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Sample records for alkylbenzene sulfonate las

  1. 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)

  2. 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. PMID:25765258

  3. 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.

  4. 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. PMID:25999174

  5. 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

    2016-07-01

    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. PMID:27088975

  6. Anaerobic degradation of linear alkylbenzene sulfonate

    DEFF Research Database (Denmark)

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

    2003-01-01

    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 increa...... under thermophilic conditions was 37% with LAS as sole carbon source. Benzaldehyde was produced in the UASB reactor during LAS transformation....

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

    International Nuclear Information System (INIS)

    Highlights: • The marine shrimp Palaemonetes varians concentrates waterborne linear alkylbenzene sulfonate (LAS). • Size/weight plays a role in the LAS concentration in shrimp. • The LAS previously concentrated in the shrimp are rapidly depurated and weakly retained. • Shrimp’s target compartments for concentration of waterborne LAS are mainly located in the cephalothorax. - Abstract: Uptake and depuration kinetics of dissolved [14C]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

  8. 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. PMID:22053469

  9. 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.

  10. 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. PMID:26070080

  11. 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

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

    DEFF Research Database (Denmark)

    Gavala, Hariklia N.; Ahring, Birgitte Kiær

    2002-01-01

    it is important to investigate the effect of these xenobiotic compounds on an anaerobic environment. The inhibitory effect of Linear Alkylbenzene Sulfonates (LAS) on the acetogenic and methanogenic step of the anaerobic digestion process was studied. LAS inhibit both acetogenesis from propionate...... and methanogenesis from acetate and hydrogen and it is shown that the propionate-utilising bacteria are more sensitive to the presence of LAS than the acetoclastic methanogens. It has been proven that the inhibition intensity depends on the solids concentration and thus the term "biomass specific LAS concentration......" has been introduced in order to describe the phenomenon better. Conclusively, it is believed that the inhibitory effect of LAS is the main reason that anaerobic microbial enrichments on LAS have not been succeeded yet. Also, the inhibition caused by LAS on the acetogenic and methanogenic step...

  13. 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...... 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 mg 1(-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). EC50 values for a 50% inhibition of the transpiration of the trees were estimated to 374 mg 1(-1) (72 h) and 166 mg 1(-1) (192 h). Results from this experiment indicated that phytotoxic...

  14. 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...

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. 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.

  2. 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.

  3. 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.

  4. Reactive transport experiments of linear alkylbenzene sulfonate in laboratory soil columns

    OpenAIRE

    Boluda Botella, Nuria; Cases López, Vicente; León León, Victor Manuel; Gomis Yagües, Vicente; Prats Rico, Daniel

    2007-01-01

    Laboratory column experiments aids in the understanding of hydrogeochemistry dynamics of different linear alkylbenzene sulfonate homologues when they interact with different sand/soil proportions. Previously it was necessary to characterize the soil columns with a tracer. In this paper, the method to obtain breakthrough curves for the conductivity and chloride concentration of a tracer is verified, and also permits the calculation of transport parameters with an easy-to-use interface, ACUAINT...

  5. 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.

  6. 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.

  7. 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.

  8. Inhibition of biogas production by alkyl benzene sulfonates (LAS) in a screening test for anaerobic biodegradability.

    Science.gov (United States)

    Garcia, M Teresa; Campos, Encarna; Dalmau, Manel; Illán, Patricia; Sánchez-Leal, Joaquin

    2006-02-01

    The effect of the inoculum source on the digestion of linear alkylbenzene sulfonates (LAS) under anaerobic conditions has been investigated. The potential for primary and ultimate LAS biodegradation of anaerobic sludge samples obtained from wastewater treatment plants (WWTPs) of different geographical locations was studied applying a batch test system. It was found that only 4-22% of the LAS added to the batch anaerobic digesters was primarily transformed suggesting a poor primary degradation of the LAS molecule in anaerobic discontinuous systems. Regarding ultimate biodegradation, the addition of LAS to the batch anaerobic digesters caused a reduction on the extent of biogas production. Significant differences in the inhibition extent of the biogas production were observed (4-26%) depending on the sludge used as inoculum. Effect of the surfactant on the anaerobic microorganisms was correlated with its concentration in the aqueous phase. Sorption of LAS on anaerobic sludge affects its toxicity by depletion of the available fraction of the surfactant. LAS content on sludge was related to the total amount of calcium and magnesium extractable ions. The presence of divalent cations promote the association of LAS with anaerobic sludge reducing its bioavailability and the extent of its inhibitory effect on the biogas production. PMID:16453170

  9. 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.

  10. 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. The surfact......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...

  11. MBAS (Methylene Blue Active Substances) and LAS (Linear Alkylbenzene Sulphonates) in Mediterranean coastal aerosols: Sources and transport processes

    Science.gov (United States)

    Becagli, S.; Ghedini, C.; Peeters, S.; Rottiers, A.; Traversi, R.; Udisti, R.; Chiari, M.; Jalba, A.; Despiau, S.; Dayan, U.; Temara, A.

    2011-12-01

    Methylene Blue Active Substances (MBAS) and Linear Alkylbenzene Sulphonates (LAS) concentrations, together with organic carbon and ions were measured in atmospheric coastal aerosols in the NW Mediterranean Basin. Previous studies have suggested that the presence of surfactants in coastal aerosols may result in vegetation damage without specifically detecting or quantifying these surfactants. Coastal aerosols were collected at a remote site (Porquerolles Island-Var, France) and at a more anthropised site (San Rossore National Park-Tuscany, Italy). The chemical data were interpreted according to a comprehensive local meteorological analysis aiming to decipher the airborne source and transport processes of these classes of compounds. The LAS concentration (anthropogenic surfactants) was measured in the samples using LC-MS/MS, a specific analytical method. The values were compared with the MBAS concentration, determined by a non-specific analytical method. At Porquerolles, the MBAS concentration (103 ± 93 ng m -3) in the summer samples was significantly higher than in the winter samples. In contrast, LAS concentrations were rarely greater than in the blank filters. At San Rossore, the mean annual MBAS concentration (887 ± 473 ng m -3 in PM10) contributed about 10% to the total atmospheric particulate organic matter. LAS mean concentration in these same aerosol samples was 11.5 ± 10.5 ng m -3. A similar MBAS (529 ± 454 ng m -3) - LAS (7.1 ± 4.1 ng m -3 LAS) ratio of ˜75 was measured in the fine (PM2.5) aerosol fraction. No linear correlation was found between MBAS and LAS concentrations. At San Rossore site the variation of LAS concentrations was studied on a daily basis over a year. The LAS concentrations in the coarse fraction (PM10-2.5) were higher during strong sea storm conditions, characterized by strong air flow coming from the sea sector. These events, occurring with more intensity in winter, promoted the formation of primary marine aerosols containing LAS

  12. 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...

  13. 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...

  14. 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.

  15. 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.

  16. Properties of polypyrrole doped with alkylbenzene sulfonates

    DEFF Research Database (Denmark)

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

    2001-01-01

    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 o...

  17. 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)

    OpenAIRE

    Marina Freitas Stefanoni; Denis Moledo de Souza Abessa

    2011-01-01

    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 ...

  18. Method of producing alkylbenzene

    Energy Technology Data Exchange (ETDEWEB)

    Samokhvalov, A.I.; Golod, A.L.; Khadzhiyev, S.N.; Kirilin, Yu.A.; Nikitin, Yu.A.; Sumanov, V.T.

    1979-09-25

    An improved method of producing alkylbenzene (AB) by alkylation of isoparaffin hydrocarbons using olefin hydrocarbons in the presence of H/sub 2/SO/sub 4/ (I) by turbulent contact of (I) and a mixture of hydrocarbons at a reagent feed rate 1.0-8.0 m/sec for 0.1-1.5 seconds at a temperature from -2 to +120 degrees and pressure of approximately 48 atm is proposed. The parameters of the alkylation process are cited. The AB obtained features an octane number of 92.2 and contains 5.2 parts per million esters of I. The method makes it possible to obtain high quality AB and simplifies equipment and reduces process time.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. 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...

  5. 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

  6. Equilibrium partitioning theory to predict the sediment toxicity of the anionic surfactant C{sub 12}-2-LAS to Corophium volutator

    Energy Technology Data Exchange (ETDEWEB)

    Rico-Rico, Angeles [Institute for Risk Assessment Sciences, Utrecht University, Yalelaan 2, 3508 TD, Utrecht (Netherlands)], E-mail: a.ricorico@uu.nl; Temara, Ali [Procter and Gamble Company, Central Product Safety, Temselaan 100, 1853 Strombeek-Bever (Belgium); Hermens, Joop L.M. [Institute for Risk Assessment Sciences, Utrecht University, Yalelaan 2, 3508 TD, Utrecht (Netherlands)

    2009-02-15

    The study of the effect of the sorption of linear alkylbenzene sulfonates (LAS) on the bioavailability to marine benthic organisms is essential to refine the environmental risk assessment of these compounds. According to the equilibrium partitioning theory (EqP), the effect concentration in water-only exposure will be similar to the effect concentration in the sediment pore water. In this work, sorption and desorption experiments with two marine sediments were carried out using the compound C{sub 12}-2-LAS. The effect of the sediment sorption on the toxicity of benthic organisms was studied in water-only and in sediment bioassays with the marine mud shrimp Corophium volutator. In addition, three common spiking methods were tested for its application in the toxicity tests, as well as the stability of the surfactant during the water-only and sediment-water test duration. LC50 values obtained from water-only exposure showed a good correspondence with the pore water concentrations calculated from the sorption and desorption isotherms in the spiked sediments. - The toxicity of linear alkylbenzene sulfonate to Corophium volutator in marine sediments can be predicted from toxicity measured via water-only exposure.

  7. 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.

  8. Investigations of ultrafast dynamics in electronically excited alkylbenzenes

    Directory of Open Access Journals (Sweden)

    Maksyutenko P.

    2013-03-01

    Full Text Available We investigate ultrafast dynamics in electronically excited states of some typical alkylbenzenes by time-resolved two-colour four wave mixing and velocity map imaging as complementary methods. In this context an upgraded double-sided time-resolved velocity map imaging setup is also proposed.

  9. Exposure of the marine deposit feeder Hydrobia ulvae to sediment associated LAS

    Energy Technology Data Exchange (ETDEWEB)

    Mauffret, A., E-mail: aourell.mauffret@icman.csic.e [Marine Sciences Institute of Andalusia (CSIC), Puerto Real (Cadiz) (Spain); Rico-Rico, A. [Institute for Risk Assessment Sciences, Utrecht University (Netherlands); Temara, A. [The Procter and Gamble Company, Brussels (Belgium); Blasco, J. [Marine Sciences Institute of Andalusia (CSIC), Puerto Real (Cadiz) (Spain)

    2010-02-15

    Linear Alkylbenzene Sulfonates (LAS) effects (mortality, egestion rate, behaviour) on the marine deposit feeder Hydrobia ulvae were assessed in whole-sediment and water-only systems. The results were combined with a bioenergetic-based kinetic model of exposure pathways to account for the observed toxicity. The 10-d LC50 value based on the freely dissolved fraction was 9.3 times lower in spiked sediment (0.152 +- 0.001 (95% CI) mg/L) than in water-only (1.390 +- 0.020 (95% CI) mg/L). Consequently, the actual 10-d LC50 value (208 mg/kg) was overestimated by the Equilibrium Partitioning calculation (1629 mg/kg). This suggests that the sediment associated LAS fraction was bioavailable to the snails. It could also be due to modifications in physiological parameters in absence of sediment, the organism natural substrate. - Lethality of the marine gastropod deposit feeder Hydrobia ulvae exposed to LAS in water-only system was inappropriate to predict LAS toxicity in sediment system.

  10. Effect of sediment properties on the sorption of C{sub 12}-2-LAS in marine and estuarine sediments

    Energy Technology Data Exchange (ETDEWEB)

    Rico-Rico, Angeles [Institute for Risk Assessment Sciences, Utrecht University, Yalelaan 2, 3508 TD Utrecht (Netherlands)], E-mail: a.ricorico@uu.nl; Temara, Ali [Procter and Gamble Company, Central Product Safety, Temselaan 100, 1853 Strombeek-Bever (Belgium); Behrends, Thilo [Department of Earth Sciences-Geochemistry, Faculty of Geosciences, Utrecht University, 3508 TA Utrecht (Netherlands); Hermens, Joop L.M. [Institute for Risk Assessment Sciences, Utrecht University, Yalelaan 2, 3508 TD Utrecht (Netherlands)

    2009-02-15

    Linear alkylbenzene sulfonates (LAS) are anionic high production volume surfactants used in the manufacture of cleaning products. Here, we have studied the effect of the characteristics of marine and estuarine sediments on the sorption of LAS. Sorption experiments were performed with single sediment materials (pure clays and sea sand), with sediments treated to reduce their organic carbon content, and with field marine and estuarine sediments. C{sub 12}-2-LAS was used as a model compound. Sorption to the clays montmorillonite and kaolinite resulted in non-linear isotherms very similar for both clays. When reducing the organic content, sorption coefficients decreased proportionally to the fraction removed in fine grain sediments but this was not the case for the sandy sediment. The correlation of the sediment characteristics with the sorption coefficients at different surfactant concentrations showed that at concentrations below 10 {mu}g C{sub 12}-2-LAS/L, the clay content correlated better with sorption, while the organic fraction became more significant at higher concentrations. - Sorption of C{sub 12}-2-LAS to marine sediments mainly depends on both clay and organic carbon content. The importance of each parameter varies with the surfactant concentration.

  11. 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.

  12. Rayleigh scattering and depolarization ratio in linear alkylbenzene

    CERN Document Server

    Liu, Qian; Huang, Wenqian; Zhang, Yuning; Wu, Wenjie; Luo, Wentai; Yu, Miao; Zheng, Yangheng; Zhou, Li; Cao, Jun; Wang, Yifang

    2015-01-01

    Linear alkylbenzene (LAB) is adopted to be the organic solvent for the Jiangmen Underground Neutrino Observatory (JUNO) liquid scintillator detectors due to the ultra-transparency. However the current Rayleigh scattering length calculation disagrees with the measurement. The present paper for the first time reports the Rayleigh scattering of LAB being anisotropic and the depolarization ratio being 0.31+-0.01(stat.)+-0.01(sys.). We proposed an indirectly method for Rayleigh scattering measurement with Einstein-Smoluchowski-Cabannes formula, and the Rayleigh scattering length of LAB is determined to be 28.2+-1.0 m at 430 nm.

  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. Rayleigh scattering and depolarization ratio in linear alkylbenzene

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qian, E-mail: liuqian@ucas.ac.cn [University of Chinese Academy of Sciences, 100049 Beijing (China); Zhou, Xiang [Hubei Nuclear Solid Physics Key Laboratory, Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Huang, Wenqian [University of Chinese Academy of Sciences, 100049 Beijing (China); Hubei Nuclear Solid Physics Key Laboratory, Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Zhang, Yuning [University of Chinese Academy of Sciences, 100049 Beijing (China); Wu, Wenjie [Hubei Nuclear Solid Physics Key Laboratory, Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Luo, Wentai [University of Chinese Academy of Sciences, 100049 Beijing (China); Hubei Nuclear Solid Physics Key Laboratory, Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Yu, Miao [Hubei Nuclear Solid Physics Key Laboratory, Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Zheng, Yangheng [University of Chinese Academy of Sciences, 100049 Beijing (China); Zhou, Li; Cao, Jun; Wang, Yifang [Institute of High Energy Physics, Chinese Academy of Science, 100049 Beijing (China)

    2015-09-21

    It is planned to use linear alkylbenzene (LAB) as the organic solvent for the Jiangmen Underground Neutrino Observatory (JUNO) liquid scintillator detectors, due to its ultra-transparency. However, the current Rayleigh scattering length calculation for LAB disagrees with the experimental measurement. This paper reports for the first time that the Rayleigh scattering of LAB is anisotropic, with a depolarization ratio of 0.31±0.01(stat.)±0.01(sys.). We use an indirect method for Rayleigh scattering measurement with the Einstein–Smoluchowski–Cabannes formula, and the Rayleigh scattering length of LAB is determined to be 28.2±1.0 m at 430 nm.

  15. Rayleigh scattering and depolarization ratio in linear alkylbenzene

    International Nuclear Information System (INIS)

    It is planned to use linear alkylbenzene (LAB) as the organic solvent for the Jiangmen Underground Neutrino Observatory (JUNO) liquid scintillator detectors, due to its ultra-transparency. However, the current Rayleigh scattering length calculation for LAB disagrees with the experimental measurement. This paper reports for the first time that the Rayleigh scattering of LAB is anisotropic, with a depolarization ratio of 0.31±0.01(stat.)±0.01(sys.). We use an indirect method for Rayleigh scattering measurement with the Einstein–Smoluchowski–Cabannes formula, and the Rayleigh scattering length of LAB is determined to be 28.2±1.0 m at 430 nm

  16. 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.

  17. 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.)

  18. 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.

  19. Origin of long-chain alkylcyclohexanes and alkylbenzenes in a coal-bed wax

    Science.gov (United States)

    Dong, Ji-Zhou; Vorkink, William P.; Lee, Milton L.

    1993-02-01

    A coal-bed wax was fractionated and analyzed using capillary column GC and combined GC/MS. It was found that the major components in the wax were n-alkanes (55.6%), cyclic/branched alkanes (26.0%), and several homologous series of alkylbenzenes (5.7%). All alkylbenzene isomers (except 6- n-alkyl- m-xylene) were positively identified by comparison with the retention times and mass spectra of newly synthesized authentic standards. 5- n-Alkyl- m-xylene, 2- n-alkyl- p-xylene, 4- n-alkyl- m-xylene, 4- n-alkyl- o-xylene, 2- n-alkyl- m-xylene, and 3- n-alkyl- o-xylene were identified for the first time from geological sources. All of these long-chain alkyl compounds (e.g., n-alkylcyclohexanes, n-alkylbenzenes, n-alkyl- o-toluenes, n-alkyl- p-toluenes, and 5- n-alkyl- m-xylenes) have similar total carbon number distributions and maxima with a slight even over odd carbon number preference between C 28-C 30. Moreover, the carbon number distributions of these compounds resembled those of the n-alkanes found in the same wax with slight odd over even carbon preference between C 27-C 21. This indicates that the alkylcyclohexanes and alkylbenzenes may have the same fatty acid precursors as the n-alkanes. The alkylcyclohexanes and alkylbenzenes could have been formed by direct cyclization and aromatization, while the n-alkanes could have been formed by decarboxylation of the straight chain fatty acids. This explanation is further supported by the identification of homologous series of tetramethyl- n-alkylbenzenes and pentamethyl- n-alkylbenzenes with relatively high abundances at C 15, C 16, and C 18, and a fatty acid distribution with maxima at C 16 and C 18. Based on these findings, mechanisms for the conversion of fatty acids or alcohols to alkylcyclohexanes and alkylbenzenes are proposed.

  20. Efficient photolytic C-H bond functionalization of alkylbenzene with hypervalent iodine(iii) reagent.

    Science.gov (United States)

    Sakamoto, Ryu; Inada, Tsubasa; Selvakumar, Sermadurai; Moteki, Shin A; Maruoka, Keiji

    2016-03-01

    A practical approach to radical C-H bond functionalization by the photolysis of a hypervalent iodine(iii) reagent is presented. The photolysis of [bis(trifluoroacetoxy)iodo]benzene (PIFA) leads to the generation of trifluoroacetoxy radicals, which allows the smooth transformation of various alkylbenzenes to the corresponding benzyl ester compounds under mild reaction conditions. PMID:26686276

  1. Increasing maturity of kerogen type II reflected by alkylbenzene distribution from pyrolysis-gas chromatography-mass spectrometry

    Science.gov (United States)

    Lis, G.P.; Mastalerz, Maria; Schimmelmann, A.

    2008-01-01

    A series of Late Devonian to Early Mississippian type II kerogens with vitrinite reflectance values Ro 0.29-2.41% were analyzed using py-GC-MS. In addition, a low maturity kerogen with Ro 0.44% was separated into fractions via density gradient centrifugation, followed by py-GC-MS of the alginite and amorphinite maceral concentrates. Alkylbenzenes and n-alk-1-ene/n-alkane doublets represented the main compound classes identified in all pyrolysates. The pyrolysate from alginite featured 1,2,4-trimethylbenzene and toluene as the two most prominent alkylbenzenes. In contrast, alkylbenzenes in pyrolysates from amorphinite and low maturity bulk kerogens with Ro 0.29-0.63% were dominated by 1,2,3,4-tetramethylbenzene. With increasing thermal maturity, pyrolysates were increasingly dominated by (i) alkylbenzenes with fewer methyl groups, namely by tri- and dimethylbenzenes at medium maturity (Ro 0.69-1.19%), and (ii) by toluene at higher maturity (Ro 1.30-2.41%). With increasing maturity of kerogen type II, the decreasing abundance of highly methyl-substituted alkylbenzenes and the parallel increase in less methyl-substituted alkylbenzenes in flash pyrolysates suggest that demethylation is an important chemical process in the thermal maturation of kerogen type II. ?? 2008 Elsevier Ltd. All rights reserved.

  2. 21 CFR 573.600 - Lignin sulfonates.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Lignin sulfonates. 573.600 Section 573.600 Food... Additive Listing § 573.600 Lignin sulfonates. Lignin sulfonates may be safely used in animal feeds in... feeds, as liquid lignin sulfonate, in an amount not to exceed 11 percent of the molasses. (4) As...

  3. 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.

  4. 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...

  5. Preparation and characterization of proton exchange poly (ether sulfone)s membranes grafted propane sulfonic acid on pendant phenyl groups

    International Nuclear Information System (INIS)

    Poly(ether sulfone)s containing hexaphenyl (PHP) was prepared by 1,2-bis(4-hydroxyphenyl)-3,4,5,6-tetraphenylbenzene, 4,4-hydroxyphenylsulfone, and 4,4-fluorophenylsulfone, followed bromination on phenyl groups to produce brominated PHP (Br-PHP). Grafted sulfonated poly(ether sulfone)s containing hexaphenyl (GSPHP) were prepared from Br-PHP and 3-bromopropane sulfonic acid with potassium salt and copper powder. The salt form was converted to free acid using 1 M sulfuric acid solution. All these membranes were cast from dimethylacetamide (DMAc). The structural properties of the synthesized polymers were investigated by 1H-NMR spectroscopy. The membranes were studied with regard to ion exchange capacity (IEC), water uptake, Fenton test, and proton conductivity. These grafted polymer membranes were compared with normal sulfonated poly(ether sulfone)s and Nafion

  6. 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

  7. 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)

  8. 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.

  9. 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)

  10. 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....

  11. 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.

  12. 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.

  13. Alkalized sulfonates (PEP additives); Ueberbasische Sulfonate (PEP-Additive)

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, Joachim [WISURA Mineraloelwerk Goldgrabe und Scheft GmbH und Co., Bremen (Germany)

    2010-05-15

    There are only few additives about which in the last 25 - to 30 were reported as a possible additive group regarding replacement of chlorinated paraffin's. Besides, it concerns around alkalized sulfonic acids which are neutralized with sodium or calcium-hydroxide and contain, in addition, the corresponding carbonate in large quantities. This class of additives should act passively in metalworking under extreme pressure (Passive Extreme Pressure additive). Observations from the field often provide a different picture. The following article offers a literature overview to the reaction behavior and introduces newer lab results. A new model of the (re)action of these additives will be introduced. (orig.)

  14. 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.

  15. 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.

  16. Sulfonates and Organotrophic Sulfite Metabolism

    OpenAIRE

    Cook, Alasdair M.; Theo H. M. Smits; Denger, Karin

    2007-01-01

    One is used to considering sulfite oxidation as part of a lithotrophic process (e.g. SorAB or Sox system), much of which involves neutral or ionic inorganic sulfur species on the outer surface of the cytoplasmic membrane. In contrast, the processes referred to in this chapter involve organic compounds, which (1) include a highly stable sulfonate substituent (C−SO3−), (2) are involved in the organotrophic growth of the organism and (3) much of whose metabolism takes place in the cytoplasm. Man...

  17. 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.

  18. Solubilization of n-alkylbenzenes into gemini surfactant micelles in aqueous medium.

    Science.gov (United States)

    Nakahara, Hiromichi; Kojima, Yui; Moroi, Yoshikiyo; Shibata, Osamu

    2014-05-27

    Solubilization of benzene, toluene, ethylbenzene, n-propylbenzene, n-butylbenzene, and n-pentylbenzene into micelles of decanediyl-1-10-bis(dimethyltetradecylammonium bromide) (14-10-14,2Br(-)) has been investigated in the temperature range from 288.2 to 308.2 K. The equilibrium concentrations of all the solubilizates are determined spectrophotometrically. The concentration of the solubilizates remains constant below the critical micelle concentration (cmc) and increases linearly with an increase in 14-10-14,2Br(-) concentration above the cmc. Compared to the mother micelle, the solubilized micelles indicate much larger hydrodynamic diameters, which are determined by dynamic light scattering. Therefore, the Gibbs energy change for the solubilization of n-alkylbenzenes has been evaluated by the partitioning of the solubilizates between the aqueous and micellar phases. Furthermore, the enthalpy and entropy changes for the solubilization could be calculated from temperature dependence of the Gibbs energy change. From the thermodynamic parameters, it is found that the solubilization for the present system is entropy-driven and that the location of the solubilizates moves into the inner core of the micelle with an elongation of their alkyl chains. The movement on the location is also supported by the results of absorption spectra, Fourier transform infrared (FTIR) spectra, and two-dimensional nuclear Overhauser effect spectroscopy (2-D NOESY). PMID:24802668

  19. 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.

  20. 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.

  1. Evaluation of the asphaltenes macromolecules stabilization by alkylbenzenes compounds; Avaliacao da estabilizacao de macromoleculas asfaltenicas por compostos alquilbenzenicos

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, G.E.; Mansur, C.R.E.; Lucas, E.F. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Macromoleculas]. E-mail: elucas@ima.ufrj.br; geiza@ima.ufrj.br; Gonzalez, G. [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas]. E-mail: gaspar@cenpes.petrobras.com.br

    2003-07-01

    The asphaltene deposition is a problem that affects oil production, transportation and storage. Some researches about asphaltene stabilization have been made in order to avoid its flocculation and deposition. In this work, the performance of four alkylbenzene compounds as asphaltene stabilizer was evaluated. The additive were tested in two different concentrations: 5000 and 10000 mg/L. Cardanol, polycardanol, polystyrene and polystyrene sulfonade were used as additive. The study was carried out by asphaltene precipitation in a solvent mixture (toluene and heptane), since that the asphaltene solubility in these solvents are different. The best results were obtained by using cardanol, at 5000 mg/L. (author)

  2. 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.

  3. 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.

  4. 高碱值磺酸钙制备工艺开发%Research on the preparation of overbasd calcium sulfonate

    Institute of Scientific and Technical Information of China (English)

    尚小清; 刘永彪

    2011-01-01

    The preparation of overbased calcium sulfonate was researched with F heavy alkylbenzene as material. The effects of various technological conditions on the solid content,filtration velocity,yield and quality of product were investigated. By changing the technological condition and adjusting the amount of solvent and promoter, the optimization experiments were conducted to research the preparation of overbased calcium sulfonate process of new technology, and the two-step process , the original step process, the improved one step process,and the new process technology were compared. Results indicated that the new process has short cycle and can be carried out in the low working strength ; the overbased calcium sulfonate production is not only up to standard in quality but also produced in a stable way,the yield is 75. 5 %.%对以F重烷基苯为原料的高碱值磺酸钙制备工艺进行研究,考察了各种工艺条件对产品的同体含量、过滤速度、产品收率和产品质世的影响,通过改变工艺条件及调整溶剂和促进剂用量进行优化组合实验,研究高碱值磺酸钙制备新工艺,并对比两步法、原一步法、改良一步法、新工艺等4种工艺进行实验.实验结果表明,新工艺的生产周期短,操作强度低,生产的高碱值磺酸钙产品质量合格且稳定,收率达到75.5%.

  5. 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

  6. 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.

  7. Deactivation of sulfonated hydrothermal carbons in the presence of alcohols: Evidences for sulfonic esters formation

    OpenAIRE

    Fraile, José M.; García Bordejé, E.; Roldán, Laura

    2012-01-01

    Sulfonated hydrothermal carbons present high activity for esterification of palmitic acid with alcohols. However, the catalyst is significantly deactivated upon recovery. Leaching of sulfonated species does not account for this deactivation, which is observed even by pretreatment only with the alcohol under reflux. Solid state NMR shows the presence of chemically bound alkyl groups coming from the alcohol, clearly different from strongly physisorbed species obtained by pretreatment at room te...

  8. 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.

  9. 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.

  10. Neuroendocrine effects of perfluorooctane sulfonate in rats.

    OpenAIRE

    Austin, Maureen E; Kasturi, Badrinarayanan S.; Barber, Matthew; Kannan, Kurunthachalam; MohanKumar, Puliyur S.; MohanKumar, Sheba M.J.

    2003-01-01

    Perfluorooctane sulfonate (PFOS) is a degradation product of sulfonyl-based fluorochemicals that are used extensively in industrial and household applications. Humans and wildlife are exposed to this class of compounds from several sources. Toxicity tests in rodents have raised concerns about potential developmental, reproductive, and systemic effects of PFOS. However, the effect of PFOS on the neuroendocrine system has not been investigated thus far. In this study, adult female rats were inj...

  11. 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.

  12. 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).

  13. Methane sulfonic acid in the marine atmosphere

    OpenAIRE

    E. S. Saltzman; Savoie, D. L.; Zika, R. G; J. M. Prospero

    1983-01-01

    Methane sulfonic acid (MSA) is an oxidation product of the reaction of OH radical with dimethyl sulfide and, hence, should be an important constituent of marine air. MSA concentrations in marine aerosols ranged from 0.009 to 0.075 μg/m3 in samples from the Pacific and Indian oceans and Miami, Florida. In the samples from remote areas (Pacific and Indian oceans), MSA levels averaged 6.7% (S = 1.9) of the non-sea-salt (nss) SO4 =. In the Miami area, ratios were occasionally lower be...

  14. Experience with chemicals regulation - Lessons from the Danish LAS case

    DEFF Research Database (Denmark)

    Lauridsen, Pia Vestergaard; Røpke, Inge

    2006-01-01

    understanding of how chemicals regulation is being shaped through social and political processes, and which lessons can be drawn regarding the effectiveness of different regulatory measures. We outline briefly the history of the chemicals regulation as a background for the detailed discussion of the case study......Chemicals regulation is under pressure for change, and lessons from former experience are important to inform the process. This paper is based on a case study of the Danish measures towards regulating a specific substance, Linear Alkylbenzene Sulphonate (LAS), and the case is used to deepen the....... Finally, we present a few tentative proposals for future changes of the chemicals regulation and conclude with relating the case to the ecological modernization discourse....

  15. Depositional history of sedimentary linear alkylbenzenes (LABs) in a large South American industrial coastal area (Santos Estuary, Southeastern Brazil)

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Cesar C., E-mail: ccmart@ufpr.b [Centro de Estudos do Mar da Universidade Federal do Parana, Caixa Postal 50.002, 83255-000, Pontal do Sul, Pontal do Parana, PR (Brazil); Instituto Oceanografico da Universidade de Sao Paulo, Praca do Oceanografico, 191, 05508-900, Sao Paulo - SP (Brazil); Bicego, Marcia C.; Mahiques, Michel M.; Figueira, Rubens C.L.; Tessler, Moyses G.; Montone, Rosalinda C. [Instituto Oceanografico da Universidade de Sao Paulo, Praca do Oceanografico, 191, 05508-900, Sao Paulo - SP (Brazil)

    2010-11-15

    This paper reports the reconstruction of the contamination history of a large South American industrial coastal area (Santos Estuary, Brazil) using linear alkylbenzenes (LABs). Three sediment cores were dated by {sup 137}Cs. Concentrations in surficial layers were comparable to the midrange concentrations reported for coastal sediments worldwide. LAB concentrations increased towards the surface, indicating increased waste discharges into the estuary in recent decades. The highest concentration values occurred in the early 1970s, a time of intense industrial activity and marked population growth. The decreased LAB concentration, in the late 1970s was assumed to be the result of the world oil crisis. Treatment of industrial effluents, which began in 1984, was represented by decreased LAB levels. Microbial degradation of LABs may be more intense in the industrial area sediments. The results show that industrial and domestic waste discharges are a historical problem in the area. - The contamination history of a large South American industrial coastal area indicated by molecular indicator of sewage input.

  16. 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.

  17. Electrical conductivity of sulfonated poly(ether ether ketone) based composite membranes containing sulfonated polyhedral oligosilsesquioxane

    Science.gov (United States)

    Celso, Fabricio; Mikhailenko, Serguei D.; Rodrigues, Marco A. S.; Mauler, Raquel S.; Kaliaguine, Serge

    2016-02-01

    Composite proton exchange membranes (PEMs) intended for fuel cell applications were prepared by embedding of various amounts of dispersed tri-sulfonic acid ethyl POSS (S-Et-POSS) and tri-sulfonic acid butyl POSS (S-Bu-POSS) in thin films of sulfonated poly ether-ether ketone. The electrical properties of the PEMs were studied by Impedance spectroscopy and it was found that their conductivity σ changes with the filler content following a curve with a maximum. The water uptake of these PEMs showed the same dependence. The investigation of initial isolated S-POSS substances revealed the properties of typical electrolytes, which however in both cases possessed low conductivities of 1. 17 × 10-5 S cm-1 (S-Et-POSS) and 3.52 × 10-5 S cm-1 (S-Bu-POSS). At the same time, the insoluble in water S-POSS was found forming highly conductive interface layer when wetted with liquid water and hence producing a strong positive impact on the conductivity of the composite PEM. Electrical properties of the composites were analysed within the frameworks of effective medium theory and bounding models, allowing to evaluate analytically the range of possible conductivity values. It was found that these approaches produced quite good approximation of the experimental data and constituted a fair basis for interpretation of the observed relationship.

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

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jinyang; Zhong, Haimin; Qiu, Wenda; Chen, Liuping, E-mail: cesclp@mail.sysu.edu.cn [KLGHEI of Environment and Energy Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Feng, Huajie [School of Chemistry and Chemical Engineering, Hainan Normal University, Haikou 571158 (China)

    2014-03-14

    The binary infinite dilute diffusion coefficients, D{sub 12}{sup ∞}, of some alkylbenzenes (Ph-C{sub n}, from Ph-H to Ph-C{sub 12}) from 313 K to 333 K at 15 MPa in supercritical carbon dioxide (scCO{sub 2}) 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{sub n}/CO{sub 2} fluids are further investigated by calculating radial distribution functions and coordination numbers. It qualitatively convinces that the first solvation shell of Ph-C{sub n} in scCO{sub 2} is significantly influenced by the structure of Ph-C{sub 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{sub n} in scCO{sub 2}. 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{sub n} is the result of internal rotation of C-C single bond (σ{sub 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{sub 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{sub n} (n ≥ 4) in scCO{sub 2} are different.

  19. 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.

  20. 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.

  1. 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.

  2. Synthesis and Characterization of Poly(arylene ether sulfone)s for Reverse Osmosis Water Purification and Gas Separation Membranes

    OpenAIRE

    Sundell, Benjamin James

    2014-01-01

    Crosslinking is an effective technique for increasing the salt rejection of water purification membranes and the selectivity of gas separation membranes. An abundance of monomers, telechelic oligomers, and novel polymers were synthesized for use as separation membranes. These materials were often imbued with crosslinking functionalities to increase their performance during testing at the University of Texas-Austin. Crosslinking of sulfonated poly(arylene ether sulfone) oligomers was stud...

  3. 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.

  4. Synthesis and Characterization of trans-1,4-Cyclohexylene Ring Containing Poly(arylene ether sulfone)s

    OpenAIRE

    ZHANG Bin

    2012-01-01

    Poly(arylene ether sulfone)s (PAES) are important commercial polymers and have been extensively studied due to their excellent thermal and mechanical properties. However, some applications are still limited when good solvent resistance and low thermal expansion coefficient are required. There has been a continuous interest in developing new PAES based on new monomers or polymer modifications to obtain new properties or to enhance existing properties. In this dissertation, the synthesis, chara...

  5. Neuroendocrine effects of perfluorooctane sulfonate in rats.

    Science.gov (United States)

    Austin, Maureen E; Kasturi, Badrinarayanan S; Barber, Matthew; Kannan, Kurunthachalam; MohanKumar, Puliyur S; MohanKumar, Sheba M J

    2003-09-01

    Perfluorooctane sulfonate (PFOS) is a degradation product of sulfonyl-based fluorochemicals that are used extensively in industrial and household applications. Humans and wildlife are exposed to this class of compounds from several sources. Toxicity tests in rodents have raised concerns about potential developmental, reproductive, and systemic effects of PFOS. However, the effect of PFOS on the neuroendocrine system has not been investigated thus far. In this study, adult female rats were injected intraperitoneally with 0, 1, or 10 mg PFOS/kg body weight (BW) for 2 weeks. Food and water intake, BW, and estrous cycles were monitored daily. At the end of treatment, PFOS levels in tissues were measured by high-performance liquid chromatography (HPLC) interfaced with electrospray mass spectrometry. Changes in brain monoamines were measured by HPLC with electrochemical detection, and serum corticosterone and leptin were monitored using radioimmunoassay. Treatment with PFOS produced a dose-dependent accumulation of this chemical in various body tissues, including the brain. PFOS exposure decreased food intake and BW in a dose-dependent manner. Treatment with PFOS affected estrous cyclicity and increased serum corticosterone levels while decreasing serum leptin concentrations. PFOS treatment also increased norepinephrine concentrations in the paraventricular nucleus of the hypothalamus. These results indicate that exposure to PFOS can affect the neuroendocrine system in rats. PMID:12948888

  6. 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

  7. 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.

  8. Synthesis, Characterization and Adsorption Studies of Sulfonated Poly(Styrene)

    International Nuclear Information System (INIS)

    Poly(styrene) was synthesized by suspension polymerization of styrene. Molar mass of poly(styrene) was determined by viscosity method. Sulfonated poly(styrene) was synthesized by direct sulfonation of poly(styrene) at 40 degree C. These products were identified by using IR spectroscopic technique. Cation exchange properties of sulfonated poly(styrene) have been determined for some metal ions such as Ni/sup 2+/, Zn/sup 2+/, Cu/sup 2+/ and Ca/sup 2+/. The distribution co-efficient and apparent adsorption capacities show that selectivity order of the metals as follow: Ni/sup 2+/ > Zn/sup 2+/ > Cu/sup 2+/ > Ca/sup 2+/. It was found that by increasing the pH of solution, the distribution Co-efficients (Kd) value also increased. (author)

  9. Hexaaquamagnesium(II bis(d-camphor-10-sulfonate

    Directory of Open Access Journals (Sweden)

    Dejan Jeremić

    2008-07-01

    Full Text Available The structure of the title complex, [Mg(H2O6](C10H15O4S2, consists of regular octahedral [Mg(H2O6]2+ cations and d-camphor-10-sulfonate anions. A three-dimensional supramolecular architecture is formed via hydrogen-bond interactions [O—H...O = 2.723 (2–2.833 (2 Å] to give alternating layers of [Mg(H2O6]2+ cations and d-camphor-10-sulfonate anions. The title compound is isomorphous with the zinc, copper, cadmium and nickel analogues.

  10. On the electronic transport mechanism in thin films of some new poly(azomethine sulfone)s

    International Nuclear Information System (INIS)

    The studied polymers, poly(azomethine sulfone)s, were prepared by the reaction of bis(4-chlorophenyl)sulfone with a mixture of bisphenols: 2,2-bis(p-hydroxyphenyl)propane (bisphenol A) and 4,4'-bis(4-hydroxybenzylideneiminophenoxy)biphenyl in various molar ratios. The temperature dependences of the electrical conductivity and Seebeck coefficient of polymers were investigated using thin-film samples deposited from chloroform solutions (spin coating method) onto glass substrates. It was found that the respective polymers show typical semiconducting properties. Some correlations between these properties and the chemical structures of the polymers were established. The mechanism of electronic transport in the films studied is discussed. The study of optical absorption (in spectral range, 300-1400 nm) evidenced direct bandgaps ranged between 1.30 and 1.80 eV

  11. On the electronic transport mechanism in thin films of some new poly(azomethine sulfone)s

    Energy Technology Data Exchange (ETDEWEB)

    Rusu, G.I. [Faculty of Physics, ' Al.I. Cuza' University, 11 Carol I Bldv, RO-700506, Iasi (Romania)]. E-mail: girusu@uaic.ro; Airinei, A. [P. Poni Institute of Macromolecular Chemistry, Aleea Grigore Ghica Voda, 41 A, RO-700487, Iasi (Romania); Rusu, M. [Faculty of Physics, ' Al.I. Cuza' University, 11 Carol I Bldv, RO-700506, Iasi (Romania); Prepelita, P. [Faculty of Physics, ' Al.I. Cuza' University, 11 Carol I Bldv, RO-700506, Iasi (Romania); Marin, L. [P. Poni Institute of Macromolecular Chemistry, Aleea Grigore Ghica Voda, 41 A, RO-700487, Iasi (Romania); Cozan, V. [P. Poni Institute of Macromolecular Chemistry, Aleea Grigore Ghica Voda, 41 A, RO-700487, Iasi (Romania); Rusu, I.I. [University of Bacau, 157 Marasesti Str., RO-600115 Bacau (Romania)

    2007-01-15

    The studied polymers, poly(azomethine sulfone)s, were prepared by the reaction of bis(4-chlorophenyl)sulfone with a mixture of bisphenols: 2,2-bis(p-hydroxyphenyl)propane (bisphenol A) and 4,4'-bis(4-hydroxybenzylideneiminophenoxy)biphenyl in various molar ratios. The temperature dependences of the electrical conductivity and Seebeck coefficient of polymers were investigated using thin-film samples deposited from chloroform solutions (spin coating method) onto glass substrates. It was found that the respective polymers show typical semiconducting properties. Some correlations between these properties and the chemical structures of the polymers were established. The mechanism of electronic transport in the films studied is discussed. The study of optical absorption (in spectral range, 300-1400 nm) evidenced direct bandgaps ranged between 1.30 and 1.80 eV.

  12. 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)

  13. 40 CFR 721.9595 - Alkyl benzene sulfonic acids and alkyl sulfates, amine salts (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkyl benzene sulfonic acids and alkyl... Significant New Uses for Specific Chemical Substances § 721.9595 Alkyl benzene sulfonic acids and alkyl...) The chemical substances identified generically as alkyl benzene sulfonic acids and alkyl...

  14. 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...

  15. 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...

  16. 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...

  17. 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.

  18. Toxicokinetics of perfluorooctane sulfonate in rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Rainbow trout (Oncorhynchus mykiss) confined to respirometer-metabolism chambers were dosed with perfluorooctane sulfonate (PFOS) by intra-arterial injection and sampled to obtain concentration time-course data for plasma, and either urine or expired water. The data were then an...

  19. 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.

  20. 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

  1. 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

  2. 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).

  3. las telecomunicaciones

    Directory of Open Access Journals (Sweden)

    Veneta Andonova

    2006-01-01

    Full Text Available En este artículo se estudian las interacciones entre tres tecnologías de comunicación, telefonía fija, móvil e Internet, modelizando los efectos de red y controlando por el impacto del ingreso per capita en el país y el nivel de precios de la tecnología, dos variables clave en el proceso de difusión de tecnologías de información. Los resultados de las estimaciones, usando una base de datos de 195 países, reflejan que (1 Internet y la telefonía móvil son totalmente complementarias; (2 la telefonía fija ayuda la difusión de la móvil mientras que la móvil canibaliza la fija; (3 la telefonía fija favorece la difusión de Internet mientras que el desarrollo de Internet no tiene ningún efecto significativo sobre la difusión de la telefonía fija. Estos resultados pueden ayudar en construir escenarios más sólidos y predecir el impacto de Voice Over Internet Protocol (VOIP en la industria de telecomunicaciones.

