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Articles 391 - 420 of 440
Full-Text Articles in Chemistry
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.
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.
Analytical Modeling And Simulation For Investigation Of A Digital Gas Filter Correlation Radiometer, Catherine P. Mcgowan
Analytical Modeling And Simulation For Investigation Of A Digital Gas Filter Correlation Radiometer, Catherine P. Mcgowan
Electrical & Computer Engineering Theses & Dissertations
This thesis investigates a digital gas filter correlation radiometer called the Tropospheric Radiometer for Atmospheric Chemistry and Environmental Research (TRACER), which will be used to remotely measure carbon monoxide at three levels in the troposphere. The nadir-viewing radiometer measures the differential absorption of radiation through the atmosphere at 4.67@m and 2.33pm wavelengths. This thesis develops an analytical model of the TRACER measurement process to evaluate the effect of varying certain system parameters on the measurement. The independent sampling criterion and the response of linear systems to random signals are explained. A parametric simulation model is also developed to evaluate the …
Trace Elements In Estuarine And Coastal Waters: U.S. Studies From 1986-1990, Gregory A. Cutter
Trace Elements In Estuarine And Coastal Waters: U.S. Studies From 1986-1990, Gregory A. Cutter
OES Faculty Publications
The use of specialized analytical techniques, field studies, controlled laboratory experiments, and geochemical modeling have allowed U.S. investigators to expand our understanding of trace element cycling in coastal waters and estuaries. Considerable emphasis has been placed on quantifying the flux of trace elements within and through the coastal zone. In addition, substantial progress has been made in identifying the chemical speciation of many trace elements, providing a linkage between the geochemical and biochemical behavior of these elements. Another significant advance has been the use of trace elements as tracers of geochemical processes and water masses in the coastal environment.
Hydrogen Sulfide And Radon In And Over The Western North Atlantic Ocean, T. W. Andreae, Gregory A. Cutter, N. Hussain, J. Radford-Knoery, M. O. Andreae
Hydrogen Sulfide And Radon In And Over The Western North Atlantic Ocean, T. W. Andreae, Gregory A. Cutter, N. Hussain, J. Radford-Knoery, M. O. Andreae
OES Faculty Publications
Atmospheric measurements of radon and hydrogen sulfide, and seawater measurements of total sulfide, free sulfide, and carbonyl sulfide, were made on a cruise in the western North Atlantic Ocean (October 24 to November 9, 1989). Measured values for 222Rn ranged from 3 to 70 pCi m−3, those for atmospheric hydrogen sulfide from 1 to 85 parts per trillion, and those for dissolved total and free sulfide in seawater from 33 to 930 pmol L−1 and 0 to 73 pmol L−1, respectively. A positive correlation between 222Rn and atmospheric H2S was observed. …
Leaf Diseases Of Wheat, R. Loughman, Geoff Thomas, J. A. Bathgate, W. R. Smith
Leaf Diseases Of Wheat, R. Loughman, Geoff Thomas, J. A. Bathgate, W. R. Smith
Experimental Summaries - Plant Research
Trial 90PE10
Strategic variety mixtures to reduce septoria diseases of wheat. Evaluation of wheat lines for suitability to mixing for septoria control.
Location: Mt. Barker Research Station
To determine components of partial resistance to both Septoria species to ensure that lines with components that are complimentary are chosen for evaluation as mixtures for Septoria control.
Trial 90MT12 and 90ME10
Assessing effects of a paired variety mixture to reduce Septoria.
Location: Borden and Mt Barker Research Station.
To assess the effects of a variety mixture on Septoria diseases.
Trial 90MT11 and 90JE9
Evaluating variety mixtures to reduce septoria, using a range …
Cranola Rapseed Variety Assessment. Cranola Agronomy. Linseed. Tillage., J. D. Warren
Cranola Rapseed Variety Assessment. Cranola Agronomy. Linseed. Tillage., J. D. Warren
Experimental Summaries - Plant Research
Trial 90AB15. 90N68, 90EB39
Canola : assessment of early maturing Stage 2 lines.
Location: Katanning, Newdegate Research Station, East Beverley Annex
Production of Canola in medium rainfall zones offers the opportunity for a rapid expansion of the industry. However presently recommended varieties take too long to mature for the area's shorter growing season. The Stage 2 trials assess Canola lines selected on the basis of earliness from the remnants of Dr Roy's now defunct rapeseed breeding programme as well as selections from Eastern States breeding programmes. The trials arc conducted at three sites to account for environmental effects on cultivar …
Weed Control In Crops And Pasture., J. Buckley
Weed Control In Crops And Pasture., J. Buckley
Experimental Summaries - Plant Research
Trial 90WH74
Crop establishment trial
Location: Wongan Hills Research Station.
