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Sample records for benzene sulfonic acid

  1. 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.

  2. Crystal structure of 2-benzene­sulfon­amido-3-hy­droxy­propanoic acid

    Science.gov (United States)

    Jabeen, Nabila; Mushtaq, Misbah; Danish, Muhammad; Tahir, Muhammad Nawaz; Raza, Muhammad Asam

    2015-01-01

    In the title compound, C9H11NO5S, the O=S=O plane of the sulfonyl group is twisted at a dihedral angle of 52.54 (16)° with respect to the benzene ring. The dihedral angle between the carb­oxy­lic acid group and the benzene ring is 49.91 (16)°. In the crystal, C—H⋯O, N—H⋯O and O—H⋯O hydrogen bonds link the mol­ecules into (001) sheets. PMID:26594589

  3. Electrochemical detection of Hg(II in water using self-assembled single walled carbon nanotube-poly(m-amino benzene sulfonic acid on gold electrode

    Directory of Open Access Journals (Sweden)

    Gauta Gold Matlou

    2016-09-01

    Full Text Available This work reports on the detection of mercury using single walled carbon nanotube-poly (m-amino benzene sulfonic acid (SWCNT-PABS modified gold electrode by self-assembled monolayers (SAMs technique. A thiol containing moiety (dimethyl amino ethane thiol (DMAET was used to facilitate the assembly of the SWCNT-PABS molecules onto the Au electrode surface. The successfully assembled monolayers were characterised using atomic force microscopy (AFM. Cyclic voltammetric and electrochemical impedance spectroscopic studies of the modified electrode (Au-DMAET-(SWCNT-PABS showed improved electron transfer over the bare Au electrode and the Au-DMAET in [Fe (CN6]3−/4− solution. The Au-DMAET-(SWCNT-PABS was used for the detection of Hg in water by square wave anodic stripping voltammetry (SWASV analysis at the following optimized conditions: deposition potential of −0.1 V, deposition time of 30 s, 0.1 M HCl electrolyte and pH 3. The sensor showed a good sensitivity and a limit of detection of 0.06 μM with a linear concentration range of 20 ppb to 250 ppb under the optimum conditions. The analytical applicability of the proposed method with the sensor electrode was tested with real water sample and the method was validated with inductively coupled plasma – optical emission spectroscopy.

  4. 十二烷基苯磺酸木薯淀粉酯微波法制备工艺研究%Preparation technology of dodecyl benzene sulfonic acid cassava starch ester by microwave

    Institute of Scientific and Technical Information of China (English)

    张利伟; 薛行华; 赵法敏; 张永强; 李光

    2013-01-01

    Dodecyl benzene sulfonic acid cassava starch ester was prepared by microwave method with cassava starch as the raw material , sodium dodecyl benzene sulfonate as the esterification agent and sodium hydroxide as the catalyst .The effects of synthetic condition , such as molar ratio ( sodi-um dodecyl benzene sulfonate to glucose unit of cassava starch ) , reaction time , incubated tempera-ture and pH value , on the substitution degree were investigated .The best conditions by orthogonal design were the molar ratio of sodium dodecyl benzene sulfonate to cassava at 0.06 , reaction time 5 h and the incubated temperature 80 ℃, at which the degree of substitution was 0.010 0 .FT-IR and XRD revealed the changes in the structure of the esterified starch , and TG analysis also dis-played the decline of the hydrophilic and thermal stability of the esterified starch .%  以木薯淀粉为原料,十二烷基苯磺酸钠为酯化剂,NaOH为催化剂,采用微波法制备十二烷基苯磺酸木薯淀粉酯,并考察其合成的工艺条件。探讨了十二烷基苯磺酸钠与木薯淀粉葡萄糖单元的摩尔比、反应时间、反应温度和pH值对产物取代度的影响,用正交实验分析对制备工艺进行优化,并通过红外、X射线和热重分析表征了酯化淀粉的结构及其热稳定性。结果表明,在十二烷基苯磺酸钠与木薯淀粉葡萄糖单元摩尔比为0.06、反应时间5 h、反应温度80℃和pH为10的条件下制备的十二烷基苯磺酸酯淀粉的取代度最佳,取代度为0.0100。红外和X射线谱图证明了酯化淀粉结构的改变,热重分析表明酯化淀粉亲水性与热稳定性有所下降。

  5. Electronic Conductivity of Polypyrrole−Dodecyl Benzene Sulfonate Complexes

    DEFF Research Database (Denmark)

    West, Keld; Bay, Lasse; Nielsen, Martin Meedom

    2004-01-01

    The electronic conductivity of the electroactive polymer polypyrrole-dodecyl benzene sulfonate (PPy-DBS) has been characterized as function of the redox level. The polymer was synthesized with different isomers of the dopant anions: the common mixed DBS tenside and three well-defined synthetic...... dodecyl isomers (with the benzene group at positions 1, 2 and 6). The conductivity was measured both by van der Pauw measurements on PPy-DBS in the oxidized, dry state as function of temperature, and by electrochemical impedance spectroscopy as function of potential in 0.1 M NaCl aqueous electrolyte...... carriers is at a minimum. The conductivity is further reduced because of the uptake of water at low potentials, creating electrolytic domains that separate the electronic domains and inhibit hopping. There is a pronounced hysteresis in the conductivity as a function of potential. However, the major part...

  6. Activated-sludge nitrification in the presence of linear and branched-chain alkyl benzene sulfonates.

    Science.gov (United States)

    Baillod, C R; Boyle, W C

    1968-01-01

    The effects of biodegradable linear alkyl benzene sulfonate and branched-chain alkyl benzene sulfonate detergents on activated-sludge nitrification were investigated by administering a synthetic waste containing up to 23 mg of each detergent per liter to eight bench-scale, batch, activated-sludge units. It was found that both detergents tended to promote complete oxidation of ammonia to nitrate, whereas control units produced approximately equal amounts of nitrite and nitrate. Various hypotheses are offered to explain the phenomenon.

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

    OpenAIRE

    1999-01-01

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

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

    Science.gov (United States)

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

    1987-04-01

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

  9. 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.

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

    Science.gov (United States)

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

    1994-03-01

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

  11. Pathomorphological changes in gills of fish fingerlings (Cirrhina mrigala) by linear alkyl benzene sulfonate.

    Science.gov (United States)

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

    1985-12-01

    Fish fingerlings (Cirrhina mrigala) exposed to 0.005 ppm (25% of LC50) concentration to detergents (linear alkyl benzene sulfonate) showed marked behavioral changes and distorted appearance of primary and secondary lamellae along with damage to gill epithelium under scanning electron microscopy at various magnifications. Mucosal cells of gills were found to secrete mucus showing primary reactions for membrane damage leading to dysfunction in respiration and osmoregulation.

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

    Science.gov (United States)

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

    2005-09-01

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

  13. 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.)

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

    Science.gov (United States)

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

    1981-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1989-07-01

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

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

    Science.gov (United States)

    Wu, Y; Shen, Y

    1992-01-01

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

  17. 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.

  18. 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.

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

    OpenAIRE

    2009-01-01

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

  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. (E)-4-[4-(Diethyl-amino)-benzyl-idene-ammonio]-benzene-sulfonate.

    Science.gov (United States)

    Ruanwas, Pumsak; Chantrapromma, Suchada; Fun, Hoong-Kun

    2012-07-01

    The title compound, C(17)H(20)N(2)O(3)S, synthesised from sulfanilic acid and 4-diethyl-amino-benzaldehyde, crystallized out as a zwitterion with the central N atom protonated. The zwitterion exists in an E conformation with respect to the C=N double bond. The dihedral angle between the benzene rings is 37.57 (5)°. In the crystal, the zwitterions are linked into a tape along the a axis by N-H⋯O hydrogen bonds. The crystal structure is further stabilized by weak C-H⋯O inter-actions and π-π inter-actions with a centroid-centroid distance of 3.8541 (6) Å. An O⋯O [2.8498 (11) Å] short contact is present.

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

    Science.gov (United States)

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

    2010-10-01

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

  3. Positional isomers of linear sodium dodecyl benzene sulfonate: solubility, self-assembly, and air/water interfacial activity.

    Science.gov (United States)

    Ma, Jian-Guo; Boyd, Ben J; Drummond, Calum J

    2006-10-10

    Commercial linear alkyl benzene sulfonates (ABS) are a very important class of anionic surfactants that are employed in a wide variety of applications, especially those involving wetting and detergency. Linear ABS surfactants generally consist of a complex mixture of different chain lengths and positional isomers. This diversity and level of complexity makes it difficult to develop fundamental structure-property correlations for the commercial surfactants. In this work, six monodisperse headgroup positional isomers of sodium para-dodecyl benzene sulfonate (Na-x-DBS, x = 1-6) have been studied. The influence of headgroup position and added electrolyte (NaCl) on the solubility and self-assembly (micellar and vesicular aggregation and lyotropic liquid crystalline phase behavior) in the temperature range from 10 to 90 degrees C have been investigated. Additionally, the air-aqueous solution interfacial adsorption at 25 (no added NaCl) and 50 degrees C (from 0 to 1.0 M added NaCl) has been examined. The observed physicochemical behavior is interpreted in terms of local molecular packing constraints, and in the case of the lyotropic liquid crystalline behavior global aggregate packing constraints as well.

  4. Urinary t,t-muconic acid, S-phenylmercapturic acid and benzene as biomarkers of low benzene exposure.

    Science.gov (United States)

    Fustinoni, Silvia; Buratti, Marina; Campo, Laura; Colombi, Antonio; Consonni, Dario; Pesatori, Angela C; Bonzini, Matteo; Farmer, Peter; Garte, Seymour; Valerio, Federico; Merlo, Domenico F; Bertazzi, Pier A

    2005-05-30

    This research compared the capability of urinary trans,trans-muconic acid (t,t-MA), S-phenylmercapturic acid (S-PMA) and benzene excreted in urine (U-benzene) to monitor low benzene exposure and evaluated the influence of smoking habit on these indices. Gasoline attendants, urban policemen, bus drivers and two groups of referents working in two large Italian cities (415 people) were studied. Median benzene exposure was 61, 22, 21, 9 and 6 microg/m3, respectively, with higher levels in workers than in referents. U-benzene, but not t,t-MA and S-PMA, showed an exposure-related increase. All the biomarkers were strongly influenced by cigarette smoking, with values up to five-fold higher in smokers compared to non-smokers. In conclusion, in the range of investigated benzene exposure (<478 microg/m3 or <0.15 ppm), the smoking habit may be regarded as a major source of benzene intake; among the study indices, U-benzene is the marker of choice for the biological monitoring of occupational and environmental exposure.

  5. 40 CFR 417.140 - Applicability; description of the neutralization of sulfuric acid esters and sulfonic acids...

    Science.gov (United States)

    2010-07-01

    ... neutralization of sulfuric acid esters and sulfonic acids subcategory. 417.140 Section 417.140 Protection of... MANUFACTURING POINT SOURCE CATEGORY Neutralization of Sulfuric Acid Esters and Sulfonic Acids Subcategory § 417.140 Applicability; description of the neutralization of sulfuric acid esters and sulfonic...

  6. 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...

  7. N-(4-Hydroxy­phen­yl)benzene­sulfon­amide

    OpenAIRE

    Khan, Islam Ullah; Mariam, Irfana; Zia-ur-Rehman, Muhammad; Arif Sajjad, Muhammad; Sharif, Shahzad

    2010-01-01

    The title compound, C12H11NO3S, synthesized by the reaction of benzene sulfonyl chloride with para-amino­phenol, is of inter­est as a precursor to biologically active sulfur-containing heterocyclic compounds. The structure is stabilized by N—H⋯O and O—H⋯O hydrogen bonds.

  8. Synergistic flame retardant effects of composites containing organic montmorillonite, Nylon 6 and 2-cyclic pentaerythritoloctahydrogen tetraphosphate-4,6-benzene sulfonic acid sodium ammion-triazine%新型单组份磷-氮膨胀型阻燃剂/OMMT对尼龙6热稳定性能的影响及其协同阻燃效果

    Institute of Scientific and Technical Information of China (English)

    王超; 李迎春; 胡国胜; 曹东豪

    2015-01-01

    A novel P-N containing intumescent flame retardant, 2-cyclic pentaerythritoloctahydrogen tetraphosphate-4,6-benzene sulfonic acid sodium ammion-triazine ( CTOB) was synthesized and used as an additive in intumescent flame retardant composites containing organic montmorillonite (OMMT) and Nylon 6. The thermal stability and flammability properties of Nylon 6, CTOB, OMMT and their composites were investigated by TGA, limiting oxygen index ( LOI) and cone calorimeter tests. Synergistic effects between CTOB and OMMT in the Nylon 6/CTOB/OMM composite were observed. A combination of CTOB and OMMT improved the thermal stability and the flammability properties of Nylon 6 and increased the LOI value to 28. 0%. The average and peak heat release rates of the ternary composite were reduced by about 65. 7 and 49. 3%, respectively, compared with those of Nylon 6. The residue generated after the cone calorimeter tests upon combustion of the ternary composite was a compact and dense char as revealed by SEM, which is critically important for an excellent flame retardant.%合成出新型单组份磷-氮膨胀型阻燃剂2-环季戊四醇磷酸酯-4,6-对氨基苯磺酸钠均三嗪(CTOB),通过FT-IR,1H NMR和31 P NMR对其结构进行表征。以CTOB与有机蒙脱土( OMMT)为原料,制备出阻燃型CTOB/ OMMT/ Nylon 6复合材料。热重分析表明:CTOB和OMMT的加入能有效提高尼龙6的热稳定性能和成炭性能,通过极限氧指数( LOI)、锥形量热、垂直燃烧实验(UL-94)和TGA对CTOB/ OMMT/ Nylon 6复合材料的阻燃性能进行研究。结果表明,CTOB和 OMMT在尼龙6中表现出良好的协同阻燃效果,CTOB/OMMT/ Nylon 6的氧指数可达28.0%,垂直燃烧性能达到UL-94 V-0级,阻燃后的尼龙6其PHRR 和 THR分别下降了65.7%和49.3%。 CTOB/ OMMT/ Nylon 6燃烧后,表面可生成致密性良好的膨胀炭层,膨胀炭层的形成是有效提高Nylon 6阻燃性能的关键因素。

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

    OpenAIRE

    ALKAN, Cemil; YURTSEVEN, Nebahat; ARAS, Leyla

    2005-01-01

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

  10. 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.

  11. 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.

  12. 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.

  13. 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).

  14. Phosphoric Acid-Mediated Synthesis of Vinyl Sulfones through Decarboxylative Coupling Reactions of Sodium Sulfinates with Phenylpropiolic Acids.

    Science.gov (United States)

    Rong, Guangwei; Mao, Jincheng; Yan, Hong; Zheng, Yang; Zhang, Guoqi

    2015-08-07

    A novel phosphoric acid -mediated synthesis of vinyl sulfones through decarboxylative coupling reactions of sodium sulfinates with phenylpropiolic acids is described. This transformation is efficient and environmentally friendly.

  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. 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.

  17. Pharmacokinetic comparisons of Paeoniflorin and Paeoniflorin-6'O-benzene sulfonate in rats via different routes of administration.

    Science.gov (United States)

    Wang, Chun; Yuan, Jun; Zhang, Ling Ling; Wei, Wei

    2016-12-01

    1. The pharmacokinetics study of Paeoniflorin (Pae) and its acylated derivative (CP-25) was performed. 2. The structure of CP-25 was identified by mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR). The rats were injected with CP-25(6, 12, 24 mg/kg) and orally treated with CP-25 (32, 64, 128 mg/kg), respectively. An high-performance liquid chromatography (HPLC) assay was developed to determine the plasma concentrations of Pae and CP-25. 3. The results of MS and NMR showed that the acylated product was Pae-6'O-benzene sulfonate (CP-25). The plasma levels in oral CP-25 groups were detectable, whereas those of Pae in the oral groups (25 and 50 mg/kg) were undetectable. More specifically, the Cmax values of oral CP-25 were 0.12, 0.19 and 0.44 μg/ml, and the corresponding t1/2β of CP-25 were 1.44, 2.12 and 2.11 h, respectively. In addition, the t1/2β values of intravenous CP-25 were 161.99, 152.81 and 153.76 min, respectively. 4. Compared with the venous pharmacokinetics parameters of Pae, those of the t1/2β, MRT, Vd and CL/F in the CP-25 groups increased noticeably. As expected, compared with oral parameters of Pae, those of t1/2a, t1/2β, AUC, MRT and Vd in the CP-25 group increased obviously. Finally, the absolute bioavailability of Pae and CP-25 were 3.6 and 10.6%, respectively. 5. Our results indicate that CP-25 is characterized by improved absorption, well distribution, lower clearance, long mean residence time, and moderate bioavailability in rats.

  18. 40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

    Science.gov (United States)

    2010-07-01

    ... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737)...

  19. Characteristics of polyaniline electropolymerized in camphor sulfonic acid

    Energy Technology Data Exchange (ETDEWEB)

    Santos, J.R. Jr. [Instituto de Quimica de Sao Carlos/DFQ/USP, C.P. 369, 13560-970, Sao Carlos, SP (Brazil); Malmonge, J.A. [Instituto de Fisica de Sao Carlos/DFCM/USP, C.P. 369, 13560-970, Sao Carlos, SP (Brazil); Conceicao Silva, A.J.G. [Instituto de Fisica de Sao Carlos/DFCM/USP, C.P. 369, 13560-970, Sao Carlos, SP (Brazil); Motheo, A.J. [Instituto de Quimica de Sao Carlos/DFQ/USP, C.P. 369, 13560-970, Sao Carlos, SP (Brazil); Mascarenhas, Y.P. [Instituto de Fisica de Sao Carlos/DFCM/USP, C.P. 369, 13560-970, Sao Carlos, SP (Brazil); Mattoso, L.H.C. [Instituto de Fisica de Sao Carlos/DFCM/USP, C.P. 369, 13560-970, Sao Carlos, SP (Brazil)

    1995-03-01

    Polyaniline was electropolymerized by cyclic voltammetry in the presence of camphor sulfonic acid (CSA), and the resulting film was characterized by solubility tests, UV-Vis absorption, electron microscopy, X-ray diffraction and conductivity measurements. The use of the functionalized acid - CSA - made it possible to obtain the as-electropolymerized polymer (in the doped state) soluble in organic solvents such as m-cresol and chloroform. The UV-Vis spectra of PAni-CSA in m-cresol presented a free-carrier tail commencing at 1000nm which may be attributed to secondary doping due to conformational changes of the polymer chains. After treatment with m-cresol the film exhibited an increase of conductivity reaching ca. 100S/cm. (orig.)

  20. 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.

  1. 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)

  2. 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.

  3. 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.

  4. 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.

  5. Mouse model of ulcerative colitis using trinitrobenzene sulfonic acid

    Directory of Open Access Journals (Sweden)

    Irfan Ahmad Rather

    2015-12-01

    Full Text Available Animal model of intestinal inflammation is of paramount significance that aids in discerning the pathologies underlying ulcerative colitis and Crohn’s disease, the two clinical presentations of inflammatory bowel disease. The 2,4,6-trinitrobenzene sulfonic acid (TNBS colitis model represents one such intestinal inflammation-prototype that is generated in susceptible strains of mice through intra-rectal instillation of compound TNBS. In this paper, we demonstrate the experimental induction of TNBS-mediated colitis in a susceptible strain of ICR mice. This can be done by the following steps: a acclimation, b induction and c observation. TNBS-mouse model provides the information in shortest possible time and simultaneously represents a cost effective and highly reproducible model method of studying the pathogenesis of inflammatory bowel disease.

  6. Preparation and characterization of polyaniline microrods synthesized by using dodecylbenzene sulfonic acid and periodic acid

    OpenAIRE

    TAŞ, RECEP; Can, Muzaffer; Sönmezoğlu, Savaş

    2015-01-01

    The preparation of polyaniline (PANI) microrod arrays in the presence of dodecylbenzene sulfonic acid (DBSAH), a structure-directing agent, and in the presence of periodic acid (H$_{5}$IO$_{6})$, an oxidant in aqua-acidic media, was investigated. DBSAH was performed to distinguish the roles of both surfactant and dopant. The method of preparation of DBSAH and H$_{5}$IO$_{6}$ doped PANI (DBSAH-PANI) microrods in a reversed micelle had previously not been reported. The characterizations of the ...

  7. Radiation-chemical synthesis of polypropylene fabrics with sulfonic acid functional groups

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Hyun Kug; Park, Jung Soo; Han, Do Hung, E-mail: dhhan@yumail.ac.kr; Bondar, Iuliia, E-mail: juliavad@yahoo.co

    2011-04-01

    A sorption-active material carrying sulfonic acid groups was synthesized by the radiation-induced graft polymerization of styrene monomer onto the surface of non-woven polypropylene fabric, followed by sulfonation of the grafted polystyrene chains. The effect of the main experimental parameters (absorbed dose, monomer concentration, reaction time) on the styrene degree of grafting was investigated. The sulfonation process with 5% chlorosulfonic acid at room temperature was investigated in detail and the optimal sulfonation conditions for the samples with a medium degree of grafting (70-140%) were determined. Densities of 3.5-5 meq/g were obtained by applying those sorption-active PP fabrics with a sulfonic acid group.

  8. Cationic and radical intermediates in the acid photorelease from aryl sulfonates and phosphates.

    Science.gov (United States)

    Terpolilli, Marco; Merli, Daniele; Protti, Stefano; Dichiarante, Valentina; Fagnoni, Maurizio; Albini, Angelo

    2011-01-01

    The irradiation of a series of phenyl sulfonates and phosphates leads to the quantitative release of acidity with a reasonable quantum yield (≈0.2). Products characterization, ion chromatography analysis and potentiometric titration are consistent with the intervening of two different paths in this reaction, viz. cationic with phosphates and (mainly) radical with sulfonates.

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

    Institute of Scientific and Technical Information of China (English)

    弋冰; 王德义; 李泽军

    2001-01-01

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

  10. 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.

  11. Anaerobic degradation of benzene by enriched consortia with humic acids as terminal electron acceptors

    Energy Technology Data Exchange (ETDEWEB)

    Cervantes, Francisco J., E-mail: fjcervantes@ipicyt.edu.mx [Division de Ciencias Ambientales, Instituto Potosino de Investigacion Cientifica y Tecnologica (IPICyT), Camino a la Presa San Jose 2055, Col. Lomas 4a. Seccion, San Luis Potosi, SLP, 78216 Mexico (Mexico); Mancilla, Ana Rosa; Toro, E. Emilia Rios-del [Division de Ciencias Ambientales, Instituto Potosino de Investigacion Cientifica y Tecnologica (IPICyT), Camino a la Presa San Jose 2055, Col. Lomas 4a. Seccion, San Luis Potosi, SLP, 78216 Mexico (Mexico); Alpuche-Solis, Angel G.; Montoya-Lorenzana, Lilia [Division de Biologia Molecular, Instituto Potosino de Investigacion Cientifica y Tecnologica (IPICyT), Camino a la Presa San Jose 2055, Col. Lomas 4a. Seccion, San Luis Potosi, SLP, 78216 Mexico (Mexico)

    2011-11-15

    Highlights: {yields} Enriched consortia were able to couple the anaerobic degradation of benzene to the reduction of humic acids. {yields} Electron-equivalents derived from anaerobic benzene oxidation were highly recovered as reduced humic acids. {yields} Several species from classes {beta}-, {delta}- and {gamma}-Proteobacteria were enriched during the anaerobic degradation of benzene. - Abstract: The anaerobic degradation of benzene coupled to the reduction of humic acids (HA) was demonstrated in two enriched consortia. Both inocula were able to oxidize benzene under strict anaerobic conditions when the humic model compound, anthraquinone-2,6-disulfonate (AQDS), was supplied as terminal electron acceptor. An enrichment culture originated from a contaminated soil was also able to oxidize benzene linked to the reduction of highly purified soil humic acids (HPSHA). In HPSHA-amended cultures, 9.3 {mu}M of benzene were degraded, which corresponds to 279 {+-} 27 micro-electron equivalents ({mu}Eq) L{sup -1}, linked to the reduction of 619 {+-} 81 {mu}Eq L{sup -1} of HPSHA. Neither anaerobic benzene oxidation nor reduction of HPSHA occurred in sterilized controls. Anaerobic benzene oxidation did not occur in soil incubations lacking HPSHA. Furthermore, negligible reduction of HPSHA occurred in the absence of benzene. The enrichment culture derived from this soil was dominated by two {gamma}-Proteobacteria phylotypes. A benzene-degrading AQDS-reducing enrichment originated from a sediment sample showed the prevalence of different species from classes {beta}-, {delta}- and {gamma}-Proteobacteria. The present study provides clear quantitative demonstration of anaerobic degradation of benzene coupled to the reduction of HA.

  12. Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) contamination from textiles.

    Science.gov (United States)

    Supreeyasunthorn, Phenpimuk; Boontanon, Suwanna K; Boontanon, Narin

    2016-01-01

    The goals of this study were to determine the concentrations of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in textiles and to determine PFOS and PFOA contamination in textile washing water. Quantification analysis was performed by high performance liquid chromatography coupled with tandem mass spectrometry. Analysis of 32 textile samples by methanol extraction revealed that the average concentrations of PFOS and PFOA were 0.18 µg m(-2) (0.02 to 0.61 µg m(-2)) and 2.74 µg m(-2) (0.31 to 14.14 µg m(-2)), respectively. Although the average concentration of PFOS found in textile samples was below European Union (EU) Commission regulations (textile samples had PFOA concentrations exceeding 1 µg m(-2). Thus, based on these results, the concentration of PFOA in products should also be regulated. Experiments on PFOS and PFOA leaching into washing water were conducted. The maximum concentrations of PFOS and PFOA were measured after the first washing; the concentrations gradually decreased with each subsequent washing. PFOS and PFOA migrated from textiles and were released into the environment, with disappearance percentages of 29.8% for PFOS and 99% for PFOA. The data presented in this study showed that textiles could be a significant direct and indirect source of PFOS and PFOA exposure for both humans and the environment.

  13. 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.

  14. 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.

  15. 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.

  16. Camphor Sulfonic Acid-hydrochloric Acid Codoped Polyaniline/polyvinyl Alcohol Composite: Synthesis and Characterization

    OpenAIRE

    Jorge Enrique Osorio-Fuente; Carlos Gómez-Yáñez; María de los Ángeles Hernández-Pérez; Fidel Pérez-Moreno

    2014-01-01

    A complementary dopant system formed by hydrochloric and camphor sulfonic (CSA) acids was used in the in-situ synthesis of a polyaniline (PANi)/polyvinyl alcohol (PVA) composite. The conductivity measurements showed that the use of CSA either as single dopant or codopant caused a decrement up to 2 orders of magnitude on the overall conductivity as well as an improvement on thermal stability. The PANi/PVA composites were characterized by spectroscopic and thermal analysis. Conducting emeraldin...

  17. Poly(p-Phenylene Sulfonic Acids). PEMs with frozen-in free volume

    Energy Technology Data Exchange (ETDEWEB)

    Litt, Morton [Case Western Reserve Univ., Cleveland, OH (United States)

    2016-01-21

    Early work with rigid rod aromatic polyelectrolytes implied that steric hindrance in packing of the rigid rods left unoccupied volumes that could absorb and hold water molecules strongly. We called this “frozen in free volume). It is illustrated and contrasted with the packing of flexible backbone polyelectrolytes (Reference 5 of this report). This was quantified for poly(biphenylene disulfonic acid) (PBDSA) and poly(phenylene disulfonic acid) (PPDSA). We found that PPDSA held three water molecules per acid group down to 11% relative humidity (RH) and had very high conductivity even at these low RHs. (Reference 1 of report.) The frozen-in free volume was calculated to be equivalent to a λ of 3.5. The work reported below concentrated on studying these polymers and their copolymers with biphenylene disulfonic acid. As expected, the polyelectrolytes are water soluble. Several approaches towards making water stable films were studied. Grafting alkyl benzene substituents on sulfonic acid groups had worked for PBPDSA (1) so it was tried with PPDSA and a 20%/80% copolymer of BPDSA and PDSA (B20P80). T-butyl, n-octyl and n-dodecyl benzene were grafted. Good films could be made. Water absorption and conductivity were studied as a function of RH and temperature (Reference 2). When less than 20% of the sulfonic acid groups were grafted, conductivity was much higher than that of Nafion NR212 at all RHs. At low graft levels, conductivity was ten times higher. Mechanical properties and swelling were acceptable below 90% RH. However, all the films were unstable in water and slowly disintegrated. The proposed explanation was that the molecules formed nano-aggregates in solution held together by hydrophobic bonding. Their cast films disintegrated when placed in water since hydrophobic bonding between the nano-aggregates was poor. We then shifted to crosslinking as a method to produce water stable films (References 3 and 4). Biphenyl could easily be reacted with the polymer

  18. Poly(p-Phenylene Sulfonic Acids). PEMs with frozen-in free volume

    Energy Technology Data Exchange (ETDEWEB)

    Litt, Morton [Case Western Reserve Univ., Cleveland, OH (United States)

    2016-01-21

    Early work with rigid rod aromatic polyelectrolytes implied that steric hindrance in packing of the rigid rods left unoccupied volumes that could absorb and hold water molecules strongly. We called this “frozen in free volume). It is illustrated and contrasted with the packing of flexible backbone polyelectrolytes (Reference 5 of this report). This was quantified for poly(biphenylene disulfonic acid) (PBDSA) and poly(phenylene disulfonic acid) (PPDSA). We found that PPDSA held three water molecules per acid group down to 11% relative humidity (RH) and had very high conductivity even at these low RHs. (Reference 1 of report.) The frozen-in free volume was calculated to be equivalent to a λ of 3.5. The work reported below concentrated on studying these polymers and their copolymers with biphenylene disulfonic acid. As expected, the polyelectrolytes are water soluble. Several approaches towards making water stable films were studied. Grafting alkyl benzene substituents on sulfonic acid groups had worked for PBPDSA (1) so it was tried with PPDSA and a 20%/80% copolymer of BPDSA and PDSA (B20P80). T-butyl, n-octyl and n-dodecyl benzene were grafted. Good films could be made. Water absorption and conductivity were studied as a function of RH and temperature (Reference 2). When less than 20% of the sulfonic acid groups were grafted, conductivity was much higher than that of Nafion NR212 at all RHs. At low graft levels, conductivity was ten times higher. Mechanical properties and swelling were acceptable below 90% RH. However, all the films were unstable in water and slowly disintegrated. The proposed explanation was that the molecules formed nano-aggregates in solution held together by hydrophobic bonding. Their cast films disintegrated when placed in water since hydrophobic bonding between the nano-aggregates was poor. We then shifted to crosslinking as a method to produce water stable films (References 3 and 4). Biphenyl could easily be reacted with the polymer

  19. The use of S-phenylmercapturic acid as a biomarker in molecular epidemiology studies of benzene.

    Science.gov (United States)

    Farmer, Peter B; Kaur, Balvinder; Roach, Jonathan; Levy, Len; Consonni, Dario; Bertazzi, Pietro A; Pesatori, Angela; Fustinoni, Silvia; Buratti, Marina; Bonzini, Matteo; Colombi, Antonio; Popov, Todor; Cavallo, Domenico; Desideri, Arianna; Valerio, Federico; Pala, Mauro; Bolognesi, Claudia; Merlo, Franco

    2005-05-30

    S-Phenylmercapturic acid (S-PMA), is a urinary metabolite of benzene, thought to be derived from the condensation product of benzene oxide with glutathione. S-PMA may be determined by GC, HPLC (UV or fluorescence detection), GC-MS, LC-MS/MS or immunoassays. The limit of sensitivities of most of these techniques is 1 microg/l urine or below. It has been suggested that S-PMA may have value as a biomarker for low level human exposure to benzene, in view of the facts that urinary excretion of S-PMA has been found to be related to airborne benzene in occupationally exposed workers, and that only low background levels of S-PMA have been found in control subjects. We have evaluated the use of S-PMA as a biomarker, using a commercially available analytical service, in a multicentre European study of populations exposed to varying levels of benzene, in Italy (Milan, Genoa) and in Bulgaria (Sofia). These were filling station attendants, urban policemen, bus drivers, petrochemical workers and referents (a total of 623 subjects). S-PMA was measured at the end of the work shift by an immunoassay procedure. Urinary benzene (in Milan only) and the benzene metabolite trans,trans-muconic acid (t,t-MA) were measured before and after the work shift. Air-borne benzene was measured as a monitor of exposure. Urinary benzene was the most discriminatory biomarker and showed a relationship with airborne benzene at all levels of exposure studied (including groups exposed to <0.1 ppm benzene), whereas t,t-MA and S-PMA, as determined by immunoassay, were suitable only in the highest exposed workers (petrochemical industry, geometric mean 1765 microg/m3 (0.55 ppm) benzene). All three biomarkers were positively correlated with smoking as measured by urinary cotinine).

  20. The Study on the Role of Intestinal Microecology Protecting Tight Junction Protein Between the Epithelial Cells of Intestinal Mucosal Barrier in Rats with Trinitro-Benzen-Sulfonic Acid Induced Colitis%肠道微生态对三硝基苯磺酸诱导大鼠结肠炎肠黏膜上皮细胞紧密连接蛋白occludin保护作用的研究

    Institute of Scientific and Technical Information of China (English)

    张文远; 姜伟炜

    2010-01-01

    目的 研究肠道微生态对三硝基苯磺酸(trinitro-benzen-sulfonic acid,TNBS)诱导大鼠结肠炎肠黏膜上皮细胞紧密连接蛋白的保护作用.方法 建立TNBS诱导大鼠结肠炎模型.实验分为正常组、模型组和双歧杆菌嗜酸乳杆菌肠球菌三联活菌(金双歧)组.进行疾病活动指数(DAI)和组织学损伤评分,用ELISA法测定结肠组织TNF-α、IL-10和血清内毒素水平,采用免疫组织化学染色检测紧密连接(tight junction,TJ)相关蛋白occludin的分布.结果 TNBS诱导大鼠结肠炎后,DAI和组织学损伤评分增高,结肠组织TNF-α水平升高,IL-10水平降低和血清内毒水平升高,而经双歧杆菌嗜酸乳杆菌肠球菌三联活菌处理后,DAI和组织学损伤评分有明显下降,结肠组织TNF-α水平降低,IL-10水平升高和血清内毒素水平降低,组间比较差异有显著性(P<0.05).TNBS诱导大鼠结肠炎后,TJ结构遭到破坏,TJ相关蛋白的表达亦减少,而双歧杆菌嗜酸乳杆菌肠球菌三联活菌(金双歧)处理后可使TNBS引起的TJ结构受损减轻,相关蛋白的表达增多(P<0.05).结论 肠道微生态对TNBS诱导大鼠结肠炎肠黏膜上皮细胞TJ蛋白具有明显的保护作用,其可能的机制是通过纠正肠道微生态,上调肠上皮细胞TJ蛋白occludin的表达,降低结肠组织TNF-α水平,提高IL-10水平,从而抑制内毒素通过紧密连接进入体循环.

  1. Laser photolysis of interaction of poly-guanylic acid (5′) with anthraquinone-2-sulfonate

    Institute of Scientific and Technical Information of China (English)

    马建华; 林维真; 王文峰; 韩镇辉; 姚思德; 林念芸

    2002-01-01

    The electron transfer reaction between triplet anthraquinone-2-sulfonate and poly- guanylic acid (5′) in CH3CN-H2O (97:3) has been investigated by 248 nm (KrF) laser flash photolysis. The transient absorption spectra and kinetics obtained from the interaction of triplet anthraquinone-2-sulfonate and poly[G] demonstrate that the primary ionic radical pair, radical cation of poly[G] and radical anion of anthraquinone-2-sulfonate have been detected simultaneously. The free energy changes in the process of the electron transfer were also calculated.

  2. 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.

  3. 三烷基胺萃取氨基磺酸及其废水的特性研究%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′Cdisulfonic 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.

  4. sp³ -linked amorphous carbon with sulfonic acid groups as a heterogeneous acid catalyst.

    Science.gov (United States)

    Suganuma, Satoshi; Nakajima, Kiyotaka; Kitano, Masaaki; Hayashi, Shigenobu; Hara, Michikazu

    2012-09-01

    SO₃H-bearing amorphous carbon prepared from polyvinyl chloride (PVC) is studied as a heterogeneous Brønsted acid catalyst. Sulfonation of partially carbonized PVC produces amorphous carbon consisting of small SO₃H-bearing carbon sheets linked by sp³ -based aliphatic hydrocarbons. This carbon material exhibits much higher catalytic performance in the hydrolysis of cellobiose than conventional heterogeneous Brønsted acid catalysts with SO₃H groups, including SO₃H-bearing amorphous carbon derived from cellulose. This can be attributed to a high density of SO₃H groups and the fast diffusion of reactants and products enabled by a flexible carbon network.

  5. Dual Role of Endogenous Serotonin in 2,4,6-Trinitrobenzene Sulfonic Acid-Induced Colitis

    Science.gov (United States)

    Rapalli, Alberto; Bertoni, Simona; Arcaro, Valentina; Saccani, Francesca; Grandi, Andrea; Vivo, Valentina; Cantoni, Anna M.; Barocelli, Elisabetta

    2016-01-01

    Background and Aims: Changes in gut serotonin (5-HT) content have been described in Inflammatory Bowel Disease (IBD) and in different experimental models of colitis: the critical role of this monoamine in the pathogenesis of chronic gastrointestinal inflammation is gradually emerging. Aim of the present study was to evaluate the contribution of endogenous 5-HT through the activation of its specific receptor subtypes to the local and systemic inflammatory responses in an experimental model of IBD. Materials and Methods: Colitis was induced by intrarectal 2,4,6-TriNitroBenzene Sulfonic acid in mice subacutely treated with selective antagonists of 5-HT1A (WAY100135), 5-HT2A (Ketanserin), 5-HT3 (Ondansetron), 5-HT4 (GR125487), 5-HT7 (SB269970) receptors and with 5-HT1A agonist 8-Hydroxy-2-(di-n-propylamino)tetralin. Results: Blockade of 5-HT1A receptors worsened TNBS-induced local and systemic neutrophil recruitment while 5-HT1A agonist delayed and mitigated the severity of colitis, counteracting the increase in colonic 5-HT content. On the contrary, blockade of 5-HT2A receptors improved global health conditions, reduced colonic morphological alterations, down-regulated neutrophil recruitment, inflammatory cytokines levels and colonic apoptosis. Antagonism of 5-HT3, 5-HT4, and 5-HT7 receptor sites did not remarkably affect the progression and outcome of the pathology or only slightly improved it. Conclusion: The prevailing deleterious contribution given by endogenous 5-HT to inflammation in TNBS-induced colitis is seemingly mediated by 5-HT2A and, to a lesser extent, by 5-HT4 receptors and coexists with the weak beneficial effect elicited by 5-HT1A stimulation. These findings suggest how only a selective interference with 5-HT pro-inflammatory actions may represent an additional potential therapeutic option for intestinal inflammatory disorders. PMID:27047383

  6. Dual role of endogenous serotonin in 2,4,6-trinitrobenzene sulfonic acid-induced colitis

    Directory of Open Access Journals (Sweden)

    Alberto eRapalli

    2016-03-01

    Full Text Available Background and Aims: Changes in gut serotonin content have been described in Inflammatory Bowel Disease and in different experimental models of colitis: the critical role of this monoamine in the pathogenesis of chronic gastrointestinal inflammation is gradually emerging. Aim of the present study was to evaluate the contribution of endogenous serotonin through the activation of its specific receptor subtypes to the local and systemic inflammatory responses in an experimental model of Inflammatory Bowel Disease. Methods: Colitis was induced by intrarectal 2,4,6-TriNitroBenzene Sulfonic acid in mice subacutely treated with selective antagonists of 5-HT1A (WAY100135, 5-HT2A (Ketanserin, 5-HT3 (Ondansetron, 5-HT4 (GR125487, 5-HT7 (SB269970 receptors and with 5-HT1A agonist 8-Hydroxy-2-(di-n-propylaminotetralin. Results: Blockade of 5-HT1A receptors worsened TNBS-induced local and systemic neutrophil recruitment while 5-HT1A agonist delayed and mitigated the severity of colitis, counteracting the increase in colonic 5-HT content. On the contrary, blockade of 5-HT2A receptors improved global health conditions, reduced colonic morphological alterations, down-regulated neutrophil recruitment, inflammatory cytokines levels and colonic apoptosis. Antagonism of 5-HT3, 5-HT4 and 5-HT7 receptor sites did not remarkably affect the progression and outcome of the pathology or only slightly improved it.Conclusions: The prevailing deleterious contribution given by endogenous serotonin to inflammation in TNBS-induced colitis is seemingly mediated by 5-HT2A and, to a lesser extent, by 5-HT4 receptors and coexists with the weak beneficial effect elicited by 5-HT1A stimulation. These findings suggest how only a selective interference with 5-HT pro-inflammatory actions may represent an additional potential therapeutic option for intestinal inflammatory disorders.

  7. Photoinduced Electron Transfer Reaction between Poly-guanylic Acid (5`) with Anthraquinone-2-sulfonate

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The electron transfer reaction between triplet anthraquinone-2-sulfonate with poly-guanylic acid (5) (poly[G]) in acetonitrile-H2O has been investigated by 248 nm laser flash photolysis. The transient absorption spectra of radical cation of poly[G] and radical anion of anthraqunione-2-sulfonate(AQS) arising from electron transfer reaction has been observed simultaneously for the first time. The formation processes of radical cation of poly[G] and radical anion of anthraquinone-2-sulfonate as well as the decay processes of triplet anthraquinone-2-sulfonate have also been observed, the apparent rate constants for the formation and decay of transient species have been determined. The free energy changes in the process of the electron transfer was also calculated.

  8. Silica-supported sulfonic acids as recyclable catalyst for esterification of levulinic acid with stoichiometric amounts of alcohols

    Directory of Open Access Journals (Sweden)

    Raimondo Maggi

    2016-10-01

    Full Text Available Converting biomass into value-added chemicals holds the key to sustainable long-term carbon resource management. In this context, levulinic acid, which is easily obtained from cellulose, is valuable since it can be transformed into a variety of industrially relevant fine chemicals. Here we present a simple protocol for the selective esterification of levulinic acid using solid acid catalysts. Silica supported sulfonic acid catalysts operate under mild conditions and give good conversion and selectivity with stoichiometric amounts of alcohols. The sulfonic acid groups are tethered to the support using organic tethers. These tethers may help in preventing the deactivation of the active sites in the presence of water.

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

    Energy Technology Data Exchange (ETDEWEB)

    Ames, Richard L. [Colorado School of Mines, Golden, CO (United States)

    2004-09-01

    Perfluoro ionomer membranes are tetrafluoro ethylene-based materials with microheterogeneous structures consisting of a hydrophobic polymer backbone and a hydrophilic side-chain cluster region. Due to the ionomer cluster morphology, these films exhibit unique transport properties. Recent investigations with perfluoro sulfonate and perfluoro sulfonate/carboxylate composite polymers have demonstrated their value in the dehydration of nitric acid and they show potential as an alternative to conventional, energy intensive unit operations in the concentration of acid feeds. As a result, investigations were conducted to determine the feasibility of using pure perfluoro carboxylate and mixed perfluoro sulfonate/carboxylate films for the dehydration of nitric acid because of the speculation of improved water selectivity of the carboxylate pendant chain. During the first phase of these investigations the effort was focused on generating a thin, solution cast perfluoro carboxylate ionomer film, to evaluate the general, chemical and physical characteristics of the polymer, and to assess the material's aqueous transport performance (flux and nitrate separation efficiencies) in pervaporation and high-pressure environments. Results demonstrated that generating robust solution-cast films was difficult yet a number of membranes survived high trans-membrane pressures up to 700 psig. General characterization of the solution cast product showed reduced ion exchange capacities when compared with thicker, ''as received'' perfluoro carboxylate and similar sulfonate films. Small angle x-ray scattering analysis results suggested that the solution cast carboxylate films contained a small fraction of sulfonate terminated side-chains. Aqueous transport experimentation showed that permeate fluxes for both pure water and nitric acid were approximately two orders of magnitude smaller for the carboxylate solution cast membranes when compared to their sulfonate

  10. Accumulation potentials of perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkyl sulfonic acids (PFSAs) in maize (Zea mays).

    Science.gov (United States)

    Krippner, Johanna; Falk, Sandy; Brunn, Hubertus; Georgii, Sebastian; Schubert, Sven; Stahl, Thorsten

    2015-04-15

    Uptake of perfluoroalkyl acids (PFAAs) by maize represents a potential source of exposure for humans, either directly or indirectly via feed for animals raised for human consumption. The aim of the following study was, therefore, to determine the accumulation potential of perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkyl sulfonic acids (PFSAs) in maize (Zea mays). Two different concentrations of PFAAs were applied as aqueous solution to the soil to attain target concentrations of 0.25 mg or 1.00 mg of PFAA per kg of soil. Maize was grown in pots, and after harvesting, PFAA concentrations were measured in the straw and kernels of maize. PFCA and PFSA concentrations of straw decreased significantly with increasing chain length. In maize kernels, only PFCAs with a chain length ≤ C8 as well as perfluorobutanesulfonic acid (PFBS) were detected. The highest soil-to-plant transfer for both straw and kernels was determined for short-chained PFCAs and PFSAs.

  11. 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.

  12. Morphogenetic control of calcite crystal growth in sulfonic acid based hydrogels.

    Science.gov (United States)

    Grassmann, Olaf; Löbmann, Peer

    2003-03-17

    In this paper the mineralization of CaCO(3) in various hydrogel matrices is presented. Sulfonic acid based hydrogels were prepared by introduction of sulfonate-containing monomers into a polyacrylamide network. The sulfonate content of polyacrylamide-co-vinylsulfonate and polyacrylamide-co-allylsulfonate decreases during elution of the copolymers in demineralized water, indicating insufficient linking of the sulfonate-bearing monomers within the hydrogel. In contrast to this, acrylamidomethylpropanesulfonate (AMPS) effectively copolymerizes with acrylamide (AAm) monomers. To study the influence of spatial arrangement of ionic functional groups within hydrogel networks on the mineralization of CaCO(3), AMPS copolymers with different degrees of AMPS cross-linking were synthesized. For the mineralization experiments the copolymers were placed into a double-diffusion arrangement. Calcite as the thermodynamically stable modification of CaCO(3) was obtained with a particular morphology. The pseudocubic habitus resembles aggregates obtained by mineralization in pure polyacrylamide. However, closer examination of the aggregates by scanning electron microscopy (SEM) shows that the crystal growth in the AMPS copolymers is different from that observed in polyacrylamide. Whereas the morphology of the calcite aggregates could be fine-tuned by using copolymers with different sulfonate content, the spatial distribution of the ionic functional groups alters the course of crystallization. Calcium ions are locally accumulated due to the heterogeneous distribution of functional sulfonate groups within the copolymer network. Thereby the nucleation of calcite is triggered, resulting in enhanced mineralization.

  13. Charge transport in conducting polyaniline co-doped with sulfosalicylic acid and dodecylbenzoyl sulfonic acid

    Institute of Scientific and Technical Information of China (English)

    MA Li; YAN Jun; GAN Meng-Yu; HE Ling; LI Jian-Feng

    2009-01-01

    We prepared conducting polyaniline (PAn) co-doped with sulfosalicylic acid (SSA) and dodecylbenzoyl sulfonic acid (DBSA) in micro-emulsive polymerization, and studied its charge transport behaviors based on the measurement of its electrical conductivity in the temperature range between 203 K and 298 K. The conductivity was found to increase with temperature, similar to the case in semiconductors. Analyzing the experimental data with three models, namely the charge-energy-limited-tunneling model, Kivelson model and the three-dimensional variable range hopping (3D-VRH) model demonstrated that these models all describe well the charge transport behaviors of PAn co-doped with SSA and DBSA within the mentioned temperature range. From calculation with the 3D-VRH model, the hopping distance of the conducting PAn is obviously larger than its localization length. The PAn doped with SSA and DBSA enjoys desirable crystallinity due to the co-doping of two functional sulfonic acids. The macroscopic conductivity may correspond to three-dimensional transport in the network of the bundles, and the metallic islands may be attributed to quasi-one-dimensional bundles.

  14. On the Formation of Benzoic Acid and Higher Order Benzene Carboxylic Acids in Interstellar Model Ices grains

    Science.gov (United States)

    McMurtry, Brandon M.; Saito, Sean E. J.; Turner, Andrew M.; Chakravarty, Harish K.; Kaiser, Ralf I.

    2016-11-01

    With a binary ice mixture of benzene (C6H6) and carbon dioxide (CO2) at 10 K under contamination-free ultrahigh vacuum conditions, the formation of benzene carboxylic acids in interstellar ice grains was studied. Fourier transform infrared spectroscopy was used to probe for the formation of new species during the chemical processing of the ice mixture and during the following temperature-programmed desorption. Newly formed benzene carboxylic acid species, i.e., benzoic acid, as well as meta- and para-benzene dicarboxylic acid, were assigned using newly emerging bands in the infrared spectrum; a reaction mechanism, along with rate constants, was proposed utilizing the kinetic fitting of the coupled differential equations.

  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. Sulfonic Acid Modified Hollow Silica Spheres and Its Application in Proton Exchange Membranes

    Institute of Scientific and Technical Information of China (English)

    ZHU Min; YUAN Junjie; ZHOU Guangbin

    2011-01-01

    In order to improve the proton conductivity of hollow silica spheres (HSS)/perfluorosulfonic acid ion-exchange (PFSA) composite membranes as proton exchange membrane,sulfonic acid groups were grafted onto the surfaces of HSS via post grafting methods.TEM images and FT-IR spectra of the obtained sulfonic acid groups modified hollow silica spheres (SAMHSS) illustrated that the sulfonic acid groups were successfully grafted onto the surfaces of HSS.Water uptake and swelling degree of SAMHSS/PFSA composite membranes were found much higher than those of HSS/PFSA membranes due to the introduction of hydrophilic sulfonic acid groups.In a range from 50 ℃C to 130 ℃,the highest conductivity of composite membranes was obtained when 5 wt% SAMHSS was loaded.The maximum conductivity reached 7.5×10-2S·cm-1 at 100 ℃C and 100% relative humidity,even the temperature increased to 130 ℃,the conductivity of composite membranes with 5 wt% SAMHSS could reach 3.7× 10-2 S·cm-1 at 100 % relative humidity,while the conductivity of the recast PFSA was only 2.2x 10-3 S·cm-1.

  17. 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.

  18. 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.

  19. Bifunctional phenyl monophosphonic/sulfonic acid ion exchange resin and process for using the same

    Science.gov (United States)

    Alexandratos, Spiro; Shelley, Christopher A.; Horwitz, E. Philip; Chiarizia, Renato; Gula, Michael J.; Xue, Sui; Harvey, James T.

    2002-01-01

    A cross-linked water-insoluble ion exchange resin comprised of polymerized monomers having a phenyl ring is disclosed. A contemplated resin contains (i) polymerized phenyl ring-containing monomers having a phosphonic acid ligand linked to the phenyl ring, (ii) about 2 to about 5 millimoles per gram (mmol/g) of phosphorus as phosphonic acid ligands, and (iii) a sufficient amount of a sulfonic acid ligand such that the ratio of mmol/g of phosphonic acid to mmol/g sulfonic acid is up to 3:1. A process for removing polyvalent metal cations from aqueous solution, and a process for removing iron(III) cations from acidic copper(II) cation-containing solutions that utilize the contemplated resin or other resins are disclosed.

  20. Synthesis, growth, spectral, and thermal studies of a new organic molecular charge transfer complex crystal: 3-nitroaniline 4-methyl benzene sulfonate.

    Science.gov (United States)

    Selvakumar, E; Anandha babu, G; Ramasamy, P; Chandramohan, A

    2014-03-25

    A new organic intermolecular charge transfer complex 3-nitroaniline 4-methyl benzene sulfonate (NATS) has been successfully synthesized and good optical quality single crystals grown by slow solvent evaporation solution growth technique at room temperature using methanol as the solvent. The (1)H and (13)C NMR spectra were recorded to establish the molecular structure of the title complex. The crystal structure of NATS has been determined by single crystal XRD analysis and it belongs to orthorhombic crystal system with space group Pbca. Fourier transform infrared (FT-IR) spectral study has been carried out to confirm the presence of various functional groups present in the complex. Electronic absorption spectrum was recorded to find the prevalent charge transfer activity in the complex. The UV-Vis-NIR transmission spectrum was recorded in the range 200-2500 nm, to find the optical transmittance window and lower cut off wavelength of the title crystal. The thermal stability of the title complex crystal was studied by using thermo-gravimetric and differential thermal analyses and found that the compound is stable up to 215 °C.

  1. Effects of sodium dodecyl benzene sulfonate on the crystal structures and photocatalytic performance of ZnO powders prepared by hydrothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Limin; Dong, Shuying; Li, Qilu; Li, Yifan; Pi, Yunqing; Liu, Menglin; Han, Xiao; Sun, Jianhui, E-mail: sunjh@htu.cn

    2015-11-15

    A facile and efficient route for the controllable synthesis of ZnO nanostructures by hydrothermal method using sodium dodecyl benzene sulfonate (SDBS) as surfactant was reported. The obtained products were well characterized with the aid of various techniques to probe their crystallographic, morphological, chemical, electrochemical and optical properties. The prepared products were used as photocatalysts in the application of the degradation of metronidazole (MNZ)-contained wastewater under visible light irradiation. A 4.5-fold augmentation of degradation efficiency was in turn observed for optimal ZnO (ZO-0.75) photocatalyst compared with that of sample without SDBS addition (ZO) under the visible light irradiation. The effects of SDBS dosage on the crystal structures of prepared samples as well as the crystal growth mechanism were also probed. - Graphical abstract: ZnO photocatalysts were fabricated through a facile and efficient hydrothermal method using SDBS as structure-directing surfactant in a controllable manner. In particular, the sample with different SDBS dosage exhibited distinct crystal structure and photocatalytic performance. - Highlights: • A rod-like ZnO photocatalyst was facilely synthesized by using SDBS as surfactant. • The effect of SDBS dosage on the crystal structure of photocatalyst was probed. • The probably crystal growth mechanism of prepared photocatalyst was explored. • The optimal ZnO with 0.75 g SDBS dosage displayed the best photocatalytic activity.

  2. Absorption characteristic of paeoniflorin-6'-O-benzene sulfonate (CP-25) in in situ single-pass intestinal perfusion in rats.

    Science.gov (United States)

    Yang, Xiao-Dan; Wang, Chun; Zhou, Peng; Yu, Jun; Asenso, James; Ma, Yong; Wei, Wei

    2016-09-01

    1. Paeoniflorin-6'-O-benzene sulfonate (CP-25) was synthesized to improve the poor oral absorption of paeoniflorin (Pae). 2. This study was performed to investigate the absorptive behavior and mechanism of CP-25 in in situ single-pass intestinal perfusion in rats, using Pae as a control. 3. The results showed that intestinal absorption of CP-25 was neither segmental nor sex dependent. However, the main segment of intestine that absorbed Pae was the duodenum. Furthermore, passive transport was confirmed to be the main absorption pattern of CP-25. More importantly, the absorption of CP-25 was much higher than Pae in the small intestine. 4. Among the ABC transporter inhibitors, the absorption rate of Pae increased in the presence of P-gp inhibitors verapamil and GF120918, which indicated that Pae was a substrate of P-glycoprotein (P-gp), however, such was not observed in the presence of breast cancer resistance protein and multidrug resistance-associated protein 2. Finally, the ABC transporter inhibitors did not have any significant impact on CP-25 as demonstrated in the parallel studies. 5. CP-25 could improve the poor absorption of Pae, which may be attributed to both the lipid solubility enhancement and its resistance to P-gp-mediated efflux.

  3. Electrochemical characteristics of dodecylbenzene sulfonic acid-doped polyaniline in aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Choi, B.Y. [Korea Electr. Power Res. Inst., Taejon (Korea, Republic of). Power Utilization Group; Chung, I.J. [Department of Chemical Engineering, Korea Advanced Institute of Science and Technology, 373-1 Kusong Yusong, Taejon 305-701 (Korea, Republic of); Chun, J.H.; Ko, J.M. [Department of Industrial Chemistry, Taejon National University of Technology, 305-3, Samsung-2 dong, Dong-gu, Taejon 300-717 (Korea, Republic of)

    1999-02-26

    The electrochemical characteristics of the polyaniline (PAn) films doped with dodecylbenzene sulfonic acid (DBSA) were investigated in aqueous solutions by means of cyclic voltammetry. The PAn-DBSAs film showed a good electrochemical activity in a weak acid solution as well as in a strong acid solution due to the incorporation of small cation instead of DBSA trapped in the film for charge neutralization of polymer matrix. (orig.) 39 refs.

  4. Determination of polyfluoroalkyl phosphoric acid diesters, perfluoroalkyl phosphonic acids, perfluoroalkyl phosphinic acids, perfluoroalkyl carboxylic acids, and perfluoroalkane sulfonic acids in lake trout from the Great Lakes region.

    Science.gov (United States)

    Guo, Rui; Reiner, Eric J; Bhavsar, Satyendra P; Helm, Paul A; Mabury, Scott A; Braekevelt, Eric; Tittlemier, Sheryl A

    2012-11-01

    A comprehensive method to extract perfluoroalkyl carboxylic acids, perfluoroalkane sulfonic acids, perfluoroalkyl phosphonic acids, perfluoroalkyl phosphinic acids, and polyfluoroalkyl phosphoric acid diesters simultaneously from fish samples has been developed. The recoveries of target compounds ranged from 78 % to 121 %. The new method was used to analyze lake trout (Salvelinus namaycush) from the Great Lakes region. The results showed that the total perfluoroalkane sulfonate concentrations ranged from 0.1 to 145 ng/g (wet weight) with perfluorooctane sulfonate (PFOS) as the dominant contaminant. Concentrations in fish between lakes were in the order of Lakes Ontario ≈ Erie > Huron > Superior ≈ Nipigon. The total perfluoroalkyl carboxylic acid concentrations ranged from 0.2 to 18.2 ng/g wet weight. The aggregate mean perfluorooctanoic acid (PFOA) concentration in fish across all lakes was 0.045 ± 0.023 ng/g. Mean concentrations of PFOA were not significantly different (p > 0.1) among the five lakes. Perfluoroalkyl phosphinic acids were detected in lake trout from Lake Ontario, Lake Erie, and Lake Huron with concentration ranging from non-detect (ND) to 0.032 ng/g. Polyfluoroalkyl phosphoric acid diesters were detected only in lake trout from Lake Huron, at levels similar to perfluorooctanoic acid.

  5. Direct esterification of olive-pomace oil using mesoporous silica supported sulfonic acids

    Directory of Open Access Journals (Sweden)

    F. Alrouh

    2017-02-01

    Full Text Available Mesoporous silica MCM-41 and SBA-15 containing propyl sulfonic acid groups were synthesized according to the literature and were characterized by X-ray diffraction, N2 adsorption and the H+ exchange capacities of the sulfonic acid groups were titrated. The esterification reaction of glycerol with olive-pomace oil has been carried out by using prepared functionalized mesoporous silica (MCM-41 and SBA-15 as catalysts. It has been monitored by GC two fatty acids (palmitic and oleic acids as reactants in olive-pomace oil and their related monoacylglycerols (Glycerol monopalmitate GMP and monooleate GMO as reaction product. The catalytic activities of the functionalized mesoporous silica were compared with commercial catalysts, these included homogeneous catalysts (p-toluenesulfonic acid and heterogeneous catalysts (Amberlyst-15. The total yield of monoacylglycerols (GMO + GMP was nearly 40%. Remarkably, we found that MCM-41-SO3H was recycled at least 3 times without any loss of activity.

  6. 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.

  7. 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.

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

    Science.gov (United States)

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

    2002-06-01

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

  9. Sulfonated poly(2,5-benzimidazole) (SABPBI) impregnated with phosphoric acid as proton conducting membranes for polymer electrolyte fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Asensio, J.A. [Institut de Ciencia de Materials de Barcelona, Bellaterra (Spain); Universitat Ramon Llull, Barcelona (Spain). Inst. Quimic de Sarria; Borros, S. [Universitat Ramon Llull, Barcelona (Spain). Inst. Quimic de Sarria; Gomez-Romero, P. [Institut de Ciencia de Materials de Barcelona, Bellaterra (Spain)

    2004-10-01

    Previously cast ABPBI membranes were sulfonated by doping with sulfuric acid followed by heat treatment at 450 {sup o}C for 5 min in air. Sulfonation degrees between 35 and 49% of the benzimidazole rings were achieved. The resulting SABPBI membranes were impregnated with phosphoric acid (H{sub 3}PO{sub 4} 85%/H{sub 2}O, 70:30 bath). For concentrated phosphoric acid baths (above 65%), the capacity of these membranes for phosphoric acid uptake (and consequently also their conductivity) increased with the degree of sulfonation. Sulfonated and acid doped SABPBI membranes were characterized in terms of degree of sulfonation, thermal stability (TGA), X-ray diffraction, FTIR spectroscopy and proton conductivity in the dry state, and compared with phosphoric acid impregnated ABPBI studied earlier. The maximum conductivity measured in dry conditions was 3.5x10{sup -2} S cm{sup -2} at 185 {sup o}C for SABPBI 4.6H{sub 3}PO{sub 4} (with a degree of sulfonation of 41%) which compares favorably with non-sulfonated ABPBI and makes feasible their application in PEM Fuel Cells working at temperatures of 150-200 {sup o}C. (Author)

  10. Esterification free fatty acid in palm fatty acid distillate using sulfonated rice husk ash catalyst

    Science.gov (United States)

    Hidayat, Arif; Sutrisno, Bachrun

    2017-01-01

    Indonesia, as one of the biggest palm oil producers and exporters in the world, is producing large amounts of low-grade oil such as Palm Fatty Acid Distillate (PFAD) from palm oil industries. The use of PFAD can reduce the cost of biodiesel production significantly, which makes PFAD a highly potential alternative feedstock for biodiesel production. In this paper, the esterification of free fatty acid (FFA) on PFAD was studied using rice husk ash (RHA) as heterogeneous catalyst. The rice husk ash catalyst was synthesized by sulfonation using concentrated sulfuric acid. The RHA catalyst were characterized by using different techniques, such as porosity analysis, Fourier transform infrared (FT-IR) spectroscopy, total number of acid sites and elemental analysis. The effects of the molar ratio of methanol to PFAD (1-10%), the molar ratio of methanol to PFAD (4:1-10:1), and the reaction temperature (40-60°C) were studied for the conversion of FFA to optimize the reaction conditions. The results showed that the optimal conditions were an methanol to PFAD molar ratio of 10:1, the catalyst amount of 10 wt% of PFAD, and reaction temperature of 60°C.

