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Sample records for diglycidyl resorcinol ether

  1. 40 CFR 721.10017 - Amine terminated bisphenol A diglycidyl ether polymer (generic).

    Science.gov (United States)

    2010-07-01

    ... diglycidyl ether polymer (generic). 721.10017 Section 721.10017 Protection of Environment ENVIRONMENTAL... ether polymer (generic). (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substances identified generically as amine terminated bisphenol A diglycidyl ether polymer (PMNs P...

  2. 40 CFR 721.6980 - Dimer acids, polymer with polyalkylene glycol, bisphenol A-diglycidyl ether, and alky-lenepolyols...

    Science.gov (United States)

    2010-07-01

    ... reporting. (1) The chemical substance dimer acids, polymer with polyalkylene glycol, bisphenol A-diglycidyl... glycol, bisphenol A-diglycidyl ether, and alky-lenepolyols polyglycidyl ethers (generic name). 721.6980... Substances § 721.6980 Dimer acids, polymer with polyalkylene glycol, bisphenol A-diglycidyl ether, and alky...

  3. Reaction kinetics and modeling of photoinitiated cationic polymerization of an alicyclic based diglycidyl ether

    International Nuclear Information System (INIS)

    Harikrishna, R.; Ponrathnam, S.; Tambe, S.S.

    2014-01-01

    Highlights: • Photocationic polymerization of alicyclic based diglycidyl ether was carried out. • Kinetic parameters were influenced by gelation and diffusional restrictions. • Applicability of autocatalytic model was established by nonlinear regression. • System showed higher activation energy than cycloaliphatic and aromatic diepoxides. -- Abstract: Photoinitiated cationic polymerization of cycloaliphatic diepoxides had received tremendous attention, while studies with lesser polymerizable diglycidyl ethers are comparatively less reported. The present work deals with the photoinitiated cationic polymerization of cyclohexane dimethanol diglycidyl ether followed by estimation of kinetic parameters. The effects of concentration of photoinitiator and temperature on curing performance were studied using photo differential scanning calorimeter or photo DSC with polychromatic radiation. It was observed that the rate of polymerization as well as ultimate conversion increased with increasing concentration of photoinitiator and temperature. The influences of gelation as well as diffusional restrictions have remarkable effect on cure performance. The kinetic parameters as per autocatalytic kinetic model were studied by Levenberg–Marquardt nonlinear regression method instead of conventional linear method for obtaining more accurate values of apparent rate constant. It was observed that the model fits with data from initial stages to almost towards the end of the reaction. The activation energy was found to be higher than the values reported for more reactive cycloaliphatic diepoxides. The value of pre-exponential factor increased with increase in activation energy showing influence of gelation at early stages of reaction

  4. Analysis of reaction products of food contaminants and ingredients: Bisphenol A diglycidyl ether (BADGE) in canned foods

    NARCIS (Netherlands)

    Coulier, L.; Bradley, E.L.; Bas, R.C.; Verhoeckx, K.C.M.; Driffield, M.; Harmer, N.; Castle, L.

    2010-01-01

    Bisphenol A diglycidyl ether (BADGE) is an epoxide that is used as a starting substance in the manufacture of can coatings for food-contact applications. Following migration from the can coating into food, BADGE levels decay and new reaction products are formed by reaction with food ingredients. The

  5. Modified silyl-terminated polyether polymer blends with bisphenol A diglycidyl ether epoxy for adhesive applications

    International Nuclear Information System (INIS)

    Bitenieks, J; Meri, R Merijs; Zicans, J; Berzins, R; Umbraško, J; Rekners, U

    2016-01-01

    Modified silyl-terminated polyether polymer (MS Polymer) was blended with bisphenol A diglycidyl ether (DGEBPA) epoxy at MS Polymer/epoxy ratio from 30/70 to 70/30. MS Polymer/epoxy systems were examined for two-component adhesive formulation with additional fillers. Applicability of the MS Polymer/epoxy system at the ratio of the components 60/40 is demonstrated for the development of adhesive formulation. Rheological analysis of the components A and B shows suitable viscosity values for development of two- component adhesives formulation. Curing dynamics as well as tensile stress-strain properties and Shore A hardness of the chosen adhesive formulation are reasonable for the development of MS Polymer/epoxy type adhesive. (paper)

  6. Bisphenol diglycidyl ethers and bisphenol A and their hydrolysis in drinking water.

    Science.gov (United States)

    Lane, R F; Adams, C D; Randtke, S J; Carter, R E

    2015-04-01

    Epoxy coatings are commonly used to protect the interior (and exterior) surfaces of water mains and storage tanks and can be used on the interior surfaces of water pipes in homes, hospitals, hotels, and other buildings. Common major components of epoxies include bisphenols, such as bisphenol A (BPA) or bisphenol F (BPF), and their reactive prepolymers, bisphenol A diglycidyl ether (BADGE) and bisphenol F diglycidyl ether (BFDGE), respectively. There currently are health concerns about the safety of BPA and BPF due to known estrogenic effects. Determination of key bisphenol leachates, development of a hydrolysis model, and identification of stable hydrolysis products will aid in assessment of human bisphenol exposure through ingestion of drinking water. Liquid chromatography/mass spectrometry (LC/MS/MS) was used for quantitation of key analytes, and a pseudo-first order kinetic approach was used for modeling. In fill-and-dump studies on epoxy-coated pipe specimens, BADGE and a BPA-like compound were identified as leachates. The BADGE hydrolysis model predicts BADGE half-lives at pH 7 and 15, 25, 35, and 40 °C to be 11, 4.6, 2.0, and 1.4 days respectively; the BFDGE half-life was 5 days at pH 7 and 25 °C. The two identified BADGE hydrolysis products are BADGE-H2O and BADGE 2H2O, with BADGE 2H2O being the final end product under the conditions studied. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Fast liquid chromatography-tandem mass spectrometry for the analysis of bisphenol A-diglycidyl ether, bisphenol F-diglycidyl ether and their derivatives in canned food and beverages.

    Science.gov (United States)

    Gallart-Ayala, H; Moyano, E; Galceran, M T

    2011-03-25

    In this work a fast liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) method using a C18 Fused Core™ column, was developed for the simultaneous analysis of bisphenol A diglycidyl ether (BADGE), bisphenol A (2,3-dihydroxypropyl) glycidyl ether (BADGE·H(2)O), bisphenol A bis(2,3-dihydroxypropyl) ether (BADGE·2H(2)O), bisphenol A (3-chloro-2-hydroxypropyl) glycidyl ether (BADGE·HCl), bisphenol A bis(3-chloro-2-hydroxypropyl) ether (BADGE·2HCl) and bisphenol A (3-chloro-2-hydroxypropyl)(2,3-dihydroxypropyl ether) (BADGE·HCl·H(2)O) and bisphenol F diglycidyl ether (BFDGE), bisphenol F bis(2,3-dihydroxypropyl) ether (BFDGE·2H(2)O), bisphenol F bis(3-chloro-2-hydroxypropyl) ether (BFDGE·2HCl). The LC method was coupled with a triple quadrupole mass spectrometer, using an ESI source in positive mode and using the [M+NH(4)](+) adduct as precursor ion for tandem mass spectrometry experiments. The method developed was applied to the determination of these compounds in canned soft drinks and canned food. OASIS HLB solid phase extraction (SPE) cartridges were used for the analysis of soft drinks, while solid canned food was extracted with ethyl acetate. Method limits of quantitation ranged from 0.13 μgL(-1) to 1.6 μgL(-1) in soft drinks and 1.0 μgkg(-1) to 4.0 μgkg(-1) in food samples. BADGE·2H(2)O was detected in all the analyzed samples, while other BADGEs such as BADGE·H(2)O, BADGE·HCl·H(2)O, BADGE·HCl and BADGE·2HCl were also detected in canned foods. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Chlorination and chloramination of bisphenol A, bisphenol F, and bisphenol A diglycidyl ether in drinking water.

    Science.gov (United States)

    Lane, Rachael F; Adams, Craig D; Randtke, Stephen J; Carter, Ray E

    2015-08-01

    Bisphenol A (BPA), bisphenol F (BPF), and bisphenol A diglycidyl ether (BADGE) are common components of epoxy coatings used in food packaging and in drinking water distribution systems. Thus, leachates from the epoxy may be exposed to the disinfectants free chlorine (Cl2/HOCl/OCl(-)) and monochloramine (MCA, NH2Cl). Bisphenols are known endocrine disrupting chemicals (EDC) with estrogenic activity. Chlorination by-products have the potential to have reduced or enhanced estrogenic qualities, and are, therefore, of interest. In this work, chlorination reactions for bisphenols and BADGE were explored (via LC/MS/MS) and kinetic modeling (using a pseudo-first order approach) was conducted to predict the fate of these compounds in drinking water. The half-lives of BPA and BPF with 1 mg/L of free chlorine ranged from 3 to 35 min over the pH range from 6 to 11 and the temperature range of 10-25 °C. Half-lives for reactions of BPA and BPF with a nominal MCA concentration of 3.5 mg/L as Cl2 were from 1 to 10 days and were greater at higher pH and lower temperature. Formation of chlorinated bisphenol A by-products was observed during the kinetic studies. BADGE was found unreactive with either oxidant. Copyright © 2015. Published by Elsevier Ltd.

  9. A New Flexible Soy-Based Adhesive Enhanced with Neopentyl Glycol Diglycidyl Ether: Properties and Application

    Directory of Open Access Journals (Sweden)

    Jing Luo

    2016-09-01

    Full Text Available Soy-based adhesives inherently possess low water resistance and brittleness, which limit their application on plywood fabrication. This investigation involves using a long chain cross-linker, neopentyl glycol diglycidyl ether (NGDE, to produce an intrinsic toughening effect to reduce the brittleness and improve the water resistance of a soybean meal–based adhesive. The solids content, viscosity, functional groups, fracture surface micrographs, and thermal stability of the adhesives were measured. Three-layer plywood was fabricated using the resultant adhesive, and the tensile shear strength of the plywood was measured. All adhesive properties were compared with a soybean meal/polyamidoamine-epichlorohydrin (PAE adhesive and commercial melamine urea formaldehyde resin. The results showed that adding 6 g NGDE improved the water resistance of the soybean meal-based adhesive by 12.5%. This improvement is attributed to the following reasons: (1 a dense cross-linked network is formed by the chemical reaction between NGDE and protein molecules; (2 the toughness of the adhesive increases and a smooth and homogeneous fracture surface is created, which effectively prevents moisture intrusion; (3 the addition of NGDE increases the thermostability of the cured adhesive. The tensile shear strength of the plywood bonded with the soybean meal-based adhesive with 6 g NGDE was 286.2% higher than that without NGDE and attained 1.12 MPa, which was attributed to the reduction in the adhesive’s viscosity, and the improvement in the water resistance and toughness of the adhesive. The tensile shear strength of the plywood bonded with 6 g NGDE was 19.1% higher than that with 6 g PAE and was similar to the MUF resin, which validated the novel adhesive being suitable for use as an industrial plywood adhesive.

  10. Spectroscopic and molecular modeling approaches to investigate the interaction of bisphenol A, bisphenol F and their diglycidyl ethers with PPARα.

    Science.gov (United States)

    Zhang, Jie; Zhang, Tiehua; Guan, Tianzhu; Ruan, Ping; Ren, Dayong; Dai, Weichang; Yu, Hansong; Li, Tiezhu

    2017-08-01

    A fluorescence polarization (FP) assay for the simultaneous determination of bisphenol A (BPA), bisphenol F (BPF), bisphenol A diglycidyl ether (BADGE) and bisphenol F diglycidyl ether (BFDGE) was developed. The method was based on the competition between bisphenols (BPs) and fluorescein-labeled dexamethasone derivative (Dex-fl) for mouse peroxisome proliferator-activated receptor α ligand binding domain (mPPARα-LBD). A recombinant soluble protein derivative mPPARα-LBD* was prepared, then in vitro binding of 4 BPs to mPPARα-LBD* was investigated. Fluorescence polarization assay showed that these compounds exhibited different binding potencies with mPPARα-LBD*. Additionally, molecular dynamics simulations were performed to further understand the mechanism of BPs binding affinity for mPPARα-LBD*. Docking results elucidated that the driving forces for the binding of BPs to mPPARα-LBD* were predominantly dependent on hydrophobic and hydrogen-bonding interactions. Comparison of the calculated binding energies vs. experimental binding affinities yielded a good correlation (R 2  = 0.7258). The proposed method has potential for multi-residue detection of BPA, BPF, BADGE, and BFDGE. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Effects of Different Montmorillonite Nanoclay Loading on Cure Behavior and Properties of Diglycidyl Ether of Bisphenol A Epoxy

    Directory of Open Access Journals (Sweden)

    Alfred Tcherbi-Narteh

    2016-01-01

    Full Text Available The primary focus of this study was to understand the effects of different amounts of montmorillonite nanoclay (MMT loading on viscosity, cure behavior, reaction mechanism, and properties of diglycidyl ether of bisphenol A (DGEBA epoxy composites. Influence of 1–3 wt.% MMT on rheological and subsequent cure behavior of SC-15 epoxy resin was studied using nonisothermal and isothermal rheometry and differential scanning calorimetry (DSC. Rheological properties were influenced by different amounts of MMT at lower shear rates prior to and during curing. Cure reaction mechanism was unaffected by different MMT concentration; however heat and activation energy of reactions increased with increasing MMT loading. Samples with 2 wt.% MMT showed highest reaction rate constant, indicative of catalytic behavior. X-ray diffraction (XRD and transmission electron microscope (TEM revealed mainly intercalated microstructure throughout the MMT infused epoxy composite samples irrespective of the percent loading.

  12. Luminescence spectroscopy applied to a study of the curing process of diglycidyl-ether of bisphenol-A (DGEBA

    Directory of Open Access Journals (Sweden)

    Rita de Cássia Mendonça Sales

    2005-09-01

    Full Text Available This work involved the application of luminescence spectroscopy under steady-state conditions to study the curing process of the epoxy resin diglycidyl-ether of bisphenol-A (DGEBA using the curing agents 4,4'-diaminodiphenylmethane (DDM and 4,4'-diaminodiphenylsulfone (DDS. Two fluorescence methods were employed: the intrinsic method related to the polymeric matrix and the extrinsic method, using the molecular probe 9-anthroic acid (9-AA. Stoichiometric mixtures, with and without 9-AA, were heated to 120 °C at a 5 °C/min heating rate. These samples were then cured at 120 °C for a further 2 hours and allowed to cool to room temperature for 20 minutes. The results obtained by the two methods indicate that the cross-linking reaction can be monitored by analyzing the spectral changes of the emission bands of DGEBA, curing agents and 9-AA.

  13. Effects of Surface Treatments of Montmorillonite Nanoclay on Cure Behavior of Diglycidyl Ether of Bisphenol A Epoxy Resin

    International Nuclear Information System (INIS)

    Tcherbi-Narteh, A.; Hosur, M.V.; Triggs, E.; Jelaani, S.

    2013-01-01

    Diglycidyl ether of Bisphenol A (DGEBA) based SC-15 epoxy resin was modified with three different commercially available montmorillonite (MMT) nanoclay: Nanomer I.28E and Cloisite 10A and 30B. Cure behavior of nanocomposites was studied using a variety of techniques. Primary focus of this study was to investigate influence of different surface modifications of MMT nanoclay on rheological properties and cure behavior of SC-15 epoxy resin. By adding MMT to SC-15 epoxy resin, chemistry of the epoxy is altered leading to changes in rheological properties and ultimately enthalpy and activation energy of reactions. Addition of Nanomer I.28E delayed gelation, while Cloisite 10A and 30B accelerated gelation, regardless of the curing temperature. Activation energy of reaction was lower with the addition of Nanomer I.28E and Cloisite 10A and higher for Cloisite 30B compared to neat SC-15 epoxy composite.

  14. Analysis of reaction products of food contaminants and ingredients: bisphenol A diglycidyl ether (BADGE) in canned foods.

    Science.gov (United States)

    Coulier, Leon; Bradley, Emma L; Bas, Richard C; Verhoeckx, Kitty C M; Driffield, Malcolm; Harmer, Nick; Castle, Laurence

    2010-04-28

    Bisphenol A diglycidyl ether (BADGE) is an epoxide that is used as a starting substance in the manufacture of can coatings for food-contact applications. Following migration from the can coating into food, BADGE levels decay and new reaction products are formed by reaction with food ingredients. The significant decay of BADGE was demonstrated by liquid chromatographic (LC) analysis of foodstuffs, that is, tuna, apple puree, and beer, spiked with BADGE before processing and storage. Life-science inspired analytical approaches were successfully applied to study the reactions of BADGE with food ingredients, for example, amino acids and sugars. An improved mass balance of BADGE was achieved by selective detection of reaction products of BADGE with low molecular weight food components, using a successful combination of stable isotopes of BADGE and analysis by LC coupled to fluorescence detection (FLD) and high-resolution mass spectrometric (MS) detection. Furthermore, proteomics approaches showed that BADGE also reacts with peptides (from protein digests in model systems) and with proteins in foods. The predominant reaction center for amino acids, peptides, and proteins was cysteine.

  15. Quick and simple sample treatment for multiresidue analysis of bisphenols, bisphenol diglycidyl ethers and their derivatives in canned food prior to liquid chromatography and fluorescence detection.

    Science.gov (United States)

    Alabi, A; Caballero-Casero, N; Rubio, S

    2014-04-04

    We report herein a multiresidue method for canned food determination of 12 bisphenols [bisphenol A (BPA), bisphenol B (BPB), bisphenol F (BPF), bisphenol E (BPE)], bisphenol diglycidyl ethers [bisphenol F diglycidyl ether (BFDGE), bisphenol A diglycidyl ether (BADGE)] and their derivatives [BADGE·2H2O, BADGE·H2O, BADGE·HCl·H2O, BADGE·HCl, BADGE·2HCl and BFDGE·2HCl]. The method was based on the microextraction of the target contaminants in 200mg food sample with 600 μL of a supramolecular solvent made up of inverse aggregates of tetradecanol, followed by analysis of the extract by liquid chromatography/fluorescence detection using external calibration. Chromatographic separation of all target compounds, including the ortho-ortho, ortho-para and para-para isomers of BFDGE and BFDGE·2HCl, was achieved with baseline separation (Resolution ≥ 1.52). No concentration of the extracts was required, the microextraction took about 30 min and several samples could be simultaneous treated. Method validation was carried out according to the recommendations of the European Commission Decision 2002/657/EC. Quantitation limits for the different analytes ranged between 0.9 and 3.5 μg kg(-1). Repeatability and reproducibility, expressed as relative standard deviation, were in the ranges 1.8-6.8% and 4.4-8.1%. The method was applied to the analysis of the target compounds in different food categories including vegetables, legumes, fruits, fish and seafood, meat product and grain. Recoveries in samples were within the range 80-110%. Only BPF and BPE were undetected in the canned food analyzed. The concentration found for the rest of bisphenols, diglycidyl ethers and derivatives was in the range 7.1-959 μg kg(-1). The study of the isomeric distribution of BFDGE and BFDGE·2HCl in food showed that they are preferentially present as one of the isomeric forms, that highlighting for further studies. The analytical and operational characteristics of this multiresidue method make

  16. Concentrations of bisphenol a, bisphenol a diglycidyl ether, and their derivatives in canned foods in Japanese markets.

    Science.gov (United States)

    Yonekubo, Jun; Hayakawa, Kazuichi; Sajiki, Junko

    2008-03-26

    Bisphenol A (BPA), bisphenol A diglycidyl ether (BADGE), and their derivatives in 38 canned foods sold in Japan were measured using high-performance liquid chromatography-mass spectrometry (LC-MS) and LC-tandem mass spectrometry (LC-MS/MS). BPA, BADGE, BADGE.2H 2O, BADGE.HCl.H2O, BADGE.HCl, and BADGE.2HCl were 0-235.4, 0-3.4, 0-247.2, 0.2-196.4, 0-3.0, and 0-25.7 ng/g, respectively, which did not exceed acceptable daily intake for BPA and specific migration limit for BADGEs. BADGE was degraded by 58, 100, 46, and 58% in water (pH 7), 0.01 N HCl (pH 2), 0.01 N NaCl (pH 6.8), and 0.01 N NaCl with acetic acid (pH 2.5), respectively, when it was allowed to stand at 120 degrees C for 30 min. The prominent derivatives formed were BADGE.2H 2O and BADGE.HCl.H2O, which was formed not only in BADGE with added HCl but also in that with NaCl. Acetic acid accelerated the formation of both BADGE.2H2O and BADGE.HCl.H2O in NaCl. No BPA was detected in any simulation samples started from BADGE. The results suggest that BPA and BADGE are independently leached into canned foods and that BADGE is easily changed to more stable compounds such as BADGE.2H2O and BADGE.HCl.H2O by sterilization.

  17. Unexpected differences between thermal and photoinitiated cationic curing of a diglycidyl ether of bisphenol A modified with a multiarm star poly(styrene-b-poly(ε-caprolactone polymer

    Directory of Open Access Journals (Sweden)

    J. M. Morancho

    2013-07-01

    Full Text Available The effect of adding a multiarm star poly(styrene-b-poly(ε-caprolactone polymer on the cationic thermal and photoinitiated curing of diglycidyl ether of bisphenol A was studied. This star-polymer decelerated the thermal curing of diglycidyl ether of bisphenol A and modified the final structure of the epoxy matrix. The photocuring was influenced significantly by the addition of the multiarm star. When the proportion of this modifier added was 5%, much more time was necessary for complete photocuring (160 min at 40ºC. In the presence of 10% of modifier, the degree of photocuring reached was very low (0.196 at 120°C. A subsequent thermal post-curing was necessary to cure completely the system. During photocuring in presence of poly(styrene-b-poly(ε-caprolactone, the formation of dormant species, which are reactivated when the temperature increases, takes places. The kinetics of the thermal curing and the photocuring was analyzed using an isoconversional method due to the complexity of the reactive process. Applying this method, it has been confirmed the dependence of activation energy on the degree of conversion. The fracture morphology analyzed by scanning electron microscopy exhibited a second phase originated during photocuring by the presence of the modifier.

  18. 40 CFR 721.7260 - Polymer of poly-ethylene-polyamine and alkanediol di-gly-cidyl ether.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polymer of poly-ethylene-polyamine and... New Uses for Specific Chemical Substances § 721.7260 Polymer of poly-ethylene-polyamine and alkanediol... chemical substance identified generically as polymer of polyethylenepolyamine and alkanediol diglycidyl...

  19. Matrix effect on leaching of Bisphenol A diglycidyl ether (BADGE) from epoxy resin based inner lacquer of aluminium tubes into semi-solid dosage forms.

    Science.gov (United States)

    Lipke, Uwe; Haverkamp, Jan Boris; Zapf, Thomas; Lipperheide, Cornelia

    2016-04-01

    To study the impact of different semi-solid dosage form components on the leaching of Bisphenol A (BPA) and Bisphenol A diglycidyl ether (BADGE) from the epoxy resin-based inner lacquer of aluminium tubes, the tubes were filled with different matrix preparations and stored at an elevated temperature. Despite compliance with the European Standards EN 15348 and EN 15766 on porosity and polymerisation of internal coatings of aluminium tubes, the commercially available tubes used in the study contained an increased amount of polymerisation residues, such as unbound BPA, BADGE and BADGE derivatives in the lacquer, as determined by acetonitrile extraction. Storage of Macrogol ointments in these tubes resulted in an almost quantitative migration of the unbound polymerisation residues from the coating into the ointment. In addition, due to alterations observed in the RP-HPLC chromatograms of the matrix spiked with BADGE and BADGE derivatives it is supposed that the leachates can react with formulation components. The contamination of the medicinal product by BPA, BADGE and BADGE derivatives can be precluded by using aluminium tubes with an internal lacquer with a low degree of unbound polymerisation residues. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  20. Caracterização do sistema éter diglicidílico do bisfenol A / poliaminas alifáticas Characterization of diglycidyl ether of bisphenol A / aliphatic polyamines systems

    Directory of Open Access Journals (Sweden)

    Filiberto González-Garcia

    2005-11-01

    Full Text Available O sistema epoxídico constituído pelo éter diglicidílico do bisfenol A (DGEBA, produto DER 331 com endurecedor 24 comercializados pela Dow Química do Brasil foi caracterizado por métodos espectroscópicos, calorimétricos e de determinação de grupos funcionais. O endurecedor 24 é constituído por trietilenotetramina (60 % molar e uma mistura de etilenoaminas polifuncionais com estruturas lineares, ramificadas e cíclicas. O equivalente epoxídico da resina resultou de 187 g eq-1. A funcionalidade média, o equivalente de amina, e a concentração do endurecedor que satisfaz a estequiometria, corresponde a 5,54, 27,5 g eq-1, e 14,7 phr, respectivamente. O sistema epoxídico manifestou uma entalpia de reação de 486 J g-1 (106,6 kJ eq-1, e uma temperatura de transição vítrea (Tg¥ de 124 ºC. O trabalho apresenta ainda um programa de cura em duas etapas onde se alcança a conversão máxima, e se apresenta o diagrama de transformações conversão vs temperatura (CTT.Diglycidyl ether of the bisphenol A (DGEBA, product DER 331 and hardener 24 system marketed by Chemical Dow of Brazil were characterized by spectroscopic, calorimetric and determination of functional groups methods. The hardener 24 is constituted by triethylenetetramine (60 % molar and a mixture of ethylene polyfunctional amines with linear, ramified and cyclic structures. The epoxy equivalent of the resin corresponds to 187 g eq-1. The functionality average, equivalent amine, and the concentration of the hardener that satisfy the stoichiometry corresponds to 5.54, 27.5 g eq-1, and 14.7 phr, respectively. The epoxy system displayed an enthalpy of reaction of 486 J g-1 (106.6 kJ eq-1, and a glass transition temperature (Tg¥ of 124 ºC. Also presented in this work is a cure program in two stages where the maximum conversion was reached.

  1. Resorcinol derivatives from Ardisia maculosa.

    Science.gov (United States)

    Zheng, Ying; Wu, Feng-E

    2007-01-01

    Besides a series of known sterols and triterpenoids, a new resorcinol (1) and a known resorcinol (2) have been isolated from ethanol extract of Ardisia maculosa for the first time. The structures of these resorcinol derivatives were elucidated as 2-methyl-5-(Z-heptadec-8-enyl) resorcinol and 5-Z-heptadec-8-enyl) resorcinol by HRESI-MS, NMR ((1)H, (13)C, HSQC, HMBC) experiments. In our in vitro assay, compounds 1 and 2 showed no antimicrobial activities, however, compound 2 exhibited cytotoxity activity against human cancer cell line with GI(50) value of 2.14 x 10(- 4) mmol/ml.

  2. Separação de fases induzida por meio de reação química no sistema éter diglicidílico do bisfenol A e piperidina com poli(metacrilato de metila Phase separation induced by chemical reaction in the system of diglycidyl ether of bisphenol A and piperidine with poly(methyl methacrylate

    Directory of Open Access Journals (Sweden)

    Filiberto González Garcia

    2003-12-01

    Full Text Available O comportamento da separação de fases e da gelificação do sistema epoxídico, constituído pelo éter diglicidílico do bisfenol A (DGEBA e a piperidina, modificado com poli(metacrilato de metila (PMMA, foi estudado na faixa de temperatura de 60 °C - 120 °C. A concentração de PMMA e a temperatura de cura causam mudanças significativas na morfologia gerada. A massa molecular de PMMA provoca ligeiras mudanças para a observação da separação de fases e não afeta a velocidade da reação. O sistema modificado com PMMA mostra o efeito de retardação cinético e a velocidade de separação de fases é maior que a velocidade de polimerização.The phase separation and gelification behavior of epoxy system based on diglycidyl ether of bisphenol-A (DGEBA and piperidine modified with poly(methyl methacrylate (PMMA were studied in the range between 60 °C and 120 °C. The morphology is influenced by the PMMA content in the blend and also by the cure temperature. The molecular weight of PMMA provokes slight changes on cloud point and does not affect the reaction rate. The systems modified by PMMA exhibited kinetic retardation effect but the cloud point rate was higher than the polymerization rate.

  3. Determination of bisphenol a diglycidyl ether content in foods from ...

    African Journals Online (AJOL)

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  4. Crosslinking in the diglycidyl ether oligoepichlorhydrin-piperazine

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    Konstantyn E. Varlan

    2014-03-01

    Full Text Available The possibility of acquiring film material from a mixture of oligoepichlorhydrin diglycidylether and piperazyne discussed. The process involves elongation of the chain by means of reaction of the oligomer terminal oxyran cycles with piperazine aminogrups, and the subsequent formation of crosslinked by tertiary amine alongthe chainsalkylation whis chlorometyl dand groups of macromolecules. With this purpose, the model system investigated: epichlorohydrin−piperidine, epichlorohydrin−piperazine, oligoetylenglikol glicidyl ether−piperazine. The possibility of regulating the contributions of reactions of epoxy group and alkylation on crosslinking primary stage is disclosed, as well as material properties. Taking into account the found regularities receive elastic film structured materials with quaternary nitrogen atoms in the nodes. The ratio of tertiary and quaternary structure of nitrogen depends on the process conditions. Films swell in polar solvents and has ion-exchange properties.

  5. Biodegradation of resorcinol byPseudomonas sp.

    Institute of Scientific and Technical Information of China (English)

    Nader Hajizadeh; Najibeh Shirzad; Ali Farzi; Mojtaba Salouti; Azra Momeni

    2016-01-01

    ABSTRACT Objective:To investigate the ability ofPseudomonas sp. isolated from East Azarbaijan, Iran in bioremediation of resorcinol. Methods: Resorcinol biodegradation was evaluated using spectrophotometry and confirmed by gas chromatography-mass spectroscopy. Results:This isolate was able to remove up to 37.12% of resorcinol from contaminated water. Reusability experiments had confirmed the biodegradation process which produced seven intermediate compounds. These intermediates were characterized by gas chromatography-mass spectroscopy technique. The products of resorcinol biodegradation were apparently 1, 4-cyclohexadiene, nonadecene, 2-heptadecanone, 1-isopropyl-2-methoxy-4-methylbenzene, hexadecanoic acid, 9-octadecenoic acid, phenol and 5-methyl-2-(1-methylethyl). Conclusions: The findings revealed thatPseudomonas sp. is able to degrade resorcinol. Because of being an indigenous organism, this isolate is more compatible with the climate of the northwest region of Iran and possibly will be used for degradation of other similar aromatic compounds.

  6. Solid-state /sup 13/C NMR study of cured resorcinol-formaldehyde resins

    Energy Technology Data Exchange (ETDEWEB)

    Lippmaa, H.; Samoson, A.

    1988-08-01

    The curing process generally follows the pattern observed in the stage of prepolymer formation. Catalysts (NaOH, hexa, Mg(OCOCH/sub 3/)/sub 2/) that have no substantial influence on the isomeric composition of the resorcinol-formaldehyde prepolymers, do not affect the isomeric composition of the cured resins to any significant extent either. Isomeric composition of the cured resins depends mostly on the presence of water during the curing process, necessary for depolymerisation of the added paraformaldehyde. Curing in the melt leads to enhanced 2-substitution in the 1,3-dihydroxybenzene rings. In the /sup 13/C NMR spectra of cured powdered samples, the tendency of 5-methylresorcinol to form oligomers with a higher degree of 2-substitution than resorcinol is clearly apparent. Polycondensation process continues in the powdered resins after initial curing until complete consumption of all formaldehyde. Curing of phenol-formaldehyde resols proceeds through intermediate dimethylene ether formation.

  7. Dust Measurement of Two Organophosphorus Flame Retardants, Resorcinol Bis(diphenylphosphate) (RBDPP) and Bisphenol A Bis(diphenylphosphate) (BPA-BDPP), Used as Alternatives for BDE-209

    NARCIS (Netherlands)

    Brandsma, S.H.; Sellström, U.; de Wit, C.A.; de Boer, J.; Leonards, P.E.G.

    2013-01-01

    Resorcinol bis(diphenylphosphate) (RBDPP) and bisphenol A bis(diphenylphosphate) (BPA-BDPP) are two halogen-free organophosphorus flame retardant (PFRs) that are used as an alternative for the decabromodiphenyl ether (Deca-BDE) technical mixture in TV/flatscreen housing and other electronic consumer

  8. (2-PYRIDYLAZO)RESORCINOL FOR FLOTATION

    African Journals Online (AJOL)

    KEY WORDS: Iron(II), Fe-PAR complex, Flotation, Spectrophotometry, Soils, Zinc sulfide concentrates. INTRODUCTION. 4-(2-Pyridylazo)resorcinol (PAR) is one of the most popular analytical reagents. It forms colored complexes with many metal ions and can be used for their spectrophotometric determination. A well-known ...

  9. Modificação de polímeros termorrígidos por separação de fases induzida por reação química: Sistema éter diglicidílico do Bisfenol-A e trietilenotetramina com copolímeros acrílicos Modification of thermosetting polymers by induced phase separation by chemical reaction: Diglycidyl ether of Bisphenol-A and triethylenetetramine with acrylic copolymers

    Directory of Open Access Journals (Sweden)

    Garcia Filiberto González

    2008-03-01

    Full Text Available O comportamento da separação de fases e da gelificação do sistema do éter diglicidílico do Bisfenol-A com trietilenotetramina modificado com diferentes copolímeros acrílicos foi estudado. As massas moleculares e as concentrações de grupos carboxílicos nos copolímeros provocaram mudanças significativas na morfologia e provocaram ligeiras mudanças para a observação da separação de fases. Contudo, não mudaram de maneira significativa os tempos de gelificação e não afetaram a velocidade da reação. O sistema modificado com os copolímeros acrílicos mostrou o efeito de retardação cinética. A morfologia foi relacionada com a aderência ao cisalhamento, em juntas de aço-aço, através de ensaios de resistência mecânica usando juntas de cisalhamento simples, as que foram produzidas com o sistema modificado com os copolímeros acrílicos segundo a norma ASTM D 1002. Amostras com a fase dispersa apresentando morfologia com partículas de diâmetro médio menor que 0,10 µm mostraram o melhor desempenho de aderência ao cisalhamento para as massas moleculares dos copolímeros estudadas. Entretanto, um melhor comportamento mecânico para as concentrações de grupos carboxílicos nos copolímeros acrílicos foi observado para a morfologia com distribuição de tamanhos de partículas na faixa de 0,20 a 0,52 µm.The cloud point and the gel time behavior of an epoxy system based on diglycidyl ether of Bisphenol-A with triethylenetetramine modified with different acrylic copolymers were studied. The molecular weights and the concentration of carboxyl groups in the copolymers affected the morphology and the cloud point, but did not affect the gel times and reaction rates significantly. The system modified with the acrylic copolymers exhibited kinetic retardation effects. The morphology was related to adherence to the lap shear in steel-steel joints, through mechanical resistance essays using a single-lap-joint, which was produced

  10. Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market.

    Science.gov (United States)

    Uematsu, Y; Hirata, K; Suzuki, K; Iida, K; Saito, K

    2001-02-01

    BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GC-MS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1 mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl anti BFDGE.HCl.H2O at a level of 1.5 mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.

  11. Environmental and occupational exposure to resorcinol in Finland.

    Science.gov (United States)

    Porras, Simo P; Hartonen, Minna; Ylinen, Katriina; Tornaeus, Jarkko; Tuomi, Tapani; Santonen, Tiina

    2018-03-27

    Resorcinol is a suspected endocrine disruptor that affects thyroid function by inhibiting thyroxin peroxidase. It may also have an impact on iodine uptake. Resorcinol has various uses; for example in the manufacture of rubber products and in wood adhesives, flame retardants, UV stabilizers, and dyes. It is also used in personal care products such as hair colorants, anti-acne preparations, and peels. The aim of this study was to assess both environmental background exposure and occupational exposure to resorcinol in Finland. We investigated occupational exposure in hairdresser work and in the manufacture of tyres, adhesive resins and glue-laminated timber by biomonitoring total resorcinol concentration in urine samples. The biomonitoring results were compared to the urinary levels of occupationally non-exposed volunteers, and to the biomonitoring equivalent (BE), which we estimated on the basis of the EFSA's acceptable daily intake (ADI) value for resorcinol. Almost all the urine samples (99%) of the non-occupationally exposed volunteers contained measurable amounts of resorcinol. The urinary resorcinol data were rather scattered, and the resorcinol concentrations among women (GM 84 μg/l, 95th percentile 2072 μg/l) were clearly higher than the respective concentrations among men (GM 35 μg/l, 95th percentile 587 μg/l). The reason for this difference remains unclear. Although the two highest results exceeded the BE of 4 mg/l calculated on the basis of the EFSA's ADI, the 95th percentile of the occupationally non-exposed volunteers' results remained well below the BE among both males and females. According to the results, hairdressers' exposure to resorcinol was at the same level as that of the reference population of occupationally non-exposed volunteers. All hairdresser's values remained below the BE for resorcinol. The urinary resorcinol levels of the industrial workers were also at the same level as those of the reference population. We observed

  12. Survey of the occurrence of 1,6-hexanediol diglycidyl ether in food contact materials

    DEFF Research Database (Denmark)

    producers and importers. The substance is not allowed for use in plastic materials for food contact. One Danish company reported a possible use of HDDGE in coating of drinking tanks and pipelines. This is the only use of HDDGE confirmed in relation to food contact materials in Denmark. The project...... is following up on a previous survey under the Danish EPA’s LOUS-review (Environmental Project no. 1472)....

