High-molecular weight sulfur-containing aromatics refractory to weathering as determined by Fourier transform ion cyclotron resonance mass spectrometry

Biomarkers and low-molecular weight polyaromatic compounds have been extensively studied for their fate in the environment. They are used for oil spill source identification and monitoring of weathering and degradation processes. However, in some cases, the absence or presence of very low concentration of such components restricts the access of information to spill source. Here we followed the resistance of high-molecular weight sulfur-containing aromatics to the simulated weathering condition of North Sea crude oil by ultra high-resolution Fourier transform ion cyclotron resonance mass spectrometry. The sulfur aromatics in North Sea crude having double bond equivalents (DBE) from 6 to 14 with a mass range 188-674 Da were less influenced even after 6 months artificial weathering. Moreover, the ratio of dibenzothiophenes (DBE 9)/naphthenodibenzothiophenes (DBE 10) was 1.30 and 1.36 in crude oil and 6 months weathered sample, respectively reflecting its weathering stability. It also showed some differences within other oils. Hence, this ratio can be used as a marker of the studied crude and accordingly may be applied for spilled oil source identification in such instances where the light components have already been lost due to environmental influences.     

Treatment of distillery spent-wash by ozonation and biodegradation: significance of pH reduction and inorganic carbon removal before ozonation.

This study is aimed at exploring strategies for mineralization of refractory compounds in distillery effluent by anaerobic biodegradation/ozonation/aerobic biodegradation. Treatment of distillery spent-wash used in this research by anaerobic-aerobic biodegradation resulted in overall COD removal of 70.8%. Ozonation of the anaerobically treated distillery spent-wash was carried out as-is (phase I experiments) and after pH reduction and removal of inorganic carbon (phase II experiments). Introduction of the ozonation step resulted in an increase in overall chemical oxygen demand (COD) removal, with the highest COD removals of greater than 95% obtained when an ozone dose of approximately 5.3 mg ozone absorbed/mg initial total organic carbon was used. The COD removal during phase II experiments was slightly superior compared with phase I experiments at similar ozone doses. Moreover, efficiency of ozone absorption from the gas phase into distillery spent-wash aliquots was considerably enhanced during phase II experiments.     

Water-holding capacity of earthworms’ vermicompost made of sugar industry waste (press mud) in mono- and polyculture vermireactors

Efforts were made to recycle sugar industry waste ‘press mud’ (PM) with an objective to ascertain the water-holding capacities with monoculture vermireactor systems using Eisenia fetida (MVR1); Eudrilus eugeniae (MVR2); Megascolex megascolex (MVR3); and polyculture vermireactor systems using Eisenia fetida + Eudrilus eugeniae (PVR1); Eisenia fetida + Megascolex megascolex (PVR2); Eudrilus eugeniae + Megascolex megascolex (PVR3). The vermicompost harvested after 40 days was subjected to a standard Proctor compaction test by using 3 kg industry soil and 200 g of vermicompost for each cycle of compaction up to seven cycles. The least dry density and highest water content 0.6, 170%; 0.66, 170%; 0.71, 170% and 0.52, 210%; 0.51, 180%; 0.71, 150% for vermicomposts of MVR3, MVR2, MVR1 and PVR3, PVR2, PVR1, respectively. The monoculture reactor using Megascolex megascolex can hold 110–170% and polyculture vermireactor using indigenous Megascolex megascolex + Eudrilus eugeniae (PVR3) can hold 140–210% of water under experimental conditions. The species Megascolex megascolex used individually and in combinations with Eudrilus eugeniae are best suited for biodegradation of press mud, and composts derived are having increase water-holding capacities. The addition of VC to the soil increases water-holding capacity and by maintaining evaporation losses to minimum as good adsorbent of atmospheric moisture eventually helps in maintaining the ecology of hydrologic cycle. Increasing water-holding capacity is one of the soil erosion control measures that influences soil productivity in both managed and natural ecosystems.     