  11. Analytical method for determination of benzene-arsenic acids

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, G.L.; Bayse, G.S.

    1988-01-01

    A sensitive analytical method has been modified for use in determination of several benzenearsonic acids, including arsanilic acid (p-aminobenzenearsonic acid), Roxarsone (3-nitro-4-hydroxybenzenearsonic acid), and p-ureidobenzene arsonic acid. Controlled acid hydrolysis of these compounds produces a quantitative yield of arsenate, which is measured colorimetrically as the molybdenum blue complex at 865 nm. The method obeys Beer's Law over the micromolar concentration range. These benzenearsonic acids are routinely used as feed additives in poultry and swine. This method should be useful in assessing tissue levels of the arsenicals in appropriate extracts.

  12. 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.

  13. 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.

  14. 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%).

  15. 4-[(E-(5-tert-Butyl-2-hydroxyphenyldiazenyl]benzoic acid benzene hemisolvate

    Directory of Open Access Journals (Sweden)

    Edward R. T. Tiekink

    2010-03-01

    Full Text Available The title benzene hemisolvate, C17H18N2O3·0.5C6H6, features an essentially planar (the r.m.s. deviation of the non-H atoms, excluding methyl-C, is 0.071 Å diazo molecule with an E conformation about the N=N bond, and a half-molecule of benzene disposed about a centre of inversion. The dihedral angle formed between the benzene rings of the diazo molecule is 7.69 (12°. In the crystal, centrosymmetrically related dimers associate via the eight-membered carboxylic acid dimer synthon, {...HOC(=O}2, and these are connected into a supramolecular chain along the b axis via C—H...O contacts.

  16. 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.

  17. 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.

  18. Lubricating oil compositions containing overbased calcium sulfonates and metal salts of alkyl catechol dithiophosphoric acid

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, E.S.; Cerrito, E.; Liston, T.V.

    1987-05-26

    This patent describes a lubricating oil composition containing an overbased calcium hydrocarbyl sulfonate. The improvement wherein the lubricating oil composition additionally comprises an effective amount to reduce wear of a metal salt of an alkyl catechol dithiophosphoric acid ester of the formula: wherein R is alkyl containing 10 to 18 carbon atoms, or mixtures thereof, M is an alkali or alkaline earth metal or transition metal and n corresponds to the valence of the metal M.

  19. 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.

  20. 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.

  1. Precision Morphology in Sulfonic, Phosphonic, Boronic, and Carboxylic Acid Polyolefins

    Science.gov (United States)

    2013-11-15

    Science Part A: Polymer Chemistry , (02 2011): 0. doi: 10.1002/pola.24491 Number of Papers published in peer-reviewed journals: (b) Papers published in...Wagener. Effects of Boron-Containing Lewis Acids on Olefin Metathesis, Organometallics , (05 2013): 0. doi: 10.1021/om400257b Michael D. Schulz, Rachel R...Ford, Kenneth B. Wagener. Insertion metathesis depolymerization, Polymer Chemistry , (05 2013): 0. doi: 10.1039/c3py00531c Pascale Atallah, Kenneth

  2. Vacuum thermal evaporation of polyaniline doped with camphor sulfonic acid

    Energy Technology Data Exchange (ETDEWEB)

    Boyne, Devon; Menegazzo, Nicola; Pupillo, Rachel C.; Rosenthal, Joel; Booksh, Karl S., E-mail: kbooksh@udel.edu [Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716 (United States)

    2015-05-15

    Intrinsically conducting polymers belong to a class of organic polymers with intriguing electronic and physical properties specifically for electro-optical applications. Significant interest into doped polyaniline (PAni) can be attributed to its high conductivity and environmental stability. Poor dissolution in most solvents has thus far hindered the successful integration of PAni into commercial applications, which in turn, has led to the investigations of various deposition and acidic doping methods. Physical vapor deposition methods, including D.C. magnetron sputtering and vacuum thermal evaporation, have shown exceptional control over physical film properties (thickness and morphology). However, resulting films are less conductive than films deposited by conventional methods (i.e., spin and drop casting) due to interruption of the hyperconjugation of polymer chains. Specifically, vacuum thermal evaporation requires a postdoping process, which results in incorporation of impurities and oxidation of surface moieties. In this contribution, thermally evaporated films, sequentially doped by vacuum evaporation of an organic acid (camphorsulfonic acid, CSA) is explored. Spectroscopic evidence confirms the successful doping of PAni with CSA while physical characterization (atomic force microscopy) suggests films retain good morphology and are not damaged by the doping process. The procedure presented herein also combines other postpreparation methods in an attempt to improve conductivity and/or substrate adhesion.

  3. Preparation of sulfonic acid-containing rubbers from natural rubber vulcanizates

    Science.gov (United States)

    Poonsawat, Worapong; Poompradub, Sirilux; Ngamcharussrivichai, Chawalit

    2014-06-01

    In this work, a series of sulfonic acid-containing rubbers were prepared by aqueous phase oxidation of natural rubber vulcanizates in the presence of hydrogen peroxide (H2O2) and formic acid (HCOOH). The starting vulcanizates were neatly prepared via an efficient vulcanization (EV) system by varying mass ratio of N-cyclohexyl-2-benzothiazole sulfonamide (CBS), as an accelerator, to sulfur. The oxidation conditions were controlled at the molar ratio of H2O2: HCOOH = 1:1, the concentration of H2O2 = 15 wt.%, the temperature = 50 °C, and the reaction time = 3 h. The rubber materials before and after the oxidation were characterized for their physicochemical properties by using Fourier transform infrared spectroscopy, bomb calorimetry, acid-base titration and swelling measurements. The results indicated the presence of sulfonic acid group in the oxidized rubbers, generated by the oxidative cleaves of sulfide crosslinks in the rubber vulcanizates. The oxidation decreased the sulfur content of the rubber in which the level of sulfur loss was determined by the CBS/sulfur ratio. Moreover, the acidity of the oxidized products was correlated with the amount of sulfur remaining.

  4. Angiogenic Potential of 3-Nitro-4-Hydroxy Benzene Arsonic Acid (Roxarsone)

    OpenAIRE

    2008-01-01

    Background Roxarsone (3-nitro-4-hydroxy benzene arsonic acid) is an arsenic compound widely used in the poultry industry as a feed additive to prevent coccidiosis, stimulate growth, and to improve tissue pigmentation. Little is known about the potential human health effects from roxarsone released into the environment from chicken waste or from residual compound in chicken products. Objective The growth potentiation and enhanced tissue pigmentation suggest that low levels of roxarsone exposur...

  5. 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.

  6. STUDY ON THE EFFECT OF POLYSTYRENE SULFONIC ACID MACROMOLECULES ON THE POLYMERIZATION OF ACRYLAMIDE

    Institute of Scientific and Technical Information of China (English)

    WANG Shenguo; XI Fu; LI Zhifen

    1983-01-01

    The effect of polystyrene sulfonic acid (PSSA) macromolecules on the polymerization of acrylamide (AM) has been studied. It was found that the rates of polymerization of AM were greatly increased in the presence of PSSA in the polymerization system. The maximum value of the rate of polymerization of AM was obtained when the ratio of[-SO3H]: [AM] reached 3:1. When the insoluble crosslinked PSSA was used instead of the soluble one, this effect decreased considerably. The interaction between molecules of PSSA and AM was determined by infrared spectroscopy, elementary analysis and X-ray photoelectron spectroscopy.The combination form, -SO3-NH3+ CO-, formed between sulfonic group and amide group was found to be existed since the infrared absorption band of -NH2 shifted from 3400 cm-1 to 3150cm-1, the binding energy of electron N1S changed from 399.7 eV to 401.3 eV, and the atomic ratio of N to S of the products was similar to the ratio of reagents. Based on these experimental results, the mechanism of AM polymerization in the presence of PSSA is proposed. The initial step is the combination of AM with sulfonic group to form -CONH3+, then followed by polymerization on the PSSA macromolecule. The role of PSSA on the polymerization of AM is discussed.

  7. The Study on the Role of Intestinal Microecology Protecting Tight Junction Protein Between the Epithelial Cells of Intestinal Mucosal Barrier in Rats with Trinitro-Benzen-Sulfonic Acid Induced Colitis%肠道微生态对三硝基苯磺酸诱导大鼠结肠炎肠黏膜上皮细胞紧密连接蛋白occludin保护作用的研究

    Institute of Scientific and Technical Information of China (English)

    张文远; 姜伟炜

    2010-01-01

    目的 研究肠道微生态对三硝基苯磺酸(trinitro-benze-sulfonic acid,TNBS)诱导大鼠结肠炎肠黏膜上皮细胞紧密连接蛋白的保护作用.方法 建立TNBS诱导大鼠结肠炎模型.实验分为正常组、模型组和双歧杆菌、嗜酸乳杆菌、肠球菌三联活菌(金双歧)组.进行疾病活动指数(DAI)和组织学损伤评分.用ELISA法测定结肠组织TNF-α、IL-10和血清内毒素,采用免疫组织学染色检测紧密连接(tight junction,TJ)相关蛋白occludin的分布.结果 TNBS诱导大鼠结肠炎后,DAI和组织学损伤评分增高,结肠组织TNF-α水平升高,IL-10水平降低和血清内毒素水平升高,而经金双歧处理后,DAI和组织学损伤评分明显下降,结肠组织TNF-α水平降低,IL-10水平升高和血清内毒素水平降低,组间比较差异有显著性(P<0.05).TNBS诱导大鼠结肠炎后,TJ结构遭到破坏,TJ相关蛋白的表达亦减少,而金双歧处理后,可使TNBS引起的TJ结构受损减轻,相关蛋白的表达增多(P<0.05).结论 肠道微生态对TNBS诱导大鼠结肠炎肠黏膜上皮细胞紧密连接蛋白具有明显的保护作用.

  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. Spatially electrodeposited platinum in polyaniline doped with poly(styrene sulfonic acid) for methanol oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Li-Ming; Tang, Wang-Rung; Wen, Ten-Chin [Department of Chemical Engineering, National Cheng Kung University, Tainan 70101 (Taiwan)

    2007-02-10

    Polyaniline (PANI) can be doped with poly(styrene sulfonic acid) (PSS) via doping-dedoping-redoping process. The specific characteristics of PANI doped with PSS (PANI-PSS) were checked by UV-vis spectroscopy, cyclic voltammetry, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). PANI-PSS was found to have spatial structure with minimum degradation products. Platinum can be potentiostatically deposited in a spatial layer of the PANI-PSS as evidenced by electron dispersive element analysis (EDS) and Auger electron spectroscopy (AES). The electrochemical measurements demonstrated that PANI-PSS-Pt exhibited a much higher electrocatalytic activity for methanol oxidation than PANI-Pt. (author)

  10. 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.

  11. 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.

  12. Theoretical stusy of the reaction between 2,2',4' - trihydroxyazobenzene-5-sulfonic acid and zirconium

    Science.gov (United States)

    Fletcher, Mary H.

    1960-01-01

    Zirconium reacts with 2,2',4'-trihydroxyazobenzene-5-sulfonic acid in acid solutions to Form two complexes in which the ratios of dye to zirconium are 1 to 1 and 2 to 1. Both complexes are true chelates, with zirconium acting as a bridge between the two orthohydroxy dye groups. Apparent equilibrium constants for the reactions to form each of the complexes are determined. The reactions are used as a basis for the determination of the active component in the dye and a graphical method for the determination of reagent purity is described. Four absorption spectra covering the wave length region from 350 to 750 mu are given, which completely define the color system associated with the reactions in solutions where the hydrochloric acid concentration ranges from 0.0064N to about 7N.

  13. 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.

  14. Cross-linked polystyrene sulfonic acid and polyethylene glycol as a low-fouling material.

    Science.gov (United States)

    Alghunaim, Abdullah; Zhang Newby, Bi-min

    2016-04-01

    A negatively charged hydrophilic low fouling film was prepared by thermally cross-linking a blend consisting of polystyrene sulfonic acid (PSS) and polyethylene glycol (PEG). The film was found to be stable by dip-washing. The fouling resistance of this material toward bacterial (Escherichia coli) and colloidal (polystyrene particles) attachment, non-specific protein (fibronectin) adsorption and cell (3T3 NIH) adhesion was evaluated and was compared with glass slides modified with polyethylene glycol (PEG) brushes, oxidized 3-mercaptopropyltrimethoxysilane (sulfonic acid, SA), and n-octadecyltrichlorosilane (OTS). The extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory and thermodynamic models based on surface energy were used to explain the interaction behaviors of E. coli/polystyrene particles-substrate and protein-substrate interactions, respectively. The cross-linked PSS-PEG film was found to be slightly better than SA and PEG toward resisting non-specific protein adsorption, and showed comparable low attachment results as those of PEG toward particle, bacterial and NIH-3T3 cells adhesion. The low-fouling performance of PSS-PEG, a cross-linked film by a simple thermal curing process, could allow this material to be used for applications in aqueous environments, where most low fouling hydrophilic polymers, such as PSS or PEG, could not be easily retained.

  15. 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.

  16. Solvent-induced chemical shifts of methoxyl nuclear resonance signals in chalcones by benzene and trifluoroacetic acid

    Science.gov (United States)

    Khurana, Shashi K.; Krishnamoorthy, V.; Parmar, Virinder S.

    The 1H NMR spectra of eight different methoxylated chalcones have separately been recorded, (1) in deuterated chloroform; (2) in a mixture (1:1) of deuterated chloroform and benzene; and (3) in a mixture of deuterated chloroform, benzene and trifluoroacetic acid (2:2:1) and the benzene induced and TFA induced shift values have been assigned to different methoxyl groups. These shift values can serve as a guide in determining the structures of natural or new chalcones. The steric, electronic and conformational factors are discussed to explain the shift values.

  17. Interaction of multi-walled carbon nanotubes with perfluorinated sulfonic acid ionomers and surface treatment studies

    DEFF Research Database (Denmark)

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

    2014-01-01

    efficient, user-friendly and systematic studies based on our earlier experience. In this work, multi-walled carbon nanotubes (MWCNTs) from Showa Denko® and the corresponding acid modified products were explored. The adsorption at low concentration was found to follow a Langmuir isotherm. Adsorption......The interaction between high surface area nano-carbon catalyst supports for proton exchange membrane fuel cells (PEMFCs) and perfluorinated sulfonic acid (Nafion®) ionomer was studied 19 fluorine nuclear magnetic resonance spectroscopy (19F-NMR). The method was developed and improved for more....... The results will contribute to optimize electrode preparation with novel nano-carbon catalyst supports and durable catalyst for low temperature (LT) PEMFCs....

  18. Green Approach to Corrosion Inhibition of Mild Steel by Lignin Sulfonate in Acidic Media

    Institute of Scientific and Technical Information of China (English)

    Muna A.ABU-DALO; Nathir A.F.AL-RAWASHDEH; Ahmed A.MUTLAQ

    2016-01-01

    The inhibition effect of lignin sulfonate against corrosion for mild steel in acidic solution has been examined by means of FTIR (fourier transform infrared spectroscopy),FAA (flame atomic absorption)spectroscopy,SEM (scanning electron microscope),EDS (energy dispersive X-ray spectroscopy),and mass loss techniques.The results revealed that lignin is a beneficial inhibitor for mild steel corrosion in acidic medium.It has been further found that Langmuir adsorption isotherm is obeyed by the tested lignin′s adsorption over the surface of mild steel.The range of inhibition efficiency (IE)in 2 mol·L-1 HCl was found to be 75·88%-87·88% for Reax 88A,40·72%-60·32%for Reax 88B,and 54·32%-63·03% for Reax 100M,after immersed at 298 K for 24 h time.

  19. Synergistic Effects of Petroleum Carboxylate/Alkyl Benzene Sulfonate Compound System and Its Structural Cause%石油羧酸盐与烷基苯磺酸盐的复配效果及其结构成因

    Institute of Scientific and Technical Information of China (English)

    黄宏度; 陈思雅; 秦少华; 吴一慧; 郑为; 陈亮; 陈友猛; 张群

    2016-01-01

    In order to reveal the performance of petroleum carboxylate and alkyl benzene sulfonate compound system,the effect of mixed micelle (supramolecular structure) formed from petroleum carboxylate and alkyl benzene sulfonate on the interfacial activity of compound system was investigated.The research results showed that the difference of hydrophilic lipophilic balance (HLB) value made petroleum carboxylate and alkyl benzene sulfonate having different insertion depth of molecules at oil-water interface.The distance of polar groups became far and polar group' s repulsion reduced.As a result,their mixed micelles arranged more closely,the interracial adsorption increased and the interfacial activity was better than that of a single surfactant.The structural characteristics of compound system made it having the advantages of interfacial activity.Compound system had ultra-low interfacial tension in a wide range of surfactant concentration and salinity.It had an excellent interfacial activity in weak base case (0.6%-1.2% Na2CO3),which avoided formation damage from strong base (NaOH).It took less surfactant to achieve ultra-low interfacial tension and could reduce the cost of surfactants for chemical flooding.After contacting with oil droplet,it could quickly achieve ultra-low interfacial tension,which was beneficial to the oil displacement process.The interfacial activity of compound system was good in strong base,weak base and none-alkali system.The molecular structure of alkyl benzene sulfonate which had a good synergistic effect with petroleum carboxylate should be linear so that they could form closed mixed micelle with a better interfacial activity.%为揭示石油羧酸盐与烷基苯磺酸盐复配体系的性能特征,考察了石油羧酸盐和烷基苯磺酸盐形成的混合胶束(超分子结构)对复配体系界面活性的影响.结果表明,亲水亲油平衡值(HLB值)的差别使石油羧酸盐分子和烷基苯磺酸盐分子在油水界面上插入

  20. CHARACTERIZATION OF SULFONATED SYNDIOTACTIC POLYSTYRENE%磺化间规聚苯乙烯的表征

    Institute of Scientific and Technical Information of China (English)

    王进; 祝方明; 刘金成; 黎华明; 林尚安

    2001-01-01

    The effect of different sulfonation degree on properties of sulfonated syndiotactic polystyrene(SsPS) was investigated by 1H-NMR,13C-NMR,FTIR,DSC and WAXD.The results of 13C-NMR showed that a peak at δ=145.5 appeared in all SsPS spectra,which proved that the syndiotactic structure of syndiotactic polystyrene(sPS) still existed in SsPS.With increasing degree of sulfonition,the chemical shifts of C-1 and C\\|3 for sulfonated benzene ring turned out to be wider.1H-NMR spectra showed that C\\|3 for sulfonated benzene ring had a chemical shift of 7.66.FTIR spectra showed that sulfonic acid groups were introduced on the para position of benzene rings and with increasing sulfonation degree,the absorption strength of 612/1600 cm-1,834/1600cm-1 increased,but the absorption strength of 1078/1600cm-1 decreased.The absorption of ~1030cm-1,~1179cm-1,~1217cm-1 appeared when the sulfonation degree was higher that 6%.sPS and SsPS-H-2.2 had absorption at 975 and 943cm-1 and also had double peaks around ~1175cm-1;DSC showed that with increasing sulfonation degree, the glass transition temperature increased, the melt temperature,crystallization temperature and crystallization degree decreased;SsPS couldn't crystallize when sulfonation degree was higher that 6mol%;WAXD proved that sPS had the α and β crystal types, however,SsPS with 2.2% sulfonation degree only had the β crystal type, and SsPS with 6.1% sulfonation degree didn't crystallize.

  1. Direct Synthesis of Phenol from Benzene on an Activated Carbon Catalyst Treated with Nitric Acid

    Institute of Scientific and Technical Information of China (English)

    Cui-hong Chen; Jia-quan Xu; Ming-ming Jin; Gui-ying Li; Chang-wei Hu

    2011-01-01

    Commercially available coal-based activated carbon was treated by nitric acid with different concentrations and the resultant samples were used as catalysts for the direct hydroxylation of benzene to phenol in acetonitrile. Boehm titration, X-ray photoelectron spectroscopy,scanning electron microscope coupled with an energy dispersive X-ray microanalyzer, and Brunauer-Emmett-Teller method were used to characterize toe samples. The number of carboxyl groups on the surface was found to be the main factor affecting the catalytic activity. An optimum catalytic performance with a yield of 15.7% and a selectivity of 87.2% to phenol was obtained.

  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. 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.

  4. A Durable Catalyst for Vapor Phase Nitration of Benzene with Nitric Acid

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Experimental results in this work demonstrate that PW12-H2SO4/SiO2 catalyst is a good and durable catalyst for vapor phase nitration of benzene to nitrobenzene (NB) using 65% nitric acid at normal pressure. It retains the advantages of using H2SO4 as catalyst and the addition of phosphotungstic acid holds back the effusion of sulfuric acid. This new catalyst keeps high activity (the conversion of HNO3 is more than 92%), high selectivity of NB (more than 97%) and high space time yield (STY 1.5 kg NB/kg cat.h) even after 150 h on stream, under condition of 423 K, SV=3200 ml/g h.

  5. Removal of 5-Amino-2-chlorotoluene-4-sulfonic and Chlorhydric Acids From Wastewater by Weakly Basic Resin: Equilibrium and Kinetics

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    To study the adsorption of 5-Amino-2-chlorotoluene-4-sulfonic (CLT) and chlorhydric (HCl) acids from wastewater by weakly basic resin.Methods The kinetics and isotherm were studied. Thermodynamic parameters for the adsorption of acids were calculated and discussed.Results The adsorption of CLT and HCl acids followed Langmuir isotherm and the first-order kinetics model.Conclusion The adsorptive affinity of the two acids on D301R is in the order of CLT acid > HCl acid. CLT and HCl acids can be separated.

  6. Mineralization of sulfonated azo dyes and sulfanilic acid by Phanerochaete chrysosporium and Streptomyces chromofuscus.

    Science.gov (United States)

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

    1992-11-01

    Five 14C-radiolabeled azo dyes and sulfanilic acid were synthesized and used to examine the relationship between dye substitution patterns and biodegradability (mineralization to CO2) by a white-rot fungus and an actinomycete. 4-Amino-[U-14C]benzenesulfonic acid and 4-(3-sulfo-4-aminophenylazo)-[U-14C]benzenesulfonic acid were used as representative compounds having sulfo groups or both sulfo and azo groups. Such compounds are not known to be present in the biosphere as natural products. The introduction of lignin-like fragments into the molecules of 4-amino-[U-14C]benzenesulfonic acid and 4-(3-sulfo-4-aminophenylazo)-[U-14C]benzenesulfonic acid by coupling reactions with guaiacol (2-methoxyphenol) resulted in the formation of the dyes 4-(3-methoxy-4-hydroxyphenylazo)-[U-14C]benzenesulfonic acid and 4-(2-sulfo-3'-methoxy-4'-hydroxy-azobenzene-4-azo)-[U-14C]benzenesulf oni c acid, respectively. The synthesis of acid azo dyes 4-(2-hydroxy-1-naphthylazo)-[U-14C]benzenesulfonic acid and 4-(4-hydroxy-1-naphthylazo)-[U-14C]benzenesulfonic acid also allowed the abilities of these microorganisms to mineralize these commercially important compounds to be evaluated. Phanerochaete chrysosporium mineralized all of the sulfonated azo dyes, and the substitution pattern did not significantly influence the susceptibility of the dyes to degradation. In contrast, Streptomyces chromofuscus was unable to mineralize aromatics with sulfo groups and both sulfo and azo groups. However, it mediated the mineralization of modified dyes containing lignin-like substitution patterns. This work showed that lignocellulolytic fungi and bacteria can be used for the biodegradation of anionic azo dyes, which thus far have been considered among the xenobiotic compounds most resistant to biodegradation.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Analysis of metolachlor ethane sulfonic acid chirality in groundwater: A tool for dating groundwater movement in agricultural settings

    Science.gov (United States)

    Chemical chirality of pesticides can be a useful tool for studying environmental processes. The chiral forms of metolachlor ethane sulfonic acid (MESA), an abundant metabolite of metolachlor, and metolachlor were examined over a 6 year period in groundwater and a groundwater-fed stream in a riparia...

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. Flexible, all-organic ammonia sensor based on dodecylbenzene sulfonic acid-doped polyaniline films

    Energy Technology Data Exchange (ETDEWEB)

    Rizzo, G. [Dipartimento di Chimica Industriale e Ingegneria dei Materiali, Universita degli Studi di Messina (Italy); Arena, A.; Donato, N.; Latino, M.; Saitta, G. [Dipartimento di Fisica della Materia e Ingegneria Elettronica, Universita degli Studi di Messina (Italy); Bonavita, A. [Dipartimento di Chimica Industriale e Ingegneria dei Materiali, Universita degli Studi di Messina (Italy); Neri, G., E-mail: neri@ingegneria.unime.i [Dipartimento di Chimica Industriale e Ingegneria dei Materiali, Universita degli Studi di Messina (Italy)

    2010-09-30

    A stable chlorobenzene dispersion of conducting polyaniline (PANI) has been obtained by doping emeraldine base with dodecylbenzene sulfonic acid (DBSA) and studied by spectrophotometric measurements in the UV-vis-IR range. The electrical properties of PANI: DBSA films obtained from the above dispersion have been investigated under different temperature and relative humidity conditions. All-organic chemoresistive devices have been developed by spin-coating the PANI: DBSA dispersion on flexible substrates, and then by depositing electrodes on the top, from a carbon nanotube conducting ink. Sensing tests performed under exposition to calibrated amounts of ammonia reveal that these simple and inexpensive sensors are able to detect ammonia at room temperature in a reliable way, with a sensitivity linearly related to concentration in the range between 5 ppm and 70 ppm.

  13. 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.

  14. Assessment of perfluorooctanoic acid and perfluorooctane sulfonate in surface water - Tamil Nadu, India.

    Science.gov (United States)

    Sunantha, Ganesan; Vasudevan, Namasivayam

    2016-08-15

    As an emerging class of environmentally persistent organic pollutants, perfluorinated compounds (PFCs), particularly perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS); have been universally found in the environment. Wastewater and untreated effluents are likely the major causes for the accumulation of PFCs in surface water. There are very few reports on the contamination of PFCs in the developing countries, particularly in India. This study reports the quantitative analysis of PFOA and PFOS in Noyyal, Cauvery, and also lakes in and around Chennai, using Ultra-Fast liquid chromatograph. The concentration of PFOA and PFOS ranged from 4 to 93ng/L and 3 to 29ng/L, respectively. The concentration of PFOS was below detectable limit in Cauvery River. A reliable concentration of PFOA was recorded at all sites of River Cauvery (5ng/L). The present study could be useful for the assessment of future monitoring programs of PFOA and PFOS in the surface water.

  15. 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.

  16. 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

  17. 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.

  18. Isonicotinic acid-ligated cobalt (II phthalocyanine-modified titania as photocatalyst for benzene degradation via fluorescent lamp

    Directory of Open Access Journals (Sweden)

    Joey Andrew A. Valinton

    2016-06-01

    Full Text Available The utilization of bis(isonicotinic acidphthalocyaninatocobalt (II [CoPc(isa2] incorporated on TiO2 has been studied as a photocatalyst to degrade benzene vapor under fluorescent lamp (indoor light conditions. The photocatalytic activity of [CoPc(isa2]-TiO2 compared to TiO2 showed an increase in the extent of degradation. The axial isonicotinic acid ligand attached to CoPc improved the degradation rate of benzene as compared with unligated CoPc-TiO2 which may be attributed to the enhancement of electronic structure in the complex due to the additional isonicotinic acid ligand and its possible attachment to the TiO2 surface through the carboxylic acid moiety. Therefore, covalently-linked CoPc(isa2 to TiO2 can enhance the extent of photodegradation of benzene and other common volatile organic compounds under indoor lighting conditions.

  19. Primary biodegradation of linear alkyltoluene and alkylbenzene sulfonates.

    Science.gov (United States)

    Singh, M; Satish, S

    1989-01-01

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

  20. Thermodynamics of the ethylene glycol pair interaction with some amino acids and benzene

    Energy Technology Data Exchange (ETDEWEB)

    Kustov, Andrey V., E-mail: kustov@isuct.ru [G.A. Krestov Institute of Solution Chemistry, Russian Academy of Sciences, 1 Akademicheskaya Str., 153045 Ivanovo (Russian Federation); Ivanovo State University of Chemistry and Technology, Sheremetevskiy av. 7, 153012, Ivanovo (Russian Federation); Antonova, Olga A.; Smirnova, Nataliya L. [G.A. Krestov Institute of Solution Chemistry, Russian Academy of Sciences, 1 Akademicheskaya Str., 153045 Ivanovo (Russian Federation); Ivanovo State University of Chemistry and Technology, Sheremetevskiy av. 7, 153012, Ivanovo (Russian Federation)

    2014-06-01

    Highlights: • Thermodynamics of amino acid solutions in highly aqueous Eg was studied at 298 and 313 K. • The pair interaction parameters were computed using the virial expansion technique. • The results were discussed in terms of solute–Eg pair interactions. - Abstract: We have studied thermodynamics of interaction of benzene and some amino acids with ethylene glycol (Eg) which is a stabilizing agent for proteins in water using calorimetric and solubility data. Enthalpic, entropic and free energy parameters in highly diluted aqueous solutions have been computed at 298 and 313 K using the virial expansion technique and compared with available literature values. The results obtained are discussed in terms of solute–solute interactions and their relation to stability of macromolecules.

  1. Toxicokinetics of seven perfluoroalkyl sulfonic and carboxylic acids in pigs fed a contaminated diet.

    Science.gov (United States)

    Numata, Jorge; Kowalczyk, Janine; Adolphs, Julian; Ehlers, Susan; Schafft, Helmut; Fuerst, Peter; Müller-Graf, Christine; Lahrssen-Wiederholt, Monika; Greiner, Matthias

    2014-07-16

    The transfer of a mixture of perfluoroalkyl acids (PFAAs) from contaminated feed into the edible tissues of 24 fattening pigs was investigated. Four perfluoroalkyl sulfonic (PFSAs) and three perfluoroalkyl carboxylic acids (PFCAs) were quantifiable in feed, plasma, edible tissues, and urine. As percentages of unexcreted PFAA, the substances accumulated in plasma (up to 51%), fat, and muscle tissues (collectively, meat 40-49%), liver (under 7%), and kidney (under 2%) for most substances. An exception was perfluorooctanesulfonic acid (PFOS), with lower affinity for plasma (23%) and higher for liver (35%). A toxicokinetic model is developed to quantify the absorption, distribution, and excretion of PFAAs and to calculate elimination half-lives. Perfluorohexanoic acid (PFHxA), a PFCA, had the shortest half-life at 4.1 days. PFSAs are eliminated more slowly (e.g., half-life of 634 days for PFOS). PFAAs in pigs exhibit longer elimination half-lives than in most organisms reported in the literature, but still shorter than in humans.

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

    Science.gov (United States)

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

    2013-10-15

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

  3. An Introduction to Multivariate Curve Resolution-Alternating Least Squares: Spectrophotometric Study of the Acid-Base Equilibria of 8-Hydroxyquinoline-5-Sulfonic Acid

    Science.gov (United States)

    Rodriguez-Rodriguez, Cristina; Amigo, Jose Manuel; Coello, Jordi; Maspoch, Santiago

    2007-01-01

    A spectrophotometric study of the acid-base equilibria of 8-hydroxyquinoline-5-sulfonic acid to describe the multivariate curve resolution-alternating least squares algorithm (MCR-ALS) is described. The algorithm provides a lot of information and hence is of great importance for the chemometrics research.

  4. Sulfonated reduced graphene oxide as a highly efficient catalyst for direct amidation of carboxylic acids with amines using ultrasonic irradiation.

    Science.gov (United States)

    Mirza-Aghayan, Maryam; Tavana, Mahdieh Molaee; Boukherroub, Rabah

    2016-03-01

    Sulfonated reduced graphene oxide nanosheets (rGO-SO3H) were prepared by grafting sulfonic acid-containing aryl radicals onto chemically reduced graphene oxide (rGO) under sonochemical conditions. rGO-SO3H catalyst was characterized by Fourier-transform infrared (FT-IR) spectroscopy, Raman spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray photoelectron spectroscopy (XPS). rGO-SO3H catalyst was successfully applied as a reusable solid acid catalyst for the direct amidation of carboxylic acids with amines into the corresponding amides under ultrasonic irradiation. The direct sonochemical amidation of carboxylic acid takes place under mild conditions affording in good to high yields (56-95%) the corresponding amides in short reaction times.

  5. Poly(vinylbenzyl sulfonic acid)-grafted poly(ether ether ketone) membranes

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Mi-Lim; Choi, Jisun; Woo, Hyun-Su; Kumar, Vinod; Sohn, Joon-Yong; Shin, Junhwa, E-mail: shinj@kaeri.re.kr

    2014-02-15

    Highlights: • PEEK-g-PVBSA, a polymer electrolyte membrane was prepared by a radiation grafting technique. • Poly(ether ether ketone) (PEEK), an aromatic hydrocarbon polymer was used as a grafting backbone film. • The water uptake, proton conductivity, and methanol permeability of the membranes were evaluated. • PEEK-g-PVBSA membranes show considerably lower methanol permeability compared to a Nafion membrane. -- Abstract: In this study, an aromatic hydrocarbon based polymer electrolyte membrane, poly(vinylbenzyl sulfonic acid)-grafted poly(ether ether ketone) (PEEK-g-PVBSA), has been prepared by the simultaneous irradiation grafting of vinylbenzyl chloride (VBC) monomer onto a PEEK film and subsequent sulfonation. Each chemical conversion was monitored by FT-IR and SEM–EDX instruments. The physicochemical properties including IEC, water uptake, proton conductivity, and methanol permeability of the prepared membranes were also investigated and found that the values of these properties increase with the increase of degree of grafting. It was observed that the IEC values of the prepared PEEK-g-PVBSA membranes with 32%, 58%, and 80% DOG values were 0.50, 1.05, and 1.22 meq/g while the water uptakes were 14%, 20%, and 21%, respectively. The proton conductivities (0.0272–0.0721 S/cm at 70 °C) were found to be somewhat lower than Nafion 212 (0.126 S/cm at 70 °C) at a relative humidity of 90%. However, the prepared membranes showed a considerably lower methanol permeability (0.61–1.92 × 10{sup −7} cm{sup 2}/s) compared to a Nafion 212 membrane (5.37 × 10{sup −7} cm{sup 2}/s)

  6. Effect of magnetic field on property and structure of polyaniline doped with multiple sulfonic acids

    Institute of Scientific and Technical Information of China (English)

    MA Li; HUANG Ke-long; CHEN Chao; GAN Meng-yu; LU Wei; CHEN Feng-qiang

    2008-01-01

    Polyaniline(PAn) doped with multiple sulfonic acid system of dodecylbenzenesulfonic acid(DBSA) and sulfosalicylic acid(SSA) was synthesized by emulsion polymerization using ammonium persulfate(APS) as an oxidizing agent in the presence and the absence of a constant magnetic field(MF)of 0.8 T. The structure and properties of the PAn were characterized by X-ray diffractometer(XRD), thermogravimetric apparatus(TGA), FT-IR spectroscope(FT-IR) and four probe digital multimeter. The results indicate that, when the molar ratio of DBSA to SSA is 1/3, that of dopant to An is 3/2, that of APS to An is 4/5 in the synthesizing media, and the doping time is 3 h, the conductivity of the PAn synthesized in the presence of the MF of 0.8 T reaches 5.88 S/cm,which is higher than that of the PAn synthesized in the absence of the MF. The thermal stability, the crystallinity and the doping degree of the PAn synthesized in the presence of the MF are also improved. MF not only enhances the conductivity, but also reduces the doping time, the dosage of the dopant and the oxidizing agent when the conductivity reaches the maximum.

  7. High-performance Liquid Chromatographic Determination of Urinary Trans, Trans-Muconic Acid Excreted by Workers Occupationally Exposed to Benzene

    Institute of Scientific and Technical Information of China (English)

    XIA-MIN HU; SHI-ZHEN SONG; FANG-LI YE; LI-WEN LIU

    2006-01-01

    To investigate the relationship between trans, trans-muconic acid (ttMA) as benzene metabolite of occupational workers and benzene concentration in air. Methods A rapid and sensitive high-performance liquid chromatography was developed to determine the level of urinary ttMA. ttMA was extrated from urinary samples in liquid-liquid phase a ODS (2) (5u) column (Φ4.6 mm× 150 mm) and detected at wavelength 264 nm in a UV detector using vanillic acid as an internal standard. The mobile phase was acetaticacid/tetrahydrofuran/methanol/water (v/v, 1:2:10:87). The method was validated with 56 urine samples collected from occupationally benzene-exposed individuals. Results A correlation coefficient (r = 0.9963 ) was found for ttMA ranging 0.10-10.00 μg/mL. The limit of detection was 0.10 μg/mL. The recovery and reproducibility were generally over 90%. There was a positive correlation between ttMA and benzene level in air. The equation was Y=0.859+0.108C (before work, r=-0.6200) or Y=1.980+0.179C (after work, r=0.7930). Conclusion This method can be used to determine and control the level of urinary ttMA in those who are occupationally exposed to benzene.

  8. Studies of Grafted and Sulfonated Spiro Poly(isatin-ethersulfone Membranes by Super Acid-Catalyzed Reaction

    Directory of Open Access Journals (Sweden)

    Lei Jin

    2016-03-01

    Full Text Available Spiro poly(isatin-ethersulfone polymers were prepared from isatin and bis-2,6-dimethylphenoxyphenylsulfone by super acid catalyzed polyhydroxyalkylation reactions. We designed and synthesized bis-2,6-dimethylphenoxyphenylsulfone, which is structured at the meta position steric hindrance by two methyl groups, because this structure minimized crosslinking reaction during super acid catalyzed polymerization. In addition, sulfonic acid groups were structured in both side chains and main chains to form better polymer chain morphology and improve proton conductivity. The sulfonation reactions were performed in two steps which are: in 3-bromo-1-propanesulfonic acid potassium salt and in con. sulfuric acid. The membrane morphology was studied by tapping mode atomic force microscope (AFM. The phase difference between the hydrophobic polymer main chain and hydrophilic sulfonated units of the polymer was shown to be the reasonable result of the well phase separated structure. The correlations of proton conductivity, ion exchange capacity (IEC and single cell performance were clearly described with the membrane morphology.

  9. Esterification Reaction of Glycerol and Palm Oil Oleic Acid Using Methyl Ester Sulfonate Acid Catalyst as Drilling Fluid Formulation

    Science.gov (United States)

    Sari, V. I.; Hambali, E.; Suryani, A.; Permadi, P.

    2017-02-01

    Esterification reaction between glycerol with palm oil oleic acid to produce glycerol ester and one of the utilization of glycerol esters is as ingredients of drilling fluids formula for oil drilling needs. The purpose of this research is to get the best conditions of the esterification process. The esterification reaction does with the reactants is glycerol with purity of 97.6%, palm oil oleic acid with the molar ratio is 1:1, Methyl Ester Sulfonate Acid (MESA) catalyst 0.5%, and stirring speed 400 rpm. The temperature range of 180°C to 240°C and the processing time between 120 to 180 minutes. The results showed that the best conditions of the esterification reaction at the temperature 240°C and time process are 180 minute. The increasing temperature resulted that the acid number decreases and causing the conversion increased. The maximum conversion is 99.24%, density 0.93 g/cm3, flash point 241°C, pour point -3°C, the boiling point of 244 °C, the acid value of 1.90 mg KOH/g sample, kinematic viscosity 31.51 cSt (40°C), surface tension 37.0526 dyne/cm and GCMS identification, glycerol ester at 22,256 retention time (minutes) and wide area 73.75 (%). From the research results obtained glycerol ester with characteristics suitable for drilling fluid formulations.

  10. Comparative Study on Single-Molecule Junctions of Alkane- and Benzene-Based Molecules with Carboxylic Acid/Aldehyde as the Anchoring Groups

    Science.gov (United States)

    Chen, Fang; Peng, Lin-Lu; Hong, Ze-Wen; Mao, Jin-Chuan; Zheng, Ju-Fang; Shao, Yong; Niu, Zhen-Jiang; Zhou, Xiao-Shun

    2016-08-01

    We have measured the alkane and benzene-based molecules with aldehyde and carboxylic acid as anchoring groups by using the electrochemical jump-to-contact scanning tunneling microscopy break junction (ECSTM-BJ) approach. The results show that molecule with benzene backbone has better peak shape and intensity than those with alkane backbone. Typically, high junction formation probability for same anchoring group (aldehyde and carboxylic acid) with benzene backbone is found, which contributes to the stronger attractive interaction between Cu and molecules with benzene backbone. The present work shows the import role of backbone in junction, which can guide the design molecule to form effective junction for studying molecular electronics.

  11. The effect of trinitrobenzene sulfonic acid on gut-derived smooth muscle cell arachidonic acid metabolism: role of endogenous prostanoids

    Directory of Open Access Journals (Sweden)

    W. E. Longo

    1997-01-01

    Full Text Available The contribution of smooth muscle cells as a potential source of eicosanoid production during inflammatory states remains to be elucidated. We investigated the effect of trinitrobenzene sulfonic acid (TNB, a known pro-inflammatory agent, on jejunal smooth muscle cell eicosanoid production. Human gut-derived smooth muscle cells (HISM were incubated with TNB for 1 hour. Additionally, some cells were preincubated with either dimethylthiourea, or indomethacin for 1 hour before exposure to identical concentrations of TNB. Incubation with TNB led to significant increases in PGE2 and 6-keto PGF-1α release, but not leukotriene B4 release; responses which were both inhibited by dimethylthiourea and indomethacin treatment. Our results suggest that gutderived smooth muscle cells may represent an important source of proinflammatory prostanoids but not leukotrienes during inflammatory states of the intestine. The inhibition of prostanoid activity by thiourea may be mediated by suppression of cyclooxygenase activity in this cell line.

  12. Removal of free fatty acid in Palm Fatty Acid Distillate using sulfonated carbon catalyst derived from biomass wastefor biodiesel production

    Science.gov (United States)

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

    2016-01-01

    In this research, the esterification of PFAD using the sulfonatedcoconut shell biochar catalyst was studied. Carbon solid catalysts were prepared by a sulfonation of carbonized coconut shells. The performances of the catalysts were evaluated in terms of the reaction temperatures, the molar ratios of methanol to PFAD, the catalyst loading and the reaction times. The reusability of the solid acid carbon catalysts was also studied in this work. The results indicated that the FFA conversion was significantly increased with increasing catalyst loading and reaction times. It can be concluded that the optimal conditions were an PFAD to methanol molar ratio of 1:12, the amount of catalyst of 10%w, and reaction temperature of 60oC.At this optimum condition, the conversion to biodieselreached 88%.

  13. Identification of 6-hydroxy-trans,trans-2,4-hexadienoic acid, a novel ring-opened urinary metabolite of benzene

    Energy Technology Data Exchange (ETDEWEB)

    Kline, S.A.; Robertson, J.F.; Grotz, V.L.; Goldstein, B.D.; Witz, G. (Robert Wood Johnson Medical School, Piscataway, NJ (United States) Environmental and Occupational Health Sciences Institute, Piscataway, NJ (United States))

    1993-09-01

    The authors have studied the in vivo metabolism of benzene in mice to ring-opened compounds excreted in urine. Male CD-1 mice were treated intraperitoneally with benzene (110-440 mg/kg), [[sup 14]C] benzene (220 mg/kg) or trans,trans-muconaldehyde (MUC; 4 mg/kg), a microsomal, hematotoxic metabolite of benzene. Urine, collected over 24 hr, was extracted and analyzed by HPLC with a diode-array detector and by scintillation counting. In addition to trans,trans-muconic acid, previously the only known ring-opened urinary benzene metabolite, a new metabolite, 6-hydroxy-trans,trans-2,4-hexadienoic acid, was detected in urine of mice treated with either benzene or MUC. The authors identified the new metabolite based on coelution of metabolites and UV spectral comparison with authentic standards in unmethylated and methylated urine extracts. Results presented here are consistent with the intermediacy of the ring-opened metabolites.

  14. Lack of sensitivity of urinary trans,trans-muconic acid in determining low-level (ppb) benzene exposure in children.

    Science.gov (United States)

    Barbieri, Anna; Accorsi, Antonio; Raffi, Giovanni Battista; Nicoli, Luciana; Violante, Francesco Saverio

    2002-01-01

    Benzene is a widespread pollutant of which the main source in the outside environment is automotive traffic. Benzene is also present in cigarette smoke, and small quantities exist in drinking water and food; all of these sources contribute to pollution of indoor environments. Benzene exposure may be studied with biologic indicators. In the present study, the authors evaluated whether differences in urinary concentrations of trans,transmuconic acid (t,t-MA) were detectable in a sample of 150 children and if the chemical was correlated with environmental exposures to low levels of benzene. The children attended primary schools that had significantly different-but low-environmental benzene levels. Analysis of urinary t,t-MA was achieved with high-performance liquid chromatography (photodiode array detector), and analysis of passive air samplers for benzene was performed with gas chromatography-mass spectrometry. Statistical analysis (Kruskal-Wallis test) indicated that differences in urinary levels of t,t-MA in children from urban and rural areas were not statistically significant (p = .07), nor were there significant differences between children with and without relatives who smoked (p = .69). As has been shown in other studies of children and adults, results of our study evidenced (1) the difficulty of correlating concentrations of urinary biomarkers with environmental exposure to benzene at a parts-per-billion level (i.e., traffic and environmental tobacco smoke) and, consequently, (2) the lack of specificity of t,t-MA as a biological indicator for the study of a population's exposure.

  15. Synthesis and solid-state NMR characterization of cubic mesoporous silica SBA-1 functionalized with sulfonic acid groups.

    Science.gov (United States)

    Tsai, Hui-Hsu Gavin; Chiu, Po-Jui; Jheng, Guang-Liang; Ting, Chun-Chiang; Pan, Yu-Chi; Kao, Hsien-Ming

    2011-07-01

    Well-ordered cubic mesoporous silicas SBA-1 functionalized with sulfonic acid groups have been synthesized through in situ oxidation of mercaptopropyl groups with H(2)O(2) via co-condensation of tetraethoxysilane (TEOS) and 3-mercaptopropyltrimethoxysilane (MPTMS) templated by cetyltriethylammonium bromide (CTEABr) under strong acidic conditions. Various synthesis parameters such as the amounts of H(2)O(2) and MPTMS on the structural ordering of the resultant materials were systematically investigated. The materials thus obtained were characterized by a variety of techniques including powder X-ray diffraction (XRD), multinuclear solid-state Nuclear Magnetic Resonance (NMR) spectroscopy, (29)Si{(1)H} 2D HETCOR (heteronuclear correlation) NMR spectroscopy, thermogravimetric analysis (TGA), and nitrogen sorption measurements. By using (13)C CPMAS NMR technique, the status of the incorporated thiol groups and their transformation to sulfonic acid groups can be monitored and, as an extension, to define the optimum conditions to be used for the oxidation reaction to be quantitative. In particular, (29)Si{(1)H} 2D HETCOR NMR revealed that the protons in sulfonic acid groups are in close proximity to the silanol Q(3) species, but not close enough to form a hydrogen bond.

  16. Esterification of oil adsorbed on palm decanter cake into methyl ester using sulfonated rice husk ash as heterogeneous acid catalyst

    Science.gov (United States)

    Hindryawati, Noor; Erwin, Maniam, Gaanty Pragas

    2017-02-01

    Palm Decanter cake (PDC) which is categorized as the waste from palm oil mill has been found to contain residual crude palm oil. The oil adsorbed on the PDC (PDC-oil) can be extracted and potentially used as feedstock for biodiesel production. Feedstock from waste like PDC-oil is burdened with high free fatty acids (FFAs) which make the feedstock difficult to be converted into biodiesel using basic catalyst. Therefore, in this study, a solid acid, RHA-SO3H catalyst was synthesized by sulfonating rice husk ash (RHA) with concentrated sulfuric acid. The RHA-SO3H prepared was characterized with TGA, FTIR, BET, XRD, FE-SEM, and Hammett indicators (methyl red, bromophenol blue, and crystal violet). PDC was found to have about 11.3 wt. % oil recovered after 1 hour extraction using ultrasound method. The presence of sulfonate group was observed in IR spectrum, and the surface area of RHA-SO3H was reduced to 37 m2.g-1 after impregnation of sulfonate group. The RHA-SO3H catalyst showed that it can work for both esterification of free fatty acid which is present in PDC-oil, and transesterification of triglycerides into methyl ester. The results showed highest methyl ester content of 70.2 wt.% at optimal conditions, which was 6 wt.% catalyst amount, methanol to oil molar ratio of 17:1 for 5 hours at 120 °C.

  17. Syntheses, crystal structures and antioxidant study of Zn(II) complexes with morin-5'-sulfonic acid (MSA).

    Science.gov (United States)

    Pieniążek, Elżbieta; Kalembkiewicz, Jan; Dranka, Maciej; Woźnicka, Elżbieta

    2014-12-01

    The study of modified synthetic procedure of water soluble morin-5'-sulfonic acid sodium salt (NaMSA) involving less aggressive chemicals and carried out at mild conditions was described. The NaMSA salt is a convenient source of anionic morin-5'-sulfonic ligand (MSA) in ion exchange reactions. The coordination ability of MSA ligand towards the zinc cations was investigated in aqueous solution and in solid state. Novel zinc complexes of morin-5'-sulfonate were obtained by a reaction of Zn(NO3)2 with morin-5'-sulfonate in water. Resulting compounds were characterized by single-crystal X-ray diffraction analysis, as well as spectral and thermal methods. The coordination interaction, hydrogen bond and π-π stacking lead to the formation of a 1D chain or 3D coordination polymers. The antioxidant activity of the Zn(II)-MSA complexes was evaluated by means of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method. In this work, we have shown that the studied compounds are more effective free radical scavengers than the natural flavonoids like plain morin.

  18. Synthesis and properties of poly(methyl methacrylate-2-acrylamido-2-methylpropane sulfonic acid)/PbS hybrid composite

    Energy Technology Data Exchange (ETDEWEB)

    Preda, N., E-mail: nicol@infim.ro [National Institute of Materials Physics, Multifunctional Materials and Structures Laboratory, P.O. Box MG-7, 77125 Bucharest (Romania); Rusen, E. [University Politehnica Bucharest, Department of Polymer Science, Calea Victoriei No. 71101, Bucharest (Romania); Musuc, A. [Institute of Physical Chemistry, 060021 Bucharest (Romania); Enculescu, M.; Matei, E. [National Institute of Materials Physics, Multifunctional Materials and Structures Laboratory, P.O. Box MG-7, 77125 Bucharest (Romania); Marculescu, B. [University Politehnica Bucharest, Department of Polymer Science, Calea Victoriei No. 71101, Bucharest (Romania); Fruth, V. [Institute of Physical Chemistry, 060021 Bucharest (Romania); Enculescu, I. [National Institute of Materials Physics, Multifunctional Materials and Structures Laboratory, P.O. Box MG-7, 77125 Bucharest (Romania)

    2010-08-15

    The synthesis of a new hybrid composite based on PbS nanoparticles and poly(methyl methacrylate-2-acrylamido-2-methylpropane sulfonic acid) [P(MMA-AMPSA)] copolymer is reported. The chemical synthesis consists in two steps: (i) a surfactant-free emulsion copolymerization between methyl methacrylate and 2-acrylamido-2-methylpropane sulfonic acid and (ii) the generation of PbS particles in the presence of the P(MMA-AMPSA) latex, from the reaction between lead nitrate and thiourea. The composite was studied by scanning electron microscopy (SEM), X-ray diffraction, FTIR spectroscopy, thermogravimetric analysis and differential scanning calorimetry. The microstructure observed using SEM proves that the PbS nanoparticles are well dispersed in the copolymer matrix. The X-ray diffraction measurements demonstrate that the PbS nanoparticles have a cubic rock salt structure. It was also found that the inorganic semiconductor nanoparticles improve the thermal stability of the copolymer matrix.

  19. 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)

  20. Sulfonated Polyetherimide and Its Membranes

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

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

  1. 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.

  2. p-toluene sulfonic acid doped polyaniline carbon nanotube composites: synthesis via different routes and modified properties

    OpenAIRE

    Sharma, Ashok K.; YASHPAL SHARMA

    2013-01-01

    Composites of polyaniline and carbon nanotube (CNT) were prepared by in-situ chemical polymerization method using various aniline concentrations in the initial polymerization solution with p-toluene sulfonic acid (PTS) as secondary dopant and mechanical mixing of the PANI and CNT using different weight ratios of PANI and CNTs. The structural characterizations of the composites were done by Fourier transform infrared (FTIR) and Ultra violet visible spectroscopy (UV-Visible). Scanning electron ...

  3. Construction and Study of Hetreojunction Solar Cell Based on Dodecylbenzene Sulfonic Acid-Doped Polyaniline/n-Si

    OpenAIRE

    Morsi, I.; Sh. Ebrahim; Soliman, M

    2012-01-01

    Polyaniline/n-type Si heterojunctions solar cell are fabricated by spin coating of soluble dodecylbenzene sulfonic acid (DBSA)-doped polyaniline onto n-type Si substrate. The electrical characterization of the Al/n-type Si/polyaniline/Au (Ag) structure was investigated by using current-voltage (I-V), capacitance-voltage (C-V), and impedance spectroscopy under darkness and illumination. The photovoltaic cell parameters, that is, open-circuit voltage (oc), short-circuit current density (sc), ...

  4. One-pot Synthesis of Bis(dihydropyrimidinone-4-yl)benzene Using Boric Acid as a Catalyst

    Institute of Scientific and Technical Information of China (English)

    TU Shu-Jiang; ZHU Xiao-Tong; FANG Fang; ZHANG Xiao-Jing; ZHU Song-Lei; LI Tuan-Jie; SHI Da-Qing; WANG Xiang-Shan; JI Shun-Jun

    2005-01-01

    A simple effective synthesis of bis(dihydropyrimidinone-4-yl)benzene derivatives, using boric acid as catalyst,from isophthalic aldehyde or terephthalic aldehyde, 1,3-dicarbonyl compounds and urea or thiourea in glacial acetic acid was described. As the expansion of the classical Biginelli reaction, this method has the advantage of excellent yields 83%-94% and short reaction time 0.5-1.5 h.

  5. Assessment of perfluorooctane sulfonate and perfluorooctanoic acid exposure through fish consumption in Italy

    Directory of Open Access Journals (Sweden)

    Andrea Barbarossa

    2016-11-01

    Full Text Available Perfluoroalkyl and polyfluoroalkyl substances (PFASs are pollutants of anthropic origin with possible side effects on human health. Diet, and in particular fish and seafood, is considered the major intake pathway for humans. The present study investigated the levels of perfluorooctane sulfonate (PFOS and perfluorooctanoic acid (PFOA contamination in twenty-five samples of fresh fillet of five widely consumed fish species purchased from large retailers in Italy, to be used for an estimation of the Italian population exposure to these contaminants. PFOS and PFOA were found in all samples, at concentrations up to 1896 (mean=627 ng/kg and 487 ng/kg (mean=75 ng/kg, respectively, confirming the role of fish as high contributor to human exposure. However, a remarkable inter-species variability was observed, and multiple factors were suggested as potentially responsible for such differences, suggesting that the preferential consumption of certain species could likely increase the intake, and thus the exposure. The exposure estimates for both average and high fish consumers resulted far below the tolerable daily intakes for PFOS and PFOA in all age groups, confirming the outcomes of EFSA’s scientific report. In particular, the calculated total dietary exposure for the 95th percentile consumers belonging to the toddler age class, the most exposed group, resulted equal to 9.72 ng/kg body weight (BW/day for PFOS and 8.39 ng/kg BW/day for PFOA.

  6. 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.

  7. Colorimetric detection of Cd2+ using 1-amino-2-naphthol-4-sulfonic acid functionalized silver nanoparticles

    Science.gov (United States)

    Huang, Pengcheng; Liu, Bowen; Jin, Weiwei; Wu, Fangying; Wan, Yiqun

    2016-11-01

    A colorimetric assay has been developed for facile, rapid, and sensitive detection of Cd2+ using 1-amino-2-naphthol-4-sulfonic acid functionalized silver nanoparticles (ANS-AgNPs). The presence of Cd2+ induces the aggregation of ANS-AgNPs through cooperative metal-ligand interaction. As a result, the characteristic surface plasmon resonance (SPR) peak of ANS-AgNPs at 390 nm was red-shifted to 580 nm, yielding a color change from bright yellow to reddish-brown. The color change is monitored by UV-Vis spectrometer and can be directly read out by the naked eye. Under the optimized conditions, a good linear relationship (correlation coefficient R = 0.997) was obtained between the ratio of the absorbance at 580 nm to that at 390 nm (A580nm/A390nm) and the concentration of Cd2+ over the range of 1.0-10 μM with detection limit of 87 nM. The proposed method is simple and efficient, which has been applied for determining Cd2+ in milk powder, serum, and lake water with satisfactory results.

  8. 脂肪酸甲酯磺酸盐%Fatty acid methyl ester sulfonate

    Institute of Scientific and Technical Information of China (English)

    韩建英

    2012-01-01

    Fatty acid methyl ester sulfonate(MES) is an anionic surfactant based on natural oils generated from plant and animal as raw materials. MES has good detergency, lime soap dispersing ability, hard water-resistance, emulsibility, water-solubility and biodegradability; besides, it can improve the solubility of soap in water. Because of the good performance of MES, it can be used in synthetic powder detergent, compound soap powder, composite soap, shampoo and personal care products. The present production situation, product forms, properties as well as applications of MES were related.%脂肪酸甲酯磺酸盐简称(MES)是以天然动植物油脂为原料制得的脂肪酸系阴离子表面活性剂。它具有良好的去污性、钙皂分散性、抗硬水性、乳化性、增溶性和生物降解性,并能改进肥皂的溶解性。由于MES性能优良,主要用于合成洗衣粉、复合皂粉、复合肥皂、香波以及个人清洁用品中。对MES的生产现状、产品形式、性能以及应用进行了概述。

  9. Ion-specific swelling of poly(styrene sulfonic acid) hydrogel.

    Science.gov (United States)

    Xu, Ling; Li, Xin; Zhai, Maolin; Huang, Ling; Peng, Jing; Li, Jiuqiang; Wei, Genshuan

    2007-04-05

    Poly(styrene sulfonic acid) (PSSA) hydrogel was prepared by radiation crosslinking using methyl N,N-bis-acrylamide as crosslinker. Effects of ion species and concentration on the swelling behavior of PSSA hydrogel were investigated in aqueous solution of selected anions (F-, Cl-, Br-, SCN-), cations (Li+, Na+, K+, Ca2+), and hydrophobic ions (tetramethylammonium cation TMA+, tetrabutylammonium cation TBA+, and dodecyltrimethylammonium cation TAB+). The deswelling extent of PSSA hydrogel follows anion Hofmeister series, i.e., SCN- < Br- < Cl- < F-, in solutions containing selected anions and K+ as counterion up to a concentration of 2 mol.L(-1). On the contrary, the deswelling extent of PSSA hydrogel in solutions containing selected cations and Cl- follows the sequence of Li+ < Na+ < K+ < Ca2+, which is the reverse of the Hofmeister series except Ca2+. We have discussed the effects of ions on the hydrogen bonding through SO3- and phenyl ring in salt solutions at low and high concentrations. Other interactions, such as the cation-pi and hydrophobic interactions, also contributed to the ion-specific swelling of PSSA hydrogel. The proposed mechanism was further elucidated by FTIR and NMR analysis. A very specific deswelling-reswelling phenomenon of PSSA hydrogel in KF solution has been observed and ascribed to the F- binding to phenyl ring through a specific interaction.

  10. Effect of Dodecylbenzene Sulfonic Acid Used as Additive on Residue Hydrotreating

    Institute of Scientific and Technical Information of China (English)

    Sun Yudong; Yang Chaohe

    2015-01-01

    The effect of additive—dodecylbenzene sulfonic acid (DBSA)—on residue hydrotreating was studied in the au-toclave. The results showed that the additive improved stabilization of the colloid system of residue, which could delay the aggregation and coke formation from asphaltenes on the catalyst, and make heavy components transformed into light oil. The residue conversion in the presence of this additive increased by 1.94%, and the yield of light oil increased by 1.53% when the reaction time was 90 min. The surface properties of the catalyst in the presence of this additive were better than that of the blank test within a very short time (30 min) and deteriorated rapidly after a longer reaction time due to higher conversion and coke deposition. Compared with the blank test, the case using the said additive had shown that the structure of hydrotreated asphaltene units was smaller and the condensation degrees were higher. The test results indicated that the additive could improve the hydrotreating reactivity of residue via permeation and depolymerization, the heavier components could be transformed into light oil more easily, and the light oil yield and residue conversion were higher for the case using the said additive in residue hydrotreating process.

  11. PREPARATION,CHARACTERIZATION AND ELECTROCHEMICAL PROPERTIES OF POLYPYRROLE-POLYSTYRENE SULFONIC ACID COMPOSITE FILM

    Institute of Scientific and Technical Information of China (English)

    Liang-ti Qu; Gao-quan Shi; Chen Liu; Jin-ying Yuan; Wen-bin Qian

    2005-01-01

    Polypyrrole-polystyrene sulfonic acid (PPy-PSSA) composite films have been electrosynthesized in an aqueous solution of PSSA. The electro-active films exhibit cation exchange during the redox process. Infrared, Raman and energydispersive spectroscopic results demonstrated that the polyanion of PSS- is co-deposited into the PPy matrix and couldn't be stripped from the film extensively by dedoping. The doping level together with dipolaron content of the PPy-PSSA composite film increases during electrochemical polymerization process. SEM images revealed that the composite film has smooth and compact morphology and AFM pictures suggested that PPy chains are possibly grown perpendicular to the electrode surface. TGA tests indicated that the composite films has much better thermal stability than that of pure PPy.Furthermore, electrochemical studies showed that the relaxation process at certain holding potential has great effect on the shape of the cyclic voltammetric curves of PPy-PSSA composite film. The composite film exhibits cation and anion exchange during the redox process after undergoing the relaxation step. It is more difficult for divalent anion to enter the polymer matrix than a univalent ion, and a large cation such as (CH3CH2CH2CH2)4N+ cannot be involved in the ion exchange process.

