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991.
Merce Bernardo Marti Casadesus Stanislav Karapetrovic Iñaki Heras 《Journal of Cleaner Production》2010,18(5):486-495
The objective of this paper is to analyze how internal and external audits of standardized management systems are conducted, with specific focus on the actual integration of audits performed against different management system standards. The research is based on a survey of 435 organizations registered to, at a minimum, both the ISO 9001: 2000 and ISO 14001: 2004 standards. A multivariate cluster analysis is applied in order to obtain distinctive typologies of the organizations participating in the study. The results show that the majority of organizations registered to multiple standards integrate their internal audits and are also externally audited in a similar manner. In addition, three distinct groups of organizations are detected, characterized and compared with respect to their audit conduct and integration. 相似文献
992.
Oliveira C Martins N Tavares J Pio C Cerqueira M Matos M Silva H Oliveira C Camões F 《Chemosphere》2011,83(11):1588-1596
Atmospheric aerosols of four aerodynamic size ranges were collected using high volume cascade impactors in an extremely busy roadway tunnel in Lisbon (Portugal). Dust deposited on the tunnel walls and guardrails was also collected. Average particle mass concentrations in the tunnel atmosphere were more than 30 times higher than in the outside urban background air, revealing its origins almost exclusively from fresh vehicle emissions. Most of the aerosol mass was concentrated in submicrometer fractions (65%), and polycyclic aromatic hydrocarbons (PAH) were even more concentrated in the finer particles with an average of 84% of total PAH present in sizes smaller than 0.49 μm. The most abundant PAH were methylated phenanthrenes, fluoranthene and pyrene. About 46% of the total PAH mass was attributed to lower molecular weight compounds (two and three rings), suggesting a strong influence of diesel vehicle emissions on the production of local particulate PAH. The application of diagnostic ratios confirmed the relevance of this source of PAH in the tunnel ambient air. Deposited dust presented PAH profiles similar to the coarser aerosol size range, in agreement with the predominant origin of coarser aerosol particles from soil dust resuspension and vehicle wear products. 相似文献
993.
Sustainability: characteristics and scientific roots 总被引:1,自引:0,他引:1
994.
Lindahl P Maquet A Hult M Gasparro J Marissens G González de Orduña R 《Journal of environmental radioactivity》2011,102(2):163-169
The distribution of natural radionuclides was studied in winter wheat plants collected from three sites in Belgium during 2004-2007. Activity concentrations of 40K, 226Ra, 228Ra and 228Th in organically and conventionally grown wheat, and in the corresponding soil samples, were determined using ultra low-level gamma-ray spectrometry. The observed soil-to-wheat concentration ratios were calculated for the different parts of the wheat plant (root, stem and grain) in the two agricultural systems (organic and conventional). There were large variations in radionuclide activity concentrations between the sites and fields, but no significant difference between conventionally and organically grown wheat plants was observed. 相似文献
995.
Marta Doval Miñarro Enrique González Ferradás Jonathan Barberá Rico Fernando Díaz Alonso Francisco J. Marzal Martínez Cristina Romero Trigueros 《Environmental science and pollution research international》2011,18(3):436-445
Introduction
The change in light intensity that takes place when an ambient air sample is drawn into the detection chamber of a chemiluminescence monitor generates changes in the concentrations of several species, such as NO2, NO and O3. Although this phenomenon has been known for several decades, there is still no commonly accepted approach on when or how to correct for it in NO2 and O3 readings. 相似文献996.
Josep Peñuelas Angela Ribas B.S. Gimeno Iolanda Filella 《Environmental monitoring and assessment》1999,56(2):221-224
Evaluation of visual symptoms of ozone damage was conducted in the network of bioindicator rural stations of Catalonia (NE Spain) every 14 days from May to October. Damage rates of ozone (and consequently, ozone biomonitoring capacity of bioindicators) were found to vary highly in time and space depending on the local environmental and meteorological conditions. Lower ozone damage to foliage was produced when meteorological conditions favour stomata resistance. Modulatory effects of meteorological conditions need to be considered in biomonitoring and when modeling plant ozone doses and damage. 相似文献
997.
Current brief aims to introduce the concept of safety in European industrial sectors, particularly in mechanics and machinery industry. It also highlights the importance to ensure an even level of machinery safety along the European Union, setting up the appropriate frame and procedures to keep it under control. An overview over market surveillance activities for machinery (regulations, main actors and their roles) first at Community level, and secondly an approach to one of the Member States is also introduced. 相似文献
998.
