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Sample records for alkylbenzene sulfonate las

  1. Photocatalytic treatment of linear alkylbenzene sulfonate (LAS) in water.

    Science.gov (United States)

    Mehrvar, Mehrab; Venhuis, Sarah Hatfield

    2005-01-01

    The photocatalytic degradation of aqueous linear alkylbenzene sulfonate (LAS) was studied. Two different photocatalysts, Degussa P25 TiO2 and Hombikat UV 100 TiO2, were used to degrade aqueous linear alkylbenzene sulfonate in slurry batch photoreactors. For a 100 mg/L LAS solution based on first-order rate constants, the optimum photocatalyst loading for Degussa P25 TiO2 was 4.0 g/L, while for Hombikat UV 100 TiO2 it was 2.0 g/L. The photoactivity of Degussa P25 TiO2 it was higher than that of Hombikat UV 100 TiO2 for the treatment of LAS. A mixture of both photocatalysts did not improve the LAS degradation rates in batch experiments. Combination of Degussa P25 TiO2 and 600 mg/L H2O2 along with irradiation with UV light at either 254 or 365 nm did not improve the LAS degradation rates over the photocatalytic or photolytic processes individually.

  2. Fate of linear alkylbenzene sulfonate (LAS) in activated sludge plants

    NARCIS (Netherlands)

    Temmink, B.G.; Klapwijk, A.

    2004-01-01

    Monitoring data were collected in a pilot-scale municipal activated sludge plant to assess the fate of the C12-homologue of linear alkyl benzene sulfonate (LAS-C12). The pilot-plant was operated at influent LAS-C12 concentrations between 2 and 12 mg/l and at sludge retention times of 10 and 27 days<

  3. Fate of linear alkylbenzene sulfonate (LAS) in activated sludge plants.

    Science.gov (United States)

    Temmink, H; Klapwijk, Bram

    2004-02-01

    Monitoring data were collected in a pilot-scale municipal activated sludge plant to assess the fate of the C12-homologue of linear alkyl benzene sulfonate (LAS-C12). The pilot-plant was operated at influent LAS-C12 concentrations between 2 and 12 mg l(-1) and at sludge retention times of 10 and 27 days. Effluent and waste sludge concentrations varied between 5 and 10 microg l(-1) and between 37 and 69 microg g(-1) VSS, respectively. In the sludge samples only 2-8% was present as dissolved LAS-C12, whereas the remaining 92-98% was found to be adsorbed to the sludge. In spite of this high degree of sorption, more than 99% of the LAS-C12 load was removed by biodegradation, showing that not only the soluble fraction but also the adsorbed fraction of LAS-C12 is readily available for biodegradation. Sorption and biodegradation of LAS-C12 were also investigated separately. Sorption was an extremely fast and reversible process and could be described by a linear isotherm with a partition coefficient of 3.2 l g(-1) volatile suspended solids. From the results of biodegradation kinetic tests it was concluded that primary biodegradation of LAS-C12 cannot be described by a (growth) Monod model, but a secondary utilisation model should be used instead. The apparent affinity of the sludge to biodegrade LAS-C12 increased when the sludge was loaded with higher influent concentrations of LAS-C12.

  4. Environmental behavior of linear alkylbenzene sulfonate (LAS) in aquatic ecosystem

    Science.gov (United States)

    Zhang, Yongyuan; Tan, Yuyun; Korte, F.

    1991-03-01

    LAS degradation rate in Donghu Lake water under aerobic was much faster than under anaerobic condition. The half life of LAS in aerobic and anaerobic environment was 3.2 days and 57 days, respectively. The degradation rate at 25 27°C was approximately 20 times higher than that at 1.5 3.5 °C. In a laboratory model aquatic ecosystem, two stages of bioconcentration in fish, daphnia and snail were observed. The first stage, on second day exposure, resulted from accumulation of intact LAS, and the second stage, on 16th day exposure, was due to metabolites. The bioconcentration factor (BCF) of LAS was extremely low in the muscle of hybrid carp (0.64), but rather high (2485) in the gall bladder.

  5. Anaerobic bioprocessing of sewage sludge, focusing on degradation of linear alkylbenzene sulfonates (LAS)

    Energy Technology Data Exchange (ETDEWEB)

    Angelidaki, I.; Toraeng, L.; Waul, C.M.; Schmidt, J.E.

    2003-07-01

    Anaerobic degradation of sludge amended with linear alkylbenzene sulfonates (LAS) was tested in one stage continuous stirred tank reactor (CSTR) and a two stages reactor system consisting by a CSTR as first step and upflow anaerobic sludge bed (UASB) reactor in the second step. Anaerobic removal of LAS was only observed at the second step but not at the first step. Removal of LAS in the UASB reactors was approx. 80% where half was due to absorption and the other half was apparently due to biological removal as shown from the LAS mass balance. At the end of the experiment the reactors were spiked with {sup 14}C-LAS which resulted in 5.6% {sup 14}CO{sub 2} in the produced gas. Total mass balance of the radioactivity was however not achieved. In batch experiments it was found that LAS at concentrations higher than 50 mg/l is inhibitory for the most microbial groups of the anaerobic process. Therefore, low initial LAS concentration is a prerequisite for successful LAS degradation. The results from the present study suggest that anaerobic degradation of LAS is possible in UASB reactors when the concentration of LAS is low enough to avoid inhibition of microorganisms active in the anaerobic process. (author)

  6. Physicochemical determinants of linear alkylbenzene sulfonate (LAS) disposition in skin exposed to aqueous cutting fluid mixtures.

    Science.gov (United States)

    Baynes, Ronald E; Brooks, James D; Barlow, Beth M; Riviere, Jim E

    2002-06-01

    Linear alkylbenzene sulfonate (LAS) is added to cutting fluid formulations to enhance the performance of metal machining operations, but this surfactant can cause contact dermatitis in workers involved in these operations. The purpose of this study was to determine how cutting fluid additives influence dermal disposition of 14C-LAS in mineral oil- or polyethylene glycol 200 (PEG)-based mixtures when topically applied to silastic membranes and porcine skin in an in vitro flow-through diffusion cell system. 14C-LAS mixtures were formulated with three commonly used cutting fluid additives; 0 or 2% triazine (TRI), 0 or 5% triethanolamine (TEA), and 0 or 5% sulfurized ricinoleic acid (SRA). LAS absorption was limited to less than a 0.5% dose and the additives in various combinations influenced the physicochemical characteristics of the dosing mixture. LAS was more likely to partition into the stratum corneum (SC) in mineral oil mixtures, and LAS absorption was significantly greater in the complete mixture. TRI enhanced LAS transport, and the presence of SRA decreased LAS critical micelle concentration (CMC) which reduced LAS monomers available for transport. TEA increased mixture viscosity, and this may have negated the apparent enhancing properties of TRI in several mixtures. In summary, physicochemical interactions in these mixtures influenced availability of LAS for absorption and distribution in skin, and could ultimately influence toxicological responses in skin.

  7. Anaerobic biodegradation of linear alkylbenzene sulfonate (LAS) in upflow anaerobic sludge blanket (UASB) reactors.

    Science.gov (United States)

    Sanz, José L; Culubret, Elayne; de Ferrer, Juan; Moreno, Alfonso; Berna, José L

    2003-01-01

    The anaerobic biodegradation of Linear Alkylbenzene Sulfonate (LAS) was studied in Upflow Anaerobic Sludge Blanket Reactors (UASB). One reactor was fed with easily degradable substrates and commercial LAS solution during a period of 3 months (Reactor 1), meanwhile a second reactor was fed with a commercial LAS solution without co-substrate (Reactor 2) during 4 months. Both reactors were operated with an organic loading rate of 4-5 mg-LAS/l x day and a hydraulic retention time of one day. The LAS biodegradation was determined by full mass balance. LAS was analysed by HPLC in the liquid phase (influent and effluent streams of the reactors) as well as in the solid phase (granular sludge used as biomass). The results indicate a high level of removal (primary biodegradation: 64-85%). Biodegradation was higher in the absence of external co-substrates than in the presence of additional sources of carbon. This indicates that the surfactant can be partially used as carbon and energy source by anaerobic bacteria. Under the operating conditions used, inhibition of the methanogenic activity or any other negative effects on the biomass due to the presence of LAS were not observed. The methanogenic activity remained high and stable throughout the experiment.

  8. Methanogenic activity inhibition by increasing the linear alkylbenzene sulfonate (LAS) concentration.

    Science.gov (United States)

    Souza, Luiza F C; Florencio, Lourdinha; Gavazza, Savia; Kato, Mario T

    2016-07-02

    The effect of the initial concentration of linear alkylbenzene sulfonate (LAS) on specific methanogenic activity (SMA) was investigated in this work. Six anaerobic flasks reactors with 1 L of total volume were inoculated with anaerobic sludge (2 g VSS L(-1)). The reactors were assayed for 42 days, and fed with volatile fatty acids, nutrients, and LAS. The initial LAS concentrations were 0, 10, 30, 50, 75, and 100 mg L(-1) for the treatment flasks T1 (control), T2, T3, T4, T5, and T6, respectively. When compared with T1, T2 exhibited a 30% reduction in maximum SMA and total methane production (TMP). In treatment T3 through T6, the reductions were 44-97% (T3-T6) for SMA, and 30-90% (T3-T6) for TMP. Total LAS removal increased following the increase in the initial LAS concentration (from 36% at T1 to 76% at T6), primarily due to the high degree of sludge adsorption. LAS biodegradation also occurred (32% in all treatments), although this was most likely associated with the formation of non-methane intermediates. Greater removal by adsorption was observed in long-chain homologues, when compared to short-chain homologues (C13 > C10), whereas the opposite occurred for biodegradation (C10 > C13). The C13 homologue was adsorbed to a great extent (in mass) in T4, T5 and T6, and may also have inhibited methane formation in these treatments.

  9. Effect of additional carbon source on biodegradation of linear alkylbenzene sulfonate by las-utilizing bacteria

    Directory of Open Access Journals (Sweden)

    Kehinde I. Temitope Eniola

    2011-08-01

    Full Text Available Aerobic biodegradation of linear alkylbenzene sulfonate (LAS by LAS-utilizing bacteria (LUB in the presence of other sources of carbon (glucose and soluble starch was examined. Biodegradation of LAS was monitored as primary degradation in terms of half-life (t½ of the surfactant. Biodegradation of LAS by the individual LUB was slower in the presence of Glucose. Biodegradation of the surfactant by the various consortia of LUB was slower in the presence of the carbon sources: t½ increased to 3 days. The rates of biodegradation by the consortia can be ranked as: four-membered (t½=9 days > three-membered (t½=9 to 13 days > two-membered consortia (t½=10 to 15 days. Generally, degradation in the presence of the carbon sources was faster with the consortia than the individual species. Degradation of the surfactant by the LUB was generally fastest in the absence of additional carbon sources. The possible role of additional carbon sources in persistence of surfactant in water bodies and the application of the observation in management of LAS-containing-effluent is suggested.

  10. Evaluation of Linear Alkylbenzene Sulfonate (LAS) behaviour in agricultural soil through laboratory continuous studies.

    Science.gov (United States)

    Oliver-Rodríguez, B; Zafra-Gómez, A; Reis, M S; Duarte, B P M; Verge, C; de Ferrer, J A; Pérez-Pascual, M; Vílchez, J L

    2015-07-01

    The behaviour of Linear Alkylbenzene Sulfonate (LAS) in agricultural soil is investigated in the laboratory using continuous-flow soil column studies in order to simultaneously analyze the three main underlying phenomena (adsorption/desorption, degradation and transport). The continuous-flow soil column experiments generated the breakthrough curves for each LAS homologue, C10, C11, C12 and C13, and by adding them up, for total LAS, from which the relevant retention, degradation and transport parameters could be estimated, after proposing adequate models. Several transport equations were considered, including the degradation of the sorbate in solution and its retention by soil, under equilibrium and non-equilibrium conditions between the sorbent and the sorbate. In general, the results obtained for the estimates of those parameters that were common to the various models studied (such as the isotherm slope, first order degradation rate coefficient and the hydrodynamic dispersion coefficient) were rather consistent, meaning that mass transfer limitations are not playing a major role in the experiments. These three parameters increase with the length of the LAS homologue chain. The study will provide the underlying conceptual framework and fundamental parameters to understand, simulate and predict the environmental behaviour of LAS compounds in agricultural soils.

  11. Biotransformation of linear alkylbenzene sulfonate (LAS) by Phanerochaete chrysosporium: oxidation of alkyl side-chain.

    Science.gov (United States)

    Yadav, J S; Lawrence, D L; Nuck, B A; Federle, T W; Reddy, C A

    2001-01-01

    The white rot fungus Phanerochaete chrysosporium, which generally mineralizes substituted aromatics to CO2, transformed linear alkylbenzene sulfonate (LAS) surfactants mainly at their alkyl side chain. Degradation of LAS was evidenced by a zone of clearing on LAS-containing agar plates and colorimetric analysis of liquid cultures. Disappearance of LAS was virtually complete within 10 days in low nitrogen (2.4 mM N), high nitrogen (24 mM N) and malt extract (ME) liquid media. After 5 days of incubation in ME medium, transformation of LAS was complete at concentrations < or = 4 mg l(-1), but decreased at higher concentrations. The LAS degradation was not dependent on lignin peroxidases (LiPs) and manganese-dependent peroxidases (MnPs). Mineralization of 14C-ring-LAS to 14CO2 by P. chrysosporium was < 1% regardless of the culture conditions used. Thin layer chromatography and mass spectral analyses indicated that P. chrysosporium transformed LAS to sulfophenyl carboxylates (SPCs) through oxidative shortening of the alkyl side-chains. While LAS disappearance in the cultures was not dependent on LiPs and MnPs, transformation of the parent LAS moieties to SPCs was more extensive in low N medium that favors expression of these enzymes. The SPCs produced in LN cultures were shorter in chain- length than those produced in ME cultures. Also there was a notable shift in the relative abundance of odd and even chain length metabolites compared to the starting LAS particularly in the low N cultures suggesting the possible involvement of processes other than or in addition to beta-oxidation in the chain-shortening process.

  12. Effect of linear alkylbenzene sulfonate (LAS) on human intestinal Caco-2 cells at non cytotoxic concentrations.

    Science.gov (United States)

    Bradai, Mohamed; Han, Junkyu; Omri, Abdelfatteh El; Funamizu, Naoyuki; Sayadi, Sami; Isoda, Hiroko

    2016-08-01

    Linear alkylbenzene sulfonate (LAS) is a cytotoxic synthetic anionic surfactant widely present in the environment due to its large-scale production and intensive use in the detergency field. In this study, we investigated the effect of LAS (CAS No. 25155-30-0) at non cytotoxic concentrations on human intestinal Caco-2 cells using different in vitro bioassays. As results, LAS increased Caco-2 cell proliferation at concentrations ranging from 1 to 15 ppm, more significantly for shorter exposure time (24 h), confirmed using flow cytometry and trypan blue exclusion methods. Moreover, proteomics analysis revealed that this effect was associated with an over-expression of elongation factor 2 and dipeptidyl peptidase 3, and a down-regulation of 14-3-3 protein theta, confirmed at mRNA level using real-time PCR. These findings suggest that LAS at non cytotoxic concentrations, similar to those observed at wastewater treatment plants outlets, increases the growth rate of colon cancer cells, raising thereby its tumor promotion effect potential.

  13. Ecological Behavior of Linear Alkylbenzene Sulfonate (LAS) in Soil-Plant Systems

    Institute of Scientific and Technical Information of China (English)

    JIA Liang-Qing; OU Zi-Qing; OUYANG Zhi-Yun

    2005-01-01

    More and more linear alkylbenzene sulfonate (LAS) has contaminated the water and soil via pollution discharge,making it important to identify the ecological behavior and toxicity of LAS so as to carry out measures that will reduce its negative effects on the ecosystem. The ecological behavior of LAS, including degradation, migration, and plant uptake,in both soil-paddy rice and soil-soybean systems was studied. Reduction of LAS in pot and field plots followed the first order reaction kinetics with degradation half-lives of 35-50 days with LAS decreasing to very low concentrations after a season of crop growth. Strong migration ability for LAS was found and the breakthrough time in a 1.5 m soil monolith was significantly shortened to 23 days by preferential flow. Leachate volumes of soil-paddy and soil-soybean systems at preferential breakthrough were much different, while the leachate volumes at equilibrium governed by soil adsorption/desorption processes were very similar. Significant uptake of LAS in both paddy rice and soybeans was observed in pot and field experiments (P < 0.05). In aquatic culture, 20 μg mL-1 and above of LAS significantly inhibited the growth of paddy seedlings (P < 0.05). The critical concentration for LAS in soil inhibiting the growth and yield of paddy was 160 μg g-1; when higher, there was a strong negative influence, with decreases in height, spike length,and production; when lower than 80 μg g-1, paddy growth was stimulated. There was little effect of LAS on soybeans.

  14. Effects of linear alkylbenzene sulfonate (LAS) on the interspecific competition between Microcystis and Scenedesmus.

    Science.gov (United States)

    Zhu, Wei; Chen, Huaimin; Guo, Lili; Li, Ming

    2016-08-01

    The widespread use of detergents increases the concentration of surfactant in lakes and reservoirs. High surfactant loads produces toxicity to algae; however, the influence of the increasing surfactant on the competition between algae is not clear. In this paper, different amounts of linear alkylbenzene sulfonate (LAS) were added to test the effects of LAS on the competition between Microcystis aeruginosa and Scenedesmus obliquus under eutrophic condition. In single culture, the growth of S. obliquus was promoted under lower LAS concentrations (1 and 20 mg L(-1)), but cell density of S. obliquus reduced when treated with higher LAS concentration (100 mg L(-1)). The growth of M. aeruginosa was inhibited markedly with 20 and 100 mg L(-1) LAS. Compared with single culture, the result was opposite in co-cultures and the cell density of S. obliquus increased significantly when treated with LAS of 1, 20, and 100 mg L(-1). The specific growth rates of S. obliquus and M. aeruginosa in both cultures were 0.4-0.5 day(-1) and 0.6-0.7 day(-1), respectively, except that the specific growth rate of M. aeruginosa in both cultures treated with 100 mg L(-1) LAS was about 0.2 day(-1). M. aeruginosa dominated over S. obliquus in the co-culture without LAS, while the competition was completely opposite with the addition of 20 mg L(-1) LAS. The growth of S. obliquus treated with 20 mg L(-1) LAS was not affected significantly in single culture but was promoted by 75 % in co-culture. Moreover, the growth of S. obliquus in co-culture treated with 100 mg L(-1) LAS was promoted by more than 97 %. These results suggested that the increasing LAS would overturn the competition of algae in freshwater ecosystems.

  15. Photolytic treatment of aqueous linear alkylbenzene sulfonate.

    Science.gov (United States)

    Venhuis, Sarah Hatfield; Mehrvar, Mehrab

    2005-01-01

    Treatment of a model detergent compound, linear alkylbenzene sulfonate (LAS), using photolytic processes was studied. In the photolytic degradation of LAS, both ultraviolet (UV) light at 254 nm wavelength and its combination with hydrogen peroxide (H2O2) were investigated. Based on first-order rate constants, it was shown that 5000 mg/L of H2O2 for degradation of a 100-mg/L solution of linear alkylbenzene sulfonate was optimum. Addition of H2O2 at different illumination times with UV light at 254 nm did not improve first-order rate constants compared with the addition of H2O2 at the start of illumination. Degradation rates of the model compound (LAS) with three detergents were compared.

  16. Bioconcentration of the anionic surfactant linear alkylbenzene sulfonate (LAS) in the marine shrimp Palaemonetes varians: a radiotracer study.

    Science.gov (United States)

    Renaud, Florent; Warnau, Michel; Oberhänsli, François; Teyssié, Jean-Louis; Temara, Ali; Rouleau, Claude; Metian, Marc

    2014-08-15

    Uptake and depuration kinetics of dissolved [(14)C]C₁₂-6-linear alkylbenzene sulfonate (LAS) were determined in the shrimp Palaemonetes varians using environmentally relevant exposure concentration. The shrimp concentrated LAS from seawater with a mean BCF value of 120 L kg(-1) after a 7-day exposure. Uptake biokinetics were best described by a saturation model, with an estimated BCFss, of 159 ± 34 L kg(-1), reached after 11.5 days. Shrimp weight influenced significantly BCF value with smaller individuals presenting higher affinity to LAS. To the light of a whole body autoradiography, major accumulation of LAS occurred in the cephalothorax circulatory system (gills, heart, hepatopancreas) and ocular peduncle, but not in the flesh, limiting potential transfer to human consumers. LAS depuration rate constant value of the shrimp was 1.18 ± 0.08 d(-1) leading to less than 1% of remaining LAS in its tissues after 8 days of depuration.

  17. Treatment of linear alkylbenzene sulfonate (LAS) wastewater by internal electrolysis--biological contact oxidation process.

    Science.gov (United States)

    Cao, X Z; Li, Y M

    2011-01-01

    Surfactant wastewater is usually difficult to treat due to its toxicity and poor biodegradability. A separate physico-chemical or biochemical treatment method achieves a satisfactory effect with difficulty. In this study, treatment of the wastewater collected from a daily chemical plant by the combination processes of Fe/C internal electrolysis and biological contact oxidation was investigated. For the internal electrolysis process, the optimal conditions were: pH = 4-5, Fe/C = (10-15):1, air-water ratio = (10-20):1 and hydraulic retention time (HRT)= 2 h. For the biological contact oxidation process, the optimal conditions were: HRT = 12 h, DO = 4.0-5.0 mg/L. Treated by the above combined processes, the effluent could meet the I-grade criteria specified in Integrated Wastewater Discharge Standard of China (GB 8978-1996). The results provide valuable information for full-scale linear alkylbenzene sulfonate wastewater treatment.

  18. Linear alkylbenzene sulfonate (LAS) in water of Lake Dianchi--spatial and seasonal variation, and kinetics of biodegradation.

    Science.gov (United States)

    Wang, Zhi; Xiao, Bangding; Wu, Xingqiang; Tu, Xinhai; Wang, Yingcai; Sun, Xiaolei; Song, Lirong

    2010-12-01

    For the purpose of elucidating the environmental characteristics of anion surfactants [linear alkylbenzene sulfonates (LAS)] in the water of Lake Dianchi, a sampling investigation in the field from October 2006 to July 2007 and a batch of biodegradation experiments in the laboratory were carried out. The results showed that concentrations of LAS ranged from 18.6 to 260.1 μg L(-1), and the average concentration was 52.6 μg L(-1) in Lake Dianchi. The highest concentrations of LAS were found in the Northwest region, and the distribution of LAS varied through seasons, with much lower concentrations in fall than in any other seasons. LAS can be primarily biodegraded by microorganisms in the lake water, and the percentage of degradation was >97% after 28 days. Biodegradation of LAS was well-fitted with the kinetic model presented in this paper, and the half-lives ranged from 3.2 to 16.3 days. Temperature, pH, and initial concentrations could affect the biodegradation of LAS, among which temperature was the major factor influencing on biodegradation of LAS in water of Lake Dianchi.

  19. New sample treatment for determination of linear alkylbenzene sulfonate (LAS) in agricultural soils by liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Nimer, M; Ballesteros, O; Navalón, A; Crovetto, G; Verge, C; López, I; Berna, J L; Vílchez, J L

    2007-03-01

    A new sample-treatment procedure has been developed for determination of total linear alkylbenzene sulfonate (LAS), i.e. homologues and isomers, in agricultural soil. The procedure involves two steps, ultrasound-assisted extraction of LAS from the samples with methanol then clean-up of the methanolic extracts and preconcentration of the LAS by solid-phase extraction on two adsorbent cartridges (SAX and C18). The ultrasound-assisted procedure reduces extraction time (10 min in contrast with 6-12 h for conventional Soxhlet extraction) and requires only small volumes of organic solvent. The effect of different variables interacting in the ultrasound-assisted extraction process was studied. Finally, separation and quantification of the homologues and isomers of LAS was performed by liquid chromatography with fluorescence detection (LC-FD). 2-Octylbenzenesulfonic acid sodium salt (Na-2ØC8-LAS) was used as internal standard. The proposed method was satisfactorily used for determination of LAS in agricultural soil samples from the fertile plain of Granada (Spain).

  20. The degradation of linear alkylbenzene sulfonate (LAS) in the presence of light and natural biofilms: the important role of photosynthesis.

    Science.gov (United States)

    Hua, Xiuyi; Li, Ming; Su, Yulong; Dong, Deming; Guo, Zhiyong; Liang, Dapeng

    2012-08-30

    Photosynthesis of algae usually changes the chemical conditions of microenvironment in natural waters. However, few studies have been carried out to examine the effects of diurnal variation and photosynthesis on behavior of organic pollutants in aquatic environments. In this study, linear alkylbenzene sulfonate (LAS) was selected as a representative of non-persistent organic pollutants to investigate the degradation of this type of pollutants in the presence of light and natural biofilms by laboratory batch experiments, with special emphasis on the effect of photosynthesis of the biofilms. The maximum decrease of LAS was observed in the coexistence of both illumination and fully active biofilms, and about 75% of the LAS were removed after a 36-h degradation experiment. The removal of LAS was found to be dominated by photosynthesis of the biofilms, with lesser roles attributed to biodegradation and adsorption by the biofilms, and the role of direct photolysis was negligible. The production of some reactive oxygen species might account for the role of photosynthesis in decomposing the LAS. The study confirms the important roles of algae biofilms and their photosynthesis in determining the fate of organic pollutants in aquatic environments.

  1. Wide-range and accurate modeling of linear alkylbenzene sulfonate (LAS) adsorption/desorption on agricultural soil.

    Science.gov (United States)

    Oliver-Rodríguez, B; Zafra-Gómez, A; Reis, M S; Duarte, B P M; Verge, C; de Ferrer, J A; Pérez-Pascual, M; Vílchez, J L

    2015-11-01

    In this paper, rigorous data and adequate models about linear alkylbenzene sulfonate (LAS) adsorption/desorption on agricultural soil are presented, contributing with a substantial improvement over available adsorption works. The kinetics of the adsorption/desorption phenomenon and the adsorption/desorption equilibrium isotherms were determined through batch studies for total LAS amount and also for each homologue series: C10, C11, C12 and C13. The proposed multiple pseudo-first order kinetic model provides the best fit to the kinetic data, indicating the presence of two adsorption/desorption processes in the general phenomenon. Equilibrium adsorption and desorption data have been properly fitted by a model consisting of a Langmuir plus quadratic term, which provides a good integrated description of the experimental data over a wide range of concentrations. At low concentrations, the Langmuir term explains the adsorption of LAS on soil sites which are highly selective of the n-alkyl groups and cover a very small fraction of the soil surface area, whereas the quadratic term describes adsorption on the much larger part of the soil surface and on LAS retained at moderate to high concentrations. Since adsorption/desorption phenomenon plays a major role in the LAS behavior in soils, relevant conclusions can be drawn from the obtained results.

  2. [A new species of the genus Phenylobacterium for the degradation of LAS (linear alkylbenzene sulfonate)].

    Science.gov (United States)

    Ke, Na; Xiao, Changsong; Ying, Qifeng; Ji, Shulan

    2003-02-01

    A strain GZ6 that can biodegrade LAS (Linear Alkylbenzene Sulphonate) is identified. It is aerobic gram-negative rod or short-rod (0.5 to 0.8 by 1.0 to 2.0 Mm). It is mobile with a single polar flagellum. Optimum growth occurred at 30 degrees C and pH7.0. It is catalase positive, urease positive, and arginine decarboxylase positive. All the other physiological and biochemical tests performed were negative. It utilizes the xenobiotic compounds chloridazon, antipyrin and LAS as sole carbon sources. Most sugars, alcohols, and carboxylic acids are not utilized. It has Q-10 as the major quinone. The main cell fatty acids are Sum7, C16:0 and Sum4. The DNA G + C mol % content is 70.10. A phylogenic tree was constructed on the basis of 16S rDNA sequences. It showed that the previously known member of the genus Phenylobacterium, Phenylobacterium mobile DSM1986T, is the nearest neighbor to strain GZ6. The level of binary sequence similarity between them is 97.49%. And the DNA-DNA relatedness is 40%. These genetic analysis and their morphological difference show that they are different species of Phenylobacterium. A new species, Phenylobacterium mobile sp. nov., has been proposed.

  3. Anaerobic degradation of linear alkylbenzene sulfonate.

    Science.gov (United States)

    Mogensen, Anders S; Haagensen, Frank; Ahring, Birgitte K

    2003-04-01

    Linear alkylbenzene sulfonate (LAS) found in wastewater is removed in the wastewater treatment facilities by sorption and aerobic biodegradation. The anaerobic digestion of sewage sludge has not been shown to contribute to the removal. The concentration of LAS based on dry matter typically increases during anaerobic stabilization due to transformation of easily degradable organic matter. Hence, LAS is regarded as resistant to biodegradation under anaerobic conditions. We present data from a lab-scale semi-continuously stirred tank reactor (CSTR) spiked with linear dodecylbenzene sulfonate (C12 LAS), which show that C12 LAS was biodegradable under methanogenic conditions. Sorption of C12 LAS on sewage sludge was described with a Freundlich isotherm. The C12 LAS sorption was determined with different concentrations of total solids (TS). In the semi-continuously stirred tank reactor, 18% of the added C12 LAS was bioavailable and 20% was biotransformed when spiking with 100 mg/L of C12 LAS and a TS concentration of 14.2 mg/L. Enhanced bioavailability of C12 LAS was obtained in an upflow anaerobic sludge blanket (UASB) reactor inoculated with granular sludge and sewage sludge. Biodegradation under thermophilic conditions was 37% with LAS as sole carbon source. Benzaldehyde was produced in the UASB reactor during LAS transformation.

  4. Effects of pilot-plant photochemical pre-treatment (UV/H2O2) on the biodegradability of aqueous linear alkylbenzene sulfonate (LAS)

    OpenAIRE

    2005-01-01

    The effects of the photochemical pre-treatment by using a pilot-plant UV/H2O2 process on the biodegradability of aqueous linear alkylbenzene sulfonate (LAS) were studied. It was observed that the photochemical pre-treatment of the LAS solutions by UV-254/H2O2 increased the biodegradability of LAS solutions. Aqueous solutions with higher concentrations of LAS (> 100 mg/L) were non-biodegradable. The ratio of BOD5/COD of the pre-treated LAS solutions was increased, indicating that the ...

  5. Response of weeping willows to linear alkylbenzene sulfonate

    DEFF Research Database (Denmark)

    Yu, X.; Trapp, Stefan; Zhou, P.

    2006-01-01

    Linear alkylbenzene sulfonate (LAS) is the most commonly used anionic surfactant in laundry detergents and cleaning agents. LAS compounds are found in surface waters and soils. The short-term acute toxicity of LAS to weeping willows (Salix babylonica L.) was investigated. Willow cuttings were grown...... effects of LAS on willow trees are not expected for normal environmental conditions. (c) 2005 Elsevier Ltd. All rights reserved....

  6. Effect of linear alkylbenzene sulfonate (LAS) on ion transport and intracellular calcium in kidney distal epithelial cells (A6).

    Science.gov (United States)

    Bjerregaard, H F; Staermose, S; Vang, J

    2001-01-01

    Linear alkylbenzene sulfonate (LAS) is found in near-shore environments receiving wastewater from urban treatment plants in a concentration reported to have physiological and toxic effect on aquatic organisms. The aim of this study was to investigate the effect LAS on ion transport and homeostasis in epithelia cells. A6 cells form a polarised epithelium when grown on permeable supports, actively absorb sodium and secrete chloride. Only the addition of LAS (100 microM) to the apical solution of A6 epithelia resulted in an increase in the active ion transport measured as short circuit current (SCC) and transepithelial conductance (G(t)). This increase could not be affected by the sodium channel inhibitor amiloride (100 microM), indicating that LAS stimulated the chloride secretion. Change in the intracellular calcium concentration (Ca(2+))(i) was measured in fura-2 loaded A6 cells, since it known that increase in (Ca(2+))(i) stimulate chloride secretion. LAS induced a concentration-dependent increase in (Ca(2+))(i) from 5 to 200 microM, where the half-maximal stimulating concentration on 100 mM resulted in an increase in (Ca(2+))(i) from 108+/-15 to 570+/-26 nM (n=4; P<0.01). The increase in (Ca(2+))(i) could be blocked by the calcium chelator ethylenebis(5-oxyethylenenitrilo)tetraacetic acid (EGTA), showing that the effect of LAS was due to influx of extracellular calcium. Furthermore, it was shown that the calcium channel inhibitor verapamil (0.2 mM) abolished the LAS induced increase in (Ca(2+))(i) and Gt when applied to the apical solution. However, verapamil has no inhibitory effect on these parameters when the non-ionic detergent Triton X-100 (100 microM) was added to A6 cells. These results indicate that LAS induced a specific activation of calcium channels in the apical membrane of A6 epithelia, leading to increase in (Ca(2+))(i) and thereby increased chloride secretion as a result of stimulation of calcium-dependent chloride channels in the apical membrane

  7. Properties of polypyrrole doped with alkylbenzene sulfonates

    DEFF Research Database (Denmark)

    Bay, Lasse; Skaarup, Steen; West, Keld;

    2001-01-01

    -standing 10 mu m thick film is prepared electrochemically at a constant current from an aqueous solution of pyrrole and sodium alkylbenzene sulfonate. The mechanical properties of the film (tensile strength and Young's modulus) and the reversible linear elongation between the oxidised and reduced states...... are measured. Alkylbenzene sulfonates with alkyl chain lengths between 1 and 22 carbon atoms are used as dopant anion. The films made with the different anions have highly different properties and are here compared to outline the influence of the size of the anion. A maximum in linear elongation is found for p...

  8. Anaerobic degradation of linear alkylbenzene sulfonate in fluidized bed reactor

    OpenAIRE

    2010-01-01

    An anaerobic fluidized bed reactor was used to assess the degradation of the surfactant linear alkylbenzene sulfonate (LAS). The reactor was inoculated with sludge from an UASB reactor treating swine wastewater and was fed with a synthetic substrate supplemented with LAS. Sand was used as support material for biomass immobilization. The reactor was kept in a controlled temperature chamber (30±1 ºC) and operated with a hydraulic retention time (HRT) of 18 h. The LAS concentration was gradually...

  9. Optimization of linear alkylbenzene sulfonate (LAS) degradation in UASB reactors by varying bioavailability of LAS, hydraulic retention time and specific organic load rate.

    Science.gov (United States)

    Okada, Dagoberto Y; Delforno, Tiago P; Esteves, Andressa S; Sakamoto, Isabel K; Duarte, Iolanda C S; Varesche, Maria B A

    2013-01-01

    Degradation of linear alkylbenzene sulfonate (LAS) in UASB reactors was optimized by varying the bioavailability of LAS based on the concentration of biomass in the system (1.3-16 g TS/L), the hydraulic retention time (HRT), which was operated at 6, 35 or 80 h, and the concentration of co-substrates as specific organic loading rates (SOLR) ranging from 0.03-0.18 g COD/g TVS.d. The highest degradation rate of LAS (76%) was related to the lowest SOLR (0.03 g COD/g TVS.d). Variation of the HRT between 6 and 80 h resulted in degradation rates of LAS ranging from 18% to 55%. Variation in the bioavailability of LAS resulted in discrete changes in the degradation rates (ranging from 37-53%). According to the DGGE profiles, the archaeal communities exhibited greater changes than the bacterial communities, especially in biomass samples that were obtained from the phase separator. The parameters that exhibited more influence on LAS degradation were the SOLR followed by the HRT.

  10. Inhibition of the anaerobic digestion process by linear alkylbenzene sulfonates

    DEFF Research Database (Denmark)

    Gavala, Hariklia N.; Ahring, Birgitte Kiær

    2002-01-01

    Linear Alkylbenzene Sulfonates (LAS) are the most widely used synthetic anionic surfactants. They are anthropogenic, toxic compounds and are found in the primary sludge generated in municipal wastewater treatment plants. Primary sludge is usually stabilized anaerobically and therefore...... of the anaerobic digestion process should be seriously taken into consideration when wastewater from a surfactant producing industry is to be treated biologically or enter a municipal wastewater treatment plant that employs anaerobic technology. The upper allowable biomass specific LAS concentration should be 14...

  11. Effect of temperature and organic nutrients on the biodegradation of linear alkylbenzene sulfonate (LAS) during the composting of anaerobically digested sludge from a wastewater treatment plant.

    Science.gov (United States)

    Sanz, E; Prats, D; Rodríguez, M; Camacho, A

    2006-01-01

    Limits on the application of biosolids (anaerobically processed sludges from wastewater treatment plants) as fertilizers for the amendment of soil are becoming greater because of the accumulation of recalcitrant substances, making necessary the use of techniques that bring the concentration of xenobiotics to lower concentrations than those permitted. In general, the biosolids composting process is sufficient to reduce the usual concentration of linear alkylbenzene sulfonates (LAS) to low levels. In this work, an assessment is made on the effect of temperature in the capacity of enriched bacterial populations to biodegrade LAS, together with the influence that the available nutrients may have in the biodegradation of these compounds. The results show that the microbial metabolism of LAS was not observed in the thermophilic range. The optimum temperature for the biodegradation of LAS appears to be around 40 degrees C, this is, the lowest assayed here, and at this temperature the differences in the biodegradation of LAS among the nutritionally supplemented cultures are small.

  12. Elimination of Linear Alkylbenzene Sulfonate (LAS) and soap during composting of anaerobic sludge

    Energy Technology Data Exchange (ETDEWEB)

    Prats, D.; Rodriguez, M.; Muela, M.A.; Llamas, J.M.; Moreno, A.; Ferrer, J. De; Berna, J.L.

    2003-07-01

    The composting plant uses a variety of agricultural residue and sludge from nearby wastewater treatment plants. The results obtained indicate a very high removal of LAS (>97%) in a very short period of time while the removal of soap was substantially lower (32%) as well as the elimination of TOC (total organic matter). The average half life of LAS in the process was between 6 and 9 days which is very short compared to the average residence time of the feed in the composting process (40 days). (author)

  13. Probabilistic risk assessment for linear alkylbenzene sulfonate (LAS) in sewage sludge used on agricultural soil.

    Science.gov (United States)

    Schowanek, Diederik; David, Helen; Francaviglia, Rosa; Hall, Jeremy; Kirchmann, Holger; Krogh, Paul Henning; Schraepen, Nathalie; Smith, Stephen; Wildemann, Tanja

    2007-12-01

    Deterministic and probabilistic risk assessments were developed for commercial LAS in agricultural soil amended with sewage sludge. The procedure done according to ILSI Europe's Conceptual Framework [Schowanek, D., Carr, R., David, H., Douben, P., Hall, J., Kirchmann, H., Patria, L., Sequi, P., Smith, S., Webb, S.F., 2004. A risk-based methodology for deriving quality standards for organic contaminants in sewage sludge for use in agriculture-conceptual Framework. Regul. Toxicol. Pharmacol. 40 (3), 227-251], consists of three main steps. First, the most sensitive endpoint was determined. This was found to be the chronic ecotoxicity of LAS to soil invertebrates and plants. Additional endpoints, such as potential for plant uptake and transfer in the food chain, leaching to groundwater, surface erosion run-off, human health risk via drinking water, plant consumption and soil ingestion were also systematically evaluated but were all assessed to be of little toxicological significance. In the second step, a back-calculation was conducted from the Predicted No-Effect Concentration in soil (PNECsoil) to a safe level of LAS in sludge (here called 'Sludge Quality Standard'; SQS). The deterministic approach followed the default agricultural soil exposure scenario in the EU-Technical Guidance Document (TGD). The SQS for LAS was calculated as 49 g/kg sludge Dry Matter (DM). In order to assess the potential variability as a result of varying agricultural practices and local environmental conditions, two probabilistic exposure assessment scenarios were also developed. The mean SQS was estimated at 55 and 27.5 g/kg DM for the homogeneous soil mixing and soil injection scenarios, respectively. In the final step, the resulting SQS values were evaluated for consistency and relevance versus available information from agricultural experience and field tests. No build-up, adverse impact on soil fertility, agronomic performance, or animal/human health have been reported for agricultural

  14. Effect of linear alkylbenzene sulfonate (LAS) and atrazine on marine microalgae.

    Science.gov (United States)

    Debelius, B; Forja, J M; Del Valls, A; Lubián, L M

    2008-01-01

    Five marine microalgae (Tetraselmis chuii, Rhodomonas salina, Chaetoceros sp., Isochrysis galbana (T-iso) and Nannochloropsis gaditana), in the same biovolume quantity, were exposed to 72h growth-inhibition tests with atrazine and LAS. In all cases, the inhibition effect of atrazine was higher than that of LAS up to two orders of magnitude higher in the case of T. chuii. In a second part of the study, initial cellular densities for each microalga strain and fixed organic compound concentration were varied, and results show density has a clear influence in growth inhibition tests. Finally, the sum of all data obtained in the study was expressed in terms of "toxic cellular quota" (mass of chemical substance per cell). The result was a sigmoid curve with a good fit, including the two main factors in toxicity tests, initial cellular density and contaminant concentration. This toxic cellular quota exhibits a general tendency to increase with cell volume/size.

  15. Marine microalgae toxicity test for linear alkylbenzene sulfonate (LAS) and alkylphenol ethoxylate (APEO).

    Science.gov (United States)

    Moreno-Garrido, I; Hampel, M; Lubián, L M; Blasco, J

    2001-10-01

    Different microalgal species have been used in growth-inhibition tests to determine the toxic concentrations of anionic and non-ionic surfactants to phytoplankton. The species used were selected from different taxonomic groups, all of considerable ecological relevance to marine environments. The toxicity of the C13 LAS homologue to the microalgal species selected was usually one order of magnitude greater than that of the C11 homologue. The toxicity of a commercial LAS mixture to different microalgal species was also checked. For this material and C. gracilis, cellular counting by means of a Neubauer chamber and by use of a flow cytometer were compared; differences between the two methods were insignificant. The toxicity of decaethoxylated nonylphenol non-ionic surfactant to C. gracilis was also checked; the EC50 value for this compound was 1.0 mg L(-1).

  16. Properties of polypyrrole doped with alkylbenzene sulfonates

    Science.gov (United States)

    Bay, Lasse; Skaarup, Steen; West, Keld; Mazur, Tanja; Joergensen, Ole; Rasmussen, Helle D.

    2001-07-01

    Conducting polymers such as polypyrrole (PPy) doped with large anionic detergents have high stability in aqueous systems. PPy can be reversibly oxidised and reduced electrochemically. The redox change of PPy is accompanied by a change in volume of the polymer. This is partly ascribed to take-up of ions and solvent molecules. This volume change can be used as a polymer actuator (artificial muscle) working in a narrow voltage range (less than 1 V). The properties of the PPy polymer are largely determined by the dopant ions and also by the deposition conditions and the substrate. A free-standing 10 micrometers thick film is prepared electrochemically at a constant current from an aqueous solution of pyrrole and sodium alkylbenzene sulfonate. The mechanical properties of the film (tensile strength and Young's modulus) and the reversible linear elongation between the oxidised and reduced states are measured. Alkylbenzene sulfonates with alkyl chain lengths between 1 and 22 carbon atoms are used as dopant anion. The films made with the different anions have highly different properties and are here compared to outline the influence of the size of the anion. A maximum in linear elongation is found for p-(n-octyl)benzene sulfonate and in conductivity for p-(n-butyl)benzene sulfonate.

  17. Efficiency of conventional activated sludge in the removal of linear alkylbenzene sulfonate from municipal sewage

    OpenAIRE

    2014-01-01

    Background: Linear Alkylbenzene Sulfonate (LAS) is an anionic detergent that is abundantly produced in different countries and discharged into natural environment through wastewater collection systems. Wastewater treatment systems play an important role in the removal of this contaminant. The purpose of this study was to determine the efficiency of a conventional activated sludge system in removing linear alkylbenzene sulfonate from wastewater in Kermanshah. Methods: This cross-sectional d...

  18. Anionic surfactant linear alkylbenzene sulfonates (LAS) in sediments from the Gulf of Gdańsk (southern Baltic Sea, Poland) and its environmental implications.

    Science.gov (United States)

    Hampel, Miriam; Mauffret, Aourell; Pazdro, Ksenia; Blasco, Julian

    2012-10-01

    Linear alkylbenzene sulfonate (LAS) is a group of anionic surfactants employed in the formulation of laundry and cleaning products, with a global production rate of 4 million metric tons. Sediments from the Polish coast of the southern Baltic Sea were collected at ten stations. Total LAS concentrations, measured by high-performance liquid chromatography, were between 0.04 and 0.72 mg LAS·kg(-1) dry weight. Highest LAS concentrations were found in suspended matter collected from the Vistula River, sediment collected close to the Vistula River mouth and from the Gdańsk Deep, known as the depositional area. With the obtained environmental LAS concentrations, a risk assessment for this surfactant has been carried out, based on publicly available acute and chronic toxicity data in target organisms. The results indicated that LAS could pose a low risk for the existing benthic community applying worst case scenario assessment. This is the first time that levels of LAS have been measured in environmental samples of the southern Baltic Sea.

  19. Anaerobic degradation of linear alkylbenzene sulfonate in fluidized bed reactor

    Directory of Open Access Journals (Sweden)

    L. L. Oliveira

    2010-12-01

    Full Text Available An anaerobic fluidized bed reactor was used to assess the degradation of the surfactant linear alkylbenzene sulfonate (LAS. The reactor was inoculated with sludge from an UASB reactor treating swine wastewater and was fed with a synthetic substrate supplemented with LAS. Sand was used as support material for biomass immobilization. The reactor was kept in a controlled temperature chamber (30±1 ºC and operated with a hydraulic retention time (HRT of 18 h. The LAS concentration was gradually increased from 8.2±1.3 to 45.8±5.4 mg.L-1. The COD removal was 91%, on average, when the influent COD was 645±49 mg.L-1. The results obtained by chromatographic analysis showed that the reactor removed 93% of the LAS after 270 days of operation.

  20. Primary biodegradation of linear alkyltoluene and alkylbenzene sulfonates.

    Science.gov (United States)

    Singh, M; Satish, S

    1989-01-01

    Studies on the primary biodegradation of linear dodecylbenzene sulfonate, linear dodecyltoluene sulfonate, linear C(10-14) benzene sulfonate, linear C(10-14) toluene sulfonate, commercial samples of linear C(10-14) benzene sulfonate and branched dodecylbenzene sulfonate (DDBS) were carried out using a microbial culture developed from garden soil. Results show that linear alkyl toluene (LAT) is as degradable as linear alkylbenzene (LAB) in 7 days. However, a slower rate of degradation was noted with LAT. Various distributions of the positional isomers of the phenyl ring in the alkane chain of C(10-14) LAB showed no change in the pattern of primary biodegradation.

  1. Anaerobic degradation of linear alkylbenzene sulfonate

    DEFF Research Database (Denmark)

    Mogensen, Anders Skibsted; Haagensen, Frank; Ahring, Birgitte Kiær

    2003-01-01

    increases during anaerobic stabilization due to transformation of easily degradable organic matter. Hence, LAS is regarded as resistant to biodegradation under anaerobic conditions. We present data from a lab-scale semi-continuously stirred tank reactor (CSTR) spiked with linear dodecylbenzene sulfonate (C...

  2. Response of weeping willows to linear alkylbenzene sulfonate.

    Science.gov (United States)

    Yu, Xiaozhang; Trapp, Stefan; Zhou, Puhua; Peng, Xiaoying; Cao, Xi

    2006-06-01

    Linear alkylbenzene sulfonate (LAS) is the most commonly used anionic surfactant in laundry detergents and cleaning agents. LAS compounds are found in surface waters and soils. The short-term acute toxicity of LAS to weeping willows (Salix babylonica L.) was investigated. Willow cuttings were grown in hydroponic solution spiked with LAS at 24.0+/-1 degrees C for 192 h. The normalized relative transpiration of plants was used to determine toxicity. Severe reduction of the transpiration was only found for high doses of LAS (240 mgl(-1)). Chlorophyll contents in leaves of treated plants varied with the dose of LAS, but there was no significant linear correlation. The activities of the enzymes superoxide dismutases (SOD), catalase (CAT), and peroxidase (POD) were quantified at the end of experiments. At higher concentrations of LAS (240 mgl(-1)), the activities of SOD and CAT were decreased. The correlation between the dose of LAS and the POD activity in leaf cells was the highest of all enzyme assays (R(2)=0.5). EC(50) values for a 50% inhibition of the transpiration of the trees were estimated to 374 mgl(-1) (72 h) and 166 mgl(-1) (192 h). Results from this experiment indicated that phytotoxic effects of LAS on willow trees are not expected for normal environmental conditions.

  3. Anaerobic degradation of linear alkylbenzene sulfonate (LAS) in fluidized bed reactor by microbial consortia in different support materials.

    Science.gov (United States)

    de Oliveira, Lorena Lima; Costa, Rachel Biancalana; Okada, Dagoberto Yukio; Vich, Daniele Vital; Duarte, Iolanda Cristina Silveira; Silva, Edson Luiz; Varesche, Maria Bernadete Amâncio

    2010-07-01

    Four anaerobic fluidized bed reactors filled with activated carbon (R1), expanded clay (R2), glass beads (R3) and sand (R4) were tested for anaerobic degradation of LAS. All reactors were inoculated with sludge from a UASB reactor treating swine wastewater and were fed with a synthetic substrate supplemented with approximately 20 mg l(-1) of LAS, on average. To 560 mg l(-1) COD influent, the maximum COD and LAS removal efficiencies were mean values of 97+/-2% and 99+/-2%, respectively, to all reactors demonstrating the potential applicability of this reactor configuration for treating LAS. The reactors were kept at 30 degrees C and operated with a hydraulic retention time (HRT) of 18h. The use of glass beads and sand appear attractive because they favor the development of biofilms capable of supporting LAS degradation. Subsequent 16S rRNA gene sequencing and phylogenetic analysis of samples from reactors R3 and R4 revealed that these reactors gave rise to broad microbial diversity, with microorganisms belonging to the phyla Bacteroidetes, Firmicutes, Actinobacteria and Proteobacteria, indicating the role of microbial consortia in degrading the surfactant LAS.

  4. Assessment of the potential toxicity of a linear alkylbenzene sulfonate (LAS) to freshwater animal life by means of cladoceran bioassays.

    Science.gov (United States)

    Coelho, Katiuscia da Silva; Rocha, Odete

    2010-04-01

    The acute and chronic toxic effects of LAS on the cladocerans Daphnia similis, Ceriodaphnia dubia and Ceriodaphnia silvestrii were tested. Both types of toxicity bioassays and the methods of culture and stock maintenance of the test organisms conformed to the recommendations of ABNT (Brazilian Society of Technical Standards), which closely follow the standard methods of USEPA. The results obtained for EC(50) (48 h) were: 14.17 mg L(-1) for D. similis, 11.84 mg L(-1) for C. dubia and 13.52 mg L(-1) for C. silvestrii. In the chronic toxicity tests performed on C. dubia and C. silvestrii, there was a significant decrease in the fecundity of the exposed animals; the value of NOEC for C. dubia and C. silvestrii were 1.00 mg L(-1) and 2.50 mg L(-1), respectively. Cladoceran bioassays provided evidence that LAS concentration as low as 1.00 mg L(-1) can damage invertebrate animal life in freshwaters, concentrations that can be found in many eutrophic rivers and reservoirs.

  5. Formation of metabolites during biodegradation of linear alkylbenzene sulfonate in an upflow anaerobic sludge bed reactor under thermophilic conditions

    DEFF Research Database (Denmark)

    Mogensen, Anders Skibsted; Ahring, Birgitte Kiær

    2002-01-01

    Biodegradation of linear alkylbenzene sulfonate (LAS) was shown in an upflow anaerobic sludge blanket reactor under thermophilic conditions. The reactor was inoculated with granular biomass and fed with a synthetic medium and 3 mumol/L of a mixture of LAS with alkylchain length of 10 to 13 carbon...

  6. TOXIC EFFECTS OF LINEAR ALKYLBENZENE SULFONATE, ANTHRACENE AND THEIR MIXTURE ON GROWTH OF A MICROBIAL CONSORTIUM ISOLATED FROM POLLUTED SEDIMENT

    OpenAIRE

    2010-01-01

    The aim of this study was to determine the effect of linear alkylbenzene sulfonate (LAS), anthracene and a LAS-anthracene mixture on the growth of a microbial consortium isolated from polluted sediment. The microbial consortium was grown in a sterile glass bottle with mineral medium containing 1 g/L of glucose. Microbial growth inhibition produced by LAS, anthracene and combinations of LAS and anthracene was determined by viable count in nutritive agar; inhibitory concentration 50 (IC50) was ...

  7. How adaptation and mass transfer control the biodegradation of linear alkylbenzene sulfonate by activated sludge.

    Science.gov (United States)

    Rittmann, B E; Tularak, P; Lee, K C; Federle, T W; Itrich, N R; Kaiser, S K; Shi, J; McAvoy, D C

    2001-01-01

    We use a nonsteady-state model to evaluate the effects of community adaptation and sorption kinetics on the fate of linear alkylbenzene sulfonate (LAS) in batch experiments conducted with activated sludge that was continuously fed different concentrations of LAS. We observed a sharp decrease in the biodegradation rate between 30 and 60 minutes and the presence of an LAS residual at the end of the batch experiments. The modeling analysis indicates that these phenomena were caused by relatively slow inter-phase mass transport of LAS. The modeling analyses also showed that the amount of LAS-degrading biomass increased when the continuous activated sludge was fed a higher LAS concentration. Although community adaptation to LAS involved accumulation of more LAS degraders, the increase was not proportional to the feed concentration of LAS, which supports the concept that LAS degraders also utilized portions of the general biochemical oxygen demand (BOD) fed to the continuous activated sludge systems.

  8. [Hygienic assessment of biologically rigid linear alkylbenzene sulfonates].

    Science.gov (United States)

    Bocharov, V V; Ryzhkova, O A

    2010-01-01

    It has been found that there are both biologically rigid and biologically soft homologues in the homologous series of linear alkylbenzene sulfonates (LABS). It is shown that absorption of LABS molecules from aqueous to activated sludge phase may serve as a determinant that should be used to refer a homologue to as rigid or soft surfactants. The biodegradability, detergency, and toxicity of LABS were ascertained to be related to the size of molecular alkyl molecular substitute. It has established that the fractional compositions of linear alkobenzenes should be changed for the synthesis of LABS that have the maximum detergency, a high biodegradability rate, and a low toxicity.

  9. Efficiency of conventional activated sludge in the removal of linear alkylbenzene sulfonate from municipal sewage

    Directory of Open Access Journals (Sweden)

    Razieh Khamutian

    2014-04-01

    Full Text Available Background: Linear Alkylbenzene Sulfonate (LAS is an anionic detergent that is abundantly produced in different countries and discharged into natural environment through wastewater collection systems. Wastewater treatment systems play an important role in the removal of this contaminant. The purpose of this study was to determine the efficiency of a conventional activated sludge system in removing linear alkylbenzene sulfonate from wastewater in Kermanshah. Methods: This cross-sectional descriptive study was conducted on the wastewater in Kermanshah for 10 months. In order to determine the efficiency of the influent activated sludge process, 60 wastewater samples were taken after primary sedimentation and effluent of wastewater treatment system and LAS concentration was measured. All the sampling and testing methods were performed according to the standard method guidelines. Results: The results showed the means of LAS removal in the winter and warm seasons were 90.8% and 96.5%, respectively. The total mean of LAS removal in this system was 93.9 ±3.6. In addition, COD and TSS removal levels in winter were 88.3% and 72.3%; these values, however, in the summer were 86.9%, and 83.3%, respectively. Conclusion: The results showed that the conventional activated sludge process plays a pivotal role in the removal of LAS concentration. Moreover, the effluent concentration of LAS is less than the environmental standards for discharge into surface water in warm seasons.

  10. Preparation of Overbased Calcium Alkylbenzene Sulfonate for Formulating Complex Sulfonate Grease

    Institute of Scientific and Technical Information of China (English)

    Liu Yinong

    2015-01-01

    Six kinds of alkylbenzene sulfonic acids were selected to prepare the sulfonates S1—S6. Among them, the sul-fonates S3, S4, and S6 could be incorporated into lubricating grease with good performance in comparison with the grease produced from commercial sulfonates T106-1 and T106-2. The optimized conditions for synthesis of the sulfonates S3, S4, and S6were explored by using different mass ratios of methanol, water and the type of copromoters. It was found out that the appropriate conditions for synthesis of the sulfonate S3 included a methanol to M (M is the total mass of alkylbenzene sulfonic acid and base oil) mass ratio of 16%, a water to M mass ratio of 4%, and a copromoter A to M mass ratio of 2%; the appropriate conditions for synthesis of the sulfonate S4 included a methanol to M mass ratio of 24%, a water to M mass ratio of 2%, a copromoter B to M mass ratio of 2%; and the optimized conditions for synthesis of the sulfonate S6 included a methanol/ M mass ratio of 8%, a water/M mass ratio of 4% and a copromoter B/M mass ratio of 2%. The new sulfonates S3, S4, and S6 produced under the optimized conditions exhibited higher TBN and better antiwear property in camparison with the previous products. Grease samples G9, G10, and G11 were prepared with new sulfonates S3, S4, and S6 successfully and exhibited improved water stability and high temperature performance.

  11. Biodegradation of linear alkylbenzene sulfonates and their degradation intermediates in seawater.

    Science.gov (United States)

    Leon, Víctor M; Gómez-Parra, Abelardo; González-Mazo, Eduardo

    2004-04-15

    A study has been made of the aerobic biodegradation of linear alkylbenzene sulfonates (C12 and C11 homologues) and sulfophenylcarboxylic acids (C5 and C11 homologues) in seawater at concentrations of the same order as those detected ones in coastal waters influenced by wastewater effluents, at different temperatures, and both with and without the addition of an inoculum adapted to the presence of linear alkylbenzene sulfonate (LAS). The biodegradation of C12LAS, C11LAS, C5SPC, and C11SPC exceeds 99% in all tests performed and can be satisfactorily fitted to a second-degree polynomial without an independent term. The kinetic of degradation of LAS presents a clear seasonal component, since the process is considerably inhibited at lower temperatures; it is also kinetically enhanced by the presence of the inoculum. The intermediates detected for all the cases are sulfophenylcarboxylic acids (SPCs), the most abundant being those intermediates produced by the omega- and beta-oxidations of the parent compound, although intermediates produced by the alpha-oxidation have also been detected. The kinetic of the SPCs generated can be described using a model composed of two terms that represent the formation and the degradation of these intermediates. The total disappearance of the SPCs in all cases indicates that the degradation of LAS in seawater at the tested concentrations in aerobic conditions is complete.

  12. Liquid Phase Micro-Extraction of Linear Alkylbenzene Sulfonate Anionic Surfactants in Aqueous Samples

    OpenAIRE

    2011-01-01

    Hollow fiber liquid phase micro-extraction (LPME) of linear alkylbenzene sulfonates (LAS) from aqueous samples was studied. Ion pair extraction of C10, C11, C12 and C13 homologues was facilitated with trihexylamine as ion-pairing agent, using di-n-hexylether as solvent for the supported liquid membrane (SLM). Effects of extraction time, acceptor buffer concentration, stirring speed, sample volume, NaCl and humic acids were studied. At 10–50 μg L−1 linear R2-coefficients were 0.99 for C10 and ...

  13. Combined photochemical and biological processes for the treatment of linear alkylbenzene sulfonate in water.

    Science.gov (United States)

    Mehrvar, Mehrab; Tabrizi, Gelareh Bankian

    2006-01-01

    In this study, the effects of photochemical pre-treatment (pilot-plant UV/H2O2 process) of linear alkylbenzene sulfonate (LAS) on its subsequent biological treatment were examined. It was observed that the photochemical pre-treatment of the LAS solution did not increase its biodegradability. Moreover, the effects of acclimated microorganisms on the biodegradability of the LAS solution were also studied. It was observed that the acclimated activated sludge increased the biodegradation of the LAS solution. However, due to the presence of some intermediates in the effluent of the photoreactor, the biodegradability of this effluent was less than the biodegradability of the untreated LAS solution with the same concentration of the LAS in the effluent of the photoreactor.

  14. Mineralization of Linear Alkylbenzene Sulfonate by a Four-Member Aerobic Bacterial Consortium

    Science.gov (United States)

    Jiménez, Luis; Breen, Alec; Thomas, Nikki; Federle, Thomas W.; Sayler, Gary S.

    1991-01-01

    A bacterial consortium capable of linear alkylbenzene sulfonate (LAS) mineralization under aerobic conditions was isolated from a chemostat inoculated with activated sludge. The consortium, designated KJB, consisted of four members, all of which were gram-negative, rod-shaped bacteria that grew in pairs and short chains. Three isolates had biochemical properties characteristic of Pseudomonas spp.; the fourth showed characteristics of the Aeromonas spp. Cell suspensions were grown together in minimal medium with [14C]LAS as the only carbon source. After 13 days of incubation, more than 25% of the [14C]LAS was mineralized to 14CO2 by the consortium. Pure bacterial cultures and combinations lacking any one member of the KJB bacterial consortium did not mineralize LAS. Three isolates carried out primary biodegradation of the surfactant, and one did not. This study shows that the four bacteria complemented each other and synergistically mineralized LAS, indicating catabolic cooperation among the four consortium members. PMID:16348496

  15. Investigating the Efficiency of UV/H2O2 Process for Removal of Linear Alkylbenzene Sulfonate (LAS in Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    R Nabizadeh Nodehi

    2011-01-01

    Full Text Available "n "nBackgrounds and Objective: Surfactants are one of the largest pollutants which exist in urban and industrial wastewaters. Large quantities of surfactants have entered to the environment since last decade due to increased use of synthetic detergent in industrial and home consumptions.In this study, the efficiency of UV/H2O2 process in removal of linear alkylbenzane sulfonate (LAS from aqueous solutions was investigated."nMaterials and Methods: In this study methylene blue active substane(MBASmethod and spectrometery were used to determine anion and residual surfactant respectively. In this study important variables were H2O2 concentration, initial concentration of surfactant, pH and duration of UV radiation. The effect of UV/H2O2 process on the degradation of LAS was analyzed statistically by using Multiple Linear Regression test."nResults: The resulted showed that after 20 minute, ultraviolet radiation solely removed 38.44 percent of Anionic detergent, Hydrogen peroxide showed no significant removal of detergent solution in the time course study. The efficiency of UV/H2O2 process in 10, 20 and 30 minute were to 86.2, 90 and 96.5 %, respectively."nConclusion: The results showed that the efficiency of ultraviolet radiation and hydrogen peroxide process in anionic detergent was not significant thoogh it was considerable in combination process (UV/H2O2.

  16. Atomistic simulation study of linear alkylbenzene sulfonates at the water/air interface

    Science.gov (United States)

    He, Xibing; Guvench, Olgun; MacKerell, Alexander D.; Klein, Michael L.

    2010-01-01

    Molecular Dynamics simulations with the CHARMM atomistic force field have been used to study monolayers of a series of linear alkylbenzene sulfonates (LAS) at the water/air interface. Both the numbers of carbon atoms in the LAS alkyl tail (1 to 11), and the position of attachment of the benzene ring on the alkyl chain have been varied. Totally 36 LAS homologues and isomers have been investigated. The surface tensions of the systems and the average tilt angles of the LAS molecules are found to be related to both the length and the degree of branching of the alkyl tails, whereas the solubility and mobility are mostly determined by the tail length. PMID:20614916

  17. LAS 共代谢降解菌的降解动力学研究%Study on degradation kinetics of co-metabolic biodegradation of linear alkylbenzene sulfonate strains

    Institute of Scientific and Technical Information of China (English)

    季瑞武; 周利; 冉治霖; 朱佳

    2016-01-01

    研究2株直链烷基苯磺酸钠( LAS)共代谢降解菌的降解动力学.分别对2株直链烷基苯磺酸钠共代谢降解菌克雷伯氏菌属(Klebsiella sp.)和肠杆菌属(Enterobacter sp.)进行研究,通过正交实验考察了其最佳降解条件,并进行降解动力学研究.当温度为30℃,pH值为7.5,装液量为50 mL时,最适合两株细菌降解LAS.其中菌株L-2在生长基质葡萄糖质量浓度为500 mg/L时,对50 mg/LLAS降解率为94.2%;菌株L-15在生长基质葡萄糖质量浓度为1000 mg/L时,对50 mg/LLAS降解率为92.2%;当LAS质量浓度在25~100 mg/L范围内,2菌株降解反应符合一级动力学特征.本研究可为全基质生活污水处理LAS废水提供一定的理论依据.%The degradation kinetics of co -metabolic biodegradation of two linear alkyl-benzene sulfonate ( LAS) strains was studied .Two bacterial strains which could degrade lin-ear alkylbenzene sulfonate by co -metabolism mechanism , named as L-2 and L-15 were determined to Klebsiella sp .and Enterobacter sp .The optimal degradation conditions of L -2 and L-15 were investigated by the orthogonal experiment .The results suggested that the degradation rate of LAS (50 mg/L) by L-2 was up to 94.2%when glucose was chosen as growth substrate under the conditions as:30 ℃, pH 7.5, glucose concentration 500mg/L, while the degradation rate of LAS (50 mg/L) by L-15 was up to 92.2%under the condi-tions as:30 ℃, pH=7.5, glucose concentration 1 000 mg/L.The degradation reactions fitted first order kinetics when the concentration of LAS ranged from 25 mg/L to 100 mg/L. Certain theoretical basis of the treatment of LAS wastewater was provided by this study .

  18. Removal of linear alkylbenzene sulfonates (LAS)in subsurface wastewater infiltration system%地下渗滤系统对直链烷基苯磺酸盐(LAS)的去除研究

    Institute of Scientific and Technical Information of China (English)

    潘晶; 宋思雨; 袁方; 费鹤馨; 李修月; 孙亦飞

    2015-01-01

    Linear alkylbenzene sulfonates (LAS)is a kind of organic pollutants that is most familiar and representative as to its environmental behavior and effect.The removal of LAS was studied in the subsurface wastewater infiltration system.The results showed that subsurface wastewater infiltration system had strong purifying function to LAS and its removal rate more than 90% when LAS concentration was between 0.56 and 40 mg/L.The removal rate of LAS increases with the increase of the concentration of LAS.The removal rate of COD,TP and IP decreased with the increase of concentration of LAS,meanwhile,the removal rate of NH+4 N had few change.The amount of bacteria,fungi and actinomyces decreased with the increase of concentration of LAS.LAS had no influence on the amount of nitrifying bacteria.The amount of denitrifying bacteria increased firstly and decreased finally.%直链烷基苯磺酸盐的广泛运用,使其成为环境中最常见的具有代表性的一类有机污染物,其环境行为与环境效应也受到普遍的关注。以生活污水中直链烷基苯磺酸盐为对象,研究了地下渗滤系统对其去除效果以及对其他污染物去除和基质微生物量的影响。结果表明:污水中直链烷基苯磺酸盐浓度在0.56~40 mg/L,地下渗滤系统对直链烷基苯磺酸盐的去除率达到90%以上;直链烷基苯磺酸盐去除率随着其浓度的增加而增加。随着直链烷基苯磺酸盐浓度的升高, COD、TN、TP和 IP的去除率下降,而 NH+4

  19. Ozone degradation of alkylbenzene sulfonate in aqueous solutions using a stirred tank reactor with recirculation.

    Science.gov (United States)

    Jurado-Alameda, Encarnación; Vicaria, José M; Altmajer-Vaz, Deisi; Luzón, Germán; Jiménez-Pérez, José L; Moya-Ramírez, Ignacio

    2012-01-01

    The degradation of linear alkylbenzene sulfonates (LAS) in aqueous solutions by ozone has been investigated. The ozonation process was performed in a stirred tank reactor with recirculation which simulates the clean-in-place process used in many industrial facilities. The gas-liquid mass transfer of ozone in a buffer solution at different temperatures (25-55°C) was also studied in the same device, revealing that ozone decomposition can be considered negligible under the experimental conditions assayed. The effect of the initial LAS concentration, temperature, and ozone concentration on the concentration of homologues and total LAS were analysed as a function of time. Both concentrations diminished with time, this effect being more significant when higher temperatures were assayed. The relative proportion of homologues shows that the homologues of higher chain length are degraded in a greater proportion than are the homologues with shorter chain lengths.

  20. In vitro biotransformation of surfactants in fish. Part I: linear alkylbenzene sulfonate (C12-LAS) and alcohol ethoxylate (C13EO8).

    Science.gov (United States)

    Dyer, Scott D; Bernhard, Mary Jo; Cowan-Ellsberry, Christina; Perdu-Durand, Elisabeth; Demmerle, Susanne; Cravedi, Jean-Pierre

    2008-06-01

    Developing regulatory activities (e.g., REACh, [DGEE. 2003. Directorates General Enterprise and Environment. The new EU chemicals legislation REACH. DG Enterprise, Brussels, Belgium. (http://www.europa.eu.int/comm/enterprise/reach/index_en.htm)]) will require bioaccumulation to be assessed for thousands of chemicals. Further, there is increasing pressure to reduce, refine or replace animal tests. Given this scenario, there is an urgent need to evaluate the feasibility of in vitro systems to supply data useful for bioaccumulation estimation. Subcellular and cellular hepatic systems were tested to determine the biotransformation of two surfactants: C12-2-LAS (2-phenyl dodecane p-sulfonate) and an alcohol ethoxylate C13EO8 (Octaethylene glycol monotridecyl ether). The subcellular systems tested were liver homogenates and microsomes from the common carp (Cyprinus carpio) and rainbow trout (Oncorhynchus mykiss). Cellular systems consisted of primary hepatocytes from the common carp (Cyprinus carpio) and PLHC-1 cells, hepatocarcinoma cells from the desert topminnow (Poeciliopsis lucida). All in vitro systems were exposed to radiolabeled test compounds and assayed for biotransformation using liquid scintillation and thin layer chromatographic methods. First-order kinetics were used to estimate rates of biotransformation. Bioconcentration of test materials in fish were predicted using an in vitro to in vivo metabolic rate extrapolation model linked to a mass-balance model commonly used to predict bioaccumulation in fish. Subcellular biotransformation rates for each of the surfactants were greatest with microsomes. Cellular loss rates exceeded subcellular rates, leading to lower predicted BCF values. Predicted BCFs corresponded closely to measured values in several fish species, verifying the utility of in vitro systems in refining Kow-only-based BCFs via the inclusion of biotransformation rates.

