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Prediction of the Seasonal Changes of the Chloride Concentrations in Urban Water Reservoir

Abstract

This study investigated the possibility of using artificial neural networks to predict changes in the concentration of chloride ions in the urban ponds on the example of the inflow and outflow zones of water to and from the ponds Syrenie Stawy in Szczecin (NW-Poland). The possibility of using selected water quality indices (selected based on correlation matrix of water quality indices with Cl), in particular: COD-Cr, BOD5, DO, water saturation by O2 and NO2 and their influence on the chloride concentration forecast was tested.

Open access
Spatial Distribution of BTEX and Inorganic Pollutants During Summer Season in Yalova, Turkey

Abstract

The objective of this research is to determine the atmospheric concentrations and spatial distribution of benzene (B), toluene (T), ethylbenzene (E) and xylenes (X) (BTEX) and inorganic air pollutants (O3, NO2 and SO2) in the Yalova atmosphere during summer 2015. In this study, a combination of passive sampling and Geographical Information System-based geo-statistics are used with spatial statistics of autocorrelation to characterise the spatial pattern of the quality of air based on concentrations of these pollutants in Yalova. The spatial temporal variations of pollutants in the air with five types of land-use, residence, rural, highway, side road and industrial areas were investigated at 40 stations in Yalova between 7th August 2015 and 26th August 2015 using passive sampling. An inverse distance weighting interpolation technique was used to estimate variables at an unmeasured location from observed values at nearby locations. The spatial autocorrelation of air pollutants in the city was investigated using the statistical methods of Moran’s I in addition to the Getis Ord Gi. During the summer, highway and industrial sites had higher levels of BTEX then rural areas. The average concentration of toluene was measured to be 5.83 μg/m3 and this is the highest pollutant concentration. Average concentrations of NO2, O3 and SO2 are 35.64, 84.23 and 3.95 μg/m3, respectively. According to the global results of Moran’s I; NO2 and BTEX had positive correlations on a global space at a significant rate. Moreover, the autocorrelation analysis on the local space demonstrated significant hot spots on industrial sites and along the main roads.

Open access
Application of the reduced I-V Blaesser’s characteristics in predicting PV modules and cells conversion efficiency in medium and high insolation conditions

Abstract

The article presents theoretical foundations of application of the reduced I-V Blaesser’s characteristics in predicting a photovoltaic cell/module (PV) efficiency, together with calculation procedures. A detailed analysis of the error of this transformation method of characteristics was carried out. Its practical application in predicting efficiency of operation of various PV cells and modules in medium and high insulation conditions was demonstrated. The practical suitability of the presented method in early detection of ageing phenomena, such as, for example, absorber degradation taking place in PV modules, was demonstrated. The article was prepared on the basis of the results of testing five different PV modules with various constructions, made of different materials and absorbers, such as: c-Si, mc-Si, CIS, a-Si_SJ, a-Si_TJ. The used measurement data were collected during the 16-year period of the experimental PV modules testing system operation in Opole University, equipped with a data acquisition system.

Open access
Biodesulphurization of thiophene as a sulphur model compound in crude oils by Pseudomonas aeruginosa supported on polyethylene

Abstract

A new biodesulphurization method has been considered using Pseudomonas aeruginosa supported on polyethylene (PE) for biodesulphurization (BDS) of thiophene as an aromatic sulphur model compound of crude oils. Also the biodegradation of thiophene has been modified in the presence of potassium hexacyanoferrate(III) as a terminal electron acceptor to approach the maximum biodesulphurization efficiency. The obtaining results according to UV-Spectrophotometry at 240 nm, 83.3% of thiophene at the primary concentration of 50 mg/dm3, pH = 7, by 0.5 g of biocatalyst in 37°C after 4 h of contact time has been removed. The bacterial cells exhibited a greater and faster biodegradation in the presence of potassium hexacyanoferrate(III) and 94.8% of thiophene has been removed after 3 h of contact time. Kinetic study predicted chemisorption of thiophene on the surface of the biocatalyst, as it followed the pseudo-second-order rate equation. Morphology and surface functional groups of the biocatalyst have been investigated by SEM and FT-IR, respectively.

Open access
Comparison of PM10 washout on urban and rural areas

Abstract

This paper reports the results of research into the effectiveness of scavenging of PM10, resulting from the occurrence of solid and liquid hydrometeors. The measurement campaign was undertaken over 7 years and involved the registration of PM10 in areas which have different aerosanitary conditions (i.e. urban and undeveloped rural area). The analysis involved 426 observations taken at constant time intervals of 0.5 hour. The measurements of the concentration of PM10 were performed by means of a reference method accompanied by concurrent registration of basic meteorological parameters. It was indicated that in a urban location, the intensity of the local emission sources is a principal factor influencing the value of mass concentration changes and the effectiveness of the dust scavenging that accompanies a given type of precipitation. It was also noted that for the same intensity of precipitation, only the deposition of convective rainfall and long-term large-scale precipitation do not lead to statistically relevant differences in the value of mass concentrations of dust for both areas. It was indicated that during solid and liquid frontal precipitation of light intensity (< 0.5 mm·h−1), the effectiveness of PM10 removing is less in rural area. It was statistically proven that continuous precipitation of constant intensity and duration exceeding 2 hours has a similar effect of purifying the ambient air in both locations. The study revealed that short-term solid precipitation provides better characteristics of scavenging of PM10 compared with classic rainfall

Open access
The effect of tropospheric ozone on flavonoids and pigments content in common buckwheat cotyledons

