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Abstract

Due to more and more increasing role of pollution surface waters in environment - particularly in populous regions - in this paper the problem of the influence of the town of Nakło city on purity of the Noteć river has been presented. Hydrochemical investigation of the Noteć river in the region of the community Nakło indicated II and III water quality classification. The town of Nakło discharges very much pollution into this river. In spite of recent certain improvement in comparison to 1993-1995 years the annual amount of pollution flowing from the town into the river is still too large and it is 3149 Mg of suspended matter, 266 Mg of nitrogen and 69 Mg of phosphorus.
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Authors and Affiliations

Czesława Trojanowska
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Abstract

The laminar flow around two side-by-side circular cylinders was numerically investigated using a vortex-in-cell method combined with a continuous-forcing immersed boundary method. The Reynolds number (Re) of the flow was examined in the range from 40 to 200, and the distance between the cylinders varies from 1.2 D to 6 D, where D is the cylinder diameter. Simulation results show that the vortex wake is classified into eight patterns, such as single-bluff-body, meandering-motion, steady, deflected-in-one-direction, flip-flopping, anti-phase-synchronization, in-phase-synchronization, and phase-difference-synchronization, significantly depending on the Re, the cylinder distance, and the initial external disturbance effects. The anti-phase-synchronization, in-phase-synchronization, and phase-difference-synchronization vortex patterns can be switched at a low Re after a long time evolution of the flow. In particular, the single-bluff-body and flip-flopping vortex patterns excite the oscillation amplitude of the drag and lift coefficients exerted on the cylinders.
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Bibliography

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Authors and Affiliations

Van Luc Nguyen
1
ORCID: ORCID
Duy Knanh Ho
1

  1. Institute of Engineering and Technology, Thu Dau Mot University, Binh Duong Province, Vietnam
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Abstract

Time series analysis ofmonthly and daily SO2 data were considered for the detection of trends in SO2 due to possible effect of the emission abatement strategy in the Black Triangle region. Using a time series model, the main components were extracted from the original SO2 time series. Based on SO2 monitoring data from Czerniawa in Izery Mountains in Poland over the period 1993 -1998, our findings showed evidence of declining trends in SO2• A mean annual change of 14.1% was recorded in a 6-year record. It has also appeared that the exponential smoothing which considers a seasonal component and trends provided a reasonable fit to monthly mean SO2 values.
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Authors and Affiliations

Jerzy Zwoździak
Artur Gzella
Anna Zwoździak
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Abstract

Investigations were carried out in order to evaluate biodegradability of two pesticides - pure active substance 2,4-dichlorophenoxyacetic acid (2,4 D) and specific preparation created at the base of 2,4-D - Aminopielik 720. Biodegradation was carried out according to OECD standards - Method 301E and 303A. After biodegradation toxicity of intermediates was also determined. Investigated preparations were biodegradable in coupled units test Biodegradation rate, observed at the base of COD standard analysis, was over 90%. Intermediates didn't show significant toxicity with reference to fish, algae and daphnia.
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Authors and Affiliations

Elżbieta Grabińska-Sota
Dorota Kalka
Barbara Wiśniowska
Beata Ścieranka
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Abstract

Study on water and bottom sediment quality of the Kozłowa Góra drinking water reservoir in Silesian province was carried out. Heavy metal concentrations in water body and bottom sediment of the reservoir were determined. Water quality assessment was perform by comparing concentration of heavy metals to standards for I class water quality. The degree of sediment contamination was carried out by calculating cumulation coefficient: sediment/water and sediment/ geochemical background. Present water and sediment contamination in the reservoir was compared with the state 20 years ago, which was a period of intensive metallurgical industry development in this region. At the same time, heavy metals speciation in sediment for those of high rate accumulation: Zn, Pb and Cd was determined. The results of heavy metal speciation in sediment provided a basis to secondary water pollution assessment, due to migration of these metals to water body.
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Authors and Affiliations

Stefania Ryborz-Masłowska
Katarzyna Moraczewska-Majkut
Józefa Krajewska
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Abstract

In 1999 research on the range of pollution of fishes in antropogenie water ecosystem was carried out. These are the first results of investigation on heavy metals in fishes of this part of Upper Silesia region, especially in the dam-reservoir of the Kłodnica river. Concentration of Pb, Cd, Cu, Ni, Zn, Cr, Mn, in flesh and liver of some species of fish (Rutilus rutilus, Tinca tinca, Cyprinus carpio, Esox Lucius, Perea fluviatilis) in antropogenie ecosystem of water is given. The Dzierżno Duże dam-reservoir is artificial reservoir on the Kłodnica river, which flows through the Silesia region, the most industrialized region in Poland. The Coal-mine waters and other industrial pollution were collected in the sediments in this lake for years. The range of heavy metals concentration is higher than established standards for fish-food. The investigations will be continued.
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Authors and Affiliations

Maciej Kostecki
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Abstract

The wearing courses (top layers) of the streets in towns are usually of asphalt concrete, paving stones or cement concrete blocks type. They must provide good load capacity, high friction, comfortable and quiet ride. The problem of traffic noise reduction by use of proper road surfaces is not very often addressed in Poland. Due to legislation and technical progress during the last decades, a substantial reduction of the power unit noise emitted by cars and trucks has been achieved. It is observed that nowadays even at low speeds typical for urban driving the dominating noise comes from the tyres. The paper compares typical road surfaces that are used in towns from the point of view of their influence on the traffic noise.
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Authors and Affiliations

Władysław Gardziejczyk
Jerzy A. Ejsmont
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Abstract

In 1998 microbiological investigation of water on eleven sample points, of the greatest antropogenie reservoir in the West-part of Upper Silesian Region was carried out. Total numbers of psychrophiles, mesophiles, Coliform bacteria was determined. In the estuary of Kłodnica river Coli-coefficient was 0.00004, coefficient of Coli-faecal type was 0.0009. These values indicate severe water pollution with faecal matter over the standards for waters and sewage waters. With the distance from estuary of Kłodnica river microbiological pollution factors decrease was observed. After 1 km Coli-coefficient was 100-product decrease. In the sample point at the end of longitude profile, near the dam vicinity, values of those indicators successfully decreased to 0.1 of the Coli-form and 1 for Coli-faecal type. In the 4 sample points along the length of left bank of second part of reservoir (West-part) the differentiation of water quality was observed between I and III quality classes. Decrease of numbers of faecal streptococci by flow-line from 6000 in the estuary of the Kłodnica river to 15 in the pelagic point and 4 in the end of reservoir was determined. Decrease in microbiological factor is the greatest on the first 1000 meters of longitude profile of the reservoir. Very important in decrease of bacteria numbers is sedimentation process of alochtonie suspended solids.
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Authors and Affiliations

Maciej Kostecki
Aleksandra Smyłła
Aleksandra Starczyńska

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