  4. 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)

  5. Hypernatremia in a patient treated with sodium polystyrene sulfonate

    Directory of Open Access Journals (Sweden)

    Manish Nepal

    2010-11-01

    Full Text Available Manish Nepal, Ion Dan Bucaloiu, Evan R NorfolkGeisinger Medical Center, Department of Nephrology, Danville, PA, USAAbstract: Severe hyperkalemia requires urgent medical attention and correction in order to prevent arrhythmic complications. Sodium polystyrene sulfonate (SPS is a cation exchange resin commonly used in the management of hyperkalemia. A recent review raised concerns regarding its effectiveness and potential adverse effects. Hypernatremia in adults in the setting of sodium polystyrene sulfonate therapy has not been described in the literature. We report the case of a woman who developed hypernatremia in the setting of excessive SPS administration and hope to increase awareness among clinicians regarding this potential side effect of SPS therapy.Keywords: SPS, hyperkalemia 

  6. 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.

  7. Toxicity of perfluorononanoic acid and perfluorooctane sulfonate to Daphnia magna

    OpenAIRE

    Lu, Guang-hua; Jian-chao LIU; Sun, Li-Sha; 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-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 rep...

  8. Hypernatremia in a patient treated with sodium polystyrene sulfonate

    OpenAIRE

    Nepal, M

    2010-01-01

    Manish Nepal, Ion Dan Bucaloiu, Evan R NorfolkGeisinger Medical Center, Department of Nephrology, Danville, PA, USAAbstract: Severe hyperkalemia requires urgent medical attention and correction in order to prevent arrhythmic complications. Sodium polystyrene sulfonate (SPS) is a cation exchange resin commonly used in the management of hyperkalemia. A recent review raised concerns regarding its effectiveness and potential adverse effects. Hypernatremia in adults in the setting of sodium polyst...

  9. 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...... to various degrees. Series of grafting densities and graft lengths are prepared, and membranes are solvent cast from DMSO. The membrane properties in aqueous environments are evaluated from their water swelling behavior, and their thermal properties and stability are investigated by thermogravimetric...

  10. Proton conductivity enhancement in oriented, sulfonated polyimide thin films

    OpenAIRE

    Krishnan, Karthik; Iwatsuki, Hiroko; Hara, Mitsuo; Nagano, Shusaku; Nagao, Yuki

    2014-01-01

    Studies of proton transport in confined thin polymer electrolytes are essential for providing additional information regarding the structure-property relationships of such materials. Using a combination of proton transport measurements and structural characterization, we explored the effect of proton conductivity in sulfonated polyimide (SPI) under both bulk and nanostructured thin film systems. SPI film confined to a thickness of approximately 530 nm shows significant proton conductivity enh...

  11. 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.

  12. 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.

  13. Composite plasma polymerized sulfonated polystyrene membrane for PEMFC

    International Nuclear Information System (INIS)

    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−1. • Power density of fuel cell with styrene/MMS membrane is 0.5 W cm−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−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−2 and current density of 0.62 A cm−2 at 0.6 V

  14. 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

  15. 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 Acartia....... The increased sensitivity under in situ conditions was probably promoted by the suboptimal growth conditions, e.g. no saturated food concentration or inadequate nutritive values of the food. The amount of food expressed as chlorophyll concentration was low (around 2 microg chl. a l(-1)) but was not affected...

  16. Effect of additives on the performance and morphology of sulfonated copoly (phthalazinone biphenyl ether sulfone) composite nanofiltration membranes☆

    Science.gov (United States)

    Guan, Shanshan; Zhang, Shouhai; Liu, Peng; Zhang, Guozhen; Jian, Xigao

    2014-03-01

    Sulfonated copoly (phthalazinone biphenyl ether sulfone) (SPPBES) composite nanofiltration membranes were fabricated by adding low molecular weight additives into SPPBES coating solutions during a dip coating process. Three selected additives: glycol, glycerol and hydroquinone were used in this work. The effect of additives on the membrane performance was studied and discussed in terms of rejection and permeation flux. Among all the composite membranes, the membrane prepared with glycol as an additive achieved the highest Na2SO4 rejection, and the membrane fabricated with glycerol as an additive exhibited the highest flux. The salts rejection of SPPBES composite membranes increased in the following order MgCl2 < NaCl ≤ MgSO4 < Na2SO4. The morphologies of the SPPBES composite membranes were characterized by SEM, it was found that the membrane prepared with hydroquinone showed a rough membrane surface. Composite membrane fabricated with glycol or glycerol as the additive showed very good chemical stability.

  17. 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.

  18. Lateral phase separation gives multiple lamellar phases in a "binary" surfactant/water system: the phase behavior of sodium alkyl benzene sulfonate/water mixtures.

    Science.gov (United States)

    Richards, Claire; Tiddy, Gordon J T; Casey, Siobhan

    2007-01-16

    We have examined the structure of the lamellar phase (Lalpha) that coexists with a micellar solution (L1) for a commercial sodium alkyl benzene sulfonate (LAS) mixed with water. The surfactant is a mixture containing C10-C13 alkyl chains, having all positional isomers of the benzene sulfonate group present except the 1-isomer. Unusually for ionic surfactants, the difference in compositions between the coexisting L1 and Lalpha phases is large (L1 = approximately 20 wt % LAS; Lalpha = approximately 65 wt %). The main technique employed was X-ray diffraction, supplemented by optical microscopy and differential scanning calorimetry (DSC). At ambient temperatures, the lamellar phase gives a single diffraction pattern with the main reflection (d) at approximately 32.5 A, whatever the composition. However, above 40 degrees C, the diffraction peak becomes broader and moves to higher d values. At higher temperatures still, several distinct and different diffraction peaks are observed, differing in detail according to composition. The largest d values (approximately 42-4 A) are observed for the lowest LAS concentrations, while the largest number of separate reflections (five) occurs for samples with approximately 44-50% LAS, both at the highest temperatures. Although there are some differences in the data between heating and cooling cycles, the d values return to the original value at low temperature. There are no observable transitions in DSC, nor is there any heterogeneity in the lamellar phase observable by microscopy. The data clearly indicate that there is some lateral separation of the different LAS isomers within the bilayers, which results in the formation of local lamellar regions having different surfactant compositions. This lateral phase separation may arise from the presence of an (electrostatic) attractive interaction, which gives rise to an upper consolute loop within the lamellar phase region of a pure LAS isomer. Similar mechanisms may occur in biological

  19. 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.

  20. 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.

  1. Poly (ether ether ketone) derivatives: Synthetic route and characterization of nitrated and sulfonated polymers

    Energy Technology Data Exchange (ETDEWEB)

    Conceicao, T.F.; Bertolino, J.R. [Grupo de Estudo em Materiais Polimericos-Departamento de Quimica, Universidade Federal de Santa Catarina, Florianopolis, SC (Brazil); Barra, G.M.O. [Departamento de Engenharia Mecanica, Universidade Federal de Santa Catarina, Florianopolis, SC (Brazil); Pires, A.T.N. [Grupo de Estudo em Materiais Polimericos-Departamento de Quimica, Universidade Federal de Santa Catarina, Florianopolis, SC (Brazil)], E-mail: alfredotiburcio@pq.cnpq.br

    2009-03-01

    Nitrated and sulfonated poly (ether ether ketone) [SNPEEK] samples were prepared through sulfonation of nitrated PEEK (NPEEK) at different temperatures resulting in polymers with distinct sulfonation degrees (SD). The sulfonation occurred preferentially in the hydroquinone segment even after 81% of this moiety had been nitrated. Sulfonation in the benzophenone moiety was achieved only in 16% of this segment at the reaction temperature of 80 deg. C. The substitution degree was obtained through the TG curves, and values were in agreement with {sup 1}H NMR data when SD is much higher as ND (nitration degree). The highest SD obtained was 72%. Membranes of the sulfonated and nitrated PEEK (SNPEEK) were prepared by casting and showed good ductility depending on the substitution degree, with proton conductivity in the order of 10{sup -2} S cm{sup -1}, an important characteristic in some applications, such as in fuel cells.

  2. 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.

  3. 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.

  4. 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...

  5. 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.

  6. 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.

  7. Arylative Desulfonation of Diarylmethyl Phenyl Sulfone with Arenes Catalyzed by Scandium Triflate.

    Science.gov (United States)

    Nambo, Masakazu; Ariki, Zachary T; Canseco-Gonzalez, Daniel; Beattie, D Dawson; Crudden, Cathleen M

    2016-05-20

    A scandium-triflate-catalyzed arylative desulfonation of diarylmethyl phenyl sulfones with arenes and heteroarenes was established. A variety of both sulfone and arene substrates were reacted to afford symmetric and nonsymmetric triarylmethanes in good yields. Further transformations of the resulting triarylmethanes and application to the concise synthesis of a bactericidal agent analogue were also demonstrated. PMID:27124389

  8. Sulfonate Functionalisation of Transition Metal Complexes: A Versatile Tool Towards Catalyst Recovery

    NARCIS (Netherlands)

    Virboul, M.A.N.

    2011-01-01

    This thesis describes the synthesis and application of sulfonate-functionalised ligands in organometallic chemistry and (aqueous) catalysis. Due to their ability to trigger specific solubility, different NHC ligand precursors bearing a butyl-sulfonate chain were synthesised. The formation of transit

  9. 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.

  10. 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.

  11. Low-level Determination of Residual Methyl Methane Sulfonate and Ethyl Methane Sulfonate in Pharmaceuticals by Gas Chromatography with Mass Spectrometry

    OpenAIRE

    M. Sarat; M. Ramakrishna; Y. Suresh; S. Harikrishna; C. Rambabu; Kishore, K.; K. Nagabhushana Reddy

    2010-01-01

    A capillary gas chromatographic method using mass spectrometric detection was developed and validated for the trace analysis (ppm level) of methyl methane sulfonate and ethyl methane sulfonate in pharmaceutical drug substances. The method utilizes a capillary column (DB-624) with 6% cyanopropyl phenyl and 94% dimethyl polysiloxane stationary phase. A dissolve-and-injection approach was adopted for sample introduction in a split less mode. Mixture of (80:20) ratio of methanol and chloroform wa...

  12. 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.

  13. 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)

  14. A model survey meter using undoped poly (ether sulfone)

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Hidehito, E-mail: hidehito@rri.kyoto-u.ac.jp [Kyoto University, 2, Asashiro-Nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan); National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Shirakawa, Yoshiyuki [National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Kanayama, Masaya; Sato, Nobuhiro [Kyoto University, 2, Asashiro-Nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan); Kitamura, Hisashi [National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Takahashi, Sentaro [Kyoto University, 2, Asashiro-Nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan)

    2015-04-21

    The large region surrounding the damaged Fukushima Daiichi Nuclear Power Plant has necessitated the use of numerous radiation survey meters with large, robust substrates. The survey meters require efficient scintillation materials that do not require doping and have dimensional stability, such as poly (ether sulfone) (PES) resins. Here, we demonstrate the performance of a model survey meter that uses large PES plates with polished, mirrored surfaces and rough, scattering surfaces. Light collection efficiencies from plates having one or more of these surfaces were quantitatively Characterised with {sup 36}Cl-, {sup 60}Co-, {sup 137}Cs-radioactive sources. The count rates of plates having a combination of mirrored/scattering-surfaces are >1.6 times that for plates having two mirrored surfaces. In addition, a significant amount of radiation-induced light generated in the PES is trapped inside the plate because of its relatively high refractive index. The results indicate that large, undoped PES plates can be used in radiation survey meters. - highlights: • Undoped poly (ether sulfone) (PES) can be used as a scintillation material in radiation survey meters. • Large PES plates with treated surfaces were characterized. • Surface roughening of the plates increased light collection efficiency. • Plates with a combination of mirrored/scattering surfaces work best. • A significant amount of light generated by radiation remains in the PES plates.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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......Formation of sulfonic anhydride S-O-S (from the condensation of sulfonic acids) was known one of the important degradation mechanisms [i] for Nafion membrane under hydrothermal aging condition, which is especially critical for hydrogen fuel cells. Similar mechanism would also have be desirable...

  5. 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.

  6. 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.

  7. 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.

  8. Synthesis and Characterization of Sulfonated Poly( phenylene sulfide sulfone)%磺化聚苯硫醚砜的制备和性能表征

    Institute of Scientific and Technical Information of China (English)

    肖慧; 李涛; 胡祥; 李瑞海

    2011-01-01

    This paper studied on sulfonated process of sulfonated poly(phenylene sulfide sulfone) based on sulfuric aid as solvent and oleum as sulfonating agent. By changing the four factors, such as temperature, reaction time, the dosage of sulfuric acid and oleum, the sulfonated conditions were explored. The structures and properties of the obtained polymer were characterized by FT-IR, TGA, testing of solubility, sulfonation degree and reduced inherent viscosity. The results indicated the sulfonation degree was 62. 2% and reduced inherent viscosity was 0. 964 mL/g when the raction temperature was at 15℃, the sulfonated time was for 2 h, sulfuric aid was 8 mL and the ratio of oleum/PPSS was 9. 5. Decomposition temperature of sulfonic aid group and its main chain were 346℃, 534 % , respectively. It can be dissolved improvably in the polar solvent which dialectic constant exceeded 20.7.%以浓硫酸为溶剂,发烟硫酸为磺化剂对聚苯硫醚砜的磺化过程,通过改变温度、反应时间、浓硫酸的用量和发烟硫酸的用量这四个因素来探究磺化反应的条件.利用FTIR、热重分析(TGA)、磺化度、比浓黏度和溶解性测试对其结构和性能进行了表征.结果表明,采用磺化时间为2h,反应温度15℃,浓硫酸8 mL,发烟硫酸与聚苯硫醚砜的质量比为9.5时,可得到磺化度为62.2%,比浓黏度为0.964 mL/g的磺化聚苯硫醚砜.磺酸基的主要分解温度为346℃,主链的分解温度为534℃.其溶解性得到提高,可溶解在介电常数大于20.7的有机溶剂中.

  9. Measurements of photo-oxidation products from the reaction of a series of alkyl-benzenes with hydroxyl radicals during EXACT using comprehensive gas chromatography

    Directory of Open Access Journals (Sweden)

    J. F. Hamilton

    2003-01-01

    Full Text Available Photo-oxidation products from the reaction of a series of alkyl-benzenes, (benzene, toluene, p-xylene and 1,3,5-trimethyl-benzene with hydroxyl radicals in the presence of NOx have been investigated using comprehensive gas chromatography (GCxGC. A GCxGC system has been developed which utilises valve modulation and independent separations as a function of both volatility and polarity. A number of carbonyl-type compounds were identified during a series of reactions carried out at the European Photoreactor (EUPHORE, a large volume outdoor reaction chamber in Valencia, Spain. Experiments were carried as part of the EXACT project (Effects of the oXidation of Aromatic Compounds in the Troposphere. Two litre chamber air samples were cryo-focused, with a sampling frequency of 30 minutes, allowing the evolution of species to be followed over oxidation periods of 3-6 hours. To facilitate product identification, several carbonyl compounds, which were possible products of the photo-oxidation, were synthesised and used as reference standards. For toluene reactions, observed oxygenated intermediates found included the co-eluting pair a-angelicalactone/4-oxo-2-pentenal, maleic anhydride, citraconic anhydride, benzaldehyde and p-methyl benzoquinone. In the p-xylene experiment, the products identified were E/Z-hex-3-en-2,5-dione and citraconic anhydride. For 1,3,5-TMB reactions, the products identified were 3,5-dimethylbenzaldehyde, 3,5-dimethyl-3H-furan-2-one and 3-methyl-5-methylene-5H-furan-2-one. Preliminary quantification was carried out on identified compounds using liquid standards. Comparison of FTIR and GCxGC for the measurement of the parent aromatics generally showed good agreement. Comparison of the concentrations observed by GCxGC to concentration-time profiles simulated using the Master Chemical Mechanism, MCMv3, demonstrates that this mechanism significantly over-predicts the concentrations of many product compounds and highlights the

  10. Surface adsorption of sulfonated poly(phenylene sulfone)/C14TAB mixtures and its correlation with foam film stability.

    Science.gov (United States)

    Uhlig, Martin; Miller, Reinhard; Klitzing, Regine von

    2016-07-21

    Polyelectrolyte/surfactant mixtures of rigid monosulfonated poly(phenylene sulfone) (sPSO2-220) and tetradecyl trimethylammonium bromide (C14TAB) were investigated by surface tension, surface elasticity and foam film stability measurements. The results were compared to former measurements of polyelectrolyte/surfactant mixtures containing more flexible polyelectrolytes (PAMPS or PSS and C14TAB). For all polyelectrolyte/surfactant mixtures an increased surface adsorption in comparison to the pure surfactant was detected. Moreover, sPSO2-220/C14TAB mixtures showed a much higher surface activity and foam film stability than mixtures with more flexible polyelectrolytes. The results presented give insight into the surface adsorption and foam film formation of rigid polyelectrolyte/surfactant mixtures. Therefore, this study helps to understand the role of polyelectrolyte backbone rigidity in the formation and stabilization of foam films made from polyelectrolyte/surfactant mixtures. PMID:27338310

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. Synthesis and characterizations of electrospun sulfonated poly (ether ether ketone) SPEEK nanofiber membrane

    Science.gov (United States)

    Hasbullah, N.; Sekak, K. A.; Ibrahim, I.

    2016-07-01

    A novel electrospun polymer electrolyte membrane (PEM) based on Sulfonated Poly (ether ether ketone) were prepared and characterized. The poly (ether ether ketone) PEEK was sulfonated using concentrated sulfuric acid at room temperature for 60 hours reaction time. The degree sulfonation (DS) of the SPEEK are 58% was determined by H1 NMR using area under the peak of the hydrogen shielding at aromatic ring of the SPEEK. Then, the functional group of the SPEEK was determined using Fourier transfer infrared (FTIR) showed O-H vibration at 3433 cm-1 of the sulfonated group (SO2-OH). The effect of the solvent and polymer concentration toward the electrospinning process was investigated which, the DMAc has electrospun ability compared to the DMSO. While, at 20 wt.% of the polymer concentration able to form a fine and uniform nanofiber, this was confirmed by FESEM that shown electrospun fiber mat SPEEK surface at nano scale diameter.

  16. Molecular Dynamics of Film Formation of Metal Tetra sulfonated Phthalocyanine and Poly Amidoamine Demanders

    International Nuclear Information System (INIS)

    We performed molecular dynamics computer simulations to elucidate the behavior and properties of the metal tetra sulfonated phthalocyanine molecule and the poly(amidoamine) dendrimers in self-assembly depositions, respectively, on poly(allylamine hydrochloride) polymer and on film formed by metal tetra sulfonated phthalocyanine with poly(allylamine hydrochloride). Important physical properties of phthalocyanines were obtained such as the kinetic energy and temperature in situ. By the semiempirical model, we also obtained the UV-Vis absorption spectrum of the film formed by cobalt tetra sulfonated phthalocyanine deposited on poly(allylamine hydrochloride). We performed a study with poly(amidoamine) dendrimers on their deposition time on metal tetra sulfonated phthalocyanine, poly(allylamine hydrochloride) film, and we show the relationship of deposition time with the electrical charge and molecular mass of phthalocyanines. The deposition times of the dendrimers, as a function of their mass, were also elucidated.

  17. Effect of sulfonation and diethanolamine addition on the mechanical and physicochemical properties of SEPS copolymer

    Science.gov (United States)

    Patiño, D.; Correa, E.; Acevedo-Morantes, M.

    2016-02-01

    Modification techniques have been developed to achieve changes in the processing of polymers, and modification of their mechanical, thermal and morphological properties, as well as their hydrophobicity and conductivity. Sulfonation improves ion conductivity, antistatic behaviour, hydrophilicity and solubility of the polymers. These characteristics are related to the presence of sulfonic groups in the polymer matrix. This research project focuses on the evaluation of mechanical, physical and chemical properties of membranes that are based on a sulfonated Styrene-Ethylene-Propylene-Styrene (SEPS) copolymer. The membranes were functionalized with diethanolamine at 5, 15 and 30% w/w, to separate carbon dioxide. FTIR and XRD analyses were used to characterize the membranes. The sulfonated-loaded membrane with 15% of diethanolamine showed the best results in each characterization.

  18. 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.

  19. 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.

  20. 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...

  1. Sulfonated mesoporous silica–carbon composites and their use as solid acid catalysts

    OpenAIRE

    Valle Vigón, Patricia; Sevilla Solís, Marta; Fuertes Arias, Antonio Benito

    2012-01-01

    [EN] The synthesis of highly functionalized porous silica–carbon composites made up of sulfonic groups attached to a carbon layer coating the pores of three types of mesostructured silica (i.e. SBA-15, KIT-6 and mesocellular silica) is presented. The synthesis procedure involves the following steps: (a) removal of the surfactant, (b) impregnation of the silica pores with a carbon precursor, (c) carbonization and (d) sulfonation. The resulting silica–carbon composites contain ∼30 wt % of carbo...

  2. Sulfonate Functionalisation of Transition Metal Complexes: A Versatile Tool Towards Catalyst Recovery

    OpenAIRE

    Virboul, M.A.N.

    2011-01-01

    This thesis describes the synthesis and application of sulfonate-functionalised ligands in organometallic chemistry and (aqueous) catalysis. Due to their ability to trigger specific solubility, different NHC ligand precursors bearing a butyl-sulfonate chain were synthesised. The formation of transition metal complexes containing gold and rhodium was enabled by a simple procedure involving the initial synthesis of a silver complex and a transmetallation with a suitable metal precursor and an o...

  3. 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

  4. 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.

  5. Sulfonation and anticoagulant activity of fungal exocellular β-(1→6)-D-glucan (lasiodiplodan).

    Science.gov (United States)

    Vasconcelos, Ana Flora D; Dekker, Robert F H; Barbosa, Aneli M; Carbonero, Elaine R; Silveira, Joana L M; Glauser, Bianca; Pereira, Mariana Sá; Corradi da Silva, Maria de Lourdes

    2013-02-15

    An exocellular β-(1→6)-D-glucan (lasiodiplodan) produced by a strain of Lasiodiplodia theobromae (MMLR) grown on sucrose was derivatized by sulfonation to promote anticoagulant activity. The structural features of the sulfonated β-(1→6)-D-glucan were investigated by UV-vis, FT-IR and (13)C NMR spectroscopy, and the anticoagulant activity was investigated by the classical coagulation assays APTT, PT and TT using heparin as standard. The content of sulfur and degree of substitution of the sulfonated glucan was 11.73% and 0.95, respectively. UV spectroscopy showed a band at 261 nm due to the unsaturated bond formed in the sulfonation reaction. Results of FT-IR and (13)C NMR indicated that sulfonyl groups were inserted on the polysaccharide. The sulfonated β-(1→6)-D-glucan presented anticoagulant activity as demonstrated by the increase in dose dependence of APTT and TT, and these actions most likely occurred because of the inserted sulfonate groups on the polysaccharide. The lasiodiplodan did not inhibit the coagulation tests. PMID:23399236

  6. 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

  7. Tissue Distribution Of Chloroaluminium Sulfonated Phthalocyanine In Dogs

    Science.gov (United States)

    M. M.; H. C.; Newman

    1989-06-01

    Chloroaluminum sulfonated phthalocyanine (A1PCS) was administered intravenously to clinically normal dogs, and A1PCS levels were determined in tissues using a sensitive assay. A1PCS accumulated to high levels in liver, spleen, bone marrow, kidney, and lung. These tissue levels confirm previous determinations in mice and rats. Only a small amount of dye was retained in skin and very small amounts in muscle and brain. A1PCS was cleared from the blood within 24 h, and excreted primarily by urine. Serum clearance was faster in males than in females. There were also significant tissue distribution differences between the genders, particularly during the first 12 h. The low levels of A1PCS in skin suggest that cutaneous photosensitivity and toxic skin reactions using this photosensitizer in photodynamic therapy of cancer may be eliminated. The difference in tissue distribution between genders is not only intriguing, but indicates that the optimal time window for treatment of various tissue sites may vary by gender.

  8. 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.

  9. An analytical model for the conductivity of polymeric sulfonated membranes

    Energy Technology Data Exchange (ETDEWEB)

    Pisani, L.; Valentini, M.; Hofmann, D.H.; Kuleshova, L.N.; D' Aguanno, B. [CRS4, Parco Scientifico e Tecnologico, Polaris, 09010, Pula (Italy)

    2008-06-15

    In this work, we present a new approach to model the conductivity of polymeric sulfonated membranes. In the first part, we develop a model for the proton conductivity in a bulk acid solution. The model describes the vehicular and structural diffusion mechanisms at different proton concentrations as a function of four parameters with well defined physical meanings. These parameters are adjusted by fitting the experimental proton conductivity in a hydrochloric acid solution. In the second part, the effects of the presence of the porous membrane on the proton conductivity are added to the model. As a result, the model predicts the membrane conductivity as a function of its hydration level and porous structure. In the absence of experimental data on the membrane porous structure, the model can be used to predict the membrane porous structure once membrane conductivities are experimentally known. In this scope, in the third part, we provide a simple analytical description of the porous membrane based on the percolation theory depending on two structure parameters. A side result of the conductivity model is to provide analytical expressions for the drag coefficient, pore diameters and water permeability. All obtained results compare very well with experimental data. (author)

  10. 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.

  11. 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.

  12. 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.

  13. Activity coefficients at infinite dilution of hydrocarbons, alkylbenzenes, and alcohols in the paramagnetic ionic liquid 1-butyl-3-methyl-imidazolium tetrachloridoferrate(III) using gas-liquid chromatography

    International Nuclear Information System (INIS)

    Activity coefficients at infinite dilution γi∞ of alkanes, alkenes, and alkylbenzenes as well as of the linear C1-C6 alcohols in the paramagnetic ionic liquid 1-butyl-3-methyl-imidazolium tetrachloridoferrate(III) have been determined by gas chromatography using the ionic liquids as stationary phase. The measurements were carried out at different temperatures between (305 and 403) K. From the temperature dependence of the limiting activity coefficients partial molar excess enthalpies at infinite dilution HiE,∞ of the solutes in the ionic liquids have been derived. Activity coefficients at infinite dilution γi∞ of ionic liquid with the ionic liquids containing 1-butyl-3-methyl-imidazolium cation and different non-magnetic anions have been compared at 298 K with results for 1-butyl-3-methyl-imidazolium tetrachloridoferrate(III). No significant effects caused by the paramagnetic anion anion have been observed

  14. 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.

  15. 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.

  16. 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.

  17. Las fronteras del istmo

    OpenAIRE

    Affre, Nathalie; Alvarenga, Patricia; Arriola, Aura Marina; Bastian, Jean-Pierre; Bovin, Philippe; Burne, Stella Maris Arnaiz; Carrillo, Ana Lorena; Casillas R, Rodolfo; Castillo, Manuel Ángel; Córdova, Juan Pohlenz; Cosío, María Eugenia Zavala de; Dachary, Alfredo César; Dauzier, Martine; Demyk, Noelle; Douzant-Rosenfeld, Denise

    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...

  18. Nitric Acid Dehydration Using Perfluoro Carboxylate and Mixed Sulfonate/Carboxylate Membranes

    Energy Technology Data Exchange (ETDEWEB)

    R.L. Ames

    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

  19. Ag (I)-based 2D metal frameworks with helical structures decorated by the homochiral camphor-10-sulfonic acid

    Science.gov (United States)

    Guo, Peng; Wang, Jing; Wang, Jun; Pan, Daocheng; Xu, Guohai

    2010-12-01

    Two two-dimension homochiral Ag (I) metal frameworks constructed from enantiopure camphor-10-sulfonic acid and hexamethylenetetramine have been synthesized at the room temperature. These two complexes with (6, 3) topology decorated by the homochiral camphor-10-sulfonic acid possess the unique helical structures. The result of Circular Dichroism (CD) spectroscopy confirms that the bulk materials are homochiral and also indicates the handedness of the single crystals can be controlled by the chirality of the camphor-10-sulfonic acid.

  20. Surface modification of carbon fibers by a polyether sulfone emulsion sizing for increased interfacial adhesion with polyether sulfone

    Science.gov (United States)

    Yuan, Haojie; Zhang, Shouchun; Lu, Chunxiang

    2014-10-01

    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.

  1. 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)

  2. 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.

  3. 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.

  4. 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...

  5. Grafting titanium nitride surfaces with sodium styrene sulfonate thin films.

    Science.gov (United States)

    Zorn, Gilad; Migonney, Véronique; Castner, David G

    2014-09-01

    The importance of titanium nitride lies in its high hardness and its remarkable resistance to wear and corrosion, which has led to its use as a coating for the heads of hip prostheses, dental implants and dental surgery tools. However, the usefulness of titanium nitride coatings for biomedical applications could be significantly enhanced by modifying their surface with a bioactive polymer film. The main focus of the present work was to graft a bioactive poly(sodium styrene sulfonate) (pNaSS) thin film from titanium nitride surfaces via a two-step procedure: first modifying the surface with 3-methacryloxypropyltrimethoxysilane (MPS) and then grafting the pNaSS film from the MPS modified titanium through free radical polymerization. X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) were used after each step to characterize success and completeness of each reaction. The surface region of the titanium nitride prior to MPS functionalization and NaSS grafting contained a mixture of titanium nitride, oxy-nitride, oxide species as well as adventitious surface contaminants. After MPS functionalization, Si was detected by XPS, and characteristic MPS fragments were detected by ToF-SIMS. After NaSS grafting, Na and S were detected by XPS and characteristic NaSS fragments were detected by ToF-SIMS. The XPS determined thicknesses of the MPS and NaSS overlayers were ∼1.5 and ∼1.7 nm, respectively. The pNaSS film density was estimated by the toluidine blue colorimetric assay to be 260 ± 70 ng/cm(2). PMID:25280842

  6. 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.

  7. 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

  8. Enhanced osteoblast-like cell adhesion and proliferation using sulfonate-bearing polymeric scaffolds.

    Science.gov (United States)

    Chaterji, Somali; Gemeinhart, Richard A

    2007-12-15

    Orthopedic malfunction, degeneration, or damage remains a serious healthcare issue despite advances in medical technology. Proactive extracellular matrix (ECM)-mimetic scaffolds are being researched to orchestrate the activation of diverse osteogenic signaling cascades, facilitating osteointegration. We hypothesized that sulfonated functionalities incorporated into synthetic hydrogels would simulate anionic, sulfate-bearing proteoglycans, abundant in the ECM. Using this rationale, we successfully developed differentially sulfonated hydrogels, polymerizing a range of sulfopropyl acrylate potassium-acrylamide (SPAK-AM) mole ratios as monomer feeds under room temperature conditions. For anchorage-dependent cells, such as osteoblasts, adhesion is a critical prerequisite for subsequent osteointegration and cell specialization. The introduction of the sulfonated monomer, SPAK, resulted in favorable uptake of serum proteins with proportional increase in adhesion and proliferation rates of model cell lines, which included NIH/3T3 fibroblasts, MG-63 osteoblasts, and MC3T3-E1 subclone 4 preosteoblasts. In fact, higher proportions of sulfonate content (pSPAK75, pSPAK100) exhibited comparable or even higher degrees of adhesion and proliferation, relative to commercial grade tissue culture polystyrene in vitro. These results indicate promising potentials of sulfonated ECM-mimetic hydrogels as potential osteogenic tissue engineering scaffolds. PMID:17584889

  9. 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.

  10. [New synthesis of the anticoagulant pentasaccharide idraparinux and preparation of its analogues containing sulfonic acid moieties].

    Science.gov (United States)

    Herczeg, Mihály

    2012-01-01

    Two novel synthetic pathways were elaborated for the preparation of idraparinux, a heparin-related fully O-sulfated, O-methylated anticoagulant pentasaccharide. Both methods based upon a [2+3] block synthesis utilizing the same trisaccharide acceptor which was coupled to either a uronic acid disaccharide donor or its nonoxidized precursor. Two bioisosteric sulfonic acid analogues of idraparinux were also prepared, in which two or three primary sulfate esters were replaced by sodium-sulfonatomethyl moieties. The sulfonic acid groups were formed on a monosaccharide level and the obtained carbohydrate sulfonic acid esters were found to be excellent donors and acceptors in the glycosylation reactions. The disulfonic-acid analogue was prepared in a [2+3] block synthesis by using a trisaccharide disulfonic acid as an acceptor and a glucuronide disaccharide as a donor. For the synthesis of the pentasaccharide trisulfonic acid, a more-efficient approach, which involved elongation of the trisaccharide acceptor with a non-oxidized precursor of the glucuronic acid followed by post-glycosidation oxidation at the tetrasaccharide level and a subsequent [1+4] coupling reaction, was elaborated. In vitro evaluation of the anticoagulant activity of the reference compound idraparinux and the new sulfonic acid derivatives revealed that the disulfonate analogue inhibited the blood-coagulation-proteinase factor Xa with outstanding efficacy; however, the introduction of the third sulfonic acid moiety resulted in a notable decrease in the anti-Xa activity. PMID:23230650

  11. 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.

  12. Tin Coatings Electrodeposited from Sulfonic Acid-Based Electrolytes: Tribological Behavior

    Science.gov (United States)

    Bengoa, L. N.; Tuckart, W. R.; Zabala, N.; Prieto, G.; Egli, W. A.

    2015-06-01

    A high efficiency methane sulfonic acid electrolyte used for tin electrodeposition was studied, and the properties of the resulting deposits were compared to those of tin coatings obtained from an industrial phenol sulfonic acid electrolyte. Cyclic voltammetry was used to study the effect of organic additives on the reduction process to define the composition of the electrolytic bath. Thick tin electrodeposits were obtained on rotating cylinder steel electrodes, and their surface morphology, preferred crystal orientation, surface roughness, micro hardness, and tribological behavior were measured. Smooth, adherent, and bright tin coatings were obtained from the methane sulfonic acid electrolyte, which differed in morphology and texture from tin electrodeposited from the industrial bath. Influence of organic additives on preferred crystal orientation of the coatings was found to be stronger than changing the supporting sulfonic acid type. Tribological tests showed that the two types of deposits have a similar coefficient of friction. However, tin coatings obtained from methane sulfonic electrolytes presented a lower wear resistance and underwent galling at lower loads.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Periodic Mesoporous Organosilica Functionalized with Sulfonic Acid Groups as Acid Catalyst for Glycerol Acetylation

    Directory of Open Access Journals (Sweden)

    Pascal Van Der Voort

    2013-08-01

    Full Text Available A Periodic Mesoporous Organosilica (PMO functionalized with sulfonic acid groups has been successfully synthesized via a sequence of post-synthetic modification steps of a trans-ethenylene bridged PMO material. The double bond is functionalized via a bromination and subsequent substitution obtaining a thiol functionality. This is followed by an oxidation towards a sulfonic acid group. After full characterization, the solid acid catalyst is used in the acetylation of glycerol. The catalytic reactivity and reusability of the sulfonic acid modified PMO material is investigated. The catalyst showed a catalytic activity and kinetics that are comparable with the commercially available resin, Amberlyst-15, and furthermore our catalyst can be recycled for several subsequent catalytic runs and retains its catalytic activity.

  18. 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.

  19. Synthesis of linear alkylbenzene sulphonate intercalated iron(II) iron(III) hydroxide sulphate (green rust) and adsorption of carbon tetrachloride

    DEFF Research Database (Denmark)

    Ayala Luis, Karina Barbara; Kaldor, D.K.; Bender Koch, Christian;

    2007-01-01

    Green rusts, GRs, can act as both sorbents and reductants towards selected pollutants. Organo-GRs are expected to combine these properties with a high affinity for hydrophobic substances. A novel organo-GR, GRLAS, was synthesized by incorporating a mixture of linear alkylbenzenesulphonates (LAS) ...

  20. Particle size effects of sulfonated graphene supported Pt nanoparticles on ethanol electrooxidation

    International Nuclear Information System (INIS)

    Highlights: • Pt colloidal nanoparticles with five mean diameters are synthesized. • Size-selected Pt nanoparticles are loaded on sulfonated graphene (sG). • Sulfonic acid functional groups atop graphene donate charge to Pt. • Pt-sG catalysts are used for ethanol oxidation reaction (EOR). • Pt-sG(2.5 nm) has the highest peak current density in EOR. - Abstract: Fuel cells are promising alternative in automobile and stationary power generation. Direct ethanol fuel cells (DEFCs) offer significant advantages due to the non-toxicity and renewability of ethanol as well as its high power density. Development of the efficient catalysts for ethanol oxidation reaction (EOR) has attracted great attention and represents one of the major challenges in electrocatalysis. Graphene, one-atom thick nanocarbon materials, has attracted much attention recently in a variety of applications. The sulfonation of graphene is able to make it hydrophilic, which enhances its dispersibility in aqueous solvents. Furthermore, sulfonation increases the adsorption and uniform distribution of the Pt nanoparticles, which increases both the electrocatalytic activity and the durability. In this study, theoretical calculations demonstrated that the sulfonate functional group can donate charge to Pt, enhanced the adsorption energy of Pt, and then reduce the adsorption energy of CO on Pt. Then experimentally five kinds of Pt/sulfonated-graphene (Pt/sG) catalysts were synthesized via the control of pH values during the preparation of five-selected colloidal nanoparticles. Among all catalysts, Pt-sG(2.5 nm) has the highest peak current density in EOR

  1. 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.

  2. 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...

  3. A Facile and Mild Synthesis of Trisubstituted Allylic Sulfones from Morita-Baylis-Hillman Carbonates

    Directory of Open Access Journals (Sweden)

    Lin Jiang

    2015-05-01

    Full Text Available An efficient and catalyst-free synthesis of trisubstituted allylic sulfones through an allylic sulfonylation reaction of Morita-Baylis-Hillman (MBH carbonates with sodium sulfinates has been developed. Under the optimized reaction conditions, a series of trisubstituted allylic sulfones were rapidly prepared in good to excellent yields (71%–99% with good to high selectivity (Z/E from 79:21 to >99:1. Compared with known synthetic methods, the current protocol features mild reaction temperature, high efficiency and easily available reagents.

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. Las competencias laborales

    OpenAIRE

    Mucci, Ottorino Oscar

    2001-01-01

    Las tradicionales formas de calificar al personal, desde el punto de vista del empleo, han sufrido modificaciones sustanciales en los últimos tiempos. Por ello, en este trabajo se intenta -sin desechar totalmente anteriores métodos- mostrar nuevos paradigmas que implican una visualización más abarcativa y profunda entendida como premisa para determinar no solo el potencial del empleado sino también las posibilidades de éxito en su desarrollo individual y colectivo.

  9. Synthesis and properties of novel multiblock copolyimides consisting of benzimidazole-groups-containing sulfonated polyimide hydrophilic blocks and non-sulfonated polyimide hydrophobic blocks as proton exchange membranes

    International Nuclear Information System (INIS)

    A series of novel multiblock copolymers consisting of benzimidazole-groups-containing sulfonated polyimide hydrophilic blocks (averaged block length = 20) and non-sulfonated polyimide hydrophobic blocks (averaged block length = 5 or 10) have been synthesized via two-pot synthetic procedures. The anhydride-terminated hydrophilic oligomer is synthesized by copolymerization of excess 1,4,5,8-naphthalelnetetracarboxylic dianhydride (NTDA) with amine-terminated polybenzimidazole (PBI-NH2) and 4,4′-bis(4-aminophenoxy) biphenyl-3,3′-disulfonic acid (BAPBDS), while the amine-terminated hydrophobic oligomers are synthesized by polymerization of excess non-sulfonated diamines with NTDA or a fluorinated dianhydride. The resulting multiblock copolymers can be cast into tough membranes indicating that reasonably high molecular weights block copolymers have been obtained. The block SPIs exhibit microphase-separated structure, whereas the random one is amorphous. Fenton’s test reveals that the block copolymer membranes, in particular, those consisting of fluorinated hydrophobic blocks, are fairly stable toward radical oxidation. Preliminary fuel cell tests are performed to evaluate the fuel cell performance of the block copolymer membranes. The single cell equipped with the block copolymer membrane of which hydrophobic block is prepared from NTDA and a fluorinated diamine (averaged block length = 5) exhibits a peak output power density of 0.70 W/cm2 at 90 °C and 92% relative humidity for H2/air which is comparable to that of Nafion 112

  10. 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

  11. 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.

  12. 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.

  13. 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

  14. 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...

  15. 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

  16. 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.

  17. Gene expression profiling identifies mechanisms of protection to recurrent trinitrobenzene sulfonic acid colitis mediated by probiotics

    NARCIS (Netherlands)

    Mariman, R.; Kremer, S.H.A.; Erk, M. van; Lagerweij, T.; Koning, F.; Nagelkerken, L.

    2012-01-01

    Background: Host-microbiota interactions in the intestinal mucosa play a major role in intestinal immune homeostasis and control the threshold of local inflammation. The aim of this study was to evaluate the efficacy of probiotics in the recurrent trinitrobenzene sulfonic acid (TNBS)-induced colitis

  18. 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...

  19. Pharmacokinetic profiles of perfluorobutane sulfonate and activation of hepatic genes in mice

    Science.gov (United States)

    Polyfluoroalkyl substances (PFAS) are organic chemicals with wide industrial and consumer uses. They are found ubiquitously at low levels in the environment and detectable in humans and wildlife. Perfluorobutane Sulfonate (PFBS) is a short-chained PFAS used to replace perfluorooc...

  20. Perfluoroalkanesulfonamide Organocatalysts for Asymmetric Conjugate Additions of Branched Aldehydes to Vinyl Sulfones

    Directory of Open Access Journals (Sweden)

    Kosuke Nakashima

    2013-11-01

    Full Text Available Asymmetric conjugate additions of branched aldehydes to vinyl sulfones promoted by sulfonamide organocatalyst 6 or 7 have been developed, allowing facile synthesis of the corresponding adducts with all-carbon quaternary stereocenters in excellent yields with up to 95% ee.

  1. Radiation Detection: Resistivity Responses in Functional Poly(Olefin Sulfone)/Carbon Nanotube Composites

    OpenAIRE

    Swager, Timothy Manning; Lobez, Jose M.

    2009-01-01

    Detection of gamma rays is shown using a non-scintillating organic-based sensor composed of poly(olefin sulfone)/carbon nanotube blends. Functionalization of the polymers can be performed after polymerization to tailor their structure with different pyrene and bismuth-containing moieties not accessible by copolymerization, and a systematic improvement in sensitivity is achieved in this way.

  2. Multi-block sulfonated poly(phenylene) copolymer proton exchange membranes

    Science.gov (United States)

    Fujimoto, Cy H.; Hibbs, Michael; Ambrosini, Andrea

    2012-02-07

    Improved multi-block sulfonated poly(phenylene) copolymer compositions, methods of making the same, and their use as proton exchange membranes (PEM) in hydrogen fuel cells, direct methanol fuel cells, in electrode casting solutions and electrodes. The multi-block architecture has defined, controllable hydrophobic and hydrophilic segments. These improved membranes have better ion transport (proton conductivity) and water swelling properties.

  3. Polybenzimidazole and sulfonated polyhedral oligosilsesquioxane composite membranes for high temperature polymer electrolyte membrane fuel cells

    DEFF Research Database (Denmark)

    Aili, David; Allward, Todd; Alfaro, Silvia Martinez;

    2014-01-01

    Composite membranes based on poly(2,2′(m-phenylene)-5,5́bibenzimidazole) (PBI) and sulfonated polyhedral oligosilsesquioxane (S-POSS) with S-POSS contents of 5 and 10wt.% were prepared by solution casting as base materials for high temperature polymer electrolyte membrane fuel cells. With membran...

  4. 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.

  5. 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.

  6. 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.

  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. 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.

