可持续发展下环境伦理与原则

可持续发展理论与实践促进了环境伦理学的发展。环境伦理也从人类中心主义的环境伦理与非人类中心主义的环境伦理的分野走向人类中心主义的环境伦理、非人类中心主义环境伦理和可持续发展的环境伦理的鼎足。可持续发展的环境伦理是合理吸收人类中心主义环境伦理和非人类中心主义环境伦理并着眼于可持续发展的环境伦理 ,它要求人们在对待环境的行为中必须善待自然、关注未来和规范行为     

Incorporation of gypsum waste in ceramic block production: Proposal for a minimal battery of tests to evaluate technical and environmental viability of this recycling process

Civil engineering-related construction and demolition debris is an important source of waste disposed of in municipal solid waste landfills. After clay materials, gypsum waste is the second largest contributor to the residential construction waste stream. As demand for sustainable building practices grows, interest in recovering gypsum waste from construction and demolition debris is increasing, but there is a lack of standardized tests to evaluate the technical and environmental viability of this solid waste recycling process. By recycling gypsum waste, natural deposits of gypsum might be conserved and high amounts of the waste by-product could be reused in the civil construction industry. In this context, this paper investigates a physical property (i.e., resistance to axial compression), the chemical composition and the ecotoxicological potential of ceramic blocks constructed with different proportions of clay, cement and gypsum waste, and assesses the feasibility of using a minimal battery of tests to evaluate the viability of this recycling process. Consideration of the results for the resistance to axial compression tests together with production costs revealed that the best formulation was 35% of plastic clay, 35% of non-plastic clay, 10% of Portland cement and 20% of gypsum waste, which showed a mean resistance of 4.64 MPa. Energy dispersive X-ray spectrometry showed calcium and sulfur to be the main elements, while quartz, gypsum, ettringite and nacrite were the main crystalline compounds found in this formulation. Ecotoxicity tests showed that leachate from this formulation is weakly toxic toward daphnids and bacteria (EC_20% = 69.0 and 75.0, respectively), while for algae and fish the leachate samples were not toxic at the EC_50% level. Overall, these results show that the addition of 20% of gypsum waste to the ceramic blocks could provide a viable substitute for clay in the ceramics industry and the tests applied in this study proved to be a useful tool for the technical and environmental evaluation of this recycling process, bacterial and daphnid tests being more sensitive than algae and fish tests.     

冷冻固定化硝化菌去除废水中氨氮的研究

采用聚乙烯醇(PVA)循环冷冻法制备固定化硝化菌颗粒,经活化后在颗粒填充率为9％的三相流化床中进行氨氮废水处理试验。处理低浓度氨氮有机废水(NH3-N质量浓度为75mg／L．COD约为400mg／L,水力停留时间为4h)时,NH3-N去除率约为90％,COD、TIN的去除率可达82％和60％左右;处理高浓度氨氮废水(NH3-N质量浓度450～500mg／L,水力停留时间为20h)时,NH3-N去除率在98％以上,氨氧化产物中NO2^--N质量分数在95％以上,为亚硝酸盐反硝化提供了有利条件。用该法制成的硝化菌颗粒寿命在3个月以上。     

Denning behaviour of the European badger (Meles meles) correlates with bovine tuberculosis infection status

Heterogeneities in behaviours of individuals may underpin important processes in evolutionary biology and ecology, including the spread of disease. Modelling approaches can sometimes fail to predict disease spread, which may partly be due to the number of unknown sources of variation in host behaviour. The European badger is a wildlife reservoir for bovine tuberculosis (bTB) in Britain and Ireland, and individual behaviour has been demonstrated to be an important factor in the spread of bTB among badgers and to cattle. Radio-telemetry devices were deployed on 40 badgers from eight groups to investigate patterns of den (sett) use in a high-density population, where each group had one or two main and three to eight outlier setts in their territory. Badgers were located at their setts for 28 days per season for 1 year to investigate how patterns differed between individuals. Denning behaviour may have a strong influence on contact patterns and the transmission of disease. We found significant heterogeneity, influenced by season, sex and age. Also, when controlling for these, bTB infection status interacting with season was highly correlated with sett use. Test-positive badgers spent more time away from their main sett than those that tested negative. We speculate that wider-ranging behaviour of test-positive animals may result in them contacting sources of infection more frequently and/or that their behaviour may be influenced by their disease status. Measures to control infectious diseases might be improved by targeting functional groups, specific areas or times of year that may contribute disproportionately to disease spread.     