Sustainable Water Purification and Energy Generation Over Crystalline Chitosan Grafted Polyaniline Composite

Journal of Polymers and the Environment - The present research demonstrates the design and development of a dual-compartment water purification proto-plant for microbial degradation of organic...     

Development of an algorithm for an EEG-based driver fatigue countermeasure

PROBLEM: Fatigue affects a driver's ability to proceed safely. Driver-related fatigue and/or sleepiness are a significant cause of traffic accidents, which makes this an area of great socioeconomic concern. Monitoring physiological signals while driving provides the possibility of detecting and warning of fatigue. The aim of this paper is to describe an EEG-based fatigue countermeasure algorithm and to report its reliability. METHOD: Changes in all major EEG bands during fatigue were used to develop the algorithm for detecting different levels of fatigue. RESULTS: The software was shown to be capable of detecting fatigue accurately in 10 subjects tested. The percentage of time the subjects were detected to be in a fatigue state was significantly different than the alert phase (P<.01). DISCUSSION: This is the first countermeasure software described that has shown to detect fatigue based on EEG changes in all frequency bands. Field research is required to evaluate the fatigue software in order to produce a robust and reliable fatigue countermeasure system. IMPACT ON INDUSTRY: The development of the fatigue countermeasure algorithm forms the basis of a future fatigue countermeasure device. Implementation of electronic devices for fatigue detection is crucial for reducing fatigue-related road accidents and their associated costs.     

Effect of metals on a siderophore producing bacterial isolate and its implications on microbial assisted bioremediation of metal contaminated soils

A bacterial isolate producing siderophore under iron limiting conditions, was isolated from mangroves of Goa. Based on morphological, biochemical, chemotaxonomical and 16S rDNA studies, the isolate was identified as Bacillus amyloliquefaciens NAR38.1. Preliminary characterization of the siderophore indicated it to be catecholate type with dihydroxy benzoate as the core component. Optimum siderophore production was observed at pH 7 in mineral salts medium (MSM) without any added iron with glucose as the carbon source. Addition of NaCl in the growth medium showed considerable decrease in siderophore production above 2% NaCl. Fe⁺² and Fe⁺³ below 2 μM and 40 μM concentrations respectively, induced siderophore production, above which the production was repressed. Binding studies of the siderophore with Fe⁺² and Fe⁺³ indicated its high affinity towards Fe⁺³. The siderophore concentration in the extracellular medium was enhanced when MSM was amended with essential metals Zn, Co, Mo and Mn, however, decreased with Cu, while the concentration was reduced with abiotic metals As, Pb, Al and Cd. Significant increase in extracellular siderophore production was observed with Pb and Al at concentrations of 50 μM and above. The effect of metals on siderophore production was completely mitigated in presence of Fe. The results implicate effect of metals on the efficiency of siderophore production by bacteria for potential application in bioremediation of metal contaminated iron deficient soils especially in the microbial assisted phytoremediation processes.     

Biodegradation of Poly(ε-caprolactone) (PCL) Film by <Emphasis Type="Italic">Alcaligenes faecalis</Emphasis>

The biodegradation behavior of PCL film with high molecular weight (80,000 Da) in presence of bacterium Alcaligenes faecalis and the analysis of degraded polymer film have been carried out. Thin Films of PCL were prepared by means of solution casting method and the bacterial degradation behavior was carried in basal medium, in presence of bacteria with time variation after UV treatment. It was observed that after UV treatment the degradation of polymer film was increased and the degradation rate followed a three steps degradation mechanism. The degraded polymer film was analyzed by means of Differential Scanning Calorimeter (DSC), Thermo Gravimetric Analyzer (TGA) and Fourier Transform Infrared Spectroscope (FTIR). DSC results revealed that at the initial stages of the degradation up to 15–20 days, the bacterium preferentially degrades the amorphous parts of the polymer film over the crystalline zone. Thermo gravimetric analysis highlighted the low temperature stability of degraded films with extent of degradation. FTIR results showed the chain scission mechanism of the polymer chains and also supported the preferential degradation of amorphous phase over crystalline phase in the initial stages of the degradation.