  9. social de las empresas

    Directory of Open Access Journals (Sweden)

    José Luis Lizcano Álvarez

    2006-01-01

    Full Text Available La Responsabilidad Social Corporativa se encuentra entre los principales temas del pensamiento empresarial y necesita de la crítica y el debate para afianzar su estructura, alcanzando así la coherencia necesaria. Repasando algunos reproches que se hacen a la RSC como teoría empresarial, se trata de mostrar cual es el error que en ellos se encuentra y porque no restan valor a las raíces de la responsabilidad social corporativa. Seguidamente, se expondrá algunos principios básicos del sistema, tratando de detallar las oportunidades que ofrece la responsabilidad social de la empresa al capitalismo futuro como elemento creativo y dinamizador. Además, se ofrece una visión de como la responsabilidad social corporativa puede implicar ganancias en libertad, flexibilidad y eficiencia para el conjunto de la sociedad si se orienta hacia una nueva forma de entender las relaciones entre el Estado y el sector privado con implicaciones sobre el gasto público y la carga fiscal. La propuesta de este artículo pretende abrirse camino entre las diversas aportaciones que están surgiendo en torno al desarrollo y la implantación del modelo de empresa socialmente responsable. Las conclusiones señaladas representan también el inicio de futuras líneas de trabajo de carácter técnico y empírico.

  10. Association of hydrophobic organic compounds with river particles of different sizes

    Energy Technology Data Exchange (ETDEWEB)

    Takada, Hideshige; Kumata, Hidetoshi; Satoh, Futoshi [Tokyo Univ. of Agriculture & Technology (Japan)

    1996-12-31

    Hydrophobic molecular markers are potentially useful to identify the sources and the transport pathways of hydrophobic pollutants like polychlonnated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs). Use of molecular markers for the source-identification requires consideration of the similarity and differences in environmental behaviors between the marker compounds and the pollutants. Linear alkylbenzenes (LABs), which are present in linear alkylbenzene-sulfonates (LAS) surfactants as impurities, are molecular markers of sewage-derived pollutants. Recently Sherblom et. al demonstrated that their hydrophobicities (Kong) overlap with those of PCBs and PAHs. This enhances their potential utility for mimicking the transport pathways of the hydrophobic pollutants. However, the similarity in environmental behaviors between LAB s and PCBs and PAHs has not been examined on observation. This study compared the sorption behavior of LABs with PCBs and PAHs in river water.

  11. Las sirenas de Sarhua

    Directory of Open Access Journals (Sweden)

    Luis Millones

    2011-05-01

    Full Text Available El presente artículo es producto de una investigación sobre uno de los motivos más llamativos y recurrentes en las Tablas de Sarhua: la sirena.Realizamos una aproximación a este motivo, que originalmente aparece en la literatura clásica occidental, con la finalidad de explicar las razones de su presencia en el arte andino. Para tal efecto transcribimos algunos testimoniosque, desde una cosmovisión netamente andina, dan cuenta de una serie de creencias vinculadas con el ámbito musical, en el que las sirenas juegan un papel central.Palabras claves: Tablas de Sarhua, sirena, arte andino, música andina.

  12. Las nuevas masculinidades positivas

    Directory of Open Access Journals (Sweden)

    Antonio Boscán Leal

    2008-01-01

    Full Text Available El presente estudio analiza la influencia de los avances de las mujeres en los cambios que han alterado la vida de los varones y su definición de la masculinidad. Estos cambios se expresan en el desarrollo de nuevas manifestaciones de la masculinidad, algunas de las cuales, por su carácter no sexista y no homofóbico, son catalogadas como positivas. Los rasgos de estas nuevas manifestaciones positivas de la masculinidad han sido perfilados por diferentes estudiosas y estudiosos, y aquí han sido reunidos para elaborar una concepción amplia y plural de la masculinidad, que refleje esas nuevas y múltiples formas positivas de manifestarse la misma. El problema es saber si las mujeres y sobre todo los varones están dispuestos a asumir una nueva concepción de la masculinidad como la que aquí se propone.

  13. Mass transport of direct methanol fuel cell species in sulfonated poly(ether ether ketone) membranes

    International Nuclear Information System (INIS)

    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[reg] 112 was used as reference material. DMFC tests were also performed at 50 deg. 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[reg] 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[reg] 112. However, the highest DMFC overall efficiency was achieved using sPEEK membrane with SD = 52%

  14. Single cell performance and electrochemical characterization of photocrosslinked and post-sulfonated SEBS-DVB membranes

    International Nuclear Information System (INIS)

    Highlights: • Photocrosslinked and post-sulfonated (SEBS-DVB) membranes were successfully prepared • Membranes with 25%DVB showed reduced water swelling and improved ionic conductivity • A change in morphology was observed with increasing DVB content and irradiation time • Hydrogen and electronic crossover are negligible in all cases • Best cell performance was reported for s(SEBS-DVB 75-25) irradiated for 15 minutes - ABSTRACT: This work describes the preparation of UV photocrosslinked and post-sulfonated s(SEBS-DVB) membranes for their use as proton exchange membranes (PEM). Photocrosslinking is chosen as a useful method to reduce water uptake and enhance the dimensional stability while post-sulfonation reaction prevents the possibility of sulfonic groups may photocrosslink between different molecules. The experimental membranes are evaluated and compared with pristine sSEBS in terms of IEC, swelling ratio (in water and chloroform), FTIR-ATR and thermal properties (TGA, DSC). Morphology is investigated using SEM and AFM. The membranes are fitted into single cells and electrochemically characterized in order to determine in situ through-plane proton conductivity, hydrogen crossover and cell performance at 80 °C, atmospheric pressure and 100% relative humidity. The effects exerted by crosslinkable agent amount (DVB) and irradiation time are examined. Thus, s(SEBS-DVB 75-25) irradiated for 15 minutes highlights significantly from the rest, reaching a maximum current density of about 2300 mAcm−2 and a maximum power density greater than 700 mWcm−2 while these values for sSEBS are 1700 mAcm−2 and 478 mWcm−2, respectively. The results indicate that photocrosslinking and post-sulfonation are effective approaches to reduce the problem of excessive water swelling in membranes based on sSEBS and to endue a good performance

  15. 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

  16. Capitulo dos. Las licencias

    OpenAIRE

    Aliprandi, Simone

    2014-01-01

    1. Principios básicos En primer lugar, para evitar caer en los errores más comunes acerca de las licencias Creative Commons, tenemos que establecer los principios que son válidos para todas las licencias de contenido abierto. 1.1. Una definición de "licencia de derechos de autor" Una licencia de derecho de autor es un instrumento jurídico con el que el titular de los derechos de autor regla el uso y la distribución de su trabajo. Por lo tanto, se trata de una herramienta de derecho civil que ...

  17. Analizar las interacciones virtuales

    Directory of Open Access Journals (Sweden)

    Luis Gómez Encinas

    2003-11-01

    Full Text Available El propósito de este artículo es abordar una serie de cuestiones relacionadas con las interacciones virtuales. En concreto, nos centraremos en el IRC, los comúnmente llamados chats, para a partir de una crítica a ciertos posicionamientos analíticos, expresar la necesidad de indagar en esa faceta del ciberespacio desde el punto de vista de las relaciones sociales. Nuevas relaciones sociales, que acontecen en un espacio nuevo, y que por tanto se desarrollan bajo reglas y motivaciones que desbordan los viejos esquemas de observación.

  18. Los cuidados y las mujeres en las familias Los cuidados y las mujeres en las familias

    Directory of Open Access Journals (Sweden)

    María Teresa Martín Palomo

    2008-12-01

    Full Text Available This article proposes a reflection on a debate that is generating an important theorical and empirical production: the care. In the first place, the specificity of care is explored from a point of view that includes, besides the material aspects, affective and moral ones. It stands out the complexity of care at the different dimensions that operate in this concept. Second: care is changing in our society, starting from the massive and durable arrival of women to the labor market. In the families women are mainly responsible or caring for aged population, children and other fragile people. As to this moment care has not been reorganized among the genders, they have been the women of different generations who have articulated its solidarities with available state help or appealing to the market to cover the necessities of its relatives. Howevwe, the graving deficit in the provision of family care seems to approach a point of not sustainability in the near future. Propoal of “social care” offer institutional articulation between private solidarities and public duties in the allotment of family care so tha society in general can bear to the participation of women in the labour work. This implying the return of moral responsibility in the politics of care.Este artículo propone una reflexión sobre uno de los debates que está generando una importante producción teórica y empírica en los últimos años: los cuidados. Para ello, en primer lugar, se explora la especificidad de los cuidados ampliando el enfoque desde un punto de vista que incluya, además de los aspectos materiales, aspectos afectivos y morales. Se destaca la transversalidad y enorme complejidad de los cuidados por las diferentes dimensiones que operan en dicho concepto. En segundo lugar, se revisa como se están reestructurando los cuidados en nuestra sociedad a partir de las transformaciones que ha provocado la llegada masiva y duradera de mujeres al mercado laboral, a la par

  19. 新型液固循环移动床反应器中直链烷基苯合成研究%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 AlCl3 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.

  20. Las TIC como fuente de ventaja competitiva en las PYMES

    OpenAIRE

    Álvaro Fernando Moncada Niño; Martha Lucía Oviedo Franco

    2013-01-01

    Desde su aparición, las Tecnologías de la Información y las Comunicaciones (TIC) se han convertido en un recurso fundamental de las empresas para competir en la mayoría de las industrias, generalizando el planteamiento de que son fuente de ventaja competitiva. Pero realmente, ¿cuándo las TIC son fuente potencial de ventaja competitiva para las pymes? ¿Bajo qué condiciones se logra que contribuyan a generar valor y mejorar su posición competitiva? ¿Qué características deben cumplir para alcanz...

  1. Las voces del silencio

    Directory of Open Access Journals (Sweden)

    María Angélica Semilla Durán

    2010-10-01

    Full Text Available The article analyses the novel by Carlos Gamerro El secreto y las voces in the framework of the texts studying the memory issues of the last Argentinian dictatorship. The purpose here is to shed light on the narrative devices used to describe the logical manipulations, the verbal shift and the social mechanisms that contributed to configure a society globally accomplice of the crimes committed by the dictatorship, be it by naturalization or concealment. The silence plot is difficult to counter, and when the speech finally returns, it carries other unsensed secrets and shows that all the consciences have, in one way or another, lacked vigilance.El artículo analiza la novela de Carlos Gamerro El secreto y las voces, inscribiéndola en el marco de los textos que trabajan sobre la memoria de la última dictadura argentina. Se trata de poner en evidencia los procedimientos narrativos utilizados para describir las manipulaciones lógicas, los desvíos verbales y los mecanismos sociales qui contribuyeron a configurar una sociedad globalmente pasiva, cómplice en cierta medida de los crímenes de la dictadura, por naturalización u ocultación. Es difícil quebrar el complot del silencio, y cuando la palabra se libera finalmente,  porta otros secretos imprevistos y muestra que todas las consciencias, de una manera u otra, han fallado al deber de vigilancia.

  2. Las competencias emocionales

    Directory of Open Access Journals (Sweden)

    Rafael Bisquerra Alzina

    2007-01-01

    Full Text Available El concepto de competencia está en revisión debido a su complejidad. Hay diversas categorías de competencias: técnicas, profesionales, participativas, personales, básicas, clave, genéricas, transferibles, emocionales, socio-emocionales, etc. En este trabajo se toman en consideración las competencias emocionales, entendidas como un subconjunto de las competencias personales. Se exponen los trabajos en torno a estas competencias y se aporta una conceptualización y una sistemática estructurada en cinco grandes bloques: conciencia emocional, regulación emocional, autonomía emocional, competencia social, habilidades de vida y bienestar. Se hace referencia a las aplicaciones de las competencias emocionales en la empresa, la salud y la educación. De cara a la clarificación de conceptos, se establece la distinción entre inteligencia emocional, competencia emocional y educación emocional.

  3. Las marcas no tradicionales

    Directory of Open Access Journals (Sweden)

    Juan David Castro

    2012-11-01

    Full Text Available Las transformaciones en el comercio tanto nacional como internacionalmente han hecho necesario el aparecimiento de nuevas formas de manifestación de los signos destinados a diferenciar los productos y servicios en el mercado. El artículo reseña algunos de ellos.

  4. SOLVENT-FREE FACILE SYNTHESIS OF NOVEL α-TOSYLOXY β-KETO SULFONES USING [HYDROXY(TOSYLOXY)IODO]BENZENE

    Science.gov (United States)

    A facile, general and high yielding protocol for the synthesis of novel α-tosyloxy β-keto sulfones is described utilizing relatively non-toxic, [hydroxy(tosyloxy)iodo]benzene, under solvent-free conditions at room temperature.

  5. 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.

  6. endo-3,3-Dimethyl-4-oxobicyclo-[3.1.0]hexan-2-yl methane-sulfonate.

    Science.gov (United States)

    Kremer, Adrian; Norberg, Bernadette; Krief, Alain; Wouters, Johan

    2010-01-01

    The relative configuration of the endo isomer of the title compound, C(9)H(14)O(4)S, has been established and the conformation of the diastereoisomer is discussed. The five-membered ring adopts an envelope conformation. The conformation of the methane-sulfonate substituent is stabilized by inter-molecular C-H⋯O hydrogen bonds. The crystal packing results in alternating layers of polar methane-sulfonates and stacked bicyclo-hexa-nyl rings parallel to ab. PMID:21580752

  7. 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.

  8. Improving the Conductivity of Sulfonated Polyimides as Proton Exchange Membranes by Doping of a Protic Ionic Liquid

    OpenAIRE

    Bor-Kuan Chen; Jhong-Ming Wong; Tzi-Yi Wu; Lung-Chuan Chen; I-Chao Shih

    2014-01-01

    Proton exchange membranes (PEMs) are a key component of a proton exchange membrane fuel cell. Sulfonated polyimides (SPIs) were doped by protic ionic liquid (PIL) to prepare composite PEMs with substantially improved conductivity. SPIs were synthesized from diamine, 2,2-bis[4-(4-amino-phenoxy)phenyl]propane (BAPP), sulfonated diamine, 4,4'-diamino diphenyl ether-2,2'-disulfonic acid (ODADS) and aromatic anhydride. BAPP improved the mechanical and thermal properties of SPIs, while ODADS enhanc...

  9. Adsorption behavior of perfluorinated sulfonic acid ionomer on highly graphitized carbon nanofibers and their thermal stabilities

    DEFF Research Database (Denmark)

    Andersen, Shuang Ma; Borghei, Maryam; Dhiman, Rajnish;

    2014-01-01

    isotherm), the ionomer has varying affinities for CNFs (Keq. = between 5 and 22) as compared to Vulcan (Keq. = 18), depending on surface treatments. However, the interactions are most likely governed by different adsorption mechanisms depending on hydrophilicity / hydrophobicity of the adsorbent carbon......A systematic adsorption study of perfluorinated sulfonic acid Nafion® ionomer on ribbon type highly graphitized carbon nanofibers (CNFs) was carried out using 19 fluorine nuclear magnetic resonance spectroscopy. Based on the values obtained for the equilibrium constant (Keq., derived from Langmuir....... The ionomer is probably adsorbed via the polar sulfonic group on hydrophilic Vulcan, whereas, it is adsorbed primarily via hydrophobic -CF2- backbone on the highly hydrophobic pristine CNFs. Ionomer adsorption behavior is gradually altered from apolar to polar group adsorption for the acid modified CNFs...

  10. Enhancement of proton conductivity of sulfonated polystyrene membrane prepared by plasma polymerization process

    Indian Academy of Sciences (India)

    Bhabesh Kumar Nath; Aziz Khan; Joyanti Chutia; Arup Ratan Pal; Heremba Bailung; Neelotpal Sen Sarma; Devasish Chowdhury; Nirab Chandra Adhikary

    2014-12-01

    This work reports the achievement of higher proton conductivity of polystyrene based proton exchange membrane synthesized in a continuous RF plasma polymerization process using two precursors, styrene (C8H8) and trifluoromethane sulfonic acid (CF3SO3H). The chemical composition of the developed membranes is investigated using Fourier transform infrared spectroscopy and energy dispersive spectroscopy. Scanning electron microscopy has been used for the study of surface morphology and thickness measurement of the membrane. The membranes deposited in the power range from 0.114 to 0.318 Wcm-2 exhibit a lot of variation in the properties like proton transport, water uptake, sulfonation rate, ion exchange capacity and thermal behaviour. The proton conductivity of the membranes is achieved up to 0.6 Scm-1, measured with the help of potentiostat/galvanostat. The thermogravimetric study of the plasma polymerized membrane shows the thermal stability up to 140 °C temperature.

  11. Meaning of leprosy for people who have experienced treatment during the sulfonic and multidrug therapy periods

    Directory of Open Access Journals (Sweden)

    Karen da Silva Santos

    2015-08-01

    Full Text Available AbstractObjective: to analyze the meanings of leprosy for people treated during the sulfonic and multidrug therapy periods.Method: qualitative nature study based on the Vigotski's historical-cultural approach, which guided the production and analysis of data. It included eight respondents who have had leprosy and were submitted to sulfonic and multidrug therapy treatments. The participants are also members of the Movement for Reintegration of People Affected by Leprosy.Results: the meanings were organized into three meaning cores: spots on the body: something is out of order; leprosy or hanseniasis? and leprosy from the inclusion in the Movement for Reintegration of People Affected by Leprosy.Conclusion: the meanings of leprosy for people submitted to both regimens point to a complex construction thereof, indicating differences and similarities in both treatments. Health professionals may contribute to the change of the meanings, since these are socially constructed and the changes are continuous.

  12. Esterification of levulinic acid into ethyl levulinate catalysed by sulfonated hydrothermal carbons

    Institute of Scientific and Technical Information of China (English)

    Filoklis D. Pileidis; Maham Tabassum; Sam Coutts; Maria-Magdalena Ttitirici

    2014-01-01

    The synthesis of carbon-based, heterogeneous sulphonic catalysts for the production of levulinate esters. Hydrothermal treatment at moderated temperatures was employed to generate highly func-tional carbonaceous materials, referred to as hydrothermal carbons (HTCs), from both glucose, cellulose and rye straw. The products were sulfonated to generate solid acid-catalysts. Characterisa-tion of the as-synthesised materials as well as catalyst activity tests were performed. SEM images indicate the micrometre-sized particles present in both HTCs were largely unaffected by sulfona-tion, although cellulose-derived HTC displayed signs of inadequate hydrolysis. FT-IR spectroscopy and elemental analysis confirmed successful incorporation of sulphonic groups. 13C solid state NMR, in addition to TGA, elucidated the carbons’ structural composition and supported the common-ly-proposed hydrothermal carbonisation mechanism. Finally, the catalysts were tested via levulinic acid-ethanol esterification and gave high conversion and ester-selectivities (>90%).

  13. Electrocoagulation of commercial naphthalene sulfonates: process optimization and assessment of implementation potential.

    Science.gov (United States)

    Olmez-Hanci, Tugba; Kartal, Zeynep; Arslan-Alaton, Idil

    2012-05-30

    The commercially important naphthalene sulfonate K-acid (C(10)H(9)NO(9)S(3); 2-naphthylamine 3,6,8-tri sulfonic acid) was subjected to electrocoagulation employing stainless steel electrodes. An experimental design tool was used to mathematically describe and optimize the single and combined influences of major process variables on K-acid and its organic carbon (COD and TOC) removal efficiencies as well as electrical energy consumption. Current density, followed by treatment time were found to be the parameters affecting process responses most significantly, whereas initial K-acid concentration had the least influence on the electrocoagulation performance. Process economics including sludge generation, electrode consumption, and electrochemical efficiency, as well as organically bound adsorbable halogen formation and toxicity evolution were primarily considered to question the feasibility of K-acid electrocoagulation. Considering process economics and ecotoxicological parameters, process implementation appeared to be encouraging. PMID:22318240

  14. Interfacial assignment of branched-alkyl benzene sulfonates: A molecular simulation

    Science.gov (United States)

    Liu, Zi-Yu; Wei, Ning; Wang, Ce; Zhou, He; Zhang, Lei; Liao, Qi; Zhang, Lu

    2015-11-01

    A molecular dynamics simulation was conducted to analyze orientations of sodium branched-alkyl benzene sulfonates molecules at nonane/water interface, which is helpful to design optimal surfactant structures to achieve ultralow interfacial tension (IFT). Through the two dimensional density profiles, monolayer collapses are found when surfactant concentration continues to increase. Thus the precise scope of monolayer is certain and orientation can be analyzed. Based on the simulated results, we verdict the interfacial assignment of branched-alkyl benzene sulfonates at the oil-water interface, and discuss the effect of hydrophobic tail structure on surfactant assignment. Bigger hydrophobic size can slow the change rate of surfactant occupied area as steric hindrance, and surfactant meta hydrophobic tails have a stronger tendency to stretch to the oil phase below the collapsed concentration. Furthermore, an interfacial model with reference to collapse, increasing steric hindrance and charge repulsive force between interfacial surfactant molecules, responsible for effecting of surfactant concentration and structure has been supposed.

  15. Stabilized sulfonated aromatic polymers by in situ solvothermal cross-linking

    Directory of Open Access Journals (Sweden)

    Maria Luisa eDi Vona

    2014-10-01

    Full Text Available The cross-link reaction via sulfone bridges of sulfonated polyetheretherketone (SPEEK by thermal treatment at 180 °C in presence of dimethylsulfoxide (DMSO is discussed. The modifications of properties subsequent to the cross-linking are presented. The mechanical strength as well as the hydrolytic stability increased with the thermal treatment time, i.e., with the degree of cross-linking. The proton conductivity was determined as function of temperature, IEC, degree of cross-linking and hydration number. The memory effect, which is the membrane ability to remember the water uptake reached at high temperature also at lower temperature, is exploited in order to achieve high values of conductivity. Membranes swelled at 110 °C can reach a conductivity of 0.14 S/cm at 80°C with a hydration number ( of 73.

  16. Sulfonate-based fluorescent probes for imaging hydrogen peroxide in living cells

    Institute of Scientific and Technical Information of China (English)

    XU KeHua; LIU Fen; WANG HuiXia; WANG ShanShan; WANG LuLu; TANG Bo

    2009-01-01

    Based on the mechanism of H2O2-mediated hydrolysis of sulfonates, two fluorescein disulfonates compounds (FS-1 and FS-2) were designed and synthesized as the highly selective and sensitive fluo-rescent probes for imaging H2O2 in living cells. The probes were detected with elemental analysis, IR, 1H NMR and 13C NMR. Upon reaction with H2O2, the probes exhibit strong fluorescence responses and high selectivity for H202 over other reactive oxygen species and some biological compounds. Fur-thermore, the sulfonate-based probes, as novel fluorescent reagents, are cell-permeable and can detect micromolar changes in H202 concentrations in living cells by using confocal microscopy.

  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. Oil-soluble metal containing sulfonated polymers useful as oil additives

    Energy Technology Data Exchange (ETDEWEB)

    Miller, H.N.

    1983-02-08

    This invention relates to oil soluble, metal containing sulfonated polymers useful as additives for lubricating oils or hydrocarbon fuels and which are effective as dispersants. Such polymers of high molecular weight are also useful as viscosityindex improvers for the lubricating oils. The polymeric dispersant additives are ionic polymers which comprise a backbone substantially soluble in the fuel or lubricant, and pendant ionic groups which are sulfonic acid groups neutralized with a metal compound. Polymeric dispersant additives of this type may be made which are also capable of imparting excellent viscosity improvement, varnish inhibition, oxidation inhibition and detergency to the lubricant. These additives may also impart rust preventive properties to the oil or fuel, and as V.I. improvers they can be formed to have particularly good low temperature viscosity effects in lubricating oil.

  19. Mechanically and structurally robust sulfonated block copolymer membranes for water purification applications

    International Nuclear Information System (INIS)

    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. (paper)

  20. Intercalation of Varied Sulfonates into a Layered MOC: Confinement-Caused Tunable Luminescence and Novel Properties.

    Science.gov (United States)

    Wen, Yuehong; Sheng, Tianlu; Zhu, Xiaoquan; Zhang, Hao; Zhuo, Chao; Hu, Shengmin; Cao, Wenhai; Wu, Xintao

    2016-04-01

    The pores/channels of porous 3D metal-organic frameworks (MOFs) have been widely applied to incorporate gas, solvent, or organic molecules. On the contrary, the utilization of the interlamellar void of layered metal-organic complexes (MOCs) remains underappreciated, although it is more flexible and available to accommodate molecules with different sizes. In this work, diverse sulfonates have been intercalated purposely into an identical layered MOC, which constructed various novel intercalation compounds possessing fluorescent, white-light emitting, photochromic, homochiral, or nonlinear optical (NLO) properties. With the help of single-crystal X-ray diffraction, their structures and the mutual interactions between the MOC host and the sulfonate guests were characterized. The properties of the guest molecules were tuned and meanwhile some new performances were generated after confining them into the interlayer region. Such a hybrid approach provides an efficient strategy to design and prepare multifunctional materials. PMID:26919304

  1. A database study of intermolecular NH...O hydrogen bonds for carboxylates, sulfonates and monohydrogen phosphonates

    International Nuclear Information System (INIS)

    A search of the Cambridge Structural Database (CSD, version 5.05, 1993) was performed in order to compare the geometrical features of the hydrogen bonds involving on the one hand amino groups and on the other hand carboxylates, sulfonates or monohydrogen phosponates. Phosphonates were not considered because only four entries containing amino and phosphonate moieities were located in the CSD. The hydroxylic group of monohydrogen phosphonates primarily acts as a hydrogen-bond donor. The three moieties under study show NH..O hydrogen bonds with similar geometrical features. This statistical analysis has focused on the hydrogen-bond distances and angles and on the distributions of the H atoms around the acceptor O atoms of carboxylates, sulfonates or monohydrogen phosphonates. (orig.)

  2. Sulfonation of polyester fabrics by gaseous sulfur oxide activated by UV irradiation

    Science.gov (United States)

    Kordoghli, Bessem; Khiari, Ramzi; Mhenni, Mohamed Farouk; Sakli, Faouzi; Belgacem, Mohamed Naceur

    2012-10-01

    This paper describes an original technique aiming to improve the hydrophilic properties of polyester fibres. In this method, the sulfonation of the aromatic rings is carried out using gaseous sulfur trioxide activated by UV irradiations. Thus, exposing the polyester textile fabric to the UVC light (wavelength around 254 nm) under a stream of sulfur trioxide leads to the fixation of sbnd SO3H groups. The amounts of the fixed sulfonate groups depended on the reaction conditions. Evidence of grafting deduced from the measurements of hygroscopic properties was carried out by contact angle measurement, moisture regain as well as by measuring the rate of retention. SEM and FT-IR analysis, DSC and DTA/TGA thermograms showed that no significant modifications have occurred in the bulk of the treated PET fabrics.

  3. Imidazolium ionic liquid-supported sulfonic acids: Efficient and recyclable catalysts for esterification of benzoic acid

    Institute of Scientific and Technical Information of China (English)

    Yue Qin Cai; Guo Qiang Yu; Chuan Duo Liu; Yuan Yuan Xu; Wei Wang

    2012-01-01

    Several imidazolium ionic liquid (IL)-supported sulfonic acids with different anions,[C3SO3Hmim]HSO4,[C3SO3Hmim]BF4,[C3SO3Hmim]PF6,and [C3SO3Hmim]CF3SO3,were synthesized and applied as catalysts for esterification reaction of benzoic acid.The experimental results indicate that imidazolium IL-supported sulfonic acid containing anion of HSO4- shows the best catalytic activity.Only when less [C3SO3Hmim]HSO4 (0.3 equiv.) applied,was the product obtained with high yield of 97%.Furthermore,the produced esters could be separated by decantation,and the catalyst could be reused after the removal of water.

  4. Sulfonate-based fluorescent probes for imaging hydrogen peroxide in living cells

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Based on the mechanism of H2O2-mediated hydrolysis of sulfonates, two fluorescein disulfonates compounds (FS-1 and FS-2) were designed and synthesized as the highly selective and sensitive fluorescent probes for imaging H2O2 in living cells. The probes were detected with elemental analysis, IR, 1H NMR and 13C NMR. Upon reaction with H2O2, the probes exhibit strong fluorescence responses and high selectivity for H2O2 over other reactive oxygen species and some biological compounds. Furthermore, the sulfonate-based probes, as novel fluorescent reagents, are cell-permeable and can detect micromolar changes in H2O2 concentrations in living cells by using confocal microscopy.

  5. IMMOBILIZATION OF POTENTIALLY BIOACTIVE MOIETIES ONTO POLYETHER WITH POLY(ETHYLENE GLYCOL)-SULFONATE SPACER

    Institute of Scientific and Technical Information of China (English)

    JI Jian; FENG Linxian; QIU Yongxin; YU Xiaojie; YANG Shilin

    1997-01-01

    A new reactive graft copolymer, poly(tetramethylene glycol)-graft-ω-propyl sodium sulfonate-poly(ethylene glycol) (PTMG-g-PEG-CH2CH2CH2SO-3Na+), was synthesized by the cationic polymerization of α-ω-bifunctional PEG macromonomer ((o)CH2-PEG--CH2CH2CH2SO3Na ) and THF. The obtained copolymer exhibits the expected structure as indicated by the result of characterization. Two amino acids (L-arginine, L-tyrosine) were covalently attached to the copolymer after converting the sulfonate group to sulfonyl chloride. So the new reactive graft copolymer (PTMG-g-PEG-CH2CH2CH2SO-3Na+) is expected to be very useful in attachment of potentially bioactive moieties to polymer via a hydrophilic PEG spacer.

  6. Analisis sobre las obligaciones

    OpenAIRE

    Parra Avila, Elliot

    2013-01-01

    Los lenguajes ordinarios presentan dificultades de interpretación cuando son usados para formular y resolver problemas filosoficos. Estos inconvenientes intentaron ser solucionados desde las funciones propositivas (Russell) y los lenguajes artificiales (Carnap). Como respuesta a estas tesis surge la escuela de la filosofia del lenguaje ordinario que sostiene 1) la confianza en el lenguaje claro y siple 2) la ideificacion del abuso del lenguaje como origen de todos los problemas filosoficos 3)...

  7. Las Meninas transmedial

    DEFF Research Database (Denmark)

    Kacunko, Slavko

    2001-01-01

    The art-historical methods of exploring the significance of pictures have often been demonstrated in the contemplation and interpretation of Velázquez’ Las Meniñas (1656, Madrid, Prado; 318 x 276 cm). The painting has been analysed for its relation to the viewer, its luminism, its spatial qualiti...... Velazquez’ in Zeitschrift für Kunstgeschichte 2, 1986 (pp. 165-89)...

  8. Las Violencias contra las Mujeres en una Sociedad en Guerra

    OpenAIRE

    Sánchez Gómez, Olga Amparo

    2008-01-01

    Las violencias contra las mujeres exceden los acontecimientos violentos, y abarcan su producción y reproducción como fenómeno social y discursivo. Los hechos violentos y los discursos sobre la violencia aparecen entrelazados, especialmente si se piensa en papel que juega la cultura patriarcal en el desarrollo, perpetuación y validación de las violencias contra las mujeres. “A las mujeres nos violan, nos asaltan y nos golpean, nos ultrajan, nos humillan, nos deshumanizan, nos manosean, nos ase...

  9. Las TIC y las culturas minoritarias en un mundo global

    OpenAIRE

    Ovide, Evaristo

    2008-01-01

    Las culturas minoritarias, sus lenguas y tradiciones se vuelven más minoritarias y su aliento vital se debilita a medida que la globalización las sitúa dentro de un contexto mucho más amplio. La aparición de las Nuevas Tecnologías (NN.TT.) eInternet como base de las mismas ha supuesto una nueva discriminación entre los que tienen acceso a ellas y los que no. Las culturas minoritarias lo son por haber sido doblegadas por otra dominante y por ello, a menudo padecen males más acuciantes que la p...

  10. Effects of polymer structure on properties of sulfonated polyimide/protic ionic liquid composite membranes for nonhumidified fuel cell applications.

    Science.gov (United States)

    Yasuda, Tomohiro; Nakamura, Shin-ichiro; Honda, Yoshiyuki; Kinugawa, Kei; Lee, Seung-Yul; Watanabe, Masayoshi

    2012-03-01

    To investigate the effects of polymer structure on the properties of composite membranes including a protic ionic liquid, [dema][TfO] (diethylmethylammonium trifluoromethanesulfonate), for nonhumidified fuel cell applications, we synthesized sulfonated polyimides (SPIs) with different structures as matrix polymers, which have different magnitudes of ion-exchange capacities (IECs), different sequence distributions of ionic groups, and positions of sulfonate groups in the main chain or side chain. Despite having similar IECs, multiblock copolymer SPI and random copolymer SPI having sulfonate groups in the side chain exhibit higher ionic conductivity than random copolymer SPI having sulfonate groups in the main chain, indicating that the flexibility of sulfonic acid groups and the sequence distribution of ionic groups greatly affect the ion conduction. Atomic force microscopy observation revealed that the multiblock copolymer SPI forms more developed phase separation than the others. These results indicate that the flexibility of sulfonic acid groups and the connectivity of the ion conduction channel, which greatly depends on the sequence distribution, affect the ion conduction. PMID:22352958

  11. Sulfonation Process and Desalination Effect of Polystyrene/PVDF Semi-Interpenetrating Polymer Network Cation Exchange Membrane

    Directory of Open Access Journals (Sweden)

    Yin-lin Lei

    2014-07-01

    Full Text Available With the classical sulfonation method of polystyrene-based strongly acidic cation exchange resins, polystyrene/polyvinylidene fluoride (PVDF alloy particles were sulfonated to obtain a cation exchange resin, which was then directly thermoformed to prepare a semi-interpenetrating polymer network (semi-IPN cation exchange membrane. The effects of the swelling agent, sulfonation time and temperature and the relative contents of polystyrene and divinylbenzene (DVB in the alloy particles on the feasibility of the membrane formation are discussed. The results indicate that a favorable sulfonation degree above 80% and a suitable ion exchange capacity of 1.5–2.4 mmol/g can be gained, with concentrated sulfuric acid as the sulfonation agent and 1,2-dichloroethane as the swelling agent. The running electrical resistance and desalination effect of the prepared cation exchange membrane were measured in a pilot-scale electrodialyser and not only obviously exceeded a commercial heterogeneous cation exchange membrane, but was also very close to a commercial homogenous membrane. In this way, the authors have combined the classical sulfonation method of polystyrene-based cation exchange resins with the traditional thermoforming manufacturing process of heterogeneous cation exchange membranes, to successfully develop a novel, low-price, but relatively high-performance polystyrene/PVDF cation exchange membrane with the semi-IPN structure.

  12. Three 2D Ag(I)-framework isomers with helical structures controlled by the chirality of camphor-10-sulfonic acid.

    Science.gov (United States)

    Guo, Peng

    2011-02-28

    Three 2D Ag(I)-framework isomers were constructed from enantiopure camphor-10-sulfonic acids or racemic camphor-10-sulfonic acids, together with achiral 4-aminobenzoic acids. In complex 1, (+)-camphor-10-sulfonic acids bridge the single left-handed helices that are made up of Ag ions and 4-aminobenzoic acids, generating a homochiral 2D layer. In such a structure, the interweaving of triple left-handed homohelices was also found. It is worth noting that the helicity of complex 2 could be controlled by the handedness of the camphor-10-sulfonic acid. In complex 2, there are right-handed helical structures, including single right-handed and triple right-handed helical structures connected by (-)-camphor-10-sulfonic acids. For a comparative study, (±)-camphor-10-sulfonic acids were utilized to synthesize complex 3, in which equal numbers of right-handed or left-handed double-helical chains are created. All the complexes were characterized by single-crystal X-ray structure determination, powder X-ray diffraction, IR, TGA and element analysis. Circular dichroism spectra of complexes 1 and 2 were been studied to confirm the fact that enantiopure bridging ligands do not racemize. PMID:21264423

  13. Organic-inorganic crosslinked and hybrid membranes derived from sulfonated poly(arylene ether sulfone)/silica via sol-gel process

    Science.gov (United States)

    Feng, Shaoguang; Shang, Yuming; Wang, Yingzi; Xie, Xiaofeng; Mathur, V. K.; Xu, Jingming

    A series of covalently crosslinkable organic-inorganic hybrid membranes have been prepared from sulfonated poly(arylene ether sulfone) (SPAES) with pendant propenyl moiety and various amounts of vinyl substituted silica via sol-gel process which are then thermally crosslinked in the presence of benzoyl peroxide (BPO) initiator. The obtained membranes are characterized in terms of oxidative stability, thermal property, ion exchange capacity (IEC), water uptake, swelling ratio in methanol aqueous solution, proton conductivity, and methanol permeability coefficient. The results indicate that the oxidative stability and thermal stability of the hybrid membranes are improved. Moreover, introduction of silica reduces the water uptake and methanol swelling of membranes. The swelling ratio of membranes in 2 mol L -1 methanol aqueous solution at 80 °C slowly decreases from 26 to 19% with the increase of SiO 2 content from 0 to 12 wt.%. Furthermore, with the increase in silica content, the methanol permeability coefficient of the hybrid membranes decreases at first and then increases. When the silica content reaches 8 wt.%, the methanol permeability coefficient is at the minimum of 6.02 × 10 -7 cm 2 s -1, a 2.64-fold decrease compared with that of the pristine SPAES membrane. Moreover, the proton conductivity is found to be at about 95% of that of pristine polymer at that silica content.

  14. Computational and experimental investigations of one-step conversion of poly(carbonate)s into value-added poly(aryl ether sulfone)s.

    Science.gov (United States)

    Jones, Gavin O; Yuen, Alexander; Wojtecki, Rudy J; Hedrick, James L; García, Jeannette M

    2016-07-12

    It is estimated that ∼2.7 million tons poly(carbonate)s (PCs) are produced annually worldwide. In 2008, retailers pulled products from store shelves after reports of bisphenol A (BPA) leaching from baby bottles, reusable drink bottles, and other retail products. Since PCs are not typically recycled, a need for the repurposing of the PC waste has arisen. We report the one-step synthesis of poly(aryl ether sulfone)s (PSUs) from the depolymerization of PCs and in situ polycondensation with bis(aryl fluorides) in the presence of carbonate salts. PSUs are high-performance engineering thermoplastics that are commonly used for reverse osmosis and water purification membranes, medical equipment, as well as high temperature applications. PSUs generated through this cascade approach were isolated in high purity and yield with the expected thermal properties and represent a procedure for direct conversion of one class of polymer to another in a single step. Computational investigations performed with density functional theory predict that the carbonate salt plays two important catalytic roles in this reaction: it decomposes the PCs by nucleophilic attack, and in the subsequent polyether formation process, it promotes the reaction of phenolate dimers formed in situ with the aryl fluorides present. We envision repurposing poly(BPA carbonate) for the production of value-added polymers.

  15. Effect of degree of sulfonation and casting solvent on sulfonated poly(ether ether ketone) membrane for vanadium redox flow battery

    Science.gov (United States)

    Xi, Jingyu; Li, Zhaohua; Yu, Lihong; Yin, Bibo; Wang, Lei; Liu, Le; Qiu, Xinping; Chen, Liquan

    2015-07-01

    The properties of sulfonated poly(ether ether ketone) (SPEEK) membranes with various degree of sulfonation (DS) and casting solvent are investigated for vanadium redox flow battery (VRFB). The optimum DS of SPEEK membrane is firstly confirmed by various characterizations such as physicochemical properties, ion selectivity, and VRFB single-cell performance. Subsequently the optimum casting solvent is selected for the optimum DS SPEEK membrane within N,N‧-dimethylformamide (DMF), N,N‧-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), and dimethylsulfoxide (DMSO). The different performance of SPEEK membranes prepared with various casting solvents can be attributed to the different interaction between solvent and -SO3H group of SPEEK. In the VRFB single-cell test, the optimum SPEEK membrane with DS of 67% and casting solvent of DMF (S67-DMF membrane) exhibits higher VRFB efficiencies and better cycle-life performance at 80 mA cm-2. The investigation of various DS and casting solvent will be effective guidance on the selection and modification of SPEEK membrane towards VRFB application.

  16. Sulfonated poly(ether sulfone) (SPES)/boron phosphate (BPO{sub 4}) composite membranes for high-temperature proton-exchange membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Sheng [Faculty of Chemistry and Material Science, Xiaogan University, Xiaogan, Hubei 432100 (China); Ministry of Education, Key Laboratory for the Green, Preparation and Application of Functional Materials, Institute of Composite Materials, Faculty of Materials Science and Engineering, Hubei University, Wuhan 430062 (China); Gong, Chunli [Faculty of Chemistry and Material Science, Xiaogan University, Xiaogan, Hubei 432100 (China); Tsen, Wen-Chin; Shu, Yao-Chi [Department of Polymer Materials, Vanung University, Tao-Yuan, Taiwan 32045 (China); Tsai, Fang-Chang [Ministry of Education, Key Laboratory for the Green, Preparation and Application of Functional Materials, Institute of Composite Materials, Faculty of Materials Science and Engineering, Hubei University, Wuhan 430062 (China)

    2009-11-15

    A new series of sulfonated poly(ether sulfone) (SPES)/boron phosphate (BPO{sub 4}) composite membranes for proton-exchange membrane fuel cells (PEMFCs) applications, with a BPO{sub 4} content up to 40 wt%, were prepared by a sol-gel method using tripropylborate and phosphoric acid as precursors. Compared to a pure SPES membrane, BPO{sub 4} doping in the membranes led to a higher thermal stability and glass-transition temperature (T{sub g}) as revealed by TGA-FTIR, DSC and DMTA. Water uptake and oxidative stability were significantly increased by increasing the content of BPO{sub 4}. At both operating temperature conditions, namely 20 C and 100 C, the tensile strength of all the composite membranes were lower than that of the SPES membrane. However, even when the content of BPO{sub 4} was as high as 30%, the composite membrane still possessed strength similar to the Nafion 112 membrane. SEM-EDX indicated that the BPO{sub 4} particles were uniformly embedded throughout the SPES matrix, which may facilitate proton transport. Proton conductivities increased from 0.0065 to 0.022 S cm{sup -1} at room temperature as BPO{sub 4} increased from 0 to 40%. The conductivities also increased with the temperature. The SPES/BPO{sub 4} composite membrane is a promising candidate for PEMFCs applications, especially at higher temperatures. (author)

  17. Organic-inorganic crosslinked and hybrid membranes derived from sulfonated poly(arylene ether sulfone)/silica via sol-gel process

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Shaoguang; Shang, Yuming; Wang, Yingzi; Xie, Xiaofeng; Xu, Jingming [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Mathur, V.K. [Department of Chemical Engineering, University of New Hampshire, NH 03824 (United States)

    2010-05-01

    A series of covalently crosslinkable organic-inorganic hybrid membranes have been prepared from sulfonated poly(arylene ether sulfone) (SPAES) with pendant propenyl moiety and various amounts of vinyl substituted silica via sol-gel process which are then thermally crosslinked in the presence of benzoyl peroxide (BPO) initiator. The obtained membranes are characterized in terms of oxidative stability, thermal property, ion exchange capacity (IEC), water uptake, swelling ratio in methanol aqueous solution, proton conductivity, and methanol permeability coefficient. The results indicate that the oxidative stability and thermal stability of the hybrid membranes are improved. Moreover, introduction of silica reduces the water uptake and methanol swelling of membranes. The swelling ratio of membranes in 2 mol L{sup -1} methanol aqueous solution at 80 C slowly decreases from 26 to 19% with the increase of SiO{sub 2} content from 0 to 12 wt.%. Furthermore, with the increase in silica content, the methanol permeability coefficient of the hybrid membranes decreases at first and then increases. When the silica content reaches 8 wt.%, the methanol permeability coefficient is at the minimum of 6.02 x 10{sup -7} cm{sup 2} s{sup -1}, a 2.64-fold decrease compared with that of the pristine SPAES membrane. Moreover, the proton conductivity is found to be at about 95% of that of pristine polymer at that silica content. (author)

  18. Computational and experimental investigations of one-step conversion of poly(carbonate)s into value-added poly(aryl ether sulfone)s.