  1. Sorption of linear alkylbenzene sulfonate to soil components and effects on microbial iron reduction.

    Science.gov (United States)

    Kristiansen, Inge Broberg; de Jonge, Hubert; Nørnberg, Per; Mather-Christensen, Ole; Elsgaard, Lars

    2003-06-01

    When sewage sludge is applied to arable land, linear alkylbenzene sulfonate (LAS) is released into the environment. In soils, LAS has been shown to impede microbial processes, such as bacterial iron reduction. The aim of the present study was to quantify LAS adsorption and desorption to agricultural soils and iron oxides and relate this to the inhibition of microbial iron reduction. Two agricultural soils were used, namely, Askov (coarse sandy loam soil) and Lundgaard (coarse sandy soil). In both soils, LAS inhibited microbial iron reduction even at low LAS concentrations with 10% effect concentrations of 6 to 7 and 26 to 32 mg LAS/kg dry-weight soil for Lundgaard and Askov soil, respectively. The sorption isotherms showed that sorption of LAS to iron oxides was 10 to 100 times stronger than sorption to the agricultural soils. Also, it appeared that at low LAS concentrations (< 10 mg/kg dry-wt soil), Lundgaard soil adsorbed approximately 10 times more LAS than Askov soil. Thus, the inhibitory effect of LAS on microbial iron reduction was highest in the Lundgaard soil, which exhibited both the strongest sorption and the lowest desorption of the two soils. A possible hypothesis to explain this correlation was that LAS toxicity toward bacterial iron reduction was, at least partly, caused by LAS adsorbed to iron oxides, which could interfere with transfer of electrons between the bacteria and their respiratory electron acceptor.

  2. Effect of linear alkylbenzene sulfonate on population growth of Daphnia galeata: a life table evaluation.

    Science.gov (United States)

    Tanaka, Y; Nakanishi, J

    2001-01-01

    The chronic effect of linear alkylbenzene sulfonate (LAS12) on a daphnid species (Daphnia galeata) was examined by the life table experiment. The estimated responses in the intrinsic rate of population growth r were analyzed with two alternate concentration-response functions, i.e., the power function and the quadratic function. Based on the best-fit power function model with biases corrected by the jackknife procedure, the population-level EC50, which is defined as the concentration of chemicals that reduces the population growth rate (the intrinsic rate of natural increase) by 50%, was estimated as 2.5 mg/L. The 48-h acute immobility test yielded EC50 of 4.6 mg/L. The population-level effect of LAS12 on this test species is considerably more sensitive than the acute lethal effects to neonates.

  3. Fate of linear alkylbenzene sulfonate in agricultural soil columns during inflow of surfactant pulses

    Science.gov (United States)

    Boluda-Botella, N.; León, V. M.; Cases, V.; Gomis, V.; Prats, D.

    2010-12-01

    The transport and reaction processes of linear alkylbenzene sulfonate (LAS) were characterised in columns of agricultural soil with a constant inflow of irrigation water. A pulse input of commercial LAS was performed with different mixtures of soil and sea sand (0/100%, 25/75% and 50/50%) and a continuous water flow of approximately 0.5 mL/min. LAS homologue retention was favoured at a higher soil rate, due mainly to higher clay and organic matter contents. C 10LAS and C 11LAS were less retained in soil columns, and were eluted faster and in higher proportion through soil columns than other homologues. C 12LAS and C 13LAS showed stronger interactions with soil due to their higher sorption capacity, and a lower proportion was eluted than the lightest homologues. In general, sorption of LAS was reversible and significant fractions were desorbed when the LAS input ceased and they were transported to deeper layers in the soil column, especially for short-chain homologues. Longer LAS homologues were eluted from soil columns, but required an elution of >10 pore-volumes. When there was biodegradation in the soil column, >25% of LAS could be removed, reducing percolation to deeper layers.

  4. Linear alkylbenzene sulfonate and boron monitoring in four catchments in the UK contribution to GREAT-ER #11.

    Science.gov (United States)

    Holt, Martin S; Fox, Kay K; Daniel, Mic; Buckland, Harold

    2003-10-01

    A comprehensive monitoring programme was carried out in the Aire, Calder, Went and Rother catchments in the UK. A total of 804 effluent samples from 36 sewage treatment works (STWs) and 1100 water samples from 54 river sampling sites were analysed. Concentrations of linear alkylbenzene sulfonate (LAS), boron and other water quality determinands in STW effluent and river waters over a 2-year period (August 1996-August 1998) are reported. The data illustrate the temporal and spatial variations in concentrations of LAS and boron in river waters and effluents. Concentrations of LAS in effluents reflect the biological treatment employed and the influence of tertiary treatment is clearly demonstrated.

  5. Freely dissolved concentrations of anionic surfactants in seawater solutions: optimization of the non-depletive solid-phase microextraction method and application to linear alkylbenzene sulfonates.

    NARCIS (Netherlands)

    Rico Rico, A.; Droge, S.T.J.; Widmer, D.; Hermens, J.L.M.

    2009-01-01

    A solid-phase microextraction method (SPME) has been optimized for the analysis of freely dissolved anionic surfactants, namely linear alkylbenzene sulfonates (LAS), in seawater. An effect of the thermal conditioning treatment on the polyacrylate fiber coating was demonstrated for both uptake kineti

  6. Fate of the Benzene Ring of Linear Alkylbenzene Sulfonate in Natural Waters

    Science.gov (United States)

    Larson, R. J.; Payne, A. G.

    1981-01-01

    The biodegradability of linear alkylbenzene sulfonate (LAS) was studied in water samples collected from a receiving stream at locations above and below the discharge of a municipal wastewater treatment plant. Rates of primary biodegradation were determined for a commercial LAS mixture by a modified methylene blue-active substance method. Rates of LAS ultimate degradation were determined by radiochemical methods, using a C12 LAS homolog uniformly labeled with 14C in the benzene ring. The C12 LAS was tested at low concentrations (50 and 500 μg/liter) comparable to those existing in the receiving stream. Loss of methylene blue-active substance response over time occurred rapidly in water samples containing sediment collected from below the treatment plant, with an estimated half-life for LAS of 0.23 days. Evolution of 14CO2 during mineralization of the benzene ring occurred rapidly in the same samples, with a half-life for the benzene ring of 0.73 day. Mineralization of the benezene ring was also observed in river water containing no sediments and in river water and sediment samples collected from above the treatment plant. However, the rate of degradation was reduced in these cases, with half-lives for ring carbon ranging from 1.4 to 14 days. Although LAS degradation was enhanced in the presence of sediments, adsorption of LAS to the clay-silt fraction of river sediments was low, and most of the radioactivity was bound to biomass. PMID:16345731

  7. Influence of volatile fatty acid concentration stability on anaerobic degradation of linear alkylbenzene sulfonate.

    Science.gov (United States)

    Okada, Dagoberto Y; Delforno, Tiago P; Esteves, Andressa S; Polizel, Juliana; Hirasawa, Julia S; Duarte, Iolanda C S; Varesche, Maria B A

    2013-10-15

    Linear alkylbenzene sulfonate (LAS) is an anionic surfactant used in cleaning products, which is usually found in wastewaters. Despite the greater LAS removal rate related to a lower concentrations of volatile fatty acids (VFA), the influence of different ranges of VFA on LAS degradation is not known. LAS degradation was evaluated in upflow anaerobic sludge blanket (UASB) and expanded granular sludge bed (EGSB) reactors at different ranges of VFA concentrations. The reactors were fed with a synthetic wastewater containing LAS (14 mg/L). A greater LAS removal rate (40-80%) was related to the lower and narrower range of acetic acid concentration (1-22 mg/L) in the EGSB reactor. In the UASB reactor, the acetic acid concentrations presented a wider range (2-45 mg/L), and some low LAS removal rates (around 20-25%) were observed even at low acetic acid concentrations (<10 mg/L). The high recirculation rate in the EGSB reactor improved substrate-biomass contact, which resulted in a narrower range of VFA and greater LAS removal rate.

  8. Growth and antioxidant response in Hydrocharis dubis (Bl.) Backer exposed to linear alkylbenzene sulfonate.

    Science.gov (United States)

    Wu, Zhonghua; Yu, Dan; Li, Jinlin; Wu, Gongguo; Niu, Xiaona

    2010-04-01

    A two-week exposure experiment was designed to investigate the toxicity of linear alkylbenzene sulfonate (LAS) on the aquatic plant Hydrocharis dubis (Bl.) Backer, focusing on growth, photosynthetic pigments and the activities of antioxidant enzymes. No significant differences were observed in the growth parameters of H. dubis when H. dubis was exposed to lower LAS doses (10 mg l(-1)) resulted in significant decreases in all growth parameters of H. dubis. No significant effect on pigment contents was observed at up to 50 mg l(-1) LAS, beyond which pigment contents declined gradually. Malondialdehyde (MDA) content did not show obvious differences when H. dubis plants were exposed to LAS. Peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT) activities showed a concentration-dependent increase up to LAS concentrations of 0.1-10 mg l(-1), followed by a clear decrease. The results of this study suggest that LAS significantly inhibited the growth and physiology of H. dubis when the dose of LAS exceeded 10 mg l(-1) . Therefore, LAS at current environmental concentrations dose not appear to cause evident phytotoxic effects on H. dubis.

  9. Growth kinetics and toxicity of Enterobacter cloacae grown on linear alkylbenzene sulfonate as sole carbon source.

    Science.gov (United States)

    Khleifat, Khaled M; Tarawneh, Khaled A; Ali Wedyan, Mohammad; Al-Tarawneh, Amjad A; Al Sharafa, Khalid

    2008-10-01

    A successful attempt was made to isolate linear alkylbenzene sulfonate (LAS)-degrading bacteria from soil irrigated with wastewater. The isolated bacteria were able to use LAS as sole carbon and energy source. Maximum growth rates on LAS reached only 0.27 h(-1). 16S-rRNA sequencing and fatty-acid analysis placed the bacteria in the genus Enterobacter cloacae. The growth curves of E. cloacae both in the presence of and the absence of LAS were monitored using measurements of optical density at 600 nm in two different media, nutrient broth and M9 minimal medium, and were modeled mathematically. Growth in NB fit the Riccati and Voltera models, indicating that LAS is not toxic to E. cloacae cells. However, growth of E. cloacae in LAS-containing MM fit the Riccati and Voltera models, whereas growth in LAS-free MM fit the Riccati model only. Furthermore, the kinetic data shown were modeled by Monod's, Andrew's, and Tessier's specific growth rate equations, coupled with the rate of consumption of different concentrations of LAS as sole carbon and energy source, and we determined that Andrew's model best fit these data adequately as a result of the cell-inhibitory effect.

  10. Trace Determination of Linear Alkylbenzene Sulfonates: Application in Artificially Polluted Soil—Carrots System

    Science.gov (United States)

    Sablayrolles, Caroline; Montréjaud-Vignoles, Mireille; Silvestre, Jérôme; Treilhou, Michel

    2009-01-01

    Surfactants are widely used in household and industrial products. The risk of incorporation of linear alkylbenzene sulfonates (LAS) from biosolids, wastewater, and fertilizers land application to the food chain is being assessed at present by the European Union. In the present work, a complete analytical method for LAS trace determination has been developed and successfully applied to LAS (C10–C13) uptake in carrot plants used as model. These carrots were grown in soil with the trace organics compounds added directly into the plant containers in pure substances form. LAS trace determination (μg kg−1 dry matter) in carrots samples was achieved by Soxtec apparatus and high-performance liquid chromatography-fluorescence detection. The methodology developed provides LAS determination at low detection limits (5 μg kg−1 dry matter) for carrot sample (2 g dry matter) with good recoveries rate (>90%). Transfer of LAS has been followed into the various parts of the carrot plant. LAS are generally found in the carrot leaves and percentage transfer remains very low (0.02%). PMID:20107562

  11. Treatment of linear alkylbenzene sulfonate in a horizontal anaerobic immobilized biomass reactor.

    Science.gov (United States)

    Duarte, I C S; Oliveira, L L; Saavedra, N K; Fantinatti-Garboggini, F; Menezes, C B A; Oliveira, V M; Varesche, M B A

    2010-01-01

    Linear alkylbenzene sulfonate (LAS) is an anionic surfactant widely used to manufacture detergents and found in domestic and industrial wastewater. LAS removal was evaluated in a horizontal anaerobic immobilized biomass reactor. The system was filled with polyurethane foam and inoculated with sludge that was withdrawn from an up flow anaerobic sludge blanket reactor that is used to treat swine wastewater. The reactor was fed with easily degradable substrates and a solution of commercial LAS for 313 days. The hydraulic retention time applied was 12h. The system was initially operated without detergent and resulted to 94% reduction of demand. The mass balance in the system indicated that the LAS removal efficiency was 45% after 18 0days. From the 109 th day to the 254 th day, a removal efficiency of 32% was observed. The removal of LAS was approximately 40% when 1500 mg of LAS were applied in the absence of co-substrates suggesting that the LAS molecules were used selectively. Microscopic analyses of the biofilm revealed diverse microbial morphologies and denaturing gradient gel electrophoresis profiling showed variations in the total bacteria and sulfate-reducing bacteria populations. 16S rRNA sequencing and phylogenetic analyses demonstrated that members of the order Clostridiales were the major components of the bacterial community in the last step of the reactor operation.

  12. Biodegradation kinetics of linear alkylbenzene sulfonate in sludge-amended agricultural soils.

    Science.gov (United States)

    Ward, T E; Larson, R J

    1989-02-01

    The kinetics of ultimate biodegradation (mineralization to CO2) of linear alkylbenzene sulfonate (LAS) were studied in sludge-amended agricultural soils for a series of pure chain length LAS homologs containing 10 to 14 carbon atoms in the alkyl chain. Degradation rates were measured by following the production of 14CO2 from uniformly 14C-ring-labeled material. In general, degradation of LAS was rapid in soil over a broad concentration range (0.1 to 10 times the expected environmental concentration) and demonstrated little variation among different homologs. Half-lives for mineralization of the benzene ring ranged from 18 to 26 days and were not significantly different for any homolog over the range of alkyl chain lengths tested. Half-lives measured for LAS degradation in these studies were comparable to values reported in the literature and also to values obtained for naturally occurring materials (stearic acid, cellulose) typically present in soil environments. On the basis of the results of the present studies and those of other investigators, it is concluded that soil environments exposed to LAS in sewage sludges contain microbial communities which can actively metabolize this material. Rates of biodegradation of the benzene ring, the final step in the LAS biodegradation pathway prior to complete mineralization, are also sufficient to prevent LAS from accumulating in soil environments.

  13. Evaluation of the microbial diversity in sequencing batch reactor treating linear alkylbenzene sulfonate under denitrifying and mesophilic conditions using swine sludge as inoculum

    OpenAIRE

    2015-01-01

    The objective of this study was to evaluate the degradation of Linear Alkylbenzene Sulfonate (LAS) in anaerobic sequencing batch reactor (ASBR) under denitrifying conditions using swine sludge as inoculum. The reactor was operated for 104 days with synthetic substrate containing nitrate, and LAS was added later (22 mg/L). Considering the added mass of the LAS, the adsorbed mass in the sludge and discarded along with the effluent, degradation of the surfactant at the end of operation was 87%, ...

  14. Effects of Linear Alkylbenzene Sulfonate on Aggregation Behaviors of Titanium Dioxide Nanoparticles in Aqueous Environment

    Institute of Scientific and Technical Information of China (English)

    Xiuheng Wang

    2015-01-01

    In aqueous environment, organic matters may exert impacts on the aggregation behaviors of titanium dioxide nanoparticles ( TiO2⁃NPs). Owing to the deficiency of studies on the aggregation of TiO2⁃NPs in the presence of synthetic organic compound, this study used linear alkylbenzene sulfonate ( LAS) as a representative to evaluate the effects of TiO2⁃NPs concentration (1⁃10 mg/L), LAS concentration (0-1 mg/L), pH (4-8) and ionic strength ( NaCl, CaCl2; 5-20 mM ) during aggregation of TiO2⁃NPs suspensions based on the detection of hydrodynamic diameters and electrophoretic mobilities and the calculation of interaction energies. The results showed that the TiO2⁃NPs in the presence of LAS are more stable than that in the absence of LAS. With the increase of ionic strength, the hydrodynamic diameter of NPs decreases, and the existence of LAS changes the point of zero charge from 5�4 to a lower value and thus alteres the aggregation behaviors of TiO2⁃NPs. The present study suggests that the LAS has a significant impact to the transportation and transformation of nanoparticles in aqueous environment.

  15. Simultaneous removal of metal ions and linear alkylbenzene sulfonate by combined electrochemical and photocatalytic process.

    Science.gov (United States)

    Doan, H D; Saidi, M

    2008-10-30

    Combined electrochemical removal of Zn(++) and Ni(++) and photo-oxidation of linear alkylbenzene sulfonate (LAS) by suspended TiO(2) particles was investigated. The effect of different process variables such as current density, pH and liquid flow rate on the sole electrochemical reduction of metal ions was also evaluated. At pH of 5.0, the removal of Zn(++) increased by 28% with increases in the liquid flux from 0.0021 to 0.0172 m(3)m(-2)s(-1) while the removal of Ni(++) was only enhanced marginally. Under optimum operating conditions used in the present study (liquid flux=0.0172 m(3) m(-2) s(-1), current density=0.166 mA cm(-2), pH 5.0 and in the presence of LAS), Zn(++) and Ni(++) were reduced by 86 and 56%, respectively, over 7h of the sole electrochemical treatment. For the sole photocatalytic treatment of LAS at pH of 5.0, a 60% LAS degradation was obtained. However, the liquid flow rate did not have any considerable effect on the LAS oxidation. Finally, in the combined photocatalytic-electrolytic process, the LAS degradation increased to 76%. Nonetheless, in the combined system the Zn(++) and Ni(++) removal remained at comparable levels to those obtained in the sole electrochemical system.

  16. Biodegradation of linear alkylbenzene sulfonate in commercial laundry wastewater by an anaerobic fluidized bed reactor.

    Science.gov (United States)

    Braga, Juliana K; Motteran, Fabrício; Macedo, Thaís Z; Sakamoto, Isabel K; Delforno, Tiago P; Okada, Dagoberto Y; Silva, Edson L; Varesche, Maria Bernadete A

    2015-01-01

    The biodegradation of linear alkylbenzene sulfonate (LAS) from commercial laundry wastewater was evaluated in an anaerobic fluidized bed reactor (FBR) fed with synthetic substrate (598 mg L(-1) to 723 mg L(-1) of organic matter) supplemented with 9.5±3.1 mg L(-1) to 27.9±9.6 mg L(-1) of LAS. The average chemical oxygen demand (COD) removal efficiency was 89% and the biodegradation of LAS was 57% during the 489 days of anaerobic FBR. Higher levels of volatile fatty acids (VFA) were observed in the effluent at the stage with the best LAS removal performance. Increasing the surfactant concentration did not increase the VFA production in the effluent. The predominant VFAs after the addition of LAS were as follows: isovaleric acid and valeric acid, followed by propionic acid, caproic acid and formic acid. The similarities of 64% and 45% to Archaea and Bacteria domains were observed in the samples taken in the operating period of anaerobic FBR fed with 23.6±10 mg L(-1) and 27.9±10 mg L(-1) of LAS. During the operation stages in the reactor, Gemmatimonas, Desulfobulbus and Zoogloea were determined as the most abundant genera related to surfactant degradation using 454-Pyrosequencing.

  17. Influence of soil moisture on linear alkylbenzene sulfonate-induced toxicity in ammonia-oxidizing bacteria.

    Science.gov (United States)

    Nielsen, Klaus B; Brandt, Kristian K; Jacobsen, Anne-Marie; Mortensen, Gerda K; Sørensen, Jan

    2004-02-01

    Moisture affects bioavailability and fate of pollutants in soil, but very little is known about moisture-induced effects on pollutant toxicity. We here report on a modifying effect of moisture on degradation of linear alkylbenzene sulfonates (LASs) and on their toxicity towards ammonia-oxidizing bacteria (AOB) in agricultural soil. In soil spiked with two LAS levels (250 or 1,000 mg/kg) and incubated at four different moisture levels (9-100% of water-holding capacity), degradation was strongly affected by both soil moisture and initial LAS concentration, resulting in degradation half-lives ranging from 13 to more than 160 d. Toxicity towards AOB assessed by a novel Nitrosomonas europaea luxAB-reporter assay was correlated to total LAS concentration, indicating that LAS remained bioavailable over time without accumulation of toxic intermediates. Toxicity towards indigenous AOB increased with increasing soil moisture. The results indicate that dry soil conditions inhibit LAS degradation and provide protection against toxicity within the indigenous AOB, thus allowing for a rapid recovery of this population when LAS degradation is resumed and completed after rewetting. We propose that the protection of microbial populations against toxicity in dry soil may be a general phenomenon caused primarily by limited diffusion and thus a low bioavailability of the toxicant.

  18. Influence of plant growth on degradation of linear alkylbenzene sulfonate in sludge-amended soil.

    Science.gov (United States)

    Mortensen, G K; Egsgaard, H; Ambus, P; Jensen, E S; Grøn, C

    2001-01-01

    Widespread application of sewage sludge to agricultural soils in Denmark has led to concern about the possible accumulation and effects of linear alkylbenzene sulfonate (LAS) in the soil ecosystem. Therefore, we have studied the uptake and degradation of LAS in greenhouse pot experiments. Sewage sludge was incorporated into a sandy soil to give a range from very low to very high applications (0.4 to 90 Mg dry wt. ha(-1)). In addition, LAS was added as water solutions. The soil was transferred to pots and sown with barley (Hordeum vulgare L. cv. Apex), rape (Brassica napus L. cv. Hyola 401), or carrot (Daucus carota L.). Also, plant-free controls were established. For all additions there was no plant uptake above the detection limit at 0.5 mg LAS kg(-1) d.w, but plant growth stimulated the degradation. With a growth period of 30 d, LAS concentrations in soil from pots with rape had dropped from 27 to 1.4 mg kg(-1) dry wt., but in plant-free pots the concentration decreased only to 2.4 mg kg(-1) dry wt. When LAS was added as a spike, the final concentration in soil from planted pots was 0.7 mg kg(-1) dry wt., but in pots without plants the final concentration was much higher (2.5 mg kg(-1) dry wt.). During degradation, the relative fraction of homologues C10, C11, and C12 decreased, while C13 increased.

  19. Effect of nitrogen supplementation on aerobic degradation of linear alkylbenzene sulfonate by consortia of bacteria

    Directory of Open Access Journals (Sweden)

    Kehinde I. Temitope Eniola

    2012-05-01

    Full Text Available Untreated detergent bearing wastes discharged into the environment are sources of linear alkylbenzene sulfonate (LAS. Detergent wastes usually do not contain nitrogen or contain very low amounts. Biostimulation by introducing limiting nutrient element can be useful in biotreatment of such waste. The effect of inorganic and organic nitrogen supplements on aerobic degradation of LAS by LAS-utilizing bacteria was examined. Phosphate-buffered LAS mineral media were prepared and supplemented with different nitrogen sources: NPK fertilizer (inorganic and urea fertilizer (organic. Individual and various consortia of pure cultures of Alcaligenes odorans, Citrobacter diversus, Micrococcus luteus and Pseudomonas putida, previously isolated from a detergent effluent polluted stream, were used. Biodegradation of LAS was monitored in terms of half-life (t½ of the surfactant. The rates of biodegradation by the consortia can be ranked as: 4-membered (t½=8-12 days >3-membered (t½=8-13 days >2-membered consortia (t½=10-15 days >individuals (t½=9-16 days. The inorganic nitrogen source enhanced utilization of the surfactant, while organic nitrogen supplementation generally slowed degradation of the surfactant. In undertaking biotreatment of detergent bearing effluent, inorganic nitrogen should be used as biostimulant.

  20. Joint toxicity of linear alkylbenzene sulfonates and pyrene on Folsomia fimetaria.

    Science.gov (United States)

    Jensen, John; Sverdrup, Line E

    2002-05-01

    Surfactants may enhance the biodegradation of hydrophobic substances in soils. This has partly been attributed to an increase in the bioavailability, brought about by the presence of surfactants. The aim of this study was to examine the ecotoxicological effects of the detergent linear alkylbenzene sulfonate (LAS) and the polycyclic aromatic hydrocarbon pyrene, alone and in combination, using the survival and reproduction of the collembolan Folsomia fimetaria as endpoints. The EC(50) and EC(10) were 803 and 161 mg kg(-1) for LAS, and 23 and 15 mg kg(-1) for pyrene. If LAS was able to increase the bioavailability of pyrene to springtails, it was expected that the combined effect of the two substances would exceed the effect found for each of the compounds tested separately. However, the results showed no effect of LAS on the toxicity of pyrene in the concentration range tested (1-750 mg LAS kg(-1) dry weight). Both the toxic unit concept and the isobologram method indicated that an additive approach would be the most useful when assessing the risk of these two compounds.

  1. Colonized beads as inoculum for marine biodegradability assessment: application to linear alkylbenzene sulfonate.

    Science.gov (United States)

    Mauffret, Aourell; Rottiers, André; Federle, Thomas; Gillan, David C; Hampel, Miriam; Blasco, Julian; Temara, Ali

    2009-08-01

    An innovative biodegradation test system was developed in order to fill the current gap for cost effective and environmentally relevant tools to assess marine biodegradability. Glass beads were colonized by a biofilm in an open flow-through system of seawater with continuous pre-exposure to Linear Alkylbenzene Sulfonate (LAS) (20 microg/L). Thereafter, such colonized beads were added as inoculum in different test systems. [(14)C]-LAS (5-100 microg/L) was added and primary and ultimate biodegradation were assessed. The bacterial density collected on the beads (10(9) bact./mL beads) was ca. 3 orders of magnitude higher than the typical seawater content. The LAS mineralization lag phase duration decreased from 55 to <1 days and the mineralization extent increased from 53 to 90% as the colonized beads volume increased from 10 to 275 mL. This is the first demonstration of marine bacteria's ability to mineralize LAS. On the opposite, less than 13% LAS was mineralized in seawater only. The colonized beads possibly enhanced the probability to encounter the full degraders' consortium in a low volume of seawater (100 mL).

  2. The determination of the linear alkylbenzene sulfonate isomers in water samples by gas-chromatography/mass spectrometry.

    Science.gov (United States)

    Moldovan, Zaharie; Avram, Veronica; Marincas, Olivian; Petrov, Plamen; Ternes, Thomas

    2011-01-14

    A number of 20 compounds of linear alkylbenzene sulfonates (LASs) family were identified by electron impact mass spectrometry (EI-MS) in water samples collected from wastewater treatment plants (WWTP). This paper presents the mass spectra of 20 compounds, the proposed mechanism of formation of the diagnostic ions obtained by EI-MS and the distribution of individual isomers in water samples collected from compartments of WWTP. The individual isomers from four homolog series C(10)-, C(11)-, C(12)- and C(13)-LAS were analyzed as methyl derivatives.

  3. Liquid Phase Micro-Extraction of Linear Alkylbenzene Sulfonate Anionic Surfactants in Aqueous Samples

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    Jan Åke Jönsson

    2011-10-01

    Full Text Available Hollow fiber liquid phase micro-extraction (LPME of linear alkylbenzene sulfonates (LAS from aqueous samples was studied. Ion pair extraction of C10, C11, C12 and C13 homologues was facilitated with trihexylamine as ion-pairing agent, using di-n-hexylether as solvent for the supported liquid membrane (SLM. Effects of extraction time, acceptor buffer concentration, stirring speed, sample volume, NaCl and humic acids were studied. At 10–50 µg L−1 linear R2-coefficients were 0.99 for C10 and C11 and 0.96 for C12. RSD was typically ~15%. Three observations were especially made. Firstly, LPME for these analytes was unusually slow with maximum enrichment observed after 15–24 h (depending on sample volume. Secondly, the enrichment depended on LAS sample concentration with 35–150 times enrichment below ~150 µg L−1 and 1850–4400 times enrichment at 1 mg L−1. Thirdly, lower homologues were enriched more than higher homologues at low sample concentrations, with reversed conditions at higher concentrations. These observations may be due to the fact that LAS and the amine counter ion themselves influence the mass transfer at the water-SLM interface. The observations on LPME of LAS may aid in LPME application to other compounds with surfactant properties or in surfactant enhanced membrane extraction of other compounds.

  4. Liquid phase micro-extraction of linear alkylbenzene sulfonate anionic surfactants in aqueous samples.

    Science.gov (United States)

    Larsson, Niklas; Otrembska, Paulina; Villar, Mercedes; Jönsson, Jan Åke

    2011-10-13

    Hollow fiber liquid phase micro-extraction (LPME) of linear alkylbenzene sulfonates (LAS) from aqueous samples was studied. Ion pair extraction of C10, C11, C12 and C13 homologues was facilitated with trihexylamine as ion-pairing agent, using di-n-hexylether as solvent for the supported liquid membrane (SLM). Effects of extraction time, acceptor buffer concentration, stirring speed, sample volume, NaCl and humic acids were studied. At 10-50 µg L-1 linear R2-coefficients were 0.99 for C10 and C11 and 0.96 for C12. RSD was typically ~15%. Three observations were especially made. Firstly, LPME for these analytes was unusually slow with maximum enrichment observed after 15-24 h (depending on sample volume). Secondly, the enrichment depended on LAS sample concentration with 35-150 times enrichment below ~150 µg L-1 and 1850-4400 times enrichment at 1 mg L-1. Thirdly, lower homologues were enriched more than higher homologues at low sample concentrations, with reversed conditions at higher concentrations. These observations may be due to the fact that LAS and the amine counter ion themselves influence the mass transfer at the water-SLM interface. The observations on LPME of LAS may aid in LPME application to other compounds with surfactant properties or in surfactant enhanced membrane extraction of other compounds.

  5. Investigating the potential of using acoustic frequency on the degradation of linear alkylbenzen sulfonates from aqueous solution

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The effectiveness of using acoustical (sonochemical) reactor for degradation of linear alkylbenzen sulfonate (LAS) from aqueous solution was investigated. LASs are anionic surfactants, found in relatively high amounts in domestic and industrial wastewaters. In this study, experiments on LAS solution were performed using methylene blue active substances (MBAS) method.The effectiveness of acoustical processor reactor for LAS degradation is evaluated with emphasis on the effect of treatment time and initial LAS concentration. Experiments were performed at initial concentrations of 0.2, 0.5, 0.8 and 1.0 mg/L, acoustic frequency of 130 kHz, applied power of 500 W and temperature of 18 ℃~20 ℃. At the conditions involved, LAS degradation was found to increase with increasing sonochemical time. In addition, as the concentration increased, the LAS degradation rate decreased in the acoustical processor reactor.

  6. Microbial characterization and degradation of linear alkylbenzene sulfonate in an anaerobic reactor treating wastewater containing soap powder.

    Science.gov (United States)

    Carosia, Mariana Fronja; Okada, Dagoberto Yukio; Sakamoto, Isabel Kimiko; Silva, Edson Luiz; Varesche, Maria Bernadete Amâncio

    2014-09-01

    The aim of this study was to evaluate the removal of linear alkylbenzene sulfonate (LAS) in an anaerobic fluidized bed reactor (AFBR) treating wastewater containing soap powder as LAS source. At Stage I, the AFBR was fed with a synthetic substrate containing yeast extract and ethanol as carbon sources, and without LAS; at Stage II, soap powder was added to this synthetic substrate obtaining an LAS concentration of 14 ± 3 mg L(-1). The compounds of soap powder probably inhibited some groups of microorganisms, increasing the concentration of volatile fatty acids (VFA) from 91 to 143 mg HAc L(-1). Consequently, the LAS removal rate was 48 ± 10% after the 156 days of operation. By sequencing, 16S rRNA clones belonging to the phyla Proteobacteria and Synergistetes were identified in the samples taken at the end of the experiment, with a remarkable presence of Dechloromonas sp. and Geobacter sp.

  7. Environmental monitoring study of linear alkylbenzene sulfonates and insoluble soap in Spanish sewage sludge samples.

    Science.gov (United States)

    Cantarero, Samuel; Zafra-Gómez, Alberto; Ballesteros, Oscar; Navalón, Alberto; Reis, Marco S; Saraiva, Pedro M; Vílchez, José L

    2011-01-01

    In this work we present a monitoring study of linear alkylbenzene sulfonates (LAS) and insoluble soap performed on Spanish sewage sludge samples. This work focuses on finding statistical relations between LAS concentrations and insoluble soap in sewage sludge samples and variables related to wastewater treatment plants such as water hardness, population and treatment type. It is worth to mention that 38 samples, collected from different Spanish regions, were studied. The statistical tool we used was Principal Component Analysis (PC), in order to reduce the number of response variables. The analysis of variance (ANOVA) test and a non-parametric test such as the Kruskal-Wallis test were also studied through the estimation of the p-value (probability of obtaining a test statistic at least as extreme as the one that was actually observed, assuming that the null hypothesis is true) in order to study possible relations between the concentration of both analytes and the rest of variables. We also compared LAS and insoluble soap behaviors. In addition, the results obtained for LAS (mean value) were compared with the limit value proposed by the future Directive entitled "Working Document on Sludge". According to the results, the mean obtained for soap and LAS was 26.49 g kg(-1) and 6.15 g kg(-1) respectively. It is worth noting that LAS mean was significantly higher than the limit value (2.6 g kg(-1)). In addition, LAS and soap concentrations depend largely on water hardness. However, only LAS concentration depends on treatment type.

  8. Enhanced bioaccumulation of dietary contaminants in catfish with exposure to the waterborne surfactant linear alkylbenzene sulfonate.

    Science.gov (United States)

    Tan, Xiaobing; Yim, Sun-Young; Uppu, Prasanna; Kleinow, Kevin M

    2010-08-15

    Fish bioaccumulate a variety of contaminants and act as an exposure portal to the human consumer. Surfactants, known pharmaceutically to alter membrane permeability, change drug bioavailability and attenuate transporter function are also found in contaminant mixtures in the aquatic environment. The overall objective of this study was to determine if the surfactant C-12 linear alkylbenzene sulfonate (LAS) at environmentally relevant concentrations, alters the disposition and enhances bioaccumulation of co-exposed dietary xenobiotics in the catfish. Included for study were the carcinogen benzo(a)pyrene (BaP), pharmaceutical, ivermectin (IVM), and P-glycoprotein (P-gp) substrate rhodamine 123 (Rho-123), each exhibiting different dispositional footprints. Rho-123 transport into bile and membrane fluidity was examined in isolated perfused livers from control and LAS exposed catfish. Mass balance residue assessments were performed on catfish following in vivo exposure for 12 days to LAS in water at 0, 100 or 300 microg/L with 6 days of (3)H-IVM or (3)H-BaP gavage treatments. LAS at 1, 5 and 20 microM in the perfused liver, significantly decreased the transport of Rho-123 (1 microM) into bile by 18.6, 38.1 and 66.7%, respectively. Fluorescence anisotropy measurements demonstrated a 29.7% increase in fluidity at the (1 microM, 348 microg/L) LAS concentration. In vivo mass balance studies indicated that waterborne LAS (100 and 300 microg/L) increased the dietary dose remaining in fish by 39% and 78% for (3)H-IVM and 50 and 157% for (3)H-BaP. LAS at environmentally relevant concentrations altered the bioavailability and disposition of dietary xenobiotics in the catfish. Co-exposure with LAS increases xenobiotic bioaccumulation, potential toxicity of mixture components to the fish and the potential for residue transfer from fish to the consumer.

  9. Microbial community-level toxicity testing of linear alkylbenzene sulfonates in aquatic microcosms.

    Science.gov (United States)

    Brandt, Kristian K; Jørgensen, Niels O G; Nielsen, Tommy H; Winding, Anne

    2004-08-01

    Complex microbial communities may serve as ideal and ecologically relevant toxicity indicators. We here report an assessment of frequently used methods in microbial ecology for their feasibility to detect toxic effects of the environmentally important surfactant linear alkylbenzene sulfonate (LAS) on microbial communities in lake water and treated waste water. The two microbial communities were evaluated for changes in community structure and function over a period of 7 weeks in replicated aquatic microcosms amended with various levels of LAS (0, 0.1, 1, 10 or 100 mg l(-1)) and inorganic nutrients. In general, the two communities behaved similarly when challenged with LAS. Following lag periods of 1-3 weeks, LAS was degraded to non-toxic substances. Denaturing gradient gel electrophoresis of 16S rRNA gene fragments and [3H]leucine incorporation were the most sensitive assays with effect levels of 0-1 and 1-10 mg LAS l(-1), respectively. Community-level physiological profiles and pollution-induced community tolerance determinations using Biolog microplates demonstrated less sensitivity with effect levels of 10-100 mg LAS l(-1). Total cell counts and net uptake of inorganic N and P were unaffected even at 100 mg LAS l(-1). Interestingly, different microbial communities developed in some replicate microcosms, indicating the importance of stochastic events for community succession. We conclude that microbial community-level toxicity testing holds great promise and suggest a polyphasic approach involving a range of independent methods targeting both the structure and function of the tested microbial communities.

  10. Degradation and mobility of linear alkylbenzene sulfonate and nonylphenol in sludge-amended soil.

    Science.gov (United States)

    Jacobsen, Anne Marie; Mortensen, Gerda Krog; Hansen, Hans Christian Bruun

    2004-01-01

    Degradation and mobility of the surfactants linear alkylbenzene sulfonate (LAS) and nonylphenol (NP) were investigated in a lysimeter study using a sandy loam soil and 45-cm soil columns. Anaerobically digested sewage sludge was incorporated in the top-15-cm soil layer to an initial content of 38 mg LAS and 0.56 mg NP kg(-1) dry wt., respectively. Spring barley (Hordeum vulgare L.) was sown onto the columns. The lysimeters were placed outdoors and therefore received natural precipitation, but were also irrigated to a total amount of water equivalent to 700 mm of precipitation. Leachate and soil samples from three soil layers were collected continuously during a growth period of 110 d. Leachate samples and soil extracts were concentrated by solid-phase extraction (SPE) and analyzed using high performance liquid chromatography (HPLC) with fluorescence detection. The concentrations in the top-15-cm soil layer declined to 25 and 45% of the initial contents for LAS and NP, respectively, within the first 10 d of the study. At the end of the study, less than 1% LAS was left, while the NP content was below the detection limit. Assuming first-order degradation kinetics, half-lives of 20 and 37 d were estimated for LAS and NP, respectively. The surfactants were not measured in leachate samples in concentrations above the analytical detection limits of 4.0 and 0.5 microg L(-1) for LAS and NP, respectively. In addition, neither LAS nor NP were measured in concentrations above the detection limits of 150 and 50 microg kg(-1) dry wt., respectively, in soil layers below the 15 cm of sludge incorporation, indicating negligible downward transport of the surfactants in the lysimeters.

  11. Paramaterization of a coarse-grained model for linear alkylbenzene sulfonate surfactants and molecular dynamics studies of their self-assembly in aqueous solution

    Science.gov (United States)

    He, Xibing; Shinoda, Wataru; DeVane, Russell; Anderson, Kelly L.; Klein, Michael L.

    2010-02-01

    A coarse-grained (CG) forcefield for linear alkylbenzene sulfonates (LAS) was systematically parameterized. Thermodynamic data from experiments and structural data obtained from all-atom molecular dynamics were used as targets to parameterize CG potentials for the bonded and non-bonded interactions. The added computational efficiency permits one to employ computer simulation to probe the self-assembly of LAS aqueous solutions into different morphologies starting from a random configuration. The present CG model is shown to accurately reproduce the phase behavior of solutions of pure isomers of sodium dodecylbenzene sulfonate, despite the fact that phase behavior was not directly taken into account in the forcefield parameterization.

  12. Factors affecting linear alkylbenzene sulfonates removal in subsurface flow constructed wetlands.

    Science.gov (United States)

    Huang, Yuming; LaTorre, Ana; Barceló, Damià; García, Joan; Aguirre, Paula; Mujeriego, Rafael; Bayona, Josep M

    2004-05-01

    The behavior of linear alkylbenzene sulfonate (LAS) and sulfophenyl carboxylate (SPC) biointermediates in a pilot subsurface flow constructed wetland (SFCW) is reported for the first time. The effects of wetland configuration and operation on their treatment efficiency were investigated. The pilot SFCW constituted by eight beds of 55 m2 with different aspect ratios (1 x 1; 1.5 x 1; 2 x 1; 2.5 x 1), two water depths (i.e., 0.47 and 0.27 cm) at 5 cm below surface and two medium sizes (i.e., D60 = 10 mm and 3.5 mm) planted with Phragmites sp. That SFCW pilottreats urban wastewater (i.e., 200 inhabitants) and was operated at four hydraulic loading rates (HLRs) (20, 27, 36, and 45 mm d(-1)). Influent and effluent sampling was carried out from May 2001 to January 2002 with a weekly pattern. Main results were as follows: (i) water depth has a major influence on the performance of SFCW for the LAS removal, and HLR shows significant effect on SPC evolution; (ii) water temperature has a significant effect on the LAS evolution; (iii) biodegradation of LAS and SPC can occur under sulfate-reducing environment and mixed conditions (i.e., sulfate-reducing and denitrification), but aerobic respiration cannot be excluded; and (iv) C13 LAS homologues were generally removed in higher extent than the shorter alkyl chain counterparts. In the most appropriate conditions, LAS and SPC can be biodegraded up to 71% and 11%, respectively, in the pilot SFCW evaluated.

  13. Complete oxidation of linear alkylbenzene sulfonate by bacterial communities selected from coastal seawater.

    Science.gov (United States)

    Sigoillot, J C; Nguyen, M H

    1992-01-01

    Anionic surfactants, especially alkylbenzene sulfonates, are discharged into marine areas in great quantities. Because of their poor biodegradability, linear alkylbenzene sulfonates accumulate in seawater and sediments. Bacterial communities that can degrade surfactants were selected from coastal seawater contaminated by urban sewage. All the isolated strains consisted of gram-negative, strictly aerobic rods or helical bacteria. Some of these, though isolated from coastal seawater, did not need sodium for growth and appeared to be related to the genera Alcaligenes and Pseudomonas. Complete surfactant biodegradation was achieved by three important steps: terminal oxidation of the alkyl chain, desulfonation, and aromatic-ring cleavage. Only a few strains were able to carry out the first two steps. The aromatic ring was then cleaved by other strains that possess very specific enzymatic activities. Finally, a number of strains grew on short acids that were end-of-metabolism products of the others. PMID:1599249

  14. Identification of alkylbenzene sulfonate surfactants leaching from an acrylonitrile butadiene rubber as novel inhibitors of calcineurin activity.

    Science.gov (United States)

    Ito, Noboru; Shibuguchi, Nao; Ishikawa, Ryoki; Tanaka, Susumu; Tokita, Yoshiharu; Nakajima-Shimada, Junko; Hosaka, Kohei

    2013-01-01

    Calcineurin (CN) is a Ca(2+)/calmodulin (CaM) dependent serine/threonine protein phosphatase and plays important role in several cellular functions in both higher and lower eukaryotes. Here we report inhibition of CN by linear alkylbenzene sulfonate. The clue to the finding was obtained while identifying the inhibitory material leaching from acrylonitrile butadiene rubber used for packing. Using standard dodecylbenzene sulfonate (C12-LAS), we obtained strong inhibition of CN with a half maximal inhibitory concentration of 9.3 µM, whereas analogs such as p-octylbenzene sulfonate and SDS hardly or only slightly affected CN activity. Three alkaline phosphatases, derived from shrimp, bacteria, and calf-intestine, which exhibit similar enzymatic activities to CN, were not inhibited by C12-LAS at concentrations of up to 100 µM. Furthermore, C12-LAS did not inhibit Ca(2+)/CaM-dependent myosin light chain kinase activity when tested at concentrations of up to 36 µM. The results indicate that C12-LAS is a potent selective inhibitor of CN activity.

  15. Effect of linear alkylbenzene sulfonate on Cu(2+) removal by Spirulina platensis strain (FACHB-834).

    Science.gov (United States)

    Wang, Huili; Zhao, Xiaokai; Fang, Fang; Dahlgren, Randy A; Li, Dong; Yin, Xiaohan; Zhang, Yuna; Wang, Xuedong

    2014-10-01

    The removal efficiency of Cu(2+) by Spirulina platensis (strain FACHB-834), in viable and heat-inactivated forms, was investigated in the presence and absence of linear alkylbenzene sulfonate (LAS). When the initial Cu(2+) concentration was in the range of 0.5-1.5 mg · L(-1) , a slight increase in growth rate of FACHB-834 was observed. In contrast, when Cu(2+) or LAS concentrations were at or higher than 2.0 or 6.0 mg · L(-1) , respectively, the growth of FACHB-834 was inhibited and displayed yellowing and fragmentation of filaments. The presence of LAS improved Cu(2+) removal by ~20%, and accelerated attainment of Cu(2+) retention equilibrium. For the 2- mg · L(-1) Cu(2+) treatments, retention equilibrium occurred within 2 d and showed maximum Cu(2+) removal of 1.83 mg · L(-1) . In the presence of LAS, the ratio of extracellular bound Cu(2+) to intracellular Cu(2+) taken up by the cells was lower (1.05-2.26) than corresponding ratios (2.46-7.85) in the absence of LAS. The percentages of extracellular bound Cu(2+) to total Cu(2+) removal (both bound and taken up by cells) in the presence of LAS ranged from 51.2% to 69.3%, which was lower than their corresponding percentages (71.1%-88.7%) in the absence of LAS. LAS promoted biologically active transport of the extracellular bound form of Cu(2+) into the cell. In contrast, the addition of LAS did not increase the maximum removal efficiency of Cu(2+) (61.4% ± 5.6%) by heat-inactivated cells compared to that of living cells (59.6% ± 6.0%). These results provide a theoretical foundation for designing bioremediation strategies using FACHB-834 for use in surface waters contaminated by both heavy metals and LAS.

  16. Effects of linear alkylbenzene sulfonate on the growth and toxin production of Microcystis aeruginosa isolated from Lake Dianchi.

    Science.gov (United States)

    Wang, Zhi; Zhang, Junqian; Song, Lirong; Li, Enhua; Wang, Xuelei; Xiao, Bangding

    2015-04-01

    The exogenous organic pollutant linear alkylbenzene sulfonate (LAS) pollution and Microcystis bloom are two common phenomena in eutrophic lakes, but the effects of LAS alone on Microcystis remain unclear. In the present study, we investigated the effects of LAS on the growth, photochemical efficiency, and microcystin production of Microcystis aeruginosa in the laboratory. Results showed that low LAS (≤10 mg/L) concentrations improved the growth of M. aeruginosa (12 days of exposure). High LAS (20 mg/L) concentrations inhibited the growth of M. aeruginosa on the first 8 days of exposure; afterward, growth progressed. After 12 days of exposure, the concentrations of chlorophyll a in algal cells were not significantly affected by any of LAS concentrations (0.05 to 20 mg/L) in the present study; by contrast, carotenoid and protein concentrations were significantly inhibited when LAS concentrations reached as high as 20 mg/L. After 6 and 12 days of exposure, low LAS (≤10 mg/L) concentrations enhanced the maximal photochemical efficiency (Fv/Fm) and the maximal electron transport rate (ETRmax) of M. aeruginosa. Furthermore, LAS increased the microcystin production of M. aeruginosa. Extracellular and intracellular microcystin contents were significantly increased after M. aeruginosa was exposed to high LAS concentrations. Our results indicated that LAS in eutrophic lakes may increase the risk of Microcystis bloom and microcystin production.

  17. Toxic effects of linear alkylbenzene sulfonate on metabolic activity, growth rate, and microcolony formation of Nitrosomonas and Nitrosospira strains.

    Science.gov (United States)

    Brandt, K K; Hesselsøe, M; Roslev, P; Henriksen, K; Sørensen, J

    2001-06-01

    Strong inhibitory effects of the anionic surfactant linear alkylbenzene sulfonate (LAS) on four strains of autotrophic ammonia-oxidizing bacteria (AOB) are reported. Two Nitrosospira strains were considerably more sensitive to LAS than two Nitrosomonas strains were. Interestingly, the two Nitrosospira strains showed a weak capacity to remove LAS from the medium. This could not be attributed to adsorption or any other known physical or chemical process, suggesting that biodegradation of LAS took place. In each strain, the metabolic activity (50% effective concentration [EC(50)], 6 to 38 mg liter(-1)) was affected much less by LAS than the growth rate and viability (EC(50), 3 to 14 mg liter(-1)) were. However, at LAS levels that inhibited growth, metabolic activity took place only for 1 to 5 days, after which metabolic activity also ceased. The potential for adaptation to LAS exposure was investigated with Nitrosomonas europaea grown at a sublethal LAS level (10 mg liter(-1)); compared to control cells, preexposed cells showed severely affected cell functions (cessation of growth, loss of viability, and reduced NH(4)(+) oxidation activity), demonstrating that long-term incubation at sublethal LAS levels was also detrimental. Our data strongly suggest that AOB are more sensitive to LAS than most heterotrophic bacteria are, and we hypothesize that thermodynamic constraints make AOB more susceptible to surfactant-induced stress than heterotrophic bacteria are. We further suggest that AOB may comprise a sensitive indicator group which can be used to determine the impact of LAS on microbial communities.

  18. Bioremediation of surface water co-contaminated with zinc (II) and linear alkylbenzene sulfonates by Spirulina platensis

    Science.gov (United States)

    Meng, Huijuan; Xia, Yunfeng; Chen, Hong

    Potential remediation of surface water contaminated with linear alkylbenzene sulfonates (LAS) and zinc (Zn (II)) by sorption on Spirulina platensis was studied using batch techniques. Results show that LAS can be biodegraded by Spirulina platensis, and its biodegradation rate after 5 days was 87%, 80%, and 70.5% when its initial concentration was 0.5, 1, and 2 mg/L, respectively. The maximum Zn (II) uptake capacity of Spirulina platensis was found to be 30.96 mg/g. LAS may enhance the maximum Zn (II) uptake capacity of Spirulina platensis, which can be attributed to an increase in bioavailability due to the presence of LAS. The biodegradation rates of LAS by Spirulina platensis increased with Zn (II) and reached the maximum when Zn (II) was 4 mg/L. The joint toxicity test showed that the combined effect of LAS and Zn (II) was Synergistic. LAS can enhance the biosorption of Zn (II), and reciprocally, Zn (II) can enhance LAS biodegradation.

  19. Sorption-desorption kinetics and toxic cell concentration in marine phytoplankton microalgae exposed to Linear Alkylbenzene Sulfonate.

    Science.gov (United States)

    Renaud, Florent; Oberhänsli, François; Teyssié, Jean-Louis; Miramand, Pierre; Temara, Ali; Warnau, Michel

    2011-05-01

    Linear Alkylbenzene Sulfonates (LAS) are ubiquitous surfactants. Traces can be found in coastal environments. Sorption and toxicity of C(12)-LAS congeners were studied in controlled conditions (2-3500 μg C(12)LAS/L) in five marine phytoplanktonic species, using standardized methods. IC(50) values ranged from 0.5 to 2 mg LAS/L. Sorption of (14)C(12)-6 LAS isomer was measured at environmentally relevant trace levels (4μg/L) using liquid scintillation counting. Steady-state sorption on algae was reached within 5h in the order dinoflagellate>diatoms>green algae. The sorption data, fitted a L-type Freundlich isotherm, indicating saturation. Desorption was rapid but a low LAS fraction was still sorbed after 24h. Toxic cell concentration was 0.38±0.09 mg/g for the studied species. LAS toxicity results from sorption on biological membranes leading to non-specific disturbance of algal growth. Results indicate that LAS concentrations in coastal environments do not represent a risk for these organisms.

  20. Application of a linear alkylbenzene sulfonate biosensor to river water monitoring.

    Science.gov (United States)

    Nomura, Y; Ikebukuro, K; Yokoyama, K; Takeuchi, T; Arikawa, Y; Ohno, S; Karube, I

    1998-10-15

    A novel whole cell biosensor was constructed for the detection of anionic surfactants in aquatic environments. The analysis was rapid, convenient and did not require organic reagents. In this report, the application of this sensor to river water samples was investigated when applied to environmental samples; other organic substances present in river water may affect the measurement of linear alkylbenzene sulfonates. In order to deal with this problem, a correction system was developed using whole cells of Trichosporon cutaneum. This system was applied to in situ 24 h continuous monitoring in the Saka river.

  1. Formation of metabolites during biodegradation of linear alkylbenzene sulfonate in an upflow anaerobic sludge bed reactor under thermophilic conditions.

    Science.gov (United States)

    Mogensen, A S; Ahring, B K

    2002-03-05

    Biodegradation of linear alkylbenzene sulfonate (LAS) was shown in an upflow anaerobic sludge blanket reactor under thermophilic conditions. The reactor was inoculated with granular biomass and fed with a synthetic medium and 3 micromol/L of a mixture of LAS with alkylchain length of 10 to 13 carbon atoms. The reactor was operated with a hydraulic retention time of 12 h with effluent recirculation in an effluent to influent ratio of 5 to 1. A sterile reactor operated in parallel revealed that sorption to sludge particles initially accounted for a major LAS removal. After 8 days of reactor operation, the removal of LAS in the reactor inoculated with active granular biomass exceeded the removal in the sterile reactor inoculated with sterile granular biomass. The effect of sorption ceased after 185 to 555 h depending on the LAS homologs. 40% of the LAS was biodegraded, and the removal rate was 0.5 x 10(-6) mol/h/mL granular biomass. Acidified effluent from the reactor was subjected to dichloromethane extraction followed by gas chromatography/mass spectrometry. Benzenesulfonic acid and benzaldehyde were detected in the reactor effluent from the reactor with active granular biomass but not in the sterile and unamended reactor effluent. Benzenesulfonic acid and benzaldehyde are the first identified degradation products in the anaerobic degradation of LAS.

  2. Surfactant Linear Alkylbenzene Sulfonate Effect on Soil Cd Fractions and Cd Distribution in Soybean Plants in a Pot Experiment

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yong; LIAO Bo-Han; ZENG Qing-Ru; ZENG Min; LEI Ming

    2008-01-01

    A pot experiment was conducted to study the effect of an anionic surfactant linear alkylbenzene sulfonate (LAS) application on cadmium (Cd) fractious in soils and Cd distribution in different tissues of soybean (Glyeine max) plants as well as soil pH.Soil samples were treated with three levels of Cd (0,5,and 10 mg kg-1) and five levels of LAS (0,5,15,50,and 100 mg L-1).Results indicated that compared to the control soils (no Cd and no LAS treatment),soil pH increased and available Cd decreased in the soil treated with external Cd and watered with LAS solutions.Meanwhile,soil exchangeable Cd and Cd bound to carbonates decreased;Cd bound to amorphous iron and manganese oxides and Cd bound to organic matter increased.In addition,LAS application could reduce enrichment of Cd in soybean plants,resulting in decreased Cd in the soybean plants.Thus,suitable LAS application could decrease bioavailability and mobility of soil Cd.

  3. Effects of microcystin-LR, linear alkylbenzene sulfonate and their mixture on lettuce (Lactuca sativa L.) seeds and seedlings.

    Science.gov (United States)

    Wang, Zhi; Xiao, Bangding; Song, Lirong; Wu, Xingqiang; Zhang, Junqian; Wang, Chunbo

    2011-06-01

    Microcystin-LR (MCLR) and linear alkylbenzene sulfonate (LAS) are present widely in aquatic and terrestrial ecosystems, but their combined ecotoxicological risk is unknown. This study investigated the toxic effects of MCLR, LAS and their mixture on lettuce (Lactuca sativa L.) and evaluated MCLR accumulation level in lettuce with or without LAS. The changes in seed germination and shoot/root growth, responses of the antioxidative defense system, and the accumulation of MCLR in lettuce were tested to evaluate the single and combined toxic effect of MCLR and LAS in well-controlled conditions. The results showed that seedling growth (except for root elongation and leaf weight) was more sensitive to toxicant exposure than seed germination. For seedling leaves, lipid peroxidation was not observed when the antioxidative defense system (including superoxide dismutase, catalase and glutathione) was activated to relieve the adverse effects of oxidative stress via different pathways. Our results also confirmed that the interaction between MCLR and LAS was synergistic. Both toxicants in combination not only significantly inhibited seedling growth, but also increased the activities of superoxide dismutase and catalase, as well as the contents of glutathione. Furthermore, LAS dramatically enhanced the accumulation of MCLR in the plant, thus leading to a reduction in quality and yield and posing greater potential risk to humans via consumption of these edible plants.

  4. Kinetics of low frequency sonodegradation of linear alkylbenzene sulfonate solutions.

    Science.gov (United States)

    Abu-Hassan, Mohd A; Kim, Jung K; Metcalfe, Ian S; Mantzavinos, Dionissios

    2006-02-01

    The decomposition of sodium dodecylbenzene sulfonate (SDBS) in water by means of ultrasound irradiation at 20kHz was investigated. Experiments were conducted at surfactant concentrations of 175, 260 and 350 mg l(-1), liquid volumes of 120, 170 and 220 ml, temperatures of 20, 30 and 45 degrees C and applied power of 40, 80 and 125 W. The extent of degradation was followed monitoring substrate and organic carbon concentrations, while hydrogen peroxide concentration was also measured; the latter is a product of water sonolysis due to hydroxyl radical recombination. 80% SDBS conversion was achieved after 120 min of sonication at 125 W and 30 degrees C; nonetheless, SDBS and its degradation intermediates proved difficult to oxidise as only about 20-25% of the initial carbon content was transformed to carbon dioxide. At the initial stages of the reaction, degradation rate appears to be only weakly dependent on the substrate concentration with the rate increasing from 3.1 to 4 mg l(-1)min(-1) with increasing concentration from 175 to 350 mg l(-1). Degradation appears to occur at the bubble-liquid interface through hydroxyl radical-mediated reactions whose role was established by performing experiments in the presence of radical scavengers, namely potassium bromide and sodium benzoate. Degradation rates increased with increasing power and decreasing temperature and volume.

  5. Degradation of linear alkylbenzene sulfonate with contact glow discharge electrolysis

    Science.gov (United States)

    Budikania, Trisutanti; Ibrahim, Febiyanti, Irine Ayu; Utami, Nissa; Saksono, Nelson

    2015-12-01

    Contact Glow Discharge Electrolysis (CGDE) is one of electrolysis plasma technologies. CGDE can produce the hydroxyl radical in a large amount that can be used for wastewater degradation process. This study was conducted to obtain the influence of applied voltage, electrolyte concentration, and anode depth in the LAS degradation using CGDE and review its energy consumption. The greatest LAS degradation is achieved up to 99.14% with low energy consumption of 1149.88 kJ/mmol of the energy consumption that is obtained during 120 minutes by using 600 Volt, 0.02 M of KOH, and 0.5 cm of the anode depth and initial concentration of LAS is 100 ppm.

  6. Cytotoxic effect of linear alkylbenzene sulfonate on human intestinal Caco-2 cells: associated biomarkers for risk assessment.

    Science.gov (United States)

    Bradai, Mohamed; Han, Junkyu; El Omri, Abdelfatteh; Funamizu, Naoyuki; Sayadi, Sami; Isoda, Hiroko

    2014-09-01

    Linear alkylbenzene sulfonate (LAS) is a synthetic anionic surfactant widely present in the environment due to its intensive production and use in the detergency field. Admitting that current procedure of risk assessment has limits in providing realistic risk assessment data and predicting the cumulative effect of the toxicant mixtures, the incorporation of information regarding the mode of action and cell response mechanism seems to be a potential solution to overcome these limits. In this regard, we investigated in this study the LAS cytotoxicity on human intestinal Caco-2 cells, trying to unveil the protein actors implicated in the cell response using proteomics approach in order to give a better understanding of the toxicological effect and allow the identification of appropriate biomarkers reflecting the mode of action associated with LAS. As results, we demonstrated that LAS induces a time- and dose-dependent cytotoxicity in Caco-2 cells accompanied by an induction of oxidative stress followed by an excessive increase of intracellular calcium level. Proteomics approach helped in discovering three informative biomarkers of effect associated with LAS cytotoxic effect, reported for the first time: calreticulin, thioredoxin, and heat shock cognate 71 (HSP7C), confirmed by real-time PCR and western blot analysis. These biomarkers could serve for more reliable future risk assessment studies that consider the toxicants mode of action in order to help in the prediction of potential cumulative effects of environmentally coexisting contaminants.

  7. Investigation of an onsite wastewater treatment system in sandy soil: sorption and biodegradation of linear alkylbenzene sulfonate.

    Science.gov (United States)

    Doi, Jon; Marks, Kay H; DeCarvalho, Alvaro J; McAvoy, Drew C; Nielsen, Allen M; Kravetz, Louis; Cano, Manuel L

    2002-12-01

    The objective of this work was to determine the sorptive and biodegradable characteristics of linear alkylbenzene sulfonate (LAS) in a soil below a Florida, USA, septic system drainfield. Three distinct soil samples were collected from the septic system drainfield study site. These soils were used in laboratory sorption and biodegradation studies. Different concentrations of LAS were added, in radiolabeled and unlabeled forms, to a series of test vessels that contained upgradient groundwater and the soils collected from the study site. The sorption test was designed to determine the partitioning of LAS between groundwater and soil in each sample. Results indicated that the sorption distribution coefficient (Kd) decreased from 4.02 to 0.43 L/kg and that the rate of ultimate biodegradation (first-order rate constant, k1) decreased from 2.17 to 0.08/d with increasing distance (0.7-1.2 m vertically below ground surface [BGS] and 0 to 6.1 m horizontally) from the drainfield. The three soils showed 49.8 to 83.4% LAS mineralization (percentage of theoretical CO2) over 45- or 59-d test periods. These results demonstrate that subsurface soils in this system have the potential to sorb and biodegrade LAS.

  8. ISOLATION OF LINEAR ALKYLBENZENE SULFONATE(LAS)-DEGRADING BACTERIUM AND ITS DEGRADING CHARACTERS%直链烷基苯磺酸钠(LAS)降解菌的分离鉴定及其降解特性

    Institute of Scientific and Technical Information of China (English)

    尹静; 李君文; 王新为; 王福玉; 王景峰; 张斌; 晁福寰

    2005-01-01

    从天津市某洗涤剂生产厂的排水沟污泥中分离到一株对直链烷基苯磺酸钠(LAS)具有较强降解能力的菌株LAS1,经生理、生化、VITEK微生物自动鉴定仪以及分子生物学等方法鉴定,该菌为放射形土壤杆菌(Agrobacter Radiobacter).LAS1生长的最佳pH值为7.0,最适生长温度为30 ℃,无机氮可以促进其对LAS的降解,而有机氮则会对其降解LAS产生强烈竞争.当LAS浓度高于60 mg/L时,LAS1的LAS降解能力受到一定程度的抑制.LAS1对LAS的降解时间动力学曲线为二级动力学反应. 图4 参5

  9. 一个可降解直链烷基苯磺酸盐的新种%A New Species of the Genus Phenylobacterium for the Degradation of LAS (Linear Alkylbenzene Sulfonate)

    Institute of Scientific and Technical Information of China (English)

    柯娜; 肖昌松; 应启锋; 纪树兰

    2003-01-01

    本文鉴定了一株可完全降解直链烷基苯磺酸盐(Linear Alkylbenzene Sulphonate,简称LAS)的菌株GZ6.革兰氏染色阴性,细胞为杆状或短杆状,大小为0.5μm~0.8 μm×1.0μm~2.0 μm,其生长pH范围为pH6.0~10.0,最适生长pH为7.0,生长温度范围为4℃~40℃,最适生长温度为30℃.生化特征测定除过氧化氢酶、尿酶、精氨酸脱羧酶反应为阳性,其它均为阴性.可利用Chloridazon、安替比林(antipyrin)以及LAS等为碳源.不能利用大多数糖醇.醌组分以泛醌Q-10为主.菌体脂肪酸主要为C18∶1、C16∶0及C16∶1.DNA中G+C mol%含量为70.10.16S rRNA 序列分析表明菌株GZ6 与其亲缘关系最近的菌株Phenylobacterium immobile DSM1986T序列相似值为97.49%,DNA-DNA杂交率为40%.菌株GZ6具极生鞭毛,可运动,两者在细胞形态有很大差异.故将菌株GZ6定为苯基杆菌属的新种可动苯基杆菌(Phenylobaterium mobile) GZ6.

  10. Monitoring the primary biodegradation of linear alkylbenzene sulfonates and their coproducts in anoxic sediments using liquid chromatography-mass spectrometry.

    Science.gov (United States)

    Lara-Martín, Pablo A; Gómez-Parra, Abelardo; Köchling, Thorsten; Sanz, José Luis; González-Mazo, Eduardo

    2007-05-15

    An accompanying article has demonstrated the anaerobic degradation of the surfactant linear alkylbenzene sulfonate (LAS) in microcosms filled with marine sediments through the generation of sulfophenylcarboxylic acids (SPCs). A detailed study shows that this process was uniform in the blanks (non-spiked natural sediments) for every LAS homologue during the complete course of the experiment. However, when sediments were spiked with commercial LAS and, therefore, enriched with short-chain homologues, degradation was enhanced for these homologues until their percentages were close to those for non-spiked sediments. The reason is that short-chain homologues are more bioavailable due to their higher solubility and lower sorption capacity. Thus, sorption on sediments was found to be increased with the length of the alkyl chain for LAS homologues, following a linear Freundlich isotherm, whereas the metabolites generated were predominant in solution due to their much higher polarity. Intermediate-chain SPC homologues (C7-C9 SPCs) were the most abundant during the experiment, but a significant increase in the concentration of shorter-chain SPC homologues (C4-C6 SPCs) was detected toward the end. In the case of isomers, the steric effect of the aromatic group implies that LAS primary degradation took place preferentially over external isomers. Therefore, the generation of external isomers of SPCs was predominant during the complete experiment although internal isomers of SPCs became more evident when the degradation process had advanced and external isomers of LAS became scarce. The identity of both types of SPC isomer was confirmed by tandem mass spectrometry. With respect to LAS coproducts, the relative percentage of iso-LAS increased during the complete experiment and removal percentages for dialkyl tetralinsulfonates (<30%) were typically lower that those for LAS (66-79%), although a similar behavior was observed for their homologues in both cases.

  11. Evaluation of the microbial diversity in sequencing batch reactor treating linear alkylbenzene sulfonate under denitrifying and mesophilic conditions using swine sludge as inoculum

    Directory of Open Access Journals (Sweden)

    Iolanda Cristina Silveira Duarte

    2015-06-01

    Full Text Available The objective of this study was to evaluate the degradation of Linear Alkylbenzene Sulfonate (LAS in anaerobic sequencing batch reactor (ASBR under denitrifying conditions using swine sludge as inoculum. The reactor was operated for 104 days with synthetic substrate containing nitrate, and LAS was added later (22 mg/L. Considering the added mass of the LAS, the adsorbed mass in the sludge and discarded along with the effluent, degradation of the surfactant at the end of operation was 87%, removal of chemical oxygen demand was 86% and nitrate was 98%. The bacterial community was evaluated by cutting the bands and sequencing of polymerase chain reaction (PCR fragments and denaturing gradient gel electrophoresis (DGGE. The sequences obtained were related to the phylum Proteobacteria and the alpha-and beta-proteobacteria classes, these bacteria were probably involved in the degradation of LAS. The efficiently degraded LAS in the reactor was operated in batch sequences in denitrifying conditions.

  12. Toxicity of linear alkylbenzene sulfonate and one long-chain degradation intermediate, sulfophenyl carboxylic acid on early life-stages of seabream (sparus aurata).

    Science.gov (United States)

    Hampel, M; Blasco, J

    2002-01-01

    Seabream embryos (Sparus aurata) were exposed to various concentrations (0.05 to 10.0 mg L-1) of different homologues (C10 to C14) and a commercial mixture of linear alkylbenzene sulfonates (LAS), as well as one long-chain degradation intermediate, sulfophenyl carboxylic acid (SPC C11), to study the acute toxicity of these compounds. LAS homologues of higher chain length (C13 and C14) were proved to be more toxic than shorter species (C10, C11, and C12). LAS C13 and C14 provoked 100% lethality at concentrations of 0.1-0.25 mg L-1. On the other hand, shorter LAS homologues (chain length) did not produce any lethal effect at concentrations up to 5 mg L-1. In this work, results on the toxicity of a long-chain degradation intermediate of LAS, SPC C11, are presented. This compound did not produce any mortality at all the concentration ranges chosen.

  13. 应用拓扑指数预测直链烷基苯磺酸盐(LAS)的生物降解性%PREDICTION OF THE BIODEGRADABILITY OF LINEAR ALKYLBENZENE SULFONATE (LAS) USING TOPOLOGICAL INDEX

    Institute of Scientific and Technical Information of China (English)

    于涛; 刘先军; 丁伟; 刘娜; 方伟

    2005-01-01

    用拓扑方法研究了直链烷基苯磺酸盐(LAS)的生物降解性与分子结构的关系.根据分子结构的特点,用距离矩阵表征分子中原子基团的连接性.据此提出一个结构基础明确的定量关系式,可预测分子的生物降解性,以及表征LAS的结构-性质关系.对C10~C13LAS的计算结果表明,计算值与文献报道值较为一致.应用这一定量关系式,能够合理表征LAS的结构性能关系,且有助于揭示化合物结构与性能之间的关系.

  14. Accumulation and degradation of anionic surfactant linear alkylbenzene sulfonate (LAS) by Spirulina platensis%钝顶螺旋藻对阴离子表面活性剂(LAS)的富集与降解

    Institute of Scientific and Technical Information of China (English)

    李昊翔; 蒋小龙; 陈锋; 陈红

    2006-01-01

    实验考察了使用钝顶螺旋藻富集与降解溶液中的阴离子表面活性剂(LAS).结果表明,溶液中不同浓度LAS存在下,钝顶螺旋藻的生长符合逻辑斯谛克方程;钝顶螺旋藻对LAS具有一定的富集能力,当LAS的质量浓度为0.5、1、2 mg/L时,24 h时富集量达到最大,分别为2.43、4.83、10.12 mg/g;钝顶螺旋藻对LAS也具有一定的降解能力,当LAS的质量浓度分别为0.5、1、2 mg/L时,5 d内LAS的降解率分别为87%、80%和70.5%,其降解动力学方程可用二级反应动力学方程很好地拟合,拟合度达到87%以上.

  15. Evaluation of the microbial diversity in a horizontal-flow anaerobic immobilized biomass reactor treating linear alkylbenzene sulfonate.

