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1.
Ralf-Dieter Zimmermann Rosemarie Umlauff-Zimmermann 《Umweltwissenschaften und Schadstoff-Forschung》2000,12(6):307-309
Einführung Beitragsserie POPs
Persistente Organische Schadstoffe Persistent Organic Pollutants, POPs 相似文献2.
Methoden
Zur Bewertung der gemessenen Schwermetallbelastungen des Bodens wurden sog. Risiko-Kennlinien für die Metalle Blei, Cadmium, Kupfer, Nickel und Zink entwickelt, die eine einheitliche Charakterisierung von Bodengehalten im Hinblick auf ihre Wirkung auf den Regenwurm sowie auf naturr?umliche Gegebenheiten erm?glichen. Die Mobilit?t der Metalle, die für die biologische Wirkung entscheidender ist als der Gesamtgehalt im Boden, wurde bei der Bewertung berücksichtigt. 相似文献3.
Sun J Song M Feng J Pi Y 《Environmental science and pollution research international》2012,19(5):1536-1543
Introduction
In this study, UV/Oxone/Co2+ oxidation process was applied to degradation of ofloxacin (OFL) in the presence of Co2+ as the catalytic and Oxone as the oxidant. The operation parameters including pH, temperature, dosages of reagents, and reaction time were studied in detail.Results
The results showed that the optimum conditions for the UV/Oxone/Co2+ processes were determined as follows: temperature?=?25°C, pH?=?5.0, [Oxone]?=?0.6?mmol/L, [Oxone]/[Co2+]?=?1,000, and reaction time?=?60?min. Under these conditions, 100% of the OFL degraded. The kinetics was also studied, and degradation of OFL by the UV/Oxone/Co2+ process could be described by first-order kinetics.Conclusions
Mineralization of the process was investigated by measuring the total organic carbon (TOC), and the TOC decreased by 87.0% after 60?min. This process could be used as a pretreatment method for wastewater containing ofloxacin. 相似文献4.
Ziel und Absicht
Durch atmosph?rische Deposition gelangen polyzyklische aromatische Kohlenwasserstoffe (PAK) auch in industriefernen Regionen in B?den und Sedimente. Als persistente organische Verbindungen (POP) k?nnen sie dort akkumulieren. ?hnliche PAK-Verteilungsmuster der atmosph?rischen Deposition, Boden- und Sedimentproben weisen auf einen engen Zusammenhang zwischen dem Eintrag aus der Luft und der Akkumulation dieser Substanzen in terrestrischen ?kosystemen hin. Ziel dieses Beitrages ist es zum einen, die aktuellen Boden-Hintergrundkonzentrationen im l?ndlichen Raum auf die atmosph?rische Deposition zu beziehen. Des weiteren wird mit einem einfachen Sch?tzverfahren ermittelt, wann mit überschreitungen der Vorsorgewerte nach Bundes-Bodenschutz-und Altlastenverordnung (BBodSchV) im l?ndlichen Raum zu rechnen ist. Dies wird im Kontext der aktuellen Umweltgesetzgebung diskutiert. 相似文献5.
?árka Pau?ová Josef Krysa Jaromír Jirkovsky Gilles Mailhot Vanessa Prevot 《Environmental science and pollution research international》2012,19(9):3709-3718
Introduction
Efficient immobilization of TiO2 nanoparticles on the surface of Mg2Al-LDH nanosheets was performed by delamination/restacking process.Experimental part
The structural and textural properties of as-prepared nanocomposite were deeply analyzed using different solid-state characterization techniques such as: X-ray powder diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopies, chemical analysis, X-ray photoelecton spectroscopy, N2 adsorption?Cdesorption, and electronic microscopy.Results and discussion
The photocatalytic properties of immobilized TiO2 nanoparticles on Mg2Al were investigated using the photodegradation of two model pollutants: Orange II and 4-chlorophenol, and compared with pure colloidal TiO2 solution.Conclusion
It appears that Orange II photodegradation was systematically faster and more efficient than 4-chlorophenol photodegradation regardless of the medium pH. Moreover under slightly basic conditions, even if the TiO2 photocatalytic efficiency decreases, photodegradation performed in presence of easily recovered TiO2/Mg2Al1.5 nanocomposite gives rise to comparable or better results than pure TiO2. 相似文献6.