    Science.gov (United States)

    Jones, Gavin O; Yuen, Alexander; Wojtecki, Rudy J; Hedrick, James L; García, Jeannette M

    2016-07-12

    It is estimated that ∼2.7 million tons poly(carbonate)s (PCs) are produced annually worldwide. In 2008, retailers pulled products from store shelves after reports of bisphenol A (BPA) leaching from baby bottles, reusable drink bottles, and other retail products. Since PCs are not typically recycled, a need for the repurposing of the PC waste has arisen. We report the one-step synthesis of poly(aryl ether sulfone)s (PSUs) from the depolymerization of PCs and in situ polycondensation with bis(aryl fluorides) in the presence of carbonate salts. PSUs are high-performance engineering thermoplastics that are commonly used for reverse osmosis and water purification membranes, medical equipment, as well as high temperature applications. PSUs generated through this cascade approach were isolated in high purity and yield with the expected thermal properties and represent a procedure for direct conversion of one class of polymer to another in a single step. Computational investigations performed with density functional theory predict that the carbonate salt plays two important catalytic roles in this reaction: it decomposes the PCs by nucleophilic attack, and in the subsequent polyether formation process, it promotes the reaction of phenolate dimers formed in situ with the aryl fluorides present. We envision repurposing poly(BPA carbonate) for the production of value-added polymers. PMID:27354514

  19. Facile Synthesis of Effcient and Selective Ruthenium Olefin Metathesis Catalysts with Sulfonate and Phosphate Ligands

    OpenAIRE

    Teo, Peili; Grubbs, Robert H.

    2010-01-01

    A series of novel, air-stable ruthenium NHC catalysts with sulfonate and phosphate anions have been prepared easily in one pot at high yields using commercially available precursors. The catalysts were found to be effective for ring-opening metathesis polymerization, ring-closing metathesis, and cross-metathesis. The catalysts showed higher cis-selectivity in olefin cross-metathesis reactions as compared to earlier known ruthenium-based olefin metathesis catalysts, with allylbenzene and cis-1...

  20. The solvation and ion condensation properties for sulfonated polyelectrolytes in different solvents : a computational study

    OpenAIRE

    Smiatek, Jens; Wohlfarth, Andreas; Holm, Christian

    2014-01-01

    In contrast to the broad knowledge about aqueous polyelectrolyte solutions, less is known about the properties in aprotic and apolar solvents. We therefore investigate the behavior of sulfonated polyelectrolytes in sodium form in the presence of different solvents via all-atom molecular dynamics simulations. The results clearly reveal strong variations in ion condensation constants and polyelectrolyte conformations for different solvents like water, dimethyl sulfoxide (DMSO) and chloroform. T...

  1. Sonochemical Degradation of Perfluorooctane Sulfonate (PFOS) and Perfluorooctanoate (PFOA) in Groundwater: Kinetic Effects of Matrix Inorganics

    OpenAIRE

    Cheng, Jie; vecitis, Chad D.; Park, Hyunwoong; Mader, Brian T.; Hoffmann, Michael R.

    2010-01-01

    Ultrasonic irradiation has been shown to effectively degrade perfluorinated chemicals (PFCs) such as perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) in aqueous solution. Reduced PFC sonochemical degradation rates in organic-rich groundwater taken from beneath a landfill, however, testify to the negative kinetic effects of the organic groundwater constituents. In this study, the PFOX (X = S or A) sonochemical degradation rates in a groundwater sample with organic concentrations ...

  2. Small-angle neutron scattering studies of sodium butyl benzene sulfonate aggregates in aqueous solution

    Indian Academy of Sciences (India)

    O R Pal; V G Gaikar; J V Joshi; P S Goyal; V K Aswal

    2004-08-01

    The aggregation behaviour of a hydrotrope, sodium -butyl benzene sulfonate (Na-NBBS), in aqueous solutions is investigated by small-angle neutron scattering (SANS). Nearly ellipsoidal aggregates of Na-NBBS at concentrations well above its minimum hydrotrope concentration were detected by SANS. The hydrotrope seems to form self-assemblies with aggregation number of 36–40 with a substantial charge on the aggregate. This aggregation number is weakly affected by the hydrotrope concentration.

  3. Validation and optimization of experimental colitis induction in rats using 2, 4, 6-trinitrobenzene sulfonic acid

    OpenAIRE

    Motavallian-Naeini, A.; Andalib, S.; M Rabbani; Mahzouni, P.; Afsharipour, M.; Minaiyan, M.

    2012-01-01

    Trinitrobenzene sulfonic acid (TNBS)-induced colitis is one of the most common methods for studying inflammatory bowel disease in animal models. Several factors may, however, affect its reproducibility, rate of animal mortality, and macroscopic and histopathological outcomes. Our aim was to validate the main contributing factors to this method and compare the effects of different reference drugs upon remission of resultant colon injuries. TNBS was dissolved in 0.25 ml of ethanol (50% v/v) and...

  4. SYNTHESIS AND CHARACTERIZATION O F SODIUM METHYL ESTER SULFONATE FOR CHEMICALLY-ENHANCED OIL RECOVERY

    OpenAIRE

    Babu, K.; N. K. Maurya; Mandal, A.; Saxena, V. K.

    2015-01-01

    AbstractAttention has been given to reduce the cost of surfactant by using castor oil as an alternative natural source of feedstock. A new surfactant, sodium methyl ester sulfonate (SMES) was synthesised using ricinoleic acid methyl ester, which is obtained from castor oil, for enhanced oil recovery in petroleum industries. The performance of SMES was studied by measuring the surface tension with and without sodium chloride and its thermal stability at reservoir temperature. SMES exhibited go...

  5. The Effect of Perfluorooctane Sulfonate, Exposure Time, and Chemical Mixtures on Methanogenic Community Structure and Function

    OpenAIRE

    McNamara, Patrick J.; LaPara, Timothy M.; Novak, Paige J

    2015-01-01

    A plethora of organic micropollutant mixtures are found in untreated municipal wastewater. Anaerobic digesters receive large loadings of hydrophobic micropollutants that sorb to wastewater biosolids. Despite micropollutants being pervasive as mixtures, little research is available to explain the impact that mixtures of compounds, as well as exposure time, have on microbial communities in anaerobic digesters. Perfluorooctane sulfonate (PFOS) was added to anaerobic enrichment cultures in both s...

  6. Sulfonated graphenes catalyzed synthesis of expanded porphyrins and their supramolecular interactions with pristine graphene

    Indian Academy of Sciences (India)

    Sweta Mishra; Smriti Arora; Ritika Nagpal; Shive Murat Singh Chauhan

    2014-11-01

    A newer synthesis of sulfonic acid functionalized graphenes have been developed, which have been characterized, examined as heterogeneous solid acid carbocatalyst in the synthesis of selected expanded porphyrins in different reaction conditions. This environment-friendly catalyst avoids the use of toxic catalysts and enhances the yields of porphyrinoids. The non-covalent interaction of porphyrinoids has also been studied with exfoliated graphene solution in organic solvents by UV-Visible and fluorescence spectroscopy.

  7. Exposure to Perfluorooctane Sulfonate In Utero Reduces Testosterone Production in Rat Fetal Leydig Cells

    OpenAIRE

    Binghai Zhao; Li Li; Jieting Liu; Hongzhi Li; Chunlei Zhang; Pengfei Han; Yufei Zhang; Xiaohuan Yuan; Ren Shan Ge; Yanhui Chu

    2014-01-01

    BACKGROUND: Perfluorooctane sulfonate (PFOS) is a synthetic material that has been widely used in industrial applications for decades. Exposure to PFOS has been associated with decreased adult testosterone level, and Leydig cell impairment during the time of adulthood. However, little is known about PFOS effects in utero on fetal Leydig cells (FLC). METHODS AND RESULTS: The present study investigated effects of PFOS on FLC function. Pregnant Sprague Dawley female rats received vehicle (0.05% ...

  8. Refugiados de las pandillas centroamericanas

    OpenAIRE

    Kennedy, Elizabeth G.

    2013-01-01

    El Salvador, Guatemala y Honduras se encuentran entre las naciones más frágiles del mundo, sin embargo, son ampliamente ignoradas por las agencias de refugiados que subestiman los abusos y poderes de control de las organizaciones criminales transnacionales, mientras sobrestiman la capacidad y voluntad de los gobiernos nacionales de proteger a sus ciudadanos.

  9. Las telenovelas juveniles mexicanas y las adolescentas obesas

    Directory of Open Access Journals (Sweden)

    Tania Meza

    2006-01-01

    Full Text Available Esta investigación analiza la opresión por cuerpo (obesidad a la que las mujeres son sometidas dentro del sistema patriarcal durante la adolescencia, específicamente a través de la representación televisiva que de las jóvenes gordas se hace en la telenovela juvenil mexicana. Los enormes niveles de audiencia que poseen las telenovelas en nuestro país hace indispensable, para los estudios de género desde las ciencias dela comunicación, estudiar el papel de las mujeres en dichas teleseries. En este análisis se pretende mostrar la triple marginación a la que son sometidas las adolescentes obesas en las telenovelas juveniles mexicanas: por ser mujeres, por ser jóvenes y por ser gordas.

  10. Nanocasting Design and Spatially Selective Sulfonation of Polystyrene-Based Polymer Networks as Solid Acid Catalysts.

    Science.gov (United States)

    Richter, Felix H; Sahraoui, Laila; Schüth, Ferdi

    2016-09-12

    Nanocasting is a general and widely applied method in the generation of porous materials during which a sacrificial solid template is used as a mold on the nanoscale. Ideally, the resulting structure is the inverse of the template. However, replication is not always as direct as anticipated, so the influences of the degree of pore filling and of potential restructuring processes after removal of the template need to be considered. These apparent limitations give rise to opportunities in the synthesis of poly(styrene-co-divinylbenzene) (PSD) polymer networks of widely varying porosities (BET surface area=63-562 m(2)  g(-1) ; Vtot =0.18-1.05 cm(3)  g(-1) ) by applying a single synthesis methodology. In addition, spatially selective sulfonation on the nanoscale seems possible. Together, nanocasting and sulfonation enable rational catalyst design. The highly porous nanocast and predominantly surface-sulfonated PSD networks approach the activity of the corresponding molecular catalyst, para-toluenesulfonic acid, and exceed those of commercial ion-exchange polymers in the depolymerization of macromolecular inulin.

  11. The Effects of Sulfonated Poly(ether ether ketone Ion Exchange Preparation Conditions on Membrane Properties

    Directory of Open Access Journals (Sweden)

    Rebecca S. L. Yee

    2013-08-01

    Full Text Available A low cost cation exchange membrane to be used in a specific bioelectrochemical system has been developed using poly(ether ether ketone (PEEK. This material is presented as an alternative to current commercial ion exchange membranes that have been primarily designed for fuel cell applications. To increase the hydrophilicity and ion transport of the PEEK material, charged groups are introduced through sulfonation. The effect of sulfonation and casting conditions on membrane performance has been systematically determined by producing a series of membranes synthesized over an array of reaction and casting conditions. Optimal reaction and casting conditions for producing SPEEK ion exchange membranes with appropriate performance characteristics have been established by this uniquely systematic experimental series. Membrane materials were characterized by ion exchange capacity, water uptake, swelling, potential difference and NMR analysis. Testing this extensive membranes series established that the most appropriate sulfonation conditions were 60 °C for 6 h. For mechanical stability and ease of handling, SPEEK membranes cast from solvent casting concentrations of 15%–25% with a resulting thickness of 30–50 µm were also found to be most suitable from the series of tested casting conditions. Drying conditions did not have any apparent impact on the measured parameters in this study. The conductivity of SPEEK membranes was found to be in the range of 10−3 S cm−1, which is suitable for use as a low cost membrane in the intended bioelectrochemical systems.

  12. Efficient and selective adsorption of multi-metal ions using sulfonated cellulose as adsorbent.

    Science.gov (United States)

    Dong, Cuihua; Zhang, Fulong; Pang, Zhiqiang; Yang, Guihua

    2016-10-20

    Contamination of heavy metal in wastewater has caused great concerns on human life and health. Developing an efficient material to eliminate the heavy metal ions has been a popular topic in recent years. In this work, sulfonated cellulose (SC) was explored as efficient adsorbent for metal ions in solution. Thermo gravimetric analyzer (TGA), X-ray diffraction (XRD) and Fourier-transform infrared spectrometer (FTIR) first analyzed the characterizations of SC. Subsequently, effects of solution pH, adsorbent loading, temperature and initial metal ion concentration on adsorption performance were investigated. The results showed that sulfonated modification of cellulose could decrease the crystallinity and thermostability of cellulose. Due to its excellent performance of adsorption to metal ions, SC could reach adsorption equilibrium status within as short as 2min. In multi-component solution, SC can orderly removes Fe(3+), Pb(2+) and Cu(2+) with excellent selectivity and high efficiency. In addition, SC is a kind of green and renewable adsorbent because it can be easily regenerated by treatment with acid or chelating liquors. The mechanism study shows that the sulfonic group play a major role in the adsorption process. PMID:27474562

  13. Sulfonic acid heterogeneous catalysts for dehydration of C6-monosaccharides to 5-hydroxymethylfurfural in dimethyl sulfoxide

    Institute of Scientific and Technical Information of China (English)

    Gabriel Morales; Juan A.Melero; Marta Paniagua; Jose Iglesias; Blanca Hernández; María Sanz

    2014-01-01

    Sulfonic acid-functionalized heterogeneous catalysts have been evaluated in the catalytic dehydra-tion of C6 monosaccharides into 5-hydroxymethylfurfural (HMF) using dimethyl sulfoxide (DMSO) as solvent. Sulfonic commercial resin Amberlyst-70 was the most active catalyst, which was as-cribed to its higher concentration of sulfonic acid sites as compared with the other catalysts, and it gave 93 mol%yield of HMF from fructose in 1 h. With glucose as the starting material, which is a much more difficult reaction, the reaction conditions (time, temperature, and catalyst loading) were optimized for Amberlyst-70 by a response surface methodology, which gave a maximum HMF yield of 33 mol%at 147°C with 23 wt%catalyst loading based on glucose and 24 h reaction time. DMSO promotes the dehydration of glucose into anhydroglucose, which acts as a reservoir of the substrate to facilitate the production of HMF by reducing side reactions. Catalyst reuse without a regeneration treatment showed a gradual but not very significant decay in catalytic activity.

  14. Sulfonated graphene nanosheets as a superb adsorbent for various environmental pollutants in water.

    Science.gov (United States)

    Shen, Yi; Chen, Baoliang

    2015-06-16

    Graphene nanosheets, as a novel nanoadsorbent, can be further modified to optimize the adsorption capability for various pollutants. To overcome the structural limits of graphene (aggregation) and graphene oxide (hydrophilic surface) in water, sulfonated graphene (GS) was prepared by diazotization reaction using sulfanilic acid. It was demonstrated that GS not only recovered a relatively complete sp(2)-hybridized plane with high affinity for aromatic pollutants but also had sulfonic acid groups and partial original oxygen-containing groups that powerfully attracted positively charged pollutants. The saturated adsorption capacities of GS were 400 mg/g for phenanthrene, 906 mg/g for methylene blue and 58 mg/g for Cd(2+), which were much higher than the corresponding values for reduced graphene oxide and graphene oxide. GS as a graphene-based adsorbent exhibits fast adsorption kinetic rate and superior adsorption capacity toward various pollutants, which mainly thanks to the multiple adsorption sites in GS including the conjugate π region sites and the functional group sites. Moreover, the sulfonic acid groups endow GS with the good dispersibility and single or few nanosheets which guarantee the adsorption processes. It is great potential to expose the adsorption sites of graphene nanosheets for pollutants in water by regulating their microstructures, surface properties and water dispersion.

  15. QENS investigation of proton confined motions in hydrated perfluorinated sulfonic membranes and self-assembled surfactants

    Directory of Open Access Journals (Sweden)

    Berrod Quentin

    2015-01-01

    Full Text Available We report on QuasiElastic Neutron Scattering (QENS investigations of the dynamics of protons and water molecules confined in nanostructured perfluorinated sulfonic acid (PFSA materials, namely a commercial Aquivion membrane and the perfluorooctane sulfonic acid (PFOS surfactant. The former is used as electrolyte in low-temperature fuel cells, while the latter forms mesomorphous self-assembled phases in water. The dynamics was investigated as a function of the hydration level, in a wide time range by combining time-of-flight and backscattering incoherent QENS experiments. Analysis of the quasielastic broadening revealed for both systems the existence of localized translational diffusive motions, fast rotational motions and slow hopping of protons in the vicinity of the sulfonic charges. The characteristic times and diffusion coefficients have been found to exhibit a very similar behaviour in both membrane and surfactant structures. Our study provides a comprehensive picture of the proton motion mechanisms and the dynamics of confined water in model and real PFSA nanostructures.

  16. Blends of a Polymer of Intrinsic Microporosity and Partially Sulfonated Polyphenylenesulfone for Gas Separation.

    Science.gov (United States)

    Yong, Wai Fen; Lee, Zhi Kang; Chung, Tai-Shung; Weber, Martin; Staudt, Claudia; Maletzko, Christian

    2016-08-01

    Polyphenylenesulfone (PPSU) and sulfonated polyphenylenesulfone (sPPSU) are widely used for liquid separations in the medical and food industries. However, their potential applications for gas separation have not been studied extensively owing to their low intrinsic gas permeability. We report here for the first time that blending with sPPSU can significantly improve the gas separation performance of highly permeable polymers of intrinsic microporosity (PIMs), specifically PIM-1, because of the strong molecular interactions of the sulfonic acid groups of sPPSU with CO2 and O2 . In addition, a novel co-solvent system has been discovered to overcome the immiscibility of these polymers. The presence of a higher degree of sulfonation in sPPSU results in better gas separation performance of the blend membranes close to or above the Robeson upper bound lines for O2 /N2 , CO2 /N2 and CO2 /CH4 separations. Interestingly, the blend membranes have comparable gas selectivity to sPPSU even though their sPPSU content is only 5-20 wt %. Moreover, they also display improved anti-plasticization properties up to 30 atm (3 MPa) using a binary CO2 /CH4 feed gas. The newly developed PIM-1/sPPSU membranes are potential candidates for air separation, natural gas separation, and CO2 capture. PMID:27332951

  17. Colorful Polyelectrolytes: An Atom Transfer Radical Polymerization Route to Fluorescent Polystyrene Sulfonate.

    Science.gov (United States)

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

    2016-03-01

    A labeled green fluorescent polystyrene sulfonate (LNaPSS) has been synthesized using atom transfer radical polymerization of a styrene sulfonate monomer with a fluorescent co-monomer, fluorescein thiocyanate-vinyl aniline. As a result this 100 % sulfonated polymer contains no hydrophobic patches along the chain backbone besides the fluorescent marker itself. The concentration of the fluorescent monomer was kept low to maintain the characteristic properties of the anionic polyelectrolyte, LNaPSS. ATRP conditions facilitated the production of polymers spanning a range of molecular weights from 35,000 to 175,000 in gram-scale batches with polydispersity indices of 1.01-1.24. Molecular weight increased with the monomer to initiator ratio. Gel permeation chromatography results show a unimodal distribution, and the polymer structure was also confirmed by (1)H NMR and FT-IR spectroscopy. Fluorescence spectroscopy confirmed covalent bonding of fluorescein isothiocyanate to the polymer, indicating that the polymer is suitable as a probe in fluorescence microscopy. To demonstrate this ability, the polymer was used to locate structural features in salt crystals formed during drying, as in the evaporation of sea mist. A second application to probe diffusion studies is also demonstrated. PMID:26745991

  18. Properties of Polymer Electrolyte Membranes Prepared by Blending of Sulfonated Polystyrene-Lignosulfonate

    Directory of Open Access Journals (Sweden)

    Siang Tandi Gonggo

    2012-11-01

    Full Text Available Electrolyte polymer membrane widely used in PEMFC and DMFC is a perfluorosulfonated membrane such as Nafion. This membrane material exhibits good chemical stability and proton conductivity, but it is very expensive and difficult to recycle. It has high cross-over methanol in DMFC that causes the decrease efficiency and performance of fuel cell, so that the electrolyte polymer membrane with low cross-over methanol has been needed to substitute Nafion membrane. One of the materials used as a polymer electrolyte membrane is polyblends of a sulfonated polystyrene-lignosulfonate (SPS-LS. These polyblends have been prepared by casting polymer solution and characterized as a polyelectrolyte membrane for DMFC. SPS was prepared by sulfonation of polystyrene with acetyl sulfate used as a sulfonating agent. The membranes of SPS-LS were characterized by analysis of functional groups, mechanical properties, and methanol permeability. The maximum mechanical properties of the SPS-LS membrane were observed in LS ratio of 7.5%. However, the methanol permeability of membrane increases as the increase of LS ratio in SPS-LS membranes. The properties of membranes, especially the mechanical property and methanol permeability close to that of Nafion® 117 membrane, so the SPS-LS membrane is highly potential used as the electrolyte membrane for direct methanol fuel cell.

  19. A polyvinyl alcohol/p-sulfonate phenolic resin composite proton conducting membrane

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Chien-Shun; Lin, Fan-Yen; Chu, Peter P. [Deparment of Chemistry, National Central University, Chung-Li 32054 (Taiwan); Chen, Chih-Yuan [Material Research Laboratory, Industrial Technology Research Institute (ITRI), Hsin-Chu (Taiwan)

    2006-10-06

    Membranes composed of poly(vinyl alcohol) (PVA) and a proton source polymer, sulfonated phenolic resin (s-Ph) displayed good proton conductivity of the order of 10{sup -2}Scm{sup -1} at ambient temperatures. Upon cross-linking above 110{sup o}C, covalent links between the sulfonate groups of the phenolic resin and the hydroxyl groups of the PVA were established. Although this sacrificed certain sulfonate groups, the conductivity value was still preserved at the 10{sup -2}Scm{sup -1} level. In sharp contrast to Nafion, the current membrane (both before and after cross-linking) was also effective in reducing the methanol uptake where the swelling ratio decreased with increase of methanol concentration. Although both the methanol permeation and the proton conductivity were lower compared to Nafion, the conductivity/permeability ratio of 0.97 for the PVA/s-Ph is higher than that determined for Nafion. The results suggested the effectiveness of proton transport in the polymer-complex structure and the possibility that a high proton conductivity can be realized with less water. (author)

  20. Preparation and electrochemical characteristic of porous NiO supported by sulfonated graphene for supercapacitors

    International Nuclear Information System (INIS)

    NiO/sulfonated graphene(NiO/SGN) composites were fabricated under the assistance of urea as supercapacitor materials. The composites as prepared possess the leaf vein-like morphology, forming the porous structure that benefits the enhancement of pseudocapacitive performance. Moreover, the introduction of sulfonated graphene contributes to the surface hydroxylation of NiO, which may increase electrochemically active sites on the surface of NiO. The electrochemical measurements demonstrate that specific capacitances of NiO, NiO/thermally reduced graphene(NiO/TRG) and NiO/SGN are 200, 261 and 307 F g−1 at a current density of 5.0 A g−1 respectively, suggesting that the significant improvement of pseudocapacitive performance for NiO/SGN could be expected. The results from electrochemical impedance spectroscopy(EIS) demonstrate that sulfonated graphene can not only provide electron transport channels for its composites similar to thermally reduced graphene, but also benefit the electrolyte penetration in the composites compared with thermally reduced graphene

  1. Synthesis of Petroleum Sulfonate Surfactant with Ultra-Low Interfacial Tension in Rotating Packed Bed Reactor

    Institute of Scientific and Technical Information of China (English)

    Weng Zhan; Zhang Pengyuan; Chu Guangwen; Zou Haikui; Jimmy Yun; Chen Jianfeng

    2015-01-01

    Petroleum sulfonate is one of the most important surfactants used in surfactant lfooding for enhanced oil recov-ery, which is mainly obtained by treating high-boiling petroleum fractions in a stirred tank reactor (STR) or in a falling-iflm reactor (FFR). The synthesis of petroleum sulfonate with ultra-low interfacial tension from viscous petroleum fractions was carried out in a rotating packed bed (RPB) reactor using dilute liquid sulfur trioxide as the sulfonating agent in this study. The effects of various experimental conditions on components content and oil-water interfacial tension (IFT) were investigated. Under the optimum conditions, the active matter content could reach up to 50.3% and the IFT could be equal to 4.7×10−3 mN/m. Compared with the traditional reactor, the active matter content is by 14.12% higher in the RPB as compared to that obtained in the STR. The uneven change of the test oil droplets during the IFT measurement was also dis-cussed. The increase of heavy components content not only can eliminate the contraction phenomenon, but also can reduce the IFT to a minimum. This can be conducive to explaining the reason for producing IFT and the preparation of proper for-mulations for practical application.

  2. Preparation of low flow-resistant methacrylate-based monolithic stationary phases of different hydrophobicity and the application to rapid reversed-phase liquid chromatographic separation of alkylbenzenes at high flow rate and elevated temperature.

    Science.gov (United States)

    Ueki, Yuji; Umemura, Tomonari; Iwashita, Yoshikazu; Odake, Tamao; Haraguchi, Hiroki; Tsunoda, Kin-ichi

    2006-02-17

    Low flow-resistant alkyl methacrylate-based monolithic stationary phases of different hydrophobicity were constructed for reversed-phase capillary liquid chromatography by thermally initiated radical polymerization of respective methacrylate ester monomer with different alkyl chain (C2, C4, C6, C12, C18) and ethylene glycol dimethacrylate (EDMA) in a 250 microm i.d. fused silica capillary. The hydrophobicity was basically controlled by changing the length and/or the density of the alkyl-chain, while the composition and the ratio of porogenic solvent were adjusted to obtain highly permeable rigid monoliths with adequate column efficiency. Among the prepared monolithic stationary phases, C18-methacrylate monoliths polymerized from a binary porogenic solvent of isoamyl alcohol and 1,4-buthandiol exhibited the most promising performance in terms of hydraulic resistance and column efficiency. The pressure drops of 20-cm long monolithic columns were below approximately 0.4 MPa at a normal linear velocity of 1mm/s (a flow rate of 3 microL/min), and the numbers of theoretical plates for alkylbenzenes mostly exceeded 3000 plates/20 cm. The produced monolithic columns had good mechanical strength for high pressure and temperature, and could be properly operated even at a temperature of 80 degrees C and at a pressure of at least 33 MPa. At 80 degrees C, the theoretical plate numbers reached 6000 plates/20 cm because of the enhanced mass transfer. Due to the novel hydraulic resistance and mechanical strength, the separation time could be reduced 120-fold simply by raising the flow rate and column temperature.

  3. Las marcas propias en Colombia

    Directory of Open Access Journals (Sweden)

    Carlos Felipe Payán Rodríguez

    2013-11-01

    Full Text Available El artículo analiza la situación actual de las marcas propias en Colombia, teniendo en cuenta su creciente auge al interior de las grandes superficies. Mediante este tipo de marcas el mismo distribuidor vende productos y servicios con su nombre o recurriendo a una marca de su propiedad, compitiendo con las marcas ya posicionadas en el mercado de los fabricantes. El texto se articula, primero, en una contextualización con base en doctrina comparada respecto de las marcas propias. Luego, se aplican las reglas de dichos conceptos doctrinales a la situación actual colombiana. Por último, se plantean dos problemas jurídicos respecto de las marcas propias, uno, analizado desde la propiedad industrial, y el otro, desde las reglas del Estatuto del Consumidor.

  4. Las narcodemocracias andinas

    Directory of Open Access Journals (Sweden)

    Olivier DABÈNE

    2009-11-01

    Full Text Available RESUMEN: Los países de América Latina están afectados en diferentes aspectos por el tráfico de drogas. En especial, en los países andinos, esta actividad ha condicionado de manera decisiva el tipo de régimen democrático iniciado en algún caso en la década de 1980, como Perú o Bolivia, o el régimen colombiano. El autor califica a estos regímenes como narcodemocracias por los efectos del tráfico de drogas no sólo en el orden social y económico, que analiza de forma profunda, sino por la politización del narcotráfico. Las respuestas de las democracias han sido bien distintas en los tres casos analizados, afectando, sin embargo, en todos ellos, a la gobernabilidad de las mismas y a su legitimidad.ABSTRACT: Latin American countries are affected by narcotrafico in different aspects. Particularly, in Andean countries, this activity has deeply conditioned the type of democratic regime installed in some cases in the eighties, as Perou and Bolivia, or the colombian regimen. The author characterizes these regimes as narcodemocracias by effects of narcotrafico in them, not only in social and economic arenas, but also by the politization of narcotrafico. Responses of democracies have been very different in these cases analyzed in the article. Nevertheless, in all of them, governability and legitmity of democracy are affected.

  5. Las computadoras inteligentes

    OpenAIRE

    Lara-Rojo, Fernando

    1991-01-01

    Se habla de la inteligencia artificial como un campo de la ciencia de computación que tiene por objetivo construir computadoras capaces de hacerse cargo de tareas para cuya realización se supone que es necesario contar con cierto grado de “inteligencia”. Se explora el panorama tecnológico y de investigación, y se plantean algunas de las dificultades a enfrentar. Incluye obra fotográfica de Durruty de alba, Rigo Moreno y Pablo Araiza, reproducida en blanco y negro.

  6. Las culturas no existen

    OpenAIRE

    Joel Feliu i Samuel-Lajeunesse

    2004-01-01

    Tras un somero recordatorio del hecho, a menudo olvidado, de que la cultura no es una realidad social sino tan solo un concepto, el artículo pretende argumentar en pro de la inexistencia de tal entidad (a pesar de las apariencias). La pregunta principal a la que se intenta responder es cual es el papel ideológico que tiene la idea de cultura, es decir ¿qué efectos de construcción de realidad genera? Para ello se realiza una crítica del concepto y de sus usos argumentando que tanto el concepto...

  7. en las empresas murcianas

    Directory of Open Access Journals (Sweden)

    Angel Meroño Cerdán

    2006-01-01

    Full Text Available Con el fin de aumentar la confianza de usuarios y compradores electrónicos se está desarrollando un marco regulador protagonizado por la LSSI y la LOPD. Este trabajo analiza el cumplimiento de estas leyes en materia de la información que debe presentarse en el sitio web empresarial. Sólo un 10,5% y un 14,8% de las empresas del sector servicios murcianas cumplen todos los requisitos de la LSSI y la LOPD, respectivamente. Estos resultados ponen de manifiesto el desconocimiento de estas leyes.

  8. Las pandillas transnacionales centroamericanas

    OpenAIRE

    Ortiz Vila, Ignacio

    2012-01-01

    En Centroamérica las pandillas transnacionales han tomado relevancia en el en la región en la medida que fueron expandiendo sus redes por todo el territorio. Entre sus actividades se encuentran: los secuestros, la trata de personas, el sicariato y la distribución de drogas. En la actualidad debería ser prioridad para la región encontrar una solución a través del trabajo coordinando y compartiendo experiencias que resulten efectivas para la resolución de esta problematica. Estos nuevos actores...

  9. Study of synthesis of polyethoxylated fatty alcohol sulfonate and its heat resistance, salt tolerance as well as interfacial chemical properties%醇醚磺酸盐的合成及其耐温耐盐和界面化学性能研究

    Institute of Scientific and Technical Information of China (English)

    曹翔宇; 龙海华; 崔正刚

    2011-01-01

    Polyethoxylated coconut fatty alcohol reacted with metallic sodium in benzene as reaction medium to form sodium polyethoxylated coconut fatty alcoholate, and the latter further reacted with 2 -ehloroethanesulfonate in toluene as solvent to form the product sodium polyethoxylated coconut fatty alcohol sulfonate (CAPES) with a yield of 82% achieved.Characterized by IR and MS,the final product was proved to be mixed homologues of sodium polyethoxylated C12/C14 alcohol sulfonates with n between 1 to 8.Examination to the properties of CAPES indicated that CAPES has a thermal stability of higher than 97% when dissolved in neutral or slightly alkaline aqueous media and set for 96 h at 80 ℃, which is conspicuously higher than that of sodium polyethoxylated alcohol sulfate (AES).At 45 ℃, the tolerance of CAPES to NaCl, CaC12 and MgSO4 in water reaches higher than 115,167 and 300 g/L respectively, which is equivalent to that of AES.Using CAPES as surfactant to prepare microemulsions, the optimum salinity and the salt concentration range in which middle phase microemulsions are formed are similar to that of AES.The salt tolerance of CAPES is much better than that of sodium heavy alkylbenzene sulfonates (HABS).The interfacial activity of CAPES is similar to AES but much better than sodium dodeeyl sulfate (SDS).By blending with amphoterics,CAPES can reduce Daqing crude oil/water interfacial tension to a magnitude of 10-3 mN/m at 45 ℃ without adding any alkaline agent or neutral electrolyte.%以甲苯为溶剂,用金属钠和椰油醇聚氧乙烯(3)醚反应生成醇纳,再与2-氯乙基磺酸钠反应合成了椰油醇聚氧乙烯醚磺酸钠(CAPES),产率达到82%左右.产品经红外光谱和质谱表征为C12/C14醇聚氧乙烯醚(n)磺酸盐(n=1~8).性能研究表明,CAPES在中性或微碱性水介质中于80℃下存放96 h,稳定度达到97%以上,明显高于AES;45℃下对NaCl,CaCl2,MgSO4的容忍度分别达到115,167,300g/L以上,与AES相当;CAPES微

  10. Improving the Efficacy of Conventional Therapy by Adding Andrographolide Sulfonate in the Treatment of Severe Hand, Foot, and Mouth Disease: A Randomized Controlled Trial

    OpenAIRE

    Xiuhui Li; Chi Zhang; Qingsheng Shi; Tong Yang; Qingxiong Zhu; Yimei Tian; Cheng Lu; Zhiying Zhang; Zhongsheng Jiang; Hongying Zhou; Xiaofeng Wen; Huasheng Yang; Xiaorong Ding; Lanchun Liang; Yan Liu

    2013-01-01

    Background. Herb-derived compound andrographolide sulfonate (called Xiyanping injection) recommended control measure for severe hand, foot, and mouth disease (HFMD) by the Ministry of Health (China) during the 2010 epidemic. However, there is a lack of good quality evidence directly comparing the efficacy of Andrographolide Sulfonate combination therapy with conventional therapy. Methods. 230 patients were randomly assigned to 7–10 days of Andrographolide Sulfonate 5–10 mg/Kg/day and conventi...

  11. Synthesis of Rare Metal Yttrium of Camphor Sulfonic Acid%樟脑磺酸钇的合成

    Institute of Scientific and Technical Information of China (English)

    刘晓红; 柯春兰

    2015-01-01

    This paper studied the preparation of Yttrium of L-camphor sulfonic acid and Yttrium of D-cam-phor sulfonic acid. In this experiment,racemic camphor was uesd as the raw material,and through the sulfonation reaction,split,purification and separate,chiral camphor sulfonic acid was abtained,and it can react with Y2 O3 to get yttrium of chiral Camphor sulfonic acid. The optimal synthesis conditions were:Camphor sulfonic acid concentration was 12% -15%,reaction temperature was 90 ℃,reaction time was 0. 5-1 h,Y2 O3 excessed 50%. Tested by in-frared spectroscopy( IR)and XRD,it can be found that Yttrium of Rare Metal Camphor Sulfonic Acid are consist-ent with the standard compounds.%研究了左旋樟脑磺酸钇和右旋樟脑磺酸钇的制备。实验以合成樟脑粉为原料,经过磺化反应、拆分、纯化分离等步骤得到手性樟脑磺酸,稀土金属氧化钇与手性樟脑磺酸反应合成了稀土金属樟脑磺酸钇,合成条件:樟脑磺酸质量浓度12%~15%,反应温度90℃,反应时间0.5~1 h,氧化钇过量50%。得到的产品稀土金属樟脑磺酸钇经红外光谱( IR)、XRD分析,证明与目标产物一致。

  12. CYP450-dependent biotransformation of the insecticide fipronil into fipronil sulfone can mediate fipronil-induced thyroid disruption in rats.

    Science.gov (United States)

    Roques, Béatrice B; Lacroix, Marlène Z; Puel, Sylvie; Gayrard, Véronique; Picard-Hagen, Nicole; Jouanin, Isabelle; Perdu, Elisabeth; Martin, Pascal G; Viguié, Catherine

    2012-05-01

    In rats, the widely used insecticide fipronil increases the clearance of thyroxine (T(4)). This effect is associated with a high plasma concentration of fipronil sulfone, the fipronil main metabolite in several species including rats and humans. In sheep, following fipronil treatment, fipronil sulfone plasma concentration and thyroid disruption are much lower than in rats. We postulated that fipronil biotransformation into fipronil sulfone by hepatic cytochromes P450 (CYP) could act as a potential thyroid disruptor. The aim of this study was to determine if fipronil sulfone treatment could reproduce the fipronil treatment effects on T(4) clearance and CYP induction in rats. Fipronil and fipronil sulfone treatments (3.4 μmol/kg/day per os, 14 days) increased total and free T(4) clearances to the same extent in THX + T(3), euthyroid-like rats. Both treatments induced a 2.5-fold increase in Ugt1a1 and Sult1b1 messenger RNA (mRNA) expressions and a twofold increase in UGT1A activity suggesting that T(4) elimination was mediated, at least in part, by hepatic uridine 5'-diphospho-glucuronosyltransferases (UGT) and/or sulfotransferases (SULT) induction. Both treatments induced a 10-fold increase in Cyp3a1 and Cyp2b2 mRNA expressions concomitant with a threefold increase in CYP3A immunoreactivity and a 1.7-fold increase in antipyrine clearance, a biomarker of CYP3A activity. All these results showed that fipronil sulfone treatment could reproduce the fipronil treatment effects on T(4) clearance and hepatic enzyme induction in rats. The potential of fipronil sulfone to act as a thyroid disruptor is all the more critical because it persists much longer in the organism than fipronil itself.

  13. Las carreras del futuro

    Directory of Open Access Journals (Sweden)

    Luis Piscoya Hermoza

    2011-07-01

    Full Text Available La primera década del siglo XXI ha estado signada por un énfasis en los estudiosde prospectiva, los mismos que, a partir de procesos de complejizacióny articulación de la sociedad planetaria como son la digitalización, el progresivodeterioro del medio ambiente, la necesidad del cambio de la matriz energéticay la globalización del mercado, han ensayado hipótesis para identificar lastendencias que se fortalecerán y profundizarán durante las próximas décadas.Desde el punto de vista metodológico, existen muchas maneras de clasificarlaspara conceptualizarlas y entenderlas mejor. Sin embargo, considerando lanaturaleza de esta edición nos proponemos enfocar directamente aquellas queestán estrechamente ligadas a la formación universitaria.Naturalmente, no pensamos que estamos ante tendencias inevitables en lamedida que epistemológicamente la creencia en leyes históricas deterministases insostenible y la práctica social nos muestra que la construcción del futuroes nuestra responsabilidad y siempre rebasa las mejores previsiones.

  14. Las cruces del olvido

    Directory of Open Access Journals (Sweden)

    Carla Fernandes

    2012-08-01

    Full Text Available Les tragiques événements du « mars paraguayen » ont signifié la disparition de l’espoir en la transition démocratique dans laquelle le pays s’était engagé depuis presque une dizaine d’années. Renée Ferrer, poète, dramaturge, auteur de plusieurs recueils de contes et de deux romans, consigne alors le témoignage poétique de ce drame national dans le recueil Las cruces del olvido (2001. Elle a auparavant publié d’autres textes qui peuvent rentrer dans la catégorie de la poésie sociale : c’est le cas en particulier de Viaje a destiempo (1989 dédié aux victimes de la dictature. Las cruces del olvido, dès son paratexte, insiste sur la fonction de témoignage que l’auteur souhaite assigner à ses vers et sur le rôle que ceux-ci peuvent jouer dans la transmission d’une mémoire collective. La voix d’un jeune disparu de ce « mars paraguayen », le dédoublement qu’il subit et travers lequel il évoque son entrée dans la mort et son absence du monde des vivants, rendent possible l’écriture de cette expérience de l’indicible qu’est la disparition.Los trágicos acontecimientos del «marzo paraguayo» significaron la desaparición de la esperanza en la transición democrática que el país está viviendo desde unos diez años. Renée Ferrer, poeta, dramaturga, autora de varios libros de cuentos y de dos novelas, escribe entonces el testimonio poético de ese drama nacional en su poemario Las cruces del olvido (2001. Ya había publicado antes textos que se pueden considerar como poesía social: es el caso de Viaje a destiempo (1989 dedicado a las víctimas de la dictadura. Desde el texto apertural, Las cruces del olvido potencia la función de testimonio que la autora desea conceder a sus versos y el papel que éstos pueden desempeñar en la transmisión de una memoria colectiva. La voz de un joven desaparecido del «marzo paraguayo», el desdoblamiento que sufre y a través del cual evoca su entrada en la

  15. Las promesas del imaginario Internet: las comunidades virtuales

    OpenAIRE

    Vayreda i Duran, Agnès

    2004-01-01

    Este texto se propone encontrar una respuesta a la pregunta sobre la atracción que ejerce Internet indagando en las promesas que este dispositivo nos depara. Una de las promesas que goza de mayor popularidad es la posibilidad de crear comunidades virtuales. Esta se ha ido construyendo a lo largo de más de tres décadas de diseños técnicos, experiencias y proyectos comunitarios como las primeras y restringidas comunidades de informáticos Arpanet y Usenet, las populares BBs y, más recientemente,...

  16. Las promesas del imaginario Internet: Las comunidades virtuales

    OpenAIRE

    Agnès Vayreda i Duran

    2004-01-01

    Este texto se propone encontrar una respuesta a la pregunta sobre la atracción que ejerce Internet indagando en las promesas que este dispositivo nos depara. Una de las promesas que goza de mayor popularidad es la posibilidad de crear comunidades virtuales. Esta se ha ido construyendo a lo largo de más de tres décadas de diseños técnicos, experiencias y proyectos comunitarios como las primeras y restringidas comunidades de informáticos Arpanet y Usenet, las populares BBs y, más recientemente,...

  17. Empresas excelentes entre las certificadas en las normas ISO 9000

    OpenAIRE

    Climent Serrano, Salvador

    2005-01-01

    En este trabajo se realiza un estudio entre las empresas certificadas en la norma ISO 9000 de la Comunidad Valenciana mediante una encuesta, con el objetivo de diferenciar los resultados sobre incremento de competitividad por la certificación en las normas ISO 9000, dependiendo de la involucración de las empresas en los sistemas de gestión de la calidad total, así como averiguar que factores inciden para que las empresas certificadas se impliquen en mayor medida en estos sistemas

  18. Preservar las empresas de familia

    Directory of Open Access Journals (Sweden)

    José Vargas Caicedo

    2005-12-01

    Full Text Available El ciclo de vida de las empresas de familia es usualmente corto por muchas razones. Entre las más frecuentes podemos considerar la marcada ignorancia acerca de los mecanismos adecuados para la solución de los conflictos, y este es el más común de los temas. La lucha por el poder, por la propiedad y la competencia en el cuidado de las realizaciones personales genera fricciones frecuentes entre los miembros de una familia. Las actitudes y las respuestas de tipo emocional que por lo general se dan en la solución de problemas en esta clase de organizaciones muchas veces deriva en la polarización y ruptura definitiva de las relaciones.

  19. Las habilidades comunicativas en las carreras de las Ciencias de la Salud

    Directory of Open Access Journals (Sweden)

    Juan Francisco Tejera Concepcion

    2012-06-01

    Full Text Available Fundamento: las habilidades como componentes cognitivo-instrumentales de la actuación del sujeto, han sido ampliamente estudiadas en el ámbito pedagógico para fortalecer la didáctica específica de las Ciencias de la Salud y de esta forma enseñar a los estudiantes a establecer una adecuada comunicación. Objetivo: definir las habilidades comunicativas que pueden ser tratadas mediante el sistema de conocimientos de las asignaturas y las actividades preprofesionalizantes en los estudiantes de las carreras de las Ciencias de la Salud. Métodos: del nivel teórico: histórico-lógico, inductivo-deductivo, analítico- sintético, sistémico-estructural, y la modelación; del nivel empírico: análisis de documentos, reunión con los grupos de discusión, observación, encuesta a profesores, triangulación de resultados y criterio de expertos; del nivel estadístico: análisis porcentual y método Delphi. Resultados: se definieron las habilidades comunicativas: para la expresión, habilidades para la observación y habilidades para la relación empática, para ser desarrolladas mediante el carácter sistémico e integrador de los contenidos de las asignaturas y la práctica pre-profesionalizante en las carreras de las Ciencias de la Salud. Conclusiones: las habilidades comunicativas son imprescindibles para el desempeño del futuro profesional de la Salud, es necesario que se puedan desarrollar en los estudiantes mediante la integración entre el sistema de asignaturas, los contenidos y las actividades preprofesionalizantes derivado de cada situación presentada en la práctica pedagógica y docente-asistencial.