Sopheak Net Laura Nieto-Gligorovski Sašo Gligorovski Brice Temime-Rousell Stephane Barbati Yannis G. Lazarou Henri Wortham 《Atmospheric environment (Oxford, England : 1994)》2009,43(9):1683-1692
Many of the more recent studies concerning heterogeneous reactions of atmospheric interest, carry, in some cases, much more details but still follow the basic philosophy of the first pioneering studies. Therefore, in this study the accent is put on the additional complexities that arise when the aerosols of interest have more complex compositions. Hence, it is attempted to identify the products following the simultaneous ozone processing and light irradiation on particles coated with 4-phenoxyphenol in the presence of 4-carboxybenzophenone as a photosensitizer. In order to reveal a more complete picture on the fate of these aromatic compounds under controlled experimental conditions, different analytical tools such as gas chromatography coupled to mass spectrometry (GC–MS) and proton transfer reaction-mass spectrometry (PTR-MS) have been applied.Several surface bound products were identified via GC–MS and some of them (phenol, hydroquinone, catechol, 4-hydroxybenzoic acid, benzoic acid, fumaric acid, terephthalic acid, maleic acid, 1,2,4-trihydroxybenzene and 4,4′-oxydiphenol) confirmed with standards. The main volatile secondary products as identified by PTR-MS in this study were formic acid, phenol and p-benzoquinone.A reaction mechanism was proposed and density functional theory calculations were performed in order to elucidate the initial steps of the ozonolysis reaction on 4-phenoxyphenol in the presence of 4-carboxybenzophenone. 相似文献
999.
José Pereira Tom H. Misselbrook David R. Chadwick João Coutinho Henrique Trindade 《Atmospheric environment (Oxford, England : 1994)》2010,44(28):3413-3421
There is a lack of information on ammonia (NH3) emissions from cattle housing systems in Mediterranean countries, with most published data deriving from NW Europe. An investigation was carried out in NW Portugal to quantify NH3 emissions for the main types of dairy cattle buildings in Portugal, i.e. naturally ventilated buildings and outdoor concrete yards, and to derive robust emission factors (EFs) for these conditions and compare with EFs used elsewhere in Europe. Measurements were made throughout a 12-month period using the passive flux sampling method in the livestock buildings and the equilibrium concentration technique in outdoor yards.The mean NH3 emission factor for the whole housing system (buildings + outdoor yards) was 43.7 g NH3–N LU?1 day?1 and for outdoor concrete yards used by dairy cattle was 26.6 g NH3–N LU?1 day?1. Expressing NH3 emission in terms of the quantity of liquid milk produced gave similar values across the three dairy farms studied (with a mean of 2.3 kg N ton-milk?1 produced) and may have advantages when comparing different farming systems. In dairy houses with outdoor yards, NH3 emissions from the yard area contributed to 69–92% of total emissions from this housing system. Emissions were particularly important during spring and summer seasons from outdoor yards with NH3 emitted in this period accounting for about 72% of annual emissions from outdoor yards. Mean NH3 emission factors derived for this freestall housing system and outdoor concrete yards used by dairy cattle in Portugal were higher than those measured in northern Europe. In addition, values of animal N excretion estimated in this study were greater than official National standard values. If these emissions are typical for Portuguese dairy systems, then the current National inventory underestimates emissions from this source in NW of Portugal, because of the use of lower standard values of N excretion by dairy cattle. 相似文献
1000.
M. Antón M. López A. Serrano M. Bañón J.A. García 《Atmospheric environment (Oxford, England : 1994)》2010,44(24):2793-2798
In recent years, research on ozone variability has mainly focused on the analysis of its trend. Additionally some studies have analyzed the annual, seasonal and day-to-day ozone variations. However, intra-diurnal total ozone variations are notably less explored. Thus, the main objective of this paper is to analyze the diurnal variability of total ozone column (TOC) as recorded by a Brewer spectrophotometer in Madrid (Spain). The results show that about 90% of days present non-negligible diurnal variability, indicating that, in general, it should not be assumed that TOC remains constant throughout a particular day in urban areas. In addition, this variability has a notable seasonal behavior which should be considered (the spring and summer months show higher diurnal TOC variations than autumn and winter months). This pattern is likely caused by the diurnal photochemical processes in the lower troposphere related to the formation of tropospheric ozone near the earth’s surface at populated urban locations. Thus, these diurnal fluctuations in tropospheric ozone could explain part of diurnal TOC variations (between 20% and 70% depending on the mixing layer height). 相似文献