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

    Institute of Scientific and Technical Information of China (English)

    汤琳; 袁峻峰; 陈德辉

    2000-01-01

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

  13. Proton conducting membranes based on benzimidazole sulfonic acid doped sulfonated poly(oxadiazole-triazole) copolymer for low humidity operation

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-07-15

    This work reports for the first time the preparation of sulphonated poly(oxadiazole-triazole) copolymer membranes doped with amphoteric molecule, 1H-benzimidazole-2-sulphonic acid and their characterisation as proton conductors at 120 C and low humidity. The membranes had not only high proton conductivities, up to 4 x 10{sup -3} S cm{sup -1} at 120 C and low relative humidity (5 and 10%), but also had good mechanical properties with a storage modulus of about 3 GPa at 300 C and high thermal stability with T{sub g} up to around 420 C. Because of their superior ion conducting and mechanical properties they have potential as a proton conducting membrane for fuel cell applications, in particular at high temperature and extremely low-humidity conditions. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  14. Removal of perfluorooctanoic acid and perfluorooctane sulfonate via ozonation under alkaline condition

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Angela Yu-Chen, E-mail: yuchenlin@ntu.edu.tw [Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Rd., Taipei 106, Taiwan (China); Panchangam, Sri Chandana; Chang, Cheng-Yi [Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Rd., Taipei 106, Taiwan (China); Hong, P.K. Andy [Department of Civil and Environmental Engineering, University of Utah, Salt Lake City, Utah 84112 (United States); Hsueh, Han-Fang [Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Rd., Taipei 106, Taiwan (China)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer PFOA and PFOS are degraded by O{sub 3} or O{sub 3}/H{sub 2}O{sub 2} treatment at pH 11. Black-Right-Pointing-Pointer Degradation of PFOA and PFOS by O{sub 3} or O{sub 3}/H{sub 2}O{sub 2} under alkaline condition is enhanced when the compounds are pretreated by 15 min of ozonation at ambient pH (4-5). Black-Right-Pointing-Pointer PFOA and PFOS removal by O{sub 3} or O{sub 3}/H{sub 2}O{sub 2} at pH 11 was efficient relative to existing methods in terms of energy and contact time. - Abstract: The elimination of recalcitrant, ubiquitous perfluoroalkyl acids (PFAAs) such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) is desirable for reducing potential human health and environmental risks. We here report the degradation of PFOA and PFOS by 85-100% via ozonation under alkaline condition being studied at environmentally relevant contaminant concentrations of 50 {mu}g L{sup -1} to 5 mg L{sup -1}, with enhanced removal rates by addition of hydrogen peroxide. Enhanced removal is achieved by ozonation pretreatment for 15 min at the ambient pH (i.e. 4-5), followed by elevation of pH to 11 and continued ozonation treatment for 4 h. The ozonation pretreatment resulted in increased degradation of PFOA by 56% and PFOS by 42%. The results indicated hydroxyl radical-driven degradation of PFOA and PFOS in both treatments by ozone and peroxone under alkaline conditions. Wastewaters from electronics and semiconductor fabrication plants in the Science Park of Hsinchu city, Taiwan containing PFOA and PFOS have been readily treated by ozonation under alkaline condition. Treatment of PFAAs by ozone or peroxone proves to be efficient in terms of energy requirement, contact time, and removal rate.

  15. Extraneous carbon assessment in ultra-microscale radiocarbon analysis using benzene polycarboxylic acids (BPCA)

    Science.gov (United States)

    Hanke, Ulrich M.; McIntyre, Cameron P.; Schmidt, Michael W. I.; Wacker, Lukas; Eglinton, Timothy I.

    2016-04-01

    Measurements of the natural abundance of radiocarbon (14C) concentrations in inorganic and organic carbon-containing materials can be used to investigate their date of origin. Particularly, the biogeochemical cycling of specific compounds in the environment may be investigated applying molecular marker analyses. However, the isolation of specific molecules from environmental matrices requires a complex processing procedure resulting in small sample sizes that often contain less than 30 μg C. Such small samples are sensitive to extraneous carbon (Cex) that is introduced during the purification of the compounds (Shah and Pearson, 2007). We present a thorough radiocarbon blank assessment for benzene polycarboxylic acids (BPCA), a proxy for combustion products that are formed during the oxidative degradation of condensed polyaromatic structures (Wiedemeier et al, in press). The extraneous carbon assessment includes reference material for (1) chemical extraction, (2) preparative liquid chromatography (3) wet chemical oxidation which are subsequently measured with gas ion source AMS (Accelerator Mass Spectrometer, 5-100 μg C). We always use pairs of reference materials, radiocarbon depleted (14Cfossil) and modern (14Cmodern) to determine the fraction modern (F14C) of Cex.Our results include detailed information about the quantification of Cex in radiocarbon molecular marker analysis using BPCA. Error propagation calculations indicate that ultra-microscale samples (20-30 μg) are feasible with uncertainties of less than 10 %. Calculations of the constant contamination reveal important information about the source (F14C) and mass (μg) of Cex (Wacker and Christl, 2011) for each sub procedure. An external correction of compound specific radiocarbon data is essential for robust results that allow for a high degree of confidence in the 14C results. References Shah and Pearson, 2007. Ultra-microscale (5-25μg C) analysis of individual lipids by 14C AMS: Assessment and

  16. 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...... it was found to be higher than 10/sup -2/ S cm/sup -1/. Much improvement in the mechanical strength is observed for the blend polymer membranes, especially at higher temperatures. Preliminary work has demonstrated the feasibility of these polymeric membranes for fuel-cell applications...

  17. Optimization of SPE for Analysis of Mandelic Acid as a Biomarker of Exposure to Ethyl Benzene

    Directory of Open Access Journals (Sweden)

    SJ Shahtaheri, M Abdollahi, F Golbabaei, A Rahimi-Froushani, F Ghamari

    2004-10-01

    Full Text Available Ethyl benzene is an important constituent of widely used solvents in industries and laboratories, causing widespread environmental and industrial pollutions. For evaluation of occupational exposure to such pollutants, biological monitoring is an essential process, in which, preparation of environmental and biological samples is one of the most time-consuming and error-prone aspects prior to chromatographic techniques. The use of solid-phase extraction (SPE has been grown and is a fertile technique of sample preparation as it provides better results than those of liquid-liquid extraction (LLE. In this study, SPE using bonded silica has been optimized with regard to sample pH, sample concentration, elution solvent, elution volume, sorbent type, and sorbent mass. Through experimental evaluation, a strong anion exchange silica cartridge (SAX has been found successful in simplifying sample preparation. The present approach proved that, mandelic acid could be retained on SAX sorbent based on specific interaction. Further study was employed using 10% acetic acid to extract the analyte from spiked urine and gave a clean sample for HPLC-UV system. In this study, a high performance liquid chromatography, using reverse-phase column was used. The isocratic run was done at a constant flow rate of 0.85 ml/min, the mobile phase was water/methanol/acetic acid and a UV detector was used, setting at 225 nm. At the developed conditions the extraction recovery was exceeded 98%. The factors were evaluated statically and also validated with three different pools of spiked urine samples and showed a good reproducibility over six consecutive days as well as six within-day experiments.

  18. Synthesis of highly phosphonic acid functionalized benzene-bridged periodic mesoporous organosilicas for use as efficient dye adsorbents

    Energy Technology Data Exchange (ETDEWEB)

    Deka, Juti Rani; Liu, Chia-Ling; Wang, Tzu-Hua; Chang, Wei-Chieh; Kao, Hsien-Ming, E-mail: hmkao@cc.ncu.edu.tw

    2014-08-15

    Highlights: • Synthesis of highly phosphonic acid functionalized benzene-bridged PMOs. • Phosphonic acid loaded PMOs as adsorbent for cationic and anionic dyes. • Due to electrostatic interaction the adsorbent has high dye adsorption capacity. • π–π stacking interaction between benzene and dye enhances adsorption capacity. • Intraparticle diffusion played a dominant role in the adsorption process. - Abstract: Periodic mesoporous organosilicas (PMOs) with benzene bridging groups in the silica wall were functionalized with a tunable content of phosphonic acid groups. These bifunctional materials were synthesized by co-condensation of two different organosilane precursors, that is, 1,4-bis(triethoxysilyl)benzene (BTEB) and sodium 3-(trihydroxysilyl)propyl methyl phosphate (SPMP), under acidic conditions using nonionic surfactant Brij-S10 as template. The materials exhibited well-ordered mesostructures and were characterized by X-ray diffraction, nitrogen sorption, TEM, TGA, FTIR, and solid-state NMR measurements. The materials thus obtained were employed as adsorbents to remove different types of dyes, for example, cationic dyes methylene blue and phenosafranine, anionic orange II, and amphoteric rhodamine B, from aqueous solutions. The materials exhibited a remarkably high adsorption capacity than activated carbon due to their ordered mesostructures, a large number of phosphonic acid groups, and high surface areas. The adsorption was mainly governed by electrostatic interaction, but also involved π–π stacking interaction as well as hydrogen bonding. The adsorption kinetics can be better fitted by the pseudo-second order model. The adsorption process was controlled by the mechanisms of external mass transfer and intraparticle diffusion. The materials retained more than 97% dye removal efficiency after use for five consecutive cycles.

  19. Occurrence of Perfluorooctanoic Acid and Perfluorooctane Sulfonate in Milk and Yogurt and Their Risk Assessment

    Directory of Open Access Journals (Sweden)

    Zhenni Xing

    2016-10-01

    Full Text Available Although perfluorooctanoic acid (PFOA and perfluorooctane sulfonate (PFOS have been identified in milk and dairy products in many regions, knowledge on their occurrence in Xinjiang (China is rare. This study was conducted to measure the levels of PFOA and PFOS in milk and yogurt from Xinjiang and to investigate the average daily intake (ADI of these two compounds. PFOA and PFOS levels were analyzed using ultrasonic extraction with methanol and solid-phase extraction followed by liquid chromatography–mass spectrometry. Retail milk and yogurt samples present higher detection rates (39.6% and 48.1% and mean concentrations (24.5 and 31.8 ng/L of PFOS than those of PFOA (33.0% and 37.0%; 16.2 and 22.6 ng/L, respectively. For raw milk samples, only PFOS was detected. The differences in the levels of the two compounds between samples from the north and south regions were observed, and northern regions showed higher pollution levels than southern regions. On the basis of the retail milk measurements and consumption data, the ADIs of PFOA and PFOS for Xinjiang adults were calculated to be 0.0211 and 0.0318 ng/kg/day, respectively. Furthermore, the estimated intakes of PFOA and PFOS varied among different groupings (age, area, gender, and race and increased with increasing age. Relevant hazard ratios were found to be far less than 1.0, and this finding suggested that no imminent health damages were produced by PFOA and PFOS intake via milk and yogurt consumption in the Xinjiang population.

  20. Toxicity of perfluorooctane sulfonate and perfluorooctanoic acid to plants and aquatic invertebrates.

    Science.gov (United States)

    Li, Mei-Hui

    2009-02-01

    Acute toxicities of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) were tested on four freshwater species and three plant species. PFOS was more toxic than PFOA for all species tested in this study. Similar time-response patterns of PFOS and PFOA toxicity were observed for each tested species. Values of the 48-h LC(50) of PFOS for all test species ranged from 27 to 233 mg/L and values of the 96-h LC(50) for three of the species ranged from 10 to 178 mg/L. Values of the 48-h LC(50) of PFOA for all test species ranged from 181 to 732 mg/L and values of the 96-h LC(50) for three of the species ranged from 337 to 672 mg/L. The most sensitive freshwater species to PFOS was green neon shrimp (Neocaridina denticulate) with a 96-h LC(50) of 10 mg/L. Of the aquatic organisms tested, the aquatic snail (Physa acuta) always has the highest resistance to PFOS or PFOA toxicity over each exposure period. Both PFOS and PFOA had no obvious adverse effect on seed germination for all three plant species. Five-day EC(50) of root elongation was more sensitive to LC(50) of seed germination in this study. Based on EC(10), EC(50), and NOECs, the 5-day root elongation sensitivity of test plants to both PFOS and PFOA was in the order of lettuce (Lactuca sativa) > pakchoi (Brassica rapa chinensis) > cucumber (Cucumis sativus). Based on the results of this study and other published literature, it is suggested that current PFOS and PFOA levels in freshwater may have no acute harmful ecological impact on the aquatic environment. However, more research on the long-term ecological effects of PFOS and PFOA on aquatic fauna are needed to provide important information to adequately assess ecological risk of PFOS and PFOA.

  1. Pistacia lentiscus resin regulates intestinal damage and inflammation in trinitrobenzene sulfonic acid-induced colitis.

    Science.gov (United States)

    Gioxari, Aristea; Kaliora, Andriana C; Papalois, Apostolos; Agrogiannis, George; Triantafillidis, John K; Andrikopoulos, Nikolaos K

    2011-11-01

    Mastic (Pistacia lentiscus) of the Anacardiaceae family has exhibited anti-inflammatory and antioxidant properties in patients with Crohn's disease. This study was based on the hypothesis that mastic inhibits intestinal damage in inflammatory bowel disease, regulating inflammation and oxidative stress in intestinal epithelium. Four different dosages of P. lentiscus powder in the form of powder were administered orally to trinitrobenzene sulfonic acid-induced colitic rats. Eighty-four male Wistar rats were randomly assigned to seven groups: A, control; B, colitic; C-F, colitic rats daily supplemented with P. lentiscus powder at (C) 50 mg/kg, (D) 100 mg/kg, (E) 200 mg/kg, and (F) 300 mg/kg of body weight; and G, colitic rats treated daily with cortisone (25 μg/kg of body weight). Colonic damage was assessed microscopically. The cytokines tumor necrosis factor-α, intercellular adhesion molecule-1 (ICAM-1), interleukin (IL)-6, IL-8, and IL-10 and malonaldehyde were measured in colonic specimens. Results were expressed as mean ± SE values. Histological amelioration of colitis (P≤.001) and significant differences in colonic indices occurred after 3 days of treatment. Daily administration of 100 mg of P. lentiscus powder/kg of body weight decreased all inflammatory cytokines (P≤.05), whereas 50 mg of P. lentiscus powder/kg of body weight and cortisone treatment reduced only ICAM-1 (P≤.05 and P≤.01, respectively). Malonaldehyde was significantly suppressed in all treated groups (P≤.01). IL-10 remained unchanged. Cytokines and malonaldehyde remained unaltered after 6 days of treatment. Thus P. lentiscus powder could possibly have a therapeutic role in Crohn's disease, regulating oxidant/antioxidant balance and modulating inflammation.

  2. Benzene Exposure Alters Expression of Enzymes Involved in Fatty Acid β-Oxidation in Male C3H/He Mice

    Directory of Open Access Journals (Sweden)

    Rongli Sun

    2016-10-01

    Full Text Available Benzene is a well-known hematotoxic carcinogen that can cause leukemia and a variety of blood disorders. Our previous study indicated that benzene disturbs levels of metabolites in the fatty acid β-oxidation (FAO pathway, which is crucial for the maintenance and function of hematopoietic and leukemic cells. The present research aims to investigate the effects of benzene on changes in the expression of key enzymes in the FAO pathway in male C3H/He mice. Results showed that benzene exposure caused reduced peripheral white blood cell (WBC, red blood cell (RBC, platelet (Pit counts, and hemoglobin (Hgb concentration. Investigation of the effects of benzene on the expression of FA transport- and β-oxidation-related enzymes showed that expression of proteins Cpt1a, Crat, Acaa2, Aldh1l2, Acadvl, Crot, Echs1, and Hadha was significantly increased. The ATP levels and mitochondrial membrane potential decreased in mice exposed to benzene. Meanwhile, reactive oxygen species (ROS, hydrogen peroxide (H2O2, and malondialdehyde (MDA levels were significantly increased in the benzene group. Our results indicate that benzene induces increased expression of FA transport and β-oxidation enzymes, mitochondrial dysfunction, and oxidative stress, which may play a role in benzene-induced hematotoxicity.

  3. Degradation and contamination of perfluorinated sulfonic acid membrane due to swelling-dehydration cycles

    DEFF Research Database (Denmark)

    Andersen, Shuang Ma; Morgen, Per; Skou, Eivind Morten

    to the membrane degradation in direct methanol fuel cells (DMFCs), where liquid water has direct contact with the electrolyte. An ex-situ experiment was established with swelling-dehydration cycles on the membrane. However, formation of sulfonic anhydride was not detected during the entire treatment; instead...... contamination from calcium was found the primary reason for the deterioration of the membrane properties....

  4. Electrochemical synthesis of polyaniline/poly(2-acryl-amido-2-methyl-1-propane-sulfonic acid) composite

    Energy Technology Data Exchange (ETDEWEB)

    Lapkowski, M. (Inst. of Physical Chemistry and Technology of Polymers, Silesian Technical Univ., Gliwice (Poland))

    1993-03-22

    Conducting polyaniline/poly(2-acryl-amido-2-methyl-1-propane sulfonic acid) (PANi/PAMPS) composite films were synthesized electrochemically on platinum electrodes using a 10% aqueous PAMPS solution as the electrolyte. The electrochemical properties of the resulting polymer are similar to those observed for polyaniline doped with classical non-polymeric anions. PANi/PAMPS exhibits high cycling stability within the potential range of the first redox couple, but it undergoes degradation when the potential range characteristic of the second redox couple is reached. The degradation occurs independently of the electrolytic medium (HCl or 10% aqueous PAMPS). (orig.)

  5. Silylation of Alcohols and Phenols with Hexamethyldisilazane over Highly Reusable Propyl Sulfonic Acid Functionalized Nanostructured SBA-15

    Institute of Scientific and Technical Information of China (English)

    Daryoush ZAREYEE; Rezvaneh ASGHARI; Mohammad A. KHALILZADEH

    2011-01-01

    Various alcohols and phenols were trimethylsilylated in excellent yields using hexamethyldisilazane in the presence of catalytic amounts of environmentally friendly,hydrophobic,highly thermal stable,and completely heterogeneous sulfonic acid functionalized mesostructured SBA-15 in dichloromethane at ambient temperature.Primary,bulky secondary,tertiary,and phenolic hydroxyl functional groups were transformed to the corresponding trimethylsilyl ethers in excellent yields.The simple experimental procedure was accompanied by easy recovery and the catalyst was reusable (at least 18 reaction cycles); these are attractive features of this protocol.

  6. Characterization, Quantification and Compound-specific Isotopic Analysis of Pyrogenic Carbon Using Benzene Polycarboxylic Acids (BPCA).

    Science.gov (United States)

    Wiedemeier, Daniel B; Lang, Susan Q; Gierga, Merle; Abiven, Samuel; Bernasconi, Stefano M; Früh-Green, Gretchen L; Hajdas, Irka; Hanke, Ulrich M; Hilf, Michael D; McIntyre, Cameron P; Scheider, Maximilian P W; Smittenberg, Rienk H; Wacker, Lukas; Wiesenberg, Guido L B; Schmidt, Michael W I

    2016-05-16

    Fire-derived, pyrogenic carbon (PyC), sometimes called black carbon (BC), is the carbonaceous solid residue of biomass and fossil fuel combustion, such as char and soot. PyC is ubiquitous in the environment due to its long persistence, and its abundance might even increase with the projected increase in global wildfire activity and the continued burning of fossil fuel. PyC is also increasingly produced from the industrial pyrolysis of organic wastes, which yields charred soil amendments (biochar). Moreover, the emergence of nanotechnology may also result in the release of PyC-like compounds to the environment. It is thus a high priority to reliably detect, characterize and quantify these charred materials in order to investigate their environmental properties and to understand their role in the carbon cycle. Here, we present the benzene polycarboxylic acid (BPCA) method, which allows the simultaneous assessment of PyC's characteristics, quantity and isotopic composition ((13)C and (14)C) on a molecular level. The method is applicable to a very wide range of environmental sample materials and detects PyC over a broad range of the combustion continuum, i.e., it is sensitive to slightly charred biomass as well as high temperature chars and soot. The BPCA protocol presented here is simple to employ, highly reproducible, as well as easily extendable and modifiable to specific requirements. It thus provides a versatile tool for the investigation of PyC in various disciplines, ranging from archeology and environmental forensics to biochar and carbon cycling research.

  7. Nanostructured bacterial cellulose-poly(4-styrene sulfonic acid) composite membranes with high storage modulus and protonic conductivity.

    Science.gov (United States)

    Gadim, Tiago D O; Figueiredo, Andrea G P R; Rosero-Navarro, Nataly C; Vilela, Carla; Gamelas, José A F; Barros-Timmons, Ana; Neto, Carlos Pascoal; Silvestre, Armando J D; Freire, Carmen S R; Figueiredo, Filipe M L

    2014-05-28

    The present study reports the development of a new generation of bio-based nanocomposite proton exchange membranes based on bacterial cellulose (BC) and poly(4-styrene sulfonic acid) (PSSA), produced by in situ free radical polymerization of sodium 4-styrenesulfonate using poly(ethylene glycol) diacrylate (PEGDA) as cross-linker, followed by conversion of the ensuing polymer into the acidic form. The BC nanofibrilar network endows the composite membranes with excellent mechanical properties at least up to 140 °C, a temperature where either pure PSSA or Nafion are soft, as shown by dynamic mechanical analysis. The large concentration of sulfonic acid groups in PSSA is responsible for the high ionic exchange capacity of the composite membranes, reaching 2.25 mmol g(-1) for a composite with 83 wt % PSSA/PEGDA. The through-plane protonic conductivity of the best membrane is in excess of 0.1 S cm(-1) at 94 °C and 98% relative humidity (RH), decreasing to 0.042 S cm(-1) at 60% RH. These values are comparable or even higher than those of ionomers such as Nafion or polyelectrolytes such as PSSA. This combination of electric and viscoelastic properties with low cost underlines the potential of these nanocomposites as a bio-based alternative to other polymer membranes for application in fuel cells, redox flow batteries, or other devices requiring functional proton conducting elements, such as sensors and actuators.

  8. Evaluation of the toxicological effects of perfluorooctane sulfonic acid in the common carp (Cyprinus carpio)

    Energy Technology Data Exchange (ETDEWEB)

    Hoff, P.T.; Dongen, W. van; Esmans, E.L.; Blust, R.; Coen, W.M. de

    2003-02-26

    In the present study we evaluated the toxicological effects of a scarcely documented environmental pollutant, perfluorooctane sulfonic acid (PFOS), on selected biochemical endpoints in the common carp, Cyprinus carpio. Juvenile organisms were exposed to PFOS through a single intraperitoneal injection (liver concentrations ranging from 16 to 864 ng/g after 5 days of exposure) and after 1 and 5 days effects were assessed in liver and serum of the exposed organisms. The investigation of the hepatotoxicity of PFOS included the determination of the peroxisome proliferating potential (peroxisomal palmitoyl CoA oxidase and catalase activity) and the compounds influence on the average DNA basepair length (ABPL) by agarose gel electrophoresis. Total antioxidant activity (TAA), cholesterol and triglyceride levels were monitored in the serum. After 1 day of exposure the ABPL was significantly increased in the 270 and 864 ng/g treatment groups. After 5 days of exposure significant increases relative to the control were observed for the 16, 270 and 864 ng/g treatment groups. Enzyme leakage from the liver was investigated by measurement of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities in the serum. At 561, 670 and 864 ng/g PFOS a significant increase in serum ALT activity became apparent after 5 days of exposure with values ranging from 159 to 407% relative to the control. For serum AST activity a significant increase for the 864 ng/g treatment group was observed with a value of 112% relative to the control. Determination of the polymorphonuclear leukocyte migration into liver tissue as assessed through myeloperoxidase (MPO) activity in liver, was used as an indicator for inflammation. It appeared that inflammation was not involved in the observed membranous enzyme leakage for the 561, 670 and 864 ng/g PFOS treatment groups. The results of this study suggest that PFOS induces inflammation-independent enzyme leakage through liver cell membranes

  9. Gas chromatography/mass spectrometric analysis of methyl esters of N,N-dialkylaminoethane-2-sulfonic acids for verification of the Chemical Weapons Convention.

    Science.gov (United States)

    Pardasani, Deepak; Gupta, Arvinda K; Palit, Meehir; Shakya, Purushottam; Kanaujia, Pankaj K; Sekhar, K; Dubey, Devendra K

    2005-01-01

    This paper describes the synthesis and gas chromatography/electron ionization mass spectrometric (GC/EI-MS) analysis of methyl esters of N,N-dialkylaminoethane-2-sulfonic acids (DAESAs). These sulfonic acids are important environmental signatures of nerve agent VX and its toxic analogues, hence GC/EI-MS analysis of their methyl esters is of paramount importance for verification of the Chemical Weapons Convention. DAESAs were prepared by condensation of 2-bromoethane sulfonic acid with dialkylamines, and by condensation of dialkylaminoethyl chloride with sodium bisulfite. GC/EI-MS analysis of methyl esters of DAESAs yielded mass spectra; based on these spectra, generalized fragmentation routes are proposed that rationalize most of the characteristic ions.

  10. Proton-conducting electrolyte membranes based on hyperbranched polymer with a sulfonic acid group for high-temperature fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Takahito, E-mail: itoh@chem.mie-u.ac.j [Division of Chemistry for Materials, Graduate School of Engineering, Mie University, 1577 Kurima Machiya-cho, Tsu, Mie 514-8507 (Japan); Sakakibara, Takahiro; Takagi, Yuki; Tamura, Masashi; Uno, Takahiro; Kubo, Masataka [Division of Chemistry for Materials, Graduate School of Engineering, Mie University, 1577 Kurima Machiya-cho, Tsu, Mie 514-8507 (Japan); Aihara, Yuichi [Samsung Yokohama Research Institute, 2-7 Sugasawa-cho, Tsurumi-ku, Yokohama 230-0027 (Japan)

    2010-01-25

    The hyperbranched polymers (HBP-SA-Acs) with both a sulfonic acid group as a functional group and an acryloyl group as a cross-linker at terminals in different ratios of sulfonic acid group/acryloyl group (SO{sub 3}H/Ac) were successfully synthesized as a new thermally stable proton-conducting electrolyte. The cross-linked hyperbranched polymer electrolyte membranes (CL-HBP-SAs) were prepared by thermal polymerizations of the HBP-SA-Acs using benzoyl peroxide, and their ionic conductivities under dry condition and thermal properties were investigated. The ionic conductivities of the CL-HBP-SAs were found to be in the range of 2.2 x 10{sup -4} to 3.3 x 10{sup -6} S/cm, depending upon the SO{sub 3}H unit contents, at 150 deg. C under dry condition, and showed the Vogel-Tamman-Fulcher (VTF) type temperature dependence, indicating that proton transfer is cooperated by local polymer chain motion. All CL-HBP-SAs were thermally stable up to 260 deg. C, and they had suitable thermal stability as electrolyte membranes for the high-temperature fuel cells under dry condition. Fuel cell measurement using a single membrane electrode assembly cell with a cross-linked electrolyte membrane was successfully performed under non-humidified condition. It was demonstrated that applying the concept of dry polymer system to proton conduction is one possible approach toward high-temperature fuel cells.

  11. Acid-Base Interactions of Polystyrene Sulfonic Acid in Amorphous Solid Dispersions Using a Combined UV/FTIR/XPS/ssNMR Study.

    Science.gov (United States)

    Song, Yang; Zemlyanov, Dmitry; Chen, Xin; Nie, Haichen; Su, Ziyang; Fang, Ke; Yang, Xinghao; Smith, Daniel; Byrn, Stephen; Lubach, Joseph W

    2016-02-01

    This study investigates the potential drug-excipient interactions of polystyrene sulfonic acid (PSSA) and two weakly basic anticancer drugs, lapatinib (LB) and gefitinib (GB), in amorphous solid dispersions. Based on the strong acidity of the sulfonic acid functional group, PSSA was hypothesized to exhibit specific intermolecular acid-base interactions with both model basic drugs. Ultraviolet (UV) spectroscopy identified red shifts, which correlated well with the color change observed in lapatinib-PSSA solutions. Fourier transform infrared (FTIR) spectra suggest the protonation of the quinazoline nitrogen atom in both model compounds, which agrees well with data from the crystalline ditosylate salt of lapatinib. X-ray photoelectron spectroscopy (XPS) detected increases in binding energy of the basic nitrogen atoms in both lapatinib and gefitinib, strongly indicating protonation of these nitrogen atoms. (15)N solid-state NMR spectroscopy provided direct spectroscopic evidence for protonation of the quinazoline nitrogen atoms in both LB and GB, as well as the secondary amine nitrogen atom in LB and the tertiary amine nitrogen atom in GB. The observed chemical shifts in the LB-PSSA (15)N spectrum also agree very well with the lapatinib ditosylate salt where proton transfer is known. Additionally, the dissolution and physical stability behaviors of both amorphous solid dispersions were examined. PSSA was found to significantly improve the dissolution of LB and GB and effectively inhibit the crystallization of LB and GB under accelerated storage conditions due to the beneficial strong intermolecular acid-base interaction between the sulfonic acid groups and basic nitrogen centers.

  12. Benzene exposure, assessed by urinary trans,trans-muconic acid, in urban children with elevated blood lead levels

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, V.M.; Fitzwilliam, A.; Peters, H.L.; Groopman, J.D. [Johns Hopkins Univ. School of Hygiene and Public Health, Baltimore, MD (United States)] [and others

    1996-03-01

    A pilot study was performed to evaluate the feasibility of using trans, trans-muconic acid (MA) as a biomarker of environmental benzene exposure. A secondary aim was to provide data on the extent of exposure to selected toxicants in a unique population consisting of inner-city children who were already overexposed to one urban hazard, lead. Potential sources of benzene were assessed by a questionnaire. Exposure biomarkers included urinary MA and cotinine and blood lead. Mean MA was 176.6 {plus_minus} 341.7 ng/mg creatinine in the 79 children who participated. A wide range of values was found with as many as 10.1%, depending on the comparison study, above the highest levels reported in adults not exposed by occupation. Mean MA was increased in children evaluated in the afternoon compared to morning, those at or above the median for time spent playing near the street, and those studied in the first half of the investigation. MA levels were not associated with blood lead or, consistently, with either questionnaire environmental tobacco smoke (ETS) data or cotinine. As expected, the mean blood lead level was elevated (23.6 {mu}g/dl). Mean cotinine was also increased at 79.2 ng/mg creatinine. We conclude that the use of MA as a biomarker for environmental benzene exposure is feasible since it was detectable in 72% of subjects with a wide range of values present. In future studies, correlation of MA with personal air sampling in environmental exposure will be essential to fully interpret the significance of these findings. In addition, these inner-city children comprise a high risk group for exposure to environmental toxicants including ETS, lead, and probably benzene, based on questionnaire sources and its presence in ETS. 22 refs., 5 figs., 4 tabs.

  13. Preconcentration of Rare Earth Elements with 8-Hydroxyquinoline-5-sulfonic Acid Chelated Cellulose Filter Prior to Determination by Inductively Coupled Plasma Atomic Emission Spectrometry

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    8-Hydroxyquinoline-5-sulfonic acid,covalently bound to filter cellulose,was used for preconcentrating trace rare earth element(REE) ions from complex matrices and matrix separation,respectively.Multi-REE ions were preconcentrated on the column filled with 8-hydroxyquinoline-5-sulfonic acid cellulose filter and analysed by ICP-AES after being eluted with dilute HNO3.In the given pH range,alkali and alkaline earth metal ions can be separated as matrix elements;a high concentration factor is obtained and the eluates can be measured without interference.The usefulness of the method is shown by the control analyses of standard reference materials.

  14. N-Sulfonic acid poly(4-vinylpyridinum) hydrogen sulfate as a novel, efficient, and reusable solid acid catalyst for acylation under solvent-free conditions

    Institute of Scientific and Technical Information of China (English)

    Nader Ghaffari Khaligh; Parisa Ghods Ghasem-Abadi

    2014-01-01

    N-Sulfonic acid poly(4-vinylpyridinum) hydrogen sulfate has been developed as a recyclable solid acid catalyst for the acetylation of alcohols, phenols, thiols, and amines, as well as the 1,1- diacetyla-tion of aldehydes under solvent-free conditions at room temperature. The acetylated products were formed in good to excellent yields over short reaction times, and the catalyst could be readily re-covered by filtration and used several times without any discernible loss in activity. The hydrogen sulfate anion of the catalytic system was found to play a critical role in enhancing the reaction time and yield of the acetylation reaction.

  15. Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA): emerging contaminants of increasing concern in fish from Lake Varese, Italy.

    Science.gov (United States)

    Squadrone, S; Ciccotelli, V; Prearo, M; Favaro, L; Scanzio, T; Foglini, C; Abete, M C

    2015-07-01

    Perfluoroalkylated substances (PFASs) are highly fluorinated aliphatic compounds with high thermal and chemical stability, used in a range of industrial applications. Extensive screening analyses in biota samples from all over the world have shown the bioaccumulation of PFAS into higher trophic levels in the food chain. Perfluorooctane sulfonic acid (PFOS) and perfluoroctanoic acid (PFOA) are potential reproductive and developmental toxicants and are considered to be emerging endocrine disrupters. Ingestion of fish and other seafood is considered the main source of exposure of these contaminants. Here, we quantified PFOS and PFOA by LC-MS/MS in muscle samples of European perch from Lake Varese, Italy. PFOS was detected in all samples with concentrations of up to 17.2 ng g(-1). Although the reported values were lower than the recommended total daily intake (TDI) proposed by the European Food Safety Authority (EFSA), fish from Lake Varese may be a significant source of dietary PFOS exposure.

  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. Effect of intrachain sulfonic acid dopants on the solid-state charge mobility of a model radical polymer

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Holly; Wang, Yucheng; Boudouris, Bryan W., E-mail: boudouris@purdue.edu

    2015-02-27

    Radical polymers are an emerging class of non-conjugated, charge-conducting macromolecules that are capable of transporting charge through localized oxidation–reduction (redox) reactions that occur at the stable radical groups present as the pendant groups of the macromolecular chains. The chemical nature and oxidation state of these pendant radical groups are critical to the charge transporting abilities of radical polymers in the solid state. To date, however, the control of this chemistry has been limited to external oxidizing agents, and the concept of intramolecular dopants has not been explored fully. To this end, we have synthesized poly(2,2,6,6-tetramethylpiperidinyloxy methacrylate)-co-poly(vinylsulfonic acid sodium salt) (PTMA-co-PVS). Then, electron paramagnetic resonance spectroscopy and attenuated total reflectance-Fourier transform infrared spectroscopy are implemented to evaluate the exact chemical nature of the pendant groups as a function of the PVS intramolecular dopants and exposure of the materials to external oxidation reactions. We correlate these changes in pendant group chemistry to charge transport ability, and we establish that the inclusion of a moderate amount of PVS dopants can improve the solid-state hole mobility of the material. Conversely, a large amount of sulfonic acidic dopants can be detrimental to the transport of the polymer relative to the homopolymer PTMA. Therefore, refinement of pendant group chemistry and careful addition of intramolecular dopants can enhance the solid-state transport ability of a radical polymer system. These fundamental principles, in turn, provide a vital foothold by which to optimize the solid-state charge transporting ability of current and next-generation radical polymer designs. - Highlights: • Sulfonic acid groups are copolymerized within the backbone of radical polymer chain. • Addition of the sulfonic acid groups alters the pendant group oxidation state. • Exact oxidation states are

  18. Benzene carboxylic acid derivatized graphene oxide nanosheets on natural zeolites as effective adsorbents for cationic dye removal.

    Science.gov (United States)

    Yu, Yang; Murthy, Bandaru N; Shapter, Joseph G; Constantopoulos, Kristina T; Voelcker, Nicolas H; Ellis, Amanda V

    2013-09-15

    Graphene oxide (GO) nanosheets were grafted to acid-treated natural clinoptilolite-rich zeolite powders followed by a coupling reaction with a diazonium salt (4-carboxybenzenediazoniumtetrafluoroborate) to the GO surface. Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric analysis (TGA) revealed successful grafting of GO nanosheets onto the zeolite surface. The application of the adsorbents for the adsorption of rhodamine B from aqueous solutions was then demonstrated. After reaching adsorption equilibrium the maximum adsorption capacities were shown to be 50.25, 55.56 and 67.56 mg g(-1) for pristine natural zeolite, GO grafted zeolite (GO-zeolite) and benzene carboxylic acid derivatized GO-zeolite powders, respectively. The adsorption behavior was fitted to a Langmuir isotherm and shown to follow a pseudo-second-order reaction model. Further, a relationship between surface functional groups, pH and adsorption efficiency was established. Results indicate that benzene carboxylic acid derivatized GO-zeolite powders are environmentally favorable adsorbents for the removal of cationic dyes from aqueous solutions.

  19. Synthesis of highly phosphonic acid functionalized benzene-bridged periodic mesoporous organosilicas for use as efficient dye adsorbents.

    Science.gov (United States)

    Deka, Juti Rani; Liu, Chia-Ling; Wang, Tzu-Hua; Chang, Wei-Chieh; Kao, Hsien-Ming

    2014-08-15

    Periodic mesoporous organosilicas (PMOs) with benzene bridging groups in the silica wall were functionalized with a tunable content of phosphonic acid groups. These bifunctional materials were synthesized by co-condensation of two different organosilane precursors, that is, 1,4-bis(triethoxysilyl)benzene (BTEB) and sodium 3-(trihydroxysilyl)propyl methyl phosphate (SPMP), under acidic conditions using nonionic surfactant Brij-S10 as template. The materials exhibited well-ordered mesostructures and were characterized by X-ray diffraction, nitrogen sorption, TEM, TGA, FTIR, and solid-state NMR measurements. The materials thus obtained were employed as adsorbents to remove different types of dyes, for example, cationic dyes methylene blue and phenosafranine, anionic orange II, and amphoteric rhodamine B, from aqueous solutions. The materials exhibited a remarkably high adsorption capacity than activated carbon due to their ordered mesostructures, a large number of phosphonic acid groups, and high surface areas. The adsorption was mainly governed by electrostatic interaction, but also involved π-π stacking interaction as well as hydrogen bonding. The adsorption kinetics can be better fitted by the pseudo-second order model. The adsorption process was controlled by the mechanisms of external mass transfer and intraparticle diffusion. The materials retained more than 97% dye removal efficiency after use for five consecutive cycles.

  20. 荷电膜去除水中表面活性剂十二烷基苯磺酸钠研究%STUDY ON THE REMOVAL OF SURFACTANT SODIUM DODECYL BENZENE SULFONATE BY CHARGED MEMBRANE

    Institute of Scientific and Technical Information of China (English)

    张洁欣; 魏俊富; 张环

    2011-01-01

    采用自制等离子体改性聚砜荷电膜对表面活性剂十二烷基苯磺酸钠(SDBS)进行截留测试,通过改变溶液的初始SDBS质量浓度(40~400 mg· L-1)、操作压力(0.15~0.35 MPa),离子强度(NaCl质量浓度100~300 mg·L-1)以及pH(2~12)等影响因素,观察荷电膜对SDBS溶液的截留率以及通量的变化,分析作用机理.结果表明,静电斥力为主要作用力,同时伴有机械筛分作用.初始SDBS含量低时比高时截留效果好,SDBS初始质量浓度为40 mg· L-1时截留率可达85.68%;低离子强度时静电斥力发挥主要作用,截留率比高离子强度时高;压力越大,截留率越高;溶液pH接近中性时截留效果最好.%Surfactant sodium dodecyl benzene sulfonate solution was retained by the plasma modified polysulfone charged membrane. The rejection tests were at different factors including solution concentration, operating pressure (0.15~0.35 Mpa), ionic strength (concentration of NaCl 100~300 mg*L') and pH (2~12). The retention rate and flux of SDBS solution retained by charged membrane were observed. The mechanism of retention was analyzed. Experimental results revealed that electrostatic repulsion was the main force in the process. And size exclusion also existed. Solutions possessing low concentration showed better rejection effect than those having high concentration. When initial feed concentration was 40 mg'L', the retention rate could reach 85.68%. Electrostatic repulsion played an important role at low ionic strength. The retention rate at low ionic strength was higher than those at high ionic strength. The retention rate increased as the operating pressure presented high. And the rejection performed well when pH was close to neutral.

  1. Synthesis and properties of reprocessable sulfonated polyimides cross-linked via acid stimulation for use as proton exchange membranes

    Science.gov (United States)

    Zhang, Boping; Ni, Jiangpeng; Xiang, Xiongzhi; Wang, Lei; Chen, Yongming

    2017-01-01

    Cross-linked sulfonated polyimides are one of the most promising materials for proton exchange membrane (PEM) applications. However, these cross-linked membranes are difficult to reprocess because they are insoluble. In this study, a series of cross-linkable sulfonated polyimides with flexible pendant alkyl side chains containing trimethoxysilyl groups is successfully synthesized. The cross-linkable polymers are highly soluble in common solvents and can be used to prepare tough and smooth films. Before the cross-linking reaction is complete, the membranes can be reprocessed, and the recovery rate of the prepared films falls within an acceptable range. The cross-linked membranes are obtained rapidly when the cross-linkable membranes are immersed in an acid solution, yielding a cross-linking density of the gel fraction of greater than 90%. The cross-linked membranes exhibit high proton conductivities and tensile strengths under hydrous conditions. Compared with those of pristine membranes, the oxidative and hydrolytic stabilities of the cross-linked membranes are significantly higher. The CSPI-70 membrane shows considerable power density in a direct methanol fuel cell (DMFC) test. All of these results suggest that the prepared cross-linked membranes have great potential for applications in proton exchange membrane fuel cells.

  2. Green procedures for the chemoselective synthesis of acylals and their cleavage promoted by recoverable sulfonic acid based nanoporous carbon (CMK-5-SO3H)

    Indian Academy of Sciences (India)

    Daryoush Zareyee; Ehsan Mirzajanzadeh; Mohammad Ali Khalilzadeh

    2015-07-01

    A selective synthesis of gem-diacetates from the reaction of aldehydes and acetic anhydride in the presence of recyclable nanoporous solid sulfonic acid (CMK-5-SO3H) under solvent-free reaction conditions is reported. The catalyst was also found to be highly active for deprotection of resulting acylals in water.

  3. Mesomorphic structure of poly(styrene)-block-poly(4-vinylpyridine) with oligo(ethylene oxide)sulfonic acid side chains as a model for molecularly reinforced polymer electrolyte

    NARCIS (Netherlands)

    Kosonen, H; Valkama, S; Hartikainen, J; Eerikainen, H; Torkkeli, M; Jokela, K; Serimaa, R; Sundholm, F; ten Brinke, G; Ikkala, O; Eerikäinen, Hannele

    2002-01-01

    We report self-organized polymer electrolytes based on poly(styrene)-block-poly(4-vinylpyridine) (PS-block-P4VP). Liquidlike ethylene oxide (EO) oligomers with sulfonic acid end groups are bonded to the P4VP block, leading to comb-shaped supramolecules with the PS-block-P4VP backbone. Lithium perchl

  4. Enhanced bio-decolorization of 1-amino-4-bromoanthraquinone-2-sulfonic acid by Sphingomonas xenophaga with nutrient amendment

    Institute of Scientific and Technical Information of China (English)

    Hong Lu; Xiaofan Guan; Jing Wang; Jiti Zhou; Haikun Zhang

    2015-01-01

    Bacterial decolorization of anthraquinone dye intermediates is a slow process under aerobic conditions.To speed up the process,in the present study,effects of various nutrients on 1-amino-4-bromoanthraquinone-2-sulfonic acid (ABAS) decolorization by Sphingomonas xenophaga QYY were investigated.The results showed that peptone,yeast extract and casamino acid amendments promoted ABAS bio-decolorization.In particular,the addition of peptone and casamino acids could improve the decolorization activity of strain QYY.Further experiments showed that L-proline had a more significant accelerating effect on ABAS decolorization compared with other amino acids.L-Proline not only supported cell growth,but also significantly increased the decolorization activity of strain QYY.Membrane proteins of strain QYY exhibited ABAS decolorization activities in the presence of L-proline or reduced nicotinamide adenine dinucleotide,while this behavior was not observed in the presence of other amino acids.Moreover,the positive correlation between L-proline concentration and the decolorization activity of membrane proteins was observed,indicating that L-proline plays an important role in ABAS decolorization.The above findings provide us not only a novel insight into bacterial ABAS decolorization,but also an L-proline-supplemented bioaugmentation strategy for enhancing ABAS bio-decolorization.

  5. Effects of Changtai granules, a traditional compound Chinese medicine, on chronic trinitrobenzene sulfonic acid-induced colitis in rats

    Institute of Scientific and Technical Information of China (English)

    Yong-Bing Cao; Yah Wang; Yuan-Ying Jiang; Jun-Dong Zhang; Ya-Ying Diao; Lan Yan; De-Jun Wang; Xin-Ming Jia; Ping-Hui Gao; Ming-He Cheng; Zheng Xu

    2005-01-01

    AIM: To study the effects of Changtai granules (CTG), a traditional compound Chinese medicine, on chronic trinitrobenzene sulfonic acid-induced colitis in rats. METHODS: Healthy adult Sprague-Dawley (SD) rats of both sexes, weighing 250-300 g, were employed in the present study. The rat colitis models were induced by 2, 4,6-trinitrobenzene sulfonic acid (TNBS) enemas at a concentration of 100 mg/kg in 50% ethanol. The experimental animals were randomly divided into dexamethasone (DX) treatment, CTG treatment, and model control groups, which were intracolicly treated daily with DX (0.2 mg/kg), CTG at doses of 2.9, 5.7 and 11.4 g crude drug/kg, and the equal amount of saline respectively from 6 h following induction of the colitis in rats inflicted with TNBS to the end of study. A normal control group of rats treated without TNBS but saline enema was also included in the study. After 3 wk of treatment, the animals were assessed for colonal inflammatory and ulcerative responses with respect to mortality, frequency of diarrhea, histology and myeloperoxidase activity (MPO).RESULTS: The therapeutic effect of CTG on ulcerative colitis (UC) was better than DX. CTG effectively inhibited the activity of granulocytes, macrophages and monocytes in a dosedependent manner. Also it reduced MPO and formation of inflammation in colonic mucosal tissue. Furthermore, administration of CTG significantly prevented body mass loss and death, and decreased frequency of diarrhea in UC rats, when compared with the model control group rats.CONCLUSION: CTG would prove to be an ideal drug for chronic UC, and is warranted to be studied further.

  6. Study on the Retention Behavior of Aromatic Carboxylic and Sulfonic acid on a New Anion Exchange Column

    Institute of Scientific and Technical Information of China (English)

    SHI,Ya-Li; CAI,Ya-Qi; MOU,Shi-Fen

    2008-01-01

    Ion chromatography (IC) has gradually developed into a preferred method for the determination of inorganic anions. And in recent years some low molecular aliphatic acid can be also separated in the ion exchange column with the development of stationary phase. But for the determination of aromatic ionic compounds there are some problems. The aromatic anions show enhanced retention due to interaction with the π electrons of the aromatic backbone. Although the addition of an organic modifier can alleviate the difficulty, it is not the ultimate solution.IonPac AS20 column was developed using a unique polymer bonding technology and its substrate coating is aliphatic backbone. The polymer is completely free of any π electron-containing substituents in the AS20 column. In this paper, the retention behavior of aromatic carboxylic and sulfonic acid on two hydroxide-selective columns,IonPac AS11-HC, AS16, and the new column AS20 was also studied. The result showed that the retentions of ten compounds on three columns were different with each other because of their different column characteristics.Among them 4-chlorobenzene sulfonic acid, 3,5-dihydric benzoic acid and salicylic acid obviously exhibited the weakest retention on the IonPac AS20. It was showed that π-π bond function between anion and stationary phases was weakened in AS20 column because its polymer was completely free of any π electron-containing substituents.So in this paper the AS20 was selected as an analytical column to separate ten aromatic ionic compounds, fumaric acid with conjugate bond included. The retention behavior, separation of the ten compounds and effect of temperature on their retention in the anion-exchange column AS20 (2 mm) were studied. The result showed that those compounds could be separated with each other when running in gradient program and the organic modifier was unnecessary during the separation. So it is showed that AS20 column can be used as a separating column because its

  7. Organic-inorganic hybrid protonic polymeric electrolytes grafted by sulfonic acid/sulfonamide moieties

    Energy Technology Data Exchange (ETDEWEB)

    Depre, L.; Poinsignon, C.; Popall, M.

    2000-07-01

    Thin proton conducting membranes of an organic-inorganic polymer electrolyte bearing sulphonamide and sulfonic groups are prepared by sol-gel process. Polycondensation of alkoxysilanes provides the inorganic silicate backbone whereas the organic network is formed from reactive functional groups R{prime}(({minus}DH{sub 2}){sub 3}-SO{sub 3}H) and [({minus}CH{sub 2}){sub 3}-SO{sub 2}NH{sub 2}] of alkoxysilanes of R{prime}Si[OR{sub 3}] type. Proton conductivity measured in the dry and wet state under controlled Temperature and Relative Humidity increases from 10{sup {minus}4} S/cm under vacuum to 6 10{sup {minus}2} S/cm at 70 C and 96% RH. Conductivity dependence on temperature and associated conduction mechanisms are discussed in both states.

  8. 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.

  9. Solid-supported sulfonic acid-containing catalysts efficiently promoted one-pot multi-component synthesis of -acetamido carbonyl compounds

    Indian Academy of Sciences (India)

    Mohammad Ali Zolfigol; Ardeshir Khazaei; Abdolkarim Zare; Mohammad Mokhlesi; Tahereh Hekmat-Zadeh; Alireza Hasaninejad; Fatemeh Derakhshan-Panah; Ahmad Reza Moosavi-Zare; Hassan Keypour; Ahmad Ali Dehghani-Firouzabadid; Maria Merajoddin

    2012-03-01

    Silica-functionalized sulfonic acid (SFSA) and sulfuric acid-modified polyethylene glycol-6000 (PEG-OSO3H) efficiently catalysed one-pot multi-component condensation of enolizable ketones or alkyl acetoacetates with arylaldehydes, acetonitrile and acetyl chloride to afford the corresponding -acetamido ketone or ester derivatives in high to excellent yields and in relatively short reaction times. Moreover, in this work, some novel -acetamido carbonyl compounds (i.e., one complex structure) are synthesized.

  10. Application of sulfonic acid functionalized nanoporous silica (SBA-Pr-SO3H in the green one-pot synthesis of triazoloquinazolinones and benzimidazoquinazolinones

    Directory of Open Access Journals (Sweden)

    Ghodsi Mohammadi Ziarani

    2015-01-01

    Full Text Available Sulfonic acid functionalized SBA-15 (SBA-Pr-SO3H with a pore size of 6 nm was proven to be an efficient heterogeneous nanoporous solid acid catalyst in the green one-pot synthesis of triazoloquinazolinones and benzimidazoquinazolinones from the reaction of aromatic aldehydes with 3-amino-1,2,4-triazole (or 2-aminobenzimidazole and dimedone under solvent free conditions.

  11. Sulfonic acid-functionalized ordered nanoporous Na+-montmorillonite as an efficient, eco-benign, and water-tolerant nanoreactor for chemoselective oxathioacetalization of aldehydes

    Science.gov (United States)

    Shirini, Farhad; Atghia, Seyyed Vahid; Mamaghani, Manouchehr

    2013-01-01

    Sulfonic acid-functionalized ordered nanoporous sodium montmorillonite has been found to be a mild and efficient solid acid catalyst for the chemoselective protection of a variety of carbonyl compounds as oxathiolanes in good to excellent yields. The present method offers several advantages such as short reaction times, high yields, simple procedure and mild conditions. Also, the catalyst could be recycled and reused at least for five times without noticeably decreasing the catalytic activity.

  12. Synthesis & application of α-sulfonic acid fatty acid soap collector%α-磺酸基油酸皂捕收剂的应用

    Institute of Scientific and Technical Information of China (English)

    黄齐茂; 蔡坤; 王巍; 罗伍容; 潘志权; 罗惠华; 池汝安

    2012-01-01

    以大豆油酸化油为原料,经磺化、皂化等单元反应合成了α-磺酸基油酸皂浮选捕收剂,用于四川某中低品位胶磷矿的浮选试验.结果表明,该捕收剂实现了胶磷矿与白云石的有效分离,入选原矿P2O5品位23.80%,MgO质量分数6.54%;获得磷精矿P2O5品位33.88%,回收率85.37%,MgO含量1.50%.%A floatation collector, a-sulfonic acid fatty acid soap, was prepared by steps of sulfonated, saponification with soybean oil as raw material. It was used in the floatation of low-and-middle grade Sichuan phosphate ores. Test results show that the collector realizes the effective separation of phosphate and dolomite, the P2O5 content goes up to 33. 88% from 23. 80% of run-of mine with a recovery of 85. 37% , and the MgO content goes down to 1. 50% from 6. 54%.

  13. Biogeochemical dynamics of perfluorinated alkyl acids and sulfonates in the River Seine (Paris, France) under contrasting hydrological conditions

    Energy Technology Data Exchange (ETDEWEB)

    Labadie, Pierre, E-mail: p.labadie@epoc.u-bordeaux1.fr [UMR 7619 Sisyphe, CNRS/UPMC, Universite Pierre et Marie Curie, BP 105, 4 place Jussieu, 75252 Paris Cedex 05 (France); Chevreuil, Marc [Laboratoire Hydrologie et Environnement, EPHE, UMR 7619 Sisyphe, CNRS/UPMC, Universite Pierre et Marie Curie, BP 105, 4 place Jussieu, 75252 Paris Cedex 05 (France)

    2011-12-15

    The biogeochemical dynamics of 15 perfluorinated compounds (PFCs) were investigated in a heavily urbanised river (River Seine, Paris, France). The target compounds included C4-C10 sulfonates and C5-C14 acids; eleven PFCs were detected and {Sigma}PFCs ranged between 31 and 91 ng L{sup -1} (median: 47 ng L{sup -1}). The molecular pattern was dominated by the perfluoroalkyl sulfonates PFHxS and PFOS (>54% of {Sigma}PFCs), which were the only PFCs quantified in both the dissolved and particulate phases. For these PFCs, the sorbed fraction positively correlated with suspended sediment levels. Total PFC levels negatively correlated with river flow rate, which varied between 150 and 640 m{sup 3} s{sup -1}. This suggests the predominance of point sources (likely WWTP effluent discharge), but a contribution of non-point sources such as combined sewer overflow could not be excluded. The annual PFC mass flow was estimated at 500 kg, which is less than observed for other large European rivers. - Highlights: > Eleven out of fifteen perfluorinated compounds were detected in the River Seine (Paris, France). > Only PFHxS and PFOS were quantified in the particulate phase of water samples. > PFOA, PFHxS and PFOS levels negatively correlated with river flow rate (i.e. point sources were predominant). > The annual PFC mass flow in the River Seine was estimated at nearly 500 kg. - PFOA, PFOS and PFHxS levels in the River Seine negatively correlated with river flow rate, suggesting that point sources were predominant for these major PFCs.

  14. Catalytic Upgrading of bio-oil using 1-octene and 1-butanol over sulfonic acid resin catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhijun; Wang, Qingwen; Tripathi, Prabhat; Pittman, Charles U.

    2011-02-04

    Raw bio-oil from fast pyrolysis of biomass must be refined before it can be used as a transporation fuel, a petroleum refinery feed or for many other fuel uses. Raw bio-oil was upgraded with the neat model olefin, 1-octene, and with 1-octene/1-butanol mixtures over sulfonic acid resin catalysts frin 80 to 150 degrees celisus in order to simultaneously lower water content and acidity and to increase hydrophobicity and heating value. Phase separation and coke formation were key factors limiting the reaction rate during upgrading with neat 1-octene although octanols were formed by 1-octene hydration along with small amounts of octyl acetates and ethers. GC-MS analysis confirmed that olefin hydration, carboxylic acid esterification, acetal formation from aldehydes and ketones and O- and C-alkylations of phenolic compounds occurred simultaneously during upgrading with 1-octene/1-butanol mixtures. Addition of 1-butanol increased olefin conversion dramatically be reducing mass transfer restraints and serving as a cosolvent or emulsifying agent. It also reacted with carboxylic acids and aldehydes/ketones to form esters, and acetals, respectively, while also serving to stabilize bio-oil during heating. 1-Butanol addition also protected the catalysts, increasing catalyst lifetime and reducing or eliminationg coking. Upgrading sharply increased ester content and decreased the amounts of levoglucosan, polyhydric alcohols and organic acids. Upgrading lowered acidity (pH value rise from 2.5 to >3.0), removed the uppleasant ordor and increased hydrocarbon solubility. Water content decreased from 37.2% to < 7.5% dramatically and calorific value increased from 12.6 MJ kg to about 30.0 MJ kg.

  15. Thermotropic liquid crystalline polyesters derived from bis-(4-hydroxybenzoyloxy)-2-methyl-1,4-benzene and aliphatic dicarboxylic acid chlorides

    Indian Academy of Sciences (India)

    Khudbudin Mulani; Mohasin Momin; Nitin Ganjave; Nayaku Chavan

    2015-09-01

    A series of thermotropic liquid crystalline polyesters derived from bis-(4-hydroxybenzoyloxy)-2-methyl-1,4-benzene (BHBOMB) and aliphatic dicarboxylic acid chlorides were investigated. All these polyesters were synthesized by interfacial polycondensation method and characterized by differential scanning calorimetry and wide-angle X-ray diffractometer. These polyesters consist of BHBOMB as a mesogenic diol and aliphatic diacid chlorides were used as flexible spacers. The length of oligomethylene units in polymer was varied from the trimethylene to the dodecamethylene groups. The transition temperatures and thermodynamic properties were studied for all these polymers. All these polyesters were soluble in chlorinated solvents such as chloroform, dichloromethane, dichloroethane, etc. More importantly, all these polyesters exhibited very large mesophase stability.

  16. Inhibition of lactoperoxidase-catalyzed 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and tyrosine oxidation by tyrosine-containing random amino acid copolymers.

    Science.gov (United States)

    Clausen, Morten R; Skibsted, Leif H; Stagsted, Jan

    2008-09-24

    Oxidation of 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) by lactoperoxidase was found to be inhibited by tyrosine-containing random amino acid copolymers but not by tyrosine. Both electrostatic effects and polymer size were found to be important by comparison of negatively and positively charged copolymers of varying lengths, with poly(Glu, Tyr)4:1 ([E 4Y 1] approximately 40) as the strongest competitive inhibitor (EC 50 approximately 20 nM). This polymer did not form dityrosine in the presence of lactoperoxidase (LPO) and peroxide. Furthermore, incubation with tert-butyl hydroperoxide, as opposed to hydrogen peroxide, resulted in a peculiar long lag phase of the reaction between the redox intermediate compound II and [E 4Y 1] approximately 40, indicating a very tight association between enzyme and inhibitor. We propose that interactions between multiple positively charged areas on the surface of LPO and the polymer are required for optimal inhibition.

  17. Simultaneous Determination of Four Kinds of Linear Alkyl Benzene Sulfonates by Solid Phase Extraction/High Performance Liquid Chromatography%固相萃取/高效液相色谱法同时测定水中4种直链烷基苯磺酸钠

    Institute of Scientific and Technical Information of China (English)

    周围; 解迎双; 王波; 贾松涛; 牛洪亮

    2011-01-01

    A solid phase extraction coupled with high performance liquid chromatographic (SPE/HPLC) method was established for the determination of 4 kinds of sodium n-alkyl benzene sulfonates in water. The samples were refrigerated and centrifuged, then purified and enriched with MAX complex anion exchange column. Four sodium n-alkyl benzene sulfonates were successfully separated by HPLC using acetonitrile - 100 mmol/L ammonium acetate (73 : 27, by volume) as mobile phase with a flow rate of 1 mL/min, column temperature of 30 ℃, detection wavelength of 225 nm and injection volume of 10 μL. Under the optimal conditions, the calibration curves were linear in the range of 10 -50 mg/L for sodium undecylbenzene sulfonte and sodium N-tridecylbenzene sulfonate with detection limits of 10 mg/L, and 5 -25 mg/L for sodium dodecylbenzene sulphonate and sodium tetradecylbenzene sulfonate with detection limits of 5 mg/L. The spiked recoveries were in the range of 86% -98% with relative standard deviations(RSDs) of 2. 9% -7.4%.%建立了水中4种直链烷基苯磺酸钠的固相萃取/高效液相色谱的测定方法.样品经高速冷冻离心,用MAX复合阴离子交换小柱净化富集后直接进样.在以乙腈-100 mmol/L乙酸铵(体积比73:27)为流动相,流速1 mL/min,柱温30 ℃,检测波长225 nm,进样体积10 μL的条件下,4种直链烷基苯磺酸钠得到很好的分离.在优化实验条件下,十一烷基苯磺酸钠与十三烷基苯磺酸钠的线性范围为10~50 mg/L,检出限为10 mg/L,十二烷基苯磺酸钠与十四烷基苯磺酸钠的线性范围为5~25 mg/L,检出限为5 mg/L;加标回收率为86%~98%;相对标准偏差为2.9%~7.4%.