  20. Improving the Conductivity of Sulfonated Polyimides as Proton Exchange Membranes by Doping of a Protic Ionic Liquid

    Directory of Open Access Journals (Sweden)

    Bor-Kuan Chen

    2014-10-01

    Full Text Available Proton exchange membranes (PEMs are a key component of a proton exchange membrane fuel cell. Sulfonated polyimides (SPIs were doped by protic ionic liquid (PIL to prepare composite PEMs with substantially improved conductivity. SPIs were synthesized from diamine, 2,2-bis[4-(4-amino-phenoxyphenyl]propane (BAPP, sulfonated diamine, 4,4'-diamino diphenyl ether-2,2'-disulfonic acid (ODADS and aromatic anhydride. BAPP improved the mechanical and thermal properties of SPIs, while ODADS enhanced conductivity. A PIL, 1-vinylimidazolium trifluoromethane-sulfonate ([VIm][OTf], was utilized. [VIm][OTf] offered better conductivity, which can be attributed to its vinyl chemical structure attached to an imidazolium ring that contributed to ionomer-PIL interactions. We prepared sulfonated polyimide/ionic liquid (SPI/IL composite PEMs using 50 wt% [VIm][OTf] with a conductivity of 7.17 mS/cm at 100 °C, and in an anhydrous condition, 3,3',4,4'-diphenyl sulfone tetracarboxylic dianhydride (DSDA was used in the synthesis of SPIs, leading to several hundred-times improvement in conductivity compared to pristine SPIs.

  1. Las escalas territoriales del envejecimiento

    OpenAIRE

    Puga González, Mª Dolores; Abellán García, Antonio

    2012-01-01

    El envejecimiento de la población española es uno de los cambios demográficos más importantes del siglo XX. El estudio de las diferentes escalas territoriales del proceso aporta nuevas dimensiones a su conocimiento. La escala inframunicipal es especialmente útil. La escala del hogar descubre cómo y con quién viven las personas mayores, cómo se organizan las redes y solidaridades familiares. El estudio de las formas de convivencia es un instrumento de alto valor predictivo de ne...

  2. Las cosas del quehacer

    OpenAIRE

    Sergio C. Staude

    2010-01-01

    El psicoanálisis es una praxis y no una práctica especulativa que solo busca afianzar un saber. Esta praxis encuentra su eje central en la noción de acto que es la invitación —y el sostén— a una experiencia y no a la acumulación de información. Ese acto da cuenta del tiempo de un pasaje, y el artículo destaca dos: el del momento inaugural del psicoanálisis y el de la función del psicoanalista en el devenir del análisis. A ambas las une la responsabilidad ...

  3. Las Campanas Stellar Library

    Science.gov (United States)

    Chilingarian, Igor; Zolotukhin, Ivan; Beletsky, Yuri; Worthey, Guy

    2015-08-01

    Stellar libraries are fundamental tools required to understand stellar populations in star clusters and galaxies as well as properties of individual stars. Comprehensive libraries exist in the optical domain, but the near-infrared (NIR) domain stays a couple of decades behind. Here we present the Las Campanas Stellar Library project aiming at obtaining high signal-to-noise intermediate-resolution (R=8000) NIR spectra (0.83library the largest homogeneous collection of stellar spectra covering the entire NIR domain. We also re-calibrated in flux and wavelength the two existing optical stellar libraries, INDO-US and UVES-POP and followed up about 400 non-variable stars in the NIR in order to get complete optical-NIR coverage. Worth mentioning that our current sample includes about 80 AGB stars and a few dozens of bulge/LMC/SMC stars.

  4. y las comunicaciones (TIC

    Directory of Open Access Journals (Sweden)

    Yolanda Sabín R.

    2005-01-01

    Full Text Available Uno de los problemas fundamentales a los que se enfrentan alumnos y profesores de la tarea Álvaro Reinoso (Programa MINAZ de la Universalización, es a la escasez de bibliografía básica, que en algunas ocasiones suele ser inexistente. Por esta razón un grupo de profesores de la Universidad Agraria de La Habana (UNAH, se dio a la tarea de elaborar un libro electrónico, donde se explican los conceptos fundamentales para el trabajo con el tema Cálculo diferencial en funciones de una variable, además aparecen desarrollados ejemplos para poder ser utilizados igualmente, en los cursos que se imparten en las carreras de ingenierías técnicas y agropecuarias de los diferentes centros universitarios del país

  5. Las TIC como fuente de ventaja competitiva en las PYMES

    Directory of Open Access Journals (Sweden)

    Álvaro Fernando Moncada Niño

    2013-06-01

    Full Text Available Desde su aparición, las Tecnologías de la Información y las Comunicaciones (TIC se han convertido en un recurso fundamental de las empresas para competir en la mayoría de las industrias, generalizando el planteamiento de que son fuente de ventaja competitiva. Pero realmente, ¿cuándo las TIC son fuente potencial de ventaja competitiva para las pymes? ¿Bajo qué condiciones se logra que contribuyan a generar valor y mejorar su posición competitiva? ¿Qué características deben cumplir para alcanzar y sustentar la Ventaja Competitiva? Este documento basado en la Teoría de los Recursos y Capacidades (TRC responde estas preguntas y presenta al análisis de recurso Valioso, Raro, Inimitable y Organización (VRIO como herramienta para la determinación del potencial y valor que las TIC pueden alcanzar en las pymes y cómo pueden contribuir a que la empresa alcance ventajas competitivas sostenibles, en complemento de sus recursos y capacidades organizacionales.

  6. Dejar las lagrimas e ir hacia las acciones

    DEFF Research Database (Denmark)

    Jeppesen, Anne Marie Ejdesgaard

    2015-01-01

    Este artículo enfoca en la frontera entre México y los Estados Unidos, las condiciones especiales de la sociedad fronteriza, las economías interconectadas y la violencia, en especial la violencia ejercida contra mujeres y los feminicidios. El artículo discute diferentes perspectivas y maneras de...

  7. Las TIC como fuente de ventaja competitiva en las PYMES

    Directory of Open Access Journals (Sweden)

    Álvaro Fernando Moncada Niño

    2013-07-01

    Full Text Available Desde su aparición, las Tecnologías de la Información y las Comunicaciones (TIC se han convertido en un recurso fundamental de las empresas para competir en la mayoría de las industrias, generalizando el planteamiento de que son fuente de ventaja competitiva. Pero realmente, ¿cuándo las TIC son fuente potencial de ventaja competitiva para las pymes? ¿Bajo qué condiciones se logra que contribuyan a generar valor y mejorar su posición competitiva? ¿Qué características deben cumplir para alcanzar y sustentar la Ventaja Competitiva? Este documento basado en la Teoría de los Recursos y Capacidades (TRC responde estas preguntas y presenta al análisis de recurso Valioso, Raro, Inimitable y Organización (VRIO como herramienta para la determinación del potencial y valor que las TIC pueden alcanzar en las pymes y cómo pueden contribuir a que la empresa alcance ventajas competitivas sostenibles, en complemento de sus recursos y capacidades organizacionales.

  8. Determination of petroleum sulfonates in crude oil by column-switching anion-exchange chromatography

    Institute of Scientific and Technical Information of China (English)

    Liang Zhao; Xu Long Cao; Hong Yan Wang; Xia Liu; Sheng Xiang Jiang

    2008-01-01

    A column-switching anion-exchange chromatography method was described for the separation and determination of petroleum monosulfonates (PMS)and petroleum disulfonates (PDS)in crude oil that was simply diluted with the dichloromethane/methanol (60140).The high performance liquid chromatography (HPLC)system consisted of a clean-up column and an analytical column,which were connected with two six-port switching valves.Detection of petroleum sulfonates was available and repeatable.This method has been successfully applied to determine PMS and PDS in crude oil samples from Shengli oil field.

  9. Ileocolic Perforation Secondary to Sodium Polystyrene Sulfonate in Sorbitol Use: A Case Report

    Directory of Open Access Journals (Sweden)

    Vincent Trottier

    2009-01-01

    Full Text Available Hyperkalemia is a common condition encountered in medical and surgical patients. It can lead to various complications including cardiac arrhythmias. Sodium polystyrene sulfonate (SPS in sorbitol is an ion-exchange resin that can be used to treat hyperkalemia. It can be used in enema or in oral form. The present article describes the case of an intensive care unit patient who experienced severe, diffuse, intestinal perforation induced by the use of SPS-sorbitol, requiring multiple laparotomies, followed by a brief review of the relevant literature and recommendations regarding the use of SPS-sorbitol.

  10. IONIC CONDUCTIVITY IN THE COMPLEXES OF COMB-SHAPED POLYETHER WITH LITHIUM AROMATIC SULFONATE

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shengshui; QIU Weihua; XUE Dacui; LIU Qingguo

    1993-01-01

    Complexes of comb-shaped polyether and lithium aromatic sulfonates bearing different negative charge number were prepared by in situ thermal polymerization. Their conductivity depends deeply on salt content, ambient temperature and negative charge number of the added salts. Results show that anions can be partly immobilized by increasing their negative charges at lower temperature.Against discharge time the short circuit current of the battery (Li/complex film/Lix V3O8) is stabilized by increasing the anionic charge number of the complex.

  11. The research of human exposure to polybrominated diphenyl ethers and perfluoroocatane sulfonate

    Institute of Scientific and Technical Information of China (English)

    WANG YaWei; JIANG GuiBin

    2008-01-01

    As two kinds of emerging chemicals, the pollution of polybrominated diphenyl ethers (PBDEs) and perfluoroocatane sulfonate (PFOS) has been becoming a global environmental problem. Also, research of the transport, transfer, bioaccumulation in organism, and toxicology of these two kinds of pollutant is a hotspot in environmental sciences now. In this paper, we summarize and critically review the status and progress of PBDEs and PFOS exposure to human beings. Further, data analyses based on statistical methods are done to study the characters of PBDEs and PCBs concentrations in different regions in the world.

  12. Mesoporous silica containing sulfonic acid groups as catalysts for alpha-pinene methoxylation

    OpenAIRE

    Castanheiro, J; Guerreiro, L; Fonseca, I.; Ramos, A.; Vital, J

    2008-01-01

    The methoxylation of a-pinene was studied over sulfonic acid-functionalized mesoporous silica (MCM-41, PMO) at 60ºC. The support functionalization was achieved by the introduction of 3-(mercaptopropyl)trimethoxysilane onto the surface of these materials either by grafting or by co-condensation. The thiol groups were oxidized to SO3H by treatment with H2O2. All the catalysts were active in the studied reaction being the PMO-SO3H-g the best one. Good values of selectivity to a-terpinyl methyl e...

  13. 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

    Sulfonated polyimides are among the most interesting proton exchange membrane materials with high proton conductivity and good mechanical characteristics. As a major challenge the hydrolytic instability of the polymer backbone is addressed by introducing basic moieties in the polymer main chain......(4-aminophenoxy)biphenyl-3,3'-disulfonic acid (BAPBDS) at different diamine molar ratios (BAPBDS/BIPOB, 4/1, 6/1, 9/1 and 12/1). With ion exchange capacities in the range of 1.60-2.24 meq g(-1), transparent and ductile membranes are obtained by solution casting. The incorporation of benzimiclazole...

  14. Quinolinium 8-hydroxy-7-iodoquinoline-5-sulfonate 0.8-hydrate

    OpenAIRE

    Graham Smith

    2012-01-01

    In the crystal structure of the title hydrated quinolinium salt of ferron (8-hydroxy-7-iodoquinoline-5-sulfonic acid), C9H7N+·C9H5INO4S−·0.8H2O, the quinolinium cation is fully disordered over two sites (occupancy factors fixed at 0.63 and 0.37) lying essentially within a common plane and with the ferron anions forming π–π-associated stacks down the b axis [minimum ring centroid separation = 3.462 (6) Å]. The...

  15. Polarized synchronous light scattering characterization of the interaction of proteins with sodium dodecyl sulfonate

    Institute of Scientific and Technical Information of China (English)

    ZHAO XiaoHui; HUANG ChengZhi

    2007-01-01

    In acid buffer solution, proteins with positive charge can react with anion surfactant and result in a great enhancement of synchronous light scattering (SLS) signals. In this contribution, the correlative experiment was made to compare the interaction of human serum albumin (HAS) and immunoglobulin G (IgG) with sodium dodecyl sulfonate (SDS). Based on the measurements of the polarization light scattering signals, a new method of scattering polarization was constituted to distinguish these two interaction systems with molecular weight difference (HAS 66 kDa; IgG 150 kDa). The results were consistent with the data measured by dynamic light scattering (DLS) technique.

  16. Steady-state inhibition model for the biodegradation of sulfonated amines in a packed bed reactor.

    Science.gov (United States)

    Juárez-Ramírez, Cleotilde; Galíndez-Mayer, Juvencio; Ruiz-Ordaz, Nora; Ramos-Monroy, Oswaldo; Santoyo-Tepole, Fortunata; Poggi-Varaldo, Héctor

    2015-05-25

    Aromatic amines are important industrial products having in their molecular structure one or more aromatic rings. These are used as precursors for the synthesis of dyes, adhesives, pesticides, rubber, fertilizers and surfactants. The aromatic amines are common constituents of industrial effluents, generated mostly by the degradation of azo dyes. Several of them are a threat to human health because they can by toxic, allergenic, mutagenic or carcinogenic. The most common are benzenesulfonic amines, such as 4-ABS (4-aminobenzene sulfonic acid) and naphthalene sulfonic amines, such as 4-ANS (4-amino naphthalene sulfonic acid). Sometimes, the mixtures of toxic compounds are more toxic or inhibitory than the individual compounds, even for microorganisms capable of degrading them. Therefore, the aim of this study was to evaluate the degradation of the mixture 4-ANS plus 4-ABS by a bacterial community immobilized in fragments of volcanic stone, using a packed bed continuous reactor. In this reactor, the amines loading rates were varied from 5.5 up to 69 mg L(-1) h(-1). The removal of the amines was determined by high-performance liquid chromatography and chemical oxygen demand. With this information, we have studied the substrate inhibition of the removal rate of the aromatic amines during the degradation of the mixture of sulfonated aromatic amines by the immobilized microorganisms. Experimental results were fitted to parabolic, hyperbolic and linear inhibition models. The model that best characterizes the inhibition of the specific degradation rate in the biofilm reactor was a parabolic model with values of RXM=58.15±7.95 mg (10(9) cells h)(-1), Ks=0.73±0.31 mg L(-1), Sm=89.14±5.43 mg L(-1) and the exponent m=5. From the microbial community obtained, six cultivable bacterial strains were isolated and identified by sequencing their 16S rDNA genes. The strains belong to the genera Variovorax, Pseudomonas, Bacillus, Arthrobacter, Nocardioides and Microbacterium. This

  17. LAS COCINAS DEL INFIERNO. LA VISUALIDAD DE LAS MUJERES EN LAS CALDERAS DE PEDRO BOTERO

    OpenAIRE

    Zuriaga Senent, Vicent Francesc

    2013-01-01

    Casi todas las religiones nos hablan del infierno como lugar en el que las almas son torturadas eternamente. El judaísmo lo llama Gehena, la mitología clásica Tártaro y Hades, las religiones paganas Inframundo, y la tradición cristiana castellana Las calderas de Pedro Botero. Los profetas del Antiguo Testamento narran con claridad los tormentos del infierno y Dante en La Divina Comedia nos lo relata con una visión particular. La literatura y el arte nos ofrecen abundancia de imáge...

  18. De la fraternidad de las artes: las imágenes y las palabras

    OpenAIRE

    Joly, Martine

    2004-01-01

    Se distinguen naturalmente las imágenes y las palabras como pertenecientes a universos diferentes: de un lado, aquel de las palabras, del Verbo, del pensamiento, de la creación literaria o de la información; del otro, aquel de las imágenes, del sueño, de la emoción, de la seducción o de la manipulación mediática. En la película titulada The passenger, (en francés Profession reporter), en 1974, el cineasta Michelangelo Antonioni hace decir a uno de sus personajes, traficante de armas, al di...

  19. Design, synthesis, and evaluation of 2 beta-alkenyl penam sulfone acids as inhibitors of beta-lactamases.

    Science.gov (United States)

    Richter, H G; Angehrn, P; Hubschwerlen, C; Kania, M; Page, M G; Specklin, J L; Winkler, F K

    1996-09-13

    A general method for synthesis of 2 beta-alkenyl penam sulfones has been developed. The new compounds inhibited most of the common types of beta-lactamase. The level of activity depended very strongly on the nature of the substituent in the 2 beta-alkenyl group. The inhibited species formed with the beta-lactamase from Citrobacter freundii 1205 was sufficiently stable for X-ray crystallographic studies. These, together with UV absorption spectroscopy and studies of chemical degradation, suggested a novel reaction mechanism for the new inhibitors that might account for their broad spectrum of action. The (Z)-2 beta-acrylonitrile penam sulfone Ro 48-1220 was the most active inhibitor from this class of compound. The inhibitor enhanced the action of, for example, ceftriaxone against a broad selection of organisms producing beta-lactamases. The organisms included strains of Enterobacteriaceae that produce cephalosporinases, which is an exceptional activity for penam sulfones.

  20. Synthesis of a Sulfonated Two-Dimensional Covalent Organic Framework as an Efficient Solid Acid Catalyst for Biobased Chemical Conversion.

    Science.gov (United States)

    Peng, Yongwu; Hu, Zhigang; Gao, Yongjun; Yuan, Daqiang; Kang, Zixi; Qian, Yuhong; Yan, Ning; Zhao, Dan

    2015-10-12

    Because of limited framework stability tolerance, de novo synthesis of sulfonated covalent organic frameworks (COFs) remains challenging and unexplored. Herein, a sulfonated two-dimensional crystalline COF, termed TFP-DABA, was synthesized directly from 1,3,5-triformylphloroglucinol and 2,5-diaminobenzenesulfonic acid through a previously reported Schiff base condensation reaction, followed by irreversible enol-to-keto tautomerization, which strengthened its structural stability. TFP-DABA is a highly efficient solid acid catalyst for fructose conversion with remarkable yields (97 % for 5-hydroxymethylfurfural and 65 % for 2,5-diformylfuran), good chemoselectivity, and good recyclability. The present study sheds light on the de novo synthesis of sulfonated COFs as novel solid acid catalysts for biobased chemical conversion.

  1. Synthesis of a Sulfonated Two-Dimensional Covalent Organic Framework as an Efficient Solid Acid Catalyst for Biobased Chemical Conversion.

    Science.gov (United States)

    Peng, Yongwu; Hu, Zhigang; Gao, Yongjun; Yuan, Daqiang; Kang, Zixi; Qian, Yuhong; Yan, Ning; Zhao, Dan

    2015-10-12

    Because of limited framework stability tolerance, de novo synthesis of sulfonated covalent organic frameworks (COFs) remains challenging and unexplored. Herein, a sulfonated two-dimensional crystalline COF, termed TFP-DABA, was synthesized directly from 1,3,5-triformylphloroglucinol and 2,5-diaminobenzenesulfonic acid through a previously reported Schiff base condensation reaction, followed by irreversible enol-to-keto tautomerization, which strengthened its structural stability. TFP-DABA is a highly efficient solid acid catalyst for fructose conversion with remarkable yields (97 % for 5-hydroxymethylfurfural and 65 % for 2,5-diformylfuran), good chemoselectivity, and good recyclability. The present study sheds light on the de novo synthesis of sulfonated COFs as novel solid acid catalysts for biobased chemical conversion. PMID:26448524

  2. Enhancing the phase segregation and connectivity of hydrophilic channels by blending highly sulfonated graft copolymers with fluorous homopolymers

    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...... of macro-phase segregated regions of ion-rich and PVDF-rich domains, and, at higher PVDF contents, ion-rich nano-scale domains within fluorine-rich domains. © 2013 The Royal Society of Chemistry....

  3. Influence of co-substrates in the anaerobic degradation of an anionic surfactant

    Directory of Open Access Journals (Sweden)

    D. Y. Okada

    2013-09-01

    Full Text Available The removal of linear alkylbenzene sulfonate (LAS was evaluated in a UASB reactor using short-chain alcohols (ethanol and methanol and complex co-substrate (yeast extract. Using only methanol and ethanol as co-substrates resulted in removal of LAS between 30 and 41%. At the end, addition of a complex substrate (yeast extract increased the removal of LAS to 50%. During the assay, water supply aeration increased the volatile fatty acid of the effluent (70 mg HAc.L-1 and decreased the removal of LAS (from 40 to 30%. According to the fluorescence in situ hybridization (FISH results, the amount of Archaea decreased due to water supply aeration (from 64 to 48%. Furthermore, addition of complex co-substrate increased the total anaerobic bacteria and methanogenic archaea content (three and four log units, respectively, which were estimated using the most probable number technique.

  4. Las aventuras con el autoscopio

    Directory of Open Access Journals (Sweden)

    Víctor Florencio Ramírez Hernández

    2006-01-01

    Full Text Available El trabajo se inspira en el famoso personaje Harry Potter para hacer un análisis entre la filosofía y las neurociencias, específicamente sobre las condiciones funcionales que hacen posible filosofar.

  5. Seguridad de las aplicaciones web

    OpenAIRE

    Luján Mora, Sergio

    2016-01-01

    Conferencia "Seguridad de las aplicaciones web" impartida en las III Jornadas Informáticas - UTE 2016 en la Facultad de Ciencias de la Ingeniería e Industrias de la Universidad Tecnológica Equinoccial (Quito, Ecuador) el 5 de julio de 2016.

  6. Seguridad de las aplicaciones web

    OpenAIRE

    Luján Mora, Sergio

    2014-01-01

    Conferencia "Seguridad de las aplicaciones web" impartida en las III Jornadas Informáticas - UTE 2016 en la Facultad de Ciencias de la Ingeniería e Industrias de la Universidad Tecnológica Equinoccial (Quito, Ecuador) el 5 de julio de 2016.

  7. Alkyl sulfonic acide hydrazides: Synthesis, characterization, computational studies and anticancer, antibacterial, anticarbonic anhydrase II (hCA II) activities

    Science.gov (United States)

    O. Ozdemir, Ummuhan; İlbiz, Firdevs; Balaban Gunduzalp, Ayla; Ozbek, Neslihan; Karagoz Genç, Zuhal; Hamurcu, Fatma; Tekin, Suat

    2015-11-01

    Methane sulfonic acide hydrazide, CH3SO2NHNH2 (1), ethane sulfonic acide hydrazide, CH3CH2SO2NHNH2 (2), propane sulfonic acide hydrazide, CH3CH2CH2SO2NHNH2 (3) and butane sulfonic acide hydrazide, CH3CH2CH2CH2SO2NHNH2 (4) have been synthesized as homologous series and characterized by using elemental analysis, spectrophotometric methods (1H-13C NMR, FT-IR, LC-MS). In order to gain insight into the structure of the compounds, we have performed computational studies by using 6-311G(d, p) functional in which B3LYP functional were implemented. The geometry of the sulfonic acide hydrazides were optimized at the DFT method with Gaussian 09 program package. A conformational analysis of compounds were performed by using NMR theoretical calculations with DFT/B3LYP/6-311++G(2d, 2p) level of theory by applying the (GIAO) approach. The anticancer activities of these compounds on MCF-7 human breast cancer cell line investigated by comparing IC50 values. The antibacterial activities of synthesized compounds were studied against Gram positive bacteria; Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 6633, Bacillus cereus NRRL-B-3711, Enterococcus faecalis ATCC 29212 and Gram negative bacteria; Escherichia coli ATCC 11230, Pseudomonas aeruginosa ATCC 15442, Klebsiella pneumonia ATCC 70063 by using the disc diffusion method. The inhibition activities of these compounds on carbonic anhydrase II enzyme (hCA II) have been investigated by comparing IC50 and Ki values. The biological activity screening shows that butane sulfonic acide hydrazide (4) has more activity than the others against tested breast cancer cell lines MCF-7, Gram negative/Gram positive bacteria and carbonic anhydrase II (hCA II) isoenzyme.

  8. SYNTESIS OF THE COMPLEXES OF MACROPOROUS SULFONATED RESINS WITH FERRIC CHLORIDE AND THEIR CATALYTIC BEHAVIOR FOR SETERIFICATION OF ACETIC ACID WITH BUTANOL

    Institute of Scientific and Technical Information of China (English)

    HuangWenqiang; HouXin; 等

    1997-01-01

    The complex resins prepared from macroporous sulfonated resin D72(H+ form) with ferric chloride or ferric chloride hexahydrate have both sites of Bronsted acid and Lewis acid.In the catalysis of exterification of acetic acid with butanol the complex resins show to have much higher catalytic activity than that of its matrix.a conventional sulfonated cation exchange resin D72.

  9. Functionalized immunostimulating complexes with protein A via lipid vinyl sulfones to deliver cancer drugs to trastuzumab-resistant HER2-overexpressing breast cancer cells

    Directory of Open Access Journals (Sweden)

    Rodríguez-Serrano F

    2016-09-01

    Full Text Available Fernando Rodríguez-Serrano,1,* Nuria Mut-Salud,1,* Teresa Cruz-Bustos,2 Mercedes Gomez-Samblas,2 Esther Carrasco,1 Jose Manuel Garrido,3 F Javier López-Jaramillo,4 Francisco Santoyo-Gonzalez,4 Antonio Osuna2 1Institute of Biopathology and Regenerative Medicine, 2Molecular Biochemistry and Parasitology Research Group, Department of Parasitology, Faculty of Sciences, Institute of Biotechnology, University of Granada, 3Department of Cardiovascular Surgery, Virgen de las Nieves Hospital, 4Department of Organic Chemistry, Faculty of Sciences, Institute of Biotechnology, University of Granada, Granada, Spain *These authors contributed equally to this work Background: Around 20%–30% of breast cancers overexpress the proto-oncogene human epidermal growth receptor 2 (HER2, and they are characterized by being very invasive. Therefore, many current studies are focused on testing new therapies against tumors that overexpress this receptor. In particular, there exists major interest in new strategies to fight breast cancer resistant to trastuzumab (Tmab, a humanized antibody that binds specifically to HER2 interfering with its mitogenic signaling. Our team has previously developed immunostimulating complexes (ISCOMs as nanocapsules functionalized with lipid vinyl sulfones, which can incorporate protein A and bind to G immunoglobulins that makes them very flexible nanocarriers.Methods and results: The aim of this in vitro study was to synthesize and evaluate a drug delivery system based on protein A-functionalized ISCOMs to target HER2-overexpressing cells. We describe the preparation of ISCOMs, the loading with the drugs doxorubicin and paclitaxel, the binding of ISCOMs to alkyl vinyl sulfone-protein A, the coupling of Tmab, and the evaluation in both HER2-overexpressing breast cancer cells (HCC1954 and non-overexpressing cells (MCF-7 by flow cytometry and fluorescence microscopy. Results show that the uptake is dependent on the level of overexpression

  10. ¿GENERAN VALOR LAS FUSIONES A LAS EMPRESAS COLOMBIANAS?

    Directory of Open Access Journals (Sweden)

    Gloria Martínez

    2003-01-01

    Full Text Available El presente artículo pretende demostrar si las fusiones generan o no valor a las empresas colombianas. En la primera parte se presentan cifras que muestran cómo esta estrategia empresarial ha tomado fuerza en nuestro país en los últimos años. Para comprender de manera más sencilla se presentan las herramientas utilizadas en el desarrollo del estudio, las cuales constituyen el marco teórico de la investigación; posteriormente se explica con detalle la metodología utilizada y finalmente se presentan las conclusiones obtenidas para los años 1997-1999, que son una buena aproximación para determinar cuáles son las consecuencias que este fenómeno trae para las empresas colombianas en cuanto a generación de valor, ya que el estudio pretende aislar los factores socioeconómicos que podrían limitar el alcance del estudio a un período determinado.

  11. Use of sodium polystyrene sulfonate in an acute-on-chronic lithium poisoned patient: A case report

    Directory of Open Access Journals (Sweden)

    Chakroun-Walha Olfa

    2016-03-01

    Full Text Available 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.

  12. Development and characterization of acid-doped polybenzimidazole/sulfonated polysulfone blend polymer electrolytes for fuel cells

    DEFF Research Database (Denmark)

    Hasiotis, C.; Li, Qingfeng; Deimede, V.;

    2001-01-01

    Polymeric membranes from blends of sulfonated polysulfones (SPSF) and polybenzimidazole (PBI) doped with phosphoric acid were developed as potential high-temperature polymer electrolytes for fuel cells and other electrochemical applications. The water uptake and acid doping of these polymeric...... membranes were investigated. Ionic conductivity of the membranes was measured in relation to temperature, acid doping level, sulfonation degree of SPSF, relative humidity, and blend composition. The conductivity of SPSF was of the order of 10/sup -3/ S cm/sup -1/. In the case of blends of PBI and SPSF...

  13. endo-3,3-Dimethyl-4-oxobicyclo­[3.1.0]hexan-2-yl methane­sulfonate

    Science.gov (United States)

    Kremer, Adrian; Norberg, Bernadette; Krief, Alain; Wouters, Johan

    2010-01-01

    The relative configuration of the endo isomer of the title compound, C9H14O4S, has been established and the conformation of the diastereoisomer is discussed. The five-membered ring adopts an envelope conformation. The conformation of the methane­sulfonate substituent is stabilized by inter­molecular C—H⋯O hydrogen bonds. The crystal packing results in alternating layers of polar methane­sulfonates and stacked bicyclo­hexa­nyl rings parallel to ab. PMID:21580752

  14. Hydrazine-1,2-diium bis-(3-carb-oxy-4-hy-droxy-benzene-sulfonate) tetra-hydrate.

    Science.gov (United States)

    Selvaraju, Devipriya; Venkatesh, Ranjithkumar; Sundararajan, Vairam

    2011-05-01

    Reaction of 5-sulfosalicylic acid with hydrazine hydrate at pH = 1 results in the formation of the title hydrated salt, 0.5N(2)H(6) (2+)·C(7)H(5)O(6)S(-)·2H(2)O. The hydrazinium dications lie on centres of inversion. They are located between 3-carb-oxy-4-hy-droxy-benzene-sulfonate anions, forming inter-molecular N-H⋯O hydrogen bonds with sulfonate ions and water mol-ecules of crystallisation. Further intra- and inter-molecular O-H⋯O hydrogen bonds are observed in the crystal structure. PMID:21754532

  15. Synthesis, crystal structure and properties of inorganic-organic hybrid polymers based on 8-hydroxylquinoline-5-sulfonic acid

    Institute of Scientific and Technical Information of China (English)

    WANG Ying; XUE Ming; XU JiaNing; ZHU GuangShan; QIU ShiLun

    2009-01-01

    Two new inorganic-organic hybrid polymers, Mn(QS)(H_2O) (1) and Co(QS)(H_2O)2 (2) (H2QS=8-hydroxylquinoline-5-sulfonic acid), based on 8-hydroxylquinoline-5-sulfonate ligand, have been synthesized under solvothermal conditions and their structures were solved by single-crystal X-ray diffraction analysis. Compound 1 is a three-dimensional open framework with rutile topology structure, and compound 2 is a three-dimensional supramolecular structure. These compounds were characterized by powder XRD, infrared spectroscopy, thermogravimetric analysis, fluorescence properties and magnetism properties.

  16. Synthesis,crystal structure and properties of inorganic-organic hybrid polymers based on 8-hydroxylquinoline-5-sulfonic acid

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Two new inorganic-organic hybrid polymers, Mn(QS)(H2O) (1) and Co(QS)(H2O)2 (2) (H2QS=8-hydroxyl-quinoline-5-sulfonic acid), based on 8-hydroxylquinoline-5-sulfonate ligand, have been synthesized under solvothermal conditions and their structures were solved by single-crystal X-ray diffraction analysis. Compound 1 is a three-dimensional open framework with rutile topology structure, and compound 2 is a three-dimensional supramolecular structure. These compounds were characterized by powder XRD, infrared spectroscopy, thermogravimetric analysis, fluorescence properties and magnetism properties.

  17. A study on the distribution of polystyrene sulfonic acid grafts over the cross-section of a PFA film

    International Nuclear Information System (INIS)

    In this study, the distribution behaviors of polystyrene sulfonic acid (PSSA) grafts over the cross-section of grafted PFA membranes (PFA-g-PSSA) were investigated by using SEM-EDX analysis. Membranes with various degrees of grafting (DOG) and thicknesses were prepared by a simultaneous radiation grafting of styrene and a subsequent sulfonation with chlorosulfonic acid. A SEM-EDX instrument was utilized to directly observe that the distribution behaviors of the PSSA grafts over the cross-section of grafted PFA membranes and the results showed that the distribution behaviors were largely affected by the grafting conditions such as the degree of grafting, monomer concentration, and film thickness.

  18. Pendant dual sulfonated poly(arylene ether ketone) proton exchange membranes for fuel cell application

    Science.gov (United States)

    Nguyen, Minh Dat Thinh; Yang, Sungwoo; Kim, Dukjoon

    2016-10-01

    Poly(arylene ether ketone) (PAEK) possessing carboxylic groups at the pendant position is synthesized, and the substitution degree of pendant carboxylic groups is controlled by adjusting the ratio of 4,4-bis(4-hydroxyphenyl)valeric acid and 2,2-bis(4-hydroxyphenyl)propane. Dual sulfonated 3,3-diphenylpropylamine (SDPA) is grafted onto PAEK as a proton-conducting moiety via the amidation reaction with carboxylic groups. The transparent and flexible membranes with different degrees of sulfonation are fabricated so that we can test and compare their structure and properties with a commercial Nafion® 115 membrane for PEMFC applications. All prepared PAEK-SDPA membranes exhibit good oxidative and hydrolytic stability from Fenton's and high temperature water immersion test. SAXS analysis illustrates an excellent phase separation between the hydrophobic backbone and hydrophilic pendant groups, resulting in big ionic clusters. The proton conductivity was measured at different relative humidity, and its behavior was analyzed by hydration number of the membrane. Among a series of membranes, some samples (including B20V80-SDPA) show not only higher proton conductivity, but also higher integrated cell performance than those of Nafion® 115 at 100% relative humidity, and thus we expect these to be good candidate membranes for proton exchange membrane fuel cells (PEMFCs).

  19. Modification of the cellulosic component of hemp fibers using sulfonic acid derivatives: Surface and thermal characterization.

    Science.gov (United States)

    George, Michael; Mussone, Paolo G; Bressler, David C

    2015-12-10

    The aim of this study was to characterize the surface, morphological, and thermal properties of hemp fibers treated with two commercially available, inexpensive, and water soluble sulfonic acid derivatives. Specifically, the cellulosic component of the fibers were targeted, because cellulose is not easily removed during chemical treatment. These acids have the potential to selectively transform the surfaces of natural fibers for composite applications. The proposed method proceeds in the absence of conventional organic solvents and high reaction temperatures. Surface chemical composition and signature were measured using gravimetric analysis, X-ray photoelectron spectroscopy (XPS) and Fourier transform infra-red spectroscopy (FTIR). XPS data from the treated hemp fibers were characterized by measuring the reduction in O/C ratio and an increase in abundance of the C-C-O signature. FTIR confirmed the reaction with the emergence of peaks characteristic of disubstituted benzene and amino groups. Grafting of the sulfonic derivatives resulted in lower surface polarity. Thermogravimetric analysis revealed that treated fibers were characterized by lower percent degradation between 200 and 300 °C, and a higher initial degradation temperature.

  20. Animated sulfonated or sulformethylated lignins as cement fluid loss control additives

    Energy Technology Data Exchange (ETDEWEB)

    Schilling, P.

    1991-05-07

    This patent describes a method of cementing a zone in a well penetrating a subterranean formation comprising injecting down the well and positioning in the zone to be cemented a hydraulic aqueous cement slurry composition. It comprises: a hydraulic cement, and the following expressed as parts by weight per 100 parts of the hydraulic cement, water from about 25 to 105 parts, and a fluid loss control additive comprising from about 0.5 to 2.5 parts of a compound selected from the group consisting of a sulfonated lignin and a sulfomethylated lignin, wherein the lignin has been aminated by reacting it with between about 2-5 moles of a polyamine and 2-5 moles of an aldehyde per 1,000g of the lignin, and 0.1 to 1.5 parts of a compound selected from the group consisting of sodium carbonate, sodium metasilicate, sodium phosphate, sodium sulfite and sodium naphthalene sulfonate and a combination thereof.

  1. Extraction Behavior and Wastewater Treatment of Amino Sulfonic Acid with Alamine 336

    Institute of Scientific and Technical Information of China (English)

    秦炜; 李振宇; 汪敏; 戴猷元

    2004-01-01

    p-Amino benzene sulfonic acid (PABSA) is selected as the solute with amphoteric functional group, Lewis acid and Lewis base, to be separated from its dilute solutions. An aliphatic, straight chain amine, Alamine 336, is used as the extractant, and kerosene, 1-octanol, chloroform, butyl acetate and benzene as the diluent. The effects of pH value of solution, extractant concentration, salt and types of diluent on the distribution coefficient, D, are studied. There is a peak of D value with pH value of solution, the polar diluents are favorable for extracting PABSA, and the salt in aqueous phase reduces values of D apparently. The extraction equilibrium is described using the mass action law, and the calculated data according to the proposed model agree with the experimental data well. Further, the extraction behavior for other amino benzene sulfonic acids, 1-amino-8-naphtol-3,6-disulfonic acid (H acid) and 4,4′-diaminostilbene-2,2′-disulfonic acid (DSD acid), is investigated in a wide pH value region. Finally. H acid and DSD acid are successfully removed from wastewater by the extraction with Alamine 336.

  2. Effect of a sulfonated azo dye and sulfanilic acid on nitrogen transformation processes in soil.

    Science.gov (United States)

    Topaç, F Olcay; Dindar, Efsun; Uçaroğlu, Selnur; Başkaya, Hüseyin S

    2009-10-30

    Introduction of organic dyes into soil via wastewater and sludge applications has been of increasing concern especially in developing or under-developed countries where appropriate management strategies are scarce. Assessing the response of terrestrial ecosystems to organic dyes and estimating the inhibition concentrations will probably contribute to soil remediation studies in regions affected by the same problem. Hence, an incubation study was conducted in order to investigate the impact of a sulfonated azo dye, Reactive Black 5 (RB5) and sulfanilic acid (SA), a typical representative of aromatic sulfonated amines, on soil nitrogen transformation processes. The results apparently showed that nitrogen related processes in soil can be used as bioindicators of anthropogenic stress caused by organic dyes. It was found that urease activity, arginine ammonification rate, nitrification potential and ammonium oxidising bacteria numbers decreased by 10-20% and 7-28% in the presence of RB5 (> 20 mg/kg dry soil) and SA (> 8 mg/kg dry soil), respectively. Accordingly, it was concluded that organic dye pollution may restrict the nitrogen-use-efficiency of plants, thus further reducing the productivity of terrestrial ecosystems. Furthermore, the response of soil microbiota to SA suggested that inhibition effects of the organic dye may continue after the possible reduction of the parent dye to associated aromatic amines.

  3. The limits of proton conductivity in polymeric sulfonated membranes: A modelling study

    Energy Technology Data Exchange (ETDEWEB)

    Pisani, L. [CRS4, Parco Scientifico e Tecnologico, Polaris - Edificio 1, 09010 Pula, CA (Italy)

    2009-10-20

    In this work, the conductivity limits of sulfonated membranes are investigated through a model analysis. A recent analytical conductivity model has been modified by reducing the number of variables to only three parameters, representing the hydration level, the ion exchange capacity and the morphology of the membrane. The effects of these parameters on the conductivity are investigated through a parametric analysis, showing significant trends. Particular values of the morphology parameter define ideal conditions, in which the model conductivities constitute upper limits for real membranes. In particular, the model conditions of ''ideal isotropic membrane'' and ''ideal non-tortuous membrane'' are compared with the experimental proton conductivity of a number of polymeric membranes in the literature. It appears that membranes such as Nafion and Dow are close to the condition of ''ideal isotropic membrane'', and their conductivity can be improved only by decreasing their tortuosity. On the other hand, the conductivity of other sulfonated polymers as SPEEK is well below the limit and can be enhanced by improving the membrane percolation properties. (author)

  4. A highly aromatic and sulfonated ionomer for high elastic modulus ionic polymer membrane micro-actuators

    International Nuclear Information System (INIS)

    A high modulus, sulfonated ionomer synthesized from 4,6-bis(4-hydroxyphenyl)-N,N-diphenyl-1,3,5-triazin-2-amine and 4,4′-biphenol with bis(4-fluorophenyl)sulfone (DPA-PS:BP) is investigated for ionic polymer actuators. The uniqueness of DPA-PS:BP is that it can have a high ionic liquid (IL) uptake and consequently generates a high intrinsic strain response, which is >1.1% under 1.6 V while maintaining a high elastic modulus (i.e. 600 MPa for 65 vol% IL uptake). Moreover, such a high modulus of the active ionomer, originating from the highly aromatic backbone and side-chain-free structure, allows for the fabrication of free-standing thin film micro-actuators (down to 5 µm thickness) via the solution cast method and focused-ion-beam milling, which exhibits a much higher bending actuation, i.e. 43 µm tip displacement and 180 kPa blocking stress for a 200 µm long and 5 µm thick cantilever actuator, compared with the ionic actuators based on traditional ionomers such as Nafion, which has a much lower elastic modulus (50 MPa) and actuation strain. (paper)

  5. Synthesis, characterization, antibacterial activity and quantum chemical studies of N'-Acetyl propane sulfonic acid hydrazide

    Science.gov (United States)

    Alyar, Saliha; Alyar, Hamit; Ozdemir, Ummuhan Ozmen; Sahin, Omer; Kaya, Kerem; Ozbek, Neslihan; Gunduzalp, Ayla Balaban

    2015-08-01

    A new N'-Acetyl propane sulfonic acid hydrazide, C3H7sbnd SO2sbnd NHsbnd NHsbnd COCH3 (Apsh, an sulfon amide compound) has been synthesized for the first time. The structure of Apsh was investigated using elemental analysis, spectral (IR, 1H/13C NMR) measurements. In addition, molecular structure of the Apsh was determined by single crystal X-ray diffraction technique and found that the compound crystallizes in monoclinic, space group P 21/c. 1H and 13C shielding tensors for crystal structure were calculated with GIAO/DFT/B3LYP/6-311++G(d,p) methods in CDCl3. The structure of Apsh is optimized using Density Functional Theory (DFT) method. The vibrational band assignments were performed at B3LYP/6-311++G(d,p) theory level combined with scaled quantum mechanics force field (SQMFF) methodology. The theoretical IR frequencies are found to be in good agreement with the experimental IR frequencies. Nonlinear optical (NLO) behaviour of Apsh is also examined by the theoretically predicted values of dipole moment (μ), polarizability (α0) and first hyperpolarizability (βtot). The antibacterial activities of synthesized compound were studied against Gram positive bacteria: Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 23212, Staphylococcus epidermidis ATCC 34384, Gram negative bacteria: Eschericha coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 70063 by using microdilution method (as MICs) and disc diffusion method.

  6. Fabrication of protic ionic liquid/sulfonated polyimide composite membranes for non-humidified fuel cells

    Science.gov (United States)

    Lee, Seung-Yul; Yasuda, Tomohiro; Watanabe, Masayoshi

    We have demonstrated that a protic ionic liquid, diethylmethylammonium trifluoromethanesulfonate ([dema][TfO]) functions as a proton conductor and is suitable for use as an electrolyte in H 2/O 2 fuel cells, which can be operated at temperatures higher than 100 °C under non-humidified conditions. In this study, in order to fabricate a polymer electrolyte fuel cell, matrix polymers for [dema][TfO] are explored and sulfonated polyimides (SPI), in which the sulfonic acid groups are in diethylmethylammonium form, are found to be highly compatible with [dema][TfO]. Polymer electrolyte membranes for non-humidified fuel cells are prepared by the solvent casting method using SPI and [dema][TfO]. The SPI, with an ion exchange capacity of 2.27 meq g -1, can retain four times its own weight of [dema][TfO] and produces uniform, tough, and transparent composite membranes. The composite membranes have good thermal stability (>300 °C) and ionic conductivity (>10 -2 S cm -1 at 120 °C when the [dema][TfO] content is higher than 67 wt%) under anhydrous conditions. In the H 2/O 2 fuel cell operation using a composite membrane without humidification, a current density higher than 240 mA cm -2 is achieved with a maximum power density of 100 mW cm -2 at 80 °C.

