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Number of results: 96
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Abstract

In this study, the spatial variation of daily and monthly concentration precipitation index and its aggressive-ness were used in 23 rainfall stations in the extreme north-east of Algeria over the period 1970–2010. The trend was analysed by the Mann–Kendall (MK) test. The results show that daily precipitation concentration index (CI) values are noticeably higher in places where the amount of total precipitation is low, the results of MK test show that areas of high precipitation concentration tend to increase. The seasonality and aggressiveness of precipita-tion are high in the eastern and western parts of the study region (eastern and central coastal of Constantine catchments), whereas a moderately seasonal distribution with low aggressiveness is found in the middle of the study area (plains and central Seybouse catchment). As a result, the modified Fournier index (MFI) has a signifi-cant correlation with annual precipitation, whereas the CI and monthly precipitation concentration index (PCI) show an opposite correlation in relation to annual precipitation.
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Authors and Affiliations

Hanane Bessaklia
Abderrahmane Nekkache Ghenim
Abdessalam Megnounif
Javier Martin-Vide
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Abstract

The aim of the research conducted in a 2-year pot experiment in an unheated plastic tunnel was to determine suitability of Miscanthus × giganteus for phytoextraction of nickel from soil as well as to assess tolerance of this species on increasing concentrations of this metal in soil. Pots were filled with mineral soil (sand) and a mixture of soil with high-moor peat and three levels of nickel were introduced, i.e. 75 mg dm-3, 150 mg dm-3 and 600 mg dm-3 and the control combinations used substrates without the addition of nickel. Nickel was introduced only in the first year of the experiment in the form of nickel sulfate (NiSO4 · 6H2O). Miscanthus × giganteus accumulated a considerable amount of nickel in biomass. Miscanthus × giganteus growing in contaminated mineral soil turned out to be a species tolerant to high nickel concentrations

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Authors and Affiliations

Maciej Bosiacki
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Abstract

One of the concepts of the ventilation rate control in buildings with dense and unpredictable occupancies is based on the CO2 measurements. There are many limitations regarding the validity of CO2 measurement inputs as suitable to the ventilation rate control. Verifying research has been conducted in an air-conditioned auditorium, in the real conditions at altered ventilation air thermal parameters and variable occupancy. The CO2 and the number concentrations of the fine and coarse aerosol particles(> 0.3 μm) and bioaerosol particles (bacteria and staphylococci) as well as the indoor air thermal parameters were measured in the individual sectors of the occupied area. The sensory assessments and instrumental determinations of the acceptability of indoor air quality (ACC) were also performed. The ventilation control strategy based, apart from the CO2 measurements, on the continuous monitoring of the perceived air quality (PAQ) in the auditorium sectors has been suggested. The PAQ monitoring could be accomplished by aerosol concentration measurements and the ACC instrumental determinations. This strategy should ensure a desired PAQ in sectors which benefit the occupants' comfort, health and productivity as well as energy savings not only in the case of its implementation in the considered auditorium.
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Authors and Affiliations

Bernard Połednik
Marzenna Dudzińska
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Abstract

The probability density functions were used to forecast the air quality in several monitoring sites located in Worek Żytawski region. Prediction of percentile 99.8 value (the maximum allowable 30-minute pollutant concentration) was made on the basis of the frequency function, which represented the annual distribution of SO2. Analysing the historical SO2 concentration data sets identified the form of distribution. The parameters of the distribution were estimated basing upon the annual average concentration prognosis. Then, the preliminary predicted distribution of S02 was verified every month by taking into account successively upcoming concentrations values recorded during the analysed period. The results proved that the air quality estimation obtained with the presented method of verification at the end of September and the ones typically calculated at the end of the year were similarly accurate.
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Authors and Affiliations

Jerzy Zwoździak
Wiwiana Szalińska
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Abstract

