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  • 1
    Language: English
    In: Chemosphere, Jan, 2014, Vol.95, p.470(8)
    Description: To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.chemosphere.2013.09.100 Byline: Stephan Sittig, Roy Kasteel, Joost Groeneweg, Diana Hofmann, Bjorn Thiele, Stephan Koppchen, Harry Vereecken Abstract: acents We show transformation and sequestration of the antibiotic sulfadiazine in two soils. acents Transformation products were found in liquid phase and extracts from the sorbed phase. acents We used a compartment model including all species and did global optimization. acents Sorption and transformation are concentration dependent. Article History: Received 12 December 2012; Revised 21 September 2013; Accepted 29 September 2013
    Keywords: Soils ; Sulfadiazine
    ISSN: 0045-6535
    Source: Cengage Learning, Inc.
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  • 2
    Language: English
    In: Chemosphere, 2011, Vol.84(4), pp.409-414
    Description: ► The sorption of a branched nonylphenol isomer (NP111) on humic acids was investigated by a dialysis technique. ► Humic acids were characterized by solid-state C DP/MAS NMR spectroscopy. ► A relationship between the organic carbon-normalized sorption coefficients of NP111 and the aliphaticity of humic acids was established. By using dialysis equilibrium experiments, the sorption of a branched nonylphenol isomer [4-(1-ethyl-1,3-dimethylpentyl)-phenol] (NP111) on various humic acids (HAs) isolated from river sediments and two reference HAs was studied. The HAs were characterized by solid-state C direct polarization/magic angle spinning nuclear magnetic resonance ( C DP/MAS NMR) spectroscopy. Sorption isotherms of NP111 on HAs were described by a linear model. The organic carbon-normalized sorption coefficient ( ) ranged from 2.3 × 10 to 1.5 × 10 L kg . Interestingly, a clear correlation between value and alkyl C content was observed, indicating that the aliphaticity of HAs markedly dominates the sorption of NP111. These new mechanistic insights about the NP111 sorption indicate that the fate of nonylphenols in soil or sediment depends not only on the content of HA, but also on its structural composition.
    Keywords: Branched Nonylphenol ; Sorption ; Humic Acids ; NMR ; Aliphaticity ; Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 3
    Language: English
    In: Chemosphere, Sept, 2010, Vol.81(1), p.1321(7)
    Description: To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.chemosphere.2010.06.046 Byline: Jing Zhang, Jean-Marie Sequaris, Hans-Dieter Narres, Harry Vereecken, Erwin Klumpp Keywords: Nonlinear sorption; Pyrene; Black carbon; Sediment; Polanyi; Fluorescence Abstract: The effect of organic carbon (OC) and mineral surface on the sorption of polycyclic aromatic hydrocarbon (PAH) pyrene molecule to four Yangtze River sediments was investigated by sorption batch techniques using fluorescence spectroscopy. Pyrene sorption to the mineral fraction was estimated with model sorbent illite, the main clay mineral in Yangtze sediment. The Freundlich model fitted sorption to illite and to sediments was normalized to the specific surface area (SSA). Comparison of the SSA-normalized sorption capacities of illite and sediments suggests a negligible contribution of the pyrene sorption to the mineral fraction. In addition, composite models, such as the linear Langmuir model (LLM) and the linear Polanyi-Dubinin-Manes model (LPDMM) were applied for fitting the sorption of pyrene to the pristine sediments. The application of composite models allows assessing the partition of pyrene into amorphous organic carbon (AOC) and the adsorption in the porous structure of black carbon (BC). The modelling results indicate that the pyrene adsorption to the minor BC components (〈0.2%) is more effective than the partition to AOC (0.5-1.3%). Besides the pristine sediments, sediments preheated at 375[degrees]C were also studied, in which the AOC fraction was removed during the preheating treatment. The modelling results with LPDMM and Polanyi-Dubinin-Manes model (PDMM) indicate a similar adsorption capacity of BC in pristine and preheated sediments, respectively. The low AOC concentrations in sediments do not diminish the BC micropore filling with pyrene. Simulation of pyrene distribution in the investigated Yangtze River sediments support the importance of the BC fraction in the PAH immobilization under environmental conditions. Author Affiliation: Agrosphere, ICG 4, Forschungszentrum Julich GmbH, D-52425 Julich, Germany Article History: Received 19 March 2010; Revised 2 June 2010; Accepted 9 June 2010
    Keywords: Clay Minerals -- Analysis ; Polycyclic Aromatic Hydrocarbons -- Analysis ; Adsorption -- Analysis ; River Sediments -- Analysis ; Clay -- Analysis
    ISSN: 0045-6535
    Source: Cengage Learning, Inc.
