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Articles 16141 - 16170 of 17792
Full-Text Articles in Entire DC Network
The Long-Term Viability Of A Zero-Valent Iron Permeable Reactive Barrier, Stuart Cowburn
The Long-Term Viability Of A Zero-Valent Iron Permeable Reactive Barrier, Stuart Cowburn
Dissertations and Theses
Zero-valent iron permeable reactive barriers (PRB's) hold significant potential as a tool for groundwater remediation. Uncertainties remain, however, as to the effective lifetime of Fe0 barrier technology under full-scale operational conditions. Potential limits on barrier lifetime include reductions in permeability due to clogging by precipitates and oxidation of all Fe0 prior to the exhaustion of the contaminant source.
A 46 m long, 0.6 m wide, and 7.3 m deep Fe0 PRB was installed at the US Coast Guard Support Center, Elizabeth City, NC, in June 1996. The barrier was designed to remediate groundwater principally contaminated with Cr(VI) …
Late Quaternary Fossil Mammals And Last Occurrence Dates From Caves At Barahona, Puerto Rico, Donald A. Mcfarlane
Late Quaternary Fossil Mammals And Last Occurrence Dates From Caves At Barahona, Puerto Rico, Donald A. Mcfarlane
WM Keck Science Faculty Papers
Puerto Rico supported at least five genera of endemic terrestrial mammals in the late Quaternary, all of which are extinct. Whether these animals died out in the late Pleistocene, the mid-Holocene, or in post-Columbian time has not been established. This paper is the first attempt at radiometrically dating the 'last occurrences' of these taxa, together with the first unambiguous descriptions of localities reported by previous workers. Last occurrence dates for Nesophontes, Elasmodontomys and Heteropsomys are shown to be mid-Holocene and overlap with Amerindian occupation of the island. Acratocnus is known only from the late Pleistocene. No Puerto Rican taxon has …
Investigating Ground And Surface Water In The Republican River Basin Of Nebraska Using Water Chemistry And Environmental Isotopes, Jennifer J. Schellpeper
Investigating Ground And Surface Water In The Republican River Basin Of Nebraska Using Water Chemistry And Environmental Isotopes, Jennifer J. Schellpeper
School of Natural Resources: Dissertations, Theses, and Student Research
Recent legal battles concerning water use initiated an investigation of the stream/aquifer relationships in the Republican River Basin located in southwest Nebraska. Ground and surface water was analyzed for tritium, deuterium, 18O, and major ions. Temperature, pH, conductivity and alkalinity were determined on-site. Samples were collected during 1997 and 1998 from irrigation wells throughout the entire basin. Localized interactions between groundwater and surface water were examined during twenty-four hour pump tests performed on the irrigation wells screened in the alluvium along the river valley and its tributaries. These data show there are differences between the ground and surface waters …
The Effect Of Divalent Cations On The Prophenoloxidase Enzyme Cascade Activity In The Freshwater Crayfish Cambarus Latimanus, Hans Skailand Eikaas
The Effect Of Divalent Cations On The Prophenoloxidase Enzyme Cascade Activity In The Freshwater Crayfish Cambarus Latimanus, Hans Skailand Eikaas
Theses and Dissertations
The effect of divalent cations such as cadmium, calcium, copper, lead and magnesium upon the prophenoloxidase system (proPO) was studied in hemocytes of the crayfish Cambarus latimanus. It was demonstrated that cadmium, calcium, copper and lead increased proPO activity significantly, whereas magnesium had no statistically significant effect on the system. Also, the molecular weight of the proPO enzyme was estimated using SDS-PAGE and found to be approximately 76 kDa.
Earth News, Fall 1999, Department Of Earth Science, University Of Northern Iowa.
Earth News, Fall 1999, Department Of Earth Science, University Of Northern Iowa.
