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Concentrations of sulphate ions and particle size distributions were measured in the marine boundary layer using a ten-cascade Berner impactor at Hel between December 1997 and March 1998, and with a filter packin Gdynia from February to May 2001. In the marine boundary layer over the Hel Peninsula the presence of natural sea-salt and non-sea-salt sulphate ions (nssSO4 2−) was confirmed in the aerosols. The nssSO4 were present in all size ranges only in December 1997 and in the first half of January 1998, making up an average of 83.7±2.4% of the total sulphate content. In the other winter months, nssSO4 2− were recorded only in aerosols of diameters from 0.4 to 1.5 μm, and their average contribution dropped by over 20%. The extended growing season in the Southern Baltic resulted in the formation of fine particles that appeared in the marine boundary layer in early winter. At that time the proportion of nssSO4 2− in ultra-fine particles ranged from 75.7% to 100%. The concentration of nssSO4 2−, which varied from 0.8 to 2.3 nmol m−3 in particles < 0.4 μm in size probably constituted the natural background aerosol population in the relatively clean coastal environment of the Southern Baltic Sea. In the coastal urbanised area of Gdynia, the sulphate concentration in aerosols was higher than at Hel (av. 75.3 nmol m−3) but the proportion of nssSO4 was low, of the order of 24%. Sea salt was then the dominant source of sulphate.
Aim of study. To find correlation between the umbilical serum cord magnesium concentration in a group of newborns without antenatal exposition to magnesium sulphate and the neonatal outcome as well as to compare the neonatal outcome of babies with maternal magnesium sulphate treatment. Results. In a group of 82 newborns (31-34 GA; birth body weight <1500 g) the umbilical cord serum magnesium concentrations was assayed. Three subgroups of neonates were set apart: first group (N) with a normal magnesium level (n=28), the second group (n=19) with magnesium concentration <0.75 mmol/dl (D), and the third group (Mg) consisting of 35 newborn antenatally exposed to magnesium sulphate. These groups were similar (no statistical significances) in terms of birth body weight, gestational age, Apgar score and umbilical blood pH. Gradual decrease in magnesium concentration in relation to increase of gestational age was observed. In groups: D, N, Mg, gradual reduction of hospitalization time (p<0.05), risk of death, time of respiratory support, time of oxygen therapy, rate of bronchopulmonary dysplasia, periventricular leucomalation (p<0.05) were observed respectively. Likewise, a rate of serious neurological complication (IVH/ PVL) in group D was higher in comparison to groups N and Mg (although without statistical sig-nificances). Conclusion. Our results confirm that umbilical cord magnesium concentration in VLBW neonates have an influence on neonatal outcome. Although it is premature to recommend ordering maternal magnesium sulphate treatment to improve neonatal outcome, in our opinion the data presented here should at least induce magnesium concentration monitoring in pregnant women and magnesium deficiency correction.
The purpose of this work was to assess development of the quality of surface water in the Svatava River in the Czech Republic from 1997 to 2008. Parameters typical for pollution as a result of mining activities (SO 2-4 , Fe, Mn) were monitored, as well as select heavy metals (Pb and Cd). A falling tendency in the values of annual averages of all the monitored indicators in all profiles is apparent. The least polluted water is in the profiles Hranice and Kraslice on the upper course of the Svatava River. Conversely, the most polluted water is in the Sokolov profile, in front of the site where the Svatava River flows into the Ohře. This applies to all the monitored indicators of the Sokolov profile that the greatest pollution values were recorded during 1997 and 2002, and for sulphurs also in 1999 and 2003. The analyzed ion concentrations are still significantly higher than in other profiles, with the exception of lead and cadmium, where pollution is the greatest in the Oloví profile. However, in 2008 the measured values for all indicators did not exceed valid limits.
Our study concerns the effects of exposure to lead chloride on the morphology, K+ efflux, SO4 − influx and GSH levels of the human erythrocyte. Blood was collected in heparinized tubes and washed three times. The cells were suspended at 3% hematocrit and incubated for 1 h at 25°C in a medium containing increasing concentrations of lead chloride (0, 0.3, 0.5 and 1 μM). After incubation, the suspensions were centrifuged and the erythrocyte pellets were divided into three aliquots for testing. The results show: an increase in the permeability of erythrocytes treated with lead chloride with consequent damage and cellular death, especially in the presence of high concentrations; an increase in potassium ion efflux; alterations in the morphology and membrane structure of the red blood cells; and a decrease in sulphate uptake, due either to the oxidative effect of this compound on the band 3 protein, which loses its biological valence as a carrier of sulphate ions, or to a decrease in the ATP erythrocyte concentration. In conclusion, the exposure of erythrocytes to Pb2+ ions leads to a reduction in the average lifetime of the erythrocytes and the subsequent development of anemia. These data are discussed in terms of the possible effect of lead on the reduction-oxidation systems of the cell. Oxidant agents, such as lead, are known to cross-link integral membrane proteins, leading to K/Cl-cotransport. The increased K+ efflux affects the altered redox state.
