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811.
Juan Huang Yanli Feng Jiamo Fu Guoying Sheng 《Environmental science and pollution research international》2010,17(5):1129-1136
Background, aim, and scope
Carbonyl compounds have been paid more and more attention because some carbonyl species have been proven to be carcinogenic or a risk for human health. Plant leaves are both an important emission source and an important sink of carbonyl compounds. But the research on carbonyl compounds from plant leaves is very scarce. In order to make an approach to the emission mechanism of plant leaves, a new method was established to extract carbonyl compounds from fresh plant leaves. 相似文献812.
Hauke Reuter Ulrike Middelhoff Frieder Graef Richard Verhoeven Thomas Batz Martin Weis Gunther Schmidt Winfried Schröder Broder Breckling 《Environmental science and pollution research international》2010,17(8):1479-1490
Background, aim and scope
European legislation stipulates that genetically modified organisms (GMO) have to be monitored to identify potential adverse environmental effects. A wealth of different types of monitoring data from various sources including existing environmental monitoring programmes is expected to accumulate. This requires an information system to efficiently structure, process and evaluate the monitoring data. 相似文献813.
814.
Ikechukwu D. Anyaogu Paul M. Ejikeme John A. Ibemesi 《Journal of Polymers and the Environment》2010,18(2):104-115
Soybean oil (SBO) was dimerized and the crude dimer acid product reacted with 1,2-phenylene diamine at 210 ± 5 °C under inert
atmosphere to obtain fatty polyamide (FPA). The FPA was used to modify a commercial alkyd resin by reacting a mixture of the
alkyd resin with 5 wt% of FPA at 120 °C for 80 min under inert atmosphere. The FTIR spectrum of the FPA modified resin showed
evidence of higher degree of H-bonding than was found for the unmodified alkyd. White gloss coatings of 15, 20, 25, and 30%
solids were formulated from the modified and unmodified resins and examined for performance with respect to: leveling, sag
resistance, drying time, pigment settling, skinning tendency and film hardness. Results showed that the unmodified alkyd coatings
exhibited good leveling but poor sag resistance at all solid contents. In contrast, FPA modified alkyd coatings combined good
leveling with high sag resistance indicating their thixotropic nature. A strong tendency to pigment settling was observed
for unmodified alkyd coatings but was not observed in the FPA modified alkyd coatings. The modified alkyd coatings showed
skinning while the unmodified alkyd coatings did not skin. A 30% solids coating formulation of the FPA modified resin showed
shorter surface dry time but longer hard dry time than the unmodified alkyd resin coating. 相似文献
815.
Romeu Casarano Denise F. S. Petri Michael Jaffe Luiz H. Catalani 《Journal of Polymers and the Environment》2010,18(1):33-44
A new aliphatic block copolyester was synthesized in bulk from transesterification techniques between poly((R)-3-hydroxybutyrate)
(PHB) and poly(isosorbide succinate) (PIS). Additionally, other two block copolyesters were synthesized in bulk either from
transesterification reactions involving PHB and poly(l-lactide) (PLLA) or from ring-opening copolymerization of l-lactide and hydroxyl-terminated PHB, as result of a previous transesterification reactions with isosorbide. Two-component
blends of PHB and PIS or PLLA were also prepared as comparative systems. SEC, MALDI-TOF mass spectrometry (MALDI-TOFMS), 1H and 13C NMR spectroscopy, WAXD, solubility tests, and TG thermal analysis were used for characterization. The block copolymer structures
of the products were evidenced by MALDI-TOFMS, 13C NMR, and WAXD data. The block copolymers and the corresponding binary blends presented different solubility properties,
as revealed by solubility tests. Although the incorporation of PIS sequences into PHB main backbone did not enhance the thermal
stability of the product, it reduced its crystallinity, which could be advantageous for faster biodegradation rate. These
products, composed of PHB and PIS or PLLA sequences, are an interesting alternative in biomedical applications. 相似文献
816.
Rachana Bhatt K. C. Patel Ujjval Trivedi 《Journal of Polymers and the Environment》2010,18(2):141-147
An extracellular poly(3-hydroxybutyrate) (PHB) depolymerase produced by a thermotolerant fungal soil isolate, Aspergillus fumigatus 202, was purified and characterized. Maximum PHB depolymerase production was obtained at the end of 48 h with initial medium
pH 7.0 and 45 °C in Bushnell Haas Minerals medium containing PHB as sole source of carbon. The PHB depolymerase was purified
using size exclusion chromatography to a fold purification of 20.62 and 61.62% yield. SDS-PAGE and isoelectric focusing revealed
the molecular weight and pI of the purified enzyme as 63,744 Da and 4.2, respectively. N-terminal amino acid sequence of purified
enzyme was HAXDAYLVK. This non-glycosylated enzyme was most active at pH 9.0 and 45 °C. Purified enzyme was inactivated by
N-bromosuccinimide and dithiothreitol suggesting the involvement of tryptophan residues and disulfide bonds at its active
site. Nonionic detergents like Tween 20, Tween 80 and Triton X-100 inhibited the enzyme activity. Ions like Ca+2 and Mg+2 (5 mM) increased the enzyme activity 1.5 times. Fe+2 effectively inhibited the enzyme activity to 88% whereas Hg+2 completely inhibited the enzyme. 相似文献
817.
