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1
Content available Preliminary study on the influence of UV-C irradiation on microorganism viability and polyphenol compounds content during winemaking of ‘Regent’ red grape cultivar
Mijowska K., Cendrowski K., Grygorcewicz B., Oszmiański J., Nawrotek P., Ochmian I., Zielińska B.
Polish Journal of Chemical Technology
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2017
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Vol. 19, nr 2
130--137
EN
In this study, UV-C light was tested as an alternative method to inactivate microorganisms in the must of ‘Regent’ red grape cultivar. The control sample containing the microorganism diluted in a physiological NaCl solution was prepared to take into consideration different conditions of liquids, such as turbidity and colour. Additionally, the changes in the composition of polyphenol compounds in the ‘Regent’ must after UV-C exposure were evaluated. The viability of yeasts (Saccharomyces cerevisiae) and bacteria (Oenococcus oeni) significantly decreased with time; however, the highest decline was noted after the first hour of exposure. The polyphenol compound content was significantly lower after UV-C treatment and this was mainly the result of anthocyanin decomposition. The total content of flavan-3-ols and hydroxycinnamic acids and derivatives increased after irradiation.
2
Content available PANI/NaTaO3 composite photocatalyst for enhanced hydrogen generation under UV light irradiation
Zielińska B., Schmidt B., Mijowska E., Kaleńczuk R.
Polish Journal of Chemical Technology
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2017
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Vol. 19, nr 3
115--119
EN
A PANI/NaTaO3  composite was successfully synthesized by an oxidative polymerization of aniline monomer in hydrochloric acid solution containing sodium tantalate. NaTaO3  at a monoclinic structure was produced via hydrothermal method. The photocatalytic activities of the unmodified NaTaO3  and PANI/NaTaO3  were evaluated for hydrogen generation from an aqueous HCOOH solution and under UV light irradiation. The results showed that the evolution rate of H2  increased significantly when NaTaO3  was modified with PANI. The enhancement of the photocatalytic activity of PANI/NaTaO3  composite was ascribed to the effective charge transfer and separation between NaTaO3  and PANI, which reduced their recombination. This indicates that PANI modification of tantalate photocatalysts may open up a new way to prepare highly efficient catalytic materials for H2  generation.
3
Content available Monitoringowe badania źródeł Wyżyny Lubelskiej i Roztocza
Michalczyk Z., Chmiel S., Głowacki S., Zielińska B.
Przegląd Geologiczny
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2015
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Vol. 63, nr 10/2
935--939
EN
Next to the Tatra Mountains, the Lublin Upland and Roztocze Region are areas featuring the occurrence of the most efficient springs in Poland. They are particularly fed from the Cretaceous aquifer, only in the north-western part of the region also by waters circulating in the sediments of the Palaeocene, and in the boundary zone of Roztocze and Lublin Upland – Neogene. The earlier determination of occurrence of springs commenced in 1998, involving systematic measurements of approximately 70 selected springs. Monitoring measurements covered springs distributed in all of the physico-geographic regions with yield of more than 10 dm3/s. Measurements of the yield and physicochemical properties of water were performed annually in late spring. Data concerning 60 springs were compared for the period 1998–2014. The collected hydrometric materials permit the comparison of the dynamics of the yield and properties of water quality in both temporal and spatial terms. The mean spring yield amounted to 81.2 dm3/s. The mean value from the minimum yield decreased to 59.2 dm3/s, and from maximum increased to 132.7 dm3/s. The coefficient of yield irregularity varied from 1.6 to 5.9 for 90% of the analysed springs. Spring waters were distinguished by moderate mineralisation, reaction approximate to neutral, dominance of HCO3–Ca ions, and very high quality.
4
Content available Comparison of NaNbO3 and NaTaO3 as the photocatalysts in the reaction of hydrogen generation
Zielińska B., Kaleńczuk R. J. R. J.
Polish Journal of Chemical Technology
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2010
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Vol. 12, nr 3
33-35
EN
The photocatalytic production of hydrogen over several chemical compounds based on sodium niobates and tantalates has been investigated. The photocatalysts have been prepared by an impregnation method of Nb2O5and Ta2O5 in the aqueous solution of sodium hydroxide and then the calcination at the temperature range of 450 – 800°C. In this report, we present the study showing that of the catalysts explored, the highest photocatalytic activity was shown in a sample obtained at the temperature of 450°C and containing NaTaO3 as a main phase.
5
Content available remote A study on the synthesis, characterization and photocatalytic activity of TiO2 derived nanostructures
Zielińska B., Borowiak-Palen E., Kalenczuk R. J.