  13. Boron complexing with H-resorcinol and acidic hydroxyxanthene dyes

    International Nuclear Information System (INIS)

    Nazarenko, V.A.; Flyantikova, G.V.; Chekirda, T.N.

    1984-01-01

    Complex formation of boron with H-resorcinol (hr; 2,4-dihydroxybenzene-azo -8-hydroxynaphtalene-3,6-disulfonic acid) and acidic hydroxyxanthene dyes (hxd: fluorescein, eosine, erathrosine). Mixed-ligand complexes with a ratio of r:hr:hxd=1:1:1 are formed at pH=5-6. The chemism of the complex formation of boron with H-resorcinol and fluorescein has been studied. The stability consta nt of the complex is 1.12x10 21 , the conditional molar absorptivitis 1.80x10 0 . This complex formation reaction was used for photometric determination of boron in natural water

  14. Characteristics of the wood adhesion bonding mechanism using hydroxymethyl resorcinol

    Science.gov (United States)

    Douglas J. Gardner; Charles E. Frazier; Alfred W. Christiansen

    2006-01-01

    A recent collaborative effort among the U.S. Forest Products Laboratory, Virginia Tech, and the University of Maine has explored the possible bonding mechanisms contributing to durable wood adhesive bonding using hydroxymethyl resorcinol (HMR) surface treatment. Current adhesive bonding mechanisms include: mechanical interlocking, electronic or electrostatic theory,...

  15. Concise access to primin, miconidin and related natural resorcinols

    Czech Academy of Sciences Publication Activity Database

    Šíša, Miroslav; Dvořáková, Marcela; Vaněk, Tomáš

    2017-01-01

    Roč. 73, č. 35 (2017), s. 5297-5301 ISSN 0040-4020 R&D Projects: GA MŠk(CZ) LD15006 Institutional support: RVO:61389030 Keywords : Cross - coupling * Natural products * Primin * Qionones * Resorcinols Subject RIV: CC - Organic Chemistry OBOR OECD: Organic chemistry Impact factor: 2.651, year: 2016

  16. Cosmic Ether

    CERN Document Server

    Tomaschitz, R

    1998-01-01

    A prerelativistic approach to particle dynamics is explored in an expanding Robertson-Walker cosmology. The receding galactic background provides a distinguished frame of reference and a unique cosmic time. In this context the relativistic, purely geometric space-time concept is criticized. Physical space is regarded as a permeable medium, the cosmic ether, which effects the world-lines of particles and rays. We study in detail a Robertson-Walker universe with linear expansion factor and negatively curved, open three-space; we choose the permeability tensor of the ether in such a way that the semiclassical approximation is exact. Galactic red-shifts depend on the refractive index of the ether. In the local Minkowskian limit the ether causes a time variation of mass, which scales inversely proportional to cosmic time. In the globally geodesic rest frames of galactic observers the ether manifests itself in an unbounded speed of signal transfer, in bifurcations of world-lines, and in time inversion effects.

  17. Low-density carbonized resorcinol-formaldehyde foams

    International Nuclear Information System (INIS)

    Kong, F.M.; Buckley, S.R.; Giles, C.L. Jr.; Haendler, B.L.; Hair, L.M.; Letts, S.A.; Overturf, G.E. III; Price, C.W.; Cook, R.C.

    1991-01-01

    This report documents research and development on resorcinol- formaldehyde-based foam materials conducted between 1986 and June 1990, when the effort was discontinued. The foams discussed are resorcinol-formaldehyde (RF) foam, carbonized RF (CRF) foam, and two composite foams, a polystyrene/RF (PS/RF) foam and its carbonized derivative (CPR). The RF foams are synthesized by the polycondensation of resorcinol with formaldehyde in a slightly basic solution. Their structure and density depend strongly on the concentration of the sodium carbonate catalyst. The have an interconnected bead structure similar to that of silica aerogels; bead sizes range from 30 to 130 Angstrom, and cell sizes are less than 0.1 μm. We have achieved densities of 16 to 200 mg/cm 3 . The RF foams can be pyrolyzed in an inert atmosphere to form a vitreous carbon foam (CRF), which has a similar microstructure but much higher mechanical strength. The PS/RF foams are obtained by filling the 2- to 3-μm cells of PS foam (a low-density hydrocarbon foam we have developed) with RF. The resultant foams have the outstanding handling and machinability of the PS foam matrix and the small cell size of RF. Pyrolyzing PS/RF foams causes depolymerization and loss of the PS; the resulting CPR foams have a structure similar to the PS foams in which CRF both replicates and fills the PS cells

  18. Synthesis of resorcinolic lipids bearing structural similarities to cytosporone A

    International Nuclear Information System (INIS)

    Santos, Edson dos Anjos dos; Beatriz, Adilson; Lima, Denis Pires de; Marques, Maria Rita; Leite, Carla Braga

    2009-01-01

    Inspired by the structure and biological activities of resorcinolic lipids and, particularly cytosporone A- a potent inhibitor of plantule germination and growth, we have performed the synthesis of the analogs 3-heptyl-3-hydroxy-5,7-dimethoxy-2-benzofuran-1(3H)-one (1) and 3-heptyl-3-hydroxy-4,6-dimethoxy-2-benzofuran-1(3H)-one (2). The intermediates and products were submitted to allelopathic test using Lactuca sativa L. seeds. Target compound 1 showed an inhibitory effect on germination and growth of hypocotyl and radicle in millimolar range. (author)

  19. Synthesis of resorcinolic lipids bearing structural similarities to cytosporone A

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Edson dos Anjos dos; Beatriz, Adilson; Lima, Denis Pires de [Universidade Federal Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Centro de Ciencias Exatas e Tecnologia. Dept. de Quimica], e-mail: dlima@nin.ufms.br; Marques, Maria Rita; Leite, Carla Braga [Universidade Federal Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Centro de Ciencias Biologicas. Dept. de Morfofisiologia

    2009-07-01

    Inspired by the structure and biological activities of resorcinolic lipids and, particularly cytosporone A- a potent inhibitor of plantule germination and growth, we have performed the synthesis of the analogs 3-heptyl-3-hydroxy-5,7-dimethoxy-2-benzofuran-1(3H)-one (1) and 3-heptyl-3-hydroxy-4,6-dimethoxy-2-benzofuran-1(3H)-one (2). The intermediates and products were submitted to allelopathic test using Lactuca sativa L. seeds. Target compound 1 showed an inhibitory effect on germination and growth of hypocotyl and radicle in millimolar range. (author)

  20. Synthesis of resorcinolic lipids bearing structural similarities to cytosporone A

    Directory of Open Access Journals (Sweden)

    Edson dos Anjos dos Santos

    2009-01-01

    Full Text Available Inspired by the structure and biological activities of resorcinolic lipids and, particularly cytosporone A- a potent inhibitor of plantule germination and growth, we have performed the synthesis of the analogs 3-heptyl-3-hydroxy-5,7-dimethoxy-2-benzofuran-1(3H-one (1 and 3-heptyl-3-hydroxy-4,6-dimethoxy-2-benzofuran-1(3H-one (2. The intermediates and products were submitted to allelopathic test using Lactuca sativa L. seeds. Target compound 1 showed an inhibitory effect on germination and growth of hypocotyl and radicle in milimolar range.

  1. Synthesis, structural characterization, and performance evaluation of resorcinol-formaldehyde (R-F) ion-exchange resin

    International Nuclear Information System (INIS)

    Hubler, T.L.; Franz, J.A.; Shaw, W.J.; Bryan, S.A.; Hallen, R.T.; Brown, G.N.; Bray, L.A.; Linehan, J.C.

    1995-08-01

    The 177 underground storage tanks at the DOE's Hanford Site contain an estimated 180 million tons of high-level radioactive wastes. It is desirable to remove and concentrate the highly radioactive fraction of the tank wastes for vitrification. Resorcinol-formaldehyde (R-F) resin, an organic ion-exchange resin with high selectivity and capacity for the cesium ion, which is a candidate ion-exchange material for use in remediation of tank wastes. The report includes information on the structure/function analysis of R-F resin and the synthetic factors that affect performance of the resin. CS-100, a commercially available phenol-formaldehyde (P-F) resin, and currently the baseline ion-exchanger for removal of cesium ion at Hanford, is compared with the R-F resin. The primary structural unit of the R-F resin was determined to consist of a 1,2,3,4-tetrasubstituted resorcinol ring unit while CS-100, was composed mainly of a 1,2,4-trisubstituted ring. CS-100 shows the presence of phenoxy-ether groups, and this may account for the much lower decontamination factor of CS-100 for cesium ion. Curing temperatures for the R-F resin were found to be optimal at 105--130C. At lower temperatures, insufficient curing, hence crosslinking, of the polymer resin occurs and selectivity for cesium drops. Curing at elevated temperatures leads to chemical degradation. Optimal particle size for R-F resin is in the range of 20--50 mesh-sized particles. R-F resin undergoes chemical degradation or oxidation which destroys ion-exchange sites. The ion-exchange sites (hydroxyl groups) are converted to quinones and ketones. CS-100, though it has much lower performance for cesium ion-exchange, is significantly more chemically stable than R-F resin. To gamma radiation, CS-100 is more radiolytically stable than R-F resin

  2. Synthesis, structural characterization, and performance evaluation of resorcinol-formaldehyde (R-F) ion-exchange resin

    Energy Technology Data Exchange (ETDEWEB)

    Hubler, T.L.; Franz, J.A.; Shaw, W.J.; Bryan, S.A.; Hallen, R.T.; Brown, G.N.; Bray, L.A.; Linehan, J.C.

    1995-08-01

    The 177 underground storage tanks at the DOE`s Hanford Site contain an estimated 180 million tons of high-level radioactive wastes. It is desirable to remove and concentrate the highly radioactive fraction of the tank wastes for vitrification. Resorcinol-formaldehyde (R-F) resin, an organic ion-exchange resin with high selectivity and capacity for the cesium ion, which is a candidate ion-exchange material for use in remediation of tank wastes. The report includes information on the structure/function analysis of R-F resin and the synthetic factors that affect performance of the resin. CS-100, a commercially available phenol-formaldehyde (P-F) resin, and currently the baseline ion-exchanger for removal of cesium ion at Hanford, is compared with the R-F resin. The primary structural unit of the R-F resin was determined to consist of a 1,2,3,4-tetrasubstituted resorcinol ring unit while CS-100, was composed mainly of a 1,2,4-trisubstituted ring. CS-100 shows the presence of phenoxy-ether groups, and this may account for the much lower decontamination factor of CS-100 for cesium ion. Curing temperatures for the R-F resin were found to be optimal at 105--130C. At lower temperatures, insufficient curing, hence crosslinking, of the polymer resin occurs and selectivity for cesium drops. Curing at elevated temperatures leads to chemical degradation. Optimal particle size for R-F resin is in the range of 20--50 mesh-sized particles. R-F resin undergoes chemical degradation or oxidation which destroys ion-exchange sites. The ion-exchange sites (hydroxyl groups) are converted to quinones and ketones. CS-100, though it has much lower performance for cesium ion-exchange, is significantly more chemically stable than R-F resin. To gamma radiation, CS-100 is more radiolytically stable than R-F resin.

  3. 78 FR 4792 - Epoxy Polymer; Exemption From the Requirement of a Tolerance

    Science.gov (United States)

    2013-01-23

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 180 [EPA-HQ-OPP-2012-0615; FRL-9364-6] Epoxy Polymer... residues of polymers of one or more diglycidyl ethers of bisphenol A, resorcinol, glycerol... and 1,2,3,6-tetrahydrophthalic anhydride; also referred to as epoxy polymer, when used as an inert...

  4. Resorcinol adsorption from aqueous solution over activated carbon

    International Nuclear Information System (INIS)

    Blanco, Diego A; Giraldo, Liliana; Moreno, Juan C

    2007-01-01

    In this paper, the adsorption behavior of Resorcinol a monohydroxylated phenol, poorly acid to 298 K, over activated carbon is analyzed by studying the solution's pH influence and the surface reduction in the adsorption process. To do this, an activated carbon of lignocellulose origin and a reduced activated carbon was used. The interaction solid solution is characterized by the analyses of adsorption in the isotherms to 298 K and pH values of 7. 00, 9.00 and 11.00 for a period of 48 hours. The capacity adsorption of activated carbons increases when the solution's pH decreases and the retained amount increases in the reduced coal to the pH of maximum adsorption.

  5. Reactivity of Resorcinol Formaldehyde Resin with Nitric Acid

    International Nuclear Information System (INIS)

    King, William D.; Fondeur, Fernando F.; Wilmarth, William R.; Pettis, Myra E.

    2005-01-01

    Solid-state infrared spectroscopy, differential scanning calorimetry, and elemental analysis have been used to evaluate the reactivity of resorcinol formaldehyde resin with nitric acid and characterize the solid product. Two distinct reactions were identified within the temperature range 25-55 C. The first reaction is primarily associated with resin nitration, while the second involves bulk oxidation and degradation of the polymer network leading to dissolution and off-gassing. The threshold conditions promoting reaction have been identified. Reaction was confirmed with nitric acid concentrations as low as 3 M at 25 C applied temperature and 0.625 M at 66 C. Although a nitrated resin product can be isolated under appropriate experimental conditions, calorimetry testing indicates no significant hazard associated with handling the dry material

  6. Crosslinking of epoxy-oligoesteric mixtures in the presence of dioxydiphenylpropane diglycidyl ether modified with adipic acid

    Czech Academy of Sciences Publication Activity Database

    Bratychak, M.; Zubal, O.; Bashta, Bogdana; Ivashkiv, O.; Shyshchak, O.; Haponiuk, J.

    2017-01-01

    Roč. 11, č. 2 (2017), s. 180-187 ISSN 1996-4196 Institutional support: RVO:61389013 Keywords : crosslinking * polymer films * epoxy resin Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science

  7. Misconceptions about the ether

    International Nuclear Information System (INIS)

    Duffy, M.C.

    1980-01-01

    Several misconceptions concerning the ether concept and ether models are reviewed and clarified so that the relationship between modern ether theory and orthodox relativity may be better understood. The question of the ether's supposed superfluidity as a concept, and its status in modern physics remains to be answered. (author)

  8. Melamine-bridged alkyl resorcinol modified urea - formaldehyde resin for bonding hardwood plywood

    Science.gov (United States)

    Chung-Yun Hse; Mitsuo Higuchi

    2010-01-01

    A powdery product was obtained by the reaction of methylolated melamine with alkyl resorcinols to form melamine-bridged alkyl resorcinols (MARs). The effects of the addition of this powder on the bonding strength and formaldehyde emission of urea–formaldehyde (UF) resins were investigated. Three types of UF resins with a formaldehyde/urea molar ratio of 1.3 synthesized...

  9. Bimodal activated carbons derived from resorcinol-formaldehyde cryogels

    Science.gov (United States)

    Szczurek, Andrzej; Amaral-Labat, Gisele; Fierro, Vanessa; Pizzi, Antonio; Celzard, Alain

    2011-01-01

    Resorcinol-formaldehyde cryogels prepared at different dilution ratios have been activated with phosphoric acid at 450 °C and compared with their carbonaceous counterparts obtained by pyrolysis at 900 °C. Whereas the latter were, as expected, highly mesoporous carbons, the former cryogels had very different pore textures. Highly diluted cryogels allowed preparation of microporous materials with high surface areas, but activation of initially dense cryogels led to almost non-porous carbons, with much lower surface areas than those obtained by pyrolysis. The optimal acid concentration for activation, corresponding to stoichiometry between molecules of acid and hydroxyl groups, was 2 M l−1, and the acid–cryogel contact time also had an optimal value. Such optimization allowed us to achieve surface areas and micropore volumes among the highest ever obtained by activation with H3PO4, close to 2200 m2 g−1 and 0.7 cm3 g−1, respectively. Activation of diluted cryogels with a lower acid concentration of 1.2 M l−1 led to authentic bimodal activated carbons, having a surface area as high as 1780 m2 g−1 and 0.6 cm3 g−1 of microporous volume easily accessible through a widely developed macroporosity. PMID:27877405

  10. Bimodal activated carbons derived from resorcinol-formaldehyde cryogels

    Energy Technology Data Exchange (ETDEWEB)

    Szczurek, Andrzej; Amaral-Labat, Gisele; Fierro, Vanessa; Celzard, Alain [Institut Jean Lamour-UMR CNRS 7198, CNRS-Nancy-Universite-UPV-Metz, Departement Chimie et Physique des Solides et des Surfaces. ENSTIB, 27 rue Philippe Seguin, BP 1041, 88051 Epinal cedex 9 (France); Pizzi, Antonio, E-mail: Alain.Celzard@enstib.uhp-nancy.fr [ENSTIB-LERMAB, Nancy-Universite, 27 rue Philippe Seguin, BP1041, 88051 Epinal cedex 9 (France)

    2011-06-15

    Resorcinol-formaldehyde cryogels prepared at different dilution ratios have been activated with phosphoric acid at 450 deg. C and compared with their carbonaceous counterparts obtained by pyrolysis at 900 deg. C. Whereas the latter were, as expected, highly mesoporous carbons, the former cryogels had very different pore textures. Highly diluted cryogels allowed preparation of microporous materials with high surface areas, but activation of initially dense cryogels led to almost non-porous carbons, with much lower surface areas than those obtained by pyrolysis. The optimal acid concentration for activation, corresponding to stoichiometry between molecules of acid and hydroxyl groups, was 2 M l{sup -1}, and the acid-cryogel contact time also had an optimal value. Such optimization allowed us to achieve surface areas and micropore volumes among the highest ever obtained by activation with H{sub 3}PO{sub 4}, close to 2200 m{sup 2} g{sup -1} and 0.7 cm{sup 3} g{sup -1}, respectively. Activation of diluted cryogels with a lower acid concentration of 1.2 M l{sup -1} led to authentic bimodal activated carbons, having a surface area as high as 1780 m{sup 2} g{sup -1} and 0.6 cm{sup 3} g{sup -1} of microporous volume easily accessible through a widely developed macroporosity.

  11. Application of cross-linked soy protein isolate with resorcinol films for release studies of naturally occurring bioactive agent with antiproliferative activity

    CSIR Research Space (South Africa)

    Siva Mohan Reddy, G

    2014-01-01

    Full Text Available The potential of soy protein isolate films as a release system for naturally occurring antiproliferative agent was investigated. The soy protein isolates was cross linked with resorcinol and the resorcinol content was varied between 10...

  12. Dual Studies on a Hydrogen-Deuterium Exchange of Resorcinol and the Subsequent Kinetic Isotope Effect

    Science.gov (United States)

    Giles, Richard; Kim, Iris; Chao, Weyjuin Eric; Moore, Jennifer; Jung, Kyung Woon

    2014-01-01

    An efficient laboratory experiment has been developed for undergraduate students to conduct hydrogen-deuterium (H-D) exchange of resorcinol by electrophilic aromatic substitution using D[subscript 2]O and a catalytic amount of H[subscript 2]SO[subscript 4]. The resulting labeled product is characterized by [superscript 1]H NMR. Students also…

  13. The influence of hydrogen peroxide on the permeability of protective gloves to resorcinol in hairdressing.

    Science.gov (United States)

    Lind, Marie-Louise; Johnsson, Stina; Lidén, Carola; Meding, Birgitta; Boman, Anders

    2015-01-01

    Hairdressers are exposed to hair dye chemicals, for example resorcinol and hydrogen peroxide. Adequate skin protection is an important preventive measure against occupational skin disease. To examine whether hydrogen peroxide may cause deterioration of protective gloves. Permeation of resorcinol through gloves of polyvinylchloride (PVC) (n = 8), natural rubber latex (NRL) (n = 5) and nitrile rubber (NR) (n = 5) was studied in a two-compartment cell, with resorcinol as an indicator for hair dyes. The amount of resorcinol that had permeated was analysed with a high-performance liquid chromatography instrument. Cumulative breakthrough time and permeation rate were compared for hydrogen peroxide-pretreated and untreated gloves. The cumulative breakthrough time was > 1 hr but gloves. Pretreatment of PVC gloves resulted in a slightly decreased breakthrough time, and pretreatment of NRL gloves decreased the permeation rate. No change was recorded in NR gloves. Treatment with hydrogen peroxide had a minor effect on permeation in the tested gloves. NR gloves provided the best protection. However, taking the allergy risk of rubber gloves into account, plastic gloves are recommended in hairdressing. PVC gloves may be used, but not for > 1 hr. Disposable gloves should never be reused, regardless of material. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Resorcinol adsorption from aqueous solution on activated carbon: Relation adsorption isotherm and immersion enthalpy

    International Nuclear Information System (INIS)

    Blanco, Diago A; Giraldo, Liliana; Moreno, Juan C.

    2008-01-01

    The resorcinol adsorption on a modified activated carbon, obtained from an activated commercial carbon Carbochem T M - PS30, CAG, modified by means of chemical treatment with HNO 3 7M oxidized activated carbon (CAO) and heat treatment under H 2 flow, reduced activated carbon (CAR) are studied. The influence of solution pH, the reduction and oxidation of the activated surface carbons in resorcinol aqueous solutions is determined. The interaction solid solution is characterized by adsorption isotherms analysis at 298 K and at pHs of 7.9 and 11 in order to evaluate the system on and below the value of resorcinol pKa. The adsorption capacity of carbons increases with diminishing solution pH. The amount retained increases in the reduced carbon at maximum adsorption pH and diminishes in the oxidized carbon. the experimental results of the adsorption isotherms are adjusted to the Freundlich and Langmuir models, obtaining values for the Q m ax parameter Langmuir model in the CAG of 179, 156 and 44 mgg - 1 For pH values of 7,9 and 11 respectively. In this case of modified carbons values of 233, 179 and 164 mgg - 1 Are obtained for CAR, CAG and CAO to pH 7 respectively, as general tendency the resorcinol adsorption increases in the following order CAR > CAG > CAO. Similar conclusions from immersion enthalpies are obtained, their values increase with the amount of solute retained. In the case of the CAG, immersion enthalpies between 25.8 to 40.9 Jg - 1, are obtained for resorcinol aqueous solutions in a range from 20 to 1500 mgL - 1

  15. Ether formulations of relativity

    International Nuclear Information System (INIS)

    Duffy, M.C.

    1980-01-01

    Contemporary ether theories are surveyed and criticised, especially those formally identical to orthodox Relativity. The historical development of Relativity, Special and General, in terms of an ether, is briefly indicated. Classical interpretations of Generalized Relativity using ether are compared to Euclidean formulations using a background space. The history of a sub-group of theories, formulating a 'new' Relativity involving modified transforms, is outlined. According to the theory with which they agree, recent supposed detections of drift are classified and criticised. Cosmological evidence suggesting an ether is mentioned. Only ether theories formally identical to Relativity have been published in depth. They stand criticised as being contrary to the positivist spirit. The history of mechanical analogues is traced, from Hartley's representing gravitating matter as spherical standing waves, to recent suggestions that vortex-sponge might model electromagnetic, quantum, uncertainty and faster-than-light phenomena. Contemporary theories are particular physical theories, themselves 'second interpretations' of a primary mathematical model. Mechanical analogues are auxiliary, not necessary, to other theory, disclosing relationships between classical and non-classical descriptions of assemblies charging state. The ether-relativity polemic, part of a broader dispute about relativity, is founded on mistaken conceptions of the roles of mathematical and physical models, mechanical analogues; and a distored view of history, which indicates that ether theories have become relativistic. (author)

  16. Lawps ion exchange column gravity drain of spherical resorcinol formaldehyde resin

    Energy Technology Data Exchange (ETDEWEB)

    Duignan, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Herman, D. T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Restivo, M. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-01-28

    Experiments at several different scales were performed to understand the removal of spherical resorcinol formaldehyde (sRF) ion exchange resin using a gravity drain system with a valve located above the resin screen in the ion exchange column (IXC). This is being considered as part of the design for the Low Activity Waste Pretreatment System (LAWPS) to be constructed at the DOE Hanford Site.

  17. Chemical derivatization to enhance chemical/oxidative stability of resorcinol-formaldehyde resin

    Energy Technology Data Exchange (ETDEWEB)

    Hubler, T.L. [Pacific Northwest National Lab., Richland, WA (United States)

    1997-10-01

    The goal of this task is to develop modified resorcinol-formaldehyde (R-F) resin to improve the chemical/oxidative stability of the resin. R-F resin is a regenerable organic ion-exchange resin that is selective for cesium ion in highly alkaline, high ionic-strength solutions. R-F resin tends to undergo chemical degradation, reducing its ability to remove cesium ion from waste solutions; the mechanistic details of these decomposition reactions are currently unknown. The approach used for this task is chemical modification of the resin structure, particularly the resorcinol ring unit of the polymer resin. This approach is based on prior characterization studies conducted at Pacific Northwest National Laboratory (PNNL) that indicated the facile chemical degradation of the resin is oxidation of the resorcinol ring to the para-quinone structure, with subsequent loss of ion-exchange sites for cesium ion. R-F resin represents an important alternative to current radiocesium remediation technology for tank wastes at both the Hanford and Savannah River sites, particularly if regenerable resins are needed.

  18. Real time in situ spectroscopic characterization of radiation induced cationic polymerization of glycidyl ethers

    International Nuclear Information System (INIS)

    Mascioni, Matteo; Sands, James M.; Palmese, Giuseppe R.

    2003-01-01

    Radiation curable polymeric materials suffer from relatively poor mechanical properties. Moreover, the curing behavior of such systems (i.e. the exact relationship between chemical kinetics and key processing variables) is not fully understood. In order to design improved epoxy based electron beam (EB) curable systems, and in order to develop appropriate process models, a detailed knowledge of the kinetics of epoxy cationic polymerization induced by ultraviolet (UV) or EB irradiation is required. In this work, we present our development of a technique based on real time near infrared (RTIR) spectroscopy for performing in situ kinetic analysis of radiation induced cationic polymerization of epoxy systems. To our knowledge this is the first time such data have been collected and presented for high-energy EB (10 MeV) induced polymerization. A demonstration of the technique for deterministic evaluation of degree of cure is shown using model glycidyl ether (phenyl glycidyl ether and diglycidyl ether of bisphenol A) resins and isothermal curing conditions. The impact of initiation rate on polymerizations with UV and EB for the cationic initiator is directly evident by comparative analysis. The sensitivity of the RTIR method and ability to produce quantitative data evidence of reaction mechanisms is demonstrated. The type of data presented in this work forms the basis for cure models being developed

  19. Usage of the word 'ether'

    International Nuclear Information System (INIS)

    Duffy, M.C.

    1980-01-01

    Confusion has been caused by scientists using the one word 'ether' to classify models differing from each other in important respects. Major roles assigned to the word are examined, and the nature of modern ether theories surveyed. The part played by the several meanings attached to the word, in the ether concept, is outlined. (author)

  20. Synthesis and application of a novel environmental C26 diglycidyl ester plasticizer based on castor oil for poly(vinyl chloride)

    Science.gov (United States)

    In this work, for the first time, a castor oil derived diglycidyl ester plasticizer (C26-DGE) was prepared and incorporated into poly(vinyl chloride) (PVC). The chemical structure of the product was characterized by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (...

  1. Electrochemical Degradation of Phenol and Resorcinol Molecules through the Dissolution of Sacrificial Anodes of Macro-Corrosion Galvanic Cells

    Directory of Open Access Journals (Sweden)

    Boguslaw Pierozynski

    2018-06-01

    Full Text Available This paper reports on the processes of phenol and resorcinol electrodegradation carried-out through continuous anodic dissolution of aluminum alloy and carbon steel sacrificial anodes for artificially aerated Cu-Al alloy and Cu-Fe-based galvanic (macro-corrosion cells and synthetically prepared wastewater solutions. Electrochemical experiments were carried-out by means of a laboratory size, PMMA (Poly-methyl methacrylate-made electrolyser unit, where significant degrees of phenol (10–89% and resorcinol (13–37% decomposition were obtained and visualized through the respective chemical/spectroscopy analyses. In addition, quantitative determination of phenol, as well as resorcinol (and possible electrodegradation products for the selected experimental conditions was performed by means of instrumental high-performance liquid chromatography/mass spectrometry analysis.

  2. Concentrating cesium-137 from seawater using resorcinol-formaldehyde resin for radioecological monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Egorin, Andrei; Tokar, Eduard; Tutov, Mikhail; Avramenko, Valentin [Institute of Chemistry FEBRAS, Vladivostok (Russian Federation); Far Eastern Federal Univ., Vladivostok (Russian Federation); Palamarchuk, Marina; Marinin, Dmitry [Institute of Chemistry FEBRAS, Vladivostok (Russian Federation)

    2017-04-01

    A method of preconcentrating cesium-137 from seawater using a resorcinol-formaldehyde resin, which enables one to optimize the ecological monitoring procedure, has been suggested. Studies of sorption of cesium-137 from seawater by resorcinol-formaldehyde resin have been performed, and it has been demonstrated that the cation exchanger is characterized by high selectivity with respect to cesium-137. It was found that the selectivity depended on the temperature of resin solidification and the seawater pH value. The maximal value of the cesium-137 distribution coefficient is equal to 4.1-4.5 x 10{sup 3} cm{sup 3} g{sup -1}. Under dynamic conditions, the ion-exchange resin capacity is 310-910 bed volumes depending on the seawater pH, whereas the efficiency of cesium removal exceeds 95%. The removal of more than 95% of cesium-137 has been attained using 1-3 M solutions of nitric acid: here, the eluate volume was 8-8.4 bed volumes. Application of 3 M solution of nitric acid results in resin degradation with the release of gaseous products.

  3. Photostabilizing of bisphenol A polycarbonate by using UV-absorbers and self protective block copolymers based on resorcinol polyarylate blocks

    NARCIS (Netherlands)

    Diepens, M.; Gijsman, P.

    2009-01-01

    Bisphenol A polycarbonate degrades due to sunlight, humidity and oxygen. In this study two possible techniques to stabilize the polymer were compared, i.e. blending of UV-absorbers (UVAs) into the polymer or using block copolymers based on resorcinol polyarylates. Combination of different analysis

  4. Cesium Isotherm Testing with Spherical Resorcinol-Formaldehyde Resin at High Sodium Concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Russell, Renee L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fiskum, Sandra K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Smoot, Margaret R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rinehart, Donald E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-04-01

    Washington River Protection Solutions (WRPS) is developing a Low-Activity Waste Pretreatment System (LAWPS) to provide low-activity waste (LAW) directly to the Hanford Tank Waste Treatment and Immobilization Plant (WTP) Low-Activity Waste Facility for immobilization. The pretreatment that will be conducted on tank waste supernate at the LAWPS facility entails filtration to remove entrained solids and cesium (Cs) ion exchange to remove Cs from the product sent to the WTP. Currently, spherical resorcinol-formaldehyde (sRF) resin (Microbeads AS, Skedsmokorset, Norway) is the Cs ion exchange resin of choice. Most work on Cs ion exchange efficacy in Hanford tank waste has been conducted at nominally 5 M sodium (Na). WRPS is examining the possibility of processing supernatant at high Na concentrations—up to 8 M Na—to maximize processing efficiency through the LAWPS. Minimal Cs ion exchange work has been conducted at 6 M and 8 M Na concentrations..

  5. Decontamination of spent ion-exchangers contaminated with cesium radionuclides using resorcinol-formaldehyde resins.

    Science.gov (United States)

    Palamarchuk, Marina; Egorin, Andrey; Tokar, Eduard; Tutov, Mikhail; Marinin, Dmitry; Avramenko, Valentin

    2017-01-05

    The origin of the emergence of radioactive contamination not removable in the process of acid-base regeneration of ion-exchange resins used in treatment of technological media and liquid radioactive waste streams has been determined. It has been shown that a majority of cesium radionuclides not removable by regeneration are bound to inorganic deposits on the surface and inside the ion-exchange resin beads. The nature of the above inorganic inclusions has been investigated by means of the methods of electron microscopy, IR spectrometry and X-ray diffraction. The method of decontamination of spent ion-exchange resins and zeolites contaminated with cesium radionuclides employing selective resorcinol-formaldehyde resins has been suggested. Good prospects of such an approach in deep decontamination of spent ion exchangers have been demonstrated. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Evaluations of Mechanisms for Pu Uptake and Retention within Spherical Resorcinol-Formaldehyde Resin Columns

    Energy Technology Data Exchange (ETDEWEB)

    Delegard, Calvin H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Levitskaia, Tatiana G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fiskum, Sandra K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-15

    The unexpected uptake and retention of plutonium (Pu) onto columns containing spherical resorcinol-formaldehyde (sRF) resin during ion exchange testing of Cs (Cs) removal from alkaline tank waste was observed in experiments at both the Pacific Northwest National Laboratory (PNNL) and the Savannah River National Laboratory (SRNL). These observations have raised concern regarding the criticality safety of the Cs removal unit operation within the low-activity waste pretreatment system (LAWPS). Accordingly, studies have been initiated at Washington River Protection Solutions (WRPS), who manages the operations of the Hanford Site tank farms, including the LAWPS, PNNL, and elsewhere to investigate these findings. As part of these efforts, PNNL has prepared the present report to summarize the laboratory testing observations, evaluate these phenomena in light of published and unpublished technical information, and outline future laboratory testing, as deemed appropriate based on the literature studies, with the goal to elucidate the mechanisms for the observed Pu uptake and retention.

  7. Reproductive toxicity of the glycol ethers.

    Science.gov (United States)

    Hardin, B D

    1983-06-01

    The glycol ethers are an important and widely used class of solvents. Recent studies have demonstrated that ethylene glycol monomethyl ether (EGME), ethylene glycol dimethyl ether (EGdiME), ethylene glycol monoethyl ether (EGEE), and ethylene glycol monoethyl ether acetate (EGEEA) are teratogenic. Other studies have demonstrated that testicular atrophy or infertility follow treatment of males with EGME, ethylene glycol monomethyl ether acetate (EGMEA), EGEE, EGEEA, diethylene glycol dimethyl ether (diEGdiME), and diethylene glycol monoethyl ether (diEGEE). Experimental data are reviewed and structure-activity relationships are speculated upon.

  8. Preparation and Characterization of Sulfonated Poly (ether ether ...

    African Journals Online (AJOL)

    NJD

    2007-08-10

    Aug 10, 2007 ... Preparation and Characterization of Sulfonated Poly (ether ... Currently perfluori- ... with phosphoric acid solution according to the method described earlier.11,12 ... where A is the membrane area available for diffusion; CA is.

  9. Ether the nothing that connects everything

    CERN Document Server

    Milutis, Joe

    2006-01-01

    In Ether, the histories of the unseen merge with discussions of the technology of electromagnetism. Navigating more than three hundred years of the ether''s cultural and artistic history, Joe Milutis reveals its continuous reinvention and tangible impact without ever losing sight of its ephemeral, elusive nature. The true meaning of ether, Milutis suggests, may be that it can never be fully grasped.

  10. Evolution of mechanical properties and final textural properties of resorcinol-formaldehyde xerogels during ambient air drying

    OpenAIRE

    Léonard, Angélique; Blacher, Silvia; Crine, Michel; Jomaa, Wahbi

    2008-01-01

    Porous carbon xerogels can be obtained by convective drying of resorcinol (R)-formaldehyde (F) hydrogels, followed by pyrolysis. Drying conditions have to be carefully controlled when crack-free monoliths with well-defined shape and size are required. The knowledge of the mechanical properties of the RF xerogels and their evolution with water content is essential to model their thermo-hygro-mechanical behavior during convective drying and avoid mechanical stresses leading to deformation and c...

  11. Chemoselective Deprotection of Triethylsilyl Ethers

    Science.gov (United States)

    Chandra, Tilak; Broderick, William E.; Broderick, Joan B.

    2009-01-01

    An efficient and selective method was developed for the deprotection of triethylsilyl (TES) ethers using formic acid in methanol (5–10%) or in methylene chloride 2–5%) with excellent yields. TES ethers are selectively deprotected to the corresponding alcohols in high yields using formic acid in methanol under mild reaction conditions. Other hydroxyl protecting groups like t-butyldimethylsilyl (TBDMS) remain unaffected. PMID:20183570

  12. Rearrangements of Cycloalkenyl Aryl Ethers

    Directory of Open Access Journals (Sweden)

    Mercedesz Törincsi

    2016-04-01

    Full Text Available Rearrangement reactions of cycloalkenyl phenol and naphthyl ethers and the acid-catalyzed cyclization of the resulting product were investigated. Claisen rearrangement afforded 2-substituted phenol and naphthol derivatives. Combined Claisen and Cope rearrangement resulted in the formation of 4-substituted phenol and naphthol derivatives. In the case of cycloocthylphenyl ether the consecutive Claisen and Cope rearrangements were followed by an alkyl migration. The mechanism of this novel rearrangement reaction is also discussed.

  13. Ether: Bitcoin's competitor or ally?

    OpenAIRE

    Bouoiyour, Jamal; Selmi, Refk

    2017-01-01

    Although Bitcoin has long been dominant in the crypto scene, it is certainly not alone. Ether is another cryptocurrency related project that has attracted an intensive attention because of its additional features. This study seeks to test whether these cryptocurrencies differ in terms of their volatile and speculative behaviors, hedge, safe haven and risk diversification properties. Using different econometric techniques, we show that a) Bitcoin and Ether are volatile and relatively more resp...

