scholarly journals The Fate of Diesel Fuel Spilled by the Bahia Paraiso in Arthur Harbor, Antarctica

1991 ◽  
Vol 1991 (1) ◽  
pp. 493-500
Author(s):  
Mahlon C. Kennicutt ◽  
Stephen T. Sweet ◽  
William R. Fraser ◽  
Mary Culver ◽  
William L. Stockton
Keyword(s):  
Aromatic Hydrocarbons ◽  
Diesel Fuel ◽  
Dry Weight ◽  
High Energy ◽  
Polynuclear Aromatic Hydrocarbons ◽  
Microbial Oxidation ◽  
Energy Environment ◽  
Minor Portion ◽  
One Year ◽  
A Minor

ABSTRACT The Bahia Paraiso spilled an estimated 600,000 liters of refined product (diesel fuel arctic, DFA) into Arthur Harbor, Antarctica, in January 1989. Water, organisms, and sediments within a two-mile radius of the wreck were contaminated to various degrees for at least one year after the spill. The DFA contained about one percent toxic aromatic hydrocarbons, including naphthalenes, fluorenes, and phenanthrenes. Intertidal areas were most directly affected, but all components of the harbor ecosystem were contaminated during the first few weeks of the spill. DFA was detected in tissues from birds, limpets, macroalgae, clams, and bottom feeding fish as well as water and sediments collected over a six-week period. During the most intense phase of the spill, total polynuclear aromatic hydrocarbons reached levels as high as 125,147 and 1,723 ppb (dry weight) in limpet tissues and sediments, respectively. The high-energy environment, the relatively small volume of material released, and the volatility of the refined product helped to limit toxic effects over time and space. Most of the spilled material evaporated, and the rest was diluted and swept from the area by winds and currents. Sedimentation, biological uptake, microbial oxidation, and photo-oxidation accounted for removal of only a minor portion of the spill.

Changes in the herbaceous and vine communities at the Bisley Experimental Watersheds, Puerto Rico, following Hurricane Hugo

1999 ◽  
Vol 29 (9) ◽  
pp. 1433-1437 ◽  
Author(s):  
Jesus D Chinea
Keyword(s):  
Puerto Rico ◽  
Permanent Plots ◽  
Closed Forest ◽  
Minor Portion ◽  
Abundance And Diversity ◽  
Tree Component ◽  
One Year ◽  
A Minor ◽  
Hurricane Hugo ◽  
Experimental Watersheds

While herbaceous species and vines constitute a minor portion of the biomass in tropical closed forest ecosystems, they account for a substantial portion of the diversity of these ecosystems and become more conspicuous after natural disturbances. This study describes the changes in abundance and diversity of the herbs and vines during 5 years following Hurricane Hugo at the Bisley Experimental Watersheds, Puerto Rico. The cover of herbs, ferns, and vine species was sampled within a 5-m2 area in 25 randomly chosen circular permanent plots within the 13 ha of these watersheds. Sampling was done 12, 18, 36, 48, and 60 months after the hurricane. One year after the hurricane the overall mean herbaceous cover in the watersheds was 55%. Four years later, the cover and species richness of herbs and vines, but not ferns, had been significantly reduced. The only change in species diversity (H') was a significant increase in ferns. These changes are explained in terms of the extent and spatial variability of the hurricane damage, as well as changes in the tree component of this ecosystem.

A THREE-YEAR BASELINE SAMPLING AND ANALYSIS STUDY OF PETROLEUM POLLUTANTS IN COASTAL LOUISIANA

2005 ◽  
Vol 2005 (1) ◽  
pp. 201-206 ◽  
Author(s):  
David Gisclair ◽  
Javed Iqbal
Keyword(s):  
Oil Spill ◽  
Aromatic Hydrocarbons ◽  
Mississippi River ◽  
Oil Spills ◽  
Biological Effects ◽  
Dry Weight ◽  
Average Concentration ◽  
Polynuclear Aromatic Hydrocarbons ◽  
The Mean ◽  
Coastal Louisiana