This study shows the results of flotation concentration of mica minerals from kaolinised granite taken from the “Bašića bare” deposit – Kobaš, Srbac, The Republic of Srpska (B&H). Mineralogical composition of kaolinised granite is as follows: kaolinite, feldspar, quartz, and mica. After separating >0.630 mm, and <0.043 mm size class where kaolinite is concentrated, the rest is –0.630+0.043 mm class containing quartz, feldspar and mica. The mica concentrate was obtained by the flotation concentration, while feldspar and quartz were in the flotation underflow. According to the mineralogical analysis, the most abundant minerals are mica and chlorite/clays, while quartz and feldspar occur much less, and accessory minerals are represented in trace. The semi-quantitative mineralogical analysis obtained by the X-ray powder diffraction (XRPD) method of the mica concentrate amount to: mica ≈55%, chlorite/clays ≈35%, quartz ≈5%, feldspars (plagioclase and K-feldspars combined) ≈5%.

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Authors and Affiliations

Živko T. Sekulić
Slavica R. Mihajlović
Jovica N. Stojanović
Branislav B. Ivošević
Vladan D. Kašić
Miroslav R. Ignjatović
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Abstract

The present study modelled the effects of operational parameters on the performance of the Falcon concentrator. For this purpose, the Falcon L40 concentrator was tested in narrow particle-size fractions (−600 + 425 μm, −425 + 300 μm, −300 + 212 μm, −212 + 150 μm, −150 + 106 μm, and −106 + 75 μm) at different washing water pressures and artificial gravity forces generated by a spinning bowl. The test samples were prepared artificially, comprising 2% magnetite (Fe3O4) and 98% calcite (CaCO3) by weight. The recovery and grade values of the 60 experimental conditions were investigated and compared for different operational parameters, including particle-size distributions, water pressures, and artificial gravity forces. Two empirical models were developed using non-linear regression analysis to indicate the effects of the operating parameter of the Falcon concentrator on its recovery and grade values. The operational parameters were found to impact the separation performance considerably. Therefore, the Falcon concentrator should operate under optimum conditions, which can be easily predicted using these models, to achieve improved recovery and grade values.
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Authors and Affiliations

Namik Atakan Aydogan
1
ORCID: ORCID
Murat Kademli
1
ORCID: ORCID

  1. Hacettepe University, Mining Engineering Department, Turkey
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Abstract

Whereas the use of biofuels has attracted increasing attention, the aim of this paper is to investigate the possibility of using sewage sludge as biofuel. Preparation of untreated and stabilised sludge with natural additives is described, as well as combusting method applied and experimental results of combusting are presented based on the assessment of composition of emitted pollutants and their concentrations in the exhaust gas. NOx formation in the exhaust gas has been analysed in depth. The results of investigations have shown that the use of dried sewage sludge possesses a positive energy balance. Therefore, the sludge may be used as fuel. The obtained experimental results demonstrate that during combustion, pollutant concentrations vary depending on oxygen content (O2), while formation of nitrogen oxides is strongly influenced by fuel-bound nitrogen. Also, a generalized equation of calculating fuel bound nitrogen conversion into NOx is presented.

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Authors and Affiliations

Nora Turkienė
Aušra Zigmontienė
Kęstutis Buinevičius
Raminta Plečkaitienė
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Abstract

The aim of the project was to collect experimental data regarding local distributions of fluid velocity and inert tracer concentration in a tank reactor with turbulent flow. The experiments were performed in a microscale in a region of tracer fluid injection. The results of experiments can be used for direct validation of currently developed CFD models, particularly for time-dependent mixing models used in LES.

