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Cycon M.,University of Silesia | Wojcik M.,Institute of Industrial Organic Chemistry | Borymski S.,University of Silesia | Piotrowska-Seget Z.,University of Silesia
Applied Soil Ecology | Year: 2013

Napropamide is one of the most commonly used herbicide in agricultural practice and its continuously application poses a potential risk for non-target soil microorganisms. Therefore, the objective of this study was to assess the impact of napropamide, applied at the field rate (FR, 2.25mgkg-1 of soil) and 10 times the FR (10*FR, 22.5mgkg-1 of soil) on soil microorganisms. To ascertain this impact, substrate-induced respiration (SIR), dehydrogenase (DHA), acid and alkaline phosphatases (PHOS-H and PHOS-OH), urease (URE) activities and changes in concentrations of NO3 - and NH4+ ions were determined. In addition, numbers of total bacteria and bacteria involved in soil nitrogen transformation were enumerated. A phospholipid fatty acid (PLFA) method was used to assess changes in the structure of soil microbial communities. Results showed negative effect of napropamide applied at the FR for SIR, the number of total bacteria, DHA, both PHOS, and URE at the beginning of the experiment. In 10*FR treated soil, a decreased activity of SIR, DHA, PHOS-OH and PHOS-H was observed over the experimental period. Nitrifying and N2-fixing bacteria appeared to be the most sensitive to napropamide. The concentration of NO3 - decreased in both napropamide-treated soils, whereas the concentration of NH4 + on day 28 in soil with 10*FR was 5 times higher than in the control. Analysis of the PLFA profiles showed that napropamide decreased the biomass of total, bacterial and fungal PLFAs on day 1, while at the end of the experiment in the soil treated with FR dosage of napropamide biomass of total, Gram-negative bacteria and fungi was significantly higher than those observed in the control. A principal component analysis of the PLFAs showed that napropamide application significantly shifted the microbial community structure on days 1 and 14. The degradation kinetics data showed that napropamide degradation by soil autochthonous microorganisms was relatively slow. The results indicated that a broad spectrum of analyze gives a better insight into the true effects of napropamide on soil microorganisms than the single assays. © 2013 Elsevier B.V.

Cycon M.,University of Silesia | Wojcik M.,Institute of Industrial Organic Chemistry | Piotrowska-Seget Z.,University of Silesia
Biodegradation | Year: 2011

Degradation of the fungicide thiophanate-methyl (TM) by Enterobacter sp. TDS-1 and Bacillus sp. TDS-2 isolated from sandy soil previously treated with TM was studied in mineral salt medium (MSM) and soil. Both strains were able to grow in MSM supplemented with TM (50 mg l-1) as the sole carbon source. Over a 16 days incubation period, 60 and 77% of the initial dose of TM were degraded by strains TDS-1 and TDS-2, respectively, and disappearance of TM was described by first-order kinetics. Medium supplementation with glucose markedly stimulated bacterial growth; while the final rate of TM degradation was reduced by 21 and 27% for strains TDS-1 and TDS-2, respectively as compared to medium with TM only. Moreover, this additional carbon source changed the TM degradation kinetics, which proceeded according to a zero-order model. This effect was linked to substrate competition and/or a strong decrease of medium pH. Isolates degraded TM (100 mg kg-1) in soil with rate constants of 0.186 and 0.210 day-1, following first-order rate kinetics, and the time in which the initial TM concentration was reduced by 50% (DT50) in soils inoculated with strains TDS-1 and TDS-2 were 6.3 and 5.1 days, respectively. Analysis of TM degradation products in soil showed that the tested strains may have the potential to transform carbendazim (MBC) to 2-aminobenzimidazole (2-AB), and may be useful for a bioremediation of MBC-polluted soils. © 2010 Springer Science+Business Media B.V.

Buczkowski D.,Institute of Industrial Organic Chemistry | Zygmunt B.,Military University of Technology
Central European Journal of Energetic Materials | Year: 2011

Detonation properties of mixtures of milled ammonium nitrate based fertilizers and fuels-aluminium or mineral oil-have been determined. The fertilizers used were ammonium nitrate and its compositions with mineral meal; for some compositions additional amount of mineral meal was mixed with the fertilizer. Detonation velocity, Guerney's energy and limits of detonability of such mixtures have been measured. It was examined that mixtures of mineral oil and fertilizers containing over 20% of mineral meal detonated during the tests. Mixtures of aluminium and fertilizers detonated even if concentration of mineral meal in the fertilizers was 40%.

Buczkowski D.,Institute of Industrial Organic Chemistry
Central European Journal of Energetic Materials | Year: 2014

The addition of many organic substances decreases the thermal stability and increases the explosive properties of ammonium nitrate(V). In order to determine how very material of plant origin would increase the risk of decomposition and explosion of ammonium nitrate(V), tests using the DTA method and the detonation properties were performed. The materials tested were milled ammonium nitrate(V) mixed with wheat flour, hard coal, rape seeds or wood dust. It was found that all of the mixtures tested decompose at significantly lower temperatures than ammonium nitrate(V) and ANFO explosive. Some of them decompose close to the melting temperature of ammonium nitrate(V) and their decomposition is violent. All of the mixtures tested are cap sensitive and some of them have smaller critical diameters than ANFO. The detonation velocities of the mixtures are lower than the detonation velocity of ANFO, but significantly higher than that of ammonium nitrate(V).