Adsorption of Pb,Cd, Cu,Zn, and Ni to titanium dioxide nanoparticles: effect of particle size,solid concentration,and exhaustion 总被引:2,自引:1,他引:1
Karen E. Engates Heather J. Shipley 《Environmental science and pollution research international》2011,18(3):386-395
Purpose
Adsorption of metals (Pb, Cd, Cu, Ni, Zn) to TiO2 nanoparticles and bulk particles was examined for use as a contaminant removal substrate as a function of particle size, sorbent concentration, and exhaustion. 相似文献7.
Bandala ER Andres-Octaviano J Pastrana P Torres LG 《Journal of environmental science and health. Part. B》2006,41(5):553-569
Degradation of aldrin (1,2,3,4,10,10-Hexachloro-1,4,4a,5,8,8a-hexahydro-1,4:5-8-dimethanonaphthalene), heptachlor (1H-1,4,5,6,7,8,8-heptachloro-3a,4,7,7a-tetrahydro-4,7-methano indene), dieldrin (1aalpha,2beta,2aalpha,3beta,6beta,6aalpha,7beta,7aalpha)-3,4,5,6,9,9-Hexachloro-1a,2,2a,3,6,6a,7,7a-octahydro-2,7:3,6-d-methanonaphtha[2,3-b]oxirene, and heptachlor epoxide (1aalpha, 1bbeta,2alpha,5alpha,5alphabeta,6beta,6aalpha-2,3,4,5,6,7,7-Heptachloro-1a,1b,5,5a,6,6a-hexahydro-2,5-methano-2H-inden[1,2-b]-oxirene) was tested using free cultures of Pseudomonas fluorescens under controlled conditions. Pesticide concentrations were monitored by gas chromatography during 120 h. Percentages of degradation and biodegradation rates (BDR) were calculated. Data showed a trend suggesting a relation between chemical structure and degradability. Degradation kinetics for each pesticide tested showed that the highest degradation rates were found in the first 24 h. Kinetics data were adjusted to an empirical equation in order to predict their behavior, and the correlation coefficients obtained were satisfactory. Gas chromatography/mass spectrometry (GC/MS) analysis of the final extracts allowed the identification of chlordene and monodechlorodieldrin, which have been reported as final metabolite produced in the biodegradation of this kind of compounds. Regarding adsorption of pesticides on activated vegetal carbon, we concluded that removal efficiencies between 95.45 and 97.18% can be reached, depending on the pesticide and the carbon dose applied. The values for K from the Freundlich equation were quite similar for the four pesticides (between 1.0001 and 1.04), whereas the n values were quite different for each pesticide in the following order of affinity: dieldrin > aldrin > heptachlor epoxide > heptachlor. Equilibrium times, very important for scaling up the process, were between 43 min and 1 h, for the heptachlor epoxide and the heptachlor, respectively. 相似文献
8.
Background
In this study, manganese dioxide-coated multiwall carbon nanotube (MnO2/CNT) nanocomposite has been successfully synthesized. 相似文献9.
Adsorption of Remazol Red 198 onto magnetic N-lauryl chitosan particles: equilibrium, kinetics, reuse and factorial design 总被引:1,自引:0,他引:1
Debrassi A Baccarin T Demarchi CA Nedelko N Ślawska-Waniewska A Dłużewski P Bilska M Rodrigues CA 《Environmental science and pollution research international》2012,19(5):1594-1604
Purpose
The discharge of colored effluents from industries is an important environmental issue and it is indispensable to remove the dyes before the water gets back to the rivers. The magnetic adsorbents present the advantage of being easily separated from the aqueous system after adsorption by positioning an external magnetic field.Methods
Magnetic N-lauryl chitosan (L-Cht/??-Fe2O3) particles were prepared and characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy, and vibrating sample magnetometry. Remazol Red 198 (RR198) was used as a reactive dye model for adsorption on L-Cht/??-Fe2O3. The adsorption isotherms were performed at 25°C, 35°C, 45°C, and 55°C and the process was optimized using a 23 factorial design (analyzed factors: pH, ionic strength, and temperature). The desorption and regeneration studies were performed in a three times cycle.Results
The characterization of the material indicated that the magnetic particles were introduced into the polymeric matrix. The pseudo-second order was the best model for explaining the kinetics and the Langmuir?CFreundlich was the best-fitted isotherm model. At room temperature, the maximum adsorption capacity was 267?mg?g?1. The material can be reused, but with a decrease in the amount of adsorbed dye.Conclusions
L-Cht/??-Fe2O3 is a promising material to remove RR198 and probably other similar reactive dyes from aqueous effluents. 相似文献10.