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Authors and Affiliations

Łukasz Makowski
Wojciech Orciuch
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Abstract

It is meaningful to study the issues of CO migration and its concentration distribution in a blind gallery to provide a basis for CO monitoring and calculation of fume-drainage time, which is of a great significance to prevent fume-poisoning accidents and improve efficiency of an excavation cycle. Based on a theoretical analysis of a differential change of CO mass concentration and the CO dispersion model in a fixed site, this paper presents several blasting fume monitoring test experiments, carried out with the test location to the head LP in arrange of 40-140 m. Studies have been done by arranging multiple sensors in the arch cross-section of the blind gallery, located at the Guilaizhuang Gold Mine, Shandong Province, China. The findings indicate that CO concentrations in the axial directions are quadratic functions with the Y and Z coordinate values of the cross-section of the blind gallery in an ascending stage of CO time- -concentration curve, with the maximum CO concentrations in Y = 150 cm and Z = 150 cm. Also, the gradients of CO concentration in the gallery are symmetrical with the Y = 150 cm and Z = 150 cm. In the descending stage of CO time-concentration curve, gradients of CO concentration decrease in lateral sides and increase in the middle, then gradually decrease at last. The rules of CO concentration distribution in the cross-section are that airflow triggers the turbulent change of the CO distribution volume concentration and make the CO volume concentration even gradually in the fixed position of the gallery. Moreover, the CO volume concentrations decrease gradually, as well as volume concentration gradients in the cross-section. The uniformity coefficients of CO concentration with duct airflow velocities of 12.5 m/s, 17.7 m/s and 23.2 m/s reach near 0.9 at 100-140 m from the heading to the monitoring spot. The theoretical model of a one-dimensional migration law of CO basically coincides with the negative exponential decay, which is verified via fitting. The average effective turbulent diffusion coefficient of CO in the blind gallery is approximate to 0.108 m2/s. There are strong linear relationships between CO initial concentration, CO peak concentrations and mass of explosive agent, which indicates that the CO initial concentration and the CO peak concentration can be predicted, based on the given range of the charging mass. The above findings can provide reliable references to the selection, installation of CO sensors and prediction of the fume-drainage time after blasting.
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Authors and Affiliations

Yang Cao
Hongguang Ji
Yuezheng Zhang
Song Li
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Abstract

Simultaneous measurements of the indoor and outdoor particle mass (PM) and particle number (PN) concentrations as well as the air temperature, relative humidity (RH), and CO2 concentrations have been conducted in 6 occupied (L) and unoccupied (V) classrooms in 3 secondary schools in Lublin, Poland, in the heating (H) and summer (S) seasons. The schools were located in residential areas where the majority of private houses are heated by means of coal-burning stoves. The ratios of the average particle concentrations in occupied and unoccupied classrooms (L/V) were higher during the heating season measurements. The ratios of the average particle concentrations during the measurements in the heating and summer seasons (H/S) were higher in occupied classrooms. In both seasons the average PM and PN concentrations amounted to 239 μg/m3 and 7.4×103/cm3 in the occupied classrooms, and to 76 μg/m3 and 5.4×103/cm3 in the unoccupied classrooms, respectively. The particle exposures experienced by students were higher in the monitored classrooms than outdoors and were on average about 50% higher in the heating than in the summer season. A positive correlation between mass concentrations of coarse particles and indoor air temperature, RH and CO2 concentrations in both seasons was observed. The concentrations of fine particles were negatively correlated with the indoor air parameters in the heating season, and positively correlated in the summer season.

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Authors and Affiliations

Bernard Połednik
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Abstract

The region’s development potential is a set of endogenous features that determine the growth of the local economy. It supports the development of knowledge, innovation and eff ective competition on global markets. The publication argues that saturation with potential may not be enough to cause economic growth. The distribution of potential is also important: concentration is its catalyst. The study proposes a method for measuring the concentration of potential. It has also been shown that the size of the regional economy depends on the distribution of potential in the region.

