floodwater was moving to the tile drain, the overall results so far indicate that this is not a feasible solution owing to lack of significant drainage. Application of DRAINMOD utilizing soil and weather data from Arkansas showed no significant effluent from the tile drains for our experimental site during rice production. This was attributed to the extremely slow saturated hydraulic conductivity values for this particular …

Go to article

Laser-Photoacoustic Detection Of Water Pollutants, Gregory J. Salamo, Richard J. Anderson Mar 1984

Laser-Photoacoustic Detection Of Water Pollutants, Gregory J. Salamo, Richard J. Anderson

Technical Reports

We have investigated the potential of amplitude-modulation laser-photoacoustic scheme for the detection of trace pollutants in water. The technique has been found to be non-disturbing and easy-to-apply. In particular, the technique could be used to detect pollutants with a concentration corresponding to an absorption coefficient of 10-6cm-1. The sensitivity was found to be limited by a background signal resulting from light absorption by water. In addition to the amplitude-modulation scheme we also investigated the potential of a wavelength modulation scheme. Although this approach did reduce the background signal due to water absorption, we found the technique to be much more …

Go to article

Evaluation Of Sugar Cane Bagasse And Rice Straw As Process Substrates For The Production Of Ethyl Alcohol, Douglas B. Rivers, Gisella M. Zanin, George H. Emert Jan 1984

Evaluation Of Sugar Cane Bagasse And Rice Straw As Process Substrates For The Production Of Ethyl Alcohol, Douglas B. Rivers, Gisella M. Zanin, George H. Emert

Journal of the Arkansas Academy of Science

No abstract provided.

Go to article

Implications Of Hydrocarbon And Helium Gas Analyses Of Springs From The Ouachita Mountains, Arkansas, Randel T. Cox, Kenneth F. Steele Jan 1984

Implications Of Hydrocarbon And Helium Gas Analyses Of Springs From The Ouachita Mountains, Arkansas, Randel T. Cox, Kenneth F. Steele

Journal of the Arkansas Academy of Science

One hundred and three ground water samples (predominantly springs) were analyzed for headspace light hydrocarbon gases and helium. Four of the formations (Arkansas Novaculite, Bigfork Chert, Stanley Shale, and Womble) having the highest mean methane values are the only Ouachita Mountain facies to produce petroleum or exhibit marginally commercial production. This observation suggests that the mean methane values are useful as an indication of the relative hydrocarbon content of these formations Anomalous helium values are generally associated with mapped faults.

Go to article

Disposal Of Household Wastewater In Soils Of High Stone Content (1981-1983), E. M. Rutledge, C. R. Mote, D. T. Mitchell, M. S. Hirsch, M. D. Harper, H. D. Scott, C. L. Griffis Dec 1983

Disposal Of Household Wastewater In Soils Of High Stone Content (1981-1983), E. M. Rutledge, C. R. Mote, D. T. Mitchell, M. S. Hirsch, M. D. Harper, H. D. Scott, C. L. Griffis

Technical Reports

Four experimental filter fields were constructed with built-in monitoring equipment in Nixa soils. These soils contain many chert fragments and a fragipan about 60 cm below the soil surface. The fragipan restricts downward movement of water and is the designlimitingfeature. The four filter fields were: 1. A "standard" filter field, 76 cm deep. The bottom of the trench was in the fragipan. 2. A "modified standard" filter field, 30 cm deep. The bottom of the trench was above the fragipan. 3. A "modified pressure" filter field, 40 cm deep. The bottom of the trench was above the fragipan. In addition, …

Go to article

A Systematic Study To Reduce Trihalomethane Precursors In Little Rock Drinking Water By Combined Alum Coagulation-Powdered Activated Carbon Treatment, Ali U. Shaikh Jun 1983

A Systematic Study To Reduce Trihalomethane Precursors In Little Rock Drinking Water By Combined Alum Coagulation-Powdered Activated Carbon Treatment, Ali U. Shaikh

Technical Reports

Studies have been conducted to evaluate powdered activated carbon (PAC) as an agent for controlling trihalomethanes in drinking water. Laboratory studies indicate that PAC is highly efficient in removing free trihalomethanes in water within a few hours. The removal efficiency of humic acid, a known THM precursor, by PAC is considerably less. However, longer treatment time can remove the precursors quite significantly. Humic substances in surface water samples can also be removed by PAC.

