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221.
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The goal of the work was to investigate the concentrations of the 16 US EPA priority polycyclic aromatic hydrocarbons(PAH) bound to submicrometer particles(particulate matter, PM_1) suspended in the air of university teaching rooms and in the atmospheric air outside. Two teaching rooms were selected in two Polish cities, Gliwice, southern Poland,and Warsaw, central Poland, differing with regard to the ambient concentrations and major sources of PM and PAH. The variabilities of indoor and outdoor 24-hr concentrations of PM_1-bound PAH, the ratio(I/O) of the indoor to outdoor 24-hr concentrations of PM_1-bound PAH, probable sources of PAH and the level of the hazard from the mixture of the 16 PAH(ΣPAH) to humans at both sites were analyzed. In both Warsaw and Gliwice, the mean concentrations of PM_1-bound ΣPAH were slightly higher in the atmospheric air than in the rooms. The indoor and outdoor concentrations of individual PAH in Gliwice were correlated,in Warsaw – they were not. Most probably, the lack of the correlations in Warsaw was due to the existence of an unidentified indoor source of gaseous PAH enriching PM_1 in phenanthrene, fluorene, and pyrene. Although the ambient concentrations of PM_1-bound PAH were low compared to the ones observed earlier at both sites, they were much higher than in other urbanized European areas. However, because of low mass share of heavy PAH in ΣPAH, the various indicators of the health hazard from the 16 PAH mixture were low compared to other regions.  相似文献   
223.
Walter LS 《Disasters》1990,14(1):20-35
Various kinds of Satellites, including communications, meteorology, remote sensing and geophysics satellites, are, or may become, useful tools in disaster prevention, preparedness and relief. They already provide operational capability for storm warnings and search-and-rescue efforts. Other capabilities, such as improved flood prediction and global mobile communications during relief, are close within reach. Still others, such as earthquake prediction, require considerable research. Close cooperation and communication between space technologists and disaster-management specialists will be needed in guiding research and designing and testing satellite systems. It is hoped that the International Decade for Natural Disaster Reduction can provide a framework for such activities.  相似文献   
224.
Behavioral ecologists generally agree that animals derive benefits from familiarity with spaces that they inhabit or visit, yet site familiarity is rudimentary or lacking in most models of habitat selection. In this review, I examine evidence for the occurrence of site familiarity and its fitness benefits, describe the difficulty of measuring site familiarity, note its omission from the influential ideal free and ideal despotic models, and use a literature search to test an assumption of the ideal models that has become widespread in habitat selection theory: that animals behave without regard for site familiarity. I find little support for such “familiarity blindness” in vertebrates. Next I discuss how the study of public information has drawn attention away from site familiarity and point out that both kinds of information are likely to be important in habitat selection. I proceed to examine current models of initial settlement (exploration and settlement of prebreeders on first territories) and optional resettlement (site fidelity or dispersal by established breeders following a period of prospecting) and find that the latter include only basic forms of site familiarity. Hence, I develop the concept that an inhabited space holds a unique “private value” to an animal based on its familiarity with the space and offer a simple model for optional resettlement based on private value that generates several novel predictions, including site fidelity based on cumulative breeding site familiarity and high site fidelity among species with complex territories.  相似文献   
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Sampling for nitrogen and sulfur dioxides was initiated at several National Air Sampling Network stations in 1959 using a sampler developed for that purpose. In 1961 the Gas Sampling Network was expanded to its maximum of 49 stations. Sampling equipment and collecting solutions are supplied and chemical analyses performed by the network laboratories. Sampling and analysis procedures are described briefly. Average and maximum 24-hour concentrations of nitrogen dioxide and sulfur dioxide observed at 48 stations during 1961-1963 are presented.  相似文献   
227.
