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351.
Three cultures were enriched from cork boiling wastewater using tannic acid as the selective carbon substrate, at 25 degrees C and pH 7.2, 25 degrees C and pH 4.7 and 50 degrees C and pH 4.7. The enrichment culture obtained at neutral pH was composed of five culturable isolates, whereas from each acidic enrichment two bacterial strains were isolated. Mesophilic isolates were Gram negative bacteria belonging to the genera Klebsiella, Pseudomonas, Stenotrophomonas and Burkholderia. Thermophilic isolates were members of the genus Bacillus. Despite the capability of the enrichment cultures to use tannic acid as single carbon and energy source, those cultures were unable to reduce the total polyphenols or the total organic carbon content of cork boiling wastewater. In order to increase the bioavailability of the organic carbon in cork boiling wastewater, biodegradation was preceded by Fenton oxidation. It was demonstrated that the combined process, using small amounts of Fenton reagents and biodegradative inoculum added almost simultaneously to cork boiling wastewater, leads to TOC reductions of more than 90%. 相似文献
352.
Mendoza G Gutierrez L Pozo-Gallardo K Fuentes-Rios D Montory M Urrutia R Barra R 《Environmental science and pollution research international》2006,13(1):67-74
- DOI: http://dx.doi.org/10.1065/espr2006.01.011
Goal, Scope and Background Chile signed the Stockholm Convention, which establishes measures to reduce or eliminate Persistent Organic Pollutants (POPs)
release into the environment, including the prohibition of their use and reduction of secondary products release, as well
as management related with waste treatment. Among POPs, PCBs are a family of 209 compounds that differ in chlorine level and
position. These substances present a wide variability in their physicochemical properties such as vapor pressure, water solubility
and partition coefficients that determine their behavior and mobility within the different environmental compartments. In
Chile, as in other countries, the use of these compounds were and continue to occur in diverse industrial applications such
as dielectric fluid in transformers and condensers, with a use in Chile of approximately 550,000 L. A sampling of bivalves
was performed during the years 2000-2002 in order to obtain information on the spatial distribution of the PCB levels for
the length of the long Chilean coast (180–540 South latitude, 4,200 km), contributing in this way to a better understanding
of the PCB trend and eventual fractionation along latitudinal gradients in Chile, using as the bivalve Perumytilus purpuratus
('Chorito Maico') bioindicator.
Methods The marine bivalves Perumytilus purpuratus were collected in 16 localities in northern and southern Chile. All samples were
lyophilized, and PCBs (51 congeners) were extracted in a Soxhlet system (24 h) with n-hexane. Samples were cleaned in florisil
and analyzed by GC-ECD. Blanks, certified reference materials and standards were processed along with the samples.
Results and Discussion The results obtained for P. purpuratus indicate a congeneric distribution profile associated to a latitudinal gradient, and
the statistical analysis of the congeneric composition of the PCBs indicated five groups in relation to the molecular weight
(number of chlorines), where the lighter congeners were observed in areas corresponding to high latitudes with total PCB values
of 298 ng/g dry weight.
Conclusion P. purpuratus turns out to be a good bioindicator of PCB levels in the coastal areas of Chile due to its wide distribution.
The highest concentrations and the more volatile congeners were found in southern Chile, which could be the result of processes
of long-range transport or illegal discharge occurring in such remote areas. These results confirm previous data from the
International Mussel Watch project ten years ago.
Recommendation and Outlook Future studies are needed to confirm our findings utilizing another environmental matrix such as soil/sediments and air samples. 相似文献
353.
With the changing demographic composition of the workforce, managing diversity in organizations is an important organizational function. Organizations have employed varying approaches to diversity management (DM), resulting in varying organizational outcomes. Meanwhile, researchers have called for more theoretical development within the DM area. We present a framework rooted in social and cross‐cultural psychological research, to foster theory development and empirical testing in the area of DM. We also derive several propositions to guide future research on DM and note some boundary conditions that suggest research opportunities of their own. Our framework contributes a theoretical conceptualization that enhances our understanding of organizations' DM efforts, integrates current typologies, and suggests new directions of inquiry for management scholars as well as guidelines for practitioners in the area. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
354.
Let us consider i = 1, 2,...n alternative forest plans to be evaluated according to j = 1, 2,...m indicators of sustainability. An expert or panel of experts suggests a set of targets or desirable levels of achievement for the m indicators of sustainability considered. Within this context, an important problem is to determine the system with a higher level of achievement with respect to the targets attached by the expert to the m indicators. A natural extension of this problem involves determining a ranking of the n systems considered. A general procedure based on discrete goal programming is proposed to address these problems. The methodology is applied in a case study of a Spanish forest. 相似文献
355.
356.
