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41.
42.
The stable-carbon kinetic isotope effects (KIEs) associated with the production of methacrolein (MACR) and methyl vinyl ketone (MVK) from the reactions of isoprene with ozone and OH radicals were studied in a 25 L reaction chamber at (298±2) K and ambient pressure. The time dependence of both the stable-carbon isotope ratios and the concentrations was determined using a gas chromatography combustion isotope ratio mass spectrometry (GCC-IRMS) system. The average yields of 13C-containing MACR and MVK generated from the ozone reaction of 13C-containing isoprene differed by ?3.6‰ and ?4.5‰, respectively, from the yields for MACR and MVK containing only 12C. For MACR and MVK generated from the OH-radical oxidation of isoprene the corresponding values were ?3.8‰ and ?2.2‰, respectively. These values indicate a significant depletion in the 13C abundance of MACR and MVK upon their formation relative to isoprene’s pre-reaction 13C/12C ratio, which is supported by theoretical interpretations of the oxidation mechanism of isoprene and its 13C-substituted isotopomers. Numerical model calculations of the isoprene + O3 reaction predicted a similar depletion in 13C for both reaction products upon production. Furthermore, the model predicts mixing ratios and stable carbon delta values for isoprene, MACR, and MVK that were in agreement with the experimental results. The combined knowledge of isotope enrichment values with KIEs will reduce uncertainties in determinations of the photochemical histories of isoprene, MACR, and MVK in the troposphere. The studies presented here were conducted with using isoprene without any artificial isotope enrichment or depletion and it is therefore very likely that these results are directly applicable to the interpretation of studies of isoprene oxidation using stable carbon isotope ratio measurements.  相似文献   
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44.
Abstract

The capping of stationary source emissions of NOx in 22 states and the District of Columbia is federally mandated by the NOx SIP Call legislation with the intended purpose of reducing downwind O3 concentrations. Monitors for NO, NO2, and the reactive oxides of nitrogen into which these two compounds are converted will record data to evaluate air quality model (AQM) predictions. Guidelines for testing these models indicate the need for semicontinuous measurements as close to real time as possible but no less frequently than once per hour. The measurement uncertainty required for AQM testing must be less than ±20% (±10% for NO2) at mixing ratios of 1 ppbv and higher for NO, individual NOz component compounds, and NOy. This article is a review and discussion of different monitoring methods, some currently used in research and others used for routine monitoring. The performance of these methods is compared with the monitoring guidelines. Recommendations for advancing speciated and total NOy monitoring technology and a listing of demonstrated monitoring approaches are also presented.  相似文献   
45.
This study integrates the emotion and social influence literatures to examine how emotion recognition ability (ERA) relates to annual income. In a sample of 142 employee–peer–supervisor triads from a broad range of jobs and organizations, we find that people's level of ERA indirectly relates to how much they earn per year. The relationship between ERA and annual income is mediated sequentially through political skill and interpersonal facilitation. The results imply that emotional abilities allow people not only to process affect‐laden information effectively but also to use this information to successfully navigate the social world of organizations in the pursuit of prosperity. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
46.

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Goal Scope and Background. The European Directive on Energy Performance of Buildings which came into force 16 December 2002 will be implemented in the legislation of Member States by 4 January 2006. In addition to the aim of improving the overall energy efficiency of new buildings, large existing buildings will become a target for improvement, as soon as they undergo significant renovation. The building sector is responsible for about 40% of Europe's total end energy consumption and hence this Directive is an important step for the European Union in order that it should reach the level of saving required by the Kyoto Agreement. In this the EU is committed to reduce CO2 emissions relative to the base year of 1990 by 8 per cent, by 2010. But what will be the impact of the new Directive, how large could be the impacts of extending the obligation for energy efficiency retrofitting towards smaller buildings? Can improvement of the insulation offset or reduce the growing energy consumption from the increasing installation of cooling installations? EURIMA, the European Insulation Manufacturers Association and EuroACE, the European Alliance of Companies for Energy Efficiency in Buildings, asked Ecofys to address these questions.