To assess the effect of timing of roundup and sprayseed application and cultivation on crop growth.
Trial 90AB19
Ryegrass control in wheat using slow release trifluralin.
Location: Katanning.
To compare 2 experimental formulations of controlled release trifluralin at 4 rates and 2 timings with some commonly used herbicides for the control of ryegrass in wheat.
Trial 90ME84
Early application of 2, 4-D to wheat.
Location: Corrigin.
To assess the use of 2,4-D.amine at early times of application for the control of broadleaf weeds in wheat.
Trial 90WH92
Early application of …
Phosphorus And Sulphur Nutrition Of Pastures In High Rainfall Areas., M. D. Bolland, M. F. Clarke
Phosphorus And Sulphur Nutrition Of Pastures In High Rainfall Areas., M. D. Bolland, M. F. Clarke
Experimental Summaries - Plant Research
J.S.Yeates and M.F.Clarke started these experiments. In January 1990 M.D.A. Bolland replaced J.S. Yeates (who became Regional Manager of the Northern Agricultural Region) as the Research Officer responsible for the management of the long-term experiments, and to continue the research on the topic.
In the experiments the fertilizers wee applied in autumn (March-April) in the years listed in the tables.
Trial 80AL4
Location: Cuthbert.
A new experiment was started in 1989 to compare two partially acidulated rock phosphate (PARP) fertilizers with ordinary (single) superphosphate (OSP).
Trial 84AL32
Location: Denmark
The fertilizers compared are ordinary (single) superphosphate (OSP). New (pre 1990) …
Investigating Poor Pasture Productivity., J. W. Bowden, R. J. Lunt, C. Broun
Investigating Poor Pasture Productivity., J. W. Bowden, R. J. Lunt, C. Broun
Experimental Summaries - Plant Research
Trial 90N06
Location: West Dale
To determine the reason for poor pasture productivity in medium rainfall zone. Specifically why the pastures are dominated by the poorly productive species Trifolium suffocatum and why there was a large response to phosphorous fertilizer at 50 ppm P in the soil.
Agronomic Practices To Improve Or Maintain The Protein Content Of High Yielding, Long Season Wheats., Wayne Smith
Agronomic Practices To Improve Or Maintain The Protein Content Of High Yielding, Long Season Wheats., Wayne Smith
Experimental Summaries - Plant Research
Trial 90SG8, 90SG9, 90ES9, 90ES11, 90MT8, 90KO2
Wheat variety * Time of sowing
Location: Salmon Gums Research Station, Mt. Ridley, East Gibson, Mt Barker Research Station, Kojaneerup Research Station
The aim is to define the optimum heading/flowering date on the South Coast. This trial also provides information on the performance of the varieties and new cross-breds at various sowing times.
Trial 90E10, 90ES12, 90ES13, 90ES14, 90ES15, 90ES16, 90SG10, 90SG11, 90MT10, 90KO3, 90KO4
Wheat protein on the South Coast
Location: Esperance Downs Research Station, Gibson, Neridup, Mt Ridley, Salmon Gums Research Station, Mt Barker Research Station, Kojaneerup Research Station
The Australian …
Development And Management Of Cattle Pastures In The High Rainfall Zone., Tony Albertsen
Development And Management Of Cattle Pastures In The High Rainfall Zone., Tony Albertsen
Experimental Summaries - Plant Research
Trial 87V8
Development and management of cattle pastures in the high rainfall zone.
To compare the effect of pasture species, pasture management and grazing management on pasture quantity, quality and cattle production.
Phalaris evaluation
In 1989 ninety three lines of Phalaris agrundinacea backcross with P. aquatica, bred by Dr. R.N. Oram (CSIRO Canberra) were drilled sown into unreplicated 10m single row plots at Vasse Research Station. In addition 7 controls (with two replications) were planted. Similar trials were planted by Mr. L. Cransberg (Albany) and Dr. R.N. Oram (Bendigo).
Evaluation of annual and short term rotation ryegrass.