Materials Science Poland
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2010
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Vol. 28, No. 3
625--637
EN
Syntheses of TiO2 derived nanostructures have been conducted at 210 °C by hydrothermal reaction of commercial TiO2-P25 (Degussa, Germany) in 10 M NaOH aqueous solution. High purity of the asproduced material was confirmed by scanning and transmission electron microscope analyses. The crystallographic structure, as well as the optical and vibronic properties of this material were examined by X-ray diffraction, diffuse reflectance (DR) UV-Vis, resonance Raman spectroscopic methods, respectively. Detailed analysis of the phase composition revealed that the rod-like structures are made up of sodium tetratitanate (Na2Ti4O9). It was also observed that acid treatment of the material (hydrothermal reaction) led to a decrease in the diameters of the nanorods. Finally, the photocatalytic activity of the investigated nanostructures was examined, by observing the reaction photocatalytic decolourisation of two organic dyes (Reactive Red 198 and Reactive Black 5) under UV-light irradiation.
6
Content available Photocatalytic hydrogen generation over alkali niobates in the presence of organic compounds
Zielińska B., Sreńscek-Nazzal J., Kaleńczuk R.J.
Polish Journal of Chemical Technology
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2008
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Vol. 10, nr 4
1-3
EN
The photocatalytic efficiency of alkali niobate-based compounds (Li, Na, K) for hydrogen generation has been investigated. The systematic study showed that the highest photocatalytic activity was observed in the case of Na/Nb2O5 catalyst which contained sodium niobate (NaNbO3) phase and that the most efficient electron donor for hydrogen generation was formic acid. In addition, the effect of organic donor (HCOOH) concentration on the amount of the evolved hydrogen was studied.
7
Content available Changes of springs' yield of Lublin Upland and Roztocze Region in 1998-2008
Michalczyk Z., Chmiel S., Głowacki S., Zielińska B.
Journal of Water and Land Development
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2008
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no. 12
113-126
EN
Lublin Upland and Roztocze region are known for the occurrence of a large number of springs of high yield. These springs are fed mainly from Cretaceous or Tertiary water-bearing horizon. In order to determine variability of springs' yield, 61 selected springs were analysed in spring periods of the years 1998-2008. Collected hydrometric materials allowed for comparing average and extreme yield values of springs in various physiographic regions within the period of 11 years. Average value was 76.1 dm³ ·s-¹, while the mean of the minimal yields was 44.7 dm³ ·s-¹ and of the maximal - 132.7 dm³ ·s-¹. Coefficient of irregularity of the springs' yield ranged from 1.5 to 5.0, which may lead to the conclusion that the springs' yield is constant or varies slightly. In some cases the irregularity was higher but it was determined by hydrogeological, meteorological and local factors.
PL
W latach 1998-2008 wykonywano w okresach wiosennych pomiary wydajności 61 charakterystycznych źródeł Wyżyny Lubelskiej i Roztocza. Jest to obszar występowania najwydajniejszych, poza regionem tatrzańskim, źródeł w Polsce. Zebrane materiały hydrometryczne świadczą o istotnym regionalnym zróżnicowaniu warunków zasilania rzek wodami podziemnymi. Tylko pośrednio wskazują na zmienność warunków hydrogeologicznych regionu, którego cechą jest występowanie wydajnych żródeł o wydajności dochodzącej nawet do 400 dm³ ·s-¹. Wydajność źródeł w znacznym stopniu decyduje o zasobności w wodę rzek, które w okresie bezopadowym są zasilane wyłącznie z zasobów podziemnych. Minimalne odpływy jednostkowe ze zlewni rzek wyżynnych praktycznie nie zmniejszają się poniżej 1 dm³ ·s-¹ ·km-², co wskazuje na znaczne zasoby wód podziemnych. Zebrane jednorodne materiały hydrometryczne umożliwiają porównanie wydajności średnich i skrajnych w okresie 11 lat na zróżnicowanym fizjograficznie obszarze Wyżyny Lubelskiej i Roztocza. Średnia wydajność 61 mierzonych źródeł wynosiła 76,1 dm³ ·s-¹, natomiast średnia z minimalnych wydatków zmniejszyła się do 44,7 dm³ ·s-¹, a z maksymalnych zwiększyła do 132,7 dm³ ·s-¹. Zatem średni współczynnik nieregularności wydatku mierzonych źródeł wynosi tylko 3,0. Corocznie mierzone źródła dostarczały łącznie 4600 dm³ ·s-¹ wody. W 2000 r., gdy stany wody podziemnej były wysokie, łączna wydajność osiągnęła 7400 dm³ ·s-¹, a w 2004 r. obniżyła się do 3500 dm³ ·s-¹. W pierwszych latach pomiarów - do 2000 r. - wydajność źródeł się zwiększała. W następnych latach utrzymywała się ona na poziomie wartości średnich z wielolecia. Współczynnik nieregularności wydajności źródeł przyjmował przeważnie wartości w zakresie 1,5-5,0, w związku z czym można zaliczyć badane źródła do grupy wypływów o stałej i mało zmiennej wydajności. W kilku przypadkach nieregularność wydatku źródeł była większa, o czym decydowały warunki hydrogeologiczne i meteorologiczne oraz czynniki lokalne, między innymi związane z gospodarczym wykorzystaniem wody.