    Science.gov (United States)

    Duarte, I C S; Oliveira, L L; Saavedra, N K D; Fantinatti-Garboggini, F; Oliveira, V M; Varesche, M B A

    2008-06-01

    The purpose of this work was to assess the degradation of linear alkylbenzene sulfonate (LAS) in a horizontal-flow anaerobic immobilized biomass (HAIB) reactor. The reactor was filled with polyurethane foam where the sludge from a sanitary sewage treatment was immobilized. The hydraulic detention time (HDT) used in the experiments was of 12 h. The reactor was fed with synthetic substrate (410 mg l(-1) of meat extract, 115 mg l(-1) of starch, 80 mg l(-1) of saccharose, 320 mg l(-1) of sodium bicarbonate and 5 ml l(-1) of salt solution) in the following stages of operation: SI-synthetic substrate, SII-synthetic substrate with 7 mg l(-1) of LAS, SIII-synthetic substrate with 14 mg l(-1) of LAS and SIV-synthetic substrate containing yeast extract (substituting meat extract) and 14 mg l(-1) of LAS, without starch. At the end of the experiment (313 days) a degradation of approximately 35% of LAS was achieved. The higher the concentration of LAS, the greater the amount of foam for its adsorption. This is necessary because the isotherm of LAS adsorption in the foam is linear for the studied concentrations (2 to 50 mg l(-1)). Microscopic analyses of the biofilm revealed diverse microbial morphologies, while Denaturing Gradient Gel Eletrophoresis (DGGE) profiling showed variations in the population of total bacteria and sulphate-reducing bacteria (SRB). The 16S rRNA gene sequencing and phylogenetic analyses revealed that the members of the order Clostridiales were the major components of the bacterial community in the last reactor operation step.

  16. Removal of linear alkylbenzene sulfonate from a small Yorkshire stream: contribution to GREAT-ER project #7.

    Science.gov (United States)

    Fox, K; Holt, M; Daniel, M; Buckland, H; Guymer, I

    2000-05-05

    An in-stream removal experiment has been carried out in Red Beck, a small stream which receives effluent from Shibden Head Sewage Treatment Works. This trickling filter works serves a purely domestic population of 9408 but is scheduled to be closed, and the flows diverted to another works, as part of Yorkshire Water's continuing capital investment programme. An anionic detergent, linear alkylbenzene sulfonate (LAS), boron, and standard water quality parameters have been measured at seven sites downstream of the effluent discharge point. Time of travel has been measured by detection of a fluorescent dye added to the effluent sampling chamber, and the increase in flow as the river proceeds through the catchment has been determined from current flow measurements, and from boron dilution data. Assuming a first order removal mechanism, the overall half-life for LAS removal is just over 2 h (2 h 14 min). Faster removal takes place in the upper portion of the stream, and removal over the last five sampling points is somewhat slower, with a half-life of 2 h 40 min. This removal may comprise both primary biodegradation and the deposition of suspended matter to which the surfactant has been adsorbed. There was no significant difference in the removal half-lives of the individual alkyl chain length homologues.

  17. Effects of linear alkylbenzene sulfonate(LAS) on the activities of superoxide dismutase and glutathione peroxidase in Spinibarbus sinensis%直链十二烷基苯磺酸钠对中华倒刺鲃SOD和GSH-Px的活性影响

    Institute of Scientific and Technical Information of China (English)

    杨帆; 孙翰昌

    2009-01-01

    To study the effects of anionic surfactants on antioxidant enzyme activities in fish, the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were determined in Spinibarbus sinensis after a 10 day exposure to three concentrations (0.01, 0.2 and 4.0 mg/L) of linear alkylbenzene sulfonate (LAS). The results showed that, investigation of SOD and GSH-Px in plasma and liver indicated that LAS exposure resulted in changes of the enzyme activities. Induction of the two enzymes in all tested tissues occurred in the initial exposure days, and then the enzyme activities decreased with the increase of LAS concentration (0.2 mg/L and 4.0 mg/L) and extension of exposure time(4?6?8? 10 d) , which suggested that the enzyme activities correlated to the LAS concentrations and the exposure times.%以中华倒刺鲃(Spinibarbus sinensis)暴露于不同浓度的直链十二烷基苯磺酸钠(LAS)中10 d,研究阴离子表面活性剂对鱼类抗氧化酶的影响.结果表明,亚致死浓度(4.9 mg/L)LAS暴露可导致中华倒刺鲃超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性发生变化.当LAS质量浓度为0.01 mg/L时,所有受检组织(血液、肝脏)的SOD和GSH-Px活性在暴露初期均受到不同程度的诱导,但LAS浓度为0.2 mg/L和4.0 mg/L和暴露时间超过4 d时,酶活性均呈明显的下降趋势,提示LAS暴露所引起的酶活性变化与暴露浓度和暴露时间有一定的相关性.

  18. Development of acute toxicity quantitative structure activity relationships (QSAR) and their use in linear alkylbenzene sulfonate species sensitivity distributions.

    Science.gov (United States)

    Belanger, Scott E; Brill, Jessica L; Rawlings, Jane M; Price, Brad B

    2016-07-01

    Linear Alkylbenzene Sulfonate (LAS) is high tonnage and widely dispersed anionic surfactant used by the consumer products sector. A range of homologous structures are used in laundry applications that differ primarily on the length of the hydrophobic alkyl chain. This research summarizes the development of a set of acute toxicity QSARs (Quantitative Structure Activity Relationships) for fathead minnows (Pimephales promelas) and daphnids (Daphnia magna, Ceriodaphnia dubia) using accepted test guideline approaches. A series of studies on pure chain length LAS from C10 to C14 were used to develop the QSARs and the robustness of the QSARs was tested by evaluation of two technical mixtures of differing compositions. All QSARs were high quality (R(2) were 0.965-0.997, p < 0.0001). Toxicity normalization employing QSARs is used to interpret a broader array of tests on LAS chain length materials to a diverse group of test organisms with the objective of developing Species Sensitivity Distributions (SSDs) for various chain lengths of interest. Mixtures include environmental distributions measured from exposure monitoring surveys of wastewater effluents, various commercial mixtures, or specific chain lengths. SSD 5th percentile hazardous concentrations (HC5s) ranged from 0.129 to 0.254 mg/L for wastewater effluents containing an average of 11.26-12 alkyl carbons. The SSDs are considered highly robust given the breadth of species (n = 19), use of most sensitive endpoints from true chronic studies and the quality of the underlying statistical properties of the SSD itself. The data continue to indicate a low hazard to the environment relative to expected environmental concentrations.

  19. Occurrence and fate of alkylphenol polyethoxylate degradation products and linear alkylbenzene sulfonate surfactants in urban ground water: Barcelona case study

    Science.gov (United States)

    Tubau, Isabel; Vázquez-Suñé, Enric; Carrera, Jesús; González, Susana; Petrovic, Mira; López de Alda, María J.; Barceló, Damià

    2010-03-01

    SummaryThis study investigates the fate of alkylphenol polyethoxylates (APEOs) degradation products (DPs) and the occurrence of linear alkylbenzene sulfonate (LAS) surfactants in urban ground water at field scale. The occurrence of APEOs DPs in ground water was studied in connection with: (1) sources of recharge or/and pollution containing these substances, (2) ground water redox conditions, (3) occurrence of LAS, which are currently the domestic surfactants more used in the study area and (4) other common contaminants in urban ground water in the city of Barcelona. The APEOs DPs analyzed included two nonylphenol carboxylates (NP2EC, NP1EC), two octylphenol carboxylates (OP2EC, OP1EC), nonylphenol (NP) and octylphenol (OP). The highest groundwater concentrations of APEOs DPs were detected in aquifers whose major source of recharge is a river receiving large amounts of effluents from secondary waste water treatment plants (WWTPs). In fact, APEOs DPs concentrations were above those in the river. NP2EC was the compound detected at highest concentrations. These increase with ammonium in samples with low dissolved oxygen. These degradation products were virtually absent in oxidizing aquifers whose main source of recharge is not the river. In this case, only the ultimate degradation product (NP) was detected, which suggests that parent compounds have degraded. These results indicate that APEOs are persistent or less degraded in reducing conditions, whereas they are degraded when oxidizing conditions prevail. By contrast, LAS concentrations were more than one order of magnitude lower than expected based on recharge sources in all (oxidizing and reducing) aquifers.

  20. Activity and population dynamics of heterotrophic and ammonia-oxidizing microorganisms in soil surrounding sludge bands spiked with linear alkylbenzene sulfonate: a field study.

    Science.gov (United States)

    Brandt, Kristian Koefoed; Krogh, Paul Henning; Sørensen, Jan

    2003-04-01

    Recent research has documented soil microorganisms to be rather sensitive to linear alkylbenzene sulfonates (LAS), which may enter the soil environment in considerable quantities following sewage sludge disposal. We here report field effects of LAS on selected microbial populations present in a sandy soil surrounding well-defined sludge bands spiked with high but realistic LAS levels (7.1 or 31.3 g/kg). Surprisingly, LAS had no effect on heterotrophic respiration in the sludge compartment per se but stimulated activity and metabolic quotient (microbial activity per unit of biomass) in the surrounding soil. By contrast, autotrophic ammonia oxidation was initially inhibited in the LAS-spiked sludge. This led to dramatic transient increases of NH4+ availability in the sludge and surrounding soil, subsequently stimulating soil ammonia oxidizers. As judged from a Nitrosomonas europaea bioluminescence toxicity assay, however, LAS or other sludge components never accumulated to toxic levels in the soil compartments and the LAS tolerance of the indigenous microbes further remained unchanged following LAS exposure. LAS effects on the investigated microbial populations largely occurred during the first two months and were confined to soil closer than 30 mm from LAS-spiked sludge. Our results strongly suggest that disposal of LAS-contaminated sludge does not pose a major risk to the function of the soil microbial community under field conditions.

  1. Toxicity of linear alkylbenzene sulfonate in anaerobic digestion: influence of exposure time.

    Science.gov (United States)

    Mösche, M; Meyer, U

    2002-07-01

    The inhibition of anaerobic digestion by the anionic surfactant linear alkylbenzene sulfonate was studied. The development of bacterial activity during several weeks was monitored by performing batch degradation tests with acetate and propionate. In the first phase the decay of activity without surfactant addition was studied. After the addition of the surfactant an immediate inhibition was detected. Subsequently, the degradation activity continued to decrease with increasing exposure time. Both, the immediate inhibition and the rate of the subsequent decrease of activity were dependent on the surfactant concentration. A kinetic model is presented that describes this behavior. A surfactant concentration of 14 mg L(-1) causes a 50% immediate inhibition of acetate degradation (27 mg L(-1) in the case of propionate degradation). Additionally, each 12 mg L(-1) of surfactant increases the decay rate of acetate degradation activity by a factor 10 (23 mg L(-1) for propionate degradation). A deviation from this model occurs at low surfactant concentrations (<3 mg L(-1)), where a slight stimulation of bacterial activity was observed. The above-mentioned concentrations refer to measured surfactant concentrations. These were substantially lower than the nominal concentrations (added surfactant per volume). This discrepancy is explained by adsorption of the surfactant to the biomass. Finally, the importance of the presented kinetic model and the significance of surfactant toxicity for anaerobic digestion are discussed.

  2. γ-H2AX induced by linear alkylbenzene sulfonates is due to deoxyribonuclease-1 translocation to the nucleus via actin disruption

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Xiaoxu; Toyooka, Tatsushi; Kubota, Toru; Yang, Guang; Ibuki, Yuko, E-mail: ibuki@u-shizuoka-ken.ac.jp

    2015-07-15

    Graphical abstract: - Highlights: • Non-genotoxic linear alkylbenzene sulfonates (LAS) generated γ-H2AX. • The γ-H2AX was not induced through direct LAS-induced DNA damage. • LAS weakened interactions between actin and DNase I. • Released DNase I translocated to nucleus and broke DNA strands, generating γ-H2AX. • This is a novel pathway for chemically induced γ-H2AX. - Abstract: Phosphorylation of histone H2AX (γ-H2AX) occurs following formation of DNA double strand breaks (DSBs). Other types of DNA damage also generate DSBs through DNA replication and repair, leading to the production of γ-H2AX. In the present study, we demonstrated that linear alkylbenzene sulfonates (LAS), the most widely used and non-genotoxic anionic surfactants, could generate γ-H2AX via a novel pathway. Breast adenocarcinoma MCF-7 cells were treated with five kinds of LAS with alkyl chains ranging from 10 to 14 carbon units (C{sub 10}–C{sub 14}LAS). The generation of DSBs and subsequent production of γ-H2AX increased in a manner that depended on the number of carbon units in LAS. γ-H2AX could also be generated with non-cytotoxic doses of LAS and was independent of the cell cycle, indicating the non-apoptotic and DNA replication-independent formation of DSBs. The generation of γ-H2AX could be attenuated by EGTA and ZnCl{sub 2}, deoxyribonuclease-1 (DNase I) inhibitors, as well as by the knockdown of DNase I. LAS weakened the interaction between DNase I and actin, and the enhanced release of DNase I was dependent on the number of carbon units in LAS. DNase I released by the LAS treatment translocated to the nucleus, in which DNase I attacked DNA and generated γ-H2AX. These results suggested that the LAS-induced generation of γ-H2AX could be attributed to the translocation of DNase I to the nucleus through the disruption of actin, and not to LAS-induced DNA damage.

  3. Assessment of the hemolysis and endothelial cell cytotoxicity induced by residual linear alkylbenzene sulfonates on pharmaceutical rubber stoppers based on HPLC-ESI-MS.

    Science.gov (United States)

    Li, Xianghui; Qiu, Lu; Li, Yueyue; Chen, Xiaofei; Zhu, Zhenyu; Chai, Yifeng

    2015-09-01

    This study was designed to develop a high-performance liquid chromatographic-electrospray ionization-mass spectrometry (HPLC-ESI-MS) method for quantitative determination of residual surfactant linear alkylbenzene sulfonate (LAS) compounds on pharmaceutical rubber stoppers. An HPLC-ESI-MS method was developed for separation and determination of five LAS homologs (C10-C14) under gradient conditions using methanol and ammonium acetate as mobile phases. Hemolysis activity of residual LAS compounds was analyzed by spectrophotometry. Expression of interleukin (IL)-6 and tumor necrosis factor (TNF)-α in human umbilical vein endothelial cells (HUVECs) after LAS compound treatment was examined by enzyme-linked sorbent assay. LAS compounds were well separated and determined by the established gradient conditions. The linear range was 0.05-8 µg/mL with correlation coefficients ≥0.997. Recoveries were from 73 to 134% and the relative standard deviation was <13.7%. There was a correlation between hemolysis rate and LAS compounds concentration when it was ≥0.8 µg/cm(2). LAS compounds decreased the viability of HUVECs and promoted the production of IL-6 and TNF-α. The developed analytical method was successful for quantitative determination of residual LAS compounds on pharmaceutical rubber stoppers and it is important to monitor and control the amount of LAS compounds on rubber stoppers.

  4. Research Progress in Determination Methods of Linear Alkylbenzene Sulfonate%直链烷基苯磺酸钠测定方法的研究现状

    Institute of Scientific and Technical Information of China (English)

    廖华

    2012-01-01

    对几种常用的测定直链烷基苯磺酸钠(LAS)方法如高效液相色谱法、荧光光度分析法、分光光度法、气相色谱法、电化学发光分析法等的研究进展进行了介绍.归纳出不同的测定方法所存在的问题及优势.%Research progress in determination methods of linear alkylbenzene sulfonate was introduced, such as high performance liquid chromatography, fluorescence spectrophotometry, spectrophotometric, gas chromatography, electrogenerated chemiluminescenc and so on. Advantages and disadvantages of different methods were discussed.

  5. Applying moving bed biofilm reactor for removing linear alkylbenzene sulfonate using synthetic media

    Directory of Open Access Journals (Sweden)

    Jalaleddin Mollaei

    2015-01-01

    Full Text Available Detergents and problems of their attendance into water and wastewater cause varied difficulties such as producing foam, abnormality in the growth of algae, accumulation and dispersion in aqueous environments. One of the reactors was designated with 30% of the media with the similar conditions exactly same as the other which had filling rate about 10 %, in order to compare both of them together. A standard method methylene blue active substance was used to measure anionic surfactant. The concentrations of linear alkylbenzene sulfonate which examined were 50, 100, 200, 300 and 400 mg/l in HRT 72, 24 and 8 hrs. The removal percentage for both of reactors at the beginning of operating at50 mg/l concentration of pollutant had a bit difference and with gradually increasing the pollutant concentration and decreasing Hydraulic retention time, the variation between the removal percentage of both reactors became significant as the reactor that had the filling rate about 30 %, showed better condition than the other reactor with 10 % filling rate. Ideal condition in this experiment was caught at hydraulic retention time about 72 hrs and 200 mg/l pollutants concentration with 99.2% removal by the reactor with 30% filling rate. While the ideal condition for the reactor with 10% filling rate with the same hydraulic retention time and 100 mg/l pollutants concentrations was obtained about 99.4% removal. Regarding anionic surfactant standard in Iran which is 1.5 mg/l for surface water discharge, using this process is suitable for treating municipal wastewater and industrial wastewater which has a range of the pollutant between 100-200 mg/l. but for the industries that produce detergents products which make wastewater containing more than 200 mg/l surfactants, using secondary treatment process for achieving discharge standard is required.

  6. STUDY ON THE DEGRADATION OF LINEAR ALKYLBENZENE SULFONATE BY IMMOBILIZED LAS1 STRAIN%固定化细胞技术降解直链烷基苯磺酸钠的实验研究

    Institute of Scientific and Technical Information of China (English)

    尹静; 李君文; 王新为; 王福玉; 王景峰; 张斌; 晁福寰

    2004-01-01

    目的探讨固定化细胞技术对直链烷基苯磺酸钠(LAS)降解效果及其影响因素,为含LAS废水的处理提供有效方法.方法以海藻酸钠作为从环境中筛选的LAS降解菌LAS1的固定化载体,通过摇床恒温培养观察其对LAS的降解效果.结果用固定化细胞技术降解直链烷基苯磺酸钠,其降解反应为一级动力学,最适降解温度为30℃,并具有较宽的pH值作用范围,在pH值5~9范围内其对LAS均有一定的降解效果,同时其耐受高浓度LAS的能力较悬浮态LAS1明显增强,当LAS浓度达到110 mg·L-1时仍具有98%的降解效果,在单位时间内降解LAS的能力是悬浮态LAS的5倍.结论固定化LAS1具有较强的LAS降解能力,其所需要的作用条件比较温和,具有应用于实际含LAS废水处理的前景.

  7. Decreases in surface activities and aquatic toxicities of linear alkylbenzene sulfonate and alcohol ethoxylates during biodegradation.

    Science.gov (United States)

    Oya, Masaru; Hisano, Noriko

    2010-01-01

    We discussed the relation between aquatic toxicity and interfacial activity during biodegradation with using LAS (Linear Alkylbenzene Sulphonate) and AE (Alcohol Ethoxylate). The change of death rate of Daphnia magna, surface tension, concentration of surfactant, and biodegradation by oxygen demand during biodegradation were measured. As a result, a rapid decrease in toxicity and rapid increase in surface tension were observed within the time before biodegradation based on oxygen demand started to increase. These rapid changes in toxicity and surface tension occurred due to the structural change of surfactant molecules in the primary biodegradation process, which was confirmed by HPLC (High Performance Liquid Chromatography) analysis. We also performed re-addition test to study the effects of acclimatization since it takes an important role on boidegradation, and found that the acclimatization significantly accelerated the primary biodegradation, which were indicated by increase in surface tension and decrease in aquatic toxicity. These results show that the environmental risk of surfactants should be considered not only with the biodegradation based on oxygen demand but also with the decrease of interfacial activity through the primary biodegradation process.

  8. The influence of a surfactant, linear alkylbenzene sulfonate, on the estrogenic response to a mixture of (xeno)estrogens in vitro and in vivo.

    Science.gov (United States)

    Harris, Catherine A; Brian, Jayne V; Pojana, Giulio; Lamoree, Marja; Booy, Petra; Marcomini, Antonio; Sumpter, John P

    2009-01-18

    The effect of the presence of a surfactant on the activity of a mixture of environmental estrogens was assessed. In their natural habitat, fish are subject not only to exposure to mixtures of estrogenic compounds, as has been addressed in previous publications, but also to other confounding factors (chemical, physical and biological), which may, in theory, affect their responses to such compounds. To assess the potential for such interference, the commonly occurring surfactant, linear alkylbenzene sulfonate (LAS), was applied to the yeast estrogen screen at various concentrations, independently and together with a mixture of estrogens at constant concentrations. LAS enhanced the estrogenic activity of the mixture, an effect which became less pronounced over the course of time. This information was used to design an in vivo study to assess induction of vitellogenin in fathead minnows exposed to the same mixture of estrogens plus LAS. A similar trend was observed, that is, the response was enhanced, but the effect became less pronounced as the study progressed. However, the enhanced response in vivo occurred only at the highest concentration of LAS tested (362microg/L), and was transient because it was no longer apparent by the end of the study. Although LAS is a significant contaminant in terms of both concentration and frequency of detection in the aquatic environment, these data do not suggest that it will have a significant impact on the response of fish to environmental estrogens.

  9. Incomplete degradation of linear alkylbenzene sulfonate surfactants in Brazilian surface waters and pursuit of their polar metabolites in drinking waters.

    Science.gov (United States)

    Eichhorn, Peter; Rodrigues, Silvana V; Baumann, Wolfram; Knepper, Thomas P

    2002-02-04

    In Brazil more than 90% of the population are not connected to municipal wastewater treatment plants. As a consequence, surface waters receive continuously considerable amounts of untreated domestic sewage containing surfactants as a major constituent. Such polluted waters gave rise to special interest if they are used as a source for the production of drinking water. In this work, the river Rio Macacu (State Rio de Janeiro, Brazil) was monitored for the occurrence of the most widely used anionic surfactant linear alkylbenzene sulfonate (LAS) together with its main degradative product, sulfophenyl carboxylates (SPC). In order to pursue the fate of both compounds after emission into the river, samples were collected at several locations along the river bank, and analyzed applying liquid chromatography-mass spectrometry after enrichment by solid-phase extraction. The LAS concentrations ranged between 14 and 155 microg l(-1) and the levels of their metabolic intermediates were found from 1.2 to 14 microg l(-1). The self-purification capacity of the water was impressively demonstrated in the upper course of the river downstream of a town considered as one major discharge point, whereas in the lower course the relative constant concentrations of both analytes were detected which was explained with an overall increasing level of pollution. Furthermore, a series of drinking water samples from Niterói and São Gonçalo, supplied by the same waterworks treating surface waters from the Rio Macacu, were taken during two sampling periods and examined for the presence of the strongly polar SPC which is suspected of by-passing the purification processes. The levels detected in the drinking water ranged between 1.6 and 3.3 microg l(-1). For the analyses of drinking and surface waters the peak pattern of a selected SPC homologue composed by several positional isomers served as an indicator to describe the progression of SPC degradation occurred in the river and could be used to

  10. Linear alkylbenzene sulfonate tolerance in bacteria isolated from sediment of tropical water bodies polluted with detergents.

    Science.gov (United States)

    Eniola, Kehinde I T; Olayemi, Albert B

    2008-12-01

    The discharge of untreated detergent-bearing waste introduces linear alklcylbenzene sulfonates (LAS) to the aquatic environment. The surfactant persists in some streams and rivers in Nigeria, some is adsorbed to suspended materials and end in the sediment of the receiving water bodies. In this study, bacteria isolated from sediments of some tropical detergent-effluent-polluted streams were tested for tolerance to LAS using the media dilution technique. LAS-tolerance was indicated by growth of the bacteria in the presence of the surfactant. The pH, concentrations of surfactant, population of heterotrophic bacteria and population of LAS-tolerant bacteria in the sediments were determined. A direct relationship (r = 0.9124) was found between the alkaline conditions (pH= 8.2-12.0) and high surfactant concentrations (45-132 mg/g) in the sediment. The sediments harboured a high population and a wide variety of bacteria; the populations of viable heterotrophic bacteria (VHB: 2.9 x 10(5) to 1.2 x 10(7) cfu/g) and LAS tolerant bacteria (LTB: 1.5 x 10(4) to 1.2 x 10(6) cfu/g) had a direct relationship (r = 0.9500). An inverse relationship resulted between each of them and the concentration of surfactant in the sediment, r(VHB/LAS) = -0.9303 and r(LTB/LAS) = -0.9143, respectively. Twelve bacteria species were isolated from the sediment: Alcaligenes odorans, Bacillus subtilis, Burkholderia cepacia, Citrobacter freundii, Citrobacter diversus, Escherichia coli, Micrococcus luteus, Micrococcus albus, Pseudomonas putida, Pseudomonas stutzeri, Staphylococcus aureus and Streptococcusfaecalis. Most of them were adapted to the surfactant with their maximum acceptable concentrations ranging between 0.03 and >1.0% (w/v). The sediments could serve as source of adapted organisms which can be used in bio-treatment of LAS-bearing waste.

  11. Analysis of linear alkylbenzene sulfonate homologues in environmental water samples by mixed admicelle-based extraction and liquid chromatography/mass spectrometry.

    Science.gov (United States)

    Lunar, Loreto; Rubio, Soledad; Pérez-Bendito, Dolores

    2006-07-01

    Hemimicelles and admicelles of cetyltrimethylammonium bromide (CTAB) and cetylpyridinium chloride (CPC), adsorbed onto silica, were tested as sorbents for the solid phase extraction (SPE) of linear alkylbenzene sulfonate (LAS) homologues from environmental water samples. LASs were quantitatively retained on both surfactants due to high hydrophobic and ionic interactions, which led to the formation of analyte-extractant mixed aggregates. Parameters affecting the SPE of LASs were optimised. Recoveries of analytes from wastewater influent and effluent and river water samples ranged between 86 and 110%. Combination of SPE with liquid chromatography/mass spectrometry provided detection limits for the different LAS homologues of about 4 ng L(-1). The precision of the method, expressed as relative standard deviation, ranged from 5 to 9%. The method was applied to the analysis of LASs in wastewater and river samples using sample volumes between 10 and 25 mL. The LAS concentrations found ranged from 9 to 503 microg L(-1). No cleaning step was required to get accurate results.

  12. Solid-phase contact assay that uses a lux-marked Nitrosomonas europaea reporter strain to estimate toxicity of bioavailable linear alkylbenzene sulfonate in soil.

    Science.gov (United States)

    Brandt, Kristian K; Pedersen, Anders; Sørensen, Jan

    2002-07-01

    Information about in situ toxicity of the bioavailable pools of adsorptive soil pollutants is a prerequisite for proper ecological risk assessment in contaminated soils. Such toxicity data may be obtained by assays allowing for direct exposure of introduced test microorganisms to the toxicants, as they appear in solid solution equilibria in the natural soil. We describe a novel sensitive solid-phase contact assay for in situ toxicity testing of soil pollutants based on a recombinant bioluminescent reporter strain of Nitrosomonas europaea. A slurry of the reporter strain and soil sample was shaken for 1 h, after which bioluminescence was measured either directly (soil slurry protocol) or in the supernatant obtained after centrifugation (soil extract protocol). The assay was validated for both protocols by using linear alkylbenzene sulfonate (LAS) as a toxic and adsorptive model compound in the soil samples. Interestingly, LAS showed the same toxicity to the reporter strain with either soil incubation (both protocols) or pure culture, suggesting that adsorbed LAS pools contributed to the observed toxicity. The solid-phase contact assay that used the reporter strain of lux-marked N. europaea was slightly more sensitive for the detection of LAS toxicity in soil than activity-based assays targeting indigenous nitrifiers and much more sensitive than assays targeting indigenous heterotrophic microbes. We conclude that the new solid-phase contact assay, which is based on direct interaction of the test microorganisms with bioavailable pools of the toxicants in soil, provides a most sensitive and relevant method for evaluating the in situ toxicity and assessing the risks of soil contaminants.

  13. Determination of Linear Alkylbenzene Sulfonates by High-Performance Liquid Chromatography%高效液相色谱法测定线性烷基苯磺酸钠

    Institute of Scientific and Technical Information of China (English)

    曹海燕; 张洁; 郭萍; 黄玉明

    2011-01-01

    A fast and efficient high performance liquid chromatographic (HPLC) method was established for the separation and analysis of LAS (linear alkylbenzene sulfonates) by separation on Symmetry C8 column and UV detection at 224 nm. The effects of methanol to water ratio in the mobile phase, salts and their concentrations and flow rate on LAS separation were tested and the optimal separation conditions were obtained as follows: methanol to water ratio of 77:23 (v/v), 0. 5 mmol/L CH3COONa and a flow rate of 0. 5 mL/min. The linear range for LAS homologues was 0. 20-23. 00 mg/L with RSD of less than 5%. The proposed method has been successfully applied to the analysis of LAS in natural water and wastewater with satisfactory results.%建立了高效快速的液相色谱法对线性烷基苯磺酸钠(linear alkylbenzene sulfonates,LAS)的分离测定方法.采用Symmetry C8柱分离,检测波长为224 nm.探讨了流动相中甲醇和盐的种类等对LAS分离效果的影响;优化后的LAS分离条件为:流动相中V(甲醇)∶ V(水)=77∶23且含有0.5 mmol/L无水CH3 COONa,流速为0.5 mL/min,LAS同系物的线性范围为0.20~23.00 mg/L,其相对标准偏差均小于5%.将该方法用于实际水样中LAS的分析,结果满意.

  14. The scale epithelium as a novel, non-invasive tool for environmental assessment in fish: Testing exposure to linear alkylbenzene sulfonate.

    Science.gov (United States)

    Alves, R M S; Pereira, B F; Ribeiro, R G L G; Pitol, D L; Ciamarro, C M; Valim, J R T; Caetano, F H

    2016-07-01

    Increasing pollution levels have turned our attention to assessing lethal and sublethal effects of toxic agents using the most informative techniques possible. We must seek non-invasive or non-lethal sampling methods that represent an attractive alternative to traditional techniques of environmental assessment in fish. Detergents are amongst the most common contaminants of water bodies, and LAS (Linear Alkylbenzene Sulfonate) is one of the most used anionic surfactant on the market. Our study analyzed morphological alterations (histological and histochemical) of the scale epithelium of Prochilodus lineatus under exposure to two concentrations of LAS, 3.6mg/L and 0.36mg/L, for a period of 30 days and evaluated at 14, 21 and 30 days. In order to establish morphological analysis of the scale epithelium as a new non-lethal environmental assessment tool that is reliable and comparable to classic methods, the relative sensibility of this technique was compared to a commonly used method of environmental assessment in fish, the estimation of the effects of pollutants upon branchial morphology. Two experiments were carried out, testing animals in tanks, and in individual aquariums. Results of analyses on gill tissue show that exposure to 3.6mg/L of surfactant caused severe damage, including hyperplasia, hypertrophy and fusion at 14 days, with aneurisms at 21 and 30 days; while exposure to 0.36mg/L had lighter effects on the organ, mainly lower incidence of fusion and hyperplasia. Aditionally, scale morphology was altered severely in response to 3.6mg/L of LAS, consistently showing increased mucous and club cell production. Epithelial thickness was the most variable parameter measured. Scale epithelium sensibility has the potential to be a reliable environmental marker for fish species since it has the advantage of being less invasive when compared to traditional methods. However, more studies are required to increase the robustness of the technique before it can be

  15. Large decrease in acute aquatic toxicity of linear alkylbenzene sulfonate in hard water and seawater by adding adsorbent.

    Science.gov (United States)

    Oya, Masaru; Takemoto, Yuka; Ishikawa, Yusuke

    2008-01-01

    LAS (Linear Alkylbenzene Sulphonate) shows relatively high aquatic toxicity in hard freshwater or seawater. In this paper, we studied the effect of adsorbent on the aquatic toxicity of LAS in hard freshwater and seawater. Daphnia magna and Artemia salina were used for acute aquatic toxicity test in freshwater and seawater, respectively. Kaolin was used as a model adsorbent and toxic surface tension (gamma(tox)) was used as an indicator of toxic condition. Results showed that the values of gamma(tox) of LAS to D. magna and A. salina were about 45-55 mN/m and 35-40 mN/m, respectively. Surface tension of LAS solution decreased and its aquatic toxicity increased with increasing the water hardness or the salinity. By adding adsorbent into the solutions, the surface activity and the aquatic toxicity were decreased greatly, and the effect of water hardness or salinity on surface tension and aquatic toxicity were removed. That is to say, the surface tension curve of soft freshwater corresponds with that of hard freshwater containing adsorbent and the surface tension curve at low salinity corresponds with that obtained for high salinity solutions containing the adsorbent. Therefore, our experimental data leads to the conclusion that the relatively high aquatic toxicity of LAS in concentrated solution of inorganic salts disappears in the presence of adsorbents. This is an important viewpoint in conducting environmental risk assessment of surfactants.

  16. Effect of laundry activities on in-stream concentrations of linear alkylbenzene sulfonate in a small rural South African river.

    Science.gov (United States)

    Gordon, A K; Muller, W J; Gysman, N; Marshall, S J; Sparham, C J; O'Connor, S M; Whelan, M J

    2009-07-15

    In many parts of the world clothes are washed near to or in rivers and streams. Little information is available on resulting concentrations of detergent ingredients or on any potential effects caused. In this study, the fate of a commonly used anionic surfactant, linear alkylbenzene sulphonate (LAS) was investigated in a reach of the Balfour River (Eastern Cape Province, South Africa) which was regularly used as a site for laundry activity. Samples of river water were collected upstream of the main washing site and at a number of locations downstream on several occasions in winter and summer. Sediment samples were also collected and analysed. In addition, a household survey was conducted to ascertain the amount of detergent used and the distribution of washing practices. The results of the survey suggested that the use of riverside locations for laundry activities was seasonal. Most washing tended to be done at home during the winter with riverside sites used more frequently during the summer months. The monitoring data showed that LAS concentrations in water were very variable. They were occasionally high in the immediate vicinity of the laundry site (up to 342 microg L(-1)) but were generally very low (effects are expected from LAS emissions at this site.

  17. The stability of non-ionic surfactants and linear alkylbenzene sulfonates in a water matrix and on solid-phase extraction cartridges.

    Science.gov (United States)

    Petrović, M; Barceló, D

    2000-12-01

    The stability of nonylphenol ethoxylates (NPEO), alcohol ethoxylates (AEO), coconut diethanol amides (CDEA) and linear alkylbenzene sulfonates (LAS) in a water matrix and preconcentrated on SPE cartridges was studied. A stability study was carried out in a water matrix (spiked ground water and real-world waste water) comparing different pretreatment procedures (addition of sulfuric acid to pH = 3, preservation with 1% and 3% of formaldehyde). When stored in a water matrix serious qualitative and quantitative changes occurred in waste water during the period of time studied (30 days). The losses of C12-C14 alcohol ethoxylates ranged from 72% to 88% when the sample was preserved with acid and from 17% to 86% when the sample was preserved with formaldehyde (3%). Simultaneously, an enrichment of the shorter alkyl chain homologues (C7EO and C10EO) was observed. The losses of NPEO were from 45% (sample preserved by acidification or by addition of 3% of formaldehyde) to 85% (sample preserved with 1% of formaldehyde). Additionally, an increase in concentration of polyethylene glycols (PEGs) and formation of different acidic forms, such as monocarboxylated (MCPEGs) and dicarboxylated polyethylene glycols (DCPEGs) were observed. The stability of surfactants preconcentrated on SPE cartridges was studied as a function of storage time and storage conditions (room temperature, 4 degrees C and -20 degrees C). The results indicate that disposable SPE cartridges can be recommended for the stabilization of non-ionic surfactants and LAS. Storage at -20 degrees C is feasible for long periods (up to 3 months for ground water and up to 2 months for waste water), while storage at 4 C can be recommended for a maximum of 1 month. When cartridges were kept at -20 degrees C the losses of AEOs (n = 12, 13 and 14), preconcentrated from waste water, ranged from 17 to 29% (after 60 days) and other compounds suffered small losses (maximum of 14% for C13LAS). At room temperature, after 7 days, the

  18. Study on efficiency of refractory linear alkyl-benzene sulfonates(LAS) removal from synthetic detergent wastewater by novel up-flow biological aerated filter%新型UBAF处理合成洗涤剂废水中降解LAS的效能研究

    Institute of Scientific and Technical Information of China (English)

    纪桂霞; 周步轩; 张欢; 刘弦

    2012-01-01

    通过在清水区悬挂生物绳软填料的上向流曝气生物滤池处理合成洗涤剂废水的试验,研究了水力负荷、气水比、污染负荷、滤层高度及溶解氧等对LAS处理效能的影响.结果表明:水力负荷、气水比及滤层厚度是新型UBAF处理效能的主要影响因素,进水污染负荷对LAS处理效能的影响不显著.废水LAS浓度与流经的滤层厚度存在很好的指数关系:Ch=C0ekh.新型UBAF的挂膜性能好,启动速度快,对COD、LAS的处理效能有一定提高.在水力负荷1.1 m3/(m2·h),气水比3∶1~4∶1的运行条件下,对典型合成洗涤剂废水中的LAS去除率达80%以上,处理水的LAS指标达到排放标准.%To improve the efficiency of up - flow biological aerated filter, fixed bio - cord in clarifying region was proposed and the novel system named NUBAF was applied on laboratory scale. Through study the effects of hydraulic loading, ratio of air to liquid, pollution load, media height and DO on linear alkyl - benzene sulfonates ( LAS) treatment performance using this new process and the results indicated that the hydraulic loading, ratio of air to liquid and media height were the main factors to the NUBAF performance , but the effect of the pollution load on the NUBAF performance was unremarkable. The removal efficiency of LAS could be up to 80 % under the optimal conditions; the hydraulic loading of 1. 1 mV (m2 ? H) , ratio of air to liquid of 3= 1 ~4: 1 (based on 3.3 mV (m2 ? H) :1. 1 m3/ (m2 ? H) ) , besides, there was an exponential relationship between the concentration of LAS and media height expressed as Ch = C0ekh. After treated by NUBAF, effluent was greatly improved to reach the discharge standards of China.

  19. Effect of Anionic Surfactant Linear Alkylbenzene Sulfonate(LAS) on Physiological and Biochemical Characteristics of Aquatic Plants%阴离子型表面活性剂(LAS)对水生植物生理生化特性的影响

    Institute of Scientific and Technical Information of China (English)

    刘红玉; 周朴华; 杨仁斌; 廖柏寒; 鲁双庆; 余苹中

    2001-01-01

    采用室内培养实验方法, 以植物的生长量、过氧化氢酶(CAT)和过氧化物酶(POD)活性变化作为观测指标,研究了直链烷基苯磺酸钠(LAS)对稀脉浮萍(Lemna paucicostata L.)、满江红(Azolla imbricata(Roxb.) Nakai)、水网藻(Hydrodictyon sp.)生理生化特性的影响. 结果表明,当 LAS浓度超过 1 mg@ L-1时,稀脉浮萍的生长受到严重抑制,在 10、100 mg@ L-1下,出现负增长. CAT、POD活性变化与细胞受伤程度直接相关,可作为植物分子生态毒理学指标. LAS浓度在 0-10 mg@ L-1范围内,随着浓度升高,酶活性增加,清除细胞中由于 LAS产生的过氧化物伤害; 当浓度超过 10 mg@ L-1时,植物受到明显损伤,甚至死亡. 同时发现, CAT、POD活性水平与植物的类群直接相关, 被子植物稀脉浮萍的酶活性比蕨类植物满江红的高,藻类植物水网藻酶活性最低.

  20. Effects of surfactant linear alkylbenzene sulfonate (LAS) on the growth of Zizania latifolia Turcz. and the residual LAS content in soil%表面活性剂对茭白生长影响及土壤残留分析

    Institute of Scientific and Technical Information of China (English)

    陈淑玲; 谭芸; 闫宁; 李建波; 寿森炎

    2010-01-01

    采用土培的试验方法,研究了在不同浓度阴离子表面活性剂--直链烷基苯磺酸钠(LAS)处理后,单季茭"美人茭"的生长、茭白叶片中叶绿素含量和抗氧化酶系统活性的变化情况,以及LAS在茭白叶片和土壤中的相对残留量.结果表明,10 mg·L-1、100 mg·L-1 LAS处理浓度对茭白的生长状态没有显著影响;1000 mg·L-1LAS处理浓度下美人茭株高和最大叶宽均分别低于对照25.5%(p<0.05)和27.0%(p<0.05),处理过程中叶绿素总含量大幅下降.10 mg·L-1、100 mg·L-1LAS处理浓度下美人茭的抗坏血酸过氧化物酶(APX)和过氧化氢酶(CAT)活性显著提高,1000 mg·L-1LAS处理浓度下美人茭的过氧化物酶(POD)活性受到严重的抑制.丙二醛(MDA)含量呈先上升后下降的趋势,并随着LAS处理浓度的升高而升高.茭白叶片中LAS残留量先下降后上升,10 mg·L-1处理浓度下美人茭叶片中LAS含量低;10和100mg·L-1处理浓度下土壤中LAS含量基本在0.1~0.5 mg·L-1之间,1000 mg·L-1处理浓度下土壤中LAS含量持续上升,达到2.0~3.0mg·L-1,且LAS含量在第28d比第7d时高54.0%(p<0.05).与单纯的土壤环境相比,茭白-土壤系统能够更有效地降低土壤中LAS含量.

  1. Degradation of linear alkylabenzene sulfonate (LAS) and its compounds in Donghu Lake (Hubei, P.R.C.) determined by high performance liquid chromatography (HPLC)

    Science.gov (United States)

    Ayfer, Yediler; Xu, Ying; Zhang, Yongyuan; Chen, Junjian

    1990-06-01

    Commercial linear alkylbenzene sulfonate (LAS), mixture of alkylchain lengths and phenyl position isomers (C10-C13), is widely used as a major constituent of household and industrial detergents in the People's Republic of China. Degradation process and behaviour of LAS compounds during an 82-hour lake water die-away study, with an added LAS concentration of 1.5mg·L-1, was quantified and accomplished by HPLO-UV after extractionon the SepPek C18 reversed-phase cartridges. The degradation rate became progressively faster with increasing chain length. The technique described in this study is fast, sensitive and specific, and can be used to determine low levels of LAS and for establishing water quality criteria and standards relating to LAS and its compounds.

  2. 一株高效降解直链烷基苯磺酸钠降解菌的分离鉴定及特性研究%Isolation and characterization of a bacteria strain with high efficiency to degrade linear alkylbenzene sulfonates

    Institute of Scientific and Technical Information of China (English)

    孙德坤; 赵海泉

    2011-01-01

    从合肥市王小郢污水处理厂的污泥中分离得到一株能高效降解直链烷基苯磺酸钠(linear alkylbenzene sulfonates,LAS)的菌株S1.通过对其形态特征、生理生化性质以及16s rDNA序列分析,鉴定菌株S1为人苍白杆菌(Ochrobactrum anthropi).对菌株S1降解LAS进行了研究,结果表明,菌株S1利用LAS生长的最适温度为30℃,最适pH值为7.0;菌株S1在LAS的浓度低于1 000mg·L-1的环境中,对LAS的降解率在80%以上;菌株S1在LAS浓度达到3 500mg·L-1环境中仍能生长.%A bacterial strain, S1, which is able to degrade linear alkylbenzene sulfonates (LAS) with high efficiency, was isolated from the sewage of Wangxiaoying wastewater treatment plant. According to its morpho logical and physiological properties and 16S rDNA sequence analysis, the bacteria strain was identified as Ochrobactrum anthropi. The optimum growth conditions for strain S1 were at 30℃ and pH 7.0, using LAS as sole carbon source. The degradation rate of strain S1 was higher than 80% when growing with LAS below 1 000 mg·L-1, and strain S1 could still grow with LAS above 3 500 mg·L-1.

  3. Effect of linear alkylbenzene sulphonate (LAS) on the mineralization, metabolism and uptake of 14C-phenanthrene in a model ecosystem (water-lava-plant-air).

    Science.gov (United States)

    Jiang, Xia; Yediler, Ayfer; Yufang, Song; Sun, Tieheng; Kettrup, Antonius

    2005-11-01

    The aim of this work was to evaluate the effect of linear alkylbenzene sulfonate (LAS, 200 mg l(-1)) on the fate of phenanthrene in a model ecosystem "water-lava-hydrophytes-air". The experiments were conducted using two closed cultivation chamber systems. Rushes (Juncus effesus) were selected as a representative hydrophyte. Five hundred micrograms per liter of phenanthrene in a culture solution containing a 14C-activity of 75 microCi per chamber was applied (i) to investigate the degradation of the labeled test substance and the transfer processes within the system; (ii) to determine the mass-balance possible and (iii) to detect the occurrence of volatile test substances, their volatile metabolites and the degradation end-product CO2 in the gas phase. Most of the applied 14C-activity was found in the plant (41-45%), in which approximately 95% was associated with plant roots and approximately 5% with shoots. The 14C-activity recovered in the form of VOCs and CO2 was measured in lava (18-29%, 8-11%), and in the culture solution (10-14% and 1%), respectively. Majority of the applied 14C-activity existed in two forms, i.e. (1) polar metabolites (26%), of which 91% were found in plant roots, and (2) un-extractable residues (23%), most of which were in plant roots (40%) and bounded to lava (58%). The presence of LAS significantly increased the volatilization of phenanthrene and its metabolites, inhibited its mineralization and decreased the level of 14C-activity in lava. Moreover, LAS reduced the phenanthrene level in plant roots.

  4. 直链烷基苯磺酸盐促进剩余污泥产生短链脂肪酸的研究%Improved short-chain fatty acids (SCFAs) production from waste activated sludge by linear alkylbenzene sulfonates (LAS)

    Institute of Scientific and Technical Information of China (English)

    姜苏; 陈银广; 周琪

    2007-01-01

    采用批试试验的方法研究了十二烷基苯磺酸钠(C12-LAS)对剩余污泥在厌氧发酵过程中产生的短链脂肪酸(SCFAs)的影响.结果表明,C12-LAS的投加极大地提高了剩余污泥厌氧发酵过程中的SCFAs产量.当C12-LAS加入量低于0.1g·g-1时,SCFAs产量随着C12-LAS加入量的增加而增加,然而,当C12-LAS加入量高于0.1g·g-1时,SCFAs产量反而有所降低.从污泥产酸量以及经济成本考虑,C12-LAS的最佳投加量为0.02g·g-1,此时剩余污泥的SCFAs最大产量出现在第6天.进一步的研究表明,C12-LAS不仅促使大量的碳水化合物和蛋白质脱离污泥颗粒并溶解到液相中,而且抑制了产甲烷菌的活性.尽管剩余污泥经历着酸化过程,但由于其释放出大量的NH4+-N,污泥在整个厌氧发酵过程中的pH值逐渐升高.

  5. Effects of Single and Complex Pollutions of Linear Alkylbenzene Sulfonates (LAS) and Cu2+ on Activities of SOD and CAT in Liver of Oriental Weatherfish Misgurnus anguillicaudatus%LAS与Cu2+单一及复合污染对泥鳅肝脏SOD、CAT活性的影响

    Institute of Scientific and Technical Information of China (English)

    陆雷达; 金叶飞; 施维林; 商科丹; 孙晓; 孙勇波

    2007-01-01

    采用暴露试验法研究了十二烷基苯磺酸钠(LAS)与Cu2+ 单一及复合污染对泥鳅肝脏超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性的影响.试验结果表明,单一LAS处理96 h后,SOD活性变化不显著,CAT在LAS为20.0 mg/L时被显著诱导(P<0.05);单一的Cu2+处理96 h后,泥鳅肝脏SOD、CAT活性受到显著影响(P<0.05),随着质量浓度的增加,表现为先诱导后抑制;LAS、Cu2+复合处理条件下,LAS为10.0 mg/L时,CAT、SOD活性分别在Cu2+质量浓度为0.05、0.10 mg/L时达到最低值,LAS为20.0 mg/L时,CAT、SOD活性有所回升,但其活性仍低于对照组,且差异均达到显著水平(P<0.01).通过比较,发现泥鳅肝脏CAT活性变化更能反映出污染物对泥鳅的毒性作用.

  6. Study of adjuvant effect of model surfactants from the groups of alkyl sulfates, alkylbenzene sulfonates, alcohol ethoxylates and soaps

    DEFF Research Database (Denmark)

    Clausen, S K; Sobhani, S; Poulsen, O M

    2000-01-01

    The sodium salts of representatives of anionic surfactants, dodecylbenzene sulfonate (SDBS), dodecyl sulfate (SDS) and coconut oil fatty acids, and a nonionic surfactant, dodecyl alcohol ethoxylate, were studied for adjuvant effect on the production of specific IgE antibodies in mice...... showed a statistically significant increase in OVA specific IgE levels. After two boosters, a statistically significant suppression in OVA-specific IgE production occurred with SDS (1000 mg/l), SDBS (1000 and 100 mg/l), coconut soap (1000 mg/l) and the alcohol ethoxylate (10 mg/l). This study suggests...

  7. Electrooxidation of Linear Alkyl Benzene Sulfonate (LAS) on Pt Electrodes

    OpenAIRE

    1999-01-01

    The electrochemical behaviour of linear alklybenzene sulfonate (LAS) on Pt electrodes was investigated in 0.05M Na2SO4 and in 0.1M NaCl at pH=8 by the potentiokinetic method and by electrolysis. The anodic and cathodic semilogarithmic current-potential curves were obtained between -1.6V - +1.6V. The experimental discharge potentials were determined by means of current-potential-curves obtained by electrolysis between 0-3V. The percentages of surface active material remaining in the so...

  8. Influence of support material on the immobilization of biomass for the degradation of linear alkylbenzene sulfonate in anaerobic reactors.

    Science.gov (United States)

    Lima de Oliveira, Lorena; Silveira Duarte, Iolanda Cristina; Sakamoto, Isabel Kimiko; Amâncio Varesche, Maria Bernadete

    2009-02-01

    Two horizontal-flow anaerobic immobilized biomass reactors (HAIB) were used to study the degradation of the LAS surfactant: one filled with charcoal (HAIB1) and the other with a mixed bed of expanded clay and polyurethane foam (HAIB2). The reactors were fed with synthetic substrate supplemented with 14 mg l(-1)of LAS, kept at 30+/-2 degrees C and operated with a hydraulic retention time (HRT) of 12h. The surfactant was quantified by HPLC. Spatial variation analyses were done to quantify organic matter and LAS consumption along the reactor length. The presence of the surfactant in the load did not affect the removal of organic matter (COD), which was close to 90% in both reactors for an influent COD of 550 mg l(-1). The results of a mass balance indicated that 28% of all LAS added to HAIB1 was removed by degradation. HAIB2 presented 27% degradation. Molecular biology techniques revealed microorganisms belonging the uncultured Holophaga sp., uncultured delta Proteobacterium, uncultured Verrucomicrobium sp., Bacteroides sp. and uncultured gamma Proteobacterium sp. The reactor with biomass immobilized on charcoal presented lower adsorption and a higher kinetic degradation coefficient. So, it was the most suitable support for LAS anaerobic treatment.

  9. 直链烷基苯磺酸钠对中国林蛙抗菌肽基因表达的影响%The Effects of Linear Alkylbenzene Sulfonate on Antimicrobial Peptide Genes Expression in Rana chensinensis

    Institute of Scientific and Technical Information of China (English)

    谢晖; 孙燕; 李治; 宋婧

    2011-01-01

    近年来由于生境丧失及环境污染等原因,中国林蛙野生种群急剧减少.为深入研究水体中普遍存在的阴离子表面活性剂直链烷基苯磺酸钠(linear alkylbenzene sulfonate,LAS)对中国林蛙生存的影响,通过急毒实验确定LAS对分别处于发育阶段26、32、42、46期的中国林蛙的半致死浓度.同时利用1、4、8 mg/L LAS处理不同发育阶段中国林蛙,研究LAS对中国林蛙存活率、发育状态的影响,并利用real-time PCR技术检测中国林蛙抗菌肽基因表达水平变化.结果表明,当处理时间为96 h,LAS浓度达到12.33 mg/L以上时会对不同发育阶段中国林蛙产生较为严重的致死效应.1~8 mg/L浓度范围的LAS虽然对中国林蛙存活和发育没有明显影响,但是改变了其抗菌肽基因表达模式.特别是中国林蛙胚后发育后期(32期)和变态期(42期),4~8 mg/L LAS会在不同程度上抑制prepropalustrin-2CE3 、preprobrevinin-2CE1和preprotemporin-1 CEd1抗菌肽基因表达.总体而言,高浓度LAS对中国林蛙免疫系统造成一定影响,可能使该物种更易受到致病菌的侵袭.研究结果为化学污染物对中国林蛙免疫系统影响积累了实验数据,同时为研究中国林蛙抗菌肽基因表达的调控通路提供一定的理论依据.%Rana chensinensis has been suffered from a dramatic reduction in recent years due to the losing of habitat, environmental pollution and so on. To understand the influence of linear alkylbenzene sulfonate (LAS), which is one of the most important pollutants in water environment, on the survival of Rana chensinensis, the median lethal concentration of LAS had been calculated by explosion of the frogs at stage 26, 32, 42, 46 in different concentrations of LAS. The effects of 1, 4, 8 mg/L LAS on the survival and development of Rana chensinensis at different stages were also investigated. Also, the expressions of antimicrobial peptide genes were detected by real-time PCR. The

  10. 直链烷基苯磺酸钠对雄性小鼠生精功能亚慢性毒性作用研究%Subchronic toxicity of linear alkylbenzene sulfonates to spermatogenic function in mice

    Institute of Scientific and Technical Information of China (English)

    张颖; 任春娥; 乔鹏云; 姜俊怡; 韩海艳; 王桂丽

    2012-01-01

    目的 探讨直链烷基苯磺酸钠(LAS)对雄性小鼠生精功能的亚慢性毒性作用及毒性遗留作用. 方法 NIH种雄性小鼠给予LAS(630 mg/kg,315 mg/kg)灌胃,每日1次,连续经口染毒2个月,同时设对照组.在第4、8周及停止染毒后4周进行精子形态学观察,光镜观察睾丸组织形态学变化,透射电镜观察睾丸超微结构变化. 结果 实验组与对照组相比,染毒4周后精子畸形率上升,畸形主要表现在颈部,精子中部胞浆小滴增多.染毒8周精子畸形率升高更显著.组织学检查实验组小鼠染毒4周时精细小管内各级精母细胞和精子细胞数减少,生精细胞排列紊乱,随实验时间延长及染毒浓度的增加此异常改变更显著;超微结构观察显示睾丸生精上皮内支持细胞、间质细胞、精原细胞线粒体广泛异常改变,呈时间及浓度依赖性.上述异常改变在停止染毒后4周无明显恢复. 结论 LAS对雄性小鼠生精功能亚慢性毒性作用及毒性遗留作用表现为:使生精上皮内支持细胞、间质细胞及精原细胞出现广泛线粒体空泡样变,精子胞浆小滴出现率升高.%Objectives: To investigate the subchronic toxicity of linear alkylbenzene sulfonates (LAS) to spermatogenic function in mice. Methods: NIH mice were treated with 630 mg/kg and 315 mg/kg (1/2, 1/4 LD50)of LAS per day for two months. The control mice were treated with normal sodium. Sperm morphology, testicular histomorphology and super-micro structure under electron transmission microscopy were assayed four and eight weeks after treatment. All the indexes were examined again after terminating the treatment of LAS for 4 weeks. Results: Compared to the control group, the percentages of deformed sperm and sperm cytoplasmic droplets significantly increased four weeks after treatment (F<0. 001) , and the increase was more obvious after eight weeks. The changes of testicular histomorphology under the microscope and

  11. Anaerobic treatment of sludge: focusing on reduction of LAS concentration in sludge

    DEFF Research Database (Denmark)

    Haagensen, Frank; Mogensen, Anders Skibsted; Angelidaki, Irini;

    2002-01-01

    Anaerobic degradation of linear alkylbenzene sulfonates (LAS) was tested in continuous stirred tank reactors (CSTR). LAS12 was used as a model compound and was spiked on sewage sludge. The experiments clearly showed that transformation of LAS12 occurred under anaerobic conditions. The degree...

  12. Integration of aquatic fate and ecological responses to linear alkyl benzene sulfonate (LAS) in model stream ecosystems.

    Science.gov (United States)

    Belanger, S E; Bowling, J W; Lee, D M; LeBlanc, E M; Kerr, K M; McAvoy, D C; Christman, S C; Davidson, D H

    2002-06-01

    An integrated model stream ecosystem fate and effect study of dodecyl linear alkylbenzene sulfonate (C(12)LAS) was performed in the summer and fall of 1996. The study addressed responses of periphytic microbes, immature benthic fauna including abundance, drift, and emergence of adult insects in a 56-day exposure. Exposures ranged from 126 to 2978 microg/L and were continuously presented in a single-pass, flow-through test system. Microbial heterotrophs acclimated to C(12)LAS exposure quickly (14 days) and biodegraded C(12)LAS at all concentrations. Blue-green algae responded by increasing in abundance with increasing C(12)LAS concentration. Invertebrates responded by increased drift and reduced benthic abundances at concentrations exceeding 293 microg/L. Emergence at 927 microg/L also declined relative to the control. Adverse responses for mayflies and chironomids were indicated using univariate statistical techniques. Multivariate techniques indicated these taxa plus mollusks, aquatic worms, caddisflies, and stoneflies were impaired at some concentrations. Bioavailability of C(12)LAS was investigated in streams as a function of the total suspended solid load in the water column driven by local weather and watershed patterns. A continuous bioavailability model indicated exposure was reduced by an average of 8.5+/-8.9%. A model ecosystem no-observed-effect concentration (NOEC) was concluded to be 293 microg/L based on measured water column exposure and adjusted to 268 microg/L by the bioavailability model. A literature review of 13 available model ecosystem studies was conducted and NOEC conclusions were adjusted by a structure-activity relationship to a dodecyl chain length (sulfophenyl position and distribution being ignored due to lack of information in the reviewed studies). Lentic studies (n=7) were found to have higher NOECs than lotic studies (n=6) and were more variable. Mean NOECs+/-SD for all studies, lentic studies only, and lotic studies only were 3320

  13. 茶多酚对直链烷基苯磺酸钠致小鼠皮肤损伤的保护作用%The Protective Effects of Tea Polyphenol on Injury of Skin Tissue of Mice Induced by Linear Alkylbenzene Sulfonate

    Institute of Scientific and Technical Information of China (English)

    赵文红; 崔慧娴; 孙倩男; 陈兵兵

    2016-01-01

    本研究主要探讨茶多酚(Tea polyphenol,TP)对直链烷基苯磺酸钠(Linear alkylbenzene sulfonate, LAS)引起小鼠皮肤组织损伤的保护作用。将50只健康昆明种雄性小鼠随机分为5组,每组10只,分别为正常对照组、TP 对照组(TP 100 mg·L-1)、LAS 损伤组(LAS 300 mg·L-1)、TP 干预组1(LAS 300 mg·L-1,TP 100 mg·L-1)与干预组2(LAS 300 mg·L-1,TP 200 mg·L-1)。分别用蒸馏水及不同剂量的 LAS 及 TP 涂抹小鼠的背部剃毛处,连续涂抹60 d,观察各组小鼠的饮食、日常活动及体质量变化情况;取背部涂抹皮肤进行 HE 及 Masson染色观察皮肤组织结构及胶原纤维变化情况;检测皮肤中丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、羟脯氨酸(Hyp)及小鼠血清中乳酸脱氢酶(LDH)、一氧化氮(NO)水平。结果表明,TP 干预可拮抗 LAS 引起的小鼠皮肤组织氧化应激及胶原改变;从第6周开始,干预组小鼠体质量增长显著高于 LAS 损伤组(P<0.01);皮肤形态结构有所改善,表皮厚度增加且较为完整,胶原纤维含量增加,纤维排列杂乱、松散、模糊的现象得到改善;皮肤中 SOD、GSH-Px 及 Hyp 水平明显增加,MDA 含量显著减少(P<0.01);血清中 LDH、NO 水平显著低于 LAS 损伤组(P<0.01)。实验结果表明 TP 在一定程度上对 LAS 所致小鼠皮肤的损伤有保护作用。%The objective of the study is to investigate the protective effects of tea polyphenol (TP) on injury of skin tissue of mice induced by linear alkylbenzene sulfonate (LAS). Fifty healthy Kunming mice (male) were randomly divided into 5 groups including normal control group (NC), TP control group (TPC), LAS-injury group (LAS, 300 mg·L-1), TP-intervention group 1 (LAS 300 mg·L-1, TP 100 mg·L-1) and TP-intervention group 2 (LAS 300 mg·L-1, TP 200 mg·L-1) respectively (n=10). The skins

  14. Activity and population dynamics of heterotrophic and ammonia-oxidizing microorganisms in soil surrounding sludge bands spiked with linear alkylbenzene sulfonate

    DEFF Research Database (Denmark)

    Brandt, K. K.; Sørensen, J.; Krogh, P. H.

    2003-01-01

    bioluminescence toxicity assay, however, LAS or other sludge components never accumulated to toxic levels in the soil compartments and the LAS tolerance of the indigenous microbes further remained unchanged following LAS exposure. LAS effects on the investigated microbial populations largely occurred during...

  15. Suitability of the marine prosobranch snail Hydrobia ulvae for sediment toxicity assessment: A case study with the anionic surfactant linear alkylbenzene sulphonate (LAS).

    Science.gov (United States)

    Hampel, M; Moreno-Garrido, I; González-Mazo, E; Blasco, J

    2009-05-01

    Individuals of the mudsnail Hydrobia ulvae (Pennant) (Mollusca: Prosobranchia) were exposed to sediments spiked with increasing concentrations (1.59-123.13mgkg(-1) dry weight) of the anionic surfactant linear alkylbenzene sulphonate (LAS) which is employed in the formulation of laundry powders and liquids, as well as hand dishwashing products. The suitability of the selected organism, H. ulvae for routine sediment toxicity testing was evaluated by measuring acute toxicity recording survival. Sublethal toxicity was evaluated as total number of produced veliger larvae per treatment throughout the test (9d). Mortality has shown to be a reliable and reproducible indicator of acute toxicity. LC(50) values were comprised between 203.4 (48h) and 94.3mgkg(-1) (9d) dry weight. As sublethal endpoint, the total number of produced larvae showed to be a useful indicator of toxicity for this organism. The number of produced larvae increased at lower exposure concentrations, whereas at the highest LAS concentration, the number of produced larvae decreased. This is the first report of acute and sublethal toxicity of sediment associated LAS for this species.

  16. ESI- MS and CAD- MS- MS Characterization of Alkylbenzene Sulfonates%烷基苯磺酸盐的电喷雾离子化质谱和碰撞活化解离质谱-质谱分析

    Institute of Scientific and Technical Information of China (English)

    刘兰珍; 王瑛; 吕强; 李培基; 朱善农

    2001-01-01

    The alkylbenzene sulfonates (ABS) have been identified by positive, negative ions electrospray ionization(ESI) coupled with collision activated dissociation(CAD) MS methods. Fragment ion peaks for the sample can hardly be found in either positive or negative ESI-MS spectra, comparing with FAB-MS. Free from complicating fragments it makes the interpretation of the ESI-MS spectra easy. The detection sensitivity of branch ABS by positive ESI-MS is significantly lower than by negative ESI-MS. CAD spectra of selected ions were used to confirm ESI-MS spectra identification. The content ratio of linear ABS to branched ABS can be determined from negation ion ESI-MS spectrum. Negative ion ESI-MS is a rapid, effective and reliable for the analysis of ABS.%用正、负电喷雾电离( ESI)并结合碰撞活化解离( CAD)质谱法对烷基苯磺酸盐 (ABS)进行鉴定。无论正、负离子化过程中均不出现快原子轰击质谱常见的碎片峰,由于没有复杂碎片峰的干扰, ESI- MS对分析 ABS试样大为有利。正离子 ESI- MS对支化 ABS鉴定的灵敏度远低于负离子 ESI- MS。用 CAD- MS- MS对 ESI- MS谱各主要峰进行了归属。线型与支化 ABS相对含量可以用负离子 ESI- MS求出。负离子化 ESI- MS是快速、有效和可靠的鉴定 ABS的方法。

  17. 鱼吸收富集LAS的分析研究进展%Advances on Uptake and Bioaccumulation of Surfactant Linear Alkylbenzene Sulfonate in Fish

    Institute of Scientific and Technical Information of China (English)

    刘先利; 邓南圣; 刘光红; 薛蓓

    2006-01-01

    LAS对鱼等水生生物均产生有害影响,会破坏鱼鳃上皮组织、影响其相关功能(如通透性等).LAS经由鱼鳃吸收、并通过血液输送到鱼体中各组织.LAS疏水性越大,其在鱼体中生物富集系数越大.水硬度等影响鱼吸收、富集LAS.鱼体中LAS生物转化过程减小了LAS生物富集.鱼体中LAS及其生物转化产物大多是经过固相萃取或基质固相分散萃取后,采用HPLC或HPLC/MS等方法进行分析.

  18. Anaerobic digestion of linear alkyl benzene sulfonates: biodegradation kinetics and metabolite analysis.

    Science.gov (United States)

    García, M T; Campos, E; Ribosa, I; Latorre, A; Sánchez-Leal, J

    2005-09-01

    In the present work the effect of the alkyl chain length and the position of the sulfophenyl substituent of the linear alkylbenzene sulfonates (LAS) on their anaerobic biodegradability have been investigated. Degradation kinetics of the linear alkyl benzene sulfonates homologues, 2phiC10LAS, 2phiC12LAS and 2phiC14LAS, have been studied. It has been also investigated the effect of the isomer type on the degradation rate of the LAS molecule through the comparative study of the 2phiC10LAS and 5phiC10LAS isomers. Batch anaerobic biodegradation tests were performed using sludge from the anaerobic digester of a wastewater treatment plant as microorganisms source. Ultimate biodegradation was evaluated from the biogas production whereas primary biodegradation was determined by specific analysis of the surfactant. LAS homologues and isomers showed a negligible primary biodegradation under anaerobic conditions. Furthermore, analysis of sulfophenyl carboxilates (SPC) by LC-MS indicated a low and constant level of these LAS degradation metabolites over the test period. These data are consistent with a minimal transformation of the LAS parent molecule in the anaerobic digesters. On the other hand, the addition of the shortest alkyl chain length homologues, decyl and dodecylbenzene sulfonates, reduces the biogas production whereas the most hydrophobic homologue, the tetradecylbenzene sulfonate, enhances the biogas production. This LAS homologue seems to increase the availability of organic compounds sorbed on the anaerobic sludge promoting their biodegradation.

  19. Can Early Life-Stages of the Marine Fish Sparus aurata be Useful for the Evaluation of the Toxicity of Linear Alkylbenzene Sulphonates Homologues (LAS C10-C14 and Commercial LAS?

    Directory of Open Access Journals (Sweden)

    M. Hampel

    2002-01-01

    Full Text Available Most commercial household cleaning agents and personal care products contain the anionic surfactant linear alkylbenzene sulphonates (LAS as the active compound. After their use they are discharged, theoretically after adequate wastewater treatment, into receiving waters finally reaching estuaries and coastal waters. Laboratory toxicity tests are useful tools in determining at which concentration a certain wastewater compound becomes hazardous for an existing group of organisms. Early life-stage toxicity tests include exposure during the most sensitive development period of the organism. In fish, this type of assay has shown to predict accurately maximum acceptable toxicant concentration (MATC values (comprised in the range defined by the NOEC and LOEC in fish early life-stage tests. For this reason, larvae of the seabream, Sparus aurata, were exposed to increasing concentrations of LAS homologues (C10-C14 and commercial LAS. Obtained LC50 values ranged between 0.1 and 3.0 mg l-1 and were compared with LC50 values of previous hatching experiments with the same species. Larvae proved to be more sensitive to LAS exposure of individual homologues than eggs, except in the case of commercial LAS. LC50 values can be directly employed to determine their potential risk in a concrete environment with known pollutant concentrations. Dividing the LC50 value with the found homologue concentration and extrapolating with certain security factors proposed by different environmental organisms, potentially hazardous pollutant concentrations may be detected. Average estuarine or coastal LAS concentrations are generally below toxicity limits for this kind of organism, considering that the average alkyl chain length of commercial LAS is 11.6 carbon atoms.

  20. 在线萃取流动注射分光光度法测定消毒食(饮)具烷基苯磺酸钠残留量%Determination of sodium alkylbenzene sulfonate residues in disinfected tableware by on-line extraction FI-spectrophotometry

    Institute of Scientific and Technical Information of China (English)

    郝莉鹏; 闵巍; 李宏亮

    2012-01-01

    目的:建立在线萃取流动注射分光光度法测定食(饮)具烷基苯磺酸钠残留量的方法.方法:100 ml蒸馏水冲洗消毒后食(饮)具制成样液,用在线萃取流动注射分光光度法进行测定.结果:方法检出限1.7 μg/100 cm2,烷基苯磺酸钠的浓度在0 mg/L ~1.00 mg/L有良好的线性(相关系数0.9995),实际样品的加标回收率为92% ~104%,相对标准偏差为3% ~8.5%.结论:本方法操作简便,准确度、精密度好,对操作人员的危害小,适用于消毒食(饮)具中烷基苯磺酸钠残留量的批量检测.%Objective: To establish on - line extraction FI - spectrophotometry for the determination of sodium al-kylbenzene sulfonate residues in disinfected tableware. Methods: The disinfected tableware was rinsed by 100 ml distilled water to obtain the sample solution. Then the sample solution was determined by on - line extraction FI -spectrophotometry. Results: The detection limit was 1. 7 μg/100 cm with linear range of 0 mg/L ~ 1. 00 mg/L ( r = 0.9995). The recoveries were 92% ~ 104% , RSD=3% -8.5%. Conclusion: This method is simple, sensitive, accurate and safe for the determination of sodium alkylbenzene sulfonate residues in disinfected tableware.

  1. Optimization of Biodegradability and Toxicity Testing of Degradation Product from Linear Alkyl BenzeneSulfonate (LAS) Surfactant as Cleaning Detergent Agent

    OpenAIRE

    2009-01-01

    Optimization of Biodegradability and Toxicity Testing of Degradation Product from Linear Alkyl BenzeneSulfonate (LAS) Surfactant as Cleaning Detergent Agent. Linear Alkyl Benzene Sulfonate (LAS) is a surfactantused in laundry detergent as cleaning agent and toxic to aquatic organisms. Results shows, with the LAS concentrationused (20 ppm) in medium, adaptation time and Acinetobacter sp. growth has shown better biodegradation ability thanthree other bacteria used Pseudomonas putida, Pseudomona...