  14. Electrogeneration of disinfection byproducts at a boron-doped diamond anode with resorcinol as a model substance

    International Nuclear Information System (INIS)

    Li Hongna; Ni Jinren

    2012-01-01

    Highlights: ► DBPs formation was studied in BDD cell with several organics. ► Accumulated chloroform was wholly mineralized in the electrolysis. ► Chlorate produced was oxidized to perchlorate as electrolysis continued. ► Inorganic byproducts should be carefully watched in electrolysis with BDD. ► Resorcinol had the greatest reactivity for DBPs production in the studied precursors. - Abstract: Electrochemical disinfection in chloride electrolyte with a boron-doped diamond (BDD) electrode has unique advantages due to the high oxidizing ability of active chlorine and reactive oxygen species produced under certain conditions in the electrolysis. However, the electrogeneration of disinfection byproducts (DBPs) in the presence of organics in the system has rarely been reported. In this study, the discontinuous formation of DBPs (chloroform, chlorate and perchlorate) was investigated in model water containing chloride electrolyte (10 mM) with a BDD anode in the presence of resorcinol (0.5 mM) at a current density of 20 mA cm −2 . We found that the formation of chloroform and chlorate increased with the free available chlorine production at the beginning and reached peaks at 2 h (0.01 mM), 4 h (1.67 mM), respectively. When the free available chlorine started to decrease, chloroform was gradually mineralized and chlorate was oxidized to perchlorate due to the strong and non-selective oxidizing ability of the BDD. After electrolysis for 25 h, only perchlorate was left (3.84 mM). So inorganic DBPs should be carefully watched in the BDD system. The chloride concentration in the electrolyte affected the production of all three DBPs, due to its influence on the active chlorine production. Organic was not involved in the chlorate and perchlorate formation, and thus the resorcinol concentration had little impact on inorganic DBPs. DBPs formation at acidic pH was lower than that in the basic condition, mainly due to the different forms of resorcinol and chlorine

  15. Structural, absorption, and molecular properties of o,o'-dihydroxyazo resorcinol dyes bearing an acryloyloxy group

    Science.gov (United States)

    Özkınalı, Sevil; Çavuş, M. Serdar; Ceylan, Abdullah; Gür, Mahmut

    2017-12-01

    To the best of our knowledge, this is the first study reporting the synthesis and characterization of o,o‧-dihydroxyazo dyes bearing an acryloyl group. The o,o‧-dihydroxyazo dyes were synthesized through coupling of resorcinol with the diazonium salts of 2-amino-4-methylphenol, 2-aminophenol, 2-amino-4-chlorophenol, and 2-amino-4-nitrophenol. Their acryloyl derivatives were synthesized using metallic sodium and acryloyl chloride under an inert atmosphere. Characterization of the compounds was conducted using infrared (IR), ultraviolet-visible (UV-vis), proton nuclear magnetic resonance (1H NMR), and carbon nuclear magnetic resonance (13C NMR) spectroscopic methods. The tautomerism of the synthesized compounds' was also evaluated. The results were compared with theoretical results obtained by density functional theory (DFT). The DFT calculations were performed to obtain ground-state optimized geometries and calculate the relevant electronic and chemical reactivity parameters. Furthermore, possible tautomers deduced from the UV-vis spectra were investigated using theoretical calculations. Both the IR and NMR spectral data showed that azo tautomers predominate in the solid state and DMSO solvent. The effects of pH, solvent, and substituent on the predominant tautomers were further investigated through UV-vis spectroscopy. The results indicate that hydrazone tautomers were dominant at pH 12 in dimethylformamide (DMF), whereas azo tautomers were dominant at pH 2 in EtOH or CHCl3.

  16. Spectrophotometric Determination of Gallium(III with 4-(2-Pyridylazo-resorcinol and Nitron

    Directory of Open Access Journals (Sweden)

    Petya Vassileva Racheva

    2015-07-01

    Full Text Available The formation and liquid-liquid extraction of ion-association complex between gallium(III − 4-(2-pyridylazo-resorcinol (PAR – 1,4-diphenyl-3-(phenylamino-1H-1,2,4-triazole (nitron, Nt, water and chloroform were studied. The optimum conditions for gallium(III extraction as an ion-association complex, (NtH+[Ga3+(PAR2]-, were found: pH, concentration of the reagents and shaking time. The following key constants were calculated: constant of extraction (logKex = 6.28 ± 0.07, constant of association (logβ = 4.98 ± 0.05, constant of distribution (logKD = 1.30 ± 0.02 and recovery factor (R / % = 95.17 ± 0.02. Beerʼs law is obeyed for Ga(III concentration up to 0.8 μg cm-3 with apparent molar absorptivity of (10.3 ± 0.4×104 dm-3 mol-1 cm-1 at λmax = 510 nm. Some additional characteristics, such as limit of detection (LOD = 0.072 μg cm-3, limit of quantification (LOQ = 0.24 μg cm-3 and Sandellʼs sensitivity (SS = 0.000675 ng cm-2 were estimated as well.

  17. Fire Safety Tests for Spherical Resorcinol Formaldehyde Resin: Data Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong-Sang; Peterson, Reid A.; Schweiger, Michael J.

    2012-07-30

    A draft safety evaluation of the scenario for spherical resorcinol-formaldehyde (SRF) resin fire inside the ion exchange column was performed by the Hanford Tank Waste Treatment and Immobilization Plant (WTP) Fire Safety organization. The result of this draft evaluation suggested a potential change of the fire safety classification for the Cesium Ion Exchange Process System (CXP) emergency elution vessels, equipment, and piping, which may be overly bounding based on the fire performance data from the manufacturer of the ion exchange resin selected for use at the WTP. To resolve this question, the fire properties of the SRF resin were measured by Southwest Research Institute (SwRI), following the American Society for Testing and Materials (ASTM) standard procedures, through a subcontract managed by Pacific Northwest National Laboratory (PNNL). For some tests, the ASTM standard procedures were not entirely appropriate or practical for the SRF resin material, so the procedures were modified and deviations from the ASTM standard procedures were noted. This report summarizes the results of fire safety tests performed and reported by SwRI. The efforts by PNNL were limited to summarizing the test results provided by SwRI into one consolidated data report. All as-received SwRI reports are attached to this report in the Appendix. Where applicable, the precision and bias of each test method, as given by each ASTM standard procedure, are included and compared with the SwRI test results of the SRF resin.

  18. FABRICATION AND PROPERTIES OVERCOATED RESORCINOL-FORMALDEHYDE SHELLS FOR OMEGA EXPERIMENTS

    International Nuclear Information System (INIS)

    NIKROO, A; CZECHOWICZ, D; PAGUIO, R; GREENWOOD, A.L; TAKAGI, M.

    2003-09-01

    OAK-B135 New high gain designs for direct drive ignition on NIF require foam shells. Scaled down versions of these designs are needed for near term experiments on the OMEGA laser facility at the Laboratory Laser Energetics (LLE). These shells need to be about 1 mm in diameter and 50-100 (micro)m wall thickness and densities of 100-250 mg/cc. In addition, a full density permeation seal needs to be deposited for retention of the fill gas at room temperature or the ice at cryogenic temperatures. They have fabricated such shells using Resorcinol-formaldehyde (R/F) as the selected foam material due to its transparency in the optical region. Extensive characterization of the wall uniformity of these shells has been performed. The foam shells have ∼ 5%-6% non-concentricities on the average. A full density permeation seal has been deposited on the R/F shells using two different techniques. In the first technique R/F shells are coated directly with plasma polymer to thicknesses of 3-4 (micro)m. In the second technique, R/F shells are coated with polyvinylphenol, using a chemical interfacial polymerization technique. Data on surface finish and gas retention for R/F shells coated by both methods are provided

  19. Simultaneous Determination of Hydroquinone, Catechol and Resorcinol at Graphene Doped Carbon Ionic Liquid Electrode

    Directory of Open Access Journals (Sweden)

    Li Ma

    2012-01-01

    Full Text Available A new composite electrode has been prepared with doping graphene into the paste consisting graphite and ionic liquid, n-octyl-pyridinum hexafluorophosphate (OPFP. This electrode shows an excellent electrochemical activity for the redox of hydroquinone (HQ, catechol (CC, and resorcinol (RS. In comparison with bare paste electrode, the redox peaks of three isomers of dihydroxybenzene can be obviously, simultaneously observed at graphene doping paste electrode. Under the optimized condition, the simultaneous determination of HQ, CC, and RS in their ternary mixture can be carried out with a differential pulse voltammetric technique. The peak currents are linear to the concentration of HQ, CC, and RS in the range form 1×10−5 to 4×10−4, 1×10−5 to 3×10−4, and 1×10−6 to 1.7×10−4 mol L−1, respectively. The limits of detection are 1.8×10−6 mol L−1 for HQ, 7.4×10−7 mol L−1 for CC, and 3.6×10−7 M for RS, respectively.

  20. Resorcinol-, catechol- and saligenin-based bronchodilating β2-agonists as inhibitors of human cholinesterase activity.

    Science.gov (United States)

    Bosak, Anita; Knežević, Anamarija; Gazić Smilović, Ivana; Šinko, Goran; Kovarik, Zrinka

    2017-12-01

    We investigated the influence of bronchodilating β2-agonists on the activity of human acetylcholinesterase (AChE) and usual, atypical and fluoride-resistant butyrylcholinesterase (BChE). We determined the inhibition potency of racemate and enantiomers of fenoterol as a resorcinol derivative, isoetharine and epinephrine as catechol derivatives and salbutamol and salmeterol as saligenin derivatives. All of the tested compounds reversibly inhibited cholinesterases with K i constants ranging from 9.4 μM to 6.4 mM and had the highest inhibition potency towards usual BChE, but generally none of the cholinesterases displayed any stereoselectivity. Kinetic and docking results revealed that the inhibition potency of the studied compounds could be related to the size of the hydroxyaminoethyl chain on the benzene ring. The additional π-π interaction of salmeterol's benzene ring and Trp286 and hydrogen bond with His447 probably enhanced inhibition by salmeterol which was singled out as the most potent inhibitor of all the cholinesterases.

  1. Gas Generation Testing of Spherical Resorcinol-Formaldehyde (sRF) Resin

    Energy Technology Data Exchange (ETDEWEB)

    Colburn, Heather A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bryan, Samuel A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Camaioni, Donald M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mahoney, Lenna A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Adami, Susan R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2018-01-19

    This report describes gas generation testing of the spherical resorcinol-formaldehyde (sRF) resin that was conducted to support the technology maturation of the LAWPS facility. The current safety basis for the LAWPS facility is based primarily on two studies that had limited or inconclusive data sets. The two studies indicated a 40% increase in hydrogen generation rate of water (as predicted by the Hu model) with sRF resin over water alone. However, the previous studies did not test the range of conditions (process fluids and temperatures) that are expected in the LAWPS facility. Additionally, the previous studies did not obtain replicate test results or comparable liquid-only control samples. All of the testing described in this report, conducted with water, 0.45M nitric acid, and waste simulants with and without sRF resin, returned hydrogen generation rates that are within the current safety basis for the facility of 1.4 times the Hu model output for water.

  2. Ion Exchange Modeling Of Cesium Removal From Hanford Waste Using Spherical Resorcinol-Formaldehyde Resin

    Energy Technology Data Exchange (ETDEWEB)

    Aleman, S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hamm, L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Smith, F. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2007-06-27

    This report discusses the expected performance of spherical Resorcinol-Formaldehyde (RF) ion exchange resin for the removal of cesium from alkaline Hanford radioactive waste. Predictions of full scale column performance in a carousel mode are made for the Hot Commissioning, Envelope B, and Subsequent Operations waste compositions under nominal operating conditions and for perturbations from the nominal. Only the loading phase of the process cycle is addressed in this report. Pertinent bench-scale column tests, kinetic experiments, and batch equilibrium experiments are used to estimate model parameters and to benchmark the ion-exchange model. The methodology and application presented in this report reflect the expected behavior of spherical RF resin manufactured at the intermediate-scale (i.e., approximately 100 gallon batch size; batch 5E-370/641). It is generally believed that scale-up to production-scale in resin manufacturing will result in similarly behaving resin batches whose chemical selectivity is unaffected while total capacity per gram of resin may vary some. As such, the full-scale facility predictions provided within this report should provide reasonable estimates of production-scale column performance.

  3. Hair Dyes Resorcinol and Lawsone Reduce Production of Melanin in Melanoma Cells by Tyrosinase Activity Inhibition and Decreasing Tyrosinase and Microphthalmia-Associated Transcription Factor (MITF Expression

    Directory of Open Access Journals (Sweden)

    Shu-Mei Lee

    2015-01-01

    Full Text Available Hair coloring products are one of the most important cosmetics for modern people; there are three major types of hair dyes, including the temporary, semi-permanent and permanent hair dyes. The selected hair dyes (such as ammonium persulfate, sodium persulfate, resorcinol and lawsone are the important components for hair coloring products. Therefore, we analyzed the effects of these compounds on melanogenesis in B16-F10 melanoma cells. The results proved that hair dyes resorcinol and lawsone can reduce the production of melanin. The results also confirmed that resorcinol and lawsone inhibit mushroom and cellular tyrosinase activities in vitro. Resorcinol and lawsone can also downregulate the protein levels of tyrosinase and microphthalmia-associated transcription factor (MITF in B16-F10 cells. Thus, we suggest that frequent use of hair dyes may have the risk of reducing natural melanin production in hair follicles. Moreover, resorcinol and lawsone may also be used as hypopigmenting agents to food, agricultural and cosmetic industry in the future.

  4. Summary of pilot-scale activities with resorcinol ion exchange resin

    International Nuclear Information System (INIS)

    Cicero, C.A.; Bickford, D.F.; Sargent, T.N.; Andrews, M.K.; Bibler, J.P.; Bibler, N.E.; Jantzen, C.M.

    1995-01-01

    The Mixed Waste Focus Area (MWFA) of the Department of Energy (DOE) is currently investigating vitrification technology for treatment of low level mixed wastes (LLMW). They have chartered the Savannah River Technology Center (SRTC) to study vitrification of the wastes through an Office of Technology Development (OTD) Technical Task Plan (TTP). SRTC's efforts have included crucible-scale studies and pilot scale testing on simulated LLMW sludges, resins, soils, and other solid wastes. Results from the crucible-scale studies have been used as the basis for the pilot-scale demonstrations. As part of the fiscal year (FY) 1995 activities, SRTC performed crucible-scale studies with organic resins. This waste stream was selected because of the large number of DOE sites, as well as commercial industries, that use resins for treatment of liquid wastes. Pilot-scale studies were to be completed in FY 1995, but could not be due to a reduction in funding. Instead, a compilation of pilot-scale tests with organic resins performed under the guidance of SRTC was provided in this report. The studies which will be discussed used a resorcinol- formaldehyde resin loaded with non-radioactive cesium, which was fed with simulated wastewater treatment sludge feed. The first study was performed at the SRTC in the mini-melter, 1/100th scale of the Defense Waste Processing Facility (DWPF) melter, and also involved limited crucible-scale studies to determine the resin loading obtainable. The other study was performed at the DOE/Industrial Center for Vitrification Research (Center) and involved both crucible and pilot-scale testing in the Stir-Melter stirred-melter. Both studies were successful in vitrifying the resin in simulated radioactive sludge and glass additive feeds

  5. Mixture Design Approach on the Physical Properties of Lignin-Resorcinol-Formaldehyde Xerogels

    Directory of Open Access Journals (Sweden)

    Chris D. Castro

    2015-01-01

    Full Text Available Organic xerogels were functionalized by incorporating sugarcane bagasse lignin from soda pulping black liquor, not used so far in this materials, with the aim of introducing new functional groups on traditional gels that could improve its adsorptive capacity. Two mixing designs were applied to identify the reactive combinations that allow a well gel formation and to adjust models that predict physical properties. The designs study five components: resorcinol (R, 0.04–0.3, lignin (L, 0.004–0.14, formaldehyde (F, 0.08–0.17, water (W, 0.45–0.8, and NaOH (C, 0.0003–0.0035. The first experimental design was an extreme vertices design and its results showed shrinkage between 4.3 and 59.7 and a bulk density from 0.54 to 1.3; a mass ratio LR/F near 1.5 was required for gel formation. In the second design a D-Optimal was used to achieve better adjusted coefficients and incorporate the largest possible amount of lignin in the gels. Bulk density varies from 0.42 to 0.9, shrinkage varies from 3.42 to 25.35, and specific surface area reaches values of 451.86 m2/g with 13% lignin and 270 m2/g with 27% lignin. High catalyst content improves lignin dissolution and increase shrinkage and bulk density of xerogels and bulk density. Lignin contributes to reducing shrinkage and specific surface area due to his compact and rigid structure.

  6. Exogenous ether lipids predominantly target mitochondria.

    Directory of Open Access Journals (Sweden)

    Lars Kuerschner

    Full Text Available Ether lipids are ubiquitous constituents of cellular membranes with no discrete cell biological function assigned yet. Using fluorescent polyene-ether lipids we analyzed their intracellular distribution in living cells by microscopy. Mitochondria and the endoplasmic reticulum accumulated high amounts of ether-phosphatidylcholine and ether-phosphatidylethanolamine. Both lipids were specifically labeled using the corresponding lyso-ether lipids, which we established as supreme precursors for lipid tagging. Polyfosine, a fluorescent analogue of the anti-neoplastic ether lipid edelfosine, accumulated to mitochondria and induced morphological changes and cellular apoptosis. These data indicate that edelfosine could exert its pro-apoptotic power by targeting and damaging mitochondria and thereby inducing cellular apoptosis. In general, this study implies an important role of mitochondria in ether lipid metabolism and intracellular ether lipid trafficking.

  7. In vitro biological characterization of a novel, synthetic diaryl pyrazole resorcinol class of heat shock protein 90 inhibitors.

    Science.gov (United States)

    Sharp, Swee Y; Boxall, Kathy; Rowlands, Martin; Prodromou, Chrisostomos; Roe, S Mark; Maloney, Alison; Powers, Marissa; Clarke, Paul A; Box, Gary; Sanderson, Sharon; Patterson, Lisa; Matthews, Thomas P; Cheung, Kwai-Ming J; Ball, Karen; Hayes, Angela; Raynaud, Florence; Marais, Richard; Pearl, Laurence; Eccles, Sue; Aherne, Wynne; McDonald, Edward; Workman, Paul

    2007-03-01

    The molecular chaperone heat shock protein 90 (HSP90) has emerged as an exciting molecular target. Derivatives of the natural product geldanamycin, such as 17-allylamino-17-demethoxy-geldanamycin (17-AAG), were the first HSP90 ATPase inhibitors to enter clinical trial. Synthetic small-molecule HSP90 inhibitors have potential advantages. Here, we describe the biological properties of the lead compound of a new class of 3,4-diaryl pyrazole resorcinol HSP90 inhibitor (CCT018159), which we identified by high-throughput screening. CCT018159 inhibited human HSP90beta with comparable potency to 17-AAG and with similar ATP-competitive kinetics. X-ray crystallographic structures of the NH(2)-terminal domain of yeast Hsp90 complexed with CCT018159 or its analogues showed binding properties similar to radicicol. The mean cellular GI(50) value of CCT018159 across a panel of human cancer cell lines, including melanoma, was 5.3 mumol/L. Unlike 17-AAG, the in vitro antitumor activity of the pyrazole resorcinol analogues is independent of NQO1/DT-diaphorase and P-glycoprotein expression. The molecular signature of HSP90 inhibition, comprising increased expression of HSP72 protein and depletion of ERBB2, CDK4, C-RAF, and mutant B-RAF, was shown by Western blotting and quantified by time-resolved fluorescent-Cellisa in human cancer cell lines treated with CCT018159. CCT018159 caused cell cytostasis associated with a G(1) arrest and induced apoptosis. CCT018159 also inhibited key endothelial and tumor cell functions implicated in invasion and angiogenesis. Overall, we have shown that diaryl pyrazole resorcinols exhibited similar cellular properties to 17-AAG with potential advantages (e.g., aqueous solubility, independence from NQO1 and P-glycoprotein). These compounds form the basis for further structure-based optimization to identify more potent inhibitors suitable for clinical development.

  8. Preliminary flowsheet: Ion exchange for separation of cesium from Hanford tank waste using resorcinol-formaldehyde resin

    International Nuclear Information System (INIS)

    Penwell, D.L.

    1994-01-01

    This preliminary flowsheet document describes an ion exchange process which uses resorcinol-formaldehyde (R-F) resin to remove cesium from Hanford tank waste. The flowsheet describes one possible equipment configuration, and contains mass balances based on that configuration with feeds of Neutralized Current Acid Waste, and Double Shell Slurry Feed. The flowsheet also discusses process alternatives, unresolved issues, and development needs associated with the ion exchange process. It is expected that this flowsheet will evolve as open issues are resolved and progress is made on development needs. This is part of the Tank Waste Remediation Program at Hanford. 26 refs, 6 figs, 25 tabs

  9. The simple ethers of glycerin

    International Nuclear Information System (INIS)

    Kimsanov, B.Kh.; Karimov, M.B.

    1998-01-01

    From glycerin derivatives the considerable interest is present simple ethers because many of them are biological active and found wide practical using as an effect drugs, inters for thin organic synthesis, vehicle for injections, regulators of plants growth, reagents, components for perfumery-cosmetic goods and etc

  10. Hydraulic Permeability of Resorcinol-Formaldehyde Ion-Exchange Resin - Effects of Oxygen Uptake and Radiation

    International Nuclear Information System (INIS)

    Taylor, Paul Allen

    2009-01-01

    An ion-exchange process, using spherical resorcinol-formaldehyde (RF) resin is the baseline process for removing cesium from the dissolved salt solution in the high-level waste tanks at the U.S. Department of Energy's (DOE) Hanford site in Washington State. The RF resin is also being evaluated for use in the proposed Small Column Ion Exchange (SCIX) system, which is an alternative treatment option at DOE's Savannah River Site (SRS)in South Carolina. Testing at ORNL will determine the impact of radiation exposure and oxygen uptake by the RF resin on the hydraulic permeability of the resin. Samples of the resin will be removed periodically to measure physical properties (bead size and compressibility) and cesium capacity. The proposed full-scale treatment system at Hanford, the Waste Treatment Plant (WTP), will use an ion-exchange column containing nominally 680 gal of resin, which will treat 30 gpm of waste solution. The ion-exchange column is designed for a typical pressure drop of 6 psig, with a maximum of 9.7 psig. The lab-scale column is 3-in. clear PVC pipe and is prototypic of the proposed Hanford column. The fluid velocity in the lab-scale test will be much higher than for the full-scale column, in order to generate the maximum pressure drop expected in that column (9.7 psig). The frictional drag from this high velocity will produce similar forces on the resin in the lab-scale column as would be expected at the bottom of the full-scale column. The chemical changes in the resin caused by radiation exposure and oxygen uptake are expected to cause physical changes in the resin that could reduce the bed porosity and reduce the hydraulic permeability of the resin bed. These changes will be monitored by measuring the pressure drop through the lab-scale column and by measuring the physical properties of samples of the resin. The test loop with the lab-scale column is currently being fabricated, and operation will start by late May. Testing will be completed by the

  11. The Nitrite-Scavenging Properties of Catechol, Resorcinol, and Hydroquinone: A Comparative Study on Their Nitration and Nitrosation Reactions.

    Science.gov (United States)

    Lu, Yunhao; Dong, Yanzuo; Li, Xueli; He, Qiang

    2016-10-14

    The nitration and nitrosation reactions of catechol, resorcinol, and hydroquinone (0.05 mmol/L) with sodium nitrite (0.05 mmol/L) at pH 3 and 37 °C were studied by using liquid chromatography and mass spectrometry (LC-MS) and atom charge analysis, which was aimed to provide chemical insight into the nitrite-scavenging behavior of polyphenols. The 3 benzenediols showed different mechanisms to scavenge nitrite due to their differences in hydroxyl position. Catechol was nitrated with 1 NO 2 group at the hydroxyl oxygen, and resorcinol was nitrosated with 2 NO groups at the C 2 and C 4 (or C 6 ) positions of the benzene ring. Hydroquinone could scavenge nitrite through both nitration and nitrosation mechanisms. The nitrated hydroquinone had 1 NO 2 group at the hydroxyl oxygen in the molecule, while the nitrosated 1 containing 2 NO groups at the benzene ring might have 3 structure probabilities. The results may provide a structure-activity understanding on the nitrite-scavenging property of polyphenols, so as to promote their application in the food industry for the removal of possibly toxic nitrites found in many vegetables and often in processed meat products. © 2016 Institute of Food Technologists®.

  12. Poly (ether ether ketone) membranes for fuel cells

    International Nuclear Information System (INIS)

    Marrero, Jacqueline C.; Gomes, Ailton de S.; Filho, Jose C.D.; Hui, Wang S.; Oliveira, Vivianna S. de

    2015-01-01

    Polymeric membranes were developed using a SPEEK polymer matrix (sulphonated poly (ether ether ketone)), containing hygroscopic particles of zirconia (Zr) (incorporated by sol-gel method), for use as electrolyte membranes in fuel cells. SPEEK with different sulfonation degrees were used: 63 and 86%. The thermal analysis (TGA and DSC) was carried out to characterize the membranes and electrochemical impedance spectroscopy (EIS) was carried out to evaluating the proton conductivity of the membranes. Additional analysis were underway in order to characterize these membranes, which include: X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) in order to evaluate the influence of zirconia and sulfonation degree on the properties of the membranes. (author)

  13. Hydrogen storage by functionalised Poly(ether ether ketone)

    Energy Technology Data Exchange (ETDEWEB)

    Pedicini, R.; Giacoppo, G.; Carbone, A.; Passalacqua, E. [CNR-ITAE, Messina (Italy). Inst. for Advanced Energy Technologies

    2010-07-01

    In this work a functionalised polymer was studied as potential material for hydrogen storage in solid state. A Poly(ether ether ketone) (PEEK) matrix was modified by a manganese oxide in situ formation. Here we report the functionalisation process and the preliminary results on hydrogen storage capability of the synthesised polymer. The polymer was characterized by Scanning Electron Microscopy, X-ray diffraction, Transmission Electron Microscopy and Gravimetric Hydrogen Adsorption measurements. In the functionalised PEEK, morphological changes occur as a function of oxide precursor concentration and reaction time. Promising results by gravimetric measurements were obtained with a hydrogen sorption of 0.24%wt/wt at 50 C and 60 bar, moreover, reversibility hydrogen adsorption and desorption in a wide range of both temperature and pressure was confirmed. (orig.)

  14. Biaxial deformation behaviour of poly-ether-ether-ketone

    Science.gov (United States)

    Turner, Josh; Menary, Gary; Martin, Peter

    2018-05-01

    The biaxial tensile properties of thin poly-ether-ether-ketone (PEEK) films are presented. Investigation into the biaxial mechanical behaviour of PEEK films will provide a preliminary insight into the anticipated stress/strain response, and potential suitability, to the possible fabrication of thin walled parts through stretch blow moulding and thermoforming processes - with the multi-axial state of strain imposed onto the heated thermoplastic sheet representative of the expected strain history experienced during these material forming processes. Following identification of the prospective forming temperature window, the biaxial mechanical behaviour of the material is characterized under differing modes of deformation, at a nominal strain rate of 1 s-1. The temperature dependence is outlined within - with an appreciable increase in flow behaviour correlated with specimen temperature exceeding its glass transition temperature (Tg).

  15. Sulfonated polyphenyl ether by electropolymerization

    International Nuclear Information System (INIS)

    Hou Hongying; Vacandio, Florence; Di Vona, Maria Luisa; Knauth, Philippe

    2012-01-01

    Highlights: ► Sulfonated polyphenyl ether was for the first time electropolymerized. ► This technique allows the economical preparation of ionomeric membranes for electrochemical energy technologies. ► The mechanism of electropolymerization was discussed in detail. - Abstract: Electropolymerization of sulfonated phenol was for the first time achieved and studied by cyclic voltammetry (CV) and chronoamperometry on stainless steel substrates. The obtained sulfonated polyphenyl ether was characterized in terms of impedance spectroscopy, nuclear magnetic resonance (NMR), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD) and Fourier-Transform Infrared (FTIR) spectroscopy. Dense films of micrometer thickness can be obtained; the proton conductivity is about 3 mS/cm at room temperature.

  16. INFLUÊNCIA DO CATALISADOR EM SOLUÇÕES POLIMÉRICAS PARA O PREPARO DE GÉIS ORGÂNICOS DE RESORCINOL-FORMALDEÍDO

    Directory of Open Access Journals (Sweden)

    Thalita S. Taiariol

    2015-11-01

    Full Text Available Resorcinol-formaldehyde (RF organic gels have been extensively used to produce carbon aerogels. The organic gel synthesis parameters greatly affect the structure of the resulting aerogel. In this study, the influence of the catalyst quantity on the polymeric solution sol-gel process was investigated. Sodium carbonate was used as a basic catalyst. RF gels were synthesized with a resorcinol to formaldehyde molar ratio of 0.5, a resorcinol to catalyst (R/C molar ratio equal to 50 or 300, and a resorcinol to solvent ratio of 0.1 g mL-1. The sol-gel process was evaluated in situ by Fourier transform infrared spectroscopy using a universal attenuated total reflectance sensor and measurements of the kinematic viscosity. The techniques showed the evolution of the sol-gel process, and the results showed that the lower catalyst quantity induced a higher gel point, with a lower viscosity at the gel point. Differential scanning calorimetry was used to investigate the thermal behavior of the RF dried gel, and results showed that the exothermic event related to the curing process was shifted to higher temperatures for solutions containing higher R/C ratios.

  17. Actinide/crown ether chemistry

    International Nuclear Information System (INIS)

    Benning, M.M.

    1988-01-01

    A structural survey of actinide/crown ether compounds was conducted in order to investigate the solid state chemistry of these complexes. Several parameters - the metal size, crown type, counterion, solvent systems and reaction and crystallization conditions - were varied to correlate their importance in complexation. Under atmospheric conditions, two types of complexes were isolated, those containing only hydrogen-bonded crown interactions and instances where the crown interacts directly with the metal center. In both cases, water seems to play a very important role. When coordinated to the metal, water molecules exhibit the necessary donor properties required for the formation of hydrogen-bonded contacts. The water molecules also provide fierce competition with the crown ethers for metal-binding sites and in most cases prohibit the formation of complexes in which direct metal-ligand association exists. The results of this study indicate that direct interaction between the metal atoms and the crown ethers, in the presence of water, can only occur with polyether conformations which limit the steric replusions within the metal coordination sphere

  18. ADSORCIÓN DE RESORCINOL DESDE SOLUCIÓN ACUOSA SOBRE CARBÓN ACTIVADO. RELACIÓN ISOTERMAS DE ADSORCIÓN Y ENTALPÍA DE INMERSIÓN RESORCINOL

    OpenAIRE

    Blanco, Diego A; Giraldo, Liliana; JuanC, Moreno

    2008-01-01

    Se estudia la adsorción de resorcinol sobre carbones activados modificados, obtenidos a partir de un carbón activado granular comercial CarbochemTM –PS30, (CAG), por medio de tratamiento químico con HNO37M, carbón activado oxidado (CAO) y tratamiento térmico bajo flujo de H2, carbón activado reducido (CAR). Se analiza la influencia del pH de la solución, la reducción y oxidación de la superficie del carbón y se determina la entalpía de inmersión de los carbones activados en soluciones acuosas...

  19. PILOT-SCALE HYDRAULIC TESTING OF RESORCINOL FORMALDEHYDE ION EXCHANGE RESIN

    International Nuclear Information System (INIS)

    Adamson, D

    2007-01-01

    Savannah River National Laboratory (SRNL) performed pilot-scale hydraulic/chemical testing of spherical resorcinol formaldehyde (RF) ion exchange (IX) resin for the River Protection Project Hanford Tank Waste Treatment and Immobilization Plant (WTP) Project. The RF resin cycle testing was conducted in two pilot-scale IX columns, 1/4 and 1/2 scale. A total of twenty-three hydraulic/chemical cycles were successfully completed on the spherical RF resin. Seven of the cycles were completed in the 12-inch IX Column and sixteen cycles were completed in the 24-inch IX Column. Hydraulic testing showed that the permeability of the RF resin remained essentially constant, with no observed trend in the reduction of the permeability as the number of cycles increased. The permeability during the pilot-scale testing was 2 1/2 times better than the design requirements of the WTP full-scale system. The permeability of the resin bed was uniform with respect to changes in bed depth. Upflow Regeneration and Simulant Introduction in the IX columns revealed another RF resin benefit; negligible radial pressures to the column walls from the swelling of resin beads. In downflow of the Regeneration and Simulant Introduction steps, the resin bed particles pack tightly together and produce higher hydraulic pressures than that found in upflow. Also, upflow Simulant Introduction produced an ideal level bed for the twenty cycles completed using upflow Simulant Introduction. Conversely, the three cycles conducted using downflow Simulant Introduction produced an uneven bed surface with erosion around the thermowells. The RF resin bed in both columns showed no tendency to form fissures or pack more densely as the number of cycles increased. Particle size measurements of the RF resin showed no indication of particle size change (for a given chemical) with cycles and essentially no fines formation. Micrographs comparing representative bead samples before and after testing indicated no change in bead

  20. PILOT-SCALE HYDRAULIC TESTING OF RESORCINOL FORMALDEHYDE ION EXCHANGE RESIN

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, D

    2007-01-09

    Savannah River National Laboratory (SRNL) performed pilot-scale hydraulic/chemical testing of spherical resorcinol formaldehyde (RF) ion exchange (IX) resin for the River Protection Project Hanford Tank Waste Treatment & Immobilization Plant (WTP) Project. The RF resin cycle testing was conducted in two pilot-scale IX columns, 1/4 and 1/2 scale. A total of twenty-three hydraulic/chemical cycles were successfully completed on the spherical RF resin. Seven of the cycles were completed in the 12-inch IX Column and sixteen cycles were completed in the 24-inch IX Column. Hydraulic testing showed that the permeability of the RF resin remained essentially constant, with no observed trend in the reduction of the permeability as the number of cycles increased. The permeability during the pilot-scale testing was 2 1/2 times better than the design requirements of the WTP full-scale system. The permeability of the resin bed was uniform with respect to changes in bed depth. Upflow Regeneration and Simulant Introduction in the IX columns revealed another RF resin benefit; negligible radial pressures to the column walls from the swelling of resin beads. In downflow of the Regeneration and Simulant Introduction steps, the resin bed particles pack tightly together and produce higher hydraulic pressures than that found in upflow. Also, upflow Simulant Introduction produced an ideal level bed for the twenty cycles completed using upflow Simulant Introduction. Conversely, the three cycles conducted using downflow Simulant Introduction produced an uneven bed surface with erosion around the thermowells. The RF resin bed in both columns showed no tendency to form fissures or pack more densely as the number of cycles increased. Particle size measurements of the RF resin showed no indication of particle size change (for a given chemical) with cycles and essentially no fines formation. Micrographs comparing representative bead samples before and after testing indicated no change in bead

  1. PILOT-SCALE HYDRAULIC TESTING OF RESORCINOL FORMALDEHYDE ION EXCHANGE RESIN

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, D

    2006-11-08

    Savannah River National Laboratory (SRNL) performed pilot-scale hydraulic/chemical testing of spherical resorcinol formaldehyde (RF) ion exchange (IX) resin for the River Protection Project-Hanford Tank Waste Treatment & Immobilization Plant (WTP) Project. The RF resin cycle testing was conducted in two pilot-scale IX columns, 1/4 and 1/2 scale. A total of twenty-three hydraulic/chemical cycles were successfully completed on the spherical RF resin. Seven of the cycles were completed in the 12 inch IX Column and sixteen cycles were completed in the 24 inch IX Column. Hydraulic testing showed that the permeability of the RF resin remained essentially constant, with no observed trend in the reduction of the permeability as the number of cycles increased. The permeability during the pilot-scale testing was 2 1/2 times better than the design requirements of the WTP full-scale system. The permeability of the resin bed was uniform with respect to changes in bed depth. Upflow Regeneration and Simulant Introduction in the IX columns revealed another RF resin benefit; negligible radial pressures to the column walls from the swelling of resin beads. In downflow of the Regeneration and Simulant Introduction steps, the resin bed particles pack tightly together and produce higher hydraulic pressures than that found in upflow. Also, upflow Simulant Introduction produced an ideal level bed for the twenty cycles completed using upflow Simulant Introduction. Conversely, the three cycles conducted using downflow Simulant Introduction produced an uneven bed surface with erosion around the thermowells. The RF resin bed in both columns showed no tendency to form fissures or pack more densely as the number of cycles increased. Particle size measurements of the RF resin showed no indication of particle size change (for a given chemical) with cycles and essentially no fines formation. Micrographs comparing representative bead samples before and after testing indicated no change in bead

  2. A neutron powder diffraction study of deuterated α-resorcinol: a test of profile refinement using TLS constraints

    International Nuclear Information System (INIS)

    Bacon, G.E.; Lisher, E.J.

