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81.
82.
Natalia Moreno Mar Viana Marco Pandolfi Andrs Alastuey Xavier Querol Servando Chinchn Juan Francisco Pinto Federico Torres Juan Manuel Díez Jos Saz 《Journal of environmental management》2009,91(1):133-141
Remodelling works are frequent in harbour areas, given that they must adapt to rapidly changing market requirements. Depending on their nature (construction, demolition, etc.), these works may be carried out during long periods of time and thus exert a significant impact on the air quality at the harbours and their surroundings. The air quality at the Valencia harbour was studied during an enlargement project. Four sampling stations aimed to cover the major dust-emitting activities in the harbour. In addition, a sampling campaign was carried out to collect dust materials at their emission sources (e.g., loading and unloading of clinker and petroleum coke, as well as the enlargement works). Differences obtained between PM levels at the monitoring sites were correlated with the distance between sampling stations and enlargement works and/or harbour operations, as well as with the preferential wind direction. In all cases, the days with the highest PM_10 levels were linked to wind directions coinciding with the location of the enlargement works or the clinker and petroleum coke stocks. Classic source apportionment methodologies (PCA and CMB) were applied to the data, but their interpretation was complex due to the similar chemical signatures of PM originating from direct and fugitive emissions from stocked materials (e.g., clinker), and the enlargement works. To overcome this difficulty, a novel non-statistical approach was used to obtain quantitative estimations of the contributions from sources (petroleum coke and clinker), based on the correlation between specific PM components (e.g., carbonaceous species) and source tracers (e.g., V). Finally, a qualitative test using phenolphthalein was devised to identify the presence of clinker on the filters, which provided positive results. This novel tracer approach is thus recommended for harbour authorities. 相似文献
83.
Erkara IP Asan A Yilmaz V Pehlivan S Okten SS 《Environmental monitoring and assessment》2008,144(1-3):31-41
Alternaria and Cladosporium, known as the most allergenic spores were first collected by means of Durham gravimetric sampler from Eskisehir atmosphere from January 1, 2000 to December 31, 2001. The daily, monthly and annual variations in spores/cm(2) of Cladosporium and Alternaria were recorded. During this period, a total of 10.231 spores belonging to Cladosporium and Alternaria genera were recorded. Of these spores, 5,103 were identified in 2000 and 5,128 in 2001. While 63.09% of the total spores were those of Cladosporium, 36.91% were of Alternaria. Relationships between airborne fungal spore presence and meteorological conditions were statistically investigated. A Shapiro-Wilk test revealed that the airborne Cladosporium and Alternaria spores differed from a normal distribution. Thus, a Friedmann test was performed followed by a Pearson Correlation Analysis. The effects of rainfall, temperature and wind speed on Cladosporium and Alternaria numbers were non-significant according to the sites and months (p > 0.05), but the effects of relative humidity on Cladosporium and Alternaria numbers were significant (p < 0.01). Spore concentrations reached to their highest levels in May 2001. 相似文献
84.
Pesch R Pehlke H Jerosch K Schröder W Schlüter M 《Environmental monitoring and assessment》2008,136(1-3):313-325
In this article a concept is described in order to predict and map the occurrence of benthic communities within and near the
German Exclusive Economic Zone (EEZ) of the North Sea. The approach consists of two work steps: (1) geostatistical analysis
of abiotic measurement data and (2) calculation of benthic provinces by means of Classification and Regression Trees (CART)
and GIS-techniques. From bottom water measurements on salinity, temperature, silicate and nutrients as well as from punctual
data on grain size ranges (0–20, 20–63, 63–2,000 μ) raster maps were calculated by use of geostatistical methods. At first
the autocorrelation structure was examined and modelled with help of variogram analysis. The resulting variogram models were
then used to calculate raster maps by applying ordinary kriging procedures. After intersecting these raster maps with punctual
data on eight benthic communities a decision tree was derived to predict the occurrence of these communities within the study
area. Since such a CART tree corresponds to a hierarchically ordered set of decision rules it was applied to the geostatistically
estimated raster data to predict benthic habitats within and near the EEZ. 相似文献
85.
This study was investigated the density and monthly distribution of indoor and outdoor microfungi in six different residential houses in Tekirdag City through the exposure of Petri dishes containing Rose-Bengal Streptomycin Agar media. Samples were collected in 1-month intervals over a period of 12 months between March, 2001, and February, 2002. We used 432 Petri dishes and counted a total of 4,205 microfungi colonies, 1,790 from indoor air and 2,415 from outdoor air. As a result, 42 species belonging to 12 genera were identified. The most frequent fungal genera were Penicillium (28.61%), Cladosporium (16.08%) and Alternaria (15.98%). While Penicillium (40.61%) and Cladosporium (15.92%) were the dominant genera of indoor air, Alternaria (20.62%) and Penicillium (19.71%) were isolated most frequently from outdoor air (Table 3). Alternaria citri (10.15%) and Penicillium brevicompactum (10.15%) were found to be the most frequent among the 42 identified species. While P. brevicompactum (19.55%) and Aspergillus niger (6.37%) were the most frequent indoor species, A. citri (13.37%) and Cladosporium cladosporioides (8.20%) were the most frequent outdoor species. Linear Regression Analysis was applied to determine whether or not there was a relationship between the number of colonies of isolated fungal genera and meteorological factors during the research period. Correlations between the presence of Aspergillus and temperature, relative humidity, duration of sunny periods and agents of air pollution such as SO(2) and PM were statistically significant. No significant correlations, however, were found between other fungal genera and environmental variables. 相似文献
86.