  2. Susceptibility of synthetic long-chain alkylbenzenes to degradation in reducing marine sediments

    Science.gov (United States)

    Eganhouse, Robert P.; Pontolillo, James

    2008-01-01

    Long-chain alkylbenzenes (LCABs) synthesized for production of alkylbenzene sulfonate surfactants have been used as molecular markers of anthropogenic waste for 25 years. Synthetic LCABs comprise two classes, the tetrapropylene-based alkylbenzenes (TABs) and the linear alkylbenzenes (LABs). LABs supplanted TABs in the mid-1960s because of improved biodegradability of their sulfonated analogs. Use of LCABs for molecular stratigraphy depends on their preservation in sediments over decadal time scales. Most laboratory and field studies suggest that LABs degrade rapidly under aerobic conditions but are resistant to degradation when oxygen is absent. However, recent work indicates that LABs may not be as persistent under reducing conditions as previously thought. To assess the potential for degradation of LCABs in reducing sediments, box cores collected in 1992 and 2003 near a submarine wastewater outfall system were analyzed using gas chromatography/mass spectrometry. The TABs were effectively preserved; differences between whole-core inventories were within analytical error. By contrast, whole-core inventories of the LABs decreased by about 50-60% during the same time interval. Based on direct comparison of chemical inventories in coeval core sections, LAB transformation rates are estimated at 0.07 ±. 0.01 yr-1. These results indicate that caution should be exercised when using synthetic LCABs for reconstruction of depositional records.

  3. Alkylbenzene Project in Xinjiang Approved

    Institute of Scientific and Technical Information of China (English)

    Zhou Weiyong

    1996-01-01

    @@ The feasibility study on alkylbenzene project in Dushanzi, Xinjiang Uygur Autonomous Region, submitted jointly by the government of Xinjiang UygurAutonomous Region and China National Petroleum Corporation (CNPC), has been approved by State Council recently,after pass appraisa l by China International Engineering Consulting Corporation entrusted by State Planning Committee.

  4. Terrestrial risk assessment for linear alkyl benzene sulfonate (LAS) in sludge-amended soils.

    Science.gov (United States)

    de Wolf, W; Feijtel, T

    1998-03-01

    A comparison of the estimated environmental concentration and the effect concentrations (in the laboratory or field) in the receiving compartment form the basis of environmental risk assessments. This paper reviews processes that critically influence the fate of LAS in the terrestrial environment. Concentrations of LAS in sludge are quite high due to sorption to primary sludge, precipitation of Ca and Mg-salts of LAS, and lack of biodegradation under anaerobic digestion. This implies that when sludge is applied to soil e.g. as a fertilizer, considerable amounts of this important surfactant may enter the terrestrial environment. Influence of aerobic situations on LAS concentrations during sludge storage needs further research to allow incorporation into the risk assessment. Aerobic biodegradation in soil is considered the most important removal mechanism of LAS loading to the terrestrial environment through sludge-amendment. Sorption plays a role in determining the residence time of a chemical in the soil, hereby enabling more time for biodegradation to occur. In addition, sorption may affect the expression of effects of surfactants towards benthic and soil dwelling organisms and plants. Another factor that needs further attention is the form of LAS in the environment, which is not similar to the commercial material applied in detergents. The differential sorption and biodegradation of the LAS components lead to a shift in the alkyl chain length (homologue), and phenylisomer distribution towards increased hydrophobicity. Also, occurrence of Ca/Mg-salts in the environment versus the Na-salt for the commercial material critically impacts the extrapolation of effects data obtained in lab studies (mostly performed with the commercial material) to the field. The literature data were used in combination with strategies and methods provided by the European Union Technical Guidance Document in support of risk assessment of new and notified substances (1996) for the

  5. NiO/活性炭催化氧化降解水中LAS研究%Study on Degradation of Aqueous Linear Alkylbenzene Sulfonate Using NiO/Activated Carbon

    Institute of Scientific and Technical Information of China (English)

    高建峰; 徐春彦; 白婷婷

    2008-01-01

    以NiO/活性炭为催化剂,并加入H2O2,催化氧化降解100 mL 50 mg/L十二烷基苯磺酸钠(LAS).结果表明,H2O2用量为4.9 mmol/L,温度为50℃,pH值在3~4之间,反应时间为2.0 h,LAS降解率接近80%,COD M去除率为71.6%.

  6. Optimization of Biodegradability and Toxicity Testing of Degradation Product from Linear Alkyl BenzeneSulfonate (LAS Surfactant as Cleaning Detergent Agent

    Directory of Open Access Journals (Sweden)

    Neera Khairani

    2009-11-01

    Full Text Available Optimization of Biodegradability and Toxicity Testing of Degradation Product from Linear Alkyl BenzeneSulfonate (LAS Surfactant as Cleaning Detergent Agent. Linear Alkyl Benzene Sulfonate (LAS is a surfactantused in laundry detergent as cleaning agent and toxic to aquatic organisms. Results shows, with the LAS concentrationused (20 ppm in medium, adaptation time and Acinetobacter sp. growth has shown better biodegradation ability thanthree other bacteria used Pseudomonas putida, Pseudomonas fluorescence, Bacillaria spp. Thus, Acinetobacter sp isused further for biodegradation process of LAS. Based on its biodegradation half-life using Acinetobacter sp, and withmixed culture (± 52.32% and ± 46.82% respectively could be achieved in 4 (four days, LAS could be categorized as abiodegradable compound. The toxicity assay is based on tetrazolium dye reduction with Rhizobium meliloti as indicatororganism. LAS is more toxic than its intermediate product from biodegradation, with IC50 = 34.35 ppm, and theintermediate product, Ac and Cm, has IC50 = 446.19 ppm and 111.28 ppm respectively. Identification of intermediateproducts using IR and LC-MS analysis shows that the degradation product contains chemicals compounds withfunctional group as follows: benzene, benzoic acid, hydroxyl, and aliphatic carbons with large molecule weight. Untilits half-time degradation time, LAS biodegradation process only occurs at the aliphatic carbon chain, and have not yetreached the stage of aromatic ring opening.

  7. Determination of linear alkylbenzene sulfonate in leather by high performance liquid chromatography%高效液相色谱测定皮革中直链烷基苯磺酸盐

    Institute of Scientific and Technical Information of China (English)

    涂红雨; 王俊苏; 陈丽华; 刘浩; 张后兵; 万廷春; 杨静; 王国民

    2015-01-01

    采用高效液相色谱法对皮革中的直链烷基苯磺酸盐(LAS)进行测定.皮革样品采用甲醇超声波提取后浓缩至干,二氯甲烷溶解,经中性氧化铝固相萃取柱净化,浓缩至干,甲醇定容.用反相C8柱(4.6×150 mm,5μm)分离,以甲醇-10 mmol/L乙酸铵为流动相进行等度洗脱,二级管阵列检测器测定波长为225 nm.结果表明,LAS在0.5~ 10.0 mg/L范围内线性关系良好,相关系数大于0.999;检测限为10 mg/kg;在10 ~ 2000 mg/kg添加水平下回收率为86.1%~96.8%,RSD均不大于13%.方法适用于皮革中直链烷基苯磺酸盐的测定.

  8. Determination of linear alkylbenzene sulfonates in auxiliaries by SPE-IPLC-FLD method%SPE-IPLC-FLD法测定助剂中的线性烷基苯磺酸盐

    Institute of Scientific and Technical Information of China (English)

    丁友超; 吴晓琼; 高颖; 汤娟; 蔡建和; 孙成

    2015-01-01

    建立固相萃取-离子对液相色谱-荧光检测器法(SPE-IPLC-FLD),测定纺织染整助剂中的线性烷基苯磺酸盐(LAS).样品经甲醇+水(50+50,体积比)超声助溶、固相萃取SAX柱净化后,以2.5 mmol/L磷酸二氢四丁基铵溶液作为阳离子对试剂、乙腈梯度洗脱,经离子对反应和反相C18柱色谱分离后,得到4组峰(每组包含4个色谱峰)的独特图谱.荧光检测的激发波长为230 nm,发射波长为310 nm.以十二烷基苯磺酸钠为标准物,LAS的定低限为25 mg/kg(S/N=10),线性范围为0.5~250 mg/L,线性关系大于0.999 5,方法的回收率为91.3%~97.4%,批间RSD小于6.8%.对不同类型染整助剂的实际样品检测,LAS检测结果与理论含量比较一致,阳性样品重复测试的RSD都小于4.2%,结果令人满意.

  9. 电动生物修复湖泊底泥中直链烷基苯磺酸钠%Bioremediation of Lake Sediment Contaminated by Linear Alkylbenzene Sulphonates Using Electrokinetic Technology

    Institute of Scientific and Technical Information of China (English)

    刘广容; 叶春松; 钱勤; 张静

    2011-01-01

    Electrodynamic and biological technologies are combined and applied to the remediation of LAS-contaminated lake sediments. A bench scale experiment was conducted with an electrodynamic apparatus and the sediment samples were taken up from East Lake, the largest urban lake in Wuhan, polluted by domestic wastewater containing organic pollutants such as linear alkylbenzene sulphonates(LAS). The experiment started from culture of Bacilli which belong to LAS degrading strains and then electric field was exerted. The coupled electrodynamic bioremediation of the sediment resulted in removal of LAS by 40.5%, a remarked increase compared to biological method singly used. It was found as well that electric field polarity reversal could boost LAS degradation in sediment.%直链烷基苯磺酸钠(Linear Alkylbenzene Sulfonates,LAS)是环境中最常见的具有代表性的一类有机污染物,城市湖泊长期以来接纳了大量的污染物,致使底泥沉积了大最的LAS.采用电动生物复合技术修复东湖底泥中LAS,由于其LAS含量过高,当直接添加芽孢杆菌降解LAS时,发现无明显的降解效果.经过驯化培养芽孢杆菌,得到了降解LAS的菌株.电动生物修复LAS去除率达到40.5%,比单纯的生物修复高出三十多个百分点,比单纯电动修复高出二十个百分点.电极正负极交替有利于底泥中LAS的降解与去除.

  10. Cytotoxic effect of linear alkylbenzene sulfonate on human Chang liver cells%直链烷基苯磺酸钠致人张氏肝细胞损伤的毒性作用

    Institute of Scientific and Technical Information of China (English)

    赵文红; 赵红; 王开磊; 张雯; 王金花

    2016-01-01

    目的 通过检测不同剂量的直链烷基苯磺酸钠(LAS)对人张氏肝细胞(Chang liver cells)增殖、损伤、凋亡及坏死的影响,探讨LAS对人张氏肝细胞的毒性作用.方法 体外培养人张氏肝细胞,将细胞分为对照组及LAS不同剂量组,分别为正常对照组(不合LAS的正常培养基培养细胞)、LAS低、中、高剂量组(37.5、75.0及150.0 mg/L).各组细胞培养24 h后,倒置显微镜下观察细胞形态及结构;四甲基偶氮唑盐(MTT)法检测细胞生存率;检测丙二醛(MDA)、乳酸脱氢酶(LDH)、天门冬氨酸氨基转移酶(AST)水平以了解肝细胞损伤程度;Hoechst 33342及PI染色观察细胞凋亡及坏死情况.结果 LAS处理后细胞表面出现黑色颗粒,部分细胞变圆脱落并产生碎片,高剂量组出现细胞脱落、死亡.LAS各处理组细胞存活率明显低于对照组(P<0.01),MDA、LDH及AST水平也均明显高于对照组;细胞凋亡率与坏死率明显增加(P<0.01),且这些变化随LAS剂量增加更加明显(P<0.01).结论 LAS可抑制人张氏肝细胞增殖,改变细胞形态,并导致细胞损伤、凋亡和坏死.

  11. Effect of linear alkyl benzene sulfonates (LAS) on the fate of phenanthrene in a model ecosystem (water-lava-plant-air)

    Institute of Scientific and Technical Information of China (English)

    JIANG Xia; JIN Xiang-can; YAN Chang-zhou; Ayfer Yediler; OU Zi-qing; Antonius Kettrup

    2004-01-01

    Advanced closed chamber system was used to study the fate of phenanthrene (3-rings PAHs) in the presence of linear alkylbenzene sulphonates(LAS). The results showed mineralization and metabolism of phenanthrene are fast in the "culture solution - lava - plant - air" model ecological system. The distribution proportions of applied 14C-activity in this simulative ecological system were 41%-45%, 14% to 10% and 1% in plant, lava and culture solution respectively, and 18% to 29%, 11% to 8% recovered in the forms of VOCs and CO2. Main parts of the applied 14C-activity exist in two forms, one is polar metabolites(25%) which mainly distribute in the root(23%), the other is unextractable part(23%) which have been constructed into plant root(8.98%), shoot(0.53%) or bonded to lava(13.2%). The main metabolites of phenanthrene were polar compounds(25% of applied 14C-activity), and small portion of 14C-activity was identified as non-polar metabolites(6% of applied 14C-activity) and apparent phenanthrene(1.91% of applied 14C-activity). Phenanthrene and its metabolites can be taken up through plant roots and translocated to plant shoots. The presence of LAS significantly increased the the concentration of 14C-activity in the plant and production of 200 mg/L

  12. A study of anaerobic biodegradation of pure homologue and isomers of linear alkylbenzene sulphonate (LAS) in batch digesters; Estudio de la biodegradacion anaerobia de homologos e isomeros puros de alquibenceno sulfonatos lineales (LAS) en digestores discontinuos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, M. T.; Campos, E.; Illan, P.; Dalman, M.; Sanchez-Leal, J.

    2005-07-01

    In the present work the effect of different structural parameters on the anaerobic degradation of the LAS molecule has been studied. so, the effect both of the alkyl chain length and the phenyl position on the anaerobic degradation of the LAS molecule have been investigated. The behaviour of the individual homologues and isomers was studied applying discontinuous anaerobic tests (ECETOC-28). Sludge from the anaerobic digester of the waste water treatment plant of Manresa (Barcelona) was used as bacterial inoculum source. All the LAS homologues showed a poor primary biodegradation. In addition, no effect of the LAS isomer type was found on the anaerobic degradation kinetics. (Author) 6 refs.

  13. PHYSIOLOGICAL RESPONSES OF THE BROWN MUSSEL Perna perna (MOLLUSCA, BIVALVIA EXPOSED TO THE ANIONIC SURFACTANT LINEAR ALKYLBENZENE SULPHONATE (LAS = RESPOSTAS FISIOLÓGICAS DE MEXILHÃO Perna perna (MOLLUSCA, BIVALVIA EXPOSTO AO SURFACTANTE ANIÔNICO ALQUILBENZENO SULFONATO LINEAR (LAS

    Directory of Open Access Journals (Sweden)

    Marina Freitas Stefanoni

    2011-01-01

    Full Text Available The effects of the Linear Alkylbenzene Sulphonate (LAS were evaluated on the mussel Perna perna, using physiological and genotoxic biomarkers. The Micronuclei (MN assay was used to estimate effects at nuclear level, whereas the physiological effects were evaluated by measuring the oxygen consumption and ammonia excretion rates. Significant effects were observed for the MN assay and the ammonia excretion rate, even in low concentrations. The oxygen consumption was not affected in the tested concentrations. For MN and ammonia excretion, the animals exposed to intermediate concentrations were not affected, but responded to the higher concentrations, indicating the existence of compensatory mechanisms at physiological level. However, parallel to this study other authors indicate the presence of progressive effects at the cellular level, suggesting that the organisms are not capable to recover of such increasing effects. Additionally, the results show that the levels of LAS observed for Brazilian coastal waters may chronically affect the biota. = Os efeitos do Alquilbenzeno Sulfonato de Sódio Linear sobre o mexilhão Perna perna foram avaliados por meio do uso de biomarcadores genotóxicos e fisiológicos. O ensaio da taxa de micronúcleos (MN foi conduzido para estimar o efeito ao nível nuclear, enquanto os efeitos fisiológicos foram avaliados através da medição da taxa de consumo de oxigênio e de excreção de amônia. Efeitos significativos foram observados para o ensaio do MN e para a taxa de excreção de amônia, mesmo em baixas concentrações. O consumo do oxigênio não foi afetado pelas concentrações dos ensaios. Para MN e excreção de amônia, os animais expostos às concentrações intermediárias não foram afetados, mas responderam às maiores concentrações, sugerindo a existência de mecanismos compensatórios em nível fisiológico. Contudo, paralelamente ao presente estudo, outros autores demonstraram haver efeitos

  14. Las degradation in a fluidized bed reactor and phylogenetic characterization of the biofilm

    Directory of Open Access Journals (Sweden)

    L. L. Oliveira

    2013-09-01

    Full Text Available A fluidized bed reactor was used to study the degradation of the surfactant linear alkylbenzene sulfonate (LAS. The reactor was inoculated with anaerobic sludge and was fed with a synthetic substrate supplemented with LAS in increasing concentrations (8.2 to 45.8 mg l-1. The removal efficiency of 93% was obtained after 270 days of operation. Subsequently, 16S rRNA gene sequencing and phylogenetic analysis of the sample at the last stage of the reactor operation recovered 105 clones belonging to the domain Bacteria. These clones represented a variety of phyla with significant homology to Bacteroidetes (40%, Proteobacteria (42%, Verrucomicrobia (4%, Acidobacteria (3%, Firmicutes (2%, and Gemmatimonadetes (1%. A small fraction of the clones (8% was not related to any phylum. Such phyla variety indicated the role of microbial consortia in degrading the surfactant LAS.

  15. Enantioselective degradation and unidirectional chiral inversion of 2-phenylbutyric acid, an intermediate from linear alkylbenzene, by Xanthobacter flavus PA1

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yishan; Han, Ping [School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong (China); Li, Xiao-yan; Shih, Kaimin [Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (China); Gu, Ji-Dong, E-mail: jdgu@hkucc.hku.hk [School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong (China); The Swire Institute of Marine Science, The University of Hong Kong, Shek O, Cape d' Aguilar, Hong Kong (China)

    2011-09-15

    Highlights: {yields} We isolated a Xanthobacter flavus strain PA1 utilizing the racemic 2-PBA and the single enantiomers as the sole source of carbon and energy. {yields} Both (R) and (S) forms of enantiomers can be degraded in a sequential manner in which the (S) disappeared before the (R) form. {yields} The biochemical degradation pathway involves an initial oxidation of the alkyl side chain before aromatic ring cleavage. - Abstract: Microbial degradation of the chiral 2-phenylbutyric acid (2-PBA), a metabolite of surfactant linear alkylbenzene sulfonates (LAS), was investigated using both racemic and enantiomer-pure compounds together with quantitative stereoselective analyses. A pure culture of bacteria, identified as Xanthobacter flavus strain PA1 isolated from the mangrove sediment of Hong Kong Mai Po Nature Reserve, was able to utilize the racemic 2-PBA as well as the single enantiomers as the sole source of carbon and energy. In the presence of the racemic compounds, X. flavus PA1 degraded both (R) and (S) forms of enantiomers to completion in a sequential manner in which the (S) enantiomer disappeared much faster than the (R) enantiomer. When the single pure enantiomer was supplied as the sole substrate, a unidirectional chiral inversion involving (S) enantiomer to (R) enantiomer was evident. No major difference was observed in the degradation intermediates with either of the individual enantiomers when used as the growth substrate. Two major degradation intermediates were detected and identified as 3-hydroxy-2-phenylbutanoic acid and 4-methyl-3-phenyloxetan-2-one, using a combination of liquid chromatography-mass spectrometry (LC-MS), and {sup 1}H and {sup 13}C nuclear magnetic resonance (NMR) spectroscopy. The biochemical degradation pathway follows an initial oxidation of the alkyl side chain before aromatic ring cleavage. This study reveals new evidence for enantiomeric inversion catalyzed by pure culture of environmental bacteria and emphasizes the

  16. Responses and toxin bioaccumulation in duckweed (Lemna minor) under microcystin-LR, linear alkybenzene sulfonate and their joint stress.

    Science.gov (United States)

    Wang, Zhi; Xiao, Bangding; Song, Lirong; Wang, Chunbo; Zhang, Junqian

    2012-08-30

    Microcystin-LR (MCLR) and linear alkylbenzene sulfonate (LAS) are commonly found in eutrophic lakes due to toxic cyanobacterial blooms and exogenous organic compounds pollution. However, the ecotoxicological risk of their combination in the aquatic environment is unknown. This study investigated the effects of MCLR, LAS and their mixture on duckweed (Lemna minor) growth and physiological responses. MCLR accumulation in duckweed, with or without LAS, was also examined. Growth of duckweed and chlorophyll-a contents were significantly reduced after 8d exposure to high concentrations of MCLR (≥ 3 μg/ml), LAS (≥ 20 μg/ml) and their mixture (≥ 3+10 μg/ml). After 2d of exposure, superoxide dismutase activity and glutathione content in duckweed increased with increasing concentrations of MCLR, LAS and their mixture, with a significant difference observable after 8d of exposure. When MCLR and LAS concentrations were lower (≤ 0.1+1 μg/ml), the interaction of them is synergistic, but when the concentrations were higher, the synergy was weak. MC accumulation was much higher at 2d than at 8d when duckweed was exposed to lower concentrations of MCLR (≤ 3 μg/ml) or MCLR-LAS (≤ 3+10 μg/ml). Furthermore, LAS significantly enhanced the accumulation of MCLR in duckweed, even with LAS concentrations as low as 0.3 μg/ml (environmental concentration), indicating that greater negative ecological risks and higher MCLR phytoremediation potentials of duckweed might occur in MCLR-LAS-concomitant water.

  17. Risk assessment of linear alkylbenzene sulphonates, LAS, in agricultural soil revisited: Robust chronic toxicity tests for Folsomia candida (Collembola), Aporrectodea caliginosa (Oligochaeta) and Enchytraeus crypticus (Enchytraeidae)

    DEFF Research Database (Denmark)

    Krogh, P. H.; Lopez, C. V.; Cassani, G.;

    2007-01-01

    was not affected by concentrations up to 120 mg LAS kg-1 soil. When adding (low contaminated) non-spiked sludge to soil, high stimulation of reproduction was ob-served for E. crypticus and A. caliginosa but not for F. candida. We argue that this difference in stimulative response between the tested species...... is related to the difference in feeding behaviour. Sludge spiked with LAS did not significantly affect the reproduction of F. candida (fertility: num-ber of juvenile offspring) and A. caliginosa (fecundity: number of cocoons) (dose equivalent to 181 g and 91 g LAS kg¬-1 sludge respectively). Significantly...

  18. Effect of Dermal Exposure to Paraphenylenediamine and Linear Alkylbenzene Sulphonate in Guinea Pigs

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Objective To study the effects of paraphenylenediamine (PPD) and linear alkylbenzene sulphonate (LAS) alone and in combination on the skin. Methods Forty-eight guinea pigs were divided equally into 4 groups and exposed to PPD (4 mg/kg), LAS (12 mg/kg) and PPD (4 mg/kg) plus LAS (12 mg/kg) for 30 days. The biochemical parameters such as acid phosphatase, gtutathione-s-transferase, glutathione peroxidase, glutathione, lipid peroxidation and histamine contents in exposed skin were estimated. The histopathological examination of the exposed skin was also carried out. Results The skin enzymes, lipid peroxidation, and histamine increased while glutathione decreased in skin. The simultaneously exposed group showed additive toxic effects. The histopathological examination showed severe hyperkeratosis, thickening of collagen fibres and vacuolisation of epidermal cells in PPD plus LAS exposed skin. Conclusion The findings of the present study suggest that simultaneous exposure to PPD and LAS has additive toxic effects.

  19. INHIBITION OF ALKYLBENZENE BIODEGRADATION UNDER DENITRIFYING CONDITIONS BY USING THE ACETYLENE BLOCK TECHNIQUE

    Science.gov (United States)

    Addition of acetylene to microcosms simultaneously amended with nitrate and alkylbenzenes resulted in inhibition of the rate of alkylbenzene biodegradation under denitrifying conditions. Toluene, xylenes, and 1,2,4-trimethylbenzene were recalcitrant, whereas ethylbenzene was degr...

  20. STUDY OF ISOLATION, IDENTIFICATION AND CHARACTERIZATION OF TWO STRAINS FOR CO-METABOLIC BIODEGRADATION OF LINEAR ALKYLBENZENE SULFONATE%两株直链烷基苯磺酸钠共代谢降解菌株的分离、鉴定和降解特性研究

    Institute of Scientific and Technical Information of China (English)

    周利; 季瑞武; 朱佳; 冉治霖; 高静思

    2016-01-01

    自深圳某污水处理厂曝气池和二沉池的污泥中分离得到2株通过共代谢机制降解直链烷基苯磺酸钠(LAS)的细菌L-2和L-15.通过生理生化和16S rRNA基因序列分析,初步鉴定细菌L-2和L-15分别为Klebsiella sp.和Enterobacter sp..研究表明:L-2和L-15以LAS作为唯一碳源时,对其降解率仅有1.1%和5.9%.当添加葡萄糖作生长基质,L-2在温度30℃,pH =7.5,m(葡萄糖)∶m(LAS)为20∶1的条件下,对50 mg/L的LAS的降解率可达94.2%;L-15在温度30℃,pH =7.5,m(葡萄糖)∶m(LAS)为16∶1的条件下,对50 mg/L的LAS的降解率可达92.2%.试验结果说明,筛选得到的2株细菌在共代谢的作用下,可以有效地实现废水中LAS降解.

  1. Linear alkylbenzenes in urban riverine environments in Tokyo: distribution, source, and behavior

    Energy Technology Data Exchange (ETDEWEB)

    Takada, H.; Ishiwatari, R.

    1987-09-01

    The distribution of linear alkylbenzenes (LABs) and linear alkylbenzenesulfonates (LASs) in river sediments, suspended river particles, domestic wastes, and waste effluents around the Tokyo city area was investigated. LABs as well as LASs with alkyl carbon chain lengths in the range from 10 to 14 were found in all environmental samples and LAS-type synthetic detergents examined. These results indicate that LABs are carried into aquatic environments as a result of the use of synthetic detergents around the Tokyo metropolitan area. Further results are (1) LABs in urban river sediments originate predominantly from untreated domestic wastes, final effluents contributing only a minor portion of the LABs in sediments, (2) the isomeric composition of the LABs changes systematically during biodegradation, and (3) the ratio of LAS to LAB decreases as follows: commercial synthetic detergents > suspended particles in domestic wastes > river sediments > Tokyo Bay sediments.

  2. Study on the Adsorption Ability to Linear Alkylbenzene Sulfonate of Zeolite P Modified by Cetrimonium Bromide in Waste Water%十六烷基三甲基溴化铵修饰P型沸石吸附水中直链烷基苯磺酸钠的研究

    Institute of Scientific and Technical Information of China (English)

    谭文渊; 徐曼; 曾英

    2016-01-01

    通过使用碱液对天然斜发沸石(Z)进行处理制得P型沸石(PZ),再用十六烷基三甲基溴化铵(CTMAB)对Z和PZ进行修饰,制得有机改性沸石ZC和PZC,对比考察了ZC和PZC对直链烷基苯磺酸钠(LAS)的吸附性能.实验结果表明,制得的PZ硅/铝比为2,比Z(4.85)降低58.8%;PZ的零净电荷点、比表面积、孔径和孔容均高于Z;吸附平衡时间为4h.当pH=2时,ZC和PZC对LAS吸附量达到最高,吸附数据符合Langmuir准二级动力学方程和Langmuir等温吸附方程,饱和吸附量(qm)分别为12.658和27.100mg/g,吸附过程主要为单分子层的化学吸附,PZC的吸附速率常数大于ZC,具有更好的动力学性能.

  3. SiW12/NaY固体杂多酸催化剂的微波合成及LAS降解性能研究%Studies on Synthesis of Silicotungstic Acid Supported on NaY Zeolite Catalysts by Microwave Radiation and Their Degradation Properties for Linear Alkylbenzene Sulfonates

    Institute of Scientific and Technical Information of China (English)

    赵景联; 赵靓; 苏慈; 李厚宝

    2006-01-01

    以微波辐射方法合成了NaY分子筛、二氧化锆和二氧化钛不同载体负载磷钨酸、磷钼酸、硅钨酸不同杂多酸的固体酸催化剂,用Hammett指示剂与紫外光谱相结合的方法测定固体杂多酸催化剂的酸度,发现SiW12/NaY酸性最强.单因子实验研究了制备条件对SiW12/NaY固体酸催化剂酸活性的影响,正交试验探讨了影响SiW12/NaY固载杂多酸活性四个因素的大小顺序为:烧结时间>烧结功率>浸泡浓度>浸泡时间,催化剂制备的优化条件为:硅钨酸水溶液浓度0.10 mol/L,浸泡时间30 h,微波功率750 W,烧结时间40min,制得的催化剂酸度最高.应用0.050 g SiW12/NaY固载硅钨酸催化剂降解150 mg/L,pH值为3的十二烷基苯磺酸钠(LAS)溶液60min,LAS降解率由76%提高到94.5%.固载硅钨酸催化剂对LAS的降解率明显提高.

  4. Toxicity Test of Linear Alkyl Benzene Sulfonate (LAS)on Several Algal Species%十二烷基苯磺酸钠对于几种藻类的毒性试验

    Institute of Scientific and Technical Information of China (English)

    汤琳; 袁峻峰; 陈德辉

    2000-01-01

    运用评价化学品对藻类毒性的标准试验法,研究了十二烷基苯磺酸钠(Linear Alkyl Benzene Sulfonate)(缩写LAS)对四种藻类的急性毒性,斜生栅藻(Scenedesmus obiliauus)、粉核小球藻(Chlorella pyrenoidosa)、羊角月牙藻(Selenastrum capricornutum)和水华鱼腥藻(Anabaena flos-aquae),它们的96 h EbC50分别是:129.17mg/L,39.79mg/L,149.53mg/L,12.92mg/L.试验结果表明,LAS对于这4种藻类都有明显的抑制作用,不同藻类对于LAS的毒性作用的敏感性不同.与3种绿藻相比,水华鱼腥藻对于LAS的毒性最为敏感.

  5. Comparative toxicity of some detergents on an estuarine fish, Ambassis commersonii

    OpenAIRE

    1988-01-01

    The comparative toxicity was evaluated using four detergents, viz, linear alkylbenzene sulfonate (LAS), branched alkylbenzene sulfonate (BAS), sodium sulfonate (SS) and alfa-olefin sulfonate (AOS) on an estuarine fish, Ambassis commersonii, abundant in Kali estuarine system. Standard toxicity bioassay method was followed as per APHA (1980). AOS concentration in "Mega" soap was determined by the standard MBAS method described in APHA (1980). The results indicate that LAS was the most toxic det...

  6. Simulation of Suspension Catalytic Distillation for Synthesis of Linear Alkylbenzene

    Institute of Scientific and Technical Information of China (English)

    王二强; 李成岳

    2003-01-01

    Suspension catalytic distillation (SCD) has been developed recently as an innovative technology in catalytic distillation. In this paper, a brief introduction to SCD is given and an equilibrium stage (EQ) model is developed to simulate this new process for synthesis of linear alkylbenzene (LAB) from benzene and 1-dodecene.Since non-ideality of this reaction system is not strong, EQ model developed could be applied to it successfully.Simulation results agree well with experimental data, and indicate some characteristics of SCD process as an advanced technology for the production of LAB: 100% conversion of olefins, low temperature (90-100℃) and low benzene/olefin mole ratio.

  7. Sulfonated Polyetherimide and Its Membranes

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Polyetherimide (PEI) was sulfonated by chlorosulfonic acid for the first time. The sulfonated products were characterized by FT-IR, DSC, ion exchange capacity and water sorption measurement. The hydrophilicity of PEI was improved by the sulfonation. The PEI was blended with the sodium salt form of sulfonated PEI (SPEI) to prepare microporous membranes. The morphologies of the membranes were studied with Scanning Electron Microscope (SEM).

  8. Analytical methodology for sulfonated lignins

    NARCIS (Netherlands)

    Brudin, S.; Schoenmakers, P.

    2010-01-01

    There is a significant need to characterize and classify lignins and sulfonated lignins. Lignins have so far received a good deal of attention, whereas this is not true for sulfonated lignins. There is a clear demand for a better understanding of sulfonated lignins on a chemical as well as physical

  9. Environmental Biotechnology: Moving from the Flask to the Field

    Science.gov (United States)

    1991-09-30

    Procter and Gamble Co., Ivorydale Technical Center A pond receiving high levels of linear alkylbenzene sulfonate (LAS) and a pristine pond were compared... Linear Alkylbenzene Sulfonates by a Mixed Bacterial Culture Luis Jimenez, Ph.D., Alec Breen, Gary S. Sayler, Ph.D., The Center for Environmental...and Catabolic Gene Frequencies in Linear Alkylbenzene Contaminated and Pristine Freshwater Ponds Alec Breen, Luis Jimenez, Ph.D., and Gary S.Sayler

  10. Environmental behavior and effect of anionic surfactant (LAS)%阴离子表面活性剂(LAS)环境行为与环境效应

    Institute of Scientific and Technical Information of China (English)

    郭伟; 李培军

    2004-01-01

    由于直链烷基苯磺酸盐(Linear Alkylbenzene Sulfonates,LAS)的广泛运用,LAS成为环境中最常见的具有代表性的一类有机污染物,其环境行为与环境效应也受到普遍的关注.尽管许多研究表明,目前的LAS使用水平对大多数生物来说是安全的,但也有研究表明LAS在低浓度条件下对鱼类产生慢性毒性.同时LAS对生物的伤害机理也不十分清楚,因此LAS的伤害机理和毒性效应的临界值尚需进一步探讨.LAS在不同环境中的吸附、沉降和生物降解等迁移转化行为十分复杂,但对于其在环境中的吸附机制和影响因素尚难以得到一致结论,而对于生物降解过程中的中间代谢产物的成分、行为和毒性也需进一步深入研究.

  11. Synthesis of dodecyl lauroyl benzene sulfonate and its application in enhanced oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Zhenggang; Wu, Le; Sun, Mingming; Jiang, Jian-zhong; Wang, Feng [Jiangnan Univ., Wuxi (China). School of Chemical and Material Engineering

    2011-09-15

    A new hydrophobic surfactant, dodecyl lauroyl benzene sulfonate (DLBS), was synthesized and its application in enhanced oil recovery by alkali-surfactant-polymer (ASP) flooding was studied. The results show that DLBS can be synthesized by reaction of industrial dodecyl benzene with lauroyl chloride in the presence of AlCl{sub 3}, followed by sulfonation with ClSO{sub 3}H and neutralization with NaOH. The lauroyl-group is confirmed to be connected to the para-position of the alkylbenzene by1HNMR spectrum. The synthesized DLBS is well soluble in pure water and reservoir (connate) water at 45 C. It is highly surface active which is indicated by its low CMC of 1.1 . 10{sup -5} mol/L, and its low surface tension, {gamma}{sub cmc} of 28.6 mN m{sup -1}. By mixing with heavy alkylbenzene sulfonates of relatively low average molar mass (387g mol{sup -1}) at a total surfactant concentration of 5 mM, DLBS can reduce the interfacial tension of Daqing crude oil/connate water to an order of 10{sup -3} mN/m at 45 C in the presence of 0.5-1.0 wt.% NaOH and 1000 mg L{sup -1} of polymer. If the NaOH was replaced by a gentle alkaline salt, Na{sub 2}CO{sub 3}, certain amounts of dodecyl dimethyl carboxy betaine were added and the concentration of Na{sub 2}CO{sub 3} was increased to 1.2-2.0 wt.%, the interfacial tension of Daqing crude oil/connate water can also be reduced to an ultralow value. Therefore DLBS is a good hydrophobic surfactant applicable in ASP flooding with either NaOH or Na{sub 2}CO{sub 3} as alkaline agents. (orig.)

  12. UV/Fenton联合生物接触氧化工艺去除废水中LAS应用研究%Application Research of LAS in Wastewater Removal of UV/Fenton Combined with Biological Contact Oxidation Process

    Institute of Scientific and Technical Information of China (English)

    徐晓毅

    2015-01-01

    针对直链烷基苯磺酸钠(LAS)的降解机理,选择UV/Fenton法联合接触生物氧化法处理LAS高盐废水,结果显示:UV/Fenton工艺降解效果明显优于Fenton工艺,对于含LAS污染物存在一个H2O2和FeSO4最佳投加量,采取H2O2分批投加的方式确实能够提高处理效果.%In view of linear alkylbenzene sulfonate (LAS)degradation mechanism,the UV/Fenton method combined with biological contact oxidation process were selected to treat LAS wastewater with high salinity.The results showed that the UV/Fenton process degradation effect was obviously better than that of the Fenton process. LAS pollutants had the best dosage of H2O2 and FeSO4.The UV/Fenton process with H2O2 batch addition way could improve treatment effects.

  13. Asymmetric energy flow in liquid alkylbenzenes: A computational study

    Energy Technology Data Exchange (ETDEWEB)

    Leitner, David M., E-mail: dml@unr.edu [Department of Chemistry and Chemical Physics Program, University of Nevada, Reno, Nevada 89557 (United States); Freiburg Institute for Advanced Studies (FRIAS), Freiburg (Germany); Pandey, Hari Datt [Department of Chemistry and Chemical Physics Program, University of Nevada, Reno, Nevada 89557 (United States)

    2015-10-14

    Ultrafast IR-Raman experiments on substituted benzenes [B. C. Pein et al., J. Phys. Chem. B 117, 10898–10904 (2013)] reveal that energy can flow more efficiently in one direction along a molecule than in others. We carry out a computational study of energy flow in the three alkyl benzenes, toluene, isopropylbenzene, and t-butylbenzene, studied in these experiments, and find an asymmetry in the flow of vibrational energy between the two chemical groups of the molecule due to quantum mechanical vibrational relaxation bottlenecks, which give rise to a preferred direction of energy flow. We compare energy flow computed for all modes of the three alkylbenzenes over the relaxation time into the liquid with energy flow through the subset of modes monitored in the time-resolved Raman experiments and find qualitatively similar results when using the subset compared to all the modes.

  14. Development and application of environmental friendly experimental sulfonation apparatus%环保型实验磺化装置的开发及应用

    Institute of Scientific and Technical Information of China (English)

    张广良; 杨效益; 郭朝华

    2011-01-01

    An environmental friendly experimental sulfonation apparatus was developed with liquid sulfur trioxide as raw material. This apparatus was used to sulfate linear alkylbenzene and alpha-olefin, and the neutralization value, colour, the content of active matter and unsulfated matter of products were determined by national standard, and the results were compared with physical-chemical indexes of nation standard industrial linear alkylbenzene sulfonic acid (GB/T 8447-2008) and sodium alpha-olefin sulfonate (GB/T 20200-2006 ), respectively. The results show that all indexes achieve the national standard except for the colour of alpha-olefin sulfonate, thus it is proved that this apparatus can be successfully used to synthesize new products and improve sulfonation process.%开发了以液体SO3为原料的环保型实验磺化装置,应用该装置对直链烷基苯和α-烯烃进行磺化,采用国标方法对磺化产物的中和值、色泽、有效物及未磺化物含量进行测定,并将测定结果分别与工业直链烷基苯磺酸( GB/T 8447-2008)和α-烯基磺酸钠( GB/T 20200-2006)产品的理化指标相比较,结果表明,除α-烯基磺酸钠产品色泽值略高外,其他各项指标均达到相应的国标要求,从而证明了该装置在合成磺化产品以及改进磺化工艺中的可行件.

  15. Measurements of the densities, isobaric thermal expansion coefficients and isothermal compressibilities of linear alkylbenzene in large liquid scintillator detectors

    CERN Document Server

    Zhou, Xiang; Liu, Qian; Zhang, Zhenyu; Ding, Yayun; Zhou, Li; Cao, Jun

    2014-01-01

    We report the measurements of the densities of linear alkylbenzene at three temperatures over 4 to 23 Celsius degree with pressures up to 10 MPa. The measurements have been analysed to yield the isobaric thermal expansion coefficients and, so far for the first time, isothermal compressibilities of linear alkylbenzene.

  16. PHOTOPHYSICAL STUDY OF SULFONATED POLYSTYRENE

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jixiang; LI Hexian; WANG Guochang; WANG Yuexi; HE Binglin

    2004-01-01

    The photophysical properties of a series of sulfonated micromolecule (paratoluenesulfonic acid, HPTS) and macromolecules (linear and crosslinked polystyrene) have been studied by steady-state fluorescence spectra. The results indicate that the ground sulfonated ring associations can form in both the micromolecules and the macromolecules. The fluorescence spectra of the sulfonated crosslinked copolymers appear a red-shift when the copolymers change from hydrogen-type to sodium-type, and some new emission bands appear in the long-wavelength region. These results are explained in terms of synergetic effect of hydrogen bond, π-π interaction and crosslinking effect.

  17. New rapid methods for determination of total LAS in sewage sludge by high performance liquid chromatography (HPLC) and capillary electrophoresis (CE)

    Energy Technology Data Exchange (ETDEWEB)

    Villar, M. [Department of Analytical Chemistry, Faculty of Chemistry, University of Seville, c/Profesor Garcia Gonzalez s/n, 41012 Seville (Spain); Callejon, M. [Department of Analytical Chemistry, Faculty of Chemistry, University of Seville, c/Profesor Garcia Gonzalez s/n, 41012 Seville (Spain)], E-mail: mochon@us.es; Jimenez, J.C.; Alonso, E.; Guiraum, A. [Department of Analytical Chemistry, Faculty of Chemistry, University of Seville, c/Profesor Garcia Gonzalez s/n, 41012 Seville (Spain)

    2009-02-23

    Linear alkylbenzene sulfonates (LAS) are the most common synthetic anionic surfactant used in domestic and industrial detergents, with a global production of 2.4 x 10{sup 6} t year{sup -1}. After use and disposal, LAS may enter the environment by one of the several routes, including by direct discharge to surface water or discharge to water from sewage treatment plants. Sewage treatment plants break down LAS only partly: some of them remain in effluent and other fraction is adsorbed in sewage solid. New and rapid methods for determination of total LAS from sewage sludge based on microwave assisted extraction and HPLC-FL and CE-DAD determination are proposed. The extraction of total LAS is carried out by using microwaves energy, an extraction time of 10 min and 5 mL of methanol. For HPLC-FL determination, mobile phase acetonitrile-water was used, comprising 60% (v/v) from 0 to 1 min and a flow rate of 1 mL min{sup -1} programmed to 100% acetonitrile between 1 and 2 min and a flow rate of 2 mL min{sup -1}. The final composition was maintained for a further 5 min. The determination of total LAS by CE-DAD was performed in a phosphate buffer (10 mM, pH 9). The separation voltage was 25 kV and the temperature of the capillary was 30 deg. C. Injections were performed in the pressure mode and the injection time was set at 12 s. The determination of total LAS is carried out in less than 5 min. The methods did not require clean-up or preconcentration steps. Detection limit for total LAS in the sludge was 3.03 mg kg{sup -1} using HPLC-FL and 21.0 mg kg{sup -1} using CE-DAD, and recoveries were >85% using both determination methods. Concentrations of total LAS obtained using both methods were compared with the sum of concentrations of homologues LAS C-10, LAS C-11, LAS C-12 and LAS C-13 obtained using microwaves assisted extraction and HPLC-FL and CE-DAD determination.

  18. Photosynthesis tests as an alternative to growth tests for hazard assessment of toxicant

    DEFF Research Database (Denmark)

    Petersen, S.; Kusk, Kresten Ole

    2000-01-01

    Acute (3- and 6-h) toxic responses toward Cu, linear alkylbenzene sulfonate (LAS), and tributyltin (TBT) of lightsaturated and unsaturated photosynthesis were investigated for Rhodomonas salina and Skeletonema costatum obtained from exponentially growing batch cultures and from chemostat cultures...

  19. Effect of linear alkyl benzene sulfonate in skin of fish fingerlings (Cirrhina mrigala): observations with scanning electron microscope.

    Science.gov (United States)

    Misra, V; Chawla, G; Kumar, V; Lal, H; Viswanathan, P N

    1987-04-01

    Pathomorphological changes in the skin was noticed under the scanning electron microscope in fish fingerlings (Cirrhina mrigala) exposed to 0.005 ppm (25% of the LC50) concentration to linear alkyl benzene sulfonate. The epithelial cells present in the epidermis of the skin were found to secrete more mucus with linear alkyl benzene sulfonate (LAS) than did controls. The presence or deposition of mucus on the surface of skin indicated likely molecular interaction between constituents of mucus and LAS.

  20. Coarse graining of polystyrene sulfonate

    Science.gov (United States)

    Perahia, Dvora; Agrawal, Anupriya; Grest, Gary S.

    2015-03-01

    Capturing large length scales in soft matter while retaining atomistic properties is imperative to computational studies. Here we develop a new coarse-grained model for polystyrene sulfonate (PSS) that often serves as a model system because of its narrow molecular weight distribution and defined degree of sulfonation. Four beads are used to represent polymer where the backbone, the phenyl group, and the sulfonated group are each represented by a different bead and the fourth one represents counterion, which is sodium in our case. Initial atomistic simulations of PSS melt with sulfonation levels of 2-10%, with a dielectric constant ɛ = 1 revealed a ``locked'' phase where motion of the polymer is limited. Dielectric constant of ɛ = 5 was used to accelerate the dynamics. Bonded interactions were obtained using Boltzmann inversion on the bonded distributions extracted from atomistic simulation. Non-bonded interaction of polystyrene monomer was taken from our previous work and potential of mean force was used as the initial guess for interaction of the ionic beads. This set of potential was subsequently iterated to get a good match with radial distribution functions. This potential and its transferability across dielectric constants and temperatures will be presented. Grant DE-SC007908.

  1. 影响LAS吸附和生物降解的环境因素分析%Analysis of Affecting Factors of Sorption and Biodegradation of LAS in The Environment

    Institute of Scientific and Technical Information of China (English)

    汤奕昕; 寿森炎

    2008-01-01

    由于直链烷基苯磺酸钠(Linear Alkylbenzene Sulfonates,LAS)在纺织、化工等行业中的广泛运用,LAS成为环境中最常见的具有代表性的一类有机污染物,其吸附、降解等环境行为受到普遍的关注.现结合近几年对LAS的试验研究成果,对影响LAS在环境中的吸附、降解行为的因素,包括土壤类型、温度、初始浓度、微生物活性等做了初步总结.由于LAS在不同环境中的吸附、生物降解等行为十分复杂,对于其在环境中的吸附机制和一些土壤影响因素尚难以得到一致结论,需进一步深入研究.

  2. Optimization based on retention prediction and information theory for liquid-chromatographic analysis of alkylbenzenes

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, Rieko; Hayashi Yuzuru; Suzuki Takashi; Saito Yukio (National Inst. of Hygienic Sciences, Tokyo (Japan)); Jinno Kiyokatsu (Toyohashi Univ. of Technology (Japan))

    1991-11-01

    The mobile phase composition and column length are optimized for analyses of six alkylbenzenes in reversed-phase liquid chromatography with the aid of retention prediction and information theory. Optimal conditions selected according to the resolution Rs and information theory are evaluated from the viewpoint of the precision and analytical efficiency (rapidity) of chromatography. The combination of the information-theoretical optimization with the retention prediction will accelerate the development in the automation of liquid-chromatographic analysis.

  3. Synthesis and characterization of sulfonated cardo poly(arylene ether sulfone)s for fuel cell proton exchange membrane application

    Energy Technology Data Exchange (ETDEWEB)

    Islam, M.M.; Jang, H.H.; Lim, Y.D.; Seo, D.W.; Kim, W.G. [Department of Applied Chemistry, Konkuk University, Chungju, Chungbuk (Korea, Republic of); Kim, T.H.; Hong, Y.T. [Energy Material Research Center, Korea Research Institute of Chemical Technology, Daejeon (Korea, Republic of); Kim, D.M. [Material Engineering and Science, Hongik Univ, Jochiwon-eup, Yeongi-gun, Chungnam (Korea, Republic of)

    2012-12-15

    Sulfonated cardo poly(arylene ether sulfone)s (SPPA-PES) with various degrees of sulfonation (DS) were prepared by post-sulfonation of synthesized phenolphthalein anilide (PPA; N-phenyl-3,3'-bis(4-hydroxyphenyl)-1-isobenzopyrolidone) poly(arylene ether sulfone)s (PPA-PES) by using concentrated sulfuric acid. PPA-PES copolymers were synthesized by direct polycondensation of PPA with bis-(4-fluorophenyl)-sulfone and 4,4'-sulfonyldiphenol. The DS was varied with different mole ratios of PPA (24, 30, 40, 50 mol.%) in the polymer. The structure of the resulting SPPA-PES copolymers and the different contents of the sulfonated unit were studied by Fourier transform infrared (FT-IR) spectroscopy, {sup 1}H NMR spectroscopy, and thermogravimetric analysis (TGA). Sorption experiments were conducted to observe the interaction of sulfonated polymer with water. The ion exchange capacity (IEC) and proton conductivity of SPPA-PES were evaluated according to the increase of DS. The water uptake (WU) of the resulting SPPA-PES membranes was in the range of 20-72%, compared with 28% for Nafion 211 registered. The SPPA-PES membranes showed proton conductivities of 23-82 mS cm{sup -1}, compared with 194 mS cm{sup -1} for Nafion 211 registered, under 100% relative humidity (RH) at 80 C. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  4. Preparation and characterization of sulfonated amine-poly(ether sulfone)s for proton exchange membrane fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Dong-Wan; Lim, Young-Don; Lee, Soon-Ho; Jeong, Young-Gi; Kim, Whan-Gi [Department of Applied Chemistry/RIC-ReSEM, Konkuk University, Chungju-si, Chungbuk 380-701 (Korea, Republic of); Hong, Tae-Whan [Department of Materials Sci and Engineering/RIC-ReSEM, Chungju National University, Chungju, Chungbuk (Korea, Republic of)

    2010-12-15

    Sulfonated amine-poly(ether sulfone)s (S-APES)s were prepared by nitration, reduction and sulfonation of poly(ether sulfone) (ultrason {sup registered} -S6010). Poly(ether sulfone) was reacted with ammonium nitrate and trifluoroacetic anhydride to produce the nitrated poly(ether sulfone), and was followed by reduction using tin(II)chloride and sodium iodide as reducing agents to give the amino-poly(ether sulfone). The S-APES was obtained by reaction of 1,3-propanesultone and the amino-poly(ether sulfone) (NH{sub 2}-PES) with sodium methoxide. The different degrees of nitration and reduction of poly(ether sulfone) were successfully synthesized by an optimized process. The reduction of nitro group to amino was done quantitatively, and this controlled the contents of the sulfonic acid group. The films were converted from salt to acid forms with dilute hydrochloric acid. Different contents of sulfonated unit of the S-APES were studied by FT-IR, {sup 1}H NMR spectroscopy, differential scanning calorimetry (DSC), and thermo gravimetric analysis (TGA). Sorption experiments were conducted to observe the interaction of sulfonated polymers with water and methanol. The ion exchange capacity (IEC), a measure of proton conductivity, was evaluated. The S-APES membranes exhibit conductivities (25 C) from 1.05 x 10{sup -3} to 4.83 x 10{sup -3} S/cm, water swell from 30.25 to 66.50%, IEC from 0.38 to 0.82 meq/g, and methanol diffusion coefficients from 3.10 x 10{sup -7} to 4.82 x 10{sup -7} cm{sup 2}/S at 25 C. (author)

  5. A Durable Alternative for Proton-Exchange Membranes: Sulfonated Poly(Benzoxazole Thioether Sulfone)s

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Dan; Li, Jin Hui; Song, Min Kyu; Yi, Baolian; Zhang, Huamin; Liu, Meilin

    2011-02-24

    To develop a durable proton-exchange membrane (PEM) for fuel-cell applications, a series of sulfonated poly(benzoxazole thioether sulfone)s ( SPTESBOs) are designed and synthesized, with anticipated good dimensional stability (via acid–base cross linking), improved oxidative stability against free radicals (via incorporation of thioether groups), and enhanced inherent stability (via elimination of unstable end groups) of the backbone. The structures and the degree of sulfonation of the copolymers are characterized using Fourier-transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy ({sup 1}H NMR and {sup 19}F NMR). The electrochemical stabilities of the monomers are examined using cyclic voltammetry in a typical three-electrode cell configuration. The physicochemical properties of the membranes vital to fuel-cell performance are also carefully evaluated under conditions relevant to fuel-cell operation, including chemical and thermal stability, proton conductivity, solubility in different solvents, water uptake, and swelling ratio. The new membranes exhibit low dimensional change at 25°C to 90°C and excellent thermal stability up to 250°C. Upon elimination of unstable end groups, the co-polymers display enhanced chemical resistance and oxidative stability in Fenton's test. Further, the SPTESBO-HFB-60 (HFB-60=hexafluorobenzene, 60 mol% sulfone) membrane displays comparable fuel-cell performance to that of an NRE 212 membrane at 80°C under fully humidified condition, suggesting that the new membranes have the potential to be more durable but less expensive for fuel-cell applications.

  6. A durable alternative for proton-exchange membranes: sulfonated poly(benzoxazole thioether sulfone)s

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Dan [Center for Innovative Fuel Cell and Battery Technologies, School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0245 (United States); Lab of PEMFC Key Materials and Technologies, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Liaoning, Dalian 116023 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100039 (China); Li, Jinhuan [Center for Innovative Fuel Cell and Battery Technologies, School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0245 (United States); College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Song, Min-Kyu; Liu, Meilin [Center for Innovative Fuel Cell and Battery Technologies, School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0245 (United States); Yi, Baolian; Zhang, Huamin [Lab of PEMFC Key Materials and Technologies, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Liaoning, Dalian 116023 (China)

    2011-03-18

    To develop a durable proton-exchange membrane (PEM) for fuel-cell applications, a series of sulfonated poly(benzoxazole thioether sulfone)s (SPTESBOs) are designed and synthesized, with anticipated good dimensional stability (via acid-base cross linking), improved oxidative stability against free radicals (via incorporation of thioether groups), and enhanced inherent stability (via elimination of unstable end groups) of the backbone. The structures and the degree of sulfonation of the copolymers are characterized using Fourier-transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy ({sup 1}H NMR and {sup 19}F NMR). The electrochemical stabilities of the monomers are examined using cyclic voltammetry in a typical three-electrode cell configuration. The physicochemical properties of the membranes vital to fuel-cell performance are also carefully evaluated under conditions relevant to fuel-cell operation, including chemical and thermal stability, proton conductivity, solubility in different solvents, water uptake, and swelling ratio. The new membranes exhibit low dimensional change at 25 C to 90 C and excellent thermal stability up to 250 C. Upon elimination of unstable end groups, the co-polymers display enhanced chemical resistance and oxidative stability in Fenton's test. Further, the SPTESBO-HFB-60 (HFB-60=hexafluorobenzene, 60 mol% sulfone) membrane displays comparable fuel-cell performance to that of an NRE 212 membrane at 80 C under fully humidified condition, suggesting that the new membranes have the potential to be more durable but less expensive for fuel-cell applications. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Lignin Sulfonation - A different Approach

    DEFF Research Database (Denmark)

    Bjørkmann, Anders

    2001-01-01

    . It was found that lignin is very reactive, that is why the sulfonation chemistry alone does not necessarily determine its dissolution rate. It became evident that the ultrastructure dispersion of lignin in wood is beneficial for its dissolution. For W, the rate was much higher at pH 1.5 than at 6. MW lignin....... Methylation had also a small rate effect for W, but again a large decrease for MWL....

  8. Overbased Calcium sulfonate Detergent Technology Overview

    Institute of Scientific and Technical Information of China (English)

    MA Qing-gao; MUIR Ronald J.

    2009-01-01

    Overbased calcium sulfonate is used widely as detergent in automotive and marine lubricants, as well as various industrial oil applications. In this paper, the process to produce overbased calcium sulfonate is overviewed. The sulfonate structure and molecular weight and its molecular weight distribution, the enclosed calcium carbonate nanoparticle size and crystalline structure, properties of the carrier oil, all influence its properties, such as stability, viscosity, and detergency of the system.

  9. Copolymers of fluorinated polydienes and sulfonated polystyrene

    Science.gov (United States)

    Mays, Jimmy W.; Gido, Samuel P.; Huang, Tianzi; Hong, Kunlun

    2009-11-17

    Copolymers of fluorinated polydienes and sulfonated polystyrene and their use in fuel cell membranes, batteries, breathable chemical-biological protective materials, and templates for sol-gel polymerization.

  10. Polystyrene-supported Selenomethyl-sulfonates:Efficient Reagents for Stereocontrolled Synthesis of Substituted Vinyl Sulfones

    Institute of Scientific and Technical Information of China (English)

    Wei Ming XU; Lu Ling WU; Xian HUANG

    2004-01-01

    Polystyrene-supported selenomethyl-sulfonates have been prepared. These novel reagents were treated with LDA to produce selenium stabilized carbanions, which reacted with alkyl halide and epoxides, followed by selenoxide syn-elimination, to give E-vinyl sulfones and γ-hydroxy-substituted-E-vinyl sulfones respectively.

  11. Combined effects of cadmium and linear alkyl benzene sulfonate on Lemna minor L.

    Science.gov (United States)

    Singh, J; Chawla, G; Naqvi, S H; Viswanathan, P N

    1994-03-01

    : The effects of 0.1 ppm cadmium and 0.005% linear alkyl benzene sulfonates (LAS) on the uptake and metabolic incorporation of (14)C glycine by Lemna minor L., after 2, 24 and 48 h were studied for antagonistic/synergistic effects. Combined exposure was found to decrease the (14)C incorporation into proteins, DNA, RNA and phospholipids, to a greater extent than individual exposure. The presence of LAS increased the uptake of (109)Cd in the plants.

  12. 4-Aminopyridinium-3-sulfonate monohydrate

    Directory of Open Access Journals (Sweden)

    Zhi-Biao Zhu

    2011-02-01

    Full Text Available The reaction of 4-aminopyridine and oleum yielded the title hydrated zwitterion, C5H6N2O3S·H2O. There are two formula units in the asymmetric unit. The H and non-H atoms of both zwitterions lie on a mirror plane except for one sulfonate O atom. The water molecules are also situated on a mirror plane. In the crystal, the zwitterions and water molecules are linked by O—H...O and N—H...O hydrogen bonds, generating a three-dimensional network.

  13. Synthesis and characterization of sulfonated poly(ether sulfone)s containing mesonaphthobifluorene for polymer electrolyte membrane fuel cell.

    Science.gov (United States)

    Lim, Youngdon; Seo, Dongwan; Lee, Soonho; Hossain, Md Awlad; Lim, Jinseong; Lee, Sangyoung; Hong, Taehoon; Kim, Whangi

    2014-10-01

    The novel sulfonated poly(ether sulfone)s containing mesonaphthobifluorene (MNF) moiety were synthesized and characterized their properties. The prepared polymers have highly conjugated aromatic structure due to the MNF group which is an allotrope of carbon and one atom thick planar sheets of sp2-bonded carbon atoms. Poly(ether sulfone)s bearing tetraphenylethylene on polymer backbone were synthesized by polycondensation and followed intra-cyclization from tetraphenylethylene to form MNF by Friedel-craft reaction with Lewis acid (FeCl3). The sulfonation was performed selectively on MNF units with conc. sulfuric acid. The structural properties of the sulfonated polymers were investigated by 1H-NMR spectroscopy. The membranes were studied by ion exchange capacity (IEC), water uptake, and proton conductivity. The synthesized polymer electrolyte membranes showed better thermal and dimensional stabilities owing to the inducted highly conjugated aromatic structure in the polymer backbone. The water uptake of the synthesized membranes ranged from 23-52%, compared with 32.13% for Nafion 211 at 80 degrees C. The synthesized membranes exhibited proton conductivities (80 degrees C, RH 90%) of 74.6-100.4 mS/cm, compared with 102.7 mS/cm for Nafion 211.

  14. Synthesis of Linear Alkylbenzene in a Novel Liquid-Solid Circulating Moving Bed Reactor

    Institute of Scientific and Technical Information of China (English)

    韩明汉; 徐聪; 崔哲; 金涌

    2004-01-01

    For the alkylation of benzene with long-chain olefins, using Hβ zeolite catalyst as replacement of HF or A1Cl3 has the advantages of no corrosion, less environmental pollution, and much more 2-phenyl isomer, which has the highest biodegradability and solubility, and better detergent properties among the related isomers. The characterization of the coke shows that the deactivation of catalyst is caused by the jam of bulkier molecules, such as naphthalene, indane and linear alkylbenzenes, which are too big to move quickly in the intracrystalline pores of catalyst. The deactivated catalyst can be regenerated by benzene washing at higher temperature. To make the processes of reaction and regeneration continuous, a novel moving bed reactor is developed. Comparing with the processes with fixed bed reactors, the processes in this work have the advantages of continuous operation, low temperature, low pressure, low mole ratio of benzene to olefins, and high weight hourly space velocity.Keywords t3 zeolite, alkylation, linear alkylbenzene, moving bed reactor

  15. Chlorine resistant desalination membranes based on directly sulfonated poly(arylene ether sulfone) copolymers

    Science.gov (United States)

    McGrath, James E.; Park, Ho Bum; Freeman, Benny D.

    2011-10-04

    The present invention provides a membrane, kit, and method of making a hydrophilic-hydrophobic random copolymer membrane. The hydrophilic-hydrophobic random copolymer membrane includes a hydrophilic-hydrophobic random copolymer. The hydrophilic-hydrophobic random copolymer includes one or more hydrophilic monomers having a sulfonated polyarylsulfone monomer and a second monomer and one or more hydrophobic monomers having a non-sulfonated third monomer and a fourth monomer. The sulfonated polyarylsulfone monomer introduces a sulfonate into the hydrophilic-hydrophobic random copolymer prior to polymerization.

  16. Genotoxic effects of linear alkyl benzene sulfonate, sodium pentachlorophenate and dichromate on Tetrahymena pyriformis.

    Science.gov (United States)

    Wu, Y; Shen, Y

    1992-01-01

    DNA in macro- and micronuclei of Tetrahymena pyriformis treated with linear alkyl benzene sulfonate (LAS) and sodium pentachlorophenate (PCP-Na) were determined by microspectrophotometry. The effects on rate of formation of macronuclear DNA extrusion bodies were also studied. We found DNA content of micronuclei in 0.14 ppm LAS and 0.9 ppb PCP-Na was lower than in that of the control, and LAS was able to increase the formation rate of macronuclear DNA extrusion bodies (the formation rate was 54% in 11.3 ppm LAS and 25.6% in 16.7 ppm dichromate). We concluded that 0.14 ppm LAS (below the maximum acceptable toxicant concentration) was genotoxic, whereas 0.014 ppm LAS was not. Dichromate 0.05 ppm and 0.9 ppb PCP-Na, equal to and below the maximum acceptable toxicant concentration, respectively, were potentially genotoxic.

  17. Sulfonation of vulcanized ethylene-propylene-diene terpolymer membranes

    Energy Technology Data Exchange (ETDEWEB)

    Barroso-Bujans, F. [Instituto de Ciencia y Tecnologia de Polimeros, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain)], E-mail: fbarroso@ictp.csic.es; Verdejo, R.; Lozano, A. [Instituto de Ciencia y Tecnologia de Polimeros, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Fierro, J.L.G. [Instituto de Catalisis y Petroleoquimica, CSIC, Marie Curie 2, Cantoblanco, 28049 Madrid (Spain); Lopez-Manchado, M.A. [Instituto de Ciencia y Tecnologia de Polimeros, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain)

    2008-10-15

    In the present work, sulfonation of previously vulcanized ethylene propylene diene terpolymer (EPDM) membranes was developed in a swelling solvent with acetyl sulfate. This procedure avoids the need to pre-dissolve the raw polymer. The reaction conditions were optimized in terms of solvent type, reaction time, acetyl sulfate concentration and film thickness to obtain the maximum degree of sulfonation of the polymer. The sulfonation procedure presented in this study yields a degree of sulfonation comparable to the chlorosulfonic acid procedure. Sulfonic acid groups were detected by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy, and quantified by titrations. Proton conductivity and water uptake were measured by means of impedance spectroscopy and swelling measurements, respectively, and were correlated with the degree of sulfonation. Tensile strength and Young's modulus of sulfonated EPDM increased with the degree of sulfonation, while elongation at break remained constant. Thermal stability of the sulfonated EPDM was studied by simultaneous thermogravimetry-mass spectroscopy.

  18. Aqueous solubilities, vapor pressures, and 1-octanol-water partition coefficients for C9-C14 linear alkylbenzenes

    Science.gov (United States)

    Sherblom, P.M.; Gschwend, P.M.; Eganhouse, R.P.

    1992-01-01

    Measurements and estimates of aqueous solubilities, 1-octanol-water partition coefficients (Kow), and vapor pressures were made for 29 linear alkylbenzenes having alkyl chain lengths of 9-14 carbons. The ranges of values observed were vapor pressures from 0.002 to 0.418 Pa, log Kow, from 6.83 to 9.95, and aqueous solubilities from 4 to 38 nmol??L-1. Measured values exhibited a relationship to both the alkyl chain length and the position of phenyl substitution on the alkyl chain. Measurement of the aqueous concentrations resulting from equilibration of a mixture of alkylbenzenes yielded higher than expected values, indicating cosolute or other interactive effects caused enhanced aqueous concentrations of these compounds. ?? 1992 American Chemical Society.

  19. Susceptibility of Candida albicans to new synthetic sulfone derivatives.

    Science.gov (United States)

    Staniszewska, Monika; Bondaryk, Małgorzata; Ochal, Zbigniew

    2015-02-01

    The influence of halogenated methyl sulfones, i.e. bromodichloromethyl-4-chloro-3-nitrophenyl sulfone (named halogenated methyl sulfone 1), dichloromethyl-4-chloro-3-nitrophenyl sulfone (halogenated methyl sulfone 2), and chlorodibromomethyl-4-hydrazino-3-nitrophenyl sulfone (halogenated methyl sulfone 3), on cell growth inhibition, aspartic protease gene (SAP4-6) expression, adhesion to epithelium, and filamentation was investigated. Antifungal susceptibility of the halogenated methyl sulfones was determined with the M27-A3 protocol in the range of 16-0.0313 µg/mL. Adherence to Caco-2 cells was performed in 24-well plates; relative quantification was normalized against ACT1 in cells after 18 h of growth in YEPD and on Caco-2 cells. SAP4-6 expression was analyzed using RT-PCR. Structure-activity relationship studies suggested that halogenated methyl sulfone 1 containing bromodichloromethyl or dichloromethyl function at C-4 (halogenated methyl sulfone 2) of the phenyl ring showed the best activity (100% cell inhibition at 0.5 µg/mL), while hydrazine at C-1 (halogenated methyl sulfone 3) reduced the sulfone potential (100% = 4 µg/mL). SAP4-6 were up- or down-regulated depending on the strains' genetic background and the substitutions on the phenyl ring. Halogenated methyl sulfone 2 repressed germination and affected adherence to epithelium (P ≤ 0.05). The tested halogenated methyl sulfones interfered with the adhesion of Candida albicans cells to the epithelial tissues, without affecting their viability after 90 min of incubation. The mode of action of the halogenated methyl sulfones was attributed to the reduced virulence of C. albicans. SAP5 and SAP6 contribute to halogenated methyl sulfones resistance. Thus, halogenated methyl sulfones can inhibit biofilm formation due to their interference with adherence and with the yeast-to-hyphae transition.

  20. Interaction of apo cytochrome c with sulfonated polystyrene nanoparticles.

    Science.gov (United States)

    Liang, Li; Yao, Ping; Gong, Jie; Jiang, Ming

    2004-04-13

    Stable nanoparticle dispersion in aqueous solutions was obtained with partially sulfonated polystyrene. The hydrophobic association of the backbone chains and phenyl groups is balanced by the electrostatic repulsion of the sulfonate groups on the particle surface. The size distribution of the sulfonated polystyrene particles in relation to concentration, degree of sulfonation and chain length, and pH was characterized by dynamic laser light-scattering. The structure and morphology of the particles were characterized with fluorescence and atom force microscopy. Highly sulfonated polystyrene particles can form large complex particles with positively charged protein, apo cytochrome c. Dynamic laser light-scattering and atom force microscopy studies show that the size and distribution of the complex particles depend on the relative amount of apo cytochrome c and sulfonated polystyrene. When sulfonated polystyrene is in excess, apo cytochrome c interacts with sulfonated polystyrene particles forming stable complexes and excessive sulfonated polystyrene particles bind to the periphery of the complexes preventing them from further aggregation. When apo cytochrome c is in excess, apo cytochrome c links the complexes forming much larger particles. Fluorescence study demonstrates that the hydrophobicity/hydrophility of the complex particles is relative to the ratio of apo cytochrome c and sulfonated polystyrene, degree of sulfonation, and pH. Apo cytochrome c not only can neutralize the negative charges on the surface of sulfonated polystyrene particles, but may also insert into the cores disrupting the original structure of sulfonated polystyrene particles.

  1. Fluorescent Polystyrene Sulfonate for Polyelectrolyte Studies

    Science.gov (United States)

    Huberty, Wayne; Tong, Xiaowei; Balamurugan, Sreelatha; Zhang, Donghui; Russo, Paul

    2012-02-01

    The slow-mode decay found by dynamic light scattering for polyelectrolytes in low-salt conditions has perplexed investigators since its first observation. Many characterization methods have suggested temporary or transient aggregation, although there is still no consensus on the cause. Many different polyelectrolytes demonstrate the slow-mode decay, but the sodium salt of polystyrene sulfonate (NaPSS) is the most popular choice for study. Commercially available NaPSS may have hydrophobic patches due to incomplete sulfonation leading to associations apart from any putative ionic mechanisms. Therefore, essentially full sulfonation, or ``patchless'', NaPSS should be synthesized. To facilitate fluorescence measurements, which can provide new insights to the slow-mode phenomenon, the material must be rendered fluorescent (F-NaPSS). Several approaches to F-NaPSS have appeared; some labeled a previously synthesized NaPSS without concern for its hydrophobic patches. Other strategies include a free radical copolymerization of styrene sulfonate and a vinyl amine to provide side chains viable for labeling. This method is successful, but yields only small amounts of nearly monodisperse polymer after fractionation. In this presentation, a high-yield synthesis of fully sulfonated, low-polydispersity, fluorescently tagged polymer will be discussed.

  2. Corrosion of Reinforcing Steel in Concrete Immersed in Chloride Solution and the Effects of Detergent Additions on Diffusion and Concrete Porosity

    OpenAIRE

    2002-01-01

    In order to investigate the corrosion of reinforcing steel in concrete and the effects of chloride ions, oxygen diffusion and detergent additives of linear alkylbenzene (LAB) and linear alkylbenzene sulfonate (LAS), potentiokinetic experiments were carried out. Thus, by embedding steel electrodes into concrete specimens with a water/cement (W/C) ratio of 0.45, current-potential curves were obtained and the compressive strength of the specimens was measured. The electrochemical appro...