    1979-01-01

    Constrained TL, TLX and TLS refinements have been used, with the powder-profile method, in the analysis of accurate neutron powder data for deuterated α-resorcinol at room temperature. There is good agreement between the translational and librational parameters derived from the TL refinement and those obtained from an equivalent analysis of accurate single-crystal neutron measurements. The fine details of the benzene ring are lost in the powder analysis, but the molecular orientation and the OH bond angles are in good agreement with the single-crystal values. No significant improvement could be found in the powder fit by applying the full TLS theory and, therefore, the approximate TLX model appears to be adequate for powder data. (Auth.)

  3. Adsorción de resorcinol desde solución acuosa sobre carbón activado

    OpenAIRE

    BLANCO, DIEGO A.; GIRALDO, LILIANA; MORENO, JUAN C.

    2009-01-01

    Se analiza el comportamiento de adsorción de resorcinol, un fenol monohidroxilado débilmente ácido a 298 K sobre carbón activado, estudiando la influencia del pH de la solución en el proceso de adsorción y la influencia de la reducción de la superficie del carbón. Para ello se utiliza un carbón activado de origen lignocelulósico y un material que resulta de la reducción del mismo. La interacción sólido­solución se caracteriza por el análisis de sus isotermas de adsorción a 298 K a valore...

  4. Synthesis of resorcinol resin as a polymer adsorbent, and study of its usability in uranium sorption process

    International Nuclear Information System (INIS)

    Aslani, M. A. A.; Yusan, S.; Goek, C.; Akyil, S.; Aytas, S.

    2009-01-01

    Uranium is one of the most important elements in nuclear fuel technology. In order to obtain purified of this element at uranium mining and processing the use of synthetic resins is significant at column and/or batch process. The synthesis of resorcinol resin polymer was carried out with a modified microwave oven instead of the conventional heater due to the some advantage properties such as very rapid reaction, rapid bulk heat, short reaction duration and high yield etc. To characterization of synthesized resin FT-IR, TG-DTA and SEM techniques were used. In order to obtain the optimum uranium adsorption conditions the effective sorption parameters such as solution pH, uranium concentration, reaction time and temperature were investigated.

  5. Critical properties of some aliphatic symmetrical ethers

    International Nuclear Information System (INIS)

    Nikitin, Eugene D.; Popov, Alexander P.; Bogatishcheva, Nataliya S.

    2014-01-01

    Highlights: • Critical properties of simple aliphatic ethers were measured. • The ethers decompose at near-critical temperatures. • Pulse-heating method with short residence times was used. -- Abstract: The critical temperatures T c and the critical pressures p c of dihexyl, dioctyl, and didecyl ethers have been measured. According to the measurements, the coordinates of the critical points are T c = (665 ± 7) K, p c = (1.44 ± 0.04) MPa for dihexyl ether, T c = (723 ± 7) K, p c = (1.19 ± 0.04) MPa for dioctyl ether, and T c = (768 ± 8) K, p c = (1.03 ± 0.03) MPa for didecyl ether. All the ethers studied degrade chemically at near-critical temperatures. A pulse-heating method applicable to measuring the critical properties of thermally unstable compounds has been used. The times from the beginning of a heating pulse to the moment of reaching the critical temperature were from 0.06 to 0.46 ms. The short residence times provide little decomposition of the substances in the course of the experiments. The critical properties of the ethers investigated in this work have been discussed together with those of methyl to butyl ethers. The experimental critical constants of the ethers have been compared with those estimated by the group-contribution methods of Wilson and Jasperson and Marrero and Gani. The Wilson/Jasperson method provides a better estimation of the critical temperatures and pressures of simple aliphatic ethers in comparison with the Marrero/Gani method if reliable normal boiling temperatures are used in the method of Wilson and Jasperson

  6. Comparison of Properties among Dendritic and Hyperbranched Poly(ether ether ketones and Linear Poly(ether ketones

    Directory of Open Access Journals (Sweden)

    Atsushi Morikawa

    2016-02-01

    Full Text Available Poly(ether ether ketone dendrimers and hyperbranched polymers were prepared from 3,5-dimethoxy-4′-(4-fluorobenzoyldiphenyl ether and 3,5-dihydroxy-4′-(4-fluorobenzoyldiphenyl ether through aromatic nucleophilic substitution reactions. 1-(tert-Butyldimethylsiloxy-3,5-bis(4-fluorobenzoylbenzene was polycondensed with bisphenols, followed by cleavage of the protective group to form linear poly(ether ketones having the same hydroxyl groups in the side chains as the chain ends of the dendrimer and hyperbranched polymers. Their properties, such as solubilities, reduced viscosities, and thermal properties, were compared with one another. Similar comparisons were also carried out among the corresponding methoxy group polymers, and the size of the molecules was shown to affect the properties.

  7. Numerical analysis of spray characteristics of dimethyl ether and diethyl ether fuel

    International Nuclear Information System (INIS)

    Mohan, Balaji; Yang, Wenming; Yu, Wenbin; Tay, Kun Lin

    2017-01-01

    Highlights: • Thermo-physical properties of liquid DME and DEE are reported. • Ether fuels tend to cavitate higher compared to that of diesel fuel. • Spray tip penetration and SMD are found to be lesser for ether fuels. • Ether fuels shows excellent atomization behavior. - Abstract: In this work, the spray characteristics of ether fuels such as dimethyl ether (DME) and diethyl ether (DEE) have been numerically investigated using KIVA-4 CFD code. A new hybrid spray model developed by coupling the standard KHRT model to cavitation sub model was used. The detailed thermo-physical properties of ether fuels have been predicted and validated with experimental results available from literature. The cavitation inception inside the injector nozzle hole has been studied for ether fuels in comparison with diesel fuel. It was found that ether fuels cavitates higher compared to that of conventional diesel fuel because of its low viscosity. The spray tip penetration of diesel fuel was longer than that of ether fuels due to high viscosity and density of diesel fuel. Ether fuels characterized by low Ohnesorge number and high Reynolds number showed better atomization behavior compared to that of the diesel fuel.

  8. Unitary information ether and its possible applications

    International Nuclear Information System (INIS)

    Horodecki, R.

    1991-01-01

    The idea of information ether as the unitary information field is developed. It rests on the assumption that the notion of information is a fundamental category in the description of reality and that it can be defined independently from the notion of probability itself. It is shown that the information ether provides a deterministic background for the nonlinear wave hypothesis and quantum cybernetics. (orig.)

  9. Polyether ether ketone film. Polyether ether ketone film

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, S. (Sumitomo Chemical Co. Ltd., Tokyo (Japan))

    1990-07-05

    The characteristics and the film making process of polyether ether ketone (PEEK) resin, and the characteristics and the applications of PEEK film, are described. PEEK is aromatic polyketone with super thermal resistance. Though it is a crystalline polymer of which the crystallinity is controlled to 48% in a highest degree, it has also amorphous property, thus it shows unique property. The characteristics of PEEK resin are found in thermal resistance, incombusti-bility, transparency, chemical resistance, light resistance and radiation resistance. As for the film making process, casting method by T-die is generally adopted. The general properties of PEEK film are excellent in high thermal resistance, good electrical properties, chemical resistance, hydrolysis resistance, radiation resistance and imcombusti-bility. In the application of PEEK film, new development is expected in following fields; a high performance composite, flexible print substrate with high thermal resistance, insulating tape with thermal resistance, and a general film in the nuclear energy industry. 5 figs., 5 tabs.

  10. Solution of Azelaic Acid (20%), Resorcinol (10%) and Phytic Acid (6%) Versus Glycolic Acid (50%) Peeling Agent in the Treatment of Female Patients with Facial Melasma.

    Science.gov (United States)

    Faghihi, Gita; Taheri, Azam; Shahmoradi, Zabihollah; Nilforoushzadeh, Mohammad Ali

    2017-01-01

    Melasma, a common acquired disorder of hyperpigmentation, especially in women, is often resistant to therapy. This study was aimed to evaluate the efficacy and safety of azelaic acid, resorcinol and phytic acid solution in chemical peeling of melasma in comparison to 50% glycolic acid. This clinical trial was performed, on 42 female patients with bilateral melasma. Severity of melasma was assessed by melasma area and severity index (MASI). Combination of (20% azelaic acid + 10% resorcinol + 6% phytic acid) was used as a new peeling agent on the right side of the face and 50% glycolic acid on the left side every 2 weeks for 6 times. Follow-up was carried out for 3 months after the last session. Any decrease in MASI score and unwanted complications following peeling were evaluated and compared during the trial. Patients showed marked improvement as calculated with MASI score before and after treatment in both sides of the face. The efficacy of combination formula (azelaic acid, resorcinol and phytic acid) was similar to glycolic acid, but with fewer complications. There was no statistically difference in improvement between two groups ( P > 0.05). However, the patient's discomfort following procedures was significantly lower with azelaic acid, resorcinol and phytic compared with the glycolic acid peels ( P < 0.05) and there was the same duration in the beginning of the therapeutic response in both groups. Results showed that triple-combination was found to be an effective and safe peeling agent in the treatment of melasma and it was as effective as 50% glycolic acid peel.

  11. Solution of Azelaic Acid (20%, Resorcinol (10% and Phytic Acid (6% Versus Glycolic Acid (50% Peeling Agent in the Treatment of Female Patients with Facial Melasma

    Directory of Open Access Journals (Sweden)

    Gita Faghihi

    2017-01-01

    Full Text Available Background: Melasma, a common acquired disorder of hyperpigmentation, especially in women, is often resistant to therapy. This study was aimed to evaluate the efficacy and safety of azelaic acid, resorcinol and phytic acid solution in chemical peeling of melasma in comparison to 50% glycolic acid. Materials and Methods: This clinical trial was performed, on 42 female patients with bilateral melasma. Severity of melasma was assessed by melasma area and severity index (MASI. Combination of (20% azelaic acid + 10% resorcinol + 6% phytic acid was used as a new peeling agent on the right side of the face and 50% glycolic acid on the left side every 2 weeks for 6 times. Follow-up was carried out for 3 months after the last session. Any decrease in MASI score and unwanted complications following peeling were evaluated and compared during the trial. Results: Patients showed marked improvement as calculated with MASI score before and after treatment in both sides of the face. The efficacy of combination formula (azelaic acid, resorcinol and phytic acid was similar to glycolic acid, but with fewer complications. There was no statistically difference in improvement between two groups (P > 0.05. However, the patient's discomfort following procedures was significantly lower with azelaic acid, resorcinol and phytic compared with the glycolic acid peels (P < 0.05 and there was the same duration in the beginning of the therapeutic response in both groups. Conclusion: Results showed that triple-combination was found to be an effective and safe peeling agent in the treatment of melasma and it was as effective as 50% glycolic acid peel.

  12. A glassy carbon electrode modified with cerium phosphate nanotubes for the simultaneous determination of hydroquinone, catechol and resorcinol.

    Science.gov (United States)

    Li, Zhen; Yue, Yuhua; Hao, Yanjun; Feng, Shun; Zhou, Xianli

    2018-03-12

    A nafion film containing cerium phosphate nanotubes was pasted onto a glassy carbon electrode (GCE) to obtain a sensor for hydroquinone (HQ). The morphologies and components of the coating were characterized by transmission electron microscopy, scanning electron microscopy and energy-dispersive spectroscopy. Cyclic voltammetry and differential pulse voltammetry (DPV) showed the specific surface of the electrode to be significantly increased and the electron transfer rate to be accelerated. The modified GCE was applied to the determination of hydroquinone (HQ) via DPV. The oxidation current increases linearly in the 0.23 μM to 16 mM HQ concentration range which is as wide as five orders of magnitude. The limit of detection is 0.12 μM (based on a signal-to-noise ratio of 3), and the sensitivity is 1.41 μA·μM -1  cm -2 . The method was further applied to the simultaneous determination of HQ, catechol and resorcinol. The potentials for the three species are well separated (20, 134, and 572 mV vs SCE). Average recoveries from (spiked) real water samples are between 95.2 and 107.0%, with relative standard deviations of 0.9~2.7% (for n = 3) at three spiking levels. The method was validated by independent assays using HPLC. Graphical abstract ᅟ.

  13. Activity relationships for aromatic crown ethers

    International Nuclear Information System (INIS)

    Wilson, Mark James

    1998-01-01

    This thesis involves an investigation of aromatic crown ethers and a study of their binding constants for alkali metals. The study was motivated by the current needs of the semiconductor industry to improve the scavenging of mobile ions from fabricated circuits. A number of aromatic crown ethers have been sulphonated in an attempt to improve their water solubility and cation binding activity. These materials have been extensively studied and their binding activity determined. In collaboration with a molecular modelling study, the effect of ionisable sulphonate groups on the macrocycles' behaviour has been investigated. The broader issue of the effect of substituents in aromatic crown ethers has also been studied with the preparation of a wide range of substituted crown ethers. The cation binding activity of these materials has been found to bear a simple relationship to the electron withdrawing nature of the aromatic substituents. This relationship can be accurately monitored using electronic charge densities from molecular modelling and this rational has been applied to the study of proton ionisable and lariating crown ethers. The incorporation of crown ethers into polyamic acid and polyimide frameworks has also been investigated, where the resulting materials have been found to exhibit unusual cation binding and uptake properties. These results imply that the combination of the crown ethers' macrocycle and adjacent carboxylic acid residues, from the polyamic acids, are conducive to effective cationic binding. NMR measurements, in conjunction with molecular modelling, have been used to explore the geometry changes encountered as the crown ether goes from it's uncomplexed to its complexed state. The energy requirement for these geometry changes has subsequently been used to examine the cation selectivity of these materials. The electronic charge changes associated with the complexation have also been investigated and correlated with the theoretical results. (author)

  14. Exogenous ether lipids predominantly target mitochondria

    DEFF Research Database (Denmark)

    Kuerschner, Lars; Richter, Doris; Hannibal-Bach, Hans Kristian

    2012-01-01

    Ether lipids are ubiquitous constituents of cellular membranes with no discrete cell biological function assigned yet. Using fluorescent polyene-ether lipids we analyzed their intracellular distribution in living cells by microscopy. Mitochondria and the endoplasmic reticulum accumulated high......, accumulated to mitochondria and induced morphological changes and cellular apoptosis. These data indicate that edelfosine could exert its pro-apoptotic power by targeting and damaging mitochondria and thereby inducing cellular apoptosis. In general, this study implies an important role of mitochondria...

  15. Novel crosslinked membranes based on sulfonated poly(ether ether ketone) for direct methanol fuel cells.

    Science.gov (United States)

    Zhu, Yuanqin; Zieren, Shelley; Manthiram, Arumugam

    2011-07-14

    Novel covalently crosslinked membranes based on sulfonated poly(ether ether ketone) and carboxylated polysulfone exhibit much lower methanol crossover and better performance in direct methanol fuel cells at 65 °C in 1 and 2 M methanol solutions compared to Nafion 115 membranes.

  16. Optical anisotropy, molecular orientations, and internal stresses in thin sulfonated poly(ether ether ketone) films

    NARCIS (Netherlands)

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

    2015-01-01

    The thickness, the refractive index, and the optical anisotropy of thin sulfonated poly(ether ether ketone) films, prepared by spin-coating or solvent deposition, have been investigated with spectroscopic ellipsometry. For not too high polymer concentrations (≤5 wt%) and not too low spin speeds

  17. Optical anisotropy, molecular orientations, and internal stresses in thin sulfonated poly(ether ether ketone) films

    NARCIS (Netherlands)

    Koziara, Beata; Nijmeijer, Dorothea C.; Benes, Nieck Edwin

    2015-01-01

    The thickness, the refractive index, and the optical anisotropy of thin sulfonated poly(ether ether ketone) films, prepared by spin-coating or solvent deposition, have been investigated with spectroscopic ellipsometry. For not too high polymer concentrations (B5 wt%) and not too low spin speeds

  18. Thermal stability of sulfonated Poly(Ether Ether Ketone) films : on the role of Protodesulfonation

    NARCIS (Netherlands)

    Koziara, B.T.; Kappert, E.J.; Ogieglo, W.; Nijmeijer, Kitty; Hempenius, M.A.; Benes, N.E.

    Thin film and bulk, sulfonated poly(ether ether ketone) (SPEEK) have been subjected to a thermal treatment at 160–250 °C for up to 15 h. Exposing the films to 160 °C already causes partial desulfonation, and heating to temperatures exceeding 200 °C results in increased conjugation in the material,

  19. Dissociative Photoionization of Diethyl Ether.

    Science.gov (United States)

    Voronova, Krisztina; Mozaffari Easter, Chrissa M; Covert, Kyle J; Bodi, Andras; Hemberger, Patrick; Sztáray, Bálint

    2015-10-29

    The dissociative photoionization of internal energy selected diethyl ether ions was investigated by imaging photoelectron photoion coincidence spectroscopy. In a large, 5 eV energy range Et2O(+) cations decay by two parallel and three sequential dissociative photoionization channels, which can be modeled well using statistical theory. The 0 K appearance energies of the CH3CHOCH2CH3(+) (H-loss, m/z = 73) and CH3CH2O═CH2(+) (methyl-loss, m/z = 59) fragment ions were determined to be 10.419 ± 0.015 and 10.484 ± 0.008 eV, respectively. The reemergence of the hydrogen-loss ion above 11 eV is attributed to transition-state (TS) switching, in which the second, outer TS is rate-determining at high internal energies. At 11.81 ± 0.05 eV, a secondary fragment of the CH3CHOCH2CH3(+) (m/z = 73) ion, protonated acetaldehyde, CH3CH═OH(+) (m/z = 45) appears. On the basis of the known thermochemical onset of this fragment, a reverse barrier of 325 meV was found. Two more sequential dissociation reactions were examined, namely, ethylene and formaldehyde losses from the methyl-loss daughter ion. The 0 K appearance energies of 11.85 ± 0.07 and 12.20 ± 0.08 eV, respectively, indicate no reverse barrier in these processes. The statistical model of the dissociative photoionization can also be used to predict the fractional ion abundances in threshold photoionization at large temperatures, which could be of use in, for example, combustion diagnostics.

  20. Development Of An Approach To Modeling Loading And Elution Of Spherical Resorcinol Formaldehyde Ion-Exchange Resin

    International Nuclear Information System (INIS)

    Aleman, S.; Hamm, L.; Smith, F.

    2011-01-01

    The current strategy for removal of cesium from the Hanford waste stream is ion-exchange using spherical Resorcinol-Formaldehyde (sRF) resin. The original resin of choice was granular SuperLig 644 resin and during testing of this resin several operational issues were identified. For example, the granular material had a high angle of internal friction resulting in fragmentation of resin particles along its edges during cycling and adverse hydraulic performance. Efforts to replace SuperLig 644 were undertaken and one candidate was the granular Resorcinol-Formaldehyde (RF) resin where experience with this cation exchanger dates back to the late 1940's. To minimize hydraulic concerns a spherical version of RF was developed and several different chemically produced batches were created. The 5E-370/641 batch of sRF was selected and for the last decade numerous studies have been performed (e.g., batch contact tests, column loading and elution tests). The Waste Treatment Plant (WTP) flowsheet shows that the aqueous phase waste stream will have a wide range of ionic concentrations (e.g., during the loading step 0-3 M free OH, 5+ M Na, 0-1 M K, 0-3 M NO 3 ). Several steps are required in the ion-exchange process to achieve the required Cs separation factors: loading, displacement, washing, elution, and regeneration. The sRF resin will be operated over a wide range in pH (i.e., pH of 12-14 during the loading step and pH of 0.01-1 during the elution step). During some of these steps very high levels of counter-ions and co-ions will be present within the aqueous phase. Alternative process feeds are under consideration as well (e.g., sodium levels as high as 8 M and column operation up to 45 C during loading, reduced and recycled HNO 3 during elution). In order to model the performance of sRF resin through an entire ion-exchange cycle, a more robust isotherm model is required. To achieve this more robust isotherm model requires knowledge of the numbers and kinds of fixed

  1. DEVELOPMENT OF AN APPROACH TO MODELING LOADING AND ELUTION OF SPHERICAL RESORCINOL FORMALDEHYDE ION-EXCHANGE RESIN

    Energy Technology Data Exchange (ETDEWEB)

    Aleman, S.; Hamm, L.; Smith, F.

    2011-10-03

    The current strategy for removal of cesium from the Hanford waste stream is ion-exchange using spherical Resorcinol-Formaldehyde (sRF) resin. The original resin of choice was granular SuperLig 644 resin and during testing of this resin several operational issues were identified. For example, the granular material had a high angle of internal friction resulting in fragmentation of resin particles along its edges during cycling and adverse hydraulic performance. Efforts to replace SuperLig 644 were undertaken and one candidate was the granular Resorcinol-Formaldehyde (RF) resin where experience with this cation exchanger dates back to the late 1940's. To minimize hydraulic concerns a spherical version of RF was developed and several different chemically produced batches were created. The 5E-370/641 batch of sRF was selected and for the last decade numerous studies have been performed (e.g., batch contact tests, column loading and elution tests). The Waste Treatment Plant (WTP) flowsheet shows that the aqueous phase waste stream will have a wide range of ionic concentrations (e.g., during the loading step 0-3 M free OH, 5+ M Na, 0-1 M K, 0-3 M NO{sub 3}). Several steps are required in the ion-exchange process to achieve the required Cs separation factors: loading, displacement, washing, elution, and regeneration. The sRF resin will be operated over a wide range in pH (i.e., pH of 12-14 during the loading step and pH of 0.01-1 during the elution step). During some of these steps very high levels of counter-ions and co-ions will be present within the aqueous phase. Alternative process feeds are under consideration as well (e.g., sodium levels as high as 8 M and column operation up to 45 C during loading, reduced and recycled HNO{sub 3} during elution). In order to model the performance of sRF resin through an entire ion-exchange cycle, a more robust isotherm model is required. To achieve this more robust isotherm model requires knowledge of the numbers and kinds of

  2. Development of a nanostructured lipid carrier formulation for increasing photo-stability and water solubility of Phenylethyl Resorcinol

    International Nuclear Information System (INIS)

    Fan, Hengfeng; Liu, Guoqing; Huang, Yiqing; Li, Yan; Xia, Qiang

    2014-01-01

    The Phenylethyl Resorcinol loaded nanostructured lipid carrier (PR-NLC) was developed by hot high-pressure homogenization method. The freshly prepared PR-NLC showed a spherical morphology under transmission electron microscope, and the particle size was 218.3 ± 9.2 nm. The value of the zeta potential of PR-NLC decreased from −30.2 ± 1.9 mV to −64.9 ± 1.3 mV when the dilution times reach 10. The loading amount of PR encapsulated in NLC was 2.94 ± 0.03%, and the average entrapment efficiencies of PR-NLC determinated by size exclusion chromatography and ultrafiltration were 90.2 ± 0.6% and 98.3 ± 0.3%. Lyophilization was proved feasible for the storage of NLC dispersion. Fourier transform infrared spectra (FTIR) was exploited to investigate the possible drug–lipid complex formation. Advancements in water solubility of PR were demonstrated by NLC using a contact angle measurement. The hemolysis percentage of the NLC was less than 1.3% in a certain range of concentration. In 90 days’ storage, 88.6 ± 2.8% of PR remained unchanged in PR-NLC under natural daylight. In vitro release studies revealed a sustained drug release, and in vitro penetration studies showed an increase of retention amount of PR in the skin, when applying PR-NLC. Therefore, the NLC might be a potential delivery vehicle in cosmetic dermal products.

  3. Synthesis of morphology-controlled carbon hollow particles by carbonization of resorcinol-formaldehyde precursor microspheres and applications in lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Haijiao, E-mail: seaboyfang@163.com [Modern Manufacture Engineering Center, Heilongjiang Institute of Science and Technology, 150027 (China); Xu Huifang, E-mail: xuhf@hit.edu.cn [School of Chemical Engineering and Technology, Harbin Institute of Technology, 150001 (China); Zhao Can [Modern Manufacture Engineering Center, Heilongjiang Institute of Science and Technology, 150027 (China)

    2012-03-15

    Highlights: Black-Right-Pointing-Pointer Resorcinol-formaldehyde hollow particles could be obtained by inverse suspension method. Black-Right-Pointing-Pointer The morphologies of RF carbon precursor particles could be controlled by adjusting the pH values of the RF precursor. Black-Right-Pointing-Pointer The prepared carbon hollow particles, which derived from resorcinol-formaldehyde, exhibited microporous properties. Black-Right-Pointing-Pointer The RF carbon microcapsules displayed excellent power property and cycle durability. - Abstract: The morphology-controlled carbon hollow particles, derived from resorcinol-formaldehyde (RF) particles, were prepared by using an (oil phase) O/(water phase) W/(oil phase) O inverse-emulsion system which was formed by adding RF precursor (water phase) to n-hexane (oil phase) with Span-80 as surfactant and the following carbonization. This simple method led to the formation of various morphologies of RF carbon precursor particles such as hollow spheres, bowl-like hollow structures, microcapsules, or solid microspheres by adjusting the pH values of the RF precursor. The synthesized carbon particles exhibited porous characters with the surface area of 659 m{sup 2} g{sup -1} and the total pore volume of 0.44 cm{sup 3} g{sup -1}. Additionally, the electrochemical behavior of the typical RF carbon particles in lithium-ion batteries revealed that the RF carbon microcapsules displayed a high initial discharge capacity of 1059 mAh g{sup -1} and stabilized at about 330 mAh g{sup -1}, indicating its excellent power property and cycle durability.

  4. Complex Formation in a Liquid-Liquid Extraction System Containing Cobalt(II), 4-(2-Pyridylazo)resorcinol, and Nitron

    OpenAIRE

    Racheva, Petya Vassileva; Gavazov, Kiril Blazhev; Lekova, Vanya Dimitrova; Dimitrov, Atanas Nikolov

    2013-01-01

    Complex formation and liquid-liquid extraction were studied in a system containing cobalt(II), 4-(2-pyridylazo)resorcinol (PAR), 1,4-diphenyl-3-(phenylamino)-1H-1,2,4-triazole (Nitron, Nt), water, and chloroform. The effect of some experimental parameters (pH, shaking time, concentration of PAR, and concentration of Nt) was systematically investigated, and the optimum conditions for cobalt extraction as an ion-association complex, (NtH+)[Co3+(PAR)2], were found. The following key equilibrium ...

  5. Injection characteristics of dimethyl ether

    Energy Technology Data Exchange (ETDEWEB)

    Glensvig, M.

    1996-09-01

    Dimethyl ether (DME) has proved to be a new ultra-clean alternative fuel for diesel engines. Engine tests have shown considerably lower NO{sub x} emissions, no particle emissions and lower noise compared to that obtained from normal diesel engine operation. DME also has demonstrated favorable response to Exhaust Gas Recirculation (EGR). The purpose of this investigation was to achieve a better understanding of the fundamental spray behavior of DME. Fundamental spray behaviour was characterized by fuel spray penetration and angle, atomization and droplet size and evaporation. The influence of fuel characteristics, nozzle geometry and ambient pressure on the DME and diesel spray behavior was investigated. Fuel was injected into an unheated injection chamber with a ambient pressure of 15 bar and 25 bar, respectively, giving a simplified simulation of the environment in an operating engine. Two nozzles were studied: a single hole nozzle and a pintle nozzle. A conventional fuel injection system was used for both nozzles. Injection parameters of RPM, throttle position, fuel line length and chamber environment were held constant for both nozzles. The sprays were visualized using schlieren and high speed photography. Results show that the general appearance of the DME spray is similar to that of diesel spray. The core of the DME spray seems less dense and the spray tip less sharp compared to diesel spray, indicating smaller droplets with a lower momentum in the core of the DME spray. Schlieren film shows that with both DME and diesel fuel, the spray tip only consists of liquid and that evaporation occurs after a brief time interval. Penetration of DME is about one third that of diesel using the pintle nozzle. Also, the spray angle is considerably larger for the DME spray compared to the diesel spray. A comparatively smaller difference in penetration is observed using the hole nozzle. Differences in penetration for the hole nozzle are within the limit of the penetration

  6. Radiation-induced transformations of cellulose ethers

    International Nuclear Information System (INIS)

    Nud'ga, L.A.; Petropavlovskii, G.S.; Plisko, E.A.; Isakova, O.V.; Ershov, B.G.

    1988-01-01

    The purpose of this investigation was to study the transformation which take place under the action of γ-radiation in a number of cellulose ethers containing both saturated (carboxymethyl, hydroxyethyl) and unsaturated (allyl, methacryloyl) groups. Irradiation was carried out on a 60 Co unit in air at 77 and 300 K; the dose rate was 37 and 50 kGy/h respectively. The EPR spectra of γ-irradiated hydroxyethyl- and allylhydroxyethylcelluloses are identical. Under the action of γ-radiation extensive changes took place in cellulose ethers which are exhibited in degradation or the formation of three-dimensional structures and are accompanied by a change in the functional composition. The efficiency in the formation of radicals and their localization are determined by the nature and number of substituents in the cellulose ethers

  7. On new physical reality (on ψ-ether)

    International Nuclear Information System (INIS)

    Isaev, P.S.

    2002-01-01

    It is shown that there exists a new physical reality - the ψ-ether. All the achievements of quantum mechanics and quantum field theory are due to the fact that both the theories include the influence of ψ-ether on the physical processes occurring in the Universe. Physics of the XX century was first of all the physics of ψ-ether

  8. Study of transport properties and conduction mechanism of pure and composite resorcinol formaldehyde aerogel doped with Co-ferrite

    International Nuclear Information System (INIS)

    Attia, S.M.; Sharshar, T.; Abd-Elwahed, A.R.; Tawfik, A.

    2013-01-01

    Highlights: • A novel composite RF aerogels with Co-ferrite were prepared by sol–gel process. • RF aerogels exhibit a semiconducting behavior. • The dielectric constant of RF aerogel is very low (4 times as that of air) and can be controlled by adding Co-ferrite. • Large overlapping polaron (OLP) was found to be the preferred conduction mechanism in these materials. -- Abstract: A series of resorcinol formaldehyde aerogels (RF aerogels) composite with nanoparticles of CoFe 2 O 4 have been prepared by sol–gel method. Four samples of pure RF aerogels were prepared at different concentrations of Na 2 CO 3 as catalyst (0.02, 0.025, 0.03, and 0.04 wt.%) and four samples of composite RF aerogels were prepared at different concentration of doped CoFe 2 O 4 (0.075, 0.1, 0.125, and 0.15 wt.%; Na 2 CO 3 concentration = 0.03 wt.%). DC electrical conductivity as a function of temperature was studied in the temperature range 25 °C–200 °C for all samples. AC electrical conductivity and dielectric properties were determined using RLC Bridge in the frequency range 100 Hz–1 MHz at different temperature (25–200 °C). The pore size of the samples was determined using positron annihilation lifetime spectroscopy (PALS). RF aerogels are found to exhibit a semiconducting behavior and characterized by two transition temperatures T 1 and T 2 . Also σ DC increases with increase of Co-ferrite contents. Pure RF aerogels posses a very low dielectric constant, where the lowest value of ε′ is ∼4 times as that of air. ε′ decreases with increase of frequency, and increases with increase of temperature. Large overlapping polaron (OLP) is found to be the preferred conduction mechanism in these materials. The results of PALS show that there are two types of pore size in these samples; the first ranges from 1.9 to 2.5 nm, while the second ranges from 3.2 to 5.3 nm

  9. Incidence of flare-ups and evaluation of quality after retreatment of resorcinol-formaldehyde resin ("Russian Red Cement") endodontic therapy.

    Science.gov (United States)

    Gound, Tom G; Marx, David; Schwandt, Nathan A

    2003-10-01

    The purpose of this retrospective study was to evaluate the quality of treatment and incidence of flare-ups when teeth with resorcinol-formaldehyde resin are retreated in a postgraduate endodontic clinic. Fifty-eight cases were included in this study. Obturated and unfilled canal space was measured on radiographs. Forty-eight percent of the total canal space was filled before retreatment; 90% was filled after retreatment. After retreatment, obturations were rated as optimal in 59%, improved in 33%, unchanged in 6%, and worse in 2%. Seven patients (12%) had postretreatment flare-ups. Data were statistically analyzed using the Cochran-Armitage Test for Discrete Variables. No statistical difference in the incidence of flare-ups was found in teeth that before treatment had more than half the canal space filled compared to teeth with less than half, cases with pre-existing periradicular radiolucencies compared to cases with normal periradicular appearance, symptomatic cases compared to asymptomatic cases, or cases with optimal fillings after retreatment compared to less than optimal cases. It was concluded that teeth with resorcinol-formaldehyde fillings might be retreated with a good prognosis for improving the radiographic quality, but a higher than normal incidence of flare-ups may occur.

  10. Children's exposure to polybrominated diphenyl ethers.

    NARCIS (Netherlands)

    Zuurbier, M.; Leijs, M.; Schoeters, G.; Tusscher, G. Ten; Koppe, J.G.

    2006-01-01

    Background: Polybrominated biphenyl ethers (PBDEs), a class of brominated flame retardants, are frequently used in consumer products. PBDEs levels in environmental and human samples have increased in recent decades. Children are exposed to PBDEs through diet, mainly through fish, meat and milk.

  11. Polybrominated diphenyl ethers and novel flame retardants

    DEFF Research Database (Denmark)

    Frederiksen, Marie; Vorkamp, Katrin; Nielsen, Jesper Bo

    ,4,6-tribromophenyl ether (TBP-DBPE) and dechlorane plus (DDC-CO) have been detected in the same dust samples previously analysed for PBDEs and are currently being analysed in the corresponding human milk samples. [1] Stapleon H.M., Eagle S., Sjödin A., Webster T.F. (2012). Serum PBDEs in a North Carolina Toddler...

  12. [Visualisation methods for etheric formative forces].

    Science.gov (United States)

    Burkhard, B; Kittel, R

    2009-09-01

    Rudolf Steiner, the founder of anthroposophy, suggested the development of visualisation methods for "etheric formative forces". The essential methods, their "spiritual scientific" basis and indications are described and their claims critically tested. The methods are not validated, the key criteria for diagnostic tests (reproducibility, sensitivity, specifity) are not given.

  13. Microwave sintering of poly-ether-ether-ketone (PEEK) based coatings deposited on metallic substrate

    International Nuclear Information System (INIS)

    Zhang, G.; Leparoux, S.; Liao, H.; Coddet, C.

    2006-01-01

    In this paper, the feasibility of microwave (MW) sintering PEEK (poly-ether-ether-ketone) based coatings was investigated. Three coatings were studied: pure PEEK, micron-SiC and nano-SiC particles filled (wt.10%) PEEK coatings. The results indicate that, for the two composite coatings, the SiC particles distributed in the polymer matrix, as a good MW susceptor, could be heated preferentially by MW radiation. Consequently, the polymer matrix was heated by these particles

  14. Selective crystallization of cations with crown ethers

    International Nuclear Information System (INIS)

    Heffels, Dennis Egidius

    2014-01-01

    The aim of this work was to study the selectivity and preferences of the incorporation of differently sized cations in the cavities of various crown ethers and the characterization of the resulting compounds. The coordination preferences of crown ethers with different cavities have long been known, and the impact of other effects on the structure formation have increasingly become the focus of attention. In this work a comparative overview of the coordination preferences depending on various factors was undertaken. The focus was mainly on the variation of the cavity of the crown ether in the presence of differently sized cations. In addition, the effects of the solvent and differently coordinating anions have been investigated. Within the framework of this work, basic coordination preferences could be detected with rare earth nitrates, which are affected particularly by the choice of the solvent. The formation of different types of structures could be controlled by varying the conditions such that the incorporation of the cation in the cavity of the crown ether was influenced and the formation of a particular type of structure can be influenced partly by the choice of solvent. In this case no direct preferences for the incorporation into the cavity of the crown ether in relation to the cation size were observed for rare earth cations. However, the coordination of the crown ether leads in each case - for lanthanides - to rather high coordination numbers. A total of five new rare earth complexes and two structural variants could be observed with crown ethers. In the study of the selectivity of the incorporation into the cavity, known structures were also reproduced and further structures were characterized but the crystal structures not entirely solved. With the use of monovalent cations such as potassium, lithium or silver a total of nine new compounds could be synthesized, while no clear preferences for the incorporation of certain cations were detected. The

  15. Ion-Selective Ionic Polymer Metal Composite (IPMC) actuator based on crown ether containing sulfonated Poly(Arylene Ether Ketone)

    NARCIS (Netherlands)

    Tas, S.; Zoetebier, B.; Sukas, O.S.; Bayraktar, M.; Hempenius, M.; Vancso, G.J.; Nijmeijer, K.

    2017-01-01

    This study introduces the concept of ion selective actuation in polymer metal composite actuators, employing crown ether bearing aromatic polyether materials. For this purpose, sulfonated poly(arylene ether ketone) (SPAEK) and crown ether containing SPAEK with molar masses suitable for membrane

  16. Process for making propenyl ethers and photopolymerizable compositions containing them

    Science.gov (United States)

    Crivello, James V.