Production of monoclonal antibody against doxycycline for immunoassay of seven tetracyclines in bovine muscle and milk

The objective of this study was to produce a generic monoclonal antibody for multi-determination of the residues of tetracycline drugs in bovine muscle and milk. Two new immunogens of doxycycline were prepared that were used to produce the monoclonal antibodies. Results showed the obtained antibodies simultaneously recognized seven tetracycline drugs (doxycycline, tetracycline, chlortetracycline, oxytetracycline, minocycline, methacycline, demeclocycline). The obtained antibodies and three coating antigens were arranged into six combinations to optimize the reagents combination. After comparison of the performances of these combinations, a heterologous indirect competitive ELISA was then used to determine the seven tetracyclines in bovine muscle and milk. The crossreactivities to the seven analytes were in the range of 47%–102% and the limits of detection were in the range of 1.5–6.9 ng/mL depending on the compound. The recoveries of the seven drugs from fortified blank samples were in the range of 75.3%–106.8% with coefficients of variation lower than 10.9%. Therefore, this method could be used as a multi-analytes screen tool for routine monitoring of the residues of these tetracycline drugs in bovine muscle and milk.     

Development and application of methodology for determining 1,2‐dibromo‐3‐chloropropane (DBCP) in ambient air

Abstract

Ametpreviously described by Mann et al.¹ for the determination of hexachlorobenzene in air was modified to detect DBCP in air at the level of 0.02 ppb (by volume). The method utilizes Chromosorb 101 as a trapping medium with subsequent analysis of the eluted DBCP by electron capture ‐ gas chromatography. The procedure was tested using air flows of 1 1/min to 5 1/min for sampling periods of 30 min to 3 hr. Recoveries of greater than 90% were obtained for DBCP levels ranging from 0.07 ppb to 20 ppm. More than 90% of the DBCP stored on Chromosorb 101 at ambient temperature for one month was recovered. A one‐half acre field plot was sprayed with DBCP using the drench method. Air samples were taken from the breathing zone of the applicator during the mixingspraying and clean‐up procedures. Air samples were also taken periodically around the perimeter of the plot for up to 7 days after spraying.     

Microbial ecotoxicity and mutagenicity of 1-hydroxypyrene and its photoproducts.

1-Hydroxypyrene (1-HP) is a carcinogenic and slightly water-soluble polycyclic aromatic hydrocarbon. Ecotoxicity and mutagenicity of 1-HP and its photoproducts, and the effect of Mn2+ and Cu2+ on their mutagenicity were measured with microbial assay in this study. The assay includes spread plate counting, direct counting, microbial mineralization of 14C-UL-D-glucose and Mutatox Test. At the concentration examined (0.8 microM), the photoproducts (after 1.5 h solar irradiation) of 1-HP inhibited microbial glucose mineralization activity (by 64%) after microbial assemblages of a local reservoir site were exposed for 1 day. However, heterotrophic bacteria were able to utilize 1-HP photoproducts as the growth substrates and increase viability counts by up to 4.75-folds. 1-HP exhibited positive response to Mutatox Test in both direct medium and S-9 medium, with the lowest observable effective concentration of 0.625 microM in the test with direct medium. After photolysis, 1-HP decreased its mutagenicity. Mn2+ (312.5 microM-5 mM) and Cu2+ (6.25-100 microM) themselves are not mutagenic. However, addition of the metal ions before or after photolysis modifies the light readings of 1-HP during the test. Therefore, presence of metal ions could affect the genotoxicity of 1-HP in aquatic environments, depending on timing of the addition.     

