Analysis of the effects of combustion emissions and Santa Ana winds on ambient ozone during the October 2007 southern California wildfires

Combustion emissions and strong Santa Ana winds had pronounced effects on patterns and levels of ambient ozone (O₃) in southern California during the extensive wildland fires of October 2007. These changes are described in detail for a rural receptor site, the Santa Margarita Ecological Reserve, located among large fires in San Diego and Orange counties. In addition, O₃ changes are also described for several other air quality monitoring sites in the general area of the fires. During the first phase of the fires, strong, dry and hot northeasterly Santa Ana winds brought into the area clean continental air masses, which resulted in minimal diurnal O₃ fluctuations and a 72-h average concentration of 36.8 ppb. During the second phase of the fires, without Santa Ana winds present and air filled with smoke, daytime O₃ concentrations steadily increased and reached 95.2 ppb while the lowest nighttime levels returned to ～0 ppb. During that period the 8-h daytime average O₃ concentration reached 78.3 ppb, which exceeded the federal standard of 75 ppb. After six days of fires, O₃ diurnal concentrations returned to pre-fire patterns and levels.     

The content of butyl- and phenyltin derivatives in the sediment from the Port of Gdansk

Harbor sediments containing large deposits of organotin compounds constitute a potential threat to the marine environment. Samples of harbor sediments were collected twice in the years 2003 and 2005 from the following locations: Zió?kowskiego, Siarkowe, Wi?lane, Weglowe, Chemików and Paliw P?ynnych Quays. The cores of 25cm length sliced into 2- and 5-cm segments were analyzed. After drying and homogenization, samples were split into two granulometric fractions, i.e. <2.00 and <0.063mm. The dominant fraction in whole sediment, i.e. fraction grain diameter <2.00mm, was sand (grain diameter 2.00-0.063mm). However, the highest concentrations of butyltin (BT) and phenyltin (PT) compounds were found in the fine sediment fraction. The mean values of tributyltin (TBT), dibutyltin (DBT) and monobutyltin (MBT) in the analyzed samples in the <2.00mm fraction were 2144.9, 434.7 and 148.1ngSng(-1)d.w., respectively, while the corresponding mean values in the <0.063mm fraction were 6556.4, 1593.7 and 450.0ngSng(-1)d.w. The mean concentrations of monophenyltin (MPhT) have been estimated at 29.0 and 49.9ngSng(-1)d.w. for the <2.00 and <0.063mm fraction sizes, respectively. The estimated content levels of diphenyltin (DPhT) and triphenyltin (TPhT) were in most cases below the detection limit of the applied method. The sediment cores collected from the locations characterized by high industrialization and intense exploitation (Wi?lane, Weglowe Quays) contained the highest concentrations of BT and PT.     

Effects of zero-valent iron (Fe0) and temperature on the transformation of DDT and its metabolites in lake sediment

Zero-valent iron improves the transformation of DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane] and its metabolites in aged and highly contaminated lake sediment under biotic conditions. The addition of Fe0 has a strong effect on transformation rates at 22 degrees C and 9 degrees C, the most enhanced degradation being obtained for DDT and DDOH [2,2-bis(p-chlorophenyl)ethanol]. At 22 degrees C and 10 weeks' incubation, the DDT concentration is reduced from 2.75 micromol g(-1) (974 mg kg(-1)) to 0.98 micromol g(-1) (346 mg kg(-1)) and 1.98 micromol g(-1) (702 mg kg(-1)) in samples with and without the addition of iron, respectively. After 40 weeks' incubation these concentrations have further decreased to 0.19 micromol g(-1) (66 mg kg(-1)) and 0.74 micromol g(-1) (264 mg kg(-1)).There is no significant transformation of any of the compounds at 9 degrees C without the addition of Fe0. In the presence of iron, however, DDT is reduced to 1.25 micromol g(-1) (442 mg kg(-1)) within 40 weeks' incubation. This study demonstrates the ability of adapted microorganisms to transform DDT under elevated temperatures in original, aged sediments, and also the stimulating effect of zero-valent iron, which is significant even at low temperatures.     

Geophysical methods in radon risk studies

The results of the studies presented in the paper have shown that in the Upper Silesian Region in Poland, radon indoor concentration levels depend first of all on the geological structure of the subsurface layers. The essential factors influencing radon migration ability are the mining-induced transformations of a rock mass. In some cases, significant variations of radon potential have been found at sites featuring similar geological structures and experiencing comparable mining effects. To find out the causes of these variations, studies involving geophysical methods such as electrical resistivity profiling (PE) and electrical resisitivity sounding (VES) were used. These studies have shown that the measurements made using the electrical resistivity method can be helpful in evaluating radon potential of both the tectonically disturbed areas and the mining-transformed ones.     