    1996-01-01

    Propenyl ether monomers of formula V A(OCH.dbd.CHCH.sub.3).sub.n wherein n is an integer from one to six and A is selected from cyclic ethers, polyether and alkanes are disclosed. The monomers are readily polymerized in the presence of cationic photoinitiators, when exposed to actinic radiation, to form poly(propenyl ethers) that are useful for coatings, sealants, varnishes and adhesives. Compositions for preparing polymeric coatings comprising the compounds of formula V together with particular cationic photoinitiators are also disclosed, as are processes for making the monomers from allyl halides and readily available alcohols. The process involves rearranging the resulting allyl ethers to propenyl ethers.

  17. Radiation-induced cationic curing of vinyl ethers

    International Nuclear Information System (INIS)

    Lapin, S.C.

    1992-01-01

    Recently there has been an increasing interest in nonacrylate radiation-curable coatings. Vinyl ethers are particularly reactive under cationic polymerization reaction conditions. The high efficiency of the photoacid initiators combined with the high reactivity of vinyl ether monomers makes this a potentially very useful system. This chapter discusses the preparation of vinyl ethers, introduces vinyl ether-functional monomers and oligomers, describes radiation-induced cationic polymerization of vinyl ethers, and discusses various coating systems. Throughout the chapter, an emphasis is placed on radiation-curable coating applications. 64 refs., 5 figs., 11 tabs

  18. Hardness and wear properties of boron-implanted poly(ether-ether-ketone) and poly-ether-imide

    International Nuclear Information System (INIS)

    Lee Youngchul; Lee, E.H.; Mansur, L.K.

    1992-01-01

    The effects of boron beam irradiation on the hardness, friction, and wear of polymer surfaces were investigated. Typical high-performance thermoplastics, poly(ether-ether-ketone) (PEEK) and a poly-ether-imide (Ultem) were studied after 200 keV boron ion beam treatment at ambient temperature to doses of 2.3x10 14 , 6.8x10 14 , and 2.2x10 15 ions cm -2 . The hardnesses of pristine and boron-implanted materials were characterized by a conventional Knoop method and a load-depth sensing nanoindentation technique. Both measurements showed a significant increase in hardness with increasing dose. The increase in hardness was also found to depend on the penetration depth of the diamond indenter. Wear and friction properties were characterized by a reciprocating sliding friction tester with an SAE 52100 high-carbon, chrome steel ball at 0.5 and 1 N normal loads. Wear and frictional properties varied in a complex fashion with polymer type and dose, but not much with normal load. A substantial reduction in friction coefficient was observed for PEEK at the highest dose but no reduction was observed for Ultem. The wear damage was substantially reduced at the highest dose for both Ultem and PEEK. For the system studied, the highest dose, 2.2x10 15 ions cm -2 , appears to be optimum in improving wear resistance for both PEEK and Ultem. (orig.)

  19. Radiolytic decomposition of 4-bromodiphenyl ether

    International Nuclear Information System (INIS)

    Tang Liang; Xu Gang; Wu Wenjing; Shi Wenyan; Liu Ning; Bai Yulei; Wu Minghong

    2010-01-01

    Polybrominated diphenyl ethers (PBDEs) spread widely in the environment are mainly removed by photochemical and anaerobic microbial degradation. In this paper, the decomposition of 4-bromodiphenyl ether (BDE -3), the PBDEs homologues, is investigated by electron beam irradiation of its ethanol/water solution (reduction system) and acetonitrile/water solution (oxidation system). The radiolytic products were determined by GC coupled with electron capture detector, and the reaction rate constant of e sol - in the reduction system was measured at 2.7 x 10 10 L · mol -1 · s -1 by pulsed radiolysis. The results show that the BDE-3 concentration affects strongly the decomposition ratio in the alkali solution, and the reduction system has a higher BDE-3 decomposition rate than the oxidation system. This indicates that the BDE-3 was reduced by effectively capturing e sol - in radiolytic process. (authors)

  20. Model for Photodegradation of Polybrominated Diphenyl Ethers

    Czech Academy of Sciences Publication Activity Database

    Veselý, M.; Vajglová, Zuzana; Kotas, Petr; Křišťál, Jiří; Ponec, Robert; Jiřičný, Vladimír

    2015-01-01

    Roč. 22, č. 7 (2015), s. 4949-4963 ISSN 0944-1344 R&D Projects: GA ČR GA104/09/0880; GA ČR(CZ) GAP105/12/0664 Institutional support: RVO:67985858 ; RVO:67179843 Keywords : polybrominated diphenyl ethers * photodegradation model * quantum chemical calculation Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.760, year: 2015

  1. Promoting environmentally sound management of polybrominated diphenyl ethers in Asia.

    Science.gov (United States)

    Li, Jinhui; Zhao, Nana; Liu, Xue; Wu, Xiaoyang

    2014-06-01

    Polybrominated diphenyl ethers with persistent organic pollutant properties are required to be controlled by the Stockholm Convention. Recently, polybrominated diphenyl ether contamination has become widespread in Asia, mainly because of the disposal and recycling processes of polybrominated diphenyl ether-containing wastes. The management status, production, usage, import/export, treatment, and disposal, as well as implementation deficiencies for the environmentally sound management of polybrominated diphenyl ethers and polybrominated diphenyl ether-containing materials in ten Asian countries were investigated and assessed in this study. This information could help the participating countries implement the Stockholm Convention and could promote the regional environmentally sound management of polybrominated diphenyl ether-containing articles and products. The results obtained were as follows. (1) Most of the countries studied lacked environmental policies and regulations, or even standards of polybrominated diphenyl ether pollution management and emission control actions. Accurate data on the consumption and importation of polybrominated diphenyl ether-containing materials, however, were not available for all the participating countries. In addition, there were no special treatment or disposal systems for polybrominated diphenyl ether-containing materials, or emission-cutting measures for the treatment of waste in these countries, owing to the lack of sufficient funding or technologies. (2) The improper dismantling of e-waste is a major source of polybrominated diphenyl ether emissions in these countries. (3) Proper e-waste management could result in a breakthrough in the environmentally sound management of this major polybrominated diphenyl ether-containing material flow, and could significantly reduce polybrominated diphenyl ether emissions. Finally, based on the study results, this article puts forward some recommendations for improving the environmentally

  2. Nikola Tesla, the Ether and his Telautomaton

    Science.gov (United States)

    Milar, Kendall

    2014-03-01

    In the nineteenth century physicists' understanding of the ether changed dramatically. New developments in thermodynamics, energy physics, and electricity and magnetism dictated new properties of the ether. These have traditionally been examined from the perspective of the scientists re-conceptualizing the ether. However Nikola Tesla, a prolific inventor and writer, presents a different picture of nineteenth century physics. Alongside the displays that showcased his inventions he presented alternative interpretations of physical, physiological and even psychical research. This is particularly evident in his telautomaton, a radio remote controlled boat. This invention and Tesla's descriptions of it showcase some of his novel interpretations of physical theories. He offered a perspective on nineteenth century physics that focused on practical application instead of experiment. Sometimes the understanding of physical theories that Tesla reached was counterproductive to his own inventive work; other times he offered new insights. Tesla's utilitarian interpretation of physical theories suggests a more scientifically curious and invested inventor than previously described and a connection between the scientific and inventive communities.

  3. Thermal Stability of Sulfonated Poly(Ether Ether Ketone) Films: on the Role of Protodesulfonation

    OpenAIRE

    Koziara, Beata; Kappert, Emiel; Ogieglo, Wojciech; Nijmeijer, Dorothea C.; Hempenius, Mark A.; Benes, Nieck Edwin

    2016-01-01

    Thin film and bulk, sulfonated poly(ether ether ketone) (SPEEK) have been subjected to a thermal treatment at 160–250 °C for up to 15 h. Exposing the films to 160 °C already causes partial desulfonation, and heating to temperatures exceeding 200 °C results in increased conjugation in the material, most likely via a slight cross-linking by H-substitution. It is well-known that the sulfonate proton plays a major role in the desulfonation reactions, and exchanging the protons with other cations ...

  4. Preliminary Investigation of Poly-Ether-Ether-Ketone Based on Fused Deposition Modeling for Medical Applications

    Directory of Open Access Journals (Sweden)

    Feng Zhao

    2018-02-01

    Full Text Available Poly-ether-ether-ketone (PEEK fabricated by fused deposition modeling for medical applications was evaluated in terms of mechanical strength and in vitro cytotoxicity in this study. Orthogonal experiments were firstly designed to investigate the significant factors on tensile strength. Nozzle temperature, platform temperature, and the filament diameter were tightly controlled for improved mechanical strength performance. These sensitive parameters affected the interlayer bonding and solid condition in the samples. Fourier transform infrared (FTIR spectrometry analysis was secondly conducted to compare the functional groups in PEEK granules, filaments, and printed parts. In vitro cytotoxicity test was carried out at last, and no toxic substances were introduced during the printing process.

  5. All solid supercapacitor based on polyaniline and crosslinked sulfonated poly[ether ether ketone

    International Nuclear Information System (INIS)

    Sivaraman, P.; Kushwaha, R.K.; Shashidhara, K.; Hande, V.R.; Thakur, A.P.; Samui, A.B.; Khandpekar, M.M.

    2010-01-01

    All solid supercapacitor based on polyaniline (PANI) and crosslinked sulfonated poly[ether ether ketone] (XSPEEK,) is reported in this paper. The crosslinker used for sulfonated poly[ether ether ketone] (SPEEK) is 1,4-bis(hydroxymethyl) benzene. The XSPEEK is used as both solid electrolyte and separator membrane. Supercapacitors are fabricated using various PANI/XSPEEK weight ratios. These are characterized by cyclic voltammetry and galvanostatic charge-discharge studies. The supercapacitor with PANI/XSPEEK weight ratio 1:0.5, exhibit a specific capacitance of 480 F g -1 of PANI. To the best of authors' knowledge, the value reported here is the highest for a supercapacitor based on a proton conducting solid polymer electrolyte and PANI. Detailed electrochemical impedance spectroscopy analysis is carried out. The analysis shows that the complex capacitance of the supercapacitor depends on the XSPEEK content. The time constant (t 0 ), derived from the imaginary part of complex capacitance decreases with increase in the XSPEEK content in the supercapacitor. Cycle life characteristics of the supercapacitor show a decrease in specific capacitance during initial cycles and get stabilized during later cycles.

  6. Lithiated and sulphonated poly(ether ether ketone) solid state electrolyte films for supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, K.-F.; Su, S.-H., E-mail: minimono42@gmail.com

    2013-10-01

    Poly(ether ether ketone) (PEEK) films have been synthesised and used as solid-state electrolytes for supercapacitors. In order to increase their ion conductivity, the PEEK films were sulphonated by sulphuric acid, and various amounts of LiClO{sub 4} were added. The solid-state electrolyte films were characterised by Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and thermogravimetric analysis. The ionic conductivities of the electrolyte films were analysed by performing electrochemical impedance spectroscopy. The obtained electrolyte films can be sandwiched or directly coated on activated carbon electrodes to form solid-state supercapacitors. The electrochemical characteristics of these supercapacitors were investigated by performing cyclic voltammetry and charge–discharge tests. Under an optimal content of LiClO{sub 4}, the supercapacitor can provide a capacitance as high as 190 F/g. After 1000 cycles, the supercapacitors show almost no capacitance fading, indicating high stability of the solid-state electrolyte films. - Highlights: • Poly(ether ether ketone) (PEEK) films have been used as solid-state electrolytes. • LiClO4 addition can efficiently improve the ionic conductivity. • Supercapacitors using PEEK electrolyte films deliver high capacitance.

  7. Silane Cross-Linked Sulfonted Poly(Ether Ketone/Ether Benzimidazoles for Fuel Cell Applications

    Directory of Open Access Journals (Sweden)

    Zilu Yao

    2017-11-01

    Full Text Available γ-(2,3-epoxypropoxy propyltrimethoxysilane (KH-560 was incorporated in various proportions into side-chain-type sulfonated poly(ether ketone/ether benzimidazole (SPEKEBI as a crosslinker, to make membranes with high ion exchange capacities and excellent performance for direct methanol fuel cells (DMFCs. Systematical measurements including Fourier transform infrared (FT-IR, scanning electron microscopy-energy-dispersive and X-ray photoelectron spectroscopy (XPS proved the complete disappearance of epoxy groups in KH-560 and the existence of Si in the membranes. The resulting membranes showed increased mechanical strength and thermal stability compared to the unmodified sulfonated poly(ether ketone/ether benzimidazole membrane in appropriate doping amount. Meanwhile, the methanol permeability has decreased, leading to the increase of relative selectivities of SPEKEBI-x-SiO2 membranes. Furthermore, the H2/O2 cell performance of SPEKEBI-2.5-SiO2 membrane showed a much higher peak power density compared with the pure SPEKEBI memrbrane.

  8. Lithiated and sulphonated poly(ether ether ketone) solid state electrolyte films for supercapacitors

    International Nuclear Information System (INIS)

    Chiu, K.-F.; Su, S.-H.

    2013-01-01

    Poly(ether ether ketone) (PEEK) films have been synthesised and used as solid-state electrolytes for supercapacitors. In order to increase their ion conductivity, the PEEK films were sulphonated by sulphuric acid, and various amounts of LiClO 4 were added. The solid-state electrolyte films were characterised by Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and thermogravimetric analysis. The ionic conductivities of the electrolyte films were analysed by performing electrochemical impedance spectroscopy. The obtained electrolyte films can be sandwiched or directly coated on activated carbon electrodes to form solid-state supercapacitors. The electrochemical characteristics of these supercapacitors were investigated by performing cyclic voltammetry and charge–discharge tests. Under an optimal content of LiClO 4 , the supercapacitor can provide a capacitance as high as 190 F/g. After 1000 cycles, the supercapacitors show almost no capacitance fading, indicating high stability of the solid-state electrolyte films. - Highlights: • Poly(ether ether ketone) (PEEK) films have been used as solid-state electrolytes. • LiClO4 addition can efficiently improve the ionic conductivity. • Supercapacitors using PEEK electrolyte films deliver high capacitance

  9. The failure of poly (ether ether ketone) in high speed contacts

    Science.gov (United States)

    Briscoe, B. J.; Stuart, B. H.; Sebastian, S.; Tweedale, P. J.

    1993-04-01

    The paper describes an experimental study, with an associated analysis incorporating supplementary data, of the anti-boundary lubricating action of an alkane-aliphatic carboxylic acid lubricant system in a poly (ether ether ketone)-mild steel contact. The experiments involve progressively increasing the load in a contact formed between a polymer plate and a rotating steel shaft and estimating the frictional work dissipated. Scuffing is identified when a rapid increase in frictional work is noted at a characteristic normal load. It is shown that the additive induces premature scuffing. Subsidiary data is provided using Raman spectroscopy and hardness probes, and confirms that certain additives such as decanoic acid and dodecylamine will induce surface plasticization in poly (ether ether ketone). The trends in the frictional data have been interpreted using the adhesive model of friction in conjunction with temperature-dependent interfacial theology and bulk mechanical property data. It is proposed that the scuffing process is induced prematurely as a consequence of excessive additive-induced subsurface plasticization. Restricted surface plasticization in this system provides an enhanced self-lubricating capacity.

  10. An Exposure Assessment of Polybrominated Diphenyl Ethers ...

    Science.gov (United States)

    EPA announced the availability of the final report, An Exposure Assessment of Polybrominated Diphenyl Ethers. This report provides a comprehensive assessment of the exposure of Americans to this class of persistent organic pollutants. Individual chapters in this document address: the production, use, and lifecycle of PBDEs; environmental fate; environmental levels; and human exposure. This final report addresses the exposure assessment needs identified in the OPBDE Workgroup project plan. It provides a comprehensive assessment of the exposure of Americans to this class of persistent organic pollutants. Individual chapters in this document address: the production, use, and lifecycle of PBDEs; environmental fate; environmental levels; and human exposure.

  11. Copper Promoted Synthesis of Diaryl Ethers

    OpenAIRE

    Ghosh, Rajshekhar; Samuelson, Ashoka G

    2004-01-01

    An efficient protocol using copper based reagents for the coupling of aryl halides with phenols to generate diaryl ethers is described. Acopper( I) complex, [ Cu( CH3CN) (4)] ClO4, or the readily available copper( II) source, CuCO3 . Cu( OH) (2) . H2O ( in combination with potassium phosphate), can be used. Aryl halides and phenols with different steric and electronic demands have been used to assess the efficiency of the procedure. The latter source of copper gives better yields under all co...

  12. Gamma-radiolysis of benzosubstituted crown ethers

    International Nuclear Information System (INIS)

    Grigor'ev, E.I.; Nesterov, S.V.; Mikhalitsyna, O.V.; Trakhtenberg, L.I.; Myasoedova, T.G.

    1992-01-01

    The products of gamma-radiolysis of benzosubstituted crown ethers, which are distiguished by the size of polyether ring, and alkylsubstituted DB18C6 are studied by the methods of ESR and mass-spectrometry. A mechanism of the radiolysis of the radiolysis of the studied compounds in the solid phase is proposed. It is shown that the prinicple radiolysis process is the rupture of C-O bond resulting in the stabilization of H atoms from group -CH 2 - of polyether ring is realized with a lower probability

  13. Biodegradability of fuel-ethers in environment; Biodegradabilite des ethers-carburants dans l'environnement

    Energy Technology Data Exchange (ETDEWEB)

    Fayolle-Guichard, F

    2005-04-01

    Fuel ethers (methyl tert-butyl ether or MTBE, ethyl tert-butyl ether or ETBE and tert-amyl methyl ether or TAME have been used as gasoline additives since about twenty years in order to meet the requirements for the octane index and to limit the polluting emission in exhaust pipe gas (unburnt hydrocarbons and carbon monoxide). The high water solubility and the poor biodegradability of these compounds make them pollutants frequently encountered in aquifers. The present manuscript summarizes the knowledge concerning the biodegradability of fuel ethers obtained both at IFP and during collaborations with the Pasteur Institute (Paris), the Biotechnology Research Institute (Montreal, Canada) and the Center for Environmental Biotechnology (University of Tennessee, USA). Rhodococcus ruber IFP 2001 and Mycobacterium austroafricanum IFP 2012, two microorganisms isolated at IFP for their ability to grow, respectively, on ETBE and MTBE, were studied in order to determine the intermediates produced during MTBE and ETBE biodegradation and the enzymes required for each biodegradation step, thus allowing us to propose MTBE and ETBE catabolic pathways. A proteomic approach, from the protein induced during the degradation of ETBE or MTBE to the genes encoding these different enzymes, was carried out. The isolation of such genes is required:1) to use them for help in determining the bio-remediation capacities in polluted aquifers (DNA micro-arrays), 2) to monitor the microorganisms isolated for their degradative capacities during bio-remediation processes (fluorescent in situ hybridization or FISH) and 3) to create new tools for the detection and the quantification of ETBE or MTBE in contaminated aquifers (bio-sensor). The manuscript also describes the different ways for the adaptation of microorganisms to the presence of a xenobiotic compound. (author)

  14. Fabrication and properties of poly(polyethylene glycol n-alkyl ether vinyl ether)s as polymeric phase change materials

    International Nuclear Information System (INIS)

    Pei, Dong-fang; Chen, Sai; Li, Shu-qin; Shi, Hai-feng; Li, Wei; Li, Xuan; Zhang, Xing-xiang

    2016-01-01

    A series of poly(polyethylene glycol n-alkyl ether vinyl ether)s (PC m E n VEs) with various lengths of alkyl chains and polyethylene glycol spacers as side chain (m = 16,18; n = 1,2) were synthesized via two steps. First, monomers-ethylene glycol hexadecyl ether vinyl ether (C 16 E 1 VE), ethylene glycol octadecyl ether vinyl ether (C 18 E 1 VE), diethylene glycol hexadecyl ether vinyl ether (C 16 E 2 VE) and diethylene glycol octadecyl ether vinyl ether (C 18 E 2 VE) were synthesized by a modified Williamson etherification. Then, four new types of phase change materials were successfully fabricated by a living cationic polymerization. Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) were employed to characterize their composition, thermal properties and crystallization behavior. The results show that, the side chains of PC 16 E 1 VE, PC 18 E 1 VE, PC 16 E 2 VE and PC 18 E 2 VE are in a hexagonal lattice, and the onset temperatures for melting of PC 16 E 1 VE, PC 18 E 1 VE, PC 16 E 2 VE and PC 18 E 2 VE are 39.8 °C, 37.4 °C, 51.0 °C and 48.9 °C, the onset temperatures for crystallization are 36.7 °C, 35.2 °C, 47.4 °C and 46.3 °C, respectively. The enthalpy changes of PC 18 E 1 VE, PC 16 E 2 VE and PC 18 E 2 VE are higher than 100 J/g; on the contrary, it is 96 J/g for PC 16 E 1 VE. The enthalpy decrease is no more than 11% after 10 heating and cooling cycles. The 5 wt% mass loss temperatures of PC 18 E 1 VE, PC 16 E 2 VE and PC 18 E 2 VE are higher than 300 °C; on the contrary, it’s 283 °C for PC 16 E 1 VE. Using a weak polarity, flexible alkyl ether chain (-OCH 2 CH 2 O-) as a spacer to link the main chain and side chain is conducive to the crystallization of the alkyl side chain. These new phase change materials can be applied in heat storage, energy conservation, and environmental protection.

  15. Adsorción de resorcinol desde solución acuosa sobre carbón activado. relación isotermas de adsorción y entalpía de inmersión

    OpenAIRE

    Blanco, Diego; Moreno, Juan; Giraldo, Liliana

    2009-01-01

    Se estudia la adsorción de resorcinol, sobre carbones activados modificados, obtenidos a partir de un carbón activado comercial CarbochemTM –PS30, CAG, por medio de tratamiento químico con HNO3 7M, CAO y tratamiento térmico bajo flujo de H2, CAR; se analiza la influencia del pH de la solución, la reducción y oxidación de la superficie del carbón y se determina la entalpía de inmersión de los carbones activados en soluciones acuosas de resorcinol.La interacción sólido-solución se caracteriza...

  16. The Ether Wind and the Global Positioning System.

    Science.gov (United States)

    Muller, Rainer

    2000-01-01

    Explains how students can perform a refutation of the ether theory using information from the Global Positioning System (GPS). Discusses the functioning of the GPS, qualitatively describes how position determination would be affected by an ether wind, and illustrates the pertinent ideas with a simple quantitative model. (WRM)

  17. Dimethyl ether as a drift-chamber gas

    International Nuclear Information System (INIS)

    Bari, G.; Basile, M.; Bonvicini, G.; Cara Romeo, G.; Casaccia, R.; Cifarelli, L.; Cindolo, F.; Contin, A.; D'Ali, G.; Del Papa, C.; Focardi, S.; Iacobucci, G.; Maccarrone, G.; Massam, T.; Motta, F.; Nania, R.; Palmonari, F.; Prisco, G.; Sartorelli, G.; Susinno, G.; Votano, L.; Zichichi, A.; Istituto Nazionale di Fisica Nucleare, Bologna; European Organization for Nuclear Research, Geneva; Istituto Nazionale di Fisica Nucleare, Frascati; Michigan Univ., Ann Arbor; Palermo Univ.

    1986-01-01

    We have continued the testing of dimethyl ether as a drift-chamber gas in order to improve the understanding of its properties. In particular, we report on measurement accuracy, on systematic effects, and some preliminary data on the ageing of a detector filled with dimethyl ether. (orig.)

  18. Influence of structure of crown ethers on their radiation stability

    International Nuclear Information System (INIS)

    Grigor'ev, E.I.; Myasoedova, T.G.; Nesterov, S.V.; Trakhtenberg, L.I.

    1988-01-01

    Primary products of γ-radiolysis of crown ethers with the same size of the macrocyclic ring and different substituents were studied by EPR and mass spectrometry. It was shown that introduction of substituents into the polyether ring increases the radiation stability of crown ethers due to intramolecular transfer of energy from the polyether ring to a substituent

  19. Congenital malformations and maternal occupational exposure to glycol ethers

    NARCIS (Netherlands)

    Cordier, S; Bergeret, A; Goujard, J; Ha, MC; Ayme, S; Calzolari, E; DeWalle, HEK; KnillJones, R; Candela, S; Dale, [No Value; Dananche, B; deVigan, C; Fevotte, J; Kiel, G; Mandereau, L

    Glycol ethers are found in a wide range of domestic and industrial products, many of which are used in women's work environments. Motivated by concern about their potential reproductive toxicity, we have evaluated the risk of congenital malformations related to glycol ether exposure during preg

  20. Application of simplified PC-SAFT to glycol ethers

    DEFF Research Database (Denmark)

    Avlund, Ane Søgaard; Kontogeorgis, Georgios; Michelsen, Michael Locht

    2012-01-01

    The simplified PC-SAFT (sPC-SAFT) equation of state is applied for binary glycol ether-containing mixtures, and it is investigated how the results are influenced by inclusion of intramolecular association in the association theory. Three different glycol ethers are examined: 2-methoxyethanol, 2...

  1. Catalytic hydroprocessing of lignin β-O-4 ether bond model compound phenethyl phenyl ether over ruthenium catalysts

    NARCIS (Netherlands)

    Gomez-Monedero, B.; Faria, J.; Bimbela, F.; Ruiz, M.P.

    2017-01-01

    The catalytic hydroprocessing of phenethyl phenyl ether (PPE), a model compound of one of the most significant ether linkages within lignin structure, β-O-4, has been studied. Reactions were carried out using two ruthenium-based catalysts, supported on different materials: 3.8 wt.% Ru/C and 3.9 wt.%

  2. Structuring of poly ether ether ketone by ArF excimer laser radiation in different atmospheres

    International Nuclear Information System (INIS)

    Feng, Y.; Gottmann, J.; Kreutz, E.W.

    2003-01-01

    Structuring of poly ether ether ketone (PEEK) by 193 nm ArF excimer laser radiation has been investigated. Experiments were carried out in different atmospheres (air, vacuum, Ar, O 2 ) in order to study its influence on the quality of the structures and the formation of the debris. Repetition rate makes little effect on the ablation rate and roughness of the structure in presence of any kind of atmosphere, indicating for the structuring of PEEK by ArF laser radiation a large window of processing. The roughness at the bottom of the structures and the morphology of the side walls are strongly affected by the properties of the atmosphere. The smallest roughness is achieved at 0.6 J/cm 2 for all kinds of processing gases. Debris around the structures can be diminished by structuring in vacuum. Plasma expansion speed has been measured by using high speed photography

  3. Sulfonated poly(tetramethydiphenyl ether ether ketone) membranes for vanadium redox flow battery application

    Energy Technology Data Exchange (ETDEWEB)

    Mai, Zhensheng; Bi, Cheng; Dai, Hua [PEMFC Key Materials and Technology Laboratory, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian 116023 (China); Graduate University of the Chinese Academy of Sciences, Beijing 100039 (China); Zhang, Huamin; Li, Xianfeng [PEMFC Key Materials and Technology Laboratory, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian 116023 (China)

    2011-01-01

    Sulfonated poly(tetramethydiphenyl ether ether ketone) (SPEEK) with various degree of sulfonation is prepared and first used as ion exchange membrane for vanadium redox flow battery (VRB) application. The vanadium ion permeability of SPEEK40 membrane is one order of magnitude lower than that of Nafion 115 membrane. The low cost SPEEK membranes exhibit a better performance than Nafion at the same operating condition. VRB single cells with SPEEK membranes show very high energy efficiency (>84%), comparable to that of the Nafion, but at much higher columbic efficiency (>97%). In the self-discharge test, the duration of the cell with the SPEEK membrane is two times longer than that with Nafion 115. The membrane keeps a stable performance after 80-cycles charge-discharge test. (author)

  4. Origin of mechanical modifications in poly (ether ether ketone)/carbon nanotube composite

    International Nuclear Information System (INIS)

    Pavlenko, Ekaterina; Puech, Pascal; Bacsa, Wolfgang; Boyer, François; Olivier, Philippe; Sapelkin, Andrei; King, Stephen; Heenan, Richard; Pons, François; Gauthier, Bénédicte; Cadaux, Pierre-Henri

    2014-01-01

    Variations in the hardness of a poly (ether ether ketone) beam electrically modified with multi-walled carbon nanotubes (MWCNT, 0.5%-3%) are investigated. It is shown that both rupture and hardness variations correlate with the changes in carbon nanotube concentration when using micro indentation and extended Raman imaging. Statistical analysis of the relative spectral intensities in the Raman image is used to estimate local tube concentration and polymer crystallinity. We show that the histogram of the Raman D band across the image provides information about the amount of MWCNTs and the dispersion of MWCNTs in the composite. We speculate that we have observed a local modification of the ordering between pure and modified polymer. This is partially supported by small angle neutron scattering measurements, which indicate that the agglomeration state of the MWCNTs is the same at the concentrations studied.

  5. Origin of mechanical modifications in poly (ether ether ketone)/carbon nanotube composite

    Energy Technology Data Exchange (ETDEWEB)

    Pavlenko, Ekaterina; Puech, Pascal; Bacsa, Wolfgang, E-mail: wolfgang.bacsa@cemes.fr [CEMES-CNRS and University of Toulouse, 29 Jeanne Marvig, 31055 Toulouse (France); Boyer, François; Olivier, Philippe [Université de Toulouse, Institut Clément Ader, I.U.T. Université Paul Sabatier - 133C Avenue de Rangueil - B.P. 67701, 31077 Toulouse CEDEX 4 (France); Sapelkin, Andrei [School of Physics and Astronomy, Queen Mary, University of London, Mile End Road, E1 4NS London (United Kingdom); King, Stephen; Heenan, Richard [ISIS Facility, Rutherford Appleton Laboratory, Chilton, OX11 0QX Didcot (United Kingdom); Pons, François; Gauthier, Bénédicte; Cadaux, Pierre-Henri [AIRBUS FRANCE (B.E. M and P Toulouse), 316 Route de Bayonne, 31060 Toulouse (France)

    2014-06-21

    Variations in the hardness of a poly (ether ether ketone) beam electrically modified with multi-walled carbon nanotubes (MWCNT, 0.5%-3%) are investigated. It is shown that both rupture and hardness variations correlate with the changes in carbon nanotube concentration when using micro indentation and extended Raman imaging. Statistical analysis of the relative spectral intensities in the Raman image is used to estimate local tube concentration and polymer crystallinity. We show that the histogram of the Raman D band across the image provides information about the amount of MWCNTs and the dispersion of MWCNTs in the composite. We speculate that we have observed a local modification of the ordering between pure and modified polymer. This is partially supported by small angle neutron scattering measurements, which indicate that the agglomeration state of the MWCNTs is the same at the concentrations studied.

  6. Sulfonated poly(ether ether ketone) membranes for electric double layer capacitors

    International Nuclear Information System (INIS)

    Kim, Wan Ju; Kim, Dong-Won

    2008-01-01

    Sulfonated poly(ether ether ketone) (S-PEEK) with different degree of sulfonation (DS) has been prepared and evaluated as a proton conducting membrane for electric double layer capacitor (EDLC). The polymer electrolytes prepared with S-PEEK membrane exhibited ionic conductivities about 1.2 x 10 -3 -4.5 x 10 -3 S cm -1 at room temperature, which depended on both soaking solvent and degree of sulfonation. The quasi-solid-state EDLCs consisted of activated carbon electrodes and S-PEEK membrane were assembled, and their electrochemical characteristics were studied by cyclic voltammetry and charge-discharge cycle tests. The effect of DS on the electrochemical performances of EDLCs has been investigated

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

    International Nuclear Information System (INIS)

    Conceicao, T.F.; Bertolino, J.R.; Barra, G.M.O.; Pires, A.T.N.

    2009-01-01

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

  8. Characterization of melt-blended graphene – poly(ether ether ketone) nanocomposite

    International Nuclear Information System (INIS)

    Tewatia, Arya; Hendrix, Justin; Dong, Zhizhong; Taghon, Meredith; Tse, Stephen; Chiu, Gordon; Mayo, William E.; Kear, Bernard; Nosker, Thomas; Lynch, Jennifer

    2017-01-01

    Using a high shear melt-processing method, graphene-reinforced polymer matrix composites (G-PMCs) were produced with good distribution and particle–matrix interaction of bi/trilayer graphene at 2 wt. % and 5 wt. % in poly ether ether ketone (2Gn-PEEK and 5Gn-PEEK). The morphology, structure, thermal properties, and mechanical properties of PEEK, 2Gn-PEEK and 5 Gn-PEEK were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), flexural mechanical testing, and dynamic mechanical analysis (DMA). Addition of graphene to PEEK induces surface crystallization, increased percent crystallinity, offers a composite that is thermally stable until 550 °C and enhances thermomechanical properties. Results show that graphene was successfully melt-blended within PEEK using this method.

  9. Analysis of electron-irradiated poly-ether ether ketone by X-ray photoelectron spectroscopy

    International Nuclear Information System (INIS)

    Oyabu, Matashige; Kobayashi, Yoshinori; Seguchi, Tadao; Sasuga, Tsuneo; Kudoh, Hisaaki.

    1995-01-01

    Organic polymers used in atomic power plants or space are damaged by ionizing irradiation. Radicals produced by irradiation cause oxidation, chain scission and crosslinking, all of which lead to degradation of the material. In this paper, the surface of electron-irradiated poly-ether ether ketone (PEEK) was studied by X-ray photoelectron spectroscopy (XPS). The irradiation in air was found to oxidize the PEEK surface producing carboxyl groups, the content of which dependant on the dose. Carboxyl groups were not produced in helium gas. Quantitative spectral analysis indicated that the aromatic structure might be decomposed. Some comparison was made between the semicrystalline and amorphous samples. The oxygen content resulting from irradiation, of semicrystalline PEEK increased more than that of amorphous PEEK. (author)

  10. Enhanced osteogenic activity of poly ether ether ketone using calcium plasma immersion ion implantation.

    Science.gov (United States)

    Lu, Tao; Qian, Shi; Meng, Fanhao; Ning, Congqin; Liu, Xuanyong

    2016-06-01

    As a promising implantable material, poly ether ether ketone (PEEK) possesses similar elastic modulus to that of cortical bones yet suffers from bio-inertness and poor osteogenic properties, which limits its application as orthopedic implants. In this work, calcium is introduced onto PEEK surface using calcium plasma immersion ion implantation (Ca-PIII). The results obtained from scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) confirm the modified layer with varying contents of calcium are formed on PEEK surfaces. Water contact angle measurements reveal the increasing hydrophobicity of both Ca-PIII treated surfaces. In vitro cell adhesion, viability assay, alkaline phosphatase activity and collagen secretion analyses disclose improved the adhesion, proliferation, and osteo-differentiation of rat bone mesenchymal stem cells (bMSCs) on Ca-PIII treated surfaces. The obtained results indicate that PEEK surface with enhanced osteogenic activity can be produced by calcium incorporation. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Characterization of melt-blended graphene – poly(ether ether ketone) nanocomposite

    Energy Technology Data Exchange (ETDEWEB)

    Tewatia, Arya; Hendrix, Justin [Department of Materials Science and Engineering, Rutgers University, 607 Taylor Road, Piscataway, NJ, 08854 (United States); Dong, Zhizhong [Department of Mechanical Engineering, Rutgers University, 98 Brett Road, Piscataway, NJ 08854 (United States); Taghon, Meredith [Department of Materials Science and Engineering, Rutgers University, 607 Taylor Road, Piscataway, NJ, 08854 (United States); Tse, Stephen [Department of Mechanical Engineering, Rutgers University, 98 Brett Road, Piscataway, NJ 08854 (United States); Chiu, Gordon; Mayo, William E.; Kear, Bernard; Nosker, Thomas [Department of Materials Science and Engineering, Rutgers University, 607 Taylor Road, Piscataway, NJ, 08854 (United States); Lynch, Jennifer, E-mail: jklynch@rci.rutgers.edu [Department of Materials Science and Engineering, Rutgers University, 607 Taylor Road, Piscataway, NJ, 08854 (United States)

    2017-02-15

    Using a high shear melt-processing method, graphene-reinforced polymer matrix composites (G-PMCs) were produced with good distribution and particle–matrix interaction of bi/trilayer graphene at 2 wt. % and 5 wt. % in poly ether ether ketone (2Gn-PEEK and 5Gn-PEEK). The morphology, structure, thermal properties, and mechanical properties of PEEK, 2Gn-PEEK and 5 Gn-PEEK were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), flexural mechanical testing, and dynamic mechanical analysis (DMA). Addition of graphene to PEEK induces surface crystallization, increased percent crystallinity, offers a composite that is thermally stable until 550 °C and enhances thermomechanical properties. Results show that graphene was successfully melt-blended within PEEK using this method.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-03-01

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

  13. 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)

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

    International Nuclear Information System (INIS)

    Silva, V.S.; Ruffmann, B.; Vetter, S.; Boaventura, M.; Mendes, A.M.; Madeira, L.M.; Nunes, S.P.

