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O3 Treatment (o3 + treatment)
Selected AbstractsEnhanced Treatment of Trace Pollutants by a Novel Electrolytic Cell,ENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 6 2006Y. Sakakibara Abstract Continuous experiments were conducted to evaluate the electrolytic performance of a novel 3-dimensional electrolytic cell consisting of granular Pt/Ti electrodes. The electric current efficiency to decompose indigotrisulfonate was approx. 96,%, while energy consumption was one to two orders of magnitude smaller than that for O3 treatment. Furthermore, the cell was successfully applied to treat trace endocrine disrupting chemicals (EDCs) and chlorinated compounds. Energy consumption was in the range of 2 to 10 Wh/m3. From these results, it was concluded that the present electrolytic cell would be a feasible alternative to conventional oxidation processes in water treatment. [source] Do elevated atmospheric CO2 and O3 affect food quality and performance of folivorous insects on silver birch?GLOBAL CHANGE BIOLOGY, Issue 3 2010PETRI A. PELTONEN Abstract The individual and combined effects of elevated CO2 and O3 on the foliar chemistry of silver birch (Betula pendula Roth) and on the performance of five potential birch-defoliating insect herbivore species (two geometrid moths, one lymantrid moth and two weevils) were examined. Elevated CO2 decreased the water concentration in both short- and long-shoot leaves, but the effect of CO2 on the concentration of nitrogen and individual phenolic compounds was mediated by O3 treatment, tree genotype and leaf type. Elevated O3 increased the total carbon concentration only in short-shoot leaves. Bioassays showed that elevated CO2 increased the food consumption rate of juvenile Epirrita autumnata and Rheumaptera hastata larvae fed with short- and long-shoot leaves in spring and mid-summer, respectively, but had no effect on the growth of larvae. The contribution of leaf quality variables to the observed CO2 effects indicate that insect compensatory consumption may be related to leaf age. Elevated CO2 increased the food preference of only two tested species: Phyllobius argentatus (CO2 alone) and R. hastata (CO2 combined with O3). The observed stimulus was dependent on tree genotype and the measured leaf quality variables explained only a portion of the stimulus. Elevated O3 decreased the growth of flush-feeding young E. autumnata larvae, irrespective of CO2 concentration, apparently via reductions in general food quality. Therefore, the increasing tropospheric O3 concentration could pose a health risk for juvenile early-season birch folivores in future. In conclusion, the effects of elevated O3 were found to be detrimental to the performance of early-season insect herbivores in birch whereas elevated CO2 had only minor effects on insect performance despite changes in food quality related foliar chemistry. [source] Effects of ozone exposure on the structural, mechanical and barrier properties of select plastic packaging filmsPACKAGING TECHNOLOGY AND SCIENCE, Issue 6 2002Banu F. Ozen Abstract The effects of ozone (O3) gas exposure at various concentrations and treatment times on structural, mechanical and barrier properties of polyethylene and polyamide films were investigated. Changes in the structure of the films were monitored using an FT-IR spectrometer. The results showed that O3 treatment affected polyethylene and polyamide films differently. While O3 treatment caused formation of oxygen-containing functional groups and degradation of polymeric chains in polyethylene films, O3 treatment of polyamide films significantly increased the ,C,N, stretch observed at 1125,cm,1 in the FT-IR spectra. The changes in the mechanical properties of polyethylene films depended on the O3 treatment conditions (temperature and O3 concentration were the most significant), but an increase in tensile strength of polyamide films was observed regardless of the treatment conditions. Permeability to O2 for both types of films decreased with increasing O3 treatment time. Copyright © 2003 John Wiley & Sons, Ltd. [source] Evidence that Branch Cuvettes are Reasonable Surrogates for Estimating O3 Effects in Entire Tree CrownsPLANT BIOLOGY, Issue 2 2007C. Then& Abstract: Within the scope of quantifying ozone (O3) effects on forest tree crowns it is still an open question whether cuvette branches of adult trees are reasonable surrogates for O3 responses of entire tree crowns and whether twigs exhibit autonomy in defense metabolism in addition to carbon autonomy. Therefore, cuvette-enclosed branches of mature beech (Fagus sylvatica) trees were compared with branches exposed to the same and different ozone regimes by a free-air fumigation system under natural stand conditions by means of a vice versa experiment. For this purpose, cuvettes receiving 1 × O3 air were mounted in trees exposed to 2 × O3 and cuvettes receiving 2 × O3 air were mounted in trees exposed to 1 × O3 in the upper sun crown. At the end of the fumigation period in September 2004, leaves were examined for differences in gas exchange parameters, pigments, antioxidants, carbohydrates, and stable isotope ratios. No significant differences in foliar gas exchange, total carbohydrates, stable isotope ratios, pigment, and antioxidant contents were found as a consequence of cuvette enclosure (cuvette versus free-air branches) of the same O3 concentrations besides increase of glucose inside the cuvettes and reduction of the de-epoxidation state of the xanthophyll cycle pigments. No significant ozone effect was found for the investigated gas exchange and most biochemical parameters. The total and oxidized glutathione level of the leaves was increased by the 2 × O3 treatment in the cuvette and the free-air branches, but this effect was significant only for the free-air branches. From these results we conclude that cuvette branches are useful surrogates for examining the response of entire tree crowns to elevated O3 and that the defence metabolism of twigs seems to be at least partially autonomous. [source] | ||||||||||