  18. PENGARUH SUHU DAN LAMA PROSES SULFONASI DALAM PROSES PRODUKSI METHYL ESTER SULFONIC ACID (MESA MENGGUNAKAN SINGLE TUBE FALLING FILM REACTOR (STFR

    Directory of Open Access Journals (Sweden)

    Siti Mujdalipah

    2013-03-01

    Full Text Available Effects of Temperature and Sulfonation Time on Methyl Ester Sulfonic Acid (MESA Production Process usingSingle Tube Falling Film Reactor (STFR Siti Mujdalipah, Erliza Hambali, Ani Suryani, Edi Zulchaidir ABSTRAK Methyl Ester Sulfonic Acid (MESA merupakan produk antara dari surfaktan Metil Ester Sulfonat (MES. MESmemiliki beragam aplikasi dalam produk personal care, pencuci dan pembersih, dan untuk Enhanced Oil Recovery(EOR. Proses produksi MESA menggunakan gas SO3 dalam Single Tube Falling Film Reactor (STFR merupakanteknologi yang umum digunakan. Kajian ini bertujuan untuk mendapatkan kondisi proses sulfonasi metil ester oleinterbaik menggunakan gas SO3 dalam STFR. Kajian dilakukan dalam tiga tahap, yaitu tahap penelitian, tahap analisis,dan tahap pengolahan data. Tahap produksi MESA terdiri dari pembuatan metil ester (ME dari olein minyak sawit dankajian pengaruh suhu dan lama proses sulfonasi. Tahap analisis meliputi analisis sifat Þ siko kimia olein minyak sawit,analisa sifat Þ siko kimia ME olein sawit, dan analisis sifat Þ siko kimia MESA olein sawit. Kajian pengaruh suhu danlama proses sulfonasi terhadap proses sulfonasi metil ester olein terdiri dari suhu 70, 90, dan 110 oC dan lama prosessulfonasi 30, 60, dan 90 menit. Analisis varian pada !=0,01 menunjukan bahwa lama proses sulfonasi berpengaruh nyataterhadap kadar bahan aktif. Analisis varian pada !=0,01 juga menunjukan bahwa lama proses sulfonasi berpengaruhnyata terhadap nilai pH, bilangan asam, bilangan iod, dan kemampuan MESA dalam menurunkan tegangan antarmuka(IFT, Interfacial Tension antara air formasi dan minyak bumi. Proses sulfonasi terbaik dicapai pada suhu sulfonasi 90oCdan lama proses sulfonasi 90 menit. Kondisi proses sulfonasi terbaik dapat menghasilkan MESA dengan karakteristikkadar bahan aktif 31,44%, pH 2,66, bilangan asam 24,88 ml NaOH/g sampel, bilangan iod 11,95 mg I/g sampel, danmemiliki kemampuan menurunkan IFT antara air formasi dan minyak bumi dari 30 dyne

  19. Covalently anchored sulfonic acid on silica gel (SiO2-R-SO3H) as an efficient and reusable heterogeneous catalyst for the one-pot synthesis of 1,8-dioxooctahydroxanthenes under solvent-free conditions

    Institute of Scientific and Technical Information of China (English)

    Gholam Hossein Mahdavinia; Mohammad A.Bigdeli; Yaser Saeidi Hayeniaz

    2009-01-01

    A highly efficient one-pot synthesis of 1,8-dioxooctahydroxanthenes under solvent-free conditions catalyzed by sulfonic acid covalently anchored onto the surface of silica gel is reported.All types of aldehydes,including aromatic,unsaturated,and heterocyclic,are used.The silica gel/sulfonic acid catalyst (SiO2-R-SO3H) is completely heterogeneous and can be recycled.

  20. One step graft copolymerization of acrylic acid and sodium styrene sulfonate onto high-density polyethylene film by preirradiation method

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    High-density polyethylene (HDPE) films were irradiated by 60Co gamma ray with a dose of 100 kGy in air and then immersed in aqueous solution of acrylic acid (AA) and sodium styrene sulfonate (SSS) at different temperature. The effects of grafting conditions such as temperature, reaction time, Mohr's salt concentration, and total concentration of monomer on grafting yield were studied. Both grafting yield of AA and SSS onto HDPE respectively increases with total concentration of monomers. The highest grafting yield was observed at 3 mol/L monomers where the grafted PE swelled to the largest extent in the monomers mixture. The grafting yield increases with reaction time and then levels off. At higher temperature, the grafting yield decreases with Mohr's salt concentration, but increases at low temperature when Mohr's salt concentration is 0.083%. Which can be interpreted that in the presence of Fe2+ diperoxides and hydroperoxides may decompose at low temperature to form radical which can initiate the grafting. The physical and chemical properties of grafting films were also investigated.

  1. Construction and Study of Hetreojunction Solar Cell Based on Dodecylbenzene Sulfonic Acid-Doped Polyaniline/n-Si

    Directory of Open Access Journals (Sweden)

    I. Morsi

    2012-01-01

    Full Text Available Polyaniline/n-type Si heterojunctions solar cell are fabricated by spin coating of soluble dodecylbenzene sulfonic acid (DBSA-doped polyaniline onto n-type Si substrate. The electrical characterization of the Al/n-type Si/polyaniline/Au (Ag structure was investigated by using current-voltage (I-V, capacitance-voltage (C-V, and impedance spectroscopy under darkness and illumination. The photovoltaic cell parameters, that is, open-circuit voltage (oc, short-circuit current density (sc, fill factor (FF, and energy conversion efficiency (η were calculated. The highest sc, oc, and efficiency of these heterojunctions obtained using PANI-DBSA as a window layer (wideband gap and Au as front contact are 1.8 mA/cm2, 0.436 V, and 0.13%, respectively. From Mott-Schottky plots, it was found that order of charge carrier concentrations is 3.5×1014 and 1.0×1015/cm3 for the heterojunctions using Au as front contact under darknessness and illumination, respectively. Impedance study of this type of solar cell showed that the shunt resistance and series resistance decreased under illumination.

  2. Exposure to perfluorooctane sulfonic acid (PFOS) adversely affects the life-cycle of the damselfly Enallagma cyathigerum

    Energy Technology Data Exchange (ETDEWEB)

    Bots, Jessica, E-mail: Jessica.bots@ua.ac.b [Evolutionary Ecology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerpen (Belgium); De Bruyn, Luc, E-mail: luc.debruyn@ua.ac.b [Evolutionary Ecology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerpen (Belgium); Research Institute for Nature and Forest (INBO), Kliniekstraat 25, 1070 Brussels (Belgium); Snijkers, Tom, E-mail: tomsnijkers@gmail.co [Evolutionary Ecology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerpen (Belgium); Van den Branden, Bert, E-mail: bvandenbranden@gmail.co [Department PIH Environment, University College West Flanders (HOWEST), Graaf K. 11 de Goedelaan 5, B-8500 Kortrijk (Belgium); Van Gossum, Hans, E-mail: hans.vangossum@ua.ac.b [Evolutionary Ecology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerpen (Belgium)

    2010-03-15

    We evaluated whether life-time exposure to PFOS affects egg development, hatching, larval development, survival, metamorphosis and body mass of Enallagma cyathigerum (Insecta: Odonata). Eggs and larvae were exposed to five concentrations ranging from 0 to 10 000 mug/L. Our results show reduced egg hatching success, slower larval development, greater larval mortality, and decreased metamorphosis success with increasing PFOS concentration. PFOS had no effect on egg developmental time and hatching or on mass of adults. Eggs were the least sensitive stage (NOEC = 10 000 mug/L). Larval NOEC values were 1000 times smaller (10 mug/L). Successful metamorphosis was the most sensitive response trait studied (NOEC < 10 mug/L). The NOEC value suggests that E. cyathigerum is amongst the most sensitive freshwater organisms tested. NOEC for metamorphosis is less than 10-times greater than the ordinary reported environmental concentrations in freshwater, but is more than 200-times smaller than the greatest concentrations measured after accidental releases. - Long-term laboratory exposure to perfluorooctane sulfonic acid reduces survival and interferes with metamorphosis of Enallagma cyathigerum (Insecta: Odonata).

  3. Comparison of electronic transport properties of soluble polypyrrole and soluble polyaniline doped with dodecylbenzene-sulfonic acid

    Energy Technology Data Exchange (ETDEWEB)

    Aleshin, A.N.; Lee, K. [California Univ., Santa Barbara, CA (United States). Inst. for Polymers and Organic Solids; Lee, J.Y.; Kim, D.Y.; Kim, C.Y. [Polymer Materials Laboratory, Korea Institute of Science and Technology, Seoul 130-650 (Korea, Republic of)

    1999-01-29

    The temperature dependences of the conductivity of soluble polypyrrole (PPy) and soluble polyaniline (PANI) films doped with dodecylbenzene-sulfonic acid (DBSA) have been studied. The room temperature conductivities of samples were 1-8 and 95-100 S/cm, with resistivity ratio {rho}{sub r}={rho}(20 K)/{rho}(300 K){proportional_to}10{sup 4} and {rho}{sub r}={rho}(1.4 K)/{rho}(300 K){proportional_to}32 for PPy-DBSA and PANI-DBSA, respectively. At low temperatures, the temperature dependence follows the {sigma}(T)={sigma}{sub 0}exp[-(T{sub 0}/T){sup m}] law, which has been explained within the framework of granular metals model (m=0.5) for PPy-DBSA and Mott`s variable range hopping model (m=0.25) for PANI-DBSA. The magnetoresistance of PANI-DBSA is positive and follows H{sup 2} and H{sup 1/3} dependencies at low and high magnetic fields, respectively; the magnitude of the magnetoresistance is strongly temperature dependent. (orig.) 35 refs.

  4. p-toluene sulfonic acid doped polyaniline carbon nanotube composites: synthesis via different routes and modified properties

    Directory of Open Access Journals (Sweden)

    ASHOK K. SHARMA

    2013-04-01

    Full Text Available Composites of polyaniline and carbon nanotube (CNT were prepared by in-situ chemical polymerization method using various aniline concentrations in the initial polymerization solution with p-toluene sulfonic acid (PTS as secondary dopant and mechanical mixing of the PANI and CNT using different weight ratios of PANI and CNTs. The structural characterizations of the composites were done by Fourier transform infrared (FTIR and Ultra violet visible spectroscopy (UV-Visible. Scanning electron microscopy (SEM was used to characterize the surface morphology of the composites. It was found that the composites prepared by in-situ chemical polymerization had smoother surface morphology in comparison to the composites obtained by mechanical mixing. The capacitive studies reveal that the in-situ composite has synergistic effect and the specific capacitance of the composite calculated from cyclic voltammogram (CV was 385.1 F/g. Thermal studies indicate that the composites are stable as compared to PANI alone showing that the CNT contributes towards thermal stability in the PANI-CNT composites.

  5. Study of polyaniline doped with trifluoromethane sulfonic acid in gas-diffusion electrodes for proton-exchange membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Gharibi, Hussein; Zhiani, Mohammad; Kheirmand, Mehdi; Kakaei, Karim [Department of Physical Chemistry, Faculty of Science, Tarbiat Modarres University, P.O. Box 14115-175, Tehran (Iran); Entezami, Ali Akbar [Faculty of Chemistry, Tabriz University, Tabriz (Iran); Mirzaie, Rasol Abdullah [Department of Chemistry, Faculty of Science, Shahid Rajaee University, Tehran (Iran)

    2006-04-21

    Polytetrafluoroethylene (PTFE)-bonded gas-diffusion electrodes (GDEs), modified with polyaniline as an electron and proton conductor in the catalyst layer, are prepared and evaluated for use in proton-exchange membrane fuel cells (PEMFCs). Polyaniline is coated on the GDE by electropolymerization of aniline and trifluoromethane sulfonic acid as the proton-conductive monomer. The electrodes are characterized by cyclic voltammetry, current-potential measurements, electrochemical impedance spectroscopy, and chronoamperometry. The polyaniline is found to be homogenously dispersed in the catalyst layer, making it a good candidate proton and electron conductor. Use of polyaniline instead of Nafion in the catalyst layer, increases the utility of the electrocatalyst by 18%. The results are consistent with the presence of polyaniline as a conductive polymer in the reaction layer reducing the polarization resistance of the electrode in comparison with that of a corresponding electrode containing Nafion. Thus, the present results indicate that PEMFCs using polyaniline-containing electrocatalysts should give superior performance to those using catalysts containing traditional ionomers. (author)

  6. Bioaccumulation of perfluoroalkyl acids including the isomers of perfluorooctane sulfonate in carp (Cyprinus carpio) in a sediment/water microcosm.

    Science.gov (United States)

    Fang, Shuhong; Zhang, Yifeng; Zhao, Shuyan; Qiang, Liwen; Chen, Meng; Zhu, Lingyan

    2016-12-01

    Carp (Cyprinus carpio) were exposed to perfluoroalkyl acids (PFAAs) including perfluorooctane sulfonate (PFOS) isomers in an artificially contaminated sediment/water microcosm. The uptake constant of PFAAs increased with increasing carbon chain length, whereas the elimination coefficient displayed the opposite trend, suggesting that carbon chain length plays an important role in the bioaccumulation of PFAAs. When the contribution of suspended particulate matter was taken into account, the bioaccumulation factors (BAFs) became lower (3.61-600 L/kg) compared with BAFs derived from only considering the absorption from free PFAAs in water (3.85-97000 L/kg). The results indicate that suspended particulate matter in water constitutes an important source of exposure for aquatic organisms to long-chain PFAAs. Linear (n-)PFOS was preferentially accumulated compared with branched isomers in carp. Among the branched isomers, 1m-PFOS displayed the greatest bioaccumulation, whereas m2 -PFOS had the lowest. Linear PFOS displayed greater partitioning ability from blood to other tissues over branched PFOS (br-PFOS) isomers, leading to a relatively lower n-PFOS proportion in blood. In summary, suspended particulate matter made a contribution to the accumulation of long-chain PFAAs in aquatic organisms, and n-PFOS was preferentially accumulated compared with br-PFOS isomers. Environ Toxicol Chem 2016;35:3005-3013. © 2016 SETAC.

  7. A novel voltammetric sensor for citalopram based on multiwall carbon nanotube/(poly(p-aminobenzene sulfonic acid)/β-cyclodextrin)

    Energy Technology Data Exchange (ETDEWEB)

    Gholivand, Mohammad-Bagher, E-mail: mbgholivand2013@gmail.com; Akbari, Arezoo

    2016-05-01

    Multi-walled carbon nanotube (MWCNTS) coated with poly p-aminobenzene sulfonic acid/β-cyclodextrin (p-ABSA/β-CD) film was used as an effective strategy for modification of the surface of glassy carbon electrode (GCE). Electrochemical study and determination of citalopram (CT) were investigated at the p (p-ABSA)/β-CD/MWCNT/GC using cyclic and differential pulse anodic stripping voltammetric techniques. The results indicate that the p (p-ABSA)/β-CD/MWCNT/GC significantly enhanced the oxidation peak current of CT. The modified electrode was characterized by electrochemical impedance spectroscopy (EIS), scanning electron microscopy(SEM) and cyclic voltammetry (CV).The fabricated electrochemical sensor exhibits a fast and reversible linear response toward CT within the concentration ranges of 90 nM–1 μM, 1–11 μM and 11–100 μM with correlation coefficients greater than 0.99 and detection limit of 44 nM. The resulting functionalized polymer film features interesting electrochemical properties such good recovery, reproducibility and selectivity toward CT. The applicability of the proposed sensor was tested by determination of CT in pharmaceutical combinations and human body fluids. - Highlights: • A novel voltammetric sensor for CT based on p (p-ABSA)/β-CD/MWCNT/GC • Electrochemical study of CT was investigated using CV and DPASV techniques. • This sensor is made easy with good sensitivity and reproducibility. • The method was developed in real sample in the presence of matrix effect.

  8. Spectrophotometric determination of procaine hydrochloride in pharmaceutical products using 1,2-naphthoquinone-4-sulfonic acid as the chromogenic reagent

    Science.gov (United States)

    Xu, Li Xiao; Shen, Yun Xiu; Wang, Huai You; Jiang, Ji Gang; Xiao, Yan

    2003-11-01

    Spectrophotometric determination of procaine hydrochloride is described. The procaine hydrochloride reacts with 1,2-naphthoquinone-4-sulfonic acid in pH 3.60 buffer solution to form a salmon pink compound, and its maximum absorption wavelength is at 484 nm, ɛ 484=5.22×10 3.The absorbance for procaine hydrochloride from 0.30 to 100 μg ml -1 obeys Beer's law. The linear regression equation of the calibration graph is C=19.23A-0.03, with a linear regression correlative coefficient is 0.9996, the detection limit is 0.28 μg ml -1; recovery is from 98.0 to 105.2%. Effects of pH, surfactant, organic solvent, foreign ions, and standing time on the determination of procaine hydrochloride have been examined. This method is rapid and simple, and can be used for the determination of procaine hydrochloride in injection solution of procaine hydrochloride. The results obtained by this method agreed with those by the official method (dead-stop titration).

  9. Benzocaine complexation with p-sulfonic acid calix[n]arene: experimental ((1) H-NMR) and theoretical approaches.

    Science.gov (United States)

    Arantes, Lucas M; Varejão, Eduardo V V; Pelizzaro-Rocha, Karin J; Cereda, Cíntia M S; de Paula, Eneida; Lourenço, Maicon P; Duarte, Hélio A; Fernandes, Sergio A

    2014-05-01

    The aim of this work was to study the interaction between the local anesthetic benzocaine and p-sulfonic acid calix[n]arenes using NMR and theoretical calculations and to assess the effects of complexation on cytotoxicity of benzocaine. The architectures of the complexes were proposed according to (1) H NMR data (Job plot, binding constants, and ROESY) indicating details on the insertion of benzocaine in the cavity of the calix[n]arenes. The proposed inclusion compounds were optimized using the PM3 semiempirical method, and the electronic plus nuclear repulsion energy contributions were performed at the DFT level using the PBE exchange/correlation functional and the 6-311G(d) basis set. The remarkable agreement between experimental and theoretical approaches adds support to their use in the structural characterization of the inclusion complexes. In vitro cytotoxic tests showed that complexation intensifies the intrinsic toxicity of benzocaine, possibly by increasing the water solubility of the anesthetic and favoring its partitioning inside of biomembranes.

  10. Astragaloside IV ameliorates 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis implicating regulation of energy metabolism.

    Science.gov (United States)

    Jiang, Xu-Guang; Sun, Kai; Liu, Yu-Ying; Yan, Li; Wang, Ming-Xia; Fan, Jing-Yu; Mu, Hong-Na; Li, Chong; Chen, Yuan-Yuan; Wang, Chuan-She; Han, Jing-Yan

    2017-02-02

    Dysfunction of energy metabolism is involved in inflammatory bowel disease (IBD). This study was designed to investigate the potential of astragaloside IV (ASIV), an active ingredient of Radix Astragalus, to ameliorate colonic mucosal injury, with focusing on the implication of energy restoration in the underlying mechanism. Experimental colitis model was established in rats by injecting 2,4,6-trinitrobenzene sulfonic acid (TNBS) through anus. After 24 hours, ASIV was administrated once daily by gavage for 6 days. On day 1 and day 7, colon tissue was collected for macroscopic and histological examination, ELISA, Western blot and immunohistochemical analysis. TNBS impaired colonic mucosa with an injured epithelial architecture, increased inflammatory cell infiltration, and decreased colonic blood flow. Lgr5 positive cell number in crypt and β-catenin nuclear translocation were down-regulated by TNBS treatment. TNBS induced epithelial F-actin disruption and junctional protein degradation. Furthermore, adenosine triphosphate (ATP) content and ATP synthase subunit β expression in the colon tissue were significantly decreased after TNBS stimulation. All of the aforementioned alterations were relieved by ASIV post-treatment. The present study revealed that ASIV promoted mucosal healing process in TNBS-induced colitis, which was most likely attributed to regulating energy metabolism.

  11. 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.

  12. Graft (partially carboxymethylated guar gum-g-poly vinyl sulfonic acid) copolymer: from synthesis to applications.

    Science.gov (United States)

    Yadav, Mithilesh; Srivastav, Abhishek; Verma, Shiv Kumar; Behari, Kunj

    2013-09-12

    The aim of the paper is to study the physico-chemical phenomenon of synthesized graft copolymer (carboxymethylated guar gum-g-vinylsulfonic acid). The reaction optimum conditions for grafting has also been determined by studying the effect of vinylsulfonic acid, hydrogen ion, peroxymonosulphate, glycolic acid concentration and carboxymethylated guar gum along with time and temperature. Experimental results show that maximum grafting has been obtained at 1.8 g dm(-3) concentration of partially carboxymethylated guar gum and 5.3 × 10(-2) mol dm(-3) concentration of vinylsulfonic acid. It has been observed that grafting ratio, add on, conversion, efficiency increase up to 4.0 × 10(-3) mol dm(-3) of hydrogen ion, 4 × 10(-3) mol dm(-3) of glycolic acid, 14 × 10(-3) mol dm(-3) of peroxymonosulphate and 35 °C of temperature. Grafted copolymer has been characterized by FTIR spectroscopy and thermogravimetric analysis. Water swelling, flocculating, metal ion uptake and resistance to biodegradability properties of partially carboxymethylated guar gum-g-vinylsulfonic acid have been determined.

  13. Morphological control of layered double hydroxide through a biomimetic approach using carboxylic and sulfonic acids

    Directory of Open Access Journals (Sweden)

    Taishi Yokoi

    2015-09-01

    Full Text Available Layered double hydroxides (LDHs have intercalation properties and are used in various applications. The performances of the LDH materials can be improved by controlling crystal morphology. Morphology of inorganic crystals is controlled by organic molecules in biomineralization. Inspired by biomineralization, we investigated the effect of the addition of mono, di and triacids as morphological control agents on crystal morphology of LDH synthesized by the homogeneous precipitation method. Morphology of LDH was changed from hexagonal plate to stacked disc by addition of monoacids, namely acetic acid and methanesulfonic acid, in the reaction solution. Flower-shaped LDH crystals were formed in the presence of diacids and a triacid, namely succinic acid, 1,2-ethanedisulfonic acid and 1,2,3-propanetricarboxylic acid. We found that the morphology of the LDH crystals was controlled by the number of functional group on the morphological control agent rather than the type of functional group. These findings can contribute for the development of novel and functional LDH materials with precisely controlled morphology.

  14. 无机阴离子对TiO2-膨润土紫外光降解SDBS的影响%Effect of Inorganic Anion on Degradation of Sodium Dodecyl Benzene Sulfonate by TiO2-bentonite

    Institute of Scientific and Technical Information of China (English)

    温淑瑶; 马占青; 马敏立

    2012-01-01

    Photodegradation of sodium dodecyl benzene sulfonate (SDBS) by TiO2-bentonite is efficient, and the inorganic anions such as Cl-, SO42-, NO3-, HCO3-, H2PO4- which usually exist in water have an effect on photodegradation efficiency of SDBS by TiO2-bentonite. 36 mmol/L sodium salt of these inorganic anions was input into SDBS aqueous solution respectively,and the solutions were irradiated for 2 h with ultraviolet lamp. The difference of photodegradation results with or without the input of inorganic anions in the solution was compared. Results showed that effect of inorganic anion such as Cl-, SO42-, NO3-,HCO3-, H2PO4- on degradation of SDBS by TiO2-bentonite existed. Among which the effect of HCO3- on degradation was the most obvious, followed by H2PO-4 , NO3- , SO42-, Cl- The concentration of SDBS solutions with input of HCO3- , H2PO4- , NO3- ,SO42-, Cl- increased by 2.63, 1.63, 0.73, 0.52 and 0.46 times respectively within 2 h than that without input of the inorganic anions, which mainly depends on the competitions of surface active position between inorganic anions and organic molecules,appearance of high polarity environment near surface of catalyst particle and change of pH of solutions. Effect of inorganic anion on COD of aqueous solutions was different, within 2 h COD of aqueous solutions which had been input Cl-, SO42-,NO3- , HCO3- , HZPO4- , increased 6.62, 0.26, 0.03, 0.29 and 0.45 times respectively than that hadn't been put into.%TiO2-膨润土光催化降解水溶液中阴离子表面活性剂十二烷基苯磺酸钠(SDBS)的效率较高,Cl-、SO42-、NO3-、HC3-、H2PO4-是水体中常见的阴离子,这些阴离子对降解效果的影响直接影响该技术的实际应用.分别投加36 mmol/L上述阴离子的钠盐到SDBS水溶液中,紫外光照射溶液2h,比较投加与不投加的SDBS去除效果差异,结果表明:(1)水溶液中上述阴离子对TiO2-膨润土降解SDBS的效果都有不利影响,其中HCO3影响最大,其次是H2PO4_,

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-12-15

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

  16. Degradation and mineralization of organic UV absorber compound 2-phenylbenzimidazole-5-sulfonic acid (PBSA) using UV-254nm/H2O2.

    Science.gov (United States)

    Abdelraheem, Wael H M; He, Xuexiang; Duan, Xiaodi; Dionysiou, Dionysios D

    2015-01-23

    Various studies have revealed the non-biodegradable and endocrine disrupting properties of sulfonated organic UV absorbers, directing people's attention toward their risks on ecological and human health and hence their removal from water. In this study, UV-254nm/H2O2 advanced oxidation process (AOP) was investigated for degrading a model UV absorber compound 2-phenylbenzimidazole-5-sulfonic acid (PBSA) and a structurally similar compound 1H-benzimidazole-2-sulfonic acid (BSA), with a specific focus on their mineralization. At 4.0mM [H2O2]0, a complete removal of 40.0μM parent PBSA and 25% decrease in TOC were achieved with 190min of UV irradiation; SO4(2-) was formed and reached its maximum level while the release of nitrogen as NH4(+) was much lower (around 50%) at 190min. Sulfate removal was strongly enhanced by increasing [H2O2]0 in the range of 0-4.0mM, with slight inhibition in 4.0-12.0mM. Faster and earlier ammonia formation was observed at higher [H2O2]0. The presence of Br(-) slowed down the degradation and mineralization of both compounds while a negligible effect on the degradation was observed in the presence of Cl(-). Our study provides important technical and fundamental results on the HO based degradation and mineralization of SO3H and N-containing UV absorber compounds.

  17. Experimental study of the removal of copper ions using hydrogels of xanthan, 2-acrylamido-2-methyl-1-propane sulfonic acid, montmorillonite: Kinetic and equilibrium study.

    Science.gov (United States)

    Aflaki Jalali, Marzieh; Dadvand Koohi, Ahmad; Sheykhan, Mehdi

    2016-05-20

    In this paper, removal of copper ions from aqueous solution using novel xanthan gum (XG) hydrogel, xanthan gum-graft-2-acrylamido-2-methyl-1-propane sulfonic acid (XG-g-P(AMPS)) hydrogel and xanthan gum-graft-2-acrylamido-2-methyl-1-propane sulfonic acid/montmorillonite (XG-g-P(AMPS)/MMT) hydrogel composite were studied. The structure and morphologies of the xanthan-based hydrogels were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). Adsorbents comprised a porous crosslink structure with side chains that carried carboxyl, hydroxyl and sulfonate. Maximum adsorption was observed in the pH=5.2, initial concentrations of Cu(2+)=321.8 mg/L, Temperature=45 °C, contact time=5 h with 0.2 g/50 mL of the hydrogels. Adsorption process was found to follow Langmuir isotherm model with maximum adsorption capacity of 24.57, 39.06 and 29.49 mg/g for the XG, XG-g-P(AMPS) and XG-g-P(AMPS)/MMT, respectively. Adsorption kinetics data fitted well with pseudo second order model. The negative ΔG° values and the positive ΔS° confirmed that the adsorption was a spontaneous process. The positive ΔH° values suggested that the adsorption was endothermic in nature.

  18. Synthesis, Antibacterial and Antitubercular Activities of Some 5H-Thiazolo[3,2-a]pyrimidin-5-ones and Sulfonic Acid Derivatives

    Directory of Open Access Journals (Sweden)

    Dong Cai

    2015-09-01

    Full Text Available A series of 5H-thiazolo[3,2-a]pyrimidin-5-ones were synthesized by the cyclization reactions of S-alkylated derivatives in concentrated H2SO4. Upon treatment of S-alkylated derivatives at different temperatures, intramolecular cyclization to 7-(substituted phenylamino-5H-thiazolo[3,2-a]pyrimidin-5-ones or sulfonation of cyclized products to sulfonic acid derivatives occurred. The structures of the target compounds were confirmed by IR, 1H-NMR, 13C-NMR and HRMS studies. The compounds were evaluated for their preliminary in vitro antibacterial activity against some Gram-positive and Gram-negative bacteria and screened for antitubercular activity against Mycobacterium tuberculosis by the broth dilution assay method. Some compounds showed good antibacterial and antitubercular activities.

  19. 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

    of decreasing hydrophobicity. This is indicated by the initial decrease and then increase in the value of Keq. with the increasing strength of the acid treatment. The corresponding carbon - ionomer composite also showed varying thermal stability depending on Nafion orientation. The specific maximum surface...... 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...

  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. Doping effect of dodecyl benzene sulphonic acid in poly(3-hexylthiophene)-P3HT-films

    Science.gov (United States)

    Alveroglu, Esra

    2015-04-01

    We demonstrated that how dodecyl benzene sulphonic acid (DBSA) as a small-molecular dopant, affects the spectroscopic, electronic and structural properties of poly(3-hexylthiophene) (P3HT). The DBSA volume ratio was varied from 0.001 μL to 30 μL per 1 mL P3HT solvent in p-xylene. DBSA doping reaction was confirmed by the emerging huge absorption peak at the wavelength of ∼800 nm while the ionization potential and nanostructure of P3HT films were highly affected. Additionally, conductivity of P3HT films increased nearly 1000 times at 30 μL DBSA. The crystallinity, as well as the conductivity and the UV-Vis absorption changed with the presence of P3HT. P3HT grain sized crystals seems to be disturbed by the addition of DBSA, but still remained even more DBSA was introduced. DBSA doping has interesting properties when incorporated in OFTs, OPVs and bioelectronics applications, so addition of DBSA can open new pathways for structural, spectroscopic and electronic control of organic semiconductor's blends.

  2. Study of poly (acrylamide-co-2-acrylamido-2-methylpropane sulfonic acid) hydrogel using gamma radiation initiation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, C.; Easteal, A.J. [The University of Auckland, Auckland (New Zealand). Department of Chemistry

    1998-12-31

    Full text: Poly (acrylamide-co-2-acrylamido-2-methylpropane sulfonic acid ) (PAAM-co-AMPS) polyelectrolyte hydrogels were formed by using {gamma}-radiation to initiate polymerization and cross-linking. The dependence of chain growth and cross-linking of liquid-like gel on absorbed dose was observed by viscosity measurement. It was found that the viscosity of liquid-like gel increased non-linearly with increasing radiation dose. Crosslinking took place at about 2,300 Gy. It was noted that an ageing effect occurred, such that the viscosity of liquid-like gels decreased significantly on standing. X-ray diffraction revealed that after dehydration the dried gels were amorphous, suggesting that radiation polymerization occurs by random initiation and propagation. Differential scanning calorimetry (DSC) indicated a clear distinction between the thermal behaviour of the homopolymer gels formed by irradiation, and the behaviour of the copolymer gels. PAAM-co-AMPS gels have enhanced thermal stability in comparison to PAAM and PAMPS. The melting points of water in the gels initially increase with increasing dose, and decrease slightly at very high radiation dose. Those trends can be explained by the variation in the numbers of solute molecules or ions in the gels with absorbed dose. Melting points of water in gels can be used for observation of the polymerization process associated with irradiation. Copolymer composition (expressed by either f{sub 1} (AAM molal fraction ) or f{sub 2} (AMPS molal fraction) ) associated with radiation dose was determined by both elemental analysis and FTIR. Both methods show that f{sub 1} increases to a maximum with increasing dose, and subsequently decreases. It is concluded that PAAM-co-AMPS hydrogels were synthesised successfully by gamma radiation initiation, and that copolymer compositions are dependent on radiation dose

  3. The enhancement of fluorescence quantum yields of anilino naphthalene sulfonic acids by inclusion of various cyclodextrins and cucurbit[7]uril

    Science.gov (United States)

    Sueishi, Yoshimi; Fujita, Tomonori; Nakatani, Shinichiro; Inazumi, Naoya; Osawa, Yoshihiro

    2013-10-01

    The association constants (K) for the inclusion complexation of four kinds of cyclodextrins (CDs (β- and γ-), 2,6-di-O-methylated β-CD, and 2,3,6-tri-O-methylated β-CD) and cucurbit[7]uril (CB[7]) with 1,8- and 2,6-anilinonaphthalene sulfonic acids (ANSs) were determined from fluorescence spectra enhanced by inclusion. Various CDs and CB[7] form stable 1:1 inclusion complexes with 1,8- and 2,6-ANSs: K = 80-11 700 M-1 for 2,6-ANS and 50-195 M-1 for 1,8-ANS. The high stability of the inclusion complexes of 2,6-ANS with CB[7] and 2,6-di-O-methylated β-CD is shown. Further, we determined the fluorescence quantum yields (Φ values) for the inclusion complexes of ANSs by using a fluorescence spectrophotometer equipped with a half-moon unit. The Φ values of 1,8- and 2,6-ANSs were largely enhanced by the inclusion of methylated β-CDs and did not correlate with the degree of stability (K) of the inclusion complexes. We characterized the structures of the inclusion complexes by 2D ROESY-NMR measurements. In addition, the microenvironmental polarity inside the hydrophobic CD and CB[7] cavities was evaluated using the fluorescence probe 2,6-ANS. Based on the emission mechanism and the aspect of inclusion in a hydrophobic cavity, we have suggested that the microenvironmental polarity and viscosity for the excited state of ANS plays an important role for the Φ values of inclusion complexes.

  4. Preventive and therapeutic effects of NF-kappaB inhibitor curcumin in rats colitis induced by trinitrobenzene sulfonic acid

    Institute of Scientific and Technical Information of China (English)

    Yan-Ting Jian; Guo-Feng Mai; Ji-De Wang; Ya-Li Zhang; Rong-Cheng Luo; Yong-Xin Fang

    2005-01-01

    AIM: To ascertain the molecule mechanism of nuclear factor-κB (NF-κB) inhibitor curcumin preventive and therapeutic effects in rats' colitis induced by trinitrobenzene sulfonic acid (TNBS).METHODS: Sixty rats with TNBS-induced colitis weretreated with 2.0% curcumin in the diet. Thirty positive control rats were treated with 0.5% sulfasalazine (SASP).Thirty negative control rats and thirty model rats were treated with general diet. Changes of body weight together with histological scores were evaluated. Survival rates were also evaluated. Cell nuclear NF-κB activity in colonic mucosa was evaluated by using electrophoretic mobility shift assay. Cytoplasmic IκB protein in colonic mucosa was detected by using Western Blot analysis.Cytokine messenger expression in colonic tissue was assessed by using semiquantitative reverse-transcription polymerase chain reaction.RESULTS: Treatment with curcumin could prevent and treat both wasting and histopathologic signs of rats with TNBS-induced intestinal inflammation. In accordance with these findings, NF-κB activation in colonic mucosa was suppressed in the curcumin-treated groups. Degradations of cytoplasmic IκB protein in colonic mucosa were blocked by curcumin treatment. Proinfiammatory cytokine messenger RNA expression in colonic mucosa was also suppressed.CONCLUSION: This study shows that NF-κB inhibitor curcumin could prevent and improve experimental colitis in murine model with inflammatory bowel disease (IBD).The findings suggest that NF-κB inhibitor curcumin could be a potential target for the patients with IBD.

  5. Prevention of tri-nitrobenzene of sulfonic acid-induced colitis in chicken by using extract of Aloe vera

    Directory of Open Access Journals (Sweden)

    Motamed Elsayed Mahmoud

    Full Text Available Aim: Aloe vera, species of succulent plant in the genus Aloe, has multiple clinical activities and used routinely to accelerate wound healing. The present study was designed to investigate the anti-inflammatory effect of Aloe vera extracts (AVE in vitro and in vivo. Materials and Methods: The effect of crude AVE on inducible nitric oxide production by LPS/IFNg-stimulated cultured macrophages was evaluated. The therapeutic effect of administering crude Aloe vera extracts (100 mg/kg b.w. on the development of tri-nitrobenzene of sulfonic acid (TNBS-induced colitis (40 mg/kg b. w. in chicken was also investigated. Chicken is a valuable model for this purpose because it showed preference to bitter taste of Aloe vera. Diverse clinical pictures of the colitis including weight loss, diarrhea and histopathological changes were evaluated. Results: Nitrite production by LPS/IFNg-stimulated macrophages was maximally reduced by adding of AVE (100 μg/ml. This result suggests a direct inhibitory effect of AVE on the inflammatory cells. Chicks treated orally with AVE showed improvement of the histological signs with no inflammatory cell infiltrates and reduction of myeloperoxidase (MPO activities when compared with colitis control group. AVE pretreatment ameliorated significantly the clinical and histopathological severity of the TNBS-induced colitis; decreased body weight loss and diarrhea and increased survival. Conclusion: It was concluded that oral administration of AVE represents a valuable therapeutic approach for the treatment of colitis in chicken. [Vet. World 2012; 5(8.000: 469-476

  6. Dynamics of camphor sulfonic acid in polyaniline (PANI-CSA): a quasielastic neutron scattering study

    Science.gov (United States)

    Bée, M.; Djurado, D.; Combet, J.; Telling, M.; Rannou, P.; Pron, A.; Travers, J. P.

    2001-07-01

    PolyAniline (PANI) doped by camphor sulphonic acid (CSA) exhibits an electronic conductivity of several hundreds of S/cm. All the authors agree to invoke in various extents the role of disorder in the evolution of the transport properties as a function of temperature. The IRIS spectrometer at the Rutherford-Appleton Laboratory was used to remove uncertainties of previous IN6-IN16 experiments at Institut Laue-Langevin. The rigidity of the PANI chains was confirmed, in both a conducting and a partially doped sample. All the observable quasielastic scattering occurs from the CSA dynamics. However, this contribution is too weak in the case of the partially doped specimen to conclude about the coupling of the counter-ion disorder with the electronic transport properties.

  7. 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.

  8. Hyaluronic acid as a rescue therapy for trinitrobenzene sulfonic acid-induced colitis through Cox-2 and PGE2 in a Toll-like receptor 4-dependent way

    Institute of Scientific and Technical Information of China (English)

    Huan CHEN; Mahesh MAHASETH; Yah ZHANG

    2011-01-01

    We hypothesized whether systemic administration of high-molecular-weight hyaluronic acid (HMW HA) could rescue trinitrobenzene sulfonic acid (TNBS)-induced colitis through Toll-like receptor 4 (TLR4) signal.C3H/HeN mice and C3H/HeJ mice were used.Mice were divided into four groups:control,50% ethanol treatment group,TNBS treatment group,and TNBS plus HA treatment group.The weight changes,clinical scores,macroscopic scores,and histological scores were recorded.Cyclooxygenase 2 (Cox-2) and prostaglandin E2 (PGE2) expressions were measured both in colons and peritoneal macrophages from these mice.HA was a rescue therapy for the colitis induced by TNBS only in C3H/HeN mice.The clinical score,macroscopic score,and histological score were much lower in C3H/HeN mice receiving TNBS plus HA treatment.Cox-2 and PGE2 expressions only increased in C3H/HeN mice.These Cox-2 expressing cells were macrophages.HA can also promote the production of Cox-2 and PGE2 in peritoneal macrophages from C3H/HeN mice.Our data demonstrated that HMW HA can rescue TNBS-induced colitis through inducing Cox-2 and PGE2 expressions in a TLR4-dependent way.Macrophages may be the effector cells of HMW HA.

  9. Construction of composite electrodes comprising manganese dioxide nanoparticles distributed in polyaniline-poly(4-styrene sulfonic acid-co-maleic acid) for electrochemical supercapacitor

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Feng-Jiin; Hsu, Tsui-Fen [Department of Chemical Engineering, National United University, 1, Lien Da, Kung-Ching Li, Miao-Li 36003 (China); Yang, Chien-Hsin [Department of Chemical and Materials Engineering, National University of Kaohsiung, Kaohsiung 811 (China)

    2009-06-15

    This work demonstrated a novel and simple route for preparing a composite comprising of manganese oxide (MnO{sub 2}) nanoparticles and polyaniline (PANI) doped poly(4-styrene sulfonic acid-co-maleic acid) (PSSMA) by ''electrochemical doping-deposition''. The PANI-PSSMA-MnO{sub 2} composite was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). SEM images revealed a uniform dispersion of MnO{sub 2} nanoparticles in the porous structure of PANI-PSSMA structure. XRD measurements showed the distortion of the crystal structure of {beta}-MnO{sub 2} after deposition of MnO{sub 2} in PANI-PSSMA structure. Thus, the XRD pattern of PANI was predominating. Cyclic voltammetry and chronopotentiometry were employed in 0.5 M Na{sub 2}SO{sub 4} to evaluate the capacitor properties. The results showed a significant improvement in the specific capacitance of the composite electrode. The specific capacitance of PANI-PSSMA-MnO{sub 2} (50.4 F g{sup -1}) had improvement values of 172% compared to that of PANI (18.5 F g{sup -1}). When only the MnO{sub 2} mass was considered, the composite had a specific capacitance of 556 F g{sup -1}. (author)

  10. Neomycin-loaded poly(styrene sulfonic acid-co-maleic acid) (PSSA-MA)/polyvinyl alcohol (PVA) ion exchange nanofibers for wound dressing materials.

    Science.gov (United States)

    Nitanan, Todsapon; Akkaramongkolporn, Prasert; Rojanarata, Theerasak; Ngawhirunpat, Tanasait; Opanasopit, Praneet

    2013-05-01

    In this study, poly(styrene sulfonic acid-co-maleic acid) (PSSA-MA) blended with polyvinyl alcohol (PVA) was electrospun and then subjected to thermal crosslinking to produce PSSA-MA/PVA ion exchange nanofiber mats. The cationic drug neomycin (0.001, 0.01, and 0.1%, w/v) was loaded onto the cationic exchange fibers. The amount of neomycin loaded and released and the cytotoxicity of the fiber mats were analyzed. In vivo wound healing tests were also performed in Wistar rats. The results indicated that the diameters of the fibers were on the nanoscale (250 ± 21 nm). The ion exchange capacity (IEC) value and the percentage of water uptake were 2.19 ± 0.1 mequiv./g-dry fibers and 268 ± 15%, respectively. The loading capacity was increased upon increasing the neomycin concentration. An initial concentration of 0.1% (w/v) neomycin (F3) showed the highest loading capacity (65.7 mg/g-dry fibers). The neomycin-loaded nanofiber mats demonstrated satisfactory antibacterial activity against both Gram-positive and Gram-negative bacteria, and an in vivo wound healing test revealed that these mats performed better than gauze and blank nanofiber mats in decreasing acute wound size during the first week after tissue damage. In conclusion, the antibacterial neomycin-loaded PSSA-MA/PVA cationic exchange nanofiber mats have the potential for use as wound dressing materials.

  11. Isolation and Characterization of the 2,2'-Azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) Radical Cation-Scavenging Reaction Products of Arbutin.

    Science.gov (United States)

    Tai, Akihiro; Ohno, Asako; Ito, Hideyuki

    2016-09-28

    Arbutin, a glucoside of hydroquinone, has shown strong 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation-scavenging activity, especially in reaction stoichiometry. This study investigated the reaction mechanism of arbutin against ABTS radical cation that caused high stoichiometry of arbutin in an ABTS radical cation-scavenging assay. HPLC analysis of the reaction mixture of arbutin and ABTS radical cation indicated the existence of two reaction products. The two reaction products were purified and identified to be a covalent adduct of arbutin with an ABTS degradation fragment and 3-ethyl-6-sulfonate benzothiazolone. A time-course study of the radical-scavenging reactions of arbutin and the two reaction products suggested that one molecule of arbutin scavenges three ABTS radical cation molecules to generate an arbutin-ABTS fragment adduct as a final reaction product. The results suggest that one molecule of arbutin reduced two ABTS radical cation molecules to ABTS and then cleaved the third ABTS radical cation molecule to generate two products, an arbutin-ABTS fragment adduct and 3-ethyl-6-sulfonate benzothiazolone.

  12. Matrix isolation infrared spectra of O-H· · · π Hydrogen bonded complexes of Acetic acid and Trifluoroacetic acid with Benzene

    Indian Academy of Sciences (India)

    PUJARINI BANERJEE; INDRANI BHATTACHARYA; TAPAS CHAKRABORTY

    2016-10-01

    Mid infrared spectra of two O–H· · · π hydrogen-bonded binary complexes of acetic acid (AA) and trifluoroacetic acid (F₃AA) with benzene (Bz) have been measured by isolating the complexes in an argon matrix at ∼8 K. In a matrix isolation condition, the O–H stretching fundamentals (νO−H) of the carboxylic acid groups of the two molecules are observed to have almost the same value. However, the spectral red-shifts of νO−H bands of the two acids on complexation with Bz are largely different, 90 and 150 cm⁻¹ for AA and F₃AA, respectively. Thus, the O–H bond weakening of the two acids upon binding with Bz in a non-interacting environment follows the sequence of their ionic dissociation tendencies (pKa) in aqueous media. Furthermore, ΔνO−H of the latter complex is the largest among the known π-hydrogen bonded binary complexes of prototypical O–H donors reported so far with respect to Bz as acceptor. It is also observed that the spectral shifts (ΔνO−H) of phenol-Bz and carboxylic acid-Bz complexes show similar dependence on the acidity factor (pKa). Electronic structure theory has been used to suggest suitable geometries of the complexes that are consistent with the measured IR spectral changes. Calculation at MP2/6-311++G (d, p) level predicts a T-shaped geometry for both AA-Bz and F₃AA-Bz complexes, and the corresponding binding energies are 3.0 and 4.5 kcal/mol, respectively. Natural Bond Orbital (NBO) analysis has been performed to correlate the observed spectral behavior of the complexes with the electronic structure parameters.

  13. 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)

  14. One-pot synthesis of pyrido[2,3-d]pyrimidine derivatives using sulfonic acid functionalized SBA-15 and the study on their antimicrobial activities

    Directory of Open Access Journals (Sweden)

    Ghodsi Mohammadi Ziarani

    2015-11-01

    Full Text Available A simple and clean one-pot method for the preparation of 7-amino-2,4-dioxo-5-aryl-1,2,3,4-tetrahydropyrido[2,3-d]pyrimidine-6-carbonitrile derivatives using 6-amino uracil, various aromatic aldehydes and malononitrile in the presence of sulfonic acid functionalized SBA-15 (SBA-Pr-SO3H is described. Some of synthesized pyrido[2,3-d]pyrimidines showed antimicrobial activities against some fungi and gram positive and negative bacteria.

  15. Application of Partial Least Square (PLS) Analysis on Fluorescence Data of 8-Anilinonaphthalene-1-Sulfonic Acid, a Polarity Dye, for Monitoring Water Adulteration in Ethanol Fuel.

    Science.gov (United States)

    Kumar, Keshav; Mishra, Ashok Kumar

    2015-07-01

    Fluorescence characteristic of 8-anilinonaphthalene-1-sulfonic acid (ANS) in ethanol-water mixture in combination with partial least square (PLS) analysis was used to propose a simple and sensitive analytical procedure for monitoring the adulteration of ethanol by water. The proposed analytical procedure was found to be capable of detecting even small adulteration level of ethanol by water. The robustness of the procedure is evident from the statistical parameters such as square of correlation coefficient (R(2)), root mean square of calibration (RMSEC) and root mean square of prediction (RMSEP) that were found to be well with in the acceptable limits.

  16. 不同磺酸掺杂聚苯胺的制备及在超级电容器中的应用%Preparation and Application of Polyaniline Doped with Different Sulfonic Acids for Supercapacitor

    Institute of Scientific and Technical Information of China (English)

    林有铖; 钟新仙; 黄寒星; 王红强; 冯崎鹏; 李庆余

    2016-01-01

    以MnO2为氧化剂,采用乳液聚合法,用三种不同的磺酸型表面活性剂制备掺杂聚苯胺(PANI)。通过扫描电子显微镜(SEM)、傅里叶变换红外(FTIR)光谱以及X射线衍射(XRD)等手段对其结构及形貌进行表征;用所得的掺杂聚苯胺制作电极,组装成对称扣式超级电容器,用循环伏安法(CV)、电化学阻抗(EIS)和恒电流充放电技术进行电化学性能研究。结果表明,磺酸表面活性剂的引入有利于PANI纳米纤维的形成和分散,掺杂Nafion的PANI纤维直径在30-40 nm之间,纤维交织成多孔的疏松结构;当放电电流为0.1 A∙g-1时,以PANI-Nafion、PANI-SDS(十二烷基磺酸钠)、PANI-SDBS(十二烷基苯磺酸钠)为电极材料的超级电容器比容量分别为385.3、359.7、401.6 F∙g-1,均高于未掺杂PANI的比容量(235.8 F∙g-1);其中,PANI-Nafion的循环稳定性最好,1000次循环后其比容量保持率高达70.7%。%Polyaniline (PANI) nanomaterials doped with three different sulfonic acid surfactants (perfluorinated sulfonic acid ion exchange resin (Nafion), sodium dodecyl sulfate (SDS), and sodium dodecyl benzene sulfonate (SDBS)) were prepared using an emulsion polymerization method with manganese dioxide (MnO2) as the oxidant. The structure and morphology of the products were studied by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD). Symmetric redox supercapacitor was assembled with doped PANI as the active electrode material. The electrochemical performances of the materials were evaluated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge-discharge tests. These results suggest that the introduction of surfactant is beneficial for the formation of a fiber structure and increases the dispersion of PANI. A PANI-Nafion network with distributed porosity and average diameters of 30-40 nm is obtained. The

  17. Ion-exclusion chromatographic behavior of aliphatic carboxylic acids and benzenecarboxylic acids on a sulfonated styrene--divinylbenzene co-polymer resin column with sulfuric acid containing various alcohols as eluent.

    Science.gov (United States)

    Ohta, Kazutoku; Towata, Atsuya; Ohashi, Masayoshi

    2003-05-16

    The addition of C1-C7 alcohols (methanol, ethanol, propanol, butanol, heptanol, hexanol and heptanol) to dilute sulfuric acid as eluent in ion-exclusion chromatography using a highly sulfonated styrene-divinylbenzene co-polymer resin (TSKgel SCX) in the H+ form as the stationary phase was carried out for the simultaneous separations of both (a) C1-C7 aliphatic carboxylic acids (formic, acetic, propionic, isobutyric, butyric, isovaleric, valeric, 2-methylvaleric, isocaproic, caproic, 2,2-dimethyl-n-valeric, 2-methylhexanoic, 5-methylhexanoic and heptanoic acids) and (b) benzenecarboxylic acids (pyromellitic, hemimellitic, trimellitic, o-phthalic, m-phthalic, p-phthalic, benzoic and salicylic acids and phenol). Heptanol was the most effective modifier in ion-exclusion chromatography for the improvement of peak shapes and a reduction in retention volumes for higher aliphatic carboxylic acids and benzenecarboxylic acids. Excellent simultaneous separation and relatively highly sensitive conductimetric detection for these C1-C7 aliphatic carboxylic acids were achieved on the TSKgel SCX column (150 x 6 mm I.D.) in 30 min using 0.5 mM sulfuric acid containing 0.025% heptanol as eluent. Excellent simultaneous separation and highly sensitive UV detection at 200 nm for these benzenecarboxylic acids were also achieved on the TSKgel SCX column in 30 min using 5 mM sulfuric acid containing 0.075% heptanol as eluent.

  18. Nafion-assisted cross-linking of sulfonated poly(arylene ether ketone) bearing carboxylic acid groups and their composite membranes for fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Haidan; Zhao, Chengji; Na, Hui [Alan G. MacDiarmid Institute, College of Chemistry, Jilin University, Qianjin street 2699, Changchun 130012, Jilin (China)

    2010-06-01

    In this study, a new type of cross-linked composite membrane is prepared and considered for its potential applications in direct methanol fuel cell. Nafion and sulfonated poly(arylene ether ketone) bearing carboxylic acid groups (SPAEK-C) are blended and subsequently cross-linked by a Friedel-Craft reaction using the carboxylic acid groups in the SPAEK-C to achieve lower methanol permeability. The perfluoroalkyl sulfonic acid groups of Nafion act as a benign solid catalyst, which assist the cross-linking of SPAEK-C. The physical and chemical characterizations of the cross-linked composite membranes are performed by varying the contents of SPAEK-C. The c-Nafion-15% membrane exhibits appropriate water uptake (10.49-25.22%), low methanol permeability (2.57 x 10{sup -7} cm{sup 2} s{sup -1}), and high proton conductivity (0.179 S cm{sup -1} at 80 C). DSC and FTIR analyze suggest the cross-linking reaction. These results show that the self-cross-linking of SPAEK-C in the Nafion membrane can effectively reduce methanol permeability while maintaining high proton conductivity. (author)

  19. Synthesis and Solution Properties of a Sulfonated Allyl Biphenyl Ether-Acrylamide-Acrylic Acid Terpolymer%新型磺化共聚物的合成及其溶液性能

    Institute of Scientific and Technical Information of China (English)

    赵梦奇; 陈德军; 吐尼沙古丽·阿吾提; 司马义·努尔拉

    2012-01-01

    A novel allyl biphenyl ether(ABE)-acrylamide(AM)-acrylic acid(AA) terpolymer was synthesized by emulsion polymerization with ABE as the hydrophobic monomer, lauryl sodium sulfate as the surfactant and azodiisobutyronitrile as the initiator. Water-soluble sulfonated terpolymers with different sulfonated degree were synthesized with concentrated sulfuric acid and oleum as the sulfonating agents. The terpolymer and sulfonated terpolymers were characterized by means of FTIR, 'H NMR and TG. The results show that the sulfonated terpolymers contain the units of ABE, AM and sulfonic groups. The influence of the sulfonic groups on the thermal stability of the sulfonated terpolymers is little. The solubility of both the terpolymer and the sulfonated terpolymers, and the properties of their solutions were studied. The results indicate that the sulfonated terpolymer with the sulphonated degree of 0.56 possesses a good tackability. The sulfonated terpolymer has obvious critical association feature and exhibits better temperature-tolerance and salt-resistance due to the introduction of ABE.%以烯丙基-联苯基醚(ABE)为疏水单体、十二烷基硫酸钠为表面活性剂、偶氮二异丁腈为引发剂,采用乳液自由基聚合法合成了ABE-丙烯酰胺(AM)-丙烯酸(AA)三元共聚物,并以浓硫酸和发烟硫酸为磺化剂对ABE-AM-AA三元共聚物进行磺化改性得到了新型磺化共聚物.采用FTIR和1H NMR方法对磺化共聚物进行了结构表征,并采用TG方法分析了它的热稳定性.表征结果显示,磺化共聚物中含有ABE、AM和磺酸基结构单元;磺酸基的引入对磺化共聚物的热稳定性影响较小.考察了磺化共聚物的溶解性及其溶液性能.实验结果表明,当磺化度为0.56时,磺化共聚物的增黏效果较好;ABE单体的引入使磺化共聚物的溶液具有明显的临界缔合特征和良好的耐温抗盐性能.

  20. Preparation and properties of composite membrane of bisphenol A-based sulfonated poly(arylene ether sulfone) and phosphotungstic acid for proton exchange membranes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ni; LIU Hui-ling; LI Jun-jing; XIA Zhi

    2010-01-01

    A series of bi A-SPAES (Ds=0.4)/phosphotungstic acid (PWA/bi A-SPAES) composite membranes with various contents of PWA were prepared and characterized by FT-IR.Scanning electron microscopy (SEM) images indicated the PWA were well dispersed within polymer matrix.These composite membranes were evaluated for proton exchange membranes (PEM) in direct methanol fuel cell (DMFC).These membranes showed good thermal stability.It was found that the water uptake of these membranes increased with the increase of the PWA content in the hybrid membranes.Meanwhile,the introduction of inorganic particles increased both the proton conductivity and the methanol permeability.The proton conductivities of composite membranes were increased from 0.017 S/cm to 0.045 S/cm at 20 ℃ and from 0.054 S/cm to 0.093 S/cm at 100 ℃ with the increase of PWA content from 0 to 50 %.Especially,all the methanol diffusion coefficients (4.20×10-8-1.05×10-7 cm2/s) of bi A-SPAES/PWA hybrid membranes are much lower than that of Nafion 117 membrane (2.1×10-6 cm2/s).Bi A-SPAES/PWA hybrid membranes were therefore proposed as candidates of material for PEM in DMFC.

  1. 氨基磺酸催化合成脂肪酸丁酯的研究%Synthesis of fatty acid butyl ester catalyzed by amino sulfonic acid

    Institute of Scientific and Technical Information of China (English)

    程正载; 龚凯; 张卫星; 高松; 雷锐; 颜晓潮; 从野

    2014-01-01

    The fatty acid butyl ester was respectively synthesized by the esterification of oleic acid with bu-tanol and the transesterification of rapeseed oil with butanol catalyzed by amino sulfonic acid. The fatty acid butyl ester product was analyzed by GC and its structure was characterized by FT-IR. The effects of molar ratio of butanol to oil ( oleic acid or rapeseed oil) , catalyst dosage, reaction temperature and reac-tion time on the conversion rates of oleic acid and rapeseed oil were investigated. The results showed that the optimal esterification conditions were obtained as follows: molar ratio of butanol to oleic acid 3∶1 , catalyst dosage 0. 8% (based on the mass of oleic acid), reaction temperature 110℃and reaction time 1. 5 h. Under these conditions, the conversion rate of oleic acid and the yield of fatty acid butyl ester reached 88. 6% and 83. 5%, respectively. The optimal transesterification conditions were obtained as follows:molar ratio of butanol to rapeseed oil 10∶1, catalyst dosage 1. 0% (based on the mass of rapeseed oil), reaction temperature 115℃ and reaction time 2. 0 h. Under the optimal conditions, the conversion rate of rapeseed oil and the yield of fatty acid butyl ester achieved 85. 6% and 80. 1%, respectively.%以氨基磺酸为催化剂,油酸及菜籽油与正丁醇分别进行酯化反应与酯交换反应制备脂肪酸丁酯。并利用气相色谱及红外光谱对产物进行分析及结构表征。考察了醇(正丁醇)油(油酸及菜籽油)摩尔比、催化剂用量、反应温度和反应时间对油酸及菜籽油转化率的影响。结果表明,油酸酯化反应的最佳工艺条件为:醇油摩尔比3∶1,催化剂用量为油酸质量的0.8%,反应温度110℃,反应时间1.5 h,此时油酸转化率达到88.6%,产品收率为83.5%;菜籽油酯交换反应的最佳工艺条件为:醇油摩尔比10∶1,催化剂用量为菜籽油质量的1.0%,反应温度115℃,反应时间2.0 h,

  2. Biocompatibility of polypropylene non-woven fabric membrane via UV-induced graft polymerization of 2-acrylamido-2-methylpropane sulfonic acid

    Energy Technology Data Exchange (ETDEWEB)

    Song Lingjie [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Zhao Jie; Yang Huawei; Jin Jing; Li Xiaomeng [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Stagnaro, Paola [Istituto per Io Studio delle Macromolecole, Consiglio Nazionale delle Ricerche, Via de Marini 6, 16149 Genova (Italy); Yin Jinghua, E-mail: yinjh@ciac.jl.cn [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2011-10-15

    This work described the graft polymerization of a sulfonic acid terminated monomer, 2-acrylamido-2-methylpropane sulfonic acid (AMPS), onto the surface of polypropylene non-woven (NWF PP) membrane by O{sub 2} plasma pretreatment and UV-induced photografting method. The chemical structure and composition of the modified surfaces were analyzed by FTIR-ATR and XPS, respectively. The wettability was investigated by water contact angle and equilibrium water adsorption. And the biocompatibility of the modified NWF PP membranes was evaluated by protein adsorption and platelet adhesion. It was found that the graft density increased with prolonging UV irradiation time and increasing AMPS concentration; the water contact angles of the membranes decreased from 124{sup o} to 26{sup o} with the increasing grafting density of poly(AMPS) from 0 to 884.2 {mu}g cm{sup -2}, while the equilibrium water adsorption raised from 5 wt% to 75 wt%; the protein absorption was effectively suppressed with the introduction of poly(AMPS) even at the low grafting density (132.4 {mu}g cm{sup -2}); the number of platelets adhering to the modified membrane was dramatically reduced when compared with that on its virgin surface. These results indicated that surface modification of NWF PP membrane with AMPS was a facile approach to construct biocompatible surface.

  3. Mercapturic acids in urine as an index for indoor air exposition to benzene and toluene; Merkaptursaeuren im Urin als Index fuer Innenraum-Expositionen von Benzol und Toluol

    Energy Technology Data Exchange (ETDEWEB)

    Rolle-Kampczyk, U.; Rehwagen, M.; Herbarth, O. [UFZ-Umweltforschungzentrum Leipzig-Halle GmbH, Leipzig (Germany). Sektion Expositionsforschung und Epidemiologie

    1998-10-01

    Benzene toxicity and the relatively high toluene burden of indoor air necessitate the examination of urine for specific metabolites as a verification for the internal exposure and dose. Selected were S-phenyl- and S-benzyl-mercapturic acid (SPMA and SBMA), and their concentrations determined in the urine samples of children from Leipzig. The results were correlated with the benzene and toluene concentrations of indoor air. Whereas a weak correlation was found between benzene and SPMA, no relationship was found between toluene and SBMA. (orig.) [Deutsch] Auf Grund der toxikologischen Bedenklichkeit von Benzol und der relativ hohen Toluolbelastung von Innenraeumen sollen spezifische Metaboliten fuer diese Stoffe im Urin als Nachweis fuer die tatsaechlich aufgenommenen Schadstoffmengen untersucht werden. Es wurden S-Phenyl- und S-Benzyl-Merkaptursaeure (SPMA und SBMA) ausgewaehlt und deren Konzentrationen im Urin Leipziger Kinder bestimmt. Die Ergebnisse wurden mit den Raumluftkonzentrationen von Benzol und Toluol korreliert. Waehrend sich zwischen Benzol und SPMA ein schwacher korrelativer Zusammenhang herausstellte, ergab sich zwischen Toluol und SBMA keine Korrelation. (orig.)

  4. Properties of polypyrrole doped with alkylbenzene sulfonates

    Science.gov (United States)

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

    2001-07-01

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

  5. Benzene Uptake and Glutathione S-transferase T1 Status as Determinants of S-Phenylmercapturic Acid in Cigarette Smokers in the Multiethnic Cohort.

    Directory of Open Access Journals (Sweden)

    Christopher A Haiman

    Full Text Available Research from the Multiethnic Cohort (MEC demonstrated that, for the same quantity of cigarette smoking, African Americans and Native Hawaiians have a higher lung cancer risk than Whites, while Latinos and Japanese Americans are less susceptible. We collected urine samples from 2,239 cigarette smokers from five different ethnic groups in the MEC and analyzed each sample for S-phenylmercapturic acid (SPMA, a specific biomarker of benzene uptake. African Americans had significantly higher (geometric mean [SE] 3.69 [0.2], p<0.005 SPMA/ml urine than Whites (2.67 [0.13] while Japanese Americans had significantly lower levels than Whites (1.65 [0.07], p<0.005. SPMA levels in Native Hawaiians and Latinos were not significantly different from those of Whites. We also conducted a genome-wide association study in search of genetic risk factors related to benzene exposure. The glutathione S-transferase T1 (GSTT1 deletion explained between 14.2-31.6% (p = 5.4x10-157 and the GSTM1 deletion explained between 0.2%-2.4% of the variance (p = 1.1x10-9 of SPMA levels in these populations. Ethnic differences in levels of SPMA remained strong even after controlling for the effects of these two deletions. These results demonstrate the powerful effect of GSTT1 status on SPMA levels in urine and show that uptake of benzene in African American, White, and Japanese American cigarette smokers is consistent with their lung cancer risk in the MEC. While benzene is not generally considered a cause of lung cancer, its metabolite SPMA could be a biomarker for other volatile lung carcinogens in cigarette smoke.