  7. Gargling with sodium azulene sulfonate reduces the postoperative sore throat after intubation of the trachea.

    Science.gov (United States)

    Ogata, Junchi; Minami, Kouichiro; Horishita, Takafumi; Shiraishi, Munehiro; Okamoto, Takashi; Terada, Tadanori; Sata, Takeyoshi

    2005-07-01

    Postoperative sore throat (POST) is a complication that remains to be resolved in patients undergoing endotracheal intubation. In this study, we investigated whether preoperative gargling with sodium 1,4-dimethyl-7-isopropylazulene-3-sulfonate monohydrate (sodium azulene sulfonate, Azunol) reduces POST after endotracheal intubation. Forty patients scheduled for elective surgery under general anesthesia were randomized into Azunol and control groups. In the Azunol group, patients gargled with 4 mg Azunol diluted with 100 mL tap water (40 microg/mL). In the control group, patients gargled with 100 mL of tap water. After emergence from general anesthesia, the patients with POST were counted and POST was evaluated using a verbal analog pain scale. There were no significant differences between the two groups by age, height, body weight, gender distribution, or duration of anesthesia and surgery. In the control group, 13 patients (65%) complained of POST, which remained 24 h later in nine patients (45%). In the Azunol group, five patients (25%) also complained of POST, which completely disappeared by 24 h later. The incidence of POST and verbal analog pain scale scores in the Azunol group decreased significantly compared with the control group. We demonstrated that gargling with Azunol effectively attenuated POST with no adverse reactions.

  8. Design, synthesis and physical properties of poly(styrene–butadiene–styrene)/poly(thiourea-azo-sulfone) blends

    Indian Academy of Sciences (India)

    Ayesha Kausar

    2014-06-01

    A new aromatic azo-polymer, poly(thiourea-azo-sulfone), has been synthesized using 1-(4-thiocarbamoylaminophenylsulfonylphenyl)thiourea and diazonium salt solution. Conducting and thermally stable rubbery blends of poly(styrene-block-butadiene-block-styrene) (SBS) triblock copolymer and poly(thiourea-azo-sulfone) (PTAS) were produced by solution blending technique. PTAS possessed fine solubility in polar solvents and high molar mass 63 × 103 g moL-1. Microscopic analysis on SBS/PTAS blends revealed good adhesion between the two polymers without macro phase separation. Electrical conductivity measurement recommended that blending of SBS with 60% PTAS was sufficiently conducting 1.43 S cm-1. A relationship between PTAS loading and thermal stability of blends was observed. With the increasing PTAS content, 10% gravimetric loss was increased from 481 to 497 °C, while glass transition improved from 123 to 136 °C (better than neat SBS but lower than PTAS). The blends also established higher tensile strength (52.40–59.96 MPa) relative to SBS. Fine balance of properties renders new SBS/PTAS, potential engineering plastics for a number of aerospace relevance.

  9. SYNTHESIS AND CHARACTERIZATION OF PHTHALAZINONE POLY(ARYL ETHER SULFONE KETONE) WITH CARBONYL GROUP

    Institute of Scientific and Technical Information of China (English)

    Ying-nan Xuan; Ya Gao; Yong Huang; Xi-gao Jian

    2002-01-01

    A kind of novel heat-resistant, high performance engineering thermoplastic phthalazinone poly(aryl ether sulfone ketone) (PPESK) containing a carboxyl group in its side chain was prepared by the nucleophilic displacement reaction of 4-(4-hydroxylphenyl)-1(2H)-phthalazinone with di(4-chlorophenyl) sulfone, 4,4'-difluoro-benzophenone and phenolphthalin in sulfolane in the presence of K2CO3 to produce high molecular weight polymers which can be dissolved in some polar solvents such as chloroform and nitrobenzene at room temperature and can be easily cast into flexible, yellowish and transparent films. PPESK is an amorphous polymer having a decomposition temperature above 400℃, which indicates that it has high thermal stability. At the same time, the thermal properties of PPESKs with dicyandiamide (DICY) as curing agent indicated that the heat-resistance properties of the PPESKs are improved after curing. The apparent activation energy (△E) of the cross-linking reaction and the reaction order (n) of PPESK/DICY were found to be 52.2 kJ/mol and ca. 1.0, respectively.Therefore, the cross-linking reaction is approximately a first order reaction.

  10. Sulfonation of polyester fabrics by gaseous sulfur oxide activated by UV irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kordoghli, Bessem [Laboratory of Applied Chemical and Environment (UR-CAE) - University of Monastir (Tunisia); Textile Research Laboratory (LRT) - ISET Kasr Hellal, University of Monastir (Tunisia); Khiari, Ramzi, E-mail: khiari_ramzi2000@yahoo.fr [Laboratory of Applied Chemical and Environment (UR-CAE) - University of Monastir (Tunisia); LGP2 - Laboratory of Pulp and Paper Science, 461, Rue de la Papeterie - BP 65, 38402 Saint Martin d' Heres Cedex (France); Mhenni, Mohamed Farouk [Laboratory of Applied Chemical and Environment (UR-CAE) - University of Monastir (Tunisia); Sakli, Faouzi [Textile Research Laboratory (LRT) - ISET Kasr Hellal, University of Monastir (Tunisia); Belgacem, Mohamed Naceur [LGP2 - Laboratory of Pulp and Paper Science, 461, Rue de la Papeterie - BP 65, 38402 Saint Martin d' Heres Cedex (France)

    2012-10-01

    Highlights: Black-Right-Pointing-Pointer In this paper, an original technique was present to improve the hydrophilic properties of polyester fibres. Black-Right-Pointing-Pointer The modification of PET fabric was carried out using gaseous sulfur trioxide activated by UV irradiations. Black-Right-Pointing-Pointer We fully characterized the modified and untreated fabrics. - Abstract: This paper describes an original technique aiming to improve the hydrophilic properties of polyester fibres. In this method, the sulfonation of the aromatic rings is carried out using gaseous sulfur trioxide activated by UV irradiations. Thus, exposing the polyester textile fabric to the UVC light (wavelength around 254 nm) under a stream of sulfur trioxide leads to the fixation of -SO{sub 3}H groups. The amounts of the fixed sulfonate groups depended on the reaction conditions. Evidence of grafting deduced from the measurements of hygroscopic properties was carried out by contact angle measurement, moisture regain as well as by measuring the rate of retention. SEM and FT-IR analysis, DSC and DTA/TGA thermograms showed that no significant modifications have occurred in the bulk of the treated PET fabrics.

  11. Bioseparation of papain from Carica papaya latex by precipitation of papain-poly (vinyl sulfonate) complexes.

    Science.gov (United States)

    Braia, Mauricio; Ferrero, Maximiliano; Rocha, María Victoria; Loureiro, Dana; Tubio, Gisela; Romanini, Diana

    2013-09-01

    The formation of insoluble complexes between enzymes and polyelectrolytes is a suitable technique for isolating these biomolecules from natural sources, because it is a simple and rapid technique that allows the concentration of the protein. This technique can be used in most purification protocols at the beginning of the downstream process. The aim of this investigation is to isolate papain from Carica papaya latex by precipitation of insoluble complexes between this enzyme and poly (vinyl sulfonate). The papain-poly (vinyl sulfonate) complex was insoluble at pH lower than 6, with a PVS/PAP stoichiometric ratio of 1:279. Ionic strength affected the complex formation. The presence of the polymer increased the enzymatic activity and protected the enzyme from autodegradation. The optimal conditions for the formation of insoluble papain-polyelectrolyte complex formation were applied to C. papaya latex and a high recovery was obtained (around 86%) and a purification factor around 2. This method can be applied as an isolation method of papain from C. papaya latex or as a first step in a larger purification strategy.

  12. Interfacial assignment of branched-alkyl benzene sulfonates: A molecular simulation

    Directory of Open Access Journals (Sweden)

    Zi-Yu Liu

    2015-11-01

    Full Text Available A molecular dynamics simulation was conducted to analyze orientations of sodium branched-alkyl benzene sulfonates molecules at nonane/water interface, which is helpful to design optimal surfactant structures to achieve ultralow interfacial tension (IFT. Through the two dimensional density profiles, monolayer collapses are found when surfactant concentration continues to increase. Thus the precise scope of monolayer is certain and orientation can be analyzed. Based on the simulated results, we verdict the interfacial assignment of branched-alkyl benzene sulfonates at the oil-water interface, and discuss the effect of hydrophobic tail structure on surfactant assignment. Bigger hydrophobic size can slow the change rate of surfactant occupied area as steric hindrance, and surfactant meta hydrophobic tails have a stronger tendency to stretch to the oil phase below the collapsed concentration. Furthermore, an interfacial model with reference to collapse, increasing steric hindrance and charge repulsive force between interfacial surfactant molecules, responsible for effecting of surfactant concentration and structure has been supposed.

  13. Physicochemical pretreatments and hydrolysis of furfural residues via carbon-based sulfonated solid acid.

    Science.gov (United States)

    Ma, Bao Jun; Sun, Yuan; Lin, Ke Ying; Li, Bing; Liu, Wan Yi

    2014-03-01

    Potential commercial physicochemical pretreatment methods, NaOH/microwave and NaOH/ultrasound were developed, and the carbon-based sulfonated solid acid catalysts were prepared for furfural residues conversion into reducing sugars. After the two optimum pretreatments, both the content of cellulose increased (74.03%, 72.28%, respectively) and the content of hemicellulose (94.11%, 94.17% of removal rate, respectively) and lignin (91.75%, 92.09% of removal rate, respectively) decreased in furfural residues. The reducing sugar yields of furfural residues with the two physicochemical pretreatments on coal tar-based solid acid reached 33.94% and 33.13%, respectively, higher than that pretreated via NaOH alone (27%) and comparable to that pretreated via NaOH/H2O2 (35.67%). The XRD patterns, IR spectra and SEM images show microwave and ultrasound improve the pretreatment effect. The results demonstrate the carbon-based sulfonated solid acids and the physicochemical pretreatments are green, effective, low-cost for furfural residues conversion.

  14. Synthetic approach of norbadione A: new preparation of alcohols from sulfones and boron compounds

    International Nuclear Information System (INIS)

    The synthetic approach of norbadione A, a pigment from mushrooms related to pulvinic acids, was studied. This compound has the property to complex caesium and has shown an antioxidant activity. The first strategy, based on a double Suzuki-Miyaura coupling between a naphtho-lactone with two boron functions and two pulvinic moieties with a triflate was unsuccessful and has shown a deactivating effect of the lactone. Modifications aimed to inhibit the electro-attracting character of the lactone permitted to obtain a bis(coupled) product with a poor yield. A second approach based on a the cyclization of enol aryl-acetates was studied in order to build the pulvinic moiety in several steps. The important reaction of introduction of an alkyl-acetate from a triflate was realised by a palladium-mediated coupling. The cyclization attempts carried out using a naphthalenic compound allowed us to isolate a monocyclised product. A parallel study was to first build a tetronic moiety and then to construct the exocyclic double bond by a method developed in the laboratory for the preparation of an iodated pulvinic compound. Finally, a new preparation of alcohols from sulfones and boron compounds was developed. Two known reactions in the chemistry of boron were combined. The first one is the reaction between anions of sulfones and tri-alkyl-boranes, the second one is a thermal isomerization which places the boron atom in a terminal position. A new preparation of primary alcohols was thus carried out. (author)

  15. Sulfonation of polyester fabrics by gaseous sulfur oxide activated by UV irradiation

    International Nuclear Information System (INIS)

    Highlights: ► In this paper, an original technique was present to improve the hydrophilic properties of polyester fibres. ► The modification of PET fabric was carried out using gaseous sulfur trioxide activated by UV irradiations. ► We fully characterized the modified and untreated fabrics. - Abstract: This paper describes an original technique aiming to improve the hydrophilic properties of polyester fibres. In this method, the sulfonation of the aromatic rings is carried out using gaseous sulfur trioxide activated by UV irradiations. Thus, exposing the polyester textile fabric to the UVC light (wavelength around 254 nm) under a stream of sulfur trioxide leads to the fixation of -SO3H groups. The amounts of the fixed sulfonate groups depended on the reaction conditions. Evidence of grafting deduced from the measurements of hygroscopic properties was carried out by contact angle measurement, moisture regain as well as by measuring the rate of retention. SEM and FT-IR analysis, DSC and DTA/TGA thermograms showed that no significant modifications have occurred in the bulk of the treated PET fabrics.

  16. Clean synthesis of biodiesel over solid acid catalysts of sulfonated mesopolymers

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    FDU-15-SO3H,a solid acid material prepared from the sulfonation of FDU-15 mesoporous polymer,has been demonstrated to serve as an efficient catalyst in the esterification of palmitic acid with methanol as well as in the transesterification of fatty acid-edible oil mixture.FDU-15-SO3H achieved an acid conversion of 99.0% when the esterification was carried out at 343 K with a methanol/palmitic acid molar ratio of 6:1 and 5 wt% catalyst loading.It was capable of giving 99.0% yield of fatty acid methyl esters (FAME) when the transesterification of soybean oil was performed at 413 K and the methanol/oil weight ratio of 1:1.FDU-15-SO3H was further applied to the transesterification/esterification of the oil mixtures with a varying ratio of soybean oil to palmitic acid,which simulated the feedstock with a high content of free fatty acids.The yield of FAME reached 95% for the oil mixtures containing 30 wt% palmitic acid.This indicated the sulfonated mesopolymer was a potential catalyst for clean synthesis of fuel alternative of biodiesel from the waste oil without further purification.

  17. Las redes sociales entre las TICS y la decadencia moral

    OpenAIRE

    Domingo Alarcón Ortiz; Antonio Francisco Díaz García

    2013-01-01

    La paradoja de las redes sociales en las organizaciones es que constituyen un medio muy importante de formación, capacitación, actualización, información y comunicación, pero también representan un síntoma de decadencia cultural, porque con ellas se han facilitado los procesos de desinformación incontrolados y de distribución de información maliciosa, con la cual se agrede a las personas. El abuso en cuanto a subir información de manera indiscriminada lleva a presentar comportamientos cínicos...

  18. Membranes of polyindene sulfonated and PVA for use as polymer electrolyte; Membranas mistas de poli(indeno) sulfonado e PVA para uso como eletrolito polimerico

    Energy Technology Data Exchange (ETDEWEB)

    Loser, N.; Silva, B.B.R. da; Brum, F.J.B.; Forte, M.M.C. [Universidade Federal do Rio Grande do Sul - Escola de Engenharia, Porto Alegre, RS (Brazil)

    2010-07-01

    This study is focused on developing polymer poly electrolytes for fuel cell PEM and aims to evaluate the efficiency of sulfonated polyindene as A polymer electrolyte in blends with poly (vinyl alcohol) (PVA). For this, polyindene synthesized in the lab was functionalized with sulfonic groups (-SO{sub 3}H), using as sulfonation agent acetyl sulfate in 1,2-dichloroethane. The membranes of sulfonated polyindene (SPInd) and PVA were prepared in aqueous medium, using glutaraldehyde as a PVA cross linker. The membranes SPInd/PVA were evaluated on the content of sulfonic groups, ion exchange capacity (IEC), degree of swelling in water and thermal stability (TGA). Electrochemical impedance analysis was used for ionic conductivity evaluation and DMA for the mechanical strength of the membranes. Preliminary results show that the membranes showed ion exchange capacity about 3.2 m equiv/g and degree of swelling in water of 550%. (author)

  19. Synthesis, Characterization, and Catalytic Activity of Sulfonated Carbon-Based Catalysts Derived From Rubber Tree Leaves and Pulp and Paper Mill Waste

    Science.gov (United States)

    Janaun, J.; Sinin, E.; Hiew, S. F.; Kong, A. M. T.; Lahin, F. A.

    2016-06-01

    Sulfonated carbon-based catalysts derived from rubber tree leaves, and pulp and paper mill waste were synthesized and characterized. Three types of catalyst synthesized were sulfonated rubber tree leaves (S-RTL), pyrolysed sludge char (P-SC) and sulfonated sludge char (S-SC). Sulfonated rubber tree leaves (S-RTL) and sulfonated sludge char (S-SC) were prepared through pyrolysis followed by functionalization via sulfonation process whereas, P- SC was only pyrolyzed without sulfonation. The characterization results indicated sulfonic acids, hydroxyl, and carboxyl moieties were detected in S-RTL and S-SC, but no sulfonic acid was detected in P-SC. Total acidity test showed S-RTL had the highest value followed by S-SC and P-SC. The thermal stability of S-RTL and S-SC were up to 230oC as the loss was associated with the decomposition of sulfonic acid group, whereas, P-SC showed higher stability than the S-RTL and S-SC. Morphology analysis showed that S-RTL consisted of an amorphous carbon structure, and a crystalline structure for P-SC and S-SC. Furthermore, traces of metal components were also detected on all of the catalysts. The catalyst catalytic activity was tested through esterification of oleic acid with methanol. The results showed that the reaction using S-RTL catalyst produced the highest conversion (99.9%) followed by P-SC (88.4%) and lastly S-SC (82.7%). The synthesized catalysts showed high potential to be used in biodiesel production.

  20. Las aristas del racismo

    Directory of Open Access Journals (Sweden)

    Fredy Rivera Vélez

    2000-01-01

    Full Text Available En el presente trabajo se estudia un ámbito que normalmente se esquiva y se enmascara: Las prácticas racistas. Esta evasión del tema se da en diferentes planos discursivos, y es una práctica, cada vez más frecuente en América Latina, pues aquí se hace de la integración étnica uno de los ejes centrales de la construcción de sus relaciones identitarias y políticas. Se propone, entonces, este trabajo develar la naturaleza y el movimiento de prácticas racistas presentes no sólo discursivamente, en la práctica política, en la práctica laboral, sino que también están presente en nuestra vida cotidiana, bajo nuevas formas y contenidos que se distancian del racismo tradicional e incorpora una nueva gramática racista, una suerte de racismo moderno, no basado en el fenotipo o características físicas como elemento central, sino en un racismo basado en la diferencia cultural, lo cual plantea un plano más excluyente, pues en este planteamiento el “objeto de racismo” no es un objeto de racismo limitado, como en el racismo tradicional, en el cual siempre es utilizado por quien practica el racismo; en el racismo contemporáneo se pretende una ruptura completa y una exclusión total del otro.

  1. Las multitudes y las revoluciones de nuestro tiempo

    Directory of Open Access Journals (Sweden)

    John Harold Biervliet

    2015-08-01

    Full Text Available Este artículo examina el motivo de las multitudes y las revoluciones de nuestro tiempo. Primeramente, se discuten las diferencias entre los conceptos de multitud y masa. Así, podemos considerar las revoluciones como acontecimientos de cambios sociales, económicos y políticos, provenientes de las clases baja y media de la sociedad. El meollo de este artículo refiere a la dignidad humana articulada a la contracción de los Estados de bienestar. Los ciudadanos están reflejando un desencanto hacia la clase política y una frustración con respecto al empeoramiento de las condiciones económicas y sociales. Podemos observar los casos de indignados en Grecia, España y Portugal pero también en los países árabes. De esta misma manera, las revoluciones de las multitudes siguen avanzando por medio de las demostraciones públicas y protestas sobre los espacios geográficos. Finalmente, las dinámicas de cambio a través de las revoluciones árabes son una cuestión compleja debido al círculo vicioso entre la tendencia autoritaria y la islámica. This article examines the reason of multitudes and revolutions in our time. First of all, it discusses the difference between the concept of multitude and mass. Consequently, revolutions can be considered as social, economic, and political events of changes, which come from the low and middle classes of the society. This article refers to the human dignity articulated with the contraction of Welfare states. Citizens are reflecting disenchantment towards the political class and frustration regarding the deterioration of social and economic conditions. We can observe angry people in Greece, Spain, and Portugal but also in Arabian countries. In this same way, revolutions of multitudes continue by means of public demonstrations and protests on geographical spaces. Finally, the dynamics of change through Arabian Revolutions are a complex matter due to the vicious circle between the authoritarian or Islamic

  2. Unificar las ciencias del deporte

    Directory of Open Access Journals (Sweden)

    Natàlia Balagué Serre

    2013-12-01

    Full Text Available El deporte no es solo un fenómeno social de nuestro mundo, sino que también es un campo privilegiado para el estudio del comportamiento social y humano. Durante las últimas décadas, se ha producido un enorme crecimiento y especialización de las ciencias del deporte y el lema del 18º Congreso del European College of Sport Sciences (ECSS “Unificar las ciencias del deporte” representa desafiar este proceso de fragmentación. El lema conlleva un cambio de la especialización a la integración, de una concepción de los sistemas vivos basada en la teoría de la información y la ingeniería a una de base biológica, de la investigación multidisciplinaria a la transdisciplinaria. Pero aparece una pregunta: ¿es posible integrar las áreas fragmentadas y facilitar la transferencia de los principios explicativos teóricos, técnicas y perspectivas metodológicas entre disciplinas? En el marco de las contribuciones hechas en el congreso, este artículo tiene como objetivo introducir enfoques científicos ya extendidos en los ámbitos de la física, la química, la biología (incluyendo las ómicas y las ciencias sociales, y que centradas en las interacciones dinámicas complejas de los componentes sistémicos (proteínas, células, organismos, grupos, sociedades, revelan principios explicativos generales que contribuyen a la unificación del conocimiento. Intentamos animar a las personas interesadas en las ciencias del deporte a percibir nuevas formas de investigación y a complementar, sin sustituirlos, los enfoques dominantes, con la esperanza de que ir de las partes al todo y del todo a las partes ayudará a los científicos a reconocer los caminos más adecuados.

  3. Aplicaciones de las Peliculas Delgadas en Microelectronica

    OpenAIRE

    Zimmerman, Rosa; Broitman, Esteban

    1986-01-01

    En este articulo se presenta una reseña acerca del uso de las peliculas delgadas en microelectronica con especial enfasis en las peliculas resistivas. Se detallan las propiedades electricas de la aleacion niquel-cromo.

  4. PARTIAL LIFE-CYCLE TOXICITY AND BIOCONCENTRATION MODELLING OF PERFLUOROOCTANE SULFONATE (PFOS) IN THE NORTHERN LEOPARD FROG (RANA PIPIENS)

    Science.gov (United States)

    A number of recent monitoring studies have demonstrated elevated concentrations of perfluorooctane sulfonate (PFOS) in humans and wildlife throughout the world. Although no longer manufactured in the U.S., the global distribution and relative persistence of PFOS indicates a need ...

  5. Partially Fluorinated Sulfonated Poly(ether amide Fuel Cell Membranes: Influence of Chemical Structure on Membrane Properties

    Directory of Open Access Journals (Sweden)

    Chulsung Bae

    2011-01-01

    Full Text Available A series of fluorinated sulfonated poly (ether amides (SPAs were synthesized for proton exchange membrane fuel cell applications. A polycondensation reaction of 4,4’-oxydianiline, 2-sulfoterephthalic acid monosodium salt, and tetrafluorophenylene dicarboxylic acids (terephthalic and isophthalic or fluoroaliphatic dicarboxylic acids produced SPAs with sulfonation degrees of 80–90%. Controlling the feed ratio of the sulfonated and unsulfonated dicarboxylic acid monomers afforded random SPAs with ion exchange capacities between 1.7 and 2.2 meq/g and good solubility in polar aprotic solvents. Their structures were characterized using NMR and FT IR spectroscopies. Tough, flexible, and transparent films were obtained with dimethylsulfoxide using a solution casting method. Most SPA membranes with 90% sulfonation degree showed high proton conductivity (>100 mS/cm at 80 °C and 100% relative humidity. Among them, two outstanding ionomers (ODA-STA-TPA-90 and ODA-STA-IPA-90 showed proton conductivity comparable to that of Nafion 117 between 40 and 80 °C. The influence of chemical structure on the membrane properties was systematically investigated by comparing the fluorinated polymers to their hydrogenated counterparts. The results suggest that the incorporation of fluorinated moieties in the polymer backbone of the membrane reduces water absorption. High molecular weight and the resulting physical entanglement of the polymers chains played a more important role in improving stability in water, however.

  6. The effects of water on the morphology and the swelling behavior of sulfonated poly(ether ether ketone) films

    NARCIS (Netherlands)

    Koziara, B.T.; Akkilic, N.; Nijmeijer, K.; Benes, N.E.

    2016-01-01

    Thin sulfonated poly(ether ether ketone) films swell excessively in water. The extent of water-induced swelling is shown to be correlated with the optical anisotropy of the films, due to two distinct phenomena. Firstly, the optical anisotropy is directly related to the amount of water taken up from

  7. The Electrochemical Characteristics of Multilayer Assembly of Hemoglobin and Polystyrene Sulfonate at Self-assembled Monolayer Surface

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A multilayer film of hemoglobin (Hb) molecules and polyelectrolyte sulfonate were fabricated on a thiol self-assembled monolayers (SAMs) by electrostatic force.The Hb maintains electroactive property in the multilayer film, methylene blue (MB) incorporated into the multilayer can enhance the electron transfer rate between the Hb and the electrode surface.

  8. Silica Bonded S-Sulfonic Acid: A Recyclable Catalyst for the Synthesis of Quinoxalines at Room Temperature

    Directory of Open Access Journals (Sweden)

    Khodabakhsh Niknam

    2009-05-01

    Full Text Available The reaction of 3-mercaptopropylsilica (MPS and chlorosulfonic acid in chloroform afforded silica bonded S-sulfonic acid (SBSSA, which was used as a catalyst for the room temperature synthesis of quinoxaline derivatives from 1,2-diamino compounds and 1,2-dicarbonyl compounds. The catalyst could be recycled and reused several times without any loss of efficiency.

  9. Analysis of recycled poly (styrene-co-butadiene) sulfonation: a new approach in solid catalysts for biodiesel production.

    Science.gov (United States)

    Aguilar-Garnica, Efrén; Paredes-Casillas, Mario; Herrera-Larrasilla, Tito E; Rodríguez-Palomera, Felicia; Ramírez-Arreola, Daniel E

    2013-01-01

    The disposal of solid waste is a serious problem worldwide that is made worse in developing countries due to inadequate planning and unsustainable solid waste management. In Mexico, only 2% of total urban solid waste is recycled. One non-recyclable material is poly (styrene-co-butadiene), which is commonly used in consumer products (like components of appliances and toys), in the automotive industry (in instrument panels) and in food services (e.g. hot and cold drinking cups and glasses). In this paper, a lab-scale strategy is proposed for recycling poly (styrene-co-butadiene) waste by sulfonation with fuming sulfuric acid. Tests of the sulfonation strategy were carried out at various reaction conditions. The results show that 75°C and 2.5 h are the operating conditions that maximize the sulfonation level expressed as number of acid sites. The modified resin is tested as a heterogeneous catalyst in the first step (known as esterification) of biodiesel production from a mixture containing tallow fat and canola oil with 59% of free fatty acids. The preliminary results show that esterification can reach 91% conversion in the presence of the sulfonated polymeric catalyst compared with 67% conversion when the reaction is performed without catalyst. PMID:24098857

  10. Preparation of sulfonic-functionalized graphene oxide as ion-exchange material and its application into electrochemiluminescence analysis.

    Science.gov (United States)

    Chen, Guifen; Zhai, Shengyong; Zhai, Yanling; Zhang, Ke; Yue, Qiaoli; Wang, Lei; Zhao, Jinsheng; Wang, Huaisheng; Liu, Jifeng; Jia, Jianbo

    2011-03-15

    Graphene oxide (GO) obtained from chemical oxidation of flake graphite was derivatized with sulfonic groups to form sulfonic-functionalized GO (GO-SO(3)(-)) through four sulfonation routes: through amide formation between the carboxylic group of GO and amine of sulfanilic acid (AA-GO-SO(3)(-)), aryl diazonium reaction of sulfanilic acid (AD-GO-SO(3)(-)), amide formation between the carboxylic group of GO and amine of cysteamine and oxidation by H(2)O(2) (CA-GO-SO(3)(-)), and alkyl diazonium reaction of cysteamine and oxidation by H(2)O(2) (CD-GO-SO(3)(-)). Results of Fourier transform infrared spectroscopy and X-ray photoelectrospectrocopy showed that -SO(3)(-) groups were attached onto GO. Thermo gravimetric analysis showed that derivatization with sulfonic groups improved thermo stability of GO. X-ray diffraction results indicated that GO-SO(3)(-) had more ordered π-π stacking structure than the original GO. GO-SO(3)(-) and cationic polyelectrote, poly (diallyldimethylammoniumchloride) (PDDA) were adsorbed at indium tin oxide (ITO) glass surface through layer-by-layer assembling to form (GO-SO(3)(-)/PDDA)(n)/ITO multilayers. After tris-(2,2'-bipyridyl) ruthenium (II) dichloride (Ru(bpy)(3)(2+)) was incorporated into the multilayers, the obtained Ru(bpy)(3)(2+)/(GO-SO(3)(-)/PDDA)(n)/ITO electrodes can be used as electrochemiluminescence sensors for detection of organic amine with high sensitivity (limit of detection of 1 nM) and stability.

  11. Estimated pKa values for the environmentally relevant C1 through C8 perfluorinated sulfonic acid isomers.

    Science.gov (United States)

    Rayne, Sierra; Forest, Kaya

    2016-10-14

    In order to estimate isomer-specific acidity constants (pKa) for the perfluorinated sulfonic acid (PFSA) environmental contaminants, the parameterization method 6 (PM6) pKa prediction method was extensively validated against a wide range of carbon oxyacids and related sulfonic/sulfinic acids. Excellent pKa prediction performance was observed for the carbon oxyacids using the PM6 method, but this approach was found to have a severe positive bias for sulfonic/sulfinic acids. To overcome this obstacle, a correlation was developed between non-adjusted PM6 pKa values and the corresponding experimentally obtained/estimated acidity constants for a range of representative alkyl, aryl and halogen-substituted sulfonic acids. Application of this correction to the PM6 values allows for extension of this computational method to a new acid functional group. When used to estimate isomer-specific pKa values for the C1 through C8 PFSAs, the modified PM6 approach suggests an adjusted pKa range from -5.3 to -9.0, indicating that all members of this class of well-known environmental contaminants will be effectively completely dissociated in aquatic systems. PMID:27389973

  12. Synthesis of naphthoxazinone derivatives using silica-bonded -sulfonic acid as catalyst under solvent-free conditions

    Indian Academy of Sciences (India)

    Khodabakhsh Niknam; Parisa Abolpour

    2015-07-01

    Silica-bonded -sulfonic acid is employed as a recyclable catalyst for the synthesis of naphthoxazinone derivatives from the reaction of -naphthol, aromatic aldehydes and urea at 150°C under solvent-free conditions. The heterogeneous catalyst was recycled for five runs after the reaction of -naphthol, benzaldehyde and urea without losing its catalytic activity.

  13. Synthesis and properties of novel photosensitive poly(arylene ether sulfone) containing chalcone moiety in the main chain

    Energy Technology Data Exchange (ETDEWEB)

    Wen Pushan [Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, Hubei Province, South-Central University for Nationalities, Wuhan 430074 (China); Wang Lei [Department of Materials Physics and Chemistry, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Zhang Aiqing [Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, Hubei Province, South-Central University for Nationalities, Wuhan 430074 (China); Li Xiangdan, E-mail: xiangdanli@yahoo.com.cn [Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, Hubei Province, South-Central University for Nationalities, Wuhan 430074 (China); Lee, Myong-Hoon, E-mail: mhlee2@chonbuk.ac.kr [Department of Polymer/Nano Science and Technology, Chonbuk National University, Jeonju 561-756 (Korea, Republic of)

    2011-04-15

    Research highlights: {yields} A series of novel photosensitive poly(arylene ether sulfone)s (PAESs) containing chalcone moiety in the main chain have been successfully synthesized. {yields} The photo-crosslinking of polymer film was carried out under UV irradiation without photoinitiator. {yields} The resulting polymers showed good thermal stability and excellent chemical stability after crosslinking. - Abstract: A new series of photosensitive poly(arylene ether sulfone)s containing chalcone moiety in the main chain were synthesized from 4,4'-dihydroxychalcone (4DHC), 4,4'-difluorodiphenylsulfone (DFDPS) and bisphenol A (BPA). This series of polymers were characterized by {sup 1}H NMR, FT-IR, UV spectroscopy, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The polymers were stable up to 400 deg. C, which indicates that the polymers possess good thermal properties. The polymers were found to be soluble in polar solvents and chlorinated solvents. However, the polymers were insoluble in hydrocarbons and in hydroxyl group-containing solvents. After the irradiation of UV light, the thin polymer film was crosslinked to give an insoluble film in the absence of a photoinitiator or sensitizers. The rate of photocrosslinking was also examined and discussed.

  14. Reaction kinetics of free fatty acids esterification in palm fatty acid distillate using coconut shell biochar sulfonated catalyst

    Science.gov (United States)

    Hidayat, Arif; Rochmadi, Wijaya, Karna; Budiman, Arief

    2015-12-01

    Recently, a new strategy of preparing novel carbon-based solid acids has been developed. In this research, the esterification reactions of Palm Fatty Acid Distillate (PFAD) with methanol, using coconut shell biochar sulfonated catalyst from biomass wastes as catalyst, were studied. In this study, the coconut shell biochar sulfonated catalysts were synthesized by sulfonating the coconut shell biochar using concentrated H2SO4. The kinetics of free fatty acid (FFA) esterification in PFAD using a coconut shell biochar sulfonated catalyst was also studied. The effects of the mass ratio of catalyst to oil (1-10%), the molar ratio of methanol to oil (6:1-12:1), and the reaction temperature (40-60°C) were studied for the conversion of PFAD to optimize the reaction conditions. The results showed that the optimal conditions were an methanol to PFAD molar ratio of 12:1, the amount of catalyst of 10%w, and reaction temperature of 60°C. The proposed kinetic model shows a reversible second order reaction and represents all the experimental data satisfactorily, providing deeper insight into the kinetics of the reaction.

  15. Las revueltas populares en Ecuador

    Directory of Open Access Journals (Sweden)

    Francisco Hidalgo

    2002-01-01

    Full Text Available La historia de las sociedades latinoamericanas, desde sus inicios, ha estado marcada por las luchas populares. Es una historia escrita la más de las veces con la violencia que reclama el derecho a la vida. Es la historia de unos colectivos que se niegan, se resisten, a perder sus espacios. Siempre ha sido de esta manera, pero ya es tiempo de cambiar el presente por un futuro de auténtica justicia. El nuevo Milenio nos recibe con las ideologías de la globalización y del mercado único, con la exclusión social y la crisis económica; debemos reaccionar como un solo pueblo frente a esto, y para eso es necesario despertar y organizarnos desde nuestras unidades culturales a fin de vencer la voracidad del capitalismo neoliberal.

  16. Las Vegas Floodplain Management Study

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The City of Las Vegas and the Tierra y Montes Soil and Water Conservation District requested the Natural Resources Conservation Service (NRCS) to conduct a study of...

  17. Las fallas en los engranajes

    Directory of Open Access Journals (Sweden)

    Luis Eduardo Benitez Hernández

    2011-02-01

    Full Text Available En este artículo se presenta un resumen de la forma en que trabajan los engranajes de evolvenle haciendo énfasis en las caracteristicas de la rodadura y el deslizamiento que se suceden a través del engrane y su influencia en las fallas de los dientes. Se analizan las principales formas de falla, sus causas y la forma en que pueden ser evitadas. Este articulo es extractado del trabajo: Funcionamiento y análisis de fallas de los engranajes que fue presentado en las "Terceras Jornadas Nacionales sobre Mantenimiento" organizadas por ACIEM - Cundinamarca y obtuvo el segundo premio MVA a la Ingeniería de Mantenimiento.

  18. Improved oral absorption of cilostazol via sulfonate salt formation with mesylate and besylate

    Directory of Open Access Journals (Sweden)

    Seo JH

    2015-07-01

    Full Text Available Jae Hong Seo, Jung Bae Park, Woong-Kee Choi, Sunhwa Park, Yun Jin Sung, Euichaul Oh, Soo Kyung Bae College of Pharmacy and Integrated Research Institute of Pharmaceutical Sciences, The Catholic University of Korea, Bucheon, South Korea Objective: Cilostazol is a Biopharmaceutical Classification System class II drug with low solubility and high permeability, so its oral absorption is variable and incomplete. The aim of this study was to prepare two sulfonate salts of cilostazol to increase the dissolution and hence the oral bioavailability of cilostazol.Methods: Cilostazol mesylate and cilostazol besylate were synthesized from cilostazol by acid addition reaction with methane sulfonic acid and benzene sulfonic acid, respectively. The salt preparations were characterized by nuclear magnetic resonance spectroscopy. The water contents, hygroscopicity, stress stability, and photostability of the two cilostazol salts were also determined. The dissolution profiles in various pH conditions and pharmacokinetic studies in rats were compared with those of cilostazol-free base.Results: The two cilostazol salts exhibited good physicochemical properties, such as nonhygroscopicity, stress stability, and photostability, which make it suitable for the preparation of pharmaceutical formulations. Both cilostazol mesylate and cilostazol besylate showed significantly improved dissolution rate and extent of drug release in the pH range 1.2–6.8 compared to the cilostazol-free base. In addition, after oral administration to rats, cilostazol mesylate and cilostazol besylate showed increases in Cmax and AUCt of approximately 3.65- and 2.87-fold and 3.88- and 2.94-fold, respectively, compared to cilostazol-free base.Conclusion: This study showed that two novel salts of cilostazol, such as cilostazol mesylate and cilostazol besylate, could be used to enhance its oral absorption. The findings warrant further preclinical and clinical studies on cilostazol mesylate and

  19. Las palabras y el escrito

    OpenAIRE

    Cassany, Daniel

    2004-01-01

    Uno de los problemas habituales al que deben enfretarse los aprendices que se inician en la lectura es la presencia reiterada en los textos de palabras nuevas o desconocidas que dificultan la comprensi??n del contenido del escrito. En este art??culo nos proponemos comparar las actitudes y las habilidades que utilizan lectores expertos y aprendices ante esta situaci??n, que consideramos bastante corriente para cualquier tipo de lector y lectura.

  20. Sulfonation of 17β-estradiol and inhibition of sulfotransferase activity by polychlorobiphenylols and celecoxib in channel catfish, Ictalurus punctatus

    International Nuclear Information System (INIS)

    The sulfonation of 17β-estradiol (E2) by human liver and recombinant sulfotransferases is influenced by environmental contaminants such as hydroxylated metabolites of polychlorinated biphenyls (OH-PCBs), which are potent inhibitors, and the therapeutic drug, celecoxib, which affects positional sulfonation of E2. In some locations, the aquatic environment is contaminated by PCBs, OH-PCBs and widely used therapeutic drugs. The objectives of this study were to investigate the sulfonation kinetics of E2 in liver cytosol from channel catfish (Ictalurus punctatus); to examine the effect of OH-PCBs on E2 sulfonation; and to determine if celecoxib altered the position of E2 sulfonation, as it does with human liver cytosol. E2 was converted to both 3- and 17-sulfates by catfish liver cytosol. At E2 concentrations below 1μM, formation of E2-3-sulfate (E2-3-S) predominated, but substrate inhibition was observed at higher concentrations. Rates of E2-3-S formation at different E2 concentrations were fit to a substrate inhibition model, with K'm and V'max values of 0.40+/-0.10μM and 91.0+/-4.7pmol/min/mg protein, respectively and Ki of 1.08+/-0.09μM. The formation of E2-17-S fit Michaelis-Menten kinetics over the concentration range 25nM to 2.5μM, with Km and Vmax values of 1.07+/-0.23μM and 25.7+/-4.43pmol/min/mg protein, respectively. The efficiency (Vmax/Km) of formation of E2-3-S was 9.8-fold higher than that of E2-17-S. Several OH-PCBs inhibited E2 3-sulfonation, measured at an E2 concentration of 1nM. Of those tested, the most potent inhibitor was 4'-OH-CB79, with two chlorine atoms flanking the OH group (IC50: 94nM). The inhibition of estrogen sulfonation by OH-PCBs may disrupt the endocrine system and thus contribute to the known toxic effects of these compounds. Celecoxib did not stimulate E2-17-S formation, as is the case with human liver cytosol, but did inhibit the formation of E2-3-S (IC50: 44μM) and to a lesser extent, E2-17-S (IC50: >160μM), suggesting the

  1. Estudio sobre los usos de las TIC y las posibilidades de empoderamiento en las mujeres

    OpenAIRE

    Rubio Hurtado, María José; Escofet Roig, Anna

    2013-01-01

    El empoderamiento es un proceso de adquisición de poder de las personas que se encuentran en situación de desigualdad respecto a otras, en algunos casos de forma colectiva y en otros individual, para tomar decisiones acerca de su vida, ser partícipes y realizar cambios positivos en ésta. La medida del empoderamiento en relación a las Tecnologías de la Información y la Comunicación es difícil ya que implica analizar las habilidades, el conocimiento, el acceso y el uso de dichas tecnologías. Es...

  2. Tendencias organizacionales de las empresas.

    Directory of Open Access Journals (Sweden)

    Derlisiret Rincón M.

    2002-01-01

    Full Text Available El propósito de este trabajo es analizar la evolución de los modelos organizacionales utilizados por las empresas durante los siglos XX y XXI, a la vez que se intenta establecer las posibles tendencias para las empresas del futuro. Para ello, se caracterizan los modelos con base en la clasificación correspondiente a las visiones: mecanicista, naturista y ecologista de la organización. En tal sentido, se realiza una investigación descriptiva-documental a partir de la revisión de importantes aportes sobre las nuevas formas organizacionales, evolución y principios de las empresas. Los resultados revelan que la supervivencia de una empresa en contextos turbulentos como los actuales dependerá de variables como: rapidez, calidad, eficiencia, espontaneidad, desestandarización, flexibilidad e innovación. Se concluye que la tendencia es a la ausencia de estructuras organizacionales, formales y rígidas.

  3. Andrographolide sulfonate ameliorates lipopolysaccharide-induced acute lung injury in mice by down-regulating MAPK and NF-κB pathways.