Earth News
Inside this issue:
--- Earth Science Staff Activities
--- Faculty Research, Publications, and Recognition
--- Profile: Wayne Anderson
--- PRISMS Helps Physic Students "See"
--- UNI Meteorology Students "Chase" Tornadoes in Des Moines
--- Technology Takes classes, teachers into the Next Millenium
--- Gifts to the Department of Earth Science
--- Volcanology Students Study Volcanoes in Italy, Sicily and the Aeolian Islands
--- Spring Trip 2000
--- Gifts to the Department of Earth Science
--- 1999-2000 Scholarship and Award Recipients
--- Earth Science Seminar Series
--- 1999 Earth Science Graduates
--- Student Research Presentations
--- Earth Science Majors
--- Alumni …
The Effects Of Phosphorus Enrichment On The Dominant Phytoplankton Communities Of Chaney Lake, Kathy Tehrani
The Effects Of Phosphorus Enrichment On The Dominant Phytoplankton Communities Of Chaney Lake, Kathy Tehrani
Masters Theses & Specialist Projects
Chaney Lake is a temporary karst wetland located in southern Warren County, Kentucky. Because of an impermeable chert layer between the surface and the porous limestone, Chaney Lake fills with water over the winter and spring and then gradually drains over the summer. Three experiments were conducted over the course of the 1998 flooding season to assess the effects of phosphorus addition on the phytoplankton community in Chaney Lake. Ten plastic-sided mesocosms were constructed and placed in the marsh area of the wetland at three different periods: early spring, early summer, and late summer. Phosphorus in the form of K2HPO4 …
Morphology Of Wetland Streams, Michael C. Jurmu
Morphology Of Wetland Streams, Michael C. Jurmu
All-Inclusive List of Electronic Theses and Dissertations
Recent understanding and concern with wetland environments has resulted in an increase in restoration and creation projects aimed at replicating these ecosystems. The unique characteristics within wetland environments result in different controls on streams traversing these areas, yet little research has been conducted to determine whether the morphology of these streams differs from streams in non-wetland, alluvial environments. Wetland streams from three different physiographic regions of the U.S. are compared to four morphological models and 12 additional features cited as typical in non-wetland streams. Analysis of this comparison will aid in determining whether wetland streams have differing morphology and which …
Maritime Pine For Western Australia - Revegetation On Farms Information Kit, David Bicknell, Department Of Conservation And Land Management
Maritime Pine For Western Australia - Revegetation On Farms Information Kit, David Bicknell, Department Of Conservation And Land Management
Natural resources published reports
Revegetation on farms
The Revegetation on Farms Project and the material in this Information Kit is targeted at the agricultural zone of Western Australia with less than 600 mm rainfall. Some of the information is valid outside this range.
All information is provided in good faith, to help make informed revegetation decisions leading to sustainable land use.
TreeNote No 20 - Weed control in eucalypts and pines
TreeNote No 21 - Insect pests of eucalypts and pines
In search of the perfect pine - David Gough (Article)
Farming carbon - Syd Shea (Article)
Modeling Macrophytes Of The Columbia Slough, Oregon, Chris Berger, Scott A. Wells
Modeling Macrophytes Of The Columbia Slough, Oregon, Chris Berger, Scott A. Wells
Civil and Environmental Engineering Faculty Publications and Presentations
The Columbia Slough is a tidally influenced freshwater system of wetlands, channels, and lakes located within the Portland, Oregon metropolitan area at the confluence of the Willamette and Columbia Rivers. It is a eutrophic water body susceptible to algae blooms and crashes and periods of high pH which violate water quality standards. High nutrient loads from groundwater principally controls algae productivity. Past structural changes to the Columbia Slough have included filling of wetlands and lakes and the construction of levees, dikes, culverts and irrigation channels. These changes have altered the natural flow dynamics creating an environment more conducive to eutrophication. …
Liming Of Vineyard Soils, Thomas J. Rice
Liming Of Vineyard Soils, Thomas J. Rice
Earth and Soil Sciences
Liming vineyard soils to increase soil pH and raise calcium levels has been practiced for centuries in the humid areas of the world where soils tend to be more acid. Today, liming is increasingly practiced in the semiarid central coast regions of California, where liming of vineyards was unheard of even a decade ago.
Past agricultural practices, such as the addition of sulfur, acid-forming nitrogen fertilizers, and organic soil amendments, have caused soil acidification. Previously, most of these lands were either open space, range lands, or planted to grain crops.
To avoid unnecessary expense and protect the soil from environmental …
Bulletin 4369 - Ord River Irrigation Area - Kununurra Western Australia, Agriculture Western Australia
Bulletin 4369 - Ord River Irrigation Area - Kununurra Western Australia, Agriculture Western Australia
Bulletins 4000 -
The Ord River Irrigation Area (ORIA) in the Kimberley Province of Western Australia is the product of a bold and imaginative plan to develop part of the nation's tropical north for intensive agriculture by harnessing the waters of the Ord River. The principal features of the scheme are:
* A major storage reservoir formed by a dam constructed where the Ord River enters the Carr-Boyd Ranges, 160 kilometres south-east of Wyndham.