  6. Proton conductivity and fuel cell property of composite electrolyte consisting of Cs-substituted heteropoly acids and sulfonated poly(ether-ether ketone)

    Energy Technology Data Exchange (ETDEWEB)

    Oh, S.Y.; Yoshida, T.; Kawamura, G.; Sakai, M.; Matsuda, A. [Department of Materials Science, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 441-8580 (Japan); Muto, H. [Department of Materials Science and Engineering, Kurume National College of Technology, 1-1-1 Komorino, Kurume, Fukuoka 830-8555 (Japan)

    2010-09-15

    Inorganic-organic composite electrolytes were fabricated from partially Cs{sup +}-substituted heteropoly acids (Cs-HPAs) and sulfonated poly(ether-ether ketone) (SPEEK) for application in fuel cells. Heteropoly acids, such as phosphotungstic acid (H{sub 3}PW{sub 12}O{sub 40}:WPA), and silicotungstic acid (H{sub 4}SiW{sub 12}O{sub 40}:WSiA), were mechanochemically treated with cesium hydrogen sulfate (CsHSO{sub 4}) to obtain the form of Cs-HPAs. SPEEK was prepared from PEEK by sulfonation using concentrated sulfuric acid. Water durability and surface structure of HPAs were modified by introducing Cs{sup +} into HPAs. Flexible and hot water stable composite electrolytes were obtained, and their electrochemical properties were markedly improved with the addition of Cs-HPAs into the SPEEK matrix. Maximum power densities of 245 and 247 mW cm{sup -2} were obtained for 50WPA.50CsHSO{sub 4} and 50WSiA.50CsHSO{sub 4} in SPEEK (1/5 by weight) composite electrolytes, respectively, from single cell tests at 80 C and 80 RH%. These results suggest that a three-dimensional proton-conductive path was formed among homogeneously distributed Cs-HPAs particles in the SPEEK matrix. The Cs-HPAs incorporated into the SPEEK matrix increased the number of protonate sites in the electrolyte. These observations imply that the mechanochemically synthesized Cs-HPAs, which consist of hydrogen bondings between Cs-HPAs and -HSO{sub 4}{sup -}, dissociated from CsHSO{sub 4}, are promising materials as inorganic fillers in inorganic-organic composite. (author)

  7. Proton conductivity and fuel cell property of composite electrolyte consisting of Cs-substituted heteropoly acids and sulfonated poly(ether-ether ketone)

    Science.gov (United States)

    Oh, S. Y.; Yoshida, T.; Kawamura, G.; Muto, H.; Sakai, M.; Matsuda, A.

    Inorganic-organic composite electrolytes were fabricated from partially Cs +-substituted heteropoly acids (Cs-HPAs) and sulfonated poly(ether-ether ketone) (SPEEK) for application in fuel cells. Heteropoly acids, such as phosphotungstic acid (H 3PW 12O 40:WPA), and silicotungstic acid (H 4SiW 12O 40:WSiA), were mechanochemically treated with cesium hydrogen sulfate (CsHSO 4) to obtain the form of Cs-HPAs. SPEEK was prepared from PEEK by sulfonation using concentrated sulfuric acid. Water durability and surface structure of HPAs were modified by introducing Cs + into HPAs. Flexible and hot water stable composite electrolytes were obtained, and their electrochemical properties were markedly improved with the addition of Cs-HPAs into the SPEEK matrix. Maximum power densities of 245 and 247 mW cm -2 were obtained for 50WPA·50CsHSO 4 and 50WSiA·50CsHSO 4 in SPEEK (1/5 by weight) composite electrolytes, respectively, from single cell tests at 80 °C and 80 RH%. These results suggest that a three-dimensional proton-conductive path was formed among homogeneously distributed Cs-HPAs particles in the SPEEK matrix. The Cs-HPAs incorporated into the SPEEK matrix increased the number of protonate sites in the electrolyte. These observations imply that the mechanochemically synthesized Cs-HPAs, which consist of hydrogen bondings between Cs-HPAs and -HSO 4 -, dissociated from CsHSO 4, are promising materials as inorganic fillers in inorganic-organic composite.

  8. Methodological issues in the biological monitoring of urinary benzene and S-phenylmercapturic acid at low exposure levels.

    Science.gov (United States)

    Fustinoni, Silvia; Campo, Laura; Mercadante, Rosa; Manini, Paola

    2010-10-01

    Biological monitoring of low level exposure to pollutants is a very challenging analytical activity, and the quality of results is difficult to assess, especially when a certified reference material is unavailable. The aim of this work was to evaluate the reliability of the assays used to measure urinary benzene (Benz-U) and S-phenylmercapturic acid (SPMA), by applying an internal quality control protocol. Urine spot samples from 705 subjects who were either members of the general urban population, gasoline station attendants, or refinery plant workers were assayed for Benz-U and SPMA, using GC/MS and LC/MS/MS, with quantification limits of 15 ng/L and 0.10 μg/L. The median Benz-U concentration was 263 ng/L (60-2789 ng/L, 5th-95th percentile), and the median SPMA concentration was 0.19 μg/L (<0.1-2.5 μg/L, 5th-95th percentile). Linearity of both assays was good, but a less-than-proportional response was found for SPMA concentrations below 1 μg/L. Between-run precision and accuracy for Benz-U concentration determination were assessed using quality controls at 120 ng/L and 1000 ng/L and were 10.3% and 4.8%, and 104.8% and 98.9%, respectively; while the precision and accuracy for SPMA concentration determination at 0.3 μg/L, 2.5 μg/L, and 20 μg/L were 40.3%, 6.2%, and 6.2%, and 48.3%, 96.3%, and 98.8%, respectively. Precision, estimated using duplicates of unknown samples, was 13.4% for Benz-U and 26.5% for SPMA analyses. Control charts for the means of the slope of the linear calibration curve of Benz-U showed good stability of the means over a five-year period. For SPMA, a two-laboratory comparison revealed acceptable agreement between ln-transformed data pairs, with a slope of the linear regression of 0.863 (confidence interval 0.774-0.952), null intercept, and a Pearson's r value of 0.844. Reliable results were obtained for Benz-U analyses over the entire concentration range, and for high and medium SPMA levels. However, the determination of SPMA

  9. Preparation and characterization of poly(2-acrylamido-2-methylpropane-sulfonic acid)/Chitosan hydrogel using gamma irradiation and its application in wastewater treatment

    Energy Technology Data Exchange (ETDEWEB)

    Gad, Y.H. [National Centre for Radiation Research and Technology, P.O. Box 29, Nasr City, Cairo (Egypt)], E-mail: yasser2uk@yahoo.com

    2008-09-15

    Radiation grafting of chitosan with 2-acrylamido-2-methyl propane sulfonic acid (AMPS) has been successfully performed. The effect of absorbed dose (kGy) and the chitosan:AMPS ratio on graft hydrogelization was studied. The structure of the prepared hydrogel was confirmed using infrared spectroscopy (IR). Thermal properties were simultaneously studied by thermogravimetric analysis (TGA). The effect of the polymerization variables on the swelling % of the prepared hydrogel was investigated. The highest equilibrium degree of swelling (38.6 g/g) and gel % (94.7%) of the prepared chitosan-AMPS hydrogel was at 40% AMPS and absorbed dose of 10 kGy. The removal of methylene blue, acid red dye, Cd (II) and Cr (III) from composed wastewater was also investigated. The effect of pH, the chitosan:AMPS ratio and the concentration of the pollutant on the adsorption process were studied.

  10. Preparation and characterization of poly(2-acrylamido-2-methylpropane-sulfonic acid)/Chitosan hydrogel using gamma irradiation and its application in wastewater treatment

    Science.gov (United States)

    Gad, Y. H.

    2008-09-01

    Radiation grafting of chitosan with 2-acrylamido-2-methyl propane sulfonic acid (AMPS) has been successfully performed. The effect of absorbed dose (kGy) and the chitosan:AMPS ratio on graft hydrogelization was studied. The structure of the prepared hydrogel was confirmed using infrared spectroscopy (IR). Thermal properties were simultaneously studied by thermogravimetric analysis (TGA). The effect of the polymerization variables on the swelling % of the prepared hydrogel was investigated. The highest equilibrium degree of swelling (38.6 g/g) and gel % (94.7%) of the prepared chitosan-AMPS hydrogel was at 40% AMPS and absorbed dose of 10 kGy. The removal of methylene blue, acid red dye, Cd (II) and Cr (III) from composed wastewater was also investigated. The effect of pH, the chitosan:AMPS ratio and the concentration of the pollutant on the adsorption process were studied.

  11. Acid-base blend membranes based on 2-amino-benzimidazole and sulfonated poly(ether ether ketone) for direct methanol fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Yongzhu; Manthiram, Arumugam [Materials Science and Engineering Program, The University of Texas at Austin, Austin, TX 78712 (United States); Guiver, Michael D. [Institute for Chemical Process and Environmental Technology, National Research Council of (Canada)

    2007-05-15

    Direct methanol fuel cells (DMFC) are attractive for portable and automobile power needs, but their commercialization is hampered by high methanol permeability and the high cost of the currently used Nafion membrane. We report here a novel, low-cost blend membrane consisting of polysulfone-2-amide-benzimidazole (a basic polymer) and sulfonated poly(ether ether ketone) (an acidic polymer), which facilitates proton conduction through acid-base interactions while preserving excellent chemical and mechanical stabilities. The blend membrane exhibits performance in DMFC much higher than that of Nafion 115 and similar to that of Nafion 112, but with a remarkably superior long-term performance than Nafion 112 due to significantly reduced methanol crossover, enhancing the commercialization prospects of DMFC. (author)

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

    OpenAIRE

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

    2000-01-01

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

  13. Identification of Novel Perfluoroalkyl Ether Carboxylic Acids (PFECAs) and Sulfonic Acids (PFESAs) in Natural Waters Using Accurate Mass Time-of-Flight Mass Spectrometry (TOFMS).

    Science.gov (United States)

    Strynar, Mark; Dagnino, Sonia; McMahen, Rebecca; Liang, Shuang; Lindstrom, Andrew; Andersen, Erik; McMillan, Larry; Thurman, Michael; Ferrer, Imma; Ball, Carol

    2015-10-06

    Recent scientific scrutiny and concerns over exposure, toxicity, and risk have led to international regulatory efforts resulting in the reduction or elimination of certain perfluorinated compounds from various products and waste streams. Some manufacturers have started producing shorter chain per- and polyfluorinated compounds to try to reduce the potential for bioaccumulation in humans and wildlife. Some of these new compounds contain central ether oxygens or other minor modifications of traditional perfluorinated structures. At present, there has been very limited information published on these "replacement chemistries" in the peer-reviewed literature. In this study we used a time-of-flight mass spectrometry detector (LC-ESI-TOFMS) to identify fluorinated compounds in natural waters collected from locations with historical perfluorinated compound contamination. Our workflow for discovery of chemicals included sequential sampling of surface water for identification of potential sources, nontargeted TOFMS analysis, molecular feature extraction (MFE) of samples, and evaluation of features unique to the sample with source inputs. Specifically, compounds were tentatively identified by (1) accurate mass determination of parent and/or related adducts and fragments from in-source collision-induced dissociation (CID), (2) in-depth evaluation of in-source adducts formed during analysis, and (3) confirmation with authentic standards when available. We observed groups of compounds in homologous series that differed by multiples of CF2 (m/z 49.9968) or CF2O (m/z 65.9917). Compounds in each series were chromatographically separated and had comparable fragments and adducts produced during analysis. We detected 12 novel perfluoroalkyl ether carboxylic and sulfonic acids in surface water in North Carolina, USA using this approach. A key piece of evidence was the discovery of accurate mass in-source n-mer formation (H(+) and Na(+)) differing by m/z 21.9819, corresponding to the

  14. Key factors in developing the trinitrobenzene sulfonic acid-induced post-inflammatory irritable bowel syndrome model in rats

    Institute of Scientific and Technical Information of China (English)

    Hong-Yan Qin; Hai-Tao Xiao; Justin CY Wu; Brian M Berman; Joseph JY Sung; Zhao-Xiang Bian

    2012-01-01

    AIM:To investigate the key factors in developing the trinitrobenzene sulfonic acid (TNBS)-induced postinflammatory irritable bowel syndrome (PI-IBS) model in rats.METHODS:TNBS was administered to rats at the following conditions:(1) with different doses (20,10,5mg/0.8 mL per rat); (2) with same dose in different concentrations (20 mg/rat,25,50 mg/mL); (3) in different ethanol percentage (25%,50%); and (4) at depth either 4 cm or 8 cm from anus.At 5 d and 4 wk after TNBS administration,inflammation severity and inflammation resolution were evaluated.At 4 and 8 wk after TNBS application,visceral hyperalgesia and enterochromaffin (EC) cell hyperplasia were assayed by abdominal withdrawal reflex test,silver staining and capillary electrophoresis.RESULTS:Our results showed that:(1) TNBS induced dose-dependent acute inflammation and inflammation resolution.At 5 d post TNBS,the pathological score and myeloperoxidase (MPO) activity in all TNBS treated rats were significantly elevated compared to that of the control (9.48 ± 1.86,8.18 ± 0.67,5.78 ±0.77 vs 0,and 3.55 ± 1.11,1.80 ± 0.82,0.97 ± 0.08unit/mg vs 0.14 ± 0.01 unit/mg,P < 0.05).At 4 wk post TNBS,the pathological score in high and median dose TNBS-treated rats were still significantly higher than that of the control (1.52 ± 0.38 and 0.80 ± 0.35vs 0,P < 0.05); (2) Intracolonic TNBS administration position affected the persistence of visceral hyperalgesia.At 4 wk post TNBS,abdominal withdrawal reflex (AWR) threshold pressure in all TNBS-treated groups were decreased compared to that of the control (21.52± 1.73 and 27.10 ± 1.94 mmHg vs 34.44 ± 1.89mmHg,P < 0.05).At 8 wk post TNBS,AWR threshold pressure in 8 cm administration group was still significantly decreased (23.33 ± 1.33 mmHg vs 36.79 ± 2.29mmHg,P < 0.05); (3) Ethanol percentage affected the TNBS-induced inflammation severity and visceral hyperalgesia.In TNBS-25% ethanol-treated group,the pathological score and MPO activity were

  15. Crosslinked sulfonated poly(arylene ether ketone) membranes bearing quinoxaline and acid-base complex cross-linkages for fuel cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xinbing; Chen, Pei; An, Zhongwei [Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Materials Science, Shaanxi Normal University, Xi' an 710062 (China); Chen, Kangcheng; Okamoto, Kenichi [Graduate School of Science and Engineering, Yamaguchi University, Tokiwadai 2-16-1, Ube, Yamaguchi 755-8611 (Japan)

    2011-02-15

    A series of crosslinkable sulfonated poly(arylene ether ketone)s (SPAEKs) were synthesized by copolymerization of 4,4'-biphenol with 2,6-difluorobenzil and 5,5'-carbonyl-bis(2-fluorobenzene-sulfonate). A facile crosslinking method was successfully developed, based on the cyclocondensation reaction of benzil moieties in polymer chain with 3,3'-diaminobenzidine to form quinoxaline groups acting as covalent and acid-base ionic crosslinking. The uncrosslinked and crosslinked SPAEK membranes showed high mechanical properties and the isotropic membrane swelling, while the later became insoluble in tested polar aprotic solvents. The crosslinking significantly improved the membrane performance, i.e., the crosslinked membranes had the lower membrane dimensional change, lower methanol permeability and higher oxidative stability than the corresponding precursor membranes, with keeping the reasonably high proton conductivity. The crosslinked membrane (C-B4) with an ion exchange capacity of 2.02 mequiv. g{sup -1} showed a reasonably high proton conductivity of 111 mS cm{sup -1} with a low water uptake of 42 wt% at 80 C. C-B4 exhibited a low methanol permeability of 0.55 x 10{sup -6} cm{sup 2} s{sup -1} for 32 wt% methanol solution at 25 C. The crosslinked SPAEK membranes have potential for PEFC and DMFC applications. (author)

  16. 微波辐射对甲苯磺酸催化合成对羟基苯甲酸乙二醇单酯%Synthesis of mono-4-hydroxybenzoic acid ethylene glycol ester catalyzed by p-toluene sulfonic acid under microwave radiation

    Institute of Scientific and Technical Information of China (English)

    杨晓军; 冯小丽; 张谋真

    2012-01-01

    Mono 4-hydroxybenzoic acid ethylene glycol ester was synthesized by using 4-hydroxybenzoic acid and ethylene glycol as the raw materials and p -methyl benzene sulfonic acid as the catalyst under microwave radiation. The product was characterized by IR and NMR. The influence of microwave radiation power and time, catalyst dosage, and molar ratio of the reactants on the yield was investigated. The results showed that the esterification yield of 92. 1 % was attained under the optimal synthesis condition as follows ; microwave radiation power 500 W, catalyst dosage 0.28 g, molar ratio of the reactants 1:3.5 and microwave radiation time 20 min.%在微波辐射下,研究了以对甲苯磺酸为催化剂,对羟基苯甲酸和乙二醇为原料合成对羟基苯甲酸乙二醇单酯的工艺条件.用红外光谱分析和核磁共振光谱等方法对产物的结构进行表征,考察微波辐射功率、催化剂用量、酸醇物质的量比以及微波辐射时间对酯化率的影响.结果表明,合成对羟基苯甲酸乙二醇单酯的优化条件为:微波辐射功率500W,酸醇物质的量比为1∶3.5,催化剂用量0.28 g,微波辐射时间20 min,此条件下,酯化率达92.1%.

  17. Matrix Isolation Infrared Spectroscopy of an O-H···π Hydrogen-Bonded Complex between Formic Acid and Benzene.

    Science.gov (United States)

    Banerjee, Pujarini; Bhattacharya, Indrani; Chakraborty, Tapas

    2016-05-26

    Mid-infrared spectra of an O-H···π hydrogen-bonded 1:1 complex between formic acid and benzene were measured by isolating the complex in an argon matrix at a temperature of 8 K. The O-H stretching fundamental of formic acid (νO-H) undergoes a red shift of 120 cm(-1), which is the largest among the known π-hydrogen bonded complexes of an O-H donor with respect to benzene as acceptor. Electronic structure theory methods were used extensively to suggest a suitable geometry of the complex that is consistent with a recent study performed at CCSD(T)/CBS level by Zhao et al. (J. Chem. Theory Comput. 2009, 5, 2726-2733), as well as with the measured IR spectral shifts of the present study. It has been determined that density functional theory (DFT) D functionals as well as parametrized DFT functionals like M06-2X, in conjunction with modestly sized basis sets like 6-31G (d, p), are sufficient for correct predictions of the spectral shifts observed in our measurement and also for reproducing the value of the binding energy reported by Zhao et al. We also verified that these low-cost methods are sufficient in predicting the νO-H spectral shifts of an analogous O-H···π hydrogen-bonded complex between phenol and benzene. However, some inconsistencies with respect to shifts of νO-H arise when diffuse functions are included in the basis sets, and the origin of this anomaly is shown to lie in the predicted geometry of the complex. Natural bond orbital (NBO) and atoms-in-molecule (AIM) analyses were performed to correlate the spectral behavior of the complex with its geometric parameters.

  18. Occupational exposure to low levels of benzene: Biomarkers of exposure and nucleic acid oxidation and their modulation by polymorphic xenobiotic metabolizing enzymes.

    Science.gov (United States)

    Manini, Paola; De Palma, Giuseppe; Andreoli, Roberta; Mozzoni, Paola; Poli, Diana; Goldoni, Matteo; Petyx, Marta; Apostoli, Pietro; Mutti, Antonio

    2010-04-01

    This study investigated nucleic acid oxidation associated with exposure to benzene at low levels in 239 workers recruited among traffic policemen, taxi drivers and gasoline pump attendants of the city of Parma (Italy). Biomarkers of exposure, namely urinary t,t-muconic acid (t,t-MA) and S-phenylmercapturic acid (S-PMA), urinary cotinine, and urinary biomarkers of nucleic acid oxidation, namely 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo), 8-oxo-7,8-dihydroguanosine (8-oxoGuo) and 8-oxo-7,8-dihydroguanine (8-oxoGua) were determined by liquid chromatography-tandem mass spectrometry. Relevant polymorphisms of NAD(P)H:quinone oxidoreductase (NQO1), glutathione S-transferases M1-1 (GSTM1), T1-1 (GSTT1), and A1 (GSTA1) were characterized by polymerase chain reaction-based methods in a subgroup of subjects. Biomarkers of nucleic acid oxidation were correlated with each other (r> or =0.32, p or =0.28, p<0.0001). Multiple linear regression models including age, sex and smoking habits as independent variables demonstrated that benzene exposure is associated with oxidation damage to nucleic acid, particularly to RNA (p<0.0001) and is modulated by the NQO1 polymorphism. The study confirmed a significant modulating effect of GSTM1 (p=0.010), GSTT1 (p=0.023) and GSTA1 (p=0.048) polymorphisms on S-PMA excretion, with a significant interaction between GSTM1 and both GSTT1 and GSTA1 (p=0.006 and p=0.037, respectively).

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

    NARCIS (Netherlands)

    Temmink, B.G.; Klapwijk, A.

    2004-01-01

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

  20. Enhanced conductivity of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) film by acid treatment for indium tin oxide-free organic solar cells

    Science.gov (United States)

    Lin, Chun-Chiao; Huang, Chih-Kuo; Hung, Yu-Chieh; Chang, Mei-Ying

    2016-08-01

    An acid treatment is used in the enhancement of the conductivity of the conducting polymer poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) thin film, which is often used as the anode in organic solar cells. There are three types of acid treatment for PEDOT:PSS thin film: hydrochloric, sulfuric, and phosphoric acid treatments. In this study, we examine and compare these three ways with each other for differences in conductivity. Hydrochloric acid results in the highest conductivity enhancement, from 0.3 to 1109 S/cm. We also discuss the optical transmittance, conductivity, surface roughness, surface morphology, and stability, as well as the factors that can influence device efficiency. The devices are fabricated using an acid-treated PEDOT:PSS thin film as the anode. The highest power conversion efficiency was 1.32%, which is a large improvement over that of the unmodified organic solar cell (0.21%). It is comparable to that obtained when using indium tin oxide (ITO) as an electrode, ca. 1.46%.

  1. Carboxylic acid functionalized ortho-linked oxacalix[2]benzene[2]pyrazine: synthesis, structure, hydrogen bond and metal directed self-assembly.

    Science.gov (United States)

    Kong, Ling-Wei; Ma, Ming-Liang; Wu, Liang-Chun; Zhao, Xiao-Li; Guo, Fang; Jiang, Biao; Wen, Ke

    2012-05-14

    Cyclooligomerization of 2,6-dichloropyrazine 4 and benzyl 2,3-dihydroxybenzoate 5 under microwave irradiation resulted in a racemic pair of ester functionalized ortho-linked oxacalix[2]benzene[2]pyrazine 6, which was further transformed to the corresponding racemic carboxylic acid functionalized ortho-linked oxacalix[2]benzene[2]pyrazine 3. Both enantiomers of 3 adopt 1,3-alternate conformations with their two carboxylic acid groups pointing to opposite directions in the solid state. Enantiomers of 3 form a step-like one-dimensional supramolecular polymer via intermolecular hydrogen bond interactions between the carboxylic acids for crystals obtained in methanol. No hydrogen bonds were formed between the carboxylic acids for crystals of 3 obtained in pyridine and aqueous guanidine solutions; instead, intermolecular hydrogen bonds between the carboxylic acid groups of 3 and pyridine, as well as guanidinium ions were formed. Under metal-mediated self-assembly conditions, the pyrazinyl nitrogen atoms in 3 interacted with transition metal ions, such as Ag(I), Cu(II) and Zn(II), and resulted in the formation of four new metal-containing supramolecular complexes. Metallomacrocycles 7, 8 and 9 were formed by reactions of 3 with Ag(I) or Cu(II) ions by bridging two ligands 3 in the equatorial region via M-N coordination bonds. A one-dimensional coordination polymer 10 was generated by reaction between ligand 3 and Zn(II) ions, and a cage-based structure is presented in 10 by bridging of the cyclophane units by Zn(2+) ions via Zn-N and Zn-O bonds.

  2. β–Cyclodextrin–Propyl Sulfonic Acid Catalysed One-Pot Synthesis of 1,2,4,5-Tetrasubstituted Imidazoles as Local Anesthetic Agents

    Directory of Open Access Journals (Sweden)

    Yan Ran

    2015-11-01

    Full Text Available Some functionalized 1,2,4,5-tetrasubstituted imidazole derivatives were synthesized using a one-pot, four component reaction involving 1,2-diketones, aryl aldehydes, ammonium acetate and substituted aromatic amines. The synthesis has been efficiently carried out in a solvent free medium using β-cyclodextrin-propyl sulfonic acid as a catalyst to afford the target compounds in excellent yields. The local anesthetic effect of these derivatives was assessed in comparison to lidocaine as a standard using a rabbit corneal and mouse tail anesthesia model. The three most potent promising compounds were subjected to a rat sciatic nerve block assay where they showed considerable local anesthetic activity, along with minimal toxicity. Among the tested analogues, 4-(1-benzyl-4,5-diphenyl-1H-imidazol-2-yl-N,N-dimethylaniline (5g was identified as most potent analogue with minimal toxicity. It was further characterized by a more favourable therapeutic index than the standard.

  3. A complementary electrochromic device based on polyaniline tethered polyhedral oligomeric silsesquioxane and poly(3,4-ethylenedioxythiophene)/poly(4-styrene sulfonic acid)

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Shanxin [Temasek Laboratories, Nanyang Technological University, 50 Nanyang Drive, Singapore 637553 (Singapore); Ma, Jan; Lu, Xuehong [Temasek Laboratories, Nanyang Technological University, 50 Nanyang Drive, Singapore 637553 (Singapore); School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

    2009-12-15

    A high-contrast complementary electrochromic device based on polyaniline (PANI) tethered polyhedral oligomeric silsesquioxane (POSS) (POSS-PANI) and poly(3,4-ethylenedioxythiophene)/poly(4-styrene sulfonic acid) (PEDOT:PSS) is assembled. The electrochromic properties, cyclic voltammetry behavior and coloration efficiency of the device are studied. Due to the loosely packed structure, POSS-PANI gives rise to a significantly higher electrochromic contrast, coloration efficiency and faster switching speed than PANI. Despite its high contrast, the combination of POSS-PANI with PEDOT:PSS still shows synergy in terms of contrast enhancement, which can be attributed to the additional driving force for the diffusion of dopants into PEDOT:PSS provided by the dedoping of POSS-PANI. (author)

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

    Science.gov (United States)

    Hampel, M; Blasco, J

    2002-01-01

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

  5. Camphor-10-sulfonic acid catalyzed condensation of 2-naphthol with aromatic/aliphatic aldehydes to 14-aryl/alkyl-14H-dibenzo[a,j]xanthenes

    Directory of Open Access Journals (Sweden)

    Kundu Kshama

    2014-01-01

    Full Text Available (±-Camphor-10-sulfonic acid (CSA catalyzed condensation of 2-naphthol with both aliphatic/aromatic aldehydes at 80°C yielded 14-alkyl/aryl-dibenzoxanthenes as the sole product in high yields. However, the same condensation with benzaldehyde at 25°C afforded a mixture of intermediate 1,1-bis-(2-hydroxynaphthylphenylmethane and 14-phenyl-dibenzoxanthene while the condensation with aliphatic aldehydes at 25°C furnished the corresponding 14-alkyl-dibenzoxanthenes as the sole product. Moreover, condensation of 2-naphthol with aromatic/aliphatic aldehydes with low catalyst loading (2 mol% was greatly accelerated under microwave irradiation to afford the corresponding 14-aryl/alkyl-dibenzoxanthenes as the sole product in high yields.

  6. Degradation and mineralization of organic UV absorber compound 2-phenylbenzimidazole-5-sulfonic acid (PBSA) using UV-254 nm/H{sub 2}O{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Abdelraheem, Wael H.M. [Chemistry Department, Faculty of Science, Sohag University, Sohag 82524 (Egypt); Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012 (United States); He, Xuexiang; Duan, Xiaodi [Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012 (United States); NIREAS-International Water Research Center, University of Cyprus, Nicosia 1678 (Cyprus); Dionysiou, Dionysios D., E-mail: dionysios.d.dionysiou@uc.edu [Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012 (United States); NIREAS-International Water Research Center, University of Cyprus, Nicosia 1678 (Cyprus)

    2015-01-23

    Graphical abstract: - Highlights: • UV-254 nm/H{sub 2}O{sub 2} AOP was utilized for the degradation and mineralization of PBSA and BSA. • Promotion of k{sub obs} with [H{sub 2}O{sub 2}]{sub 0} ≤ 4 mM and inhibition at higher [H{sub 2}O{sub 2}]{sub 0} were observed. • The S and N were released and monitored as SO{sub 4}{sup 2−} and NH{sub 4}{sup +}, respectively. • Br{sup −} inhibited both the degradation and mineralization much more significantly than Cl{sup −}. • There was an increase in [NH{sub 4}{sup +}] at higher [H{sub 2}O{sub 2}]{sub 0} and its further destruction at higher UV fluence. - Abstract: Various studies have revealed the non-biodegradable and endocrine disrupting properties of sulfonated organic UV absorbers, directing people's attention toward their risks on ecological and human health and hence their removal from water. In this study, UV-254 nm/H{sub 2}O{sub 2} advanced oxidation process (AOP) was investigated for degrading a model UV absorber compound 2-phenylbenzimidazole-5-sulfonic acid (PBSA) and a structurally similar compound 1H-benzimidazole-2-sulfonic acid (BSA), with a specific focus on their mineralization. At 4.0 mM [H{sub 2}O{sub 2}]{sub 0}, a complete removal of 40.0 μM parent PBSA and 25% decrease in TOC were achieved with 190 min of UV irradiation; SO{sub 4}{sup 2−} was formed and reached its maximum level while the release of nitrogen as NH{sub 4}{sup +} was much lower (around 50%) at 190 min. Sulfate removal was strongly enhanced by increasing [H{sub 2}O{sub 2}]{sub 0} in the range of 0–4.0 mM, with slight inhibition in 4.0–12.0 mM. Faster and earlier ammonia formation was observed at higher [H{sub 2}O{sub 2}]{sub 0}. The presence of Br{sup −} slowed down the degradation and mineralization of both compounds while a negligible effect on the degradation was observed in the presence of Cl{sup −}. Our study provides important technical and fundamental results on the HO{sup ·} based degradation and

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

    Science.gov (United States)

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

    2014-10-01

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

  8. Polyacrylamido-2-methyl-1-propane sulfonic acid-grafted-natural rubber as bio-adsorbent for heavy metal removal from aqueous standard solution and industrial wastewater.

    Science.gov (United States)

    Phetphaisit, Chor Wayakron; Yuanyang, Siriwan; Chaiyasith, Wipharat Chuachuad

    2016-01-15

    Bio-adsorbent modified natural rubber (modified NR) was prepared, by placing the sulfonic acid functional group on the isoprene chain. This modification was carried out with the aim to prepare material capable to remove heavy metals from aqueous solution. The structures of modified NR materials were characterized by FT-IR and NMR spectroscopies. Thermal gravimetric analysis of modified NR showed that the initial degradation temperature of rubber decreases with increasing amount of polyacrylamido-2-methyl-1-propane sulfonic acid (PAMPS) in the structure. In addition, water uptake of the rubber based materials was studied as a function of time and content of PAMPS. The influence of the amount of PAMPS grafted onto NR, time, pH, concentration of metal ions, temperature, and regeneration were studied in terms of their influence on the adsorption of heavy metals (Pb(2+), Cd(2+) and Cu(2+)). The adsorption isotherms of Pb(2+) and Cd(2+) were fitted to the Freundlich isotherm model, while Cu(2+) was fitted to the Langmuir isotherm. However, the results from these two isotherms resulted in a similar behavior. The adsorption capacity of the modified NR for the various heavy metals was in the following order: Pb(2+)∼Cd(2+)>Cu(2+). The maximum adsorption capacities of Pb(2+), Cd(2+), and Cu(2+) were 272.7, 267.2, and 89.7 mg/g of modified rubber, respectively. Moreover, the modified natural rubber was used for the removal of metal ions in real samples of industrial effluents where the efficiency and regeneration were also investigated.

  9. Biomarkers of environmental benzene exposure

    Energy Technology Data Exchange (ETDEWEB)

    Weisel, C.; Yu, R.; Roy, A.; Georgopoulos, P. [Environmental and Occupational Health Sciences Institute, Piscataway, NJ (United States)

    1996-12-01

    Environmental exposures to benzene result in increases in body burden that are reflected in various biomarkers of exposure, including benzene in exhaled breath, benzene in blood and urinary trans-trans-muconic acid and S-phenylmercapturic acid. A review of the literature indicates that these biomarkers can be used to distinguish populations with different levels of exposure (such as smokers from nonsmokers and occupationally exposed from environmentally exposed populations) and to determine differences in metabolism. Biomarkers in humans have shown that the percentage of benzene metabolized by the ring-opening pathway is greater at environmental exposures than that at higher occupational exposures, a trend similar to that found in animal studies. This suggests that the dose-response curve is nonlinear; that potential different metabolic mechanisms exist at high and low doses; and that the validity of a linear extrapolation of adverse effects measured at high doses to a population exposed to lower, environmental levels of benzene is uncertain. Time-series measurements of the biomarker, exhaled breath, were used to evaluate a physiologically based pharmacokinetic (PBPK) model. Biases were identified between the PBPK model predictions and experimental data that were adequately described using an empirical compartmental model. It is suggested that a mapping of the PBPK model to a compartmental model can be done to optimize the parameters in the PBPK model to provide a future framework for developing a population physiologically based pharmacokinetic model. 44 refs., 3 figs., 1 tab.

  10. Novel sulfonated poly (ether ether ketone)/phosphonic acid-functionalized titania nanohybrid membrane by an in situ method for direct methanol fuel cells

    Science.gov (United States)

    Wu, Hong; Cao, Ying; Li, Zhen; He, Guangwei; Jiang, Zhongyi

    2015-01-01

    Sulfonated poly (ether ether ketone)/phosphonic acid-functionalized titania nanohybrid membranes are prepared by an in situ method using titanium tetrachloride (TiCl4) as inorganic precursor and amino trimethylene phosphonic acid (ATMP) as modifier. Phosphonic acid-functionalized titania nanoparticles with a uniform particle size of ∼50 nm are formed and dispersed homogeneously in the SPEEK matrix with good interfacial compatibility. Accordingly, the nanohybrid membranes display remarkably enhanced proton conduction property due to the incorporation of additional sites for proton transport and the formation of well-connected channels by bridging the hydrophilic domains in SPEEK matrix. The nanohybrid membrane with 6 wt. % of phosphonic acid-functionalized titania nanoparticles exhibits the highest proton conductivity of 0.334 S cm-1 at 65 °C and 100% RH, which is 63.7% higher than that of pristine SPEEK membrane. Furthermore, the as-prepared nanohybrid membranes also show elevated thermal and mechanical stabilities as well as decreased methanol permeability.

  11. Ion-exclusion chromatographic separations of C1-C6 aliphatic carboxylic acids on a sulfonated styrene-divinylbenzene co-polymer resin column with 5-methylhexanoic acid as eluent.

    Science.gov (United States)

    Ohta, Kazutoku; Towata, Atsuya; Ohashi, Masayoshi

    2003-05-16

    The application of C7 aliphatic carboxylic acids (heptanoic, 2-methylhexanoic, 5-methylhexanoic and 2,2-dimethyl-n-valeric acids) as eluents in ion-exclusion chromatography with conductimetric detection for C1-C6 aliphatic carboxylic acids (formic, acetic, propionic, isobutyric, butyric, isovaleric, valeric, isocaproic and caproic acids) was carried out using a highly sulfonated styrene-divinylbenzene co-polymer resin (TSKgel SCX) in the H+ form as a stationary phase. When using 0.05 mM sulfuric acid at pH 4.0 as the eluent, peak shapes of hydrophobic carboxylic acids (isovaleric, valeric, isocaproic and caproic acids) were tailed strongly. In contrast, when using 1 mM these C7 carboxylic acids at pH ca. 4 as the eluents, although system peaks (vacant peaks) corresponding to these C7 carboxylic acids appeared, peak shapes of these hydrophobic acids were improved drastically. Excellent simultaneous separation and relatively high sensitive conductimetric detection for these C1-C6 aliphatic carboxylic acids were achieved in 25 min on the TSKgel SCX column (150 x 6 mm I.D.) using 1 mM 5-methylhexanoic acid at pH 4.0 as the eluent.

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

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

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

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

    Institute of Scientific and Technical Information of China (English)

    Liu Yinong

    2015-01-01

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

  14. Hydrothermal synthesis and structural studies of a new coordination polymer of lanthanum(Ⅲ) with benzene-1,2,4,5-tetracarboxylic acid and 4,4'-bipyridine

    Institute of Scientific and Technical Information of China (English)

    Masoumeh Tabatabaee; Mahboubeh A. Sharif; Fatemeh Vakili; Saina Saheli

    2009-01-01

    A new lanthanum complex formulated as { (bpyH2)[La(btc)(H2O)4(NO3)]·2H2O }n (1) (btcH4=benzene-1,2,4,5-tetracarboxylic acid; bpy=4,4'-bipyridine) was hydrothermally synthesized. The complex was characterized by FT-IR spectroscopy, elemental analysis and X-ray diffraction. X-ray crystal structural analysis revealed that the compound belonged to the monoclinic space group C2/c with cell parameters a= 1.42806(7) nm, b=1.10258(5) ran, c=-1.60333(8) nm and β=101.9400(10)°. The complex was polymeric with La<Ⅲ atoms linked by four O atoms from two carboxylate groups of one benzene-1,2,4,5-tetracarboxylate. The LaⅢ atom was ten coordinated in a distorted tetracapped trigonal prism. In the crystal structure, a wide range of noncovalent interactions consisting of hydrogen bonding (of the types of O-H…O, N-H…O and C-H…O) and ion pairing interactions connected the various components into a supramolecular structure.

  15. MCM-41-SO3H as a Highly Efficient Sulfonic Acid Nanoreactor for the Rapid and Green Synthesis of Some Novel Highly Substituted Imidazoles under Solvent-Free Condition

    Institute of Scientific and Technical Information of China (English)

    Mahdavinia, Gholam Hossein; Amani, Ali Mohammad; Sepehrian, Hamid

    2012-01-01

    Nanosized MCM-41-SO3H based on ordered mesoporous silica material with a covalent sulfonic acid group was synthesized and used as acid catalyst for the new, simple, convenient and green synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetra-substituted imidazoles. Also some of synthesis products are new. Echo-friendly protocol, short reaction times, easy and quick isolation of the products and excellent yields are the main advantages of this procedure.

  16. Design, Synthesis and Crystal Structures of 6-Alkylidene-2’-Substituted Penicillanic Acid Sulfones as Potent Inhibitors of Acinetobacter baumannii OXA-24 Carbapenemase

    Science.gov (United States)

    Bou, German; Santillana, Elena; Sheri, Anjaneyulu; Beceiro, Alejandro; Sampson, Jared; Kalp, Matthew; Bethel, Christopher R.; Distler, Anne M.; Drawz, Sarah M.; Pagadala, Sundar Ram Reddy; van den Akker, Focco; Bonomo, Robert A.; Romero, Antonio; Buynak, John D.

    2010-01-01

    Class D β-lactamases represent a growing and diverse class of penicillin inactivating enzymes that are usually resistant to commercial β-lactamase inhibitors. As many such enzymes are found in multi-drug resistant (MDR) Acinetobacter baumannii and Pseudomonas aeruginosa, novel β-lactamase inhibitors are urgently needed. Five unique 6-alkylidene-2’-substituted penicillanic acid sulfones (1, 2, 3, 4, and 5) were synthesized and tested against OXA-24, a clinically important β-lactamase that inactivates carbapenems and found in A. baumannii. Based upon the roles Tyr112 and Met223 play in the OXA-24 β-lactamase, we also engineered two variants (Tyr112Ala and Tyr112Ala,Met223Ala) to test the hypothesis that the hydrophobic tunnel formed by these residues influences inhibitor recognition. IC50 values, against OXA-24, and two OXA-24 β-lactamase variants ranged from 10 ± 1 (4 vs. WT) to 338 ± 20 nM (5 vs. Tyr112Ala, Met223Ala). Compound 4 possessed the lowest Ki (500 ± 80 nM vs. WT) and 1 possessed the highest inactivation efficiency (kinact/Ki = 0.21 ± 0.02 μM-1s-1). Electrospray ionization mass spectrometry revealed a single covalent adduct, suggesting the formation of an acyl-enzyme intermediate. X-ray structures of OXA-24 complexed to four inhibitors (2.0-2.6 Å) reveal there is formation of stable bicyclic aromatic intermediates with their carbonyl oxygen in the oxyanion hole. These data provide the first structural evidence that 6-alkylidene-2’-substituted penicillin sulfones are effective mechanism-based inactivators of class D β-lactamases. Their unique chemistry makes them developmental candidates. Mechanisms for class D hydrolysis and inhibition are discussed, and a pathway for the evolution of the BlaR1 sensor of Staphylococcus aureus to the class D β-lactamases is proposed. PMID:20822105

  17. Design, synthesis, and crystal structures of 6-alkylidene-2'-substituted penicillanic acid sulfones as potent inhibitors of Acinetobacter baumannii OXA-24 carbapenemase.

    Science.gov (United States)

    Bou, German; Santillana, Elena; Sheri, Anjaneyulu; Beceiro, Alejandro; Sampson, Jared M; Kalp, Matthew; Bethel, Christopher R; Distler, Anne M; Drawz, Sarah M; Pagadala, Sundar Ram Reddy; van den Akker, Focco; Bonomo, Robert A; Romero, Antonio; Buynak, John D

    2010-09-29

    Class D β-lactamases represent a growing and diverse class of penicillin-inactivating enzymes that are usually resistant to commercial β-lactamase inhibitors. As many such enzymes are found in multi-drug resistant (MDR) Acinetobacter baumannii and Pseudomonas aeruginosa, novel β-lactamase inhibitors are urgently needed. Five unique 6-alkylidene-2'-substituted penicillanic acid sulfones (1-5) were synthesized and tested against OXA-24, a clinically important β-lactamase that inactivates carbapenems and is found in A. baumannii. Based upon the roles Tyr112 and Met223 play in the OXA-24 β-lactamase, we also engineered two variants (Tyr112Ala and Tyr112Ala,Met223Ala) to test the hypothesis that the hydrophobic tunnel formed by these residues influences inhibitor recognition. IC(50) values against OXA-24 and two OXA-24 β-lactamase variants ranged from 10 ± 1 (4 vs WT) to 338 ± 20 nM (5 vs Tyr112Ala, Met223Ala). Compound 4 possessed the lowest K(i) (500 ± 80 nM vs WT), and 1 possessed the highest inactivation efficiency (k(inact)/K(i) = 0.21 ± 0.02 μM(-1)  s(-1)). Electrospray ionization mass spectrometry revealed a single covalent adduct, suggesting the formation of an acyl-enzyme intermediate. X-ray structures of OXA-24 complexed to four inhibitors (2.0-2.6 Å) reveal the formation of stable bicyclic aromatic intermediates with their carbonyl oxygen in the oxyanion hole. These data provide the first structural evidence that 6-alkylidene-2'-substituted penicillin sulfones are effective mechanism-based inactivators of class D β-lactamases. Their unique chemistry makes them developmental candidates. Mechanisms for class D hydrolysis and inhibition are discussed, and a pathway for the evolution of the BlaR1 sensor of Staphylococcus aureus to the class D β-lactamases is proposed.

  18. Properties investigation of sulfonated poly(ether ether ketone)/polyacrylonitrile acid-base blend membrane for vanadium redox flow battery application.

    Science.gov (United States)

    Li, Zhaohua; Dai, Wenjing; Yu, Lihong; Liu, Le; Xi, Jingyu; Qiu, Xinping; Chen, Liquan

    2014-11-12

    Acid-base blend membrane prepared from sulfonated poly(ether ether ketone) (SPEEK) and polyacrylonitrile (PAN) was detailedly evaluated for vanadium redox flow battery (VRFB) application. SPEEK/PAN blend membrane exhibited dense and homogeneous cross-section morphology as scanning electron microscopy and energy-dispersive X-ray spectroscopy images show. The acid-base interaction of ionic cross-linking and hydrogen bonding between SPEEK and PAN could effectively reduce water uptake, swelling ratio, and vanadium ion permeability, and improve the performance and stability of blend membrane. Because of the good balance of proton conductivity and vanadium ion permeability, blend membrane with 20 wt % PAN (S/PAN-20%) showed higher Coulombic efficiency (96.2% vs 91.1%) and energy efficiency (83.5% vs 78.4%) than Nafion 117 membrane at current density of 80 mA cm(-2) when they were used in VRFB single cell. Besides, S/PAN-20% membrane kept a stable performance during 150 cycles at current density of 80 mA cm(-2) in the cycle life test. Hence the SPEEK/PAN acid-base blend membrane could be used as promising candidate for VRFB application.

  19. An 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)-immobilized electrode for the simultaneous detection of dopamine and uric acid in the presence of ascorbic acid.

    Science.gov (United States)

    Chih, Yi-Kai; Yang, Ming-Chang

    2013-06-01

    An 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS)-immobilized carbon nanotube (CNT) electrode was used to simultaneously detect dopamine (DA) and uric acid (UA) in the presence of ascorbic acid (AA) with differential pulse voltammetry. When ABTS was immobilized onto the CNT electrode in the presence of DA, UA and 100 μM AA, the sensitivity to DA increased from 0.600 (±0.013) to 1.334 (±0.010) μA/μM in the concentration ranges of 0.90-10 μM and 1.87-20 μM, respectively, and the sensitivity to UA increased from 0.030 (±0.005) to 0.078 (±0.006) μA/μM in the concentration ranges of 2.16-240 μM and 3.07-400 μM, respectively. These findings demonstrate that the ABTS-immobilized CNT electrode attained a higher sensitivity to UA and also a wider linear range of concentrations.

  20. 对氨基苯磺酸催化合成水杨酸正丁酯%Synthesis of butyl salicylate catalyzed by p-aminobenzene sulfonic acid

    Institute of Scientific and Technical Information of China (English)

    赵卫星; 姜红波

    2013-01-01

    以正丁醇与水杨酸为原料,采用对氨基苯磺酸为催化剂,通过酯化反应合成了水杨酸正丁酯.考察了酸醇物质的量比、催化剂用量、反应时间对水杨酸正丁酯化收率的影响.结果表明,在回流条件下,当水杨酸的加入量0.20 mol,正丁醇的加入量0.32 mol,即酸与醇物质的量比为1∶1.6,催化剂对氨基苯磺酸用量为0.70 g(相当于5%的酸),反应4.0h时,水杨酸正丁酯收率可达到72.90%.%Synthesis of butyl salicylate from 2-hydroxybenzoic acid and n-butanol catalyzed by p-aminobenzene sulfonic acid was studied.The effects of the molar ratio of 2-hydroxybenzoic acid to n-butanol,the amount of catalyst and the reaction time on the yield was discussed.The results show that when the molar ratio of 2-hydroxybenzoic acid (0.20 mol) to n-butanol (0.32 mol) was 1 ∶ 1.6;the amount of catalyst was 0.70 g (5%,with respect to 2-hydroxybenzoic acid) and the reaction time was 4.0 h under reflux,the yield of butyl salicylate reached 72.90%.

  1. 以弱碱性树脂去除废水中5-氨基-2-氯苯-4-磺酸和盐酸%Removal of 5-Amino-2-chlorotoluene-4-sulfonic and Chlorhydric Acids from Wastewater by Weakly Basic Resin

    Institute of Scientific and Technical Information of China (English)

    李长海; 许振良; 李春平

    2006-01-01

    This research deals with an investigation of the adsorption of two acids, namely, 5-amino-2-chlorotoluene-4-sulfonic and chlorhydric acids from their solution onto weakly basic resin. The screening of resins, kinetics, and isotherm were studied. The results indicate that the D301R is more appropriate for the removal of acids from solution. The adsorption of acids obeys Langmuir isotherm and the first-order kinetics model. Sorptive affinity of the two acids on D301R was found to be in the order of 5-amino-2-chlorotoluene-4-sulfonic acid>chlorhydric acid. Thermodynamic parameters for the adsorption of acids were calculated and discussed. The maximum removal of acids was observed around 97% and 76% at 25℃ for 5-amino-2-chlorotoluene-4-sulfonic acid and chlorhydric acid, respectively.

  2. Mesoporous silica materials with an extremely high content of organic sulfonic groups and their comparable activities with that of concentrated sulfuric acid in catalytic esterification.

    Science.gov (United States)

    Feng, Ye-Fei; Yang, Xiao-Yu; Di, Yan; Du, Yun-Chen; Zhang, Yong-Lai; Xiao, Feng-Shou

    2006-07-27

    Mesoporous silica materials (HS-JLU-20) with an extremely high content of mercaptopropyl groups have been successfully synthesized using fluorocarbon-hydrocarbon surfactant mixtures through a simple co-condensation approach of tetraethyl orthosilicate (TEOS) and (3-mercaptopropyl)trimethoxysilane (MPTS), which are characterized by X-ray diffraction (XRD), nitrogen adsorption and desorption isotherms, transmission electron microscopy (TEM), CHNS elemental analysis, thermogravimetry analysis (TGA), and (29)Si NMR spectroscopy. The results show that HS-JLU-20 samples with molar ratios of MPTS/(MPTS + TEOS) at 0.5-0.8 in the starting synthetic gels still show their mesostructures, while HS-SBA-15 with the molar ratio of MPTS/(MPTS + TEOS) at 0.50 completely loses its mesostructure in the absence of fluorocarbon surfactant. Possibly, fluorocarbon surfactant containing N(+) species with a positive charge could effectively interact with negatively charged mercapto groups in the synthesis of HS-JLU-20 materials, resulting in the formation of mesoporous silicas with good cross-linking of silica condensation even at an extremely high content of organic mercapto groups. More interestingly, after the treatment with hydrogen peroxide, HSO(3)-JLU-20 materials with an extremely high content of organic sulfonic groups exhibit comparable activity with liquid concentrated sulfuric acid in catalytic esterification of cyclohexanol with acetic acid.

  3. Presence of UV filters in surface water and the effects of phenylbenzimidazole sulfonic acid on rainbow trout (Oncorhynchus mykiss) following a chronic toxicity test.

    Science.gov (United States)

    Grabicova, Katerina; Fedorova, Ganna; Burkina, Viktoriia; Steinbach, Christoph; Schmidt-Posthaus, Heike; Zlabek, Vladimir; Kocour Kroupova, Hana; Grabic, Roman; Randak, Tomas

    2013-10-01

    UV filters belong to a group of compounds that are used by humans and are present in municipal waste-waters, effluents from sewage treatment plants and surface waters. Current information regarding UV filters and their effects on fish is limited. In this study, the occurrence of three commonly used UV filters - 2-phenylbenzimidazole-5-sulfonic acid (PBSA), 2-hydroxy-4-methoxybenzophenone (benzophenone-3, BP-3) and 5-benzoyl-4-hydroxy-2-methoxy-benzenesulfonic acid (benzophenone-4, BP-4) - in South Bohemia (Czech Republic) surface waters is presented. PBSA concentrations (up to 13μgL(-1)) were significantly greater than BP-3 or BP-4 concentrations (up to 620 and 390ngL(-1), respectively). On the basis of these results, PBSA was selected for use in a toxicity test utilizing the common model organism rainbow trout (Oncorhynchus mykiss). Fish were exposed to three concentrations of PBSA (1, 10 and 1000µgL(-1)) for 21 and 42 days. The PBSA concentrations in the fish plasma, liver and kidneys were elevated after 21 and 42 days of exposure. PBSA increased activity of certain P450 cytochromes. Exposure to PBSA also changed various biochemical parameters and enzyme activities in the fish plasma. However, no pathological changes were obvious in the liver or gonads.

  4. Electrochemical sensor based on molecularly imprinted film at polypyrrole-sulfonated graphene/hyaluronic acid-multiwalled carbon nanotubes modified electrode for determination of tryptamine.

    Science.gov (United States)

    Xing, Xianrong; Liu, Su; Yu, Jinghua; Lian, Wenjing; Huang, Jiadong

    2012-01-15

    An imprinted electrochemical sensor based on polypyrrole-sulfonated graphene (PPy-SG)/hyaluronic acid-multiwalled carbon nanotubes (HA-MWCNTs) for sensitive detection of tryptamine was presented. Molecularly imprinted polymers (MIPs) were synthesized by electropolymerization using tryptamine as the template, and para-aminobenzoic acid (pABA) as the monomer. The surface feature of the modified electrode was characterized by cyclic voltammetry (CV). The proposed sensor was tested by chronoamperometry. Several important parameters controlling the performance of the molecularly imprinted sensor were investigated and optimized. The results showed that the PPy-SG composites films showed improved conductivity and electrochemical performances. HA-MWCNTs bionanocomposites could enhance the current response evidently. The good selectivity of the sensor allowed three discriminations of tryptamine from interferents, which include tyramine, dopamine and tryptophan. Under the optimal conditions, a linear ranging from 9.0×10(-8) mol L(-1) to 7.0×10(-5) mol L(-1) for the detection of tryptamine was observed with the detection limit of 7.4×10(-8) mol L(-1) (S/N=3). This imprinted electrochemical sensor was successfully employed to detect tryptamine in real samples.

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

    Science.gov (United States)

    2008-12-01

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

  6. 侧链含有全氟磺酸的聚芳醚砜质子交换膜材料的制备及性能%Synthesis and Properties of Poly (aryl ether sulfones) Functionalized with Pendant Perfluoroalkyl Sulfonic Acid for Proton Exchange Membrane

    Institute of Scientific and Technical Information of China (English)

    王永鹏; 岳喜贵; 庞金辉; 李雪峰; 李娜; 张海博; 姜振华

    2012-01-01

    A novel poly(arylene ether sulfone) with a perfluoroalkyl sulfonic acid pendant ( PES-PSA) was synthesized by Ullman coupling of poly {oxy-4,4'-[2-(4'-bromophenyl ene)biphenylene]oxy-4,4'-diphenyl-sulfone 1 (PES-Br) and potassium 1,1,2,2-tetrafluoro-2-(l ,1,2,2-tetiafluoro-2-iodo-ethoxy)ethane9ulfonate ( PSA-K). The introduction of the perfluoroalkyl sulfonic acids was successfully carried out with high conversion (c. a. 50% ) to yield the desired polymer. Even with a low ion exchange capacity(IEC) of 0.907 meq. / g, PES-PSA exhibited a high proton conductivity of 0.039 S/cm at 80 ℃ under 100% relative humidity. The low IEC makes the membrane own good dimensional stability and thermal stability. Other membrane properties , such as thermal properties and water uptake were also investigated in detail.%利用含溴苯侧基的聚芳醚砜( PES-Br)和1,1,2,2-四氟-2-(1,1,2,2-四氟-2-碘乙氧基)乙烷磺酸钾(PSA-K)进行Ullman偶联反应,制备了新型含全氟磺酸侧链的聚芳醚砜(PES-PSA),全氟磺酸的引入量为50%.在离子交换容量(IEC)为0.907 meq./g,80℃,相对湿度为100%时,PES-PSA质子传导率达到0.039S/cm,表现出较高的质子传导能力.其较低的IEC值使膜材料表现出良好的热稳定性和尺寸稳定性.

  7. 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.

  8. DFT study on the effect of gallic acid on adsorption of benzene by resin%DFT方法研究没食子酸对树脂吸附苯的影响

    Institute of Scientific and Technical Information of China (English)

    于海艳; 费正皓

    2011-01-01

    In this paper, the molecular structures for DFT study were full optimited by the B3LYP method using the 6-311 ++ G** basis set,in both the gaseous and aqueous phases, and the PCM solvate theory model was employed for aqueous solution calculations. The hydrogen bonds, formed between the molecules of gallic acid and the molecules of water or benzene, were studied by DFT method, and then the effects on adsorption of gallic acid and benzene by resin were discussed. The calculation results indicated that one hydroxyl group in gallic acid molecule could form two hydrogen bonds not only with benzene molecule but also with water molecule leading to its great hydrophilicity. The hydrogen bonds between molecules of gallic acid and benzene are stronger than those between molecules of water and benzene, which induces the significant effects on adsorption of benzene by resin deriving from the presence of gallic acid. On the other hand, the solvent effect could influence the adsorption of gallic acid and/or benzene by resin.%用密度泛函B3LYP/6-311 ++ G**理论,气相和水相中(PCM溶剂模型应用于水相计算),对所研究物种进行全自由度优化,通过研究没食子酸与水或苯分子间的氢键作用,探讨树脂对没食子酸及苯吸附的影响.计算结果显示,没食子酸的羟基不仅与水分子能形成双聚氢键,显示极强的亲水性;且与苯分子亦可形成双氢键,其作用力强于苯分子与水分子间的作用力,没食子酸的存在显著影响树脂吸附苯.同时,溶剂化效应对树脂吸附没食子酸和苯具有一定的影响.

  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. 苯与双氧水在高效钼钒磷杂多酸催化剂上的羟基化%Hydroxylation of Benzene with Hydrogen Peroxide over Highly Efficient Molybdovanadophosphoric Heteropoly Acid Catalysts

    Institute of Scientific and Technical Information of China (English)

    张富民; 郭麦平; 葛汉青; 王军

    2007-01-01

    Keggin type molybdovanadophosphoric heteropoly acids,H3+nPMo12-nVnO40 (n= 1-3),were prepared by a novel environmentally benign method,and their catalytic performances were evaluated via hydroxylation of benzene to phenol with hydrogen peroxide as oxidant in a mixed solvent of glacial acetic acid and acetonitrile.Various reaction parameters,such as reaction time,reaction temperature,ratio of benzene to hydrogen peroxide,concentration of aqueous hydrogen peroxide,ratio of glacial acetic acid to acetonitrile in solvent and catalyst concentration,were changed to obtain an optimal reaction conditions. H3+nPMo12-nVnO40 (n= 1-3) are revealed to be highly efficient catalyst for hydroxylation of benzene. In case of H5PMo10V2O40,a conversion of benzene of 34.5% with the selectivity of phenol of 100% can be obtained at the optimal reaction conditions.

  11. Visceral hypersensitivity is provoked by 2,4,6-trinitrobenzene sulfonic acid-induced ileitis in rats

    Directory of Open Access Journals (Sweden)

    Manoj Kumar Shah

    2016-07-01

    Full Text Available Background and Aims: Crohn’s Disease (CD, a chronic Inflammatory Bowel Disease, can occur in any part of the gastrointestinal tract, but most frequently in the ileum. Visceral hypersensitivity contributes for development of chronic abdominal pain in this disease. Currently, the understanding of the mechanism underlying hypersensitivity of Crohn’s ileitis has been hindered by a lack of specific animal model. The present study is undertaken to investigate the visceral hypersensitivity provoked by 2,4,6-trinitrobenzene sulfonic (TNBS-induced ileitis rats.Methods: Male Sprague-Dawley rats were anaesthetized and laparotomized for intraileal injection of TNBS (0.6 ml, 80 mg/kg body weight in 30% ethanol, n = 48, an equal volume of 30% Ethanol (n = 24 and Saline (n = 24, respectively. Visceral hypersensitivity was assessed by visceromotor responses (VMR to 20, 40, 60, 80 and 100 mmHg colorectal distension pressure (CRD at day 1, 3, 7, 14, 21 and 28. Immediately after CRD test, the rats were euthanized for collecting the terminal ileal segment for histopathological examinations and ELISA of myleoperoxidase and cytokines (TNF-α, IL-1β, IL-6, and dorsal root ganglia (T11 for determination of calcitonin gene-related peptide by immunohistochemistry, respectively. Results: Among all groups, TNBS-treatment showed transmural inflammation initially at 3 days, reached maximum at 7 days and persisted up to 21 days. The rats with ileitis exhibited (P < 0.05 VMR to CRD at day 7 to day 21. The calcitonin gene-related peptide-immunoreactive positive cells increased (P < 0.05 in dorsal root ganglia at day 7 to 21, which was persistently consistent with visceral hypersensitivity in TNBS-treated rats.Conclusions: TNBS injection into the ileum induced transmural ileitis including granuloma and visceral hypersensitivity. As this model mimics clinical manifestations of CD, it may provide a road map to probe the pathogenesis of gut inflammation and visceral

  12. Synthesis of benzo[g]indeno[2,1-b]quinoline derivatives via four-component and one-pot synthesis in presence of 3-methyl-1-sulfonic acid imidazolium hydrogen sulfate

    Institute of Scientific and Technical Information of China (English)

    Nader Ghaffari Khaligh

    2014-01-01

    A simple and facile synthesis of 12-arylbenzo[g]indeno[2,1-b]quinoline-6,11,13-trione deriv-atives was accomplished by the one-pot condensation of 2-hydroxynaphthalene-1,4-dione, aryl aldehydes, 2H-indene-1,3-dione, and ammonium acetate under solvent-free conditions in the presence of a Brönsted ionic liquid catalyst, namely 3-methyl-1-sulfonic acid imidazolium hydrogen sulfate.

  13. Cross-coupling reaction of cy- clopropylboronic acids with a- ryl w-halo-oxo-perfluoroalkyl- sulfonates

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The cross-coupling reaction of cyclopropylboronic acids with aryl w-halo-oxo-perfluoroalkylsulfonates is investigated. It was found that the stereodefined cyclopropylboronic acids can readily react with aryl w-halo-oxo- perfluoroalkylsulfonates to give the corresponding cross- coupling products in high yields under the appropriate con-ditions and in the presence of transition metal catalysts. For the reaction of various aryl perfluoroalkylsulfonates bearing the substituents, the use of corresponding bases was essential. During these reactions, the cyclopropyl configurations of cyclopropylboronic acids are retained. Thus, the procedure provides a new convenient route to stereodefined cyclopro-pane derivatives from phenols and commerce-available w-chloro-oxo-perfluoroalkylsulfonyl fluoride.