  3. Reinforced films based on cross-linked water-soluble sulfonated carbon nanotubes with sulfonated polystyrene.

    Science.gov (United States)

    Dai, Ying; Haiping, Hong; Guiver, Michael; Welsh, Jeffry S

    2009-09-01

    Reinforced films based on sulfonated polystyrene cross-linked with water-soluble sulfonated carbon nanotubes were fabricated using a free-standing film-making method. Transmission and scanning electron microscopy (TEM and SEM), and X-ray photoelectron spectroscopy (XPS) were used to verify the cross-linking reaction. The mechanical properties of these films demonstrated that the tensile strength increases with an increase in the sulfonated nanotube concentration. At 5 wt% nanotube loading, the tensile strength increased 84% compared with polymer containing no nanotube loading. The relationships between structure and mechanical properties are discussed and a possible direction for making ultra thin and ultra lightweight film is proposed.

  4. Reinforced membrane based on crosslink reaction between water soluble sulfonated carbon nanotubes and sulfonated polystyrene

    Science.gov (United States)

    Dai, Ying; Hong, Haiping; Welsh, Jeffry S.

    2008-08-01

    Reinforced films based on sulfonated polystyrene cross-linked with water-soluble sulfonated carbon nanotubes were fabricated using a free-standing film-making method. Transmission and scanning electron microscopy, X-ray photoelectron spectroscopy, and thermo-gravimetric analysis were used to verify the cross-linking reaction. The mechanical properties of these films demonstrated that the tensile strength increases with an increase in the sulfonated nanotube concentration. At 5 wt% nanotube loading, the tensile strength increased 84% compared with polymer containing no nanotube loading. The relationships between structure and mechanical properties are discussed and a possible direction for making ultra thin and ultra lightweight film is proposed

  5. The facile insertion of β-keto sulfones to arynes: The direct preparation of polysubstituted ortho-keto benzyl sulfones

    Institute of Scientific and Technical Information of China (English)

    Jian Xue; Lu Ling Wu; Xian Huang

    2008-01-01

    One novel carbon-carbon bond insertion reaction of arynes has been developed. By this reaction β-keto sulfones can insert the triple bond of arynes to prepare polysubstituted ortho-keto benzyl sulfones.

  6. 21 CFR 177.2500 - Polyphenylene sulfone resins.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Polyphenylene sulfone resins. 177.2500 Section 177... Components of Articles Intended for Repeated Use § 177.2500 Polyphenylene sulfone resins. The polyphenylene sulfone resins (CAS Reg. No. 31833-61-1) identified in paragraph (a) of this section may be safely used...

  7. Mouse determinant lethal and bone marrow micronucleus studies on methyl vinyl sulfone and divinyl sulfone

    OpenAIRE

    1991-01-01

    Artículo científico-- Instituto de Investigaciones en Salud-- 1991. La revista no permite distribuir la versión final del documento. Methyl vinyl sulfone and divinyl sulfone were tested for the induction of dominant lethal mutations and micronucleated bone-marrow erythrocytes in male mice. These chemicals were chosen for study because of their similarities in structure and chemical reactivity to acrylamide which is known to induce both effects. Following administration of the test...

  8. Carbon dioxide sensing with sulfonated polyaniline

    NARCIS (Netherlands)

    Doan, D.C.T.; Ramaneti, R.; Baggerman, J.; Bent, van der J.; Marcelis, A.T.M.; Tong, H.D.; Rijn, van C.J.M.

    2012-01-01

    The use of polyaniline and especially sulfonated polyaniline (SPAN) is explored for sensing carbon dioxide (CO2) at room temperature. Frequency-dependent AC measurements were carried out to detect changes in impedance of the polymer, drop casted on interdigitated electrodes, when exposed to CO2 gas.

  9. Fate and biodegradability of sulfonated aromatic amines

    NARCIS (Netherlands)

    Tan, N.C.G.; Leeuwen, van A.; Voorthuizen, van E.M.; Slenders, P.; Prenafeta, F.X.; Temmink, H.; Lettinga, G.; Field, J.A.

    2005-01-01

    Ten sulfonated aromatic amines were tested for their aerobic and anaerobic biodegradability and toxicity potential in a variety of environmental inocula. Of all the compounds tested, only two aminobenzenesulfonic acid (ABS) isomers, 2- and 4-ABS, were degraded. The observed degradation occurred only

  10. Modeling the Conformation-Specific Infrared Spectra of N-Alkylbenzenes

    Science.gov (United States)

    Tabor, Daniel P.; Sibert, Edwin; Hewett, Daniel M.; Korn, Joseph A.; Zwier, Timothy S.

    2016-06-01

    Conformation-specific UV-IR double resonance spectra are presented for n-alkylbenzenes. With the aid of a local mode Hamiltonian that includes the effects of stretch-bend Fermi coupling, the spectra of ethyl, n-propyl, and n-butylbenzene are assigned to individual conformers. These molecules allow for further development of the work on a first principles method for calculating alkyl stretch spectra. Due to the consistency of the anharmonic couplings from conformer to conformer, construction of the model Hamiltonian for a given conformer only requires a harmonic frequency calculation at the conformer's minimum geometry as an input. The model Hamiltonian can be parameterized with either density functional theory or MP2 electronic structure calculations. The relative strengths and weaknesses of these methods are evaluated, including their predictions of the relative energetics of the conformers. Finally, the IR spectra for conformers that have the alkyl chain bend back and interact with the π cloud of the benzene ring are modeled.

  11. Sulindac Sulfide, but Not Sulindac Sulfone, Inhibits Colorectal Cancer Growth

    Directory of Open Access Journals (Sweden)

    Christopher S. Williams

    1999-06-01

    Full Text Available Sulindac sulfide, a metabolite of the nonsteroidal antiinflammatory drug (NSAID sulindac sulfoxide, is effective at reducing tumor burden in both familial adenomatous polyposis patients and in animals with colorectal cancer. Another sulindac sulfoxide metabolite, sulindac sulfone, has been reported to have antitumor properties without inhibiting cyclooxygenase activity. Here we report the effect of sulindac sulfone treatment on the growth of colorectal carcinoma cells. We observed that sulindac sulfide or sulfone treatment of HCA-7 cells led to inhibition of prostaglandin E2 production. Both sulindac sulfide and sulfone inhibited HCA-7 and HCT-116 cell growth in vitro. Sulindac sulfone had no effect on the growth of either HCA-7 or HCT-116 xenografts, whereas the sulfide derivative inhibited HCA-7 growth in vivo. Both sulindac sulfide and sulfone inhibited colon carcinoma cell growth and prostaglandin production in vitro, but sulindac sulfone had no effect on the growth of colon cancer cell xenografts in nude mice.

  12. Influence of LAS on marine calanoid copepod population dynamics and potential reproduction

    DEFF Research Database (Denmark)

    Christoffersen, Kirsten; Hansen, Benni Winding; Johansson, Liselotte Sander

    2003-01-01

    The toxicity of linear alkyl benzene sulfonate (LAS) to marine invertebrates is well documented under laboratory conditions using single-species tests. It is less known how LAS affects natural populations of aquatic organisms. We hypothesised that LAS was more toxic to the calanoid copepod Acarti...

  13. Highly branched sulfonated poly(fluorenyl ether ketone sulfone)s membrane for energy efficient vanadium redox flow battery

    Science.gov (United States)

    Yin, Bibo; Li, Zhaohua; Dai, Wenjing; Wang, Lei; Yu, Lihong; Xi, Jingyu

    2015-07-01

    A series of highly branched sulfonated poly (fluorenyl ether ketone sulfone)s (HSPAEK) are synthesized by direct polycondensation reactions. The HSPAEK with 8% degree of branching is further investigated as membrane for vanadium redox flow battery (VRFB). The HSPAEK membrane prepared by solution casting method exhibits smooth, dense and tough morphology. It possesses very low VO2+ permeability and high ion selectivity compared to those of Nafion 117 membrane. When applied to VRFB, this novel membrane shows higher coulombic efficiency (CE, 99%) and energy efficiency (EE, 84%) than Nafion 117 membrane (CE, 92% and EE, 78%) at current density of 80 mA cm-2. Besides, the HSPAEK membrane shows super stable CE and EE as well as excellent discharge capacity retention (83%) during 100 cycles life test. After being soaked in 1.5 mol L-1 VO2+ solution for 21 days, the weight loss of HSPAEK membrane and the amount of VO2+ reduced from VO2+ are only 0.26% and 0.7%, respectively, indicating the superior chemical stability of the membrane.

  14. STUDY ON LIGHTLY SULFONATED SYNDIOTACTIC POLYSTYRENE IONOMERS

    Institute of Scientific and Technical Information of China (English)

    Jin Wang; Fang-ming Zhu; Jin-cheng Lui; Hua-ming Li; Shang-an Lin

    2001-01-01

    ulfonated syndiotactic polystyrene ionomers (SsPS) with 1.8 mol% degree of sulfonation have been studied.SWAXD shows that the crystallinity of SsPS ionomers was decreased with increasing diameter size of the counter ions and sPS > SsPS-H > SsPS-K > SsPS-Zn. Moreover, SsPS ionomers only have α crystal form, while original sPS has two crystal forms: α and β crystal form. TGA shows that the thermal stability of SsPS ionomers is higher than that of the original sPS and SsPS-Zn > SsPS-K > SsPS-H. DSC shows that all the glass transition temperatures (Tg) of SsPS ionomers are higher than that of the neat sPS and SsPS-Zn > SsPS-Na > SsPS-K > SsPS-H. However, the melting temperature (Tm) and crystallization peak temperature (Tp) of SsPS ionomers are lower and SsPS-H > SsPS-Zn > SsPS-K > SsPS-Na, while the crystallinity (Xc) of SsPS-Zn is the lowest. Nonisothermal crystallization kinetics shows that the Avrami index of sPS and SsPS-H are both about 4, suggesting the nucleation growth of SsPS-H with lower degree of sulfonation still keeps its threedimension form. FTIR spectra of SsPS ionomers show a splitting absorption band for asymmetric stretching vibration of sulfonation group. The CH in-plane bending vibration of benzene ring shifted to higher wavenumber and the symmetric stretching vibration of sulfonation group changed slightly with different counter ion neutralized SsPS ionomers.

  15. The Effect of Sulfonation and Neutralization on the Dynamics of Zn Neutralized Sulfonated Polystyrene Ionomers

    Science.gov (United States)

    Castagna, Alicia; Wang, Wenqin; Winey, Karen I.; Runt, James

    2011-03-01

    The effect of sulfonation and neutralization levels on structure and dynamics of Zn neutralized sulfonated polystyrene (SPS) ionomers were investigated using scanning transmission electron microscopy (STEM), X-ray scattering, and dielectric relaxation spectroscopy. STEM and X-ray scattering revealed the presence of spherical aggregates 2 nm in diameter. Successful fitting of the scattering data to the Kinning-Thomas modified hard sphere model revealed that aggregate size is independent of degree of sulfonation and neutralization level, and that aggregate composition becomes increasingly ionic with increasing neutralization. Two segmental relaxations were identified in dielectric loss spectra corresponding to cooperative motion of chain segments in the unrestricted matrix and motions of chain segments restricted by aggregates. A Maxwell-Wagner-Sillars interfacial polarization process was revealed, with relaxation times that were in good agreement with predictions from a simple model of dispersed ionic spheres.

  16. SULFONATION OF A NEW POLYETHERETHERKETONE PREPARED FROM PHENOLPHTHALEIN

    Institute of Scientific and Technical Information of China (English)

    CHEN Tianlu; YUAN Yagui; ZHANG Manhua; CHEN Zhongqing; XU Jiping

    1990-01-01

    A novel polyetheretherketone (PEK-C) prepared from phenolphthalein has been synthesized. In order to improve some of its properties for application in high performance membrane, the PEK-C has been sulfonated with concentrated sulfuric acid. Degree of sulfonation can be regulated by controlling the temperature and time of sulfonation. The characterization of the sulfonated PEK-C in sodium salt form has been made by IR, 1H NMR and 13C NMR etc. It is shown that the sulfonation appears to take place exclusively in the ortho position to phenolic ether of phenolphthalein unit. The result is in agreement with theoretical deduction. Some properties of the sulfonated PEK-C, such as solubility, transition temperature, thermal degradation and hydrophilicity have also been discussed.

  17. Phosphorus-containing sulfonated polyimides for proton exchange membranes

    OpenAIRE

    2008-01-01

    Synthesis and characterization of the novel sulfonated BAPPO monomer and its use in the synthesis of a new phosphine oxide-based sulfonated polyimide are described. BTDA, 6FDA, and DDS were used as monomers in the polyimide synthesis. Sulfonated polyimide membranes were obtained by a solution thermal imidization method. The thermal behavior of the polymers was investigated by DSC and TGA. The morphological structure of the membranes was investigated by tapping-mode AFM. The proton conductivit...

  18. Preparation of Sulfonated Poly(aryl ether sulfone) Electrospun Mat/Phosphosilicate Composite Proton Exchange Membrane

    Science.gov (United States)

    Wang, Limei; Dou, Liyan; Guan, Guoying

    2017-01-01

    Side-chain-type sulfonated poly(aryl ether sulfone) (SPES) was synthesized and then electrospun into mats. Phosphosilicate glass (PS) via in situ sol-gel synthesis was enclosed in the mats to form a new reinforced composite membrane. The SPES/PS composite membranes showed satisfactory dimensional change behavior with varying humidity. Especially, the composite membrane exhibits excellent proton conductivity at harsh measurement conditions of low humidity at 80°C. The composite membrane with outstanding combined properties has potential applications for high temperature polymer electrolyte membrane fuel cells.

  19. Preparation of Sulfonated Poly(aryl ether sulfone) Electrospun Mat/Phosphosilicate Composite Proton Exchange Membrane

    Science.gov (United States)

    Wang, Limei; Dou, Liyan; Guan, Guoying

    2017-03-01

    Side-chain-type sulfonated poly(aryl ether sulfone) (SPES) was synthesized and then electrospun into mats. Phosphosilicate glass (PS) via in situ sol-gel synthesis was enclosed in the mats to form a new reinforced composite membrane. The SPES/PS composite membranes showed satisfactory dimensional change behavior with varying humidity. Especially, the composite membrane exhibits excellent proton conductivity at harsh measurement conditions of low humidity at 80°C. The composite membrane with outstanding combined properties has potential applications for high temperature polymer electrolyte membrane fuel cells.

  20. Synthesis and Characterization of Ion-exchange Sulfonated Poly (ether sulfone)

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    N,N'-Bis(3-hydroxyphenyl)-1,8,4,5-naphthalenetetracarboxylic bisimide was prepared from the reaction of 1,8,4,5-naphthalenetetrcarboxylic acid dianhydride and 2-aminophenol in N,N-dimethylformamide. Polymerization of this bisimide with 4,4'-difluorodiphenylsulfone and disodium 3,3'-disulfonate4,4'-difluorodiphenylsulfone gave ion-exchange sulfonated poly(ether sulfone). The structure of the title compound was characterized with 1H-NMR and its polymer was characterized with FT-IR.

  1. Where's the Bend? Locating the First Folded Structure in Straight Chain Alkylbenzenes in a Supersonic Jet Expansion

    Science.gov (United States)

    Hewett, Daniel M.; Bocklitz, Sebastian; Suhm, Martin A.; Zwier, Timothy S.

    2016-06-01

    Alkylbenzenes make up 20-30% of petroleum fuels and are important intermediates in combustion. In gasoline, these alkyl chains are relatively short, but extend to 20 or more carbons in length in diesel fuels. While one tends to think of these chains as extending out away from the phenyl ring in an all-trans configuration, dispersive interactions between segments of the alkyl chain and between the alkyl chain and the ring will stabilize more compact geometries in which the alkyl chain folds back on itself and extends over the aromatic π cloud. This talk seeks to answer the following question: How long must the alkyl chain be before it starts to fold back over itself? Studies of the pure n-alkanes by the Suhm group have shown the turn to favorably occur for a chain about 17 carbon atoms in length. The studies presented here focus on the affect the aromatic ring has on when this turn becomes favorable. Jet-cooled laser-induced fluorescence excitation and single-conformation IR spectra have been recorded in the alkyl CH stretch region for a series of alkylbenzenes with chain lengths ranging from two to ten carbon atoms. We show, through a combination of experiment, high level calculation, and theoretical modeling, that conformations begin to form that fold back over the aromatic ring at about n=8.

  2. Effect of linear alkyl benzene sulfonate on germination of spores of the aquatic fern Ceratopteris thalictroides

    Energy Technology Data Exchange (ETDEWEB)

    Singh, J.; Devi, S. (National Botanical Research Institute, Lucknow (India))

    1989-07-01

    Validity of fern spore germination bioassays for the effects of environmental pollution was established by many researchers. Some workers studied the phytotoxicity of linear alkyl benzene sulfonate (LAS) on the spores of Diplazium esculentum and observed that LAS levels above 0.001% are toxic to fern spores. Water pollution due to synthetic detergents has been increasing continuously during the last few years due to their extensive use in domestic life, agriculture and industry. These detergents are among the most common pollutants responsible for water pollution. In view of this fact, the phytotoxicity of LAS on germination of an aquatic fern Ceratopteris thalictroides spores was studied. However, in these studies, only germination pattern was taken as index and no observations were made on the developmental stages.

  3. Blending of styrene-block-butadiene-block-styrene copolymer with sulfonated vinyl aromatic polymers

    OpenAIRE

    Ruggeri, Giacomo; Passaglia, Elisa; Giorgi, Ivan; Picchioni, Francesco; Aglietto, Mauro

    2001-01-01

    Different polymers containing sulfonic groups attached to the phenyl rings were prepared by sulfonation of polystyrene (PS) and styrene-block-(ethylene-co-1-butene)-block-styrene (SEBS). The sulfonation degree (SD) was varied between 1 and 20 mol% of the styrene units. Polyphase materials containing sulfonated units were prepared by blending styrene-block-butadiene-block-styrene (SBS), with both sulfonated PS and sulfonated SEBS in a Brabender mixer. Such a procedure was performed as an alter...

  4. Molecular sieve/sulfonated poly(ether ketone ether sulfone) composite membrane as proton exchange membrane

    Science.gov (United States)

    Changkhamchom, Sairung; Sirivat, Anuvat

    2012-02-01

    A proton exchange membrane (PEM) is an electrolyte membrane used in both polymer electrolyte membrane fuel cells (PEMFC) and direct methanol fuel cells (DMFCs). Currently, PEMs typically used for PEMFCs are mainly the commercially available Nafion^ membranes, which is high cost and loss of proton conductivity at elevated temperature. In this work, the Sulfonated poly(ether ketone ether sulfone), (S-PEKES), was synthesized by the nucleophilic aromatic substitution polycondensation between bisphenol S and 4,4'-dichlorobenzophenone, and followed by the sulfonation reaction with concentrated sulfuric acid. The molecular sieve was added in the S-PEKES matrix at various ratios to form composite membranes to be the candidate for PEM. Properties of both pure sulfonated polymer and composite membranes were compared with the commercial Nafion^ 117 membrane from Dupont. S-PEKES membranes cast from these materials were evaluated as a polymer electrolyte membrane for direct methanol fuel cells. The main properties investigated were the proton conductivity, methanol permeability, thermal, chemical, oxidative, and mechanical stabilities by using a LCR meter, Gas Chromatography, Thermogravimetric Analysis, Fourier Transform Infrared Spectroscopy, Fenton's reagent, and Universal Testing Machine. The addition of the molecular sieve helped to increase both the proton conductivity and the methanol stability. These composite membranes are shown as to be potential candidates for use as a Proton Exchange Membrane (PEM).

  5. Thermal and Dielectric Behavior Studies of Poly(Arylene Ether Sulfones with Sulfonated and Phosphonated Pendants

    Directory of Open Access Journals (Sweden)

    Shimoga D. Ganesh

    2016-01-01

    Full Text Available The present paper discusses the aspects of the synthesizing valeric acid based poly(ether sulfones with active carboxylic acid pendants (VALPSU from solution polymerization technique via nucleophilic displacement polycondensation reaction among 4,4′-dichlorodiphenyl sulfone (DCDPS and 4,4′-bis(4-hydroxyphenyl valeric acid (BHPA. The conditions necessary to synthesize and purify the polymer were investigated in some detail. The synthesized poly(ether sulfones comprise sulfone and ether linkages in addition to reactive carboxylic acid functionality; these active carboxylic acid functional groups were exploited to hold the phenyl sulphonic acid and phenyl phosphonic acid pendants. The phenyl sulphonic acid pendants in VALPSU were easily constructed by altering active carboxylic acid moieties by sulfanilic acid using N,N′-dicyclohexylcarbodiimide (DCC mediated mild synthetic route, whereas the latter one was built in two steps. Initially, polyphosphoric acid condensation with VALPSU by 4-bromoaniline and next straightforward palladium catalyzed synthetic route, in both of which acidic pendants are clenched by polymer backbone via amide linkage. Without impairing the primary polymeric backbone modified polymers were prepared by varying the stoichiometric ratios of respective combinations. All the polymers were physicochemically characterized and pressed into tablets; electrical contacts were established to study the dielectric properties. Finally, the influence of the acidic pendants on the dielectric properties was examined.

  6. Bisphenol A sulfonation is impaired in metabolic and liver disease

    Science.gov (United States)

    Yalcin, Emine B.; Kulkarni, Supriya R.; Slitt, Angela L.; King, Roberta

    2016-01-01

    Background Bisphenol A (BPA) is a widely used industrial chemical and suspected endocrine disruptor to which humans are ubiquitously exposed. Liver metabolizes and facilitates BPA excretion through glucuronidation and sulfonation. The sulfotransferase enzymes contributing to BPA sulfonation (detected in human and rodents) is poorly understood. Objectives To determine the impact of metabolic and liver disease on BPA sulfonation in human and mouse livers. Methods The capacity for BPA sulfonation was determined in human liver samples that were categorized into different stages of metabolic and liver disease (including obesity, diabetes, steatosis, and cirrhosis) and in livers from ob/ob mice. Results In human liver tissues, BPA sulfonation was substantially lower in livers from subjects with steatosis (23%), diabetes cirrhosis (16%), and cirrhosis (18%), relative to healthy individuals with non-fatty livers (100%). In livers of obese mice (ob/ob), BPA sulfonation was lower (23%) than in livers from lean wild-type controls (100%). In addition to BPA sulfonation activity, Sult1a1 protein expression decreased by 97% in obese mouse livers. Conclusion Taken together these findings establish a profoundly reduced capacity of BPA elimination via sulfonation in obese or diabetic individuals and in those with fatty or cirrhotic livers versus individuals with healthy livers. PMID:26712468

  7. Simulation and pre-feasibility analysis of the production process of alpha-methyl ester sulfonates (alpha-MES).

    Science.gov (United States)

    Martínez, Daniel; Orozco, Gustavo; Rincón, Sandra; Gil, Iván

    2010-11-01

    alpha-Methyl esters sulfonates (alpha-MES) are anionic surfactants that are derived from biorenewable resources, offering interesting environmental and chemical properties for application in the detergent industry. A simulation of their production process was conducted using a commercial production process currently used for palm oil. Results, prices of raw materials were submitted to economic analysis, and final MES price was compared with available data for linear alkyl benzene sulfonates (LAS) prices. The results for substances properties and product streams obtained from simulation were reliable in agreement to real values. It was found that increasing methyl ester national price by 20%, 50% and the equivalent to linear alkyl benzene price, the final price of alpha-methyl ester sulfonates was lower than the current price of linear alkyl benzene sulfonates. The capital cost and payout period for a production capacity of 49,000tons of surfactant per year were obtained. Results indicate that the process is economically feasible and can be applied to palm oil-based industries in Colombia.

  8. Controlling Structure in Sulfonated Block Copolymer Membranes

    Science.gov (United States)

    Truong, Phuc; Stein, Gila; Strzalka, Joe

    2015-03-01

    In many ionic block copolymer systems, the strong incompatibility between ionic and non-ionic segments will trap non-equilibrium structures in the film, making it difficult to engineer the optimal domain sizes and transport pathways. The goal of this work is to establish a framework for controlling the solid-state structure of sulfonated pentablock copolymer membranes. They have ABCBA block sequence, where A is poly(t-butyl styrene), B is poly(hydrogenated isoprene), and C is poly(styrene sulfonate). To process into films, the polymer is dissolved in toluene/n-propanol solvent mixtures, where the solvent proportions and the polymer loading were both varied. Solution-state structure was measured with small angle X-ray scattering (SAXS). We detected micelles with radii that depend on the solvent composition and polymer loading. Film structure was measured with grazing-incidence SAXS, which shows (i) domain periodicity is constant throughout film thickness; (ii) domain periodicity depends on solvent composition and polymer loading, and approximately matches the micelle radii in solutions. The solid-state packing is consistent with a hard sphere structure factor. Results suggest that solid-state structure can be tuned by manipulating the solution-state self-assembly.

  9. The Effects of Surfactants on the Desorption of Organic Contaminants from Aquifer Materials

    Science.gov (United States)

    1989-08-01

    Wilmington Delaware, April 11, 1989. Cox, M. F. and K. L. Matheson. "Interactions between Linear Alkylbenzene Sulfonates and Water Hardness Ions. II. Reducing...Between Linear Alkylbenzene Sulfonates and Water Hardness Ions. I. Effect of Calcium Ion on Surfactant Solubility and Implications for Detergency...Fatty acids Sulfonate Paraffins Sulfate Olefins Carboxylate Alkylbenzenes Quaternary ammonium Long chain alcohols Protonated amine Alkyl Phenols

  10. Comparing sensitivity of ecotoxicological effect endpoints between laboratory and field

    DEFF Research Database (Denmark)

    Selck, H.; Riemann, B.; Christoffersen, K.

    2002-01-01

    multispecies field tests using tributyltin (TBT) and linear alkylbenzene sulfonates (LAS) were compared with published laboratory single-species test results and measured in situ concentrations. Extrapolation methods were evaluated by comparing predicted no-effect concentrations (PNECs), calculated by AF...

  11. Rh-Catalyzed Asymmetric Hydrogenation of α-Substituted Vinyl Sulfones: An Efficient Approach to Chiral Sulfones.

    Science.gov (United States)

    Shi, Liyang; Wei, Biao; Yin, Xuguang; Xue, Peng; Lv, Hui; Zhang, Xumu

    2017-03-03

    Rh/(S)-(+)-DTBM-Segphos complex catalyzed asymmetric hydrogenation of α-substituted vinyl sulfones has been achieved, furnishing the desired products in high yields and excellent enantioselectivities (>90% yield, up to 99% ee). This method provided an efficient approach to α-substituted chiral sulfones under mild conditions and has potential applications in organic synthesis.

  12. Pengaruh Rasio Mol Reaktan dan Lama Sulfonasi terhadap Karakteristik Methyl Ester Sulfonic (MES) dari Metil Ester Minyak Sawit (Effects of Mol Ratio and Sulfonation Time on Methyl Ester Sulfonic (MES) Characteristics from Methyl Ester of Palm Oil)

    OpenAIRE

    Sri Hidayati; Pudji Permadi; Hestuti Eni

    2017-01-01

    An experiment of sulfonation process of methyl ester to produce methyl ester sulfonates (MES) was caried out using methyl ester palm oil in factorial design and NaHSO as sulfonating agent with variation of ratio mol NaHSO : methyl ester (1:1.25, 1:1.5, 1:1.75 and 1:2 ) and sulfonation time (3 hour (L1), 4.5 hour (L2) and 6 hour (L3). The result showed that the best sulfonation condition present in 1:1,5 mol ratio and sulfonation time of 4,5 hour. The best characteristic of MES was produced em...

  13. Synthesis and characterization of polymer blends of sulfonated polyethersulfone and sulfonated polyethersulfone octylsulfonamide for PEMFC applications

    Energy Technology Data Exchange (ETDEWEB)

    Mabrouk, W. [ERAS Labo, St Nazaire Les Eymes, Grenoble (France); Laboratoire des Materiaux Industriels, Conservatoire National des Arts et Metiers de Paris, 75003 Paris (France); Laboratoire de Chimie Analytique et Electrochimie, Faculte des Sciences de Tunis, Campus Universitaire, 1092 Tunis (Tunisia); Ogier, L.; Vidal, S. [ERAS Labo, St Nazaire Les Eymes, Grenoble (France); Sollogoub, C.; Fauvarque, J.F. [Laboratoire des Materiaux Industriels, Conservatoire National des Arts et Metiers de Paris, 75003 Paris (France); Matoussi, F.; Dachraoui, M. [Laboratoire de Chimie Analytique et Electrochimie, Faculte des Sciences de Tunis, Campus Universitaire, 1092 Tunis (Tunisia)

    2012-04-15

    Our goal in the present work was to synthesize a new proton exchange membrane that could be used in proton exchange membrane fuel cell (PEMFC), based on a blend of sulfonated polyethersulfone (S-PES) and sulfonated polyethersulfone octylsulfonamide (S-PESOS). Five blends, using S-PESOS with different grafting ratios of sulfonamide groups, have been elaborated, characterized, and tested in a PEMFC. The similar chemical structure between these two polymers favored their compatibility. The synthesized membranes showed a high water swelling capacity and an ionic conductivity equivalent to that of Nafion registered (0.1 S cm{sup -1}) in the same conditions. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Sulfonated polystyrene as a new gradient-index medium for light-focusing elements.

    Science.gov (United States)

    Jung, S D; Hwang, W Y; Song, S H; Lee, el-H; Lee, J I; Shim, H K

    1995-06-01

    We have discovered that the sulfonation of polystyrene can form a gradient-index medium useful for lightfocusing purposes. We found that the refractive index of sulfonated polystyrene varies with the degree of sulfonation and that the refractive index of the fully sulfonated polystyrene decreased by approximately 0.06 at 0.633 microm from that of pure polystyrene.

  15. Hydroquinone based sulfonated poly (arylene ether sulfone copolymer as proton exchange membrane for fuel cell applications

    Directory of Open Access Journals (Sweden)

    V. Kiran

    2015-12-01

    Full Text Available Synthesis of sulfonated poly (arylene ether sulfone copolymer by direct copolymerization of 4,4'-bis(4-hydroxyphenyl valeric acid, benzene 1,4-diol and synthesized sulfonated 4,4'-difluorodiphenylsulfone and its characterization by using FTIR (Fourier Transform Infrared and NMR (Nuclear Magnetic Resonance spectroscopic techniques have been performed. The copolymer was subsequently cross-linked with 4, 4!(hexafluoroisopropylidenediphenol epoxy resin by thermal curing reaction to synthesize crosslinked membranes. The evaluation of properties showed reduction in water and methanol uptake, ion exchange capacity, proton conductivity with simultaneous enhancement in oxidative stability of the crosslinked membranes as compared to pristine membrane. The performance of the membranes has also been evaluated in terms of thermal stability, morphology, mechanical strength and methanol permeability by using Thermo gravimetric analyzer, Differential scanning calorimetery, Atomic force microscopy, XPERT-PRO diffractometer, universal testing machine and diffusion cell, respectively. The results demonstrated that the crosslinked membranes exhibited high thermal stability with phase separation, restrained crystallinity, acceptable mechanical properties and methanol permeability. Therefore, these can serve as promising proton exchange membranes for fuel cell applications.

  16. Preparation of new proton exchange membranes using sulfonated poly(ether sulfone) modified by octylamine (SPESOS)

    Energy Technology Data Exchange (ETDEWEB)

    Mabrouk, W. [Societe ERAS Labo, 222 RN 90, 38330, St Nazaire Les Eymes, Grenoble (France); Laboratoire des Materiaux Industriels, Conservatoire National des Arts et Metiers de Paris 75003, Paris (France); Laboratoire de Chimie Analytique et Electrochimie, Faculte des Sciences de Tunis, Campus Universitaire 1092, Tunis (Tunisia); Ogier, L. [Societe ERAS Labo, 222 RN 90, 38330, St Nazaire Les Eymes, Grenoble (France); Matoussi, F. [Laboratoire de Chimie Analytique et Electrochimie, Faculte des Sciences de Tunis, Campus Universitaire 1092, Tunis (Tunisia); Sollogoub, C., E-mail: cyrille.sollogoub@cnam.fr [Laboratoire des Materiaux Industriels, Conservatoire National des Arts et Metiers de Paris 75003, Paris (France); Vidal, S. [Societe ERAS Labo, 222 RN 90, 38330, St Nazaire Les Eymes, Grenoble (France); Dachraoui, M. [Laboratoire de Chimie Analytique et Electrochimie, Faculte des Sciences de Tunis, Campus Universitaire 1092, Tunis (Tunisia); Fauvarque, J.F. [Laboratoire des Materiaux Industriels, Conservatoire National des Arts et Metiers de Paris 75003, Paris (France)

    2011-08-15

    Highlights: {yields} New, simple and cheap way to synthesize a membrane. {yields} The membranes combine good proton conductivities with good mechanical properties. {yields} The membrane performances in a fuel cell are similar to the Nafion 117. - Abstract: Sulfonated poly(arylene ether sulfone) (SPES) has received considerable attention in membrane preparation for proton exchange membrane fuel cell (PEMFC). But such membranes are brittle and difficult to handle in operation. We investigated new membranes using SPES grafted with various degrees of octylamine. Five new materials made from sulfonated polyethersulfone sulfonamide (SPESOS) were synthetized with different grades of grafting. They were made from SPES, with initially an ionic exchange capacity (IEC) of 2.4 meq g{sup -1} (1.3 H{sup +} per monomer unit). Pristine SPES with that IEC is water swelling and becomes soluble at 80 deg. C, its proton conductivity is in the range of 0.1 S cm{sup -1} at room temperature in aqueous H{sub 2}SO{sub 4} 1 M, similar to that of Nafion. After grafting with various amounts of octylamine, the material is water insoluble; membranes are less brittle and show sufficient ionic conductivity. Proton transport numbers were measured close to 1.

  17. Ionomeric membranes based on partially sulfonated poly(styrene): synthesis, proton conduction and methanol permeation

    OpenAIRE

    Picchioni, F.; Tricoli,V.; Carretta, N.

    2000-01-01

    Homogeneuosly sulfonated poly(styrene) (SPS) was prepared with various concentration of sulfonic acid groups in the base polymer. Membranes cast from these materials were investigated in relation to proton conductivity and methanol permeability in the temperature range from 20°C to 60°C. It was found that both these properties increase as the polymer is increasingly sulfonated, with abrupt jumps occurring at a concentration of sulfonic acid groups of about 15 mol%. The most extensively sulfon...

  18. Synthesis in pilot plant scale and physical properties of sulfonated polystyrene

    OpenAIRE

    Martins, Cristiane R.; Ruggeri,Giacommo; Paoli,Marco-A. De

    2003-01-01

    The homogenous sulfonation of polystyrene was developed in a pilot plant scale producing polymers with different sulfonation degrees (18 to 22 mole % of sulfonated styrene units). The reaction yield depends chiefly on the concentration ratio of acetyl sulfate and polystyrene. The morphological and thermal properties of the sulfonated polystyrene obtained by homogeneous sulfonation were studied by means of scanning electron microscopy, differential scanning calorimetry and thermogravimetry. Th...

  19. Synthesis of Poly(phthalazinone ether ketone) Containing Sodium Sulfonate Groups via Direct Polymerization

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    1, 2-Dihydro-4-(4-hydroxyphenyl)(2H)phthalazin-1-one(DHPZ) was sulfonated in con- centrated sulfuric acid. Poly(phthalazinone ether ketone) containing pendant sodium sulfonate group was synthesized from sulfonated and pure 1,2-dihydro-4-(4-hydroxyphenyl)(2H)phthalazin- 1-one, and 4,4(-difluorodiphenylketone. The sulfonated monomer and sulfonated polymer were characterized with FT-IR and 1H-NMR.

  20. Tracer Diffusion of Polystyrene in Lightly Sulfonated Polystyrene

    Science.gov (United States)

    Xu, Chen; Zhou, Nancy; Burghardt, Wesley; Winey, Karen; Composto, Russell

    2005-03-01

    The tracer diffusion coefficient D^* of deuterated polystyrene (d-PS) (Mw = 65,900 g/mol) in lightly sulfonated polystyrene (P(S-SSx)) (Mw = 65,000 g/mol) as a function of sulfonation mole fraction (x) was measured by forward recoil spectrometry (FRES). For x sulfonation, according to D^* = Do exp(-0.14 Ns), where Ns is the number of sulfuric acid groups per chain. This slowing-down is attributed to an increase in the monomeric friction coefficient which increases with sulfonation. The diffusion mechanism includes both reptation and constraint release. The monomeric friction coefficient for d-PS in P(S-SSx) is compared with the coefficient for P(S-SSx) measured by rheology.

  1. Room temperature synthesis of biodiesel using sulfonated graphitic carbon nitride

    Science.gov (United States)

    Baig, R. B. Nasir; Verma, Sanny; Nadagouda, Mallikarjuna N.; Varma, Rajender S.

    2016-12-01

    Sulfonation of graphitic carbon nitride (g-CN) affords a polar and strongly acidic catalyst, Sg-CN, which displays unprecedented reactivity and selectivity in biodiesel synthesis and esterification reactions at room temperature.

  2. Room temperature synthesis of biodiesel using sulfonated graphitic carbon nitride

    Science.gov (United States)

    Sulfonation of graphitic carbon nitride (g-CN) affords a polar and strongly acidic catalyst, Sg-CN, which displays unprecedented reactivity and selectivity in biodiesel synthesis and esterification reactions at room temperature.

  3. Affinity labelling enzymes with esters of aromatic sulfonic acids

    Science.gov (United States)

    Wong, Show-Chu; Shaw, Elliott

    1977-01-01

    Novel esters of aromatic sulfonic acids are disclosed. The specific esters are nitrophenyl p- and m-amidinophenylmethanesulfonate. Also disclosed is a method for specific inactivation of the enzyme, thrombin, employing nitrophenyl p-amidinophenylmethanesulfonate.

  4. Sulfonated hydrocarbon graft architectures for cation exchange membranes

    DEFF Research Database (Denmark)

    Nielsen, Mads Møller; Jankova Atanasova, Katja; Hvilsted, Søren

    2013-01-01

    A synthetic strategy to hydrocarbon graft architectures prepared from a commercial polysulfone and aimed as ion exchange membrane material is proposed. Polystyrene is grafted from a polysulfone macroinitiator by atom transfer radical polymerization, and subsequently sulfonated with acetyl sulfate...

  5. Oil recovery with vinyl sulfonic acid-acrylamide copolymers

    Energy Technology Data Exchange (ETDEWEB)

    Norton, C.J.; Falk, D.O.

    1973-12-18

    An aqueous polymer flood containing sulfomethylated alkali metal vinyl sulfonate-acrylamide copolymers was proposed for use in secondary or tertiary enhanced oil recovery. The sulfonate groups on the copolymers sustain the viscosity of the flood in the presence of brine and lime. Injection of the copolymer solution into a waterflooded Berea core, produced 30.5 percent of the residual oil. It is preferred that the copolymers are partially hydrolyzed.

  6. The Snail-Induced Sulfonation Pathway in Breast Cancer Metastasis

    Science.gov (United States)

    2014-09-01

    AD_________________ Award Number: W81XWH-11-1-0494   TITLE: The Snail -Induced Sulfonation... Snail -Induced Sulfonation Pathway in Breast Cancer Metastasis 5b. GRANT NUMBER W81XWH-11-1-0494 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Dr...provided funding for a 3-year project that has resulted in fundamental new insights into how the transcription factor Snail can control gene

  7. Synthesis and Water Uptake of Sulfonated Poly (phthalazinone ether sulfone ketone)/Polyacrylic Acid Proton Exchange Membranes

    Institute of Scientific and Technical Information of China (English)

    Xue Mei WU; Gao Hong HE; Lin GAO; Shuang GU; Zheng Wen HU; Ping Jing YAO

    2006-01-01

    Novel SPPESK/PAA composite proton exchange membranes with semi-interpenetrating polymer network (sIPN) structure have been synthesized through the in-situ polymerization of acrylic acid (AA) in the presence of sulfonated poly (phthalazinone ether sulfone ketone) (SPPESK). The composite membranes were identified by FT-IR analysis. Water uptake of the composite membranes was as high as 89.7% at 90℃, nearly one time higher than that of the corresponding SPPESK membrane.

  8. Multiblock copolymers with highly sulfonated blocks containing di- and tetrasulfonated arylene sulfone segments for proton exchange membrane fuel cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Takamuku, Shogo; Jannasch, Patric [Polymer and Materials Chemistry, Department of Chemistry, Lund University (Sweden)

    2012-01-15

    Multiblock copoly(arylene ether sulfone)s with different block lengths and ionic contents are tailored for durable and proton-conducting electrolyte membranes. Two series of fully aromatic copolymers are prepared by coupling reactions between non-sulfonated hydrophobic precursor blocks and highly sulfonated hydrophilic precursor blocks containing either fully disulfonated diarylsulfone or fully tetrasulfonated tetraaryldisulfone segments. The sulfonic acid groups are exclusively introduced in ortho positions to the sulfone bridges to impede desulfonation reactions and give the blocks ion exchange capacities (IECs) of 4.1 and 4.6 meq. g{sup -1}, respectively. Solvent cast block copolymer membranes show well-connected hydrophilic nanophase domains for proton transport and high decomposition temperatures above 310 C under air. Despite higher IEC values, membranes containing tetrasulfonated tetraaryldisulfone segments display a markedly lower water uptake than the corresponding ones with disulfonated diarylsulfone segments when immersed in water at 100 C, presumably because of the much higher chain stiffness and glass transition temperature of the former segments. The former membranes have proton conductivities in level of a perfluorosulfonic acid membrane (NRE212) under fully humidified conditions. A membrane with an IEC of 1.83 meq. g{sup -1} reaches above 6 mS cm{sup -1} under 30% relative humidity at 80 C, to be compared with 10 mS cm{sup -1} for NRE212 under the same conditions. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  9. Ion Exchange Formation via Sulfonated Bicomponent Nonwovens

    Science.gov (United States)

    Stoughton, Hannah L.

    For many years ion exchange resins were used to: remove heavy metals from water, recover materials from wastewater, and eliminate harmful gases from the air. While use of these resin beads dominates the ion exchange industry, the beads have limitations that should be considered when decisions are made to employ them. For instance, officials must balance the inherent zero sum surface area and porosity of the materials. This series of studies investigates the use of bicomponent nonwovens as a base substrate for producing high surface area ion exchange materials for the removal of heavy metal ions. Functionalized materials were produced in a two-step process: (1) PET/PE spunbond bicomponent fibers were fractured completely, producing the high surface area nonwoven to be used as the base ion exchange material, and (2) the conditions for functionalizing the PET fibers of the nonwoven webs were investigated where an epoxy containing monomer was grafted to the surface followed by sulfonation of the monomer. The functionalization reactions of the PET fibers were monitored based on: weight gain, FTIR, TOF-SIMS, and SEM. Ion exchange properties were evaluated using titration and copper ion removal capacity from test solutions. The relationship between web structure and removal efficiency of the metal ions was defined through a comparison of the bicomponent and homocomponent nonwovens for copper ion removal efficiency. The investigation revealed that utilizing the high surface area, fractured bicomponent nonwoven ion exchange materials with capacities comparable to commercially available ion exchange resins could be produced.

  10. Fibronectin fibrillogenesis on sulfonated polystyrene surfaces.

    Science.gov (United States)

    Pernodet, Nadine; Rafailovich, Miriam; Sokolov, Jonathan; Xu, D; Yang, Nan-Loh; McLeod, Kenneth

    2003-03-15

    Extracellular matrix (ECM) protein adsorption and organization serves as a critical first step in the development and organization of tissues. Advances in tissue engineering, therefore, will depend on the ability to control the rate and pattern of ECM formation. Fibronectin is a prominent component of the ECM, which undergoes fibrillogenesis in the presence of cells. Using sulfonated polysyrene surfaces, we showed that fibronectin undergoes a transition from monolayer to multilayer adsorption at calculated surface charge densities above 0.03 Coulombs (C)/m(2). At charge densities above approximately 0.08 C/m(2), distinct fibronectin fibrillar networks are observed to form with a fibril morphology similar to those observed to form in situ on cell surfaces. This self-organization process is time dependent, with the fibrils achieving dimensions of 30-40 microm in length and 1 microm in height after 72 h of incubation. We suggest that the polarization of charge domains on the polyampholytic fibronectin molecules near high charge density surfaces is sufficient to initiate the multilayer adsorption and the organization of these fibrillar structures. These results suggest that the nonlinear dependence of adsorption on surface charge density may play an important role in the self-organization of many matrix components.

  11. Nanoscale Morphology of Sulfonated Polystyrene Ionomers

    Science.gov (United States)

    Zhou, Nancy C.; Winey, Karen I.

    2007-03-01

    We have applied our scanning transmission electron microscopy (STEM) methods to investigate the size, shape and spatial distribution of the ionic, nanoscale aggregates in poly(styrene-ran-styrene sulfonate) (P(S-SSx)) ionomers. This analytical electron microscopy method minimizes phase contrast that can obscure nano-scale features and accentuates differences in atomic number. We recently reported quantitative agreement between STEM and X-ray scattering results in a Cu-neutralized poly(styrene-ran-methacrylic acid) (SMAA) ionomer with respect to the size of the ionic aggregates and their number density. For this study, P(S-SSx) ionomers were prepared by solution neutralizing with metal acetates, solution casting, and annealing. Initial STEM results from P(S-SS0.019) fully neutralized with Zn indicate a uniform distribution of monodisperse spherical aggregates. Combining direct imaging and X-ray scattering of P(S-SSx) ionomers, we will investigate the effect of cation type and level of neutralization.

  12. Perfluoroalkyl sulfonates cause alkyl chain length-dependent hepatic steatosis and hypolipidemia mainly by impairing lipoprotein production in APOE*3-leiden CETP mice

    NARCIS (Netherlands)

    Bijland, S.; Rensen, P.C.N.; Pieterman, E.J.; Maas, A.C.E.; Hoorn, J.W. van der; Erk, M.J. van; Havekes, L.M.; Dijk, K.W. van; Chang, S.C.; Ehresman, D.J.; Butenhoff, J.L.; Princen, H.M.G.

    2011-01-01

    Perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), and perfluorooctane sulfonate (PFOS) are stable perfluoroalkyl sulfonate (PFAS) surfactants, and PFHxS and PFOS are frequently detected in human biomonitoring studies. Some epidemiological studies have shown modest positive correla

  13. Miscibility of Polystyrene and Lighted Sulfonated Polystyrene Blends

    Science.gov (United States)

    Zhou, N. C.; Burghardt, W. R.; Composto, R. J.

    2005-03-01

    The blend miscibility of deuterated polystyrene (dPS) and lighted sulfonated poly(styrene-ran-sulfonated polystyrene) (P (S-SS)) has been examined by forward recoil spectrometry (FRES). Equilibrium coexistence compositions were determined for dPS:P(S-SSx) blends where x is the mole percent of sulfonation.At x = 0.2%, the blends are fully miscible at 150°C to 190°C, while at x = 2.6% the system fully immiscible at the same temperatures. Intermediate levels of sulfonation (0.7, 1.0 and 1.2%) are partially miscible and exhibit an upper critical solution temperature (UCST). This behavior is attributed to the dilution of repulsive intra-molecular interaction between the ionic and non-ionic groups in the copolymer due to favorable interactions with the non-ionic group of the homopolymer PS. Estimates using the Flory-Huggins and the copolymer effect theories found a large ( 20) positive monomer-monomer interaction parameter between styrene and styrene sulfonate. This large interaction parameter might drive phase separation within a compositionally disperse random copolymers sample.

  14. Julia Olefination as a General Route to Phenyl (alpha-Fluoro)vinyl Sulfones.

    Science.gov (United States)

    He, Maggie; Ghosh, Arun K; Zajc, Barbara

    2008-04-01

    Mild and efficient synthesis of phenyl (alpha-fluoro)vinyl sulfones via condensation of aldehydes and a ketone with a novel benzothiazolyl based bis-sulfone reagent is reported and this proceeds with moderate to good Z-stereoselectivity.

  15. Dynamics of Sulfonated Polystyrene Ionomers by Dielectric Relaxation Spectroscopy

    Science.gov (United States)

    Castagna, Alicia; Wang, Wenqin; Winey, Karen; Runt, James

    2010-03-01

    Broadband dielectric spectroscopy was used to investigate the dynamics of sulfonated polystyrene (SPS) ionomers, in both the acid and neutralized form. This study seeks to elucidate the role of counter ion type (Zn, Na, and Cs), degree of sulfonation (9 and 6%), and ion cluster morphology on the relaxation phenomena of SPS. Degree of neutralization and ion type have been found to significantly impact the breadth and time scale of the segmental relaxation process. High temperature relaxation processes, tentatively proposed to arise from Maxwell-Wagner-Sillars interfacial polarization and a hydrogen bonding relaxation, have also been identified. Bands in the sulfonate stretching region of FTIR spectra reveal information about ion coordination in the local aggregate environment. A combination of scanning transmission electron microscopy imaging and X-ray scattering confirmed the presence of homogeneously distributed, nearly monodisperse spherical ionic aggregates in the polymer matrix.

  16. Surface Sulfonation of Polyvinyl Chloride by Plasma for Antithrombogenicity

    Institute of Scientific and Technical Information of China (English)

    刘鹏; 陈亚芍

    2004-01-01

    To enhance the blood compatibility of Polyvinyl Chloride (PVC) film, the film was modified by SO2/O2 gas plasma treatment. The effect of surface sulfonation of PVC treated by various SO2/O2 gas plasma depended on the volume ratio O2/(SO2 + 02). When the volumeratio was 0.5, the effect of sulfonation was the best. Sulfonic acid groups were specifically and efficiently introduced onto the PVC surface, which was proved by X-ray photoelectron spectroscopy (XPS) and Attenuated Total Reflectance Fourier Transfer Infrared (ATR-FTIR) spectroscopy. The surface microstructure of modified PVC film was studied with scanning electron microscopy (SEM).The antithrombogenicity of the samples was determined by the activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT) and plasma recalcification time (PRT)tests and platelet adhesion experiment. The results indicated that the antithrombogenicity of modified PVC was improved remarkably.

  17. Phase Behavior and Structural Transitions in Sodium Dodecyl Sulfonate Microemulsions

    Institute of Scientific and Technical Information of China (English)

    杨根生; 施介华; 等

    2002-01-01

    The forming mechanism of microemulsion of sodium dodecyl sulfonate.alcohols,water and isooctane was studied,with particular emphasis on the effect of molecular weight and concentration of alocohols.Phase diagram of the four components,alcohol, sodium dodecyl sulfonate,water and isooctane,was used as a means of study,through which the microemulsion regions were determined.Phase diagram of sodium dodecyl sulfonate/n-pentanol/isooctane/water system at km=2(km=Wn-pentanol/WSDS)is presented. The variation of conductivities of different microemulsion samples with water was measured.From the conductivities we investigated a change in structure from water droplets in oil(W/O)at low water content to liquid crystal at intermediate water content and a structure of oil droplets in water(O/W)at high water content.

  18. Miscibility of Methylmethacrylate-co-methacrylic Acid Polymer with Magnesium, Zinc, and Manganese Sulfonated Polystyrene Ionomers

    OpenAIRE

    ALKAN, Cemil; YURTSEVEN, Nebahat; ARAS, Leyla

    2005-01-01

    The miscibility of methyl methacrylate-co-methacrylic acid polymer (MMA-MAA) with metal neutralized sulfonated polystyrene ionomers was investigated by viscometry, differential scanning calorimetry (DSC), and Fourier transform infrared radiation spectroscopy (FTIR) techniques. Polystyrene (PS) was sulfonated by acetic anhydride and sulfuric acid and the sulfonation degree was found to be 2.6 mole percent, and 2.6 mole percent sulfonated polystyrene was neutralized by Mg, Zn, and Mn sa...

  19. Conjugate Additions of Secondary Amines and Water to Allenyl Perfluoroalkyl Sulfones

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-Jin; LIN Yun; LIU Jin-Tao

    2006-01-01

    Preparation of allenyl perfluoroalkyl sulfones from perfluoroalkyl sulfinyl chlorides and their reactions with secondary amines and water were studied. At room temperature secondary amines reacted readily with allenyl perfluoroalkyl sulfones to give the corresponding enamine adducts, which underwent rearrangement to afford conjugate enamines in refluxing toluene. Good diastereoslectivities were observed in the addition of diethylamine to γ-ethyl-γ-methylallenyl perfluoroalkyl sulfones. In refluxing acetonitrile, water could also undergo the similar addition with allenyl perfluoroalkyl sulfones.

  20. Ruthenium-catalyzed meta sulfonation of 2-phenylpyridines.

    Science.gov (United States)

    Saidi, Ourida; Marafie, Jameel; Ledger, Araminta E W; Liu, Po Man; Mahon, Mary F; Kociok-Köhn, Gabriele; Whittlesey, Michael K; Frost, Christopher G

    2011-12-07

    A selective catalytic meta sulfonation of 2-phenylpyridines was found to occur in the presence of (arene)ruthenium(II) complexes upon reaction with sulfonyl chlorides. The 2-pyridyl group facilitates the formation of a stable Ru-C(aryl) σ bond that induces a strong para-directing effect. Electrophilic aromatic substitution proceeds with the sulfonyl chloride to furnish a sulfone at the position meta to the chelating group. This new catalytic process offers access to atypical regioselectivity for reactions involving chelation-assisted cyclometalation.

  1. 40 CFR 721.5425 - α-Olefin sulfonate, potassium salts.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false α-Olefin sulfonate, potassium salts... Substances § 721.5425 α-Olefin sulfonate, potassium salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as an α-olefin sulfonate, potassium salt...

  2. Survey of sulfonated polyimide membrane as a good candidate for nafion substitution in fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Akbarian-Feizi, Leila; Mehdipour-Ataei, Shahram; Yeganeh, Hamid [Iran Polymer and Petrochemical Institute, P.O. Box 14965/115, Tehran (Iran)

    2010-09-15

    Studies in fuel cell membranes show that modification of polyimides by introduction of aliphatic linkages in the structure of sulfonated copolyimides, synthesis of branched/crosslinked sulfonated polyimides, and semi and fully interpenetrating polymer networks of sulfonated polyimides restrain suitable potential for Nafion substitution. (author)

  3. Chemical Agent Performance of Sulfonated Ionomeric Membranes for Chem/Bio Applications

    Science.gov (United States)

    2008-12-01

    Polyisobutylene ( PIB ) Chemically Modified IB Sulfonic Acid Counter-ion (Ba, Mg, Ca, Zn, Cs)Block Copolymer Morphology Sulfonic acid...Mauritz, K., 2000: Diffusion of Alcohols Through Sulfonated PS/ PIB /PS Block Copolymers Using FTIR-ATR Spectroscopy, Polymer Materials: Engineering

  4. 40 CFR 721.5450 - α-Olefin sulfonate, sodium salt.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false α-Olefin sulfonate, sodium salt. 721... Substances § 721.5450 α-Olefin sulfonate, sodium salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as α-olefin sulfonate, sodium...

  5. 40 CFR 721.9620 - Aromatic sulfonic acid compound with amine.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Aromatic sulfonic acid compound with... Specific Chemical Substances § 721.9620 Aromatic sulfonic acid compound with amine. (a) Chemical substance... aromatic sulfonic acid compound with amine (PMN P-93-832) is subject to reporting under this section...

  6. Blending of styrene-block-butadiene-block-styrene copolymer with sulfonated vinyl aromatic polymers

    NARCIS (Netherlands)

    Ruggeri, Giacomo; Passaglia, Elisa; Giorgi, Ivan; Picchioni, Francesco; Aglietto, Mauro

    2001-01-01

    Different polymers containing sulfonic groups attached to the phenyl rings were prepared by sulfonation of polystyrene (PS) and styrene-block-(ethylene-co-1-butene)-block-styrene (SEBS). The sulfonation degree (SD) was varied between 1 and 20 mol% of the styrene units. Polyphase materials containing

  7. Phase behavior of a pure alkyl aryl sulfonate surfactant. [Sodium 8-phenyl-n-hexadecyl-p-sulfonate

    Energy Technology Data Exchange (ETDEWEB)

    Franses, E.I.; Davis, H.T.; Miller, W.G.; Scriven, L.E.

    1978-03-01

    Specctroturbidimetry, visual and microscopic observations, ultracentrifugation and ultrafiltration, conductimetry, and /sup 13/C NMR were used to study the phase behavior of pure sodium 8-phenyl-n-hexadecyl-p-sulfonate in water--NaCl, decane, and water--decane. Solubility of the sulfonate in water is 0.06 wt % at 25/sup 0/C and 0.7 wt % at 90/sup 0/C, and it drops to 0.0002 wt % in 3 wt % NaCl (25/sup 0/C). A liquid crystalline phase in equilibrium with aqueous solution contains 25 wt % water. Nucleation of supersaturated solutions is slow. Dispersability of the sulfonate is high, but NaCl has an adverse effect. 39 references, 13 figs., 5 tables. (DLC)

  8. Molecular dynamics simulation of diffusion coefficients and structural properties of some alkylbenzenes in supercritical carbon dioxide at infinite dilution.

    Science.gov (United States)

    Wang, Jinyang; Zhong, Haimin; Feng, Huajie; Qiu, Wenda; Chen, Liuping

    2014-03-14

    The binary infinite dilute diffusion coefficients, D₁₂(∞), of some alkylbenzenes (Ph-C(n), from Ph-H to Ph-C12) from 313 K to 333 K at 15 MPa in supercritical carbon dioxide (scCO2) have been studied by molecular dynamics (MD) simulation. The MD values agree well with the experimental ones, which indicate MD simulation technique is a powerful way to predict and obtain diffusion coefficients of solutes in supercritical fluids. Besides, the local structures of Ph-C(n)/CO2 fluids are further investigated by calculating radial distribution functions and coordination numbers. It qualitatively convinces that the first solvation shell of Ph-C(n) in scCO2 is significantly influenced by the structure of Ph-C(n) solute. Meanwhile, the mean end-to-end distance, the mean radius of gyration and dihedral angle distribution are calculated to gain an insight into the structural properties of Ph-C(n) in scCO2. The abnormal trends of radial distribution functions and coordination numbers can be reasonably explained in term of molecular flexibility. Moreover, the computed results of dihedral angle clarify that flexibility of long-chain Ph-C(n) is the result of internal rotation of C-C single bond (σ(c-c)) in alkyl chain. It is interesting that compared with n-alkane, because of the existence of benzene ring, the flexibility of alkyl chain in Ph-C(n) with same carbon atom number is significantly reduced, as a result, the carbon chain dependence of diffusion behaviors for long-chain n-alkane (n ≥ 5) and long-chain Ph-C(n) (n ≥ 4) in scCO2 are different.

  9. Future LAB feedstocks:the advent of pearl GTL%未来的烷基苯原料:天然气液化油

    Institute of Scientific and Technical Information of China (English)

    刘晓臣

    2016-01-01

    采用两种不同来源的正构烷烃合成了相应的烷基苯,经磺化、中和后得到两种烷基苯磺酸盐,测定了其应用性能,评价了其对环境的影响。结果发现,来源于天然气液化油(GTL)的正构烷烃完全可以替代来源于煤油的正构烷烃生产烷基苯及其磺酸盐。%Two kinds of normal parafifn were used to synthesize their corresponding linear alkylbenzene, followed by sulfonation and neutralization to obtain linear alkylbenzene sulfonate (LAS). The properties of LAS were measured to investigate their applications and impact on environment. Results showed that the normal parafifn obtained from kerosene could be replaced by that of Pearl Gas to Liquids (GTL) to prepare linear alkylbenzene and alkylbenzene sulfonate.

  10. Amperometric urea biosensors based on sulfonated graphene/polyaniline nanocomposite

    Directory of Open Access Journals (Sweden)

    Das G

    2015-08-01

    Full Text Available Gautam Das, Hyon Hee Yoon Department of Chemical and Biological Engineering, Gachon University, Seongnam, Gyeonggi-do, South Korea Abstract: An electrochemical biosensor based on sulfonated graphene/polyaniline nanocomposite was developed for urea analysis. Oxidative polymerization of aniline in the presence of sulfonated graphene oxide was carried out by electrochemical methods in an aqueous environment. The structural properties of the nanocomposite were characterized by Fourier-transform infrared, Raman spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy techniques. The urease enzyme-immobilized sulfonated graphene/polyaniline nanocomposite film showed impressive performance in the electroanalytical detection of urea with a detection limit of 0.050 mM and a sensitivity of 0.85 µA·cm-2·mM-1. The biosensor achieved a broad linear range of detection (0.12–12.3 mM with a notable response time of approximately 5 seconds. Moreover, the fabricated biosensor retained 81% of its initial activity (based on sensitivity after 15 days of storage at 4°C. The ease of fabrication coupled with the low cost and good electrochemical performance of this system holds potential for the development of solid-state biosensors for urea detection. Keywords: electrochemical deposition, sulfonated graphene oxide, urease

  11. Wetting behavior of lightly sulfonated polystyrene ionomers on silica surfaces.

    Science.gov (United States)

    Zhai, Xiaowen; Weiss, R A

    2008-11-18

    The wetting/dewetting behavior of thin films of lightly sulfonated low molecular weight polystyrene (SPS) ionomers spin-coated onto silica surfaces were studied using atomic force microscopy (AFM), contact angle measurements, and electron microscopy. The effects of the sulfonation level, the choice of the cation, the solvent used to spin-coat the films, and the molecular weight of the ionomer were investigated. Small angle X-ray scattering was used to determine the bulk microstructure of the films. The addition of the sulfonate groups suppressed the dewetting behavior of the PS above its glass transition temperature, e.g. no dewetting occurred even after 240 h of annealing at 120 degrees C. Increasing the sulfonation level led to more homogeneous and smoother surfaces. The choice of the cation used affected the wetting properties, but not in a predictable manner. When tetrahydrofuran (THF) or a THF/methanol mixed solvent was used for spin-casting, a submicron-textured surface morphology was produced, which may be a consequence of spinodal decomposition of the film surface during casting. Upon annealing for long times, the particles coalesced into a coherent, nonwetted film.

  12. Homolytic C-O cleavage in phosphates and sulfonates.

    Science.gov (United States)

    Ding, Lanlan; Zheng, Wenrui; Wang, Yingxing

    2015-04-09

    The C-O homolytic bond dissociation enthalpies(BDEs) were calculated by high-level ab initio including G4, G3B3, G3, CBS-QB3 and a series of density function theory (DFT) methods. It is found that the wB97 method gave the most reliable C-O BDEs and the root-mean-square deviation (RMSD) is 7.6 kJ/mol. Therefore, the C(sp(2))-O BDE predictions and the substituent effects of alkenyl phosphates/sulfonates and aryl phosphates/sulfonates were investigated in detail by using the wB97 method. Interestingly, there exist different substituent effects in α- and β-substituted alkenyl phosphates/sulfonates. Excellent linear relationships between the C-O BDEs of β-substituted alkenyl phosphates/sulfonates with substituent constant σp(+) were found. In addition, the NBO analysis further disclosed the essence of the substituent effects on C-O BDEs.

  13. Production of sulfonated cation-exchangers from petroleum asphaltites

    Energy Technology Data Exchange (ETDEWEB)

    Pokonova, Yu.V.; Pol' kin, G.B.; Proskuryakov, V.A.; Vinogradov, M.V.

    1982-02-10

    Continuing our studies of the preparation of products of practical value from asphaltite, a new by-product of oil refining, we obtained sulfonated cation-exchangers from a mixture of asphaltite and acid tar. It is shown that these cation-exchangers have good kinetic properties and are superior in thermal and thermohydrolytic stability to the commercial cation-exchange resin KU-2.

  14. Synthesis and properties of poly(sulfone-arylate) copolymers

    NARCIS (Netherlands)

    Stephen, Ranimol; Gibon, Cécile M.; Weber, Martin; Gaymans, Reinoud J.

    2009-01-01

    Poly(sulfone-arylate) was synthesized in a reaction between dihydroxy polysulfone prepolymers and either diphenyl terephthalate or terephthaloyl chloride. The dihydroxy polysulfone prepolymers had molecular weights of 2000 and 4000 g/mol. The polymerization with diphenyl terephthalate was carried ou

  15. Sulfonated polyimides containing triphenylphosphine oxide for proton exchange membranes

    Energy Technology Data Exchange (ETDEWEB)

    Mandal, Arun Kumar; Bera, Debaditya; Banerjee, Susanta, E-mail: susanta@matsc.iitkgp.ernet.in

    2016-09-15

    A series of sulfonated co-polyimides (co-SPI) were prepared by one pot polycondensation reaction of a combination of diamines namely; 4,4′-diaminostilbene-2,2′-disulfonic acid (DSDSA) and prepared non-sulfonated diamine (DATPPO) containing triphenylphosphine oxide with 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA). All these soluble co-SPI gave flexible membranes with high thermal stability and showed good mechanical property. Transmission electron microscopy (TEM) analysis revealed the microphase separated morphology with well-dispersed hydrophilic (cluster size in the range of 5–55 nm) domains. The co-SPI membranes showed high oxidative and hydrolytic stability with higher proton conductivity. All these co-SPI membranes exhibited low water uptake and swelling ratio. The co-SPI membrane TPPO-60 (60% degree of sulfonation) with IEC{sub W} = 1.84 mequiv g{sup −1} showed high proton conductivity (99 mS cm{sup −1} at 80 °C and 107 mS cm{sup −1} at 90 °C) in water with high oxidative (20 h) and hydrolytic stability (only 5% degradation in 24 h). - Highlights: • Triphenylphosphine oxide containing sulfonated polyimides (SPIs) was synthesized. • The SPIs showed good oxidative and hydrolytic stability and high proton conductivity. • TEM analysis revealed well separated morphology of the SPIs.

  16. Sodium dimercaptopropane sulfonate as antidote against non-metallic pesticides

    Institute of Scientific and Technical Information of China (English)

    Zhi-kang CHEN; Zhong-qiu LU

    2004-01-01

    @@ INTRODUCTION With the advent of World War II, dimercaptol was first developed in England as an effective antidote against arsenical agents. In 1950' s, scientists from the Soviet Union developed a water-soluble compound, sodium dimercaptopropane sulfonate (Na-DMPS) named as Unithiol (or Unitiol), which was able to chelate heavy metals and metalloids.

  17. Thermoanalytical Investigation of Some Sulfone-Containing Drugs

    OpenAIRE

    2012-01-01

    The thermal behavior of some sulfone-containing drugs, namely, dapsone (DDS), dimethylsulfone (MSM), and topiramate (TOP) in drug substances, and products were investigated using different thermal techniques. These include thermogravimetry (TGA), derivative thermogravimetry (DTG), differential thermal analysis (DTA), and differential scanning calorimetry (DSC). The thermogravimetric data allowed the determination of the kinetic parameters: activation energy (E a ), frequency factor (A), and r...

  18. Fate of linear alkylbenzenes and benzothiazoles of anthropogenic origin and their potential as environmental molecular markers in the Pearl River Delta, South China

    Energy Technology Data Exchange (ETDEWEB)

    Ni Honggang [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Graduate School, Chinese Academy of Sciences, Beijing 100049 (China); Shen Rulang [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Zeng Hui [Key Laboratory for Environmental and Urban Sciences, Shenzhen Graduate School, Peking University, Shenzhen 518055 (China); Zeng, Eddy Y., E-mail: eddyzeng@gig.ac.c [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

    2009-12-15

    The mass emissions of linear alkylbenzenes (LABs), benzothiazole (BT), and 2-[4-morpholinyl]benzothiazole (24MoBT) from anthropogenic activities within one year were estimated according to the population and the number of automobiles in the Pearl River Delta (PRD), South China. Based on the estimation, the distribution of these compounds among various environmental media was simulated with a mass balance box model established in the present study. The results showed that 79% of LABs generated in the PRD was stored in sediment while only 1.3% of LABs was presumably transported to the adjacent South China Sea (SCS). On the contrary, 47% of BT and 77% of 24MoBT generated in the region were carried with riverine runoff to the coastal ocean. The results from the present study suggest that hydrophobic compounds tend to stay in the watershed of the PRD, whereas hydrophilic ones mainly outflow to the coastal ocean. - A simple mass balance box model examines the fate of linear alkylbenzenes and benzothiazoles in the Pearl River Delta, South China.

  19. Phase equilibria study in binary systems (tetra-n-butylphosphonium tosylate ionic liquid + 1-alcohol, or benzene, or n-alkylbenzene).

    Science.gov (United States)

    Domańska, Urszula; Paduszyński, Kamil

    2008-09-04

    Ambient pressure (solid + liquid) equilibria (SLE) and (liquid + liquid) equilibria (LLE) of binary systems--ionic liquid (IL) tetra- n-butylphosphonium p-toluenesulfonate + 1-alcohol (1-butanol, 1-hexanol, 1-octanol, 1-decanol, or 1-dodecanol), benzene, or n-alkylbenzene (toluene, ethylbenzene, n-propylbenzene)-have been determined by using dynamic method in a broad range of mole fractions and temperatures from 250 to 335 K. For binaries containing alcohol, simple eutectic diagrams were observed with complete miscibility in the liquid phase. Only in the case of system [IL + n-propylbenzene] was mutual immiscibility with an upper critical solution temperature (UCST) with low solubility of the IL in the alcohol and high solubility of the alcohol in the IL detected. The basic thermal properties of pure IL, i.e., melting and glass-transition temperatures as well as enthalpy of melting, have been measured with differential scanning microcalorimetry technique (DSC). Well-known UNIQUAC, Wilson, NRTL, NRTL1, and NRTL2 equations have been fitted to obtain experimental data sets. For the system containing immiscibility gap [IL + n-propylbenzene], parameters of the equations have been derived only from SLE data. As a measure of goodness of correlations, root-mean square deviations of temperature have been used. These experimental results were compared to the previously measured binary systems with tetra- n-butylphosphonium methanesulfonate. Changing anion from methanesulfonate to p-toluenesulfonate decreases solubilities in systems with alcohols and increases the solubilities in binary systems with benzene and alkylbenzenes.