Nevzat Damla Uğur Cevik Ali Ihsan Kobya Ahmet Celik Necati Celik 《Environmental monitoring and assessment》2010,170(1-4):457-466
The activity concentrations of 226Ra, 232Th, and 40K in lime and gypsum samples used as building materials in Turkey were measured using gamma spectrometry. The mean activity concentrations of 226Ra, 232Th, and 40K were found to be 38 ± 16, 20 ± 9, and 156 ± 54 Bq kg???1 for lime and found to be 17 ± 6, 13 ± 5, and 429 ± 24 Bq kg???1 for gypsum, respectively. The radiological hazards due to the natural radioactivity in the samples were inferred from calculations of radium equivalent activities (Raeq), indoor absorbed dose rate in the air, the annual effective dose, and gamma and alpha indices. These radiological parameters were evaluated and compared with the internationally recommended limits. The experimental mass attenuation coefficients (μ/ρ) of the samples were determined in the energy range 81–1,332 keV. The experimental mass attenuation coefficients were compared with theoretical values obtained using XCOM. It is found that the calculated values and the experimental results are in good agreement. 相似文献
87.
The objective of this research was to assess the degradation of fipronil [5-amino-1-(2,6-dichloro-alpha,alpha,alpha -trifluoro-p-tolyl)-4-trifluoromethylsulfinylpyrazole-3-carbonitrile] in soils from sugar cane fields in Northeastern Brazil. Degradation experiments were carried out under laboratory conditions (controlled temperature and in the dark), where sterile and non-sterile soils (Ustoxs) were incubated [under moisture content of 55% of the water holding capacity (WHC)] and analyzed for fipronil disappearance and metabolite formation. Microbial communities present in the soil degrade fipronil. However, biodegradation seems to be dependent on the bioavailability of the fipronil and the half-life according to the zero-order model. Fipronil degradation rate appeared to be biphasic. Degradation fipronil ranged from 83 days (initial concentration = 978 ng g(-1); short-term experiment) to 200 days (initial concentration = 689 ng g(-1); long-term experiment). This an initial slower rate followed by a faster rate after 90 days of incubation may lead to shorter half-life than that calculated with the zero-order model. The sulfone derivative (an oxidation product) was the predominant metabolite, but the sulfide (a reduction product) and amide (a hydrolysis product) derivatives were also formed under non-sterile conditions after 120 days of incubation. The metabolites underwent further biodegradation, particularly the sulfone derivative. Bioavailability appears to affect fipronil degradation in soils with an effective capacity to adsorb fipronil (such as Ustoxs), while redox potential was important for the formation of metabolites. Despite the fine texture, more aerobic sites were present, thus favoring the formation of the sulfone metabolite over that of the sulfide metabolite. Therefore, microaggregation of Ustoxs, with high clay content, played a very important role in determining the types of metabolites formed. 相似文献
88.
89.
Helena M?kinen Kalevi Nieminen Susanna M?ki Sirkku Siiskonen 《International journal of occupational safety and ergonomics》2008,14(1):19-28
High temperature alkaline chemical liquids have caused injuries and hazardous situations in Finnish pulp manufacturing mills. There are no requirements and/or test method standards concerning protection against high temperature alkaline chemical splashes. This paper describes the test method development process to test and identify materials appropriate for hot liquid chemical hazard protection. In the first phase, the liquid was spilled through a stainless steel funnel and the protection performance was evaluated using a polyvinyl chloride (PVC) film under the test material. After several tentative improvements, a graphite crucible was used for heating and spilling the chemical, and a copper-coated K-type thermometer with 4 independent measuring areas was designed to measure the temperature under the material samples. The thermometer was designed to respond quickly so that peak temperatures could be measured. The main problem was to keep the spilled amount of chemical constant, which unfortunately resulted in significant variability in data. 相似文献
90.
Yasundo?KurataEmail author Yusaku?Ono Yoshiro?Ono 《Journal of Material Cycles and Waste Management》2008,10(2):144-152
The concentrations of 41 phenols in leachates from 38 municipal solid waste (MSW) landfill sites in Japan were measured. The
main phenols detected in leachates were phenol, three cresols, 4-tert-butylphenol, 4-tertoctylphenol, 4-nonylphenol, bisphenol
A, and some chlorophenols. The concentration levels of phenols were affected by the pH values of the leachates and the different
types of landfill waste. The origins of phenol and p-cresol were considered to be incineration residues, and the major origin of 4-tert-butylphenol, bisphenol A, and 2,4,6-trichlorophenol
was considered to be solidified fly ash. In contrast, the major origins of 4-tert-octylphenol and 4-nonylphenol were considered
to be incombustibles. The discharge of leachates to the environment around MSW landfill sites without water treatment facilities
can cause environmental pollution by phenols. In particular, the disposal of incineration residues including solidified fly
ash and the codisposal of solidified fly ash and incombustibles might raise the possibility of environmental pollution. Moreover,
the discharge of leachates at pH values of 9.8 or more could pollute the water environment with phenol. However, phenol, 4-nonylphenol,
and bisphenol A can be removed to below the con centration levels that impact the environment around landfill sites by a series
of conventional water treatment processes. 相似文献