ABSTRACT The Louisiana Oil Spill Coordinator's Office (LOSCO) conducted a three-year study of baseline levels of oil spill constituents in South Louisiana as mandated by Act 740 of the Louisiana Legislature. The act mandated an environmental inventory concentrating on areas with a high probability of oil spills. The main goal of the project was to streamline restoration efforts in Coastal Louisiana, the Mississippi River, major tributaries and reduce associated risks to habitat. The study consisted of 3,540 composite sediment samples collected at 1,180 sites each year from 1997 through 1999. Results indicate that the mean level of total unresolved petroleum hydrocarbons (TUPH) in coastal Louisiana and major rivers during 1997 to 1999 was 44,608ng/g based on dry weight sediment. The mean total saturated hydrocarbons n-alkanes level (nC9-nC35) was 5,444ng/g. and mean total polynuclear aromatic hydrocarbons (PAH) level was 587ng/g. Results indicate chronic/degraded and recent input of petroleum contamination in coastal areas and the Mississippi river. These results indicated that petroleum constituents in Louisiana sediments are bio-available reservoirs of polynuclear aromatic hydrocarbons posing some risk to the ecosystem. Approximately 5% of the sites investigated have TPAH levels more than 1,000ng/g in three consecutive years while 51% of the samples have TPAH levels less than 100ng/g indicating low pollution. More than 98% of the samples were below NOAA sediments quality guidelines ERL (Effects Range – Low) values for PAHs. About 159 hot spots in 17 parishes (counties) were identified where all TUPH, TPAH and T-Sat exceeded the average concentration in at least one sampling year. The data suggests that current concentrations of contaminants in Louisiana are basically not in the toxic range to produce biological effects. However efforts would be necessary to monitor, control, and alleviate contaminants of concern especially in hotspot areas.

scholarly journals Chemical Studies on Tobacco Smoke. XIII. Inhibition of the Pyrosyntheses of Several Selective Smoke Constituents

1970 ◽  
Vol 5 (6) ◽  
Author(s):  
G. Rathkamp ◽  
D. Hoffmann
Keyword(s):  
Organic Compounds ◽  
Aromatic Hydrocarbons ◽  
Tobacco Smoke ◽  
Selective Reduction ◽  
Tobacco Product ◽  
Polynuclear Aromatic Hydrocarbons ◽  
Nitrate Content ◽  
Minor Degree ◽  
Chemical Studies ◽  
A Minor

AbstractEarlier studies demonstrated that polynuclear aromatic hydrocarbons (PAH) are selectively reduced in the smoke of alkali nitrate rich tobaccos. We hypothesized, therefore, that in the burning cone of a tobacco product, the non-volatilized organic compounds are partially pyrolyzed to C,H-radicals that may combine with each other and form, among others, the thermodynamically favoured PAH. Since we have in the burning cone of nitrate rich tobaccos an excess of thermically activated nitrogen oxides, we assumed that these may react as scavengers for C,H-radicals and, with it, partially inhibit the PAH pyrosynthesis. The present study was designed to challenge our working hypothesis. For the experiments we employed cigarettes to which we had added various amounts of KNO3 (0, 2.5, 5.0, 7.0 and 8.0 %). As expected, the yields of nitromethane, nitroethane, and nitrobenzene in the smoke increased with the increased of nitrate in the tobacco and the yields of phenanthrene, benz[a]anthracene, and benz[a]pyrene decreased. The concentration of naphthalene was only to a minor degree reduced with the increase of nitrates in the tobacco. One explanation for this observation could be that naphthalenes are primarily formed from specific tobacco terpenes, as suggested in the literature. As was expected, the smoke yields of N-unsubstituted and N-alkylated indoles was relatively little affected by the increase in the nitrate content, since these agents are predominantly formed from tryptophan. It was our objective to contribute to the understanding of the pyrosynthesis of carcinogenic PAH and the selective reduction of PAH in the smoke of nitrate rich tobacco. With the increase of our knowledge in this area we may also find an explanation for the reduced tumorigenicity of condensates from nitrate rich tobaccos

Multi-alkylated Polynuclear Aromatic Hydrocarbons of Tobacco Smoke: Separation and Identification

1978 ◽  
Vol 9 (4) ◽  
Author(s):  
M. E. Snook ◽  
R. F. Severson ◽  
R. F. Arrendale ◽  
H. C. Higman ◽  
O. T. Chortyk
Keyword(s):  
Liquid Chromatography ◽  
Cigarette Smoke ◽  
Aromatic Hydrocarbons ◽  
Ultra Violet ◽  
Polynuclear Aromatic Hydrocarbons ◽  
Gel Chromatography ◽  
Cigarette Smoke Condensate ◽  
Gas And Liquid Chromatography ◽  
Silicic Acid Chromatography ◽  
Derivatives Of

AbstractThe methyl, multi-methyl, and ethyl derivatives of the polynuclear aromatic hydrocarbons (PAH) of cigarette smoke condensate (CSC) were isolated from the neutrals by silicic acid chromatography, solvent partitioning and gel chromatography. The procedure yielded a relatively pure PAH isolate amenable to further identifications. The multi-alkylated PAH were concentrated in the early gel fractions with parent and higher ring PAH found in subsequent gel fractions. It was shown that CSC is very rich in alkylated PAH, and their successful identification required extensive use of gas and liquid chromatography and ultra-violet and GC - mass spectrometric techniques. High-pressure liquid chromatography (HPLC) separated individual isomers of the alkylated PAH in complex GC peaks. PAH from indene to pentamethylchrysene were found. This report concludes our identification studies on the PAH of CSC and complements our two previous reports in this journal. Collectively, our studies have identified approximately 1000 PAH of cigarette smoke condensate and have led to the development of methods for the routine quantitation of PAH in smalI quantities of cigarette smoke condensate.

