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1.
?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2.
3.
Books
The age of the molecule 相似文献4.
Acknowledgment
Reviewer Acknowledgments 相似文献5.
Beitragsserien 2008
Ausblick 相似文献6.
《Umweltwissenschaften und Schadstoff-Forschung》2000,12(1):A4
Call for Papers
Phytoremediation organischer Schadstoffe 相似文献7.
Editorial
Editorial: Beitragsserie Meeresforschung 相似文献8.
Introduction
Titanium dioxide (TiO2) nanoparticle powders have been extensively studied to quickly photodegrade some organic pollutants; however, the effect of the particle size of TiO2 nanoparticle aggregates on degradation remains unclear because microscale aggregates form once the nanoparticle powders enter into water.Methods
The degradation of azo dye by different particle sizes of TiO2 nanoparticle aggregates controlled by NaCl concentrations was investigated to evaluate the particle size effect. Removal reactions of reactive black 5 (RB5) with TiO2 nanoparticles followed pseudo-first-order kinetics.Results
The increase of TiO2 dosage from 40 to 70?mg/L enhanced the degradation. At doses around 100?mg/L TiO2, degradation rates decreased which could be the result of poor UV light transmittance at high-particle concentrations. At average particle sizes of TiO2 nanopowders less than around 500?nm, the degradation rates increased with decreasing particle size. As the average particle size exceeded 500?nm, the degradation rates were not significantly changed.Conclusions
For the complete degradation experiments, the mineralization rates of total organic carbon disappearance are generally following the RB5 decolorization kinetic trend. These findings can facilitate the application of TiO2 nanoparticles to the design of photodegradation treatments for wastewater. 相似文献9.
10.
Reduzierte Autoemissionen — Neue Konzepte
Ankündigung einer neuen Beitragsserie in UWSF 相似文献11.
Maria-Veronica Sofianou Christos Trapalis Vassils Psycharis Nikos Boukos Tiverios Vaimakis Jiaguo Yu Wenguang Wang 《Environmental science and pollution research international》2012,19(9):3719-3726
Introduction
TiO2 anatase nanoplates and hollow microspheres were fabricated by a solvothermal?Chydrothermal method using titanium isopropoxide as a titanium precursor and hydrofluoric acid as a capping agent in order to enhance the formation of the {001} crystal facets of the anatase nanocrystals.Methods
These different morphological structures of TiO2 anatase can be achieved by only changing the solvent, keeping the amount of the precursor and of the capping agent identical during the solvothermal?Chydrothermal process.Results and discussion
After calcination of the samples, the adsorbed fluoride atoms on the {001} crystal facets of the TiO2 anatase nanocrystals were completely removed from their surface according to XPS analysis. The calcined TiO2 anatase structures were higher crystallized and the specific surface area of the catalysts increased, enhancing their photocatalytic activity in comparison to the non-calcined TiO2 anatase structures. All TiO2 anatase samples with adsorbed as well as non-adsorbed fluoride atoms on their {001} crystal facets, exhibited a higher photonic efficiency than Degussa P25, which was used as a reference.Conclusion
The fluoride free TiO2 anatase nanoplates exhibited the best photocatalytic activity in oxidizing the NO gas to NO2 and NO3 ?. 相似文献12.
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13.
《Umweltwissenschaften und Schadstoff-Forschung》2010,22(4):267-494
Jahrestagung
4. Gemeinsame Jahrestagung der GDCh-Fachgruppe Umweltchemie und ?kotoxikologie und der SETAC GLB 相似文献14.
Walter Kl?pffer Almut Beate Heinrich 《Umweltwissenschaften und Schadstoff-Forschung》2006,18(2):71-77
Preface
The age of E-mail Submission has passed — The Age of ESS Submission has arrived 相似文献15.
Tagungsakündigungen
Rückst?nde und Kontaminanten in Lebensmitteln 29. und 30. Oktober 2002, Atrium Hotel, Mainz 相似文献16.