Building Consensus in Environmental Impact Assessment Through Multicriteria Modeling and Sensitivity Analysis 总被引:1,自引:0,他引:1
Multicriteria decision analysis (MCDA) increasingly is being applied in environmental impact assessment (EIA). In this article,
two MCDA techniques, stochastic analytic hierarchy process and compromise programming, are combined to ascertain the environmental
impacts of and to rank two alternative sites for Mexico City’s new airport. Extensive sensitivity analyses were performed
to determine the probability of changes in rank ordering given uncertainty in the hierarchy structure, decision criteria weights,
and decision criteria performances. Results demonstrate that sensitivity analysis is fundamental for attaining consensus among
members of interdisciplinary teams and for settling debates in controversial projects. It was concluded that sensitivity analysis
is critical for achieving a transparent and technically defensible MCDA implementation in controversial EIA. 相似文献
357.
INTRODUCTION: To evaluate the benefits of road transport safety projects, planners need the monetary value of averting fatal and severe injuries. Usually, contingent valuation and risk-risk studies have been used. The contexts posed by both survey techniques do not represent the choice situation a driver faces when having to choose among alternative routes with different levels of safety. METHOD: We set up a stated choice web page survey in which individuals had to choose between two routes for a hypothetical trip between two cities; thus implicitly revealing their preferences for safety both in terms of reducing the number of fatal victims and of severely injured victims. RESULTS: For Chilean routes we were able to estimate approximate values of US$300,000 and US$140,000 for a reduction in one fatality and one severely injured victim, respectively. IMPACTS: Our evidence could be valuable for road planners in other developing nations. 相似文献
358.
Alves E Velini ED Trindade ML Cataneo AC Marino CL Mori ES Guerrini IA Furtado EL Wilcken CF 《Journal of environmental science and health. Part. B》2005,40(1):151-157
Oxidative stress generating active oxygen species has been proved to be one of the underlying agents causing tissue injury after the exposure of Eucalyptus (Eucalyptus spp.) plants to a wide variety of stress conditions. The objective of this study was to perform data mining to identify favorable genes and alleles associated with the enzyme systems superoxide dismutase, catalase, peroxidases, and glutathione S-transferase that are related to tolerance for environmental stresses and damage caused by pests, diseases, herbicides, and by weeds themselves. This was undertaken by using the eucalyptus expressed-sequence database (https//forests.esalq.usp.br). The alignment results between amino acid and nucleotide sequences indicated that the studied enzymes were adequately represented in the ESTs database of the FORESTs project. 相似文献
359.
Growth conditions,elemental accumulation and induced physiological changes in Chinese cabbage 总被引:4,自引:0,他引:4
Soils contaminated with low levels of heavy metals and other trace elements are now frequently used for vegetable growing. In this situation, heavy metals and trace elements from these polluted soils may accumulate in the agricultural plants being grown in them and thereby enter the human food chain. The objectives of this study are to elucidate the effects of growth conditions, manipulated by the crop covers, on the phytoaccumulation of elements, and to investigate the conceivable influences of these conditions on the plant biochemistry. In three consecutive years of field experiments, open air (T(0)), and floating rowcover treatments (T(1): perforated polyethylene 50 micrometers; T(2): polypropylene 17 gm(-2)) were used to produce different environmental conditions for the growth of Chinese cabbage [Brassica rapa L. (Pekinensis group) cv. 'Nagaoka 50']. Five samplings (whole tops) were carried out from transplanting to harvest and measurements of B, Al, Ag, Si and Ca concentration as well as phenolics (orto-diphenols, total phenols and anthocyanins), pectic fractions, amino acids (histidine, phenylalanine and tyrosine) and polyphenol oxidase activity, were carried out in samples. The T(1) (perforated polyethylene sheet) gave greater B, Al, Ag and Si concentration and phytoextraction (in weight units) than the open-air control. These findings can help to develop new cost-effective techniques for phytoremediation as the application of plastic covers in the field. The build-up of heavy metals in those crops would make the product less suitable for human consumption. 相似文献
360.
A big fertilizer industrial complex and a vast extension of phosphogypsum piles (12 km2), sited in the estuary formed by the Odiel and Tinto river mouths (southwest of Spain), are producing an unambiguous radioactive impact in their surrounding aquatic environment through radionuclides from the U-series. The levels and distribution of radionuclides in sediments from this estuarine system have been determined. The analyses of radionuclide concentrations and activity ratios have provided us with an interesting information to evaluate the extension, degree and routes of the radioactive impact, as well as for the knowledge of the different pathways followed for the radioactive contamination to disturb this natural system. The obtained results indicate that the main pathway of radioactive contamination of the estuary is through the dissolution in its waters of the radionuclides released by the industrial activities and their later fixation on the particulate materials. Tidal activity also plays an important role in the transport and homogenization along the estuary of the radioactivity released from the fertilizer plants. 相似文献