Methods

The effect of the EPB Directive on the emissions associated with the heating energy consumption of the total EU 15 building stock has been examined in a model calculation, using the Built Environment Analysis Model (BEAM), which was developed by Ecofys to investigate energy saving measures in the building stock. The great complexity of the EU-15 building stock had to be simplified by examining five standard buildings with eight insulation standards, which are assigned to building age and renovation status. Furthermore, three climatic regions (cold, moderate, warm) were distinguished for the calculation of the heating energy demand. This gave a basic 210 building types for which the heating energy demand and CO2 emissions from heating were calculated according to the principles of the European Norm EN 832.

Results and Discussion

The model calculations demonstrates that the main contributor to the total heating related CO2 emissions of 725 Mt/a from the EU building stock in 2002 is the residential sector (77%) while the remaining 23% originates from non-residential buildings. In the residential sector, single-family houses represent the largest group responsible for 60% of the total CO2 emissions equivalent to 435 Mt/a.

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- The technical potential: If all retrofit measures in the scope of the Directive were realised immediately for the complete residential and non-residential building stock the overall CO2 emission savings would add up to 82 Mt/a. An additional saving potential compared to the Directive of 69 Mt/a would be created if the scope of the Directive was extended to cover retrofit measures in multi-family dwellings (200-1000m2) and non-residential buildings smaller than 1000m2 used floor space. In addition including the large group of single-family dwellings would lead to a potential for additional CO2 emission reductions compared to the Directive of 316 Mt/a.

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- Temporal mobilization of the potential: Calculations based on the building stock as it develops over time with average retrofit rates demonstrated that regulations introduced following the EPB Directive result in a CO2 emissions decrease of 34 Mt/a by the year 2010 compared to the business as usual scenario. Extending the scope of the EPB Directive to all residential buildings (including single and multi-family dwellings), the CO2 emission savings potential over the 'business as usual' scenario could be doubled to 69 Mt/a in the year 2010. This creates an additional saving potential compared to the Directive of 36 Mt/a.

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- Cooling demand: The analysis demonstrated that in warm climatic zones the cooling demand can be reduced drastically by a combination of lowering the internal heat loads and by improved insulation. With the reduction of the heat loads to a moderate level the cooling demand, e.g. of a terraced house located in Madrid, can be reduced by an additional 85% if the insulation level is improved appropriately.

Conclusions

This study demonstrates that the European Directive on Energy Performance of Buildings will have a significant impact on the CO2 emissions of the European building stock. The main saving potential lies in insulation of the existing building stock. Beyond this, CO2 emissions could, however, be greatly reduced if the scope of the Directive were to be extended to include retrofit of smaller buildings.