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  • 4
    Language: English
    In: Chemosphere, April 2017, Vol.172, pp.310-315
    Description: The soil-plant transfer of Cs-137 and Sr-90 in different crops was determined with respect to the present-day amendment practice of using digestate from biogas fermenters. The studies were performed using large lysimeters filled with undisturbed luvisol monoliths. In contrast to the conservative tracer, Br , neither of the studied radionuclides showed a significant vertical translocation nor effect of the applied digestate amendment compared to a non-amended control was found. Furthermore, no significant plant uptake was measured for both nuclides in wheat or oat as indicated by the low transfer factors between soil-shoot for Cs-137 (TF 0.001–0.010) and for Sr-90 (0.10–0.51). The transfer into nutritionally relevant plant parts was even lower with transfer factors for soil-grain for Cs-137 (TF 0.000–0.001) and for Sr-90 (0.01–0.06). Hence, the amendment with biogas digestate is unfortunately not an option to further reduce plant uptake of these radionuclides in agricultural crops, but it does not increase plant uptake either.
    Keywords: Radioactive Contaminants ; Undisturbed Soil Monolith ; Agro-Ecosystem ; Oat ; Wheat ; Transfer Factor ; Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 5
    Language: English
    In: Chemosphere, January 2014, Vol.95, pp.470-477
    Description: Veterinary antibiotics administered to livestock can be unintentionally released into the environment, for example by the application of manure to soils. The fate of such antibiotics in soils is mostly determined by sorption and degradation processes, including transformation. There is a need to further examine the combined transformation and sorption behavior of these emerging pollutants in soils. Long-term batch sorption experiments with the C-radiolabeled antibiotic sulfadiazine enabled us to simultaneously trace the sorption and transformation dynamics of sulfadiazine. The parent compound and the transformation products were analyzed in the liquid phase and in the extracts from the solid phase after a sequential extraction. We found that of up to six transformation products were formed during degradation and that these products exhibited quite different dynamics in the two soils. Transformation products were formed rapidly and were extractable from the solid phase. We observed identical sets of the transformation products in both phases. The input concentration influenced the course of transformation of the parent substance. We present a detailed analysis including a mathematical description and derive regulatory kinetic endpoints for predicting environmental concentrations.
    Keywords: Sulfadiazine ; Transformation in Soils ; Sorption and Sequestration ; Numerical Studies ; Kinetic Endpoints ; Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 6
    Language: English
    In: Chemosphere, 2010, Vol.80(11), pp.1321-1327
    Description: The effect of organic carbon (OC) and mineral surface on the sorption of polycyclic aromatic hydrocarbon (PAH) pyrene molecule to four Yangtze River sediments was investigated by sorption batch techniques using fluorescence spectroscopy. Pyrene sorption to the mineral fraction was estimated with model sorbent illite, the main clay mineral in Yangtze sediment. The Freundlich model fitted sorption to illite and to sediments was normalized to the specific surface area (SSA). Comparison of the SSA-normalized sorption capacities of illite and sediments suggests a negligible contribution of the pyrene sorption to the mineral fraction. In addition, composite models, such as the linear Langmuir model (LLM) and the linear Polanyi–Dubinin–Manes model (LPDMM) were applied for fitting the sorption of pyrene to the pristine sediments. The application of composite models allows assessing the partition of pyrene into amorphous organic carbon (AOC) and the adsorption in the porous structure of black carbon (BC). The modelling results indicate that the pyrene adsorption to the minor BC components (〈0.2%) is more effective than the partition to AOC (0.5–1.3%). Besides the pristine sediments, sediments preheated at 375 °C were also studied, in which the AOC fraction was removed during the preheating treatment. The modelling results with LPDMM and Polanyi–Dubinin–Manes model (PDMM) indicate a similar adsorption capacity of BC in pristine and preheated sediments, respectively. The low AOC concentrations in sediments do not diminish the BC micropore filling with pyrene. Simulation of pyrene distribution in the investigated Yangtze River sediments support the importance of the BC fraction in the PAH immobilization under environmental conditions.
