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An attempt was undertaken in this work to characterize the imission field of the PM10 particulate matter in the Warsaw area, based on measurements coming from 11 stations located in area, and from 4 stations outside Warsaw belonging to the Voivodship Inspectorate of Environmental Protection in Warsaw. The analysis concerns the 2004-06 period. Basic descriptive statistics of the concentration were calculated, the daily (24 hrs) averaged courses were studied in the whole experimental period for the cold (Oct.-March) and warm (April-Sept.) seasons, rose diagrams of particulate matter concentration percentages and of pollution plume rate percentages were made, and an effort to visualize the spatial distribution of particulate matter over the Warsaw area was made, on the basis of PM10 particulate matter concentration values registered at the stations mentioned above. As a result of the executed analyses it was found that the existing measurement network of PM10 is insufficient for a precise recognition of the imission field. It is necessary not only to extend the network of monitoring stations, especially in the Warsaw districts located on the right bank of the Vistula River, but also to include all vital meteorological parameters and particulate matter qualitative analyses into the range of measurements. In relationship to a high level of PM10 concentrations occurring in the area of the whole city, the authors propose publicizing measurement results. The analysis of pollution plumes, which was possible only for two monitoring stations located in the northern and southern parts of the city, enabled the authors to focus on substantial causes for increased PM10 concentration in that regions.
Dust on gravel roads is reduced through the application of various dust minimization materials, most frequently calcium chloride. However, global efforts have been intensified to find new effective materials that cause the least damage to the environmental. One of them is Safecote, a new patented product. In 2008 measurements were performed on the gravel road Jusevičiai-Būdvietis-Derviniai, which was treated with calcium chloride. Experiments of particulate matter concentrations in the air, when gravel road pavement was treated with a mixture of calcium chloride and Safecote, were carried out in the summer of the same year. As the findings of the experimental investigation of particulate matter concentrations in the air show, the concentration of particulate matter on the gravel road treated with calcium chloride alone reached, on average, 1.90 mg/m³, while on that treated with the mixture was 0.40 mg/m³.
Geospatial and geostatistical analysis of particulate matter (PM10) variation in Imo State, Nigeria was carried out. The objectives of the study were to determine and analyze the variation in concentration of ambient PM10 level in Imo State, Nigeria. Air quality sampling was conducted within November 2014 and June 2015, in wet and dry seasons three times daily using Haze Dust Particulate Monitor (10μm). The mean concentration of PM10 level observed in the study varied from 5.22 - 6.63mg/m3 in wet season and 5.80 - 8.38 mg/m3 in dry season. Coefficient of variation (CV %) revealed that the variability of PM10 level ranged between little and moderate variations in both wet and dry season. Analysis of variance (ANOVA p<0.05) showed statistically significant variation in the mean PM10 level in the study locations. Box and Whisker plots confirmed variation of PM10 in the morning, afternoon and evening. The GIS plots revealed the spatial attributes of the air pollutant in the study locations. Time series plots indicate that the air pollutants fluctuated throughout the study duration. The Wind Rose suggests that the prevailing wind speed and wind directions were responsible for the dispersal migration of the air pollutant in the study area. The highest seasonal mean values were observed in Egbema and Okigwe area in both dry and wet season. The seasonal mean values recorded in the study exceeded the Nigerian National Ambient Air Quality Standards. This calls for urgent response to prevent further air quality deterioration and its negative effects on man and the environment.
As people spend most of the time in closed spaces (flats, workplaces, schools etc.), the indoor air has been researched for many years all over the world. Particulate matter (PM) is one of the most often examined pollutants in the indoor and outdoor air. The following study presents the facts about PM in closed spaces and the most often taken actions. The least known aspects related to the indoor air pollution with PM are demonstrated. The indoor space of various service and office buildings/facilities (not related to production, i.e. offices, shops, beauty parlours, restaurant kitchens, restaurants, pubs etc.) seem to be an unrecognized area in the air pollution studies. Importantly, a great number of people work in such spaces all over the world and thus spend there a large part of their lives.
Two Spitsbergen fjords, Hornsund and Kongsfjorden, are known for being under different hydrological regimes. The first is cold, separated from warm Atlantic water by East Spitsbergen Current, while Kongsfjorden is frequently penetrated by relatively warm Atlantic water. On the other hand, both are under strong influence of water discharge from glaciers and land freshwater input. During the period of observation in both fjords a dominant water mass was Surface Water, which originates mainly from glacial melt. The presence of suspended matter introduced with melt water in Surface Water is reflected by highest values of light attenuation and absorption coefficients recorded in areas close to glacier both in Hornsund and Kongsfjorden. In Hornsund the maximum light attenuation coefficient cpg(555) was 5.817 m−1 and coefficient of light absorption by particles ap(676) = 0.10 m−1. In Kongsfjorden the corresponding values were 26.5 m−1 and 0.223 m−1. In Kongsfjorden suspended matter of the size class 20–200 μm dominated over fractions smaller than 20 μm while in Hornsund dominating size fraction was 2–20 μm. The results provide an evidence of considerable range of variability of the optical properties mainly due to glacial and riverine runoff. The scale of variability of particulate matter in Kongsfjorden is bigger than in Hornsund. Most of the variability in Hornsund can be attributed to glaciers discharge and a presence of particles of mineral origin, while in Kongsfjorden the organic and mineral particles contribute almost equally to defining the optical properties of water.
In this paper, an attempt is made to characterize PM₁₀ imission field in the area of Warszawa with regard to PM content of the metals As, Cd, and Ni. Particulate matter concentration measurements were performed within this agglomeration with the use of many measuring methods, different not only in respect of the sampler operation rules, but also of the accuracy, sampling frequency, and separation of the particulate matter fractions. Since 1 October 2003, Warszawa agglomeration has had an extended measurement network consisting of 4 automatic stations and 7 manual ones. This paper attempts to estimate the influence of the prevailing meteorological conditions on PM₁₀ imission and also to determine those parameter groups that enable the best description of monthly and seasonal variability of particulate matter. The data considered in this paper were collected in 2004-08. Based on the performed analysis, it could be concluded that air quality in the area of Warszawa agglomeration is still unsatisfactory. The main cause of high PM concentration in Warszawa is the dynamic development of vehicular traffic and ever-increasing number of cars; both factors cause the PM concentration to be several times higher. The second important source of particulate matter in the Warszawa area is so-called “low emission”, occurring in the heating season, generated mainly by the processes of combustion in the communal and housing sectors. In 2004-08 the meteorological conditions prevailed 22.4% to 76.2% of the decadal variability of PM concentration in the individual months and 9.5% to 56.8% of seasonal variability. The most significant influence of the meteorological conditions was during the winter, especially in January. The regression analysis has found evidence for statistically vital relationships of PM₁₀ concentration and meteorological parameters, especially maximum air temperature, wind speed, and precipitation. Research on the chemical composition of PMs presented in this paper confirms that the target values of arsenic, cadmium, and nickel concentration in PM₁₀, determined by Directive 2004/107/WE, were not exceeded at the network stations in 2006-08 and the recorded concentration of these heavy metals were low. Analyzing the tendency of air quality changes for the last five years in the area of Warszawa, it was found that there was danger of not complying with the requirements set by the European Union. The time limit by which the member countries have to adjust the PM₁₀ concentration limits in their territories to the EU norms is June 2011.
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