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Authors and Affiliations

Michał Nadolny
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Abstract

Research concerning temporal variations of suspended sediment concentration during period of high water stages was done in the lower course of the Obra River near Międzyrzecz (Western Poland). The analysis regarding dependence of mean suspended sediment concentration and discharge allowed to determine the way of suspended sediment supply to the river bed during high water stages. It was supposed that exposures of glacial and fluvioglacial sediments in high concave banks could be an important factor influencing the amount of delivery of suspended material. Besides, normal hysteretic loops (oriented clockwise) were observed in cross-sections 4 and 5. That fact would suggest that transported material originates form the Obra River bed or its vicinity. The process of sediment accretion was observed on a fragment of drowned floodplain during high water stages. Collection of samples of freshly deposited sediment and grain size analysis allowed to illustrate the mechanism of forming floodplain sediments. It also was possible to draw near conditions of forming such sediments in the past.
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Authors and Affiliations

Zygmunt Młynarczyk
Marcin Słowik
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Abstract

Serum concentration of thyroid hormones in healthy dogs varies according to age, sex, breed or professional activity. The aim of this study was to determine the influence of both age and dogs’ work involvement on TSH and thyroid hormones values. Thyroid-stimulating hormone (TSH), total thyroxine (tT4) and free thyroxine (fT4) were tested in the serum of 57 healthy, German Shepherd dogs. The dogs were divided into study groups according to age: dogs aged 3 to 6 years (A), dogs over the age of 6 years (B) and involvement: police-working dogs (C) and accompanying animals (D). Mean values of TSH, tT4 and fT4 ranged from 0.19 to 0.31 ng/ml, 15.58 to 17.25 nmol/L and 11.83 to 17.89 pmol/L, respectively. The highest values of TSH were in group B and the lowest were in group A, while there was an inverse dependence in case of fT4 concentration. The highest mean values of tT4 were in dogs in group C and the lowest in group B. There were statistically significant differences in TSH (p=0.007) and fT4 (p=0.003) concentrations between the age groups. The results indicate that a dog’s age is an important factor in the case of thyroid profile results interpretation.
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Authors and Affiliations

I. Taszkun
1
A. Milczak
2
G. Kalisz
3
P. Wilkołek
1
J. Zwolska
4
M. Szczepanik
1

  1. Subdepartment of Clinical Diagnostics and Veterinary Dermatology, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Głeboka 30, 20-612 Lublin, Poland
  2. Department and Clinic of Animal Internal Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Głeboka 30, 20-612 Lublin, Poland
  3. Department of Biopharmacy, Faculty of Pharmacy, Medical University of Lublin, ul. W. Chodzki 4a, 20-093 Lublin, Poland
  4. Department and Clinic of Animal Surgery, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Głeboka 30, 20-612 Lublin, Poland
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Abstract

Nontuberculous mycobacteria (NTM) have recently emerged as important bacterial pathogens of animals and humans. Of particular concern is the high level of antimicrobial resistance displayed by these organisms, which complicates treatment and potential successful outcomes. Here, we evaluated the potential of Carlina acaulis L. as a source of novel anti-mycobacterial agents. Our goal was to measure the activity of aqueous, ethanol, and chloroform C. acaulis root extracts against 99 NTM strains. GC-MS spectroscopy analyses were performed to deliver qualitative and quantitative data on the composition of C. acaulis extract. In our study, we have shown for the first time the activity of C. acaulis extracts against NTM. The highest activity was exhibited by the chloroform extract, which inhibited the growth of more than 90% of the strains at the dose of 100 μg/mL (MIC90 = 100 μg/mL). The results of the GC-MS analysis of the C. acaulis chloroform extract contributed to the identification of 37 compounds, with carlina oxide as the most representative compound (69.52%) followed by 3,4-dihydro-2H-phenanthren- -1-one (6.54%) and stigmast-5-en-3-ol (4.14%). Our results indicate that C. acaulis chloroform and ethanol extracts have potential for treatment of NTM infections and that this plant contains anti-mycobacterial compounds.
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Authors and Affiliations

K. Puk
1
J. Wawrzykowski
2
L. Guz
1

  1. Department of Biology and Fish Diseases, Faculty of Veterinary Medicine, University of Life Sciences, Akademicka 12, 20-033 Lublin, Poland
  2. Department of Biochemistry, Faculty of Veterinary Medicine, University of Life Science in Lublin, Akademicka 12, 20-033 Lublin, Poland
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Abstract