The increasing range …
Total Maximum Daily Loads And Waste Load Allocations For Las Vegas Bay: Rationale And Calulations, State Of Nevada: Division Of Environmental Protection
Total Maximum Daily Loads And Waste Load Allocations For Las Vegas Bay: Rationale And Calulations, State Of Nevada: Division Of Environmental Protection
Publications (WR)
In September 1987 the Nevada Division of Environmental Protection revised Water Quality Standards for Las Vegas Wash (LVW) and Lake Mead. Standards were set for chlorophyll-a and unionized ammonia in Las Vegas Bay (LVB) (NDEP 1987). The 1986 and 1987 LVB data showed non-achievement of both the chlorophyll-a and unionized ammonia standard which triggered an analysis of total phosphorus and total ammonia Total Maximum Daily Loads and Waste Load Allocations which are presented in this report. This report is separated into three sections: 1. 1987 Las Vegas Bay Water Quality Conditions and Seasonal Periodicity. 2. Concentration Estimates at Northshore Road …
Tactical Nitrogen Decisions For Wheat (And N Rates Trials), J. W. Bowden, R. J. Lunt
Tactical Nitrogen Decisions For Wheat (And N Rates Trials), J. W. Bowden, R. J. Lunt
Experimental Summaries - Plant Research
Trial 89NO77 (89NO76)
Location: Grass Valley.
History: 1984 Lupins.
1985/86 pasture legumes and about 100 kg super/ha.
1987 Wheat yield of 2.8 t/ha using 45 kg DAP/ha and 60 of urea 2-4 WAS.
1988 Gungurru lupins (27 kg/ha seed) yielding 1.9 t/ha using 80 kg super/ha.
Tactical nitrogen trials - summary of treatments required.
Trial 89NO77
Location: Meckering
Treatments existed of nitrogen and urea. Nitrogen was not applied at seeding. Urea was applied at seeding.
Trial 88No77
Tactical nitrogen trials. - summary of observations.
Location: Grass Valley.
Trial 89NO76
Hand harvest 23/11/1989.
Yield components for copper sufficient plots reps. I …
Pasture Agronomy., C. K. Revell
Pasture Agronomy., C. K. Revell
Experimental Summaries - Plant Research
Trial 89ME82
a. Medic establishment.
Establishing burr medic pastures with cereal cover.
Merredin
Trial 89SC19
b. Serradella - Potash response.
Response of serradella to potash fertilizer.
South Carrabin
Trial 89M44
c. Serradella/Grass competition
Effect of grass competition on production of serradella.
Merredin Research Station.
Trial 89SC HERB
d. Herbicide tolerance of Serradella.
Herbicide tolerance of Madeira serradella.
South Carrabin
New Block Badgingarra Rs Late Time Of Seeding., J. W. Bowden, R. J. Lunt
New Block Badgingarra Rs Late Time Of Seeding., J. W. Bowden, R. J. Lunt
Experimental Summaries - Plant Research
Trial 89BA33,
Location: Badgingarra
Based on a 1.5 t/ha potential yield, the strategic treatment was planned to be 120 kg urea/ha 4WAS. However, the crop was poorly established and so NH4NO3 was used in the hope of getting better tillering than would be possible with the slower release urea source. Gambling on equal dollars to urea for 2/3 N, but believe that twice as effective.
DAP was used to place nitrogen with the seed in case there was no rain of significance after seeding. This nitrogen (only 5 kg/ha) was probably lost with the rains of 20-28/7/89 (50 mm). Urea …
Tactical Nitrogen Decisions For Wheat (And Nitrogen Sources Rates And Times On Wheat), J. W. Bowden, R. J. Lunt
Tactical Nitrogen Decisions For Wheat (And Nitrogen Sources Rates And Times On Wheat), J. W. Bowden, R. J. Lunt
Experimental Summaries - Plant Research
Trial 89MO49
Location: Tenderloin, Brand Highway, Regan's Ford.
History:
1987 Aroona wheat with 70 kg DAP and 3 kg CuSO4 at seeding followed by 60 urea at 3WAS and another 40 urea at 6WAS. Yield was about 1.7 to 1.8 t/ha;
1988 Gungurru lupins with 120 kg super and manganese/ha yielded 1.9 t/ha. 350-400 ml Roundup/ha and one cultivation prior to seeding.
Permanganate Colorimetric Rapid Method For Chemical Oxygen Demand In Seawater, Myung Zoon Czae, Taekee Hong, Myung Hoon Kim
Permanganate Colorimetric Rapid Method For Chemical Oxygen Demand In Seawater, Myung Zoon Czae, Taekee Hong, Myung Hoon Kim
Chemistry & Biochemistry Faculty Publications
No abstract provided.
