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281.
Emma Ter Mors Mieneke W.H. Weenig Naomi Ellemers Dancker D.L. Daamen 《Journal of environmental psychology》2010,30(4):347-357
This experimental research addresses the effectiveness of communication about complex environmental issues, depending on whether the same information is provided by multiple collaborating or by individual organizations (i.e., stakeholders). The information provided pertains to carbon dioxide capture and storage (CCS) technology, as an example of a complex environmental issue. In Studies 1 (N = 75) and 2 (N = 66) we found that participants perceived factual information from collaborating stakeholders to be of higher quality than when the same information was provided by individual stakeholders. As predicted, the expectation of diverse perspectives being represented in the collaborative information mediated this effect. In addition, in Study 3 (N = 79) the perceived dissimilarity of collaborating stakeholders was shown to be an important precondition for the collaboration effect observed in Studies 1 and 2. Finally, these studies indicate that occasional collaboration between different stakeholders does not necessarily harm the perceived credibility of each individual stakeholder. 相似文献
282.
为了考察水力停留时间(HRT)对炭纤维载体固定床厌氧反应器运行效果的影响,在进水COD分别为20 000~25 000 mg/L和40 000~45 000 mg/L2个浓度范围下,研究了不同HRT对反应器运行效果的影响。结果表明,通过HRT的调整,在达到相同有机负荷(OLR)下,进水COD为20 000~25 000 mg/L的COD去除率和产气量,明显比进水COD为40 000~45 000 mg/L的运行效果好;进水COD为20 000~25 000 mg/L,HRT为14 h,相应的OLR为41.09 kgCOD/(m3.d)时,COD去除率仍然维持在68%以上,沼气容积产气率达到14.55 m3/(m3.d)。炭纤维载体固定床厌氧反应器具有较高的COD去除率、产气效率以及抵抗低pH、高负荷冲击的能力,运行过程中没有发生反应器堵塞的现象。 相似文献
283.
284.
采用生命周期评价法研究比较了北京和上海两地纸塑铝复合包装处置阶段的环境影响。通过现场和资料调研的方式获得此阶段的能量物质的输入输出和环境外排数据。结果表明:北京和上海两地纸塑铝复合包装处置阶段的环境影响潜值分别为-0.428 Pt和9.776 Pt,其主要集中在气候变化、土地占用和无机物对健康的损害三方面;每提高10%的回收率,其环境影响潜值北京和上海可分别降低5.446 Pt和5.799 Pt;上海地区纸塑铝复合包装处置阶段对环境的影响在任何同回收率的情况都要高于北京地区,其主要原因是上海地区填埋产生的温室气体释放量过大和再生企业距离打包点较远。 相似文献
285.
286.
Yamaguchi N Nakano M Takamatsu R Tanida H 《Journal of environmental radioactivity》2010,101(6):451-9983
The transformation of inorganic iodine (I− and IO3−) incubated in soils with varying amounts of organic matter (Andosols from the surface layer of an upland field and forest, as well as Acrisols from surface and subsurface layers of an upland field) was investigated by using the iodine K-edge X-ray absorption near-edge structure (XANES). After 60 d of reaction, both I− and IO3− were transformed into organoiodine in surface soils containing sufficient amounts of organic matter, whereas IO3− remained unchanged in the subsurface soil of Acrisols with low organic matter contents. Transformation of IO3− into organoiodine was not retarded when the microbial activity in soil was reduced by γ-ray irradiation, suggesting that microbial activity was not essential for the transformation of inorganic iodine into organoiodine. Soil organic matter has the ability to transform inorganic iodine into organoiodine. 相似文献
287.
