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1

The importance of degradation in the fate of selected organic compounds in the environment. Part II. Photodegradation and biodegradation

100%
Dabrowski D., Kot-Wasik A., Namiesnik J.
Polish Journal of Environmental Studies
|
2004
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tom 13
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nr 6
Compounds characterized by a slow degradation rate in the environment, i.e. resistant to biodegradation, and photolysis processes, are classified as persistent and have often been considered as potential environmental problems. A more exacting approach recognizes that a compound released to the environment has a tendency to accumulate in one medium more than in others. Hence, partitioning, transport, and transformation rates of any particular compound will differ in each medium. Degradation processes in the dominant medium (where the compound is preferentially accumulated) are expected to have more effect on overall persistence of the measured compound than degradation processes in the other media. Photodegradation and biodegradation are the degradation processes which can naturaly clean up the environment. Biodegradation is expected to be the major mechanism of loss for most chemicals released into the environment. In this study, photodegradation and biodegradation processes of selected organic pollutants in different media have been reviewed.
2

Stability studies of selected polycyclic aromatic hydrocarbons in different organic solvents and identification of their transformation products

86%
Dabrowska D., Kot-Wasik A., Namiesnik J.
Polish Journal of Environmental Studies
|
2008
|
tom 17
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nr 1
17-24
One of the problems in an HPLC laboratory is the preservation of samples and extracts prior to analysis without any changes. It has been found that degradation processes cannot be eliminated entirely, but they can be slowed down considerably. Photodegradation kinetics of fluorene, anthracene and benzo(a)pyrene were studied in various organic solvents. Solvents known as good media to store PAHs for a long time were selected with respect to avoid degradation. In the case of fluorene, 9-fluorenone and 9-hydroxyfluorene were detected as main photoproducts. Formation of anthraquinone and 1,8-dihydroxyanthraquinone during the degradation of anthracene was observed. Benzo(a)pyrene-4,5-dihydrodiol and one of the isomers of hydroxy-BaP-dione as products of benzo(a)pyrene photodegradation have been identified.
3

Titanium dioxide and alpha-hydroxyacids in aqueous solutions and O-W emulsions

86%
Glowczyk-Zubek J., Kus S., Maslowska B., Nadir F.
Towaroznawcze Problemy Jakości. Polskie Towarzystwo Towaroznawcze
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2007
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nr 4
4
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Effect of oxygen on UV-induced photodegradation of humic acid obtained from composted hulls of Juglans regia walnut

86%
Slawinska D., Polewski K., Rolewski P., Slawinski J.
International Agrophysics
|
2004
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tom 18
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nr 2
5
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The significance of dissolved organic matter photodegradation as a source of ammonium in natural waters

72%
Grzybowski W.
Oceanologia
|
2002
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tom 44
|
nr 3
Samples of sea, river and pond water of different absorbance were exposed to artificial radiation resembling sunlight in the UV range. A statistically significant increase in ammonium concentration was detected in pond water of the highest absorbance after 5 h of irradiation. In sea and river water a corresponding increase (< 0.5 μM) was recorded after an exposure time of 25 hours. The bulk characteristics of the analysed samples were insufficient to explain the observed differences.
6

Sunlight-induced changes of biodegradability and absorbance of organic matter dissolved in the Gulf of Gdansk water

72%
Grzybowski W.
Polskie Archiwum Hydrobiologii
|
1999
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tom 46
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nr 2
7

Spectroscopic studies on UVC-induced photodegradation of humic acids

72%
Slawinska D., Polewski K., Rolewski P., Plucinski P., Slawinski J.
Electronic Journal of Polish Agricultural Universities. Series Environmental Development
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2002
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tom 05
|
nr 2
The effect of UV radiation on absorption, fluorescence spectra and dynamics of phototransformation of five different humic acids (HA) of natural and synthetic origin were investigated. Two types of synthetic HA were prepared: one containing only C, H and O atoms, and another with content of C, H, O and N atoms. Natural HA were also diversified with respect to their origin. We used UV-C radiation (predominantly the wavelength of 254 nm) to provide a wide spectrum of photochemical mechanisms.
8

Chemiluminescence imaging of the formation and photodegradation of humic acid derived from 5-hydroxy-1,4-naphthoquinone [juglone]