Heterogeneous photocatalytic degradation of methyl orange in schwertmannite/oxalate suspension under UV irradiation 总被引:1,自引:0,他引:1
Wu Y Guo J Jiang D Zhou P Lan Y Zhou L 《Environmental science and pollution research international》2012,19(6):2313-2320
Introduction
Schwertmannite was synthesized through an oxidation of FeSO4 by Acidithiobacillus ferrooxidans LX5 cell suspension at an initial pH?2.5 and 28°C for 3?days and characterized using X-ray diffraction spectroscopy and scanning electron microscope. The schwertmannite photocatalytic degradation of methyl orange (MO) by oxalate was investigated at different initial pH values, concentrations of schwertmannite, oxalate, and MO.Results
The results demonstrated that photodegradation of MO in the presence of schwertmannite or oxalate alone was very weak. However, the removal of MO was significantly enhanced when schwertmannite and oxalate coexisted in the reaction system. Low pH (4 or less) was beneficial to the degradation of MO. The optimal doses of schwertmannite and oxalate were 0.2?g?L?1 and 2?mM, respectively. Hydroxyl radicals (·OH) and Fe(II), the intermediate products, were also examined during the reaction to explore their correlation with the degradation of MO.Conclusion
A possible mechanism for the photocatalytic decomposition of MO in the study was proposed. The formation of Fe(III)-oxalate complexes on the surface of schwertmannite was a precursor of H2O2 and Fe(II) production, further leading to the yield of ·OH responsible for the decomposition of MO. 相似文献11.
C. Montero-Ocampo A. Gago G. Abadias B. Gombert N. Alonso-Vante 《Environmental science and pollution research international》2012,19(9):3751-3762
Introduction
In this work, we report in situ studies of UV photoelectrocatalytic discoloration of a dye (indigo carmine) by a TiO2 thin film in a microreactor to demonstrate the driving force of the applied electrode potential and the dye flow rate toward dye discoloration kinetics.Methods
TiO2 65-nm-thick thin films were deposited by PVD magnetron sputtering technique on a conducting glass substrate of fluorinated tin oxide. A microreactor to measure the discoloration rate, the electrode potential, and the photocurrent in situ, was developed. The dye solutions, before and after measurements in the microreactor, were analyzed by Raman spectroscopy.Results
The annealed TiO2 thin films had anatase structure with preferential orientation (101). The discoloration rate of the dye increased with the applied potential to TiO2 electrode. Further, acceleration of the photocatalytic reaction was achieved by utilizing dye flow recirculation to the microreactor. In both cases the photoelectrochemical/photocatalytic discoloration kinetics of the dye follows the Langmuir?CHinshelwood model, with first-order kinetics.Conclusions
The feasibility of dye discoloration on TiO2 thin film electrodes, prepared by magnetron sputtering using a flow microreactor system, has been clearly demonstrated. The discoloration rate is enhanced by applying a positive potential (E AP) and/or increasing the flow rate. The fastest discoloration and shortest irradiation time (50?min) produced 80% discoloration with an external anodic potential of 0.931?V and a flow rate of 12.2?mL?min?1. 相似文献12.
Lützhøft HC Donner E Wickman T Eriksson E Banovec P Mikkelsen PS Ledin A 《Environmental science and pollution research international》2012,19(4):1119-1130
Purpose
Implementation of current European environmental legislation such as the Water Framework Directive requires access to comprehensive, well-structured pollutant source and release inventories. The aim of this work was to develop a Source Classification Framework (SCF) ideally suited for this purpose.Methods
Existing source classification systems were examined by a multidisciplinary research team, and an optimised SCF was developed. The performance and usability of the SCF were tested using a selection of 25 chemicals listed as priority pollutants in Europe.Results
The SCF is structured in the form of a relational database and incorporates both qualitative and quantitative source classification and release data. The system supports a wide range of pollution monitoring and management applications. The SCF functioned well in the performance test, which also revealed important gaps in priority pollutant release data.Conclusions
The SCF provides a well-structured approach for European pollutant source and release classification and management. With further optimisation and demonstration testing, the SCF has the potential to be fully implemented throughout Europe.13.