Nontuberculous mycobacteria (NTM) have recently emerged as important bacterial pathogens of both animals and humans. In this study, we aimed to evaluate the effect of a combination of ten antibiotics with an inhibitor of efflux pumps (EPI), i.e. berberine (BER), against 6 strains of NTM. Our results showed that the BER potentiated the anti-mycobacterial activities of the antibiotics. Overall, our findings show the importance of BER in increasing the efficacy of antibiotics in NTM.
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Bibliography


Gaba S, Saini A, Singh G, Monga V (2021) An insight into the medicinal attributes of berberine derivatives: a review. Bioorg Med Chem 38: 116143.
Gentry EJ, Jampani HB, Keshavarz-Shokri A, Morton MD, Velde DV, Telikepalli H, Mitscher LA, Shawar R, Humble D, Baker W (1998) Antitubercular natural products: berberine from the roots of commercial hydrastis canadensis powder. Isolation of inactive 8-oxotetrahydrothalifendine, canadine, beta-hydrastine, and two new quinic acid esters, hycandinic acid esters-1 and -2. J Nat Prod 61: 1187-1193.
Guz L, Puk K (2022) Antibiotic susceptibility of mycobacteria isolated from ornamental fish. J Vet Res 66: 69-76.
Menichini M, Lari N, Rindi L (2020) Effect of efflux pump inhibitors on the susceptibility of Mycobacterium avium complex to clarithromycin. J Antibiot 73: 128-132.
Puk K, Guz L (2020) Occurrence of Mycobacterium spp. in ornamental fish. Ann Agric Environ Med 27: 535-539.
Song L, Wu X (2016) Development of efflux pump inhibitors in antituberculosis therapy. Int J Antimicrob Agents 47: 421-429.
Van Ingen J, Boeree MJ, Van Soolingen D, Mouton JW (2012) Resistance mechanisms and drug susceptibility testing of nontuberculous mycobacteria. Drug Resist Updat 15: 149-161.
Wang Y, Fu H, Li Y, Jiang J, Song D (2012) Synthesis and biological evaluation of 8-substituted berberine derivatives as novel an-ti-mycobacterial agents. Acta Pharm Sin B 2: 581-587.
Zhou XY, Ye XG, He LT, Zhang SR, Wang RL, Zhou J, He ZS (2016) In vitro characterization and inhibition of the interaction between ciprofloxacin and berberine against multidrug-resistant Klebsiella pneumoniae. J Antibiot 69: 741-746.
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Authors and Affiliations

K. Puk
1
L. Guz
1

  1. Department of Biology and Fish Diseases, Faculty of Veterinary Medicine, University of Life Sciences, Akademicka 12, 20-033 Lublin, Poland
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Abstract

During the cruise of the research ship r/v Oceania owned by the Institute of Oceanology of the Polish Academy of Sciences in Sopot a research on mineral suspension concentration and dispersion distributions was conducted. The research area included the western part of the Baltic Sea, the Danish Straits, the Norwegian Sea, the waters around Spitsbergen and the North Atlantic Ocean. Samples of water were collected from the surface layer. They were subjected to microscopic analysis. Measurements were done with a projection microscope (magnification lOOOx) and using the Burker's table. After counting the particles dispersion distribution was determined. The largest concentration of mineral suspension was noted offshore in the Norwegian Sea and around Spitsbergen and the smallest in the central Atlantic Ocean.