Go to article

Effects Of Sewage Pollution In The White River, Arkansas On Benthos And Leaf Detritus Decomposition, Arthur V. Brown, Lawrence D. Willis, Peter P. Brussock May 1983

Effects Of Sewage Pollution In The White River, Arkansas On Benthos And Leaf Detritus Decomposition, Arthur V. Brown, Lawrence D. Willis, Peter P. Brussock

Technical Reports

Recently there has been much emphasis placed on the importance of leaf detritus processing to the energetics of stream invertebrates. This study was designed primarily to assess the effects of municipal effluent on the ability of a stream community to utilize leaf detritus, and secondarily to evaluate the extent of the pollution of the White River by the Fayetteville, Arkansas effluent discharge. Physical and chemical water quality, benthos, and fish were sampled periodically at one station upstream and two stations downstream from the discharge, and in the Richland Creek tributary. Processing of leaf detritus was studied at each site using …

Go to article

Chemistry Of The Springs Of The Ozark Mountains, Northwestern Arkansas, Kenneth F. Steele May 1983

Chemistry Of The Springs Of The Ozark Mountains, Northwestern Arkansas, Kenneth F. Steele

Technical Reports

Three lead-zinc mineralized areas of northern Arkansas were selected to study the effect of mineralization on ground water chemistry. The Ponca area has the largest amount of lead sulfide mineralization, the Zinc area has a significant amount of zinc silicate and zinc sulfide; whereas, the Rush area has zinc carbonate and zinc sulfide. A total of 143 samples were collected from these areas and analyzed for general water chemistry parameters including heavy metal The water quality of the area is generally good; however, a few springs exceed the drinking water standards for ammonia, nitrate, iron, manganese and lead. The surface …

Go to article

Causes Of Localized Copper Corrosion In Drinking Water Supplies, R. A. Sims, R. W. Raible May 1983

Causes Of Localized Copper Corrosion In Drinking Water Supplies, R. A. Sims, R. W. Raible

Technical Reports

Excessive amounts of copper have been observed in drinking water at certain installations on Lake DeGray and at isolated locations in the Arkadelphia area of Arkansas. A study of these installations was conducted to determine the source of the copper contamination. The supply water was very low in copper and therefore dissolution of the copper plumbing caused by low water pH and long residence times was determined to be the most probable source.

Go to article

Disposal Of Household Wastewater In Soils Of High Stone Content (1977-1980), E. M. Rutledge, C. R. Mote, M. S. Hirsh, H. D. Scott, D. T. Mitchell May 1983

Disposal Of Household Wastewater In Soils Of High Stone Content (1977-1980), E. M. Rutledge, C. R. Mote, M. S. Hirsh, H. D. Scott, D. T. Mitchell

Technical Reports

Two experimental septic tank filter fields were constructed with built-in monitoring equipment in Nixa soils. These soils contain many chert fragments and a fragipan about 60 cm deep which restricts downward water movement and is the design-limiting feature. The standard filter field (76 cm deep) was built into the fragipan and the modified standard filter field (30 cm deep) was placed above it. During 30 months' observation, the modified standard performed better than the standard filter field. Maximum rise of effluent in the standard and modified standard came within 11 and 19 cm of the soil surface, respectively. Performance of …

Go to article

Evaluation And Accessing Of Data For A Water Resources Simulator, Richard C. Peralta, Roberto Arce, Timothy Skergan Mar 1983

Evaluation And Accessing Of Data For A Water Resources Simulator, Richard C. Peralta, Roberto Arce, Timothy Skergan

Technical Reports

This report evaluates the availability of data needed to use a groundwater simulation model for real time conjunctive water management in the Arkansas Grand Prairie. It is assumed that the goal of such management is to protect existing groundwater rights by maintaining water levels so that wells do not go dry, even in time of drought. Sufficient hydrogeologic data exists to use the simulation model to predict the effect of known pumping rates on groundwater levels. Developing an optimal set of "target" levels and annually managing pumping to achieve those levels requires additional data: fall groundwater levels, degree of connection …

Go to article

Monitoring Of Groundwater Levels For Real-Time Conjunctive Water Management, Richard C. Peralta, Vince Mazure, Paul Dutram Mar 1983

Monitoring Of Groundwater Levels For Real-Time Conjunctive Water Management, Richard C. Peralta, Vince Mazure, Paul Dutram

Technical Reports

Water users in the Arkansas Grand Prairie wish to maintain sufficient groundwater levels to: insure adequate groundwater reserves for time of drought, protect themselves from litigation caused by wells going dry, and insure a sustained yield. Achievement of these goals requires regular measurement of groundwater levels. Review of monitoring practice and technology indicates that spring and fall measurements taken over the entire area using steel tape and acoustic device is preferred for most long range planning. Continuous monitoring is indicated for critical parts of the region where saturated thicknesses are small. Desirable attributes of a data collection/transmission system for such …