Abstract

Tropospheric ozone forms in photochemical reactions or by refuse burning and combustion of exhaust gases from engines, and during some industrial processes. The mean ambient ozone concentration doubled during the last century, and in many urban areas has reached the phytotoxic level. In the present study, there was determined the effect of ozone fumigation on levels of individual flavonoids, chlorophylls, carotenoids and total phenols in the cotyledons of four common buckwheat cultivars (Hruszowska, Panda, Kora and Red Corolla). Six-day-old buckwheat seedlings were grown in controlled conditions and treated with an elevated dose of ozone (391 μg · m−3) during 5 days for 1 h each day. After the experiment, the cotyledons of the seedlings were analysed for individual flavonoids, chlorophylls, carotenoids and total phenols. Shoot elongation was also measured. Individual types of flavonoids in buckwheat cotyledons were found to respond to an elevated ozone dose in various ways. The response was also dependent on the cultivar evaluated. In the cotyledons of ozonized buckwheat seedlings, contents of C-glucosides of luteolin and apigenin decreased or did not change depending on the cultivar examined. In the case of flavonols, the contents of quercetin-3-O-rhamnosyl-galactoside and rutin (quercetin-3-O-rhamnosyl-glucoside) were markedly reduced in most cultivars. O3 had no effect on the level of anthocyanins and chlorophylls but it decreased carotenoids, and tended to inhibit buckwheat growth. In conclusion, a thesis can be formulated that, due to high reduction in important flavonoids, an elevated level of ambient ozone decreases the nutritional value of common buckwheat seedlings.

Open access
Example of sewerage system rehabilitation using trenchless technology

Abstract

The sewerage network in Poland, built in the early 20th century, has been losing its original water-tightness and flow capacity. To bring these characteristics back, rehabilitation works are performed. The initial capacity of sewers can be restored without affecting the urban environment thanks to the trenchless technology. The sewer subjected to rehabilitation receives a new internal leakproof layer capable of preventing groundwater infiltration as well as sewage leaks, which can contaminate the environment. This paper intends to compare the trenchless technology with traditional open cut trench excavation. In the study, two variants of trenchless rehabilitation were considered: one performed with the help of GRP panels and the other using cured-in-place pipe (CIPP) lining. Flow velocities and flow rates in the sewers before and after rehabilitation were compared. Also, selected economic and environmental aspects of sewer rehabilitation methods were examined.

Open access
Health and environmental applications of gut microbiome: a review

Abstract

Life on Earth harbours an unimaginable diversity of microbial communities. Among these, gut microbiome, the ecological communities of commensal, symbionts (bacteria and bacteriophages) are a unique assemblage of microbes. This microbial population of animal gut helps in performing organism’s physiological processes to stay healthy and fit. The role of these microbial communities is immense. They continually maintain interrelation with the intestinal mucosa in a subtle equilibrium and help the gut for different functions ranging from metabolism to immunologic functions like upgradation of nutrient-poor diets, aid in digestion of recalcitrant food components, protection from pathogens, contribute to inter- and intra-specific communication, affecting the efficiency as disease vectors etc. The microbial diversity in the gut depends upon environmental competition between microbes, their sieving effects and subsequent elimination. Due to wide diversity of anatomy and physiology of the digestive tracts and food habits, the gut microbiome also differs broadly among animals. Stochastic factors through the history of colonization of the microbiome in a species and in situ evolution are likely to establish interspecies diversity. Moreover, the microbes offer enormous opportunity to discover novel species for therapeutic and/or biotechnological applications. In this manuscript, we review the available knowledge on gut microbiome, emphasising their role in health and health related applications in human.

Open access
Impact of thermal treatment of mixtures of sewage sludge and plant material on selected chemical properties and Vibrio fischeri response

Abstract

The aim of the research was to evaluate the effect of temperature during the treatment process as well as the effect of adding plant materials to sewage sludge on selected chemical properties and Vibrio fischeri response. The mixtures were placed in a chamber furnace, under airless conditions. Two temperature procedures were applied: 300 and 600ºC; the exposure time in both cases was 15 minutes. Thermal treatment of sewage sludge without a plant component is not well-founded and may cause an increase in concentration of trace elements. Using the temperature of 300ºC caused significantly lower changes in the contents of total forms of trace elements than using the temperature of 600ºC. The metals extracted from the studied mixtures were not toxic for the Vibrio fischeri. In the case of the fractional composition of humic compounds, thermal treatment of mixtures of sewage sludge and plant materials is not beneficial in terms of labile fractions, but it had a beneficial effect on stabilizing the durable bonds between C compounds in those mixtures.

Open access
Polycyclic aromatic hydrocarbons removal from produced water by electrochemical process optimization

Abstract

Produced water is actually the wastewater separated from petroleum crude oil. Electrochemical-oxidation experiments was conducted for degradation of 16 priority polycyclic aromatic hydrocarbons (PAHs) using DSA type Ti/IrO2 anode. Laboratory scale batch reactor was used for degradation studies. To get the maximum PAHs removal electrochemical process optimized on three independent variable current density, pH and electrolysis time. The response surface modelling (RSM) based on a Box-Behnken design was applied to get appropriate experimental design. X 1, X 2 and X 3 are the coded factors of independent variables such as the current density, pH and electrolysis time, respectively. Maximum removal was 95.29% at optimized conditions such as current density of 9 mA/cm2, pH 3 and electrolysis time 3.7 h. Quadratic model was suggested best fit model. The results of the Analysis of Variances (ANOVA) for PAHs demonstrated that the model was highly significant.

Open access