    Science.gov (United States)

    Peng, Shuang; Hang, Nan; Liu, Wen; Guo, Wenjie; Jiang, Chunhong; Yang, Xiaoling; Xu, Qiang; Sun, Yang

    2016-05-01

    Acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) is a severe, life-threatening medical condition characterized by widespread inflammation in the lungs, and is a significant source of morbidity and mortality in the patient population. New therapies for the treatment of ALI are desperately needed. In the present study, we examined the effect of andrographolide sulfonate, a water-soluble form of andrographolide (trade name: Xi-Yan-Ping Injection), on lipopolysaccharide (LPS)-induced ALI and inflammation. Andrographolide sulfonate was administered by intraperitoneal injection to mice with LPS-induced ALI. LPS-induced airway inflammatory cell recruitment and lung histological alterations were significantly ameliorated by andrographolide sulfonate. Protein levels of pro-inflammatory cytokines in bronchoalveolar lavage fluid (BALF) and serum were reduced by andrographolide sulfonate administration. mRNA levels of pro-inflammatory cytokines in lung tissue were also suppressed. Moreover, andrographolide sulfonate markedly suppressed the activation of mitogen-activated protein kinase (MAPK) as well as p65 subunit of nuclear factor-κB (NF-κB). In summary, these results suggest that andrographolide sulfonate ameliorated LPS-induced ALI in mice by inhibiting NF-κB and MAPK-mediated inflammatory responses. Our study shows that water-soluble andrographolide sulfonate may represent a new therapeutic approach for treating inflammatory lung disorders. PMID:27175331

  4. Andrographolide sulfonate ameliorates lipopolysaccharide-induced acute lung injury in mice by down-regulating MAPK and NF-κB pathways

    Directory of Open Access Journals (Sweden)

    Shuang Peng

    2016-05-01

    Full Text Available Acute lung injury (ALI or acute respiratory distress syndrome (ARDS is a severe, life-threatening medical condition characterized by widespread inflammation in the lungs, and is a significant source of morbidity and mortality in the patient population. New therapies for the treatment of ALI are desperately needed. In the present study, we examined the effect of andrographolide sulfonate, a water-soluble form of andrographolide (trade name: Xi-Yan-Ping Injection, on lipopolysaccharide (LPS-induced ALI and inflammation. Andrographolide sulfonate was administered by intraperitoneal injection to mice with LPS-induced ALI. LPS-induced airway inflammatory cell recruitment and lung histological alterations were significantly ameliorated by andrographolide sulfonate. Protein levels of pro-inflammatory cytokines in bronchoalveolar lavage fluid (BALF and serum were reduced by andrographolide sulfonate administration. mRNA levels of pro-inflammatory cytokines in lung tissue were also suppressed. Moreover, andrographolide sulfonate markedly suppressed the activation of mitogen-activated protein kinase (MAPK as well as p65 subunit of nuclear factor-κB (NF-κB. In summary, these results suggest that andrographolide sulfonate ameliorated LPS-induced ALI in mice by inhibiting NF-κB and MAPK-mediated inflammatory responses. Our study shows that water-soluble andrographolide sulfonate may represent a new therapeutic approach for treating inflammatory lung disorders.

  5. Improving the Efficacy of Conventional Therapy by Adding Andrographolide Sulfonate in the Treatment of Severe Hand, Foot, and Mouth Disease: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Xiuhui Li

    2013-01-01

    Full Text Available Background. Herb-derived compound andrographolide sulfonate (called Xiyanping injection recommended control measure for severe hand, foot, and mouth disease (HFMD by the Ministry of Health (China during the 2010 epidemic. However, there is a lack of good quality evidence directly comparing the efficacy of Andrographolide Sulfonate combination therapy with conventional therapy. Methods. 230 patients were randomly assigned to 7–10 days of Andrographolide Sulfonate 5–10 mg/Kg/day and conventional therapy, or conventional therapy alone. Results. The major complications occurred less often after Andrographolide Sulfonate (2.6% versus 12.1%; risk difference [RD], 0.94; 95% CI, 0.28–1.61; P=0.006. Median fever clearance times were 96 hours (CI, 80 to 126 for conventional therapy recipients and 48 hours (CI, 36 to 54 for Andrographolide Sulfonate combination-treated patients (χ2=16.57, P<0.001. The two groups did not differ in terms of HFMD-cause mortality (P=1.00 and duration of hospitalization (P=0.70. There was one death in conventional therapy group. No important adverse event was found in Andrographolide Sulfonate combination therapy group. Conclusions. The addition of Andrographolide Sulfonate to conventional therapy reduced the occurrence of major complications, fever clearance time, and the healing time of typical skin or oral mucosa lesions in children with severe HFMD.

  6. Synthesis and detection of N-sulfonated oversulfated chondroitin sulfate in marketplace heparin.

    Science.gov (United States)

    Mans, Daniel J; Ye, Hongping; Dunn, Jamie D; Kolinski, Richard E; Long, Dianna S; Phatak, Nisarga L; Ghasriani, Houman; Buhse, Lucinda F; Kauffman, John F; Keire, David A

    2015-12-01

    N-sulfonated oversulfated chondroitin sulfate (NS-OSCS), recently reported as a potential threat to the heparin supply, was prepared along with its intermediate derivatives. All compounds were spiked into marketplace heparin and subjected to United States Pharmacopeia (USP) identification assays for heparin (proton nuclear magnetic resonance [(1)H NMR], chromatographic identity, % galactosamine [%GalN], anti-factor IIa potency, and anti-factor Xa/IIa ratio). The U.S. Food and Drug Administration (FDA) strong-anionic exchange high-performance liquid chromatography (SAX-HPLC) method resolved NS-OSCS from heparin and OSCS and had a limit of detection of 0.26% (w/w) NS-OSCS. The %GalN test was sensitive to the presence of NS-OSCS in heparin. Therefore, current USP heparin monograph tests (i.e., SAX-HPLC and %GalN) detect the presence of NS-OSCS in heparin.

  7. Effect of Sulfonation of SEBS Copolymer on the physicochemical properties of Proton Exchange Membrane

    Directory of Open Access Journals (Sweden)

    Alvaro Realpe

    2015-08-01

    Full Text Available In this work, proton exchange membranes were prepared using SEBS copolymer, for application in a fuel cell. The SEBS copolymer was modified with the addition of a TiO2 load to prepare sulfonated and unmodified membranes. The sulfonated–loaded membrane exhibited higher values of water absorption (16% and ion exchange capacity (1.13 meq/g due to a significant increase in porosity, which increased the surface area and facilitated the ion exchange phenomenon by the formation of complexes between the sulfuric acid and TiO2; however, the low stability of the membrane prevented the applications of impedance and mechanical testing. The membranes were analyzed by Fourier transform infrared spectroscopy (FTIR, to check the modification of the SEBS; however, there were no bands that will determine the presence of TiO2 in the copolymer.

  8. Evaluation of sodium lignin sulfonate as draw solute in forward osmosis for desert restoration

    KAUST Repository

    Duan, Jintang

    2014-03-01

    Sodium lignin sulfonate (NaLS), an abundant waste product of paper manufacturing, can be used in desert restoration. Combined with water and applied on arid land, NaLS has been shown to stabilize sand and provide a medium for plant growth. Here, we demonstrate that NaLS is an efficient draw solute in forward osmosis (FO) to extract water from impaired sources. The osmotic pressure of a 600. g. NaLS/kg water solution is 78. bar (7.8 MPa) as measured by freezing point depression. The FO performance using NaLS draw solute was evaluated with commercial FO membranes under various test conditions. The effects of draw solute concentration, feed salinity and membrane orientation were systematically investigated. Potential ways to optimize the process, e.g. combining fertilizer draw solutes and NaLS, are proposed. © 2013 Elsevier B.V.

  9. EPR study of gamma irradiated DL-methionine sulfone single crystals

    Science.gov (United States)

    Karabulut, Bünyamin; Yıldırım, İlkay

    2015-12-01

    Electron paramagnetic resonance (EPR) study of gamma irradiated dl-2-amino-4-(Methylsulfonyl) butyric acid (dl-methionine sulfone, hereafter dl-ABA) single crystals and powder was performed at room temperature. It has been found that this compound indicates the existence of C. O2- and N. H2 radicals after γ-irradiation. While g and hyperfine splitting values for the N. H2 radical were observed, for the C. O2- radical, only the g factor was measured. The EPR spectra have shown that N. H2 radical has two groups each having two distinct sites and C. O2- radical has one site. The principal g and hyperfine values for all sites were analyzed.

  10. Cluster Morphology-Polymer Dynamics Correlations in Sulfonated Polystyrene Melts: Computational Study

    Science.gov (United States)

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

    2016-04-01

    Reaching exceptionally long times up to 500 ns in equilibrium and nonequilibrium molecular dynamics simulations studies, we have attained a fundamental molecular understanding of the correlation of ionomer clusters structure and multiscale dynamics, providing new insight into one critical, long-standing challenge in ionic polymer physics. The cluster structure in melts of sulfonated polystyrene with Na+ and Mg2 + counterions are resolved and correlated with the dynamics on multiple length and time scales extracted from measurements of the dynamic structure factor and shear rheology. We find that as the morphology of the ionic clusters changes from ladderlike for Na+ to disordered structures for Mg2 + , the dynamic structure factor is affected on the length scale corresponding to the ionic clusters. Rheology studies show that the viscosity for Mg2 + melts is higher than for Na+ ones for all shear rates, which is well correlated with the larger ionic clusters' size for the Mg2 + melts.

  11. Improved Performance of Sulfonated Polyarylene Ethers for Proton Exchange Membrane Fuel Cell

    Institute of Scientific and Technical Information of China (English)

    D. Xing; J. Kerres; F. Sch(o)nberger

    2005-01-01

    @@ 1Introduction The proton exchange membrane (PEM) is one of key components in fuel cell system. Its properties are very important in determining PEMFC performance. The membranes presently used in fuel cell are perfluorosulfonic polymers, such as Nafion(R) from Dupont. Although they have high proton conductivity and excellent chemical stability, their too high production cast and methanol permeability lead to failure of fuel cell application. Therefore, various partially fluorinated and non-fluorinated polymer electrolytes are under development for PEMFC application since one decade. In the middle of non-fluorinated polymer electrolytes, sulfonated poly(arylene ether)s display high thermal stability, good mechanical properties and exceptional resistance to oxidation and acid catalyzed hydrolysis. They have been regarded as well-suited proton exchange membrane candidates for fuel cells.

  12. Synthesis and detection of N-sulfonated oversulfated chondroitin sulfate in marketplace heparin.

    Science.gov (United States)

    Mans, Daniel J; Ye, Hongping; Dunn, Jamie D; Kolinski, Richard E; Long, Dianna S; Phatak, Nisarga L; Ghasriani, Houman; Buhse, Lucinda F; Kauffman, John F; Keire, David A

    2015-12-01

    N-sulfonated oversulfated chondroitin sulfate (NS-OSCS), recently reported as a potential threat to the heparin supply, was prepared along with its intermediate derivatives. All compounds were spiked into marketplace heparin and subjected to United States Pharmacopeia (USP) identification assays for heparin (proton nuclear magnetic resonance [(1)H NMR], chromatographic identity, % galactosamine [%GalN], anti-factor IIa potency, and anti-factor Xa/IIa ratio). The U.S. Food and Drug Administration (FDA) strong-anionic exchange high-performance liquid chromatography (SAX-HPLC) method resolved NS-OSCS from heparin and OSCS and had a limit of detection of 0.26% (w/w) NS-OSCS. The %GalN test was sensitive to the presence of NS-OSCS in heparin. Therefore, current USP heparin monograph tests (i.e., SAX-HPLC and %GalN) detect the presence of NS-OSCS in heparin. PMID:26278168

  13. Dynamic interfacial behavior of decyl methylnaphthalene sulfonate surfactants for enhanced oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Zhongkui; Ba Yan; Li Zongshi; Qiao Weihong; Cheng Luebai [State Key Lab. of Fine Chemicals, Dalian Univ. of Technology, Dalian (China)

    2004-10-01

    The high purity decyl methylnaphthalene sulfonate (DMNS) was synthesized, the purity was determined by HPLC and the structure was confirmed by IR, UV and ESI-MS. Dynamic interfacial tensions (DIT) between DMNS flooding systems and crude oil were measured and the effects of sodium carbonate concentration, surfactant concentration and sodium chloride concentration on the DIT behaviors were investigated. It's found that the surfactant concentration, alkali concentration and the salinity have obvious influences on DIT behaviors. DMNS possessed outstanding capacity and efficiency of lowering the DIT between oil and water. The minimum dynamic interfacial tension could reach 6.35 x 10{sup -6} mNm{sup -1} at a low concentration for added surfactant. DMNS might be used in Enhanced Oil Recovery with low costs and high efficiency. (orig.)

  14. Comparison of gene expression methods to identify genes responsive to perfluorooctane sulfonic acid.

    Science.gov (United States)

    Hu, Wenyue; Jones, Paul D; Decoen, Wim; Newsted, John L; Giesy, John P

    2005-01-01

    Genome-wide expression techniques are being increasingly used to assess the effects of environmental contaminants. Oligonucleotide or cDNA microarray methods make possible the screening of large numbers of known sequences for a given model species, while differential display analysis makes possible analysis of the expression of all the genes from any species. We report a comparison of two currently popular methods for genome-wide expression analysis in rat hepatoma cells treated with perfluorooctane sulfonic acid. The two analyses provided 'complimentary' information. Approximately 5% of the 8000 genes analyzed by the GeneChip array, were altered by a factor of three or greater. Differential display results were more difficult to interpret, since multiple gene products were present in most gel bands so a probabilistic approach was used to determine which pathways were affected. The mechanistic interpretation derived from these two methods was in agreement, both showing similar alterations in a specific set of genes. PMID:21783471

  15. Sawdust Ash as Powder Material for Self-Compacting Concrete Containing Naphthalene Sulfonate

    Directory of Open Access Journals (Sweden)

    Augustine U. Elinwa

    2014-01-01

    Full Text Available Tests are carried out to determine the fluidity of Ashaka Portland cement paste and its compatibility with sawdust ash (SDA as powder material for self-compacting cement (SCC mixtures. Results of the investigation showed that saturation was achieved at w/c ratios of 0.4 and 0.42, at dosages of naphthalene sulfonate superplasticizers of 3.5% and 2%, respectively. The optimum replacement level for the SCC mixture was 10 wt.% of cement by SDA and 2% of the superplasticizer dosage. The achieved spread and flow time were 26 cm and 8 seconds and are within the specified range of 24 cm to 26 cm and 7 to 11 seconds, respectively. Statistical inference showed that the mix, w/c, and the interaction between the mix and w/c ratio are significant.

  16. 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...... radical attack to the otherwise flexible SO(2) PBI membranes. Steady phosphoric acid doping of the cross-linked membranes was achieved at elevated temperatures with little swelling. The acid-doped membranes exhibited increased mechanical strength compared to both pristine SO(2) PBI and poly[2,2'-(m......-phenylene)-5,5'-bibenzimidazole] (mPBI). The superior characteristics of the cross-linked SO(2) PBI membranes allowed higher acid doping levels and, therefore, higher proton conductivity. Fuel-cell tests with the cross-linked membranes demonstrated a high open circuit voltage and improved power performance...

  17. Selective Preparation of Furfural from Xylose over Sulfonic Acid Functionalized Mesoporous Sba-15 Materials

    Directory of Open Access Journals (Sweden)

    Panpan Li

    2011-04-01

    Full Text Available Sulfonic acid functionalized mesoporous SBA-15 materials were prepared using the co-condensation and grafting methods, respectively, and their catalytic performance in the dehydration of xylose to furfural was examined. SBA-15-SO3H(C prepared by the co-condensation method showed 92–95% xylose conversion and 74% furfural selectivity, and 68–70% furfural yield under the given reaction conditions. The deactivation and regeneration of the SBA-15-SO3H(C catalyst for the dehydration of xylose was also investigated. The results indicate that the used and regeneration catalysts retained the SBA-15 mesoporous structure, and the S content of SBA-15-SO3H(C almost did not change. The deactivation of the catalysts is proposed to be associated with the accumulation of byproducts, which is caused by the loss reaction of furfural. After regeneration by H2O2, the catalytic activity of the catalyst almost recovered.

  18. SYNTHESIS, STRUCTURE AND PROPERTIES OF INTERPENETRATING SULFONIC ACID RESINS WITH HIGH CAPACITY

    Institute of Scientific and Technical Information of China (English)

    XU Hede; LI Guoming

    1989-01-01

    Two series of interpenetrating sulfonic acid resins (ISAR), 10 × n and n × 10 ,were prepared by means of the wet method, and the physicochemical, thermodynamic and kinetic properties of the ISAR were measured . The results show: 10 × n resins exhibit better properties than n × 10 ones ,mainly in higher apparent degree of crosslinking and larger conformational entropy effect, among which , 10 × 1 resin exhibits the best thermodynamic and kinetic properties. In the DTA graphs of n × 10 resins, there are two Tg and two Tox, but in those of 10 × n, only one Tg and one Tox . This result well supports the conclusion that 10 × n resins have much better interpenetrating structural aspects.

  19. Metabolic fingerprint of dimethyl sulfone (DMSO2) in microbial-mammalian co-metabolism.

    Science.gov (United States)

    He, Xuan; Slupsky, Carolyn M

    2014-12-01

    There is growing awareness that intestinal microbiota alters the energy harvesting capacity of the host and regulates metabolism. It has been postulated that intestinal microbiota are able to degrade unabsorbed dietary components and transform xenobiotic compounds. The resulting microbial metabolites derived from the gastrointestinal tract can potentially enter the circulation system, which, in turn, affects host metabolism. Yet, the metabolic capacity of intestinal microbiota and its interaction with mammalian metabolism remains largely unexplored. Here, we review a metabolic pathway that integrates the microbial catabolism of methionine with mammalian metabolism of methanethiol (MT), dimethyl sulfide (DMS), and dimethyl sulfoxide (DMSO), which together provide evidence that supports the microbial origin of dimethyl sulfone (DMSO2) in the human metabolome. Understanding the pathway of DMSO2 co-metabolism expends our knowledge of microbial-derived metabolites and motivates future metabolomics-based studies on ascertaining the metabolic consequences of intestinal microbiota on human health, including detoxification processes and sulfur xenobiotic metabolism.

  20. Demarcation of mutant-carrying regions in barley plants after ethylmethane-sulfonate seed treatment

    DEFF Research Database (Denmark)

    Jacobsen, P.

    1966-01-01

    The branching pattern of the barley plant is analyzed and the anatomical structure of the resting barley embryo studied in longitudinal and cross-sections as well as by dissection techniques. The frequency and distribution of ethylmethane-sulfonate induced chloroplast and morphological seedling...... present in the embryo of the seed. These will, however, not appear in plants under normal development.There are, according to the present analysis, 6 spikes for which 1 or 2 functional initial cells for their sporogenous tissue are already established in the embryo, i.e. at the time of mutagenic treatment...... mutants were analyzed in spikes classified according to their ontogenetic relationship. The frequency with which two spikes segregated identical mutants was determined by pairwise comparisons of all spikes in each plant. In this way the frequency of mutant cluster sharing between spikes and spike groups...

  1. Polybenzimidazole and sulfonated polyhedral oligosilsesquioxane composite membranes for high temperature polymer electrolyte membrane fuel cells

    International Nuclear Information System (INIS)

    Composite membranes based on poly(2,2′(m-phenylene)-5,5′bibenzimidazole) (PBI) and sulfonated polyhedral oligosilsesquioxane (S-POSS) with S-POSS contents of 5 and 10 wt.% were prepared by solution casting as base materials for high temperature polymer electrolyte membrane fuel cells. With membranes based on pure PBI as a reference point, the composite membranes were characterized with respect to spectroscopic and physicochemical properties. After doping with phosphoric acid, the composite membranes showed considerably improved ex situ proton conductivity under anhydrous as well as under fully humidified conditions in the 120-180 °C temperature range. The conductivity improvements were also confirmed by in situ fuel cell tests at 160 °C and further supported by the electrochemical impedance spectroscopy data based on the operating membrane electrode assemblies, demonstrating the technical feasibility of the novel electrolyte materials

  2. Nanoscale Distribution of Sulfonic Acid Groups Determines Structure and Binding of Water in Nafion Membranes

    Science.gov (United States)

    Ling, Xiao; Bonn, Mischa

    2016-01-01

    Abstract The connection between the nanoscale structure of two chemically equivalent, yet morphologically distinct Nafion fuel‐cell membranes and their macroscopic chemical properties is demonstrated. Quantification of the chemical interactions between water and Nafion reveals that extruded membranes have smaller water channels with a reduced sulfonic acid head group density compared to dispersion‐cast membranes. As a result, a disproportionally large amount of non‐bulk water molecules exists in extruded membranes, which also exhibit larger proton conductivity and larger water mobility compared to cast membranes. The differences in the physicochemical properties of the membranes, that is, the chemical constitution of the water channels and the local water structure, and the accompanying differences in macroscopic water and proton transport suggest that the chemistry of nanoscale channels is an important, yet largely overlooked parameter that influences the functionality of fuel‐cell membranes. PMID:26895211

  3. Meso- and macroporous sulfonated starch solid acid catalyst for esterification of palm fatty acid

    Directory of Open Access Journals (Sweden)

    Ibrahim M. Lokman

    2016-03-01

    Full Text Available In the present work, a heterogeneous solid acid catalyst was successfully developed from starch. The catalyst was prepared by a significant two-step process; the initial step was incomplete carbonization of starch (ICS at 400 °C for 12 h and consequently followed by sulfonation process using concentrated H2SO4 to produce sulfonated-incomplete carbonized starch (ICS-SO3H. The characterization of the ICS-SO3H catalyst was done for chemical and physical properties such as X-ray diffraction (XRD, ammonia-temperature programmed desorption (NH3-TPD, surface area analysis, thermal gravimetric analysis (TGA, elemental analysis and morphology analysis by scanning electron microscope (SEM. BET results showed the structure of ICS-SO3H consists of meso- and macro-porous properties, which allowed high density of the SO3H group attached on its carbon networks. The catalytic activity of ICS-SO3H catalyst was determined by analyzing the catalyst performance to esterify palm fatty acid distillate (PFAD and sequentially produced methyl ester. The maximum free fatty acid (FFA conversion and FAME yield were as high as 94.6% and 90.4%, respectively, at 75 °C using 10:1 methanol-to-PFAD molar ratio and 2 wt.% of catalyst within 3 h. The catalyst has sufficient potential to recycle up to 6 reactions without reactivation step and any remarkable loss of catalytic activity. It revealed that the heterogeneous ICS-SO3H catalyst exhibits high stability, reusability and catalytic activity.

  4. Dynamic interfacial tension behavior of alkyl amino sulfonate in crude oil-brine system

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Zhao Hua; Luo, Yue [Yangtze Univ., Jingzhou, Hubei (China). College of Chemistry and Environmental Engineering

    2013-09-15

    The compatibility of surfactants, a series of alkyl amino sulfonate containing various the length of alkyl chain (dodecyl, tetradecyl, hexadecyl and octadecyl, developed in our laboratory), with formation water matching the Xinjiang Oil Field reservoir water and the dynamic interfacial tensions (DIT) behaviors between the crude oil and the formation water for a number of alkaline flooding systems were measured. These surfactants are found to be well compatible with formation water up to 0.10g L{sup -1} surfactant concentration, especially Dodec-AS and Tetradec-AS show a good compatibility with formation water over the full range of surfactant concentration investigated (0.01-0.20g L{sup -1}). All surfactants exhibit the dynamic interfacial tension behavior, and can reach and maintain low interfacial tension at very low concentration. The time for reaching the equilibrium DIT (DIT{sub eq}) is longer for surfactant with stronger lipophilicity, e.g. octadecyl-AS. It is interestingly found that the ratio value between DIT{sub eq} and the tension at crude oil/reservoir water interface in the absence of surfactant is in the range of 10{sup -4}-10{sup -3} mN m{sup -1}, accordingly based on which and the previous results, four surfactants individually or with other additives together may become potent candidates for enhanced oil recovery. Fortunately, the alkyl amino sulfonate combinational systems without alkali designed by our group can reduce the interfacial tension even to 10{sup -4} mN m{sup -1} at very low surfactant concentration. These surfactants or their systems have characteristic of 'Green', in addition to the excellent salt-tolerance and the less expensive cost for enhanced oil recovery, and therefore they are good oil-displacing reagents for enhanced oil recovery. (orig.)

  5. Stability of 6:2 fluorotelomer sulfonate in advanced oxidation processes: degradation kinetics and pathway.

    Science.gov (United States)

    Yang, Xiaoling; Huang, Jun; Zhang, Kunlun; Yu, Gang; Deng, Shubo; Wang, Bin

    2014-03-01

    Perfluorooctane sulfonate (PFOS), a widely used mist suppressant in hard chrome electroplating industry, has been listed in the Stockholm Convention for global ban. 6:2 Fluorotelomer sulfonate (6:2 FTS) acid and salts have been adopted as alternative products in the market, but no data about their abiotic degradation has been reported. In the present study, the degradability of 6:2 FTS potassium salt (6:2 FTS-K) was evaluated under various advanced oxidation processes, including ultraviolet (UV) irradiation, UV with hydrogen peroxide (H2O2), alkaline ozonation (O3, pH = 11), peroxone (O3/H2O2), and Fenton reagent oxidation (Fe(2+)/H2O2). UV/H2O2 was found to be the most effective approach, where the degradation of 6:2 FTS-K followed the pseudo-first-order kinetics. The intermediates were mainly shorter chain perfluoroalkyl carboxylic acid (C7 to C2), while sulfate (SO4 (2-)) and fluoride (F(-)) were found to be the final products. The high yields of SO4 (2-) and F(-) indicate that 6:2 FTS-K can be nearly completely desulfonated and defluorinated under UV/H2O2 condition. The degradation should firstly begin with the substitution of hydrogen atom by hydroxyl radicals, followed by desulfonation, carboxylation, and sequential "flake off" of CF2 unit. Compared with PFOS which is inert in most advanced oxidation processes, 6:2 FTS-K is more degradable as the alternative.

  6. Study on Novel HIGEE Technology for Synthesis of Overbased Petroleum Sulfonate Detergent

    Institute of Scientific and Technical Information of China (English)

    Luo Lailong; Zhang Youlin; Bai Shengjun; Qian Zheng; Wu Wei; Chu Guangwen

    2006-01-01

    An innovative idea was proposed to prepare the overbased nano-sized calcium carbonate-calcium petroleum sulfonate in-situ the HIGEE reactor. The test sample prepared by this technology could meet the requirement of the industry standard SH0042-91 for the first-grade product on a par with similar overseas product. The test results obtained upon observation under microscope after freezing etching of specimen revealed that the crystal size of colloidal calcium sulfonate was in the range of 10-30 nm with an average size of 20 nm. The size of the detergent additive was uniform with good transmittance and fluidity. The HIGEE technology possesses five specific features as shown below: Firstly, the carbonation reaction is completed in one step with the reaction time reduced by more than 50% as compared to traditional batch reactor process along with enhanced reaction efficiency, good operability of the process and stabilized product quality. Secondly,ammonia emitted from the reaction is used as the co- promoter without the need for adding ammonia and water as promoters to simplify the promoter system along with effective and strong coupling of reactions. Thirdly, the utilization rate of Ca(OH)2 and CO2 is increased by 15% and 30%, respectively, with product yield increased by 15%, and calcium residue decreased by 65%. Fourthly, the HIGEE technology is environmental benign because of gasoline is used in this technology instead of toxic toluene and xylene. Fifthly, the dimension of HIGEE reactor is reduced by above two-thirds. The success in development of this new technology will offer new ideas and technology platform for the synthesis of metal detergent additive to lubricating oils in China.

  7. A verapamil electrochemical sensor based on magnetic mobile crystalline material-41 grafted by sulfonic acid

    International Nuclear Information System (INIS)

    Graphical abstract: The Fe2O3-MCM-41-SO3H was characterized with TEM and used to investigate the electrochemical behavior of verapamil. The results indicated that Fe2O3-MCM-41-SO3H-CPE facilitate the determination of verapamil with good sensitivity. Highlights: ► Electrooxidation of verapamil was performed using Fe2O3-MCM-41-SO3H-CPE. ► Modified electrode shows many advantages as a verapamil sensor. ► Excellent electrocatalytic activity was obtained for verapamil oxidation. ► The response of the modified electrode is linear over the entire 50–160 and 160–350 nM. -- Abstract: Magnetic (Fe2O3) mobile crystalline material-41 (MCM-41) grafted by sulfonic acid (Fe2O3-MCM-41-SO3H) was prepared and characterized using transmission electron microscopy (TEM) and nitrogen adsorption–desorption techniques. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) and square wave voltametry (SQWV) used to investigate the electrochemical behavior of verapamil at the sulfonic acid functionalized magnetic mesoporous silica, which was modified through carbon paste electrode (Fe2O3-MCM-41-SO3H-CPE). The Fe2O3-MCM-41-SO3H-CPE showed better performance for the electrochemical oxidation of verapamil, when compared with bare carbon paste electrode (CPE) and Fe2O3-MCM-41-CPE. The experimental conditions influencing the determination of verapamil were optimized and under optimal conditions, the oxidation peak current was proportional to verapamil concentration in the range of 50–160 and 160–350 nmol dm−3, while the detection limit was 41 nmol dm−3 (S/N = 3). The proposed method was successfully applied to determine verapamil in human serum, yielding satisfactory results. The spiked recoveries were in the range of (94.5–104.1%)

  8. Chemical Mechanical Polishing of Glass Substrate with α-Alumina-g-Polystyrene Sulfonic Acid Composite Abrasive

    Institute of Scientific and Technical Information of China (English)

    LEI Hong; BU Naijing; ZHANG Zefang; CHEN Ruling

    2010-01-01

    Abrasive is the one of key influencing factors during chemical mechanical polishing(CMP) process. Currently, α-Alumina (α-Al2O3) particle, as a kind of abrasive, has been widely used in CMP slurries, but their high hardness and poor dispersion stability often lead to more surface defects. After being polished with composite particles, the surface defects of work pieces decrease obviously. So the composite particles as abrasives in slurry have been paid more attention. In order to reduce defect caused by pure α-Al2O3 abrasive, α-alumina-g-polystyrene sulfonic acid (α-Al2O3-g-PSS) composite abrasive was prepared by surface graft polymerization. The composition, structure and morphology of the product were characterized by Fourier transform infrared spectroscopy(FTIR), X-ray photoelectron spectroscopy(XPS), time-of-flight secondary ion mass spectroscopy(TOF-SIMS), and scanning electron microscopy(SEM), respectively. The results show that polystyrene sulfonic acid grafts onto α-Al2O3, and has well dispersibility. Then, the chemical mechanical polishing performances of the composite abrasive on glass substrate were investigated with a SPEEDFAM-16B-4M CMP machine. Atomic force microscopy(AFM) images indicate that the average roughness of the polished glass substrate surface can be decreased from 0.835 nm for pure α-Al2O3 abrasive to 0.583 nm for prepared α-Al2O3-g-PSS core-shell abrasive. The research provides a new and effect way to improve the surface qualities during CMP.

  9. The corrosion inhibition of aluminum and its copper alloys in 1.0 M H{sub 2}SO{sub 4} solution using linear-sodium dodecyl benzene sulfonate as inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Abd El Rehim, Sayed S.; Amin, Mohammed A. [Chemistry Department, Faculty of Science, Ain Shams University, Abbassia, Cairo (Egypt); Moussa, S.O. [Chemistry Department, Faculty of Science, Ain Shams University, Abbassia, Cairo (Egypt)], E-mail: sherif_m74@yahoo.com; Ellithy, Abdallah S. [Chemistry Department, Faculty of Science, Ain Shams University, Abbassia, Cairo (Egypt)

    2008-12-20

    The corrosion inhibition of Al and its two copper alloys are the subject of tremendous technological importance due to the increased industrial applications of these materials. This paper reports the results of potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) measurements on the corrosion inhibition of Al (Al-2.5% Cu and Al-7.0% Cu) alloys in 1.0 M H{sub 2}SO{sub 4} solution carried out in different concentrations of linear-sodium dodecyl benzene sulfonate as an anionic surfactant (LAS) and temperature range from 10 to 60 deg. C. The data revealed that the inhibition efficiency increases with increasing surfactant concentration and time of immersion, and decreases with solution temperature. Energy dispersion X-ray (EDX) observations of the electrode surface confirmed the existence of LAS adsorbed film on the electrode surface. The surfactant acted mainly as cathodic inhibitor. Maximum inhibition efficiency of the surfactant is observed at concentration around its critical micelle concentration (CMC). The inhibition occurs through adsorption of the surfactant on the metal surface without modifying the mechanism of the corrosion process, which tested by UV-spectroscopy. The potential of zero charge (PZC) of aluminum and Al-7.0% Cu was studied by ac-impedance, and the mechanism of adsorption is discussed. The adsorption isotherm is described by Temkin adsorption isotherm. Thermodynamic functions for activation and adsorption process were determined.

  10. Temperature effect on gas phase alkylbenzene dealkylation

    International Nuclear Information System (INIS)

    Dealkylation of ethylbenzene, propylbenzene, and isopropylbenzene by radiolytically formed 2H3+ ions has been studied in the gaseous phase as a function of the irradiation temperature. The extent of the reaction, which increases with the temperature follows the order ethylbenzene -1 between the activation energies for dealkylation of ethylbenzene and isopropylbenzene, and of ethylbenzene and propylbenzene, respectively. (author)

  11. Las balanzas fiscales de las Comunidades Autónomas

    Directory of Open Access Journals (Sweden)

    Ezequiel Uriel

    2006-06-01

    Full Text Available En este artículo se examina la elaboración de las balanzas fiscales de las Comunidades Autónomas con respecto a la Administración Pública Central. Después de analizar los problemas metodológicos, se examinan los resultados obtenidos por el autor y se comparan con los obtenidos con simulaciones basadas en criterios normativos. Finalmente, en las conclusiones se hace una especial referencia a la interpretación de los saldos de balanzas fiscales obtenidos con los enfoques carga-beneficio (utilizado por el autor y flujo-monetario. En opinión del autor no son comparables los resultados con los dos enfoques. Además, el enfoque de flujo monetario no tiene una interpretación clara, a diferencia del enfoque carga beneficio que sí la tiene.

  12. Lernen von las Cuencas / Aprendiendo de las Cuencas

    DEFF Research Database (Denmark)

    Allen, Nacho Ruiz; López Arraiza, Sara

    2015-01-01

    Lernen von las Cuencas / Aprendiendo de las Cuencas (Learning from las Cuencas) research project, awarded with the EU Prize for Cultural Heritage / Europa Nostra Awards 2015, provides a new perspective of industrial cultural landscapes. Despite being focused on a local environment, the coal mining...... area of the Cuencas Mineras Centrales of Asturias, among its interests is to create a universal architectural story. The mining areas, after undergoing an intense process of industrialisation, have changed considerably over a brief period of time. In just a few decades, what were once natural valleys......-existence of natural, rural, industrial and urban landscapes came about in a totally uncontrolled and unplanned fashion. The fuzzy limits between the different landscapes foreclose the possibility of identifying their areas of influence. The Cuencas are perceived as a mesh of opposing yet interconnected identities...

  13. De las ecuaciones en diferencias finitas a las ecuaciones sumatorias

    OpenAIRE

    Poveda Ramos, Gabriel

    2012-01-01

    Las ecuaciones en diferencias finitas coristltuyen un material relativamente poco conocido, a  pesar de que desde el siglo pasado George Boole escribir una obra ya clásica sobre ellas, especialmente sobre las del tipo ordinario, con una sola variable discreta independiente. Sin embargo, el caso de dichas ecuaciones ordinarias lineales, es bien conocido de los tratadistas [1,2,3,5,6] y sobre él se conocen los teoremas de existencia y unicidad de soluciones, de superposición de soluciones pa...

  14. Las unidades entonacionales del habla de las mujeres de Valdivia

    OpenAIRE

    Gladys Cepeda

    1997-01-01

    Sobre la base del análisis de un corpus de 7.827 unidades entonacionales extractadas de una muestra representativa del habla de Valdivia en situación de entrevista, este trabajo presenta un inventario de las unidades entonacionales de uso más frecuente y de contraste estadísticamente significativo. El análisis identifica unidades secuenciales dentro de una misma unidad oracional y las asocia a su función modal (conclusividad, inconclusividad, solicitud de información, expresión de sentimiento...

  15. Las TIC, el proceso del conocimiento y las competencias docentes

    Directory of Open Access Journals (Sweden)

    Augusto Perez Lindo

    2014-11-01

    Full Text Available En el marco del Seminario Internacional "Formación y conocimiento" organizado por la Universidad de Sorocaba presentamos un análisis de los efectos de las TICs en los procesos del conocimiento. Tratamos de demostrar que esos efectos se producen en varias direcciones: cambios en la visión de la realidad, de la subjetividad, del lenguaje, de los paradigmas, de las relaciones sociales. Propone fortalecer competencias adecuadas al cambio de paradigma, como la capacidad para seleccionar e interpretar informaciones, la capacidad para pensar científicamente, la capacidad para comunicar, la capacidad para convivir, la capacidad para dominar varios lenguajes.

  16. Las pandillas juveniles centroamericanas y las respuestas de <>

    OpenAIRE

    Thale, Geoff

    2006-01-01

    Los gobiernos centroamericanos han respondido a los graves problemas de violencia juvenil y de pandillas con políticas policiales de «Mano Dura» y con el despliegue de las fuerzas armadas. Aunque esta estrategia tiene respaldo popular, es ineficaz en reducir la violencia pandillera (las tasas de homicidios en la región se han incrementado en lugar de bajar). Además, tiene consecuencias alarmantes para los procesos incipientes de reforma policial en la región. El involucra...

  17. Las promesas del imaginario Internet: Las comunidades virtuales

    Directory of Open Access Journals (Sweden)

    Agnès Vayreda i Duran

    2004-05-01

    Full Text Available Este texto se propone encontrar una respuesta a la pregunta sobre la atracción que ejerce Internet indagando en las promesas que este dispositivo nos depara. Una de las promesas que goza de mayor popularidad es la posibilidad de crear comunidades virtuales. Esta se ha ido construyendo a lo largo de más de tres décadas de diseños técnicos, experiencias y proyectos comunitarios como las primeras y restringidas comunidades de informáticos Arpanet y Usenet, las populares BBs y, más recientemente, la diversidad de proyectos comunitarios más o menos exitosos que pueblan Internet. En primer lugar, he realizado un pequeño recorrido histórico por algunos de los discursos de los primeros diseñadores/as y usuario/as con el fin de mostrar el contexto de gestación de esta promesa. En segundo lugar, he intentado conectar sus expectativas con el texto emblemático de Rheingold sobre CV que recoge experiencias más populares de CV de los años 80 y en EEUU. Mi objetivo es identificar, a modo de ejemplo (no se trata de un estudio exhaustivo, algunos de los contenidos de esta promesa que, a mi modo de ver, atraviesan con más o menos ímpetu, los proyectos actuales de comunidades virtuales.

  18. En las ciudades invisibles IX

    OpenAIRE

    Albertí, Miquel

    2009-01-01

    Cuzco, Ámsterdam: ciudades reales, visibles y circulares como Bram, en Francia, y la Connaught Place de Nueva Delhi, en India. La retícula de calles rectilíneas, ortogonal o no, es a la vez huella y símbolo de la forma urbana. En ocasiones inspira nombres numéricos para sus calles. En Nueva York, desde el sur de Manhattan hasta el Bronx, las calles paralelas al eje E-O se ordenan y nombran según los números naturales (de la 1st a la 242th street). De igual modo, las avenidas perpendiculares q...

  19. La violencia contra las mujeres

    OpenAIRE

    Gil Gómez, Alicia; Escrig Gil, Gemma; Forcada Martínez, Águeda

    2010-01-01

    Las mujeres con diversidad funcional en la agenda jurídico política española: la Ley estatal contra la violencia de género y sus nuevos desafíos,SOLEDAD ARNAU RIPOLLÉS. La violencia contra las mujeres. El estado de la cuestión: Una cuestión de estado. “La violencia en el ámbito laboral”, ENCARNA BARRAGÁN BRITO. El problema de la rehabilitación de los maltratadores, ESPERANZA BOSCH FIOL. La violencia política, LEONORA CASTAÑO CANO. La violencia psicológica, ...

  20. Seguridad de las plantas transgenicas

    OpenAIRE

    García Olmedo, Francisco

    2002-01-01

    Se trata de expone alguna idea relativas a la seguridad de las planta transgénicas, tema que he tratado extensamente en publicaciones anteriores 1 " 4 . Hablar de los riesgos de las plantas transgénicas y de los alimentos derivados de ellas - como de los de cualquier otra tecnología, sea la eléctrica o la del acero - no cabe hacerlo más que aplicación por aplicación. De hecho, la aprobación del cultivo y consumo de plantas transgénicas se hace caso por caso, según un ri...

  1. 聚醚砜酮的磺化及其在异丁烯低聚反应中的应用%Sulfonation of Poly(phthalazinone ether sulfone ketone) and Its Application to Isobutene Oligomerization

    Institute of Scientific and Technical Information of China (English)

    安增建; 周硼; 蹇锡高; 蔡天锡

    2003-01-01

    @@ Concentrated homogeneous mineral acids have been widely used as catalysts in industrial processes for several decades. These catalysts are corrosive to the apparatus, and there are large volumes of chemically reactive waste stream that are difficult to deal with[1]. In order to solve these problems, investigators have replaced these mineral acids with solid acid catalysts. Besides inorganic solid acid catalysts such as zeolite, solid organic polymeric resins containing acid groups, especially sulfuric acid resins such as Amberlyst[2], have attracted much attention. Compared with most inorganic acid catalysts, they have the advantages of their potentially high acidity, controllable surface area and porosity[3]. This article reports a novel sulfonated poly(phthalazinone ether sulfone ketone) (S-PPESK) resin and its application to isobutene oligomerization. S-PPESK exhibits high catalytic activity and excellent dimerization selectivity.

  2. Covalently bonded sulfonic acid magnetic graphene oxide: Fe3O4@GO-Pr-SO3H as a powerful hybrid catalyst for synthesis of indazolophthalazinetriones.

    Science.gov (United States)

    Doustkhah, Esmail; Rostamnia, Sadegh

    2016-09-15

    Multistep synthesis of covalently sulfonated magnetic graphene oxide was achieved by starting from Hummer's method to produce graphene oxide (GO) from chemical oxidation of graphite. Then, GO nanosheets were applied to support Fe3O4 nanoparticles (Fe3O4@GO) using co-precipitation method in the presence of GO sheets. This strategy led to formation of uniform particles of Fe3O4 on the surface of GO sheets. Then, it was sulfonated (Fe3O4@GO-Pr-SO3H) through modification with 3-mercaptopropyltrimethoxysilane (MPTMS) and subsequent oxidation with hydrogen peroxide (H2O2). In comparison, the covalently bonded propyl sulfonic acid groups were more prevailing rather to sulfonic acids of GO itself. The proposed catalyst was more active and recyclable at least for 11 runs. PMID:27309948

  3. Usos de las herramientas digitales entre las personas mayores

    Directory of Open Access Journals (Sweden)

    Javier Fombona Cadavieco

    2012-10-01

    Full Text Available Una sociedad «multiedades» supone diseñar y crear nuevos espacios de aprendizaje y comunicación, capaces de gestionar la demanda existente por parte de las personas mayores. En este artículo, se aborda la relación de las personas mayores con las tecnologías de la información y la comunicación (TIC y para ello se plantean dos objetivos: el primero va dirigido a conocer los recursos tecnológicos que utilizan y el segundo, a describir objetivamente los tipos de uso que estas personas hacen de las TIC. Para ello, se utiliza la técnica de encuesta, cuyos resultados son contrastados mediante grupos de discusión. En el estudio participaron 215 personas mayores usuarias de las TIC y siete grupos de discusión de cinco personas cada uno. Los resultados encontrados indican que los recursos que más utilizan los mayores son, los ordenadores e Internet y el uso que hacen de los mismos se ha agrupado en cuatro grandes categorías: formación, información, comunicación y entretenimiento, no encontrándose diferencias significativas en función del género o de la edad y sí se encontraron diferencias en cuanto a la disponibilidad de dichos recursos para uso particular en función del nivel de estudios.

  4. Las rondas de las mujeres por las ventanillas del Estado: Etnografia de un trabajo invisible

    Directory of Open Access Journals (Sweden)

    Emilia Schijman

    2011-06-01

    Full Text Available A partir de una investigación de campo en un barrio de vivienda social de la periferia parisina, el artículo explora los circuitos diarios de las mujeres por las oficinas del Estado. El análisis muestra el trabajo en la ventanilla como una movilización cotidiana, individual y colectiva, que liga sin cesar la esfera doméstica y la esfera pública, la práctica burocrática y la micro-política. Familiarizarse con las categorías administrativas y jurídicas, manipular diferentes regímenes de solicitación, juntar testigos y acumular pruebas escritas, todas estas actividades forman un trabajo invisible pero imprescindible para reclamar derechos y activar la economía de la familia.