  14. Syntheses, structures and fluorescence properties of cadmium coordination polymers with triangular 1,3-bis[2-(4‧-pyridyl)ethenyl]benzene and linear dicarboxylic acids

    Science.gov (United States)

    Liang, Rui; Yue, Fangfang; Wang, Yuting; Guo, Yongkang; Xuan, Xiaopeng

    2016-09-01

    Three new polymeric complexes [Cd3(1,3-BPEB)3(1,4-BDC)3·2H2O]n (1), [Cd2(1,3-BPEB)2(4,4‧-BPDC)2]n (2) and [Cd2(1,3-BPEB)2(4,4‧-STDC)2]n (3) (1,3-BPEB = 1,3-bis[2-(4‧-pyridyl)ethenyl]benzene, 1,4-BDC = 1,4-benzenedicarboxylic acid, 4,4‧-BPDC = 4,4‧-biphenyldicarboxylic acid and 4,4‧-STDC = 4,4‧-stilbenedicarboxylic acid) have been prepared by the solvothermal reaction of 1,3-BPEB, Cd(NO3)2·4H2O and dicarboxylic acids. Single-crystal X-ray diffraction reveals that these complexes have novel complicated structures. Complex 1 is a 3-D network structure by linking Cd atoms with 1,4-BDC and 1,3-BPEB ligands. Complex 2 shows a 3-D interpenetrating layered structure formed by three networks which derived from bridged Cd atoms with 4,4‧-BPDC and 1,3-BPEB ligands. Complex 3 has a fivefold interpenetrating 3-D coordination framework by linking Cd atoms with 4,4‧-STDC and 1,3-BPEB ligands. The dicarboxylic acids afford different coordination modes to bind Cd atoms in these three complexes. Additionally, these compounds were further characterized by PXRD, FT-IR spectroscopy and thermogravimetric (TG) analysis. Their fluorescence spectra were also determined and analyzed in the solid state at room temperature.

  15. The Effect of Monosodium Glutamate (MSG On Rat Liver And The Ameliorating Effect Of "Guanidino Ethane Sulfonic acid (GES" (Histological, Histochemical and Electron Microscopy Studies

    Directory of Open Access Journals (Sweden)

    Hanaa F. Waer and *Saleh Edress

    2006-09-01

    Full Text Available Food additives are chemical substances added intentionally to food stuffs to preserve, color, sweeten and flavor food. Monosodium glutamate (MSG is used as a flavor enhancer and found in most soups, salad dressing and processed meat. The use of MSG in food is growing. Irrational fear had increased in the last few years due to the adverse reactions and toxicity of MSG. The present study was designed to investigate the effect of MSG on the rat liver and the ameliorating effect of taurine analog "Guanidinoethane sulfonic acid (GES". Sixty albino rats (2-3 months old were used in the present study. MSG was given orally at a daily dose of 60 mg/1000 g for one month, two months and was given at a daily dose of 100mg/1000gm for one month. The results revealed that the deleterious effects of MSG were dose related and cumulative. In MSG treated rats, the examined sections showed remarkable alterations varied considerably from moderate structural changes to cytoplasmic lysis and signs of degeneration of cellular organelles. The histological changes showed disturbed liver architecture, hemorrhage in the central veins, areas of necrosis, vacuolation and increased inflammatory cells infiltration. The glycogen granules increased as well as the collagen fibers in the liver cells. Ultrastructural changes showed loss of cytoplasmic differentiation, vacuolation, pyknotic nuclei with irregular nuclear membranes and elongated electron dense mitochondria. Conversely, treatment of rats with taurine analog (GES significantly attenuated the cellular toxicity of MSG.

  16. Therapeutic effects of human amnion-derived mesenchymal stem cell transplantation and conditioned medium enema in rats with trinitrobenzene sulfonic acid-induced colitis

    Science.gov (United States)

    Miyamoto, Shuichi; Ohnishi, Shunsuke; Onishi, Reizo; Tsuchiya, Ikuki; Hosono, Hidetaka; Katsurada, Takehiko; Yamahara, Kenichi; Takeda, Hiroshi; Sakamoto, Naoya

    2017-01-01

    Cell therapy with mesenchymal stem cells (MSCs) is expected to provide a new strategy for the treatment of inflammatory bowel disease (IBD). Large amounts of MSCs can be obtained from human amnion. Therefore, we investigated the effect of transplantation of human amnion-derived MSCs (hAMSCs) or enema of conditioned medium (CM) from hAMSCs into rats with 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. In the first experiment, 10-week-old male Sprague-Dawley rats were intravenously injected with hAMSCs (1 × 106 cells) 3 h after rectal administration of TNBS (45 mg/kg). In the second experiment, rats with TNBS-induced colitis received CM by enema into the colon for 3 days. Colitis was investigated by endoscopy, histology, immunohistochemistry, and by measuring mRNA expression of inflammatory mediators. Administration of hAMSCs or CM enema significantly improved the endoscopic score. In addition, these two interventions resulted in significantly decreased infiltration of neutrophils and monocytes/macrophages and decreased expression levels of TNF-α, CXCL1, and CCL2. In conclusion, transplantation of hAMSCs and CM enema provided significant improvement in rats with TNBS-induced colitis. CM from hAMSCs and hAMSCs may be new strategies for the treatment of IBD.

  17. Electrodeposition of manganese dioxide in three-dimensional poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid)-polyaniline for supercapacitor

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Feng-Jiin [Department of Chemical Engineering, National United University, 1 Lien Da, Kung-Ching Li, Miao-Li (China)

    2008-07-15

    The preparation of composites of precise metal oxides/conducting polymers is important in studies of supercapacitors. In this work, a three-dimensional matrix of poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid)-polyaniline (PEDOT-PSS-PANI) was prepared by interfacial polymerization of ANI into PEDOT-PSS. Conductivity was enhanced by incorporating of PANI into PEDOT-PSS because of the decrease in the distance for electron shuttling along the conjugated polymeric chain. Composite electrodes were prepared by the electrodeposition of manganese dioxide (MnO{sub 2}) in a PEDOT-PSS-PANI three-dimensional matrix. The electrodes were characterized by field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry techniques. The results show a significant improvement in the specific capacitance of the composite electrode. For PEDOT-PSS the specific capacitance was of 0.23 F g{sup -1}, while PEDOT-PSS-PANI and PEDOT-PSS-PANI-MnO{sub 2} displayed values of 6.7 and 61.5 F g{sup -1}, respectively. When only considering the MnO{sub 2} mass, the composite had the specific capacitance of 372 F g{sup -1}. The composite also had an excellent cyclic performance. (author)

  18. Simultaneous determination of caffeine and paracetamol by square wave voltammetry at poly(4-amino-3-hydroxynaphthalene sulfonic acid)-modified glassy carbon electrode.

    Science.gov (United States)

    Tefera, Molla; Geto, Alemnew; Tessema, Merid; Admassie, Shimelis

    2016-11-01

    Poly(4-amino-3-hydroxynaphthalene sulfonic acid)-modified glassy carbon electrode (poly(AHNSA)/GCE) was prepared for simultaneous determination of caffeine and paracetamol using square-wave voltammetry. The method was used to study the effects of pH and scan rate on the voltammetric response of caffeine and paracetamol. Linear calibration curves in the range of 10-125μM were obtained for both caffeine and paracetamol in acetate buffer solution of pH 4.5 with a correlation coefficient of 0.9989 and 0.9986, respectively. The calculated detection limits (S/N=3) were 0.79μM for caffeine and 0.45μM for paracetamol. The effects of some interfering substances in the determination of caffeine and paracetamol were also studied and their interferences were found to be negligible which proved the selectivity of the modified electrode. The method was successfully applied for the quantitative determination of caffeine and paracetamol in Coca-Cola, Pepsi-Cola and tea samples.

  19. DMFC Performance of Polymer Electrolyte Membranes Prepared from a Graft-Copolymer Consisting of a Polysulfone Main Chain and Styrene Sulfonic Acid Side Chains

    Directory of Open Access Journals (Sweden)

    Nobutaka Endo

    2016-08-01

    Full Text Available Polymer electrolyte membranes (PEMs for direct methanol fuel cell (DMFC applications were prepared from a graft-copolymer (PSF-g-PSSA consisting of a polysulfone (PSF main chain and poly(styrene sulfonic acid (PSSA side chains with various average distances between side chains (Lav and side chain lengths (Lsc. The polymers were synthesized by grafting ethyl p-styrenesulfonate (EtSS on macro-initiators of chloromethylated polysulfone with different contents of chloromethyl (CM groups, and by changing EtSS content in the copolymers by using atom transfer radical polymerization (ATRP. The DMFC performance tests using membrane electrode assemblis (MEAs with the three types of the PEMs revealed that: a PSF-g-PSSA PEM (SF-6 prepared from a graft copolymer with short average distances between side chains (Lav and medium Lsc had higher DMFC performance than PEMs with long Lav and long Lsc or with short Lav and short Lsc. SF-6 had about two times higher PDmax (68.4 mW/cm2 than Nafion® 112 at 30 wt % of methanol concentration. Furthermore, it had 58.2 mW/cm2 of PDmax at 50 wt % of methanol concentration because of it has the highest proton selectivity during DMFC operation of all the PSF-g-PSSA PEMs and Nafion® 112.

  20. A targeted/non-targeted screening method for perfluoroalkyl carboxylic acids and sulfonates in whole fish using quadrupole time-of-flight mass spectrometry and MS(e).

    Science.gov (United States)

    Crimmins, Bernard S; Xia, Xiaoyan; Hopke, Philip K; Holsen, Thomas M

    2014-02-01

    A new method for measuring perfluoroalkyl contaminants (PFCs) in biological matrices has been developed. An ultra-high pressure liquid chromatograph equipped with a quadrupole time-of-flight mass spectrometer (UPLC-QToF) was optimized using a continuous precursor/product ion monitoring mode. Unlike traditional targeted studies that isolate precursor/product ion pairs, the current method alternates between two ionization energy channels to continuously capture standard electrospray ionization (low energy) and collision induced dissociation (high energy) spectra. The result is the indiscriminant acquisition of paired low and high energy spectra for all constituents eluting from the chromatographic system. This technique was evaluated for the routine analysis of perfluoroalkyl species. Using this technique, linear perfluoroalkyl carboxylic acids (C4 to C14) and perfluoroalkyl sulfonates (C4, C6, C8 and C10) exhibited a linear range spanning over three orders of magnitude and were detectable at levels less than 1 pg on column with a root mean squared signal to noise ratio of 5 to 20. Lake trout (Salvelinus namaycush) and National Institutes of Standards and Technology Standard Reference Material 1946 were used to evaluate matrix effects and the accuracy of this method when applied to a whole fish extract. The current method was also evaluated as a diagnostic tool to identify unknown PFCs using experimental fragmentation patterns, mass defect filtering and Kendrick plots.

  1. Appropriateness of reference genes for normalizing messenger RNA in mouse 2,4-dinitrobenzene sulfonic acid (DNBS)-induced colitis using quantitative real time PCR

    Science.gov (United States)

    Eissa, Nour; Kermarrec, Laëtitia; Hussein, Hayam; Bernstein, Charles N.; Ghia, Jean-Eric

    2017-01-01

    2,4-Dinitrobenzene sulfonic acid (DNBS)-induced colitis is an experimental model that mimics Crohn’s disease. Appropriateness of reference genes is crucial for RT-qPCR. This is the first study to determine the stability of reference gene expression (RGE) in mice treated with DNBS. DNBS experimental Colitis was induced in male C57BL/6 mice. RNA was extracted from colon tissue and comprehensive analysis of 13 RGE was performed according to predefined criteria. Relative colonic TNF-α and IL-1β mRNA levels were calculated. Colitis significantly altered the stability of mucosal RGE. Commonly used glyceraldehyde-3-phosphate dehydrogenase (Gapdh), β-actin (Actb), or β2-microglobulin (β2m) showed the highest fluctuation within the inflamed and control groups. Conversely, ribosomal protein large P0 (Rplp0), non-POU domain containing (Nono), TATA-box-binding protein (Tbp) and eukaryotic translation elongation factor 2 (Eef2) were not affected by inflammation and were the most stable genes. TNF-α and IL-1β mRNA levels was dependent on the reference gene used and varied from significant when the most stable genes were used to non-significant when the least stable genes were used. The appropriate choice of RGE is critical to guarantee satisfactory normalization of RT-qPCR data when using DNBS-Model. We recommend using Rplp0, Nono, Tbp, Hprt and Eef2 instead of common reference genes. PMID:28186172

  2. Sensitive and selective colorimetric detection of glutathione in human plasma with 2,2‧-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and Ag+ ion

    Science.gov (United States)

    Li, Yinhuan; Liu, Xiaoying; Zhang, Ruyi

    2017-02-01

    Glutathione is of vital importance to human beings through involving in many cellular functions. Simple and sensitive methods capable of detecting glutathione in biological samples are significant to diagnosis and prevention of disease. Here a simple, label-free, and sensitive colorimetric method was developed for the determination of glutathione. It was observed that Ag+ ion could directly oxidize 2,2‧-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), a commonly used peroxidase substrate, to produce a green solution, which possessed a maximum absorbance at 420 nm. The presence of glutathione hindered the oxidation process and decreased the absorbance at 420 nm owing to its ability to bind with Ag+ ion. The procedure allowed the measurement of 0.1-4.0 μM glutathione with a detection limit of 59 nM. The relative standard deviation was 1.8% in eleven replicated measurements of 1.0 μM glutathione solution. The method was applied to the determination of glutathione in human plasma with satisfactory results.

  3. The Antidotal Effects of High-dosage γ-Aminobutyric Acid on Acute Tetramine Poisoning as Compared with Sodium Dimercaptopropane Sulfonate

    Institute of Scientific and Technical Information of China (English)

    SUN Peng; HAN Jiyuan; WENG Yuying

    2007-01-01

    To investigate the therapeutic effect of high-dosage γ-aminobutyric acid (GABA) on acute tetramine (TET) poisoning, 50 Kunming mice were divided into 5 groups at random and the antidotal effects of GABA or sodium dimercaptopropane sulfonate (Na-DMPS) on poisoned mice in different groups were observed in order to compare the therapeutic effects of high-dosage GABA with those of Na-DMPS. Slices of brain tissue of the poisoned mice were made to examine pathological changes of cells. The survival analysis was employed. Our results showed that both high-dosage GABA and Na-DMPS could obviously prolong the survival time, delay onset of convulsion and muscular twitch, and ameliorate the symptoms after acute tetramine poisoning in the mice.Better effects could be achieved with earlier use of high dosage GABA or Na-DMPS. There was no significant difference in prolonging the survival time between high-dose GABA and Na-DMPS used immediately after poisioning. It is concluded that high-dosage GABA can effectively antagonize acute toxicity of teramine in mice. And it is suggested that high-dosage GABA may be used as an excellent antidote for acute TET poisoning in clinical practice. The indications and correct dosage for clinical use awaits to be further studied.

  4. Perfluorooctane sulfonic acid in bib (Trisopterus luscus) and plaice (Pleuronectes platessa) from the Western Scheldt and the Belgian North Sea: distribution and biochemical effects.

    Science.gov (United States)

    Hoff, Philippe T; Van de Vijver, Kristin; Van Dongen, Walter; Esmans, Eddy L; Blust, Ronny; De Coen, Wim M

    2003-03-01

    A biomonitoring campaign was conducted in the Belgian North Sea and in the Western Scheldt (The Netherlands) with the primary goal to assess perfluorooctane sulfonic acid (PFOS) contamination and distribution in different biota. This study covers the results obtained for bib (Trisopterus luscus) and plaice (Pleuronectes platessa) and includes the assessment of some stress-related biochemical endpoints. Analysis of liver and muscle PFOS concentrations of both species provided evidence for the existence of a PFOS pollution gradient along the Western Scheldt with higher levels at the upstream locations and a lower degree of PFOS pollution at the marine locations. Cellular necrosis was studied by measuring aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels in the serum. Serum ALT but not serum AST was shown to correlate positively with the PFOS liver concentration in bib (r = 0.44, p bib in the area of study. Analysis of total carbohydrate, lipid, and protein content of bib liver tissue revealed a positive correlation between the protein content and the PFOS liver concentration (r = 0.55, p < 0.01). Whether this is due to induction of compensatory mechanisms, detoxification, or repair processes remains unclear.

  5. Investigation of the Effects of Perfluorooctanoic Acid (PFOA and Perfluorooctane Sulfonate (PFOS on Apoptosis and Cell Cycle in a Zebrafish (Danio rerio Liver Cell Line

    Directory of Open Access Journals (Sweden)

    Yuan Cui

    2015-12-01

    Full Text Available This study aimed to explore the effects of perfluorooctanoic acid (PFOA and perfluorooctane sulfonate (PFOS on apoptosis and cell cycle in a zebrafish (Danio rerio liver cell line (ZFL. Treatment groups included a control group, PFOA-IC50, PFOA-IC80, PFOS-IC50 and PFOS-IC80 groups. IC50 and IC80 concentrations were identified by cellular modeling and MTT assays. mRNA levels of p53, Bcl-2, Bax, Caspase-3 and NF-κB p65 were detected by qPCR. Cell apoptosis and cell cycle were detected by flow cytometry and the protein levels of p53, Bcl-2, Bax, Caspase-3 and NF-κB p65 were determined by western blotting. Both PFOA and PFOS inhibited the growth of zebrafish liver cells, and the inhibition rate of PFOS was higher than that of PFOA. Bcl-2 expression levels in the four groups were significantly higher than the control group and Bcl-2 increased significantly in the PFOA-IC80 group. However, the expression levels of Bax in the four treatment groups were higher than the control group. The percentage of cell apoptosis increased significantly with the treatment of PFOA and PFOS (p < 0.05. Cell cycle and cell proliferation were blocked in both the PFOA-IC80 and PFOS-IC80 groups, indicating that PFOA-IC80 and PFOS-IC50 enhanced apoptosis in ZFL cells.

  6. One-step electrochemical synthesis of 6-amino-4-hydroxy-2-napthalene-sulfonic acid functionalized graphene for green energy storage electrode materials

    Science.gov (United States)

    Kuila, Tapas; Khanra, Partha; Kim, Nam Hoon; Kuk Choi, Sung; Yun, Hyung Joong; Lee, Joong Hee

    2013-09-01

    A green approach for the one-step electrochemical synthesis of water dispersible graphene is reported. An alkaline solution of 6-amino-4-hydroxy-2-naphthalene-sulfonic acid (ANS) serves the role of electrolyte as well as surface modifier. High-purity graphite rods are used as electrodes which can be exfoliated under a constant electrical potential (˜20 V) to form ANS functionalized graphene (ANEG). The aqueous dispersion of ANEG obeyed Beer’s law at moderate concentrations, as evidenced from ultraviolet-visible spectroscopy analysis. X-ray diffraction analysis suggests complete exfoliation of graphite into graphene. Fourier transform infrared and x-ray photoelectron spectroscopy not only confirm the functionalization of graphene with ANS, but also suggest the formation of oxygen containing functional groups on the surface of ANEG. Raman spectra analysis indicates the presence of defects in ANEG as compared to pure graphite. Cyclic voltammetry and charge-discharge measurements of ANEG using three electrode systems show a specific capacitance of 115 F g-1 at a current density of 4 A g-1. The ANEG electrode exhibits 93% retention in specific capacitance after 1000 charge-discharge cycles, confirming its utility as a green energy storage electrode material.

  7. Self-assembled platinum nanoparticles on sulfonic acid-grafted graphene as effective electrocatalysts for methanol oxidation in direct methanol fuel cells

    Science.gov (United States)

    Lu, Jinlin; Li, Yanhong; Li, Shengli; Jiang, San Ping

    2016-02-01

    In this article, sulfonic acid-grafted reduced graphene oxide (S-rGO) were synthesized using a one-pot method under mild conditions, and used as Pt catalyst supports to prepare Pt/S-rGO electrocatalysts through a self-assembly route. The structure, morphologies and physicochemical properties of S-rGO were examined in detail by techniques such as atomic force microscope (AFM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The S-rGO nanosheets show excellent solubility and stability in water and the average particle size of Pt nanoparticles supported on S-rGO is ~3.8 nm with symmetrical and uniform distribution. The electrocatalytic properties of Pt/S-rGO were investigated for methanol oxidation reaction (MOR) in direct methanol fuel cells (DMFCs). In comparison to Pt supported on high surface area Vulcan XC-72 carbon (Pt/VC) and Pt/rGO, the Pt/S-rGO electrocatalyst exhibits a much higher electrocatalytic activity, faster reaction kinetics and a better stability. The results indicate that Pt/S-rGO is a promising and effective electrocatalyst for MOR of DMFCs.

  8. A capacitive sensor based on molecularly imprinted polymers and poly(p-aminobenzene sulfonic acid) film for detection of pazufloxacin mesilate

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A novel capacitive sensor for pazufloxacin mesilate (pazufloxacin) determination was developed by electropolymerizing p-aminobenzene sulfonic (p-ABSA) and molecularly imprinted polymers (MIPs), which was synthesized through thermal radical copolymerization of metharylic acid (MAA) and ethyl-ene glycol dimethacrylate (EGDMA) in the presence of pazufloxacin template molecules, on the gold electrode surface. Furthermore, 1-dedecanethiol was used to insulate the modified electrode. Alter-nating current (ac) impedance experiments were carried out with a Model IM6e to obtain the capaci-tance responses. Under the optimum conditions, the sensor showed linear capacitance response to pazufloxacin in the range of 5 ng·mL-1 to 5 μg·mL-1 with a relative standard deviation (RSD) 5.3% (n=7) and a detection limit of 1.8 ng·mL-1. The recoveries for different concentration levels of pazufloxacin samples varied from 94.0% to 102.0%. Electrochemical experiments indicated the capacitive sensor exhibited good sensitivity and selectivity and showed excellent parameters of regeneration and stabil-ity.

  9. A capacitive sensor based on molecularly imprinted polymers and poly(p-aminobenzene sulfonic acid) film for detection of pazufloxacin mesilate

    Institute of Scientific and Technical Information of China (English)

    ZHOU Lu; YE GuangRong; YUAN Ruo; CHAI YaQin; CHEN SuMing

    2007-01-01

    A novel capacitive sensor for pazufloxacin mesilate (pazufloxacin) determination was developed by electropolymerizing p-aminobenzene sulfonic (p-ABSA) and molecularly imprinted polymers (MIPs), which was synthesized through thermal radical copolymerization of metharylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) in the presence of pazufloxacin template molecules, on the gold electrode surface. Furthermore, 1-dedecanethiol was used to insulate the modified electrode. Alternating current (ac) impedance experiments were carried out with a Model IM6e to obtain the capacitance responses. Under the optimum conditions, the sensor showed linear capacitance response to pazufloxacin in the range of 5ng·Ml-1 to 5μg·mL-1 with a relative standard deviation (RSD) 5.3% (n=7) and a detection limit of 1.8 ng·mL-1. The recoveries for different concentration levels of pazufloxacin samples varied from 94.0% to 102.0%. Electrochemical experiments indicated the capacitive sensor exhibited good sensitivity and selectivity and showed excellent parameters of regeneration and stability.

  10. Effect of the intercalated cation-exchanged on the properties of nanocomposites prepared by 2-aminobenzene sulfonic acid with aniline and montmorillonite

    Energy Technology Data Exchange (ETDEWEB)

    Toumi, I. [Laboratoire de Chimie Organique, Macromoleculaire et des Materiaux, Universite de Mascara, Bp 763 Mascara 29000 (Algeria); Benyoucef, A., E-mail: ghani29000@yahoo.fr [Laboratoire de Chimie Organique, Macromoleculaire et des Materiaux, Universite de Mascara, Bp 763 Mascara 29000 (Algeria); Yahiaoui, A. [Laboratoire de Chimie Organique, Macromoleculaire et des Materiaux, Universite de Mascara, Bp 763 Mascara 29000 (Algeria); Quijada, C. [Departamento de Ingenieria Textil y Papelera, Universidad Politecnica de Valencia, Pza Ferrandiz i Carbonel, E-03801 Alcoy, Alicante (Spain); Morallon, E. [Departamento de Quimica Fisica e Instituto Universitario de Materiales, Universidad de Alicante, Apartado 99, E-03080 Alicante (Spain)

    2013-02-25

    Polymer/montmorillonite nanocomposites were prepared. Intercalation of 2-aminobenzene sulfonic acid with aniline monomers into montmorillonite modified by cation was followed by subsequent oxidative polymerization of monomers in the interlayer spacing. The clay was prepared by cation exchange process between sodium cation in (M-Na) and copper cation (M-Cu). XRD analyses show the manifestation of a basal spacing (d-spacing) for M-Cu changes depending on the inorganic cation and the polymer intercalated in the M-Cu structure. TGA analyses reveal that polymer/M-Cu composites is less stable than M-Cu. The conductivity of the composites is found to be 10{sup 3} times higher than that for M-Cu. The microscopic examinations including TEM picture of the nanocomposite demonstrated an entirely different and more compatible morphology. Remarkable differences in the properties of the polymers have also been observed by UV-Vis and FTIR, suggesting that the polymer produced with presence of aniline has a higher degree of branching. The electrochemical behavior of the polymers extracted from the nanocomposites has been studied by cyclic voltammetry which indicates the electroactive effect of nanocomposite gradually increased with aniline in the polymer chain.

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

    Institute of Scientific and Technical Information of China (English)

    纪桂霞; 周步轩; 张欢; 刘弦

    2012-01-01

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

  12. 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.

  13. Design, Synthesis, and Crystal Structures of 6-Alkylidene-2 -Substituted Penicillanic Acid Sulfones as Potent Inhibitors of Acinetobacter baumannii OXA-24 Carbapenemase

    Energy Technology Data Exchange (ETDEWEB)

    Bou, G.; Santillana, E; Sheri, A; Beceiro, A; Sampson, J; Kalp, M; Bethel, C; Distler, A; Drawz, S; et. al.

    2010-01-01

    Class D {beta}-lactamases represent a growing and diverse class of penicillin-inactivating enzymes that are usually resistant to commercial {beta}-lactamase inhibitors. As many such enzymes are found in multi-drug resistant (MDR) Acinetobacter baumannii and Pseudomonas aeruginosa, novel {beta}-lactamase inhibitors are urgently needed. Five unique 6-alkylidene-2{prime}-substituted penicillanic acid sulfones (1-5) were synthesized and tested against OXA-24, a clinically important {beta}-lactamase that inactivates carbapenems and is found in A. baumannii. Based upon the roles Tyr112 and Met223 play in the OXA-24 {beta}-lactamase, we also engineered two variants (Tyr112Ala and Tyr112Ala,Met223Ala) to test the hypothesis that the hydrophobic tunnel formed by these residues influences inhibitor recognition. IC{sub 50} values against OXA-24 and two OXA-24 {beta}-lactamase variants ranged from 10 {+-} 1 (4 vs WT) to 338 {+-} 20 nM (5 vs Tyr112Ala, Met223Ala). Compound 4 possessed the lowest K{sub i} (500 {+-} 80 nM vs WT), and 1 possessed the highest inactivation efficiency (k{sub inact}/K{sub i} = 0.21 {+-} 0.02 {micro}M{sup -1}s{sup -1}). Electrospray ionization mass spectrometry revealed a single covalent adduct, suggesting the formation of an acyl-enzyme intermediate. X-ray structures of OXA-24 complexed to four inhibitors (2.0-2.6 {angstrom}) reveal the formation of stable bicyclic aromatic intermediates with their carbonyl oxygen in the oxyanion hole. These data provide the first structural evidence that 6-alkylidene-2{prime}-substituted penicillin sulfones are effective mechanism-based inactivators of class D {beta}-lactamases. Their unique chemistry makes them developmental candidates. Mechanisms for class D hydrolysis and inhibition are discussed, and a pathway for the evolution of the BlaR1 sensor of Staphylococcus aureus to the class D {beta}-lactamases is proposed.

  14. Benzene metabolites induce apoptosis in lymphocytes.

    Science.gov (United States)

    Martínez-Velázquez, M; Maldonado, V; Ortega, A; Meléndez-Zajgla, J; Albores, A

    2006-08-01

    Benzene is an important environmental pollutant with important health implications. Exposure to this aromatic hydrocarbon is associated with hematotoxicity, and bone marrow carcinogenic effects. It has been shown that benzene induces oxidative stress, cell cycle alterations, and programmed cell death in cultured cells. Hepatic metabolism of benzene is thought to be a prerequisite for its bone marrow toxicity. Nevertheless, there are no reports on the cellular effects of reactive intermediates derived from hepatic metabolism of benzene. Thus, the goal of this project was to determine the cellular alterations of benzene metabolites produced by the cultured hepatic cell line HepG2. Supernatants collected from these cells were applied to a culture of freshly isolated lymphocytes. A higher decrease in cell viability was found in cells exposed to these supernatants than to unmetabolized benzene. This viability decrease was due to apoptosis, as determined by Terminal deoxynucleotidyl Transferase Biotin-dUTP Nick End Labeling (TUNEL) assay and internucleosomal fragmentation of DNA. When supernatants were analyzed by HPLC, we found that not all the hydrocarbon was biotransformed, since a 28 microM concentration (37%) remained. The only metabolite found in the culture medium was muconic acid. The present results show that muconic acid derived from benzene metabolism is able to cooperate with the pollutant for the induction of apoptosis in rat lymphocytes.

  15. Ionic Liquid Catalyst Used in Deep Desulfuration of the Coking Benzene for Producing Sulfurless Benzene

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xia-Ping; WANG Yan-Liang; MENG Fan-Wei; FAN Xing-Ming; QIN Song-Bo

    2008-01-01

    For the widening need of benzene used in organic synthesis, ionic liquid catalyst was prepared to study the process of deep desulfuration in the coking benzene. The result shows that the effect of de-thiophene by the ionic liquid catalyst (N-methyl imidazolium hydrogen sulfate [Hmim][HSO4]) is related to its acid function value.Hammett indicator was used to determine the acid function value H0 of the ionic liquid. It can be concluded that while the acid function value is in the range from -4 to -12, the ionic liquid catalyst can make the concentration certain acid quantity and strength, the ionic liquid catalyst helps to form alkyl thiophene through Friedel-Crafts reaction, which differs from the character of benzene and it is absolutely necessary for the separation and refinement of benzene. But overabundant quantity and higher acid value of [Hmim][HSO4] are more suitable for the side copolymerization of benzene, thiophene and alkene, thereby affecting repeated use of the ionic liquid catalyst([Hmim][HSO4]). In our research, thiophene derivant produced by desulfurization in the coking benzene was used as the polymer to provide the passing channel of the charges. The ionic liquid composition in poor performance after repeated use was made to prepare conductive material (resisting to static electricity) as an "electron-receiving" and "electron-giving" doping agent. The result shows that thiophene derivant after desulfuration in the coking benzene can be used to prepare doping conductive materials.

  16. Biochemical toxicity of benzene.

    Science.gov (United States)

    Rana, S V S; Verma, Yeshvandra

    2005-04-01

    Human exposure to benzene in work environment is a global occupational health problem. After inhalation or absorption, benzene targets organs viz. liver, kidney, lung, heart and brain etc. It is metabolized mainly in the liver by cytochrome P450 multifunctional oxygenase system. Benzene causes haematotoxicity through its phenolic metabolites that act in concert to produce DNA strand breaks, chromosomal damage, sister chromatid exchange, inhibition of topoisomerase II and damage to mitotic spindle. The carcinogenic and myelotoxic effects of benzene are associated with free radical formation either as benzene metabolites or lipid peroxidation products. Benzene oxide and phenol have been considered as proheptons. Liver microsomes play an important role in biotransformation of benzene whereas in kidney, it produces degenerative intracellular changes. Cohort studies made in different countries suggest that benzene induces multiple myeloma in petrochemical workers. Though extensive studies have been performed on its toxicity, endocrinal disruption caused by benzene remains poorly known. Transgenic cytochrome P450 IIE1 mice may help in understanding further toxic manifestations of benzene.

  17. SULFONATION OF A NEW POLYETHERETHERKETONE PREPARED FROM PHENOLPHTHALEIN

    Institute of Scientific and Technical Information of China (English)

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

    1990-01-01

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

  18. Global analysis of myocardial peptides containing cysteines with irreversible sulfinic and sulfonic Acid post-translational modifications

    DEFF Research Database (Denmark)

    Paulech, Jana; Liddy, Kiersten A; Engholm-Keller, Kasper;

    2015-01-01

    Cysteine (Cys) oxidation is a crucial post-translational modification (PTM) associated with redox signaling and oxidative stress. As Cys is highly reactive to oxidants it forms a range of post-translational modifications, some that are biologically reversible (e.g. disulfides, Cys sulfenic acid...

  19. Corrosion inhibition efficiency of linear alkyl benzene derivatives for carbon steel pipelines in 1M HCl

    Directory of Open Access Journals (Sweden)

    A.M. Al-Sabagh

    2011-06-01

    Full Text Available Linear alkyl benzene sulfonic acid (L and three of its ester derivatives (L1, L2, L3 were prepared, followed by quaternization of these esters (L1Q, L2Q, L3Q. The corrosion inhibition effect on carbon steel in 1 M HCl was studied using weight loss and potentiodynamic polarization measurements. The adsorption of the inhibitors on carbon steel surface obeyed the Langmuir’s adsorption isotherm. The associated activation energy of corrosion and other thermodynamic parameters such as enthalpy (ΔH∗, entropy (ΔS∗ of activation, adsorption–desorption equilibrium constant (Kads, standard free energy of adsorption (ΔGoads, heat (ΔHoads, and entropy of adsorption (ΔSoads were calculated to elaborate the corrosion inhibition mechanism.

  20. Benzene from Traffic

    DEFF Research Database (Denmark)

    Palmgren, F.; Berkowicz, R.; Skov, H.;

    The measurements of benzene showed very clear decreasing trends in the air concentrations and the emissions since 1994. At the same time the measurements of CO and NOx also showed a decreasing trend, but not so strong as for benzene. The general decreasing trend is explained by the increasing...... number of petrol vehicles with three way catalysts, 60-70% in 1999. The very steep decreasing trend for benzene at the beginning of the period from 1994 was explained by the combination of more catalyst vehicles and reduced benzene content in Danish petrol. The total amount of aromatics in petrol......, including toluene, increased only weakly. The analyses of air concentrations were confirmed by analyses of petrol sold in Denmark. The concentration of benzene at Jagtvej in Copenhagen is still in 1998 above the expected new EU limit value, 5 µg/m3 as annual average. However, the reduced content of benzene...

  1. 微反应器中十二烷基苯液相SO3磺化过程%Process Performance of Dodecylbenzene Sulfonation with Liquid SO3 in a Microreactor

    Institute of Scientific and Technical Information of China (English)

    主凯; 赵玉潮; 张博宇; 陈光文

    2015-01-01

    Petroleum sulfonates and heavy alkyl benzene sulfonates are important anionic surfactants used in tertiary oil recovery and the active components are alkyl benzene sulfonates. In this work, dodecylbenzene (DDB) sulfonation with liquid SO3 inmicroreactors was used as a model reaction and its reaction performance was studied in a microreactor. The effects of some important parameters on the yield of dodecylbenzene sulfonic acid are investigated, including liquid flow rate, reaction temperature, mass fraction of SO3, length of microchannel, molar ratio of SO3 to dodecylbenzene, reactor types and stirring time. The results showed that the sulfonation of dodecylbenzene is controlled by mass transfer and the initial period of sulfonation can be significantly intensified in the microreactor. With a combination of a microreactor and a tank reactor, the yield of dodecylbenzene sulfonic acid can reach 93.7% under the condition of molar ratio of SO3 to dodecylbenzene 1.1:1.%石油磺酸盐和重烷基苯磺酸盐是三次采油用重要阴离子表面活性剂,其主要成分是烷基苯磺酸盐。本研究以十二烷基苯(DDB)液相SO3磺化为模型反应,研究微反应器内的烷基苯磺酸合成反应过程特性,考察了液体流量、反应温度、磺化剂中 SO3含量、反应通道长度、SO3与十二烷基苯物质的量比、微反应器结构、搅拌时间等参数的影响。结果表明,十二烷基苯磺化过程受传质控制,微反应器对反应初始阶段的强化作用明显,在SO3与十二烷基苯物质的量比为1.1时,采用微反应器与釜式反应器串联模式合成十二烷基苯磺酸,收率高达93.7%,为微反应器生产重烷基苯磺酸的路线提供了重要基础。

  2. Densities and Kinematic Viscosities for the Systems Benzene + Methyl Formate, Benzene + Ethyl Formate, Benzene + Propyl Formate, and Benzene + Butyl Formate

    DEFF Research Database (Denmark)

    Emmerling, Uwe; Rasmussen, Peter

    1998-01-01

    Densities and kinematic viscosities have been measured for the system benzene + methyl formate at 20°C and for the systems benzene + ethyl formate, benzene + propyl formate, and benzene + butyl formate from 20°C to 50°C. The results for the system benzene + methyl formate have been correlated usi...

  3. Fabrication of sulfonated poly(ether ether ketone)-based hybrid proton-conducting membranes containing carboxyl or amino acid-functionalized titania by in situ sol-gel process

    Science.gov (United States)

    Yin, Yongheng; Xu, Tao; He, Guangwei; Jiang, Zhongyi; Wu, Hong

    2015-02-01

    Functionalized titania are used as fillers to modify the sulfonated poly(ether ether ketone) (SPEEK) membrane for improved proton conductivity and methanol barrier property. The functionalized titania sol which contains proton conductive carboxylic acid groups or amino acid groups are derived from a facile chelation method using different functional additives. Then the novel SPEEK/carboxylic acid-functionalized titania (SPEEK/TC) and SPEEK/amino acid-functionalized titania (SPEEK/TNC) hybrid membranes are fabricated via in situ sol-gel method. The anti-swelling property and thermal stability of hybrid membranes are enhanced owing to the formation of electrostatic force between SPEEK and titania nanoparticles. The hybrid membranes exhibit higher proton conductivity than plain SPEEK membrane because more proton transfer sites are provided by the functionalized titania nanoparticles. Particularly, the proton conductivity of SPEEK/TNC membrane with 15% filler content reaches up to 6.24 × 10-2 S cm-1, which is 3.5 times higher than that of the pure SPEEK membrane. For methanol permeability, the SPEEK/TNC membranes possess the lowest values because the acid-base interaction between sulfonic acid groups in SPEEK and amino groups in functionalized titania leads to a more compact membrane structure.

  4. An Efficient Solvent Free Synthesis of 1,8-Dioxo-octahydroxanthene Using p-Toluene Sulfonic Acid

    Institute of Scientific and Technical Information of China (English)

    BAYAT, Mohammad; IMANIEH, Hossien; HOSSIENI, Seyydeh Hajar

    2009-01-01

    A simple and efficient method for the synthesis of 1,8-dioxo-octahydroxanthene by using p-toluenesulfonic acid as a catalyst under solvent free conditions is described, which involves cyclizafion of 2,2-arylmethylenebis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) that was obtained firstly by the reaction of dimedone with aromatic aldehydes in water as solvent and catalyst at room temperature. The experimental procedures in the two steps are very simple and the products are formed in excellent yields.

  5. Irreversible Oxidation of the Active-site Cysteine of Peroxiredoxin to Cysteine Sulfonic Acid for Enhanced Molecular Chaperone Activity*

    OpenAIRE

    2008-01-01

    The thiol (–SH) of the active cysteine residue in peroxiredoxin (Prx) is known to be reversibly hyperoxidized to cysteine sulfinic acid (–SO2H), which can be reduced back to thiol by sulfiredoxin/sestrin. However, hyperoxidized Prx of an irreversible nature has not been reported yet. Using an antibody developed against the sulfonylated (–SO3H) yeast Prx (Tsa1p) active-site peptide (AFTFVCPTEI), we observed an increase in the immunoblot intensity in proportion to the ...

  6. Development of Hollow-Fiber Liquid-Phase Microextraction Method for Determination of Urinary trans,trans-Muconic Acid as a Biomarker of Benzene Exposure

    Science.gov (United States)

    Ghamari, Farhad; Bahrami, Abdulrahman; Yamini, Yadollah; Shahna, Farshid Ghorbani; Moghimbeigi, Abbas

    2016-01-01

    For the first time, hollow-fiber liquid-phase microextraction combined with high-performance liquid chromatography–ultraviolet was used to extract trans,trans-muconic acid, in urine samples of workers who had been exposed to benzene. The parameters affecting the metabolite extraction were optimized as follows: the volume of sample solution was 11 mL with pH 2, liquid membrane containing dihexyl ether as the supporter, 15% (w/v) of trioctylphosphine oxide as the carrier, the time of extraction was 120 minutes, and stirring rate was 500 rpm. Organic phase impregnated in the pores of a hollow fiber was extracted into 24 µL solution of 0.05 mol L−1 Na2CO3 located inside the lumen of the fiber. Under optimized conditions, a high enrichment factor of 153–182 folds, relative recovery of 83%–92%, and detection limit of 0.001 µg mL−1 were obtained. The method was successfully applied to the analysis of ttMA in real urine samples. PMID:27660405

  7. Magnetic graphene - polystyrene sulfonic acid nano composite: A dispersive cation exchange sorbent for the enrichment of aminoalcohols and ethanolamines from environmental aqueous samples.

    Science.gov (United States)

    Chinthakindi, Sridhar; Purohit, Ajay; Singh, Varoon; Tak, Vijay; Dubey, D K; Pardasani, Deepak

    2015-12-04

    Present study aimed at graphene surface modification to achieve selective analyte binding in dispersive solid phase extraction. Magnetic graphene - polystyrene sulfonic acid (MG-PSS) cation exchange nano-composite was prepared by non-covalent wrapping method. Composite was characterized by FT-IR and zeta potential. Material exhibited good dispersion in water and high exchange capacity of 1.97±0.16mMg(-1). Prepared nano-sorbent was then exploited for the cation exchange extraction and gas chromatography mass spectrometric analysis of Chemical Weapons Convention relevant aminoalcohols and ethanolamines from aqueous samples. Extraction parameters such as sorbent amount, extraction time, desorption conditions and sample pH were optimized and effect of common matrix interferences such as polyethylene glycol and metal salts was also studied. Three milligram of sorbent per mL of sample with 20min of extraction time at room temperature afforded 70-81% recoveries of the selected analytes spiked at concentration level of 1μgmL(-1). Method showed good linearity in the studied range with r(2)≥0.993. The limits of detection and limits of quantification ranged from 23 to 54ngmL(-1) and 72 to 147ngmL(-1), respectively. The relative standard deviation for intra- and inter-day precision ranged from 4.6 to 10.2% and 7.4 to 14.8% respectively. Applicability of the method to different environmental samples as well as the proficiency tests conducted by the Organization for the Prohibition of Chemical Weapons (OPCW) was also ascertained.

  8. Detecting a quasi-stable imine species on the reaction pathway of SHV-1 β-lactamase and 6β-(hydroxymethyl)penicillanic acid sulfone.

    Science.gov (United States)

    Che, Tao; Rodkey, Elizabeth A; Bethel, Christopher R; Shanmugam, Sivaprakash; Ding, Zhe; Pusztai-Carey, Marianne; Nottingham, Michael; Chai, Weirui; Buynak, John D; Bonomo, Robert A; van den Akker, Focco; Carey, Paul R

    2015-01-27

    For the class A β-lactamase SHV-1, the kinetic and mechanistic properties of the clinically used inhibitor sulbactam are compared with the sulbactam analog substituted in its 6β position by a CH2OH group (6β-(hydroxymethyl)penicillanic acid). The 6β substitution improves both in vitro and microbiological inhibitory properties of sulbactam. Base hydrolysis of both compounds was studied by Raman and NMR spectroscopies and showed that lactam ring opening is followed by fragmentation of the dioxothiazolidine ring leading to formation of the iminium ion within 3 min. The iminium ion slowly loses a proton and converts to cis-enamine (which is a β-aminoacrylate) in 1 h for sulbactam and in 4 h for 6β-(hydroxymethyl) sulbactam. Rapid mix-rapid freeze Raman spectroscopy was used to follow the reactions between the two sulfones and SHV-1. Within 23 ms, a 10-fold excess of sulbactam was entirely hydrolyzed to give a cis-enamine product. In contrast, the 6β-(hydroxymethyl) sulbactam formed longer-lived acyl-enzyme intermediates that are a mixture of imine and enamines. Single crystal Raman studies, soaking in and washing out unreacted substrates, revealed stable populations of imine and trans-enamine acyl enzymes. The corresponding X-ray crystallographic data are consonant with the Raman data and also reveal the role played by the 6β-hydroxymethyl group in retarding hydrolysis of the acyl enzymes. The 6β-hydroxymethyl group sterically hinders approach of the water molecule as well as restraining the side chain of E166 that facilitates hydrolysis.

  9. Toxicity of perfluorooctane sulfonate and perfluorooctanoic acid to Escherichia coli: Membrane disruption, oxidative stress, and DNA damage induced cell inactivation and/or death.

    Science.gov (United States)

    Liu, Gesheng; Zhang, Shuai; Yang, Kun; Zhu, Lizhong; Lin, Daohui

    2016-07-01

    Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are two widely used polyfluorinated compounds (PFCs) and are persistent in the environment. This study for the first time systematically investigated their toxicities and the underlying mechanisms to Escherichia coli. Much higher toxicity was observed for PFOA than PFOS, with the 3 h half growth inhibition concentrations (IC50) determined to be 10.6 ± 1.0 and 374 ± 3 mg L(-1), respectively, while the bacterial accumulation of PFOS was much greater than that of PFOA. The PFC exposures disrupted cell membranes as evidenced by the dose-dependent variations of cell structures (by transmission electron microscopy observations), surface properties (electronegativity, hydrophobicity, and membrane fluidity), and membrane compositions (by gas chromatogram and Fourier transform infrared spectroscopy analyses). The increases in the contents of intracellular reactive oxygen species (ROS) and malondialdehyde and the activity of superoxide dismutase indicated the increment of oxidative stress induced by the PFCs in the bacterial cells. The fact that the cell growth inhibition was mitigated by the addition of ROS scavenger (N-acetyl cysteine) further evidenced the important role of oxidative damage in the toxicities of PFOS and PFOA. Eighteen genes involved in cell division, membrane instability, oxidative stress, and DNA damage of the exposed cells were up or down expressed, indicating the DNA damage by the PFCs. The toxicities of PFOS and PFOA to E. coli were therefore ascribed to the membrane disruption, oxidative stress, and DNA damage induced cell inactivation and/or death. The difference in the bactericidal effect between PFOS and PFOA was supposed to be related to their different dominating toxicity mechanisms, i.e., membrane disruption and oxidative damage, respectively. The outcomes will shed new light on the assessment of ecological effects of PFCs.

  10. Crystal Structures of KPC-2[beta]-Lactamase in Complex with 3-Nitrophenyl Boronic Acid and the Penam Sulfone PSR-3-226

    Energy Technology Data Exchange (ETDEWEB)

    Ke, Wei; Bethel, Christopher R.; Papp-Wallace, Krisztina M.; Pagadala, Sundar Ram Reddy; Nottingham, Micheal; Fernandez, Daniel; Buynak, John D.; Bonomo, Robert A.; van den Akker, Focco (Case Western); (Stokes); (SMU)

    2012-08-01

    Class A carbapenemases are a major threat to the potency of carbapenem antibiotics. A widespread carbapenemase, KPC-2, is not easily inhibited by {beta}-lactamase inhibitors (i.e., clavulanic acid, sulbactam, and tazobactam). To explore different mechanisms of inhibition of KPC-2, we determined the crystal structures of KPC-2 with two {beta}-lactamase inhibitors that follow different inactivation pathways and kinetics. The first complex is that of a small boronic acid compound, 3-nitrophenyl boronic acid (3-NPBA), bound to KPC-2 with 1.62-{angstrom} resolution. 3-NPBA demonstrated a Km value of 1.0 {+-} 0.1 {micro}M (mean {+-} standard error) for KPC-2 and blocks the active site by making a reversible covalent interaction with the catalytic S70 residue. The two boron hydroxyl atoms of 3-NPBA are positioned in the oxyanion hole and the deacylation water pocket, respectively. In addition, the aromatic ring of 3-NPBA provides an edge-to-face interaction with W105 in the active site. The structure of KPC-2 with the penam sulfone PSR-3-226 was determined at 1.26-{angstrom} resolution. PSR-3-226 displayed a K{sub m} value of 3.8 {+-} 0.4 {micro}M for KPC-2, and the inactivation rate constant (kinact) was 0.034 {+-} 0.003 s{sup -1}. When covalently bound to S70, PSR-3-226 forms a trans-enamine intermediate in the KPC-2 active site. The predominant active site interactions are generated via the carbonyl oxygen, which resides in the oxyanion hole, and the carboxyl moiety of PSR-3-226, which interacts with N132, N170, and E166. 3-NPBA and PSR-3-226 are the first {beta}-lactamase inhibitors to be trapped as an acyl-enzyme complex with KPC-2. The structural and inhibitory insights gained here could aid in the design of potent KPC-2 inhibitors.

  11. Properties of a novel acid dye 1-amino-4-[(6-nitro-2-benzothiazolyl)amino]-9,10-anthraquinone-2-sulfonic acid with anti-UV capability

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A novel acid dye acid was synthesized by the condensation reaction between bromamine acid and 2-amino-6-nitrobenzothiazole and its anti-UV protection properties were evaluated.The results showed that silk dyed with this dye had very good ultraviolet radiation protection capability and excellent dyeing performance.The UV-absorption mechanism of this dye was also discussed.

  12. Preparation of biodiesel catalyzed by sulfonic acid-functionalized ionic liquids%磺酸型离子液体催化制备生物柴油的研究

    Institute of Scientific and Technical Information of China (English)

    郭永刚; 黄宝华; 史娜; 霍延平; 张焜

    2013-01-01

    制备了具有咪唑、吗啡啉、吡咯烷酮和吡啶等氮杂环的8种硫酸氢盐离子液体,并考察了这些离子液体应用于大豆油和甲醇的酯交换制备生物柴油的催化活性.其中4种离子液体为1-甲基眯唑硫酸氢盐、吗啡啉硫酸氢盐、2-吡咯烷酮硫酸氢盐、吡啶硫酸氢盐,其余为基于该4种氮杂环引入丙烷磺酸基的磺酸型离子液体.离子液体的酸性测定结果表明,氮杂环相同时,引入磺酸基的离子液体酸性得以增强,催化活性均高于非磺酸型离子液体.磺酸型离子液体的催化活性可与浓硫酸相比拟,反应结束后均可与生物柴油产物自动分层.以活性较佳的1-(3-磺丙基)-2-吡咯烷酮硫酸氢盐和4-(3-磺丙基)吗啡啉硫酸氢盐作催化剂时,n(甲醇)∶n(大豆油)∶n(IL) =12∶1∶0.114,油浴120℃下反应6h,生物柴油收率分别可达95.0%和94.6%.磺酸型吗啡啉离子液体重复使用5次后,催化活性没有明显下降.%Eight kinds of hydrosulfate ionic liquid based on imidazolium,morpholinium,pyrrolidonium and pyridinium cations were synthesized,and the catalytic activities in transesterification of soybean oil with methanol were investigated.Four of them are 1-methylimidazolium hydrogen sulfate ([Hmim] HSO4),morpholinium hydrogen sulfate ([Hnhm]HSO4),2-pyrrolidonium hydrogensulfate ([Hnhp] HSO4)and pyridinium hydrogensulfate ([Hpy] HSO4),the others are sulfonic acid-functionalized ionic liquids.The acidities and catalytic activities of sulfonic acid-functionalized ionic liquids were higher than non sulfonic acid-functionalized ionic liquids.The catalytic activities of sulfonic acid-functionalized ionic liquids can be comparable with concentrated sulphuric acid,and these ionic liquids were phase-separated with biodiesel after the reaction.While 1-(3-sulfonic acid) propyl-2-pyrrolidonium and 4-(3-sulfonic acid)propylmorpholinium as catalysts,under the optimized conditions of n(methanol) ∶n(soybean oil

  13. Preparation of Sulfuric Acid Sulfonated Modified Starch and Testing Study of Its Scale Inhibition Properties%硫酸磺化改性淀粉制备及阻垢性能试验研究

    Institute of Scientific and Technical Information of China (English)

    刘玉玲; 高升; 刘利

    2011-01-01

    为了减轻和避免目前阻垢剂排放对环境造成的污染,本实验利用浓硫酸氧化淀粉制备改性淀粉,其颜色为棕红色;在不同浓度、温度、Ca2+浓度、pH值下,对硫酸磺化改性淀粉的阻垢性能进行测试.实验结果表明,硫酸磺化改性淀粉高效阻垢的最佳浓度为0.61 mg/L,最佳温度为80℃,对应的阻垢效率为84.7%.其阻垢效率随着Ca2+浓度及pH值的增加而减小,因此Ca2+浓度、pH值是影响阻垢剂阻垢效率的重要因素.对硫酸磺化改性淀粉与其它氧化改性淀粉的阻垢性能进行的比较实验结果表明,硫酸磺化改性淀粉的阻垢性能优于其它改性淀粉.%In order to mitigate and avoid current scale inhibitor pollution emissions on the environment, in this lab, the concentrated sulfuric acid oxidized starch is used to prepare the modified starch, whose color is brown-red.Sulfuric acid sulfonated modified starch is tested in case of different concentrations, temperatures, Ca2+ concentrations, pH values.It has been found that the best concentration of efficient scale of sulfuric acid sulfocated modified starch is 0.61 mg/L, and that the best temperature is 80 ℃, and that under this best concentration and temperature the corresponding inhibition rate is 84.7 %.The inhibition rate of sulfuric acid sulfonated modified starch decreases with an increase in Ca2+ concentration and pH value, thus, indicating that Ca2+ concentration and pH are the important factors that can affect the inhibition rate of scale inhibitor.Finally, the comparison is made of scale performance between sulfuric acid sulfonated modified starch and other oxidized modified starch, with the results showing that the scale inhibition of sulfuric acid sulfonated modified starch is superior to other oxidized modified starch.

  14. Synthesis of Poly(N-methylol Methacrylamide/Vinyl Sulfonic Acid) Hydrogels for Heavy Metal Ion Removal

    Energy Technology Data Exchange (ETDEWEB)

    Arzu Yakar [Afyon Kocatepe University, Afyonkarahisar (Turkey)

    2014-09-15

    In this study, poly(N-methylol methacrylamide) (NMMAAm) and poly(N-methylol methacrylamide/vinyl sulphonic acid) (NMMAAm-VSA) hydrogels were synthesized by 60Co-γ ray irradiation at an ambient temperature. The graphs belonging to the gelation percent- percent-dose and swelling curves were drawn by using data which were obtained from water and different pH solutions. Characterization of hydrogels was performed by FTIR and DSC-TGA analysis. Heavy metal ion (Ni{sub 2}+, Co{sub 2}+) removal capacities of hydrogels were investigated in aqueous solutions, which had different concentrations (100-1500 mg/L). In metal ion removal studies, pH value of aqueous medium was kept constant at 5.0. Maximum metal ion removal values were obtained for NMMAAm-VSA (1:3 mole ratio) hydrogels. Metal ion removal capacities of NMMAAm- VSA (1:3 mole ratio) hydrogels were found as 82 mg/g and 98 mg/g for Ni{sub 2}+ and Co{sub 2}+ ions, respectively.

  15. Investigation of mitigating effect of colon-specific prodrugs of boswellic acid on 2,4,6-trinitrobenzene sulfonic acid-induced colitis in Wistar rats: Design, kinetics and biological evaluation

    Science.gov (United States)

    Sarkate, Ajinkya; Dhaneshwar, Suneela S

    2017-01-01

    AIM To develop a colon-targeting bioreversible delivery system for β-boswellic acid (BBA) and explore utility of its prodrugs in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats. METHODS Synthesis of 4 co-drugs of BBA with essential amino acids was achieved by CDI coupling, followed by their spectral characterization. In vitro kinetics were studied by HPLC in aqueous buffers, homogenates of gastrointestinal tract and fecal matter. In vivo kinetic studies were performed in Wistar rat plasma, urine and feces. The prodrugs were screened in TNBS-induced colitis modeled Wistar rats. Statistical significance was assumed at P rat fecal matter and homogenates of colon. In vivo studies of BBA with L-tryptophan (BT) authenticated colon-specific release of BBA. But, surprisingly substantial concentration of BBA was seen to reach the systemic circulation due to probable absorption through colonic mucosa. Site-specifically enhanced bioavailability of BBA could be achieved in colon, which resulted in demonstration of significant mitigating effect on TNBS-induced colitis in rats without inducing any adverse effects on stomach, liver and pancreas. Prodrug of BT was found to be 1.7% (P < 0.001) superior than sulfasalazine in reducing the inflammation to colon among all prodrugs tested. CONCLUSION The outcome of this study strongly suggests that these prodrugs might have dual applicability to inflammatory bowel disease and chronotherapy of rheumatoid arthritis. PMID:28275295

  16. 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

  17. 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.

  18. Selective removal of Cr(VI) from aqueous solution by polypyrrole/2,5-diaminobenzene sulfonic acid composite.

    Science.gov (United States)

    Kera, Nazia H; Bhaumik, Madhumita; Ballav, Niladri; Pillay, Kriveshini; Ray, Suprakas Sinha; Maity, Arjun

    2016-08-15

    A polypyrrole/2,5-diaminobenzenesulfonic acid (PPy/DABSA) composite, synthesised by the in situ oxidative polymerization of pyrrole in the presence of DABSA, was studied as an adsorbent for the removal of Cr(VI) from aqueous solution. The structure and morphology of the composite were investigated by ATR-FTIR, FE-SEM, EDX, TGA, XRD and XPS studies. The adsorption of Cr(VI) by PPy/DABSA composite was highly pH dependent and optimum removal was achieved at pH 2. Adsorption of Cr(VI) was confirmed by EDX and XPS studies. The isotherm data fitted the linear Langmuir model well, with a maximum adsorption capacity of 303mg/g at 25°C. Thermodynamic parameters (ΔG°, ΔH° and ΔS°) were calculated using isotherm data and confirmed that the adsorption process was spontaneous and endothermic. Adsorption kinetics was best described by the pseudo-second-order model. The activation energy of the adsorption process suggested that Cr(VI) was chemisorbed by PPy/DABSA composite. PPy/DABSA composite could be used for three consecutive adsorption-desorption cycles without loss of its original adsorption capacity. Highly selective removal of Cr(VI) was observed even when co-existing ions such as Cu(2+), Zn(2+), Ni(2+), Cl(-), SO4(2)(-) and NO3(-) were present in the solution. In summary, the potential of PPy/DABSA composite for remediating industrial wastewater contaminated by Cr(VI) has been demonstrated.

  19. Effects of mimic of manganese superoxide dismutase on 2,4,6-trinitrobenzene sulfonic acid-induced colitis in rats.

    Science.gov (United States)

    Wang, Yan-Hong; Dong, Jiao; Zhang, Jian-Xin; Zhai, Jing; Ge, Bin

    2016-09-01

    The mimic of manganese superoxide dismutase (MnSODm) has been synthesized and reported to have anti-inflammatory properties. However, whether MnSODm has anti-inflammatory effects on colitis and any underlying mechanisms are poorly understood. This study was to investigate therapeutic effects and mechanism of MnSODm on 2,4,6-trinitrobenzenesulfonic acid (TNBS) induced colitis model in rats. Rats were intragastrically administered MnSODm (10, 20, and 40 mg/kg) per day for 7 days after colitis was induced by TNBS. After treated with MnSODm, the colonic macroscopic and microscopic damage scores and colonic weight/length ratios were significantly decreased compared with colitis model group. Myeloperoxidase (MPO) activity, malonyldialdehyde (MDA), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, and IL-8 levels in colon tissues were also significantly decreased in MnSODm treatment groups. However, superoxide dismutase (SOD) activity significantly increased and phosphorylated inhibitory kappa B-alpha (IκBα), inhibitor kappa B kinase (IKKα/β), and nuclear factor-kappa Bp65 (NF-κBp65) as well as Toll-like receptor 4 (TLR4) and myeloid differentiation actor 88 (MyD88) in the colonic mucosa were significantly inhibited by MnSODm treatment. Thus, MnSODm was protective against colitis via antioxidant activity and by inhibiting inflammatory mediators by down-regulating TLR4/MyD88/NF-κB signaling pathways. These data suggest a potential therapeutic effect of MnSODm in colitis.

  20. [Benzene in soft drinks: a study in Florence (Italy)].

    Science.gov (United States)

    Bonaccorsi, Guglielmo; Perico, Andrea; Colzi, Alessio; Bavazzano, Paolo; Di Giusto, Maurizio; Lamberti, Ilaria; Martino, Gianrocco; Puggelli, Francesco; Lorini, Chiara

    2012-01-01

    The aim of this study was to determine the amount of benzene present in soft drinks sold in Florence (Italy). We analyzed 28 different types of soft drinks, by measuring concentrations of benzoic acid, sorbic acid, ascorbic acid (using high performance liquid chromatography with UV detection) and benzene (using gas chromatography and mass spectrometry). Data was analysed by using SPSS 18.0.Traces of benzene were detected in all analyzed beverages, with a mean concentration of 0.45 µg/L (range: 0.15-2.36 µg/L). Statistically significant differences in mean benzene concentrations were found between beverages according to the type of additive indicated on the drink label, with higher concentrations found in beverages containing both ascorbic acid and sodium benzoate. Two citrus fruit-based drinks were found to have benzene levels above the European limit for benzene in drinking water of 1 µg /L. Sodium benzoate and ascorbic acid were also detected in the two drinks.In conclusion, not all soft drink producers have taken steps to eliminate benzoic acid from their soft drinks and thereby reduce the risk of formation of benzene, as recommended by the European Commission. Furthermore, the presence of benzene in trace amounts in all beverages suggests that migration of constituents of plastic packaging materials or air-borne contamination may be occurring.