8
Preparation of Nb2O5 Photocatalysts Modified by Alkali Metals (Li, Na, K) and Its Photocatalytic Performance
Zielińska B., Arabczyk M.
Polish Journal of Chemistry
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2007
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Vol. 81, nr 7
1355-1362
EN
The paper reports the results of a preparation of photocatalysts based on niobium pentaoxide (Nb2O5). These materials have been obtained by calcination of a Nb2O5 precursor with alkali metal hydroxides (Li,Na, K). The obtainedmaterials have been characterized by several methods, i.e., XRD, DR-UV-vis, and FTIR/DRS. The photocatalytic decomposition of phenol as amodel contaminant has been investigated in the presence of all the prepared photocatalytic materials under UV-light irradiation. Of all investigated samples, Na/Nb2O5 has the highest activity.
9
Content available remote Photosensitized decomposition of textile dyes on TiO2-Tytanpol A11 and TiO2-Degussa P25
Zielińska B., Morawski A. W., Kaleńczuk R. J.
Polish Journal of Chemical Technology
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2006
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Vol. 8, nr 3
150-152
EN
The photoassisted decomposition of five organic dyes (Reactive Red 198 (RR198), Reactive Black 5 (RB5), Acid Black 1 (AB1), Direct Green 99 (DG99) and Acid Blue 7 (AB7)) has been investigated in aqueous solution in the presence of two kinds of TiO2 photocatalysts: TiO2-Tytanpol A11 (,,Police" Chemical Factory, Poland) and TiO2-Degussa P25 (,,Degussa" Germany) and under the illumination by the Vis light. The results suggest that the value of the adsorption of the dyes on the photocatalyst surface is the controlling step of the photosensitized degradation of dyes. The A11 photocatalyst demonstrates higher activity than P25. This effect is diffrent from the one obtained under the UV illumination, where P25 shows a much higher activity. Additionally, it was investigated that for both phototocatalysts used the degree of dyes decomposition decreased with the increasing of the maximum absorption of the dyes.
10
Fotokatalityczne usuwanie barwników organicznych z wody w obecności ditlenku tytanu, przy zastosowaniu reaktora z wewnętrznym źródłem promieniowania
Zielińska B., Morawski A. W.
Przegląd Włókienniczy - Włókno, Odzież, Skóra
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2005
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nr 5
37-40
11
Content available remote Badanie właściwości modyfikowanego ditlenku tytanu w reakcjach fotokatalitycznego rozkładu związków organicznych w wodzie
Zielińska B., Morawski A. W.
Gaz, Woda i Technika Sanitarna
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2004
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Nr 12
425-428
EN
Characteristics of photocatalysers. Photocatalytic reaction. Basic parameters characteristic of semi-conductive materials used in photo-catalytic processes.
12
Content available remote Photocatalytic degradation of reactive Black 5. A comparison between Ti02-Tytanpol All and TiO2-Degussa P25 photocatalysts
Zielińska B., Grzechulska J., Morawski A. W.
Polish Journal of Chemical Technology
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2001
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Vol. 3, nr 2
35-37
EN
Photocatalysts based on titanium dioxide were used for purification of organic pollutants in water. The photo-catalytic decomposition of Reactive Black 5, a textile azo dye, has been investigated in aqueous heterogeneous solution containing semiconductor oxides as photocatalyst. Two types of photocatalysts were used in the reaction: Tytanpol All produced on Polish market by Police company and the most popular titanium dioxide-P25 produced by Degussa Company. The effect of operational parameters, i. e. photocatalyst content, dye concentration, pH of solution on the photocatalytic decomposition of Reactive Black 5 in water has been examined. The photocatalytic decomposition of RB5 was about 30% lower for All than P25 in all cases.
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