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861.
Hollamby S Afema-Azikuru J Waigo S Cameron K Gandolf AR Norris A Sikarskie JG 《Environmental monitoring and assessment》2006,118(1-3):13-20
An animal’s suitability as a biomonitor of environmental change can be determined by biological, reproductive and ecological
characteristics determined at the class, order and species level. The animal’s habitat where the research is to be performed
and the form, function and structure of the environmental change being studied within that habitat also determines suitability.
Non-threatened populations of large, non-migratory, long-lived, seasonally-breeding tertiary avian predators, whose dietary
preferences are narrow and known, can be useful as monitors of environmental chemical contaminants. If chemicals are being
monitored, a quantifiable endpoint effect must be demonstrated in the species, or a similar species under experimental laboratory
conditions. Logistical and economic issues as well as public and regulatory authority acceptance should also be considered
when assessing the suitability of a species as a biomonitor. 相似文献
862.
Vincent JH 《Journal of environmental monitoring : JEM》2006,8(1):53-62
In 2002 the Comité Européen Normalisation (CEN) published its document Workplace atmospheres-assessment of performance of instruments for measurement of airborne particle concentrations (EN 13205) that describes a standard protocol by which to carry out the testing and validation of personal aerosol samplers of the type widely used for occupational aerosol exposure assessment. It emerged from more than a decade of discussion and a large body of research experience involving several laboratories. The protocol that is described, however, still poses significant technical and economic challenges, not least because it involves laborious-and hence costly-procedures in large, specialized wind tunnel facilities. More recent research has identified a number of areas by which the protocol may be improved and made more accessible to testing laboratories, including a set of validated aerosol sampler scaling laws, a better understanding of the reduced role of the bluff body of the wearer on sampler performance, and the availability of new options for rapid sampler testing methods. Taking these into account, a dummy new protocol is offered for discussion. 相似文献
863.
Charlton AJ Donarski JA Jones SA May BD Clive Thompson K 《Journal of environmental monitoring : JEM》2006,8(11):1106-1110
The detection of trace levels of a range of organic contaminants (including pesticides, toxins and an explosive) in potable water, using cryoprobe NMR spectroscopy with limited sample preparation and rapid acquisition times, is described. Emphasis is placed on the applicability of NMR spectroscopy for use in emergency scenarios as the unbiased nature of the technique facilitates the detection and characterization of unknown compounds at levels as low as 50 microg L(-1). 相似文献
864.
Kuyukina MS Ivshina IB Makarov SO Litvinenko LV Cunningham CJ Philp JC 《Environment international》2005,31(2):155-161
Microbially produced biosurfactants were studied to enhance crude oil desorption and mobilization in model soil column systems. The ability of biosurfactants from Rhodococcus ruber to remove the oil from the soil core was 1.4-2.3 times greater than that of a synthetic surfactant of suitable properties, Tween 60. Biosurfactant-enhanced oil mobilization was temperature-related, and it was slower at 15 degrees C than at 22-28 degrees C. Mathematical modelling using a one-dimensional filtration model was applied to simulate the process of oil penetration through a soil column in the presence of (bio)surfactants. A strong positive correlation (R(2)=0.99) was found between surfactant penetration through oil-contaminated soil and oil removal activity. Biosurfactant was less adsorbed to soil components than synthetic surfactant, thus rapidly penetrating through the soil column and effectively removing 65-82% of crude oil. Chemical analysis showed that crude oil removed by biosurfactant contained a lower proportion of high-molecular-weight paraffins and asphaltenes, the most nonbiodegradable compounds, compared to initial oil composition. This result suggests that oil mobilized by biosurfactants could be easily biodegraded by soil bacteria. Rhodococcus biosurfactants can be used for in situ remediation of oil-contaminated soils. 相似文献
865.
Modeling the Spatially Varying Water Balance Processes in a Semiarid Mountainous Watershed of Idaho1
Benjamin T. Stratton Venakataramana Sridhar Molly M. Gribb James P. McNamara Balaji Narasimhan 《Journal of the American Water Resources Association》2009,45(6):1390-1408
Stratton, Benjamin T., Venakataramana Sridhar, Molly M. Gribb, James P. McNamara, and Balaji Narasimhan, 2009. Modeling the Spatially Varying Water Balance Processes in a Semiarid Mountainous Watershed of Idaho. Journal of the American Water Resources Association (JAWRA) 45(6):1390‐1408. Abstract: The distributed Soil Water Assessment Tool (SWAT) hydrologic model was applied to a research watershed, the Dry Creek Experimental Watershed, near Boise Idaho to investigate its water balance components both temporally and spatially. Calibrating and validating SWAT is necessary to enable our understanding of the water balance components in this semiarid watershed. Daily streamflow data from four streamflow gages were used for calibration and validation of the model. Monthly estimates of streamflow during the calibration phase by SWAT produced satisfactory results with a Nash Sutcliffe coefficient of model efficiency 0.79. Since it is a continuous simulation model, as opposed to an event‐based model, it demonstrated the limited ability in capturing both streamflow and soil moisture for selected rain‐on‐snow (ROS) events during the validation period between 2005 and 2007. Especially, soil moisture was generally underestimated compared with observations from two monitoring pits. However, our implementation of SWAT showed that seasonal and annual water balance partitioning of precipitation into evapotranspiration, streamflow, soil moisture, and drainage was not only possible but closely followed the trends of a typical semiarid watershed in the intermountain west. This study highlights the necessity for better techniques to precisely identify and drive the model with commonly observed climatic inversion‐related snowmelt or ROS weather events. Estimation of key parameters pertaining to soil (e.g., available water content and saturated hydraulic conductivity), snow (e.g., lapse rates, melting), and vegetation (e.g., leaf area index and maximum canopy index) using additional field observations in the watershed is critical for better prediction. 相似文献
866.
