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631.
The U.S. Environmental Protection Agency (EPA) initiated the national PM2.5 Chemical Speciation Monitoring Network (CSN) in 2000 to support evaluation of long-term trends and to better quantify the impact of sources on particulate matter (PM) concentrations in the size range below 2.5 μm aerodynamic diameter (PM2.5; fine particles). The network peaked at more than 260 sites in 2005. In response to the 1999 Regional Haze Rule and the need to better understand the regional transport of PM, EPA also augmented the long-existing Interagency Monitoring of Protected Visual Environments (IMPROVE) visibility monitoring network in 2000, adding nearly 100 additional IMPROVE sites in rural Class 1 Areas across the country. Both networks measure the major chemical components of PM2.5 using historically accepted filter-based methods. Components measured by both networks include major anions, carbonaceous material, and a series of trace elements. CSN also measures ammonium and other cations directly, whereas IMPROVE estimates ammonium assuming complete neutralization of the measured sulfate and nitrate. IMPROVE also measures chloride and nitrite. In general, the field and laboratory approaches used in the two networks are similar; however, there are numerous, often subtle differences in sampling and chemical analysis methods, shipping, and quality control practices. These could potentially affect merging the two data sets when used to understand better the impact of sources on PM concentrations and the regional nature and long-range transport of PM2.5. This paper describes, for the first time in the peer-reviewed literature, these networks as they have existed since 2000, outlines differences in field and laboratory approaches, provides a summary of the analytical parameters that address data uncertainty, and summarizes major network changes since the inception of CSN.
ImplicationsTwo long-term chemical speciation particle monitoring networks have operated simultaneously in the United States since 2001, when the EPA began regular operations of its PM2.5 Chemical Speciation Monitoring Network (IMPROVE began in 1988). These networks use similar field sampling and analytical methods, but there are numerous, often subtle differences in equipment and methodologies that can affect the results. This paper describes these networks since 2000 (inception of CSN) and their differences, and summarizes the analytical parameters that address data uncertainty, providing researchers and policymakers with background information they may need (e.g., for 2018 PM2.5 designation and State Implementation Plan process; McCarthy, 2013) to assess results from each network and decide how these data sets can be mutually employed for enhanced analyses. Changes in CSN and IMPROVE that have occurred over the years also are described.  相似文献   
632.
In this article, adsorption modelling was presented to describe the sorption of textile dye, Direct Red 75 (DR75), from coloured wastewater onto the natural and modified adsorbent, Posidonia oceanica. The formulation of the double-layer model with two energy levels was based on statistical physics and theoretical considerations. Thanks to the grand canonical ensemble in statistical physics some physico-chemical parameters related to the adsorption process were introduced in the analytical model expression. Fitting results show that the dye molecules are adsorbed in parallel position to the adsorbent surface. The magnitudes of the calculated adsorption energies show that the DR75 dye is physisorbed onto Posidonia. Both Van der Waals and hydrogen interactions are implicated in the adsorption process. Despite its simplicity, the model fits a wide range of experimental data, thereby supporting the underlying data that the grafted groups facilitate the parallel anchorage of the anionic dye molecule. Thermodynamic parameters, such as adsorption energy, entropy, Gibbs free adsorption energy and internal energy were calculated according to the double-layer model. Results suggested that the DR75 adsorption onto Posidonia was a spontaneous and exothermic process.  相似文献   
633.
