marine sediment Articles
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Proposal for a deconvolution procedure for the gas chromatographic estimation of pristane and phytane in marine sediments
In this paper, a deconvolution procedure for improving the quantitative estimation of specific hydrocarbons by chromatographic techniques is reported. The proposed technique has been applied to the gas chromatographic determination of the pristane to phytane (pri/phy) ratio, an important parameter for the evaluation of biogenic and anthropogenic contributions present in the hydrocarbon content of ...
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Marine sediment components: identification and dispersal assessed by diffuse reflectance spectrophotometry
Analysis of deep-sea sediments presents a number of exceptional challenges. Generally, the amount of material available is small and has to be shared among investigators. Also, deep-sea sediment contains a diverse range of components from a variety of sources including lithogenous, biogenous and hydrogenous. Finally, large number of samples is frequently analysed making rapid analysis a ...
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Sorption kinetics of TNT and RDX in anaerobic freshwater and marine sediments: Batch studies
Examining the partitioning of explosives onto sediment in marine environments is critical to predict the toxicological impacts of worldwide explosive‐contaminated sites adjacent to estuaries, wetlands, and the coastal ocean. Marine sediments have been identified as sites of enhanced munitions removal, yet most studies addressing these interactions focus on soils and freshwater sediments. This ...
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Speciation of butyltin compounds in marine sediments and sea-shells by HG/GC/QFAAS
After optimisation of sample pretreatment and determination procedures, butyltin compounds were determined in selected marine sediments and biota using the hydride generation/gas chromatography/quartz furnace atomic absorption spectrometry method. Butyltins were detected in all surface sediment samples of Arcachon Bay, though at widely different concentrations (from a few ng g-1 in remote areas ...
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Emulsifying and metal ion binding activity of a glycoprotein exopolymer produced by pseudoalteromonas sp. Strain TG12
In this study, we describe the isolation and characterization of a new exopolymer that exhibits high emulsifying activities against a range of oil substrates and demonstrates a differential capacity to desorb various mono-, di-, and trivalent metal species from marine sediment under nonionic and seawater ionic-strength conditions. This polymer, PE12, was produced by a new isolate, ...
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CL#5 - In Situ BioLogix Application - Case Study
Site Information A site in southern Alberta was polluted by dry cleaning solvents. The solvent entered the soil below the dry cleaning building and percolated through the soil to a perched ground water zone and an underlying second ground water zone. The soil and sediments are interbedded alluvial and marine sediments with a high permeability. The site was close to a water course, and ...
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Aeolian dust in sediment: a re-examination of methods for identification and dispersal assessed by diffuse reflectance spectrophotometry
Analyses of aeolian sediments present two main challenges: (1) when aerosol particles are collected on atmospheric filters, only a small amount of aeolian material is normally present, and (2) in these and other samples, the aeolian sediment is typically mixed with other types of particles and the aeolian material often makes up only a small percentage of the total sample. Diffuse Reflectance ...
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Use of a novel sediment exposure to determine the effects of triclosan on estuarine benthic communities
Triclosan (5‐chloro‐2‐[2,4‐dichlorophenoxy]phenol) is a relatively new, commonly used antimicrobial compound found in many personal care products. Triclosan is toxic to marine organisms at the micrograms per liter level, can photodegrade to a dioxin, can accumulate in humans, and has been found to be stable in marine sediments for over 30 years. To determine the effects of triclosan on marine ...
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Fourier transform infrared spectroscopic investigation of humic substance samples of different origin and typology supported by chemometric tools
In this paper 198 FTIR spectra of humic substance (HS) extracted from lake, marine sediments, soils and by Antarctic seawater were examined by Principal Component Analysis (PCA), Independent Component Analysis (ICA) and Two-dimensional Mapping (2DMAP) to identify the compositional and structural characteristics which characterise the typologies of samples examined and which are hardly detectable ...
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Adsorption of tetracyclines on marine sediment during organic matter diagenesis
The effect of decomposition and diagenesis of sediment organic matter (SOM) on the adsorption of emerging pollutants by the sediment has been seldom addressed. In the present experimental study, artificial sediment was incubated to simulate the natural organic diagenesis process and hence investigate the influence of organic diagenesis on the adsorption of tetracyclines (TCs) by marine ...