Michael J. Truex James M. Gillie Jefferey G. Powers Kira P. Lynch 《补救:环境净化治理成本、技术与工艺杂志》2009,19(2):7-17
The East Gate Disposal Yard (EGDY) at Fort Lewis is the source of a large trichloroethene (TCE) plume at this military installation. Source reduction using thermal treatment was applied using electrical resistance heating. A total of about 5,800 kg of TCE‐equivalent volatile organic compounds (VOCs; TCE and dichloroethene) was extracted during thermal treatment of the three zones selected for source reduction. Pretreatment groundwater TCE concentrations were measured up to 100 ppm. Posttreatment groundwater TCE concentrations within the treatment zones averaged less than 100 ppb. Posttreatment soil TCE concentrations decreased by over 96 percent compared to pretreatment soil concentrations. The overall contaminant flux from EGDY was reduced by an estimated 60 to 90 percent by the source reduction effort. The traditional and new techniques for site characterization and remediation performance monitoring applied at EGDY provide insight for installing, operating, monitoring, and assessing thermal treatment. © 2009 Wiley Periodicals, Inc. 相似文献
867.
James T. Wassell 《Safety Science》2009,47(8):1049-1055
This is a systematic review of literature published since 1992, to determine the effectiveness of interventions in preventing workplace violence and to suggest interventions that need further evaluation research. The health care industry is the topic of 54% of the papers, the retail industry is the topic of 11% of the papers, and the remaining papers address the workplace in general or other situations. This finding drives the organization of this review: the first group of papers discussed in this review evaluates interventions to prevent workplace violence in the retail industry – mostly to prevent robbery and violence to retail workers. Singly or in combination, environmental designs in the retail industry, such as increased lighting to improve visibility and a limited cash-handling policy, can make workers safer, but more research is needed to overcome the barriers to implementation of environmental designs, especially in small businesses. The second group of papers in this review is about interventions to prevent violence to health care workers – mostly training and techniques of dealing with combative patients. Training health care workers to better cope with violent patients and to avoid injury is becoming standard practice, but research is needed to identify specific aspects of training and patient management programs that are most effective. 相似文献
868.
Alastair Smith Christopher James Richard Jones Paul Langston Edward Lester John Drury 《Safety Science》2009,47(3):395-404
This paper highlights the growing need for a realistic crowd simulation in the design of large venues such as concert halls and stadia. A discrete element method (DEM) technique for modelling crowd dynamics has been developed that represents each person within the model as 3 overlapping circles, a position, orientation and velocity in 2D. Contact forces between elements are included in the model as well as psychological forces, motive forces and moments. The motion of each person is then modelled in a Newtonian manner with a numerical integration time-stepping scheme. The model has been shown previously to work well in predicting egress. In this paper the predicted model behaviour is compared to actual video footage shot at various locations around University Park Campus, Nottingham. It did not match well to the video footage when people are moving towards each other, as in cases of contra-flow on a walkway. In order to improve the model, a general algorithm for ‘avoidance’ was included which appeared to make the model significantly more realistic in these cases. The paper also shows areas for further potential development, such as incorporating people into associative groups such as family or friends. 相似文献
869.
Investigators monitoring air quality at the World Trade Center, after the September 11th attacks, found extremely high levels
of volatile organic chemicals as well as unusual species that had never been seen before in structure fires. Data collected
by the U.S. Environmental Protection Agency indicate striking spikes in levels of benzene, styrene, and several other products
of combustion. These spikes occurred on specific dates in October and November 2001, and February 2002. Additionally, data
collected by researchers at the University of California Davis showed similar spikes in the levels of sulfur and silicon compounds,
and certain metals, in aerosols. To better explain these data, as well as the unusual detection of 1,3-diphenylpropane, the
presence of energetic nanocomposites in the pile at Ground Zero is hypothesized. 相似文献
870.
Small-scale mining in China: Assessing recent advances in the policy and regulatory framework 总被引:1,自引:0,他引:1
This paper explores the background of a proposed revision to the Mineral Resources Law of China, why and how the law was amended in the past, its salient features and objectives. Of equal importance is an analysis of how this national law, with its attendant regulations and policies, formed the basis for the growth and continued development of China's small-scale mining industry. The Xiaoqingling Gold Mountain case study is shown to justify the necessity and feasibility for formalizing and consolidating small-scale mines in China, and to some extent, the success of the nation-wide ASM resource consolidation policy at a local level. 相似文献