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Authors and Affiliations

Henryk Gurgul
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Abstract

Data sets gathered continuously in air monitoring systems are never entirely complete. The problem of missing data in monitoring measure series often has to be solved by modeling. A new method of air monitoring data modelling was tested in the paper. Regional diurnal concentration courses (RDCCs) were used as the main source of knowledge of predicted time series during specified days. The paper presents a comparison of predicted and measured diurnal concentration patterns of two frequently used parameters in air monitoring (PM10 and NO2). The analysis was based on hourly time series of these air pollutants collected in a 3-year period at nine monitoring stations in the Lodz Region. It was shown that well determined regional diurnal concentration patterns could be useful to missing data modelling at the specified monitoring site. Improvement of modelling accuracy is possible after modification of modelling results by adding local difference vectors (LDVs), describing the specificity of the monitoring station.
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Authors and Affiliations

Szymon Hoffman
Rafał Jasiński
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Abstract

The intensive agricultural use of the land affects both quantity and quality of river water in the catchment area. Such impact is visible also in the Szreniawa River catchment in the Małopolskie Voivodeship. The combination of intensive plowing and soil susceptibility to water erosion are the main causes of soil and nutrients depletion during the heavy rainfall. The aim of the study is to determine changes in the water quality in the Szreniawa River catchment compared to the agri-culture use and precipitation level.

The quality of surface water has been analysed in the river catchment area in three sampling points. The concentration of the total suspended soils in the samples collected after heavy rainfall in August 2017 reached a value of 837 mg·dm–3. The average concentrations of N-NO3 in the years of 2016–2019 ranged from 0.16 to 13.46 mg·dm–3, with the highest val-ues in the summer (up to 13.46 mg·dm–3). The concentration of N-NH4 and P-PO4 in the Szreniawa water was affected by precipitation. The highest value of average concentration of N-NH4 3.00 mg·dm–3 was recorded in the autumn of 2019 in the middle section of the river. The highest value of P-PO4 0.90 mg·dm–3 was recorded in the autumn of 2019 mostly due to water erosion of the loess areas. Erosion has been caused by the short-term heavy rainfall. As a result, suspended solids, soluble and insoluble phosphorus compounds leaked to the river.

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Authors and Affiliations

Agnieszka W. Kowalczyk
ORCID: ORCID
Marek Kopacz
ORCID: ORCID
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Abstract

Koumiss has beneficial therapeutic effects on bacterial diseases. Four antibacterial com- pounds from yeasts ( Kluyveromyces marxianus and Saccharomyces cerevisiae) in koumiss were evaluated for their antibacterial effects against three Gram-negative bacteria, three Gram-positive bacteria and five pathogenic Escherichia coli strains. The antibacterial compounds from yeasts in koumiss were extracted, and their main components were determined. The inhibition zones were analyzed, and their minimum inhibition concentrations (MICs) and minimum bactericidal concentrations (MBCs) were determined. Aqueous phases of Kluyveromyces marxianus and Saccharomyces cerevisiae at pH 2.0 and 8.0 produced larger inhibition zones than those in other phases, and then antibacterial compounds from K. marxianus (K2, pH=2.0; K8, pH=8.0) and S. cerevisiae (S2, pH=2.0; S8, pH=8.0) were obtained. Their main components were organic acids and killer toxins. K2 had more propanoic acid and S2 had more oxalic acid than others. The inhibition zones of K2, K8, S2 and S8 against three Gram-negative bacteria and three Gram-positive bacteria were 12.03-23.30 mm, their MICs were 0.01-0.13 g/mL, and MBCs were 0.03-0.50 g/mL. Meantime, the inhibition zones of K2, K8, S2 and S8 against five pathogenic E. coli were 16.10-25.26 mm, their MICs were 0.03-0.13 g/mL, and MBCs were 0.13-1.00 g/mL. These four antibacterial compounds from yeasts in koumiss had broad antibacterial spectrum. In addition, K2 and S2 were better than K8 and S8.
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Authors and Affiliations

Y.J. Chen
1 2
C.G. Du
1 3
Y.Q. Guo
1
Y.F. Zhao
1
C. Aorigele
2
C.J. Wang
3
H. Simujide
2
W. Aqima
2
X.Y. Zhang
1