Spectrophotometry Measurement of Polynuclear Aromatic Hydrocarbons in Hamilton Harbour Sediments

1991 ◽  
Vol 26 (1) ◽  
pp. 1-16 ◽  
Author(s):  
T.P. Murphy ◽  
H. Brouwer ◽  
M.E. Fox ◽  
E. Nagy
Keyword(s):  
Aromatic Hydrocarbons ◽  
Total Concentration ◽  
Coal Tar ◽  
Sediment Cores ◽  
Polynuclear Aromatic Hydrocarbons ◽  
Mass Spectrometry Analysis ◽  
Gas Chromatography Mass Spectrometry ◽  
Near Surface ◽  
Spectrometry Analysis ◽  
Hamilton Harbour

Abstract Eighty-one sediment cores were collected to determine the extent of coal tar contamination in a toxic area of Hamilton Harbour. Over 800 samples were analyzed by a UV spectrophotometric technique that was standardized with gas chromatography/mass spectrometry analysis. The coal tar distribution was variable. The highest concentrations were near the Stelco outfalls and the Hamilton-Wentworth combined sewer outfalls. The total concentration of the 16 polynuclear aromatic hydrocarbons (PAHs) in 48,300 m3 of near-surface sediments exceeded 200 µg/g.

Potential Contribution of Nutrients and Polycyclic Aromatic Hydrocarbons from the Creeks of Cootes Paradise Marsh

1996 ◽  
Vol 31 (3) ◽  
pp. 485-504 ◽  
Author(s):  
Patricia Chow-Fraser ◽  
Barb Crosbie ◽  
Douglas Bryant ◽  
Brian McCarry
Keyword(s):  
Aromatic Hydrocarbons ◽  
Laboratory Experiments ◽  
Dry Weight ◽  
Common Source ◽  
Potential Contribution ◽  
Nitrogen And Phosphorus ◽  
Engine Combustion ◽  
Polycyclic Aromatic ◽  
High Concentrations ◽  
Derivatives Of

Abstract During the summer of 1994, we compared the physical and nutrient characteristics of the three main tributaries of Cootes Paradise: Spencer, Chedoke and Borer’s creeks. On all sampling occasions, concentrations of CHL α and nutrients were always lowest in Borer’s Creek and highest in Chedoke Creek. There were generally 10-fold higher CHL α concentrations and 2 to 10 times higher levels of nitrogen and phosphorus in Chedoke Creek compared with Spencer Creek. Despite this, the light environment did not differ significantly between Spencer and Chedoke creeks because the low algal biomass in Spencer Creek was balanced by a relatively high loading of inorganic sediments from the watershed. Laboratory experiments indicated that sediments from Chedoke Creek released up to 10 µg/g of soluble phosphorus per gram (dry weight) of sediment, compared with only 2 µg/g from Spencer Creek. By contrast, sediment samples from Spencer Creek contained levels of polycyclic aromatic hydrocarbon that were as high as or higher than those from Chedoke Creek, and much higher than those found in Borer’s Creek. The distribution of normalized PAH concentrations suggests a common source of PAHs in all three tributaries, most likely automobile exhaust, since there were high concentrations of fluoranthene and pyrene, both of which are derivatives of engine combustion.

Polycyclic Aromatic Hydrocarbons (PAHs) in Sediments of the Brisbane River (Australia) – Preliminary Results

1989 ◽  
Vol 21 (2) ◽  
pp. 161-165 ◽  
Author(s):  
S. I. Kayal ◽  
D. W. Connell
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
River Estuary ◽  
Dry Weight ◽  
Weight Basis ◽  
Sediment Samples ◽  
Preliminary Results ◽  
Treated Sewage ◽  
Polycyclic Aromatic ◽  
Petroleum Refineries

Results of the analysis of twenty-three composite sediment samples revealed that PAHs are widely distributed in the Brisbane River estuary. Mean concentrations for individual compounds, on a dry weight basis, ranged from 0.03 µg/g for dibenz [ah] anthracene to 2.34 µg/g for fluoranthene. Observed PAH assemblages were rich in compounds having pyrolytic origins. However, the presence of petroleum derived compounds was indicative of the importance of petroleum as a PAH source in the estuary. Petroleum refineries, a coal loading terminal and a major treated sewage outfall located at the mouth were not indicated as major contributing sources of PAH pollution in the estuary.

