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111.
Aerosol organic nitrogen over the remote Atlantic Ocean 总被引:1,自引:0,他引:1
Timothy Lesworth Alex R. Baker Timothy Jickells 《Atmospheric environment (Oxford, England : 1994)》2010,44(15):1887-1893
Water soluble organic nitrogen (WSON) has been measured in aerosols collected on three research cruises on the Atlantic Ocean from approximately 55°N to 45°S. Results are interpreted using air mass back trajectories and results for other aerosol components. WSON concentrations range from <1 to ~40 (median 5.6) nmol m?3 with significant WSON concentrations in both fine (<1 μm) and coarse mode (>1 μm) aerosol. Concentrations of WSON were highest in samples containing Saharan dust, suggesting a locally significant source associated with soil dust. More generally WSON concentrations were highest in air which had recently crossed continental areas. In the whole data set, WSON is well correlated to total soluble nitrogen and represents approximately 25% of total nitrogen. This correlation implies a significant anthropogenic contribution to the organic nitrogen. 相似文献
112.
‘Environmental cognitive stress’ a hybrid model combining environmental stress and cognitive determinants of pro-environmental behavior is explored among Australians living in contrasting ‘micro’ climates in the same river catchment system. Peoples’ climate risk perceptions are mediated by their connections to local environment, observations of environmental change and personal weather experiences. A longitudinal study randomly sampled 1,162 Hunter Valley coastal and rural residents in New South Wales. Telephone interviewers (2008) recruited lakeside homeowners ‘at risk’ of sea level rise, nearby ‘control’ residents and a comparable farming area group. Follow-up interviews (2011) located 81.5 % of the original sample. Fifty-six items based on the model asked about climate change observations, concerns, impacts and actions. Statistically significant rural–suburban and time differences were found. The rural sample was attuned to conditions affecting agricultural productivity: They worried about drought and heat, saw trees dying and changes to seasons and natural rhythms. They anticipate the impact of water scarcity, conserve water and value protecting plants and animals. Compared to higher elevation residents, lake dwellers observed marine life loss, worry about sea level rise and predict the decline of property values. Across time, all groups’ perceptions of warming indicators declined. Concerns and impacts were high and generally stayed high, as did actions related to energy use. No differences emerged in beliefs about climate warming. Climate change observations, along with concerns and actions, have important implications for the environmental cognitive stress model. Overall, dynamic changes in residents’ understandings are related to a changing policy environment, the vicissitudes of climate debates and weather experiences, including extreme swings from inundation to drought. 相似文献
113.
Sandra L. Wilson Gerrit Voordouw Virginia K. Walker 《Environmental science and pollution research international》2014,21(17):10254-10261
Economic concerns associated with the recovery of non-conventional hydrocarbon reserves include unexpected ice as well as ice-like gas hydrate formation. Antifreeze proteins (AFPs) inhibit ice growth, and experiments with fish, plant, and insect AFPs have shown promise of effective gas hydrate inhibition in lab-scale experiments. If produced on an industrial scale, AFPs could provide a more environmentally friendly alternative to kinetic inhibitors, but a large-scale production of these AFPs is not currently feasible. We believe that these difficulties could be surmounted by the production of microbial AFPs, but to date, only a few such proteins have been identified and purified, and none of these are associated with hydrocarbon reserves. Here, we have used ice-affinity and freeze-thaw stress to select microbes derived from oil and gas formation water, or produced water, as a source of anaerobic microbial communities. Ice-affinity successfully incorporated anaerobic bacteria under aerobic conditions, and the mixed culture had ice-associating properties. Under these conditions, ice-affinity selection does not result in cultivatable isolates, but similar, cultivable microbes were obtained following freeze-thaw selection under anaerobic conditions. Since these mixed cultures inhibited the growth of ice crystals, they also have the potential to inhibit hydrate growth. Overall, freeze-thaw selection provides a promising first step towards the isolation of microbes capable of the inhibition of ice and gas hydrate growth, for possible application for energy exploration and recovery at high-latitudes and in-deep, cold waters. 相似文献
114.
115.
Expert elicitations are a promising method for determining how R&D investments are likely to have an impact on technological advance in climate change energy technologies. But, expert elicitations are time consuming and resource intensive. Thus, we investigate the value of the information gained in expert elicitations. More specifically, given baseline elicitations from one study, we estimate the expected value of better information (EVBI) from revisiting and improving these assessments. We find that the EVBI is very large in comparison with the cost of performing expert elicitations. We also find that EVBI is higher on technologies with larger budgets and with net values that are not too high or too low. 相似文献
116.
