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101.
In March 2012, a brownfield site in Cologne was transformed into “a green garden on red clay”, when a community garden called NeuLand (new land) was created. This paper investigates in how far NeuLand is typical for a new form of political engagement 2.0, focused on local problems at people's doorstep rather than global critiques of political systems, which finds its expression in direct actions typical for the networked society, e.g. “green flash mobs.” Its potential to provide a blueprint for imagining and enacting alternative futures and new ways for citizens to claim their “right to the city” is being assessed. NeuLand provides an experiment with new forms of (urban) commons and possibly a (re)turn to the “liveable city” to replace the current neoliberal ideal of the “entrepreneurial city” [Harvey, D., 1989. From manageralism to entrepreneuralism: the transformation of urban governance in late capitalism. Geografiska Annaler, Series B, Human Geography, 71 (1), 3–17], developing new solutions to problems of urban management and city development that extend beyond the voluntary engagement of citizens within the logic of the neoliberal “big society.” Extending the scope beyond the analysis of urban gardening projects as examples of sustainable food production, or as vehicles for fostering community cohesion, integration or social capital, the NeuLand experiment is linked to wider debates of alternative and more sustainable socio-ecological futures than those currently practised in the newly “neoliberalizing cities” of Germany.  相似文献   
102.
Combustion of hydrocarbon fuels with pure oxygen results in a different flue gas composition as combustion with air. Standard CFD spectral gas radiation models for air blown combustion are out of their validity range. The series of three articles provides a common spectral basis for the validation of new developed models. Part B of the series presents spectral measurements in the spectral range of 2.4–5.4 μm of a 70 kW turbulent natural gas flame in air blown combustion and in wet and dry oxyfuel combustion. The experimentally measured intensity spectra were compared with simulated spectra based on measured gas atmospheres. The line-by-line database HITEMP2010 and the two statistical-narrow-band models EM2C and RADCAL were used for the numerical simulation. The measured spectra showed large fluctuations due to turbulence. The up to 75% increased averaged experimental intensity compared to the simulated intensity pointed out the importance of the effect of turbulence-radiation-interaction in combustion simulations.  相似文献   
103.
The environmental psychology of research   总被引:1,自引:1,他引:0  
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104.
The feasibility of monitoring CO2 migration in a saline aquifer at a depth of about 650 m with cross-hole and surface–downhole electrical resistivity tomography (ERT) is investigated at the CO2SINK test site close to Ketzin (Germany). The permanent vertical electrical resistivity array (VERA) consists of 45 electrodes (15 in the injection well Ktzi201 and 15 in each of the two observation wells Ktzi200 and Ktzi202), successfully placed on the electrically insulated casings, in the depth range of about 590–740 m with a spacing of about 10 m. The three Ketzin wells are arranged as perpendicular triangle with distances of 50 and 100 m.First synthetic modelling studies indicate an increase of the electrical resistivity of about 200% caused by CO2 injection, corresponding to a bulk CO2 saturation of 50%, which is in good agreement with laboratory studies. Finite difference inversion of field data delivers three-dimensional resistivity distributions between the wells which are consistent with the reservoir modelling studies.To increase the limited observation area provided by the cross-hole measurements, additional surface–downhole measurements were deployed. A main CO2 migration in SE–NW direction is deduced from surface to downhole resistivity experiments.The first cross-hole time-lapse results show that the resolution and the coverage of the electrode array in the Ketzin setting are sufficient to resolve the expected resistivity changes on the characteristic length scale of the electrode array. Significant resistivity changes could be measured, however, detailed information on the CO2 plume could not be resolved yet by VERA under the existing geological circumstances.  相似文献   
105.
Results of a field experiment (please refer to Warrelmann et al. 2000a) document TNT-degradation and regeneration after the establishment of a phytoremediation. Various approaches are included in a complex monitoring system, which are conducted in the field (nitroaromatics in soil, seepage water, and plants; soil fauna; soil fungi; decomposition) as well as in the lab (a battery of 6 biotests). The data document a high heterogeneity of the TNT-contamination, a rapid initial decrease and a mediocre displacement of nitroaromatics in plants and seepage water. The initial rapid transformation of TNT to aminodinitrotoluenes ceases significantly after 3 months. Results of the biotest battery allow a sophisticated assessment of soil toxicity; the results from the soil ecological field investigations make the long-term effects of TNT-contamination likely. In a third part of the series of articles, a synopsis and judgement of the project will be delivered.  相似文献   
106.