Purpose
Lack of focus on the treatment of wastewaters bearing potentially hazardous pollutants like 1,1,2 trichloroethane and 1,1,2,2 tetrachloroethane in anaerobic reactors has provided an impetus to undertake this study. The objective of this exercise was to quantify the behavior of upflow anaerobic sludge blanket reactors and predict their performance based on the overall organic substrate removal.Methods
The reactors (wastewater-bearing TCA (R2), and wastewater-bearing TeCA (R3)) were operated at different hydraulic retention times (HRTs), i.e., 36, 30, 24, 18, and 12?h corresponding to food-to-mass ratios varying in the range of 0.2?C0.7?mg chemical oxygen demand (COD) mg?1 volatile suspended solids day?1. The process kinetics of substrate utilization was evaluated on the basis of experimental results, by applying three mathematical models namely first order, Grau second order, and Michaelis-Menten type kinetics.Results
The results showed that the lowering of HRT below 24?h resulted in reduced COD removal efficiencies and higher effluent pollutant concentrations in the reactors. The Grau second-order model was successfully applied to obtain the substrate utilization kinetics with high value of R 2 (>0.95). The Grau second-order substrate removal constant (K 2) was calculated as 1.12 and 7.53?day?1 for reactors R2 and R3, respectively.Conclusion
This study demonstrated the suitability of Grau second-order kinetic model over other models, for predicting the performance of reactors R2 and R3, in treating wastewaters containing chlorinated ethanes under different organic and hydraulic loading conditions. 相似文献17.
Liang B Yao Q Cheng H Gao S Kong F Cui D Guo Y Ren N Wang A 《Environmental science and pollution research international》2012,19(5):1385-1391
Purpose
With the aim of enhanced degradation of azo dye alizarin yellow R (AY) and further removal of the low-strength recalcitrant matter (LsRM) of the secondary effluent as much as possible, our research focused on the combination of aerobic bio-contact oxidation (ABO) with iron/carbon microelectrolysis (ICME) process.Materials and methods
The combined ABO (with effective volume of 2.4?l) and ICME (with effectively volume of 0.4?l) process were studied with relatively short hydraulic retention time (HRT) of 4 or 6?h.Results
At the HRT of 6?h with the reflux ratio of 1 and 2, the AY degradation efficiency in the final effluent was >96.5%, and the total organic carbon (TOC) removal efficiency were 69.86% and 79.44%, respectively. At the HRT of 4?h and the reflux ratio of 2, TOC removal efficiency and AY degradation efficiency were 73.94% and 94.89%, respectively. The ICME process obviously enhanced the total AY removal and the generated micromolecule acids and aldehydes then that wastewater backflow to the ABO where they were further biodegraded.Conclusion
The present research might provide the potential options for the advanced treatment azo dyes wastewater with short HRT and acceptable running costs. 相似文献18.
Müfit Bahadir 《Umweltwissenschaften und Schadstoff-Forschung》2006,18(2):134-137
GDCh-Rubrik: GDCh-FG Umweltchemie und ?kotoxikologie
Kooperationsvereinbarung GDCh-Fachgruppe Umweltchemie und ?kotoxikologie und UWSF — Z Umweltchem ?kotox 相似文献19.
Tsuji M Vogel CF Koriyama C Akiba S Katoh T Kawamoto T Matsumura F 《Chemosphere》2012,87(11):1228-1234
Background
One of the suggested health outcomes of PCB exposure is childhood asthma.Objectives
This study was conducted to find health relevant biomarkers providing the molecular epidemiological evidence for the positive relationship between exposure to PCBs and childhood asthma.Methods
Blood samples from fifteen asthmatic children as well as an equal number of non-asthmatic children (average 2 year old) were collected, and were analyzed for PCBs and their select marker expression by using qRT-PCR.Results
Among biomarkers examined IL-8 expression was significantly correlated to serum levels of PCB #163 + 164 (P = 0.022), #170 (P = 0.046), #177 (P = 0.022), #178 (P = 0.022) and #180 + 193 (P = 0.046) in a dose-dependent manner, which was found only among asthmatic children. In contrast, COX-2 correlations to individual congener levels were recognized only among control subjects, not among asthmatic subjects.Conclusion
Serum concentrations of PCB#163 + 164, #170, #177, #178 and #180 + 193 correlate significantly with IL-8 mRNA expressions among asthmatic children. 相似文献20.