Mercury in wild mushrooms and underlying soil substrate from the great lakes land in Poland

Fifteen species of wild mushrooms and underlying soil samples collected in a virgin landscape of Augustowska Forest in northeastern Poland in 1997-98 were analyzed for total mercury to evaluate the status of contamination and usefulness of higher mushrooms as possible bioindicators of mercury pollution. Among the 15 species analyzed, Pinewood King Bolete, Scaly Tooth and King Bolete showed relatively high bioconcentration factors (BCF: dry-weight normalized concentrations of mercury in mushrooms relative to concentrations in soil) for mercury, which varied between 69 and 110. These three species were also characterized by great concentrations of total mercury in caps (between 2,000 +/- 800 and 2,300 +/- 1,100 ng g-1 dry wt) and stalks (between 850 +/- 390 and 1,000 +/- 500 ng g-1 dry wt.). Species such as Red-hot Milk Cap, Poison Pax and Common Chantherelle had mercury BCFs of less than 1, while Gipsy Bolete, Orange Birch Bolete, Brown Scaber Stalk, Variegated Bolete, Sandy Knight-cap and Yellow-cracking Bolete were weak or moderate mercury accumulators with BCFs between 1 and 40. Concentrations of mercury in mushrooms were greater than the tolerance limits suggested for mercury in plant foods.     

An Investigation into the Influence of Filler Silanization Conditions on Mechanical and Thermal Parameters of Epoxy Resin-Fly Ash Composites

The insulation material of electronic devices should offers high thermal conductivity whilst retaining suitable mechanical properties. Epoxy resin is an example of a material that is commonly used by industry for electronic insulation, despite the fact that neither the thermal conductivity nor the mechanical properties are particularly satisfying. These properties can be enhanced by incorporating filler, with silica flour representing the most popular filler. An economically appealing solution is to replace silica flour with fly ash as filler material, however it must be remembered that compatibility of fly ash and epoxy resin is not ideal. In order to improve the coupling between these two materials, fly ash particles covered with [3-(2-Aminoethylamino)propyl]trimethoxysilane were obtained with six different conditions of the silanization process, where the amount of silane, the temperature and the time of the reaction were changed. The presence of the silane layer was confirmed via Fourier Transform Infrared Spectroscopy, Thermogravimetric Analysis and Scanning Electron Microscopy. The mechanical properties, including tensile strength, Young Modulus and fracture toughness, as well as the thermal conductivity of the final samples were investigated. In the case of composites with silanized fillers, all of the mechanical properties were improved, and an enhancement of thermal conductivity was observed for several composites. Moreover, the differences in coupling between the silanized fly ash and the untreated fly ash, and the epoxy matrix were precisely recorded by means of SEM. The presented studies confirm that an effective silanization process can significantly improve the properties of composites, while also verifying the usefulness of waste material. The results highlight that fly ash may be utilized to create a more economically affordable insulation material.     

Primary sludge stabilisation with calcium hydroxide

We studied the effect of the addition of calcium hydroxide to primary raw sludges. Calcium hydroxide enhances ammonia release as well as proteins and fats hydrolysis from the sludge organic material during stabilisation process. Changes in the molecular composition of the sludge extractable lipids caused by calcium hydroxide suspension, analysed using gas chromatography interfaced to mass spectrometry detector, are discussed. Calcium hydroxide treatment selectively removes fatty acids from the sludge lipids, while it has little effect on removal and molecular assemblage of the stanol and sterol compounds during sludge stabilisation. Biogenic n-alkanes are minor components in the sludge lipids.     

Monitoring nutrient transport in large rivers

The problem of estimating nutrient transport in large rivers and the uncertainty of such load estimates was studied both empirically and theoretically. In the empirical part of the study, time series of data from the Rhine, Meuse, Vistula and Oder Rivers were examined. The results of this data analysis justify the use of linear interpolation to estimate concentrations prevailing between sampling occasions. A special study of the spatial variation of concentrations within different cross-sections of the Vistula river showed that such variation can contribute substantially to the uncertainty of load estimates. In general, however, sampling at one point in the cross-section did not result in biased load estimates. In the theoretical part of the study, simple ARMA (autoregressive-moving average) models were used to derive generally applicable formulas for the expected mean square error of load estimates based on serially dependent concentration data. These formulas were then used to estimate the uncertainty of calculated nutrient loads in the Rhine and the Vistula, respectively.     

The separation of catalyst after photocatalytic reactions conducted in the presence of TiO2/FeCl3/UV

One of the problems connected with wastewater treatment by the photocatalytic method in the presence of TiO2 suspension is necessity of the later catalyst separation. The method proposed by us for this purpose, consists in the usage of coagulation of TiO2 suspension with the aid of FeCl3, particularly in the cases when addition of the salt is used in order to intensification of the photocatalytic process. The effects of the TiO2 separation were studied from the mixtures, after photocatalytic Acid Orange 7 degradation, with dosage of FeCl3 at different stages of the process. The coagulation was carried out at different pH values as well as different FeCl3 concentrations. It was stated that nearly 100% of separation and simultaneously, nearly 100% of decolouration of the examined Acid Orange 7 solutions after their illumination in the presence of TiO2/FeCl3 and coagulation which was produced only by increasing of pH of the obtained mixtures, were nearly possible.