Go to article

The Effects Of Forest Harvest On Water Quality And Aquatic Life (Phase I), Edmond J. Bacon Mar 1983

The Effects Of Forest Harvest On Water Quality And Aquatic Life (Phase I), Edmond J. Bacon

Technical Reports

A long term study on the effects of clearcut forest harvest and regeneration was conducted in a representative watershed of the Ouachita National Forest. Fourteen water quality parameters were analyzed to characterize baseline water quality. Water quality was classified as excellent. A total of 350 quantitative benthic samples and 15 ultraviolet light trap samples yielded 173 species of macroinvertebrates. Mean densities of macroinvertebrates ranged from 4,800/m2 to 23,040/m2 and averaged 12,499/m2 in the upper Little Missouri River. Twenty-two quantitative collections of fishes were made at representative riffles and pools. The average biomass estimates for riffles and pools were 5.69 kg/ha …

Go to article

Nutrients And Acid In The Rain And Dry Fallout At Fayetteville, Arkansas (1980-1982), George H. Wagner, Kenneth F. Steele Mar 1983

Nutrients And Acid In The Rain And Dry Fallout At Fayetteville, Arkansas (1980-1982), George H. Wagner, Kenneth F. Steele

Technical Reports

Wet and dry fallout at Fayetteville, Arkansas have been collected separately and analyzed since April, 1980. The precipitation-weighted-average pH for two yearly periods of rainfall were 4.72 (6/80-5/81) and 4.75 (6/81-5/82). This corresponds to a concentration of the acid ion, H+, of about 18 parts per billion (ppb). Pure water in equilibrium with the CO2 of the air would have a pH of 5.65 (2.2 ppb of H+). The range of pH during this two year period was 3.86-7.74(140-0 ppb H+) for the rainfall. Aqueous extracts of the dry fallout were always in the 6.75-7.87 pH range, i.e., neutral to …

Go to article

A Survey Of Soils Irrigated With Arkansas River Water, John T. Gilmour, H. D. Scott, R. E. Baser Mar 1983

A Survey Of Soils Irrigated With Arkansas River Water, John T. Gilmour, H. D. Scott, R. E. Baser

Technical Reports

Interest in the use of Arkansas River water for irrigation has increased recently as land adjacent to the river is converted to crop production and river water is considered as an alternative to depleted underground supplies. Since the Arkansas River can contain elevated concentrations of sodium chloride, this study was designed to determine if soil conditions adverse to crop growth were developing where river water has been used. The impact of river water on sites where river water was used as either the sole source for up to 3 years or as a supplement to another surface source for up …

Go to article

Expansion Potential For Irrigation Within The Mississippi Delta Region, Robert N. Shulstad, Ralph D. May, Jon Mark Erstine, Blake N. Phillips, Billy E. Herrington Jr. Mar 1983

Expansion Potential For Irrigation Within The Mississippi Delta Region, Robert N. Shulstad, Ralph D. May, Jon Mark Erstine, Blake N. Phillips, Billy E. Herrington Jr.

Technical Reports

17.6 million acres, or 73 percent, of the Mississippi Delta Region is currently cropland and possesses the physical characteristics of slope, texture and soil type which are recommended for irrigation. Economic feasibility of expanding irrigation by flood, furrow and center pivot methods were examined under 24 scenarios representing two sets of crop prices, yield levels, production costs, opportunity costs and six crop rotations. Irrigation was economically feasible for 56 to 100 percent of the cropland across all scenarios. Approximately 88 percent of the cropland can be economically irrigated with flood or furrow in its present form, 8 percent yield highest …

Go to article

The Costs And Benefits Of Soil Erosion Control In The North Lake Chicot Watershed, Robert N. Shulstad, C. Tim Osborn, Alan D. Mcqueen Mar 1983

The Costs And Benefits Of Soil Erosion Control In The North Lake Chicot Watershed, Robert N. Shulstad, C. Tim Osborn, Alan D. Mcqueen

Technical Reports

Lake Chicot is divided by a levee into two basins, the high quality northern basin and the extremely polluted southern basin. Water quality in the northern basin of Lake Chicot is diminishing due to soil erosion. Costs for alternative control programs for the seventeen fare, 11,470 acre northern watershed were estimated. Twenty-nine combinations of rotations and best management practices were evaluated. Soil loss can be reduced almost 25 percent from 4.2 tons per acre to 3.2 tons per acre, while increasing net returns to farmers from $83.94 per acre to $107.28 per acre by altering present cropping patterns. A prohibition …

Go to article

Effects Of Sewage Pollution In The White River, Arkansas, Arthur V. Brown, Lawrence D. Willis, Peter P. Brussock Jan 1983