  1. Vocational and Technical College, Inner Mongolia Agricultural University, Baotou 014109, P.R. China
  2. College of Animal Science, Inner Mongolia Agricultural University, Hohhot 010018, P.R. China
  3. College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, P.R. China
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Abstract

Two phase flow experiments with different superficial velocities of gas and water were performed in a vertical upward isothermal cocurrent air-water flow column with conditions ranging from bubbly flow, with very low void fraction, to transition flow with some cap and slug bubbles and void fractions around 25%. The superficial velocities of the liquid and the gas phases were varied from 0.5 to 3 m/s and from 0 to 0.6 m/s, respectively. Also to check the effect of changing the surface tension on the previous experiments small amounts of 1-butanol were added to the water. These amounts range from 9 to 75 ppm and change the surface tension. This study is interesting because in real cases the surface tension of the water diminishes with temperature, and with this kind of experiments we can study indirectly the effect of changing the temperature on the void fraction distribution. The following axial and radial distributions were measured in all these experiments: void fraction, interfacial area concentration, interfacial velocity, Sauter mean diameter and turbulence intensity. The range of values of the gas superficial velocities in these experiments covered the range from bubbly flow to the transition to cap/slug flow. Also with transition flow conditions we distinguish two groups of bubbles in the experiments, the small spherical bubbles and the cap/slug bubbles. Special interest was devoted to the transition region from bubbly to cap/slug flow; the goal was to understand the physical phenomena that take place during this transition A set of numerical simulations of some of these experiments for bubbly flow conditions has been performed by coupling a Lagrangian code, that tracks the three dimensional motion of the individual bubbles in cylindrical coordinates inside the field of the carrier liquid, to an Eulerian model that computes the magnitudes of continuous phase and to a 3D random walk model that takes on account the fluctuation in the velocity field of the carrier fluid that are seen by the bubbles due to turbulence fluctuations. Also we have included in the model the deformation that suffers the bubble when it touches the wall and it is compressed by the forces that pushes it toward the wall, provoking that the bubble rebound like a ball.
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Authors and Affiliations

José Muñoz-Cobo
Sergio Chiva
Mohamed El Aziz Essa
Santos Mendes
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Abstract


Analysis of lead and cadmium concentrations in the air comparing concentration values difference between heating and summer seasons was carried out in the paper. Relevant procedure was adopted to find out if the concentration values in these two seasons differed in kind. The concentration seasonal difference was not found in case of cadmium but it was found for lead. It was proved in further part of the paper that the analysed mean 24-hour Pb concentrations for heating season could be presented as a sum of the mean annual background concentration and the concentration values resulted from Pb emission from sources active only in the heating season. In the area where the measurements were carried out residential furnaces were this kind of sources. The cumulative distribution function of the mean 24-hour lead concentration resulted from Pb emissions in the heating season was determined using two-layer neural network. It was found according to this approach that Pb concentration as the result of Pb emissions from residential furnaces, for 145 days, i.e. 80% of the heating season period, were at least two-fold lower than the lead concentration values as the result of Pb emission from the all year active sources. Only for 14 days emission sources active in the heating season produced Pb concentrations higher than Pb mean annual background concentration.
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Authors and Affiliations

Czesław Kliś
Stanisław Hławiczka
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Abstract

The paper characterizes the state of air pollution on the ground of Wroclaw in the period of 1990 to 1999. The base air contamination for Wroclaw: dust, SO2, NO,, F, Pb. Cd, B(a)P were analyzed, also the source of emission, monitoring and method of indicates were discussed. The investigations show significant decrease of the concentration: dust, SO,, the high level of the concentration of NO, and F with the increasing tendency at the end of the observation period and the insufficient monitoring of the particularly dangerous contamination for the health: Pb, Cd, B(a)P. The received results indicate the necessity of the reorganization of the existing air monitoring system with particular regard to communication contamination. In this work the new principle for the air quality control in Wroclaw has been proposed.
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Authors and Affiliations

Jolanta Tracz
Jolanta Prawdzik

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