Contributions to ecological chemistry CXII balance of conversion of buturon‐14C in wheat under outdoor conditions 1

Abstract

The urea herbicide buturon (N‐[p‐chlorophenyl] ‐N’ ‐methyl‐N’ ‐isobutinyl‐urea), ¹⁴C‐labeled, was sprayed on winter wheat as an aqueous formulation (2.98 kg/ha) under outdoor conditions. Upon harvest (three months after application), a total of 49. 2% of the applied radiocarbon was recovered: 2.0% in the plants, 46.9% in the soil, and 0.3% in the leaching water (depth > 50 cm); less than 0.1% was in the grains (0.464 ppm). Only about half of the radioactivity present in plants could be recovered under mild extraction conditions; about half of this was unchanged buturon. In straw and husk extracts, the following metabolites were identified by gaschromatography/mass spectrometry: N‐(p‐chlorophenyl)‐N‐methyl‐O‐methyl‐carbamate (metabolite I), N‐phenyl‐N’ ‐formyl‐urea (metabolite II), two unstable metabolites giving (p‐chlorophenyl)‐isocyanate upon purification (metabolites III and IV), N‐(p‐chlorophenyl)‐N’ ‐methyl‐N’ ‐isobutenylol‐urea (metabolite V), p‐chloroformanilide (metabolite VI) and biologically bound p‐chloroaniline (metabolite VII). In the root and basal stem extract, the following metabolites were identified by gas chromatography/mass spectrometry: N‐(p‐chlorophenyl)‐O‐methyl‐carbamate (metabolite VIII) and N‐(p‐chlorophenyl)‐N’ ‐methyl‐urea (metabolite IX).     

Influence of x-ray diffraction sample preparation on quantitative mineralogy: implications for chromate waste treatment

Powders of chromite ore processing residue (COPR) were mineralogically evaluated using quantitative X-ray powder diffraction (XRPD) to illustrate the impacts of sample preparation procedures. Chromite ore processing residue is strongly alkaline, reactive, contains minerals of varying hardness and absorption coefficients, and exhibits significant amorphicity. This poses a challenge to produce powders for XRPD analysis that are sufficiently fine and of uniform particle size while avoiding mineral reactions and overgrinding effects. Dry, hand pulverization to different grain sizes, and wet, mechanical pulverization (micromilling) using four milling liquids (cyclohexane, isopropanol, ethanol, and water), and variable milling durations (up to 15 min) were evaluated. Micromilling with a light, nonpolar, highly evaporative liquid such as cyclohexane with a milling time of 5 min mitigated systematic errors such as microabsorption and preferred orientation as it produced finer and more uniform particle size distributions than the hand-pulverized powders, while simultaneously affording the least time for sample preparation. Conversely, the use of water as milling liquid resulted in extensive hydration reactions during sample preparation, causing mischaracterization and significant underestimation of its reactive brownmillerite content, which can complicate the remediation design process for COPR. Hand pulverization emerged as a necessary complement to quantify Cr(VI)-containing, softer minerals destroyed during mechanical milling, the quantification of which has also important implications for COPR treatment design. The findings of this study may be applicable in a variety of geochemically complicated and reactive environmental media (metal-contaminated soils, stabilized/solidified media, inorganic waste), and points to the importance of the sample preparation method to obtain reliable quantitative XRPD results.     

e-Serem – A Web-Based Manual For The Estimation of Emission Reductions From JI and CDM Projects

This paper presentse-SEREM (Smart Emission ReductionEstimation Manual), a cost-free, easilyaccessed and updated, web-based manual forestimating emission reductions from Joint Implementation (JI) andClean Development Mechanism (CDM) projects. e-SEREM's main functions arethe selection of a benchmark for a specificproject type in the power or heat sectorand the calculation of the annual andcumulative emission reductions accrued bythis project for its crediting lifetime.e-SEREM was developed in order to test itsapplicability and practicality in assistingproject developers and evaluators toelaborate baselines easily and calculatethe emission credits earned by candidate JIor CDM projects hosted in several countries.     

Selective survival of only the healthy fetus following prenatal diagnosis of thalassaemia major in binovular twin gestation

Selective feticide is the procedure of choice when, in twin binovular pregnancy, only one of the fetuses is shown to be affected. As the probabilities for this condition are almost 1:2 when the genetic disease is due to homozygosity for two autosomal recessive genes, the problem is expected to occur frequently among the ever increasing number of couples seeking prenatal diagnosis of thalassaemia and the haemoglobinopathies. The present report is the first case of this condition and the ninth in the overall medical literature.     