    2006-01-01

    Homogeneous membranes based on sulfonated poly(ether ether ketone) (sPEEK) with different sulfonation degrees (SD) were prepared and characterized. In order to perform a critical analysis of the SD effect on the polymer barrier and mass transport properties towards direct methanol fuel cell species, proton conductivity, water/methanol pervaporation and nitrogen/oxygen/carbon dioxide pressure rise method experiments are proposed. This procedure allows the evaluation of the individual permeability coefficients in hydrated sPEEK membranes with different sulfonation degrees. Nafion[reg] 112 was used as reference material. DMFC tests were also performed at 50 deg. C. It was observed that the proton conductivity and the permeability towards water, methanol, oxygen and carbon dioxide increase with the sPEEK sulfonation degree. In contrast, the SD seems to not affect the nitrogen permeability coefficient. In terms of selectivity, it was observed that the carbon dioxide/oxygen selectivity increases with the sPEEK SD. In contrast, the nitrogen/oxygen selectivity decreases. In terms of barrier properties for preventing the DMFC reactants loss, the polymer electrolyte membrane based on the sulfonated poly(ether ether ketone) with SD lower or equal to 71%, although having slightly lower proton conductivity, presented much better characteristics for fuel cell applications compared with the well known Nafion[reg] 112. In terms of the DMFC tests of the studied membranes at low temperature, the sPEEK membrane with SD = 71% showed to have similar performance, or even better, as that of Nafion[reg] 112. However, the highest DMFC overall efficiency was achieved using sPEEK membrane with SD = 52%

  15. Crown ether derivatives of EDTA: Pt. 6

    International Nuclear Information System (INIS)

    Liu Zhongqun; Qin Shengying; Chen Shaojin; Tan Lin

    1988-01-01

    EDTA-diaminodibenzo-18-crown-6 (cis- and trans-) condensation polymer is a new compound of crown ether derivatives of EDTA. In this paper the adsorption behaviors of U(IV) and U(VI) on this polymer from chloride solutions and effects of hydrochloric acid concentrations, salting-out agents and organic solvents on distribution coefficient (K d ) of uranium are investigated. Adsorption mechanism of uranyl ion (UO 2 2+ ) on this polymer was studied with IR spectra and by means of the adsorption behaviors of compounds of similar structure. Experimental results show that both polyether section and carboxyl groups in EDTA-diaminodibenzo-18-crown-6 take part in complexation with uranyl ion and synergistic effect appeared

  16. Effect of ethylene glycol monomethyl ether and diethylene glycol monomethyl ether on hepatic metabolizing enzymes.

    Science.gov (United States)

    Kawamoto, T; Matsuno, K; Kayama, F; Hirai, M; Arashidani, K; Yoshikawa, M; Kodama, Y

    1990-06-01

    Glycol ethers have been extensively used in industry over the past 40-50 years. Numerous studies on the toxicity of glycol ethers have been performed, however, the effects of glycol ethers on the hepatic drug metabolizing enzymes are still unknown. We studied the changes of the putative metabolic enzymes, that is, the hepatic microsomal mixed function oxidase system and cytosolic alcohol dehydrogenase, by the oral administration of diEGME and EGME. Adult male Wistar rats were used. DiEGME was administered orally; 500, 1000, 2000 mg/kg for 1, 2, 5 or 20 days and EGME was 100, 300 mg/kg for 1, 2, 5 or 20 days. Decreases in liver weights were produced by highest doses of diEGME (2000 mg/kg body wt/day for 20 days) and EGME (300 mg/kg body wt/day for 20 days). DiEGME increased hepatic microsomal protein contents and induced cytochrome P-450, but not cytochrome b5 or NADPH-cytochrome c reductase. The activity of cytosolic ADH was not affected by diEGME administration. On the other hand, EGME did not change cytochrome P-450, cytochrome b5 or NADPH-cytochrome c reductase. The activity of cytosolic ADH was increased by repeated EGME treatment. Therefore it is suspected that the enzyme which takes part in the metabolism of diEGME is different from that of EGME, although diEGME is a structural homologue of EGME.

  17. Biosynthesis of archaeal membrane ether lipids

    Directory of Open Access Journals (Sweden)

    Samta eJain

    2014-11-01

    Full Text Available A vital function of the cell membrane in all living organism is to maintain the membrane permeability barrier and fluidity. The composition of the phospholipid bilayer is distinct in archaea when compared to bacteria and eukarya. In archaea, isoprenoid hydrocarbon side chains are linked via an ether bond to the sn-glycerol-1-phosphate backbone. In bacteria and eukarya on the other hand, fatty acid side chains are linked via an ester bond to the sn-glycerol-3-phosphate backbone. The polar head groups are globally shared in the three domains of life. The unique membrane lipids of archaea have been implicated not only in the survival and adaptation of the organisms to extreme environments but also to form the basis of the membrane composition of the last universal common ancestor (LUCA. In nature, a diverse range of archaeal lipids is found, the most common are the diether (or archaeol and the tetraether (or caldarchaeol lipids that form a monolayer. Variations in chain length, cyclization and other modifications lead to diversification of these lipids. The biosynthesis of these lipids is not yet well understood however progress in the last decade has led to a comprehensive understanding of the biosynthesis of archaeol. This review describes the current knowledge of the biosynthetic pathway of archaeal ether lipids; insights on the stability and robustness of archaeal lipid membranes; and evolutionary aspects of the lipid divide and the last universal common ancestor LUCA. It examines recent advances made in the field of pathway reconstruction in bacteria.

  18. ADSORCIÓN DE RESORCINOL DESDE SOLUCIÓN ACUOSA SOBRE CARBÓN ACTIVADO. RELACIÓN ISOTERMAS DE ADSORCIÓN Y ENTALPÍA DE INMERSIÓN

    Directory of Open Access Journals (Sweden)

    Diego Blanco

    2009-04-01

    Full Text Available Se estudia la adsorción de resorcinol, sobre carbones activados modificados, obtenidos a partir de un carbón activado comercial CarbochemTM –PS30, CAG, por medio de tratamiento químico con HNO3 7M, CAO y tratamiento térmico bajo flujo de H2, CAR; se analiza la influencia del pH de la solución, la reducción y oxidación de la superficie del carbón y se determina la entalpía de inmersión de los carbones activados en soluciones acuosas de resorcinol.La interacción sólido-solución se caracteriza por el análisis de las isotermas de adsorción a 298 K a los pHs de 7, 9 y 11 con el propósito de evaluar el sistema sobre y por debajo del valor de las pKa del resorcinol. La capacidad de adsorción de los carbones aumenta al disminuir el pH de la solución. La cantidad retenida aumenta en el carbón reducido al pH de máxima adsorción y disminuye en el carbón oxidado. Los resultados experimentales de las isotermas de adsorción se ajustaron a los modelos de Freundlich y Langmuir, obteniendo valores para el parámetro Qmáx del modelo de Langmuir en el CAG de 179, 156 y 44 mgg-1, para valores de pH de 7, 9 y 11 respectivamente. En el caso de los carbones modificados se obtienen valores de 233, 179 y 164 mgg-1, para el CAR, CAG y CAO a pH 7 respectivamente. Como tendencia general la adsorción de resorcinol aumenta en el siguiente orden CAR > CAG > CAO Similares conclusiones se obtienen de las entalpías de inmersión, cuyos valores se incrementan con la cantidad de soluto retenido. En el caso del CAG se obtienen entalpías de inmersión entre 25,8 a 40,9 Jg-1 para soluciones acuosas de resorcinol en un rango de 20 a 1500 mgL-1.

  19. Chemical and radiation stability of SuperLig reg-sign 644, resorcinol-formaldehyde, and CS-100 cesium ion exchange materials

    International Nuclear Information System (INIS)

    Brown, G.N.; Adami, S.R.; Bray, L.A.

    1995-09-01

    At the request of the Initial Pretreatment Module Project within Westinghouse Hanford Company, Pacific Northwest Laboratory (PNL) conducted this study for the Efficient Separations and Processing Crosscutting Program (ESP) under the task ''Develop and Test Sorbents.'' The purpose of the study was to assess and compare the chemical and radiolytic stability of several cesium-selective ion exchange materials in simulated alkaline Hanford tank waste matrices. Pretreatment of nuclear process wastes to remove of cesium and other radionuclides by ion exchange was proposed previously as one method of minimizing the amount of high-level radioactive waste at Hanford. In this study, PNL evaluated three cesium-selective materials SuperLig reg-sign 644, resorcinol-formaldehyde (R-F), and CS-100 for chemical and radiation stability in 1 M NaOH and a simulated neutralized current acid waste (NCAW). The objective of the study is to investigate the stability of the newly produced SuperLig reg-sign 644 under a variety of conditions in an attempt to simulate and predict the degradation process. The following specific conclusions and recommendations resulted from the study

  20. Extractive spectrophotometric determination of molybdenum in steels and nickel base high-temperature alloys as a ternary complex with hydroxylamine hydrochloride and 4-(2-pyridylazo) resorcinol

    International Nuclear Information System (INIS)

    Reddy, M.R.P.; Kumar, P.V.S.; Shyamsundar, J.P.; Anjaneyulu, Y.

    1990-01-01

    The red coloured, ternary complex formed by molybdenum(VI) with hydroxylamine hydrchloride and 4-(2-pyridylazo) resorcinol (PAR), on heating for 20 minutes in a hot water bath at pH 6-8, can be extracted with a mixture of n-butanol and benzene (4:1). This complex exhibits absorption maximum at 530nm with a molar absorptivity of 2.8x10 4 lit. mol -1 cm -1 and obeys Beer's law upto 4.5μg/ml of Mo(VI). The composition of the complex is found to be 1:1:1, for Mo(VI): hydroxylamine hydrochloride: PAR. Large amounts of tartaric acid and 2, 2-diamino-cyclohexane tetra acetic acid (CyDTA) can be tolerated in this method. The extraction becomes highly selective in presence of CyDTA (3ml of 5x10 -2 M) and interference of ions like Fe(III)(5mg), Pb(II)(4mg), Zn(II)(2mg), Cu(II)(4mg), Mn(II)(3mg), Ni(II)(4mg), Sn(II)(3mg), Cr(VI)(2mg) and Bi(III)(0.5mg) can be effectively supressed in the determination of 10-45μg of molybdenum. The method can be successfully applied for the determination of molybdenum in steels and nickel base high temperature alloys. (author). 2 tabs., 8 refs

  1. Chemical and radiation stability of SuperLig{reg_sign}644, resorcinol-formaldehyde, and CS-100 cesium ion exchange materials

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G.N.; Adami, S.R.; Bray, L.A. [and others

    1995-09-01

    At the request of the Initial Pretreatment Module Project within Westinghouse Hanford Company, Pacific Northwest Laboratory (PNL) conducted this study for the Efficient Separations and Processing Crosscutting Program (ESP) under the task ``Develop and Test Sorbents.`` The purpose of the study was to assess and compare the chemical and radiolytic stability of several cesium-selective ion exchange materials in simulated alkaline Hanford tank waste matrices. Pretreatment of nuclear process wastes to remove of cesium and other radionuclides by ion exchange was proposed previously as one method of minimizing the amount of high-level radioactive waste at Hanford. In this study, PNL evaluated three cesium-selective materials SuperLig{reg_sign}644, resorcinol-formaldehyde (R-F), and CS-100 for chemical and radiation stability in 1 M NaOH and a simulated neutralized current acid waste (NCAW). The objective of the study is to investigate the stability of the newly produced SuperLig{reg_sign}644 under a variety of conditions in an attempt to simulate and predict the degradation process. The following specific conclusions and recommendations resulted from the study.

  2. Ultrasensitive and simultaneous detection of hydroquinone, catechol and resorcinol based on the electrochemical co-reduction prepared Au-Pd nanoflower/reduced graphene oxide nanocomposite

    International Nuclear Information System (INIS)

    Chen, Yuan; Liu, Xiaoying; Zhang, Si; Yang, Liuqing; Liu, Meiling; Zhang, Youyu; Yao, Shouzhuo

    2017-01-01

    A simple and efficient eletrochemical sensing platform for simultaneous detection of hydroquinone (HQ), catechol (CC) and resorcinol (RC) based on the Au-Pd bimetallic and graphene is described in this paper. The Au-Pd reduced graphene oxide (Au-Pd NF/rGO) was prepared by the electrochemical co-reduction deposition via cyclic voltammetry method (CV). The Au-Pd NF/rGO nanocomposite was examined by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and electrochemical methods CV and differential pulse voltammety (DPV) study showed that the three dihydroxybenzene isomers can be catalytically oxidized and discriminated simultaneously on the Au-Pd NF/rGO/GCE. The presence of Pd makes the performance of the sensor superior to that of in the absence of it. Owing to the integrated superior conductivity and excellent catalytic property of Au-Pd NF/rGO, the sensitive and simultaneous detection of HQ, CC and RC was realized in the individual or triple-components solution based on the as proposed Au-Pd NF/rGO/GCE, which shows wide linear range and low detection limit. The detection of them in tap water, river water and lake water were also successfully performed and good recovery was obtained.

  3. Discovery of 2,4-diarylaminopyrimidines bearing a resorcinol motif as novel ALK inhibitors to overcome the G1202R resistant mutation.

    Science.gov (United States)

    Geng, Kaijun; Xia, Zongjun; Ji, Yinchun; Zhang, Ruisi Ruthy; Sun, Deqiao; Ai, Jing; Song, Zilan; Geng, Meiyu; Zhang, Ao

    2018-01-20

    To address drug resistance caused by ALK kinase mutations, especially the most refractory and predominant mutation G1202R for the second-generation ALK inhibitor, a series of new diarylaminopyrimidine analogues were designed by incorporating a resorcinol moiety (A-ring) to interact the ALK kinase domain where the G1202R is located. Compound 12d turns out as the most potent with IC 50 values of 1.7, 3.5, and 1.8 nM against ALK wild type, gatekeeper mutant L1196M, and the G1202R mutant, respectively. More importantly, compound 12d has excellent inhibitory effects against the proliferation of BaF3 cells specifically expressing ALK wild type, gatekeeper L1196M, and the most challenging mutant G1202R, with IC 50 values all less than 1.5 nM. Collectively, compound 12d is worthy of further investigation as a new more potent third-generation ALK inhibitor to circumvent drug resistance of both the first-generation and the second-generation inhibitors. Copyright © 2017. Published by Elsevier Masson SAS.

  4. Characterization of Microsolvated Crown Ethers from Broadband Rotational Spectroscopy

    Science.gov (United States)

    Perez, Cristobal; Schnell, Melanie; Blanco, Susana; Lopez, Juan Carlos

    2016-06-01

    Since they were first synthetized, crown ethers have been extensively used in organometallic chemistry due to their unparalleled binding selectivity with alkali metal cations. From a structural point of view, crown ethers are heterocycles containing oxygen and/or other heteroatoms, although the most common ones are formed from ethylene oxide unit. Crown ethers are conventionally seen as being hydrophilic inside and hydrophobic outside when the structures found for the metal cation complexes are considered. However, crown ethers are extremely flexible and in isolation may present a variety of stable conformations so that their structure may be easily adapted in presence of a strong ligand as an alkali metal cation minimize the energy of the resulting complex. Water can be considered a soft ligand which interacts with crown ethers through moderate hydrogen bonds. It is thus interesting to investigate which conformers are selected by water to form complexes, the preferred interaction sites and the possible conformational changes due to the presence of one or more water molecules. Previous studies identified microsolvated crown ethers but in all cases with a chromophore group attached to the structure. Here we present a broadband rotational spectroscopy study of microsolvated crown ethers produced in a pulsed molecular jet expansion. Several 1:1 and 1:2 crown ether:water aggregates are presented for 12-crown-4, 15-crown-5 and 18-crown-6. Unambiguous identification of the structures has been achieved using isotopic substitution within the water unit. The subtle changes induced in the structures of the crown ether monomer upon complexation and the hydrogen-bonding network that hold them together will be also discussed. F. Gámez, B. Martínez-Haya, S. Blanco,J. C. López and J. L. Alonso, Phys. Chem. Chem. Phys. 2014, 14 12912-12918 V. A. Shubert, C.W. Müller and T. Zwier, J. Phys. Chem. A 2009, 113 8067-8079

  5. Encapsulation/Fixation (E/F) Mechanisms.

    Science.gov (United States)

    1984-06-18

    substituting the lower molecular weight, RF-475, neopentyl glycol diglycidyl ether, for a portion of the EPON 828. An effective working ratio for our studies...temperature cure ** Neopentyl Glycol Diglycidyl Ether Ingredients Weight Sulfurous Binder* Percent Sulfur 55 - 100 Unsaturated monomers** 45 - 0 *Themofomed at...enetri ni tramine RF-475 Neopentyl Glycol Diglycidyl Ether SEM Scanning Electron Microscope TEM Transmission Electron Microscope TNT Trinitrotoluene

  6. Evaluation of crystallization kinetics of poly (ether-ketone-ketone and poly (ether-ether-ketone by DSC

    Directory of Open Access Journals (Sweden)

    Gibran da Cunha Vasconcelos

    2010-08-01

    Full Text Available The poly (aryl ether ketones are used as matrices in advanced composites with high performance due to its high thermal stability, excellent environmental performance and superior mechanical properties. Most of the physical, mechanical and thermodynamic properties of semi-crystalline polymers depend on the degree of crystallinity and morphology of the crystalline regions. Thus, a study on the crystallization process promotes a good prediction of how the manufacturing parameters affect the developed structure, and the properties of the final product. The objective of this work was to evaluate the thermoplastics polymers PEKK e PEEK by DSC, aiming to obtain the relationship between kinetics, content, nucleation and geometry of the crystalline phases, according to the parameters of the Avrami and Kissinger models. The analysis of the Avrami exponents obtained for the studied polymers indicates that both showed the formation of crystalline phases with heterogeneous nucleation and growth geometry of the type sticks or discs, depending on the cooling conditions. It was also found that the PEEK has a higher crystallinity than PEKK.

  7. Nickel-catalyzed direct synthesis of dialkoxymethane ethers

    Indian Academy of Sciences (India)

    MURUGAN SUBARAMANIAN

    Nickel catalysis; alcohol; paraformaldehyde; ether; solvent-free condition. 1. Introduction ..... oxidation and Dopamine Release with Protective Effects. Against Central ... P, Ghosh A, Saha R and Saha B 2016 A Review on the. Advancement of ...

  8. Thermally reversible cross-linked poly(ether-urethanes

    Directory of Open Access Journals (Sweden)

    V. Gaina

    2013-07-01

    Full Text Available Cross-linked poly(ether-urethanes were prepared by Diels-Alder (DA reaction of the furan-containing poly(ether-urethane to bismaleimides and showed thermal reversibility evidenced by differential scanning calorimetry and attenuated total reflectance in conjunction with Fourier transform infrared spectroscopy (ATR-FTIR. The furan-containing poly(ether-urethanes were synthesized by the polyaddition reaction of 1,6-hexamethylene diisocyanate (HMDI or 4,4'- dibenzyl diisocyanate (DBDI to poly(tetramethylene ether glycol (PTMEG having Mn = 250, 650, 1000, 1500 and 2000 and 2-[N,N-bis(2-methyl-2-hydroxyethylamino]furfuryl as chain extender by the solution prepolymer method. The molar ratio of isocyanate: PTMEG:chain extender varied from 2:1:1 to 4:1:3, which produces a molar concentration of furyl group ranging between 3.65•10–4 and 1.25•10–3 mol/g.

  9. Chemical Composition and Cytotoxic Activities of Petroleum Ether ...

    African Journals Online (AJOL)

    Methods: The composition of petroleum ether extract was analyzed by gas ... acids, sterides, pregnanones, terpenes, alkaloids, alkenes, alcohols, ketones, aldehydes and other compounds. .... and mass spectra with those obtained from the.

  10. Poly (ether imide sulfone) membranes from solutions in ionic liquids

    KAUST Repository

    Kim, Dooli; Nunes, Suzana Pereira

    2017-01-01

    A membrane manufacture method based on non-volatile solvents and a high performance polymer, poly (ether imide sulfone) (EXTEM™), is proposed, as greener alternative to currently industrial process. We dissolved EXTEM™ in pure ionic liquids: 1-ethyl

  11. Spatial trends of polybrominated diphenyl ether (PBDE) congeners

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spatial trends of polybrominated diphenyl ether (PBDE) congeners were analyzed in young of the year bluefish collected along the U.S. Atlantic coastline from...

  12. Palladium-Catalyzed Reductive Insertion of Alcohols into Aryl Ether Bonds

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Meng [Institute for Integrated Catalysis, Pacific Northwest National Laboratory, P.O. Box 999 Richland WA 99352 USA; Gutiérrez, Oliver Y. [Institute for Integrated Catalysis, Pacific Northwest National Laboratory, P.O. Box 999 Richland WA 99352 USA; Camaioni, Donald M. [Institute for Integrated Catalysis, Pacific Northwest National Laboratory, P.O. Box 999 Richland WA 99352 USA; Lercher, Johannes A. [Institute for Integrated Catalysis, Pacific Northwest National Laboratory, P.O. Box 999 Richland WA 99352 USA; Department of Chemistry and Catalysis Research Institute, TU München, Lichtenbergstrasse 4 85748 Garching Germany

    2018-03-06

    Pd/C catalyzes C-O bond cleavage of aryl ethers (diphenyl ether and cyclohexyl phenyl ether) by methanol in H2. The aromatic C-O bond is cleaved by reductive methanolysis, which is initiated by Pd-catalyzed partial hydrogenation of one phenyl ring to form an enol ether. The enol ether reacts rapidly with methanol to form a ketal, which generates methoxycyclohexene by eliminating phenol or an alkanol. Subsequent hydrogenation leads to methoxycyclohexane.

  13. Investigation of ammonium trinitratouranylate complexing with diethyl ether

    International Nuclear Information System (INIS)

    Khod'ko, N.N.; Kolevich, T.A.; Umrejko, D.S.

    1989-01-01

    Interaction of ammonium trinitratouranylate (ATNU) with diethyl ether is investigated. It is shown, that adduct of UO 2 (NO 3 ) 2 · 2(C 2 H 5 ) 2 O coposition is formed in the indicated solvent due to incongruent solubility of ANTU. Analogous compound is obtained at ether effect on uranyl anhydrous nitrate. The matter is determined and investigated by means of chemical, thermal analyses and oscillating spectroscopy

  14. Glycerol tertiary butyl ethers via etherification of glycerol with isobutene

    Energy Technology Data Exchange (ETDEWEB)

    Behr, A. [Dortmund Univ. (Germany). Chair of Chemical Process Development/Technical Chemistry A

    2007-07-01

    Glycerol and isobutene can react to a mixture of glycerol tertiary butyl ethers (GTBE) which can be used as additives for gasoline, diesel or biodiesel. This reaction was investigated in lab scale yielding a proposal for a process flow diagram containing reaction, extraction, flash and rectification units. This process has the advantages that only the suitable higher ethers are formed and that both glycerol and isobutene are fully converted. The homogeneous acid catalyst is low-priced and can be completely recycled. (orig.)

  15. Children's exposure to polybrominated diphenyl ethers.

    Science.gov (United States)

    Zuurbier, Moniek; Leijs, Marike; Schoeters, Greet; ten Tusscher, Gavin; Koppe, Janna G

    2006-10-01

    Polybrominated biphenyl ethers (PBDEs), a class of brominated flame retardants, are frequently used in consumer products. PBDEs levels in environmental and human samples have increased in recent decades. Children are exposed to PBDEs through diet, mainly through fish, meat and milk. Total dietary exposure of children in Europe was calculated to be 2-3 ng/kg b.w./day. For nursing infants the main source of PBDE exposure is breast milk; exposure levels are around 15 ng/kg b.w./day. PBDE exposure levels in North America are 10 to a 100 times higher. Because of their persistence and their similarity to polychlorinated biphenyls (PCBs), concern has been raised about the effects of PBDEs on human health. Exposure to penta- and octa-BDE led to learning impairment and impaired motor behaviour in rodents. Exposure to penta-, octa- and also deca-BDE caused effects on thyroid homeostasis in animals. The EU has banned the production and use of penta- and octa-BDE since 2004; however, exposure will continue during the coming decades. Based upon current toxicological evidence, human exposure to deca-BDEs is not expected to lead to health effects, but data on exposure to deca-BDE and data on toxicity of deca-BDE are scarce. Therefore, monitoring studies and toxicity studies on deca-BDEs and other BDEs should continue.

  16. Radiation induced crosslinking of cellulose ethers

    International Nuclear Information System (INIS)

    Wach, A.R.; Mitomo, H.; Yoshii, F.; Kume, T.

    2002-01-01

    The effects of high-energy radiation on four ethers of cellulose: carboxymethyl (CMC); hydroxypropyl (HPC), hydroxyethyl (HEC) and methylcellulose (MC) were investigated. Polymers are irradiated in solid state and in aqueous solutions at various concentrations. Degree of substitution (DS) of the derivatives, the concentration of their aqueous solutions and irradiation conditions had a significant impact on the obtained products. Irradiation of polymers in solid state and in diluted aqueous solutions resulted in their degradation. However, it was found that for concentrated solutions gel formation occurred. Paste-like form of the initial material, when water plasticizes the bulk of polymer as well as the high dose rate, what prevents oxygen penetration of the polymer during irradiation, have been found favourable for hydrogel formation. Up to 95% of gel fraction was obtained from solutions of CMC with concentration over 50% irradiated by γ-rays or electron beam. It was pointed out that the ability to the formation of the three-dimensional network is related to the DS of anhydroglucose units and a type of chemical group introduced to main chain of cellulose. Produced hydrogels swelled markedly in water. Despite of the crosslinked structure they underwent degradation by the action of cellulase enzyme or microorganisms from compost, and can be included into the group of biodegradable materials. (author)

  17. Removal of reactive red-120 and 4-(2-pyridylazo) resorcinol from aqueous samples by Fe3O4 magnetic nanoparticles using ionic liquid as modifier.

    Science.gov (United States)

    Absalan, Ghodratollah; Asadi, Mozaffar; Kamran, Sedigheh; Sheikhian, Leila; Goltz, Douglas M

    2011-08-30

    The nanoparticles of Fe(3)O(4) as well as the binary nanoparticles of ionic liquid and Fe(3)O(4) (IL-Fe(3)O(4)) were synthesized for removal of reactive red 120 (RR-120) and 4-(2-pyridylazo) resorcinol (PAR) as model azo dyes from aqueous solutions. The mean size and the surface morphology of the nanoparticles were characterized by TEM, DLS, XRD, FTIR and TGA techniques. Adsorption of RR-120 and PAR was studied in a batch reactor at different experimental conditions such as nanoparticle dosage, dye concentration, pH of the solution, ionic strength, and contact time. Experimental results indicated that the IL-Fe(3)O(4) nanoparticles had removed more than 98% of both dyes under the optimum operational conditions of a dosage of 60mg, a pH of 2.5, and a contact time of 2min when initial dyes concentrations of 10-200mg L(-1) were used. The maximum adsorption capacity of IL-Fe(3)O(4) was 166.67 and 49.26mg g(-1) for RR-120 and PAR, respectively. The isotherm experiments revealed that the Langmuir model attained better fits to the equilibrium data than the Freundlich model. The Langmuir adsorption constants were 5.99 and 3.62L mg(-1) for adsorptions of RR-120 and PAR, respectively. Both adsorption processes were endothermic and dyes could be desorbed from IL-Fe(3)O(4) by using a mixed NaCl-acetone solution and adsorbent was reusable. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Removal of reactive red-120 and 4-(2-pyridylazo) resorcinol from aqueous samples by Fe3O4 magnetic nanoparticles using ionic liquid as modifier

    International Nuclear Information System (INIS)

    Absalan, Ghodratollah; Asadi, Mozaffar; Kamran, Sedigheh; Sheikhian, Leila; Goltz, Douglas M.

    2011-01-01

    Highlights: → Ionic liquids modify the dye-adsorption characteristics of magnetic nanoparticles. → Modified nanoparticles improved the sensitivity of dye measurements. → Water-solubility is an important factor for choosing an ionic liquid as a modifier for nanoparticles. - Abstract: The nanoparticles of Fe 3 O 4 as well as the binary nanoparticles of ionic liquid and Fe 3 O 4 (IL-Fe 3 O 4 ) were synthesized for removal of reactive red 120 (RR-120) and 4-(2-pyridylazo) resorcinol (PAR) as model azo dyes from aqueous solutions. The mean size and the surface morphology of the nanoparticles were characterized by TEM, DLS, XRD, FTIR and TGA techniques. Adsorption of RR-120 and PAR was studied in a batch reactor at different experimental conditions such as nanoparticle dosage, dye concentration, pH of the solution, ionic strength, and contact time. Experimental results indicated that the IL-Fe 3 O 4 nanoparticles had removed more than 98% of both dyes under the optimum operational conditions of a dosage of 60 mg, a pH of 2.5, and a contact time of 2 min when initial dyes concentrations of 10-200 mg L -1 were used. The maximum adsorption capacity of IL-Fe 3 O 4 was 166.67 and 49.26 mg g -1 for RR-120 and PAR, respectively. The isotherm experiments revealed that the Langmuir model attained better fits to the equilibrium data than the Freundlich model. The Langmuir adsorption constants were 5.99 and 3.62 L mg -1 for adsorptions of RR-120 and PAR, respectively. Both adsorption processes were endothermic and dyes could be desorbed from IL-Fe 3 O 4 by using a mixed NaCl-acetone solution and adsorbent was reusable.

  19. Removal of cesium from aluminum decladding wastes generated in irradiated target processing using a fixed-bed column of resorcinol-formaldehyde resin

    International Nuclear Information System (INIS)

    Brunson, R.R.; Williams, D.F.; Bond, W.D.; Benker, D.E.; Chattin, F.R.; Collins, E.D.

    1994-09-01

    The removal of cesium (Cs) from a low-level liquid waste (LLLW) with a cation-exchange column was demonstrated using a resorcinol-formaldehyde (RF) resin. The RF resin was developed at the Westinghouse Savannah River Laboratory (SRL) and is highly specific for the removal of Cs from an alkaline waste of high sodium content. It was determined that the RF resin would be suitable for removing Cs, the largest gamma radiation contributor, from the LLLW generated at the Radiochemical Engineering Development Center located at the Oak Ridge National Laboratory. Presently, the disposal of the LLLW is limited due to the amount of Cs contained in the waste. Cesium removal from the waste solution offers immediate benefits by conserving valuable tank space and would allow cask shipments of the treated waste should the present Laboratory pipelines become unavailable in the future. Preliminary laboratory tests of the RF resins, supplied from two different sources, were used to design a full-scale cation-exchange column for the removal of Cs from a Mark 42 SRL fuel element dejacketing waste solution. The in-cell tests reproduced the preliminary bench-scale test results. The initial Cs breakthrough range was 85--92 column volumes (CV). The resin capacity for Cs was found to be ∼0.35 meq per gram of resin. A 1.5-liter resin bed loaded a combined ∼1,300 Ci of 134 Cs and 137 Cs. A distribution coefficient of ∼110 CV was determined, based on a 50% Cs breakthrough point. The kinetics of the system was studied by examining the rate parameters; however, it was decided that several more tests would be necessary to define the mass transfer characteristics of the system

  20. Selective determination of thorium in water using dual-wavelength β-correction spectrophotometry and the reagent 4-(2-pyridylazo)-resorcinol

    International Nuclear Information System (INIS)

    Kadi, M.W.; El-Shahawi, M.S.

    2011-01-01

    A simple, fast, low cost, and precise direct β-correction spectrophotometric method was developed for thorium determination in water. The method is based on the reaction of Th(IV) with 4-(2-pyridylazo)-resorcinol (PAR) in aqueous solution of pH 5-6 and measuring the absorbance of the resulting red-colored complex at λ max 497 nm. The effective molar absorptivity of the Th(IV)-PAR complex was 2.52 x 10 4 L mol -1 cm -1 . Beer's law and Ringbom plots were obeyed in the concentration range 0.04-2.0 and 0.07-1.2 μg mL -1 of thorium ions using β-correction spectrophotometry, respectively. The limits of detection and quantification of Th(IV) were 0.02 and 0.066 μg mL -1 , respectively. The developed method was applied for the analysis of thorium in certified reference material (IAEA-soil-7), tap-, underground- and Red-sea water samples. The validation of the method was also tested by comparison with data obtained by ICP-MS. The method is convenient, less sensitive to common interfering species and less laborious than most of published methods. The statistical treatment of data in terms of Student t-tests and variance ratio f-tests has revealed no significance differences. The structure of the Th(IV)-PAR complex was determined with the aid of spectroscopic measurements (UV-Visible and Fourier Transform Infrared Spectroscopy). (author)

  1. A novel sulfonated poly(ether ether ketone) and cross-linked membranes for fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hongtao; Zhang, Gang; Wu, Jing; Zhao, Chengji; Zhang, Yang; Shao, Ke; Han, Miaomiao; Lin, Haidan; Zhu, Jing; Na, Hui [Alan G MacDiarmid Institute, College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, Jilin (China)

    2010-10-01

    A novel poly(ether ether ketone) (PEEK) containing pendant carboxyl groups has been synthesized by a nucleophilic polycondensation reaction. Sulfonated polymers (SPEEKs) with different ion exchange capacity are then obtained by post-sulfonation process. The structures of PEEK and SPEEKs are characterized by both FT-IR and {sup 1}H NMR. The properties of SPEEKs as candidates for proton exchange membranes are studied. The cross-linking reaction is performed at 140 C using poly(vinyl alcohol) (PVA) as the cross-linker. In comparison with the non-cross-linked membranes, some properties of the cross-linked membranes are significantly improved, such as water uptake, methanol resistance, mechanical and oxidative stabilities, while the proton conductivity decreases. The effect of PVA content on proton conductivity, water uptake, swelling ratio, and methanol permeability is also investigated. Among all the membranes, SPEEK-C-8 shows the highest selectivity of 50.5 x 10{sup 4} S s cm{sup -3}, which indicates that it is a suitable candidate for applications in direct methanol fuel cells. (author)

  2. Rheological, mechanical and tribological properties of carbon-nanofibre reinforced poly (ether ether ketone composites

    Directory of Open Access Journals (Sweden)

    Volker Altstaedt

    2003-12-01

    Full Text Available Poly(ether ether ketone nanocomposites containing vapour-grown carbon nanofibres (CNF were produced using standard polymer processing techniques. At high shear rates no significant increase in resin viscosity was observed. Nevertheless, the addition of the CNFs results in a higher melt strength at 360°C. Electron microscopy confirmed the homogeneous dispersion and alignment of nanofibres in the polymer matrix. Evaluation of the mechanical composite properties revealed a linear increase in tensile stiffness and strength with nanofibre loading fractions up to 15 wt% whilst matrix ductility was maintained up to 10 wt%. An interpretation of the composite performance by short-fibre theory resulted in rather low intrinsic stiffness properties of the vapour-grown CNF. Differential scanning calorimetry was used to investigate crystallization kinetics and degree of crystallinity. The CNFs were found not to act as nucleating sites. Furthermore, unidirectional sliding tests against two different counterpart materials (100Cr6 martensitic bearing steel, X5CrNi18-10 austenitic stainless steel were performed. The carbon nanofibres were found to reduce the wear rate of PEEK significantly.

  3. An improved synthesis process of calixcrown ethers and synthesis of novel calixcrown ether

    International Nuclear Information System (INIS)

    Wang Hairong; Zhang Ping; Wang Chunmiao; Wang Jianchen; Chen Jing

    2007-01-01

    The synthesis method of calixcrown ethers was simplified and improved, and 10 L- scale synthesis was carried out. In the synthesis of the intermediates of the first three steps, the synthesis of 5, 11, 17, 23-tetra-tert-butyl-25, 26, 27, 28-tetrahydroxyl-calix[4] and its dehydroxylation were considered together, the purification procedures of the former, including re-crystallization in toluene and decolorization with activated carbon, were cancelled, and thus these steps were simplified. In the synthesis of oligoethylene glycol ditosylate, the purification method was also improved and the time-consuming column chromatography was left out. In the final step, impurities were removed by repeating stirring-settlement steps, by following recrystallization, the pure product was obtained. With these measures, the whole process could be implemented easily. The industrial scale production of calixcrown ethers could be fulfilled with the improved process. In addition, a new extracant, 25, 27-bis (n-propyloxy)calix[4]-26, 28-crown-6, is prepared and identified. (authors)

  4. Development and characterization of poli composites (ether ether ketone)(PEEK)(Hydroxyapatite(HA)

    International Nuclear Information System (INIS)

    Ferreira, V.P.; Santos, F.S.F.; Sa, M.D. de; Fook, M.V.L.

