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Abdellatif Mellouki Armand Bianchi Alain Perichaud Georges Sauvet 《Marine pollution bulletin》1989,20(12):612-615
The most common way to prevent biofouling of immersed surfaces is to coat the exposed surfaces with a paint containing a biocide acting on marine organisms by diffusion into the surrounding water. However diffusion of toxins into the marine environment causes pollution and serious economic problems. This paper outlines the anti-microfouling properties of some insolubilized quaternary ammonium salts (grafted onto a vinyl copolymer by means of a covalent non-hydrolyzable bond). After immersion times in sea-water up to 4 months, the microbial cover was limited to bacterial forms, without microalgae or cyanobacteria as observed on the untreated, or tin-salt painted surfaces. Bacteria are mostly on unicell forms and numerous areas appear free of any microorganisms. As microbiofouling is an obligate step to macrofouling, this unleachable antifouling treatment could result in a prolonged protection. 相似文献
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The Arrhenius expressions and the data plotted in Figure 2 of Rodriguez et al. 2008 give rate coefficients of approximately 2?×?10-8 cm3 molecule-1 s-1 at 255 K. Such values are approximately two orders of magnitude larger than expected from simple collision theory (Finlayson-Pitts and Pitts 1986). The rate coefficients reported at sub-ambient temperatures are substantially greater than the gas kinetic limit and are not physically plausible. The rate coefficients reported by Rodriguez et al. imply a long range attraction between the reactants which is not reasonable for reaction of neutral species such as chlorine atoms and unsaturated alcohols. We also note that the pre-exponential A factors (10-23-10-20) and activation energies (?15 kcal mol-1) are not physically plausible. We conclude that there are large systematic errors in the study by Rodriguez et al. (Atmos Chem 59:187–197, 2008). 相似文献
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Mapping Buried Bedrock Topography with Gravity 总被引：3，自引：0，他引：3
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N. Tsalkani A. Mellouki G. Poulet G. Toupance G. Le Bras 《Journal of Atmospheric Chemistry》1988,7(4):409-419
The gas phase reactions of peroxyacetyl nitrate (PAN) with OH and Cl have been studied using the discharge-flow EPR method. The rate constants are found to be k
3=(7.5±1.4)×10-14 and k
4=(3.7±1.7)×10-13 cm3 molecule-1 s-1 at 298 K, respectively. These results confirm that the OH+PAN reaction will be the dominant sink of PAN in the middle and upper troposphere, whereas the reaction Cl+PAN will be negligible in contrast with previous estimations. 相似文献
5.
G. Solignac I. Magneron A. Mellouki A. Muñoz M. Martin Reviejo K. Wirtz 《Journal of Atmospheric Chemistry》2006,54(2):89-102
A study of the oxidation mechanism of N-methyl pyrrolidinone (C5H9NO, NMP) initiated by hydroxyl radicals was made at EUPHORE at atmospheric pressure (1000 ± 10) mbar of air and ambient temperature (T = 300 ± 5 K). The main products were N-methyl succinimide (NMS) (52 ± 4)% and N-formyl pyrrolidinone (FP) (23 ± 9)%. The relative rate technique was used to determine the rate constants of OH with NMP, NMS and FP, the measured values were (in units of cm3 molecule
− 1 s− 1): kNMP = (2.2 ± 0.4) × 10− 11, kNMS = (1.4 ± 0.3) × 10− 12 and kFP = (6 ± 1) × 10− 12. The results are presented and discussed in terms of the atmospheric impact. 相似文献
6.
Y. Katrib G. Deiber P. Mirabel S. Le Calvé C. George A. Mellouki G. Le Bras 《Journal of Atmospheric Chemistry》2002,43(3):151-174
A combined study of the OH gas phase reaction and uptake on aqueous surfacesof two carbonates, dimethyl and diethyl carbonate has been carried out todetermine the atmospheric lifetimes of these compounds. Rate coefficients havebeen measured for gas phase reactions of OH radicals with dimethyl and diethylcarbonate. The experiments were carried out using pulsed laser photolysis– laser induced fluorescence over the temperature range 263–372K and the kinetic data were used to derive the following Arrhenius expressions(in units of cm3 molecule–1 s–1):for dimethyl carbonate, k1 = (0.83±0.27)×10–12 exp [–(247± 98)/T] and fordiethyl carbonate, k2 = (0.46±0.15)×10–12 exp [(503± 203)/T]. At 298 K, therate coefficients obtained (in units of 10–12 cm3molecule–1 s–1) are: k1 =(0.35± 0.04) and k2 = (2.31± 0.29). The results arediscussed in terms of structure-activity relationships.The uptake coefficients of both carbonates on aqueous surfaces were measuredas a function of temperature and composition of the liquid phase, using thedroplet train technique coupled to a mass spectrometric detection. Dimethyland diethyl carbonate show very similar results. For both carbonates, themeasured uptake kinetics were found to be independent of the aqueous phasecomposition (pure water, NaOH solutions) but dependent on gas-liquid contacttime which characterises a surface saturation effect. The uptake coefficientvalues show a slight negative temperature dependence for both carbonates.These values vary from 1.4×10–2 to0.6×10–2 in the temperature range of 265–279 Kfor dimethyl carbonate, from 2.4×10–2 to0.9×10–2 in the temperature range of 270–279 Kfor diethyl carbonate. From the kinetic data, the following Henry's lawconstants were derived between 279 and 265 K: dimethyl carbonate,H1 = 20–106 M atm–1; and diethyl carbonate,H2 = 30–98 M atm–1. The reported data showthat the OH reaction is the major atmospheric loss process of these twocarbonates with lifetimes of 33 and 5 days, respectively, while the wetdeposition is a negligible process. 相似文献
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S. Le Calvé A. Mellouki G. Le Bras J. Treacy J. Wenger H. Sidebottom 《Journal of Atmospheric Chemistry》2000,37(2):161-172
Rate coefficients have been measured for the gas phasereactions of hydroxyl (OH) radicals and ozone with twounsaturated esters, allyl acetate(CH3C(O)OCH2CH=CH2) and isopropenylacetate (CH3C(O)OC(CH3)=CH2). The OHexperiments were carried out using the pulsed laserphotolysis – laser induced fluorescence technique overthe temperature range 243–372 K and the kinetic dataused to derive the following Arrhenius expressions (inunits of cm3 molecule-1 s-1): allylacetate, k
1 = (2.33 ± 0.27) ×10-12 exp[(732 ± 34)/T]; and isopropenyl acetate,k
2 = (4.52 ± 0.62) × 10-12exp[(809 ± 39)/T]. At 298 K, the rate coefficients obtained (inunits of 10-12 cm3 molecule-1 s-1)are: k
1 = (27.1 ± 3.0) and k
2= (69.6± 9.4). The relative rate technique has been usedto determine rate coefficients for the reaction ofozone with the acetates. Using methyl vinyl ketone asthe reference compound and a value of4.8 × 10-18 cm3 molecule-1s-1 asthe rate coefficient for its reaction with O3,the following rate coefficients were derived at 298 ± 4 K (in units of10-18 cm3molecule-1 s-1): allyl acetate, (2.4 ± 0.7) andisopropenyl acetate (0.7 ± 0.2). Theresults are discussed in terms of structure-activityrelationships and used to derive atmospheric lifetimesfor the acetates. 相似文献
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