72%
Gorski Z., Rolewski P., Slawinska D., Slawinski J.
Electronic Journal of Polish Agricultural Universities. Series Environmental Development
|
2004
|
tom 07
|
nr 2
A new model humic acid (HA) have been synthetized from 5-hydroxy-1,4-naphthoquinone (juglone, J), an allelopathic compound occuring in leaves, nut shells, exsudates of roots and barks of Juglans genera. Aqueous solutions of J were autooxidised at different pH 6-10 with mineral matrices: bentonite, glass and silica. The very slow autooxidation reaction was monitored by means of chemiluminescence (CL) imaging and kinetics supported by a highly sensitive CCD camera Molecular Light Imager. In the course of autooxidation that lasted three weeks, an extremely low-intensity of CL was detected The reaction liquid was further treated according to the IHSS protocol to isolate humic acid fractions. Elemental analysis, UV-VIS and FTIR absorption spectra as well as fluorescence excitation and emission spectra were measured to characterise this new HA.
9
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Comparative studies of ipe (Tabebuia spp.) wood photodegradation cause by treatment with outdoor and indoor UV-A light irradation

58%
Zborowska M., Stachowiak-Wencek A., Waliszewska B., Pradzynski W.
Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology
|
2014
|
tom 88
Comparative studies of ipe (Tabebuia spp.) wood photodegradation cause by treatment with outdoor and indoor UV-A light irradiation. A study on photodegradation of ipe (Tabebuia spp.) wood by UV A light has been carried out. Two types of lamps were used in the tests, i.e. a UVA-340 lamp with a wavelength of 290 - 400 nm, emitting light resembling natural light, an a UVA-351 lamp with a wavelength of 300 - 400 nm, imitating light found indoors penetrating through window panes. Colour of the samples was measured using a Datacolour 600 spectrophotometer prior and after 1,5, 10, 25, 50 and 100-hour irradiation. Characterization of investigated material included determination of its chemical components. Despite the fact that ipe wood contains high concentrations of components playing an important role in the photodegradation process (e.g. 37.2% lignin) the detected changes are minor and do not exceed 1 point. The change in colour (∆E) for ipe wood surface was mainly caused by changes in the chromatic coordinate (b*) and the lightness coordinate (L*). Greater changes occurred under the influence of a UV-340 lamp emitting the type of light resembling that found outdoors.
10

Wplyw adiuwantow na fotodegradacje pendimetaliny w wodzie

58%
Swarcewicz M., Osumek R.
Progress in Plant Protection
|
2004
|
tom 44
|
nr 2
1127-1130
11
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Comparative studies of ipe (Tabebuia spp.) wood photodegradation caused by treatment with acid and alkaline buffers

58%
Zborowska M., Stachowiak-Wencek A., Waliszewska B., Pradzynski W.
Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology
|
2014
|
tom 88
Comparative studies of ipe (Tabebuia spp.) wood photodegradation caused by treatment with acid and alkaline buffers. A study on photodegradation of ipe wood using xenon lamp and UV lamp light has been carried out. Colour of the samples was measured using a Datacolour 600 spectrophotometer prior to their soaking in acid and alkaline buffers, after soaking and successively after 1, 5, 10, 25, 50 and 100-hour irradiation. It was concluded that the treatment with acid and alkaline buffers causes opposite changes of the investigated colour coordinates. Samples after treatment with the acid buffer were lighter and yellower in colour, but less red, while after treatment with the alkaline buffer they were darker and redder, bur less yellow. Generally treatment with the alkaline buffer caused more significant changes of ipe wood in comparison to treatment with the acid buffer. Samples treated with the acid buffer were more prone to changes of colour (∆E*) due to light irradiation in comparison to the samples treated with the alkaline buffer. More significant changes of colour were observed in the case of UV irradiation in comparison to irradiation cause by xenon lamp light.
12
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Wplyw procesow fotodegradacji i biodegradacji na wlasciwosci opakowaniowej folii z polietylenu

51%
Szostak-Kotowa J., Witalis J.
Żywność Nauka Technologia Jakość
|
1999
|
tom 06
|
nr 1
49-58
Folię opakowaniową z polietylenu poddano działaniu promieniowania UV oraz połączonemu wpływowi promieni UV i mikroflory glebowej. Stopień degradacji folii określano na podstawie zmian naprężenia maksymalnego przy zerwaniu. Otrzymane wyniki poddano analizie wariancji. Z przeprowadzonych badań wynika, że: 1) mikroflora gleby wpływa w sposób statystycznie istotny na degradację folii PE, naświetlanej uprzednio UV; 2) naprężenie maksymalne przy zerwaniu jest dobrą miarą zmian właściwości mechanicznych folii PE; 3) model regresyjny, w którym czas naświetlania występuje w postaci wielomianu stopnia trzeciego, najlepiej opisuje trójfazowe zmiany właściwości badanej folii pod wpływem promieni UV.
13

The combined effect of UV-radiation and soil microorganisms on the biodegradability of polyethylene package film with starch additive

51%
Szostak-Kotowa J., Witalis J.
Żywność Technologia Jakość. Suplement
|
1998
|
tom 05
|
nr 4
246-250
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