* A diversion dam, 50 kilometres further downstream, to raise the river level and divert water to be released from the major storage reservoir onto the irrigable lands.
* …
Zinc Speculation And Ligand Fluxes In Chesapeake Bay And Elizabeth River Pore Waters, Duncan Glover Byers
Zinc Speculation And Ligand Fluxes In Chesapeake Bay And Elizabeth River Pore Waters, Duncan Glover Byers
Chemistry & Biochemistry Theses & Dissertations
Presented here are the first data on the vertical concentrations, complexation, speciation, and fluxes of total dissolved zinc and zinc complexing ligands, and zinc speciation in sediment pore waters in the Chesapeake Bay and Elizabeth River, Virginia.
Sediment pore waters were collected in mid and southern Chesapeake Bay in November 1997 and in the Elizabeth River (Pinner's Point) in March, April, and July 1998. Flux experiments were conducted in Elizabeth River sediment cores in April and July 1998. [TDZn] and zinc complexation were determined using differential pulse anodic stripping voltammetry at a hanging mercury drop electrode (DPASV-HMDE).
[TDZn] in the …
Molybdenum Accumulation In Cariaco Basin Sediment Over The Past 24 K.Y.: A Record Of Water-Column Anoxia And Climate, Walter E. Dean, David Z. Piper, Larry C. Peterson
Molybdenum Accumulation In Cariaco Basin Sediment Over The Past 24 K.Y.: A Record Of Water-Column Anoxia And Climate, Walter E. Dean, David Z. Piper, Larry C. Peterson
United States Geological Survey: Staff Publications
Molybdenum (Mo) concentrations in a sediment core from the Cariaco basin on the Venezuelan continental shelf can be partitioned between a marine fraction and a terrigenous fraction. The accumulation rate of the marine fraction of Mo increased abruptly 15 000 calendar years ago (15 ka), from <0.5 mg • cm-2 • yr-1 to >4 μg • cm-2 • yr-1, and then decreased abruptly at 9 ka. The accumulation rate remained high throughout this 6 k.y. period, but exhibited maxima at 15–14 and 12.5 ka, corresponding in time to meltwater pulse IA into the Gulf of Mexico and the onset …0.5>
A Comprehensive Approach For Evaluation Of Groundwater Vulnerability To Contamination, Shafiul H. Chowdhury
A Comprehensive Approach For Evaluation Of Groundwater Vulnerability To Contamination, Shafiul H. Chowdhury
Dissertations
Groundwater vulnerability to contamination from surface sources was evaluated for Nottawa Creek Watershed, Calhoun County Michigan using AQUIPRO and DRASTIC vulnerability methods. A geographic information system (GIS) was used to analyze and map the data. Forty groundwater samples were collected following a statistical sampling protocol from private wells. Samples were analyzed for nitrate-N and atrazine. Atrazine was not detected (detection limit 0.1 ppb) in any of the samples. Five samples contained detectable nitrate-N (detection limit 0.05 mg/L). Due to insufficient chemical data, the relative AQUIPRO and DRASTIC vulnerability scores could not be compared with the frequency of occurrences o f …
Close-Range And Satellite Remote Sensing Of Algal Biomass In The Iowa Great Lakes, Eric A. Wilson
Close-Range And Satellite Remote Sensing Of Algal Biomass In The Iowa Great Lakes, Eric A. Wilson
Department of Geography: Dissertations, Theses, and Student Research
The utility of both close-range and satellite remote sensing for assessing inland water quality was examined in the Iowa Great Lakes. The water quality of this system is of considerable interest because of its status as an environmental, recreational, and therefore, economic resource. The broad range of optical conditions present in the lakes and the wealth of literature on the system make it an ideal environment for water quality remote sensing research. The goal of this research was to survey the water quality of the Iowa Great Lakes via remote sensing, evaluate different predictive algorithms, and map the distribution of …
Molecular Characterization Of Soil Ammonia-Oxidizing Bacteria Based On The Genes Encoding Ammonia Monooxygenase, Jose Javier Alzerreca