The objective of the experiment was to determine the effect of nutrients (different doses of chlorine, sulphates and calcium as well as different forms of nitrogen fertilizers: Ca(NO3)2 + NH4NO3, NH4NO3, NH4NO3 + CaCl2, NaNO3) on yield and content of N-NO3, Nog., P, K, Ca, Mg and Na in butter lettuce (Lactuca sativa L.) cv. Vilmorin. A pot experiment with four replications was repeated three times in 2007 (from 30th January and from 30th March) and in 2008 (from 31st March). It was established in the ‘Plant House’ of the Chair of Agricultural Chemistry and Environmental Protection UWM in Olsztyn. Lettuce seedlings were planted into pots containing 2 dm3 substratum. Nitrogen was applied three times, every 10 days, each dose consisting of 100 mg N.dm-3 of substratum applied to soil; identical doses of phosphorus, potassium and magnesium were introduced to the substratum before planting lettuce. Irradiation period was 12 hours every day. Lettuce was harvested after 6 weeks. Determinations of Nog (Kjedahl’s method), P (vanadium- molybdenum method), K, Ca, Na (flame photometry – ESA), Mg (atomic absorption spectrophometry – ASA) were performed having wet mineralised plant samples in H2SO4. Concentration of nitrates (V) was determined in fresh matter (potentiometrically, using a ion-selective electrode) in a 0.03 mol.dm-3 CH3COOH according to NOWOSIELSKI (1988). The smallest number of lettuce heads (statistically significant) was obtained after NaNO3 fertilization. The concentration of N-NO3 declined advantageously following an NaNO3 treatment. In contrast, the highest accumulation of nitrates(V) occurred after application of lime saltpetre in conjunction with ammonium nitrate. The composition of minerals in butter lettuce cv. Vilmorin, such as phosphorus, potassium, magnesium and sodium, was more beneficially affected by fertilization with sulphate compounds (K2SO4 + MgSO4) rather than chlorine compounds (KCl + MgCl2). Soda nitre significantly depressed the content of magnesium and calcium in plants, had no effect on the concentration of phosphorus and increased accumulation of sodium and potassium.
This work was designed to find the cause of the delay in hydrogen sulfide dissimilation in Desulfotomaculum acetoxidans DSM 771, which is dependent on the sulfate uptake. This bacterium grown without addition of any aromatic compound was shown by spectrum analysis with the methylene method to contain hydroxy-benzoate derivatives. The presence of these compounds was confirmed by HPLC in fractions obtained from cell walls after 15 days of culture. The test with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt seemed to indicate the presence of peroxidase, which probably oxidized benzoate to its hydroxy derivatives. The test with 5-sulfo-salicylic acid proved the ability of the investigated strain to utilize arylsulfates and to reduce sulfate group to hydrogen sulfide. On the basis of the above data, we propose the following sequence of reactions: 1, benzoate secretion; 2, benzoate hydroxylation; 3, sulfonation of hydroxy-benzoate derivatives.
The effect of a concentration of heavy metal ions (Pb2+, Cd2+, Hg2 + and Zn2+) on the process of dissimilative reduction of sulfates in medium containing active Desulphotomaculum ruminis bacteria was studied. Both tolerable and toxic concentrations of the mentioned ions were determined. According to the degree of their toxicity the following ion sequence was established: Cd2 + > Zn2+ > Hg2+ > Pb2+, but only the presence of mercury ions caused death of the bacteria.
The capability of reduction of oxidized sulphur compounds (sulphates, sulphites and thiosulphates) by wild strains of sulphate reducing bacteria (SRB) Desulfovibrio desulfuricans DV-5/86 and Desulfotomaculum nigriflcans DT-5/86 was estimated basing on dynamics of hydrogen sulphide liberation. The effectiveness of these processes was correlated with the biocorrosion rate of metallic copper in artificial aqueous media containing above mentioned substrates. It was demonstrated that corrosive aggressiveness of used media with selected sulphur compounds and investigated bacteria strains were the highest in the presence of S2O3-2 ions and the lowest in the system containing SO4-2 ions.
This paper presents results of investigations on physicochemical treatment of vegetable oil refinery wastewater (VORW), namely acid and technological wastewater. The study has shown that VORW has a varying high pollution load (organic matter, sulfates, phosphates and chlorides) and the removal of these pollutants from acid wastewater was more effective than that from technological wastewater; the removal of suspended solids and solvent extractables was relatively higher than that of BOD5 and COD. The use of calcium chloride and alum as coagulants increases the concentration of chlorides in the final treated wastewater. The results also showed that physicochemical treatment processes significantly influence the relative biodegradability of the organic matter in the wastewater.
This paper presents studies on the effects of manganese, barium, zinc, aluminium and copper ions on the rate of biological sulfates reduction by Desulfotomaculum ruminis bacteria. We determinated the concentrations of these ions which totally inhibited the process. The anions we studied can be arranged according to increasing poisonous properties: Mn2+
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