    2016-01-01

    The objective of this work was to develop PEEK / HA composites, combining the biological activity of the ceramic phase with the properties of the polymer phase, the materials used in this research were Poly (ether-ether-ketone) (PEEK) and Hydroxyapatite (HA) (50, 60, 70 and 80% m / v HA), this material was subjected to a load of two tons followed by a thermal treatment at 390 ° for a period of 30 minutes. Then they were characterized by FTIR, DRX and MO. In the physical-chemical characterization of FTIR and XRD, it was not possible to identify significant alterations. In the FTIR spectra of the composites, there is no formation of new identifiable chemical bonds. In the composites XRD diffractograms a profile similar to the ceramic phase was observed, with peaks increasing in intensity and narrowing proportional to the increase of the hydroxyapatite concentration in the composites. In optical microscopy it is possible to observe surfaces with heterogeneous morphology, with signs of roughness and in the cross section we observe a heterogeneous aspect, rich in regions with large agglomerates and lighter particles. Considering the processing aspects, the technique proved to be effective for the development of PEEK /HA composites. (author)

  5. Enhanced osteoblast responses to poly ether ether ketone surface modified by water plasma immersion ion implantation.

    Science.gov (United States)

    Wang, Heying; Lu, Tao; Meng, Fanhao; Zhu, Hongqin; Liu, Xuanyong

    2014-05-01

    Poly ether ether ketone (PEEK) offers a set of characteristics superior for human implants; however, its application is limited by the bio-inert surface property. In this work, PEEK surface was modified using single step plasma immersion ion implantation (PIII) treatment with a gas mixture of water vapor as a plasma resource and argon as an ionization assistant. Field emission scanning electron microscopy, atomic force microscopy and X-ray photoelectron spectroscopy were used to investigate the microstructure and composition of the modified PEEK surface. The water contact angle and zeta-potential of the surfaces were also measured. Osteoblast precursor cells MC3T3-E1 and rat bone mesenchymal stem cells were cultured on the PEEK samples to evaluate their cytocompatibility. The obtained results show that the hydroxyl groups as well as a "ravined structure" are constructed on water PIII modified PEEK. Compared with pristine PEEK, the water PIII treated PEEK is more favorable for osteoblast adhesion, spreading and proliferation, besides, early osteogenic differentiation indicated by the alkaline phosphatase activity is also up-regulated. Our study illustrates enhanced osteoblast responses to the PEEK surface modified by water PIII, which gives positive information in terms of future biomedical applications. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Radiolabeled cholesteryl ethers: A need to analyze for biological stability before use

    Directory of Open Access Journals (Sweden)

    Denny Joseph Manual Kollareth

    2018-03-01

    Full Text Available Radiolabeled cholesteryl ethers are widely used as non-metabolizable tracers for lipoproteins and lipid emulsions in a variety of in vitro and in vivo experiments. Since cholesteryl ethers do not leave cells after uptake and are not hydrolyzed by mammalian cellular enzymes, these compounds can act as markers for cumulative cell uptakes of labeled particles. We have employed [3H]cholesteryl oleoyl ether to study the uptake and distribution of triglyceride-rich emulsion particles on animal models. However, questionable unexpected results compelled us to analyze the stability of these ethers. We tested the stability of two commercially available radiolabeled cholesteryl ethers - [3H]cholesteryl oleoyl ether and [3H]cholesteryl hexadecyl ether from different suppliers, employing in vitro, in vivo and chemical model systems. Our results show that, among the two cholesteryl ethers tested, one ether was hydrolyzed to free cholesterol in vitro, in vivo and chemically under alkaline hydrolyzing agent. Free cholesterol, unlike cholesteryl ether, can then re-enter the circulation leading to confounding results. The other ether was not hydrolyzed to free cholesterol and remained as a stable ether. Hence, radiolabeled cholesteryl ethers should be analyzed for biological stability before utilizing them for in vitro or in vivo experiments. Keywords: Cholesteryl ether, J774 A2 macrophages, Soy oil emulsion, Thin layer chromatography, triDHA emulsion

  7. α-Diazo oxime ethers for N-heterocycle synthesis.

    Science.gov (United States)

    Choi, Subin; Ha, Sujin; Park, Cheol-Min

    2017-06-01

    This Feature Article introduces the preparation and synthetic utility of α-diazo oxime ethers. α-Oximino carbenes are useful synthons for N-heterocycles, and can be easily prepared from α-diazo oxime ethers as precursors. We begin with the preparation of α-diazo oxime ethers and their application in [3+2] cycloaddition. It turns out that the nature of metals bound to carbenes plays a crucial role in modulating the reactivity of α-oximino carbenes, in which copper carbenes smoothly react with enamines, whereas the less reactive enol ethers and nitriles require gold carbenes. In Section 3.2, a discussion on N-O and C-H bond activation is presented. Carbenes derived from diazo oxime ethers show unique reactivity towards N-O and C-H bond activation, in which the proximity of the two functionalities, carbene and oxime ether, dictates the preferred reaction pathways toward pyridines, pyrroles, and 2H-azirines. In Section 3.3, the development of tandem reactions based on α-diazo oxime ethers is discussed. The nature of carbenes in which whether free carbenes or metal complexes are involved dissects the pathway and forms different types of 2H-azirines. The 2H-azirine formation turned out to be an excellent platform for the tandem synthesis of N-heterocycles including pyrroles and pyridines. In the last section, we describe the electrophilic activation of 2H-azirines with vinyl carbenes and oximino carbenes. The resulting azirinium species undergo rapid ring expansion rearrangements to form pyridines and pyrazines.

  8. Formation of trihalomethanes from the halogenation of 1,3-dihydroxybenzenes in dilute aqueous solution: synthesis of 2-13C-resorcinol and its reaction with chlorine and bromine

    International Nuclear Information System (INIS)

    Boyce, S.D.; Barefoot, A.C.; Britton, D.R.; Hornig, J.F.

    1983-01-01

    As part of this study, the reaction of bromine with resorcinol and structurally related substrates to produce bromoform was examined. Preliminary results suggest that the chlorination and bromination of dihydroxybenzenes proceeded by similar reaction pathways. This chapter describes the successful synthesis of 2- 13 C-1, 3-dihydroxybenzene. Treatment of the isotopically labelled substrate with chlorine and bromine in dilute aqueous solution has elucidated many important details of the sequence of reactions leading to the production of chloroform (CHCl 3 ) and bromoform (CHBr 3 ). The 13 C-enriched products and intermediates formed during these reactions were identified by gas chromatography/mass spectrometry

  9. High pressure injection of dimethyl ether

    Energy Technology Data Exchange (ETDEWEB)

    Glensvig, M.; Sorenson, S.C.; Abata, D.L.

    1997-08-01

    The purpose of this investigation was to achieve a better understanding of the fundamental spray behavior of DME (Dimenthyl Ether) using a standard diesel pump with pintle and hole nozzles. Fundamental spray behavior was characterized by determining fuel spray penetration and angle, atomization and evaporation. The influences of opening pressure, nozzle geometry and ambient pressure above and below the critical pressure of the fuel on the spray behavior were investigated. The influence of opening pressures on the spray characteristics for the hole nozzle was investigated. The results showed that for opening pressures of 120 bar and 180 bar the spray has a similar appearance. For the higher opening pressure (200 bar and 240 bar), the initial spray breaks up very rapidly giving a high initial spray angle. The opening pressure had little influence on spray penetration. The spray angle later in the injection increased as the opening pressure was decreased. Above the critical pressure, the spray from the hole nozzle had a more irregular shape. Penetration decreased and the spray angle increased above the critical pressure. Three pintle nozzles with different geometries and opening pressures were tested. The appearance of the three sprays were very similar. The sprays seemed to be more sharply pointed as the nozzle hole angle decreased. The nozzle with the 4 deg. hole nozzle angle and an opening pressure of 280 bar had the highest penetration and highest initial spray angle. The pintle nozzle with the 12 deg. hole nozzle angle and opening pressure of approx. 450 bar was tested above the critical ambient pressure. Penetration was very similar for injection above and below the critical ambient pressure, while the spray angle decreased for the spray above the critical ambient pressure. (au)

  10. Mutagenicity testing of diethylene glycol monobutyl ether.

    Science.gov (United States)

    Thompson, E D; Coppinger, W J; Valencia, R; Iavicoli, J

    1984-01-01

    The mutagenic potential of diethylene glycol monobutyl ether (diEGBE) was examined with a Tier I battery of in vitro assays followed by a Tier II in vivo Drosophila sex-linked recessive lethal assay. The in vitro battery consisted of: the Salmonella mutagenicity test, the L5178Y mouse lymphoma test, a cytogenetics assay using Chinese hamster ovary cells and the unscheduled DNA synthesis (UDS) assay in rat hepatocytes. Results of the Salmonella mutagenicity test, the cytogenetics test, and the rat hepatocyte assay were negative at concentrations up to 20 microL/plate, 7.92 microL/mL, and 4.4 microL/mL, respectively. Toxicity was clearly demonstrated at all high doses. A weak, but dose-related increase in the mutation frequency (4-fold increase over the solvent control at 5.6 microL/mL with 12% survival) was obtained in the L5178Y lymphoma test in the absence of metabolic activation. Results of the mouse lymphoma assay were negative in the presence of the S-9 activation system. The significance of the mouse lymphoma assay were negative in the presence of the S-9 activation system. The significance of the mouse lymphoma assay results were assessed by performing the Tier II sex-linked recessive lethal assay in Drosophila in which the target tissue is maturing germinal cells. Both feeding (11,000 ppm for 3 days) and injection (0.3 microL of approximately 14,000 ppm solution) routes of administration were employed in the Drosophila assay. Approximately 11,000 individual crosses with an equal number of negative controls were performed for each route of administration. diEGBE produced no increase in recessive lethals under these conditions.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6389113

  11. On the ether-like Lorentz-breaking actions

    International Nuclear Information System (INIS)

    Petrov, A.Yu; Nascimento, J.R.; Gomes, M.; Silva, A. J. da

    2011-01-01

    We demonstrate the generation of the CPT-even, ether-like Lorentz-breaking actions for the scalar and electro-magnetic fields via their appropriate Lorentz-breaking coupling to spinor fields in three, four and five space-time dimensions. Besides, we show that the ether-like terms for the spinor field also can be generated as a consequence of the same couplings. The key result which will be presented here is the finiteness of the ether-like term for the electromagnetic field not only in three and five space-time dimensions where it is natural due to known effects of the dimensional regularization but also in four space-time dimensions. Moreover, we present the calculation of the last result within different calculational schemes and conclude that the result for the four-dimensional ether-like term for the electromagnetic field essentially depending on the calculation scheme, similarly to the result for the Carroll-Field-Jackiw (CFJ) term which probably signalizes a possibility for arising of a new anomaly. Also we discuss the dispersion relations in the theories with ether-like Lorentz-breaking terms which allows to discuss the consistency of the Lorentz-breaking modified theories for different (space-like or time-like) Lorentz-breaking vectors and find the tree-level effective (Breit) potential for fermion scattering and the one-loop effective potential corresponding to the action of the scalar field. (author)

  12. Radiolabeled cholesteryl ethers: A need to analyze for biological stability before use.

    Science.gov (United States)

    Manual Kollareth, Denny Joseph; Chang, Chuchun L; Hansen, Inge H; Deckelbaum, Richard J

    2018-03-01

    Radiolabeled cholesteryl ethers are widely used as non-metabolizable tracers for lipoproteins and lipid emulsions in a variety of in vitro and in vivo experiments. Since cholesteryl ethers do not leave cells after uptake and are not hydrolyzed by mammalian cellular enzymes, these compounds can act as markers for cumulative cell uptakes of labeled particles. We have employed [ 3 H]cholesteryl oleoyl ether to study the uptake and distribution of triglyceride-rich emulsion particles on animal models. However, questionable unexpected results compelled us to analyze the stability of these ethers. We tested the stability of two commercially available radiolabeled cholesteryl ethers - [ 3 H]cholesteryl oleoyl ether and [ 3 H]cholesteryl hexadecyl ether from different suppliers, employing in vitro , in vivo and chemical model systems. Our results show that, among the two cholesteryl ethers tested, one ether was hydrolyzed to free cholesterol in vitro , in vivo and chemically under alkaline hydrolyzing agent. Free cholesterol, unlike cholesteryl ether, can then re-enter the circulation leading to confounding results. The other ether was not hydrolyzed to free cholesterol and remained as a stable ether. Hence, radiolabeled cholesteryl ethers should be analyzed for biological stability before utilizing them for in vitro or in vivo experiments.

  13. Mechanical Properties Optimization of Poly-Ether-Ether-Ketone via Fused Deposition Modeling

    Directory of Open Access Journals (Sweden)

    Xiaohu Deng

    2018-01-01

    Full Text Available Compared to the common selective laser sintering (SLS manufacturing method, fused deposition modeling (FDM seems to be an economical and efficient three-dimensional (3D printing method for high temperature polymer materials in medical applications. In this work, a customized FDM system was developed for polyether-ether-ketone (PEEK materials printing. The effects of printing speed, layer thickness, printing temperature and filling ratio on tensile properties were analyzed by the orthogonal test of four factors and three levels. Optimal tensile properties of the PEEK specimens were observed at a printing speed of 60 mm/s, layer thickness of 0.2 mm, temperature of 370 °C and filling ratio of 40%. Furthermore, the impact and bending tests were conducted under optimized conditions and the results demonstrated that the printed PEEK specimens have appropriate mechanical properties.

  14. Mechanical Properties Optimization of Poly-Ether-Ether-Ketone via Fused Deposition Modeling.

    Science.gov (United States)

    Deng, Xiaohu; Zeng, Zhi; Peng, Bei; Yan, Shuo; Ke, Wenchao

    2018-01-30

    Compared to the common selective laser sintering (SLS) manufacturing method, fused deposition modeling (FDM) seems to be an economical and efficient three-dimensional (3D) printing method for high temperature polymer materials in medical applications. In this work, a customized FDM system was developed for polyether-ether-ketone (PEEK) materials printing. The effects of printing speed, layer thickness, printing temperature and filling ratio on tensile properties were analyzed by the orthogonal test of four factors and three levels. Optimal tensile properties of the PEEK specimens were observed at a printing speed of 60 mm/s, layer thickness of 0.2 mm, temperature of 370 °C and filling ratio of 40%. Furthermore, the impact and bending tests were conducted under optimized conditions and the results demonstrated that the printed PEEK specimens have appropriate mechanical properties.

  15. Biofilm behavior on sulfonated poly(ether-ether-ketone) (sPEEK)

    International Nuclear Information System (INIS)

    Montero, Juan F.D.; Tajiri, Henrique A.; Barra, Guilherme M.O.; Fredel, Márcio C.; Benfatti, Cesar A.M.; Magini, Ricardo S.; Pimenta, Andréa L.; Souza, Júlio C.M.

    2017-01-01

    Poly(ether-ether-ketone) (PEEK) has also shown to be very attractive for incorporating therapeutic compounds thanks to a sulfonation process which modifies the material structure resulting in a sulfonated-PEEK (sPEEK). Concerning biomedical applications, the objective of this work was to evaluate the influence of different sulfonation degree of sPEEK on the biofilm growth. PEEK samples were functionalized by using sulphuric acid (98%) and then dissolved into dimethyl-sulfoxide. A dip coating technique was used to synthesize sPEEK thin films. The sulfonation degree of the materials was analyzed by FT-IR, H NMR, TG and IEC. The surfaces were characterized by scanning electron microscopy, profilometry and contact angle analyses. Subsequently, the biofilm formation on sulfonated-PEEK based on Streptococcus mutans and Enterococcus faecalis was measured by spectrophotometry, colony forming units (CFU mL −1 ) and SEM. Results obtained from thermal and chemical analyses showed an intensification in sulfonation degree for sPEEK at 2 and 2.5 h. The E. faecalis or S. mutans biofilm growth revealed statistically significant differences (p < 0.05) between 2 and 3 h sulfonation groups. A significant decrease (p < 0.05) in CFU mL −1 was recorded for S. mutans or E. faecalis biofilm grown on 2.5 or 3 h sPEEK. Regarding the thermal-chemical and microbiologic analyses, the sulfonation degree of sPEEK ranging from 2 up to 3 h was successful capable to decrease the biofilm growth. That revealed an alternative strategy to embed anti-biofilm and therapeutic compounds into PEEK avoiding infections in biomedical applications. - Highlights: • PEEK can be dissolved to incorporate therapeutic compounds. • High sulfonation degree on sPEEK affected the biofilm growth. • The sulfonation degree must be controlled to maintain the properties of sPEEK.

  16. Biofilm behavior on sulfonated poly(ether-ether-ketone) (sPEEK)

    Energy Technology Data Exchange (ETDEWEB)

    Montero, Juan F.D. [Center for Research on Dental Implants (CEPID), School of Dentistry (ODT), Federal University of Santa Catarina - UFSC, Florianópolis, SC 88040-900 (Brazil); Tajiri, Henrique A.; Barra, Guilherme M.O.; Fredel, Márcio C. [Department of Mechanical Engineering (EMC), Federal University of Santa Catarina (UFSC), Florianópolis, SC 88040-900 (Brazil); Benfatti, Cesar A.M.; Magini, Ricardo S. [Center for Research on Dental Implants (CEPID), School of Dentistry (ODT), Federal University of Santa Catarina - UFSC, Florianópolis, SC 88040-900 (Brazil); Pimenta, Andréa L. [Integrated Laboratories Technologies (InteLAB), Dept. Chemical Engineering (EQA), Federal University of Santa Catarina - UFSC, Florianópolis, SC 88040-970 (Brazil); Department of Biologie, Université de Cergy Pontoise, 2, Av. Adolphe Chauvin, 95302 Cergy Pontoise (France); Souza, Júlio C.M., E-mail: julio.c.m.souza@ufsc.br [Center for Research on Dental Implants (CEPID), School of Dentistry (ODT), Federal University of Santa Catarina - UFSC, Florianópolis, SC 88040-900 (Brazil); Center for Microelectromechanical Systems (CMEMS), Dept. Mechanical Engineering (DEM), Campus Azurém, 4800-058 Guimarães (Portugal)

    2017-01-01

    Poly(ether-ether-ketone) (PEEK) has also shown to be very attractive for incorporating therapeutic compounds thanks to a sulfonation process which modifies the material structure resulting in a sulfonated-PEEK (sPEEK). Concerning biomedical applications, the objective of this work was to evaluate the influence of different sulfonation degree of sPEEK on the biofilm growth. PEEK samples were functionalized by using sulphuric acid (98%) and then dissolved into dimethyl-sulfoxide. A dip coating technique was used to synthesize sPEEK thin films. The sulfonation degree of the materials was analyzed by FT-IR, H NMR, TG and IEC. The surfaces were characterized by scanning electron microscopy, profilometry and contact angle analyses. Subsequently, the biofilm formation on sulfonated-PEEK based on Streptococcus mutans and Enterococcus faecalis was measured by spectrophotometry, colony forming units (CFU mL{sup −1}) and SEM. Results obtained from thermal and chemical analyses showed an intensification in sulfonation degree for sPEEK at 2 and 2.5 h. The E. faecalis or S. mutans biofilm growth revealed statistically significant differences (p < 0.05) between 2 and 3 h sulfonation groups. A significant decrease (p < 0.05) in CFU mL{sup −1} was recorded for S. mutans or E. faecalis biofilm grown on 2.5 or 3 h sPEEK. Regarding the thermal-chemical and microbiologic analyses, the sulfonation degree of sPEEK ranging from 2 up to 3 h was successful capable to decrease the biofilm growth. That revealed an alternative strategy to embed anti-biofilm and therapeutic compounds into PEEK avoiding infections in biomedical applications. - Highlights: • PEEK can be dissolved to incorporate therapeutic compounds. • High sulfonation degree on sPEEK affected the biofilm growth. • The sulfonation degree must be controlled to maintain the properties of sPEEK.

  17. Fuel cell performance of pendent methylphenyl sulfonated poly(ether ether ketone ketone)s

    Science.gov (United States)

    Zhang, Hanyu; Stanis, Ronald J.; Song, Yang; Hu, Wei; Cornelius, Chris J.; Shi, Qiang; Liu, Baijun; Guiver, Michael D.

    2017-11-01

    Meta- and para-linked homopolymers bearing 3-methylphenyl (Me) pendent groups were postsulfonated to create sulfonated poly(ether ether ketone ketone) (SPEEKK) backbone isomers, which are referred to as Me-p-SPEEKK and Me-m-SPEEKK. Their thermal and oxidative stability, mechanical properties, dimensional stability, methanol permeability, and proton conductivity are characterized. Me-p-SPEEKK and Me-m-SPEEKK proton conductivities at 100 °C are 116 and 173 mS cm-1, respectively. Their methanol permeabilities are 3.3-3.9 × 10-7 cm2 s-1, and dimensional swelling at 100 °C is 16.4-17.5%. Me-p-SPEEKK and Me-m-SPEEKK were fabricated into membrane electrode assemblies (MEAs), and electrochemical properties were evaluated within a direct methanol fuel cell (DMFC) and proton-exchange membrane fuel cell (PEMFC). When O2 is used as the oxidant at 80 °C and 100% RH, the maximum power density of Me-m-SPEEKK reaches 657 mW cm-2, which is higher than those of Nafion 115 (552 mW cm-2). DMFC performance is 85 mW cm-2 at 80 °C with 2.0 M methanol using Me-p-SPEEKK due to its low MeOH crossover. In general, these electrochemical results are comparable to Nafion. These ionomer properties, combined with a potentially less expensive and scalable polymer manufacturing process, may broaden their potential for many practical applications.

  18. Stress shielding and fatigue limits of poly-ether-ether-ketone dental implants.

    Science.gov (United States)

    Lee, Woo-Taek; Koak, Jai-Young; Lim, Young-Jun; Kim, Seong-Kyun; Kwon, Ho-Beom; Kim, Myung-Joo

    2012-05-01

    The poly-ether-ether-ketone (PEEK) polymer is of great interest as an alternative to titanium in orthopedics because of its biocompatibility and low elastic modulus. This study evaluated the fatigue limits of PEEK and the effects of the low elastic modulus PEEK in relation to existing dental implants. Compressive loading tests were performed with glass fiber-reinforced PEEK (GFR-PEEK), carbon fiber-reinforced PEEK (CFR-PEEK), and titanium rods. Among these tests, GFR-PEEK fatigue tests were performed according to ISO 14801. For the finite element analysis, three-dimensional models of dental implants and bone were constructed. The implants in the test groups were coated with a 0.5-mm thick and 5-mm long PEEK layer on the upper intrabony area. The strain energy densities (SED) were calculated, and the bone resorption was predicted. The fatigue limits of GFR-PEEK were 310 N and were higher than the static compressive strength of GFR-PEEK. The bone around PEEK-coated implants showed higher levels of SED than the bone in direct contact with the implants, and the wider diameter and stiffer implants showed lower levels of SED. The compressive strength of the GFR-PEEK and CFR-PEEK implants ranged within the bite force of the anterior and posterior dentitions, respectively, and the PEEK implants showed adequate fatigue limits for replacing the anterior teeth. Dental implants with PEEK coatings and PEEK implants may reduce stress shielding effects. Dental implant application of PEEK polymer-fatigue limit and stress shielding. Copyright © 2012 Wiley Periodicals, Inc.

  19. Spontaneous Generation of Chirality in Simple Diaryl Ethers.

    Science.gov (United States)

    Lennartson, Anders; Hedström, Anna; Håkansson, Mikael

    2015-07-01

    We studied the spontaneous formation of chiral crystals of four diaryl ethers, 3-phenoxybenzaldehyde, 1; 1,3-dimethyl-2-phenoxybenzene, 2; di(4-aminophenyl) ether, 3; and di(p-tolyl) ether, 4. Compounds 1, 3, and 4 form conformationally chiral molecules in the solid state, while the chirality of 2 arises from the formation of supramolecular helices. Compound 1 is a liquid at ambient temperature, but 2-4 are crystalline, and solid-state CD-spectroscopy showed that they could be obtained as optically active bulk samples. It should be noted that the optical activity arise upon crystallization, and no optically active precursors were used. Indeed, even commercial samples of 3 and 4 were found to be optically active, giving evidence for the ease at which total spontaneous resolution may occur in certain systems. © 2015 Wiley Periodicals, Inc.

  20. Enzymatic network for production of ether amines from alcohols

    DEFF Research Database (Denmark)

    Palacio, Cyntia M.; Crismaru, Ciprian G.; Bartsch, Sebastian

    2016-01-01

    We constructed an enzymatic network composed of three different enzymes for the synthesis of valuable ether amines. The enzymatic reactions are interconnected to catalyze the oxidation and subsequent transamination of the substrate and to provide cofactor recycling. This allows production...... of the desired ether amines from the corresponding ether alcohols with inorganic ammonium as the only additional substrate. To examine conversion, individual and overall reaction equilibria were established. Using these data, it was found that the experimentally observed conversions of up to 60% observed...... for reactions containing 10mM alcohol and up to 280mM ammonia corresponded well to predicted conversions. The results indicate that efficient amination can be driven by high concentrations of ammonia and may require improving enzyme robustness for scale-up....

  1. Role of hydrogen-bonding and photoinduced electron transfer (PET) on the interaction of resorcinol based acridinedione dyes with Bovine Serum Albumin (BSA) in water

    International Nuclear Information System (INIS)

    Kumaran, Rajendran; Vanjinathan, Mahalingam; Ramamurthy, Perumal

    2015-01-01

    Resorcinol based acridinedione (ADDR) dyes are a class of laser dyes and have structural similarity with purine derivatives, nicotinamide adenine dinucleotide (NADH) analogs. These dyes are classified into photoinduced electron transfer (PET) and non-photoinduced electron transfer dyes, and the photophysical properties of family of these dyes exhibiting PET behavior are entirely different from that of non-PET dyes. The PET process in ADDR dyes is governed by the solvent polarity such that an ADDR dye exhibits PET process through space in an aprotic solvent like acetonitrile and does not exhibit the same in protic solvents like water and methanol. A comparison on the fluorescence emission, lifetime and nature of interaction of various ADDR dyes with a large globular protein like Bovine Serum Albumin (BSA) was carried out in aqueous solution. The interaction of PET based ADDR dyes with BSA in water is found to be largely hydrophobic, but hydrogen-bonding interaction of BSA with dye molecule influences the fluorescence emission of the dye and shifts the emission towards red region. Fluorescence spectral studies reveal that the excited state properties of PET based ADDR dyes are largely influenced by the addition of BSA. The microenvironment around the dye results in significant change in the fluorescence lifetime and emission. Fluorescence enhancement with a red shift in the emission results after the addition of BSA to ADDR dyes containing free amino hydrogen in the 10th position of basic acridinedione dye. The amino hydrogen (N–H) in the 10th position of ADDR dye is replaced by methyl group (N–CH 3 ), a significant decrease in the fluorescence intensity with no apparent shift in the emission maximum was observed after the addition of BSA. The nature of interaction between ADDR dyes with BSA is hydrogen-bonding and the dye remains unbound even at the highest concentration of BSA. Circular Dichroism (CD) studies show that the addition of dye to BSA results in a

  2. Radiation-induced glycoside bond breaking in cellulose methyl ethers

    International Nuclear Information System (INIS)

    Petryaev, E.P.; Boltromeyuk, V.V.; Kovalenko, N.I.; Shadyro, O.I.

    1988-01-01

    Radiation-induced destruction of cellulose methyl ethers of different degree of esterification in aqueous solutions with and without acceptors: (N 2 O, O 2 , H 2 O + , Co(2), Cu(2)) is investigated. It is established that OH radicals make main contribution into radiolytic transformations of cellulose ethers in aqueous solutions. Reactions of radicals with free valency on carbon atoms containing secondary nonsubstituted hydroxyl groups lead also to glycoside bond breaking besides the reaction of β-fragmentation and hydrolysis of radicals with an unpaired electron localized near C 1 , C 4 , C 5 aroms

  3. Environmental analysis of higher brominated diphenyl ethers and decabromodiphenyl ethane.

    Science.gov (United States)

    Kierkegaard, Amelie; Sellström, Ulla; McLachlan, Michael S

    2009-01-16

    Methods for environmental analysis of higher brominated diphenyl ethers (PBDEs), in particular decabromodiphenyl ether (BDE209), and the recently discovered environmental contaminant decabromodiphenyl ethane (deBDethane) are reviewed. The extensive literature on analysis of BDE209 has identified several critical issues, including contamination of the sample, degradation of the analyte during sample preparation and GC analysis, and the selection of appropriate detection methods and surrogate standards. The limited experience with the analysis of deBDethane suggests that there are many commonalities with BDE209. The experience garnered from the analysis of BDE209 over the last 15 years will greatly facilitate progress in the analysis of deBDethane.

  4. Molecular structure impacts on secondary organic aerosol formation from glycol ethers

    Science.gov (United States)

    Li, Lijie; Cocker, David R.

    2018-05-01

    Glycol ethers, a class of widely used solvents in consumer products, are often considered exempt as volatile organic compounds based on their vapor pressure or boiling points by regulatory agencies. However, recent studies found that glycol ethers volatilize at ambient conditions nearly as rapidly as the traditional high-volatility solvents indicating the potential of glycol ethers to form secondary organic aerosol (SOA). This is the first work on SOA formation from glycol ethers. The impact of molecular structure, specifically -OH, on SOA formation from glycol ethers and related ethers are investigated in the work. Ethers with and without -OH, with methyl group hindrance on -OH and with -OH at different location are studied in the presence of NOX and under "NOX free" conditions. Photooxidation experiments under different oxidation conditions confirm that the processing of ethers is a combination of carbonyl formation, cyclization and fragmentation. Bulk SOA chemical composition analysis and oxidation products identified in both gas and particle phase suggests that the presence and location of -OH in the carbon bond of ethers determine the occurrence of cyclization mechanism during ether oxidation. The cyclization is proposed as a critical SOA formation mechanism to prevent the formation of volatile compounds from fragmentation during the oxidation of ethers. Glycol ethers with -CH2-O-CH2CH2OH structure is found to readily form cyclization products, especially with the presence of NOx, which is more relevant to urban atmospheric conditions than without NOx. Glycol ethers are evaluated as dominating SOA precursors among all ethers studied. It is estimated that the contribution of glycol ethers to anthropogenic SOA is roughly 1% of the current organic aerosol from mobile sources. The contribution of glycol ethers to anthropogenic SOA is roughly 1% of the current organic aerosol from mobile sources and will play a more important role in future anthropogenic SOA

  5. High Resolution Rotational Spectroscopy of a Flexible Cyclic Ether

    Science.gov (United States)

    Gámez, F.; Martínez-Haya, B.; Blanco, S.; López, J. C.; Alonso, J. L.

    2011-06-01

    Crown ethers stand as one cornerstone molecular class inhost-guest Supramolecular Chemistry and constitute building blocks for a broad range of modern materials. We report here the first high resolution rotational study of a crown ether: 1,4,7,10,13-pentaoxacyclopentadecane (15-crown-5 ether,15c5). Molecular beam Fourier transform microwave spectroscopy has been employed. The liquid sample of 15c5 has been vaporized using heating methods. The considerable size of 15c5 and the broad range of conformations allowed by the flexibility of its backbone pose important challenges to spectroscopy approaches. In fact, the ab-initio computational study for isolated 15c5, yields at least six stable conformers with relative free energies within 2 kJ Mol-1 (167 Cm-1). Nevertheless, in this investigation it has been possible to identify and characterize in detail one stable rotamer of the 15c5 molecule and to challenge different quantum methods for the accurate description of this system. The results pave the ground for an extensive description of the conformational landscape of 15c5 and related cyclic ethers in the near term. J. L. Alonso, F. J. Lorenzo, J. C. López, A. Lesarri, S. Mata and H. Dreizler, Chem. Phys., 218, 267 (1997) S. Blanco, J.C López, J.L. Alonso, P. Ottaviani, W. Caminati, J. Chem. Phys. 119, 880 (2003) S.E. Hill, D. Feller, Int. J. Mass Spectrom. 201, 41 (2000)

  6. Direct transformation of silyl enol ethers into functionalized allenes.

    Science.gov (United States)

    Langer, P; Döring, M; Seyferth, D; Görls, H

    2001-02-02

    The first elimination reactions of silyl enol ethers to lithiated allenes are reported. These reactions allow a direct transformation of readily available silyl enol ethers into functionalized allenes. The action of three to four equivalents of lithium diisopropylamide (LDA) on silyl enol ethers results in the formation of lithiated allenes by initial allylic lithiation, subsequent elimination of a lithium silanolate, and finally, lithiation of the allene thus formed. Starting with amide-derived silyl imino ethers, lithiated ketenimines are obtained. A variety of reactions of the lithiated allenes with electrophiles (chlorosilanes, trimethylchlorostannane, dimethyl sulfate and ethanol) were carried out. Elimination of silanolate is observed only for substrates that contain the hindered SiMe2tBu or Si(iPr)3 moiety, but not for the SiMe3 group. The reaction of 1,1-dilithio-3,3-diphenylallene with ketones provides a convenient access to novel 1,1-di(hydroxymethyl)allenes which undergo a domino Nazarov-Friedel-Crafts reaction upon treatment with p-toluenesulfonic acid.

  7. Ether lipids of planktonic archae in the marine water column

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Hoefs, M.J.L.; Schouten, S.; King, L.L.; Wakeham, S.G.; Leeuw, J.W. de

    1997-01-01

    Acyclic and cyclic biphytanes derived from the membrane ether lipids of archaea were found in water column particulate and sedimentary organic matter from several oxic and anoxic marine environments. Compound-specific isotope analyses of the carbon skeletons suggest that planktonic archaea utilize

  8. Diethyl Ether Production as a Substitute for Gasoline

    Directory of Open Access Journals (Sweden)

    Alviany Riza

    2018-01-01

    Full Text Available Diethyl ether is one of alternative fuel that could be used as a significant component of a blend or as a complete replacement for transportation fuel. The aim of this research is to produce diethyl ether through dehydration reaction of ethanol with fixed bed reactor using nanocrystalline γ-Al2O3 catalyst. Nanocrystalline γ-Al2O3 catalyst was synthesized by precipitation method using Al(NO33.9H2O as precursors and NH4OH as the precipitating agent. Dehydration reaction was performed at temperature range of 125 to 225°C. The result shows that synthesized γ-Al2O3 catalyst gave higher ethanol conversion and diethyl ether yield than that of commercial Al2O3 catalyst. The use of synthesized γ-Al2O3 catalyst could reach ethanol conversion as high as 94.71% and diethyl ether yield as high as 11,29%.

  9. Diethyl Ether Production Process with Various Catalyst Type

    Directory of Open Access Journals (Sweden)

    Widayat Widayat

    2012-12-01

    Full Text Available Several H-zeolite and HZSM-5 catalysts was preparated and their characters have also been investigated. H-zeolit Catalyst was preparated from Natural Zeolite that obtained from Malang District and Gunung Kidul District. Diethyl ether was produced by Ethanol with concentration of 95%. This research use fixed bed reactor that 1 gram of catalyst as bed catalyst, atmospheric pressure and temperature 140oC as the operating condition. Ethanol vapor from vaporization tank was driven by 200 ml/min Nitrogen stream. The responds in this research is liquid product concentration; diethyl ether, ethanol, methanol and water concentration. The results showed that the largest ethanol conversion was produced by the use of 56.44% HZSM-5 and the largest yield of diethyl ether diethyl was produced by the use of alumina and H-zeolite catalyst. The larger ratio between natural zeolite with HCl solvent will produce the larger surface area of catalyst and ethanol conversion. The largest ethanol conversion was produced at reactan ratio 1:20. [Keywords:  catalyst; ethanol conversion; dehydration process; yield of diethyl ether; natural zeolite].

  10. Poly(ether ester amide)s for tissue engineering

    NARCIS (Netherlands)

    Deschamps, A.A.; van Apeldoorn, Aart A.; de Bruijn, Joost Dick; Grijpma, Dirk W.; Feijen, Jan

    2003-01-01

    Poly(ether ester amide) (PEEA) copolymers based on poly(ethylene glycol) (PEG), 1,4-butanediol and dimethyl-7,12-diaza-6,13-dione-1,18-octadecanedioate were evaluated as scaffold materials for tissue engineering. A PEEA copolymer based on PEG with a molecular weight of 300 g/mol and 25 wt% of soft

  11. Photodegradation of poly(ether sulphone). Part 2

    DEFF Research Database (Denmark)

    Norrman, K.; Krebs, Frederik C

    2004-01-01

    The photodegradation of poly(ether sulphone) (PES) was investigated systematically by time-of-flight SIMS (ToF-SIMS) and x-ray photoelectron spectroscopy (XPS). The effect of varying the irradiation dose, wavelength and the atmosphere was studied along with mechanistic photooxidation studies using...

  12. Radiation chemistry of alternative fuel oxygenates - substituted ethers

    International Nuclear Information System (INIS)

    Mezyk, S. P.; Cooper, W. J.; Bartels, D. M.; Tobien, T.; O'Shea, K. E.

    1999-01-01

    The electron beam process, an advanced oxidation and reduction technology, is based in the field of radiation chemistry. Fundamental to the development of treatment processes is an understanding of the underlying chemistry. The authors have previously evaluated the bimolecular rate constants for the reactions of methyl tert-butyl ether (MTBE) and with this study have extended their studies to include ethyl tert-butyl ether (ETBE), di-isopropyl ether (DIPE) and tert-amyl methyl ether (TAME) with the hydroxyl radical, hydrogen atom and solvated electron using pulse radiolysis. For all of the oxygenates the reaction with the hydroxyl radical appears to be of primary interest in the destruction of the compounds in water. The rates with the solvated electron are limiting values as the rates appear to be relatively low. The hydrogen atom rate constants are relatively low, coupled with the low yield in radiolysis, they concluded that these are of little significance in the destruction of the alternative fuel oxygenates (and MTBE)

  13. Dimethyl ether in diesel engines - progress and perspectives

    DEFF Research Database (Denmark)

    Sorenson, Spencer C

    2001-01-01

    A review of recent developments related to the use of dimethyl ether (DME) in engines is presented Research work discussed is in the areas of engine performance and emissions, fuel injection systems, spray and ignition delay, and detailed chemical kinetic modeling. DME's properties and safety asp...