  20. Concrete Durability: A Multibillion-Dollar Opportunity

    Science.gov (United States)

    1987-01-01

    materials usually are sulfonated melamine formaldehyde condensates and sulfonated naphthalene formaldehyde condensates. The use of water-reducing...used in air-entraining additions and admixtures include alkylbenzene sulfonate , polyethylene oxide, detergents, and salts of fatty acids. Specifications

  1. Impact of model perfume molecules on the self-assembly of anionic surfactant sodium dodecyl 6-benzene sulfonate.

    Science.gov (United States)

    Bradbury, Robert; Penfold, Jeffrey; Thomas, Robert K; Tucker, Ian M; Petkov, Jordan T; Jones, Craig; Grillo, Isabelle

    2013-03-12

    The impact of two model perfumes with differing degrees of hydrophobicity/hydrophilicity, linalool (LL) and phenylethanol (PE), on the solution structure of anionic surfactant sodium dodecyl 6-benzene sulfonate, LAS-6, has been studied by small angle neutron scattering, SANS. For both types of perfume molecules, complex phase behavior is observed. The phase behavior depends upon the concentration, surfactant/perfume composition, and type of perfume. The more hydrophilic perfume PE promotes the formation of more highly curved structures. At relatively low surfactant concentrations, small globular micelles, L1, are formed. These become perfume droplets, L(sm), stabilized by the surfactant at much higher perfume solution compositions. At higher surfactant concentrations, the tendency of LAS-6 to form more planar structures is evident. The more hydrophobic linalool promotes the formation of more planar structures. Combined with the greater tendency of LAS-6 to form planar structures, this results in the planar structures dominating the phase behavior for the LAS-6/linalool mixtures. For the LAS-6/linalool mixture, the self-assembly is in the form of micelles only at the lowest surfactant and perfume concentrations. Over most of the concentration-composition space explored, the structures are predominantly lamellar, L(α), or vesicle, L(v), or in the form of a lamellar/micellar coexistence. At low and intermediate amounts of LL, a significantly different structure is observed, and the aggregates are in the form of small, relatively monodisperse vesicles (i.e., nanovesicles), L(sv).

  2. Isotopic Measurements of Organic Sulfonates From The Murchison Meteorite

    Science.gov (United States)

    Cooper, G. W.; Chang, S.; DeVincenzi, Donald L. (Technical Monitor)

    1995-01-01

    Organic sulfonates and phosphonates have been extracted from the Murchison meteorite for stable isotope measurements. Preliminary stable isotope measurements of individual alkyl sulfonates, R-SO3H (R=C(sub n)H(sub 2n+l)), are shown. These compounds were found in aqueous extracts of Murchison. Both groups show trends similar to other homologous series of organic compounds indigenous to Murchison. Molecular abundances decrease with increasing carbon number, and all possible isomers at each carbon number (through C-4) are present. Carbon isotope measurements of the sulfonates show a decrease in the C-13/C-12 ratio with increasing carbon number. The overall objectives of this project are to obtain dime element carbon, hydrogen, and sulfur - intramolecular isotopic analyses of individual sulfonates, and isotopic measurement of carbon and hydrogen of the phosphonates as a group. The Murchison meteorite is the best characterized carbonaceous chondrite with respect to organic chemistry. The finding of organic sulfonates and phosphonates in Murchison is of interest because they are the first well-characterized series of sulfur and phosphorus containing organic compounds found in meteorites. Also, meteorites, comets, and interplanetary dust particles may have been involved in chemical evolution on the early Earth. Because of the critical role of organic phosphorus and sulfur in all living systems, it is particularly interesting to see examples of abiotic syntheses of these classes of compounds. The study of the isotopic composition of the sulfonates and phosphonates can yield insight into their possible interstellar origin as well as their mechanisms of synthesis in the early solar system. Previous isotopic analyses of other classes of organic compounds indigenous to meteorites, e.g., amino acids, carboxylic acids, and hydrocarbons indicate the possibility that interstellar molecules were incorporated into meteorite parent bodies. In these compounds the ratios of heavy to

  3. 废水中的直链烷基苯磺酸钠的混凝气浮处理研究%Coagulation-flotation treatment of linear alkylbenzene sulfonate in waste water

    Institute of Scientific and Technical Information of China (English)

    夏红云; 贺敏

    2009-01-01

    研究了废水中的直链烷基苯磺酸钠混凝气浮处理的一些影响因素,包括pH、混凝剂(硫酸铝钾)用量、气浮时间,对比了混凝沉淀和混凝气浮处理直链烷基苯磺酸钠的处理效果.实验结果表明,pH、混凝剂用量及气浮时间均对混凝气浮处理效果有较大影响,当pH=6、混凝剂质量浓度为667 mg/L及气浮时间为5 min时,混凝气浮对直链烷基苯磺酸钠的去除率可达78.50%.

  4. Simultaneous Determination of 4 Kinds of Linear Alkylbenzene Sulfonates in Bun by SPE-HPLC%SPE-HPLC同时测定馒头中的4种直链烷基苯磺酸钠

    Institute of Scientific and Technical Information of China (English)

    贾松涛; 周围; 王波; 解迎双; 牛宏亮

    2011-01-01

    建立了馒头中4种直链烷基苯磺酸钠高效液相色谱的测定方法.样品经甲醇和水提取后经过MAX复合阴离子交换小柱净化后,利用高效液相色谱进行检测.方法检出限为5μg/mL,4种直链烷基苯磺酸钠的检测波长为225nm,回收率为84.92%-99.28%,相对标准偏差为4.37%-5.93%.可以满足馒头中直链烷基苯磺酸钠检测的方法要求.

  5. Las insulinas

    OpenAIRE

    Manuel González Ortiz; Esperanza Martínez Abundis

    2001-01-01

    La insulina es una hormona secretada por elpáncreas participa en el metabolismo de loscarbohidratos, lípidos y proteínas. La produc-ción deficiente de insulina y/o la disminución enla respuesta de los tejidos y órganos periféricosa su acción constituyen las principales basesetiopatogénicas de la diabetes mellitus. Lainsulina se ha podido sintetizar para su usofarmacológico y forma parte importante dentrode las opciones terapéuticas vigentes para elmanejo de la diabetes mellitus. La presente r...

  6. Dual-mode fluorescence switching induced by self-assembly of well-defined poly(arylene ether sulfone)s containing pyrene and amide moieties.

    Science.gov (United States)

    Park, Jeyoung; Kim, Jisung; Seo, Myungeun; Lee, Jinhee; Kim, Sang Youl

    2012-11-04

    A new class of fluorescent organogelators, pyrene-containing poly(arylene ether sulfone)s, showed two fluorescence switching modes in different gelation solvents. The THF gel exhibited excimer emission due to dimerization of the pyrene groups. In contrast, excimer emission was quenched after gelation in MC because of stacking among the pyrene groups.

  7. 二苯砜-3磺酸钾的合成及表征%SYNTHESIS AND CHARACTERIZATION OF POTASSIUM-DIPHENYL SULFONE SULFONATE

    Institute of Scientific and Technical Information of China (English)

    弋冰; 王德义; 李泽军

    2001-01-01

    Potassium-diphenyl sulfone sulfonate,a kind of effective flame retardant,was synthesized by two steps from benzene,benzenesulfony chloride and chlorosulfonic acid.The structure of the product was analyzed by MS,FT-IR and 1HNMR techniques.

  8. Las Sinapsis

    Directory of Open Access Journals (Sweden)

    Jorge Eduardo Duque Parra

    1997-12-01

    Full Text Available

    Introducción

    El estudio del sistema nervioso considera entre múltiples conexiones, aquéllas de carácter bioquímico que se median a través de sustancias elaboradas por las neuronas y que reciben la denominación de neurotransmisores’, dichas sustancias se vierten en las zonas de resquicio neuromuscular, neuroneuronal o neuroglandular, para modificar las condiciones de membrana y permitir la continuidad de los potenciales de acción (por creación de nuevos potenciales en las células subsiguientes, de la neurona hacia el órgano blanco.

    La integridad de los diversos elementos de la “zona de unión funcional” o sinapsis, asegura la adecuada comunicación entre el sistema nervioso y la mayoría de los elementos restantes del organismo humano.

    Las alteraciones de los elementos de las sinapsis, conllevan a la génesis de estados variables fisiológicos y patológicos somáticos, psicosomáticos o psíquicos, inconsecuentes con el estado de homeostasis.

    Las moléculas que se vierten en las hendiduras sinápticas, sirven, por tanto, de transductoras para efectos elementales (como los reflejos y en las estrategias complejas (como los de la actividad intelectual.

    Antecedentes

    Ya desde los tiempos de Galeno, se sabía que los nervios eran los responsables de la rápida comunicación entre el cuerpo y el cerebro; el estudio de las sinapsis nos remonta de manera indirecta a
    1791, fecha en la que Luigi Galvani, descubrió en sus experimentos con ancas de ranas, que entre los eventos eléctricos y los ocurridos en los nervios, existía una relación evidente (28,37,45’, los experimentos de Galvani se han refinado con el paso del tiempo, en nuestro siglo por ejemplo, el desarrollo del osciloscopio de rayos catódicos combinado con un amplificador potente, ha permitido medir las débiles y variables corrientes bioeléctricas de los

  9. Proton conductive membranes based on doped sulfonated polytriazole

    Energy Technology Data Exchange (ETDEWEB)

    Boaventura, M.; Brandao, L.; Mendes, A. [Laboratorio de Engenharia de Processos, Ambiente e Energia (LEPAE), Faculdade de Engenharia da Universidade do Porto, Rua Roberto Frias, 4200-465 Porto (Portugal); Ponce, M.L.; Nunes, S.P. [GKSS Research Centre Geesthacht GmbH, Max Planck Str. 1, D-21502, Geesthacht (Germany)

    2010-11-15

    This work reports the preparation and characterization of proton conducting sulfonated polytriazole membranes doped with three different agents: 1H-benzimidazole-2-sulfonic acid, benzimidazole and phosphoric acid. The modified membranes were characterized by scanning electron microscopy (SEM), infrared spectra, thermogravimetric analysis (TGA), dynamical mechanical thermal analysis (DMTA) and electrochemical impedance spectroscopy (EIS). The addition of doping agents resulted in a decrease of the glass transition temperature. For membranes doped with 85 wt.% phosphoric acid solution proton conductivity increased up to 2.10{sup -3} S cm{sup -1} at 120 C and at 5% relative humidity. The performance of the phosphoric acid doped membranes was evaluated in a fuel cell set-up at 120 C and 2.5% relative humidity. (author)

  10. Dynamics and Morphology of Sulfonated Polystyrene Ionomers by Dielectric Spectroscopy

    Science.gov (United States)

    Castagna, Alicia; Wang, Wenqin; Winey, Karen I.; Runt, James

    2009-03-01

    The dynamics of sulfonated polystyrene (SPS) ionomers, in both the acid and neutralized forms, were investigated using broadband dielectric spectroscopy. The influences of acid content, counterion type (Zn, Na and Cs), degree of neutralization, and microphase separated morphology on segmental and local dynamics, as well as on Maxwell -- Wagner -- Sillars interfacial polarization, were examined. Ionomers prepared from SPS containing 1.9 mol% sulfonic acid species exhibit a broader segmental process indicative of a considerably broader distribution of local environments, as compared to those in unneutralized SPS. Moreover, multiple segmental relaxations were identified in the dielectric spectra of Zn and Na neutralized SPS (1.9 mol%) ionomers, likely indicating two distinct environments arising from ion clustering. A combination of STEM imaging and X-ray scattering confirmed the presence of monodisperse spherical ionic aggregates that were homogeneously distributed in the polymer matrix.

  11. Sulfonated polystyrene fiber network-induced hybrid proton exchange membranes.

    Science.gov (United States)

    Yao, Yingfang; Ji, Liwen; Lin, Zhan; Li, Ying; Alcoutlabi, Mataz; Hamouda, Hechmi; Zhang, Xiangwu

    2011-09-01

    A novel type of hybrid membrane was fabricated by incorporating sulfonated polystyrene (S-PS) electrospun fibers into Nafion for the application in proton exchange membrane fuel cells. With the introduction of S-PS fiber mats, a large amount of sulfonic acid groups in Nafion aggregated onto the interfaces between S-PS fibers and the ionomer matrix, forming continuous pathways for facile proton transport. The resultant hybrid membranes had higher proton conductivities than that of recast Nafion, and the conductivities were controlled by selectively adjusting the fiber diameters. Consequently, hybrid membranes fabricated by ionomers, such as Nafion, incorporated with ionic-conducting nanofibers established a promising strategy for the rational design of high-performance proton exchange membranes.

  12. Preparation of sulfonated cation exchangers from petroleum asphaltites

    Energy Technology Data Exchange (ETDEWEB)

    Pokonova, Yu.V.; Pol' kin, G.B.; Proskuryakov, V.A.

    1980-01-01

    It was established that the reaction of petroleum asphaltite sulfonation is determined in the first step by the chemical reaction rate, and in the last --- by diffusion factors. The kinetic constants were found for each reaction step. Sulfonated cation exchangers were obtained having the characteristics: specific volume of the swollen cation exchanger 3.30 mL/g, bulk density of the air-dry product 0.58 g/mL., moisture content 23.4%, swelling in water 41.6%, mechanical strength 80.0%, static exchange capacity with respect to 0.1N NaOH solution 2.76 mg equiv/g, dynamic exchange capacity with respect to 0.0035N CaC1/sub 2/ solution for a specific load of 10 L/L.h 465 mg equiv/L.

  13. Permselectivity and conductivity of membranes based on sulfonated naphthalenic copolyimides.

    Science.gov (United States)

    Guo, Xiaoxia; Zhai, Fengxia; Fang, Jianhua; Laguna, Maria Fe; López-Gonzalez, Mar; Riande, Evaristo

    2007-12-13

    A series of sulfonated diamines were synthesized which were further used to obtain relevant sulfonated naphthalenic copolyimides. Tough and ductile membranes were cast from solutions of the copolyimides in dimethylsulfoxide, which exhibit high ion-exchange capacity and high water uptake. The protonic conductivity of the membranes equilibrated with water lies in the range 1.0-8.6 S/m, at 25 degrees C, being of the same order of magnitude as that reported for perfluorinated acidic membranes. The values of the transport number of protons and sodium ions are close to the unit for very dilute electrolyte solutions, but they lie in the range 0.80-0.90 for moderate concentrations. The membranes exhibit rather high electroosmotic permeability. The similarity of the diffusion coefficients of protons and water in the membranes suggests that the Grottus mechanism governs the protonic conductive process in the acidic membranes equilibrated with water.

  14. SULFONATED POLYIMIDES CONTAINING PYRIDINE GROUPS AS PROTON EXCHANGE MEMBRANE MATERIALS

    Institute of Scientific and Technical Information of China (English)

    Rui Lei; Chuan-qing Kang; Yun-jie Huang; Xue-peng Qiu; Xiang-ling Ji; Wei Xing; Lian-xun Gao

    2011-01-01

    A series of sulfonated polyimides (SPIs) containing pyridine groups were prepared by direct polycondensation from 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA),4,4′-diaminodiphenyl ether-2,2′-disulfonic acid (ODADS) and 4-(4-methoxy)phenyl-2,6-bis(4-aminophenyl)pyridine (DAM).The resulting copolymers displayed good solubility in common organic solvents.Flexible,transparent,tough membranes were obtained via solution casting.All the films showed high thermal stability with desulfonation temperature over 300℃.They exhibited prominent mechanical properties with Young's modulus around 2.0 GPa.High proton conductivity (0.23 S/em at 100% RH) was also observed.More importantly,the new materials exhibited low water uptake (30 wt%-75 wt% at 80℃) and improved water stability,which were attributed to the acid-base interaction between sulfonic acid and pyridine functional groups.

  15. Mortar modified with sulfonated polystyrene produced from waste plastic cups

    Directory of Open Access Journals (Sweden)

    L. A. C. MOTTA

    Full Text Available Abstract In this work, we studied the addition of sulfonated polystyrene produced from waste plastic cups as an admixture for mortars. Mortars were analyzed with polystyrene content of 0.0; 0.2; 0.6; 1.0 and 1.4% in relation to the cement mass. The influence of polystyrene on the mortars' properties was evaluated by the consistency index, water retention, water absorption, porosity, elasticity modulus, compressive strength, flexural strength, bond tensile strength and microscopy. The increase in the sulfonated polystyrene content decreased the elasticity modulus of the mortar and, despite higher porosity, there was a reduction of water absorption by capillarity. In relation to mortar without admixture, the modified mortar showed an increase in water retention and consistency index, and a large increase in flexural strength and bond tensile strength. The significant increase of bond tensile strength (214% with admixture 1% highlights the potential of the produced material as an adhesive mortar.

  16. New Fluorinated and Sulfonated Block Copolymers Final Report

    Science.gov (United States)

    2009-04-23

    serves as a plasticizer even in the hydrophobic FI domain. Similar glass transition reduction effects observed in other ionomer systems have been...Sulfonated Ionomer : Thermal Annealing and Solvent Effects.” American Physical Society National Meeting. Los Angeles, CA. March 21, 2005. 4. Akinbode...optimizing morphology and ultimately properties, membranes have been cast from relatively inexpensive block-copolymer ionomers of fluorinated poly

  17. Regioselective synthesis of chiral dimethyl-bis(ethylenedithiotetrathiafulvalene sulfones

    Directory of Open Access Journals (Sweden)

    Flavia Pop

    2015-07-01

    Full Text Available Enantiopure (R,R and (S,S-dimethyl-bis(ethylenedithiotetrathiafulvalene monosulfones have been synthesized by the aerial oxidation of the chiral dithiolates generated from the propionitrile-protected precursors. Both enantiomers crystallize in the orthorhombic chiral space group P212121. They show a boat-type conformation of the TTF moiety, a rather rigid dithiin sulfone ring and the methyl groups in a bisequatorial conformation. Cyclic voltammetry measurements indicate fully reversible oxidation in radical cation and dication species.

  18. Thermally stimulated depolarization current studies of sulfonated polystyrene ionomers

    Science.gov (United States)

    Carvalho, Antonio José Felix; Viana, Vicente Galber Freitas; Faria, Roberto Mendonça

    2009-12-01

    A detailed study of thermally stimulated depolarization current (TSDC) was carried out to investigate dipolar relaxation and the charge storage phenomenon in films of sulfonated polystyrene (SPS) ionomers having lithium or potassium as counterions. Differential scanning calorimetry measurements were also applied as a complementary technique, mainly to follow the change of the glass transition temperature with the amount of sulfonated groups. It was observed that, since the glass transition does not change significantly with the amount of sulfonated groups, a cluster of multiplets is expected not to be formed in the range used in this work. TSDC of SPS samples polarized at temperatures higher than the glass transition temperature showed three peaks: one at lower temperature (peak β), an intermediate peak (peak α), and a third that appeared at a temperature coincident with the polarization temperature (peak ρ). Quantitative information about trapping-detrapping and dipolar relaxation and their corresponding activation energies was determined by fittings of the deconvoluted peaks with kinetic relaxation processes.

  19. Thermally stimulated depolarization current studies of sulfonated polystyrene ionomers

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Antonio Jose Felix [Universidade Federal de Sao Carlos, Laboratory of Polymers and Renewable Materials, Sorocaba, SP (Brazil); Viana, Vicente Galber Freitas [Universidade Federal do Piaui, Centro de Ciencias da Natureza, Teresina, PI (Brazil); Faria, Roberto Mendonca [USP, Instituto de Fisica de Sao Carlos, SP (Brazil)

    2009-12-15

    A detailed study of thermally stimulated depolarization current (TSDC) was carried out to investigate dipolar relaxation and the charge storage phenomenon in films of sulfonated polystyrene (SPS) ionomers having lithium or potassium as counterions. Differential scanning calorimetry measurements were also applied as a complementary technique, mainly to follow the change of the glass transition temperature with the amount of sulfonated groups. It was observed that, since the glass transition does not change significantly with the amount of sulfonated groups, a cluster of multiplets is expected not to be formed in the range used in this work. TSDC of SPS samples polarized at temperatures higher than the glass transition temperature showed three peaks: one at lower temperature (peak {beta}), an intermediate peak (peak {alpha}), and a third that appeared at a temperature coincident with the polarization temperature (peak {rho}). Quantitative information about trapping-detrapping and dipolar relaxation and their corresponding activation energies was determined by fittings of the deconvoluted peaks with kinetic relaxation processes. (orig.)

  20. Composite plasma polymerized sulfonated polystyrene membrane for PEMFC

    Energy Technology Data Exchange (ETDEWEB)

    Nath, Bhabesh Kumar; Khan, Aziz; Chutia, Joyanti, E-mail: jchutiaiasst@gmail.com

    2015-10-15

    Highlights: • Methyl methane sulfonate (MMS) is used as the sulfonating agent. • The proton conductivity of the membrane is found to be 0.141 S cm{sup −1}. • Power density of fuel cell with styrene/MMS membrane is 0.5 W cm{sup −2}. • The membrane exhibits thermal stability up to 140 °C. - Abstract: This work presents the introduction of an organic compound methyl methane sulfonate (MMS) for the first time in fabrication of polystyrene based proton exchange membrane (PEM) by plasma polymerization process. The membrane is fabricated by co-polymerizing styrene and MMS in capacitively coupled continuous RF plasma. The chemical composition of the plasma polymerized polymer membrane is investigated using Fourier Transform Infrared Spectroscopy which reveals the formation of composite structure of styrene and MMS. The surface morphology studied using AFM and SEM depicts the effect of higher partial pressure of MMS on surface topography of the membrane. The proton transport property of the membrane studied using electrochemical impedance spectroscopy shows the achievement of maximum proton conductivity of 0.141 S cm{sup −1} which is comparable to Nafion 117 membrane. Fuel cell performance test of the synthesized membrane shows a maximum power density of 500 mW cm{sup −2} and current density of 0.62 A cm{sup −2} at 0.6 V.

  1. Amperometric urea biosensors based on sulfonated graphene/polyaniline nanocomposite.

    Science.gov (United States)

    Das, Gautam; Yoon, Hyon Hee

    2015-01-01

    An electrochemical biosensor based on sulfonated graphene/polyaniline nanocomposite was developed for urea analysis. Oxidative polymerization of aniline in the presence of sulfonated graphene oxide was carried out by electrochemical methods in an aqueous environment. The structural properties of the nanocomposite were characterized by Fourier-transform infrared, Raman spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy techniques. The urease enzyme-immobilized sulfonated graphene/polyaniline nanocomposite film showed impressive performance in the electroanalytical detection of urea with a detection limit of 0.050 mM and a sensitivity of 0.85 (μA · cm(-2)·mM(-1). The biosensor achieved a broad linear range of detection (0.12-12.3 mM) with a notable response time of approximately 5 seconds. Moreover, the fabricated biosensor retained 81% of its initial activity (based on sensitivity) after 15 days of storage at 4°C. The ease of fabrication coupled with the low cost and good electrochemical performance of this system holds potential for the development of solid-state biosensors for urea detection.

  2. Amperometric urea biosensors based on sulfonated graphene/polyaniline nanocomposite

    Science.gov (United States)

    Das, Gautam; Yoon, Hyon Hee

    2015-01-01

    An electrochemical biosensor based on sulfonated graphene/polyaniline nanocomposite was developed for urea analysis. Oxidative polymerization of aniline in the presence of sulfonated graphene oxide was carried out by electrochemical methods in an aqueous environment. The structural properties of the nanocomposite were characterized by Fourier-transform infrared, Raman spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy techniques. The urease enzyme-immobilized sulfonated graphene/polyaniline nanocomposite film showed impressive performance in the electroanalytical detection of urea with a detection limit of 0.050 mM and a sensitivity of 0.85 (μA · cm−2·mM−1. The biosensor achieved a broad linear range of detection (0.12–12.3 mM) with a notable response time of approximately 5 seconds. Moreover, the fabricated biosensor retained 81% of its initial activity (based on sensitivity) after 15 days of storage at 4°C. The ease of fabrication coupled with the low cost and good electrochemical performance of this system holds potential for the development of solid-state biosensors for urea detection. PMID:26346240

  3. Sulfonate-containing Copolymers Prepared by Semi-Continuous Emulsion Copolymerizaiton of Styrene and Sodium Styrene Sulfonate

    Institute of Scientific and Technical Information of China (English)

    Shiming HUANG; Wei XIE; Chengyou KAN; Yajie LI; Deshan LIU

    2005-01-01

    @@ 1Introduction Soap-free emulsion copolymerization of styrene (St) and sodium sulfonate styrene (NaSS) could yield homodisperse sulfonate-containing particles with clean surface. But the incorporation of NaSS could never be increased beyond 2.6 % by weight in the conventional batch and seeded emulsion copolymerization in the absence of emulsifier because large amounts of soluble polyelectrolyte would unstablize the reaction system if excessive amount of NaSS was used[1]. In our work, semi-continuous copolymerizations were carried out in the presence of mixed emulsifiers, and a new method to purify the latex polymer was developed. The influences of the NaSS mole ratio in the total monomers and the monomer addition time on the S content in the purified copolymer were investigated by elemental analysis.

  4. Proton Conduction in Sulfonated Organic-Inorganic Hybrid Monoliths with Hierarchical Pore Structure.

    Science.gov (United States)

    von der Lehr, Martin; Seidler, Christopher F; Taffa, Dereje H; Wark, Michael; Smarsly, Bernd M; Marschall, Roland

    2016-09-28

    Porous organic-inorganic hybrid monoliths with hierarchical porosity exhibiting macro- and mesopores are prepared via sol-gel process under variation of the mesopore size. Organic moieties in the pore walls are incorporated by substituting up to 10% of the silicon precursor tetramethylorthosilicate with bisilylated benzene molecules. After functionalization with sulfonic acid groups, the resulting sulfonated hybrid monoliths featuring a bimodal pore structure are investigated regarding proton conduction depending on temperature and relative humidity. The hierarchical pore system and controlled mesopore design turn out to be crucial for sulfonation and proton conduction. These sulfonated hybrid hierarchical monoliths containing only 10% organic precursor exhibit higher proton conduction at different relative humidities than sulfonated periodic mesoporous organosilica made of 100% bisilylated precursors exhibiting solely mesopores, even with a lower concentration of sulfonic acid groups.

  5. Sulfonation and characterization of styrene-indene copolymers for the development of proton conducting polymer membranes

    Directory of Open Access Journals (Sweden)

    Cristiane M. Becker

    2012-01-01

    Full Text Available The aim of this work is to obtain polymer precursors based on styrene copolymers with distinct degrees of sulfonation, as an alternative material for fuel cell membranes. Acetyl sulfate was used to carry out the sulfonation and the performance of the polyelectrolyte was evaluated based on the content of acid polar groups incorporated into the macromolecular chain. Polymeric films were produced by blending the sulfonated styrene-indene copolymer with poly(vinylidene fluoride. The degree of sulfonation of the polymer was strongly affected by the sulfonation reaction parameters, with a direct impact on the ionic exchange capacity and the ionic conductivity of the sulfonated polymers and the membranes obtained from them. The films produced with the blends showed more suitable mechanical properties, although the conductivity of the membranes was still lower than that of commercially available membranes used in fuel cells.

  6. Study on the generation of perfluorooctane sulfonate from the aqueous film-forming foam.

    Science.gov (United States)

    Kishi, Takahiro; Arai, Mitsuru

    2008-11-15

    Perfluorooctane sulfonate (C(8)HF(17)SO(3)) and perfluorooctane acid (C(8)HF(15)O(2)) are artificial chemicals and have been used all over the world, mainly as water repellent agents, fluorochemical surfactants, coating agents, etc. However, perfluorooctane sulfonate and perfluorooctane acid are environmental contaminants because of their stability, bio-accumulativeness, and long-term persistence in the ecological environment. At the present day, they are diffused all over the world. Lately, this diffusion is viewed with suspicion and there is a movement towards their restriction, even if the environmental fate of them is still under investigation. Fluorochemical surfactants are key compounds in the aqueous film-forming foam (AFFF) formulations. AFFFs are used for massive conflagration such as industrial fire and petroleum fire because of their efficient fire control. On the other hand, a lot of AFFFs are used in case of massive conflagration and most of them enter ocean and groundwater. Actually, perfluorooctane sulfonate and perfluorooctane sulfonate related substances were detected from the fire-fighting facility of US forces. Therefore, there is the possibility of generating perfluorooctane sulfonate and perfluorooctane sulfonate related substances from fluorochemical surfactants in the AFFFs. In this study, activated sludge added AFFF were analyzed for perfluorooctane sulfonate and perfluorooctane acid with time. And the perfluorooctane sulfonate was directly detected after 2 days using LC-MS. This shows that AFFF can be decomposed perfluorooctane sulfonate by microorganisms easily. However, perfluorooctane sulfonate would not decompose at all. Additionally, activated sludge added N-polyoxyethylene-N-propyl perfluorooctane sulfonamide which is one of the fluorochemical surfactants used in the AFFF was analyzed for perfluorooctane sulfonate and perfluorooctane acid with time and the perfluorooctane sulfonate was detected too.

  7. A STUDY OF THE HEAT OF HYDRATION OF SULFONIC ACID RESINS

    Institute of Scientific and Technical Information of China (English)

    XURongnan; JIJunyan; 等

    1992-01-01

    The heat of hydration of dry sulfonic acid resin in different comcentrations of sulfuric acid has been determined. The heat of hydration of the resin in H2O is 143.4J/g(resin). The greater the concentration of sulfuric acid,the less the heat will be released.The hydrate formed from three sulfonic acid groups and one water molecule is the most stable one of all the hydrates of sulfonic acid resin and water.

  8. Las incumbencias

    Directory of Open Access Journals (Sweden)

    Emilio Fermín Mignone

    2013-05-01

    Full Text Available Desde mediados de la década de 1970 se desarrolló en la Argentina un sistema dirigido a establecer las denominadas incumbencias de las profesiones universitarias, que ha alcanzado notable dimensión. Sin embargo, no conozco hasta el presente un análisis pormenorizado de su evolución ni de sus fundamentos legales; ni una reflexión acerca de sus propósitos, ventajas e inconvenientes. El propósito de este trabajo es iniciar dicho examen para contribuir con una propuesta racional al desenvolvimiento de una política universitaria orientada hacia el acrecentamiento de la autonomía de los establecimientos, la distinción entre el título académico y la habilitación profesional, la desregulación, en la medida de lo razonable, del ejercicio de las profesiones y la evaluación periódica de la calidad de la educación superior, a fin de procurar su excelencia, pertinencia, eficiencia y equidad

  9. Chemical and microbial community analysis during aerobic biostimulation assays of non-sulfonated alkyl-benzene-contaminated groundwater.

    Science.gov (United States)

    Martínez-Pascual, Eulàlia; Jiménez, Nuria; Vidal-Gavilan, Georgina; Viñas, Marc; Solanas, A M

    2010-10-01

    A chemical and microbial characterization of lab-scale biostimulation assays with groundwater samples taken from an industrial site in which the aquifer had been contaminated by linear non-sulfonate alkyl benzenes (LABs) was carried out for further field-scale bioremediation purposes. Two lab-scale biodegradability assays were performed, one with a previously obtained gas-oil-degrading consortium and another with the native groundwater flora. Results for the characterization of the groundwater microbial population of the site revealed the presence of an important LAB-degrading microbial population with a strong degrading capacity. Among the microorganisms identified at the site, the detection of Parvibaculum lavamentivorans, which have been described in other studies as alkyl benzene sulfonates degraders, is worth mentioning. Incubation of P. lavamentivorans DSMZ13023 with LABs as reported in this study shows for the first time the metabolic capacity of this strain to degrade such compounds. Results from the biodegradation assays in this study showed that the indigenous microbial population had a higher degrading capacity than the gas-oil-degrading consortium, indicating the strong ability of the native community to adapt to the presence of LABs. The addition of inorganic nutrients significantly improved the aerobic biodegradation rate, achieving levels of biodegradation close to 90%. The results of this study show the potential effectiveness of oxygen and nutrients as in situ biostimulation agents as well as the existence of a complex microbial community that encompasses well-known hydrocarbon- and LAS-degrading microbial populations in the aquifer studied.

  10. Sulfonated phenolic material and its use in post primary oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Pardue, J. E.; Stapp, P. R.

    1984-09-04

    Sulfonated phenolic compounds as well as sulfomethylated phenolic compounds, surfactant systems containing such compound and the use of such surfactant systems in post primary oil recovery are disclosed.

  11. Quinone-mediated decolorization of sulfonated azo dyes by cells and cell extracts from Sphingomonas xenophaga

    Institute of Scientific and Technical Information of China (English)

    JIAO Ling; LU Hong; ZHOU Jiti; WANG Jing

    2009-01-01

    The effects of various quinone compounds on the decolorization rates of sulfonated azo dyes by Sphingomonas xenophaga QYY were investigated. The results showed that anthraquinone-2-sulfonate (AQS) was the most effective redox mediator and AQS reduction was the rate-limited step of AQS-mediated decolorization of sulfonated azo dyes. Based on AQS biological toxicity tests, it was assumed that AQS might enter the cells to kill them. In the cytoplasmic extracts from strain QYY, AQS effectively increased decolorization rates of sulfonated azo dyes than other quinone compounds. In addition, we found a NADH/FMN-dependent AQS reductase using nondenaturing polyacrylamide gel electrophoresis (Native-PAGE).

  12. Las Farmacodependencias

    Directory of Open Access Journals (Sweden)

    José Francisco Socarrás

    1994-09-01

    Full Text Available

    Ahora, cuando la Corte Constitucional ha despenalizado al farmacodependiente por el consumo de drogas, conviene informar sobre las consecuencias perjudiciales de estas. A quienes deseen un conocimiento detallado al respecto, les recomiendo documentarse en “Enciclopedia de Psiquiatría”, publicada por “El Ateneo” en Buenos Aires.

    El Capítulo respectivo es del doctor Daniel L. Murguia. El denominador corriente de su abuso es sencillamente la dependencia, nombre propuesto por la Organización Mundial de la Salud, definido como el “estado psíquico y a veces físico causado por la interacción entre un organismo vivo y un fármaco”. Su carácter esencial es el impulso psicofísico a consumir el producto en forma continua o periódica, con el fin de experimentar los efectos que acarrea y evitar los malestares de su privación. Todas las drogas del respectivo género, consumidas a dosis altas, tienen efectos psicotóxicos que alteran la conducta y en algunos casos conducen a la muerte.

    Los expertos de la Organización Mundial califican las mencionadas sustancias en seis grupos, a saber:

    1. Morfina y opiáceas, los cuales crean dependencia física y psicológica, con tolerancia precoz, necesidad de aumentar las dosis y síndrome de abstinencia bastante peligroso. Entre los derivados se cuentan los siguientes: Hidromorfina (Dilaudid; oximorfina (Nurmophan; heroína,
    éter diacético de la morfina (Diacetilmorfina; codeína (Metilmorfina; hidrocodeína (Hicadan’ oxicodeína (Perdocan. Los efectos de los opiáceo~ son los siguientes: analgesia, depresión respiratoria y espasmo gastrointestinal. Las dosis tóxicas pueden provocar convulsiones.

    2. Barbitúricos, alcohol y sedantes como el fenobarbital, que provocan así mismo dependencia física.

    3. Anfetaminas, en particular la Bencedrina inhalante, que acarrea dependencia psicológica.

    4. Cocaína, cuya dependencia psíquica es tal que muchos

  13. Properties of sulfonated cation-exchangers made from petroleum asphaltites

    Energy Technology Data Exchange (ETDEWEB)

    Pokonova, Yu.V.; Pol' kin, G.B.; Proskuryakov, V.A.

    1982-01-10

    The use of ion-exchangers in radiochemical technology is accompanied by changes of their properties under the influence of ionizing radiation. The rate of development of these processes depends on the nature and structure of the matrix and on the nature and amount of ionic groups. We have proposed a method of synthesis of ion-exchangers resistant to ..gamma.. radiation from petroleum asphaltites. Continuing these investigations, we prepared cation-exchangers by sulfonation of a mixture of petroleum asphaltites and acid asphalt. An investigation of their radiation resistance is described in this paper.

  14. Colonic necrosis due to calcium polystyrene sulfonate (Kalimate) not suspended in sorbitol.

    Science.gov (United States)

    Castillo-Cejas, María Dolores; de-Torres-Ramírez, Inés; Alonso-Cotoner, Carmen

    2013-04-01

    Cation-exchange resins are used in the management of hyperkalemia, particularly in patients with end-stage renal disease. These resins were associated with gastrointestinal tract lesions, especially sodium polystyrene sulfonate (Kayexalate) mixed with sorbitol. We present a case of colonic necrosis after the administration of calcium polystyrene sulfonate (Kalimate) not suspended in sorbitol.

  15. Colonic necrosis due to calcium polystyrene sulfonate (Kalimate) not suspended in sorbitol

    OpenAIRE

    María Dolores Castillo-Cejas; Inés de Torres-Ramírez; Carmen Alonso-Cotoner

    2013-01-01

    Cation-exchange resins are used in the management of hyperkalemia, particularly in patients with end-stage renal disease. These resins were associated with gastrointestinal tract lesions, especially sodium polystyrene sulfonate (Kayexalate) mixed with sorbitol. We present a case of colonic necrosis after the administration of calcium polystyrene sulfonate (Kalimate) not suspended in sorbitol.

  16. 78 FR 62443 - Perfluoroalkyl Sulfonates and Long-Chain Perfluoroalkyl Carboxylate Chemical Substances; Final...

    Science.gov (United States)

    2013-10-22

    ... AGENCY 40 CFR Parts 9 and 721 RIN 2070-AJ95 Perfluoroalkyl Sulfonates and Long-Chain Perfluoroalkyl... new use rule (SNUR) for perfluoroalkyl sulfonate (PFAS) chemical substances to add PFAS chemical.... EPA is also finalizing a SNUR for long-chain perfluoroalkyl carboxylate (LCPFAC) chemical...

  17. Colonic necrosis due to calcium polystyrene sulfonate (Kalimate not suspended in sorbitol

    Directory of Open Access Journals (Sweden)

    María Dolores Castillo-Cejas

    2013-04-01

    Full Text Available Cation-exchange resins are used in the management of hyperkalemia, particularly in patients with end-stage renal disease. These resins were associated with gastrointestinal tract lesions, especially sodium polystyrene sulfonate (Kayexalate mixed with sorbitol. We present a case of colonic necrosis after the administration of calcium polystyrene sulfonate (Kalimate not suspended in sorbitol.

  18. Cationic and radical intermediates in the acid photorelease from aryl sulfonates and phosphates.

    Science.gov (United States)

    Terpolilli, Marco; Merli, Daniele; Protti, Stefano; Dichiarante, Valentina; Fagnoni, Maurizio; Albini, Angelo

    2011-01-01

    The irradiation of a series of phenyl sulfonates and phosphates leads to the quantitative release of acidity with a reasonable quantum yield (≈0.2). Products characterization, ion chromatography analysis and potentiometric titration are consistent with the intervening of two different paths in this reaction, viz. cationic with phosphates and (mainly) radical with sulfonates.

  19. 40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

    Science.gov (United States)

    2010-07-01

    ... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737)...

  20. Coating of Sulfonic Silica onto Magnetite from Marina Beach Iron sand, Semarang, Indonesia

    Science.gov (United States)

    Azmiyawati, C.; Suyati, L.; Taslimah; Anggraeni, R. D.

    2017-02-01

    The mineral iron oxide is the main component of sand iron that are abundant in nature. Mineral iron oxide not yet widely applied into more useful products. The main component of iron ore is magnetite. Magnetite can be used as a basic ingredient in the manufacture of magnetite-modified silica adsorbent sulfonate. In this research, the adsorbent made from sulfonic functionalized silica-coated magnetic particle has been successfully produced, with the magnetite was obtained from iron sand at Marina Beach, Semarang Indonesia. This adsorbent was then used as a metal ion preconcentration media. From the research that it was found that the sulfonic has been bound to the silica marked by the emergence of element S on EDX. Whilst, the evidence that silica has coated on the magnetite could be seen from the SEM images which showed the morphology of sulfonic functionalized silica-coated magnetic particles were larger than the sulfonic functionalized silica without magnetite. From the DSC results showed that the addition of magnetite on sulfonic functionalized silica did not change the heat resistance of the sulfonic functionalized silica. Based on the XRD patterns show that magnetite sulfonate silica was formed.

  1. Sulfonated polyetherketone (SPEK-C) films investigated by positron annihilation lifetime spectroscopy and atomic force microscopy

    Institute of Scientific and Technical Information of China (English)

    Htwe Htwe Yin; YIN Ze-Jie; TANG Shi-Biao; HUANG Huan; ZHU Da-Ming

    2005-01-01

    The characterization of sulfonated polyetherketone (SPEK-C) films was investigated by using positron annihilation lifetime spectroscopy (PALS) and atomic force microscopy (AFM). It was found that free volume radius and intensity depend on the variation of sulfonation degree and solvent evaporation time of the films. Pore size and distribution determined from PALS and AFM measurements showed reasonable agreement.

  2. APPLICATION OF THE SULFONATE ESTER GROUP AS A LINKER FOR SOLID PHASE ORGANIC SYNTHESIS

    Institute of Scientific and Technical Information of China (English)

    SUN Weimin; LUO Juntao; HUANG Wenqiang; ZHU Xiaoxia

    2001-01-01

    A use of Sulfonate ester as a linker in synthesis of ω-aminoalkanols was reported. Diols were tethered onto polystyryl sulfonyl chloride resin, yielding sulfonate resins (2). After cleaved by diethyl amine, diisopropylamine and propylamine respectively, three ω-aminoalkanols were obtained.

  3. Ionomeric membranes based on partially sulfonated poly(styrene) : synthesis, proton conduction and methanol permeation

    NARCIS (Netherlands)

    Picchioni, F.; Tricoli, V.; Carretta, N.

    2000-01-01

    Homogeneuosly sulfonated poly(styrene) (SPS) was prepared with various concentration of sulfonic acid groups in the base polymer. Membranes cast from these materials were investigated in relation to proton conductivity and methanol permeability in the temperature range from 20°C to 60°C. It was foun

  4. APPLICATION OF THE SULFONATE ESTER GROUP AS A LINKER FOR SOLID PHASE ORGANIC SYNTHESIS

    Institute of Scientific and Technical Information of China (English)

    SUNWeimin; ZHUXiaoxia; 等

    2001-01-01

    A use of sulfonate ester as a linker in synthesis of w-aminoalkanols was reporte.Diols were tethered onto polystyryl sulfonyl chloride resin,yielding sulfonate resins(2).After cleaved by diethyl amine,diisopropylamine and propylamine respectively,three w-aminoalkanlos were obtained.

  5. Julia Olefination as a General Route to Phenyl (α-Fluoro)vinyl Sulfones

    Science.gov (United States)

    He, Maggie; Ghosh, Arun K.; Zajc, Barbara

    2009-01-01

    Mild and efficient synthesis of phenyl (α-fluoro)vinyl sulfones via condensation of aldehydes and a ketone with a novel benzothiazolyl based bis-sulfone reagent is reported and this proceeds with moderate to good Z-stereoselectivity. PMID:19888442

  6. Mass spectrometric composition and structural studies of petroleum sulfonates and petroleum sulfonate components for utilization in tertiary petroleum production

    Energy Technology Data Exchange (ETDEWEB)

    Belafi, L.; Decsy, Z.; Kerenyi, E.; Lukacs, J.

    1984-01-01

    A separation and mass spectrometric analytical method was developed for the separation and characterization of the monosulfonate fractions of petroleum sulfonate products. The technique is based on distillation and preparative column and thin-layer chromatography. The structure and carbon number distributions of monosulfonate fractions transformed to metilesters were measured based on their low resolution molecular mass spectra. The conditions of an actual petroleum container were simulated and the measurement of the effluent composition during its discharge revealed no change in the composition of monosulfonates.

  7. Radiation-chemical synthesis of polypropylene fabrics with sulfonic acid functional groups

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Hyun Kug; Park, Jung Soo; Han, Do Hung, E-mail: dhhan@yumail.ac.kr; Bondar, Iuliia, E-mail: juliavad@yahoo.co

    2011-04-01

    A sorption-active material carrying sulfonic acid groups was synthesized by the radiation-induced graft polymerization of styrene monomer onto the surface of non-woven polypropylene fabric, followed by sulfonation of the grafted polystyrene chains. The effect of the main experimental parameters (absorbed dose, monomer concentration, reaction time) on the styrene degree of grafting was investigated. The sulfonation process with 5% chlorosulfonic acid at room temperature was investigated in detail and the optimal sulfonation conditions for the samples with a medium degree of grafting (70-140%) were determined. Densities of 3.5-5 meq/g were obtained by applying those sorption-active PP fabrics with a sulfonic acid group.

  8. Nanostructured membranes and electrodes with sulfonic acid functionalized carbon nanotubes

    KAUST Repository

    Tripathi, Bijay Prakash

    2011-02-01

    Herein we report the covalent functionalization of multiwall carbon nanotubes by grafting sulfanilic acid and their dispersion into sulfonated poly(ether ether ketone). The nanocomposites were explored as an option for tuning the proton and electron conductivity, swelling, water and alcohol permeability aiming at nanostructured membranes and electrodes for application in alcohol or hydrogen fuel cells and other electrochemical devices. The nanocomposites were extensively characterized, by studying their physicochemical and electrochemical properties. They were processed as self-supporting films with high mechanical stability, proton conductivity of 4.47 × 10 -2 S cm-1 at 30 °C and 16.8 × 10-2 S cm-1 at 80 °C and 100% humidity level, electron conductivity much higher than for the plain polymer. The methanol permeability could be reduced to 1/20, keeping water permeability at reasonable values. The ratio of bound water also increases with increasing content of sulfonated filler, helping in keeping water in the polymer in conditions of low external humidity level. © 2010 Elsevier B.V.

  9. Nanostructured membranes and electrodes with sulfonic acid functionalized carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Tripathi, Bijay P. [Electro-Membrane Processes Division, Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial Research (CSIR), G.B. Marg, Bhavnagar 364002, Gujarat (India); Department of Membranes for Sustainable Energy, GKSS Research Centre Geesthacht GmbH, Max Planck Str. 1, D-21502 Geesthacht (Germany); Schieda, M. [Department of Membranes for Sustainable Energy, GKSS Research Centre Geesthacht GmbH, Max Planck Str. 1, D-21502 Geesthacht (Germany); Shahi, Vinod K. [Electro-Membrane Processes Division, Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial Research (CSIR), G.B. Marg, Bhavnagar 364002, Gujarat (India); Nunes, Suzana P. [King Abdullah University of Science and Technology, Thuwal 23955-6900 (Saudi Arabia)

    2011-02-01

    Herein we report the covalent functionalization of multiwall carbon nanotubes by grafting sulfanilic acid and their dispersion into sulfonated poly(ether ether ketone). The nanocomposites were explored as an option for tuning the proton and electron conductivity, swelling, water and alcohol permeability aiming at nanostructured membranes and electrodes for application in alcohol or hydrogen fuel cells and other electrochemical devices. The nanocomposites were extensively characterized, by studying their physicochemical and electrochemical properties. They were processed as self-supporting films with high mechanical stability, proton conductivity of 4.47 x 10{sup -2} S cm{sup -1} at 30 C and 16.8 x 10{sup -2} S cm{sup -1} at 80 C and 100% humidity level, electron conductivity much higher than for the plain polymer. The methanol permeability could be reduced to 1/20, keeping water permeability at reasonable values. The ratio of bound water also increases with increasing content of sulfonated filler, helping in keeping water in the polymer in conditions of low external humidity level. (author)

  10. Nanostructured membranes and electrodes with sulfonic acid functionalized carbon nanotubes

    Science.gov (United States)

    Tripathi, Bijay P.; Schieda, M.; Shahi, Vinod K.; Nunes, Suzana P.

    Herein we report the covalent functionalization of multiwall carbon nanotubes by grafting sulfanilic acid and their dispersion into sulfonated poly(ether ether ketone). The nanocomposites were explored as an option for tuning the proton and electron conductivity, swelling, water and alcohol permeability aiming at nanostructured membranes and electrodes for application in alcohol or hydrogen fuel cells and other electrochemical devices. The nanocomposites were extensively characterized, by studying their physicochemical and electrochemical properties. They were processed as self-supporting films with high mechanical stability, proton conductivity of 4.47 × 10 -2 S cm -1 at 30 °C and 16.8 × 10 -2 S cm -1 at 80 °C and 100% humidity level, electron conductivity much higher than for the plain polymer. The methanol permeability could be reduced to 1/20, keeping water permeability at reasonable values. The ratio of bound water also increases with increasing content of sulfonated filler, helping in keeping water in the polymer in conditions of low external humidity level.

  11. Polyaniline synthesized with functionalized sulfonic acids for blends manufacture

    Directory of Open Access Journals (Sweden)

    Mara Joelma Raupp Cardoso

    2007-12-01

    Full Text Available Polyaniline (PAni, an electronic conductive polymer, has poor mechanical properties, such as low tensile, compressive and flexural strength that render PAni a non-ideal material to be processed for practical applications. Desired properties of polyaniline can be enhanced by mixing it with a polymer that has good mechanical properties. In this work, PAni was synthesised using functionalized sulfonic acids like camphorsulfonic acid (CSA and dodecilbenzene sulfonic acid (DBSA in order to promote PAni doping and improve its solubility, making possible conductive blends manufacture. The different forms of PAni were characterized by infra-red spectroscopy, thermal analysis, scanning electron microscopy and conductivity measurements. A conductive blend composed of PAni/DBSA and lower density polyethylene (LDPE was obtained via solubilization method and its thermal, morphological and electrical properties were investigated. Concentrations as low as 5 wt. (% of PAni was able to lead to electrical conductivities of PAni/LDPE blends in the range of 10-3 S.cm-1, showing great potential to be used in antistatic packing, electromagnetic shielding, anti-corrosion shielding or as a semiconductor.

  12. Selective sorption of perfluorooctane sulfonate on molecularly imprinted polymer adsorbents

    Institute of Scientific and Technical Information of China (English)

    Shubo DENG; Danmeng SHUAI; Qiang YU; Jun HUANG; Gang YU

    2009-01-01

    Perfluorooctane sulfonate (PFOS), as a potential persistent organic pollutant, has been widely detected in water environments, and has become a great concern in recent years. PFOS is very stable and difficult to decompose using conventional techniques. Sorption may be an attractive method to remove it from water. In this study, the molecularly imprinted polymer (MIP) adsorbents were prepared through the polymerization of 4-vinylpyridine under different preparation conditions in order to remove perfluorooctane sulfonate (PFOS) from water. The MIP adsorbents using perfluorooctanoic acid (PFOA) as the template had good imprinting effects and could selectively remove PFOS from aqueous solution. The sorption behaviors including sorption kinetics,isotherms, and effect of pH, salt, and competitive anions were investigated. Experimental results showed that the sorption of PFOS On the MIP adsorbents was very fast, pH-dependent, and highly selective. The achieved fast sorption equilibrium within 1 h was attributed to the surface sorption on the fine adsorbents. The sorption isotherms showed that the sorption selectivity of PFOS on the MIP adsorbents decreased at high PFOS concentrations, which may be due to the double-layer sorption and the formation of PFOS micelles on the sorbent surface. The sorption of PFOS on the MIP adsorbents was mainly dominated by the electrostatic interaction between the protonated vinylpyridine on the adsorbent surface and the anionic PFOS. The prepared MIP adsorbents can potentially be applied in water and wastewater treatment for selective removal of PFOS.

  13. 40 CFR 417.140 - Applicability; description of the neutralization of sulfuric acid esters and sulfonic acids...

    Science.gov (United States)

    2010-07-01

    ... neutralization of sulfuric acid esters and sulfonic acids subcategory. 417.140 Section 417.140 Protection of... MANUFACTURING POINT SOURCE CATEGORY Neutralization of Sulfuric Acid Esters and Sulfonic Acids Subcategory § 417.140 Applicability; description of the neutralization of sulfuric acid esters and sulfonic...

  14. Highly charged proton-exchange membrane. Sulfonated poly(ether sulfone)-silica polyelectrolyte composite membranes for fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Shahi, Vinod K. [Electro-Membrane Processes Division, Central Salt and Marine Chemicals Research Institute, Bhavnagar-364002, Gujarat (India)

    2007-01-15

    Sulfonation of poly(ether sulfone) was carried out with chlorosulphonic acid in chloroform and its composite proton-exchange membrane was prepared using aminopropyltriethoxysilane as inorganic precursor by sol-gel in acidic medium. These membranes were further subjected to phosphorylation with phosphorous acid for introducing phosphonic acid functionality at inorganic segment. Extent of sulphonation was estimated by {sup 1}H-NMR spectroscopy while introduction of phosphonic acid groups was confirmed by FTIR spectroscopy and ion-exchange capacity studies. Different membranes, with varied silica content without and with phosphorylation, were characterized for their thermal and mechanical stabilities, physicochemical and electrochemical properties using thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), scanning electron microscopy (SEM), aq. methanol uptake studies, proton conductivity and methanol permeability measurements. The silica content in the membrane matrix and effect of phosphorylation was optimized as a function of membrane properties. Activation energy required for the proton transport across the membrane was also estimated and found to be comparable with Nafion 117 membrane. From the frictional interpretation and estimation of selectivity parameter it was observed that SPS-Si composite phosphorylated membrane with 20% silica content (SPS-Si(P)/20) resulted in the best proton-exchange membrane, which exhibited quite higher selectivity parameter in comparison to Nafion 117 for direct methanol fuel cell applications. Also, current-voltage polarization characteristics of SPS-Si(P)/20 membrane measured in direct methanol fuel cell, were found to be comparable to the Nafion 117 membrane. (author)

  15. Coupling hydrogen separation with butanone hydrogenation in an electrochemical hydrogen pump with sulfonated poly (phthalazinone ether sulfone ketone) membrane

    Science.gov (United States)

    Huang, Shiqi; Wang, Tao; Wu, Xuemei; Xiao, Wu; Yu, Miao; Chen, Wei; Zhang, Fengxiang; He, Gaohong

    2016-09-01

    This work reports the novel work of coupling H2/CO2 separation with biomass-derived butanone hydrogenation in non-fluorinated sulfonated poly (phthalazinone ether sulfone ketone) (SPPESK) electrochemical hydrogen pump (EHP) reactor. Due to higher resistance to swelling, SPPESK-based EHP reactor exhibits more excellent reaction rate in elevated temperature (60 °C) and higher butanone concentration (2 M) as 270, 260 nmol cm-2 s-1, respectively, higher than 240, 200 nmol cm-2 s-1of Nafion-based EHP reactors. Also, the SPPESK-based EHP reactor remains 90% of initial hydrogenation rate after 4 batches, better than that of Nafion-based EHP reactors, which is only 62%. The energy efficiency of EHP separator reaches 40% under H2/CO2 mixture feed mode, and electricity of about 0.3 kWh is consumed per Nm3 H2 product, being superior to energy consumption compared with alternative processes like PSA and electrolysis of water. In addition, SPPESK-based EHP exhibits better hydrogenation stability due to lower CO2 permeation than Nafion. With increasing CO2 content in H2 feed, hydrogenation rate almost keeps constant at around 210 nmol cm-2 s-1 in SPPESK-based EHP reactor while decreases fast to 50 nmol cm-2 s-1 in Nafion/PTFE-based EHP reactor. These results show integration of gas separation with hydrogenation reactor is feasible in SPPESK-based EHP reactor.

  16. Red electroluminescence of ruthenium sensitizer functionalized by sulfonate anchoring groups.

    Science.gov (United States)

    Shahroosvand, Hashem; Abbasi, Parisa; Mohajerani, Ezeddin; Janghouri, Mohammad

    2014-06-28

    We have synthesized five novel Ru(ii) phenanthroline complexes with an additional aryl sulfonate ligating substituent at the 5-position [Ru(L)(bpy)2](BF4)2 (1), [Ru(L)(bpy)(SCN)2] (2), [Ru(L)3](BF4)2 (3), [Ru(L)2(bpy)](BF4)2 (4) and [Ru(L)(BPhen)(SCN)2] (5) (where L = 6-one-[1,10]phenanthroline-5-ylamino)-3-hydroxynaphthalene 1-sulfonic, bpy = 2,2'-bipyridine, BPhen = 4,7-diphenyl-1,10-phenanthroline), as both photosensitizers for oxide semiconductor solar cells (DSSCs) and light emitting diodes (LEDs). The absorption and emission maxima of these complexes red shifted upon extending the conjugation of the phenanthroline ligand. Ru phenanthroline complexes exhibit broad metal to ligand charge transfer-centered electroluminescence (EL) with a maximum near 580 nm. Our results indicated that a particular structure (2) can be considered as both DSSC and OLED devices. The efficiency of the LED performance can be tuned by using a range of ligands. Device (2) has a luminance of 550 cd m(-2) and maximum efficiency of 0.9 cd A(-1) at 18 V, which are the highest values among the five devices. The turn-on voltage of this device is approximately 5 V. The role of auxiliary ligands in the photophysical properties of Ru complexes was investigated by DFT calculation. We have also studied photovoltaic properties of dye-sensitized nanocrystalline semiconductor solar cells based on Ru phenanthroline complexes and an iodine redox electrolyte. A solar energy to electricity conversion efficiency (η) of 0.67% was obtained for Ru complex (2) under standard AM 1.5 irradiation with a short-circuit photocurrent density (Jsc) of 2.46 mA cm(-2), an open-circuit photovoltage (Voc) of 0.6 V, and a fill factor (ff) of 40%, which are all among the highest values for ruthenium sulfonated anchoring groups reported so far. Monochromatic incident photon to current conversion efficiency was 23% at 475 nm. Photovoltaic studies clearly indicated dyes with two SCN substituents yielded a higher Jsc for the

  17. Celecoxib influences steroid sulfonation catalyzed by human recombinant sulfotransferase 2A1.

    Science.gov (United States)

    Ambadapadi, Sriram; Wang, Peter L; Palii, Sergiu P; James, Margaret O

    2015-08-01

    Celecoxib has been reported to switch the human SULT2A1-catalyzed sulfonation of 17β-estradiol (17β-E2) from the 3- to the 17-position. The effects of celecoxib on the sulfonation of selected steroids catalyzed by human SULT2A1 were assessed through in vitro and in silico studies. Celecoxib inhibited SULT2A1-catalyzed sulfonation of dehydroepiandrosterone (DHEA), androst-5-ene-3β, 17β-diol (AD), testosterone (T) and epitestosterone (Epi-T) in a concentration-dependent manner. Low μM concentrations of celecoxib strikingly enhanced the formation of the 17-sulfates of 6-dehydroestradiol (6D-E2), 17β-dihydroequilenin (17β-Eqn), 17β-dihydroequilin (17β-Eq), and 9-dehydroestradiol (9D-E2) as well as the overall rate of sulfonation. For 6D-E2, 9D-E2 and 17β-Eqn, celecoxib inhibited 3-sulfonation, however 3-sulfonation of 17β-Eq was stimulated at celecoxib concentrations below 40 μM. Ligand docking studies in silico suggest that celecoxib binds in the substrate-binding site of SULT2A1 in a manner that prohibits the usual binding of substrates but facilitates, for appropriately shaped substrates, a binding mode that favors 17-sulfonation.

  18. EFFECTIVENESS OF WASTE STABILIZATION PONDS IN REMOVAL OF LINEAR ALKYL BENZENE SALFONATE (LAS)

    OpenAIRE

    2013-01-01

    Detergents contain synthetic or organic surface active agents called surfactants, which are derived from petroleum product precursors. They have the common property of lowering the surface tensions of water thus allowing dirt or grease adhered to various articles to be washed off. Linear alkyl benzene sulfonate (LAS) is a most commonly used anionic surfactant. Discharge of raw or treated wastewater containing this chemical substance into the environment causes major public health and envirome...

  19. Radiation-induced crosslinking of poly(styrene–butadiene–styrene) block copolymers and their sulfonation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sun-Young [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 29 Geumgu-gil, Jeongeup-si, Jeollabuk-do 580-185 (Korea, Republic of); Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Song, Ju-Myung; Sohn, Joon-Yong [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 29 Geumgu-gil, Jeongeup-si, Jeollabuk-do 580-185 (Korea, Republic of); Shul, Yong-Gun [Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Shin, Junhwa, E-mail: shinj@kaeri.re.kr [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 29 Geumgu-gil, Jeongeup-si, Jeollabuk-do 580-185 (Korea, Republic of)

    2013-12-01

    Highlights: • The c-SBS films were prepared using a gamma ray or electron beam. • The crosslinking degree of the c-SBS films were increased with the irradiation dose. • The prepared c-SBS films were sulfonated with various concentration of CSA. • The sulfonation of the c-SBS film is largely dependent on the concentration of CSA. • The sulfonation process is progressed from the surface to the inner part of c-SBS film. -- Abstract: Several crosslinked poly(styrene–butadiene–styrene) (c-SBS) block copolymer films were prepared using a gamma ray or electron beam with various irradiation doses and the prepared c-SBS film was then subjected to sulfonation using a chlorosulfonic acid (CSA) solution to introduce a sulfonic acid group. To estimate the degree of crosslinking, the gel fractions and FT-IR spectra of the c-SBS films were used and the results indicate that the degree of crosslinking is increased with an increase in the radiation dose. The surface morphology and mechanical property of the c-SBS films were observed using SEM and UTM instruments, respectively. The sulfonated c-SBS films were investigated by measuring the ion exchange capacity (IEC) and by observing the cross-sectional distribution patterns of sulfonic acid group using an SEM-EDX instrument. The IEC and SEM-EDX studies indicate that the sulfonated c-SBS membranes can be successfully prepared through the radiation crosslinking of the SBS film and the subsequent sulfonation with a diluted CSA solution.

  20. Characteristics of polyaniline electropolymerized in camphor sulfonic acid

    Energy Technology Data Exchange (ETDEWEB)

    Santos, J.R. Jr. [Instituto de Quimica de Sao Carlos/DFQ/USP, C.P. 369, 13560-970, Sao Carlos, SP (Brazil); Malmonge, J.A. [Instituto de Fisica de Sao Carlos/DFCM/USP, C.P. 369, 13560-970, Sao Carlos, SP (Brazil); Conceicao Silva, A.J.G. [Instituto de Fisica de Sao Carlos/DFCM/USP, C.P. 369, 13560-970, Sao Carlos, SP (Brazil); Motheo, A.J. [Instituto de Quimica de Sao Carlos/DFQ/USP, C.P. 369, 13560-970, Sao Carlos, SP (Brazil); Mascarenhas, Y.P. [Instituto de Fisica de Sao Carlos/DFCM/USP, C.P. 369, 13560-970, Sao Carlos, SP (Brazil); Mattoso, L.H.C. [Instituto de Fisica de Sao Carlos/DFCM/USP, C.P. 369, 13560-970, Sao Carlos, SP (Brazil)

    1995-03-01

    Polyaniline was electropolymerized by cyclic voltammetry in the presence of camphor sulfonic acid (CSA), and the resulting film was characterized by solubility tests, UV-Vis absorption, electron microscopy, X-ray diffraction and conductivity measurements. The use of the functionalized acid - CSA - made it possible to obtain the as-electropolymerized polymer (in the doped state) soluble in organic solvents such as m-cresol and chloroform. The UV-Vis spectra of PAni-CSA in m-cresol presented a free-carrier tail commencing at 1000nm which may be attributed to secondary doping due to conformational changes of the polymer chains. After treatment with m-cresol the film exhibited an increase of conductivity reaching ca. 100S/cm. (orig.)

  1. Chemoselective allylation of ketones in ionic liquids containing sulfonate anions.

    Science.gov (United States)

    Galletti, Paola; Moretti, Fabio; Samorì, Chiara; Tagliavini, Emilio

    2009-01-01

    The chemoselective addition of tetraallyltin to dialkyl, alkenyl-alkyl, and alkynyl-alkyl ketones can be performed with high yields in N-methyl-N-butylpyrrolidinium trifuoromethansulfonate (MBP-Tf). Other room temperature ionic liquids (RTILs) can also be successfully employed if some sulfonic acid is added. The reaction is very sensitive to the electronic properties of the substrate. Aryl alkyl ketones bearing electron-withdrawing substituents behave like dialkyl ketones and react promptly; on the contrary, electron-rich aryl alkyl ketones react sluggishly, which allows selective competitive allylation of dialkyl substrates to occur. The ionic liquid solvent can be easily recycled, which meets the green chemistry principles of selectivity and reuse of chemicals. NMR spectroscopic data support the formation of tin-triflate catalysts in situ.

  2. Mouse model of ulcerative colitis using trinitrobenzene sulfonic acid

    Directory of Open Access Journals (Sweden)

    Irfan Ahmad Rather

    2015-12-01

    Full Text Available Animal model of intestinal inflammation is of paramount significance that aids in discerning the pathologies underlying ulcerative colitis and Crohn’s disease, the two clinical presentations of inflammatory bowel disease. The 2,4,6-trinitrobenzene sulfonic acid (TNBS colitis model represents one such intestinal inflammation-prototype that is generated in susceptible strains of mice through intra-rectal instillation of compound TNBS. In this paper, we demonstrate the experimental induction of TNBS-mediated colitis in a susceptible strain of ICR mice. This can be done by the following steps: a acclimation, b induction and c observation. TNBS-mouse model provides the information in shortest possible time and simultaneously represents a cost effective and highly reproducible model method of studying the pathogenesis of inflammatory bowel disease.

  3. Electronic Conductivity of Polypyrrole−Dodecyl Benzene Sulfonate Complexes

    DEFF Research Database (Denmark)

    West, Keld; Bay, Lasse; Nielsen, Martin Meedom

    2004-01-01

    The electronic conductivity of the electroactive polymer polypyrrole-dodecyl benzene sulfonate (PPy-DBS) has been characterized as function of the redox level. The polymer was synthesized with different isomers of the dopant anions: the common mixed DBS tenside and three well-defined synthetic...... dodecyl isomers (with the benzene group at positions 1, 2 and 6). The conductivity was measured both by van der Pauw measurements on PPy-DBS in the oxidized, dry state as function of temperature, and by electrochemical impedance spectroscopy as function of potential in 0.1 M NaCl aqueous electrolyte...... carriers is at a minimum. The conductivity is further reduced because of the uptake of water at low potentials, creating electrolytic domains that separate the electronic domains and inhibit hopping. There is a pronounced hysteresis in the conductivity as a function of potential. However, the major part...

  4. Sulfonated polyvinyl chloride fibers for cation-exchange microextraction.

    Science.gov (United States)

    Xu, Li; Lee, Hian Kee

    2009-09-18

    Polyvinyl chloride (PVC) fiber was derivatized by concentrated sulfuric acid to yield sulfonated PVC (PVC-SO3H). The PVC-SO3H fiber had dual properties as a sorbent, based on cation-exchange and hydrophobicity. In the present study, the novel fiber was used directly as an individual device for extraction purposes in the cation-exchange microextraction of anaesthetics, followed by high-performance liquid chromatography-UV analysis. The results demonstrated that this PVC-SO3H fiber-based microextraction afforded convenient operation and cost-effective application to basic analytes. The limits of detection for four anaesthetics ranged from 1.2 to 6.0 ng/mL. No carryover (because of its disposable usage), and no loss of sorbent phase (which normally occurs in stir-bar sorptive extraction) during extraction were observed.

  5. Enchansing the Ionic Purity of Hydrophilic Channels by Blending Fully Sulfonated Graft Copolymers with PVDF Homopolymer

    DEFF Research Database (Denmark)

    Nielsen, Mads Møller; Ching-Ching Yang, Ami; Jankova Atanasova, Katja;

    2013-01-01

    The influence of tuning the ionic content of membranes by blending, as opposed to varying the degree of sulfonation, is evaluated. Membranes of fully sulfonated poly(vinylidene fluoride-co-chlorotrifluoroethylene)-g-poly(styrene sulfonic acid) blended with PVDF were prepared and investigated...... for morphology, water sorption, and proton transport properties. The blend membranes exhibit conductivities superior to pure graft copolymers under fully humidified conditions despite their lower water uptake. Transmission electron microscopy images of the blends reveal that the membranes comprise a combination...

  6. Derivatives of phenyl tribromomethyl sulfone as novel compounds with potential pesticidal activity

    Directory of Open Access Journals (Sweden)

    Krzysztof M. Borys

    2012-02-01

    Full Text Available A halogenmethylsulfonyl moiety is incorporated in numerous active herbicides and fungicides. The synthesis of tribromomethyl phenyl sulfone derivatives as novel potential pesticides is reported. The title sulfone was obtained by following three different synthetic routes, starting from 4-chlorothiophenol or 4-halogenphenyl methyl sulfone. Products of its subsequent nitration were subjected to the SNAr reactions with ammonia, amines, hydrazines and phenolates to give 2-nitroaniline, 2-nitrophenylhydrazine and diphenyl ether derivatives. Reduction of the nitro group of 4-tribromomethylsulfonyl-2-nitroaniline yielded the corresponding o-phenylenediamine substrate for preparation of structurally varied benzimidazoles.

  7. Laser photolysis of interaction of poly-guanylic acid (5′) with anthraquinone-2-sulfonate

    Institute of Scientific and Technical Information of China (English)

    马建华; 林维真; 王文峰; 韩镇辉; 姚思德; 林念芸

    2002-01-01

    The electron transfer reaction between triplet anthraquinone-2-sulfonate and poly- guanylic acid (5′) in CH3CN-H2O (97:3) has been investigated by 248 nm (KrF) laser flash photolysis. The transient absorption spectra and kinetics obtained from the interaction of triplet anthraquinone-2-sulfonate and poly[G] demonstrate that the primary ionic radical pair, radical cation of poly[G] and radical anion of anthraquinone-2-sulfonate have been detected simultaneously. The free energy changes in the process of the electron transfer were also calculated.

  8. Sterically Stabilized Poly(3,4-ethylenedioxythiophene) Colloidal Dispersions Doped with Different Sulfonic Acids

    Institute of Scientific and Technical Information of China (English)

    Tie Jun WANG; Ping CHEN; Xiu Jie HU; Shu Yun ZHOU

    2006-01-01

    The preparation of sterically stabilized poly(3, 4-ethylenedioxythiophene)(PEDOT)colloidal dispersions doped with different sulfonic acids is described. Three different sulfonic acids, i.e., p-toluenesulfonic acid, β-naphthalenesuffonic acid and D-camphor-10-sulfonic acid are used, facilitating the preparation of sterically stable PEDOT colloidal particles. The influences of the dopants and concentration of polymeric stabilizer on the yields, morphologies and electrical properties of the resultant colloidal particles were investigated. The colloidal particles with the size ranging from 172 to 334 nm have been obtained in good yields. The compressed pellet conductivity was as high as 4.5 Scm-1.

