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11.
Farkas J Peter H Christian P Gallego Urrea JA Hassellöv M Tuoriniemi J Gustafsson S Olsson E Hylland K Thomas KV 《Environment international》2011,37(6):1057-1062
The increasing number of nanomaterial based consumer products raises concerns about their possible impact on the environment. This study provides an assessment of the effluent from a commercially available silver nanowashing machine. The washing machine released silver in its effluent at an average concentration of 11μgL(-1), as determined by inductive coupled mass spectrometry (ICP-MS). The presence of silver nanoparticles (AgNPs) was confirmed by single particle ICP-MS as well as ion selective electrode measurements and filtration techniques. Size measurements showed particles to be in the defined nanosize range, with an average size of 10nm measured with transmission electron microscopy (TEM) and 60-100nm determined with nanoparticle tracking analysis (NTA). The effluent was shown to have negative effects on a natural bacterial community as its abundance was clearly reduced when exposed to the nanowash water. If washing machines capable of producing AgNPs become a common feature of households in the future, wastewater will contain significant loadings of AgNPs which might be released into the environment. 相似文献
12.
Merete Grung Anders Ruus Tor Fredrik Holth Rajdeep Singh Sidhu Dag Øistein Eriksen Ketil Hylland 《Journal of environmental radioactivity》2009
The main effluent from oil and gas production, produced water, from some platforms in the North Sea contains elevated concentrations of 226Ra. The aim of this study was to investigate whether 226Ra in sediment would accumulate in and affect sediment-dwelling organisms. In addition, we wanted to determine if the bioavailability would be modulated by the presence of a scale inhibitor which is used during oil and gas production. Hediste diversicolor was therefore exposed to different levels of 226Ra (30–6600 Bq kg−1) in combination with scale inhibitor in the sediments in a flow through system. The levels of radioactivity in the exposures were close to levels that can be measured in proximity to oil/gas production facilities. 226Ra spiked to natural sediment partitioned into pore water and accumulated in the sediment-dwelling polychaete following a four-week exposure period. The results suggest that 226Ra did not bind strongly to sediment (low sediment:water partitioning coefficient), but it was not shown to bioaccumulate in any great extent (bioaccumulation factors of 0.019–0.022). Exposure of H. diversicolor in sediments with up to 6600 Bq kg−1226Ra had no measurable effect on the total oxyradical scavenging capacity of the organisms compared to control. So although they accumulated the alpha-emitter, the treatments did not appear to cause oxidative stress in polychaete tissues. 相似文献
13.
This article explores how science and policy interact using the Norwegian Red List 2006 as a case example. The paper draws on concepts from the sociology of science, interviews with key informants, as well as analysis of a Norwegian newspaper debate about a controversial conservation issue.The paper highlights how the relationship between science and policy can best be described as an interaction rather than simply a transmission of knowledge from one to the other. In addition, the study focuses on the active construction and communication of the science–policy relationship. Regulators, scientists and NGOs, it is argued, strategically define the relationship between science and policy as more straightforward than it really is.The paper suggests that the shaping, simplification and communication of scientific knowledge is best understood as a social process that occurs in three stages, which may overlap to varying degrees. The shaping of scientific knowledge for policy occurs first within the scientific domain. The shaping, we suggest, is the result of both the broader institutional context and a more specific micro-level social context, but it is also the outcome of requirements inherent in the genre of science communication. In the second stage, regulators and actors in the public debate redefine and simplify scientific knowledge to make it better suited to the policy arena. In the final stage, scientists, regulators and NGOs actively seek to define science as objectively true, and independent of the policy arena. By doing so, they are able to strengthen their arguments, regardless of their position on particular issues. But they also contribute to shrouding the social nature of scientific production. 相似文献
14.
Bergersen O Haarstad K 《Journal of the Air & Waste Management Association (1995)》2008,58(8):1014-1021
Hydrogen sulfide (H2S) is a major odorant in landfills. We have studied H2S production from landfill residual waste with and without sulfur-containing plaster board, including the influence of the water content in the waste. The laboratory experiments were conducted in 30-L polyethylene containers with a controlled water level. We also studied how different materials removed H2S in reactive layers on top of the waste. The organic waste produced H2S in concentrations of up to 40 parts per million (ppm) over a period of 80 days. When plaster board was added, the H2S concentration increased to 800 ppm after a lag period of approximately 40 days with a high water level, and to approximately 100 ppm after 50 days with a low water level. The methane (CH4) concentration in the initial experiment was between 5 and 70% after 80 days. The CH4 concentration in the second experiment increased to nearly 70% in the container with a high water level, slowly declining to approximately 60% between days 20 and 60. The CH4 concentrations during the experiments resembled normal landfill concentrations. Metallic filter materials were very efficient in removing H2S, whereas organic filter materials showed poor H2S removal. 相似文献
15.
Marte Lundberg Haakon Hop Ketil Eiane Bjørn Gulliksen Stig Falk-Petersen 《Marine Biology》2006,149(6):1345-1353
We studied the abundance, length-frequency distribution and body composition (lipid accumulation) of the ctenophore Mertensia ovum in Kongsfjorden, Svalbard (79°N) between May 2001 and April 2002. The highest abundances were found during summer in the outer and middle areas of the fjord, possibly caused by the concentration of advected zooplankton. Polymodal length-frequencies indicated a life span of 2 years, with 0, 1 and 2-groups being present in summer. Total lipid for a standardized animal decreased from May to August, and increased to the highest level in September. Relative lipid content was always highest in the 0-group, probably reflecting reduction of lipid levels due to increased energy costs during reproduction for the older age groups. Lipids probably are used to fuel prolonged reproduction from May to August until spawning ends by September. The overwintering age groups (0 and 1) subsequently build up lipid reserves for the next years’ spawning. 相似文献