Molecular Characterization Of Soil Ammonia-Oxidizing Bacteria Based On The Genes Encoding Ammonia Monooxygenase, Jose Javier Alzerreca
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Ammonia-oxidizing bacteria (AOB) are chemolithotrophs that oxidize ammonia/ammonium to nitrite in a two-step process to obtain energy for survival. AOB are difficult to isolate from the environment and iso lated strains may not represent the diversity in soil. A genetic database and molecular tools were developed based on the ammonia monooxygenase (AMO) encoding genes that can be used to assess the diversity of AOB that exist in soil and aquatic environments without the isolation of pure cultures. The amo genes have excellent potential as molecular markers; since AMO is only found in the AOB and is essential for their metabolism, …
Evaluating Snowmelt Runoff, Infiltration, And Erosion In A Sagebrush-Steppe Ecosystem, Eric K. Duffin
Evaluating Snowmelt Runoff, Infiltration, And Erosion In A Sagebrush-Steppe Ecosystem, Eric K. Duffin
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Production of low-level radioactive waste (LLRW) has created a need for safe storage facilities. These facilities must be capable of isolating radioactive waste and preventing contamination from physical or biological intrusion until the waste material is isotopically stable. At the present time, managers of the Idaho National Engineering and Environmental Laboratory (INEEL) have a substantial database characterizing rainfall events and the subsequent impact on integrity of shallow land burial sites used for storage of LLRW. Little information has been gathered describing the processes of snow accumulation/ablation and the resulting impact on storage facilities. This study examines snowmelt runoff, infiltration, and …
Tectonic Forcings Of Maastrichtian Ocean-Climate Evolution, Tracy D. Frank, Michael A. Arthur
Tectonic Forcings Of Maastrichtian Ocean-Climate Evolution, Tracy D. Frank, Michael A. Arthur
Department of Earth and Atmospheric Sciences: Faculty Publications
A global compilation of deep-sea isotopic records suggests that Maastrichtian ocean-climate evolution was tectonically driven. During the early Maastrichtian the Atlantic intermediate-deep ocean was isolated from the Pacific, Indian, and Southern Oceans; deep water formed in the high-latitude North Atlantic and North Pacific. At the early/late Maastrichtian boundary a major reorganization of oceanic circulation patterns occurred, resulting in the development of a thermohaline circulation system similar to that of the modem oceans. A combination of isotopic and plate kinematic data suggests that this event was triggered by the final breaching of tectonic sills in the South Atlantic and the initiation …
Effects Of Organic Matter And Iron-Rich Clay On Mobility Of Trace Metals From Flue Dust Contaminated Soil, Scott Ephraim Lewis
Effects Of Organic Matter And Iron-Rich Clay On Mobility Of Trace Metals From Flue Dust Contaminated Soil, Scott Ephraim Lewis
OES Theses and Dissertations
The enhanced leaching of trace metals through soil becomes a concern for human health if dissolved trace metals reach groundwater and migrate into a public water system. A serial batch extraction procedure was implemented to determine the effects of Vitagrow © organic matter and Fe-Rich TM clay on the mobility of trace metals (Zn, Pb, and Cd) from a flue dust treated (0, 600, 1200, and 2400 μgig Zn) Appling soil.
The addition of an organic matter (OM) amendment to the Appling soil enhanced Pb mobility and reduced soluble Zn and Cd. In general, average solution concentrations of trace metals …
Classification Of Great Basin Plant Communities Occurring On Dugway Proving Ground, Utah, Vel Emrick, Alison Hill
Classification Of Great Basin Plant Communities Occurring On Dugway Proving Ground, Utah, Vel Emrick, Alison Hill
All U.S. Government Documents (Utah Regional Depository)
No abstract provided.