  9. Synthesis and characterization of quaternized poly(phthalazinone ether sulfone ketone) for anion-exchange membrane

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Chloromethylated poly(phthalazinone ether sulfone ketone) (CMPPESK) was prepared from poly(phthalazinone ether sulfone ketone) (PPESK) using chloromethyl octyl ethers (CMOE) with lower toxicity as chloromethylated regent. CMPPESK was soluble in N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMAc) and chloroform. Quatemized poly(phthalazinone ether sulfone ketone) (QAPPESK) was prepared from CMPPESK by quaternization. QAPPESK had excellent solvent resistance,which was only partly soluble in sulfuric acid (98%) and swollen in N,N-dimethylformamide (DMF). The vanadium redox flow battery (V-RFB) using QAPPESK anion-exchange membrane had better performance with 88.3% of overall energy efficiency.

  10. Laser photolysis of interaction of poly-guanylic acid (5’) with anthraquinone-2-sulfonate

    Institute of Scientific and Technical Information of China (English)

    马建华; 韩镇辉; 林维真; 姚思德; 王文峰; 林念芸

    2002-01-01

    The electron transfer reaction between triplet anthraquinone-2-sulfonate and poly-guanylic acid (5’) in CH3CN-H2O (97 : 3) has been investigated by 248 nm (KrF) laser flash photolysis. The transient absorption spectra and kinetics obtained from the interaction of triplet anthraquinone-2-sulfonate and poly[G] demonstrate that the primary ionic radical pair, radical cation of poly[G] and radical anion of anthraquinone-2-sulfonate have been detected simultaneously. The free energy changes in the process of the electron transfer were also calculated.

  11. Coupling chemical oxidation and biostimulation: Effects on the natural attenuation capacity and resilience of the native microbial community in alkylbenzene-polluted soil.

    Science.gov (United States)

    Martínez-Pascual, Eulàlia; Grotenhuis, Tim; Solanas, Anna M; Viñas, Marc

    2015-12-30

    Coupling chemical oxidation with bioremediation could be a cost-effective system to cope with soil and groundwater pollution. However, the effects of chemical oxidation on autochthonous microbial communities are scarcely known. A detailed analysis that considers both the efficiency of the two technologies and the response of the microbial communities was performed on a linear alkylbenzene-polluted soil and groundwater samples. The impacts of a modified Fenton's reaction (MFR) at various dosages and of permanganate on the microbiota over 4 weeks were assessed. The permanganate and MFR negatively affected microbial abundance and activity. However, the resilience of certain microbial populations was observed, with a final increase in potential hydrocarbon-degrading populations as determined by both the alkB gene abundance and the predominance of well-known hydrocarbon-degrading phylotypes such as Rhodococcus, Ochrobactrum, Acinetobacter and Cupriavidus genera as determined by 16S rRNA-based DGGE fingerprinting. The assessment of the chemical oxidant impact on autochthonous microbiota should be considered for the optimization of coupled field remediation technologies.

  12. Las redes sociales presentes en las bibliotecas

    Directory of Open Access Journals (Sweden)

    Magda Cecilia Sandí Sandí

    2012-07-01

    Full Text Available El presente artículo pretende evidenciar la importancia del uso de las redes sociales en las bibliotecas como una herramienta y un canal de comunicación entre el bibliotecólogo y la comunidad de usuarios. Las redes sociales son una nueva forma de comunicarnos entre las y los usuarios del Internet, su uso es irrestricto y cada vez aumenta la comunidad de usuarios de estas herramientas en la red.

  13. Las redes sociales presentes en las bibliotecas

    Directory of Open Access Journals (Sweden)

    Magda Cecilia Sandí S.

    2012-01-01

    Full Text Available El presente artículo pretende evidenciar la importancia del uso de las redes sociales en las bibliotecas como una herramienta y un canal de comunicación entre el bibliotecólogo y la comunidad de usuarios. Las redes sociales son una nueva forma de comunicarnos entre las y los usuarios del Internet, su uso es irrestricto y cada vez aumenta la comunidad de usuarios de estas herramientas en la red.

  14. The Performance of Advanced Sequencing Batch Reactor in Wastewater Treatment Plant to Remove Organic Materials and Linear Alkyl Benzene Sulfonates

    Directory of Open Access Journals (Sweden)

    Eslami

    2015-07-01

    Full Text Available Background Linear alkyl benzene sulfonates (LAS are the most important ionic detergents that produce negative ions in the environment. These compounds enter surface waters through domestic and industrial wastewaters and cause environmental hazards. Objectives The present study was aimed at assessing the performance of advanced sequencing batch reactor (SBR in wastewater treatment plant of Yazd, Iran, to remove organic materials and detergents. Materials and Methods The present research was a descriptive longitudinal study conducted on 96 input and output samples of SBR system over eight months from October 2012 to June 2013. The studied parameters were biochemical oxygen demand 5 (BOD5, chemical oxygen demand (COD, and detergents (LAS, which were assessed through standard methods. Finally, the study data were analyzed through analysis of variance (ANOVA using software package for statistical analysis (SPSS. Results The mean inputs of BOD5, COD, and LAS to the SBR system were 292.40 ± 45.28, 597.15 ± 97.30, and 3.29 ± 0.92 mg/L, and the mean outputs were 20.59 ± 3.54, 59.34 ± 9.47, and 0.606 ± 0.09 mg/L, respectively. The removal efficiency of BOD5, COD and LAS were respectively 92.95%, 90.06% and 81.6%. The results of ANOVA indicated that there was a significant relationship between the mean inputs and outputs of BOD5, COD, and the detergents (P ≤ 0.001. Conclusions With the proper operation of wastewater the treatment plant and increasing the retention time, the removal efficiency of the detergents increased. In addition, according to the environmental standards for BOD5, COD and the detergents, the results of the present study indicated that the outputs of these parameters from the SBR system were appropriate for agricultural irrigation.

  15. Surface modification of carbon fibers by a polyether sulfone emulsion sizing for increased interfacial adhesion with polyether sulfone

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Haojie [National Engineering Laboratory for Carbon Fiber Technology, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Zhang, Shouchun, E-mail: zschun@sxicc.ac.cn [National Engineering Laboratory for Carbon Fiber Technology, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001 (China); Lu, Chunxiang [National Engineering Laboratory for Carbon Fiber Technology, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001 (China)

    2014-10-30

    Highlights: • A polyether sulfone emulsion (PES) sizing was prepared for the first time. • The sizing enhanced the surface activity and wettability of carbon fibers. • Compared to the original sizing, the PES emulsion sizing resulted in an 18.4% increase in the interlaminar shear strength of carbon fiber/PES composites. • Important influences of emulsifier on the fiber surface and composite interface were demonstrated. • The reinforcing mechanisms are the improved fiber surface wettability and interfacial compatibility in composites. - Abstract: Interests on carbon fiber-reinforced thermoplastic composites are growing rapidly, but the challenges with poor interfacial adhesion have slowed their adoption. In this work, a polyether sulfone (PES) emulsion sizing was prepared successfully for increased interfacial adhesion of carbon fiber/PES composites. To obtain a high-quality PES emulsion sizing, the key factor, emulsifier concentration, was studied by dynamic light scattering technique. The results demonstrated that the suitable weight ratio of PES to emulsifier was 8:3, and the resulting PES emulsion sizing had an average particle diameter of 117 nm and Zeta potential of −52.6 mV. After sizing, the surface oxygen-containing functional groups, free energy and wettability of carbon fibers increased significantly, which were advantageous to promote molecular-level contact between carbon fiber and PES. Finally, short beam shear tests were performed to evaluate the interfacial adhesion of carbon fiber/PES composites. The results indicated that PES emulsion sizing played a critical role for the enhanced interfacial adhesion in carbon fiber/PES composites, and a 26% increase of interlaminar shear strength was achieved, because of the improved fiber surface wettability and interfacial compatibility between carbon fiber and PES.

  16. Derivatization of enolic OH of piroxicam: a comparative study on esters and sulfonates

    Energy Technology Data Exchange (ETDEWEB)

    Jayaselli, J.; Cheemala, J. Manila Sagar; Geetha Rani, D.P.; Pal, Sarbani [MNR Post Graduate College, Kukatpally, Hyderabad (India). Dept. of Chemistry]. E-mail: sarbani277@yahoo.com

    2008-07-01

    A number of ester and sulfonate derivatives of piroxicam were prepared via acylation/sulfonation of the enolic OH of piroxicam. All the compounds were evaluated for their chemical stability and cyclooxygenase inhibiting properties. Data suggested that esters could be useful for the development of potential prodrugs. The sulfonate derivatives prepared for the first time were found to be stable. One of them showed a moderately selective COX-2 inhibition over COX-1 and would have lower gastrointestinal side effects than piroxicam due to the masked enolic OH group. A plausible mechanism for the acylation/sulfonation process has been proposed that involves participation of the pyridine moiety of piroxicam. Molecular structure of one of the ester was established for the first time by the crystal structure analysis from X-ray powder data. (author)

  17. Nonaqueous preparation of stable silver nano particles dispersions from organic sulfonic acids.

    Directory of Open Access Journals (Sweden)

    Valentina Glushko

    2016-05-01

    Full Text Available The conditions for stable silver nano particles dispersions synthesis from organic sulfonic acids in an anhydrous medium of ethylene glycol and its methyl ester were studied. Ascorbic acid and potassium citrate were used as reducing agents.

  18. Synthesis of sulfonated oxindoles by potassium iodide catalyzed arylsulfonylation of activated alkenes with sulfonylhydrazides in water.

    Science.gov (United States)

    Li, Xiaoqing; Xu, Xiangsheng; Hu, Peizhu; Xiao, Xuqiong; Zhou, Can

    2013-07-19

    A catalytic system consisting of KI, 18-crown-6, and TBHP for arylsulfonylation of activated alkenes with sulfonylhydrazides as sulfonyl precursor is described. This protocol provides a practical and environmentally benign method for the construction of sulfonated oxindoles in water.

  19. Preparation of a Sulfonated Carbonaceous Material from Lignosulfonate and Its Usefulness as an Esterification Catalyst

    Directory of Open Access Journals (Sweden)

    Duckhee Lee

    2013-07-01

    Full Text Available Sulfonated carbonaceous material useful as a solid acid catalyst was prepared from lignosulfonate, a waste of the paper-making industry sulfite pulping process, and characterized by 13C-NMR, FT-IR, TGA, SEM and elemental analysis, etc. The sulfonic acid group density and total density of all acid groups in the sulfonated carbonaceous material was determined by titration to be 1.24 mmol/g and 5.90 mmol/g, respectively. Its catalytic activity in the esterification of cyclohexanecarboxylic acid with anhydrous ethanol was shown to be comparable to that of the ionic exchange resin Amberlyst-15, when they were used in the same amount. In the meantime, the sulfonic acid group was found to be leached out by 26%–29% after it was exposed to hot water (95 °C for 5 h. The catalytic usefulness of the prepared carbonaceous material was investigated by performing esterifications.

  20. Synthesis and characterization of novel sulfonated polyimide containing phthalazinone moieties as PEM for PEMFC

    Institute of Scientific and Technical Information of China (English)

    Hai Yan Pan; Yong Fang Liang; Xiu Ling Zhu; Xi Gao Jian

    2007-01-01

    A novel sulfonated diamine monomer, 1,2-dihydro-2-(3-sulfonic-4-aminophenyl)-4-[4-(4-aminophenoxy)-phenyl]phthalazin1-one (S-DHPZDA), was successfully synthesized by direct sulfonation of diamine 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)-phenyl]-phthalazin- 1-one (DHPZDA). A series of sulfonated polyimides (SPIs), which can be used as the material of the proton exchange membrane (PEM) for the proton exchange membrane fuel cell (PEMFC), were prepared from 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA), S-DHPZDA, and nonsulfonated diamines DHPZDA. The structure of the monomer and polymers were characterized by FT-IR and 1H NMR. The solubility of the S-DHPZDA-based SPIs has been improved due to the induction of the phthalazione moiety. The SPIs membranes have high thermo-stability, predominant swelling resistance with high ion exchange capacity.

  1. Sulfonyl Imidazoles as Reagents for the Preparation of Sulfonates and Sulfonamides

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Several new sulfonates and sulfonamides were synthesized with sulfonyl imidazoles as reagents. These compounds were characterized by 1H NMR. The melting points of all solids synthesized were obtained on Fisher-Johns Melting Point Apparatus.

  2. Photoinduced Electron Transfer Reaction between Poly-guanylic Acid (5`) with Anthraquinone-2-sulfonate

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The electron transfer reaction between triplet anthraquinone-2-sulfonate with poly-guanylic acid (5) (poly[G]) in acetonitrile-H2O has been investigated by 248 nm laser flash photolysis. The transient absorption spectra of radical cation of poly[G] and radical anion of anthraqunione-2-sulfonate(AQS) arising from electron transfer reaction has been observed simultaneously for the first time. The formation processes of radical cation of poly[G] and radical anion of anthraquinone-2-sulfonate as well as the decay processes of triplet anthraquinone-2-sulfonate have also been observed, the apparent rate constants for the formation and decay of transient species have been determined. The free energy changes in the process of the electron transfer was also calculated.

  3. Colonic necrosis and perforation due to calcium polystyrene sulfonate in a uraemic patient: a case report

    OpenAIRE

    Akagun, Tulin; Yazici, Halil; Gulluoglu, Mine G.; Yegen, Gulcin; Turkmen, Aydin

    2011-01-01

    Sodium or calcium polystyrene sulfonate (Kayexalate or analog) is an ion-exchange resin commonly used to treat hyperkalaemia in patients with chronic kidney disease. It is known to cause digestive complications, such as nausea, vomiting and constipation. Although rare, colonic necrosis and perforation are very severe complications associated with the medication. In this case report, we present a case of calcium polystyrene sulfonate-induced colonic necrosis and perforation to remind clinician...

  4. Asymmetrical Self-assembly From Fluorinated and Sulfonated Block Copolymers in Aqueous Media

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaojun [ORNL; Hong, Kunlun [ORNL; Baskaran, Durairaj [University of Tennessee, Knoxville (UTK); Goswami, Monojoy [ORNL; Sumpter, Bobby G [ORNL; Mays, Jimmy [ORNL

    2011-01-01

    Block copolymers of fluorinated isoprene and partially sulfonated styrene form novel tapered rods and ribbon-like micelles in aqueous media due to a distribution of sulfonation sites and a large Flory-Huggins interaction parameter. A combination of microscopy, light scattering, and simulation demonstrates the presence of these unique nanostructures. This study sheds light on the micellization behavior of amphiphilic block polymers by revealing a new mechanism of self-assembly.

  5. Unusual Cycloadducts from the Dipolar Cycloaddition of Allenyl Perfluoroalkyl Sulfones to Nitrones

    Institute of Scientific and Technical Information of China (English)

    WANG,Xiao-Jin; LIU,Jin-Tao

    2007-01-01

    The dipolar cycloaddition reaction of allenyl perfluoroalkyl sulfones (1) to nitrones (2) was described. Unlike nonfluorine-containing allenyl sulfones, 1 reacted readily with 2 in ether at room temperature and unusual zwitterionic cycloadducts (3) were obtained in good yields due to the strong electron-withdrawing effect of perfluoroalkyl groups. The structure of 3 was characterized by spectral analyses and X-ray crystallography.

  6. Activated-sludge nitrification in the presence of linear and branched-chain alkyl benzene sulfonates.

    Science.gov (United States)

    Baillod, C R; Boyle, W C

    1968-01-01

    The effects of biodegradable linear alkyl benzene sulfonate and branched-chain alkyl benzene sulfonate detergents on activated-sludge nitrification were investigated by administering a synthetic waste containing up to 23 mg of each detergent per liter to eight bench-scale, batch, activated-sludge units. It was found that both detergents tended to promote complete oxidation of ammonia to nitrate, whereas control units produced approximately equal amounts of nitrite and nitrate. Various hypotheses are offered to explain the phenomenon.

  7. Composite proton exchange membrane based on sulfonated organic nanoparticles

    Science.gov (United States)

    Pitia, Emmanuel Sokiri

    As the world sets its sight into the future, energy remains a great challenge. Proton exchange membrane (PEM) fuel cell is part of the solution to the energy challenge because of its high efficiency and diverse application. The purpose of the PEM is to provide a path for proton transport and to prevent direct mixing of hydrogen and oxygen at the anode and the cathode, respectively. Hence, PEMs must have good proton conductivity, excellent chemical stability, and mechanical durability. The current state-of-the-art PEM is a perfluorosulfonate ionomer, Nafion®. Although Nafion® has many desirable properties, it has high methanol crossover and it is expensive. The objective of this research was to develop a cost effective two-phase, composite PEM wherein a dispersed conductive organic phase preferentially aligned in the transport direction controls proton transport, and a continuous hydrophobic phase provides mechanical durability to the PEM. The hypothesis that was driving this research was that one might expect better dispersion, higher surface to volume ratio and improved proton conductivity of a composite membrane if the dispersed particles were nanometer in size and had high ion exchange capacity (IEC, = [mmol sulfonic acid]/gram of polymer). In view of this, considerable efforts were employed in the synthesis of high IEC organic nanoparticles and fabrication of a composite membrane with controlled microstructure. High IEC, ~ 4.5 meq/g (in acid form, theoretical limit is 5.4 meq/g) nanoparticles were achieved by emulsion copolymerization of a quaternary alkyl ammonium (QAA) neutralized-sulfonated styrene (QAA-SS), styrene, and divinylbenzene (DVB). The effects of varying the counterion of the sulfonated styrene (SS) monomer (alkali metal and QAA cations), SS concentration, and the addition of a crosslinking agent (DVB) on the ability to stabilize the nanoparticles to higher IECs were assessed. The nanoparticles were ion exchanged to acid form. The extent of ion

  8. Viscoelastic Behavior of Low Molecular Weight Sulfonated Polystyrene Ionomers

    Science.gov (United States)

    Zhao, Hongying

    Ionomers are those hydrophobic polymers having small amounts of bonded ionic groups. The introduction of the ionic groups into polymer chain produces large changes in the physical, mechanical and rheological properties of the parent polymer. Characterization of the effect of the ionic interactions on the rheology is complicated by the difficulty in separating effects due to molecular entanglements and the ionic interactions. In this study, low molecular weight (Mw=4000) sulfonated polystyrene (SPS) was used to study the dynamic and steady shear rheology of SPS ionomers. The polymer chain length used was far below the entanglement molecular weight of polystyrene and effects of molecular entanglements will be absent. Any polymer chain entanglements or lengthening behavior on the melt rheology should be due to the ionic interactions. Random SPS ionomers with two sulfonation levels were examined, 2.5 and 4.8 mol%, which corresponded, respectively, to one and two sulfonate groups per chain on average. The metal counterions was varied across the alkali metal series of the periodic table. Morphology of the ionomer was characterized by using small angle x-ray scattering (SAXS) analysis, and dynamic and steady shear measurements were performed to investigate rheological behavior of the ionomers. Glass transition temperatures of the ionomers increased with increasing ion concentration but were insensitive to cation used. The scattering peak in SAXS indicates the existence of the nanophase separated ionic clusters. The strong ionic nanophase persist up to very high temperatures and is not sensitive to the external stress. Time-temperature superposition (TTS) of G' worked reasonably well while TTS of G" failed for most ionomers. Ionic interactions increased the terminal relaxation time of the melts as much as seven orders of magnitude greater than the unentangled PS melt. The zero shear viscosity and first normal stress coefficients scaled with cq/a, where c was the

  9. Semiquantitative evaluation of fibronectin adsorption on unmodified and sulfonated polystyrene, as related to cell adhesion.

    Science.gov (United States)

    Kowalczyńska, Hanna M; Nowak-Wyrzykowska, Małgorzata; Kołos, Robert; Dobkowski, Jacek; Kamiński, Jarosław

    2008-12-15

    The process of human fibronectin (FN) adsorption on nonsulfonated and sulfonated polystyrene surfaces was studied in relation to mechanisms of L1210 cell adhesion. Radioisotope assays directed towards FN, as well as ELISA measurements of adsorbed FN and bovine serum albumin (BSA) were carried out. (125)I radioisotope assays led to linear FN adsorption isotherms. When combined to ELISA measurements for FN, they revealed the multilayer adsorption. Results indicated a large difference in the saturating first-layer surface density of FN adsorbed on sulfonated and nonsulfonated polystyrene surfaces: significantly (ca. factor of 5) less FN molecules are necessary to complete a monolayer on sulfonated than on nonsulfonated polystyrene. This suggests an unfolded conformation of FN on sulfonated polystyrene, and a more compact one on the nonsulfonated polymer. Significant conformational changes of FN are also indicated by the following: (1) early phase of cell adhesion to FN adsorbed on sulfonated polystyrene surfaces is significantly (ca. factor of 6) higher than to FN on nonsulfonated surfaces, and in the former case adhesion proceeds mostly via alpha(5)beta(1) integrins; (2) RGD, the crucial fragment within central cell binding domain, seems to be partially hidden in the protein structure adopted on nonsulfonated surfaces; (3) patterns of F-actin organization differ in cells adhering to FN on sulfonated and nonsulfonated surfaces. The ELISA study directed against BSA (this protein always present on the surface after the adsorption of FN), showed the importance of "free area," uncovered by both proteins, which influence the cell adhesion processes.

  10. Single-step synthesis of sulfonated polyoxadiazoles and their use as proton conducting membranes

    Science.gov (United States)

    Gomes, Dominique; Roeder, Jerusa; Ponce, Mariela L.; Nunes, Suzana P.

    A single-step approach for the synthesis of sulfonated polyoxadiazoles from hydrazine sulfate was developed using non-sulfonated diacids in polyphosphoric acid. The post-sulfonation conditions were optimized by varying reaction time, medium and reagent concentrations in sulfuric acid, oleum and/or their mixtures. For the first time, a series of sulfonated polyoxadiazoles with ion exchange capacity (IEC) ranging from 1.26 to 2.7 meqiv. g -1 and high molecular weight (about 40,0000 g mol -1) were synthesized. The structures of the polymers were characterized by elemental analysis, 1H NMR, and FTIR. Sulfonated polyoxadiazole membranes with high thermal stability indicated by observed glass-transition temperatures (T g) ranging from 364 to 442 °C in sodium salt form and from 304 to 333 °C in acid form and with high mechanical properties (storage modulus about 3 GPa at 300 °C) have been prepared. The membrane stability to oxidation was investigated by soaking the film in Fenton's reagent at 80 °C for 1 h. The sulfonated polyoxadiazole membranes exhibited high oxidative stability, retaining 98-100% of their weight after the test. Proton conductivity values with the order of magnitude of 10 -1 to 10 -2 S cm -1 at 80 °C and with relative humidity ranging from 100% to 20% were obtained.

  11. Morphogenetic control of calcite crystal growth in sulfonic acid based hydrogels.

    Science.gov (United States)

    Grassmann, Olaf; Löbmann, Peer

    2003-03-17

    In this paper the mineralization of CaCO(3) in various hydrogel matrices is presented. Sulfonic acid based hydrogels were prepared by introduction of sulfonate-containing monomers into a polyacrylamide network. The sulfonate content of polyacrylamide-co-vinylsulfonate and polyacrylamide-co-allylsulfonate decreases during elution of the copolymers in demineralized water, indicating insufficient linking of the sulfonate-bearing monomers within the hydrogel. In contrast to this, acrylamidomethylpropanesulfonate (AMPS) effectively copolymerizes with acrylamide (AAm) monomers. To study the influence of spatial arrangement of ionic functional groups within hydrogel networks on the mineralization of CaCO(3), AMPS copolymers with different degrees of AMPS cross-linking were synthesized. For the mineralization experiments the copolymers were placed into a double-diffusion arrangement. Calcite as the thermodynamically stable modification of CaCO(3) was obtained with a particular morphology. The pseudocubic habitus resembles aggregates obtained by mineralization in pure polyacrylamide. However, closer examination of the aggregates by scanning electron microscopy (SEM) shows that the crystal growth in the AMPS copolymers is different from that observed in polyacrylamide. Whereas the morphology of the calcite aggregates could be fine-tuned by using copolymers with different sulfonate content, the spatial distribution of the ionic functional groups alters the course of crystallization. Calcium ions are locally accumulated due to the heterogeneous distribution of functional sulfonate groups within the copolymer network. Thereby the nucleation of calcite is triggered, resulting in enhanced mineralization.

  12. Radiation-induced crosslinking of poly(styrene-butadiene-styrene) block copolymers and their sulfonation

    Science.gov (United States)

    Lee, Sun-Young; Song, Ju-Myung; Sohn, Joon-Yong; Shul, Yong-Gun; Shin, Junhwa

    2013-12-01

    Several crosslinked poly(styrene-butadiene-styrene) (c-SBS) block copolymer films were prepared using a gamma ray or electron beam with various irradiation doses and the prepared c-SBS film was then subjected to sulfonation using a chlorosulfonic acid (CSA) solution to introduce a sulfonic acid group. To estimate the degree of crosslinking, the gel fractions and FT-IR spectra of the c-SBS films were used and the results indicate that the degree of crosslinking is increased with an increase in the radiation dose. The surface morphology and mechanical property of the c-SBS films were observed using SEM and UTM instruments, respectively. The sulfonated c-SBS films were investigated by measuring the ion exchange capacity (IEC) and by observing the cross-sectional distribution patterns of sulfonic acid group using an SEM-EDX instrument. The IEC and SEM-EDX studies indicate that the sulfonated c-SBS membranes can be successfully prepared through the radiation crosslinking of the SBS film and the subsequent sulfonation with a diluted CSA solution.

  13. Study on the toxicity of LAS to male mice and male offspring spermatogenic function%LAS对雄性小鼠及其子代生精功能毒性作用的研究

    Institute of Scientific and Technical Information of China (English)

    韩海艳; 任春娥; 乔鹏云; 姜俊怡; 张茂翔

    2013-01-01

    Objective:To study the toxicities impact of the linear alkylbenzene sulfonates on the male mice and offspring male reproductive function.Methods:All of the 120 Kunming male mice were divided into four groups randomly and every group was 30.Group A was treated P.O.with LAS 630mg/kg,one time per day,for eight weeks and then mated with female mice (the proportion was 1∶1).Group B was treated P.O.with LAS 630mg/kg,one time per day,for eight weeks and stopped treating for 4 weeks,then mated with female mice (the proportion was 1 ∶ 1).Both of the male mice of the group A and group B were pulled neck to death after mating.Group a and group b were the contrast groups of group A and group B separately.They were treated with physiological saline solution and pulled neck to death after mating.The offspring male mice of the group A,B,a,b was group A1,B1,a1,b1 separately and pulled neck to death when they growed upto 6 ~ 8 weeks.The weight of the body and testicle,concentration and vitality of sperm,sperm forms,histophthology and electron transmission microscopy of the testis were assayed.Results:Compared with the controls,lower of sperm concentration and vitality and higher malformation were obvious.The histology revealed that each spermatocytes and spermids obviously reduced,spermatogenic cells arranged chaoticly.Determination revealed that the morphology of mitochondria in spermospore,leydig cells and sertoli cells from the experimental group showed a greater variance than that in mice from the control group.Furthermore,there showed no obvious recovery of all the morphological abnormalities after be stopped treating with LAS for 4 weeks.Conclusion:LAS has evident toxicities impact on the male animals reproductive function,and the damage the LAS has made could not recovery in a short time.%目的:探讨十二烷基苯磺酸钠(LAS)对雄性小鼠及其子代雄性小鼠生精功能的毒性作用.方法:将120只昆明种雄性小鼠随机分为4组,每组30只.实验A

  14. Fire Fighter Trainer Environmental Considerations. Phase II.

    Science.gov (United States)

    1981-07-31

    Tergitol NP-9 (Union Carbide) - Tergitol NP-10 (Union Carbide) Linear alkylbenzene sulfonates - Ultrawet K (Arco) - Nacconol 35 SL (Stepan) Polyethylene...environment. The sulfonic acids (and salts) were also preliminarily acceptable according to the criteria. We selected the subclass of alkylbenzene sulfonates ...salts) - 552 million 1pounds Carboxylic acids (and their salts) - 878 million pounds i . Sulfonic acids (and their salts) - 1.6 billion pounds

  15. An investigation of proton conductivity of binary matrices sulfonated polysulfone/polyvinyltriazole after doping with inorganic acids

    Indian Academy of Sciences (India)

    Serkan Sevinç; Sevim Ünügür Çelik; Ayhan Bozkurt

    2015-04-01

    As anhydrous proton conductive membranes, sulfonated polysulfone (SPSU) and polyvinyl triazole were studied as binary matrices. The sulfonation of polysulfone was performed with trimethylsilylchlorosulfonate and high degree of sulfonation (140%) was obtained. Ion exchange capacity of SPSU was determined as 3.05 mmol−1/g. The polymer electrolyte membranes were prepared by blending of sulfonated polysulfone with polyvinyl triazole and phosphoric acid. Fourier transform infrared spectroscopy confirmed the sulfonation of the polysulfone and the ionic interaction between sulfonic acid and triazole units. Thermogravimetric analysis showed that the polymer electrolyte membranes are thermally stable up to at least 150° C. Scanning electron microscopy analysis indicated the homogeneity of the ternary composites. The maximum proton conductivity has been measured as 3.63 × 10−4S cm−1 at 150° C.

  16. SYNTHESIS AND PROPERTIES OF SULFONATED POLY(ARYLENE ETHER) CONTAINING TRIPHENYL METHANE MOIETIES FROM ISOCYNATE MASKED BISPHENOL

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A novel sulfonated poly(arylene ether) containing triphenylmethane moieties was synthesized by the sulfonation of a designed parent polymer using chlorosulfonic acid as sulfonation agent. The sulfonation took place at the para position of the pendant phenyl rings because of the specially designed parent polymer. The position and degree of sulfonation were characterized by 1H-NMR and elemental analysis. The sulfonated polymers are highly soluble in common organic solvents, such as dimethylsulfoxide, N,N'-dimethylacetamide, dimethylformamide, ethylene glycol monomethyl ether, and can be readily cast into tough and smooth films from solutions. The films showed good thermal and hydrolysis stabilities. Moreover, Fenton's reagent test revealed that the films exhibited superior stability to oxidation. The proton conductivities of the films were comparable with Nation 117 under same conditions. The membrane electrode assembly (MEA) prepared with the asmade film (706 EW, 100 μm dry thickness) shows better cell performance than Nation 115-MEA in the whole current density range.

  17. Sorption and desorption of dyes by sulfonated coal

    Energy Technology Data Exchange (ETDEWEB)

    Mittal, A.K. (Motilal Nehru Regional Coll. of Engineering, Allahabad (India)); Venkobachar, C. (Indian Inst. of Tech., Kanpur (India))

    Wastewaters from dye-manufacturing factories and textile, paper, and pulp industries are highly colored. Their discharge into river waters make the water inhibitory to aquatic life, aside from causing, visible pollution. Dyes have a tendency to sequester metals, thus causing microtoxicity to fish and other aquatic organisms. A wide variety of low-cost materials such as flyash, clay minerals, coal, tire chippings, coconut shell powder and biosorbents are being tried as viable substitutes for activated carbon to remove different pollutants such as pesticides, heavy metals, and dyes. The removal of dyes depends upon their physical and chemical characteristics, as well as the properties of the selected sorbents. To understand the nature of the chemical bonding between dyes and sorbents during the sorption process, it is essential to conduct desorption studies. The reversibility of adsorption of dyes can also be determined by a simple mathematical equation. These studies provide information on whether or not the sorbent material can be regenerated after exhaustion. The present study focuses on sorption-desorption of dyes by sulfonated coal, whose dye sorption potential was established by Mittal and Venkobachar (1990).

  18. Chronic perfluorooctane sulfonate (PFOS) exposure induces hepatic steatosis in zebrafish

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Jiangfei; Lv, Suping; Nie, Shangfei; Liu, Jing; Tong, Shoufang; Kang, Ning; Xiao, Yanyan; Dong, Qiaoxiang [Zhejiang Provincial Key Laboratory for Technology and Application of Model Organisms (China); Institute of Environmental Safety and Human Health, Wenzhou Medical University, Wenzhou, 325035 (China); Huang, Changjiang, E-mail: cjhuang5711@163.com [Zhejiang Provincial Key Laboratory for Technology and Application of Model Organisms (China); Institute of Environmental Safety and Human Health, Wenzhou Medical University, Wenzhou, 325035 (China); Yang, Dongren, E-mail: yangdongren@yahoo.com [Zhejiang Provincial Key Laboratory for Technology and Application of Model Organisms (China); Institute of Environmental Safety and Human Health, Wenzhou Medical University, Wenzhou, 325035 (China)

    2016-07-15

    Highlights: • PFOS chronic exposure induces sex-dependent hepatic steotosis in zebrafish. • PFOS interferes with β-oxidation, lipid synthesis, and lipid hepatic export process. • Zebrafish could be used as an alternative model for PFOS chronic toxicity screening. - Abstract: Perfluorooctane sulfonate (PFOS), one persistent organic pollutant, has been widely detected in the environment, wildlife and human. Currently few studies have documented the effects of chronic PFOS exposure on lipid metabolism, especially in aquatic organisms. The underlying mechanisms of hepatotoxicity induced by chronic PFOS exposure are still largely unknown. The present study defined the effects of chronic exposure to low level of PFOS on lipid metabolism using zebrafish as a model system. Our findings revealed a severe hepatic steatosis in the liver of males treated with 0.5 μM PFOS as evidenced by hepatosomatic index, histological assessment and liver lipid profiles. Quantitative PCR assay further indicated that PFOS significantly increase the transcriptional expression of nuclear receptors (nr1h3, rara, rxrgb, nr1l2) and the genes associated with fatty acid oxidation (acox1, acadm, cpt1a). In addition, chronic PFOS exposure significantly decreased liver ATP content and serum level of VLDL/LDL lipoprotein in males. Taken together, these findings suggest that chronic PFOS exposure induces hepatic steatosis in zebrafish via disturbing lipid biosynthesis, fatty acid β-oxidation and excretion of VLDL/LDL lipoprotein, and also demonstrate the validity of using zebrafish as an alternative model for PFOS chronic toxicity screening.

  19. Perfluorooctane sulfonate (PFOS) induced embryotoxicity and disruption of cardiogenesis.

    Science.gov (United States)

    Cheng, Wei; Yu, Zhuo; Feng, Lixin; Wang, Yan

    2013-08-01

    Prenatal exposure to perfluorooctane sulfonate (PFOS) is correlated with birth defects and adverse health effects. However, the mechanisms remain largely unknown. In current study, the embryonic stem cell test (EST) was performed to evaluate the embryotoxicity of PFOS, and embryonic stem cells (ESCs)-derived cardiomyocytes were used as a model of the early stages of heart development to determine the developmental toxicity of PFOS. One validated endpoint and three molecular endpoints were observed to ensure accurate evaluation of toxicity. According to the criteria of the EST, PFOS was classified as weak embryotoxic. In addition, a cascade of genes related to normal cardiac development was examined at three different time points to monitor cardiogenesis. We found that PFOS significantly interfered with gene expression during cardiogenesis, especially on Nkx2.5 and Myl4. Further, PFOS reduced ATP production in ESCs-derived cardiomyocytes, together with PFOS induced apoptosis, could explain the reduction in beating ability. PFOS-induced reactive oxygen species (ROS) accumulated within cells, which was accompanied by an interfering expression of apoptosis-related genes, ultimately leading to apoptosis. In conclusion, PFOS altered the expression of crucial genes, reduced ATP production, induced ROS, and stimulated apoptosis during the early stages of cardiogenesis; these effects may result in poor developmental outcomes.

  20. Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) contamination from textiles.

    Science.gov (United States)

    Supreeyasunthorn, Phenpimuk; Boontanon, Suwanna K; Boontanon, Narin

    2016-01-01

    The goals of this study were to determine the concentrations of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in textiles and to determine PFOS and PFOA contamination in textile washing water. Quantification analysis was performed by high performance liquid chromatography coupled with tandem mass spectrometry. Analysis of 32 textile samples by methanol extraction revealed that the average concentrations of PFOS and PFOA were 0.18 µg m(-2) (0.02 to 0.61 µg m(-2)) and 2.74 µg m(-2) (0.31 to 14.14 µg m(-2)), respectively. Although the average concentration of PFOS found in textile samples was below European Union (EU) Commission regulations (textile samples had PFOA concentrations exceeding 1 µg m(-2). Thus, based on these results, the concentration of PFOA in products should also be regulated. Experiments on PFOS and PFOA leaching into washing water were conducted. The maximum concentrations of PFOS and PFOA were measured after the first washing; the concentrations gradually decreased with each subsequent washing. PFOS and PFOA migrated from textiles and were released into the environment, with disappearance percentages of 29.8% for PFOS and 99% for PFOA. The data presented in this study showed that textiles could be a significant direct and indirect source of PFOS and PFOA exposure for both humans and the environment.

  1. Amitriptyline, clomipramine, and doxepin adsorption onto sodium polystyrene sulfonate

    Science.gov (United States)

    2014-01-01

    Purpose of the study Comparative in vitro studies were carried out to determine the adsorption characteristics of 3 drugs on activated charcoal (AC) and sodium polystyrene sulfonate (SPS). Activated charcoal (AC) has been long used as gastric decontamination agent for tricyclic antidepressants (TCA). Methods Solutions containing drugs (amitriptyline, clomipramine, or doxepin) and variable amount of AC or SPS were incubated for 30 minutes. Results At pH 1.2 the adsorbent: drug mass ratio varied from 2 : 1 to 40 : 1 for AC, and from 0.4 : 1 to 8 : 1 for SPS. UV–VIS spectrophotometer was used for the determination of free drug concentrations. The qmax of amitriptyline was 0.055 mg/mg AC and 0.574 mg/mg SPS, qmax of clomipramine was 0.053 mg/mg AC and 0.572 mg/mg SPS, and qmax of doxepin was 0.045 mg/mg AC and 0.556 mg/mg SPS. The results of adsorption experiments with SPS revealed higher values for the qmax parameters in comparison with AC. Conclusion In vitro gastric decontamination experiments for antidepressant amitriptyline, clomipramine, and doxepin showed that SPS has higher qmax values than the corresponding experiments with AC. Therefore, we suggest SPS is a better gastric decontaminating agent for the management of acute TCA intoxication. PMID:24450391

  2. Toxicity of perfluorononanoic acid and perfluorooctane sulfonate to Daphnia magna

    Institute of Scientific and Technical Information of China (English)

    Guang-hua Lu; Jian-chao Liu; Li-sha Sun; Lu-jin Yuan

    2015-01-01

    In order to study toxicological effects of perfluorononanoic acid (PFNA), perfluorooctane sulfonate (PFOS), and their mixtures (PFNA/PFOS) on Daphnia magna (D. magna), a suite of comprehensive toxicity tests were conducted, including a 48-h acute toxicity test, a 21-day chronic test, a feeding experiment, and a biomarker assay. D. magna were exposed to aqueous solutions of PFNA and PFOS (alone and in combination) at concentrations ranging from 0.008 to 5 mg/L. The survival, growth, and reproduction of D. magna were monitored over a 21-day life cycle. The biomarkers, including acetylcholinesterase (AChE), superoxide dismutase (SOD), and catalase (CAT) activities, were determined after seven days of exposure. PFOS was more toxic than PFNA based on the results of the acute toxicity test. Perfluorinated compounds (PFCs) inhibited both growth and reproduction of D. magna during the testing period. The ingestion rates and the biomarkers, including AChE, SOD, and CAT activities, were significantly inhibited by PFCs in most cases. Moreover, the combined effects related to the growth and reproduction showed the antagonistic effects of PFCs.

  3. Toxicity of perfluorononanoic acid and perfluorooctane sulfonate to Daphnia magna

    Directory of Open Access Journals (Sweden)

    Guang-hua LU

    2015-01-01

    Full Text Available In order to study toxicological effects of perfluorononanoic acid (PFNA, perfluorooctane sulfonate (PFOS, and their mixtures (PFNA/PFOS on Daphnia magna (D. magna, a suite of comprehensive toxicity tests were conducted, including a 48-hour acute toxicity test, a 21-day chronic test, a feeding experiment, and a biomarker assay. D. magna were exposed to aqueous solutions of PFNA and PFOS (alone and in combination at concentrations ranging from 0.008 to 5 mg/L. The survival, growth, and reproduction of D. magna were monitored over a 21-day life cycle. The biomarkers, including acetylcholinesterase (AChE, superoxide dismutase (SOD, and catalase (CAT activities, were determined after seven days of exposure. PFOS was more toxic than PFNA based on the results of the acute toxicity test. Perfluorinated compounds (PFCs inhibited both growth and reproduction of D. magna during the testing period. The ingestion rates and the biomarkers, including AChE, SOD, and CAT activities, were significantly inhibited by PFCs in most cases. Moreover, the combined effects related to the growth and reproduction showed the antagonistic effects of PFCs.

  4. Nitric Acid Dehydration Using Perfluoro Carboxylate and Mixed Sulfonate/Carboxylate Membranes

    Energy Technology Data Exchange (ETDEWEB)

    Ames, Richard L. [Colorado School of Mines, Golden, CO (United States)

    2004-09-01

    Perfluoro ionomer membranes are tetrafluoro ethylene-based materials with microheterogeneous structures consisting of a hydrophobic polymer backbone and a hydrophilic side-chain cluster region. Due to the ionomer cluster morphology, these films exhibit unique transport properties. Recent investigations with perfluoro sulfonate and perfluoro sulfonate/carboxylate composite polymers have demonstrated their value in the dehydration of nitric acid and they show potential as an alternative to conventional, energy intensive unit operations in the concentration of acid feeds. As a result, investigations were conducted to determine the feasibility of using pure perfluoro carboxylate and mixed perfluoro sulfonate/carboxylate films for the dehydration of nitric acid because of the speculation of improved water selectivity of the carboxylate pendant chain. During the first phase of these investigations the effort was focused on generating a thin, solution cast perfluoro carboxylate ionomer film, to evaluate the general, chemical and physical characteristics of the polymer, and to assess the material's aqueous transport performance (flux and nitrate separation efficiencies) in pervaporation and high-pressure environments. Results demonstrated that generating robust solution-cast films was difficult yet a number of membranes survived high trans-membrane pressures up to 700 psig. General characterization of the solution cast product showed reduced ion exchange capacities when compared with thicker, ''as received'' perfluoro carboxylate and similar sulfonate films. Small angle x-ray scattering analysis results suggested that the solution cast carboxylate films contained a small fraction of sulfonate terminated side-chains. Aqueous transport experimentation showed that permeate fluxes for both pure water and nitric acid were approximately two orders of magnitude smaller for the carboxylate solution cast membranes when compared to their sulfonate

  5. Synthesis and characterization of sulfonated polyesters derived from glycerol; Sintese e caracterizacao de poliesteres sulfonados obtidos a partir do glicerol

    Energy Technology Data Exchange (ETDEWEB)

    Fiuza, R.A.; Jose, N.M.; Boaventura, J.S. [Universidade Federal da Bahia (IQ/UFBA), Salvador, BA (Brazil). Inst. de Quimica; Fiuza, R.P. [Universidade Federal da Bahia (EP/UFBA), Salvador, BA (Brazil). Escola Politecnica. Curso de Mestrado em Engenharia Quimica

    2010-07-01

    In this work were synthesized polyesters from glycerol and acid sulfonated phthalic previously. The materials were characterized by DSC, TGA, FTIR, SEM, XRD and XRF. The results showed effective sulfonation of phthalic acid. The presence of sulfonic groups promoted strong changes in the crystallinity of the new material makes the lens. The polyesters made from phthalic acid sulfonated combine characteristics such as heat resistance and groups that drivers potentiate the electrolyte for application in fuel cells proton exchange membrane and also for gas separation. (author)

  6. Highly Efficient Biomimetic Oxidation of Sulfide to Sulfone by Hydrogen Peroxide in the Presence of Manganese meso-Tetraphenylporphyrin

    Institute of Scientific and Technical Information of China (English)

    ZHOU,Xian-Tai; JI,Hong-Bing; YUAN,Qiu-Lan; XU,Jian-Chang; PEI,Li-Xia; WANG,Le-Fu

    2008-01-01

    Low amount of manganese meso-tetraphenyl porphyrin [Mn(TPP)] was used for highly efficient selective oxidation of sulfide to sulfone by hydrogen peroxide at room temperature.Sulfones were produced directly with yields generally around 90% while the catalyst concentration was only 4 ×10-5 mol·L-1.In a large-scale experiment of thioanisole oxidation,the isolated yield of sulfone (87%) was obtained and the turnover number (TON) reached up to 8×106,which is the highest TON for the oxidation systems of sulfide to sulfone catalyzed by metalloporphyrins.

  7. Phosphoric Acid-Mediated Synthesis of Vinyl Sulfones through Decarboxylative Coupling Reactions of Sodium Sulfinates with Phenylpropiolic Acids.

    Science.gov (United States)

    Rong, Guangwei; Mao, Jincheng; Yan, Hong; Zheng, Yang; Zhang, Guoqi

    2015-08-07

    A novel phosphoric acid -mediated synthesis of vinyl sulfones through decarboxylative coupling reactions of sodium sulfinates with phenylpropiolic acids is described. This transformation is efficient and environmentally friendly.

  8. Molecular dynamics simulation of nanoscale distribution and mobility of water and dimethylmethylphosphonate in sulfonated polystyrene.

    Science.gov (United States)

    Vishnyakov, Aleksey; Neimark, Alexander V

    2008-11-27

    The interest in a better understanding of the specific interactions of phosphor-organic compounds and water with sulfonated polystyrene (sPS) is motivated by the use of block copolymers as protective membranes against chemical warfare agents. Using classical molecular dynamics simulations, we explored the nanoscale segregation and diffusion of water and nerve gas simulant dimethylmethylphosphonate (DMMP) in sPS neutralized with calcium counterions at different sulfonation and hydration levels. The water content was varied from 15 to 54% of dry polymer weight, and the DMMP content was varied from 0 to 100 wt %. We found that, in the 40% sulfonated polystyrene, water forms well defined aggregates, which grow in size as the hydration increases, reaching approximately 20 A at the maximum water content. In the 100% sulfonated polystyrene, the overall structure of hydrated polymer is more uniform with smaller water aggregates. Diffusion of water at the same number of water molecules per sulfonate group is faster at a lower sulfonation level. The solvation of sPS in water-DMMP binary mixtures was found to differ substantially from Nafion, where DMMP forms a layer between the hydropholic and hydrophobic subphases. In sPS with divalent Ca(2+) counterions, DMMP and water compete for the solvation of the sulfonate group. At high water and DMMP contents, the diffusion of DMMP turned out to be rather fast with a diffusion coefficient of ca. 30% of that of water. At the same time, water diffusion slows down as the DMMP concentration increases. This observation suggests that although sPS is permeable for both solvents, water and DMMP are partially segregated on the scale of 1-2 nm and have different pathways through the system. The nonuniform nanoscale distribution of water and DMMP in sPS is confirmed by analyses of different pair correlation functions. This feature may significantly affect the perm-selective properties of sPS-contained block copolymer membranes.

  9. Mechanisms for selective toxicity of fipronil insecticide and its sulfone metabolite and desulfinyl photoproduct.

    Science.gov (United States)

    Hainzl, D; Cole, L M; Casida, J E

    1998-12-01

    Fipronil, an N-phenylpyrazole with a trifluoromethylsulfinyl substituent, initiated the second generation of insecticides acting at the gamma-aminobutyric acid (GABA) receptor to block the chloride channel. The first generation includes the polychlorocycloalkanes alpha-endosulfan and lindane. In this study, we examine the mechanisms for selective toxicity of the sulfoxide fipronil and its sulfone metabolite and desulfinyl photoproduct relative to their target site interactions in vitro and ex vivo and the importance in fipronil action of biooxidation to the sulfone. Differences in GABA receptor sensitivity, assayed by displacement of 4'-ethynyl-4-n-[2, 3-3H2]propylbicycloorthobenzoate ([3H]EBOB) from the noncompetitive blocker site, appear to be a major factor in fipronil being much more toxic to the insects (housefly and fruit fly) than to the vertebrates (humans, dogs, mice, chickens, quail, and salmon) examined; in insects, the IC50s range from 3 to 12 nM for fipronil and its sulfone and desulfinyl derivatives, while in vertebrates, the IC50 average values are 1103, 175, and 129 nM for fipronil, fipronil sulfone, and desulfinyl fipronil, respectively. The insect relative to the vertebrate specificity decreases in the following order: fipronil > lindane > desulfinyl fipronil > fipronil sulfone > alpha-endosulfan. Ex vivo inhibition of [3H]EBOB binding in mouse brain is similar for fipronil and its sulfone and desulfinyl derivatives at the LD50 dose, but surprisingly, at higher doses fipronil can be lethal without detectably blocking the [3H]EBOB site. The P450 inhibitor piperonyl butoxide, acting in houseflies, increases the metabolic stability and effectiveness of fipronil and the sulfone but not those of the desulfinyl compound, and in mice it completely blocks the sulfoxide to sulfone conversion without altering the poisoning. Thus, the selective toxicity of fipronil and fipronil-derived residues is due in part to the higher potency of the parent compound at

  10. Neurotoxicity of perfluorooctane sulfonate to hippocampal cells in adult mice.

    Directory of Open Access Journals (Sweden)

    Yan Long

    Full Text Available Perfluorooctane sulfonate (PFOS is a ubiquitous pollutant and found in the environment and in biota. The neurotoxicity of PFOS has received much concern among its various toxic effects when given during developing period of brain. However, little is known about the neurotoxic effects and potential mechanisms of PFOS in the mature brain. Our study demonstrated the neurotoxicity and the potential mechanisms of PFOS in the hippocampus of adult mice for the first time. The impairments of spatial learning and memory were observed by water maze studies after exposure to PFOS for three months. Significant apoptosis was found in hippocampal cells after PFOS exposure, accompanied with a increase of glutamate in the hippocampus and decreases of dopamine (DA and 3,4-dihydrophenylacetic acid (DOPAC in Caudate Putamen in the 10.75 mg/kg PFOS group. By two-dimensional fluorescence difference in gel electrophoresis (2D-DIGE analysis, seven related proteins in the hippocampus that responded to PFOS exposure were identified, among which, Mib1 protein (an E3 ubiquitin-protein ligase, Herc5 (hect domain and RLD 5 isoform 2 and Tyro3 (TYRO3 protein tyrosine kinase 3 were found down-regulated, while Sdha (Succinate dehydrogenase flavoprotein subunit, Gzma (Isoform HF1 of Granzyme A precursor, Plau (Urokinase-type plasminogen activator precursor and Lig4 (DNA ligase 4 were found up-regulated in the 10.75 mg/kg PFOS-treated group compare with control group. Furthermore, we also found that (i increased expression of caspase-3 protein and decreased expression of Bcl-2, Bcl-XL and survivin proteins, (ii the increased glutamate release in the hippocampus. All these might contribute to the dysfunction of hippocampus which finally account for the impairments of spatial learning and memory in adult mice.

  11. Highly Sulfonated Diamine Synthesized Polyimides and Protic Ionic Liquid Composite Membranes Improve PEM Conductivity

    Directory of Open Access Journals (Sweden)

    Bor-Kuan Chen

    2015-06-01

    Full Text Available A novel sulfonated diamine was synthesized from 1,4-bis(4-aminophenoxy benzene [pBAB]. Sulfonated polyimides (SPIs were synthesized from sulfonated pBAB, 1,4-bis(4-aminophenoxy-2-sulfonic acid benzenesulfonic acid [pBABTS], various diamines and aromatic dianhydrides. Composite proton exchange membranes (PEMs made of novel SPIs and a protic ionic liquid (PIL 1-vinyl-3-H-imidazolium trifluoromethanesulfonate [VIm][OTf] showed substantially increased conductivity. We prepared an SPI/PIL composite PEM using pBABTS, 4,4′-(9-fluorenylidene dianiline (9FDA as diamine, 3,3′,4,4′-diphenylsulfone tetracarboxylic dianhydride (DSDA as dianhydride and 40 wt % [VIm][OTf] with a high conductivity of 16 mS/cm at 120 °C and anhydrous condition. pBABTS offered better conductivity, since the chemical structure had more sulfonated groups that provide increased conductivity. The new composite membrane could be a promising anhydrous or low-humidity PEM for intermediate or high-temperature fuel cells.

  12. Preparation of Sulfonated PVA-TMSP Membranes for Direct Methanol Fuel Cell

    Directory of Open Access Journals (Sweden)

    Haryadi

    2012-08-01

    Full Text Available Novel preparation and characterization of sulfonated polyvinyl alcohol (PVA–trimethoxysilyl propanethiol (TMSP membranes for direct methanol fuel cell (DMFC application have been investigated. Preparation of sulfonated PVA-TMSP membrane was conducted by crosslinking steps using sol-gel method and a catalyst of concentrated HCl. TMSP concentrations were varied from 1% to 3%. The gel solution was cast on to the membrane metal plate to obtain membrane sheets. The membrane was then oxidized in H2O2 concentrations of (10-30% to convert the mercapto groups into sulfonate group. Investigations of the cross-linking process and the existence of sulfonate group were conducted by infrared spectroscopy as shown for frequencies at 1140–1200/cm and 1200–1145/cm respectively. The scanning electron microscope–energy dispersive X-rays (SEM–EDX of the membranes indicated that the distribution of silica particles from sol–gel reaction products was uneven due to the fast exchange rate of condensation. The degree of swelling decreased as methanol concentrations increase for sulfonated PVA–TMSP membrane which opposed toward the value of commercial Nafion membrane. The maximum value of ion exchange capacity of the membrane was 1.82 mmol/g whereas the highest proton conductivity was 3.9 x 10-4 S/cm. Therefore it can be concluded that the membrane was a potential candidate for application in DMFC.

  13. The host cell sulfonation pathway contributes to retroviral infection at a step coincident with provirus establishment.

    Directory of Open Access Journals (Sweden)

    James W Bruce

    2008-11-01

    Full Text Available The early steps of retrovirus replication leading up to provirus establishment are highly dependent on cellular processes and represent a time when the virus is particularly vulnerable to antivirals and host defense mechanisms. However, the roles played by cellular factors are only partially understood. To identify cellular processes that participate in these critical steps, we employed a high volume screening of insertionally mutagenized somatic cells using a murine leukemia virus (MLV vector. This approach identified a role for 3'-phosphoadenosine 5'-phosphosulfate synthase 1 (PAPSS1, one of two enzymes that synthesize PAPS, the high energy sulfate donor used in all sulfonation reactions catalyzed by cellular sulfotransferases. The role of the cellular sulfonation pathway was confirmed using chemical inhibitors of PAPS synthases and cellular sulfotransferases. The requirement for sulfonation was mapped to a stage during or shortly after MLV provirus establishment and influenced subsequent gene expression from the viral long terminal repeat (LTR promoter. Infection of cells by an HIV vector was also shown to be highly dependent on the cellular sulfonation pathway. These studies have uncovered a heretofore unknown regulatory step of retroviral replication, have defined a new biological function for sulfonation in nuclear gene expression, and provide a potentially valuable new target for HIV/AIDS therapy.

  14. One Step Preparation of Sulfonated Solid Catalyst and Its Effect in Esterification Reaction

    Institute of Scientific and Technical Information of China (English)

    康世民; 常杰; 范娟

    2014-01-01

    A carbon-based sulfonated catalyst was prepared by direct sulfonation and carbonization (in moderate conditions:200 °C, 12 h) of red liquor solids, a by-product of paper-making process. The prepared sulfonated cata-lyst (SC) had aromatic structure, composed of carbon enriched inner core, and oxygen-containing (SO3H, COOH, OH) groups enriched surface. The SO3H, COOH, OH groups amounted to 0.74 mmol·g-1, 0.78 mmol·g-1, 2.18 mmol·g-1, respectively. The fresh SC showed much higher catalytic activity than that of the traditional solid acid catalysts (strong-acid 732 cation exchange resin, hydrogen type zeolite socony mobile-five (HZSM-5), sulfated zir-conia) in esterification of oleic acid. SC was deactivated during the reactions, through the mechanisms of leaching of sulfonated species and formation of sulfonate esters. Two regeneration methods were developed, and the catalytic activity can be mostly regenerated by regeneration Method 1 and be fully regenerated by regeneration Method 2, respectively.

  15. EFFECT OF SOLVENT COMPOSITION ON THE SULFONATION DEGREE OF OLY(PHENYLENE OXIDE) (PPO)

    Institute of Scientific and Technical Information of China (English)

    Tong-wen Xu; Wei-hua Yang; Bing-lin He

    2002-01-01

    This paper investigates the possibility of attaining sulphonated poly(phenylene oxide) (SPPO) with a relatively higher sulfonation degree. To achieve this aim, the approach we adopt is to improve the solubility of the final product in the mixed solvent so that the sulfonation may take place between the bulk solutions and PPO powders even at higher sulfonation degree. It is shown that the addition of a proper amount of dimethyl formide (DMF) to the conventional PPO-chloroform system can actually enhance the sulfonation effect. The solvent composition is then correlated with the sulfonation degree based on the solubility parameters. It is interesting to find that solubility parameters between the mixed solvent and the precipitated products keep an approximately unchanged value at about 4.9, which is just equal to that when pure chloroform is used, though the solubility parameters of both solvents increase with the content of DMF in solution. This may be the main reason why the addition of DMF can reduce the precipitation and improve the ion exchange capacity (IEC) of SPPO polymer.

  16. Polymer electrolyte membranes from fluorinated polyisoprene-block-sulfonated polystyrene: Membrane structure and transport properties

    Energy Technology Data Exchange (ETDEWEB)

    Sodeye, Akinbode [Department of Polymer Science and Engineering, University of Massachusetts; Huang, Tianzi [University of Tennessee, Knoxville (UTK); Gido, Samuel [University of Massachusetts, Amherst; Mays, Jimmy [ORNL

    2011-01-01

    With a view to optimizing morphology and ultimately properties, membranes have been cast from relatively inexpensive block copolymer ionomers of fluorinated polyisoprene-block-sulfonated polystyrene (FISS) with various sulfonation levels, in both the acid form and the cesium neutralized form. The morphology of these membranes was characterized by transmission electron microscopy and ultra-small angle X-ray scattering, as well as water uptake, proton conductivity and methanol permeability within the temperature range from 20 to 60 C. Random phase separated morphologies were obtained for all samples except the cesium sample with 50 mol% sulfonation. The transport properties increased with increasing degree of sulfonation and temperature for all samples. The acid form samples absorbed more water than the cesium samples with a maximum swelling of 595% recorded at 60 C for the acid sample having 50 mol% sulfonation. Methanol permeability for the latter sample was more than an order of magnitude less than for Nafion 112 but so was the proton conductivity within the plane of the membrane at 20 C. Across the plane of the membrane this sample had half the conductivity of Nafion 112 at 60 C.

  17. CHARACTERIZATION OF SULFONATED SYNDIOTACTIC POLYSTYRENE%磺化间规聚苯乙烯的表征

    Institute of Scientific and Technical Information of China (English)

    王进; 祝方明; 刘金成; 黎华明; 林尚安

    2001-01-01

    The effect of different sulfonation degree on properties of sulfonated syndiotactic polystyrene(SsPS) was investigated by 1H-NMR,13C-NMR,FTIR,DSC and WAXD.The results of 13C-NMR showed that a peak at δ=145.5 appeared in all SsPS spectra,which proved that the syndiotactic structure of syndiotactic polystyrene(sPS) still existed in SsPS.With increasing degree of sulfonition,the chemical shifts of C-1 and C\\|3 for sulfonated benzene ring turned out to be wider.1H-NMR spectra showed that C\\|3 for sulfonated benzene ring had a chemical shift of 7.66.FTIR spectra showed that sulfonic acid groups were introduced on the para position of benzene rings and with increasing sulfonation degree,the absorption strength of 612/1600 cm-1,834/1600cm-1 increased,but the absorption strength of 1078/1600cm-1 decreased.The absorption of ~1030cm-1,~1179cm-1,~1217cm-1 appeared when the sulfonation degree was higher that 6%.sPS and SsPS-H-2.2 had absorption at 975 and 943cm-1 and also had double peaks around ~1175cm-1;DSC showed that with increasing sulfonation degree, the glass transition temperature increased, the melt temperature,crystallization temperature and crystallization degree decreased;SsPS couldn't crystallize when sulfonation degree was higher that 6mol%;WAXD proved that sPS had the α and β crystal types, however,SsPS with 2.2% sulfonation degree only had the β crystal type, and SsPS with 6.1% sulfonation degree didn't crystallize.

  18. Las bases celulares de las oscilaciones neuronales

    OpenAIRE

    Mario Treviño; Rafael Gutiérrez

    2007-01-01

    Una de las características de los circuitos neuronales es que sus componentes, las neuronas, pueden presentar actividad eléctrica sincrónica y, gracias a ésta, generar actividad oscilatoria. Esta actividad se ha asociado a diversas funciones fisiológicas como el procesamiento de información sensorial, la memoria, el ciclo vigiliasueño y la conciencia. La actividad oscilatoria de un circuito neuronal está mediada por i) las propiedades intrínsecas de sus células, ii) la arquitectura de sus con...

  19. Interaction of linear alkylbenzol soda-sulphonate (LAS) with heavy metals; Interaccion del alquilbenceno sulfonato sodico lineal (LAS) con los metales pesados

    Energy Technology Data Exchange (ETDEWEB)

    Verge, C.; Bengoechea, C.; Bravo, J.; Lopez, L.; Moreno, A. [Petroquimica Espanola, S. a. Cadiz (Spain)

    2000-07-01

    Precipitation boundary diagrams of LAS (Linear Alkyl Benzene Sulfonate) homologues {phi}C-{sub 1}1, {phi}C{sub 1}2, {phi}C{sub 1}3, Vs. heavy metals Cu, Pb, and Zn, have been studied. The precipitation boundary is the graphical representation of points at which the onset of precipitation is observed. The diagrams is divided in areas where only monomers or micelles or both exist. The bioavailability of precipitated LAS-heavy metal systems is considered to be much lower than the corresponding ions when they are in solution. As a consequence of that, the acute toxicity of these systems is highly dependent on the environmental conditions. Additional influencing factors, such as ionic strength, pH, and organic matter present, make very difficult to establish on a quantitative basis the risk assessment of this LAS-heavy metal complex. (Author) 18 refs.

  20. Mechanoassisted Synthesis of Sulfonated Covalent Organic Frameworks with High Intrinsic Proton Conductivity.

    Science.gov (United States)

    Peng, Yongwu; Xu, Guodong; Hu, Zhigang; Cheng, Youdong; Chi, Chenglong; Yuan, Daqiang; Cheng, Hansong; Zhao, Dan

    2016-07-20

    It is challenging to introduce pendent sulfonic acid groups into modularly built crystalline porous frameworks for intrinsic proton conduction. Herein, we report the mechanoassisted synthesis of two sulfonated covalent organic frameworks (COFs) possessing one-dimensional nanoporous channels decorated with pendent sulfonic acid groups. These COFs exhibit high intrinsic proton conductivity as high as 3.96 × 10(-2) S cm(-1) with long-term stability at ambient temperature and 97% relative humidity (RH). In addition, they were blended with nonconductive polyvinylidene fluoride (PVDF) affording a series of mixed-matrix membranes (MMMs) with proton conductivity up to 1.58 × 10(-2) S cm(-1) and low activation energy of 0.21 eV suggesting the Grotthuss mechanism for proton conduction. Our study has demonstrated the high intrinsic proton conductivity of COFs shedding lights on their wide applications in proton exchange membranes.

  1. Influence of charge densities of randomly sulfonated polystyrene surfaces on cell attachment and proliferation.

    Science.gov (United States)

    Khatua, Dibyendu; Kwak, Byeongdo; Shin, Kwanwoo; Song, Ju-Myung; Kim, Joon-Seop; Choi, Jai-Hak

    2011-05-01

    Attachment and proliferation of NIH-3T3 fibroblast cells on random polymer surfaces, polystyrene sulfonated acid (PSSAx) with five different degrees of sulfonation (x = 0%, 5%, 10%, 15% and 33%) and on a tissue culture polystyrene (TCPS) surface were studied. The surface properties, wettability and roughness were measured by water-contact angle and atomic force microscopy measurement. The wettability and surface roughness increased with increasing the content of sulfonic acid groups on the surfaces. The number of cells attached on the surface after seeding increased with increasing x and reached to the maximum value on PSSA15. The cell proliferation also increased with increasing x. However, cell proliferation was slow down on PSSA33 in comparison to PSSA10 and PSSA15 surfaces after 48 h culture.

  2. Structure-Properties Relationship in Proton Conductive Sulfonated Polystyrene-Polymethyl Methacrylate Block Copolymers.

    Science.gov (United States)

    Rubatat, Laurent; Li, Chaoxu; Dietsch, Herve; Nykainen, Antti; Ruokolainen, Janne; Mezzenga, Raffaele

    2009-03-01

    We report on the dependence of proton conductivity on the morphologies of sulfonated polystyrene-poly(methyl methacrylate) (sPS-PMMA) diblock copolymers. Three diblock copolymers of varying molecular weight and block volume fraction were studied, for each one several sulfonation degrees of the PS block were considered. The investigation of the morphologies of the self-assembled sPS-PMMA diblocks was carried out by means of small angle neutron scattering and transmission electron microscopy. Depending on molecular weight and sulfonation degrees, isotropic phase (ISO), lamellar phase (LAM), cylindrical hexagonal phase (HEX) and hexagonally perforated lamellae (HPL) were observed. Proton conductivity, normalized by the volume fraction of the conductive domains (formed by PS, sPS and water), was shown to rise monotonically with the following sequence of morphologies: ISO to HEX to HPL to LAM.

  3. Sulfonated dyes attenuate the toxic effects of beta-amyloid in a structure-specific fashion.

    Science.gov (United States)

    Pollack, S J; Sadler, I I; Hawtin, S R; Tailor, V J; Shearman, M S

    1995-09-15

    We recently reported that several sulfate-containing glycosaminoglycans, a class of compounds associated with the beta-amyloid plaques of Alzheimer's disease, attenuate the toxic effects of beta-amyloid fragments beta 25-35 and beta 1-40. The amyloid-binding sulfonated dye Congo Red was shown to have a similar effect. Using two clonal cell lines, we now demonstrate that several sulfonated dyes attenuate beta-amyloid toxicity and that the protective effect appears specific for compounds whose sulfonate groups can interact with the beta-pleated structure of aggregated amyloid. These results suggest that by binding beta-amyloid these compounds may prevent toxic interactions of the peptide with cells.

  4. Synthesis of porous sulfonated carbon as a potential adsorbent for phenol wastewater.

    Science.gov (United States)

    Prabhu, Azhagapillai; Al Shoaibi, Ahmed; Srinivasakannan, C

    2015-01-01

    The work reports a facile synthesis procedure for preparation of porous sulfonated carbons and its suitability for adsorption of phenol. The sulfonated carbon was synthesized utilizing a simplified, single-step, shorter duration process by sulfonation, dehydration and carbonization of sucrose in sulfuric acid and tetraethylorthosilicate. The surface and internal structures of the adsorbents were characterized utilizing various characterization techniques to understand the porous nature and surface functional groups of the porous matrix. Adsorption capacity was found to be highest for the sample heat treated at 600 °C, with the maximum adsorption capacity of 440 mg/g at 30 °C. The adsorption isotherms were tested with the Freundlich and Langmuir adsorption isotherms models to identify the appropriate adsorption mechanism.

  5. Nuclear Magnetic Resonance Identification of New Sulfonic Acid Metabolites of Chloroacetanilide Herbicides

    Science.gov (United States)

    Morton, M.D.; Walters, F.H.; Aga, D.S.; Thurman, E.M.; Larive, C.K.

    1997-01-01

    The detection of the sulfonic acid metabolites of the chloroacetanilide herbicides acetochlor, alachlor, butachlor, propachlor, and, more recently, metolachlor in surface and ground water suggests that a common mechanism for dechlorination exists via the glutathione conjugation pathway. The identification of these herbicides and their metabolites is important due to growing public awareness and concern about pesticide levels in drinking water. Although these herbicides are regulated, little is known about the fate of their metabolites in soil. The sulfonic acid metabolites were synthesized by reaction of the parent compounds with an excess of sodium sulfite. Acetochlor, alachlor, butachlor, metolachlor, and propachlor and their sulfonic acid metabolites were studied by nuclear magnetic resonance spectroscopy and fast atom bombardment mass spectrometry. This paper provides a direct method for the preparation and characterization of these compounds that will be useful in the analysis and study of chloracetanilide herbicides and their metabolites.

  6. Synthesis and Process Optimization of Electrospun PEEK-Sulfonated Nanofibers by Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Carlo Boaretti

    2015-07-01

    Full Text Available In this study electrospun nanofibers of partially sulfonated polyether ether ketone have been produced as a preliminary step for a possible development of composite proton exchange membranes for fuel cells. Response surface methodology has been employed for the modelling and optimization of the electrospinning process, using a Box-Behnken design. The investigation, based on a second order polynomial model, has been focused on the analysis of the effect of both process (voltage, tip-to-collector distance, flow rate and material (sulfonation degree variables on the mean fiber diameter. The final model has been verified by a series of statistical tests on the residuals and validated by a comparison procedure of samples at different sulfonation degrees, realized according to optimized conditions, for the production of homogeneous thin nanofibers.

  7. Polymer electrolyte membranes from fluorinated polyisoprene-block-sulfonated polystyrene: Structural evolution with hydration and heating

    Energy Technology Data Exchange (ETDEWEB)

    Sodeye, Akinbode [Department of Polymer Science and Engineering, University of Massachusetts; Huang, Tianzi [University of Tennessee, Knoxville (UTK); Gido, Samuel [University of Massachusetts, Amherst; Mays, Jimmy [ORNL

    2011-01-01

    Small-angle neutron scattering (SANS) and ultra-small-angle X-ray scattering (USAXS) have been used to study the structural changes in fluorinated polyisoprene/sulfonated polystyrene (FISS) diblock copolymers as they evolved from the dry state to the water swollen state. A dilation of the nanometer-scale hydrophilic domains has been observed as hydration increased, with greater dilation occurring in the more highly sulfonated samples or upon hydration at higher temperatures. Furthermore, a decrease in the order in these phase separated structures is observed upon swelling. The glass transition temperatures of the fluorinated blocks have been observed to decrease upon hydration of these materials, and at the highest hydration levels, differential scanning calorimetry (DSC) has shown the presence of tightly bound water. A precipitous drop in the mechanical integrity of the 50% sulfonated materials is also observed upon exceeding the glass transition temperature (Tg), as measured by dynamic mechanical analysis (DMA).