Effects Of Sewage Pollution In The White River, Arkansas, Arthur V. Brown, Lawrence D. Willis, Peter P. Brussock

Journal of the Arkansas Academy of Science

Recently there has been much emphasis placed on the importance of leaf detritus processing to the energetics of stream invertebrates. This study was designed primarily to assess the effects of municipal effluent on the ability of a stream community to utilize leaf detritus, and secondarily to evaluate the extent of the pollution of the White River by the Fayetteville, Arkansas, effluent discharge. Physical and chemical water quality and benthos were sampled periodically at one station upstream and two stations downstream from the discharge, and in the Richland Creek tributary. Processing of leaf detritus was also studied at each site using …

Go to article

Early Pennsylvanian Conodont-Ammonoid Biostratigraphy And The Witts Springs Problem, North-Central Arkansas, Mary Ann Eccher, Daniel J. Murdaugh, Wildon D. Hawkins Jan 1983

Early Pennsylvanian Conodont-Ammonoid Biostratigraphy And The Witts Springs Problem, North-Central Arkansas, Mary Ann Eccher, Daniel J. Murdaugh, Wildon D. Hawkins

Journal of the Arkansas Academy of Science

The Witts Springs Formation was proposed as a lithostratigraphic unit in north-central Arkansas to include the interval from a horizon equivalent to the base of the Prairie Grove Member, Hale Formation to the top of the Bloyd Formation, of the type Morrowan Series, northwestern Arkansas. The top of the Witts Springs Formation was regarded as being unconformably succeeded by the middle Pennsylvanian Atoka Formation. Recent investigation of this unit in its type area has shown that the presumed Atokan Sandstone is actually a unit confined to the Bloyd Formation. Thus, the type section of the Witts Springs in Searcy County, …

Go to article

Microcomputer-Assisted Colorimetric Determination Of Iron, A. M. Hoyt Jr. Jan 1983

Microcomputer-Assisted Colorimetric Determination Of Iron, A. M. Hoyt Jr.

Journal of the Arkansas Academy of Science

No abstract provided.

Go to article

Flat Plate Solar Thermal Collectors: A Comparison Of Efficiencies Of Various Collector Configurations, Rudolph J. Eichenberger Jan 1983

Flat Plate Solar Thermal Collectors: A Comparison Of Efficiencies Of Various Collector Configurations, Rudolph J. Eichenberger

Journal of the Arkansas Academy of Science

No abstract provided.

Go to article

The Application Of Laser Intracavity Absorption Detector To Gas Chromatography Of Trace Organic Pollutants In Water, Robert B. Green Dec 1982

The Application Of Laser Intracavity Absorption Detector To Gas Chromatography Of Trace Organic Pollutants In Water, Robert B. Green

Technical Reports

A helium-neon (HeNe) laser operating simultaneously at 3.39 um (infrared) and 0.63 um (visible) has been used as a selective detector for hydrocarbons in the effluent of a gas chromatograph. The infrared and visible laser transitions originate at the same energy level and are competitive. When a hydrocarbon enters the laser's resonant cavity, the 3.39 um energy is absorbed due to the C-H stretching vibration and the visible emission is enhanced. The visible laser emission is monitored with a photodiode as a quantitative measure of the concentration of the absorbing molecule. The minimum detectable concentration for propane using the double-beam …

Go to article

A Faunal And Seasonal Study Of The Aquatic Insects In Two Water Ecosystems In South Arkansas: Degray Reservoir And The Upper Cadda River, Robert T. Allen Oct 1982

A Faunal And Seasonal Study Of The Aquatic Insects In Two Water Ecosystems In South Arkansas: Degray Reservoir And The Upper Cadda River, Robert T. Allen

Technical Reports

The impounding of the lower Caddo River to create DeGray Reservoir radically changed the water habitats in that portion of the Caddo River. A number of new and different habitats were created by the lake. The objective of this study was to determine what, if any, differences existed between the aquatic insect biotas of DeGray Reservoir and the upper Caddo River. Four collecting stations along the shore of DeGray Reservoir and four stations along the upper Caddo River were selected as sampling sites. Collections were made at one month (March, April, Oct., Nov.) intervals or at two week intervals (May, …

Go to article

Effects Of Water On The Fate Of Herbicides In Irrigated Soils, Terry L. Lavy Aug 1982

