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51.
Abstract

Public housing developments across the United States are being demolished, potentially increasing local concentrations of particulate matter (PM) in communities with high burdens of severe asthma. Little is known about the impact of demolition on local air quality. At three public housing developments in Chicago, IL, PM with an aerodynamic diameter <10 μm (PM10) and <2.5 μm were measured before and during high-rise demolition. Additionally, size-selective sampling and real-time monitoring were concurrently performed upwind and downwind of one demolition site. The concentration of particulates attributable to demolition was estimated after accounting for background urban air pollution. Particle microscopy was performed on a small number of samples. Substantial increases of PM10 occurred during demolition, with the magnitude of that increase varying based on sampler distance, wind direction, and averaging time. During structural demolition, local concentrations of PM10 42 m downwind of a demolition site increased 4- to 9-fold above upwind concentrations (6-hr averaging time). After adjusting for background PM10, the presence of dusty conditions was associated with a 74% increase in PM10 100 m downwind of demolition sites (24-hr averaging times). During structural demolition, short-term peaks in real-time PM10 (30-sec averaging time) occasionally exceeded 500 μg/m3. The median particle size downwind of a demolition site (17.3 μm) was significantly larger than background (3 μm). Specific activities are associated with real-time particulate measures. Microscopy did not identify asbestos or high concentrations of mold spores. In conclusion, individuals living near sites of public housing demolition are at risk for exposure to high particulate concentrations. This increase is characterized by relatively large particles and high short-term peaks in PM concentration.  相似文献   
52.
Landslides are geomorphological phenomena that affect anthropogenic and natural features on the Earth’s surface. Many previous studies have identified several factors that have contributed to landslides. Among these factors are physical characteristics, such as slope, aspect, and land cover, of Earth’s surface. Moreover, landslides can be triggered by human activities such as underground mining. This study aims to identify landslide susceptibility areas by analyzing landslide-related factors, including land subsidence triggered by underground mining. The area of interest was Kozlu, Turkey, where underground mining has been in progress for the past 100 years. Thus, to identify landslide risk zones, the multicriteria decision analysis method, together with the analytical hierarchy method, was used. The datasets included were topography, land cover, geological settings, and mining-induced land subsidence. The spatial extent of land subsidence was estimated using a previously published model. A landslide susceptibility map (LSM) was developed using a purposely developed GIS-based software. The results were compared with a terrain deformation map, which was developed in a separate study using the differential synthetic aperture radar interferometry (DInSAR) technique. The results showed a substantial correlation between the LSM and DInSAR map. Furthermore, it was found that ~?88% of the very high and high landslide risk areas coincided with location of the past landslide events. These facts suggest that the algorithm and data sources used were sufficient to produce a sufficiently accurate LSM, which may be used for various purposes such as urban planning.  相似文献   
53.
In recent years, due to the rapid increase in population density, building density and energy consumption, the outdoor air quality has deteriorated in the crowded urban areas of Turkey. Elaz?? city, which is located in the east Anatolia region of Turkey, is also influenced by air pollutants. In the present study, relationship between monitored air pollutant concentrations such as SO2 and the total suspended particles (TSP) data and meteorological factors such as wind speed, temperature, relative humidity, solar radiation and atmospheric pressure was investigated in months of October, November, December, January, February, and March during the period of 3 years (2003, 2004 and 2005) for Elaz?? city. According to the results of linear and non-linear regression analysis, it was found that there is a moderate and weak level of relation between the air pollutant concentrations and the meteorological factors in Elaz?? city. The correlation between the previous day’s SO2, TSP concentrations and actual concentrations of these pollutants on that day was investigated and the coefficient of determination R2 was found to be 0.64 and 0.54, respectively. The statistical models of SO2 and TSP including all of meteorological parameters gave R2 of 0.20 and 0.12, respectively. Further, in order to develop this model, previous day’s SO2 and TSP concentrations were added to the equations. The new model for SO2 and TSP was improved considerably with R2?=?0.74 and 0.61, respectively.  相似文献   
54.
This study assessed land cover (LC) changes in Kahramanmara? (K.Mara?) and its environs by using multitemporal Landsat and ASTER imagery, respectively belong to 1989, 2000 and 2004. A priori defined nine land cover classes in the classification scheme were urban and built-up, forest, sparsely vegetated areas, grassland, vegetated stream beds, unvegetated stream beds, bare areas, crop fields, and water bodies. Individual classifications were employed using the combination of both unsupervised and supervised classification methods. Iterative Self Organizing Data Analysis (ISODATA) was used to reduce spectral variation in the scenes arising from complex pattern of crop fields. Maximum Likelihood classifier was used in the LC classification of the individual images. Image pairs of consecutive dates were compared by overlaying the thematic LC maps and cross-tabulating the LC statistics. Urbanization and expansion of agriculture were the major reasons for the dramatic LC conversions. The amount of conversion from crop fields to water occurred as large as 927.67 ha, accounting for 73% of the total land-to-water conversion. Conversions to agriculture have mainly been occurred from grasslands and sparsely vegetated areas as large as 1,314.95 and 1,325.84 ha, respectively. Urban coverage doubled in this period as a result of 1,443.45 ha of increase. Urban area increased in the second period from 2,920 to 3,526 ha. Conversions to agriculture occurred at high amounts. A total of 1,075.79 ha area changed from sparsely vegetated areas to crop fields. A landscape-level environmental monitoring scheme based on satellite remote sensing was proposed for effective environmental resource management.  相似文献   
55.