The adsorption behavior of natural Jordanian zeolites with respect to Cd(2 + ), Cu(2 + ), Pb(2 + ), and Zn(2 + ) was studied in order to consider its application to purity metal finishing drinking and waste water samples under different conditions such as zeolite particle size, ionic strength and initial metal ion concentration. In the present work, a new method was developed to remove the heavy metal by using a glass column as the one that used in column chromatography and to make a comparative between the batch experiment and column experiment by using natural Jordanian zeolite as adsorbent and some heavy metals as adsorbate. The column method was used using different metal ions concentrations ranged from 5 to 20 mg/L with average particle size of zeolite ranged between 90 and 350 mum, and ionic strength ranged from 0.01 to 0.05. Atomic absorption spectrometry was used for analysis of these heavy metal ions, the results obtained in this study indicated that zeolitic tuff is an efficient ion exchanger for removing heavy metals, in particular the fine particle sizes of zeolite at pH 6, whereas, no clear effect of low ionic strength values is noticed on the removal process. Equilibrium modeling of the removal showed that the adsorption of Cd(2 + ), Cu(2 + ), Pb(2 + ), and Zn(2 + ) were fitted to Langmuir, Freundlich and Dubinin-Kaganer-Radushkevich (DKR). The sorption energy E determined in the DKR equation (9.129, 10.000, 10.541, and 11.180 kJ/mol for Zn(2 + ), Cu(2 + ), Cd(2 + ) and Pb(2 + ) respectively) which revealed the nature of the ion-exchange mechanism. 相似文献
117.
Janet A. Nestlerode Virginia D. Engle Pete Bourgeois Paul T. Heitmuller John M. Macauley Yvonne C. Allen 《Environmental monitoring and assessment》2009,150(1-4):21-29
The Environmental Protection Agency (EPA) and U.S. Geological Survey (USGS) initiated a two-year regional pilot survey in 2007 to develop, test, and validate tools and approaches to assess the condition of northern Gulf of Mexico (GOM) coastal wetlands. Sampling sites were selected from estuarine and palustrine wetland areas with herbaceous, forested, and shrub/scrub habitats delineated by the US Fish and Wildlife Service National Wetlands Inventory Status and Trends (NWI S&T) program and contained within northern GOM coastal watersheds. A multi-level, stepwise, iterative survey approach is being applied to multiple wetland classes at 100 probabilistically-selected coastal wetlands sites. Tier 1 provides information at the landscape scale about habitat inventory, land use, and environmental stressors associated with the watershed in which each wetland site is located. Tier 2, a rapid assessment conducted through a combination of office and field work, is based on best professional judgment and on-site evidence. Tier 3, an intensive site assessment, involves on-site collection of vegetation, water, and sediment samples to establish an integrated understanding of current wetland condition and validate methods and findings from Tiers 1 and 2. The results from this survey, along with other similar regional pilots from the Mid-Atlantic, West Coast, and Great Lakes Regions will contribute to a design and implementation approach for the National Wetlands Condition Assessment to be conducted by EPA’s Office of Water in 2011. 相似文献
118.
Lynton W. Baker Kenneth P. MacKay 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1190-1195
This paper is directed to environmental scientists concerned with assessing toxic air pollution downwind of hazardous waste landfills to determine whether potential health threats or exceedances of air quality standards exist. The purpose of this paper is to evaluate the performance of four air quality screening models. The emission rate of vinyl chloride from the BKK co-disposal landfill in West Covina, California is estimated. Ambient vinyl chloride concentrations are estimated using a ground level point source model, two virtual point source models, arid the simple box model with meteorological and landfill input data representative of periods when ambient monitoring was conducted. The two virtual point source models are most precise and accurate in estimating 24-hour vinyl chloride concentrations. However, the results could include compensating errors in the emission rate and dispersion calculations because the emission rate estimate could not be independently evaluated. 相似文献
119.
Robert A. Baker Sr. Robert C. Doerr 《Journal of the Air & Waste Management Association (1995)》2013,63(10):409-414
The catalytic reduction of oxides of nitrogen from leaded automobile exhaust has been demonstrated to be technically feasible. These studies made with copper-containing catalysts are based upon the reducing nature of exhaust caused by the carbon monoxide present. The reaction involves 2 CO + 2 NO → + N2 + CO2 + 178.5 Kcal. 相似文献