This paper is directed to those persons concerned with the relationship between blood lead levels and environmental exposures to lead. Information presented in this paper represents one of the largest collections of epidemiologica! data relating blood lead levels to environmental exposures. The observed annual average ambient air lead concentration ranged from approximately 0.5 ng Pb/m3 to 23 ng Pb/m3, while lead in soil ranged from 50-24,600 ppm. Blood lead levels of children (ages 1-9 years) are related to a host of environmental variables via regression techniques. Blood lead levels were found to be most influenced by five variables. These variables are: ambient air lead, soil lead, age of the child, dustiness of the home, and occupational status of the parents. It is concluded, based upon the results of this study, that any environmental control strategy should address both the air and the soil. Soil levels in excess of 1000 ppm lead as well as air lead levels greater than 2 jug Pb/m3, 30 day average, were found to be unacceptable.  相似文献   
228.
The final article of a series of three evaluates the in situ-remediation of TNT(trinitrotoluene)-contaminated soil from ‘Werk Tanne’. The multidisciplinary approach allows a differentiated assessment. Grading with large-scale machinery leads to a depletion of TNT for almost 90% within the first 6 months, while ADNT(amino-dinitrotoluene)-content decreases more or less steadily over 1,5 years. Grading reduces the heterogenous distribution of the contamination only slightly. Results from field-monitoring and biotest-battery indicate residual toxicities of ecotoxicological relevance and a reduced capacity for biological regeneration, in comparison with the uncontamined site. Mycorrhized plants safe-guard the site and improve the soilecological conditions. Their role in reducing lower level residual toxicity requires further investigation. There is need for future research (1) on the dynamics and mechanisms of the initial decrease of TNT followed by stagnation, (2) on the fate of the primary metabolites, (3) on long-term effects of the phytoremediation, and (4) on the establishment of the complex monitoring for routine work.  相似文献   
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Engineering projects involving hydrogeology are faced with uncertainties because the earth is heterogeneous, and typical data sets are fragmented and disparate. In theory, predictions provided by computer simulations using calibrated models constrained by geological boundaries provide answers to support management decisions, and geostatistical methods quantify safety margins. In practice, current methods are limited by the data types and models that can be included, computational demands, or simplifying assumptions. Data Fusion Modeling (DFM) removes many of the limitations and is capable of providing data integration and model calibration with quantified uncertainty for a variety of hydrological, geological, and geophysical data types and models. The benefits of DFM for waste management, water supply, and geotechnical applications are savings in time and cost through the ability to produce visual models that fill in missing data and predictive numerical models to aid management optimization. DFM has the ability to update field-scale models in real time using PC or workstation systems and is ideally suited for parallel processing implementation. DFM is a spatial state estimation and system identification methodology that uses three sources of information: measured data, physical laws, and statistical models for uncertainty in spatial heterogeneities. What is new in DFM is the solution of the causality problem in the data assimilation Kalman filter methods to achieve computational practicality. The Kalman filter is generalized by introducing information filter methods due to Bierman coupled with a Markov random field representation for spatial variation. A Bayesian penalty function is implemented with Gauss–Newton methods. This leads to a computational problem similar to numerical simulation of the partial differential equations (PDEs) of groundwater. In fact, extensions of PDE solver ideas to break down computations over space form the computational heart of DFM. State estimates and uncertainties can be computed for heterogeneous hydraulic conductivity fields in multiple geological layers from the usually sparse hydraulic conductivity data and the often more plentiful head data. Further, a system identification theory has been derived based on statistical likelihood principles. A maximum likelihood theory is provided to estimate statistical parameters such as Markov model parameters that determine the geostatistical variogram. Field-scale application of DFM at the DOE Savannah River Site is presented and compared with manual calibration. DFM calibration runs converge in less than 1 h on a Pentium Pro PC for a 3D model with more than 15,000 nodes. Run time is approximately linear with the number of nodes. Furthermore, conditional simulation is used to quantify the statistical variability in model predictions such as contaminant breakthrough curves.  相似文献   
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