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Establishment of a radioactive contamination index in seawater from the Gulf and Pacific coasts in Mexico
This paper intends to establish one radioactive contamination index in seawater based on the relation A1/A2, where A1 is the radioactivity due to the contaminant radioisotope 137Cs and A2 is the radioactivity due to the natural radioisotope 40K, both expressed either as Bq/l in seawater or Bq/g in sea salt. At a second step, the same volumes of marine sediments were detected, but in this case ...
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Assessing bioavailability of DDT and metabolites in marine sediments using solid phase microextraction with performance reference compounds
Solid phase microextraction (SPME) has often been used to estimate the freely dissolved concentration (Cfree) of organic contaminants in sediments. A significant limitation in the application of SPME for Cfree measurement is the requirement for attaining equilibrium partition that is often difficult for strongly hydrophobic compounds such as DDT. A method was developed using SPME with stable ...
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Attenuation of TNT in seawater microcosms
The ability of two differing marine sediments (one clayey, the other sandy) to attenuate the explosive 2,4,6-trinitrotoluene (TNT), dissolved in intertidal seawater from the eastern English coast of the North Sea, was examined using aerobic microcosms. Analysis of the seawater from the microcosms revealed an initial sharp decline in TNT concentration with clayey sediment in both sterilized (to ...
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In Situ Soil and Ground Water Bioremediation Using CL-Out Cometabolism for PCE and TCE Removal - Case Study
Background The dry cleaning solvent was found in an area around a dry cleaning machine. The solvent entered the soil below the building and percolated through the soil to a perched ground water zone and an underlying second ground water zone. The soil and sediments are interbedded alluvial and marine sediments with a high permeability. The site was close to the beach, and ground water is ...
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Characterizing the effects of bisphenol A on sediment dwelling benthic organisms
Bisphenol A (BPA) is a high production volume chemical intermediate used primarily in the production of polycarbonate plastics and epoxy resins. It primarily enters surface water and sediment via effluent discharges during its manufacture and use. The physical properties of BPA suggest that sediment is a potential sink and may result in exposure to benthic organisms. Currently there are no ...
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Characteristics, distribution and sources of polychlorinated biphenyls (PCBs) in coastal sediments from the heavily industrialized area of Asalouyeh, Iran
In this research, the levels of polychlorinated biphenyls (PCBs) were investigated in the marine sediments of Asaluyeh harbor, in the Persian Gulf. The samples were taken from industrial, semi-industrial and urban regions. The mean concentration levels of total (Σ) 18 detected PCBs were 514.32, 144.67 and 31.6 pg/g dw for the industrial, semi-industrial and urban sampling stations, ...
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Sorption of Cr, Pb, Cu, Zn, Cd, Ni, and Co to nano-TiO2 in seawater
In this study, the role of nanoparticles in complex aqueous matrices such as the Baltic Sea was investigated in batch-mode experiments in which titanium dioxide nanoparticles (nano-TiO2) were tested for their ability to remove heavy metals (Cr, Pb, Cu, Zn, Cd, Ni, Co) from multicomponent spiked and non-spiked Baltic Sea water. The experimental data were analyzed using different isotherms ...
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Mapping top of rock and sediment thickness case study
San Felipe, Panama A port expansion was planned off the coast of San Felipe, Panama. GeoView was tasked to provide bathymetric information within the survey area, map the top of rock and evaluate the thickness of the overlying marine sediments. The survey area was approximately 300 hectares in size. GeoView collected sub-bottom profiling and bathymetry data along transect lines spaced ...
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Isotopic exchange on SPME fiber in sediment under stagnant conditions: Implications for field application of PRC calibration
An overlooked issue for field application of in situ performance reference compound (PRC) calibration methods is the validity of the assumption that both the sorption of a target compound and desorption of its corresponding PRC follow the first‐order kinetics with the same rate constants under stagnant conditions. In the present study, disposable polydimethylsiloxane fibers of two sizes (7‐ ...
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Distribution and accumulation of heavy metals in surface sediments from a subtropical bay affected by the Special Economic Zone, China
The concentrations of nine metals (Cd, Cr, Cu, Ni, Mn, Pb, Zn, Fe, and Al) in surface sediments from 14 sampling sites in Shantou Bay were determined in order to understand current metal levels and spatial distribution due to the rapid development of the Shantou Special Economic Zone. Results showed that metal concentrations in surface sediments varied from 0.31 to 1.74 mg kg–1 for Cd, ...
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