  8. Las versiones homericas Las versiones homericas

    Directory of Open Access Journals (Sweden)

    Jorge Luis Borges

    2008-04-01

    Full Text Available Ningún problema tan consustancial con las letras con su modesto misterio como el que propone una traducción. Un olvido animal por la vanidad, el tenor de confesar procesos mentales que adivinamos peligrosamente comunes, el conato de mantener intacta y central una reserve incalculable de sombre, velan las tales escrituras directas. La traducciOn, en cambio, parece destinada a ilustrar la discusión estitica. El modelo propuesto a su imitaciOn es un texto visible, no un labirint° inestimable de proyectos preteritos o la acatada tentaciOn momentanea de una facilidad. Bertrand Russell define un objeto extern( como un sistema circular, irradiante, de impresiones posibles; lo mismo puede aseverarse de un texto, dadas las repercusiones incalculables de lo verbal. Un parcial y precioso documento de las vicisitudes que sufre queda en sus traducciones.

  9. Formation of core (polystyrene)-shell (polybenzimidazole) nanoparticles using sulfonated polystyrene as template.

    Science.gov (United States)

    Hazarika, Mousumi; Arunbabu, Dhamodaran; Jana, Tushar

    2010-11-15

    We report formation of core (polystyrene)-shell (polybenzimidazole) nanoparticles from a new blend system consisting of an amorphous polymer polybenzimidazole (PBI) and an ionomer sodium salt of sulfonated polystyrene (SPS-Na). The ionomer used for the blending is spherical in shape with sulfonate groups on the surface of the particles. An in depth investigation of the blends at various sulfonation degrees and compositions using Fourier transform infrared (FT-IR) spectroscopy provides direct evidence of specific hydrogen bonding interactions between the N-H groups of PBI and the sulfonate groups of SPS-Na. The disruption of PBI chains self association owing to the interaction between the functional groups of these polymer pairs is the driving force for the blending. Thermodynamical studies carried out by using differential scanning calorimeter (DSC) establish partially miscible phase separated blending of these polymers in a wider composition range. The two distinguishable glass transition temperatures (T(g)) which are different from the neat components and unaltered with the blends composition attribute that the domain size of heterogeneity (d(d)) of the blends is >20 nm since one of the blend component (SPS-Na particle) diameter is ∼70 nm. The diminish of PBI chains self association upon blending with SPS-Na particles and the presence of invariant T(g)'s of the blends suggest the wrapping of PBI chains over the SPS-Na spherical particle surface and hence resulting a core-shell morphology. Transmission electron microscopy (TEM) study provides direct evidence of core-shell nanoparticle formation; where core is the polystyrene and shell is the PBI. The sulfonation degree affects the blends phase separations. The higher degree of sulfonation favors the disruption of PBI self association and thus forms partially miscible two phases blends with core-shell morphology.

  10. Las lenguas en las sociedades del conocimiento

    Directory of Open Access Journals (Sweden)

    Álvarez, J. Francisco

    2008-12-01

    Full Text Available Languages become a strategic resource for information and knowledge societies. By expressing and sharing knowledge by means of languages, every culture generates deposits of knowledge, which can be transferred and exchanged among different epistemic communities. The contemporary technologies of information and communication have changed the structure of knowledge flows. Globalization of knowledge poses a great challenge to every language, including the Spanish one. In order to survive in the digital world, they should develop technolanguages. The lemma “Thinking in Spanish” implies a new model of governance for the Ibero-American knowledge communities.En las sociedades de la información y el conocimiento las lenguas se convierten en un recurso estratégico. Al expresar y compartir conocimiento por medio de los idiomas, las culturas generan yacimientos de conocimiento, que pueden ser transferidos e intercambiados entre comunidades epistémicas diferentes. Las actuales tecnologías de la información y la comunicación han cambiado la estructura de los flujos de conocimiento. La globalización del conocimiento plantea un gran desafío a todas las lenguas, incluyendo la española. Para sobrevivir en el mundo digital, los lenguajes han de convertirse en tecnolenguajes. El lema “Pensar en español” aporta un nuevo modelo de gobernanza para las comunidades iberoamericanas del conocimiento.

  11. [Calcium polystyrene sulfonate induced colonic necrosis in patient with chronic kidney disease].

    Science.gov (United States)

    Lee, Sung Hoa; Kim, Sung Jung; Kim, Go Eun; Lee, Woo Jin; Hong, Won Ki; Baik, Gwang Ho; Choi, Young Hee; Kim, Dong Joon

    2010-04-01

    A 63-year-old woman was admitted due to right upper quadrant abdominal pain. She was going through hemodialysis due to end stage renal disease and taking calcium polystyrene sulfonate orally and rectally due to hyperkalemia. Colonoscopy showed a circular ulcerative mass on the proximal ascending colon. Biopsy specimen from the mass showed inflammation and necrotic debris. It also revealed basophilic angulated crystals which were adherent to the ulcer bed and normal mucosa. These crystals were morphologically consistent with calcium polystyrene sulfonate. She was diagnosed with calcium polystyrene phosphate induced colonic necrosis and improved with conservative treatment.

  12. Colonic necrosis and perforation due to calcium polystyrene sulfonate in a uraemic patient: a case report.

    Science.gov (United States)

    Akagun, Tulin; Yazici, Halil; Gulluoglu, Mine G; Yegen, Gulcin; Turkmen, Aydin

    2011-12-01

    Sodium or calcium polystyrene sulfonate (Kayexalate or analog) is an ion-exchange resin commonly used to treat hyperkalaemia in patients with chronic kidney disease. It is known to cause digestive complications, such as nausea, vomiting and constipation. Although rare, colonic necrosis and perforation are very severe complications associated with the medication. In this case report, we present a case of calcium polystyrene sulfonate-induced colonic necrosis and perforation to remind clinicians of this rare, but dangerous, toxicity associated with this commonly used medication.

  13. Cloning and Characterization of a Sulfonate/α-Ketoglutarate Dioxygenase from Saccharomyces cerevisiae

    OpenAIRE

    Hogan, Deborah A; Auchtung, Thomas A.; Hausinger, Robert P.

    1999-01-01

    The Saccharomyces cerevisiae open reading frame YLL057c is predicted to encode a gene product with 31.5% amino acid sequence identity to Escherichia coli taurine/α-ketoglutarate dioxygenase and 27% identity to Ralstonia eutropha TfdA, a herbicide-degrading enzyme. Purified recombinant yeast protein is shown to be an Fe(II)-dependent sulfonate/α-ketoglutarate dioxygenase. Although taurine is a poor substrate, a variety of other sulfonates are utilized, with the best natural substrates being is...

  14. Pearlnecklacelike chain conformation of hydrophobic polyelectrolyte: a SANS study of partially sulfonated polystyrene in water.

    OpenAIRE

    Boué, François; Noelle Spiteri, Marie; Williams, Claudine

    2007-01-01

    International audience; The form factor of partially sulfonated polystyrene PSSNa (degree of sulfonation f =1, 0.72, 0.64 and 0.36), at polymer concentration 0.17M and 0.34M, without or with added salt (0 M, 0.34M, & 0.68M), is measured by Small Angle Neutron Scattering using the Zero Average Contrast method. The total scattering function is also measured, allowing extracting the distinct interchain function and an apparent structure factor. The main result is the behavior of the form factor ...

  15. Microwave Assisted Hydrolysis of Holocellulose Catalyzed with Sulfonated Char Derived from Lignin-Rich Residue

    Directory of Open Access Journals (Sweden)

    Kui Wang

    2015-01-01

    Full Text Available A microwave assisted green process has been developed for production of sugars through liquefying holocellulose catalyzed with sulfonated char derived from the lignin-rich residue produced during pretreatment of lignocellulose. Various reaction parameters including the hydrolysis temperature, hydrolysis time, catalyst content, and the ratio of water to feedstock were evaluated. The maximum sugars yield of 82.6% (based on the dry mass of holocellulose was obtained under the optimum reaction conditions. The sulfonated char showed superior catalytic performance to that of dilute sulfuric acid in converting holocellulose into sugars under microwave irradiation.

  16. Preparation and Reactions of Amino Acid Ester Sulfones as New Remote Asymmetrical Induced Reagents

    Institute of Scientific and Technical Information of China (English)

    ZHOU,Cheng-He; BAI,Xue; LI,Tan-Qing; WU,Jun; Alfred Hassner

    2004-01-01

    @@ The development of chiral auxiliary-controlled asymmetric synthesis has been receiving increasing interest in recent yearsfi,2] Various chiral auxiliary reagents have been observed[3] and a lot of results showed that variation of the chiral auxiliary could influence asymmetric induction. Recently, it has been reported the reaction of the aminated sulfones as a remote chiral auxiliary with α,β-unsaturated carbonyl compounds.[4] Here we would like to report the preparation of amino acid ester sulfones as new remote asymmetrical induced reagents and their reactions with α,β-unsaturated esters.

  17. Sulfonated copolyimide membranes derived from a novel diamine monomer with pendant benzimidazole groups for fuel cells

    DEFF Research Database (Denmark)

    Li, Wei; Guo, Xiaoxia; Aili, David;

    2015-01-01

    . A series of sulfonated copolyimides (SPI) are prepared via random copolymerizatio of 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA) with a new diamine monomer with pendant benzimidazole groups, 2,2'-bis(4-(1H-benzo[d]imidazol-2-yl)phenoxy)benzidine (BIPOB), and a sulfonated diamine monomer 4,4'-bis...... pendant groups significantly improves the hydrolytic stability as well as the radical oxidative stability of the membranes. In addition, the SPI membranes exhibit high proton conductivities of 0.1 S cm(-1) in the fully hydrated state at 60 degrees C and high elastic modulus and tensile strength...

  18. Synthesis and characterization of polystyrene-poly(arylene ether sulfone)-polystyrene triblock copolymer for proton exchange membrane applications.

    Science.gov (United States)

    Yang, Jung-Eun; Hong, Young Talk; Lee, Jae-Suk

    2006-11-01

    The polystyrene-poly(arylene ether sulfone)-polystyrene (PS-PAES-PS) coil-semirod-coil triblock copolymer was synthesized by the condensation reaction of PS-COCI and H2N-PAES-NH2 telechelic polymers. The reaction was facile characterized by high yields with a perfect control over the block lengths. Following a known reaction protocol it was possible to selectively sulfonate the PS block of the triblock copolymer that led to the sulfonated copolymer sPS-PAES-sPS. Studies on its proton conductivity and methanol permeability were carried out to evaluate its use as the proton exchange membrane in direct methanol fuel cells. Proton conductivity of the membranes was increased depending on the sulfonic acid group content in the sulfonated polymer. The membranes exhibited good dimensional and thermal stability, and low methanol permeability compared to Nafion 117.

  19. Data requirements of GREAT-ER: Modelling and validation using LAS in four UK catchments

    Energy Technology Data Exchange (ETDEWEB)

    Price, Oliver R., E-mail: oliver.price@unilever.co [Safety and Environmental Assurance Centre, Unilever, Colworth Science Park, Sharnbrook, Bedfordshire MK44 1LQ (United Kingdom); Munday, Dawn K. [Safety and Environmental Assurance Centre, Unilever, Colworth Science Park, Sharnbrook, Bedfordshire MK44 1LQ (United Kingdom); Whelan, Mick J. [Department of Natural Resources, School of Applied Sciences, Cranfield University, College Road, Cranfield, Bedfordshire MK43 0AL (United Kingdom); Holt, Martin S. [ECETOC, Ave van Nieuwenhuyse 4, Box 6, B-1160 Brussels (Belgium); Fox, Katharine K. [85 Park Road West, Birkenhead, Merseyside CH43 8SQ (United Kingdom); Morris, Gerard [Environment Agency, Phoenix House, Global Avenue, Leeds LS11 8PG (United Kingdom); Young, Andrew R. [Wallingford HydroSolutions Ltd, Maclean building, Crowmarsh Gifford, Wallingford, Oxon OX10 8BB (United Kingdom)

    2009-10-15

    Higher-tier environmental risk assessments on 'down-the-drain' chemicals in river networks can be conducted using models such as GREAT-ER (Geography-referenced Regional Exposure Assessment Tool for European Rivers). It is important these models are evaluated and their sensitivities to input variables understood. This study had two primary objectives: evaluate GREAT-ER model performance, comparing simulated modelled predictions for LAS (linear alkylbenzene sulphonate) with measured concentrations, for four rivers in the UK, and investigate model sensitivity to input variables. We demonstrate that the GREAT-ER model is very sensitive to variability in river discharges. However it is insensitive to the form of distributions used to describe chemical usage and removal rate in sewage treatment plants (STPs). It is concluded that more effort should be directed towards improving empirical estimates of effluent load and reducing uncertainty associated with usage and removal rates in STPs. Simulations could be improved by incorporating the effect of river depth on dissipation rates. - Validation of GREAT-ER.

  20. Las especies invasoras vertebradas

    OpenAIRE

    Monge Meza, Javier

    2016-01-01

    Se presenta la definición de especie invasora, así como diversos enfoques relacionados con la temática. Se indican las etapas del proceso de invasión biológica y las limitaciones para que muchas de las especies lo concreten, así como la importancia de la participación humana. Se hace referencia a los impactos de las especies vertebradas invasoras y las supuestas repercusiones para la biodiversidad, así como a las opiniones divergentes en cuanto a su verdadero efecto, en virtud de los datos qu...

  1. Las incubadoras de las empresas de Quebec

    Directory of Open Access Journals (Sweden)

    Bernardo Parra Restrepo

    1993-01-01

    Full Text Available Este articulo contiene información de las incubadoras de empresas especialmente aquellas encontradas en Quebec. A través de los 80's, el concepto de incubadoras de empresas fue introducido en América por expertos en el desarrollo económico. Sus metas fueron el estudio de los efectos del desempleo resultante de la quiebra de plantas industriales o del uso del proceso de producción automático por parte de las grandes compañías. Además se esperaba crear empleo para los inmigrantes. El campo más prometedor de estas experiencias se encuentra en el desarrollo de alta tecnología industrial, especialmente en electrónica, microprocesadores y software para sistemas de computación. Esta área también cubre las industrias innovadoras.

  2. las Comunicaciones (tics

    Directory of Open Access Journals (Sweden)

    Fernando Iriarte Díazgranados

    2007-01-01

    Full Text Available En este artículo se presenta un análisis de los resultados de estudios sobre la penetración de las Tecnologías de la Información y las Comunicaciones (TICS en países como España y Colombia. El análisis se centra en las posibles consecuencias, tanto positivas como negativas, que estas tecnologías pueden tener en la vida de los niños, y en el papel que las familias pueden asumir para que su utilización sea lo más beneficiosa posible.

  3. Las fronteras del istmo

    OpenAIRE

    2013-01-01

    Obra organizada en torno a seis ejes principales que estudian la importancia de comparar las fronteras y los tipos de gestión desde el punto de vista geopolítico, histórico y antropológico; las tramas de la organización del espacio actual; la influencia en la evolución de las sociedades debido a la violencia política y los conflictos armados; los movimientos migratorios internacionales; la integración política y económica y finalmente los lazos comunitarios y de las identidades relacionados c...

  4. Las sentencias constitucionales exhortativas

    Directory of Open Access Journals (Sweden)

    Néstor Pedro Sagües

    2006-01-01

    Full Text Available Como producto del derecho judicial, diferentes tribunales constitucionales europeos han desarrollado nuevos tipos de sentencias atípicas, diferentes de las tradicionales. Entre ellas, las “exhortativas” recomiendan al legislador (incluso al constituyente dictar nuevas normas en reemplazo de las actualmente en vigor, para que estén bajo la Constitución. En el caso argentino, recientemente la Corte Suprema las ha admitido en un hábeas corpus colectivo destinado a mejorar la situación de detenidos en cárceles de la Provincia de Buenos Aires.

  5. Las humanidades entre las cuerdas del neoliberalismo

    OpenAIRE

    Rodríguez Reyes, Abdiel

    2015-01-01

    Este  artículo problematiza la situación de las humanidades en el auge del neoliberalismo. Propone que para comprender el mundo moderno es necesario problematizar e interrelacionar los ámbitos del saber humanístico, científico y tecnológico. También crítica la visión que se tiene de la educación al servicio exclusivo de la sociedad de mercado y las élites financieras.

  6. DETERMINATION OF ALKYLATED & SULFONATED DIPHENYL OXIDE SULFACTANT BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

    Science.gov (United States)

    Methods for the determination of the anionic surfactant Dowfax 8390 are described. Dowfax is a complex mixture of various alkylated and sulfonated diphenyl oxides. The primary component of Dowfax is monoalkylated disulfonated diphenyl oxide (MADS). This work uses ion pairing chro...

  7. Optical anisotropy, molecular orientations, and internal stresses in thin sulfonated poly(ether ether ketone) films

    NARCIS (Netherlands)

    Koziara, B.T.; Nijmeijer, D.C.; Benes, N.E.

    2015-01-01

    The thickness, the refractive index, and the optical anisotropy of thin sulfonated poly(ether ether ketone) films, prepared by spin-coating or solvent deposition, have been investigated with spectroscopic ellipsometry. For not too high polymer concentrations (B5 wt%) and not too low spin speeds (C20

  8. Silver(Ⅰ)-mediated reaction of trimethylsilylated arylacetylenes with sulfonyl chlorides: Unexpected formation of vinyl sulfones

    Institute of Scientific and Technical Information of China (English)

    Gui Sheng Deng; Teng Fei Sun

    2012-01-01

    A novel reaction of trimethylsilylated arylacetylenes with sulfonyl chlorides was performed in the presence of silver nitrate or triflate.Conjugated vinyl sulfones as dramatic products were obtained in moderate yields and with Z-selectivity.A free radical mechanism has been proposed to account for the formation of the products.

  9. PLENARY LECTURES-PL1 Toxicity of perfluorooctane sulfonate and perfluorooctanoate

    Institute of Scientific and Technical Information of China (English)

    S TSUDA; I SATO; N SAITO; K OAMI; JIN YH4

    2006-01-01

    @@ Persistent perfluorinated organic compounds, such as perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are used in a variety of industrial applications. They are very stable in the environment, distribute widely in the global environment and in wild life, and are detected in human sera.

  10. Sulfonated carbon black-based composite membranes for fuel cell applications

    Indian Academy of Sciences (India)

    Hacer Doǧan; Emel Yildiz; Metin Kaya; Tülay Y Inan

    2013-08-01

    Two different commercial grade carbon black samples, Cabot Regal 400R (C1) and Cabot Mogul L (C2), were sulfonated with diazonium salt of sulfanilic acid. The resultant sulfonated carbon black samples (S–C) were characterized by Fourier transform infrared spectroscopy (FTIR) and thermal gravimetric analysis (TGA). Composite membranes were then prepared using S–C as fillers and sulfonated poly(ether ether ketone) (SPEEK) as polymer matrix with three different sulfonation degrees (DS = 60, 70 and 82%). Structure and properties of the composite membranes were characterized by FTIR, TGA, scanning electron microscopy, proton conduction, water uptake, ion exchange capacity and chemical stability. Incorporation of S–C particles above 0.25 wt% caused decrease in chemical stability. Pristine and composite membranes prepared from SPEEK82 decomposed completely in <1 h, which is undesirable for fuel cell applications. SPEEK60 membrane having wt% of 0.25–0.5 with S–C particles led to higher proton conductivity than that of pristine membrane. No positive effect was observed on the properties of the composite membranes with the addition of S–C particles at high concentrations due to the agglomeration problems and decrease in the content of conductive polymer matrix.

  11. Covalently Cross-Linked Sulfone Polybenzimidazole Membranes with Poly(Vinylbenzyl Chloride) for Fuel Cell Applications

    DEFF Research Database (Denmark)

    Yang, Jingshuai; Aili, David; Li, Qingfeng;

    2013-01-01

    Covalently cross-linked polymer membranes were fabricated from poly(aryl sulfone benzimidazole) (SO(2) PBI) and poly(vinylbenzyl chloride) (PVBCl) as electrolytes for high-temperature proton-exchange-membrane fuel cells. The cross-linking imparted organo insolubility and chemical stability against...

  12. Jacobsen protocols for large-scale epoxidation of cyclic dienyl sulfones: application to the (+)-pretazettine core.

    Science.gov (United States)

    Ebrahimian, G Reza; du Jourdin, Xavier Mollat; Fuchs, Philip L

    2012-05-18

    A Jacobsen epoxidation protocol using H2O2 as oxidant was designed for the large-scale preparation of various epoxy vinyl sulfones. A number of cocatalysts were screened, and pH control led to increased reaction rate, higher turnover number, and improved reliability.

  13. Albumin adsorption on unmodified and sulfonated polystyrene surfaces, in relation to cell-substratum adhesion.

    Science.gov (United States)

    Kowalczyńska, Hanna M; Nowak-Wyrzykowska, Małgorzata; Szczepankiewicz, Andrzej A; Dobkowski, Jacek; Dyda, Magdalena; Kamiński, Jarosław; Kołos, Robert

    2011-06-01

    Albumin is commonly applied for blocking the adsorption of other proteins and to prevent the nonspecific adhesion of cells to diverse artificial substrata. Here we address the question of how effective these albumin properties are--by investigating unmodified and sulfonated polystyrene substrata with distinctly different wettabilities. As clearly shown with (125)I-radioisotopic assays, above a concentration of 10-20 μg/mL, the efficiency of bovine serum albumin (BSA) adsorption became markedly higher on the sulfonated surface than on the unmodified one. This study was assisted with the atomic force microscopy. On the unmodified surface, BSA, adsorbed from sufficiently concentrated solutions, formed a monolayer, with occasional intrusions of multilayered patches. Conversely, the arrangement of BSA on the sulfonated surface was chaotic; the height of individual molecules was lower than on the unmodified polystyrene. Importantly, the adhesion study of LNCaP and DU145 cells indicated that both surfaces, subjected to the prior BSA adsorption, did not completely loose their cell-adhesive properties. However, the level of adhesion and the pattern of F-actin organization in adhering cells have shown that cells interacted with unmodified and sulfonated surfaces differently, depending on the arrangement of adsorbed albumin. These results suggest the presence of some bare substratum area accessible for cells after the albumin adsorption to both types of investigated surfaces.

  14. Degradation and contamination of perfluorinated sulfonic acid membrane due to swelling-dehydration cycles

    DEFF Research Database (Denmark)

    Andersen, Shuang Ma; Morgen, Per; Skou, Eivind Morten

    to the membrane degradation in direct methanol fuel cells (DMFCs), where liquid water has direct contact with the electrolyte. An ex-situ experiment was established with swelling-dehydration cycles on the membrane. However, formation of sulfonic anhydride was not detected during the entire treatment; instead...... contamination from calcium was found the primary reason for the deterioration of the membrane properties....

  15. To Bind or to Let Loose: Effectiveness of Sodium Polystyrene Sulfonate in Decreasing Serum Potassium

    Science.gov (United States)

    Sandal, Shaifali; Karachiwala, Hatim; Noviasky, John; Wang, Dongliang; Elliott, William C.; Lehmann, David F.

    2012-01-01

    Background. The use of sodium polystyrene sulfonate in decreasing serum potassium has recently been questioned due to the lack of documented effectiveness. Methods. A retrospective cohort analysis of all hospitalized patients who received sodium polystyrene sulfonate over four months was performed. The change in serum potassium was noted over a period of 24 hours. Patients who received any other form of potassium-altering drug or treatment were excluded. Results. The administration of sodium polystyrene sulfonate reduced serum potassium by 16.7% (P < 0.001) as compared to the baseline serum potassium over a period of 24 hours. During this same time, no change in serum creatinine was identified (P = 0.73). In addition, there was no correlation between potassium and creatinine change (r2 = 0.0004 and P = 0.99). Patients with higher initial serum potassium (≥5.6 mEq/L) reduced their potassium concentration 4% more than those with initial serum potassium of <5.6 mEq/L; however, this reduction did not reach statistical significance (P = 0.32). There was no significant difference in the effectiveness of 15 gm and 30 gm resin preparation (P = 0.54). Thirteen deaths were noted in our cohort, of which one death was due to ischemic colitis. Conclusion. We conclude that sodium polystyrene sulfonate is effective in lowering serum potassium. PMID:23476770

  16. To Bind or to Let Loose: Effectiveness of Sodium Polystyrene Sulfonate in Decreasing Serum Potassium

    Directory of Open Access Journals (Sweden)

    Shaifali Sandal

    2012-01-01

    Full Text Available Background. The use of sodium polystyrene sulfonate in decreasing serum potassium has recently been questioned due to the lack of documented effectiveness. Methods. A retrospective cohort analysis of all hospitalized patients who received sodium polystyrene sulfonate over four months was performed. The change in serum potassium was noted over a period of 24 hours. Patients who received any other form of potassium-altering drug or treatment were excluded. Results. The administration of sodium polystyrene sulfonate reduced serum potassium by 16.7% (P<0.001 as compared to the baseline serum potassium over a period of 24 hours. During this same time, no change in serum creatinine was identified (P=0.73. In addition, there was no correlation between potassium and creatinine change (r2 = 0.0004 and P=0.99. Patients with higher initial serum potassium (≥5.6 mEq/L reduced their potassium concentration 4% more than those with initial serum potassium of <5.6 mEq/L; however, this reduction did not reach statistical significance (P=0.32. There was no significant difference in the effectiveness of 15 gm and 30 gm resin preparation (P=0.54. Thirteen deaths were noted in our cohort, of which one death was due to ischemic colitis. Conclusion. We conclude that sodium polystyrene sulfonate is effective in lowering serum potassium.

  17. Ruthenium(II) and iridium(III) complexes featuring NHC-sulfonate chelate.

    Science.gov (United States)

    Rajaraman, A; Sahoo, A R; Hild, F; Fischmeister, C; Achard, M; Bruneau, C

    2015-10-28

    Three new complexes bearing a chelating (κ(2)C,O) NHC-SO3 ligand have been prepared. An original method for the synthesis of the imidazolium-sulfonate NHC precursor is described. The 5-membered ruthena- and irida-cycle containing complexes were fully characterized and evaluated in a series of catalytic transformations involving hydrogen auto-transfer processes.

  18. Printing properties of the red reactive dyes with different number sulfonate groups on cotton fabric.

    Science.gov (United States)

    Xie, Kongliang; Gao, Aiqin; Li, Min; Wang, Xiao

    2014-01-30

    Cellulose fabric is an important printing substrate. Four red azo reactive dyes based on 1-naphthol-8-amino-3,6-disulfonic acid for cotton fabric printing were designed. Their UV-Vis spectra and printing properties for cotton were investigated. The relationship between the chemical structures of the dyes and their printing properties on cotton fabric was discussed. The results show that the color yield (K/S) values of the printed fabrics decreased with the increase of sulfonate groups, but the fixation and penetration of the reactive dyes on cotton fabric increased. The reactive dyes with fewer number sulfonate groups were sensitive to alkaline and urea. Whereas, the reactive dyes with numerous sulfonate groups were not sensitive to urea and had good leveling properties, penetration uniformity, and good wet fastness for cotton fabric. Surface wettability of all cotton fabrics printed with four dyes was excellent. It is possible to print cotton fabric urea-free using the reactive dyes with numerous sulfonate groups.

  19. Wine metabolomics reveals new sulfonated products in bottled white wines, promoted by small amounts of oxygen.

    Science.gov (United States)

    Arapitsas, Panagiotis; Ugliano, Maurizio; Perenzoni, Daniele; Angeli, Andrea; Pangrazzi, Paolo; Mattivi, Fulvio

    2016-01-15

    The impact of minute amounts of oxygen in the headspace on the post-bottling development of wine is generally considered to be very important, since oxygen can either damage or improve the quality of wine. This project aimed to gain new experimental evidence about the chemistry of the interaction between wine and oxygen. The experimental design included 216 bottles of 12 different white wines produced from 6 different cultivars (Inzolia, Muller Thurgau, Chardonnay, Grillo, Traminer and Pinot gris). Half of them were bottled using the standard industrial process with inert headspace and the other half without inert gas and with extra headspace. After 60 days of storage at room temperature, the wines were analysed using an untargeted LC-MS method. The use of a detailed holistic analysis workflow, with several levels of quality control and marker selection, gave 35 metabolites putatively induced by the different amounts of oxygen. These metabolite markers included ascorbic acid, tartaric acid and various sulfonated compounds observed in wine for the first time (e.g. S-sulfonated cysteine, glutathione and pantetheine; and sulfonated indole-3-lactic acid hexoside and tryptophol). The consumption of SO2 mediated by these sulfonation reactions was promoted by the presence of higher levels of oxygen on bottling.

  20. Assembling structures and dynamics properties of perfluorooctane sulfonate (PFOS) at water-titanium oxide interfaces.

    Science.gov (United States)

    He, Guangzhi; Pan, Gang; Zhang, Meiyi

    2013-09-01

    The surface-associated structures and growth modes of perfluorooctane sulfonate (PFOS) at water-rutile TiO2 interfaces were defined by molecular dynamics (MD) simulations. The results showed that a compact PFOS layer was generated at the rutile surfaces, and the assembling structures and dynamic profiles were crystal-face-dependent. PFOS molecules were attached to the (110) and (001) surfaces mainly by the sulfonate headgroups. A well-defined monolayer was formed on the (110) surface with the perfluorinated alkyl chains nearly perpendicular to the substrate, whereas the C-F chains were inclined at an angle (30-75°) and formed a hemicylinder-like configuration on the (001) surface. On the other hand, the perfluorinated amphiphiles interacted with the (100) plane through both the sulfonate headgroups (relatively strong electrostatic attraction) and the C-F tailgroups (weak van der Waals forces) and yielded an irregular assembling pattern. Water molecules were mostly concentrated more than 17.0 Å away from the solid surfaces and formed a continuous solvent layer, suggesting the super hydrophobicity of perfluorinated alkyl chains. A counterion-bridging mechanism suggested in surfactant adsorption was observed at the molecular scale, where the sulfonate headgroups were linked together by the potassium ions at the surfaces and caused the formation of surface aggregates.

  1. Liquid Crystal Sulfonated Aramids as Proton Exchange Membranes for Fuel Cell Applications

    NARCIS (Netherlands)

    Gao, J.

    2015-01-01

    Two sulfonated aramids, poly(2,2’-disulfonylbenzidine terephthalamide) (PBDT) and poly(2,2’-disulfonylbenzidine isophthalamide) (PBDI) were synthesized with the aim to explore their unique morphology for proton exchange membrane applications. Due to the different polymer structures, PBDT forms a nem

  2. Sulfonic Acid Modified Hollow Silica Spheres and Its Application in Proton Exchange Membranes

    Institute of Scientific and Technical Information of China (English)

    ZHU Min; YUAN Junjie; ZHOU Guangbin

    2011-01-01

    In order to improve the proton conductivity of hollow silica spheres (HSS)/perfluorosulfonic acid ion-exchange (PFSA) composite membranes as proton exchange membrane,sulfonic acid groups were grafted onto the surfaces of HSS via post grafting methods.TEM images and FT-IR spectra of the obtained sulfonic acid groups modified hollow silica spheres (SAMHSS) illustrated that the sulfonic acid groups were successfully grafted onto the surfaces of HSS.Water uptake and swelling degree of SAMHSS/PFSA composite membranes were found much higher than those of HSS/PFSA membranes due to the introduction of hydrophilic sulfonic acid groups.In a range from 50 ℃C to 130 ℃,the highest conductivity of composite membranes was obtained when 5 wt% SAMHSS was loaded.The maximum conductivity reached 7.5×10-2S·cm-1 at 100 ℃C and 100% relative humidity,even the temperature increased to 130 ℃,the conductivity of composite membranes with 5 wt% SAMHSS could reach 3.7× 10-2 S·cm-1 at 100 % relative humidity,while the conductivity of the recast PFSA was only 2.2x 10-3 S·cm-1.

  3. Synthesis and ATRP of novel fluorinated aromatic monomer with pendant sulfonate group

    DEFF Research Database (Denmark)

    Dimitrov, Ivaylo; Jankova Atanasova, Katja; Hvilsted, Søren

    2013-01-01

    Novel, fluorinated monomer with pendant sulfonate group was synthesized utilizing a two-step derivatization of 2,3,4,5,6-pentafluorostyrene (FS). The first step was a nucleophilic substitution of the fluorine atom in para position by hydroxyl group followed by sulfopropylation. The monomer was po...

  4. Thin sulfonated poly(ether ether ketone) films for the dehydration of compressed carbon dioxide

    NARCIS (Netherlands)

    Koziara, B.T.

    2015-01-01

    In this thesis, the properties of thin films from highly sulfonated poly(ether ether ketone) (SPEEK) have been investigated within the context of their application as membranes for the dehydration of compressed carbon dioxide. Spectroscopic ellipsometry has been used as the predominant measurement t

  5. Synthesis of sulfonated porous carbon nanospheres solid acid by a facile chemical activation route

    Science.gov (United States)

    Chang, Binbin; Guo, Yanzhen; Yin, Hang; Zhang, Shouren; Yang, Baocheng

    2015-01-01

    Generally, porous carbon nanospheres materials are usually prepared via a template method, which is a multi-steps and high-cost strategy. Here, we reported a porous carbon nanosphere solid acid with high surface area and superior porosity, as well as uniform nanospheical morphology, which prepared by a facile chemical activation with ZnCl2 using resorcinol-formaldehyde (RF) resins spheres as precursor. The activation of RF resins spheres by ZnCl2 at 400 °C brought high surface area and large volume, and simultaneously retained numerous oxygen-containing and hydrogen-containing groups due to the relatively low processing temperature. The presence of these functional groups is favorable for the modification of -SO3H groups by a followed sulfonation treating with sulphuric acid and organic sulfonic acid. The results of N2 adsorption-desorption and electron microscopy clearly showed the preservation of porous structure and nanospherical morphology. Infrared spectra certified the variation of surface functional groups after activation and the successful modification of -SO3H groups after sulfonation. The acidities of catalysts were estimated by an indirect titration method and the modified amount of -SO3H groups were examined by energy dispersive spectra. The results suggested sulfonated porous carbon nanospheres catalysts possessed high acidities and -SO3H densities, which endowed their significantly catalytic activities for biodiesel production. Furthermore, their excellent stability and recycling property were also demonstrated by five consecutive cycles.

  6. Double lawton SN2'addition to epoxyvinyl sulfones: selective construction of the stereotetrads of aplyronine A.

    Science.gov (United States)

    El-Awa, Ahmad; Fuchs, Philip

    2006-07-06

    [reaction: see text] Enantiopure epoxyvinyl sulfones function as templates for the diastereoselective construction of the three stereotetrads of aplyronine A. Lawton S(N)2' addition of 3,5-dimethylpyrazole followed by its displacement in an alcohol-directed Lawton S(N)2' reaction establishes the required product stereochemistry with high selectivity.

  7. Sulfonated graphene oxide as effective catalyst for conversion of 5-(hydroxymethyl)-2-furfural into biofuels.

    Science.gov (United States)

    Antunes, Margarida M; Russo, Patrícia A; Wiper, Paul V; Veiga, Jacinto M; Pillinger, Martyn; Mafra, Luís; Evtuguin, Dmitry V; Pinna, Nicola; Valente, Anabela A

    2014-03-01

    The acid-catalyzed reaction of 5-(hydroxymethyl)-2-furfural with ethanol is a promising route to produce biofuels or fuel additives within the carbohydrate platform; specifically, this reaction may give 5-ethoxymethylfurfural, 5-(ethoxymethyl)furfural diethylacetal, and/or ethyl levulinate (bioEs). It is shown that sulfonated, partially reduced graphene oxide (S-RGO) exhibits a more superior catalytic performance for the production of bioEs than several other acid catalysts, which include sulfonated carbons and the commercial acid resin Amberlyst-15, which has a much higher sulfonic acid content and stronger acidity. This was attributed to the cooperative effects of the sulfonic acid groups and other types of acid sites (e.g., carboxylic acids), and to the enhanced accessibility to the active sites as a result of the 2D structure. Moreover, the acidic functionalities bonded to the S-RGO surface were more stable under the catalytic reaction conditions than those of the other solids tested, which allowed its efficient reuse.

  8. Selective oxidations of a dithiolate complex produce a mixed sulfonate/thiolate complex.

    Science.gov (United States)

    Chohan, Balwant S; Maroney, Michael J

    2006-03-06

    Oxygenation or peroxidation of a planar, tetracoordinate, low-spin nickel(II) complex of a N2S2-donor ligand, (N,N'-dimethyl-N,N'-bis(2-mecaptoethyl)-1, 3-propanediaminato)nickel(II), proceeds via the formation of a mixed sulfinate/thiolate complex and leads to the production of a novel dimeric complex containing both sulfonate and thiolate ligands. Thus, reaction proceeds via selective oxidation of the sulfinate sulfur atom, leaving the thiolate reduced. The novel sulfonate/thiolate complex has been isolated and characterized by electospray ionization mass spectrometry and single-crystal X-ray diffraction. Crystals form in the monoclinic space group P2(1)/c with cell dimensions a = 8.4647(12) A, b = 12.592(3) A, and c = 12.531(2) A, angles alpha = gamma = 90 degrees and beta = 106.645(11) degrees , and Z = 2. The structure was refined to R = 5.20% and R(w) = 12.86% [I > 2sigma(I)]. The isolation of this mixed sulfonate/thiolate complex from oxidation of a mixed sulfinate/thiolate complex provides experimental evidence for the formation of a sulfonate ligand via a Ni-O-O-SO2R intermediate, as suggested by recent density functional theory calculations.

  9. Alquilbenzeno sulfonato linear: uma abordagem ambiental e analítica

    Directory of Open Access Journals (Sweden)

    José Carlos P. Penteado

    2006-10-01

    Full Text Available The environmental impact of detergents and other consumer products is behind the continued interest in the chemistry of the surfactants used. Of these, linear alkylbenzene sulfonates (LASs are most widely employed in detergent formulations. The precursors to LASs are linear alkylbenzenes (LABs. There is also interest in the chemistry of these hydrocarbons, because they are usually present in commercial LASs (due to incomplete sulfonation, or form as one of their degradation products. Additionally, they may be employed as molecular tracers of domestic waste in the aquatic environment. The following aspects are covered in the present review: The chemistry of surfactants, in particular LAS; environmental impact of the production of LAS; environmental and toxicological effects of LAS; mechanisms of removal of LAS in the environment, and methods for monitoring LAS and LAB, the latter in domestic wastes. Classical and novel analytical methods employed for the determination of LAS and LAB are discussed in detail, and a brief comment on detergents in Brazil is given.

  10. Alquilbenzeno sulfonato linear: uma abordagem ambiental e analítica

    Directory of Open Access Journals (Sweden)

    Penteado José Carlos P.

    2006-01-01

    Full Text Available The environmental impact of detergents and other consumer products is behind the continued interest in the chemistry of the surfactants used. Of these, linear alkylbenzene sulfonates (LASs are most widely employed in detergent formulations. The precursors to LASs are linear alkylbenzenes (LABs. There is also interest in the chemistry of these hydrocarbons, because they are usually present in commercial LASs (due to incomplete sulfonation, or form as one of their degradation products. Additionally, they may be employed as molecular tracers of domestic waste in the aquatic environment. The following aspects are covered in the present review: The chemistry of surfactants, in particular LAS; environmental impact of the production of LAS; environmental and toxicological effects of LAS; mechanisms of removal of LAS in the environment, and methods for monitoring LAS and LAB, the latter in domestic wastes. Classical and novel analytical methods employed for the determination of LAS and LAB are discussed in detail, and a brief comment on detergents in Brazil is given.

  11. Sulfonated poly(2,5-benzimidazole) (SABPBI) impregnated with phosphoric acid as proton conducting membranes for polymer electrolyte fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Asensio, J.A. [Institut de Ciencia de Materials de Barcelona, Bellaterra (Spain); Universitat Ramon Llull, Barcelona (Spain). Inst. Quimic de Sarria; Borros, S. [Universitat Ramon Llull, Barcelona (Spain). Inst. Quimic de Sarria; Gomez-Romero, P. [Institut de Ciencia de Materials de Barcelona, Bellaterra (Spain)

    2004-10-01

    Previously cast ABPBI membranes were sulfonated by doping with sulfuric acid followed by heat treatment at 450 {sup o}C for 5 min in air. Sulfonation degrees between 35 and 49% of the benzimidazole rings were achieved. The resulting SABPBI membranes were impregnated with phosphoric acid (H{sub 3}PO{sub 4} 85%/H{sub 2}O, 70:30 bath). For concentrated phosphoric acid baths (above 65%), the capacity of these membranes for phosphoric acid uptake (and consequently also their conductivity) increased with the degree of sulfonation. Sulfonated and acid doped SABPBI membranes were characterized in terms of degree of sulfonation, thermal stability (TGA), X-ray diffraction, FTIR spectroscopy and proton conductivity in the dry state, and compared with phosphoric acid impregnated ABPBI studied earlier. The maximum conductivity measured in dry conditions was 3.5x10{sup -2} S cm{sup -2} at 185 {sup o}C for SABPBI 4.6H{sub 3}PO{sub 4} (with a degree of sulfonation of 41%) which compares favorably with non-sulfonated ABPBI and makes feasible their application in PEM Fuel Cells working at temperatures of 150-200 {sup o}C. (Author)

  12. Fast Breaking Detergents: Their Role in the Generation of Hydrogen Sulfide in Oily-Water Wastes

    Science.gov (United States)

    1993-09-01

    4.1 Biodegradation of Detergents Linear alkylbenzene sulfonates , which are present in "Comprox", have been widely used for some decades, so the... alkylbenzene sulfonate . This can be degraded by oxidation of either the alkyl chain or the benzene ring. Both reactions initially require oxygen (Swisher...1968) Biodegradation of linear alkylated sulfonates . Environmental Science and Technology, 2, 773-778. Hodgeman, D.K.C. Fletcher, L. E. and Upsher, F

  13. Mass transport of direct methanol fuel cell species in sulfonated poly(ether ether ketone) membranes

    Energy Technology Data Exchange (ETDEWEB)

    Silva, V.S.; Boaventura, M.; Mendes, A.M.; Madeira, L.M. [LEPAE, Chemical Engineering Department, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); Ruffmann, B.; Vetter, S.; Nunes, S.P. [GKSS Research Centre, Max-Planck Str., 21502 Geesthacht (Germany)

    2006-05-05

    Homogeneous membranes based on sulfonated poly(ether ether ketone) (sPEEK) with different sulfonation degrees (SD) were prepared and characterized. In order to perform a critical analysis of the SD effect on the polymer barrier and mass transport properties towards direct methanol fuel cell species, proton conductivity, water/methanol pervaporation and nitrogen/oxygen/carbon dioxide pressure rise method experiments are proposed. This procedure allows the evaluation of the individual permeability coefficients in hydrated sPEEK membranes with different sulfonation degrees. Nafion{sup (R)} 112 was used as reference material. DMFC tests were also performed at 50{sup o}C. It was observed that the proton conductivity and the permeability towards water, methanol, oxygen and carbon dioxide increase with the sPEEK sulfonation degree. In contrast, the SD seems to not affect the nitrogen permeability coefficient. In terms of selectivity, it was observed that the carbon dioxide/oxygen selectivity increases with the sPEEK SD. In contrast, the nitrogen/oxygen selectivity decreases. In terms of barrier properties for preventing the DMFC reactants loss, the polymer electrolyte membrane based on the sulfonated poly(ether ether ketone) with SD lower or equal to 71%, although having slightly lower proton conductivity, presented much better characteristics for fuel cell applications compared with the well known Nafion{sup (R)} 112. In terms of the DMFC tests of the studied membranes at low temperature, the sPEEK membrane with SD=71% showed to have similar performance, or even better, as that of Nafion{sup (R)} 112. However, the highest DMFC overall efficiency was achieved using sPEEK membrane with SD=52%. (author)

  14. Microbial toxicity and biodegradability of perfluorooctane sulfonate (PFOS) and shorter chain perfluoroalkyl and polyfluoroalkyl substances (PFASs).

    Science.gov (United States)

    Ochoa-Herrera, Valeria; Field, Jim A; Luna-Velasco, Antonia; Sierra-Alvarez, Reyes

    2016-09-14

    Perfluorooctane sulfonate (PFOS) and related perfluoroalkyl and polyfluoroalkyl substances (PFASs) are emerging contaminants that have been widely applied in consumer and industrial applications for decades. However, PFOS has raised public concern due to its high bioaccumulative character, environmental persistence, and toxicity. Shorter PFASs such as perfluorobutane sulfonate (PFBS) and polyfluoroalkyl compounds have been proposed as alternatives to PFOS but it is unclear whether these fluorinated substances pose a risk for public health and the environment. The objective of this research was to investigate the microbial toxicity and the susceptibility to microbial degradation of PFOS and several related fluorinated compounds, i.e., short-chain perfluoroalkyl and polyfluoroalkyl sulfonic and carboxylic acids. None of the compounds tested were toxic to the methanogenic activity of anaerobic wastewater sludge even at very high concentrations (up to 500 mg L(-1)). All PFASs evaluated were highly resistant to microbial degradation. PFOS was not reductively dehalogenated by the anaerobic microbial consortium even after very long periods of incubation (3.4 years). Similarly, the tested short chain perfluoroalkyl substances (i.e., PFBS and trifluoroacetic acid) and a polyfluoroalkyl PFOS analogue, 6 : 2 fluorotelomer sulfonic acid (FTSA) were also resistant to anaerobic biodegradation. Likewise, no conclusive evidence of microbial degradation was observed under aerobic conditions for any of the short-chain perfluoroalkyl and polyfluoroalkyl carboxylic acids tested after 32 weeks of incubation. Collectively, these results indicate that PFOS and its alternatives such as short chain perfluoroalkyl sulfonates and carboxylates and their polyfluorinated homologues are highly resistant to microbial degradation.

  15. Structural transformation of cytochrome c and apo cytochrome c induced by sulfonated polystyrene.

    Science.gov (United States)

    Gong, Jie; Yao, Ping; Duan, Hongwei; Jiang, Ming; Gu, Shaohua; Chunyu, Lijuan

    2003-01-01

    The structural transformation of cytochrome c (cyt c) and its heme-free precursor, apo cyt c, induced by negatively charged sulfonated polystyrene (SPS) with different charge density (degree of sulfonation) and chain length was studied to understand the factors that influence the folding and unfolding of the protein. SPS forms stable transparent nanoparticles in aqueous solution. The hydrophobic association of the backbone chain and phenyl groups is balanced by the electrostatic repulsion of the sulfonate groups on the particle surface. The binding of cyt c to negatively charged SPS particles causes an extensive disruption of the native compact structure of cyt c: the cleavage of Fe-Met80 ligand, about 40% loss of the helical structure, and the disruption of the asymmetry environment of Trp59. On the other hand, SPS particle-bound apo cyt c undergoes a conformational change from the random coil to alpha-helical structure. The folding of apo cyt c in SPS particles was influenced by pH and ionic strength of the solution, SPS concentration, and the degree of sulfonation and chain length of SPS. The folding can reach more than 90% of the alpha-helix content of native cyt c in solution. Poly(sodium 4-styrenesulfonate) (PSS), which is 100% sulfonated polystyrene and cannot form hydrophobic cores in the solution, induces only two-thirds of the alpha-helix content compared with SPS. It appears that the electrostatic interaction between PSS/SPS and apo cyt c induces an early partially folded state of apo cyt c. The hydrophobic interaction between nonpolar residues in apo cyt c and the hydrophobic cores in SPS particles extends the alpha-helical structure of apo cyt c.

  16. Synthesis of sulfonated porous carbon nanospheres solid acid by a facile chemical activation route

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Binbin, E-mail: changbinbin806@163.com; Guo, Yanzhen; Yin, Hang; Zhang, Shouren; Yang, Baocheng, E-mail: baochengyang@yahoo.com

    2015-01-15

    Generally, porous carbon nanospheres materials are usually prepared via a template method, which is a multi-steps and high-cost strategy. Here, we reported a porous carbon nanosphere solid acid with high surface area and superior porosity, as well as uniform nanospheical morphology, which prepared by a facile chemical activation with ZnCl{sub 2} using resorcinol-formaldehyde (RF) resins spheres as precursor. The activation of RF resins spheres by ZnCl{sub 2} at 400 °C brought high surface area and large volume, and simultaneously retained numerous oxygen-containing and hydrogen-containing groups due to the relatively low processing temperature. The presence of these functional groups is favorable for the modification of –SO{sub 3}H groups by a followed sulfonation treating with sulphuric acid and organic sulfonic acid. The results of N{sub 2} adsorption–desorption and electron microscopy clearly showed the preservation of porous structure and nanospherical morphology. Infrared spectra certified the variation of surface functional groups after activation and the successful modification of –SO{sub 3}H groups after sulfonation. The acidities of catalysts were estimated by an indirect titration method and the modified amount of –SO{sub 3}H groups were examined by energy dispersive spectra. The results suggested sulfonated porous carbon nanospheres catalysts possessed high acidities and –SO{sub 3}H densities, which endowed their significantly catalytic activities for biodiesel production. Furthermore, their excellent stability and recycling property were also demonstrated by five consecutive cycles. - Graphical abstract: Sulfonated porous carbon nanospheres with high surface area and superior catalytic performance were prepared by a facile chemical activation route. - Highlights: • Porous carbon spheres solid acid prepared by a facile chemical activation. • It owns high surface area, superior porosity and uniform spherical morphology. • It possesses

  17. Las ruinas y las sombras de Manderley

    Directory of Open Access Journals (Sweden)

    Donapetry Camacho, María

    2010-02-01

    Full Text Available The ruins and the shadows of Manderley explores possible reciprocal interpretative relations between Daphne du Maurier’s novel Rebecca and Alfred Hitchcock’s cinematic version. Some of the relevant aspects considered here are: the treatment of the Derridean “ruins of memory” within the novel and within Hitchcock himself, the differentiation and the confrontation of the protagonist as outsider vis á vis the world of Manderley’s insiders, the iconic and symbolic values of the literary text and its filmic visualization, and the ethical positions implied by the choice or rejection of certain narrative devices in both works.

    Las ruinas y las sombras de Manderley aborda posibles relaciones interpretativas recíprocas entre la novela de Daphne du Maurier Rebecca y la película homónima de Alfred Hitchcock. Algunos de los aspectos que se consideran relevantes en este estudio son: el tratamiento de las “ruinas de la memoria” derridianas dentro de la novela y del propio Hitchcock, la diferenciación y el enfrentamiento de la protagonista “externa” con el mundo de los “internos” de Manderley, los valores icónicos y simbólicos del texto literario y de la visualización fílmica, y las posiciones éticas que implican la elección o el rechazo de ciertos recursos narrativos en ambas obras.

  18. Haciendo resonar las voces

    DEFF Research Database (Denmark)

    Tufte, Thomas; Corrigan, Arran; Ekstrøm, Ylva

    2011-01-01

    sexualidad protegida y el VIH/SIDA”. FEMINA persigue sus objetivos por medio de la producción de dos de las revistas de mayor circulación en Tanzania: SiMchezo! y Fema, apuntando a la juventud rural y urbana mediante una estrategia de intervención comunicacional multimedia y participativa. Las dos revistas...

  19. en las redes organizacionales

    Directory of Open Access Journals (Sweden)

    Tania Peña

    2006-01-01

    Full Text Available Partiendo de una perspectiva racional, que luego llega a la abducción, se analiza la contribución de las unidades de información en las redes organizacionales generadoras de conocimiento; para esto se manejan algunos postulados teóricos que caracterizan y señalan tanto las funciones de las unidades de información en la actual sociedad globalizada, como el funcionamiento de las redes organizacionales. Como resultado se indica que las unidades de información contribuyen en los procesos de transferencia y creación de conocimiento que ocurre en dichas redes, en tanto que su acción impacta positivamente el desempeño de sus participantes. Se concluye primordialmente que las unidades de información propician el incremento del potencial creativo de los individuos que se manejan en ambientes redificados, por cuanto le proporcionan herramientas instrumentales tecnológico- analíticas para hacer un uso más provechoso de las fuentes de información, por lo que agregan valor a sus aportes intelectuales en la solución de problemas, el mejoramiento de procesos o la creación de innovaciones.

  20. Causas de las discapacidades

    OpenAIRE

    Jiménez Lara, Antonio; Huete García, Agustín

    2002-01-01

    En este documento se ofrece información sobre las causas de las deficiencias, clasificadas de acuerdo con la siguiente categorización: congénito; problemas en el parto; accidente de tráfico; accidente doméstico; accidente de ocio; accidente laboral; otro tipo de accidente; enfermedad común; enfermedad profesional y otras causas.

  1. The toxicity of the quaternary ammonium compound benzalkonium chloride alone and in mixtures with other anionic compounds to bacteria in test systems with Vibrio fischeri and Pseudomonas putida.

    Science.gov (United States)

    Sütterlin, H; Alexy, R; Kümmerer, K

    2008-10-01

    Mixtures of chemicals are present in the aquatic environment but standard testing methods assess only single compounds. One aspect of this question is the importance of the formation of ionic pairs, for example from quaternary ammonium compounds with organic anions, and the significance of the ionic pairs for bacterial toxicity in the aquatic environment. The aim of the present study was to investigate the toxicity of the cationic quaternary ammonium compound benzalkonium chloride (BAC) against aquatic bacteria in the presence of substances commonly found in wastewater, such as the anionic surfactant linear alkylbenzene sulfonate (LAS), naphthalene sulfonic acid (NSA), sodium dodecylsulfonate (SDS), and benzene sulfonic acid (BSA). The growth inhibition test with Pseudomonas putida and the Vibrio fischeri luminescent inhibition test were used to determine the toxicity of single compounds and compound mixtures. The results found in this study indicate that ion pair formation is of minor significance under the test conditions applied here.

  2. Las neurosis actuales y las psicosis ordinarias

    OpenAIRE

    Aguirre, Javier

    2013-01-01

    El trabajo tiene por finalidad poner en tensión las categorías de psicosis ordinaria y neurosis actuales. En primer lugar, se procede a examinar ambas categorías para luego establecer sus puntos de coincidencia y disidencia. Se concluye que la categoría de neurosis actual propuesta por Freud, es una posible expresión de lo que en la actualidad se llama psicosis ordinaria.

  3. 磺化聚芳醚酮砜的热降解动力学%The Thermal Degradation Kinetics of Sulfonated Poly(Aryl Ether Ketone Sulfone)

    Institute of Scientific and Technical Information of China (English)

    王哲; 杨鑫; 吴清海; 倪宏哲; 周杰

    2011-01-01

    The thermal behaviors of sulfonated poly(aryl ether ketone sulfone)(SPAEKS) as a proton exchange membrane materials was researched by therrnogravimetry analysis (TGA). The thermal degradation kinetics of SPAEKS before sulfonic acid groups completely splitting off was investigated at different heating rates in N2 by Kissinger method and Flynn-Wall-Ozawa method. The activation energy E, pre-exponential factor A, reaction order n and correlation coefficient r of SPAEKS with different degrees of sulfonation (DS) were calculated by Kissinger method(E,lnA,n and r of SPAEKS-4 are 149.16 kJ/mol, 23.93, 2.6 and 0.9887, respectively). The activation energy E of SPAEKS with different DS was calculated by Flynn-Wall-Ozawa method (E of SPAEKS-4 is 140.73 kJ/mol ), which is lower than that was calculation by Kissinger method in the same DS. The calculated activation energy of SPAEKS by above two methods increases with the increasment of DS.%通过热重分析仪(TGA)对作为质子交换膜材料使用的磺化聚芳醚酮砜(SPAEKS)进行了热性能研究.采用不同的升温速率,分别用Kissinger方法和Flynn-Wall-Ozawa方法研究了不同磺化度的SPAEKS在氮气氛围下磺酸基团完全脱落前的热降解动力学.研究表明,通过Kissinger方法计算得到SPAEKS的活化能E、指前因子A、反应级数η、相关系数r(磺化度0.8的SPAEKS-4,E=149.16 kJ/mol,InA=23.93,n=2.6,r=0.9887).通过Flynn-Wall-Ozawa方法计算得到SPAEKS的平均活化能E(SPAEKS-4的活化能为140.73 kJ/mol),而且所求活化能在相同磺化度下略低于用Kissinger方法所求,但活化能都随着磺化度的增加而增大.

  4. Las drogas en Galicia

    OpenAIRE

    Bermejo Barrera, Ana María

    2012-01-01

    Las drogas de abuso han sido consumidas desde los tiempos más remotos, siendo en aquel enton­ ces su uso muy restringido, por la poca disponibilidad de las mismas, a rituales místico-religiosos y a tratamiento de algunas enfermedades. Con la revolución industrial en el siglo XIX, los labora­ torios farmacéuticos extraen los principios activos de las plantas y sintetizan sus derivados, pasan­ do a ser consumidas en mayor escala. La década de los sesenta fue marcada por el aum...

  5. Las Leyes de Newton

    OpenAIRE

    González S., Fabio

    2015-01-01

    La labor de Newton en el campo de la física, una de las piedras angulares en que se fundamenta esta ciencia, se caracteriza por el hecho de que a partir de unos enunciados básicos explica los diversos fenómenos que estudia la mecánica. Entre las grandes contribuciones de Newton se pueden citar: el descubrimiento de la ley de la gravitación universal, el enunciado de las leyes del movimiento, el teorema del binomio, la formulación básica del cálculo diferencial e integral, así-como algunos tra...

  6. COMPOSITE OF CHITOSAN VANILIN / SULFONATED POLYSTYRENE AS POLYMER ELECTROLYTE MEMBRANES : CATIONIC EXCHANGE CAPACITY, SWELLING DEGREE AND THERMAL PROPERTIES

    OpenAIRE

    Edi Pramono; Candra Purnawan; Yuniawan Hidayat; Jati Wulansari; Sayekti Wahyuningsih

    2016-01-01

    Research on the preparation and characterization of sulfonated polystyrene (PST) /chitosan vanillin (KV) composite as electrolyte membranes has been conducted in order to investigate the effect of PST and KV composition to its chemical and physical properties. Polystyrene was modified by sulfonation reaction to produces PST, meanwhile chitosan was modified by schift base reaction to produces KV. The composite membranes were prepared by casting method and were characterized in order to identi...

  7. Use of albendazole sulfoxide, albendazole sulfone, and combined solutions as scolicidal agents on hydatid cysts ( in vitro study)

    Institute of Scientific and Technical Information of China (English)

    Gokhan Adas; Soykan Arikan; Ozgur Kemik; Ali Oner; Nilgun Sahip; Oguzhan Karatepe

    2009-01-01

    AIM: To establish which scolicidal agents are superior and more suitable for regular use.METHODS: Echinococcus granulosus protoscoleces were obtained from 25 patients with liver hydatid cysts. Various concentrations of albendazole sulfone,albendazole sulfoxide, and albendazole sulfone and albendazole sulfoxide mixed together in concentrations of 50 μg/mL, and H2O2 in a concentration of 4%, NaCl 20%, and 1.5% cetrimide-0.15% chlorhexidine (10% Savlon-Turkey) were used to determine the scolicidal effects. Albendazole (ABZ) derivatives and other scolicidal agents were applied to a minimum of 100 scoleces for 5 and 10 min. The degree of viability was calculated according to the number of living scolices per field from a total of 100 scolices observed under the microscope.RESULTS: After 5 min, ABZ sulfone was 97.3% effective, ABZ sulfoxide was 98.4% effective, and the combined solution was 98.6% effective. When sulfone, sulfoxide and the combined solutions were compared,the combined solution seemed more effective than sulfone. However, there was no difference when the combined solution was compared with sulfoxide. After 10 min, hypertonic salt water, sulfone, sulfoxide, and the combined solution compared to other solutions looked more effective and this was statistically significant on an advanced level. When sulfone,sulfoxide, and the combined solutions were compared with each other, the combined solution appeared more effective than sulfone. When the combined solution was compared with sulfoxide, there was no difference.CONCLUSION: Despite being active, ABZ metabolites did not provide a marked advantage over 20% hypertonic saline. According to these results, we think creating a newly improved and more active preparation is necessary for hydatid cyst treatment.

  8. Use of sodium polystyrene sulfonate in an acute-on-chronic lithium poisoned patient:A case report

    Institute of Scientific and Technical Information of China (English)

    Chakroun-Walha Olfa; Ksibi Hichem; Rejeb Imen; Boujelben Mariem; Chaari Adel; Chtara Kamilia; Bouaziz Mounir; Rekik Noureddine

    2016-01-01

    A 35-year-old woman with an acute-on-chronic lithium overdose received multiple oral doses of sodium polystyrene sulfonate totaling 120 g over a 24-h period. During the 72 h after the institution of therapy, the serum lithium level decreased from 3.80 to 0.42 mEq/L. Multiple doses of sodium polystyrene sulfonate may be useful in lowering the serum lithium level in severely ill patients with acute renal failure, and can substitute hemodialysis.

  9. y las comunicaciones

    Directory of Open Access Journals (Sweden)

    Lucio Fuentelsaz

    2005-01-01

    Full Text Available Las Tecnologías de la Información y las Comunicaciones (TIC están en todas partes incluso en las estadísticas de productividad. Esta afirmación, a modo de antítesis de la proposición formulada por el premio Nobel Robert Solow, constituye el punto de partida de este trabajo que se enmarca dentro de una corriente de investigación que ha sido objeto de abundantes estudios en los últimos años y cuyo propósito fundamental es analizar los determinantes de la relación entre la inversión en TIC y las mejoras en la productividad empresarial.

  10. Aviso para las viudas.

    Directory of Open Access Journals (Sweden)

    Francisco de Sales

    2000-01-01

    Full Text Available San Pablo instruye todos los prelados en la persona de su Timoteo, diciendo: «Honra las viudas que son verdaderamente viudas». Para ser, pues, verdaderamente viuda, son necesarias estas cosas

  11. las relaciones interpersonales

    Directory of Open Access Journals (Sweden)

    Juan Gabriel Gómez Albarello

    2011-01-01

    Full Text Available En este ensayo discuto el efecto que han tenido las filtraciones realizadas por WikiLeaks en las relaciones internacionales y en las relaciones interpersonales. Sostengo que Wikileaks motivará a muchos a continuar con la práctica de tales filtraciones y que esa motivación proviene de la justificación de esa práctica en dos conjuntos de valores: la ética del hacker y los valores democráticos. También afirmo que el efecto de esas filtraciones puede causar un impacto profundo en la esfera de la cultura puesto que la evaluación de la conducta de los estadistas se realiza usualmente mediante de analogías basadas en la experiencia interpersonal. Luego de presentar argumentos en favor de decir la verdad en las relaciones personales, concluyo destacando la forma como se engranan varios tipos de argumentos.

  12. Las vacas imitadores expertos

    OpenAIRE

    Chevalier, Pedro

    2009-01-01

    La mayoría de las especies del género Hypoplectrus presentan un comportamiento conocido como mimetismo agresivo. Este fenómeno consiste en la imitación de los patrones de coloración, por parte de las vacas, de peces que no son depredadores de crustáceos y pequeños peces. Al imitar el color de peces inofensivos pueden acercarse a sus presas sin que estas huyan.

  13. Las vitrinas del museo

    OpenAIRE

    2010-01-01

    Tanto las obras de arte como los animales nos ocultan información cuando se reúnen en un museo, pues quedan al margen del contexto espacial y temporal del que proceden. No obstante, el ojo avezado sabrá interpretar una parte de esa historia perdida. Del mismo modo, algunas especies vivas traslocadas conservan rasgos que nos ayudan a inferir las condiciones ambientales de su lugar de origen.

  14. Direct esterification of olive-pomace oil using mesoporous silica supported sulfonic acids

    Directory of Open Access Journals (Sweden)

    F. Alrouh

    2017-02-01

    Full Text Available Mesoporous silica MCM-41 and SBA-15 containing propyl sulfonic acid groups were synthesized according to the literature and were characterized by X-ray diffraction, N2 adsorption and the H+ exchange capacities of the sulfonic acid groups were titrated. The esterification reaction of glycerol with olive-pomace oil has been carried out by using prepared functionalized mesoporous silica (MCM-41 and SBA-15 as catalysts. It has been monitored by GC two fatty acids (palmitic and oleic acids as reactants in olive-pomace oil and their related monoacylglycerols (Glycerol monopalmitate GMP and monooleate GMO as reaction product. The catalytic activities of the functionalized mesoporous silica were compared with commercial catalysts, these included homogeneous catalysts (p-toluenesulfonic acid and heterogeneous catalysts (Amberlyst-15. The total yield of monoacylglycerols (GMO + GMP was nearly 40%. Remarkably, we found that MCM-41-SO3H was recycled at least 3 times without any loss of activity.

  15. Epoxidation of 1-Octene with hydrogen peroxide aqueous catalyzed by titania supported sulfonated coal

    Science.gov (United States)

    Nurhadi, Mukhamad

    2017-02-01

    Titania supported sulfonated coal was created as heterogeneous catalyst for epoxidation of 1-octene with aqueous hydrogen peroxide as oxidant at room temperature. The catalysts were prepared from coal that was sulfonated with H2SO4 (97%) and impregnated 7.2%wt with titanium(IV) isopropoxide (Ti(PrO)4). All catalysts coal (C), CS, Ti(7.2)-CS and Ti(7.2)-CSC were characterized by FTIR. The catalytic performance was tested for epoxidation of 1-octene with H2O2 aqueous as oxidant. It is found that Ti(7.2)-CS possessed the best catalytic performance and it gave the highest 1,2 epoxyoctene 322 µmol.

  16. Sulfonated poly(tetramethydiphenyl ether ether ketone) membranes for vanadium redox flow battery application

    Science.gov (United States)

    Mai, Zhensheng; Zhang, Huamin; Li, Xianfeng; Bi, Cheng; Dai, Hua

    Sulfonated poly(tetramethydiphenyl ether ether ketone) (SPEEK) with various degree of sulfonation is prepared and first used as ion exchange membrane for vanadium redox flow battery (VRB) application. The vanadium ion permeability of SPEEK40 membrane is one order of magnitude lower than that of Nafion 115 membrane. The low cost SPEEK membranes exhibit a better performance than Nafion at the same operating condition. VRB single cells with SPEEK membranes show very high energy efficiency (>84%), comparable to that of the Nafion, but at much higher columbic efficiency (>97%). In the self-discharge test, the duration of the cell with the SPEEK membrane is two times longer than that with Nafion 115. The membrane keeps a stable performance after 80-cycles charge-discharge test.

  17. Sulfonate-grafted porous polymer networks for preferential CO2 adsorption at low pressure.

    Science.gov (United States)

    Lu, Weigang; Yuan, Daqiang; Sculley, Julian; Zhao, Dan; Krishna, Rajamani; Zhou, Hong-Cai

    2011-11-16

    A porous polymer network (PPN) grafted with sulfonic acid (PPN-6-SO(3)H) and its lithium salt (PPN-6-SO(3)Li) exhibit significant increases in isosteric heats of CO(2) adsorption and CO(2)-uptake capacities. IAST calculations using single-component-isotherm data and a 15/85 CO(2)/N(2) ratio at 295 K and 1 bar revealed that the sulfonate-grafted PPN-6 networks show exceptionally high adsorption selectivity for CO(2) over N(2) (155 and 414 for PPN-6-SO(3)H and PPN-6-SO(3)Li, respectively). Since these PPNs also possess ultrahigh physicochemical stability, practical applications in postcombustion capture of CO(2) lie well within the realm of possibility.

  18. The Role of Neutralizing Ion Type on the Dynamics of Sulfonated Polystyrene Ionomers

    Science.gov (United States)

    Castagna, Alicia; Wang, Wenqin; Winey, Karen I.; Runt, James

    2011-03-01

    Sulfonated polystyrene (SPS) ionomers neutralized with Na, Cs, and Zn were investigated using scanning transmission electron microscopy (STEM), X-ray scattering, and dielectric relaxation spectroscopy. The role of the neutralizing ion on the structure and molecular dynamics will be discussed as a function of sulfonation level. STEM and X-ray scattering revealed the presence of spherical aggregates 2 nm in diameter. Successful fitting of the scattering data to the Kinning-Thomas modified hardsphere model provides additional information on aggregate size, number density and radius of closest approach. The dynamics of these materials, as revealed by DRS, are highly sensitive to the neutralizing ion, in particular, the character of the segmental relaxation, i.e. relaxation time, breadth and number of relaxations. Additionally, the relaxation time of the Maxwell-Wagner-Sillars interfacial polarization process at high temperatures is also highly dependent on neutralization and ion character.

  19. Conformation of Randomly Sulfonated Pentablock Ionomers in Dilute Solution: Molecular Dynamic Simulation Study

    Science.gov (United States)

    Aryal, Dipak; Perahia, Dvora; Grest, Gary S.

    2011-03-01

    As part of our efforts to define the factors that control the structure and dynamics of structures ionic polymers, the conformation of a pentablock copolymer that consists of randomly sulfonated polystyrene, an ionomeric block, bound to poly-ethylene-r-propylene end caped by poly-t-butylstyrene has been studied in dilute solutions using molecular dynamic simulations. Multi-block copolymers offer a means to tailor several properties into one molecule, taking advantage of their rich phase diagram together with unique properties of specific blocks. We varied the solvent quality for the different blocks and followed the changes in conformation. The spatial configuration of the pentablock as well as the dynamics of the polymer was studied. We find that, independent on the solvent, the higher the sulfonation level, the lower Rg . The static and dynamic structure factors were calculated and compared in an implicit poor solvent, water and a common solvent. These data are compared with results obtained from neutron scattering.

  20. Mechanically and structurally robust sulfonated block copolymer membranes for water purification applications

    Science.gov (United States)

    Yeo, J.; Kim, S. Y.; Kim, S.; Ryu, D. Y.; Kim, T.-H.; Park, M. J.

    2012-06-01

    The effective removal of ionic pollutants from contaminated water using negatively charged nanofiltration membranes is demonstrated. Block copolymers comprising polystyrene (PS) and partially hydrogenated polyisoprene (hPI) were synthesized by varying chain architectures. A one step procedure of cross-linking (hPI blocks) and sulfonation reactions (PS chains) was then carried out, which was revealed as an effective method to enhance mechanical integrity of membranes while hydrophilic sulfonated chains remain intact. In particular, the control of chain architecture allows us to create a synergetic effect on optimizing charge densities of the membrane, water permeability, and mechanical integrity under water purification conditions. The best performing membrane can almost completely (>99%) reject various divalent cations and also show NO3- rejection > 85% and Na+ rejection > 87%. Well defined nanostructures (tens of nanometers) as well as the periodically arranged water domains (a few nanometers) within hydrophilic phases of the hydrated membranes were confirmed by in situ neutron scattering experiments.