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901.
While scientific understanding of environmental issues develops through careful observation, experiment and modelling, the application of such advances in the day to day world is much less clean and tidy. Merseyside in northwest England has an industrial heritage from the earliest days of the industrial revolution. Indeed, the chemical industry was borne here. Land contamination issues are rife, as are problems with air quality. Through the examination of one case study for each topic, the practicalities of applied science are explored. An integrated, multidisciplinary response to pollution needs more than a scientific risk assessment. The needs of the various groups (from public to government) involved in the situations must be considered, as well as wider, relevant contexts (from history to European legislation), before a truly integrated response can be generated. However, no such situation exists in isolation and the introduction of environmental investigations and the exploration of suitable, integrated responses will alter the situation in unexpected ways, which must be considered carefully and incorporated in a rolling fashion to enable solutions to continue to be applicable and relevant to the problem being faced. This integrated approach has been tested over many years in Merseyside and found to be a robust approach to ever-changing problems that are well described by the management term, “wicked problems”.  相似文献   
902.
In copper based antifouling (AF) paints Cu (I) oxide was largely used as booster biocide. In this study effect of Cu (I) oxide on two marine microalgae, Tetraselmis suecica and Dunaliella tertiolecta was demonstrated. EC50 (96 hr) concentrations estimated for T. suecica and D. tertiolecta were 1.3 mg l(-1) and 1.34 mg l(-1), respectively. Copper (I) oxide induced changes in growth, chlorophyll, carbohydrate and protein contents were observed in T. suecica and D. tertiolecta. At low concentration of 0.0625 mg l(-1), 3-26% and 1-16% growth stimulation was observed in T. suecica and T. tertiolecta respectively. Increasing Cu (I) oxide concentrations proportionately decreased the carbohydrate and protein contents. This study clearly indicates the toxicity of excessive Cu (I) oxide on growth and biochemical compositions of T. suecica and D. tertiolecta.  相似文献   
903.
Biodegradation potentials of polycyclic aromatic hydrocarbons (PAHs) were determined with soil samples collected from various depths of a PAH-contaminated site and of a site nearby where PAHs were not found. Putative dioxygenase genes were amplified by a primer set specific for initial dioxygenases and identified by web-based database homology search. They were further categorized into several groups of which four dioxygenases were selected as probes for DNA hybridization. The hybridization signals according to the presence of putative dioxygenases were positively related to the extent of PAH contamination. However, the signal intensities varied depending on the probes hybridized and moreover were not consistent with PAH biodegradation activities determined by CO2 evolution. Despite widely accepted advantages of molecular biodegradation assessment, our data clearly present the variations of assessment results depending on the genetic information used and suggest that the methodology may tend to underestimate the real biodegradation capacity of a site probably due to the limited dioxygenase database available at the moment. Therefore, the molecular assessment of biodegradation potential should involve a very careful primer and probe design and an extensive microbiological examination of a site of interest to accurately delineate the biodegradation potential of the site.  相似文献   
904.
The mechanisms underlying size-assortative pairing have received considerable attention. Typically, pairing is assumed to occur at, or just prior to, the adult phase of the life cycle. However, in many invertebrates, males commence associations with juvenile females who are more than a single moult away from sexual maturity. These species are ideal to explore the importance of reproductive and survival benefits as mechanisms driving size-assortative pairing. In the Zeus bug, Phoreticovelia disparata, adult males are found riding on juvenile (fourth and fifth instar) and adult females—a behaviour that is costly for females but has survival benefits for males. Using a combination of field collections and laboratory manipulations, we show that pairing is size-assortative both within and between female age classes and that riding males are smaller than non-riding males. In a series of mating trials, we revealed that males attempt to ride any female but that their riding success is dependent on female age. We also provide the first direct evidence of female resistance to male riding attempts in P. disparata. We propose that size-assortative pairing arises through adaptations that have evolved to minimise the potential costs of sexual conflict. We suggest that the selective pressure on males to maximise survival benefits is sufficiently high that it outweighs the reproductive benefits of discriminating against fourth instar females. Finally, given that female resistance is under direct selection in juvenile females, it is likely to be the main form of selective pressure for adult females.  相似文献   
905.