Swelling related to ettringite crystal formation in chromite ore processing residue

Several million tons of Chromite Ore Processing Residue (COPR) were deposited at two sites in New Jersey and Maryland, USA, and over time they exhibited extensive heaving phenomena. Ettringite, a needle-shaped mineral and an expansive mineral commonly recognized in the literature concerning cement- and soil, has been identified extensively in numerous COPR samples collected from these sites. It was therefore believed that ettringite formation and its crystal growth are strongly associated with COPR heaving. We investigated the correlation between ettringite and the heaving phenomena in COPR materials that contained no initial ettringite. Two identical COPR samples were exposed to a 4% w/w sulfate solution (25°C, 50°C) in a confined swell test apparatus. Both swell test samples were analyzed by means of X-ray powder diffraction. The peak intensities of newly formed ettringite were more pronounced in the sample tested at 50°C, and swell development was only observed in this sample. Scanning electron microscopy analyses revealed well-crystallized ettringite needles exceeding 40 μm in length for this sample, while ettringite crystals less than 15 μm in length formed in the sample tested at 25°C. Therefore, the results suggest that the quantity of ettringite and the extent of crystallization play a key role in the heave of COPR.     

A kinetic analysis of solid waste composting at optimal conditions

Six municipal solid waste (MSW) and yard waste components (food waste, mixed paper, yard waste, leaves, branches, grass clippings) were aerobically decomposed to measure the extent of decomposition under near optimal conditions. Decomposition was characterized by at least two principal stages, for most components, as was indicated by the carbon dioxide production rates. An aerobic biodegradation conceptual model is presented here based on the principle that solids hydrolysis is the rate-limiting step during solid waste composting. The mineralizable solid carbon of each solid waste component was assumed to comprise the readily, the moderately and the slowly (or refractory) hydrolysable carbons, each hydrolyzing at different rates to aqueous (water soluble) carbon. Aqueous carbon mineralizes to CO2 at rapid rates that are not rate-limiting to the process. Solids hydrolysis rate constants were calculated after fitting the experimentally determined carbon dioxide production rate data to model results. Hydrolysis rates for the readily hydrolysable carbon in all components ranged from approximately 0.06 to 0.1 d(-1); hydrolysis rates for the moderately hydrolysable carbon ranged from 0.005 to 0.06 d(-1). Leaves, branches and grass clippings did not have a readily hydrolysable carbon fraction, whilst the leaves and branches had the largest slowly hydrolysable carbon fractions (70%, 82%, respectively, of the total solid organic carbon). Grass and yard waste did not contain slowly hydrolysable carbon fractions. Food waste had the largest readily hydrolysable carbon fraction and produced the highest amount of CO2 among all substrates. Moderately hydrolysable solid carbon fractions ranged from 16% to 90% of the total solid organic carbon for all substrates used.     

Important areas at sea for adult loggerhead sea turtles in the Mediterranean Sea: satellite tracking corroborates findings from potentially biased sources

Sea turtle populations worldwide suffer from reduced survival of immatures and adults due to fishery bycatch. Unfortunately, information about the whereabouts of turtles outside the breeding habitat is scarce in most areas, hampering the development of spatially explicit conservation plans. In the Mediterranean, recoveries of adult females flipper-tagged on nesting beaches suggest that the Adriatic Sea and Gulf of Gabès are important foraging areas for adults, but such information could be heavily biased (observing and reporting bias). In order to obtain unbiased data, we satellite-tracked seven loggerhead sea turtles after they completed nesting in the largest known Mediterranean rookery (Bay of Laganas, Zakynthos, Greece). Three females settled in the north Adriatic Sea, one in the south Adriatic Sea and two in the Gulf of Gabès area at the completion of their post-nesting migrations (one individual did not occupy a distinct foraging area). The concordance of tracking results with information from recoveries of flipper-tagged turtles suggests that the north Adriatic Sea and the Gulf of Gabès represent key areas for female adult Mediterranean loggerhead sea turtles.     

Assessing the alteration of physicochemical characteristics in composted organic waste in a prototype decentralized composting facility

Environmental Science and Pollution Research - This article presents the pilot experience of an integrated biowaste management system developed in Tinos island, Greece, which promoted source...     

Personal deposited dose and its influencing factors at several Greek sites: an analysis in respect to seasonal and diurnal variations

Environmental Science and Pollution Research - The deposited dose in the human respiratory tract and its influencing factors were investigated for 8 urban/suburban locations within Greek cities. A...     

The use of tailor-made acidic deep eutectic solvents for preparation of quercetin-enriched extracts from onion solid wastes

The current examination dealt with the development of a methodology to produce quercetin, a multifunctional bio-flavonoid, by designing task-specific, highly acidic deep eutectic solvents, based on glycerol and natural organic acids. The purpose was to achieve a simultaneous hydrolysis of spiraeoside, the major quercetin glycoconjugate occurring in onion solid wastes, and quercetin extraction. After an initial performance screening, the combination of glycerol/oxalic acid was identified as the highest-performing system, and further investigation showed that the most efficacious molar ratio was glycerol/oxalic acid 3:1. Further study of hydrolysis/extractions conditions suggested 30 min, at 130°C, to be the best operating conditions, giving the highest yield of 19.65 mg quercetin per grams of dry mass. The extract obtained under these conditions displayed significantly enhanced antiradical activity, compared to control extracts prepared with water or aqueous ethanol. On the other hand, results on the ferric-reducing power were rather contradictory. It is proposed that such a methodology may be implemented to valorize onion solid wastes, for the production of extracts significantly enriched in quercetin, with increased antiradical properties.