Bernadett Bartha Christian Huber Rudolf Harpaintner Peter Schröder 《Environmental science and pollution research international》2010,17(9):1553-1562
Purpose
Besides classical organic pollutants and pesticides, pharmaceuticals and their residues have nowadays become recognized as relevant environmental contaminants. The risks of these chemicals for aquatic ecosystems are well known, but information about the pharmaca-plant interactions and metabolic pathways is scarce. Therefore, we investigate the process of uptake of acetaminophen (N-Acetyl-4-aminophenol) by Brassica juncea, drug-induced defense responses and detoxification mechanisms in different plant parts. 相似文献818.
Ika Paul-Pont Xavier de Montaudouin Patrice Gonzalez Philippe Soudant Magalie Baudrimont 《Environmental science and pollution research international》2010,17(4):987-998
Introduction
Within the last decade, numerous studies have investigated the role of environmental history on tolerance to stress of many organisms. This study aims to assess if Manila clams Ruditapes philippinarum may react differently to cadmium exposure and trematode parasite infection (Himasthla elongata) depending on their origin and environmental history in Arcachon Bay (France). 相似文献819.
Jianjun Niu Pat E. Rasmussen Amanda Wheeler Ron Williams Marc Chénier 《Atmospheric environment (Oxford, England : 1994)》2010,44(2):235-245
Factors and sources affecting measurement uncertainty associated with monitoring metals in airborne particulate matter (PM) were investigated as part of the Windsor, Ontario Exposure Assessment Study (WOEAS). The assessment was made using co-located duplicate samples and a comparison of two analytical approaches: ED-XRF and ICP-MS. Sampling variability was estimated using relative percent difference (RPD) of co-located duplicate samples. The comparison of ICP-MS and ED-XRF results yields very good correlations (R2 ≥ 0.7) for elements present at concentrations that pass both ICP-MS and ED-XRF detection limits (e.g. Fe, Mn, Zn, Pb and Cu). PM concentration ranges (median, sample number) of 24-h indoor PM10 and personal PM10 filters, and outdoor PM2.5 filters were determined to be 2.2–40.7 (11.0, n = 48) μg m?3, 8.0–48.3 (11.9, n = 48) μg m?3, and 17.1–42.3 (21.6, n = 18) μg m?3, respectively. The gravimetric analytical results reveal that the variations in PM mass measurements for same-day sampling are insignificant compared to temporal or spatial variations: 92%, 100% and 96% of indoor, outdoor and personal duplicate samples, respectively, pass the quality criteria (RPD ≤ 20%). Uncertainties associated with ED-XRF elemental measurements of S, Ca, Mn, Fe and Zn for 24-h filter samples are low: 78%–100% of the duplicate samples passed the quality criteria. In the case of 24-h filter samples using ICP-MS, more elements passed the quality criteria due to the lower detection limits. These were: Li, Na, K, Ca, Si, Al, V, Fe, Mn, Co, Cu, Mo, Ag, Zn, Pb, As, Mg, Sb, Sn, Sr, Th, Ti, Tl, and U. Low air concentrations of metals (near or below instrumental detection limits) and/or inadvertent introduction of metal contamination are the main causes for excluding elements based on the pass/fail criteria. Uncertainty associated with elemental measurements must be assessed on an element-by-element basis. 相似文献
820.
Solen Quéguiner Luc Musson Genon Yelva Roustan Philippe Ciffroy 《Atmospheric environment (Oxford, England : 1994)》2010,44(7):958-967
A modeling approach has been developed to estimate the contribution of atmospheric emissions to the contamination of leaf vegetables by persistent organic pollutants (POPs). It combines an Eulerian chemical transport model for atmospheric processes (Polair3D/Polyphemus) with a fate and transport model for soil and vegetation (Ourson). These two models were specifically adapted for POPs. Results are presented for benzo(a)pyrene (BaP). As expected no accumulation of BaP in leaf vegetables appears during the growth period for each harvest over the 10 years simulated. For BaP and leaf vegetables, this contamination depends primarily on direct atmospheric deposition without chemical transfer from the soil to the plant. These modeling results are compared to available data. 相似文献