This study investigated the effectiveness of successive bioaugmentation, conventional bioaugmentation, and biostimulation of biodegradation of B10 in soil. In addition, the structure of the soil microbial community was assessed by polymerase chain reaction-denaturing gradient gel electrophoresis. The consortium was inoculated on the initial and the 11th day of incubation for successive bioaugmentation and only on the initial day for bioaugmentation and conventional bioaugmentation. The experiment was conducted for 32 days. The microbial consortium was identified based on sequencing of 16S rRNA gene and consisted as Pseudomonas aeruginosa, Achromobacter xylosoxidans, and Ochrobactrum intermedium. Nutrient introduction (biostimulation) promoted a positive effect on microbial populations. The results indicate that the edaphic community structure and dynamics were different according to the treatments employed. CO2 evolution demonstrated no significant difference in soil microbial activity between biostimulation and bioaugmentation treatments. The total petroleum hydrocarbon (TPH) analysis indicated a biodegradation level of 35.7 and 32.2 % for the biostimulation and successive bioaugmentation treatments, respectively. Successive bioaugmentation displayed positive effects on biodegradation, with a substantial reduction in TPH levels.  相似文献   
634.
While rural transformations are nothing new in human history, current processes of rural change occur under multiple forces at an unprecedented pace, involving profound and unexpected changes in land use and users, and rapid transformations in the metabolic patterns of rural systems. The present special section aims to shed light on current drivers and pathways of rural change by analyzing, under a common conceptual and theoretical framework, examples of new ruralities that are emerging as responses across different world regions. Within this context, this introduction presents: (1) common research questions of the six presented cases of rural change; (2) the general theoretical and methodological framework of integrated assessment of societal metabolism adopted to analyze rural systems and (3) the main contributions and conclusions that could be drawn from six context-specific case studies from Asia, Latin America and Europe.  相似文献   
635.
The blood system parameters (erythropoiesis in bone marrow, peripheral blood) of brown rat have been studied for the first time in the foothills of the Central Caucasus. Several species-specific features of these parameters have been revealed that distinguishing the brown rat from other representatives of the family Muridae.  相似文献   
636.
Microcalorimetric, gasometric, and nuclear magnetic resonance (NMR) methods have been used to evaluate heat production, gas exchange, and root membrane permeability in dandelion of different morphological forms from populations exposed to different levels of air pollution. The results show that these forms differ in the level of energy metabolism and that the form with a higher metabolic level (T. off. f. dahlstedtii) is more tolerant of air pollution with motor vehicle exhausts.  相似文献   
637.
The tsunami that struck South-east Asia on 26 December 2004 left more than 500,000 people in Aceh, Indonesia, homeless and displaced to temporary barracks and other communities. This study examines the associations between prolonged habitation in barracks and the nature of fears reported by school-age children and adolescents. In mid-2007, 30 months after the tsunami, the authors interviewed 155 child and parent dyads. Logistic regression analysis was used to compare the fears reported by children and adolescents living in barracks with those reported by their peers who were living in villages. After adjusting for demographic factors and tsunami exposure, the data reveals that children and adolescents living in barracks were three times more likely than those living in villages to report tsunami-related fears. The study demonstrates that continued residence in barracks 30 months after the tsunami is associated with higher rates of reporting tsunami-related fears, suggesting that barracks habitation has had a significant impact on the psychological experience of children and adolescents since the tsunami.  相似文献   
638.
Comparative analysis of the structure of small mammal communities has been performed in two European cities located in different biomes: Chisinau (2008?C2009) and Yaroslavl (1994?C2002). The parameters studied included abundance, species composition, similarity and difference of faunas, species diversity, and proportions of groups differing in predisposition to synanthropy. It has been found that the structure of small mammal communities in these cities depends on specific physiographic conditions of the surrounding areas and on the distinctive features of the cities themselves (their structure, age, etc.). The similarity between the faunas is accounted for by the common ecological patterns of fauna formation in the biota of urban cenoses.  相似文献   
639.
A comparative analysis of reproductive behavior has been performed in the steppe lemming (Lagurus lagurus) and narrow-skulled vole (Microtus gregalis). The results show that the species are similar in certain behavioral features indicative of the stability of mating pairs. However, in the narrow-skulled vole, unlike in the steppe lemming, mature males in olfactory tests show preference for receptive sibling females versus non-kin females. Probably, it is the absence of the incest taboo that allows the involvement of young of the year in reproduction within growing family groups and accounts for “coloniality” of the species.  相似文献   
640.
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