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排序方式: 共有144条查询结果,搜索用时 31 毫秒
81.
This paper offers an analysis of the implementation performance of the EU Ambient Air Quality directive in the Netherlands. It provides a systematic evaluation of the implementation of a procedural provision – the obligation to design air quality policy. It draws on original data on air quality policy measures that have been collected in 13 medium-sized Dutch municipalities. The analysis of differences in the implementation performance was performed using a novel three-dimensional conceptual framework. The findings illustrate great differences in the implementation performance between the municipalities. The focused comparison allowed establishing very precisely where the implementation performance is poor or even lacking, and which municipalities take their EU implementation task more seriously than others. Most puzzling, environmental problem pressure turned out not to act as a sufficient trigger for municipalities to take far-reaching air quality measures. In contrast to previous research, a more nuanced picture is painted when it comes to the concepts of ‘compliance’, ‘non-compliance’ and ‘over-compliance’. A careful dissection of the implementation performance based on the aspects of the conceptual framework produces hands-on recommendations to municipalities seeking to improve their air quality policy.  相似文献   
82.
This study investigated whether selenium species in wheat grains could be altered by exposure to different combinations of nitrogen (N) and sulphur (S) fertilisers in an agronomic biofortification experiment. Four Australian wheat cultivars (Mace, Janz, Emu Rock and Magenta) were grown in a glasshouse experiment and exposed to 3 mg Se kg?1 soil as selenate (SeVI). Plants were also exposed to 60 mg N kg?1 soil as urea and 20 mg S kg?1 soil as gypsum in a factorial design (N + S + Se; N + Se; S + Se; Se only). Plants were grown to maturity with grain analysed for total Se concentrations via ICP-MS and Se species determined via HPLC-ICP-MS. Grain Se concentrations ranged from 22 to 70 µg Se g?1 grain (dry mass). Selenomethionine (SeMet), Se-methylselenocystine (MeSeCys), selenohomolanthionine (SeHLan), plus a large concentration of uncharacterised Se species were found in the extracts from grains. SeMet was the major Se species identified accounting for between 9 and 24 µg Se g?1 grain. Exposure to different N and S fertiliser combinations altered the SeMet content of Mace, Janz and Emu Rock grain, but not that of Magenta. MeSeCys and SeHLan were found in far lower concentrations (<4 µg Se g?1 grain). A large component of the total grain Se was uncharacterisable (>30 % of total grain Se) in all samples. When N fertiliser was applied (with or without S), the proportion of uncharacterisable Se increased between 60 and 70 % of the total grain Se. The data presented here indicate that it is possible to alter the content of individual Se species in wheat grains via biofortification combined with manipulation of N and S fertiliser regimes. This has potential significance in alleviating or combating both Se deficiency and Se toxicity effects in humans.  相似文献   
83.
This article reviews the influence of two specific European Union (EU) laws, the Birds and Habitats Directives, on the choice of national policy instruments by Member States. Both Directives leave the choice for policy instruments to manage the sites designated under the Directives to the Member States. Using path dependency as a leading concept, this article analyses the continuity or changes in policy instruments due to the implementation of the Directives in 15 countries. This article shows that the tendency to use existing instruments to implement EU policy is limited, as in almost all countries new instruments were developed. Yet, states do tend to choose instruments from their predominant policy instrument mix and preferred implementation style to address the management requirements of the Directives. Additionally, in Central and Eastern European countries where the implementation of EU policy coincided with a process of transition to a market economy, new instruments were introduced outside the existing implementation style. The introduction of new policy instruments is the result of historical turns, domestic pressure and a shift to new modes of governance. National case studies are needed to shed more light on the interaction between EU policy and domestic factors during the process of instrument choice.  相似文献   
84.
A large number of pressurized coal gasification processes being developed propose to use venturi scrubbers for particulate removal at high pressures. Theoretical predictions based on venturi scrubber performance models indicate that particle collection efficiency will decrease severely in these high gas pressure applications.

An exploratory theoretical and experimental program was performed to study the effect of gas pressure on venturi scrubber performance. Experiments were done on a 0.47 m3/s (1000 acfm) pilot scale venturi scrubber. Particle collection performance was determined as a function of scrubber pressure drop for venturi scrubbers operating In the range of 1-10 atm total pressure. Experimental results confirmed that the particle collection efficiency of venturi scrubbers decreases for a given scrubber pressure drop as total gas pressure Is increased. To achieve the same particle collection efficiency, the pressure drop across a venturi scrubber operated at 10 atm Is about 10 times that of the same scrubber operated at 1 atm pressure.  相似文献   
85.