Effects Of Water On The Fate Of Herbicides In Irrigated Soils, Terry L. Lavy

Technical Reports

The wide use of soil-applied herbicides necessitates an understanding of their fate in soil if we are to use them in the most beneficial manner. All herbicides have some degree of water solubility and the field performance of many are dependent on ample, timely availability of soil moisture. It is important that different aspects of soil-herbicide-water interactions be thoroughly investigated. An excess use of water for irrigation purposes can result in the downward movement of herbicides in the soil profile. Subsoils are less adsorptive and a decreased degradation potential exists when herbicides move below the top 15 cm. In sandy …

Go to article

Atrazine Degradation, Sorption And Bioconcentration In Water Systems, Duane C. Wolf, Ramon L. Jackson Aug 1982

Atrazine Degradation, Sorption And Bioconcentration In Water Systems, Duane C. Wolf, Ramon L. Jackson

Technical Reports

The herbicide atrazine is used extensively to control broadleaf and grass weeds in such crops as sorghum and corn. A small portion of the atrazine may be lost from the area of application by surface runoff and could enter a stream or lake. The objective of this study was to evaluate atrazine degradation, sorption, and bioconcentration in watersediment systems. The results indicated that sediments with lower pH values and higher organic matter levels adsorbed higher levels of atrazine than sediments with neutral pH values and lower organic matter levels. Microbial decomposition of the herbicide was slow under the conditions of …

Go to article

Stratigraphy Of A Pennsylvanian Deltaic Sequence In Russellville, Arkansas, Christopher F. Moyer, Ken Fritsche Jan 1982

Stratigraphy Of A Pennsylvanian Deltaic Sequence In Russellville, Arkansas, Christopher F. Moyer, Ken Fritsche

Journal of the Arkansas Academy of Science

No abstract provided.

Go to article

Preliminary Investigation Of Ground-Water Occurrence In The Atoka Formation Of Pope And Faulkner Counties, Arkansas, Wyndal M. Goodman, Albert E. Ogden Jan 1982

Preliminary Investigation Of Ground-Water Occurrence In The Atoka Formation Of Pope And Faulkner Counties, Arkansas, Wyndal M. Goodman, Albert E. Ogden

Journal of the Arkansas Academy of Science

One hundred and twelve wells having drillers' logs were studied in Pope and Faulkner counties. Sixty-six of the wells produced water from shales and siltstones of the Atoka Formation while 46 produced from interbedded Atoka sandstones. Drillers' estimated well yields ranged from 1 to 100 gpm, but the median yield was only 9 gpm. Well depths ranged from 30 to 337 feet with a median depth of 100 feet. Ground-water is usually obtained from a series of low-producing confined aquifers of low artesian pressure. Pressure head and production were shown, statistically (a = .01), to decrease with increasing well depth. …

Go to article

Reconnaissance Of The Bedrock Aquifers And Groundwater Chemistry Of Crawford, Franklin, And Sebastian Counties, Arkansas, Samuel R. Rothermel, Wyndal M. Robison, Julie L. Wanslow, James R. Musgrove, Daryll Saulsberry, Albert E. Ogden Jan 1982

Reconnaissance Of The Bedrock Aquifers And Groundwater Chemistry Of Crawford, Franklin, And Sebastian Counties, Arkansas, Samuel R. Rothermel, Wyndal M. Robison, Julie L. Wanslow, James R. Musgrove, Daryll Saulsberry, Albert E. Ogden

Journal of the Arkansas Academy of Science

A ground water reconnaissance of Crawford, Franklin, and Sebastian counties was performed utilizing 122 wells having drillers' logs from bedrock aquifers. North of the Arkansas River, essentially all bedrock wells produce from the Atoka Formation. There are many low producing aquifers within the Atoka with a range in yield of 0.1 to 55 gpm, but having a median yield of only 2 gpm. Well depths range from 18 to 248 feet with a median of 122 feet. More water is generally obtained from the shale/siltstone aquifers than the sandstones due to more bedding-plane partings and more closely spaced fractures. Greater …

Go to article

Reconnaissance Of Ground-Water Resources Of Stone And Independence Counties, Arkansas, Albert E. Ogden, James R. Musgrove, Lisa Milligan Jan 1982

Reconnaissance Of Ground-Water Resources Of Stone And Independence Counties, Arkansas, Albert E. Ogden, James R. Musgrove, Lisa Milligan

Journal of the Arkansas Academy of Science

No abstract provided.

Go to article

Sr/Mg Ratios Of Pennsylvanian Limestone Units In Northwest Arkansas, George H. Wagner, Kenneth F. Steele, Doy L. Zachry Jan 1982

Sr/Mg Ratios Of Pennsylvanian Limestone Units In Northwest Arkansas, George H. Wagner, Kenneth F. Steele, Doy L. Zachry

Journal of the Arkansas Academy of Science

No abstract provided.

Go to article

First Prev Next Last