Information on the potential risk for soil salinity buildup can be very helpful for soil salinity management in irrigated areas. We evaluated the spatial and temporal variability of groundwater salinity (GWS) and groundwater depth (GWD), which are two of the most important indicators of soil salinity, by indicator kriging technique in a large irrigated area in northern Turkey. GWS and GWD were measured on a monthly basis from irrigation season (August 2003) to rainy season (April 2004) at 60 observation wells in the 8,187-ha irrigated area. Five indicator thresholds were used for GWS and GWD. The semivariogram for each of the thresholds for both variables was analyzed then used together with experimental data to interpolate and map the corresponding conditional cumulative distribution functions (CCDF). Risk for soil salinity buildup was greater in the irrigation season compared to that in the rainy season. The greatest risk for soil salinity buildup occurred in the eastern part of the study area, suffering from poor drainage problem due to malfunctioning drainage infrastructure, as indicated by the CCDF of GWS and GWD obtained in both seasons. It was concluded that a combination of mechanical and cultural measures should be taken in high-risk locations to avoid further salinity problems.  相似文献   
56.
Prior research analyzing surface acting—employees' regulation of emotional expressions—has mostly focused on the interactions between front‐line employees and their customers in service industries and paid very little attention to intra‐organizational relationships. With an aim to shed light on this important yet relatively unexplored area, I developed a theoretical model analyzing the antecedents and outcomes of surface acting within organizations, by drawing on the sociometer theory and self‐presentation theory frameworks. To test the model, I conducted a cross‐level field study in a sample of 65 work groups and 478 employees in two organizations, located in a large city in Northern California. I have collected the data from two sources, including employees and their supervisors who rated their performance. Results indicated that employees were more likely to engage in surface acting when their affective traits and personal goals were less congruent with work environment. Surface acting was also positively related to perceived organizational politics and self‐monitoring. As for outcomes, surface acting was positively related to emotional exhaustion and negatively to performance. I discuss limitations, implications, and future research direction. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
57.
It is well known that air pollution exerts adverse effects on health and environment. Bal?kesir located in the Marmara region (Turkey) has serious air pollution problems produced by heating in the months of winter. In this study, the effect of exposure to air pollution on hospital admission for respiratory illnesses among children and adults was examined. Epidemiological data from records of hospitals, air pollutants and meteorological data were used. During July 2005–July 2007 period, there was a total of 280,426 hospital admissions for respiratory diseases. In a population-based analysis, 9 children were admitted for asthma, 17 children for acute bronchitis, and 20 children for lower respiratory diseases out of 100 children. There was a significant increase in the hospital admissions for respiratory diseases and air pollutants from October to March. It was concluded that children living in the city suffer from respiratory diseases such as asthma, pneumonia, and lower respiratory diseases. Three factors that account for approximately 90% of total variance of hospital admissions, air pollution, and meteorology were identified by means of principal component factor analysis.  相似文献   
58.
In this study, PM10 concentrations and elemental (Al, Fe, Sc, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, Sn, Sb, Ba, Pb, and Bi) contents of particles were determined in Düzce, Turkey. The particulate matter samplings were carried out in the winter and summer seasons simultaneously in both urban and sub-urban sampling sites. The average PM10 concentration measured in the winter season was 86.4 and 27.3 μg/m3, respectively, in the urban and sub-urban sampling sites, while it was measured as 53.2 and 34.7 μg/m3 in the summer season. According to the results, it was observed that the PM10 levels and the element concentrations reached higher levels, especially at the urban sampling site, in the winter season. The positive matrix factorization model (PMF) was applied to the data set for source apportionment. Analysis with the PMF model revealed six factors for both the urban (coal combustion, traffic, oil combustion, industry, biomass combustion, and soil) and sub-urban (industry, oil combustion, traffic, road dust, soil resuspension, domestic heating) sampling sites. Loadings of grouped elements on these factors showed that the major sources of the elements in the atmosphere of Düzce were traffic, fossil fuel combustion, and metal industry-related emissions.  相似文献   
59.
Turkey is one of the world??s largest producers and exporters of table grapes. Growing social concerns over excessive pesticide use have led to farming to move from conventional to organic practices. Table grapes were collected from 99 different farms in three Aegean regions. Pesticide residues were only detected in farms using conventional agriculture practices while no pesticides were detected in grapes from farms using organic or integrated pest management. A risk assessment model indicated that lambda-cyhalothrin posed the most significant risk at conventional farms.  相似文献   
60.
Many studies have been conducted to investigate thephysicochemical behavior of pure clay minerals and predicttheir engineering performance in the field. In this study, thephysicochemical properties of an artificial mixture of differentclay minerals namely, 40-50% montmorillonite, 20-30% illite and 10-15% kaolin were investigated. The mixture was homoionized with sodium, Na+; calcium, Ca2+; andaluminum, Al3+. The engineering properties studied wereconsistency limits, sediment volume, compressibility behavior,and hydraulic conductivity. The results revealed that theliquid, plastic and shrinkage limits of soil increased withincreasing cation valence. The hydraulic conductivity of thesoil also increased with an increase in the valence of thecation at any given void ratio. Aluminum and sodium treatedclays had the highest and the lowest modified compressionindex values, respectively. Furthermore, trivalent cationsaturated clayey soil consolidates three times faster thanthat of monovalent and two times faster than that of divalent.These properties of the soils determined were, in general,similar to those of kaolinite rather than those ofmontmorillonite. The comparison of the results obtained withthe published data in the literature revealed that thephysicochemical behavior of the tested clay soil was, ingeneral, similar to that of kaolinite.  相似文献   
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