Long-Term Prairie Falcon Population Changes In Relation To Prey Abundance, Weather, Land Uses, And Habitat Conditions, Karen Steenhof, Michael Kochert, Leslie B. Carpenter, Robert N. Lehman
Long-Term Prairie Falcon Population Changes In Relation To Prey Abundance, Weather, Land Uses, And Habitat Conditions, Karen Steenhof, Michael Kochert, Leslie B. Carpenter, Robert N. Lehman
United States Geological Survey: Staff Publications
We studied a nesting population of Prairie Falcons (Falco mexicanus) in the Snake River Birds of Prey National Conservation Area (NCA) from 1974-1997 to identify factors that influence abundance and reproduction. Our sampling period included two major droughts and associated crashes in Townsend's ground squirrel (Spermophilus townsendii) populations. The number of Prairie Falcon pairs found on long-term survey segments declined significantly from 1976-1997. Early declines were most severe at the eastern end of the NCA, where fires and agriculture have changed native shrubsteppe habitat. More recent declines occurred in the portion of canyon near the Orchard …
A Case For Site Acclimation In The Reintroduction Of The Endangered Razorback Sucker (Xyrauchen Texanus), United States Geological Survey
A Case For Site Acclimation In The Reintroduction Of The Endangered Razorback Sucker (Xyrauchen Texanus), United States Geological Survey
All U.S. Government Documents (Utah Regional Depository)
Two site-acclimation studies (Mueller and Marsh 1998, Foster and Mueller 1999) were conducted in 1997 and 1998. The primary emphasis was habitat use and dispersal but we also examined if the rapid dispersal, typically associated with hatchery-produced razorback suckers (suckers), could be mitigated by allowing fish a period of time to recover from stocking-induced stress. Findings of those studies and existing physiological literature suggest that current stocking protocols may subject stocked fish to unnecessary behavioral or physiological stress that could impact performance and ultimately survival. This report presents those findings and recommends an evaluation of existing stocking procedures for the …
Description Of The Pelagic Zooplankton And Fish Communities Of Lakes Powell And Mead, United States Geological Survey
Description Of The Pelagic Zooplankton And Fish Communities Of Lakes Powell And Mead, United States Geological Survey
All U.S. Government Documents (Utah Regional Depository)
Fishery biologists from Arizona, Nevada, and Utah have been faced with the imposing dilemma of monitoring the pelagic fishery of Lakes Powell and Mead. Standard sampling procedures typically used to monitor shoreline fisheries are simply inadequate for the deep volumes of pelagic habitat found in these two reservoirs. Nearly a decade ago, Arizona and Nevada biologists recommended that hydroacoustics be used to monitor these communities (Persons and Dreyer 1987a,b, NDOW 1994). However, for various reasons an acoustical monitoring program was never fully implemented. This study represents the first attempt to describe the pelagic fishery of either reservoir using acoustic technology.
Classification Of Explosives Transformation Products In Plant Tissue, Steven L. Larson, Robert P. Jones, Lynn Escalon, Don Parker
Classification Of Explosives Transformation Products In Plant Tissue, Steven L. Larson, Robert P. Jones, Lynn Escalon, Don Parker
United States Army Corps of Engineers, Omaha District
Explosives contamination in surface or groundwater used for the irrigation of food crops and phytoremediation of explosives-contaminated soil or water using plant-assisted biodegradation have brought about concerns as to the fate of explosives in plants. Liquid scintillation counting, high-performance liquid chromatography, and gel permeation chromatography were utilized to characterize explosives (hexahydro-1,3,5-trinitro-1,3,5-triazine and trinitrotoluene) and their metabolites in plant tissues obtained from three separate studies. Analyzing tissues of yellow nutsedge (Cyperus esculentus), corn (Zea mays), lettuce (Lacuta sativa), tomato (Lyopersicum esculentum), radish (Raphanus sativus), and parrot feather (Myriophyllum aquaticum) …
Areas Susceptible To Irrigation-Induced Selenium Contamination Of Water And Biota In The Western United States, Ralph L. Seiler, Joseph P. Skorupa, Lorri A. Peltz
Areas Susceptible To Irrigation-Induced Selenium Contamination Of Water And Biota In The Western United States, Ralph L. Seiler, Joseph P. Skorupa, Lorri A. Peltz
United States Geological Survey: Publications
The U.S. Department of the Interior (DOI) studied contamination induced by irrigation drainage in 26 areas of the Western United States during 1986–95. Comprehensive compilation, synthesis, and evaluation of the data resulting from these studies were initiated by DOI in 1992. Soils and ground water in irrigated areas of the West can contain high concentrations of selenium because of (1) residual selenium from the soil’s parent rock beneath irrigated land; (2) selenium derived from rocks in mountains upland from irrigated land by erosion and transport along local drainages, and (3) selenium brought into the area in surface water imported for …