Kwiatkowska M.,University of Lodz | Huras B.,Institute of Industrial Organic Chemistry | Bukowska B.,University of Lodz
Pesticide Biochemistry and Physiology | Year: 2014

The toxicity of herbicides to animals and human is an issue of worldwide concern. The present study was undertaken to evaluate toxic potential of widely used pesticide - glyphosate, its metabolites: aminomethylphosphonic acid (AMPA); methylphosphonic acid and its impurities: N-(phosphonomethyl)iminodiacetic acid (PMIDA), N-methylglyphosate, hydroxymethylphosphonic acid and bis-(phosphonomethyl)amine. We evaluated the effect of those compounds on hemolysis, hemoglobin oxidation, reactive oxygen species (ROS) formation and changes in morphology of human erythrocytes. The erythrocytes were exposed to different concentrations of glyphosate and its metabolites and impurities (0.01-5. mM) for 1, 4 and 24 h. Glyphosate, its metabolites and impurities induced a little hemolysis and hemoglobin oxidation. All changes were very low, even after 24 h incubation. Most of the investigated compounds induced reactive oxygen species formation from 0.25. mM, except the N-methylglyphosate which caused an increase in ROS formation from 0.5. mM. Moreover, the investigated xenobiotics did not change the size and shape (except bis-(phosphonomethyl)amine) of the human erythrocytes. Changes in human erythrocytes were observed only when high concentrations of the compounds were applied. Some investigated metabolites and impurities caused a slight stronger damage to human erythrocytes than a glyphosate. The results clearly show that the changes induced in the erythrocytes can occur only as a result of poisoning with these compounds. © 2014 Elsevier Inc.

The Morita-Baylis-Hillman adducts bearing a nitroxyl moiety were synthesized from 4-acryloyloxy-2,2,6,6-tetramethylpiperidine- 1-oxyl and aliphatic, aryl and heterocyclic aldehydes. © 2012 Zakrzewski; licensee Beilstein-Institut.

Bin A.K.,Warsaw University of Technology | Sobera-Madej S.,Institute of Industrial Organic Chemistry
Ozone: Science and Engineering | Year: 2012

The effectiveness of UV-based processes (UV and UV/H 2O 2) for the treatment of pharmaceuticals wastewater was investigated and compared with the effects of simple ozonation. Degradation of the studied antibiotic wastewater by direct photolysis indicated that, without application of additional factors, the process is not very effective, transferring the fate of antibiotics to the environment. For the studied antibiotic, wastewater ozonation was found to be the most effective among the three tested AOPs. © 2012 Copyright 2012 International Ozone Association.

Zakrzewski J.,Institute of Industrial Organic Chemistry | Krawczyk M.,Institute of Industrial Organic Chemistry
Bioorganic and Medicinal Chemistry Letters | Year: 2011

The antifungal activity of nitroxyl radicals - derivatives of 2,2,6,6-tetramethylpiperidine-1-oxyl with reactive substituents 4-isothiocyanato-, 4-isocyano-, and 4-isoselenocyanato- and of N-formyl-, N-thioformyl-, N-selenoformyl-derivatives of 2,2,6,6-tetramethylpiperidine was investigated. Those of the above compounds, which contain a sulfur or selenium atom are the most active against four fungus plant patogens: Botrytis cinerea, Fusarium culmorum, Phytophthora cactorum, Rhizoctonia solani. 4-Isoselenocyanato-2,2,6,6-tetramethylpiperidine-1-oxyl proved to be the most active compound. © 2010 Elsevier Ltd. All rights reserved.

Gucma M.,Institute of Industrial Organic Chemistry | Golebiewski W.M.,Institute of Industrial Organic Chemistry | Krawczyk M.,Institute of Industrial Organic Chemistry
RSC Advances | Year: 2015

Chiral Lewis acid mediated 1,3-dipolar cycloaddition reactions of 4-trifluoromethylbenzonitrile oxide to methyl crotonate as well to β-substituted acrylates and (Z)-pent-2-en-1-yl esters were examined. Excellent enantioselectivities with moderate to good regioselectivities were achieved for crotonates with complexes of BiBr3 with (+)-(4,6-benzylidene)methyl-α-d-glucopyranoside C, with the l-ascorbic acid I-FeCl3 system, and with lipase Candida antarctica. High enantiomeric excess was observed for isopropyl ester and benzyl ester. The outstanding ee values were achieved for acrylates with β-t-butyl, cyclohexyl, and 1,3-benzodioxol-5-yl groups in cycloadditions catalyzed by C-Yb(OTf)3 and the (+)-2-hydroxy-3-pinanone N-TiCl4 system. High enantioselectivities were found in reactions of (Z)-pent-2-en-1-yl esters mediated by complexes N-Mg(OTf)2 and N-TiCl4. © The Royal Society of Chemistry 2015.

Zalewski R.,Warsaw University of Technology | Wolszakiewicz T.,Institute of Industrial Organic Chemistry
Central European Journal of Energetic Materials | Year: 2011

The main object of this paper is to reveal basic response of solid rocket fuels to different working conditions such as variable strain rates or temperature. Experimental data acquired during experimental tests is a base for development of a suitable constitutive model for homogeneous solid propellants. In the world literature there is still insufficient information about typical mechanical features for considered materials. Universal standards for carrying out typical strength experiments have not yet been fully elaborated for this type of materials. Such problems as quasi-static strain range for solid propellants or so called scale effect are still not standardized. Though, this paper is a next step in preliminary investigation devoted to modeling of nonlinear properties of solid propellants. In particular, the influence of temperature and strain rate on selected mechanical parameters variations is discussed.

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