Cultivar Evaluation On Low Rainfall Heavy Textured Soils., Bradley Nutt
Cultivar Evaluation On Low Rainfall Heavy Textured Soils., Bradley Nutt
Experimental Summaries - Plant Research
a. Trial 88GE34
Cultivar evaluation in machine sown plots.
Location: NMRS
The higher seed yield of Serena compared to the other cultivars resulted in better early forage .production as well a legume dominated pasture.
b. Trial 88TS 63 and 88TS 65
Wheat yields following pastures.
Location: 88TS63 - Perenjori and 88TS65 - Three Springs.
There was no response to nitrogen in either biological yield or grain yield of wheat sown over volunteer based pasture at the Three Springs site. All pasture treatments resulted in similar wheat yields except for Sava because of poor control of the snail medic under the …
Sulfide In Surface Waters Of The Western Atlantic Ocean, Gregory A. Cutter, Christian F. Krahforst
Sulfide In Surface Waters Of The Western Atlantic Ocean, Gregory A. Cutter, Christian F. Krahforst
OES Faculty Publications
Using newly developed techniques, some preliminary data on hydrogen sulfide in surface waters of the western Atlantic have been obtained. Concentrations of total sulfide range from <0.1 to 1.1 nmol/L, and vary on a diel basis. At these concentrations, sulfide may affect the cycling of several trace metals via the formation of stable complexes. Production of sulfide in oxygenated seawater may occur through the hydrolysis of carbonyl sulfide or by sulfate reduction within macroscopic particles in the water column. Removal mechanisms can include oxidation, complexation with particulate trace metals, and metal sulfide precipitation. However, the temporal and spatial distributions suggest a complex set of processes governing the behavior of sulfide in the surface ocean.
Optimization Of The Tungstic Acid Denuder Technique For The Measurement Of Atmospheric Ammonia, Patricia Diane Roberts
Optimization Of The Tungstic Acid Denuder Technique For The Measurement Of Atmospheric Ammonia, Patricia Diane Roberts
Chemistry & Biochemistry Theses & Dissertations
Measurement of - atmospheric ammonia with the tungstic acid denuder technique is discussed. Characterization of denuder tubes for manual sampling in terms of, repeatability, reliability and the development of ammonia blank signals was determined. Field testing of the manual sampling apparatus was performed at ground test sites and in a biomass burn smoke plume. Ammonia emissions from biomass burning are discussed.
Dryland Pasture Legume Programme, C. K. Revell, G. Croker, J. Simmons, L. Heinrich
Dryland Pasture Legume Programme, C. K. Revell, G. Croker, J. Simmons, L. Heinrich
Experimental Summaries - Plant Research
1. Medic variety evaluation
a. Row Evaluation - 88ME122 - Merredin.
This method of assessment was used to test a range of new medic material originating from the South Australian Department of Agriculture.
b. Evaluation of burr medics on Morrel soils. - 88ME84 - Nokaning.
c. Evaluation of burr medics on Whitegum soils. 88ME85 - North Kellerberrin.
d. Evaluation of Santiago in low rainfall areas - 88ME86 - Mukinbudin.
e. Selection of early maturing M. murex. 88SC30 - Merredin.
f. Medic species evaluation - large plots. 88NO88 - Tammin.
g. Medic species evaluation - large plots. 85M43 - Merredin Research …
River Discharge Study, Laughlin, Nevada: Colorado River Model And Diffusion Study, B. Dennis Hugh, David L. Stringfield, Jill C. Bicknell, Robert A. Ryder, Clark County Sanitation District, Nevada
River Discharge Study, Laughlin, Nevada: Colorado River Model And Diffusion Study, B. Dennis Hugh, David L. Stringfield, Jill C. Bicknell, Robert A. Ryder, Clark County Sanitation District, Nevada
Publications (WR)
A water quality modeling study of the Mohave Reach of the Lower Colorado River (from Davis Dam to the Nevada/California Stateline) was conducted to evaluate potential water quality impacts resulting from a proposed Laughlin, Nevada wastewater effluent discharge. The study included four major components: (1) review of the current regulatory framework; (2) a field data collection program to document existing water quality conditions in winter, summer, and fall; (3) development and verification of far-field and near-field (mixing zone) water quality models; and (4) application of the models to project future river quality conditions for several treatment-discharge alternatives as well as …
Limnological Monitoring Data For Lake Mead During 1987: Technical Report No. 20, Larry J. Paulson
Limnological Monitoring Data For Lake Mead During 1987: Technical Report No. 20, Larry J. Paulson
Publications (WR)
Limnological monitoring was conducted in Las Vegas Bay and Boulder Basin from April to December of 1987. The purpose of the monitoring was to (i) document possible changes in water quality resulting from decreased phosphorus loading in Las Vegas Wash, and (ii) establish a data base for evaluating the adequacy of water quality standards.