《Journal of environmental science and health. Part. B》2013,48(4):533-549
Abstract The biotransformation of the nonylphenol isomer [ring-U-14C]-4-(3′,5′-dimethyl-3′-heptyl)-phenol (4-353-NP, consisting of two diastereomers) was studied in soybean and Agrostemma githago cell suspension cultures. With the A. githago cells, a batch two-liquid-phase system (medium/n-hexadecane 200:1, v/v) was used, in order to produce higher concentrations and amounts of 4-353-NP metabolites for their identification; 4-353-NP was applied via the n-hexadecane phase. Initial concentrations of [14C]-4-353-NP were 1 mg L?1 (soybean), and 5 and 10 mg L?1 (A. githago). After 2 (soybean) and 7 days (A. githago) of incubation, the applied 4-353-NP was transformed almost completely by both plant species to four types of products: glycosides of parent 4-353-NP, glycosides of primary 4-353-NP metabolites, nonextractable residues and unknown, possibly polymeric materials detected in the media. The latter two products emerged especially in soybean cultures. Portions of primary metabolites amounted to 19–22% (soybean) and 21–42% of applied 14C (A. githago). After liberation from their glycosides, the primary 4-353-NP metabolites formed by A. githago were isolated by HPLC and examined by GC-EIMS as trimethylsilyl derivatives. In the chromatograms, eight peaks were detected which due to their mass spectra, could be traced back to 4-353-NP. Seven of the compounds were side-chain monohydroxylated 4-353-NP metabolites, while the remaining was a (side-chain) carboxylic acid derivative. Unequivocal identification of the sites of hydroxylation/oxidation of all transformation products was not possible. The main primary metabolites produced by A. githago were supposed to be four diastereomers of 6′-hydroxy-4-353-NP (about 80% of all products identified). It was concluded that plants contribute to the environmental degradation of the xenoestrogen nonylphenol; the toxicological properties of side-chain hydroxylated nonylphenols remain to be examined. 相似文献
288.
《Journal of environmental science and health. Part. B》2013,48(4):577-588
Abstract A study was undertaken to determine the effect of Cu(II) in degradation of methylparathion (o,o-dimethyl o, 4-nitrophenyl phosphoriotioate) in acid medium. Initial electrochemical characterization of Cu(II) and methylparathion was done in an aqueous medium at a pH range of 2–7. Cu(II) was studied in the presence of different anions and it was observed that its electroactivity depends on pH and is independent of the anion used. Methylparathion had two reduction signals at pH ≤ 6 and only one at pH > 6. The pesticide's transformation kinetic was then studied in the presence of Cu(II) in acid buffered aqueous medium at pH values of 2, 4, and 7. Paranitrophenol appeared as the only electroactive product at all three pH values. The reaction was first order and had k values of 5.2 × 10?3 s?1 at pH 2, 5.5 × 10?3 s?1 at pH 4 and 9.0 × 10?3 s?1 at pH 7. It is concluded that the principal degradation pathway of methylparathion in acid medium is a Cu(II) catalyzed hydrolysis reaction. 相似文献
289.
《Journal of environmental science and health. Part. B》2013,48(5-6):757-764
Abstract A laboratory pot experiment was conducted to study the effect of amending soil with four different sources of organic matter on the degradation rate of α and β endosulfan isomers. Poultry by-product meal, poultry manure, dairy manure, and municipal solid waste compost were cured, dried, ground (<1 mm) and thoroughly mixed with a calcareous soil at a rate of 2% and placed in plastic pots. Endosulfan was added at the rate of 20 mg kg?1. The moisture level was kept near field capacity and the pots were kept at room temperature. Soil sub-samples, 100 g each, were collected from every pot at days 1, 8, 15, 22, 29, 43, and 57 for the measurement of endosulfan isomers. Endosulfan residues were extracted from the soil samples with acetone. The supernatant was filtered through anhydrous sodium sulphate, 5 mL aliquot was diluted to 25 mL with hexane, mixed well, and then two sub-samples from the filtrates were analyzed for α and β endosulfan isomers by gas chromatography. The results indicated that the half-life (T ½) of α-endosulfan in the poultry by-product meal treatment was 15 days compared to about 22 days in the other treatments. The T ½ of β-endosulfan was 22 days in the poultry by-product meal treatment and followed a bi-phasic pattern, 57 days in the municipal solid waste compost treatment and the extrapolated T ½ was about 115 days for the other three treatments. 相似文献
290.
In this study, different concentrations of transfluthrin and metofluthrin have been assayed for genotoxicity by using the Wing Spot Test on Drosophila melanogaster. Standard cross was used in the experiment. Third-instar larvae that were trans-heterozygous for the two genetic markers mwh and flr3 were treated at different concentrations (0.0103 mg mL−1, 0.103 mg mL−1 for transfluthrin and 6 μg mL−1, 60 μg mL−1 for metofluthrin) of the test compounds. Feeding ended with pupation of the surviving larvae and the genetic changes induced in somatic cells of the wing’s imaginal discs lead to the formation of mutant clones on the wing blade. Results indicated that two experimental concentrations of transfluthrin and 60 μg mL−1 metofluthrin showed mutagenic and recombinogenic effects in both the marker-heterozygous (MH) flies and the balancer-heterozygous (BH) flies. 相似文献