Cubero-Leon E Ciocan CM Minier C Rotchell JM 《Environmental science and pollution research international》2011,19(7):2728-2733
Purpose
The aim of this study is to develop a normalization method for real-time PCR data by analyzing the most stably expressed control genes in mussel (Mytilus edulis) reproductive tissue.Methods
To facilitate this, six candidate genes, including several commonly used in the literature, were investigated in mussels at different stages of gametogenesis and following experimental exposure to a model estrogen (17b-estradiol). GeNorm and NormFinder softwares were employed to assess the stability of the reference genes.Results
Our results demonstrate that the most stable reference genes are not the same in mussels at different stages of gametogenesis and in experimentally E2-exposed mussels. Interestingly, HEL (helicase) and ACT (actin) mRNA expression levels were most affected by the stage of gametogenesis and yet, in molluscan studies, ACT is possibly the most frequently used reference gene.Conclusions
We demonstrate that the experimental results are highly dependent on the reference gene chosen and that statistically significant contrasting differences between sample groups are present or absent depending on the reference gene employed. 相似文献14.
Rais Ahmad Rajeev Kumar Mohammad Asaduddin Laskar 《Environmental science and pollution research international》2013,20(1):219-226
Background
The adsorption characteristics of Pb2+ ions from aqueous solutions onto calix[4]naphthalene have been investigated.Method
Calix[4]naphthalene was prepared by the condensation of 1-naphthol and formaldehyde (1:2) in presence of hydrochloric acid at 80°C. The effect of various operation parameters, such as solution pH, initial metal ion concentration, contact time, and temperature, on the adsorption capacity of calix[4]naphthalene for Pb2+ have been investigated.Result
Experimental results showed that the adsorption of Pb2+ ions increased with the increase in solution pH and temperature. Langmuir and Freundlich isotherms models were used to describe the adsorption behavior of Pb2+ by calix[4]naphthalene. Equilibrium data fitted well with the Langmuir isotherm model and the maximum adsorption capacity of calix[4]naphthalene for Pb2+ at 30°C was found to be 29.15 mg g?1. Kinetic studies indicated that the adsorption followed pseudo-second order model and the thermodynamic studies revealed that the adsorption process was spontaneous and endothermic in nature. The obtained results demonstrated that calix[4]naphthalene can be used as an effective adsorbent for Pb2+ ions removal from water. 相似文献15.
Introduction
This paper is in response to criticism of our article “The human sex odds at birth after the atmospheric atomic bomb tests, after Chernobyl, and in the vicinity of nuclear facilities” published in Environ Sci Pollut Res 18(5):697–707, 2011.Methods
Our findings and methods concerning the disturbed human sex odds at birth have been criticized in this journal for being artifacts of data mining, that the concept of statistical significance was misunderstood, and that confounding factors have not been accounted for. Here, we show that this criticism has no basis. We applied well-established statistical methods to large official data sets, and confounding is less important at the level of secular sex odds trends in aggregated annual figures from countries or continents.Results and conclusions
Moreover, our results are strengthened by recent findings concerning increased infant death sex odds in Germany and increased Down syndrome prevalence at birth across Europe after Chernobyl. Prompted by our studies, an official investigation in Lower Saxony, Germany, by the “Niedersächsisches Landesgesundheitsamt (NLGA)” confirmed our observation of severely escalated sex odds within 40 km distance from the nuclear storage site in Gorleben, Germany.16.