Ohne Zusammenfassung Hintergrundinformation Umweltbundesamt (2007). Abschlussbericht des Forschungsprojektes „Charakterisierung endokrin vermittelter Wirkungen in Fischen: Relevante Parameter für die Entwicklung einer neuen OECD-Testmethode und in der Anwendung in der gesetzlichen Umweltrisikobewertung“ im Auftrag des Umweltbundesamtes (F?rderkennzeichen 206 67 470). Online erh?ltlich unter  相似文献   
906.
Meeting environmental limits represents the most important issue in the field of waste processing. Our primary effort consists either in eliminating hazardous emissions or in prevention of their production. However, this is not feasible in most cases therefore the so called secondary methods have to be applied. Technologies based on adsorption of hazardous compounds using activated carbon, deNOx/deDiox technologies as well as technology of catalytic filtration using a special material REMEDIA® proved itself to be very efficient. The latter technology consists in using a baghouse with bags manufactured from a special material (two layers – membrane from ePTFE and felt with bound in catalyst) called REMEDIA® which has successfully been used for removal of PCDD/F during recent period. However, it has been found that this technology can partially remove NOx as well. Based on our experience from operation industrial incineration plants it has been proved that even after more than three years' operation the activity of filtration material was not decreased and efficiency of dioxins removal from flue gas ranges from 97 to 99% (Pa?ízek et al., 2008).Based on industrial experience and new findings it has been decided to focus continuing research and development on deNOx experiments by applying SCR using the above mentioned efficient filtration material. This type of material is primarily designed for reduction of PMs and PCDD/F. Experiments with this filtration material should test possibilities for simultaneous reduction of PMs, PCDD/F and NOx. Tests are performed in MSW incineration plant utilizing new experimental unit and under standard conditions. Waste processing capacity of the incineration plant amounts to 15 t/h. Tests result in evaluation of overall reduction efficiency and negative factors that might influence the efficiency. Catalytic filtration is further compared to other types of deNOx methods.Thus we have obtained qualitatively new knowledge about this method the value of which is emphasized by full scale industrial testing.  相似文献   
907.
This report proposes a new set of guidelines for the characterization of municipal solid waste. It is based on an analysis of reference methodologies, used internationally, and a case study of Valorsul (a company that handles recovery and treatment of solid waste in the North Lisbon Metropolitan Area). In particular, the suggested guidelines present a new definition of the waste to be analysed, change the sampling unit and establish statistical standards for the results obtained. In these new guidelines, the sampling level is the waste collection vehicle and contamination and moisture are taken into consideration. Finally, focus is on the quality of the resulting data, which is essential for comparability of data between countries. These new guidelines may also be applicable outside Portugal because the methodology includes, besides municipal mixed waste, separately collected fractions of municipal waste. They are a response to the need for information concerning Portugal (e.g. Eurostat or OECD inquiries) and follow European Union municipal solid waste management policies (e.g. packaging waste recovery and recycling targets and the reduction of biodegradable waste going to landfill).  相似文献   
908.
The Clean Development Mechanism (CDM) was introduced by the Kyoto Protocol to provide a financial incentive to establish project activities in developing countries for reducing greenhouse gas emissions while also fostering sustainable development. This article shows that waste management project activities play an important role in achieving the aims of the CDM. It describes how these activities have to prove additionality, how the emission reductions must be calculated and monitored in order to be eligible and in order to lead to Certified Emission Reductions (CERs). The article further provides an analysis about the various challenges that are involved in applying the CDM scheme to waste management project activities, which require a new specific set of technical skills and regulatory standards.  相似文献   
909.
Conventional wisdom has advocated environmental auditing as a prudent part of an internal control program and one of the key tools in driving proactive efforts. As a part of risk management activities, it is often employed to protect an organization and its employees and officers from liability. Conscientious use of such audits has undoubtedly protected human health and the environment. Ironically, those who make the most consistent efforts to audit compliance and management systems, according to advocates of audit protection, may be the most vulnerable to enforcement actions and lawsuits. In this, the second part of a two-part article, we turn our attention to the likely solutions for audit protection in the current context.  相似文献   
910.
The realisation of an opto-chemical ammonia sensor suitable for personal monitoring tasks is described, comprising a cyanine dye immobilised in a microporous glass thin film. The fabrication of sensor platforms incorporating embossed grating couplers provides a compact optical design with effective waveguiding characteristics, resulting in reversible ammonia sensitivity in the 5-100 ppm range in under 2 min. Cross-sensitivity of sensor response with water and other potential interferents is considered.  相似文献   
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