  1. 十二烷基苯磺酸钠-异辛烷-正辛醇反胶束萃取苦参生物碱的研究%Extraction of Alkaloids in Sophora Flavescens Ait by Reverse Micelle of Sodium Dodecyl Benzene Sulfonate/Isooctane/n-Octanol

    Institute of Scientific and Technical Information of China (English)

    刘小琴; 范华均; 佘旭辉; 张来凤; 王李平

    2012-01-01

    利用阴离子表面活性剂十二烷基苯磺酸钠(SDBS)与溶剂异辛烷和助溶剂正辛醇形成反胶束体系,用于苦参生物碱的萃取分离.研究了pH值、表面活性剂浓度、增溶水量W0、盐种类及浓度等因素对萃取的影响.结果表明:SDBS-异辛烷-正辛醇反胶束体系对苦参生物碱具有良好的选择性和较高萃取率,在pH 5.0,增溶水量W0 25,0.05 mol/L SDBS,0.05 mol/L KCl,室温,萃取时间5 min,反萃取时间20 min的最佳萃取条件下,氧化苦参碱、氧化槐果碱、槐定碱、苦参碱、槐果碱5种生物碱及总生物碱的萃取率和RSD分别在74.1%~87.2%和0.63%~3.0%之间.本方法选择性高,操作简便.%A method of reverse micelle extraction of alkaloids in Sophora Flavescens Ait has been developed using the reverse micelle system of sodium dodecyl benzene sulfonate(SDBS)/isooctane/ n-octanol. The experimental conditions such as pH, water content Wo, extraction time and temperature, the concentration of surfactant and salts were optimized. With the help of high performance liquid chromatography, the results showed that the reverse micelle formed by SDBS, isooctane and n-octanol can more effectively extract alkaloids than others. The optimum extraction conditions were as follows: pH 5. 0, 25 of water content Wo, 0. 05 mol/L of SDBS concentration, 0. 05 mol/L of KC1 concentration, 5 min of forward-extraction time and 20 min of backward-extraction time at room temperature. The method has been applied to separate and purify alkaloids from the extract by water with pressurized microwave-assisted extraction. Under the optimum conditions, the extraction yields of oxymatrine, n-oxysophocarpine, sophoridine, matrine, sophocarpine and total alkaloids in Sophora Flavescens Ait were between 74. 1% and 87. 2%, RSDs of their reproducibility were from 0. 6% to 3. 0%. The method is higher selectivity, and easy to operate.

  2. Effect of intensity of ultraviolet light on degradation of sodium dodecyl benzene sulfonate by TiO2-bentonite%紫外光光强对TiO2-膨润土降解十二烷基苯磺酸钠的影响

    Institute of Scientific and Technical Information of China (English)

    温淑瑶; 马敏立; 陈素云; 马占青

    2011-01-01

    在室温、电磁搅拌和6W紫外灯(距静止液面距离分别为6.5 cm、18.5 cm、30.5 cm和42.5 cm)的不同光强(在静止液面处的光强分别为700~750 μW/cm2、300~310μW/cm2、200~210 μW/cm2和110~120μW/cm2),及太阳光的不同紫外光强度照射条件下,质量分数为0.5‰的纳米TiO2-膨润土复合光催化剂对初始质量浓度为20 mg/L的十二烷基苯磺酸钠(SDBS)溶液中SDBS的降解反应表明:光强对SDBS降解的影响较大,光强越强SDBS的降解率越高、溶液的COD值降低率越大;不同光强下,TiO2-膨润土对SDBS降解反应为一级反应,符合Langmuir-Hinshelwood方程;随着光强的增大,TiO2-膨润土对SDBS降解的光催化反应速率常数增大.%Different intensities of ultraviolet light (700~750 (μW/cm2 ,300~310μ/W/cm2,200~210μW/cm2 and 110-120 μW/cm2)resulted from different distances(6.5 cm, 18.5 cm,30.5 cm and 42.5 cm ) between 6 W ultraviolet light and still solution surface respectively.Original concentration of sodium dodecyl benzene sulfonate (SDBS) was 20mg/L.Under the same condition (temperature, ultraviolet light shining period, electromagnetic mixing, Ph 6 ) and different intensities of light, the results of degradation reaction of SDBS by 0.5 TiO2-bentonite show that the effect of intensity of light on degradation is obvious.The higher the intensity of ultraviolet light, the more the SDBS was degradated.The higher the intensity of ultraviolet light, the more the chemical oxide demand of solution decreased.The degradation reaction was first-order reaction.Its law of dynamics accorded with Langmuir-Hinshelwood equation.The higher the intensity of ultraviolet light, the bigger the speed coefficient of photocatalytic reaction between SDBS and TiO2-bentonite.

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

    Science.gov (United States)

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

    2016-12-01

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

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

    Science.gov (United States)

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

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

    Science.gov (United States)

    Ward, T E; Larson, R J

    1989-02-01

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

  6. Benzene toxicity of the occurrence of benzene in the ambient air of the Houston area

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Y.C.

    1980-01-01

    This study was conducted by either literature review or actual field survey. Results are summarized as follows: (1) long-term occupational exposure of workers to benzene vapor at levels of 3 to 7 ppM, 2 to 3 ppM and 1.6 ppM may result in a decreased level of leucocyte alkaline phosphates, an increased incidence of chromosome aberrations and an increased level of ALA in erythrocytes, respectively; (2) benzene is capable of causing fetotoxic effects in animals at levels as low as 10 ppM by volume; (3) exposure of animals to or less than 1 ppM benzene vapor may result in leucopenia, an inverse ratio of muscle antagonist chronaxy and a decreased level of ascorbic acid in fetus's and mother's liver as well as whole embryo; (4) benzene is causally associated with the increased incidence of pancytopenia, including unicytopenia, bicytopenia and aplastic anemia, and chromosome aberrations in occupational exposure population, and at best benzene must also be considered as a leukemogen; (5) since it can be emitted into the atmosphere from both man-made and natural sources, benzene in some concentrations is presented everywhere in the various compartments of the environment; (6) the findings of the emission of benzene from certain natural sources indicate that reducing benzene to a zero-level of exposure is theoretically impossible; (7) the annual average of benzene concentration detected in the Houston ambient air is 2.50 ppB, which is about 2.4 times higher than the nation-wide annual average exposure level and may have some health implications to the general public; and (8) in the Houston area, stationary sources are more important than mobile sources in contributing to benzene in the ambient air.

  7. Sijunzi Decoction attenuates 2, 4, 6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats and ameliorates TNBS-induced claudin-2 damage via NF-κB pathway in Caco2 cells

    OpenAIRE

    Lu, Yue; Lin, HanJie; Zhang, Jinwei; Wei, JianAn; Jing SUN; Han, Ling

    2017-01-01

    Background SijunziDecoction (SJZD) is a traditional Chinese medicine prescription used to treat the diseases of gastrointestinal tract since ancient times. The objective of this study was to investigate the protective effects of SJZD on TNBS-induced colitis in rats and TNBS-damaged Caco2 cells. Methods The rat colitis model was induced by 2, 4, 6-trinitrobenzene sulfonic acid (TNBS). SJZD (2.8 5.6, 11.2 g/kg) or salazosulfapyridine (SASP) (0.4 g/kg) was administrated orally in rats for 7 days...

  8. Hydroxylation of benzene with hydrogen peroxide under phase-transfer conditions

    Energy Technology Data Exchange (ETDEWEB)

    Karakhanov, E.A.; Narin, S.Yu.; Filippova, T.Yu.; Dedov, A.G.

    1987-09-01

    The authors developed a method for the selective hydroxylation of benzene to phenol with hydrogen peroxide in a two-phase water-benzene system in the presence of ions of transition metals and phase-transfer catalysts. As phase-transfer catalysts they used cetyltrimethylammonium bromide, tetrabutyl-ammonium bromide, tetrabutylammonium chloride, tetrabutylammonium iodide, benzyltriethylammonium chloride, dibenzo-18-crown-6, benzo-15-crown-5, N-cetylpyridinium bromide, potassium didodecylsebacinate ..cap alpha..-sulfonate, and polyethylene glycols of various molecular weight. They were able to find the optimal conditions for the selective hydroxylation of benzene with hydrogen peroxide under phase-transfer catalysis conditions.

  9. AA/AMPS水凝胶的交联聚合反应动力学及其机理%Crosslink Polymerization Kinetics and Mechanism of Hydrogels Composed of Acrylic Acid and 2-Acrylamido-2-methylpropane Sulfonic Acid

    Institute of Scientific and Technical Information of China (English)

    廖列文; 岳航勃; 崔英德

    2011-01-01

    Crosslink polymerization kinetics of poly(acrylic acid-co-2-acrylamido-2-methylpropane sulfonic acid),AA/AMPS hydrogels, was investigated by using dilatometry in the presence of sodium persulfate as initiator and N,N'-methylene bis(acrylamide) as crosslinker. It was found that the reaction for the cross/ink polymerization of AA/AMPS hydrogels had orders of 0.58, 1.14, and 0.86 with respect to the initiator, AMPS, and AA, respectively.From the Arrhenius plots, the activation energy of the crossLink polymerization was found to be about 140 and 89 kJ·mol-1 in the presence and absence of the crosslinker, respectively, in the temperature range from 45 to 65 ℃. It was noted that the crosslinker had effects on the reaction order of the initiator and the activation energy due to the formation of cross-linked networks, which was verified by Fourier transfer infrared (FTLR) spectrum. To further confirm the influences of the cross-linked network structure on kinetic parameters of the crosslink polymerization, a mechanism was proposed, which highlights the different termination routes between free radical polymerization and crosslink polymerization. These results suggest that dilatometry provides a convenient tool for crosslink polymerization study, and confirm that the cross-linked networks are formed in the crosslink polymerization.

  10. 磺酸基羟丙基瓜尔胶的制备和性能%PREPARATION AND PROPERTIES OF SULFONIC ACID HYDROXYPROPYL GUAR GUM

    Institute of Scientific and Technical Information of China (English)

    曹军胜; 龙柱; 朱莹

    2011-01-01

    以3-氯-2-羟基丙磺酸钠,瓜尔胶原粉为原料,在碱性催化剂作用下采用湿法合成了磺酸基羟丙基瓜尔胶.讨论了外加盐、酸度、取代度和不同浓度的瓜尔胶水溶液对磺酸基羟丙基瓜尔胶流变曲线的影响,并通过红外光谱,扫描电镜,核磁图谱,XRD等进行了分析.结果发现,随着外加盐浓度的增大,表观黏度逐渐减小,表现出明显的聚电解质的通性,AlCl3> MgCl2> NaC1.随着酸度的增大,表观黏度在pH值约为7时达到最大,随后减小趋势趋于平缓,表明对酸的敏感程度远远大于对碱的敏感程度;随着取代度的增大,水不溶物含量和表观黏度逐渐减小,在取代度超过0.3的时候,减小趋势趋于平缓;随着剪切速率的增大,表观黏度逐渐减小.%Sulfonic acid hydroxypropyl guar gum (SHGG) was prepared in laboratory by a wet process based on the reaction of guar gum and sodium 3-chloro-2-hydroxy propanesulfonate with an alkali catalyst. The effects of SHGG aqueous solution, including electrolyte added, acidity, substitution degree and concentration on the rheology properties of SHGG were investigated. The structure of the guar gum product was characterized by IR, SEM, NMR, XRD, and DSC. The results showed that SHGG aqueous solution had the behaviors of typical polymerizing-electrolyte. Additionally, the effect of the high metal ion was bigger than that of low metal ion: AlCl3>MgCl2>NaCl. The viscosity of SHGG aqueous solution decreased with increasing the concentration of electrolyte. With the acidity increased, the apparent viscosity reached the maximum about pH 7. 0, and then decreased slightly, showing that the sensibility of SHGG aqueous solution to acid is more pronounced than that to alkali. The insoluble residue and the apparent viscosity reduced following the substitution degree increased. When the substitution degree was greater than 0. 3, the tendency became gentle. The apparent viscosity decreased with

  11. A rapid method for the determination of perfluoroalkyl substances including structural isomers of perfluorooctane sulfonic acid in human serum using 96-well plates and column-switching ultra-high performance liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Salihovic, Samira; Kärrman, Anna; Lindström, Gunilla; Lind, P Monica; Lind, Lars; van Bavel, Bert

    2013-08-30

    To facilitate high-throughput analysis suitable for large epidemiological studies we developed an automated column-switching ultra-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for determination of perfluorocarboxylic acids (PFCAs; C5, C6, C7, C8, C9, C10, C11, C12, and C13), perfluoroalkyl sulfonic acids (PFSAs; C4, C6, C8, and C10), perfluorooctane sulfonamide (PFOSA), and five groups of structural perfluorooctane sulfonic acid (PFOS) isomers in human serum or plasma. The analytical procedure involves rapid protein precipitation using 96-well plates followed by an automated sample clean-up using an on-line trap column removing many potentially interfering sample components while through the mobile phase gradient the target analytes are eluted onto the analytical column for further separation and subsequent mass detection. The method was linear (R(2)method detection limits ranging between 0.01 and 0.17ngmL(-1) depending on the analyte. The developed method was precise, with repeatability (n=7) and reproducibility (n=103) coefficients of variation between 2% and 20% for most compounds including PFOS (2% and 8%) and its structural isomers (2-6% and 4-8%). The method was in conformity with a standard reference material. The column-switching HPLC-MS/MS method has been successfully applied for the determination of perfluoroalkyl substances including structural PFOS isomers in human plasma from an epidemiological study.

  12. Influence of Shenqing Recipe on Morphology and Quantity of Colonic Interstitial Cells of Cajal in Trinitrobenzene Sulfonic Acid Induced Rat Colitis

    Institute of Scientific and Technical Information of China (English)

    Yan-cheng Dai; Zhi-peng Tang; Zhen-nan Wang; Ya-li Zhang; Xin-ying He

    2011-01-01

    Objective To observe the influence of Shenqing Recipe (SQR), a kind of Traditional Chinese Medicine, on the morphology and quantity of colonic interstitial cells of Cajal (ICC) in trinitrobenzene sulfonic acid (TNBS)-induced rat colitis, and to investigate the possible mechanism of SQR in regulating intestinal dynamics. Methods Sixty rats were randomly divided into normal control, model I , model Ⅱ, mesalazine,and high-dose, and low-dose SQR groups with 10 rats in each group. TNBS (10 mg) dissolved in 50% ethanol was instilled into the lumen of the rat colon of the latter five groups to induce colitis. On the 4th day after administration of TNBS, each treatment group was administered one of the following formulations by enteroclysis gavage once a day for 7 days: 600 mg·kg-1·d-1mesalazine, 2.4 g·kg-1·d-1 SQR, and 1.2 g·kg-1·d-1 SQR. Model Ⅱ rats received normal saline solution. After 7 days colonic samples were collected. While the colonic samples of model Ⅰ group were collected on the 3rd day after TNBS administered. Ultrastructure of ICC in the damaged colonic tissues was observed with transmission electron microscope. Expression of c-kit protein in colonic tissue was determined by immunohistochemical staining and Western blot. Results The ultrastructure of colonic ICC in the rat model of TNBS-induced colitis showed a severe injury, and administration of SQR or mesalazine reduced the severity of injury. Similarly, the expression of c-kit protein of TNBS-induced colitis rat model was significantly decreased compared with the normal control group (P<0.05). Treatment with SQR or mesalazine significantly increased the expression of c-kit protein compared with the administration of control formulations (P<0.05), especially the high-dose SQR group.Conclusion SQR could alleviate and repair the injured ICC, and improve its quantity, which might be involved in regulating intestinal motility.

  13. Analytical methodology for sulfonated lignins

    NARCIS (Netherlands)

    Brudin, S.; Schoenmakers, P.

    2010-01-01

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

  14. Risk factor benzene

    Energy Technology Data Exchange (ETDEWEB)

    Stobbe, H.

    1981-01-01

    Nearly one hundred years ago clinical and epidemiological studies have already assigned benzene as a markedly haematotoxic substance. Nowadays benzene is known as an important professional noxa, which is straight off directed against the haematopoietic system, essentially to a dose-time-effect. By this it can be taken as a model also for other noxious substances. Similar solvents often contain so-called 'hidden benzene', that means not declared benzene, so that the consumer doesn't know what dangerous substance are available for his personal use. Impairments caused by benzene mostly are manifested earliest after months, years or for tens of years, and the point is, that these haematopoietic disorders are irreversible disturbances of the haematopoietic stem cell compartment. The consequence of this fact is a deep involvement of the proliferation of the erythro-, mono-, granulo- and thrombopoietic cell lines, mostly with predominance of one of these myeloproliferative cell systems. In the further progression of the impairments due to benzene three different clinical pictures can be observed: the aplastic bone marrow syndrome (i.e. aplastic anemia), the haematopoietic dysplasia (i.e. preleukemia) and the acute leukemias (with the subtypes erythroleukosis, myeloblastic-promyelocytic or myelomonocytic from respectively). Also the transition from one clinical picture to another is possible.

  15. An efficient synthesis of substituted benzene-1,2-dicarboxaldehydes

    Institute of Scientific and Technical Information of China (English)

    ZHU Peter C; WANG Dei-Haw; LU Kaitao; MANI Neelakandha

    2007-01-01

    Substituted-benzene-1,2-dicarbaldehydes were synthesized by the reaction of substituted-1,2-bis (dibromomethyl) benzenes with fuming sulfuric acid, followed by hydrolysis, The yields were significantly improved by introducing solid sodium bicarbonate into the reaction mixture before hydrolysis and workup.

  16. An efficient synthesis of substituted benzene-1,2-dicarboxaldehydes

    Institute of Scientific and Technical Information of China (English)

    ZHU; Peter; C; WANG; Der-Haw; MANI; Neelakandha

    2007-01-01

    Substituted-benzene-1,2-dicarbaldehydes were synthesized by the reaction of substituted-1,2-bis(dibromomethyl) benzenes with fuming sulfuric acid,followed by hydrolysis. The yields were signifi-cantly improved by introducing solid sodium bicarbonate into the reaction mixture before hydrolysis and workup.

  17. Zwitterionic chiral stationary phases based on cinchona and chiral sulfonic acids for the direct stereoselective separation of amino acids and other amphoteric compounds.

    Science.gov (United States)

    Zhang, Tong; Holder, Emilie; Franco, Pilar; Lindner, Wolfgang

    2014-06-01

    An extensive series of free amino acids and analogs were directly resolved into enantiomers (and stereoisomers where appropriate) by HPLC on zwitterionic chiral stationary phases (Chiralpak ZWIX(+) and Chiralpak ZWIX(-)). The interaction and chiral recognition mechanisms were based on the synergistic double ion-paring process between the analyte and the chiral selectors. The chiral separation and elution order were found to be predictable for primary α-amino acids with apolar aliphatic side chains. A systematic investigation was undertaken to gain an insight into the influence of the structural features on the enantiorecognition. The presence of polar and/or aromatic groups in the analyte structure is believed to tune the double ion-paring equilibrium by the involvement of the secondary interaction forces such as hydrogen bonding, Van der Waals forces and π-π stacking in concert with steric parameters. The ZWIX chiral columns were able to separate enantiomers and stereoisomers of various amphoteric compounds with no need for precolumn derivatization. Column switching between ZWIX(+) and ZWIX(-) is believed to be an instrumental tool to reverse or control the enantiomers elution order, due to the complementarity of the applied chiral selectors.

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

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

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

  19. Cross-aldol Condensation of Cycloalkanones and Aromatic Aldehydes in the Presence of Nanoporous Silica-based Sulfonic Acid (SiO2-Pr-SO3H) under Solvent Free Conditions

    Institute of Scientific and Technical Information of China (English)

    MOHAMMADI ZIARANI Ghodsi; BADIEI Alireza; ABBASI Alireza; FARAHANI Zahra

    2009-01-01

    The aromatic aldehydes underwent cross aldol condensation with cycloalkanones in the presence of a catalytic amount of nanoporous silica-based sulfonic acid (SiO2-Pr-SO3H) under solvent-free conditions to afford the corresponding a,a'-bis(substituted benzylidene)cycloalkanones in excellent yields with short reaction time without any side reactions.This method is very general,simple and environmentally friendly in contrast with other existing methods.SiO2-Pr-SO3H was proved to be an efficient heterogeneous solid acid catalyst,which could be easily handled and removed from the reaction mixture by simple filtration,and also recovered and reused without loss of reactivity.

  20. Characteristics of the Carbon Nanotube Coated with Polyaniline Doped with Hydrochloric Acid and Dodecylbenzene Sulfonic Acid%盐酸与DBSA共掺杂聚苯胺修饰碳纳米管性能的研究

    Institute of Scientific and Technical Information of China (English)

    张爱波; 刘刚; 薛艳丽; 郑亚萍; 赵纯颖

    2011-01-01

    The MWNTs/polyaniline composites were prepared via in-situ emulsion polymerization using hydrochloric acid and dodecylbenzene sulfonic acid as dopants. The FTIR spectra, TEM and TGA were used to characterize the morphology and performance of the composites. The TEM results show that the surface of MWNTs are coated by polyaniline composites and the thickness of the coating layer is 10~20nm. The solubility is increased in DMF, THF and chloroform. The thermal stability of the composite is highly improved at 520~750℃ and the encapsulation rate is 15.16%. The conductivity of the sample is increased from 10-7S/cm to 10-3S/cm.%采用原位乳液聚合法制备了盐酸与十二烷基苯磺酸(DBSA)共掺杂聚苯胺/MWNTs复合材料.利用FTIR、TEM和TG等对复合材料的形貌和性能进行了表征.TEM结果表明苯胺共聚物包覆于碳纳米管表面,包覆厚度为10~20nm.复合材料在DMF、THF和氯仿中的溶解性大幅度提高,在520~750℃的热稳定性明显提高,包覆率为15.16%,电导率从聚苯胺的10-7A/cm增大到10-3S/cm.

  1. Voltammetric determination of dopamine in the presence of uric acid using a 2-hydroxy-1-(1-hydroxynaphthyl-2-azo-naphthalin-4-sulfonic acid modified glassy carbon electrode

    Directory of Open Access Journals (Sweden)

    ALI ASGHAR ENSAF

    2010-12-01

    Full Text Available A polymerized film of 2-hydroxy-1-(1-hydroxynaphthyl-2-azo-naphthalin-4-sulfonic acid (HHNANSA was prepared at the surface of a glassy carbon electrode by electropolymerization. The modified electrode was used for the simultaneous determination of dopamine (DA and uric acid (UA. The electrochemical behaviors of the compounds at the surface of the modified electrode were studied using cyclic voltammetry, chronoamperometry, and square wave voltammetry (SWV. The experimental results indicated that the modified electrode exhibited an efficient electrocatalytic activity towards the oxidation of DA and UA, with a peak separation of about 140 mV at pH 5.0. Using chronoamperometry, the catalytic reaction rate constant was measured and found to equal to 1.23×104 mol-1 L s-1. At pH 5.0, the catalytic peak currents linearly depended on the DA and/or UA concentrations in the range of 1.0–300 µmol L-1 DA (two linear segments with different slopes and 6.7–20 µmol L-1 UA, using SWV. The detection limits for DA and UA were 0.25 and 1.17 µmol L-1, respectively. The RSD % for 40.0 and 140.0 µmol L-1 DA were 1.9 and 2.2 %, respectively, whereas for 10.0 and 20.0 µmol L-1 UA, they were 1.8 and 1.2 %, respectively. The modified electrode showed good sensitivity, selectivity, and stability. It was successfully applied for the determination of DA and UA in real samples, such as drugs and urine.

  2. Genotoxicity of intermittent co-exposure to benzene and toluene in male CD-1 mice.

    Science.gov (United States)

    Wetmore, Barbara A; Struve, Melanie F; Gao, Pu; Sharma, Sheela; Allison, Neil; Roberts, Kay C; Letinski, Daniel J; Nicolich, Mark J; Bird, Michael G; Dorman, David C

    2008-06-17

    Benzene is an important industrial chemical. At certain levels, benzene has been found to produce aplastic anemia, pancytopenia, myeloblastic anemia and genotoxic effects in humans. Metabolism by cytochrome P450 monooxygenases and myeloperoxidase to hydroquinone, phenol, and other metabolites contributes to benzene toxicity. Other xenobiotic substrates for cytochrome P450 can alter benzene metabolism. At high concentrations, toluene has been shown to inhibit benzene metabolism and benzene-induced toxicities. The present study investigated the genotoxicity of exposure to benzene and toluene at lower and intermittent co-exposures. Mice were exposed via whole-body inhalation for 6h/day for 8 days (over a 15-day time period) to air, 50 ppm benzene, 100 ppm toluene, 50 ppm benzene and 50 ppm toluene, or 50 ppm benzene and 100 ppm toluene. Mice exposed to 50 ppm benzene exhibited an increased frequency (2.4-fold) of micronucleated polychromatic erythrocytes (PCE) and increased levels of urinary metabolites (t,t-muconic acid, hydroquinone, and s-phenylmercapturic acid) vs. air-exposed controls. Benzene co-exposure with 100 ppm toluene resulted in similar urinary metabolite levels but a 3.7-fold increase in frequency of micronucleated PCE. Benzene co-exposure with 50 ppm toluene resulted in a similar elevation of micronuclei frequency as with 100 ppm toluene which did not differ significantly from 50 ppm benzene exposure alone. Both co-exposures - 50 ppm benzene with 50 or 100 ppm toluene - resulted in significantly elevated CYP2E1 activities that did not occur following benzene or toluene exposure alone. Whole blood glutathione (GSH) levels were similarly decreased following exposure to 50 ppm benzene and/or 100 ppm toluene, while co-exposure to 50 ppm benzene and 100 ppm toluene significantly decreased GSSG levels and increased the GSH/GSSG ratio. The higher frequency of micronucleated PCE following benzene and toluene co-exposure when compared with mice exposed to

  3. Catalytic alcoholysis of cellulose into methyl levulinate using sulfonic heteropoly solid acid%磺酸型杂化固体酸催化纤维素醇解为乙酰丙酸甲酯

    Institute of Scientific and Technical Information of China (English)

    杨卫平; 王海军; 李炜; 徐岩杰; 陈仁举

    2016-01-01

    合成了磺酸型杂化固体酸1-(3-磺酸基)丙基-3-烃基咪唑磷钨酸盐(Cn IMPS)3 PW12 O40,并将其应用于催化纤维素的醇解反应之中。与无机酸、对甲苯磺酸(PTSA)以及磷钨酸相比,(C1 IMPS)3 PW12 O40表现出更佳的催化活性。通过单因素法对反应温度、时间、催化剂用量、固液比、加水量等进行考察,结果表明,m((C1 IMPS)3 PW12 O40)∶m(Cellulose)=0.4时,(C1 IMPS)3 PW12 O40在体系中浓度4.00 mg/mL,甲醇和4.0%体积分数的水混合溶剂,反应温度190℃,时间60 min,乙酰丙酸甲酯的产率最大为41.0%。反应结束后将体系置换为水相,调节反应体系的pH值约为2时,催化剂以固体沉淀的方式析出、回收,且经过5次重复利用后仍能保持良好的催化性能。%A kind of sulfonic heteropoly solid acid,(CnIMPS)3PW12O40 (1-(3-sulfonic acid)propyl-3-hy-drocarbon imidazole phosphotungstate),had been synthesized and applied to the catalytic alcoholysis of cellulose.Compared with inorganic acids,p-toluene sulfonic acid (PTSA ) and phosphotungstic acid, (C1IMPS)3PW12O40(1-(3-sulfonic acid)propyl-3-methyl imidazole phosphotungstate)showed better cat-alytic activity.By complete randomalized design,the effect factors of reaction,temperature,time,amount of catalyst,solid-liquid ratio,the amount of water,etc.,had been investigated and optimized in detail as fol-lows∶m ((C1IMPS)3PW12O40):m(Cellulose)=0.4,the concentration of (C1IMPS)3PW12O40 in the sys-tem is 4.00 mg/mL,and 4.0%volume fraction of water mixed methanol,60 min at 190 ℃,and the yield of methyl levulinate reached 41 .0%.After reaction,the solution was replaced with water,then adjusted the pH≈2,the catalyst could be recovered,which was reused for five times with good catalytic perform-ance still maintain.

  4. 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

  5. 阳离子结构对磺酸基离子液体酸强度的影响规律%Influence Rule of Cationic Structure on Acid Strength of Sulfonic Ionic Liquids

    Institute of Scientific and Technical Information of China (English)

    王睿; 罗辉; 范维玉; 薛凯; 南国枝

    2015-01-01

    Eight SO3 H‐functional Brønsted acidic ionic liquids(ILs) with different nitrogen function groups were prepared and their acid strengths were investigated by UV‐Hammett combined method with p‐nitroaniline as indicator .The results demonstrated that the acid strength of the ILs increased with the increase of their concentration , while their acidity order was irrelevant to the concentration .The acidity descend of the eight acidic ILs with different nitrogen groups was in the order of the IL with caprolactam group ,pyridine group ,N‐methyl imidazole group ,trimethylamine group ,respectively .For the ILs with same nitrogen functional group ,their acid strength increased with the alkyl chain being longer . Compared with the effect of alkyl chain length on the acid strength of IL , the effect of nitrogen functional group type was more obvious . In methanol , N‐(4‐sulfonic group) butyl‐hydrogen sulfate imidazole , N‐(4‐sulfonic group ) butyl‐caprolactam hydrogen sulfate , N‐(4‐sulfonic group ) butyl‐pyridine hydrogen sulfate , N‐(3‐sulfonic group ) propyl‐pyridine hydrogen sulfate , N‐(4‐sulfonic group ) butyl‐hydrogen sulfate imidazole and N‐(3‐sulfonic group) propyl‐hydrogen sulfate imidazole showed the character of super acid , however ,in water only the first five showed the character of super acid .%采用UV‐Hammett指示剂联用法,以对硝基苯胺为指示剂,考察了阴离子为硫酸氢根,阳离子分别为三乙胺、 N‐甲基咪唑、吡啶或己内酰胺上带有丙烷基磺酸或丁烷基磺酸的8种磺酸基功能化离子液体的酸强度。结果表明,同一种离子液体的浓度越大,其酸强度越大,但不同离子液体间的相对酸强度大小顺序与离子液体的浓度无关;含氮母体化合物不同的磺酸基离子液体按酸强度由大到小排列的顺序为己内酰胺类、吡啶类、咪唑类、三乙胺类,当含氮母体化合物相同时,

  6. Tracer Diffusion of Polystyrene in Lightly Sulfonated Polystyrene

    Science.gov (United States)

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

    2005-03-01

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

  7. New Stable Cu(I) Catalyst Supported on Weakly Acidic Polyacrylate Resin for Green C-N Coupling: Synthesis of N-(Pyridin-4-yl)benzene Amines and N,N-Bis(pyridine-4-yl)benzene Amines.

    Science.gov (United States)

    Kore, Nitin; Pazdera, Pavel

    2016-12-22

    A method for preparation of a new stable Cu(I) catalyst supported on weakly acidic polyacrylate resin without additional stabilizing ligands is described. A simple and efficient methodology for Ullmann Cu(I) catalyzed C-N cross coupling reactions using this original catalyst is reported. Coupling reactions of 4-chloropyridinium chloride with anilines containing electron donating (EDG) or electron withdrawing (EWG) groups, naphthalen-2-amine and piperazine, respectively, are successfully demonstrated.

  8. Proton-conducting membrane based on epoxy resin-poly(vinyl alcohol)-sulfosuccinic acid blend and its nanocomposite with sulfonated multiwall carbon nanotubes for fuel-cell application

    Science.gov (United States)

    Kakati, Nitul; Das, Gautam; Yoon, Young Soo

    2016-01-01

    A blend of poly(vinyl alcohol) (PVA) with diglycidyl ether of bisphenol-A (DGB) in the presence of sulfosuccinic acid (SSA) was investigated as hydrolytically-stable proton-conducting membrane. The PVA modification was carried out by varying the DGB:SSA ratio (20:20, 10:20, and 5:20). A nanocomposite of the blend (20:20) was prepared with sulfonated multiwall carbon nanotubes (viz., 1, 3 and 5 wt%). The water uptake behavior and the proton conductivity of the prepared membranes were evaluated. The ionic conductivity of the membranes and the water uptake behavior depended on the s-MWCNT and the DGB contents. The ionic conductivity showed an enhancement for the blend and for the nanocomposite membrane as compared to the pristine polymer.

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

    Science.gov (United States)

    Kishi, Takahiro; Arai, Mitsuru

    2008-11-15

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-01-15

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

  11. 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).

  12. 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.

  13. Synthesis and characterization of binary and ternary complexes of Co(II), Ni(II), Cu(II) and Zn(II) ions based on 4-aminotoluene-3-sulfonic acid

    Science.gov (United States)

    Faheim, Abeer A.; Abdou, Safaa N.; Abd El-Wahab, Zeinab H.

    2013-03-01

    Salicylidene (4-aminotoluene-3-sulfonic acid) Schiff base ligand H2L, and its binary and ternary Co(II), Ni(II), Cu(II) and Zn(II) complexes using 8-hydroxyquinoline (8-HOqu) and 2-aminopyridine (2-Ampy) as secondary ligands have been synthesised and characterized via elemental analysis, spectral data (IR, 1H NMR, mass and solid reflectance), molar conductance, magnetic moment, TG-DSC measurements and XRPD analysis. Correlation of all spectroscopic data suggest that H2L ligand acts as monoanionic terdentate ligand with ONO sites coordinating to the metal ions via deprotonated phenolic-O, azomethine-N and sulfonate-O while 2-Ampy behaves as a neutral monodentate ligand via amino group-N and 8-HOqu behaves as a monoanionic bidentate ligand through the ring-N and deprotonated phenolic-O. The thermal behavior of these complexes shows that the coordinated water molecules were eliminated from the complexes at relatively higher temperatures than the hydrated water and there are two routes in removal of coordinated water molecules. All complexes have mononuclear structure and the tetrahedral, square planar or an octahedral geometry have been proposed. The ligand and its complexes have been screened for their antimicrobial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Salmonella typhimurium, Candida albicans and Aspergillus fumigatus. Among the synthesised compounds, the binary and ternary Ni(II) complexes, (2, 8 and 10) and ternary Zn(II) complex, (12) were found to be very effective against Candida albicans and Bacillus subtilis than all other complexes with MICs of 2 and 8 μg/mL, respectively.

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

    NARCIS (Netherlands)

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

    2000-01-01

    Homogeneuosly sulfonated poly(styrene) (SPS) was prepared with various concentration of sulfonic acid groups in the base polymer. Membranes cast from these materials were investigated in relation to proton conductivity and methanol permeability in the temperature range from 20°C to 60°C. It was foun

  15. 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)

  16. A physiological model for simulation of benzene metabolism by rats and mice.

    Science.gov (United States)

    Medinsky, M A; Sabourin, P J; Lucier, G; Birnbaum, L S; Henderson, R F

    1989-06-15

    Studies conducted by the National Toxicology Program on the chronic toxicity of benzene indicated that B6C3F1 mice are more sensitive to the toxic effects of benzene than are F344 rats. A physiological model was developed to describe the uptake and metabolism of benzene in rats and mice and to determine if the observed differences in toxic effects could be explained by differences in the pathways for metabolism of benzene or by differences in uptake of benzene. Major pathways for elimination of benzene included metabolism to hydroquinone glucuronide or hydroquinone sulfate, phenyl glucuronide or phenyl sulfate, muconic acid, and prephenyl mercapturic acid or phenyl mercapturic acid. Model simulations for total benzene metabolized and for profiles of benzene metabolites were conducted for oral or inhalation exposure and compared to data for urinary excretion of benzene metabolites after exposure of rats and mice to [14C]- or [3H]-benzene by inhalation or gavage. Results for total amount of benzene metabolized, expressed per kilogram body weight, indicated that for inhalation exposure concentrations up to 1000 ppm, mice metabolized at least two to three times as much benzene as did rats. Simulations of oral exposure to benzene resulted in more benzene metabolized per kilogram body weight by rats at oral exposures of greater than 50 mg/kg. Patterns of metabolites formed after either route of exposure were very different for F344/N rats and B6C3F1 mice. Rats primarily formed the detoxification metabolite, phenyl sulfate. Mice formed hydroquinone glucuronide and muconic acid in addition to phenyl sulfate. Hydroquinone and muconic acid are associated with pathways leading to the formation of the putative toxic metabolites of benzene. Metabolic rate parameters, Vmax and Km, were very different for hydroquinone conjugate and muconic acid formation compared to formation of phenyl conjugates and phenyl mercapturic acids. Putative toxication pathways could be characterized as

  17. Syntheses, structures, and properties of Co(II)/Zn(II) mixed-ligand coordination polymers based on 4-[(3,5-dinitrobenzoyl)amino]benzoic acid and 1,4-bis(1-imidazolyl) benzene

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Fei; Chen, Jing; Liang, Yongfeng [Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018 (China); Zou, Yang, E-mail: zouyang@zstu.edu.cn [Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018 (China); Yinzhi, Jiang [Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018 (China); Xie, Jingli, E-mail: jlxie@mail.zjxu.edu.cn [College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, Zhejiang 314001 (China)

    2015-05-15

    Two coordination polymers [Co(dnbab){sub 2}(bimb)](H{sub 2}O){sub 4} (1) and [Zn(dnbab){sub 2}(bimb)](H{sub 2}O){sub 5} (2) (Hdnbab=4-[(3,5-dinitrobenzoyl)amino]benzoic acid, bimb=1,4-bis(1-imidazolyl) benzene) have been solvothermally synthesized. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by powder X-ray diffraction (PXRD) and thermogravimetric (TG) analyses. Complexes 1 and 2 are isostructures and each displays an one-dimensional (1D) zigzag chain, which further forms a 3D supramolecular architecture with 1-D channels via inter-chain π–π interactions and hydrogen bonds. Moreover, the magnetic properties of 1 and fluorescent properties of 2 have been investigated. - Graphical abstract: Two coordination supramolecular frameworks [Co(dnbab){sub 2}(bimb)](H{sub 2}O){sub 4}(1) and [Zn(dnbab){sub 2}(bimb)](H{sub 2}O){sub 5}(2) (Hdnbab=4-[(3,5-dinitrobenzoyl)amino]benzoic acid, bimb=1,4-bis(1-imidazolyl) benzene) have been synthesized and characterized by X-ray single-crystal diffraction. Their thermal, magnetic and fluorescent properties have also been studied. - Highlights: • Two isomorphic Co(II)/Zn(II) complexes with the mixed-ligands have been synthesized. • Hydrogen bonds and π–π stacking interactions directed the final 3-D architecture assembly. • Both Co(II) and Zn(II) complexes show good thermal stability. • Co complex exhibits antiferromagnetic interaction. • The fluorescent property of Zn(II) complex has been investigated in the solid state.

  18. Sulfonate-modified phenylboronic acid-rich nanoparticles as a novel mucoadhesive drug delivery system for vaginal administration of protein therapeutics: improved stability, mucin-dependent release and effective intravaginal placement

    Directory of Open Access Journals (Sweden)

    Li CY

    2016-11-01

    Full Text Available ChunYan Li,1 ZhiGang Huang,2 ZheShuo Liu,1 LiQian Ci,3 ZhePeng Liu,3 Yu Liu,2 XueYing Yan,1 WeiYue Lu2 1School of Pharmacy, Heilongjiang University of Chinese Medicine, Harbin, 2Department of Pharmaceutics, School of Pharmacy, Key Laboratory of Smart Drug Delivery, Ministry of Education, Fudan University, 3School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, People’s Republic of China Abstract: Effective interaction between mucoadhesive drug delivery systems and mucin is the basis of effective local placement of drugs to play its therapeutic role after mucosal administration including vaginal use, which especially requires prolonged drug presence for the treatment of gynecological infectious diseases. Our previous report on phenylboronic acid-rich nanoparticles (PBNPs demonstrated their strong interaction with mucin and mucin-sensitive release profiles of the model protein therapeutics interferon (IFN in vitro, but their poor stability and obvious tendency to aggregate over time severely limited future application. In this study, sulfonate-modified PBNPs (PBNP-S were designed as a stable mucoadhesive drug delivery system where the negative charges conferred by sulfonate groups prevented aggregation of nanoparticles and the phenylboronic acid groups ensured effective interaction with mucin over a wide pH range. Results suggested that PBNP-S were of spherical morphology with narrow size distribution (123.5 nm, polydispersity index 0.050, good stability over a wide pH range and 3-month storage and considerable in vitro mucoadhesion capability at vaginal pH as shown by mucin adsorption determination. IFN could be loaded to PBNP-S by physical adsorption with high encapsulation efficiency and released in a mucin-dependent manner in vitro. In vivo near-infrared fluorescent whole animal imaging and quantitative vaginal lavage followed by enzyme-linked immunosorbent assay (ELISA assay of

  19. Ion Exchange and Antibiofouling Properties of Poly(ether sulfone) Membranes Prepared by the Surface Immobilization of Brønsted Acidic Ionic Liquids via Double-Click Reactions.

    Science.gov (United States)

    Yi, Zhuan; Liu, Cui-Jing; Zhu, Li-Ping; Xu, You-Yi

    2015-07-28

    Brønsted acidic ionic liquids (BAILs) are unique ionic liquids that display chemical structures similar to zwitterions, and they were typically used as solvents and catalysts. In this work, an imidazole-based BAIL monolayer was fabricated onto poly(ether sulfone) (PES) membranes via surface clicking reactions, and the multifunctionality, including ion exchange and biofouling resistance to proteins and bacteria, was demonstrated, which was believed to be one of few works in which BAIL had been considered to be a novel fouling resistance layer for porous membranes. The successful immobilization of the BAILs onto a membrane surface was confirmed by X-ray photoelectron spectroscopy analysis, contact angle measurement, and ζ potential determination. The results from Raman spectroscopy showed that, as a decisive step prior to zwitterion, the BAIL was deprotonated in aqueous solution, and biofouling resistance to proteins and bacteria was found. However, BAIL displayed ion exchange ability at lower pH, and surface hydrophilicity/hydrophobicity of membranes could be tuned on purpose. Our results have demonstrated that the BAIL grafted onto membranes will not only act as an antibiofouling barrier like zwitterions but also provide a platform for surface chemical tailoring by ion exchange, the property of which will become especially important in acidic solutions where the fouling resistance performances of zwitterions are greatly weakened.

  20. EFFECTIVENESS OF WASTE STABILIZATION PONDS IN REMOVAL OF LINEAR ALKYL BENZENE SALFONATE (LAS)

    OpenAIRE

    2013-01-01

    Detergents contain synthetic or organic surface active agents called surfactants, which are derived from petroleum product precursors. They have the common property of lowering the surface tensions of water thus allowing dirt or grease adhered to various articles to be washed off. Linear alkyl benzene sulfonate (LAS) is a most commonly used anionic surfactant. Discharge of raw or treated wastewater containing this chemical substance into the environment causes major public health and envirome...

  1. Biomarkers of internal dose for the assessment of environmental exposure to benzene.

    Science.gov (United States)

    Lovreglio, Piero; D'Errico, Maria Nicolà; Fustinoni, Silvia; Drago, Ignazio; Barbieri, Anna; Sabatini, Laura; Carrieri, Mariella; Apostoli, Pietro; Soleo, Leonardo

    2011-10-01

    The urinary excretion of t,t-muconic acid (t,t-MA), S-phenylmercapturic acid (SPMA) and urinary benzene and the influence of a smoking habit and of exposure to urban traffic on the urinary excretion of these biomarkers were investigated in 137 male adults from the general population. All subjects were not occupationally exposed to benzene and resident in two cities in Puglia (Southern-Italy). Environmental exposure to benzene was measured using passive personal samplers. The biomarkers t,t-MA, SPMA and urinary benzene were determined in urine samples collected from each subject at the end of the environmental sampling. The percentage of cases above the limit of detection was higher for SPMA and urinary benzene in smokers than in non-smokers, and for airborne benzene and urinary benzene in subjects exposed to urban traffic. Airborne benzene was correlated with the time spent in urban traffic during the environmental sampling. Among the biomarkers, urinary benzene was found to be correlated with airborne benzene only in non-smokers, and with the time spent in urban traffic, both in smokers and non-smokers considered together, and in non-smokers only. Finally, multiple regression analysis showed that the urinary excretion of all the biomarkers was dependent on the number of cigarettes smoked per day and, for urinary benzene, also on the time spent in urban traffic. In conclusion, urinary benzene seems to be a more valid biomarker than t,t-MA and SPMA to assess environmental exposure to extremely low concentrations of benzene. Cigarette smoking prevailed over traffic exhaust fumes in determining the internal dose of benzene.

  2. [Preparation and application of solid phase extraction packing of zirconia microsphere coated with sulfonated crosslinked polystyrene].

    Science.gov (United States)

    Shen, Shuchang; Liu, Yuhui; Xiao, Xiaoxing

    2013-08-01

    Zirconia microsphere was prepared by polymerization-induced colloid aggregation (PICA) method and carbon-carbon double bond was grafted onto its surface by titanic acid ester coupling reagent. Poly(styrene-divinylbenzene) was synthesized by free radical polymerization by using styrene, divinylbenzene and carbon-carbon double bond on the microsphere surface in solution system, so the polymer was coated on the microsphere surface. After the benzene ring of the polymer was sulfonated, the cation exchange packing for solid phase extraction (SPE) was obtained. The material was characterized by Fourier transform infrared spectroscopy, scanning electron microscope and X-ray energy dispersive spectroscopy. Three herbicides of mesotrione, atrazine and acetochlor in water were determined by the SPE cartridge coupled with high performance liquid chromatography (HPLC). In the range of 0.5 - 3.0 mg/L, the relationships between the peak areas and mass concentrations of mesotrione, atrazine and acetochlor were linear with the correlation coefficients of 0.9936, 0.9925, 0.9919, respectively. The limits of detection were 5.41, 6.72 and 13.4 microg/L for mesotrione, atrazine and acetochlor, respectively. The results showed that the zirconium dioxide microspheres coated with polymer have diameters in the range of about 6 to 8 microm, the SPE cartridges of which have high adsorption rate for the targets.

  3. 三硝基苯磺酸诱导的慢性胰腺炎模型在疼痛研究中的应用%Application of trinitrobenze sulfonic acid-induced chronic pancreatitis rat model in pain study

    Institute of Scientific and Technical Information of China (English)

    王锋; 沈佳庆; 王兴鹏

    2012-01-01

    Objective To evaluate the application of chronic pancreatitis (CP) model induced by trinitrobenze sulfonic acid (TNBS) in pain study. Methods CP was induced by intraductual infusion of 2% TNBS in rats. Histopathological examination and serum amylase and lipase measurement were performed for the validation of CP. Pain resulting from CP was studied as abdominal sensitivity to Von Frey Filament stimulation on week 1,2,3 and 4 after the induction of CP. Results Progressive fibrosis and parenchyma injury were observed in tissue sections after 4 weeks of TNBS treatment. Abdominal pain was observed in TNBS treated rats and the severity was increased over time. Conclusion The rat CP model induced by TNBS is suitable in pain study.%目的 探讨三硝基苯磺酸(trinitrobenze sulfonic acid,TNBS)建立的慢性胰腺炎(chronic pancreatitis,CP)模型在CP腹痛研究中的适用性.方法 2% TNBS逆行胆胰管灌注建立大鼠CP模型.观察血清淀粉酶、脂肪酶和组织学以评价造模是否成功.Von Frey Filament测试检测不同时间点(1、2、3和4周)大鼠腹部的阳性反应,进而推测大鼠胰腺疼痛的改变.结果 TNBS处理4周后,大鼠胰腺出现实质损伤和进行性纤维化,具有CP的组织病理学改变.Von Frey Filament检测显示CP造模后,随着时间推移,大鼠腹部阳性反应逐渐增加.结论 TNBS不但适用于CP动物模型的建立,而且还适用于CP疼痛的基础研究.

  4. Preparation of a Sulfonated Carbonaceous Material from Lignosulfonate and Its Usefulness as an Esterification Catalyst

    Directory of Open Access Journals (Sweden)

    Duckhee Lee

    2013-07-01

    Full Text Available Sulfonated carbonaceous material useful as a solid acid catalyst was prepared from lignosulfonate, a waste of the paper-making industry sulfite pulping process, and characterized by 13C-NMR, FT-IR, TGA, SEM and elemental analysis, etc. The sulfonic acid group density and total density of all acid groups in the sulfonated carbonaceous material was determined by titration to be 1.24 mmol/g and 5.90 mmol/g, respectively. Its catalytic activity in the esterification of cyclohexanecarboxylic acid with anhydrous ethanol was shown to be comparable to that of the ionic exchange resin Amberlyst-15, when they were used in the same amount. In the meantime, the sulfonic acid group was found to be leached out by 26%–29% after it was exposed to hot water (95 °C for 5 h. The catalytic usefulness of the prepared carbonaceous material was investigated by performing esterifications.

  5. 丙烯腈-苯乙烯磺酸共聚物/层状双金属氢氧化物纳米复合质子传导聚合物电解质的制备与表征%Synthesis and characterization of proton-conducting polymer electrolytes based on acrylonitrile-styrene sulfonic acid copolymer/layered double hydroxides nanocomposites

    Institute of Scientific and Technical Information of China (English)

    王盎然; 包永忠; 翁志学; 黄志明

    2008-01-01

    Acrylonitrile-sodium styrene sulfonate copolymer/layered double hydroxides nanocomposites were prepared by in situ aqueous precipitation copolymerization of acrylonitrile (AN) and sodium styrene sulfonate (SSS) in the presence of 4-vinylbenzene sulfonate intercalated layered double hydroxides (MgAl-VBS LDHs) and transferred to acrylonitrile-styrene sulfonic acid (AN-SSA) copolymer/LDHs nanocomposites as a proton-conducting polymer electrolyte. MgAl-VBS LDHs were prepared by a coprecipitation method, and the structure and composition of MgAl-VBS LDHs were determined by X-ray diffraction (XRD), infrared spectroscopy, and elemental analysis. X-ray diffraction result of AN-SSS copolymer/LDHs nanocomposites indicated that the LDHs layers were well dispersed in the AN-SSS copolymer matrix. All the AN-SSS copolymer/LDHs nanocomposites showed significant enhancement of the decomposition temperatures compared with the pristine AN-SSS copolymer, as identified by the thermogravimetric analysis. The methanol crossover was decreased and the proton conductivity was highly enhanced for the AN-SSA copolymer/LDHs nanocomposite electrolyte systems In the case of the nanocomposite electrolyte containing 2% (by mass) LDHs, the proton conductivity of 2.60×10-3 S·m-1 was achieved for the polymer electrolyte.

  6. Monitoring low benzene exposure: comparative evaluation of urinary biomarkers, influence of cigarette smoking, and genetic polymorphisms.

    Science.gov (United States)

    Fustinoni, Silvia; Consonni, Dario; Campo, Laura; Buratti, Marina; Colombi, Antonio; Pesatori, Angela C; Bonzini, Matteo; Bertazzi, Pier A; Foà, Vito; Garte, Seymour; Farmer, Peter B; Levy, Leonard S; Pala, Mauro; Valerio, Federico; Fontana, Vincenzo; Desideri, Arianna; Merlo, Domenico F

    2005-09-01

    Benzene is a human carcinogen and an ubiquitous environmental pollutant. Identification of specific and sensitive biological markers is critical for the definition of exposure to low benzene level and the evaluation of the health risk posed by this exposure. This investigation compared urinary trans,trans-muconic acid (t,t-MA), S-phenylmercapturic acid, and benzene (U-benzene) as biomarkers to assess benzene exposure and evaluated the influence of smoking and the genetic polymorphisms CYP2E1 (RsaI and DraI) and NADPH quinone oxidoreductase-1 on these indices. Gas station attendants, urban policemen, bus drivers, and two groups of controls were studied (415 subjects). Median benzene exposure was 61, 22, 21, 9 and 6 microg/m(3), respectively, with higher levels in workers than in controls. U-benzene, but not t,t-MA and S-phenylmercapturic acid, showed an exposure-related increase. All the biomarkers were strongly influenced by cigarette smoking, with values up to 8-fold higher in smokers compared with nonsmokers. Significant correlations of the biomarkers with each other and with urinary cotinine were found. A possible influence of genetic polymorphism of CYP2E1 (RsaI and/or DraI) on t,t-MA and U-benzene in subjects with a variant allele was found. Multiple linear regression analysis correlated the urinary markers with exposure, smoking status, and CYP2E1 (RsaI; R(2) up to 0.55 for U-benzene). In conclusion, in the range of investigated benzene levels (<478 micro/m(3) or <0.15 ppm), smoking may be regarded as the major source of benzene intake; among the study indices, U-benzene is the marker of choice for biomonitoring low-level occupational and environmental benzene exposure.

  7. 并联式双梯度反相离子对液相色谱法快速检测土壤中芳磺酸%The Rapid Detection of Seven Kinds of Aromatic Sulfonic Acid in Soil by Parallel and Dual Ion-Pair RP-HPLC Gradient Elution Method

    Institute of Scientific and Technical Information of China (English)

    杨柳; 马浩; 李桂香; 贺伟; 施超欧

    2014-01-01

    Established a method for extraction and fast detection of 7 kinds of aromatic sulfonic acid ( anthraquinone 1, 5-disulfonic acid, 1-amino-8-naphthol-3, 6-disulfonic acid, 1-naphthol-4-sulfonic, anthraquinone-1, 8-disulfonic acid, 1-naphthalene sulfonic acid, 2-naphthalene sulfonic acid, 3-hydroxy-2-naphthoic acid) in soil by valve switching Ion-pair RP-HPLC with a dual system. Two columns were used in this system. When one was in the process of determination, the other one was in the process of equilibration. Thus 38�5% time was saved. Analytical columns were Dikma Diamonsil C18 (150 mm × 4�6 mm × 5 μm) , eluents were ion-pair reagent ( Tetrabutylammonium Hydrogen Sulfate ) and acetonitrile, and wave lengths were 226, 235, 258 nm. A good linear relationship was obtained for each aromatic sulfonic acid. All linear correlation coefficients were more than 0�999 9. Extracted and detected the randomly selected samples, and got each RSD of the 7 compounds less than 7% as well as the quantification limit no more than 0�181 2 μg/g. Both of the repeatability and quantification limit meet the requirements of detection.%通过阀切换并联式双系统,建立了一套测定土壤样品中7种芳磺酸的反相离子对液相色谱法。该方法采用2根色谱柱,一根色谱柱分析的同时,另一根色谱柱通过阀切换实现平衡,节约了38�5%的分析时间。方法使用 Dikma Diamonsil C18(150 mm ×4�6 mm ×5μm)色谱柱,以离子对试剂(四丁基硫酸氢铵)和乙腈为流动相,检测波长为226、235、258 nm。各组分线性关系良好,线性相关系数均在0�9999以上。随机抽取样品进行重新提取、检测,得到各组分的相对标准偏差均小于7%,且定量限最高不超过0�1812μg/g,重复性和定量限均能满足实验要求。

  8. Simultaneous determination of cysteine, uric acid and tyrosine using Au-nanoparticles/poly(E)-4-(p-tolyldiazenyl)benzene-1,2,3-triol film modified glassy carbon electrode

    Energy Technology Data Exchange (ETDEWEB)

    Taei, M., E-mail: m.taei@ch.iut.ac.ir; Hasanpour, F.; Salavati, H.; Banitaba, S.H.; Kazemi, F.

    2016-02-01

    A novel Au nanoparticles/poly(E)-4-(p-tolyldiazenyl)benzene-1,2,3-triol (AuNPs/PTAT) film modified glassy carbon electrode (AuNPs/PTAT/GCE) was fabricated for the simultaneous determination of three antioxidants named, cysteine (Cys), uric acid (UA) and tyrosine (Tyr). The bare glassy carbon electrode (GCE) fails to separate the oxidation peak potentials of these molecules, while PTAT film modified electrode can resolve them. Electrochemical impedance spectroscopy (EIS) study indicates that the charge transfer resistance of bare electrode increased as (E)-4-(p-tolyldiazenyl)benzene-1,2,3-triol was electropolymerized at the bare electrode. Furthermore, EIS exhibits enhancement of electron transfer kinetics between analytes and electrode after electrodeposition of Au nanoparticles. Differential pulse voltammetry results show that the electrocatalytic current increases linearly in the ranges of 2–540 μmol L{sup −1} for Cys, 5–820 μmol L{sup −1} for UA and 10–560 μmol L{sup −1} for Tyr with detection limits (S/N = 3) of 0.04 μmol L{sup −1}, 0.1 μmol L{sup −1} and 2 μmol L{sup −1} for Cys, UA and Tyr, respectively. The proposed method was successfully applied for simultaneous determination of Cys, UA and Tyr in human urine samples. - Highlights: • AuNPs/PTAT/GCE was fabricated by electrodeposition and electropolymerization. • The sensor reduced the overpotential for oxidation of Cys. • This electrode was successfully used for simultaneous sensing of Cys, UA and Tyr. • This sensor was effectively used for detection Cys, UA and Tyr in real samples.

  9. Fuel Dependence of Benzene Pathways

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, H; Eddings, E; Sarofim, A; Westbrook, C

    2008-07-14

    The relative importance of formation pathways for benzene, an important precursor to soot formation, was determined from the simulation of 22 premixed flames for a wide range of equivalence ratios (1.0 to 3.06), fuels (C{sub 1}-C{sub 12}), and pressures (20 to 760 torr). The maximum benzene concentrations in 15 out of these flames were well reproduced within 30% of the experimental data. Fuel structural properties were found to be critical for benzene production. Cyclohexanes and C{sub 3} and C{sub 4} fuels were found to be among the most productive in benzene formation; and long-chain normal paraffins produce the least amount of benzene. Other properties, such as equivalence ratio and combustion temperatures, were also found to be important in determining the amount of benzene produced in flames. Reaction pathways for benzene formation were examined critically in four premixed flames of structurally different fuels of acetylene, n-decane, butadiene, and cyclohexane. Reactions involving precursors, such as C{sub 3} and C{sub 4} species, were examined. Combination reactions of C{sub 3} species were identified to be the major benzene formation routes with the exception of the cyclohexane flame, in which benzene is formed exclusively from cascading fuel dehydrogenation via cyclohexene and cyclohexadiene intermediates. Acetylene addition makes a minor contribution to benzene formation, except in the butadiene flame where C{sub 4}H{sub 5} radicals are produced directly from the fuel, and in the n-decane flame where C{sub 4}H{sub 5} radicals are produced from large alkyl radical decomposition and H atom abstraction from the resulting large olefins.

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

    Science.gov (United States)

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

    2010-11-01

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

  11. Production of sulfonated cation-exchangers from petroleum asphaltites

    Energy Technology Data Exchange (ETDEWEB)

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

    1982-02-10

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

  12. Cyclic Reaction of lsobutyraldehyde Catalyzed by Biomass Char Sulfonic Acid%生物质炭磺酸催化异丁醛环化反应

    Institute of Scientific and Technical Information of China (English)

    刘贤响; 丁慧; 匡湘铭; 肖家福; 舒涛; 苏胜培; 尹笃林

    2015-01-01

    以樟树枝为原料,将其炭化后再磺化,制备了一种新型生物质炭基磺酸催化剂.利用红外光谱和热重分析等方法对其进行了表征.研究了该催化剂在异丁醛环化反应中的催化性能,系统考察了反应温度、反应时间、催化剂用量等因素对反应产物2,4,6-三异丙基-1,3,5-三氧噁烷收率的影响.实验结果表明:在反应温度25℃,催化剂用量为异丁醛质量的2%,反应时间2.5 h时,2,4,6-三异丙基-1,3,5-三氧噁烷的收率可达90.7%.樟树枝炭磺酸在异丁醛环化三聚反应中具有较好的催化效果和重复使用性能.%Biomzss czrbon-bzsed sulfonic zcid cztzlyst wzs prepzred with brznch of Cinnzmomum zs rzw mz-terizl. Thermzl stzbility znd surfzce composition of the solid zcid were determined by mezns of FT-IR znd TG. The zctivity of the cztzlyst wzs evzluzted by cyclic rezction of isobutyrzldehyde. Effects of rezction temperzture znd time znd cztzlyst zmount on product yield of 2,4,6-triisopropyl-1,3,5-trioxzne were investigzted. Experimentzl results show thzt the yield of 2 ,4 ,6-triisopropyl-1 ,3 ,5-trioxzne zmounts to 90 . 7% when rezction temperzture is 25℃,the zmount of cztzlyst is 2% of isobutyrzldehyde mzss,znd rezction time is 2. 5 h. The cztzlytic zctivity of the sulfonzt-ed bzmboo chzr in cyclic rezction of isobutyrzldehyde wzs good.

  13. Synthesis and characterization of sulfonic acid membranes based on interpenetrating polymer networks for application in fuel cells; Sintese e caracterizacao de membranas sulfonadas baseadas em redes polimericas interpenetrantes para aplicacao em celulas a combustivel

    Energy Technology Data Exchange (ETDEWEB)

    Blanco, Lyzed Toloza; Loureiro, Felipe A.M.; Rocco, Ana Maria [Grupo de Materiais Condutores e Energia, Escola de Quimica, Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil)], e-mail: amrocco@eq.ufrj.br; Pereira, Robson Pacheco [Instituto de Ciencias Exatas, Universidade Federal Fluminense (UFF), Volta Redonda, RJ (Brazil)

    2011-07-01

    In the present work, the synthesis and characterization of sulfonic membranes based on interpenetrating polymer networks (IPN). In order to obtain such systems, the diglycidyl ether of bisphenol A (DGEBA) was polymerized in presence of polyethyleneimine (PEI). These membranes were submitted to sulfonation reactions, originating IPN-SO{sub 3}H membranes. The characterization by FTIR evidenced the formation of a Semi-IPN structure, while sulfonation reactions resulted in systems containing -SO{sub 3}H groups covalently bonded to the chains. The membranes exhibited water retention up to 200 degree C, in a temperature range sufficient for application in PEMFC under hydration. (author)

  14. Flame Atomic Absorption Spectrometric Determination of Trace Metal Ions in Environmental and Biological Samples After Preconcentration on a Newly Developed Amberlite XAD-16 Chelating Resin Containing p-Aminobenzene Sulfonic Acid.

    Science.gov (United States)

    Islam, Aminul; Ahmad, Akil; Laskar, Mohammad Asaduddin

    2015-01-01

    Amberlite® XAD-16 was functionalized with p-aminobenzene sulfonic acid via an azo spacer in order to prepare a new chelating resin, which was then characterized by water regain value, hydrogen ion capacity, elemental analyses, and IR spectral and thermal studies. The maximum uptake of Cu(II), Ni(II), Zn(II), Co(II), Cr(III), Fe(III), and Pb(II) ions was observed in the pH range 4.0-6.0 with the corresponding half-loading times of 6.5, 7.0, 8.0, 9.0, 11.0, 8.5, and 16.5 min. The sorption data followed Langmuir isotherms and a pseudo-second-order model. Thermodynamic quantities, ΔH and ΔS, based on the variation of the distribution coefficient with temperature were also evaluated. High preconcentration factors of 60-100 up to a low preconcentration limit of 4.0-6.6 μg/L have been achieved for the metal ions. The validity of the method was checked by analyzing standard reference materials and recoveries of trace metals after spiking. The analytical applications of the method were explored by analyzing natural water, mango pulp, mint leaves, and fish.