River Discharge Study, Laughlin, Nevada: Field Survey Data, 1987, B. Dennis Hugh, David L. Stringfield, Jill C. Bicknell, Robert A. Ryder, Clark County Sanitation District, Nevada
River Discharge Study, Laughlin, Nevada: Field Survey Data, 1987, B. Dennis Hugh, David L. Stringfield, Jill C. Bicknell, Robert A. Ryder, Clark County Sanitation District, Nevada
Publications (WR)
A report of the first field data collection effort for the Laughlin River Discharge Study, conducted by Kennedy/Jenks/ChiIton in February, 1987, on the Mohave Reach of the Colorado River. This report also serves to transmit the laboratory analysis reports for all of the analyses performed and summary tables of the results. This report is organized as follows: 1. Field Conditions and Methodology 2. Summary of Sampling and Analysis Results 3. Deviations from the Proposed Sampling Program 4. Recommendations for Future Sampling 5. Attachments: A. Climatological Data B. Davis Dam Average Hourly Releases C. Laboratory Analysis Reports
Lake Mead Cover Enhancement Project, Jennifer Stevens Haley, Suzanne Leavitt, Larry Paulson, Donald H. Baepler
Lake Mead Cover Enhancement Project, Jennifer Stevens Haley, Suzanne Leavitt, Larry Paulson, Donald H. Baepler
Publications (WR)
Ninety-three wildlife agencies were surveyed for information on their attempts to improve fish habitat. In addition, an annotated bibliography including over 100 summaries was completed on: 1. largemouth bass cover requirements and preferences, 2. use and effectiveness of artificial cover, 3. aquatic plant introduction and species requirements for germination and establishment, 4. terrestrial plant introduction and species requirements for germination and establishment, and 5. nutrient exchange between sediment, aquatic plants, and water. A reconnaissance of existing terrestrial and aquatic vegetation was completed in June 1986 including the production of a video tape of the Nevada shoreline of Lake Mead. Cover …
Las Vegas Wash And Lake Mead Proposed Water Quality Standards: Revisions And Rationale, State Of Nevada: Division Of Environmental Protection
Las Vegas Wash And Lake Mead Proposed Water Quality Standards: Revisions And Rationale, State Of Nevada: Division Of Environmental Protection
Publications (WR)
Rationale of review and for proposed changes to the Nevada Pollution Control Regulations (NAC 445.1354, 445.1355, 445.1356, 455.1367, 445.1352, 445.1353, 445.1350, 445.1351) before the State Environmental Commission on June 23 and 24, 1987.
Raw Nutrient Data, Leanna Gail
Raw Nutrient Data, Leanna Gail
Publications (WR)
Data collected at various stations around Lake Mead. Includes information about substances present in various water samples.
N X P X Irrigation On Wheat - South Carabin, J W. Bowden
N X P X Irrigation On Wheat - South Carabin, J W. Bowden
Experimental Summaries - Plant Research
Trial 87M7.
Nx P x irrigation on wheat
Although no major effects of fertilizer on average seed size were noted, it was found that phosphate level had an effect on the distribution of seed sizes.
Location: South Carrabin.
Trial 87WH51
1987 rainfall.
Location: Wongan Hills Research Station.
A Proposal To Fertilize The Overton Arm And Gregg Basin Areas Of Lake Mead, Larry J. Paulson
A Proposal To Fertilize The Overton Arm And Gregg Basin Areas Of Lake Mead, Larry J. Paulson
Publications (WR)
Several limnological studies have been conducted in Lake Mead during the past decade. The recent studies clearly show that most of Lake Mead is deficient in nutrients, especially phosphorus, and very low in productivity. The reservoir-wide average total phosphorus concentration for 1981 - 1982 was only 9 mg/m3. This is below levels found In most oligotrophic lakes and reservoirs. Algal biomass, as measured by chlorophyll-a, averaged only 1.5 mg/m3. That also places Lake Mead in the oligotrophic range. Transparency, as measured by a Secchi disc, averaged 9-5 m in Lake Mead during 1981-1982. That far exceeds …