Mukherjee AK Bordoloi NK 《Environmental science and pollution research international》2012,19(8):3380-3388
Purpose
The major aromatic constituents of petroleum products viz. benzene, toluene, and mixture of xylenes (BTX) are responsible for environmental pollution and inflict serious public concern. Therefore, BTX biodegradation potential of individual as well as formulated bacterial consortium was evaluated. This study highlighted the role of hydrogen peroxide (H2O2), nitrate, and phosphate in stimulating the biodegradation of BTX compounds under hypoxic condition.Materials and methods
The individual bacterium viz. Bacillus subtilis DM-04 and Pseudomonas aeruginosa M and NM strains and a consortium comprising of the above bacteria were inoculated to BTX-containing liquid medium and in soil. The bioremediation experiment was carried out for 120?h in BTX-containing liquid culture and for 90?days in BTX-contaminated soil. The kinetics of BTX degradation either in presence or absence of H2O2, nitrate, and phosphate was analyzed using biochemical and gas chromatographic (GC) technique.Results
Bacterial consortium was found to be superior in degrading BTX either in soil or in liquid medium as compared to degradation of same compounds by individual strains of the consortium. The rate of BTX biodegradation was further enhanced when the liquid medium/soil was exogenously supplemented with 0.01?% (v/v) H2O2, phosphate, and nitrate. The GC analysis of BTX biodegradation (90?days post-inoculation) in soil by bacterial consortium confirmed the preferential degradation of benzene compared to m-xylene and toluene.Conclusions
It may be concluded that the bacterial consortium in the present study can degrade BTX compounds at a significantly higher rate as compared to the degradation of the same compounds by individual members of the consortium. Further, addition of H2O2 in the culture medium as an additional source of oxygen, and nitrate and phosphate as an alternative electron acceptor and macronutrient, respectively, significantly enhanced the rate of BTX biodegradation under oxygen-limited condition. 相似文献17.
Background
Earthworm heavy metal concentrations (critical body residues, CBRs) may be the most relevant measures of heavy metal bioavailability in soils and may be linkable to toxic effects in order to better assess soil ecotoxicity. However, as earthworms possess physiological mechanisms to secrete and/or sequester absorbed metals as toxicologically inactive forms, total earthworm metal concentrations may not relate well with toxicity. 相似文献18.
Hédi Ben Mansour Yosra Ayed-Ajmi Ridha Mosrati David Corroler Kamel Ghedira Daniel Barillier Leila Chekir-Ghedira 《Environmental science and pollution research international》2010,17(7):1371-1378
Introduction
Acid violet 7 (AV7), mostly used in food, paper, cosmetic, and especially in textile industries, was degraded by Pseudomonas putida mt-2 at concentrations up to 200 mg/l. 相似文献19.
Stefan Trapp Michael Matthies Andreas Kaune 《Umweltwissenschaften und Schadstoff-Forschung》1994,6(1):31-40
Die Massenbilanz von PCDD/F—insbesondere von 2,3,7,8-TCDD—im System Boden-Pflanze-Luft wird mit einem einfachen konzeptuellen
Modell berechnet. Die wichtigsten Ergebnisse sind:
Hrsg.: Prof. Dr, Walter Kl?pffer, C.A.U. GmbH, Daimlerstra?e 23, D-63303 Dreieich Teil I: Modellierung des TransferverhaltensS. Trapp, M. Matthies, A. Kaune Teil II: Ausgasung aus dem Boden und PflanzenaufnahmeS. Trapp, M. Matthies Teil III: Transfefaktoren Bodne-Pflanze und Luft-PflanzeM. Matthies, S. Trapp 相似文献
1. | DerTransfer Boden/Wurzel findet für Feinwurzeln bis zu einem Gleichgewichtswert statt, der durch den Lipid- und Wassergehalt der Wurzel, die Sorption im Boden und den n-Oktanol/Wasser-Verteilungskoeffizienten bestimmt ist. Da der Transfer für gro?e Wurzelradii langsam abl?uft, ist der Gleichgewichtswert (der etwa gleiche Konzentrationen in Boden und Wurzel bedeutet) eine obere Grenze für die Aufnahme. |
2. | PCDD/F werden (zumindest für Gras und Getreide) nicht in nennenswerten Mengen mit dem Transpirationsstrom transportiert, so da? nur ein sehr geringerTransfer Boden/oberirdische Pflanzenteile innerhalb der Pflanze stattfindet. |
3. | Die Aufnahme von PCDD/F aus derLuft ins Blatt ist entscheidend für die Kontamination von oberirdischen Pflanzenteilen, wobei die Deposition sowohl von partikelgebundenen als auch von gasf?rmigen PCDD/F den Eintrag bestimmt. |
20.
Photocatalytic degradation of gaseous toluene by using immobilized titania/silica on aluminum sheets
Minoo Tasbihi Marko Kete Ashok M. Raichur Nata?a Novak Tu?ar Ur?ka Lavren?i? ?tangar 《Environmental science and pollution research international》2012,19(9):3735-3742