    Keywords: Nonlinear Sorption ; Pyrene ; Black Carbon ; Sediment ; Polanyi ; Fluorescence ; Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 7
    Language: English
    In: Chemosphere, August 2008, Vol.72(10), pp.1448-1454
    Description: In the environment, the sorption and the degradation of organic pollutants are of increasing interest. The investigation of the chemical structures provides a basis for the development of a suitable binding model approach and for the mechanistic understanding of the chemical fate processes. The aim of this study was the identification of different species of the antibiotic compound sulfadiazine (SDZ) using H and C NMR experiments and ab initio density functional theory (DFT) calculations. In the neutral, aprotic solvent dimethylsulfoxide- (DMSO- ), a new sulfadiazine structure containing an O–H–N hydrogen bond was identified. In the protic solvent water- and in dependence on pH and the position of the amidogen hydrogen atom nine possible SDZ conformations were analyzed and five structures were identified. Good conformity between theory and calculation of H NMR was observed. Unfortunately, C NMR is not sensitive enough for comparison and differentiation. In order to verify the identified structures, additional NBO/NLMO (natural localized molecular orbital) analyses were conducted (calculation of net atomic charges, bond polarity, atomic valence, and electron delocalization). Finally, conformation optimizations were performed in order to investigate the stability of the SDZ species. We showed that SDZ contains no S O double bond, but that it has two S–O single bonds. Surprisingly, negative charges were observed at the pyrimidine nitrogen atom. With these results, the known structure of SDZ was revised. Studies of the geometrical structure and the torsion angles showed that SDZ is very flexible and can be easily fitted to the sorbent. These observations would explain the strong sorbance and hence the rapid formation of non-extractable residues in the environment because SDZ acts as a strong ligand. These results show that that the sulfonamide hydrogen is important for the biological activity but the pyrimidine nitrogen and the sulfonamide oxygen is responsible for the sorbance in environment.
    Keywords: Sulfadiazine ; NMR ; Structure Elucidation ; Antibiotic ; Sulfonamide ; Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 8
    Language: English
    In: Chemosphere, 2008, Vol.72(5), pp.836-843
    Description: The ionic speciation of sulfonamides is pH-driven and this may be crucial for their bioavailability and sorption to soil constituents, as well as for their uptake into bacterial cells. The inhibition behaviour of a bacterial test strain ( DSM 1117), which was grown in the presence of different concentrations of 8 sulfonamides at pH values from 5 to 8, could be predicted by models that take the speciation of sulfonamides in- and outside of bacterial cells into account. Assuming a pH of 7.5 inside the cells (pH homeostasis), the strongest inhibition was predicted for the lowest external pH and for sulfonamides with the lowest p values. Growth experiments with basically reflected this predicted behaviour. However, – a bacterial strain isolated from arable soil – behaved surprisingly different regarding its pH dependency: all sulfonamides showed the strongest effects at pH 7 to 8 instead of being most effective at lowest pH, although the p dependencies followed the same pattern. Experimental and modeling results could be brought into good agreement for if the cell-internal pH was admitted to approximate the external pH instead of implying pH homeostasis for modeling calculations. Thus, besides the actual concentration of sulfonamides, the pH dependent mode of reaction of different bacteria to sulfonamides may additionally govern the population dynamics in soils.
    Keywords: Antimicrobials ; Toxicity ; Ph Homeostasis ; Speciation ; EC 50 ; Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 9
    Language: English
    In: Chemosphere, 2008, Vol.72, pp.836-843
    Description: Includes references ; p. 836-843.
    Keywords: Soil Bacteria ; Microbial Growth ; In Vitro Studies ; Pantoea Agglomerans ; Sulfonamides ; Dosage ; Homeostasis ; Reaction Kinetics ; Simulation Models ; Species Differences ; Chemical Concentration ; Chemical Speciation ; Pseudomonas Aeruginosa ; Population Dynamics ; Ph ; Acid Dissociation Constant ; Effective Concentration 50
    ISSN: 0045-6535
    Source: AGRIS (Food and Agriculture Organization of the United Nations)
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  • 10
    Language: English
    In: Chemosphere, 1997, Vol.35(11), pp.2563-2587
    Description: The performance of simulation models to predict the amount of leached water, pesticide concentrations in soil and pesticide concentrations in the leachate from 39 lysimeters columns with undisturbed soil cores is described in this paper. The behaviour of 14 pesticides plus 1 metabolite was investigated mainly on loamy sand soils at four different locations in Germany. In three lysimeter studies a silty loam soil was used. The annual amount of precipitation ranged from 706 mm to 1393 mm (rainfall plus additional irrigation), 85% of the experiments received a minimum precipitation of 800 mm. The K sub(OC) values of the pesticides were between 5 and 4000, the mean DT sub(50) values in soil ranged from 5 to 120 days. The model calculations were performed with three different computer models: PRZM-1, PELMO 1.5 and PELMO 2.0.
    Keywords: Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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