Charge transfer energies of the complexes of (dibenzoylmethanato)boron difluoride with indeno-pyridines and polynuclear aromatic hydrocarbons

2013 ◽  
Vol 108 ◽  
pp. 181-185 ◽  
Author(s):  
Tandrima Chaudhuri ◽  
Sneha Salampuria ◽  
Pradip Kumar Tapaswi ◽  
Chhanda Mukhopadhyay ◽  
Subrata Chattopadhyay ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Aromatic Hydrocarbons ◽  
Polynuclear Aromatic Hydrocarbons ◽  
Boron Difluoride

scholarly journals In-Vitro Evaluation of the Antioxidant and Anti-Inflammatory Activity of Volatile Compounds and Minerals in Five Different Onion Varieties

Separations ◽  
2021 ◽  
Vol 8 (5) ◽  
pp. 57
Author(s):  
Rokayya Sami ◽  
Abeer Elhakem ◽  
Mona Alharbi ◽  
Manal Almatrafi ◽  
Nada Benajiba ◽  
...  
Keyword(s):  
Volatile Compounds ◽  
Dimethyl Sulfide ◽  
Antioxidant Activities ◽  
Dry Weight ◽  
No Production ◽  
Oxidative Stresses ◽  
Anti Inflammatory ◽  
Red Variety ◽  
A Minor

Onions contain high antioxidants compounds that fight inflammation against many diseases. The purpose was to investigate some selected bioactive activities of onion varieties (Yellow, Red, Green, Leek, and Baby). Antioxidant assays and anti-inflammatory activities such as NO production with the addition of some bioactive components were determined and analyzed by using a spectrophotometer. Gas chromatography and mass spectrometry (GC–MS) was used for the volatile compounds, while an Atomic absorption spectrometer was used for mineral determinations. Red variety achieved the highest antioxidant activities. The total flavonoids were between (12.56 and 353.53 mg Quercetin/gin dry weight) (dw) and the total phenol was (8.75–25.73 mg/g dw). Leek, Yellow and Green extracts achieved highly anti-inflammatory values (3.71–4.01 μg/mL) followed by Red and Baby extracts, respectively. The highest contents of sodium, potassium, zinc, and calcium were established for Red onions. Furfuraldehyde, 5-Methyl-2-furfuraldehyde, 2-Methyl-2-pentenal, and 1-Propanethiol were the most predominant, followed by a minor abundance of the other compounds such as Dimethyl sulfide, Methyl allyl disulfide, Methyl-trans-propenyl-disulfide, and Methyl propyl disulfide. The results recommend that these varieties could act as sources of essential antioxidants and anti-inflammatories to decrease inflammation and oxidative stresses, especially red onions that recorded high activities.

scholarly journals Hierarchical Porous, N-Containing Carbon Supports for High Loading Sulfur Cathodes

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 408
Author(s):  
Jae-Woo Park ◽  
Hyun Jin Hwang ◽  
Hui-Ju Kang ◽  
Gazi A. K. M. Rafiqul Bari ◽  
Tae-Gyu Lee ◽  
...  
Keyword(s):  
High Energy ◽  
High Energy Density ◽  
High Loading ◽  
Carbon Supports ◽  
Structure Directing Agent ◽  
Shuttle Effect ◽  
Main Challenge ◽  
Hierarchical Porous ◽  
Hollow Carbon ◽  
A Minor

The lithium-polysulfide (LiPS) dissolution from the cathode to the organic electrolyte is the main challenge for high-energy-density lithium-sulfur batteries (LSBs). Herein, we present a multi-functional porous carbon, melamine cyanurate (MCA)-glucose-derived carbon (MGC), with superior porosity, electrical conductivity, and polysulfide affinity as an efficient sulfur support to mitigate the shuttle effect. MGC is prepared via a reactive templating approach, wherein the organic MCA crystals are utilized as the pore-/micro-structure-directing agent and nitrogen source. The homogeneous coating of spherical MCA crystal particles with glucose followed by carbonization at 600 °C leads to the formation of hierarchical porous hollow carbon spheres with abundant pyridinic N-functional groups without losing their microstructural ordering. Moreover, MGC enables facile penetration and intensive anchoring of LiPS, especially under high loading sulfur conditions. Consequently, the MGC cathode exhibited a high areal capacity of 5.79 mAh cm−2 at 1 mA cm−2 and high loading sulfur of 6.0 mg cm−2 with a minor capacity decay rate of 0.18% per cycle for 100 cycles.

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