  5. Sulfonate groups grafted on Ti6Al4V favor MC3T3-E1 cell performance in serum free medium conditions.

    Science.gov (United States)

    Felgueiras, Helena; Migonney, Véronique

    2014-06-01

    Ten years ago, we synthesized "bioactive model polymers" bearing sulfonate groups and proposed a mechanism of their modulation effect at different steps of the cell response. Then, we set up the grafting of polymers bearing sulfonate on Ti6Al4V surfaces by a grafting "from" technique making sure of the creation of covalent bonds between the grafted polymer and the Ti6Al4V surface. We have checked and confirmed the positive effect of grafted sulfonate groups on the osteoblastic cell response in vivo and in vitro but we did not elucidate the mechanism. The aim of this basic work consists first in investigating the role of sulfonate groups in the presence and in the absence of proteins at early stages of the osteointegration process on poly(sodium styrene sulfonate) poly(NaSS) grafted and ungrafted Ti6Al4V surfaces, in vitro. To understand the role of poly(NaSS) grafted chains on osteoblast-like cell response and to confirm/elucidate the importance of fetal bovine serum (FBS) proteins in the culture medium, MC3T3-E1 cells were seeded onto poly(NaSS) grafted and non-grafted Ti6Al4V surfaces. Cultures were carried out in a complete (10% FBS) and in a non-complete medium (without FBS). Cell viability assay, cell attachment number and cell adhesion strength were followed up to 3days of culture. The presence of proteins enhanced cell growth and development whatever the surface and the presence of sulfonate groups enhanced the cell attachment even in the absence of proteins, which suggests and confirms that the sulfonate groups can modify the activity of cells such as the secretion of binding proteins. Statistical differences were found in the attachment strength tests on poly(NaSS) grafted and ungrafted surfaces and showed that the sulfonate groups play an important role in the cell resistance to shear stress. PMID:24863216

  6. 共聚物 PDA 的磺化工艺研究%The Study of Sulfonation Process of Copolymers PDA

    Institute of Scientific and Technical Information of China (English)

    韩磊; 谢燕; 尚伟

    2014-01-01

    在水溶液聚合的条件下,利用磺甲基化原理,对共聚物PDA进行磺化改性,全面探讨影响磺化后产物相对分子质量的因素,对比分析磺化前后产品红外谱图。实验表明,磺化改性的较佳条件为:磺化温度为60℃、 n ( AM )砄n ( HCHO )砄n(Na2SO3)=1砄0.5砄1、磺化时间为4 h、磺化反应pH为8,合成SPDA分子量为4.39×105。%Under the conditions with solution polymerization , with the principal of sulfomethylation , PDA was modified by sulfonated.The factor influenced the relative molecular mass of sulfonated product was comprehensively studied , comparing the IR of product that sulfonated with the IR of product that after sulfonated.The result showed the sulfonated modified for better conditions were that sulfonation temperature was 60℃, n(AM):n(HCHO):n(Na2SO3)=1:0.5:1, sulfonated time was 4 h, sulfonation reaction pH was 8, and the relative molecular mass of SPDA was 4.39 ×105.

  7. A STUDY ON THE DEGRADATION MECHANISM OF PHOTOCROSSLINKING PRODUCTS FORMED BY CYCLIZED POLYISOPRENE-DIAZIDE SYSTEM UNDER THE INFLUENCE OF ALKYL BENZENE SULFONIC ACIDS

    Institute of Scientific and Technical Information of China (English)

    HUANG Junlian; SUN Meng

    1989-01-01

    The degradation mechanism of photocrosslinking products formed by cyclized polyisoprene-diazide system under the influence of the different alkyl benzene sulfonic acids was studied. The effects ofalkyl chain length and the concentration of alkyl benzene sulfonic acids on the rate of degradation reaction were discussed. It was found that in the initial stage of degradation, the cyclicity ratio and the average fused ring number did not change considerably, but the percentage of uncyclized parts content varied significantly. The suitable mechanism was supposed.

  8. Implicaciones del uso de las nuevas tecnologías en las relaciones sociales en las organizaciones productivas

    OpenAIRE

    Aguilar Barrientos, Sara

    2009-01-01

    Para la Administración, el tema de las relaciones sociales ha sido de especial interés, al ser éstas las que determinan de alguna manera la forma como se llevan a cabo los procesos que hacen posible alcanzar los tan anhelados objetivos de productividad y eficiencia en las organizaciones productivas. El buen funcionamiento de los procesos está a cargo de las personas que laboran en las organizaciones productivas, y por tanto, las relaciones que ellos establezcan con quienes les rodean, indepen...

  9. Chemical mechanical polishing of hard disk substrate with {alpha}-alumina-g-polystyrene sulfonic acid composite abrasive

    Energy Technology Data Exchange (ETDEWEB)

    Lei Hong, E-mail: hong_lei2005@yahoo.com.c [Research Center of Nano-science and Nano-technology, Shanghai University, Shanghai 200444 (China); Bu Naijing; Chen Ruling; Hao Ping [Research Center of Nano-science and Nano-technology, Shanghai University, Shanghai 200444 (China); Neng Sima; Tu Xifu; Yuen Kwok [Shenzhen Kaifa Magnetic Recording Co., LTD, Shenzhen, 518035 (China)

    2010-05-03

    {alpha}-Alumina-g-polystyrene sulfonic acid ({alpha}-Al{sub 2}O{sub 3}-g-PSS) composite abrasive was prepared by surface activation, graft polymerization and sulfonation, successively. The composition, dispersibility and morphology of the product were characterized by Fourier transformed infrared spectroscopy, laser particle size analysis and scanning electron microscopy, respectively. The chemical mechanical polishing (CMP) performances of the composite abrasive on hard disk substrate with nickel-phosphorous plating were investigated. The microscopy images of the polished surfaces show that {alpha}-Al{sub 2}O{sub 3}-g-PSS composite abrasive results in improved CMP and post-CMP cleaning performances than pure {alpha}-alumina abrasive under the same testing conditions.

  10. Preparation and Characterization of Sulfonic Acid Functionalized Silica and Its Application for the Esterification of Ethanol and Maleic Acid

    Science.gov (United States)

    Sirsam, Rajkumar; Usmani, Ghayas

    2016-04-01

    The surface of commercially available silica gel, 60-200 mesh size, was modified with sulfonic acid through surface activation, grafting of 3-Mercaptopropyltrimethoxysilane, oxidation and acidification of 3-Mercaptopropylsilica. Sulfonic Acid Functionalization of Silica (SAFS) was confirmed by Fourier Transform Infra-red (FTIR) spectroscopy and thermal gravimetric analysis. Acid-base titration was used to estimate the cation exchange capacity of the SAFS. Catalytic activity of SAFS was judged for the esterification of ethanol with maleic acid. An effect of different process parameters viz. molar ratio, catalyst loading, speed of agitation and temperature were studied and optimized by Box Behnken Design (BBD) of Response Surface Methodology (RSM). Quadratic model developed by BBD-RSM reasonably satisfied an experimental and predicted values with correlation coefficient value R2 = 0.9504.

  11. THERMODYNAMIC STUDY ON ADSORPTION OF AROMATIC SULFONIC ACIDS ONTO MACROPOROUS WEAK BASE ANION EXCHANGER FROM AQUEOUS SOLUTIONS

    Institute of Scientific and Technical Information of China (English)

    Chao Long; Quan-xing Zhang; Ai-min Li; Jin-long Chen

    2004-01-01

    The adsorption equilibrium isotherms of three aromatic sulfonic acid compounds, 2-naphthalenesulfonic acid, ptoluenesulfonic acid and p-chlorobenzenesulfonic acid, from aqueous solutions by macroporous weak base anion exchanger within the temperature range of 293 K-313 K were obtained. Several isotherm equations were correlated with the equilibrium data, and the experimental data was found to fit the three-parameter Redlich-Peterson equation best within the entire range of concentrations. The study showed that the hydrophobicity of solute has distinct influence on adsorption capacity of the anion exchanger for the aromatic sulfonic acid. Moreover, estimations of the isosteric enthalpy, free energy,and entropy change of adsorption were also reported. The positive isosteric enthalpy and entropy change for adsorption indicate an endothermic and entropy driven process in the present study.

  12. Effect of time and temperature exposition in the crystallinity degree of sulfonated poly-(styrene acrylic acid) (PSAA-S)

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, G.W.; Becker, E.B.; Silva, L.; Naspolini, A.M.; Consenso, E.C.; Paula, M.M.S.; Fiori, M.A., E-mail: glau_bn@hotmail.co [University of Extreme South of Santa Catarina Criciuma, SC (Brazil). Dept. of Materials Engineering; Silveira, F.Z. [Federal University of Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. of Chemical Engineering

    2010-07-01

    Polymers with special properties have been increasingly applied in the development of technological devices. For example, polymeric materials with special electric properties, such as sulfonated poly-(styrene-acrylic acid) - PSAA-S, are of great interest for showing different conductivities depending on the environment where they are applied. The special properties of PSAA are obtained only after sulfonation step in acidic media. The present work aimed to evaluate the effect of time and temperature exposition in the crystallinity degree of PSAA-S, through a statistical experimental factorial planning. The samples of PSAA-S were submitted to FT-IR and DRX tests. The results showed that the temperature and the time of exposition are significant factors in the crystallinity degree of PSAA-S, considering that the crystal lattices created during the polymerization are damaged by the action of time and temperature at which the polymer is exposed. (author)

  13. Synthesis and properties of poly(aryl sulfone benzimidazole) and its copolymers for high temperature membrane electrolytes for fuel cells

    DEFF Research Database (Denmark)

    Yang, Jingshuai; Li, Qingfeng; Cleemann, Lars Nilausen;

    2012-01-01

    Poly(aryl sulfone benzimidazole) (SO2PBI) and its copolymers with poly[2,2′-p-(phenylene)-5,5′-bibenzimidazole] (pPBI), termed as Co-SO2PBI, were synthesized with varied feeding ratios of 4,4′-sulfonyldibenzoic acid (SDBA) to terephthalic acid (TPA). Incorporation of the stiff para-phenylene and ......Poly(aryl sulfone benzimidazole) (SO2PBI) and its copolymers with poly[2,2′-p-(phenylene)-5,5′-bibenzimidazole] (pPBI), termed as Co-SO2PBI, were synthesized with varied feeding ratios of 4,4′-sulfonyldibenzoic acid (SDBA) to terephthalic acid (TPA). Incorporation of the stiff para...

  14. Production of biodiesel from palm fatty acid distillate using sulfonated-glucose solid acid catalyst:Characterization and optimization

    Institute of Scientific and Technical Information of China (English)

    Ibrahim M Lokman; Umer Rashid; Yun Hin Taufiq-Yap

    2015-01-01

    A palm fatty acid distillate (PFAD) has been used for biodiesel production. An efficient sulfonated-glucose acid catalyst (SGAC) was prepared by sulfonation to catalyze the esterification reaction. The effect of three variables i.e. methanol-to-PFAD molar ratio, catalyst amount and reaction time, on the yield of PFAD esters was studied by the response surface methodology (RSM). The optimum reaction conditions were:12.2:1 methanol-to-PFAD molar ratio, 2.9%catalyst concentration and 134 min of time as predicted by the RSM. The reaction under the optimum conditions resulted in 94.5%of the free fatty acid (FFA) conversion with 92.4%of the FAME yield. The properties of the PFAD esters were determined according to biodiesel standards.

  15. Las microempresas venezolanas en los noventa

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo López C.

    2004-01-01

    Full Text Available Este trabajo explora el apoyo de las gobernaciones venezolanas a las microempresas durante los años noventa, desde los inicios de la reestructuración económica y la descentralización. Se encontró: 1 clara tendencia de subordinación de las micro a las empresas de mayor tamaño, 2 apoyo financiero, técnico y comercial a las microempresas, como parte de un Plan Nacional de Enfrentamiento a la Pobreza, 3 inserción de las gobernaciones en este Plan a través de la descentralización y de acciones paralelas (independientes del gobierno nacional para apoyar a las microempresas. Se concluye que, habiendo sido promovidas formalmente para solucionar la pobreza, las políticas descentralizadoras favorecieron el papel de las microempresas en la acumulación.

  16. Violencia intrafamiliar contra las mujeres

    Directory of Open Access Journals (Sweden)

    Omar Huertas Díaz

    2012-07-01

    Full Text Available El presente texto pretende abordar el tema de violencia en contra de las mujeres desde la perspectiva familiar, es decir la violencia intrafamiliar o también llamada doméstica, entendida y afirmada desde la Corte Constitucional, como aquella violencia que causa daño o maltrato físico, psíquico o sexual, trato cruel, intimidatorio o degradante, amenaza, agravio, ofensa o cualquier otra forma de agresión, producida entre miembros de una familia, llámese cónyuge o compañero permanente, padre o madre, aunque no convivan bajo el mismo techo, ascendientes o descendientes de estos incluyendo hijos adoptivos, y en general todas las personas que de manera permanente se hallaren integrados a la unidad doméstica. Junto a ello el documento explicará de qué forma afecta esta particular clase de violencia a las mujeres, los abusos y malos tratos que la materializan, y las medidas adoptadas por el Estado Colombiano para enfrentar sus consecuencias, y por último la presentación de los conceptos que maneja la Corte Constitucional en la interpretación de dicho fenómeno.

  17. Del aislacionismo a las alianzas

    Directory of Open Access Journals (Sweden)

    Michavila, Francisco

    2011-12-01

    Full Text Available The universities have passed to look within to seek opportunities for collaboration, either between universities or with public and private entities in other areas. The construction of the European Higher Education Area and the internationalization of universities have made cooperation and partnerships an emerging value for the future. In a scenario of competition between universities, partnerships are essential for the multiplication of opportunities in attracting top students, teachers and university researchers, and to improve the results of university activity.

    Las universidades han pasado de mirar al interior a la búsqueda de oportunidades para la colaboración, sea entre universidades o con entidades públicas y privadas de otros ámbitos. La construcción del Espacio Europeo de Educación Superior y la internacionalización de las universidades han convertido a la cooperación y las alianzas en un valor emergente para el futuro. En un escenario de competencia entre universidades, las alianzas son indispensables para la multiplicación de oportunidades en la captación de los mejores estudiantes, profesores e investigadores universitarios, así como para favorecer los resultados de la actividad universitarias.

  18. El camino a las estrellas

    OpenAIRE

    Duque Escobar, Gonzalo

    2006-01-01

    Cómo evolucionamos por la cultura. Cómo aparecen las civilizaciones. De la astronomía aristotélica a Galileo. Gravitación y Relatividad. Del Homo Hábilis al Homo Sapiens. De los griegos al Renacimiento. América precolombina. De Newton a Hawking.

  19. Los Problemas de las Gimnasias

    Directory of Open Access Journals (Sweden)

    Viviana Bulus Rossini

    2011-11-01

    Full Text Available Este artículo se propone sintetizar las principales ideas de las ponencias presentadas en la Mesa de Trabajo "Los problemas de las Gimnasias" que se desarrolló en el marco del 9º Congreso Argentino y 4º Latinoamericano de Educación Física y Ciencias realizado en la Universidad Nacional de La Plata en junio de 2011. Todas ellas coinciden en pensar a la Gimnasia como parte fundamental de una Educación Corporal que se proponga transmitir aquellos saberes corporales culturalmente significativos que sirvan de herramientas para el conocimiento, el cuidado y la autogestión del propio cuerpo. A partir de estos puntos de coincidencia cada ponencia se explaya en su especificidad: ya sea desde la investigación y el análisis de los textos de divulgación y académicos, de los discursos de profesores, alumnos y practicantes; desde el análisis crítico del campo gímnico actual; desde propuestas bien concretas de trabajo de las gimnasias, en este caso la gimnasia aeróbica, la gimnasia funcional, el Método Pilates, o la gimnasia en el Profesorado en Educación Física con proyección en la gimnasia escolar

  20. Review on Modification of Sulfonated Poly (-ether-ether-ketone Membranes Used as Proton Exchange Membranes

    Directory of Open Access Journals (Sweden)

    Xiaomin GAO

    2015-11-01

    Full Text Available The proton exchange membrane fuel cell (PEMFC is a type of modern power, but the traditional proton exchange membranes (PEM of PEMFC are limited by high methanol permeability and water uptake. Poly-ether-ether-ketone (PEEK is a widely used thermoplastic with good cost-effective property. Sulfonated poly (-ether-ether-ketone (SPEEK has high electric conductivity and low methanol permeability, as well as comprehensive property, which is expected to be used as PEMs. However, the proton exchange ability, methanol resistance, mechanical property and thermal stability of SPEEK are closely related to the degree of sulfonation (DS of SPEEK membranes. Additionally, the proton conductivity, methanol permeability, and stability of SPEEK membranes applied in various conditions need to be further improved. In this paper, the research into modification of SPEEK membranes made by SPEEK and other polymers, inorganic materials are introduced. The properties and modification situation of the SPEEK and the composite membranes, as well as the advantages and disadvantages of membranes prepared by different materials are summarized. From the results we know that, the methanol permeability of SPEEK/PES-C membranes is within the order of magnitude, 10-7cm2/s. The proton conductivity of the SPPESK/SPEEK blend membrane reaches 0.212 S cm-1 at 80 °C. The cross-linked SPEEK membranes have raised thermal and dimensional stability. The non-solvent caused aggregation of the SPEEK ionomers. The proton conductivity of SPEEK/50%BMIMPF6/4.6PA membrane maintains stable as 2.0 x 10-2S cm-1 after 600 h at 160 °C. Incorporation of aligned CNT into SPEEK increases the proton conductivity and reduces the methanol permeability of the composite membranes. The PANI improves the hydrothermal stability. More proton transfer sites lead to a more compact structure in the composite membranes. According to the results, the proton exchange capacity, water uptake, and conductivity of

  1. Crystal structure of tetra-methyl-tetra-thia-fulvalenium (1S)-camphor-10-sulfonate dihydrate.

    Science.gov (United States)

    Sommer, Mathieu; Allain, Magali; Mézière, Cécile; Pop, Flavia; Giffard, Michel

    2015-07-01

    Electro-oxidation of tetra-methyl-tetra-thia-fulvalene (TMTTF) in the presence of the chiral anion (1S)-camphor-10-sulfonate (S-camphSO3 (-)) in tetra-hydro-furan/water medium afforded a 1/1 salt formulated as TMTTF·S-camphSO3·2H2O or 2-(4,5-dimethyl-1,3-di-thiol-2-yl-idene)-4,5-dimethyl-1,3-di-thiole radical ion (1+) [(1S)-7,7-dimethyl-2-oxobi-cyclo-[2.2.1]heptan-1-yl]methane-sulfonate dihydrate, C10H12S4 (+)·C10H15O4S(-)·2H2O. In this salt, two independent TMTTF units are present but, in both cases, the observed bond lengths and especially the central C=C distance [1.392 (6) and 1.378 (6) Å] are in agreement with a complete oxidation of TMTTF which is thus present as TMTTF (.) (+) radical cations. These cations form one-dimensional stacks in which they are associated two by two, forming dimers with short [3.472 (1) to 3.554 (2) Å] S⋯S contacts. The two S-camphSO3 anions present also form stacks and are connected with each other via the water mol-ecules with many O-H⋯O hydrogen bonds ranging from 1.86 (3) to 2.15 (4) Å; the O-H⋯O hydrogen-bonding network can be described as being constituted of C 2 (2)(6) chains bearing R 3 (3)(11) lateral rings. On the other hand, the columns of cations and anions are connected through C-H⋯O hydrogen bonds, forming a system expanding in three directions; finally, the result is a three-dimensional network of O-H⋯O and C-H⋯O hydrogen bonds. PMID:26279858

  2. Toward 5 V Li-Ion Batteries: Quantum Chemical Calculation and Electrochemical Characterization of Sulfone-Based High-Voltage Electrolytes.

    Science.gov (United States)

    Wu, Feng; Zhou, Hang; Bai, Ying; Wang, Huali; Wu, Chuan

    2015-07-15

    In seeking new sulfone-based electrolytes to meet the demand of 5 V lithium-ion batteries, we have combined the theoretical quantum chemistry calculation and electrochemical characterization to explore several sulfone/cosolvent systems. Tetramethylene sulfone (TMS), dimethyl sulfite (DMS), and diethyl sulfite (DES) were used as solvents, and three kinds of lithium salts including LiBOB, LiTFSI, and LiPF6 were added into TMS/DMS [1:1, (v)] and TMS/DES [1:1, (v)] to form high-voltage electrolyte composites, respectively. All of these electrolytes display wide electrochemical windows of more than 5.4 V, with the high electrolyte conductivities being more than 3 mS/cm at room temperature. It is indicated that to achieve the best ionic conductivity in TMS/DMS cosolvent, the optimized concentrations of lithium salts LiBOB, LiTFSI, and LiPF6 were 0.8, 1, and 1 M, respectively. Furthermore, the vibrational changes of the molecular functional groups in the cosolvents were evaluated by Fourier transform infrared spectroscopy. It is found that lithium salts show strong interaction with the main functional sulfone groups and sulfonic acid ester group, thus playing a vital role in the enhancement of the ionic conductivity and electrochemical stability of the solvent system. These sulfone-based solvents with high electrochemical stability are expected to become a new generation of a high-voltage organic electrolytic liquid system for lithium-ion batteries. PMID:26087246

  3. Clinical Efficacy of Andrographolide Sulfonate in the Treatment of Severe Hand, Foot, and Mouth Disease (HFMD) is Dependent upon Inhibition of Neutrophil Activation.

    Science.gov (United States)

    Wen, Tao; Xu, Wenjun; Liang, Lianchun; Li, Junhong; Ding, Xiaorong; Chen, Xiao; Hu, Jianhua; Lv, Aiping; Li, Xiuhui

    2015-08-01

    Andrographolide sulfonate treatment has been shown to improve clinical severe hand, foot, and mouth disease (HFMD) efficacies when combined with conventional therapy. However, the mechanisms for its therapeutic effects remain elusive. In this study, we aimed to investigate whether andrographolide sulfonate exerts its efficacy by acting on neutrophil activation. We obtained serial plasma samples at two time points (before and after 5 days of therapy) from 28 HFMD patients who received conventional therapy and 18 patients who received combination therapy (andrographolide sulfonate plus conventional therapy). Then, we measured plasma myeloperoxidase (MPO), S100A8/A9, histone, and inflammatory cytokine levels. Furthermore, we examined if andrographolide sulfonate had direct effects on neutrophil activation in vitro. We observed that MPO and S100A8/A9 levels were markedly elevated in the HFMD patients before clinical treatment. At 5 days post-medication, the MPO, S100A8/A9, histone, and interleukin-6 levels were markedly lower in the combination therapy group compared with the conventional therapy group. In vitro studies showed that andrographolide sulfonate inhibited lipopolysaccharide-stimulated neutrophil activation, demonstrated by the decreased production of reactive oxygen species and cytokines. These data indicate that neutrophil activation modulation by andrographolide sulfonate may be a critical determinant for its clinical HFMD treatment efficacy. Copyright © 2015 John Wiley & Sons, Ltd. PMID:25960284

  4. New pathway for degradation of sulfonated azo dyes by microbial peroxidases of Phanerochaete chrysosporium and Streptomyces chromofuscus.

    OpenAIRE

    Goszczynski, S; Paszczynski, A; Pasti-Grigsby, M B; Crawford, R L; Crawford, D. L.

    1994-01-01

    Pathways for the degradation of 3,5-dimethyl-4-hydroxy-azobenzene-4'-sulfonic acid (I) and 3-methoxy-4-hydroxyazobenzene-4'-sulfonamide (II) by the manganese peroxidase and ligninase of Phanerochaete chrysosporium and by the peroxidase of Streptomyces chromofuscus have been proposed. Twelve metabolic products were found, and their mechanisms of formation were explained. Preliminary oxidative activation of the dyes resulted in the formation of cationic species, making the molecules vulnerable ...

  5. Ag nanoparticle/melamine sulfonic acid supported on silica gel as an efficient catalytic system for synthesis of dihydropyrimidinthiones

    Directory of Open Access Journals (Sweden)

    Parya Nasehi

    2014-07-01

    Full Text Available 3,4-Dihydropyrimidin-2(1H-thiones were synthesized in the presence of Ag nanoparticle/melamine sulfonic acid (MSA supported on silica gel. The reactionwas carried out at 110 oC for 20 min under solvent free conditions. This method hassome advantages such as good yield, mild reaction conditions, ease of operation and work up, short reaction time and high product purity.

  6. Adsorption of Sodium Dodecylbenzene Sulfonate on Highly Humic Non-allophanic Andisol at High-Electrolyte Concentration

    OpenAIRE

    Ahmed, Farook; ISHIGURO, Munehide; MORIGUCHI, Kazuki

    2012-01-01

    To clarify the adsorption characteristics of surfactants, it is important to understand the surfactant behavior in the soil and water environments.However,there are few adsorption studies for highly humic soil. In this study, the adsorption characteristics of dodecylbenzene sulfonates in a highly humic soil were investigated. A non‒allophanic Andisol was used since this soil contains a large amount of humic substances and is only negatively charged. Thus, electrically, only repulsive force is...

  7. Cyclic Oligomers of Phenolphthalein Polyarylene Ether Sulfone (Ketone):Preparation Through Cyclo-depolymerisation of Corresponding Polymers

    Institute of Scientific and Technical Information of China (English)

    Hong Hua WANG; Jin Ying DING; Tian Lu CHEN

    2004-01-01

    Cyclic oligomers of phenolphthalein polyarylene ether sulfone(ketone) were prepared through cyclo-depolymerisation of corresponding polymers using CsF as the catalyst in dipolar aprotic solvent DMAc and DMF, and a family of macrocycles containing from dimer up to at least heptamer were confirmed by GPC, HPLC and MALDI-TOF-MS. The yields of cyclics get as high as 86.3% and 87.9% respectively.

  8. Successful treatment of a colonic ulcer penetrating the urinary bladder caused by the administration of calcium polystyrene sulfonate and sorbitol.

    Science.gov (United States)

    Shioya, Takeshi; Yoshino, Masanori; Ogata, Masao; Shibuya, Tetsuo; Tokunaga, Akira; Matsumoto, Koshi; Tajiri, Takashi

    2007-10-01

    A 77-year-old woman was urgently admitted for the treatment of diabetic ketoacidosis and a duodenal ulcer hemorrhage in March 1999. She had a history of diabetes and angina pectoris. After admission, she received oral calcium polystyrene sulfonate and sorbitol to treat hyperkalemia. Nine days later, severe abdominal pain developed. A colonoscopic examination revealed a sigmoid colonic ulcer and stenosis; the patient was treated conservatively. At a 1-year follow-up examination, the colonic stenosis was found have worsened; pneumaturia developed in January 2001. The patient was found to have a sigmoidovesical fistula and underwent sigmoidectomy and partial resection of the ileum and urinary bladder. The histological findings were a benign colonic ulcer with the infiltration of inflammatory cells, mainly lymphocytes. Rhomboidal, dark violet Kayexalate crystals were observed on microscope examination in the submucosa in both the first and second colonic biopsy specimens. We concluded that the colonic ulcer and the sigmoidovesical fistula had been caused by the administration of calcium polystyrene sulfonate and sorbitol. Reports of colonic perforation as a result of the administration of calcium polystyrene sulfonate and sorbitol are rare. Here, we report the successful treatment of a colonic ulcer that had penetrated the urinary bladder.

  9. Organic-inorganic hybrid proton exchange membrane based on polyhedral oligomeric silsesquioxanes and sulfonated polyimides containing benzimidazole

    Science.gov (United States)

    Pan, Haiyan; Zhang, Yuanyuan; Pu, Hongting; Chang, Zhihong

    2014-10-01

    A new series of organic-inorganic hybrid proton exchange membranes (PEMs) were prepared using sulfonated polyimides containing benzimidazole (SPIBIs) and glycidyl ether of polyhedral oligomeric silsesquioxanes (G-POSS). SPIBIs were synthesized using 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA), 5-amino-2-(4-aminophenyl) benzimidazole (APBIA) and 4,4‧-diaminodiphenyl ether-2,2‧-disulfonic acid (ODADS). The organic-inorganic cross-linked membranes can be prepared by SPIBIs with G-POSS by a thermal treatment process. The cross-linking density of the membranes was evaluated by gel fractions. The water uptake, swelling ratio, mechanical property, thermal behavior, proton conductivity, oxidative and hydrolytic stability of the cross-linked organic-inorganic membranes were intensively investigated. All the cross-linked membranes exhibit high cross-linking density for the gel fraction higher than 70%. Compared to pristine membranes (SPIBIs) and membranes without benzimidazole groups (SPI), the anti-free-radical oxidative and hydrolytic stabilities of cross-linked membranes are significantly higher. The anti-free-oxidative stability of SPIBI-100-P (cross-linked SPIBI membrane with 100% degree of sulfonation) is nearly four-fold higher than that of SPIBI-100. The proton conductivity of the cross-linked membranes ranges from 10-3 S cm-1 to 10-2 S cm-1 depending both on the degree of sulfonation (DS) of the SPIBI and temperature.

  10. Functionalized carbon nanotube-poly(arylene sulfone) composite membranes for direct methanol fuel cells with enhanced performance

    Science.gov (United States)

    Joo, Sang Hoon; Pak, Chanho; Kim, Eun Ah; Lee, Yoon Hoi; Chang, Hyuk; Seung, Doyoung; Choi, Yeong Suk; Park, Jong-Bong; Kim, Tae Kyoung

    A new type of composite membrane, consisting of functionalized carbon nanotubes (CNTs) and sulfonated poly(arylene sulfone) (sPAS), is prepared for direct methanol fuel cell (DMFC) applications. The CNTs modified with sulfonic acid or PtRu nanopaticles are dispersed within the sPAS matrix by a solution casting method to afford SO 3CNT-sPAS or PtRu/CNT-sPAS composite membranes, respectively. Characterization of the composite membranes reveals that the functionalized CNTs are homogeneously distributed within the sPAS matrix and the composite membranes contain smaller ion clusters than the neat sPAS. The composite membranes exhibit enhanced mechanical properties in terms of tensile strength, strain and toughness, which leads to improvements in ion conductivity and methanol permeability compared with the neat sPAS membrane. In DMFC performance tests, the use of a PtRu/CNT-sPAS membrane yields high power density compared with the neat sPAS membrane, which demonstrates that the improved properties of the composite membranes induce an increase in power density. The strategy for CNT-sPAS composite membranes presented in this work can potentially be extended to other CNT-polymer composite systems.

  11. Modulation of Phosphopeptide Fragmentation via Dual Spray Ion/Ion Reactions Using a Sulfonate-Incorporating Reagent.

    Science.gov (United States)

    Cotham, Victoria C; McGee, William M; Brodbelt, Jennifer S

    2016-08-16

    The labile nature of phosphoryl groups has presented a long-standing challenge for the characterization of protein phosphorylation via conventional mass spectrometry-based bottom-up proteomics methods. Collision-induced dissociation (CID) causes preferential cleavage of the phospho-ester bond of peptides, particularly under conditions of low proton mobility, and results in the suppression of sequence-informative fragmentation that often prohibits phosphosite determination. In the present study, the fragmentation patterns of phosphopeptides are improved through ion/ion-mediated peptide derivatization with 4-formyl-1,3-benezenedisulfonic acid (FBDSA) anions using a dual spray reactor. This approach exploits the strong electrostatic interactions between the sulfonate moieties of FBDSA and basic sites to facilitate gas-phase bioconjugation and to reduce charge sequestration and increase the yield of phosphate-retaining sequence ions upon CID. Moreover, comparative CID fragmentation analysis between unmodified phosphopeptides and those modified online with FBDSA or in solution via carbamylation and 4-sulfophenyl isothiocyanate (SPITC) provided evidence for sulfonate interference with charge-directed mechanisms that result in preferential phosphate elimination. Our results indicate the prominence of charge-directed neighboring group participation reactions involved in phosphate neutral loss, and the implementation of ion/ion reactions in a dual spray reactor setup provides a means to disrupt the interactions by competing hydrogen-bonding interactions between sulfonate groups and the side chains of basic residues. PMID:27467576

  12. Enhancement of proton conductivity of chitosan membrane enabled by sulfonated graphene oxide under both hydrated and anhydrous conditions

    Science.gov (United States)

    Liu, Yahua; Wang, Jingtao; Zhang, Haoqin; Ma, Chuanming; Liu, Jindun; Cao, Shaokui; Zhang, Xiang

    2014-12-01

    In this study, sulfonated graphene oxide (SGO) nanosheets with controllable sulfonic acid group loading are synthesized via the facile distillation-precipitation polymerization, and then incorporated into chitosan (CS) matrix to prepare nanohybrid membranes. The microstructure and physicochemical properties of the resulting membranes are extensively investigated. Compared with CS control and GO-filled membranes, SGO-filled membranes attain enhanced thermal and mechanical stabilities due to the strong electrostatic attractions between -SO3H of SGO and -NH2 of CS, which inhibit the mobility of CS chains. Additionally, the inhibited mobility reduces the area swellings of SGO-filled membranes, reinforcing their structural stabilities. The incorporation of SGO generates acid-base pairs along CS-SGO interface, which work as facile proton-hoping sites and thus construct continuous and wide proton transfer pathways, yielding enhanced proton conductivities under both hydrated and anhydrous conditions. Meanwhile, the conductivity can be elevated by increasing the sulfonic acid group loading and content of SGO. Particularly, incorporating 2.0% S4GO can afford the nanohybrid membrane a 122.5% increase in hydrated conductivity and a 90.7% increase in anhydrous conductivity when compared with CS control membrane. The superior conduction properties then offered a significant enhancement in H2/O2 cell performances to the nanohybrid membranes, guaranteeing them to be promising proton exchange membranes.

  13. Synthesis and Characterization of Sulfonated Poly(Phenylene Containing a Non-Planar Structure and Dibenzoyl Groups

    Directory of Open Access Journals (Sweden)

    Hohyoun Jang

    2016-02-01

    Full Text Available Polymers for application as sulfonated polyphenylene membranes were prepared by nickel-catalyzed carbon-carbon coupling reaction of bis(4-chlorophenyl-1,2-diphenylethylene (BCD and 1,4-dichloro-2,5-dibenzoylbenzene (DCBP. Conjugated cis/trans isomer (BCD had a non-planar conformation containing four peripheral aromatic rings that facilitate the formation of π–π interactions. 1,4-Dichloro-2,5-dibenzoylbenzene was synthesized from the oxidation reaction of 2,5-dichloro-p-xylene, followed by Friedel-Crafts reaction with benzene. DCBP monomer had good reactivity in polymerization affecting the activity of benzophenone as an electron-withdrawing group. The polyphenylene was sulfonated using concentrated sulfuric acid. These polymers without any ether linkages on the polymer backbone were protected from nucleophilic attack by hydrogen peroxide, hydroxide anion, and radicals generated by polymer electrolyte membrane fuel cell (PEMFC operation systems. The mole fraction of the sulfonic acid groups was controlled by varying the mole ratio of bis(4-chlorophenyl-1,2-diphenylethylene in the copolymer. In comparison with Nafion 211® membrane, these SBCDCBP membranes showed ion exchange capacity (IEC ranging from 1.04 to 2.07 meq./g, water uptake from 36.5% to 69.4%, proton conductivity from 58.7 to 101.9 mS/cm, and high thermal stability.

  14. Electrochemistry and electrocatalysis of myoglobin immobilized in sulfonated graphene oxide and Nafion films.

    Science.gov (United States)

    Chen, Guiying; Sun, Hong; Hou, Shifeng

    2016-06-01

    In this study, sulfonated graphene oxide (SGO) was synthesized and characterized by Fourier transform infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS). It was used to make Mb-SGO-Nafion composite films by coating myoglobin (Mb) on the glassy carbon electrodes (GCE). Positions of the Soret absorption bands suggested that Mb retained its native conformation in the films. Mb-SGO-Nafion film modified electrode showed a pair of well-defined and nearly reversible cyclic voltammetry peaks at around -0.39 V versus saturated calomel electrode (SCE) in pH 7.0 buffers, characteristic of heme Fe(III)/Fe(II) redox couples. Electrochemical parameters such as electron transfer rate constant (ks) and formal potential (E(o')) were estimated by fitting the data of square-wave voltammetry with nonlinear regression analysis. Experimental data demonstrated that the electron transfer between Mb and electrode was greatly facilitated and showed good electrocatalytic properties toward various substrates, such as H2O2 and NaNO2, with significant lowering of reduction overpotential. PMID:27019153

  15. Spontaneous modification of graphite anode by anthraquinone-2-sulfonic acid for microbial fuel cells.

    Science.gov (United States)

    Tang, Xinhua; Li, Haoran; Du, Zhuwei; Ng, How Yong

    2014-07-01

    In this study, anthraquinone-2-sulfonic acid (AQS), an electron transfer mediator, was immobilized onto graphite felt surface via spontaneous reduction of the in situ generated AQS diazonium cations. Cyclic voltammetry (CV) and energy dispersive spectrometry (EDS) characterizations of AQS modified graphite demonstrated that AQS was covalently grafted onto the graphite surface. The modified graphite, with a surface AQS concentration of 5.37 ± 1.15 × 10(-9)mol/cm(2), exhibited good electrochemical activity and high stability. The midpoint potential of the modified graphite was about -0.248 V (vs. normal hydrogen electrode, NHE), indicating that electrons could be easily transferred from NADH in bacteria to the electrode. AQS modified anode in MFCs increased the maximum power density from 967 ± 33 mW/m(2) to 1872 ± 42 mW/m(2). These results demonstrated that covalently modified AQS functioned as an electron transfer mediator to facilitate extracellular electron transfer from bacteria to electrode and significantly enhanced the power production in MFCs.

  16. Protein quantification by MALDI-selected reaction monitoring mass spectrometry using sulfonate derivatized peptides.

    Science.gov (United States)

    Lesur, Antoine; Varesio, Emmanuel; Hopfgartner, Gérard

    2010-06-15

    The feasibility of protein absolute quantification with matrix-assisted laser desorption/ionization (MALDI) using the selected reaction monitoring (SRM) acquisition mode on a triple quadrupole linear ion trap mass spectrometer (QqQ(LIT)) equipped with a high-frequency laser is demonstrated. A therapeutic human monoclonal antibody (mAb) was used as a model protein, and four tryptic peptides generated by fast tryptic digestion were selected as quantification surrogates. MALDI produces mostly singly charged peptides which hardly fragment under low-energy collision-induced dissociation (CID), and therefore the benefits of using 4-sulfophenyl isothiocyanate (SPITC) as a fragmentation enhancer derivatization agent were evaluated. Despite a moderate impact on the sensitivity, the N-terminus sulfonated peptides generate nearly complete y-ion ladders when native peptides produce few fragments. This aspect provides an alternative SRM transition set for each peptide. As a consequence, SRM transitions selectivity can be tuned more easily for peptide quantitation in complex matrices when monitoring several SRM transitions. From a quantitative point of view, the signal response depending on mAb concentration was found to be linear over 2.5 orders of magnitude for the most sensitive peptide, allowing precise and accurate measurement by MALDI-SRM/MS. PMID:20481516

  17. Sodium Tanshinone IIA Sulfonate Attenuates Scopolamine-Induced Cognitive Dysfunctions via Improving Cholinergic System.

    Science.gov (United States)

    Xu, Qing-Qing; Xu, Yi-Jun; Yang, Cong; Tang, Ying; Li, Lin; Cai, Hao-Bin; Hou, Bo-Nan; Chen, Hui-Fang; Wang, Qi; Shi, Xu-Guang; Zhang, Shi-Jie

    2016-01-01

    Sodium Tanshinone IIA sulfonate (STS) is a derivative of Tanshinone IIA (Tan IIA). Tan IIA has been reported to possess neuroprotective effects against Alzheimer's disease (AD). However, whether STS possesses effect on AD remains unclear. This study aims to estimate whether STS could protect against scopolamine- (SCOP-) induced learning and memory deficit in Kunming mice. Morris water maze results showed that oral administration of STS (10 mg/kg and 20 mg/kg) and Donepezil shortened escape latency, increased crossing times of the original position of the platform, and increased the time spent in the target quadrant. STS decreased the activity of acetylcholinesterase (AChE) and increased the activity of choline acetyltransferase (ChAT) in the hippocampus and cortex of SCOP-treated mice. Oxidative stress results showed that STS increased the activity of superoxide dismutase (SOD) and decreased the levels of malondialdehyde (MDA) and reactive oxygen species (ROS) in hippocampus and cortex. In addition, western blot was carried out to detect the expression of apoptosis related proteins (Bcl-2, Bax, and Caspase-3). STS upregulated the protein expression of Bcl-2 and downregulated the proteins expression of Bax and Caspase-3. These results indicated that STS might become a promising therapeutic candidate for attenuating AD-like pathological dysfunction. PMID:27556046

  18. Molecular deformation and stress-strain behavior of poly(bisphenol-A-diphenyl sulfone)

    Science.gov (United States)

    Hong, S.-D.; Chung, S. Y.; Fedors, R. F.

    1983-01-01

    The strain-birefringence response of poly(bisphenol-A-diphenyl sulfone) is found to be independent of temperature at temperatures below -100 C; at higher temperatures, the response becomes slightly dependent on temperature, with lower birefringence seen at higher temperatures. The stress-strain behavior and the stress-birefringence response both depend on temperature over the entire testing temperature range (-179 C to 150 C) studied; this dependence, however, is not pronounced. The evidence is seen as suggesting that the polymer molecules respond to deformation by undergoing conformational rearrangements; the mode of the molecular deformation remains unchanged for temperatures of -100 C or lower. At higher temperatures, the average length of the chain segments involved in the rearrangement increases. The stress-strain response is attributed mainly to chain orientation. The entropic contribution deriving from chain orientation at temperatures below -100 C is still substantial. The modest temperature dependence of the stress-strain response suggests that the energy barriers for the chain segments involved in the rearrangement are relatively low.

  19. Removal of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) from water by coagulation: mechanisms and influencing factors.

    Science.gov (United States)

    Bao, Yueping; Niu, Junfeng; Xu, Zesheng; Gao, Ding; Shi, Jianghong; Sun, Xiaomin; Huang, Qingguo

    2014-11-15

    In this study, alum (Al2(SO4)3⋅18H2O), ferric chloride (FeCl3⋅6H2O) and polyaluminium chloride (PACl) were used to remove perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) from water. The influencing factors, including pH and natural organic matter (NOM), were investigated. A positive correlation was found between the size of the flocs and the removal efficiency of PFOX (X=S and A). The removal ratios of PFOS and PFOA were 32% and ∼12%, respectively, when 50 mg/L of FeCl3⋅6H2O was added as the coagulant at the initial pH. Coagulation achieved high removal ratios for PFOX under acidic conditions (∼47.6% and 94.7% for PFOA and PFOS at pH 4, respectively). In addition, increasing NOM concentrations decreased the removal rates of PFOX because of the existence of competitive adsorption between NOM molecules and PFOX on the surface of the coagulants and flocs. The combination of adsorption by powdered activated carbon (PAC) and coagulation increased the removal ratios up to >90% for PFOX at the initial concentration of 1mg/L, implying that the adsorption enhanced coagulation. Meantime, the experiments with natural water showed that coagulation is a feasible method to remove PFOS and PFOA from surface water.

  20. Preparation of Chitosan/Polystyrene Sulfonate Multilayered Composite Metal Nanoparticles and Its Application.

    Science.gov (United States)

    Xiong, Fangxin; Chen, Chunxiao; Liu, Shantang

    2016-06-01

    Metal-Chitosan (CTS) composite was first synthesized through the metal composition of chitosan (CTS) and metal ions. The formed composite was alternately deposited on the base with sodium polystyrene sulfonate (PSS) through a layer-by-layer self-assembling technique, followed by an in situ reduction by sodium borohydride to produce a polyelectrolyte nanocomposite thin film containing metal nanoparticles. Assembly, surface morphology and electrochemical properties of the composite membrane were analyzed by UV-visible absorption spectroscopy (UV-vis), atomic force microscopy (AFM) and cyclic voltammetry (CV). The UV-Vis results indicated that the absorbance of the multilayer film at the characteristic absorption peak increased as the membrane bilayers increased, in a good linear relationship, which demonstrated that the multilayer film was uniformly assembled on the base. AFM images showed that the surface of the multilayer thin-film composite had some degree of roughness and metal nanoparticles of 10-20 nm in size were generated on the membrane. The CV results indicated that the metal nanocomposite film had excellent electrocatalytic activity to glucose and had a potential for applications in electrochemical sensors.