Predation Of Artificial Ground Nests On White-Tailed Prairie Dog Colonies, Bruce W. Baker, Thomas R. Stanley, James A. Sedgwick
Predation Of Artificial Ground Nests On White-Tailed Prairie Dog Colonies, Bruce W. Baker, Thomas R. Stanley, James A. Sedgwick
United States Geological Survey: Staff Publications
Prairie dog (Cynomys spp.) colonies are unique to prairie and shrub-steppe landscapes. However, widespread eradication, habitat loss, and sylvatic plague (Yersinia pestis) have reduced their numbers by 98% since historical times. Birds associated with prairie dogs also are declining. Potential nest predators, such as coyotes (Canis latrans), swift foxes (Vulpes velox), and badgers (Taxidea taxus), may be attracted to colonies where a high concentration of prairie dogs serve as available prey. Increased abundance of small mammals, including prairie dogs, also may increase the risk of predation for birds nesting on colonies. …
Trace-Element Concentrations In Streambed Sediment Across The Conterminous United States, Karen Rice
Trace-Element Concentrations In Streambed Sediment Across The Conterminous United States, Karen Rice
United States Geological Survey: Staff Publications
Trace-element concentrations in 541 streambed-sediment samples collected from 20 study areas across the conterminous United States were examined as part of the National Water-Quality Assessment Program of the U.S. Geological Survey. Sediment samples were sieved and the <63-μm fraction was retained for determination of total concentrations of trace elements. Aluminum, iron, titanium, and organic carbon were weakly or not at all correlated with the nine trace elements examined: arsenic, cadmium, chromium, copper, lead, mercury, nickel, selenium, and zinc. Four different methods of accounting for background/ baseline concentrations were examined; however, normalization was not required because field sieving removed most of the background differences between samples. The sum of concentrations of trace elements characteristic of urban settings-copper, mercury, lead, and zinc-was well correlated with population density, nationwide. Median concentrations of seven trace elements (all nine examined except arsenic and selenium) were enriched in samples collected from urban settings relative to agricultural or forested settings. Forty-nine percent of the sites sampled in urban settings had concentrations of one or more trace elements that exceeded levels at which adverse biological effects could occur in aquatic biota.
A Biogeochemical Comparison Of Fossil (Carboniferous) And Modern Crustose Red Algae, Michael A. Kruge, John E. Utgaard, William Ferry
A Biogeochemical Comparison Of Fossil (Carboniferous) And Modern Crustose Red Algae, Michael A. Kruge, John E. Utgaard, William Ferry
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
The nature of the contribution of the various types of algae to sedimentary organic matter continues to be a topic of research interest. Crustose red algae have however received less attention than other types. The fossil calcareous red algae (Rhodophyta) analyzed in this study are two relatively unrecrystallized specimens of Parachaetetes (Family Solenoporacea) from the lower part of the Ste. Genevieve Formation (Carboniferous, Visean) in Union County, Illinois, USA. They occurred in the patch reef phase of a small carbonate mudmound-patchreef. The three modern specimens (collected and identified by F. Collier) are the crustose algae Lithothamnion, Clathromorphum and Phymatolithon …
Chemistry Of Maceral And Groundmass Density Fractions Of Torbanite And Cannel Coal, Zhiwen Han, Michael A. Kruge
Chemistry Of Maceral And Groundmass Density Fractions Of Torbanite And Cannel Coal, Zhiwen Han, Michael A. Kruge
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
Microscopically, torbanite and cannel coal are composed of coarser macerals set in a fine-grained to amorphous groundmass. It is often assumed that the amorphous groundmass is genetically related to the distinct macerals. The separation of macerals and groundmass from 14 late Paleozoic torbanite, cannel, and humic coals permits the analysis of individual constituents using elemental analysis and flash pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Cluster and principal component analyses of the Py-GC/MS data further reveal the chemical similarities and differences between the various constituents. Pyrolyzates of Botryococcus-related alginites are characterized by an abundance of normal alkadienes, alkenes, and alkanes. Even their …
Ground-Water Quality In Kentucky: Nitrate-Nitrogen, Philip G. Conrad, Daniel I. Carey, James S. Webb, James S. Dinger, Matthew J. Mccourt
Ground-Water Quality In Kentucky: Nitrate-Nitrogen, Philip G. Conrad, Daniel I. Carey, James S. Webb, James S. Dinger, Matthew J. Mccourt
Information Circular--KGS
No abstract provided.