Background and Scope

The marine shipping lanes have become the most important path for the invasion of foreign aquatic organisms. The increasing global trade results in an increase in the number of marine vessels. Without any protective measures, with every ship carrying foreign organisms the risk of biological invasions will rise.

Results

The International Martime Organization (IMO) of the United Nations developed a convention to reduce the transfer of organisms with ballast water. After the entry-into-force of this convention the fleet of the world has to be equipped with effective ballast water management technology before 2016. This article discusses potential options for action. To comply with the limit values of the ballast water convention, the current state of the art demands the use of active substances. Any decision on the approval of active substances used for ballast water treatment and the environmental impact assessment lies with the IMO. Proposed to day are UV-radiation, active chlorine, active oxygen, the creation of biocides through electrolysis and a change in gases contained in the ballast water. The technologies and the potential risks are presented.

Conclusions

Despite the introduction of an approval procedure by IMO any reliable assessment of the real risks involved in the use of biocides is impossible, as the risk assessment approaches have still to be developed. On the regulatory level, the main focus in data requirements for the risk assessment is on a comprehensive testing of the toxic potential of the biocides proposed. Strategies for the identification and evaluation of the chemical resulting from the treatment of limnic, marine and brackish water are not fully developed. An integrating assessment of risks involved in the introduction of foreign organisms versus the toxic effects of the substances used or created during treatment is still missing.  相似文献   
107.
108.
Assessments of current and future development paths require comprehensive sets of indicators covering all essential aspects. From a holistic systems point of view, most currently proposed indicator sets are incomplete and deficient. Assessments of sustainable development require a full representation of the satisfaction states of the “basic orientors” (=fundamental interests) of constituent sector systems, and of their contribution to basic orientor satisfaction of the total system. Basic orientors are value dimensions (existence, effectiveness, freedom of action, security, adaptability, coexistence) emerging from a self-organizing system's interaction with its environment, and its fundamental properties (normal environmental state, scarce resources, variety, variability, change, other systems). Basic orientors are also reflected in human emotions, societal punishment, psychological and social needs, life styles, and values emerging in self-organization of artificial life. The relative weight assigned to basic orientors of partner systems is a question of ethics. Based on these concepts, a general scheme for finding a “complete” set of indicators of viability and sustainability is derived, and it is applied to deriving a comprehensive set of indicators of sustainable development for society and its sector systems (infrastructure, economic system, social system, individual development, government, environment and resource system). The method can be applied at different levels of complexity and regional resolution. A full set of regional indicators for sustainable development is presented, a method for compact assessment of development paths using orientor stars is described, and the approach for application at the community level is outlined.  相似文献   
109.
Oral vaccination of foxes (OVF) is a powerful tool to combat rabies in wildlife, and large parts of western Europe have been freed from rabies using this tool. Nevertheless, the success of OVF, given with the number of campaigns needed to eliminate the disease, depends on many factors. This article for the first time focuses on and assesses difference in OVF with respect to the spatial setting of vaccinated areas with time. The size of the areas vaccinated with time and the size of the overlapping area of consecutively vaccinated areas are particularly considered. In order to integrate these two aspects into one single figure, an Area Index is proposed ranging between 0 and 1. A statistical analysis indicates that the number of campaigns needed for rabies elimination significantly decreases on condition that the total rabies endemic area is consecutively treated right from the beginning of oral vaccination. Hence, from an economical and environmental point of view, vaccination areas should be selected the way that guarantees an Area Index close to 1. The concept of an Area Index, as described here, is a useful tool not only in the context of OVF, but it could also be used for other control schemes against infectious diseases in wildlife.  相似文献   
110.
The effect of the spin-trap α-phenyl-N-t-butylnitrone (PBN) on the formation of fatty acid dimers induced by the anoxic microsomal metabolism of tetrachloromethane was investigated in vitro, in particular, with respect to cross-linking of arachidonic acid with a second one (C20–C20) and of arachidonic acid with docosahexaenoic acid (C20–C22). PBN exerted no effect on anaerobic tetrachloromethane metabolism but inhibited dimer formation, half-maximally at a concentration of 0.1 mmol L?1. Trichloromethyl octadecenoic acid was also found, but at levels 10-fold lower than the fatty acid dimers. The data suggest that the hepato-protective effect of PBN against tetrachloromethane-toxicity may be due to its ability to scavenge fatty acid radicals, resulting in stable, non-reactive entities, which do not undergo secondary reactions such as cross-linking. The data confirm and extend previous findings that crosslinking plays an important role in tetrachloromethane toxicity and similar cases of metabolic radical-induced toxicity.  相似文献   
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