Anaerobic co-digestion of the organic fraction of municipal solid waste with FOG waste from a sewage treatment plant: Recovering a wasted methane potential and enhancing the biogas yield

Anaerobic digestion is applied widely to treat the source collected organic fraction of municipal solid wastes (SC-OFMSW). Lipid-rich wastes are a valuable substrate for anaerobic digestion due to their high theoretical methane potential. Nevertheless, although fat, oil and grease waste from sewage treatment plants (STP-FOGW) are commonly disposed of in landfill, European legislation is aimed at encouraging more effective forms of treatment. Co-digestion of the above wastes may enhance valorisation of STP-FOGW and lead to a higher biogas yield throughout the anaerobic digestion process. In the present study, STP-FOGW was evaluated as a co-substrate in wet anaerobic digestion of SC-OFMSW under mesophilic conditions (37 °C). Batch experiments carried out at different co-digestion ratios showed an improvement in methane production related to STP-FOGW addition. A 1:7 (VS/VS) STP-FOGW:SC-OFMSW feed ratio was selected for use in performing further lab-scale studies in a 5 L continuous reactor. Biogas yield increased from 0.38 ± 0.02 L g VS_feed^?1 to 0.55 ± 0.05 L g VS_feed^?1 as a result of adding STP-FOGW to reactor feed. Both VS reduction values and biogas methane content were maintained and inhibition produced by long chain fatty acid (LCFA) accumulation was not observed. Recovery of a currently wasted methane potential from STP-FOGW was achieved in a co-digestion process with SC-OFMSW.     

Degradation of 4-aminophenol by hydrogen peroxide oxidation using enzyme from Serratia marcescens as catalyst

This paper reports on the degradation of 4-aminophenol using hydrogen peroxide as oxidizer and the enzyme from Serratia marcescens AB 90027 as catalyst. The effecting factors during degradation and the degrading mechanism were studied. Also, the location of the enzyme in the cell, which could catalyze the degradation of 4-aminophenol, was analyzed. The results showed that to degrade 50 mL of 4-aminophenol whose concentration was 500 mg/L, the optimal conditions were: volume of H₂O₂ = 3 mL, temperature = 40–60°C and pH = 9–10. In the degradation process, 4-aminophenol was first converted to benzoquinone and NH₃, then organic acids including maleic acid, fumaleic acid, and oxalic acid were formed, and then finally CO₂ and H₂O were generated as final products. The enzyme that could catalyze the degradation of 4-aminophenol was mainly extracellular enzyme. Translated from Environmental Chemistry, 2006, 25(2): 141–144 [译自: 环境化学]     

Appropriate combination of physico-chemical methods (coagulation/flocculation and ozonation) for the efficient treatment of landfill leachates

An integrated technique consisted of ozonation and coagulation/flocculation processes was studied, aiming to provide an efficient method for the treatment of stabilized/biologically pre-treated leachates, in order to reduce the organic pollutants' content to concentration values lower than the corresponding limits, imposed by the legislation. Leachates were collected from a municipal landfill site; samples containing around 1000 mg l(-1) COD and BOD(5)/COD ratio about 0.17 were treated by using two different processes or combinations between them, i.e. ozonation, coagulation-flocculation, ozonation followed by coagulation/flocculation and coagulation/flocculation followed by ozonation. The application of single ozonation resulted to the efficient removal of color and organic loading, due to the respective oxidation, induced by ozonation; however, COD values lower than 200 mg l(-1) could be only achieved after prolonged reaction times and for high ozone production rates. The coagulation of leachate samples was studied by the addition of ferric chloride or poly-aluminum chloride agents at various dosages. Maximum COD removal rates (up to 72%) were achieved by the addition of 7 mM Fe, or of 11 mM Al respectively. However, final COD values higher than 200 mg l(-1) were obtained indicating the requirement of an additional treatment step. Pre-ozonation followed by coagulation/flocculation was not found to be an efficient treatment approach for this aim, but coagulation/flocculation followed by ozonation, was proved to be an efficient process for the reduction of COD to lower than 180 mg l(-1).