Recommendation and Perspective

The reductions should be seen in relation to the remaining gap of 190 Mt CO2 eq. per annum between the current emission levels of EU-15 and the target under the Kyoto-Protocol for the year 2010. The energy and industrial sector will probably contribute only a fraction of this reduction via the newly established EU emissions trading scheme and connected projects under the flexible mechanism. In addition, the traffic sector is likely to continue its growth path leading to a widening of the gap. Thus, there is likely to be considerable pressure on the EU building sector to contribute to the EU climate targets beyond what will be achieved by means of the current EPB Directive. Legislators on the EU and national level are therefore advised to take accelerated actions to tap the very significant emission reduction potentials available in the EU building stock.  相似文献   
47.
In the framework of an EU project on sustainable village development in China (SUCCESS), the natural climate resource was evaluated. Climate is seen as a potential for sustainability, an improvement of social life, agricultural production and reduction of air pollution problems. In this respect, thermal comfort conditions, microclimates and ventilation patterns were studied in seven Chinese villages and climate maps were drawn. Following planning recommendations, they can be transferred to decision-makers for their village development. In this framework, the paper presents a general methodology of urban climate mapping, carried out in China, applicable to all countries and climates.  相似文献   
48.
Polybrominated diphenyl ethers (PBDEs) are flame retardants added to a multitude of products to reduce flammability. PBDEs have been widely detected and quantified in biota and humans in many industrialised countries from the Northern Hemisphere. However data concerning the levels of these compounds in the Australian population and environment remain limited. The objectives of this study were to determine PBDE concentrations and congener profiles in Australian human milk and compare this to concentrations found in other countries. Pooled human milk samples obtained from mothers residing in 12 regions of Australia were analysed by HRGC/HRMS for 18 PBDE congeners. In total, 157 human milk samples collected in 2002 and 2003 were divided into 17 regional pools. PBDEs were detected in all pools of human milk from Australia. The mean+/-standard deviation and median summation operatorPBDE concentrations were 11.1+/-3.2 and 11.0 ng g(-1) lipid, respectively with a range of 6.1-18.7 ng g(-1) lipid. The congener profile was dominated by BDE-47 followed by BDE-99, -100, -153, -154 and -183. Regional differences were evaluated, but no trends were observed. The data suggest regional differences are likely to be small if they exist at all. The concentrations of PBDEs found in Australian human milk were lower than those reported from North America but higher than those reported from Europe and Asia. Our results suggest that the exposure pathways which contribute to the PBDE body burden in the Australian population require a better understanding in order to determine future policy regarding their use and disposal.  相似文献   
49.
Efficient environmental protection requires global, as well as regional ecological strategies. During the last decade numerous attempts at regional and global environmental protection have been made. But industrial environmental protection is still, above all, a national matter. National emission limit values and international technological standards still neglect to a large extent the regional aspects of pollution prevention. Recent normative texts (international standards, European directives) can be seen as the first step to filling this gap. They represent different evolutionary stages on the way from merely technocentric to regionally integrated environmental protection. We investigate the potential of some of these normative texts to operationalise regional environmental strategies. For this purpose we will provide a framework for evaluation centred on the following questions: ? Is the installation/project/organisation perceived as part of its specific environment? ? Can local immission standards be developed on the basis of a functional classification of ecosystems? ? Are methods of integrated ecological evaluation supported? The framework will be applied to examine the European directives on Environmental Impact Assessment and Integrated Pollution Prevention and Control and two ISO (International Standardisation Organisation) standards on Environmental Management Systems (ISO 14001 and 14004) with regard to basic requirements for operationalising integrated regional environmental protection.  相似文献   
50.
The production of compost and digestate from source-separated organic residues is well established in Europe. However, these products may be a source of pollutants when applied to soils. In order to assess this issue, composts, solid and liquid digestates from Switzerland were analyzed for heavy metals (Cd, Co, Cr, Cu, Ni, Pb and Zn) addressing factors which may influence the concentration levels: the treatment process, the composition, origin, particle size and impurity content of input materials, the season of input materials collection or the degree of organic matter degradation.Composts (n = 81) showed mean contents being at 60% or less of the legal threshold values. Solid digestates (n = 20) had 20–50% lower values for Cd, Co, Pb and Zn but similar values for Cr, Cu and Ni. Liquid digestates (n = 5) exhibited mean concentrations which were approximately twice the values measured in compost for most elements. Statistical analyses did not reveal clear relationships between influencing factors and heavy metal contents. This suggests that the contamination was rather driven by factors not addressed in the present study.According to mass balance calculations related to Switzerland, the annual loads to agricultural soils resulting from the application of compost and digestates ranged between 2% (Cd) and 22% (Pb) of total heavy metal loads. At regional scale, composts and digestates are therefore minor sources of pollution compared to manure (Co, Cu, Ni, Zn), mineral fertilizer (Cd, Cr) and aerial deposition (Pb). However, for individual fields, fertilization with compost or digestates results in higher heavy metal loads than application of equivalent nutrient inputs through manure or mineral fertilizer.  相似文献   
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