  15. Dynamics of Sulfonated Polystyrene Ionomers by Dielectric Relaxation Spectroscopy

    Science.gov (United States)

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

    2010-03-01

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

  16. Surface Sulfonation of Polyvinyl Chloride by Plasma for Antithrombogenicity

    Institute of Scientific and Technical Information of China (English)

    刘鹏; 陈亚芍

    2004-01-01

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

  17. 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)

  18. Brain region-specific perfluoroalkylated sulfonate (PFSA) and carboxylic acid (PFCA) accumulation and neurochemical biomarker Responses in east Greenland polar Bears (Ursus maritimus)

    DEFF Research Database (Denmark)

    Pedersen, Kathrine Eggers; Basu, Niladri; Letcher, Robert;

    2015-01-01

    ), acetylcholinesterase (AChE) and glutamine synthetase (GS)) and receptor density (dopamine-2 (D2), muscarinic cholinergic (mAChR) and gamma-butyric acid type A (GABA-A)) along with PFSA and PFCA concentrations. Average brain ∑PFSA concentration was 25ng/g ww where PFOS accounted for 91%. Average ∑PFCA concentration...

  19. Heat-activated persulfate oxidation of PFOA, 6:2 fluorotelomer sulfonate, and PFOS under conditions suitable for in-situ groundwater remediation.

    Science.gov (United States)

    Park, Saerom; Lee, Linda S; Medina, Victor F; Zull, Aaron; Waisner, Scott

    2016-02-01

    PFOA (perfluorooctanoic acid) oxidation (0.121-6.04 μM) by heat-activated persulfate was evaluated at 20-60 °C with 4.2-84 mM [Formula: see text] and in the presence of soluble fuel components to assess feasibility for in-situ remediation of groundwater. 6:2 fluorotelomer sulfonic acid/sulfonate (6:2 FTSA) and PFOS (perfluorooctanesulfonic acid) persulfate oxidation was also evaluated in a subset of conditions given their co-occurrence at many sites. High performance liquid chromatography electron spray tandem mass spectrometry was used for organic analysis and fluoride was measured using a fluoride-specific electrode. PFOA pseudo-1st order transformation rates (k1,PFOA) increased with increasing temperature (half-lives from 0.1 to 7 d for 60 to 30 °C) sequentially removing CF2 groups ('unzipping') to shorter chain perfluoroalkyl carboxylic acids (PFCAs) and F(-). At 50 °C, a 5-fold increase in [Formula: see text] led to a 5-fold increase in k1,PFOA after which self-scavenging by sulfate radicals decreased the relative rate of increase with more [Formula: see text] . Benzene, toluene, ethylbenzene and xylene did not affect k1,PFOA even at 40 times higher molar concentrations than PFOA. A modeling approach to explore pathways strongly supported that for 6:2 FTSA, both the ethyl linkage and CF2-CH2 bond of 6:2 FTSA oxidize simultaneously, resulting in a ratio of ∼25/75 PFHpA/PFHxA. The effectiveness of heat-activated [Formula: see text] on PFOA oxidation was reduced in a soil slurry; therefore, repeated persulfate injections are required to efficiently achieve complete oxidation in the field. However, PFOS remained unaltered even at higher activation temperatures, thus limiting the sole use of heat-activated persulfate for perfluoroalkyl substances removal in the field.

  20. Synthesis and Crystal Structure of a Novel 2D Cadmium(Ⅱ) Complex Constructed from N-(3-Carboxyphenyl)-4,4'-bipyridinium and Benzene-1,4-dicarboxylic Acid

    Institute of Scientific and Technical Information of China (English)

    WU Wei; JIN Xu-Hui; JU Zhang-Feng; ZHANG Jie

    2008-01-01

    A novel redox-active bipyridinium ligand N-(3-carboxyphenyl)-4,4'-bipyridinium chloride (HCPBPyCl) and its coordination polymer {[Cd2(CPBPy)2(BDC)(H2O)2Cl2]·6H2O}n 1 (H2BDC = benzene-1,4-dicarboxylic acid) were synthesized and characterized. Crystallographic data for 1: C42H44Cd2C12N4O16, Mr = 1156.51, monoclinic, space group C2/c, a = 21.046(3), b = 11.0036(15), c = 20.012(3)A, β = 98.694(8)°, Z = 4, V = 4581.1(11) A3, Dc = 1.677 g/cm3, F(000) = 2280 and μ = 1.120 mm-1. Complex 1 possesses a thick and undulated two-dimensional layer with (6,3) topology, which interpenetrates with two others (above and below) to extend into a three-di- mensional supramolecular framework.

  1. Hydrothermal Synthesis and Crystal Structure of a Zinc Complex: [Zn2.5(phen)(BDC)2(OH)](phen = 1,10-Phenanthroline, BDC= Benzene-1,4-dicarboxylic Acid)

    Institute of Scientific and Technical Information of China (English)

    WANG Qing-Wei; LI Xiu-Mei; SHI Lin-Fang

    2008-01-01

    A metal-organic coordination polymer [Zn2.5(phen)(BDC)2(OH)]2 (phen = 1,10-phenanthroline, BDC = benzene-1,4-dicarboxylic acid)1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analyses and IR spectro-scopy. The complex crystallizes in the triclinic system, space group P1 with a = 11.199(2), b =11.593(2), c = 11.865(3) A, α= 99.330(1), β=111.506(1),γ = 104.804(1)°, V= 1328.4(5) A3, Dc=1.722 g/cm3, Z = 1, Mr = 1377.82, F(000) = 692, μ(MoKa) = 2.306 mm-1, S = 1.093, R = 0.0281 and wR= 0.0756 for 4179 observed reflections (Ⅰ 20(Ⅰ)). The coordination polyhedron around Zn(Ⅱ)can be described as a tetrahedron, trigonal bipyramid and octahedron. It is worth noting that the crystal structure of 1 is composed of tetranuclear zinc clusters linked by {ZnO6} units.

  2. 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.

  3. Coarse graining of polystyrene sulfonate

    Science.gov (United States)

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

    2015-03-01

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

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

    Science.gov (United States)

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

    2009-03-01

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

  5. 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.

  6. 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.

  7. Studies on Performance of Catalytic Esterification of Great Hole Sulfonic Acid-Lewis Acid Complex Resin%大孔磺酸-Lewis酸复合树脂催化酯化反应的研究

    Institute of Scientific and Technical Information of China (English)

    邢孔强; 刘煜

    2001-01-01

    The catalytic esterification of acetic anhydride and nine phenols were investigated in the presence of complex resin catalyst at 20 ℃,and its mechanismes were discussed. The results indicate that esterification had been outstanding progress under the catalyst of complex resin. The groups of benzene have some influence upon esterification of phenol.%研究了20 ℃时,醋酸酐与九种酚在复合树脂催化剂下的催化酯化反应,并探索了其反应的机理. 结果表明,复合树脂催化剂对反应有显著的催化作用,苯环上的各基团,对酚的酯化反应也有一定的影响.

  8. Enchansing the Ionic Purity of Hydrophilic Channels by Blending Fully Sulfonated Graft Copolymers with PVDF Homopolymer

    DEFF Research Database (Denmark)

    Nielsen, Mads Møller; Ching-Ching Yang, Ami; Jankova Atanasova, Katja;

    2013-01-01

    The influence of tuning the ionic content of membranes by blending, as opposed to varying the degree of sulfonation, is evaluated. Membranes of fully sulfonated poly(vinylidene fluoride-co-chlorotrifluoroethylene)-g-poly(styrene sulfonic acid) blended with PVDF were prepared and investigated...... for morphology, water sorption, and proton transport properties. The blend membranes exhibit conductivities superior to pure graft copolymers under fully humidified conditions despite their lower water uptake. Transmission electron microscopy images of the blends reveal that the membranes comprise a combination...

  9. Synthesis and characterization of quaternized poly(phthalazinone ether sulfone ketone) for anion-exchange membrane

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Chloromethylated poly(phthalazinone ether sulfone ketone) (CMPPESK) was prepared from poly(phthalazinone ether sulfone ketone) (PPESK) using chloromethyl octyl ethers (CMOE) with lower toxicity as chloromethylated regent. CMPPESK was soluble in N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMAc) and chloroform. Quatemized poly(phthalazinone ether sulfone ketone) (QAPPESK) was prepared from CMPPESK by quaternization. QAPPESK had excellent solvent resistance,which was only partly soluble in sulfuric acid (98%) and swollen in N,N-dimethylformamide (DMF). The vanadium redox flow battery (V-RFB) using QAPPESK anion-exchange membrane had better performance with 88.3% of overall energy efficiency.

  10. New core@shell nanogel based 2-acrylamido-2-methyl-1-propane sulfonic acid for preconcentration of Pb(II) from various water samples

    Science.gov (United States)

    Shoueir, Kamel Rizq; Akl, Magda Ali; Sarhan, Ali Ali; Atta, Ayman Mohamdy

    2016-12-01

    Poly(vinyl alcohol) core coated with poly(2-acrylamido-2-methyl-1-propanesulfonic acid-co-N-isopropylacrylamide) shell to produce well-define PVA@P(AMPS-co-NIPAm) core shell nanogels with a core of 25 ± 0.5 nm and shell of 5 ± 0.5 nm. The synthetic approach was produced by a surfactant free emulsion polymerization (SFEP). The specific area was found to be 1685.8 m2/g. The nanogels were studied in a batch adsorption for removal of Pb(II) ions and characterized by SEM, TEM, TGA and BET measurements. The results showed that the adsorption equilibrium data fitted the Langmuir isotherm and the kinetic studies are well described by the pseudo-second-order kinetic model. The Pb(II) maximum adsorption was 510.2 (mg/g) for PVA@P(90AMPS-co-10NIPAm) (wt.: wt%). The PVA@P(AMPS-co-NIPAm) nanogels were applied for extracting of Pb(II) in real different environmental water samples successfully with high recoveries reaches 104.4%.

  11. Determination of alachlor and its sulfonic acid metabolite in water by solid-phase extraction and enzyme-linked immunosorbent assay

    Science.gov (United States)

    Aga, D.S.; Thurman, E.M.; Pomes, M.L.

    1994-01-01

    Solid-phase extraction (SPE) and enzyme-linked immunosorbent assay (ELISA) were combined for the trace analysis of the herbicide alachlor and its major soil metabolite, ethanesulfonic acid (ESA). The anti-alachlor antibody cross-reacted with ESA, which produced false-positive detections of alachlor in water samples by immunoassay screens. Alachlor and ESA were isolated from water by SPE on a C18 resin and eluted sequentially with ethyl acetate and methanol. Alachlor is soluble in ethyl acetate while the anionic ESA is not. Thus ESA remained adsorbed on the C18 resin and was eluted later with methanol. The combination of SPE with ELISA effectivety separated and quantified both alachlor and ESA using the same antibody for two ELISA methods. The general method may have applicability for the separation of other herbicides and their ionic metabolites. The SPE-ELISA method has a, detection limit of 0.01 ??g/L for alachlor and 0.05 ??g/L for ESA, with a precision of ?? 10%. Analyses of surface and ground water samples were confirmed by gas chromatography/mass spectrometry and high-performance liquid chromatography with photodiode-array detection. Results showed widespread occurrence of ESA in surface and ground water of the midwestern United States, with concentrations ranging from 10 ??g/L.

  12. Alkylation reaction by propene of benzene on the high-temperature chlorination alumina catalyst; Koonensoshori arumina shokubaijo deno benzen no puropen nioru arukiruka hanno

    Energy Technology Data Exchange (ETDEWEB)

    Imanishi, Kazuhiro; Inui, Kanichiro; Honda, Kazuki; Shobu, Akinori

    1999-09-01

    Alkylation reaction by propene of benzene on alumina catalyst (AmLSA) chlorinated at 1073K was carried out using semibatch reactor (liquid phase catalytic reaction) and fixed bed flow reactor (vapor phase catalytic reaction) at atmospheric pressure 303K and 303-623K respectively. Products in liquid phase catalytic reaction were isopropyl benzene (IPB), diisopropyl benzene (di-IPB), triisopropyl benzene (tri-IPB), and the dissolution of the catalytic activity kind to the organic solvent was not observed. It was estimated, when propene was made to adsorb on Am LSA, because the generation of isopropylidene and 2 - propylene cation which coordinated in a strong Lewis acid point was observed, isopropyl reaction these cation benzene - complex. The generation of the high order substitute was promoted, when sodium was added to the catalyst, and the meta/para ratio of di-IPB increased. In vapor phase catalytic reaction, tetraisopropyl benzene (tetra-IPB) was also formed, and in the temperature of 473K or less, it was promoted further than the case in which the generation of tetra-IPB and di, tri was liquid phase catalytic reaction. IPB selectivity and selectivity of total replacement arthroplasty benzenes of consumed propene standard increased, when benzene/propene ratio in the raw material gas increased. In addition, at all reaction temperatures, the oligomerization of propene was generated, and the deactivation of the catalyst was caused. (translated by NEDO)

  13. 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.

  14. Determination of benzene in different food matrices by distillation and isotope dilution HS-GC/MS

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros Vinci, Raquel [Department of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent (Belgium); Canfyn, Michael [Food, Medicines and Consumer Safety, Scientific Institute of Public Health, Rue Juliette Wytsmanstraat 14, 1050 Brussels (Belgium); De Meulenaer, Bruno [Department of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent (Belgium); Schaetzen, Thibault de; Van Overmeire, Ilse; De Beer, Jacques [Food, Medicines and Consumer Safety, Scientific Institute of Public Health, Rue Juliette Wytsmanstraat 14, 1050 Brussels (Belgium); Van Loco, Joris, E-mail: Joris.VanLoco@iph.fgov.BE [Food, Medicines and Consumer Safety, Scientific Institute of Public Health, Rue Juliette Wytsmanstraat 14, 1050 Brussels (Belgium)

    2010-07-05

    Benzene is classified by the IARC as carcinogenic to humans. Several sources may contribute for the occurrence of benzene in foods, such as, environmental contamination and the reaction of benzoate salts with ascorbic acid (naturally present or added as food additives). Matrix effect on benzene recovery (e.g. in fatty foods) and artefactual benzene formation from benzoate during analysis in the presence of ascorbate are some of the challenges presented when determining benzene in a wide range of foodstuffs. Design of experiment (DOE) was used to determine the most important variables in benzene recovery from headspace GC/MS. Based on the results of the DOE, a versatile method for the extraction of benzene from all kind of food commodities was developed. The method which consisted of distillation and isotope dilution HS-GC/MS was in-house validated. Artefactual benzene was prevented by addition of a borate buffer solution (pH 11) under distillation conditions. The method presented in this study allows the use of a matrix-independent calibration with detection limits below the legal limit established by the European Council for benzene in drinking water (1 {mu}g L{sup -1}).

  15. Determination of benzene in different food matrices by distillation and isotope dilution HS-GC/MS.

    Science.gov (United States)

    Vinci, Raquel Medeiros; Canfyn, Michael; De Meulenaer, Bruno; de Schaetzen, Thibault; Van Overmeire, Ilse; De Beer, Jacques; Van Loco, Joris

    2010-07-01

    Benzene is classified by the IARC as carcinogenic to humans. Several sources may contribute for the occurrence of benzene in foods, such as, environmental contamination and the reaction of benzoate salts with ascorbic acid (naturally present or added as food additives). Matrix effect on benzene recovery (e.g. in fatty foods) and artefactual benzene formation from benzoate during analysis in the presence of ascorbate are some of the challenges presented when determining benzene in a wide range of foodstuffs. Design of experiment (DOE) was used to determine the most important variables in benzene recovery from headspace GC/MS. Based on the results of the DOE, a versatile method for the extraction of benzene from all kind of food commodities was developed. The method which consisted of distillation and isotope dilution HS-GC/MS was in-house validated. Artefactual benzene was prevented by addition of a borate buffer solution (pH 11) under distillation conditions. The method presented in this study allows the use of a matrix-independent calibration with detection limits below the legal limit established by the European Council for benzene in drinking water (1 microg L(-1)).

  16. Sulfonated polyimides containing triphenylphosphine oxide for proton exchange membranes

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-09-15

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

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

    Science.gov (United States)

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

    2007-12-13

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

  18. 新型砜基聚苯并咪唑的合成%Synthesis of Novel Sulfoned-polybenzimidazole

    Institute of Scientific and Technical Information of China (English)

    徐艺; 常冠军; 张林

    2012-01-01

    Adopted novel synthesis routine, a novel sulfoned-polybenzimidazole was synthesized in sulfolane from monomers of bifluoride and di(benzimidazolyl) benzenes which was prepared by the reaction of 4,4'-dicarboxyl-diphenylsulfone with o-phenylenediamine using polyphosphoric acid(PPA) as the catalysis. The structure was characterized by 'H NMR, IR, MS and elemental analysis.%采用新的合成路线,以多聚磷酸催化4,4′-二羧基二苯砜与邻苯二胺反应制得双苯并咪唑二苯砜(3);以3和4,4′-二氟二苯砜为单体,环丁砜为溶剂,在无水碳酸钾存在下合成了新型砜基聚苯并咪唑,其结构经1H NMR,IR,MS和元素分析表征.

  19. Single-step synthesis of sulfonated polyoxadiazoles and their use as proton conducting membranes

    Science.gov (United States)

    Gomes, Dominique; Roeder, Jerusa; Ponce, Mariela L.; Nunes, Suzana P.

    A single-step approach for the synthesis of sulfonated polyoxadiazoles from hydrazine sulfate was developed using non-sulfonated diacids in polyphosphoric acid. The post-sulfonation conditions were optimized by varying reaction time, medium and reagent concentrations in sulfuric acid, oleum and/or their mixtures. For the first time, a series of sulfonated polyoxadiazoles with ion exchange capacity (IEC) ranging from 1.26 to 2.7 meqiv. g -1 and high molecular weight (about 40,0000 g mol -1) were synthesized. The structures of the polymers were characterized by elemental analysis, 1H NMR, and FTIR. Sulfonated polyoxadiazole membranes with high thermal stability indicated by observed glass-transition temperatures (T g) ranging from 364 to 442 °C in sodium salt form and from 304 to 333 °C in acid form and with high mechanical properties (storage modulus about 3 GPa at 300 °C) have been prepared. The membrane stability to oxidation was investigated by soaking the film in Fenton's reagent at 80 °C for 1 h. The sulfonated polyoxadiazole membranes exhibited high oxidative stability, retaining 98-100% of their weight after the test. Proton conductivity values with the order of magnitude of 10 -1 to 10 -2 S cm -1 at 80 °C and with relative humidity ranging from 100% to 20% were obtained.

  20. 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.

  1. 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....

  2. Hydroxylation of Benzene to Phenol by H2O2 over an Inorganic-Organic Dual Modified Heteropolyacid☆

    Institute of Scientific and Technical Information of China (English)

    Li Jing; Fumin Zhang; Yijun Zhong; Weidong Zhu

    2014-01-01

    Various catalysts, including the heteropolyacid (HPA) H4PMo11VO40, its cesium salts, and inorganic–organic dual modified HPA catalyst, were prepared and characterized by Fourier transform infrared spectroscopy (FT-IR), nu-clear magnetic resonance (13C NMR), N2 adsorption, acid–base titration, electron spin resonance (ESR) and X-ray diffraction (XRD) techniques as wel as elemental analysis. These prepared catalysts were used in the hydroxyl-ation of benzene to phenol by H2O2 as oxidant. The inorganic–organic dual modified HPA Cs2.5(MIMPS)1.5 PMo11VO40, prepared by partially exchanging Cs+with protons in H4PMo11VO40 and followed by the immobili-zation of 3-(1-methylimidazolium-3-yl)propane-1-sulfonate (MIMPS), led to a liquid–solid biphasic catalysis system in the hydroxylation, which showed the best catalytic performance in terms of reusability and catalytic activity. The high reusability of Cs2.5(MIMPS)1.5PMo11VO40 in the heterogeneous hydroxylation was probably due to its high resistance in leaching of bulk HPA into the reaction medium. The slightly enhanced catalytic activ-ity for the catalyst was due to the acid sites available from MIMPS beneficial to the hydroxylation.

  3. 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.

  4. 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.

  5. 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.

  6. Benzaldehyde in cherry flavour as a precursor of benzene formation in beverages.

    Science.gov (United States)

    Loch, Christine; Reusch, Helmut; Ruge, Ingrid; Godelmann, Rolf; Pflaum, Tabea; Kuballa, Thomas; Schumacher, Sandra; Lachenmeier, Dirk W

    2016-09-01

    During sampling and analysis of alcohol-free beverages for food control purposes, a comparably high contamination of benzene (up to 4.6μg/L) has been detected in cherry-flavoured products, even when they were not preserved using benzoic acid (which is a known precursor of benzene formation). There has been some speculation in the literature that formation may occur from benzaldehyde, which is contained in natural and artificial cherry flavours. In this study, model experiments were able to confirm that benzaldehyde does indeed degrade to benzene under heating conditions, and especially in the presence of ascorbic acid. Analysis of a large collective of authentic beverages from the market (n=170) further confirmed that benzene content is significantly correlated to the presence of benzaldehyde (r=0.61, pbenzaldehyde in combination with ascorbic acid should be avoided.

  7. Acclimation of aerobic-activated sludge degrading benzene derivatives and co-metabolic degradation activities of trichloroethylene by benzene derivative-grown aerobic sludge.

    Science.gov (United States)

    Wang, Shizong; Yang, Qi; Bai, Zhiyong; Wang, Shidong; Wang, Yeyao; Nowak, Karolina M

    2015-01-01

    The acclimation of aerobic-activated sludge for degradation of benzene derivatives was investigated in batch experiments. Phenol, benzoic acid, toluene, aniline and chlorobenzene were concurrently added to five different bioreactors which contained the aerobic-activated sludge. After the acclimation process ended, the acclimated phenol-, benzoic acid-, toluene-, aniline- and chlorobenzene-grown aerobic-activated sludge were used to explore the co-metabolic degradation activities of trichloroethylene (TCE). Monod equation was employed to simulate the kinetics of co-metabolic degradation of TCE by benzene derivative-grown sludge. At the end of experiments, the mixed microbial communities grown under different conditions were identified. The results showed that the acclimation periods of microorganisms for different benzene derivatives varied. The maximum degradation rates of TCE for phenol-, benzoic acid-, toluene-, aniline- and chlorobenzene-grown aerobic sludge were 0.020, 0.017, 0.016, 0.0089 and 0.0047 mg g SS(-1) h(-1), respectively. The kinetic of TCE degradation in the absence of benzene derivative followed Monod equation well. Also, eight phyla were observed in the acclimated benzene derivative-grown aerobic sludge. Each of benzene derivative-grown aerobic sludge had different microbial community composition. This study can hopefully add new knowledge to the area of TCE co-metabolic by mixed microbial communities, and further the understanding on the function and applicability of aerobic-activated sludge.

  8. Electronic noses for monitoring benzene occupational exposure in biological samples of Egyptian workers

    Directory of Open Access Journals (Sweden)

    Ehab I. Mohamed

    2013-02-01

    Full Text Available Objectives: Benzene is commonly emitted in several industries, leading to widespread environmental and occupational exposure hazards. While less toxic solvents have been substituted for benzene, it is still a component of petroleum products and is a trace impurity in industrial products resulting in continued higher occupational exposures in industrial settings in developing countries. Materials and Methods: We investigated the potential use of an electronic nose (e-nose to monitor the headspace volatiles in biological samples from benzene-exposed Egyptian workers and non-exposed controls. The study population comprised 150 non-smoking male workers exposed to benzene and an equal number of matching non-exposed controls. We determined biomarkers of benzene used to estimate exposure and risk including: benzene in exhaled air and blood; and its urinary metabolites such as phenol and muconic acid using gas chromatography technique and a portable e-nose. Results: The average benzene concentration measured in the ambient air of the workplace of all studied industrial settings in Alexandria, Egypt; was 97.56±88.12 μg/m3 (range: 4.69–260.86 μg/m3. Levels of phenol and muconic acid were signifi cantly (p < 0.001 higher in both blood and urine of benzene-exposed workers as compared to non-exposed controls. Conclusions: The e-nose technology has successfully classifi ed and distinguished benzene-exposed workers from non-exposed controls for all measured samples of blood, urine and the exhaled air with a very high degree of precision. Thus, it will be a very useful tool for the low-cost mass screening and early detection of health hazards associated with the exposure to benzene in the industry.

  9. 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.

  10. Isotopic Measurements of Organic Sulfonates From The Murchison Meteorite

    Science.gov (United States)

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

    1995-01-01

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

  11. 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.

  12. Synthesis and characterization of polystyrene-poly(arylene ether sulfone)-polystyrene triblock copolymer for proton exchange membrane applications.

    Science.gov (United States)

    Yang, Jung-Eun; Hong, Young Talk; Lee, Jae-Suk

    2006-11-01

    The polystyrene-poly(arylene ether sulfone)-polystyrene (PS-PAES-PS) coil-semirod-coil triblock copolymer was synthesized by the condensation reaction of PS-COCI and H2N-PAES-NH2 telechelic polymers. The reaction was facile characterized by high yields with a perfect control over the block lengths. Following a known reaction protocol it was possible to selectively sulfonate the PS block of the triblock copolymer that led to the sulfonated copolymer sPS-PAES-sPS. Studies on its proton conductivity and methanol permeability were carried out to evaluate its use as the proton exchange membrane in direct methanol fuel cells. Proton conductivity of the membranes was increased depending on the sulfonic acid group content in the sulfonated polymer. The membranes exhibited good dimensional and thermal stability, and low methanol permeability compared to Nafion 117.

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

    Science.gov (United States)

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

    2011-09-01

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

  14. Preparation and Properties of Polypropylene Grafted Styrene Sulfonic Acid-polyaniline Antistatic Agents%聚丙烯接枝苯乙烯磺酸-聚苯胺抗静电剂的制备和性能

    Institute of Scientific and Technical Information of China (English)

    祖立武; 张晓宇; 王雅珍; 薛守成; 徐岽双; 张小舟

    2012-01-01

    以聚丙烯(PP)为基体, 以丙烯酸为掺杂剂, 采用溶液接枝法制备了聚丙烯接枝苯乙烯磺酸--聚苯胺(PP--g--SPS--PANI)高分子复合物, 用红外光谱仪、ZC--90数字高阻计和扫描电子显微镜等手段对高分子抗静电剂进行了表征。研究了引发剂用量、丙烯酸用量等因素对其抗静电性能的影响, 结果表明: 抗静电剂性能随着丙烯酸、引发剂用量增加先升高后降低, 丙烯酸掺杂使复合到PP分子链上聚苯胺分子链上的电荷离域形成共轭结构而具有导电性能, 当丙烯酸用量与聚丙烯接枝苯乙烯磺酸质量比m丙烯酸/ mPP-g-SPS=7:1, 引发剂与苯胺摩尔比nAPS/nANI=2:1时复合效率最高, 抗静电效果最好, 抗静电剂与PP共混物的电阻率下降到9.5×10^12Ω·cm。对PP共混物界面的SEM测试结果表明, 共混物具有良好的相容性。%Polymer complex of polypropylene grafted styrene sulfonic acid–polyaniline(PP–g–SPS–PANI) was prepared by solution grafting to acrylic acid as a dopant and polypropylene (PP) as the matrix. PP–g–SPS–PANI were characterized by fourier transfer infrared spectrometry(FTIR), ZC–90 digital impedance meter and scanning electron microscopy(SEM). The amount of acrylic and initiator to influence on antistatic properties were studied. The results showed that the antistatic properties of PP–g–SPS–PANI increased with the amount of the acrylic and initiator, and then decreased. Acrylic doped so that PANI molecular chain formed charge delocalized conjugated structure and having conductive properties. The complex efficient and antistatic properties of antistatic agents are best when the mass ratio of acrylic with polypropylene graft styrene sulfonamide acid(PP–g–SPS) macrylic/mPP?g?SPS=7:1, the molar ratio of initiator with aniline nAPS/nANI=2:1. The volume resistivity of PP–g–SPS–PANI/PP blends decreased to 9.5×1012Ω·cm. SEM results show that the

  15. Double photoionization of halogenated benzene

    Energy Technology Data Exchange (ETDEWEB)

    AlKhaldi, Mashaal Q. [Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstr. 36, D-10623 Berlin (Germany); Wehlitz, Ralf, E-mail: rwehlitz@gmail.com [Synchrotron Radiation Center, University of Wisconsin–Madison, Stoughton, Wisconsin 53589 (United States)

    2016-01-28

    We have experimentally investigated the double-photoionization process in C{sub 6}BrF{sub 5} using monochromatized synchrotron radiation. We compare our results with previously published data for partially deuterated benzene (C{sub 6}H{sub 3}D{sub 3}) over a wide range of photon energies from threshold to 270 eV. A broad resonance in the ratio of doubly to singly charged parent ions at about 65 eV appears shifted in energy compared to benzene data. This shift is due to the difference in the bond lengths in two molecules. A simple model can explain the shape of this resonance. At higher photon energies, we observe another broad resonance that can be explained as a second harmonic of the first resonance.

  16. Functionalization of benzene by superhalogens

    Science.gov (United States)

    Srivastava, Ambrish Kumar; Kumar, Abhishek; Misra, Neeraj

    2017-03-01

    We perform ab initio MP2/6-311++G(d,p) calculations to analyze the molecular properties and aromaticity of NO3, BO2 as well as BF4 superhalogen substituted benzene and compare them with well known electron withdrawing group substituted benzene such as C6H5F and C6H5CN in neutral and ionic forms. It has been noticed that the properties (including aromaticity) of C6H5BO2 closely resemble those of C6H5F and C6H5CN. On the contrary, C6H5NO3 possesses some quite different properties such as high electron affinity, small frontier orbital energy gap and enhanced aromaticity. It is also revealed that C6H5BF4 exists only in the form of C6H5F⋯BF3 complex.

  17. Detergency stability and particle characterization of phosphate-free spray dried detergent powders incorporated with palm C16 methyl ester sulfonate (C16MES).

    Science.gov (United States)

    Siwayanan, Parthiban; Aziz, Ramlan; Bakar, Nooh Abu; Ya, Hamdan; Jokiman, Ropien; Chelliapan, Shreeshivadasan

    2014-01-01

    Phosphate-free spray dried detergent powders (SDDP) comprising binary anionic surfactants of palm C16 methyl ester sulfonate (C16MES) and linear alkyl benzene sulfonic acid (LABSA) were produced using a 5 kg/h-capacity co-current pilot spray dryer (CSD). Six phosphate-free detergent (PFD) formulations comprising C16MES/LABSA in various ratios under pH 7-8 were studied. Three PFD formulations having C16MES/LABSA in respective ratios of 0:100 (control), 20:80 and 40:60 ratios were selected for further evaluation based on their optimum detergent slurry concentrations. The resulting SDDP from these formulations were analysed for its detergency stability (over nine months of storage period) and particle characteristics. C16MES/LABSA of 40:60 ratio was selected as the ideal PFD formulation since its resulting SDDP has consistent detergency stability (variation of 2.3% in detergency/active over nine months storage period), excellent bulk density (0.37 kg/L), fine particle size at 50% cumulative volume percentage (D50 of 60.48 μm), high coefficient of particle size uniformity (D60/D10 of 3.86) and large spread of equivalent particle diameters. In terms of surface morphology, the SDDP of the ideal formulation were found to have regular hollow particles with smooth spherical surfaces. Although SDDP of the ideal formulation have excellent characteristics, but in terms of flowability, these powders were classified as slightly less free flowing (Hausner ratio of 1.27 and Carr's index of 21.3).

  18. Crystal structures of the trifluoromethyl sulfonates M(SO3CF3)2 (M = Mg, Ca, Ba, Zn, Cu) from synchrotron X-ray powder diffraction data.

    Science.gov (United States)

    Dinnebier, Robert; Sofina, Natalia; Hildebrandt, Lars; Jansen, Martin

    2006-06-01

    The crystal structures of divalent metal salts of trifluoromethyl sulfonic acid ("trifluoromethyl sulfonates") M(SO(3)CF(3))(2) (M = Mg, Ca, Ba, Zn, Cu) were determined from high-resolution X-ray powder diffraction data. Magnesium, calcium and zinc trifluoromethyl sulfonate crystallize in the rhombohedral space group R(bar)3. Barium trifluoromethyl sulfonate crystallizes in the monoclinic space group I2/a(C2/c) and copper trifluoromethyl sulfonate crystallizes in the triclinic group P(bar)1. Within the crystal structures the trifluoromethyl sulfonate anions are arranged in double layers with the apolar CF(3) groups pointing towards each other. The cations are located next to the SO(3) groups. The symmetry relations between the different crystal structures have been analysed.

  19. Crystal Structures of the Trifluoromethyl Sulfonates M(SO3CF3)2 (M = Mg, Ca, Ba, Zn, Cu) from Synchrotron X-ray Powder Diffraction Data

    Energy Technology Data Exchange (ETDEWEB)

    Dinnebier,R.; Sofina, N.; Hildebrandt, L.; Jansen, M.

    2006-01-01

    The crystal structures of divalent metal salts of trifluoromethyl sulfonic acid ('trifluoromethyl sulfonates') M(SO{sub 3}CF{sub 3}){sub 2} (M = Mg, Ca, Ba, Zn, Cu) were determined from high-resolution X-ray powder diffraction data. Magnesium, calcium and zinc trifluoromethyl sulfonate crystallize in the rhombohedral space group R{bar 3}. Barium trifluoromethyl sulfonate crystallizes in the monoclinic space group I2/a(C2/c) and copper trifluoromethyl sulfonate crystallizes in the triclinic group P{bar 1}. Within the crystal structures the trifluoromethyl sulfonate anions are arranged in double layers with the apolar CF{sub 3} groups pointing towards each other. The cations are located next to the SO{sub 3} groups. The symmetry relations between the different crystal structures have been analyzed.

  20. One Step Preparation of Sulfonated Solid Catalyst and Its Effect in Esterification Reaction

    Institute of Scientific and Technical Information of China (English)

    康世民; 常杰; 范娟

    2014-01-01

    A carbon-based sulfonated catalyst was prepared by direct sulfonation and carbonization (in moderate conditions:200 °C, 12 h) of red liquor solids, a by-product of paper-making process. The prepared sulfonated cata-lyst (SC) had aromatic structure, composed of carbon enriched inner core, and oxygen-containing (SO3H, COOH, OH) groups enriched surface. The SO3H, COOH, OH groups amounted to 0.74 mmol·g-1, 0.78 mmol·g-1, 2.18 mmol·g-1, respectively. The fresh SC showed much higher catalytic activity than that of the traditional solid acid catalysts (strong-acid 732 cation exchange resin, hydrogen type zeolite socony mobile-five (HZSM-5), sulfated zir-conia) in esterification of oleic acid. SC was deactivated during the reactions, through the mechanisms of leaching of sulfonated species and formation of sulfonate esters. Two regeneration methods were developed, and the catalytic activity can be mostly regenerated by regeneration Method 1 and be fully regenerated by regeneration Method 2, respectively.

  1. Polymer electrolyte membranes from fluorinated polyisoprene-block-sulfonated polystyrene: Membrane structure and transport properties

    Energy Technology Data Exchange (ETDEWEB)

    Sodeye, Akinbode [Department of Polymer Science and Engineering, University of Massachusetts; Huang, Tianzi [University of Tennessee, Knoxville (UTK); Gido, Samuel [University of Massachusetts, Amherst; Mays, Jimmy [ORNL

    2011-01-01

    With a view to optimizing morphology and ultimately properties, membranes have been cast from relatively inexpensive block copolymer ionomers of fluorinated polyisoprene-block-sulfonated polystyrene (FISS) with various sulfonation levels, in both the acid form and the cesium neutralized form. The morphology of these membranes was characterized by transmission electron microscopy and ultra-small angle X-ray scattering, as well as water uptake, proton conductivity and methanol permeability within the temperature range from 20 to 60 C. Random phase separated morphologies were obtained for all samples except the cesium sample with 50 mol% sulfonation. The transport properties increased with increasing degree of sulfonation and temperature for all samples. The acid form samples absorbed more water than the cesium samples with a maximum swelling of 595% recorded at 60 C for the acid sample having 50 mol% sulfonation. Methanol permeability for the latter sample was more than an order of magnitude less than for Nafion 112 but so was the proton conductivity within the plane of the membrane at 20 C. Across the plane of the membrane this sample had half the conductivity of Nafion 112 at 60 C.

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

    Science.gov (United States)

    de Wolf, W; Feijtel, T

    1998-03-01

    A comparison of the estimated environmental concentration and the effect concentrations (in the laboratory or field) in the receiving compartment form the basis of environmental risk assessments. This paper reviews processes that critically influence the fate of LAS in the terrestrial environment. Concentrations of LAS in sludge are quite high due to sorption to primary sludge, precipitation of Ca and Mg-salts of LAS, and lack of biodegradation under anaerobic digestion. This implies that when sludge is applied to soil e.g. as a fertilizer, considerable amounts of this important surfactant may enter the terrestrial environment. Influence of aerobic situations on LAS concentrations during sludge storage needs further research to allow incorporation into the risk assessment. Aerobic biodegradation in soil is considered the most important removal mechanism of LAS loading to the terrestrial environment through sludge-amendment. Sorption plays a role in determining the residence time of a chemical in the soil, hereby enabling more time for biodegradation to occur. In addition, sorption may affect the expression of effects of surfactants towards benthic and soil dwelling organisms and plants. Another factor that needs further attention is the form of LAS in the environment, which is not similar to the commercial material applied in detergents. The differential sorption and biodegradation of the LAS components lead to a shift in the alkyl chain length (homologue), and phenylisomer distribution towards increased hydrophobicity. Also, occurrence of Ca/Mg-salts in the environment versus the Na-salt for the commercial material critically impacts the extrapolation of effects data obtained in lab studies (mostly performed with the commercial material) to the field. The literature data were used in combination with strategies and methods provided by the European Union Technical Guidance Document in support of risk assessment of new and notified substances (1996) for the prediction of environmental concentrations of LAS entering the soil system through sludge applications. Soil biodegradation is an essential, necessary element for the PEC-calculations of LAS. The initial realistic worst case assessment presented indicates no human health risks exists with indirect exposure to LAS through either food or drinking water. Also, current LAS use does not pose a risk to terrestrial organisms such as plants and invertebrates.

  3. Natural Biological Attenuation of Benzene in Groundwater

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Benzene has been found in subsurface unsaturated soil and groundwater beneath a petro-chemical plant. Although the groundwater contained several mg/L of benzene in the area immediately beneath the source, benzene was not detected in monitoring wells approximately 800m down stream. All kinds of physical processes such as adsorption and advection/dispersion are considered to account for the observed attenuation. The results indicated that the attenuation was primarily due to natural biological processes occurring within the aquifer. The evidence for the natural bioremediation of benzene from the groundwater included: (1) analysis of groundwater chemistry, (2) laboratory studies demonstrating benzene biodegradation in aquifer samples, and (3) computer simulations examining benzene transport. Laboratory experiments indicated that for conditions similar to those in the plume, the aerobic degradation of benzene by the naturally occurring microorganisms in the polluted groundwater samples was quite rapid with a half-life time of from 5 to 15 days. In situ analyses indicated the level of dissolved oxygen in the groundwater was over 2mg/L. Thus, oxygen should not limit the biodegradation. In fact, the benzene was also shown to degrade under anaerobic conditions. The results from the modeling simulations indicate that biodegradation is the dominant process influencing attenuation of the benzene.

  4. Carcinogenic effects of benzene: Cesare Maltoni's contributions.

    Science.gov (United States)

    Mehlman, Myron A

    2002-12-01

    Cesare Maltoni's contributions to understanding, identifying, and characterizing widely used commercial chemicals in experimental animals are among the most important methods developed in the history of toxicology and serve to protect working men and women, the general population, and our environment from hazardous substances. Maltoni developed experimental methods that have reached the "platinum standard" for protection of public health. Benzene was among the 400 or more chemicals that Maltoni and his associates tested for carcinogenicity. In 1976, Maltoni reported that benzene is a potent experimental carcinogen. Maltoni's experiments clearly demonstrated that benzene is carcinogenic in Sprague-Dawley rats, Wistar rats, Swiss mice, and RF/J mice when administered by inhalation or ingestion. Benzene caused carcinomas of the Zymbal gland, oral cavity, nasal cavities; cancers of the skin, forestomach, mammary glands, and lungs; angiosarcomas and hepatomas of the liver; and hemolymphoreticular cancers. Thus, benzene was shown to be a multipotential carcinogen that produced cancers in several species of animals by various routes of administration. On November 2, 1977, Chemical Week reported that Maltoni provided a "bombshell" when he demonstrated the "first direct link" between benzene and cancer. In this paper, I shall summarize early experiments and human studies and reports; Maltoni's experimental contribution to understanding the carcinogenicity of benzene in humans and animals; earlier knowledge concerning benzene toxicity; and benzene standards and permissible exposure levels.

  5. Production of Phenol from Benzene via Cumene

    Science.gov (United States)

    Daniels, D. J.; And Others

    1976-01-01

    Describes an undergraduate chemistry laboratory experiment involving the production of phenol from benzene with the intermediate production of isopropylbenzene and isopropylbenzene hydroperoxide. (SL)

  6. Highly charged proton-exchange membrane. Sulfonated poly(ether sulfone)-silica polyelectrolyte composite membranes for fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Shahi, Vinod K. [Electro-Membrane Processes Division, Central Salt and Marine Chemicals Research Institute, Bhavnagar-364002, Gujarat (India)

    2007-01-15

    Sulfonation of poly(ether sulfone) was carried out with chlorosulphonic acid in chloroform and its composite proton-exchange membrane was prepared using aminopropyltriethoxysilane as inorganic precursor by sol-gel in acidic medium. These membranes were further subjected to phosphorylation with phosphorous acid for introducing phosphonic acid functionality at inorganic segment. Extent of sulphonation was estimated by {sup 1}H-NMR spectroscopy while introduction of phosphonic acid groups was confirmed by FTIR spectroscopy and ion-exchange capacity studies. Different membranes, with varied silica content without and with phosphorylation, were characterized for their thermal and mechanical stabilities, physicochemical and electrochemical properties using thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), scanning electron microscopy (SEM), aq. methanol uptake studies, proton conductivity and methanol permeability measurements. The silica content in the membrane matrix and effect of phosphorylation was optimized as a function of membrane properties. Activation energy required for the proton transport across the membrane was also estimated and found to be comparable with Nafion 117 membrane. From the frictional interpretation and estimation of selectivity parameter it was observed that SPS-Si composite phosphorylated membrane with 20% silica content (SPS-Si(P)/20) resulted in the best proton-exchange membrane, which exhibited quite higher selectivity parameter in comparison to Nafion 117 for direct methanol fuel cell applications. Also, current-voltage polarization characteristics of SPS-Si(P)/20 membrane measured in direct methanol fuel cell, were found to be comparable to the Nafion 117 membrane. (author)

  7. 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.

  8. Influence of charge densities of randomly sulfonated polystyrene surfaces on cell attachment and proliferation.

    Science.gov (United States)

    Khatua, Dibyendu; Kwak, Byeongdo; Shin, Kwanwoo; Song, Ju-Myung; Kim, Joon-Seop; Choi, Jai-Hak

    2011-05-01

    Attachment and proliferation of NIH-3T3 fibroblast cells on random polymer surfaces, polystyrene sulfonated acid (PSSAx) with five different degrees of sulfonation (x = 0%, 5%, 10%, 15% and 33%) and on a tissue culture polystyrene (TCPS) surface were studied. The surface properties, wettability and roughness were measured by water-contact angle and atomic force microscopy measurement. The wettability and surface roughness increased with increasing the content of sulfonic acid groups on the surfaces. The number of cells attached on the surface after seeding increased with increasing x and reached to the maximum value on PSSA15. The cell proliferation also increased with increasing x. However, cell proliferation was slow down on PSSA33 in comparison to PSSA10 and PSSA15 surfaces after 48 h culture.

  9. Nanoscale Morphology of Sulfonated Polystyrene Ionomers

    Science.gov (United States)

    Zhou, Nancy C.; Winey, Karen I.

    2007-03-01

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

  10. Chemical of current interest--benzene.

    Science.gov (United States)

    Marcus, W L

    1987-03-01

    Benzene is one of the world's major commodity chemicals. It is derived from petroleum and coal and is used both as a solvent and as a starting material in chemical syntheses. The numerous industrial uses of benzene over the last century need not be recounted here, but the most recent addition to the list of uses of benzene is as a component in a mixture of aromatic compounds added to gasoline for the purpose of replacing lead compounds as anti-knock ingredients. The best known and longest recognized toxic effect of benzene is the depression of bone marrow function seen in occupationally exposed individuals. These people have been found to display anemia, leucopenia, and/or thrombocytopenia. When pancytopenia, i.e., the simultaneous depression of all three cell types, occurs and is accompanied by bone marrow necrosis, the syndrome is called aplastic anemia. In addition to observing this decrease in humans and relating it to benzene exposure, it has been possible to establish animal models which mimic the human disease. The result has been considerable scientific investigation into the mechanism of benzene toxicity. Although the association between benzene exposure and aplastic anemia has been recognized and accepted throughout most of this century, it is only recently that leukemia, particularly of the acute myelogenous type, has been related to benzene. The acceptance of benzene as an etiological agent in aplastic anemia in large measure derives from our ability to reproduce the disease in most animals treated with sufficiently high doses of benzene over the necessary time period. Unfortunately, despite extensive efforts in several laboratories, it has not been possible to establish a reproducible, reliable model for the study of benzene-induced leukemia. The recent demonstration that several animals exposed to benzene either by inhalation or in the drinking water during studies by Drs. B. Goldstein and C. Maltoni suggests that such a model may be forthcoming

  11. Anaerobic benzene oxidation by Geobacter species.

    Science.gov (United States)

    Zhang, Tian; Bain, Timothy S; Nevin, Kelly P; Barlett, Melissa A; Lovley, Derek R

    2012-12-01

    The abundance of Geobacter species in contaminated aquifers in which benzene is anaerobically degraded has led to the suggestion that some Geobacter species might be capable of anaerobic benzene degradation, but this has never been documented. A strain of Geobacter, designated strain Ben, was isolated from sediments from the Fe(III)-reducing zone of a petroleum-contaminated aquifer in which there was significant capacity for anaerobic benzene oxidation. Strain Ben grew in a medium with benzene as the sole electron donor and Fe(III) oxide as the sole electron acceptor. Furthermore, additional evaluation of Geobacter metallireducens demonstrated that it could also grow in benzene-Fe(III) medium. In both strain Ben and G. metallireducens the stoichiometry of benzene metabolism and Fe(III) reduction was consistent with the oxidation of benzene to carbon dioxide with Fe(III) serving as the sole electron acceptor. With benzene as the electron donor, and Fe(III) oxide (strain Ben) or Fe(III) citrate (G. metallireducens) as the electron acceptor, the cell yields of strain Ben and G. metallireducens were 3.2 × 10(9) and 8.4 × 10(9) cells/mmol of Fe(III) reduced, respectively. Strain Ben also oxidized benzene with anthraquinone-2,6-disulfonate (AQDS) as the sole electron acceptor with cell yields of 5.9 × 10(9) cells/mmol of AQDS reduced. Strain Ben serves as model organism for the study of anaerobic benzene metabolism in petroleum-contaminated aquifers, and G. metallireducens is the first anaerobic benzene-degrading organism that can be genetically manipulated.

  12. Mechanistic considerations in benzene physiological model development

    Energy Technology Data Exchange (ETDEWEB)

    Medinsky, M.A.; Kenyon, E.M.; Seaton, M.J.; Schlosser, P.M. [Chemical Industry Institute of Toxicology, Research Triangle Park, NC (United States)

    1996-12-01

    Benzene, an important industrial solvent, is also present in unleaded gasoline and cigarette smoke. The hematotoxic effects of benzene in humans are well documented and include aplastic anemia, pancytopenia, and acute myelogenous leukemia. However, the risks of leukemia at low exposure concentrations have not been established. A combination of metabolites (hydroquinone and phenol, for example) may be necessary to duplicate the hematotoxic effect of benzene, perhaps due in part to the synergistic effect of phenol on myeloperoxidase-mediated oxidation of hydroquinone to the reactive metabolite benzoquinone. Because benzene and its hydroxylated metabolites (phenol, hydroquinone, and catechol) are substrates for the same cytochrome P450 enzymes, competitive interactions among the metabolites are possible. In vivo data on metabolite formation by mice exposed to various benzene concentrations are consistent with competitive inhibition of phenol oxidation by benzene. In vitro studies of the metabolic oxidation of benzene, phenol, and hydroquinone are consistent with the mechanism of competitive interaction among the metabolites. The dosimetry of benzene and its metabolites in the target tissue, bone marrow, depends on the balance of activation processes such as enzymatic oxidation and deactivation processes such as conjugation and excretion. Phenol, the primary benzene metabolite, can undergo both oxidation and conjugation. Thus the potential exists for competition among various enzymes for phenol. Zonal localization of phase I and phase 11 enzymes in various regions of the liver acinus also impacts this competition. Biologically based dosimetry models that incorporate the important determinants of benzene flux, including interactions with other chemicals, will enable prediction of target tissue doses of benzene and metabolites at low exposure concentrations relevant for humans. 39 refs., 4 figs., 2 tabs.

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

    Science.gov (United States)

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

    2011-10-04

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

  14. Sorption behavior of rhodamine 6G onto sodium alginate graft poly (acrylic acid-co-2-acrylamido-2-methyl propane sulfonic acid)/kaolin composite hydrogel%SA-g-P(AA-co-AMPS)/KL对罗丹明6 G的吸附性能研究

    Institute of Scientific and Technical Information of China (English)

    朱林晖; 杨瑞; 张振涛; 丁马太; 杨静

    2014-01-01

    研究了海藻酸钠接枝聚丙烯酸2-丙烯酰胺-2-甲基丙磺酸/高岭土(SA-g-P (AA-co-AMPS)/KL)复合树脂对罗丹明6G 染液的吸附性能。探讨了染料初始浓度、吸附时间、pH 值对吸附性能的影响,并对吸附结果进行热力学和动力学拟合。结果表明,复合树脂对罗丹明6G 在实验条件下的最大吸附量为710 mg/g,吸附过程是自发的,且同时符合 Freudlich方程和 Redlich-Peterson 方程,动力学符合拟二级动力学方程。%Removal of rhodamine 6G from aqueous solutions using sodium alginate graft poly (acrylic acid-co-2-acrylamido-2-methyl-1-propane sulfonic acid )/kaolin composite hydrogel was sudied.The factors influencing the adsorption capacity such as initial concentrations of rhodamine 6G,contact time and pH values were discussed. Adsorption thermodynamics and kinetics were also investigated.Maximal adsorption capacity was 7 1 0 mg/g.It showed that the adsorption process was spontaneous and the adsorption isotherms were in good agreement with both Freudlich and Redlich-Peterson equations,the kinetics fit pseudo-second-order equation.

  15. 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.

  16. THE EFFECTS OF BENZENE BROMIDE MALONE COMBINED WITH INDAPAMIDE IN THE TREAT-MENT OF BLOOD PRESSURE AND URIC ACID%苯溴马隆与吲达帕胺联合治疗对血压和尿酸的影响

    Institute of Scientific and Technical Information of China (English)

    牛丽霞; 王虹; 李文静

    2015-01-01

    Objective To compare the different action on blood pressure and uric acid effects of the single hypertension treatment drug indapamide and the combination of benzene bromide malone and indapamide. Methods There were 350 patients in the clinical trial,who were divided randomly into two groups.175 patients were in the single drug indapamide treatment group,another 175 patients in the combination of benzene bromide malone and indapamide.The change of blood pressure,blood uric acid and urine uric acid of patients were detected.Results The value of blood uric acid and urine uric acid in the combination group of patients was significantly reduced compared to the single drug group.The amount of blood pressure re-turned to normal in the combination group was improved compared with them in the single drug group. Conclusions The combination of benzene bromide malone and indapamide for treating hypertension and hy-peruricemia is better than the single drug.%目的:比较单纯使用高血压治疗药物吲达帕胺与联合使用苯溴马隆和吲达帕胺对血压和尿酸的影响。方法随机将350例伴高尿酸血症的高血压患者分为二组,其中单纯使用吲达帕胺组175例,苯溴马隆与吲达帕胺联合使用组175例。观察二组患者血压、血尿酸和尿尿酸变化。结果联合用药组患者血尿酸值和尿尿酸值较单纯用药组相比,有显著性降低(P <0.05);联合用药组患者血压值恢复正常的人数与单纯用药组相比,有显著性提高(P <0.05)。结论苯溴马隆与吲达帕胺联合使用对改善高血压和高尿酸血症比单纯使用吲达帕胺疗效好。

  17. Properties of sulfonated cation-exchangers made from petroleum asphaltites

    Energy Technology Data Exchange (ETDEWEB)

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

    1982-01-10

    The use of ion-exchangers in radiochemical technology is accompanied by changes of their properties under the influence of ionizing radiation. The rate of development of these processes depends on the nature and structure of the matrix and on the nature and amount of ionic groups. We have proposed a method of synthesis of ion-exchangers resistant to ..gamma.. radiation from petroleum asphaltites. Continuing these investigations, we prepared cation-exchangers by sulfonation of a mixture of petroleum asphaltites and acid asphalt. An investigation of their radiation resistance is described in this paper.

  18. Voltammetric Determination of Acetaminophen in the Presence of Codeine and Ascorbic Acid at Layer-by-Layer MWCNT/Hydroquinone Sulfonic Acid-Overoxidized Polypyrrole Modified Glassy Carbon Electrode

    Directory of Open Access Journals (Sweden)

    Saeed Shahrokhian

    2011-01-01

    Full Text Available A very sensitive electrochemical sensor constructed of a glassy carbon electrode modified with a layer-by-layer MWCNT/doped-overoxidized polypyrrole (oppy/MWCNT /GCE was used for the determination of acetaminophen (AC in the presence of codeine and ascorbic acid (AA. In comparison to the bare glassy carbon electrode, a considerable shift in the peak potential together with an increase in the peak current was observed for AC on the surface of oppy/MWCNT/GCE, which can be related to the enlarged microscopic surface area of the electrode. The effect of the experimental conditions on the electrode response, such as types of counter ion, pyrrole and counter ion concentration, potential and number of cycles in the polymerization procedure, amount of MWCNT, and the pH, were investigated. Under the optimized conditions, the calibration curve was obtained over two concentration ranges of 2 × 10−7–6 × 10−6 M and 4 × 10−5–1 × 10−4 M of AC with a linear correlation coefficient (R2 of 0.9959 and 0.9947, respectively. The estimated detection limit (3σ for AC was obtained as 5 × 10−8 M. The developed method was successfully applied to analyze the pharmaceutical preparations of AC, and a recovery of 95% with a relative standard deviation of 0.98% was obtained for AC.

  19. Effect of repeated benzene inhalation exposures on benzene metabolism, binding to hemoglobin, and induction of micronuclei.

    Science.gov (United States)

    Sabourin, P J; Sun, J D; MacGregor, J T; Wehr, C M; Birnbaum, L S; Lucier, G; Henderson, R F

    1990-05-01

    Metabolism of benzene is thought to be necessary to produce the toxic effects, including carcinogenicity, associated with benzene exposure. To extrapolate from the results of rodent studies to potential health risks in man, one must know how benzene metabolism is affected by species, dose, dose rate, and repeated versus single exposures. The purpose of our studies was to determine the effect of repeated inhalation exposures on the metabolism of [14C]benzene by rodents. Benzene metabolism was assessed by characterizing and quantitating urinary metabolites, and by quantitating 14C bound to hemoglobin and micronuclei induction. F344/N rats and B6C3F1 mice were exposed, nose-only, to 600 ppm benzene or to air (control) for 6 hr/day, 5 days/week for 3 weeks. On the last day, both benzene-pretreated and control animals were exposed to 600 ppm, 14C-labeled benzene for 6 hr. Individual benzene metabolites in urine collected for 24 hr after the exposure were analyzed. There was a significant decrease in the respiratory rate of mice (but not rats) pretreated with benzene which resulted in lower levels of urinary [14C]benzene metabolites. The analyses indicated that the only effects of benzene pretreatment on the metabolite profile in rat or mouse urine were a slight shift from glucuronidation to sulfation in mice and a shift from sulfation to glucuronidation in rats. Benzene pretreatment also had no effect, in either species, on formation of [14C]benzene-derived hemoglobin adducts. Mice and rats had similar levels of hemoglobin adduct binding, despite the higher metabolism of benzene by mice. This indicates that hemoglobin adduct formation occurs with higher efficiency in rats. After 1 week of exposure to 600 ppm benzene, the frequency of micronucleated, polychromatic erythrocytes (PCEs) in mice was significantly increased. Exposure to the same level of benzene for an additional 2 weeks did not further increase the frequency of micronuclei in PCEs. These results indicate

  20. 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...

  1. Microwave Assisted Hydrolysis of Holocellulose Catalyzed with Sulfonated Char Derived from Lignin-Rich Residue

    Directory of Open Access Journals (Sweden)

    Kui Wang

    2015-01-01

    Full Text Available A microwave assisted green process has been developed for production of sugars through liquefying holocellulose catalyzed with sulfonated char derived from the lignin-rich residue produced during pretreatment of lignocellulose. Various reaction parameters including the hydrolysis temperature, hydrolysis time, catalyst content, and the ratio of water to feedstock were evaluated. The maximum sugars yield of 82.6% (based on the dry mass of holocellulose was obtained under the optimum reaction conditions. The sulfonated char showed superior catalytic performance to that of dilute sulfuric acid in converting holocellulose into sugars under microwave irradiation.

  2. Interphase cytogenetics of workers exposed to benzene

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, L.; Wang, Yunxia; Venkatesh, P. [Univ. of California, Berkeley, CA (United States)] [and others

    1996-12-01

    Fluorescence in situ hybridization (FISH) is a powerful new technique that allows numerical chromosome aberrations (aneuploidy) to be detected in interphase cells. In previous studies, FISH has been used to demonstrate that the benzene metabolites hydroquinone and 1,2,4-benzenetriol induce aneuploidy of chromosomes 7 and 9 in cultures of human cells. In the present study, we used an interphase FISH procedure to perform cytogenetic analyses on the blood cells of 43 workers exposed to benzene (median=31 ppm, 8-hr time-weighted average) and 44 matched controls from Shanghai, China. High benzene exposure (>31 ppm, n=22) increased the hyperdiploid frequency of chromosome 9 (p<0.01), but lower exposure (<31 ppm, n=21) did not. Trisomy 9 was the major form of benzene-induced hyperdiploidy. The level of hyperdiploidy in exposed workers correlated with their urinary phenol level (r= 0.58, p < 0.0001), a measure of internal benzene close. A significant correlation was also found between hyperdiploicly and decreased absolute lymphocyte count, an indicator of benzene hematotoxicity, in the exposed group (r=-0.44, p=0.003) but not in controls (r=-0.09, P=0.58). These results show that high benzene exposure induces aneuploidy of chromosome 9 in nondiseased individuals, with trisomy being the most prevalent form. They further highlight the usefulness of interphase cytogenetics and FISH for the rapid and sensitive detection of aneuploidy in exposed human populations. 35 refs., 3 figs., 2 tabs.

  3. Reduction of benzene toxicity by toluene.

    Science.gov (United States)

    Plappert, U; Barthel, E; Seidel, H J

    1994-01-01

    BDF1 mice were exposed in inhalation chambers to benzene (900 ppm, 300 ppm) and/or toluene (500 ppm, 250 ppm) 6 hr per day, 5 days per week, for up to 8 weeks. Benzene alone induced a slight anemia after 4 and 8 weeks and a reduction of BFU-E and CFU-E numbers in the marrow. The coexposure to toluene reduced the degree of anemia. These results confirm previous studies where toluene was found to reduce benzene toxicity. This protective effect was most pronounced when DNA damage was studied in peripheral blood cells, bone marrow, and liver using the single cell gel (SCG) assay. With benzene alone, either with 300 or 900 ppm, a significant increase in DNA damage was detected in cells sampled from all three organs. Toluene alone did not induce a significant increase in DNA damage. The coexposure of benzene and toluene reduced the extent of DNA damage to about 50% of benzene alone. This result is considered a clear indication for a protective effect of toluene on the genetic toxicity of benzene.

  4. Synthesis of porous sulfonated carbon as a potential adsorbent for phenol wastewater.

    Science.gov (United States)

    Prabhu, Azhagapillai; Al Shoaibi, Ahmed; Srinivasakannan, C

    2015-01-01

    The work reports a facile synthesis procedure for preparation of porous sulfonated carbons and its suitability for adsorption of phenol. The sulfonated carbon was synthesized utilizing a simplified, single-step, shorter duration process by sulfonation, dehydration and carbonization of sucrose in sulfuric acid and tetraethylorthosilicate. The surface and internal structures of the adsorbents were characterized utilizing various characterization techniques to understand the porous nature and surface functional groups of the porous matrix. Adsorption capacity was found to be highest for the sample heat treated at 600 °C, with the maximum adsorption capacity of 440 mg/g at 30 °C. The adsorption isotherms were tested with the Freundlich and Langmuir adsorption isotherms models to identify the appropriate adsorption mechanism.

  5. Excited state of protonated benzene and toluene

    Energy Technology Data Exchange (ETDEWEB)

    Esteves-López, Natalia; Dedonder-Lardeux, Claude; Jouvet, Christophe, E-mail: Christophe.jouvet@univ-amu.fr [Aix-Marseille Université, CNRS, UMR-7345, Physique des Interactions Ioniques et Moléculaires (PIIM), Marseille (France)

    2015-08-21

    We present photo-fragmentation electronic spectra of the simplest protonated aromatic molecules, protonated benzene and toluene, recorded under medium resolution conditions and compared with the photo-fragmentation spectrum of protonated pyridine. Despite the resolution and cold temperature achieved in the experiment, the electronic spectra of protonated benzene and toluene are structure-less, thus intrinsically broadened. This is in agreement with the large geometrical changes and the fast dynamic toward internal conversion predicted by ab initio calculations for protonated benzene [Rode et al., J. Phys. Chem. A 113, 5865–5873 (2009)].

  6. 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.

  7. 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.

  8. 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 tis