Discharges of coloured effluents into surface waters provide conspicuous evidence of the impact of industry on the environment. The textile industry is an obvious candidate for sources of such discharges. Conventional treatment methods appear to alleviate this situation by removing colour, however the affect on toxicity is less obvious. The objective of this study was to examine the changes in effluent toxicity during the course of two alternative wastewater treatment methods, ozonation and electrochemical oxidation, using a novel toxicity biosensor, GreenScreen EM. The biosensor is capable of measuring both general acute toxicity (cytotoxicity), and more specifically genotoxicity, that is damage to a cell's DNA structure, replication or distribution, caused by substances that may be mutagenic and/or carcinogenic. The biosensor utilises a modified strain of the brewers yeast Saccharomyces cerevisiae, incorporating a gene encoding green fluorescent protein (GFP) linked to the inducible promoter of the DNA damage responsive RAD54 gene. Upon exposure to a genotoxin, the production of GFP is up-regulated in parallel with RAD54, and the resulting cellular fluorescence provides a measure of genotoxicity. Acute toxicity is simultaneously determined by monitoring relative total growth of the cell culture during incubation. The results presented in this paper show that a reduction in colouration does not necessarily correspond to a reduction in effluent toxicity.  相似文献   
86.
Since 2002, the US Environmental Protection Agency (EPA) has been funding research on the environmental aspects of nanotechnology through its Science to Achieve Results (STAR) grants program. In total, more than $25 million has been awarded for 86 research projects on the environmental applications and implications of nanotechnology. In the applications area, grantees have produced promising results in green manufacturing, remediation, sensors, and treatment using nanotechnology and nanomaterials. Although there are many potential benefits of nanotechnology, there has also been increasing concern about the environmental and health effects of nanomaterials, and there are significant gaps in the data needed to address these concerns. Research performed by STAR grantees is beginning to address these needs.  相似文献   
87.
Abstract: Legume trees have been harvested in the Sonoyta Valley since 1975. We estimated the effects of this woodcutting along the border between Organ Pipe Cactus National Monument (U.S.A.) and Sonora, Mexico. We placed 10 × 100 m transects in ephemeral watercourses and uplands on both sides of the international boundary at different distances from the border. Mesquite and ironwood trees exhibited significantly higher damage in the Mexican sites than in the protected uplands in the United States. Damage for all the species significantly decreased 500 m from the border, with the exception of ironwood, for which damage remained high within ephemeral watercourses.  相似文献   
88.
The research monitors the changes in recycling performance indicators arising from halving the collection frequency of a kerbside newspaper collection scheme. The changes in the performance parameters are explained in terms of the underlying behavioural changes that could have occurred within the community. This interpretation is aided by a computer simulation of the kerbside recycling activity of the community. Moving from a 2-week collection to a 4-week collection did not substantially affect the number of households recycling, nor the overall weights collected. A small weight loss, however, may have occurred, from a small minority of households, unable to accommodate the extra storage demand of the new regime. Model predictions were consistent with the observed performance data. It is postulated that the scheme could withstand considerable intervention before significant behavioural changes are induced. It demonstrates that cost-cutting interventions can be undertaken without significantly compromising individual participations. The case-study also highlights the caution needed in the interpretation of the recycling performance indicators themselves.  相似文献   
89.
Environment Systems and Decisions - Sustainable innovation has gained prominence in recent years, due to the demands imposed by global competition, social pressures and the needs of consumers and...  相似文献   
90.
Abstract

Occupational injuries requiring admission to a trauma unit were examined to outline the events surrounding the injury and to examine the costs. Sixty-nine patients were admitted over a 12-month period, representing 4.30% of all work-related injuries attending the emergency department and 4.25% of all admissions to the trauma unit. Most were male (91%), working in skilled trade occupations (65%), with a mean age of 38.8 years. Personal protective equipment was used only by 46% of injured workers who should have been using it. Sixty-one percent of patients believed that their injury was preventable. Half of the injuries were to the upper limb, fall was the most frequent mechanism (25%) and the median duration of admission was 2 days. The direct hospital costs were estimated at over 300 000 GBP. Failure to use protective equipment and to follow health and safety guidelines suggests that opportunities exist for injury prevention.  相似文献   
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