  14. Formation and Structural Analysis of Novel Dibornyl Ethers | Kaye ...

    African Journals Online (AJOL)

    One- and two-dimensional NMR spectroscopy has been used to establish the regio- and stereochemistry of novel dibornyl ethers, obtained by acid-catalysed condensation of camphor-derived a-hydroxybornanones. South African Journal of Chemistry Vol.55 2002: 111-118 ...

  15. Enzymatic network for production of ether amines from alcohols

    NARCIS (Netherlands)

    Palacio, Cyntia M.; Crismaru, Gica Ciprian; Bartsch, Sebastian; Navickas, Vaidotas; Ditrich, Klaus; Breuer, Michael; Abu, Rohana; Woodley, John; Baldenius, Kai-Uwe; Wu, Bian; Janssen, Dick

    We constructed an enzymatic network composed of three different enzymes for the synthesis of valuable ether amines. The enzymatic reactions are interconnected to catalyze the oxidation and subsequent transamination of the substrate and to provide cofactor recycling. This allows production of the

  16. Ether and interpretation of some physical phenomena and concepts

    International Nuclear Information System (INIS)

    Rzayev, S.G.

    2008-01-01

    On the basis of the concept of existence of an ether representation about time, space, matters and physical field are profound and also the essence of such phenomena, as corpuscular - wave dualism, change of time, scale and mass at movement body's is opened. The opportunity of transition from probability-statistical interpretation of the quantum phenomena to Laplace's determinism is shown

  17. Basic randomness of nature and ether-drift experiments

    International Nuclear Information System (INIS)

    Consoli, M.; Pluchino, A.; Rapisarda, A.

    2011-01-01

    Highlights: ► We re-consider the idea of a basic randomness of nature. ► We adopt Stochastic Electro Dynamics as a heuristic model. ► We represent the vacuum as a form of turbulent ether. ► This picture can be tested with forthcoming ether-drift experiments. - Abstract: We re-consider the idea that quantum fluctuations might reflect the existence of an ‘objective randomness’, i.e. a basic property of the vacuum state which is independent of any experimental accuracy of the observations or limited knowledge of initial conditions. Besides being responsible for the observed quantum behavior, this might introduce a weak, residual form of ‘noise’ which is intrinsic to natural phenomena and could be important for the emergence of complexity at higher physical levels. By adopting Stochastic Electro Dynamics as a heuristic model, we are driven to a picture of the vacuum as a form of highly turbulent ether, which is deep-rooted into the basic foundational aspects of both quantum physics and relativity, and to search for experimental tests of this scenario. An analysis of the most precise ether-drift experiments, operating both at room temperature and in the cryogenic regime, shows that, at present, there is some ambiguity in the interpretation of the data. In fact the average amplitude of the signal has precisely the magnitude expected, in a ‘Lorentzian’ form of relativity, from an underlying stochastic ether and, as such, might not be a spurious instrumental effect. This puzzle, however, should be solved in a next future with the use of new cryogenically cooled optical resonators whose stability should improve by about two orders of magnitude. In these new experimental conditions, the persistence of the present amplitude would represent a clean evidence for the type of random vacuum we are envisaging.

  18. A mild and efficient procedure for the synthesis of ethers from various alkyl halides

    Directory of Open Access Journals (Sweden)

    Mosstafa Kazemi

    2013-10-01

    Full Text Available A simple, mild and practical procedure has been developed for the synthesis of symmetrical and unsymmetrical ethers by using DMSO, TBAI in the presence of K2CO3. We extended the utility of Potassium carbonate as an efficient base for the preparation of ethers. A wide range of alkyl aryl and dialkyl ethers are synthezied from treatment of aliphatic alcohols and phenols with various alkyl halides in the prescence of efficient base Potassium carbonate. Secondary alkyl halides were easily converted to corresponding ethers in releatively good yields . This is a mild, simple and practical procedure for the preparation of ethers in high yields and suitable times under mild condition.

  19. Modified nanocrystal cellulose/fluorene-containing sulfonated poly(ether ether ketone ketone) composites for proton exchange membranes

    Science.gov (United States)

    Wei, Yingcong; Shang, Yabei; Ni, Chuangjiang; Zhang, Hanyu; Li, Xiaobai; Liu, Baijun; Men, Yongfeng; Zhang, Mingyao; Hu, Wei

    2017-09-01

    Highly sulfonated poly(ether ether ketone ketone)s (SFPEEKKs) with sulfonation degrees of 2.34 (SFPEEKK5) and 2.48 (SFPEEKK10) were synthesized through the direct sulfonation of a fluorene-containing poly(ether ether ketone ketone) under a relatively mild reaction condition. Using the solution blending method, sulfonated nanocrystal cellulose (sNCC)-enhanced SFPEEKK composites (SFPEEKK/sNCC) were successfully prepared for investigation as proton exchange membranes. Transmission electron microscopy showed that sNCC was uniformly distributed in the composite membranes. The properties of the composite membranes, including thermal stability, mechanical properties, water uptake, swelling ratio, oxidative stability and proton conductivity were thoroughly evaluated. Results indicated that the insertion of sNCC could contribute to water management and improve the mechanical performance of the membranes. Notably, the proton conductivity of SFPEEKK5/sNCC-5 was as high as 0.242 S cm-1 at 80 °C. All data proved the potential of SFPEEKK/sNCC composites for proton exchange membranes in medium-temperature fuel cells.

  20. Enhanced response of microbial fuel cell using sulfonated poly ether ether ketone membrane as a biochemical oxygen demand sensor

    Energy Technology Data Exchange (ETDEWEB)

    Ayyaru, Sivasankaran; Dharmalingam, Sangeetha, E-mail: sangeetha@annauniv.edu

    2014-03-01

    Graphical abstract: - Highlights: • Sulfonated poly ether ether ketone (SPEEK) membrane in SCMFC used to determine the BOD. • The biosensor produces a good linear relationship with the BOD concentration up to 650 ppm. • This sensing range was 62.5% higher than that of Nafion{sup ®}. • SPEEK exhibited one order lesser oxygen permeability than Nafion{sup ®}. • Nafion{sup ®} shows high anodic internal resistance (67 Ω) than the SPEEK (39 Ω). - Abstract: The present study is focused on the development of single chamber microbial fuel cell (SCMFC) using sulfonated poly ether ether ketone (SPEEK) membrane to determine the biochemical oxygen demand (BOD) matter present in artificial wastewater (AW). The biosensor produces a good linear relationship with the BOD concentration up to 650 ppm when using artificial wastewater. This sensing range was 62.5% higher than that of Nafion{sup ®}. The most serious problem in using MFC as a BOD sensor is the oxygen diffusion into the anode compartment, which consumes electrons in the anode compartment, thereby reducing the coulomb yield and reducing the electrical signal from the MFC. SPEEK exhibited one order lesser oxygen permeability than Nafion{sup ®}, resulting in low internal resistance and substrate loss, thus improving the sensing range of BOD. The system was further improved by making a double membrane electrode assembly (MEA) with an increased electrode surface area which provide high surface area for electrically active bacteria.

  1. RATE CONSTANTS FOR THE REACTIONS OF OH RADICALS AND CL ATOMS WITH DI-N-PROPYL ETHER AND DI-N-BUTYL ETHER AND THEIR DEUTERATED ANALOGS. (R825252)

    Science.gov (United States)

    Using relative rate methods, rate constants for the gas-phase reactions of OH radicals and Cl atoms with di-n-propyl ether, di-n-propyl ether-d14, di-n-butyl ether and di-n-butyl ether-d18 have been measured at 296 ? 2 K and atmos...

  2. Biodegradability of fuel-ethers in environment; Biodegradabilite des ethers-carburants dans l'environnement

    Energy Technology Data Exchange (ETDEWEB)

    Fayolle-Guichard, F.

    2005-04-01

    Fuel ethers (methyl tert-butyl ether or MTBE, ethyl tert-butyl ether or ETBE and tert-amyl methyl ether or TAME have been used as gasoline additives since about twenty years in order to meet the requirements for the octane index and to limit the polluting emission in exhaust pipe gas (unburnt hydrocarbons and carbon monoxide). The high water solubility and the poor biodegradability of these compounds make them pollutants frequently encountered in aquifers. The present manuscript summarizes the knowledge concerning the biodegradability of fuel ethers obtained both at IFP and during collaborations with the Pasteur Institute (Paris), the Biotechnology Research Institute (Montreal, Canada) and the Center for Environmental Biotechnology (University of Tennessee, USA). Rhodococcus ruber IFP 2001 and Mycobacterium austroafricanum IFP 2012, two microorganisms isolated at IFP for their ability to grow, respectively, on ETBE and MTBE, were studied in order to determine the intermediates produced during MTBE and ETBE biodegradation and the enzymes required for each biodegradation step, thus allowing us to propose MTBE and ETBE catabolic pathways. A proteomic approach, from the protein induced during the degradation of ETBE or MTBE to the genes encoding these different enzymes, was carried out. The isolation of such genes is required:1) to use them for help in determining the bio-remediation capacities in polluted aquifers (DNA micro-arrays), 2) to monitor the microorganisms isolated for their degradative capacities during bio-remediation processes (fluorescent in situ hybridization or FISH) and 3) to create new tools for the detection and the quantification of ETBE or MTBE in contaminated aquifers (bio-sensor). The manuscript also describes the different ways for the adaptation of microorganisms to the presence of a xenobiotic compound. (author)

  3. Modification of glassy carbon electrode with poly(hydroxynaphthol blue)/multi-walled carbon nanotubes composite and construction a new voltammetric sensor for the simultaneous determination of hydroquinone, catechol, and resorcinol

    Science.gov (United States)

    Daneshinejad, Hassan; Arab Chamjangali, Mansour; Goudarzi, Nasser; Hossain Amin, Amir

    2018-03-01

    A novel voltammetric sensor is developed based on a poly(hydroxynaphthol blue)/multi-walled carbon nanotubes-modified glassy carbon electrode for the simultaneous determination of the dihydroxybenzene isomers hydroquinone (HQ), catechol (CC), and resorcinol (RS). The preparation and basic electrochemical performance of the sensor are investigated in details. The electrochemical behavior of the dihydroxybenzene isomers at the sensor is studied by the cyclic and differential pulse voltammetric techniques. The results obtained show that this new electrochemical sensor exhibits an excellent electro-catalytic activity towards oxidation of the three isomers. The mechanism of this electro-catalytic activity is discussed. Using the optimum parameters, limit of detection obtained 0.24, 0.24, and 0.26 μmol L-1 for HQ, CC, and RS, respectively. The modified electrode is also successfully applied to the simultaneous determination of dihydroxybenzene in water samples.

  4. Synthesis of hydroxylated and methoxylated polybrominated diphenyl ethers

    Institute of Scientific and Technical Information of China (English)

    ZHENG Ke-wen; GAO Li-ping; CAO Jie; YU Hai-wen; ZHANG Zhang

    2009-01-01

    Hydroxylated/methoxylated polybrominated diphenyl ethers (OH/MeO-PBDEs) are not only detected as natural products, but also regarded as metabolites formed from polybrominated diphenyl ethers (PBDEs), which are widely used as flame-retardants in various materials. The aim of the present study was to synthesize authentic OH-PBDEs and MeO-PBDEs, as reference standards for environmental exploration. Twenty OH-PBDEs and their corresponding MeO-PBDEs containing three to six bromine atoms were synthesized via a trial of reactions including coupling, oxidation, bromination, methylation, etc. The products were characterized by GC-MS and 1H-NMR spectroscopy in the work. As results show, all compounds synthesized were up to 99% on purity and be reqarded as authentic standards for detecting the chemical pollutants in the emvironment.

  5. SYNTHESIS OF ALLYL PHENYL ETHER AND CLAISEN REARRANGEMENT

    Directory of Open Access Journals (Sweden)

    Gagik Torosyan

    2011-12-01

    Full Text Available It has been established the possibility for phenol allylation on natural zeolites and them analogs. Here is demonstrated the synthesis of allyl phenol, which has wide industrial applications. The offered method in comparison with the traditional methods has more advantages – higher selectivity, smaller material and power resources consumption. It has been obtained the mixture of allylating phenols (30% in general with allyl phenyl ether (1 with 80% yields. At 600 K is obtained allylphenyl ether, at 700 K beginning the formation of allyl phenols, which is the result of direct C-allylation of the aromatic ring. It has been investigated the possibility of Claisen rearrangement in the same conditions. All of that are established by gas-liquid chromatography and liquid chromatography data.

  6. Increasing the thermopower of crown-ether-bridged anthraquinones

    Science.gov (United States)

    Ismael, Ali K.; Grace, Iain; Lambert, Colin J.

    2015-10-01

    We investigate strategies for increasing the thermopower of crown-ether-bridged anthraquinones. The novel design feature of these molecules is the presence of either (1) crown-ether or (2) diaza-crown-ether bridges attached to the side of the current-carrying anthraquinone wire. The crown-ether side groups selectively bind alkali-metal cations and when combined with TCNE or TTF dopants, provide a large phase-space for optimising thermoelectric properties. We find that the optimum combination of cations and dopants depends on the temperature range of interest. The thermopowers of both 1 and 2 are negative and at room temperature are optimised by binding with TTF alone, achieving thermpowers of -600 μV K-1 and -285 μV K-1 respectively. At much lower temperatures, which are relevant to cascade coolers, we find that for 1, a combination of TTF and Na+ yields a maximum thermopower of -710 μV K-1 at 70 K, whereas a combination of TTF and Li+ yields a maximum thermopower of -600 μV K-1 at 90 K. For 2, we find that TTF doping yields a maximum thermopower of -800 μV K-1 at 90 K, whereas at 50 K, the largest thermopower (of -600 μV K-1) is obtain by a combination TTF and K+ doping. At room temperature, we obtain power factors of 73 μW m-1 K-2 for 1 (in combination with TTF and Na+) and 90 μW m-1 K-2 for 2 (with TTF). These are higher or comparable with reported power factors of other organic materials.We investigate strategies for increasing the thermopower of crown-ether-bridged anthraquinones. The novel design feature of these molecules is the presence of either (1) crown-ether or (2) diaza-crown-ether bridges attached to the side of the current-carrying anthraquinone wire. The crown-ether side groups selectively bind alkali-metal cations and when combined with TCNE or TTF dopants, provide a large phase-space for optimising thermoelectric properties. We find that the optimum combination of cations and dopants depends on the temperature range of interest. The

  7. Numerical investigation on the effect of injection pressure on the internal flow characteristics for diethyl ether, dimethyl ether and diesel fuel injectors using CFD

    Directory of Open Access Journals (Sweden)

    Vijayakumar Thulasi

    2011-01-01

    Full Text Available The spray characteristics of the diesel fuel are greatly affected by the cavitation formed inside the injector due to the high pressure differential across the nozzle. Many researchers across the globe are exploring the potential of using diethyl ether and dimethyl ether as an alternate for diesel fuel to meet the strict emission norms. Due to the variation in the fuel properties the internal flow characteristics in injectors for ether fuels are expected to be different from that of the diesel fuel. In this paper computational technique is used to study and compare the internal flow characteristics of diethyl ether, dimethyl ether and diesel fuel. The two phase flow model considering the fuel as a mixture of liquid and vapor is adopted for the simulation study. The injection pressure is varied from 100 to 400 bar and the flow characteristics of all three fuels are simulated and compared. Results indicate that all three fuels have distinct cavitating patterns owing to different property values. The dimethyl ether is found to be more cavitating than diesel and diethyl ether fuels as expected. The mass of fuel injected are found to be decreasing for the ether fuels when compared with diesel fuel at all injection pressures.

  8. Spino ether and its vortices: leptons and hadrons

    Energy Technology Data Exchange (ETDEWEB)

    Skorski, R [College of Engineering, Univ. of Alabama, Alabama (USA)

    1977-03-01

    According to the theory advanced by the author, space is occupied by a spino ether lattice. Where no spino lattice exists, there are black holes. The spino is a kind of massive neutrino with a rest mass of about 7.39x10/sup -47/g and a diameter of 4.56x10/sup -34/cm. The distance between spinos in the spino lattice is about 2x10/sup -10/cm. Spino ether is ubiquitous in all matter, pervades atoms and their nuclei and penetrates matter with no resistance. In fact, hadrons and leptons are shown to be vortices of the spino ether. About one km/sup 3/ of space contains spino ether having a mass equal to 10/sup 80/ baryons, equivalent to the total mass of our universe. If the distances between spinos equaled their diameters, 4.56x10/sup -34/cm instead of 2x10/sup -10/cm, then the diameter of the mass equivalent to our universe would be about 2cm. This is in agreement with the size of the premordial universe, before its explosion, as calculated earlier by other theories. It is conjectured that explosions of energy and mass in space are more frequent on a smaller scale than those in the universe, for example novas, or even on a still smaller scale usually associated with the birth of different nuclei. The abundance of iron in the solar corona, on the surface of Mars, and in the Martin sky appears to be due to hadron formation from space itself.

  9. Percutaneous Dissolution of Gallstones using Methyl Tert-Butyl Ether

    OpenAIRE

    1990-01-01

    Radiolucent cholesterol gallstones can be dissolved rapidly by methyl terc-buryl ether (MTBE) introduced directly into the gallbladder. Percutaneous transhepatic catheter placement is a well established interventional radiology procedure and is the preferred route for MTBE administration. A small number of patients have been treated using nasobiliary placement of a gallbladder catheter. Rapid stirring automatic pump systems allow dissolution of most cholesterol stones, but s...

  10. Extraction separation of lithium isotopes with crown-ethers

    International Nuclear Information System (INIS)

    Tsivadze, A.Yu.; Demin, S.V.; Levkin, A.V.; Zhilov, V.I.; Nikol'skij, S.F.; Knyazev, D.A.

    1990-01-01

    By the method of extraction chromatography lithium isotope separation coefficients are measured during chemical isotope exchange between lithium aquocomplex and its complex in chloroform with crown-ethers: benzo-15-crown-5, 15crown-5, dicyclohexano-18-crown-6 and dibenzo-18-crown-6. Lithium perchlorate and trichloroacetate are the salts extracted. Values of 6 Li/ 7 Li isotope separation are 1.0032-1.020

  11. Patch test with ether extracts in salicaceae allergy

    Directory of Open Access Journals (Sweden)

    Sawhney M

    2002-01-01

    Full Text Available A total of 23 cases suggestive of airborne contact dermatitis were patch tested with ether extracts of flowers and leaves of populus sp. and salix sp. in a study conducted in Ladakh at an altitude of 3445 meters above sea level. Overall positivity was found in 12 (52.17%, with populus sp. alone in 7 (30. 43%, salix sp. alone in 4 17.39% and to both in one (8.33%.

  12. Solution of a gallstone with methyl-tertiary butyl ether

    Energy Technology Data Exchange (ETDEWEB)

    Brambs, H J; Roeren, T; Holstege, A; Raedecke, J

    1987-08-01

    Methyl-t-butyl ether is a new agent to dissolve gallstones. The substance proves to be very successful and acts very rapidly. A percutaneous transhepatic drainage supplies an adequate access route to dissolve calculi within the bile ducts. We report the case of a patient where before insertion of an internal stent a stone in the common bile duct was dissolved within 3 1/2 hours.

  13. Thermogravimetric analysis of the polymer acrylate-vinyl ether mixture cured by radiation

    International Nuclear Information System (INIS)

    Danu, Sugiarto

    1998-01-01

    An experiment on thermal stability of the polymer acrylate-vinyl ether mixture cured by radiation have been done using thermogravimetric analysis. Three kinds of acrylic oligomers i.e., epoxy acrylate, urethane acrylate, and polypropylene glycol diacrylate, and vinyl ether monomers i.e., triethylene glycol divinyl ether (DVE-3), 1,4-cyclohexane dimethanol divinyl ether (CHVE), and butanediol monovinyl ether (HBVE) were used in the experiment. Reaction was taken via radical and cationic polymerisation. In case of cationic polymerisation, diphenyliodonium hexafluorophosphate fotoinisiator was used in the formulation. Thermogravimetric analysis was conducted in a nitrogen atmosphere at a flow rate of 40 ml/minute with a constant heating rate 10 o C and evaluation range were done from 25 to 500 o C. The results of thermogravimetric analysis showed that acrylate and DVE-3 mixture produced the polymer films with higher thermal stability than the mixture of acrylate with CHVE or HBVE. The composition of acrylate-vinyl ether mixture and degree of unsaturation of vinyl ether monomers influenced the thermal stability of polymer. The mixture of epoxy acrylate-vinyl ether and polypropylene glycol diacrylate-vinyl ether have 1 initial decomposition temperature whereas the urethane acrylate-vinyl ether mixture has 2 initial decomposition temperatures. (authors)

  14. Biomedical potentials of crown ethers: prospective antitumor agents.

    Science.gov (United States)

    Kralj, Marijeta; Tusek-Bozić, Ljerka; Frkanec, Leo

    2008-10-01

    Crown ethers are of enormous interest and importance in chemistry, biochemistry, materials science, catalysis, separation, transport and encapsulated processes, as well as in the design and synthesis of various synthetic systems with specific properties, diverse capabilities, and programmable functions. Classical crown ethers are macrocyclic polyethers that contain 3-20 oxygen atoms separated from each other by two or more carbon atoms. They are exceptionally versatile in selectively binding a range of metal ions and a variety of organic neutral and ionic species. Crown ethers are currently being studied and used in a variety of applications beyond their traditional place in chemistry. This review presents additional applications and the ever-increasing biomedical potentials of these intriguing compounds, with particular emphasis on the prospects of their relevance as anticancer agents. We believe that further research in this direction should be encouraged, as crown compounds could either induce toxicities that are different from those of conventional antitumor drugs, or complement drugs in current use, thereby providing a valuable adjunct to therapy.

  15. Hydrolysis of strained bridgehead bicyclic vinyl ethers and sulfides

    International Nuclear Information System (INIS)

    Chwang, W.K.; Kresge, A.J.; Wiseman, J.R.

    1979-01-01

    Rates of hydrolysis of the bridgehead bicyclic vinyl ether 9-oxabicyclo[3.3.1]non-1-ene(6) and its vinyl sulfide counterpart 9-thiabicyclo[3.3.1]non-1-ene(7), catalyzed by the hydronium ion, were measured in H 2 O and in D 2 O solution. These data give isotope effects, k/sub H//k/sub D/ = 2.4 and 1.9 respectively, which show that these reactions occur by the normal, rate-determining carbon protonation, mechanism. The vinyl ether 6 is less reactive than its olefin analogue, bicyclo[3.3.1]non-1-ene (relative rate 1:1/1400), as may have been expected for a constrained bicyclic system such as this, where stabilization of the bridgehead carbocation intermediate by conjugation with oxygen is severely impaired. The vinyl sulfide 7, however, is even less reactive than the vinyl ether (relative rates 1:1/140); this is a remarkable result in view of the fact that conjugation between the sulfur atom and the cationic center is presumably also strongly inhibited. 1 figure, 3 tables

  16. Isotopic exchange of cyclic ethers with deuterium over metal catalysts

    International Nuclear Information System (INIS)

    Duchet, J.C.; Cornet, D.

    1976-01-01

    The exchange reaction between deuterium and cyclic ethers (oxolane and α-methyl derivatives) has been investigated using rhodium and palladium catalysts. The first hydrogen undergoing exchange has been found to be located on a β-carbon. This fact, and the poisoning of the exchange of cyclopentane in the presence of ether, suggest that the O atom participates in the exchange mechanism of ethers. It appears, however, that the oxygen--metal bonding occurs only during this simple exchange process; simultaneous adsorption of oxygen and a vicinal carbon causes hydrogenolysis of the O--C bond. In each case multiple exchange is important. In the oxolane molecule two sets of exchangeable hydrogens are distinguished according to their reactivities, as could be expected by analogy with cycloalkanes. However, this distinction is not so clear in the exchange patterns of substituted oxolanes, since intermediate maxima are observed in these cases. It is suggested that the conformational properties of the substituted rings cause a constraint in the formation of 3,4-diadsorbed oxolanes. Thus, multiple exchange, based on α,β-process, and epimerization via the ''roll-over'' mechanism occur preferentially in certain parts of the molecules

  17. Diethyl Ether Production Process with Various Catalyst Type

    Directory of Open Access Journals (Sweden)

    Widayat

    2013-01-01

    Full Text Available Several H-zeolite and HZSM-5 catalysts was preparated and their characters have also been investigated. H-zeolit Catalyst was preparated from Natural Zeolite that obtained from Malang District and Gunung Kidul District. Diethyl ether was produced by Ethanol with concentration of 95%. This research use fixed bed reactor that 1 gram of catalyst as bed catalyst, atmospheric pressure and temperature 140oC as the operating condition. Ethanol vapor from vaporization tank was driven by 200 ml/min Nitrogen stream. The responds in this research is liquid product concentration; diethyl ether, ethanol, methanol and water concentration. The results showed that the largest ethanol conversion was produced by the use of 56.44% HZSM-5 and the largest yield of diethyl ether diethyl was produced by the use of alumina and H-zeolite catalyst. The larger ratio between natural zeolite with HCl solvent will produce the larger surface area of catalyst and ethanol conversion. The largest ethanol conversion was produced at reactan ratio 1:20.

  18. Determination of polybrominated diphenyl ethers in environmental standard reference materials

    Energy Technology Data Exchange (ETDEWEB)

    Stapleton, Heather M.; Schantz, Michele M.; Wise, Stephen A. [National Institute of Standards and Technology, Analytical Chemistry Division, Gaithersburg, MD (United States); Keller, Jennifer M.; Kucklick, John R. [National Institute of Standards and Technology, Analytical Chemistry Division, Hollings Marine Laboratory, Charleston, SC (United States); Leigh, Stefan D. [National Institute of Standards and Technology, Statistical Engineering Division, Gaithersburg, MD (United States)

    2007-04-15

    Standard reference materials (SRMs) are valuable tools in developing and validating analytical methods to improve quality assurance standards. The National Institute of Standards and Technology (NIST) has a long history of providing environmental SRMs with certified concentrations of organic and inorganic contaminants. Here we report on new certified and reference concentrations for 27 polybrominated diphenyl ether (PBDE) congeners in seven different SRMs: cod-liver oil, whale blubber, fish tissue (two materials), mussel tissue and sediment (two materials). PBDEs were measured in these SRMs, with the lowest concentrations measured in mussel tissue (SRM 1974b) and the highest in sediment collected from the New York/New Jersey Waterway (SRM 1944). Comparing the relative PBDE congener concentrations within the samples, we found the biota SRMs contained primarily tetrabrominated and pentabrominated diphenyl ethers, whereas the sediment SRMs contained primarily decabromodiphenyl ether (BDE 209). The cod-liver oil (SRM 1588b) and whale blubber (SRM 1945) materials were also found to contain measurable concentrations of two methoxylated PBDEs (MeO-BDEs). Certified and reference concentrations are reported for 12 PBDE congeners measured in the biota SRMs and reference values are available for two MeO-BDEs. Results from a sediment interlaboratory comparison PBDE exercise are available for the two sediment SRMs (1941b and 1944). (orig.)

  19. Preparation and characterization of poly (methyl methacrylate) and sulfonated poly (ether ether ketone) blend ultrafiltration membranes for protein separation applications

    International Nuclear Information System (INIS)

    Arthanareeswaran, G.; Thanikaivelan, P.; Raajenthiren, M.

    2009-01-01

    Poly (methyl methacrylate) (PMMA) and poly (methyl methacrylate)/sulfonated poly (ether ether ketone) (SPEEK) blend membranes were prepared by phase inversion technique in various composition using N,N'-dimethylformamide as solvent. The prepared membranes were characterized in terms of pure water flux, water content, porosity and thermal stability. The addition of SPEEK to the casting solution resulted in membranes with high pure water flux, water content, porosity and slightly low thermal stability. The cross sectional views of the blend membranes under electron microscope confirm the porosity and water flux results. The effect of the addition of SPEEK into the PMMA matrix on the extent of bovine serum albumin (BSA) separation was studied. It was found that the permeate flux increased significantly while the rejection of BSA from aqueous solution reduced moderately during ultrafiltration (UF) process. The effect was attributed to the increase in porosity and charge of the membrane due to the addition of SPEEK into the PMMA blend solution

  20. Poly (ether ether ketone) membranes for fuel cells; Membranas de poli (eter eter cetona) sulfonado para celulas a combustivel

    Energy Technology Data Exchange (ETDEWEB)

    Marrero, Jacqueline C.; Gomes, Ailton de S.; Filho, Jose C.D., E-mail: jacquecosta@gmail.com [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Hui, Wang S. [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil); Oliveira, Vivianna S. de [Escola Tecnica Rezende-Rammel, Rio de Janeiro, RJ (Brazil)

    2015-07-01

    Polymeric membranes were developed using a SPEEK polymer matrix (sulphonated poly (ether ether ketone)), containing hygroscopic particles of zirconia (Zr) (incorporated by sol-gel method), for use as electrolyte membranes in fuel cells. SPEEK with different sulfonation degrees were used: 63 and 86%. The thermal analysis (TGA and DSC) was carried out to characterize the membranes and electrochemical impedance spectroscopy (EIS) was carried out to evaluating the proton conductivity of the membranes. Additional analysis were underway in order to characterize these membranes, which include: X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) in order to evaluate the influence of zirconia and sulfonation degree on the properties of the membranes. (author)

  1. Preparation of poly(ether ether ketone)-based polymer electrolytes for fuel cell membranes using grafting technique

    International Nuclear Information System (INIS)

    Hasegawa, Shin; Suzuki, Yasuyuki; Maekawa, Yasunari

    2008-01-01

    Poly(ether ether ketone) (PEEK)-based polymer electrolyte membranes (PEMs) was successfully prepared by radiation grafting of a styrene monomer into PEEK films and the consequent selective sulfonation of the grafting chains in the film state. Using milder sulfonation, the sulfonation reactions proceeded at the grafted chains in preference to the phenylene rings of PEEK main chains; as a result, the grafted films could successfully transform to a PEM with conductivity of more than 0.1 S/cm. The ion exchange capacity (IEC) and conductivity of the grafted PEEK electrolyte membranes were controlled to the ranges of 1.2-2.9 mmol/g and 0.03-0.18 S/cm by changing the grafting degree. It should be noted that this is the first example of directly transforming super-engineering plastic films into a PEM using radiation grafting

  2. Sulfonated Poly(Ether Ether Ketone)/Functionalized Carbon Nanotube Composite Membrane for Vanadium Redox Flow Battery Applications

    International Nuclear Information System (INIS)

    Jia, Chuankun; Cheng, Yuanhang; Ling, Xiao; Wei, Guanjie; Liu, Jianguo; Yan, Chuanwei

    2015-01-01

    A novel sulfonated poly(ether ether ketone) (SPEEK) membrane embedded with the short-carboxylic multi-walled carbon nanotube (we name it as SPEEK/SCCT membrane) for vanadium redox flow battery (VRB) has been prepared with low capacity loss, low cost and high energy efficiency. The mechanical strength, vanadium ions permeability and performance of the membrane in the VRB single cell were characterized. Results showed that the SPEEK/SCCT membrane possessed low permeability of vanadium ions, accompanied by higher mechanical strength than the Nafion 212 membrane. The VRB single cell with SPEEK/SCCT membrane showed 7% higher coulombic efficiency (CE), 6% higher energy efficiency (EE) but lower capacity loss in comparison with the one with Nafion 212. The good cell performance, low capacity loss and high vanadium ions barrier properties of the blend membrane is of significant interest for VRB applications

  3. Poly(mono/diethylene glycol n-tetradecyl ether vinyl ethers with Various Molecular Weights as Phase Change Materials

    Directory of Open Access Journals (Sweden)

    Dongfang Pei

    2018-02-01

    Full Text Available At present, research on the relationship of comb-like polymer phase change material structures and their heat storage performance is scarce. Therefore, this relationship from both micro and macro perspectives will be studied in this paper. In order to achieve a high phase change enthalpy, ethylene glycol segments were introduced between the vinyl and the alkyl side chains. A series of poly(mono/diethylene glycol n-tetradecyl ether vinyl ethers (PC14EnVEs (n = 1, 2 with various molecular weights were polymerized by living cationic polymerization. The results of PC14E1VE and PC14E2VE showed that the minimum number of carbon atoms required for side-chain crystallization were 7.7 and 7.2, which were lower than that reported in the literature. The phase change enthalpy 89 J/g (for poly(mono ethylene glycol n-tetradecyl ether vinyl ethers and 86 J/g (for poly(hexadecyl acrylate were approximately equal. With the increase of molecular weight, the melting temperature, the melting enthalpy, and the initial thermal decomposition temperature of PC14E1VE changed from 27.0 to 28.0 °C, from 95 to 89 J/g, and from 264 to 287 °C, respectively. When the number average molar mass of PC14EnVEs exceeded 20,000, the enthalpy values remained basically unchanged. The introduction of the ethylene glycol chain was conducive to the crystallization of alkyl side chains.

  4. Densely quaternized poly(arylene ether)s with distinct phase separation for highly anion-conductive membranes

    Science.gov (United States)

    Hu, Yuanfang; Wang, Bingxi; Li, Xiao; Chen, Dongyang; Zhang, Weiying

    2018-05-01

    To develop high performance anion exchange membranes (AEMs), a novel bisphenol monomer bearing eight benzylmethyl groups at the outer edge of the molecule was synthesized, which after condensation polymerization with various amounts of 4,4‧-dihydroxydiphenylsulfone and 4,4‧-difluorobenzophenone yielded novel poly(arylene ether)s with densely located benzylmethyl groups. These benzylmethyl groups were then converted to quaternary ammonium groups by radical-initiated bromination and quaternization in tandem, leading to the emergence of densely quaternized poly(arylene ether sulfone)s (QA-PAEs) with controlled ion exchange capacities (IECs) ranging from 1.61 to 2.32 mmol g-1. Both small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM) studies revealed distinct phase separation in the QA-PAEs. The QA-PAE-40 with an IEC of 2.32 mmol g-1 exhibited a Br- conductivity of 9.2 mS cm-1 and a SO42- conductivity of 14.0 mS cm-1 at room temperature, much higher than those of a control membrane with a similar IEC but without obvious phase separation. Therefore, phase separation of AEMs was validated to be advantageous for the efficient conducting of anions. The experimental results also showed that the QA-PAEs were promising AEM materials, especially for non-alkaline applications.

  5. The breakdown of vinyl ethers as a two-center synchronous reaction

    Science.gov (United States)

    Pokidova, T. S.; Shestakov, A. F.

    2009-11-01

    The experimental data on the molecular decomposition of vinyl ethers of various structures to alkanes and the corresponding aldehydes or ketones in the gas phase were analyzed using the method of intersecting parabolas. The enthalpies and kinetic parameters of decomposition were calculated for 17 reactions. The breakdown of ethers is a two-center concerted reaction characterized by a very high classical potential barrier to the thermally neutral reaction (180-190 kJ/mol). The kinetic parameters (activation energies and rate constants) of back reactions of the formation of vinyl ethers in the addition of aldehydes or ketones to alkanes were calculated using the method of intersecting parabolas. The factors that influenced the activation energy of the decomposition and formation of ethers were discussed. Quantum-chemical calculations of several vinyl ether decomposition reactions were performed. Ether formation reactions were compared with the formation of unsaturated alcohols as competitive reactions, which can occur in the interaction of carbonyl compounds with alkenes.

  6. Gold-catalyzed alkylation of silyl enol ethers with ortho-alkynylbenzoic acid esters

    Directory of Open Access Journals (Sweden)

    Yoshinori Yamamoto

    2011-05-01

    Full Text Available Unprecedented alkylation of silyl enol ethers has been developed by the use of ortho-alkynylbenzoic acid alkyl esters as alkylating agents in the presence of a gold catalyst. The reaction probably proceeds through the gold-induced in situ construction of leaving groups and subsequent nucleophilic attack on the silyl enol ethers. The generated leaving compound abstracts a proton to regenerate the silyl enol ether structure.

  7. Thermodynamics of Hydrogen Production from Dimethyl Ether Steam Reforming and Hydrolysis

    Energy Technology Data Exchange (ETDEWEB)

    T.A. Semelsberger

    2004-10-01

    The thermodynamic analyses of producing a hydrogen-rich fuel-cell feed from the process of dimethyl ether (DME) steam reforming were investigated as a function of steam-to-carbon ratio (0-4), temperature (100 C-600 C), pressure (1-5 atm), and product species: acetylene, ethanol, methanol, ethylene, methyl-ethyl ether, formaldehyde, formic acid, acetone, n-propanol, ethane and isopropyl alcohol. Results of the thermodynamic processing of dimethyl ether with steam indicate the complete conversion of dimethyl ether to hydrogen, carbon monoxide and carbon dioxide for temperatures greater than 200 C and steam-to-carbon ratios greater than 1.25 at atmospheric pressure (P = 1 atm). Increasing the operating pressure was observed to shift the equilibrium toward the reactants; increasing the pressure from 1 atm to 5 atm decreased the conversion of dimethyl ether from 99.5% to 76.2%. The order of thermodynamically stable products in decreasing mole fraction was methane, ethane, isopropyl alcohol, acetone, n-propanol, ethylene, ethanol, methyl-ethyl ether and methanol--formaldehyde, formic acid, and acetylene were not observed. The optimal processing conditions for dimethyl ether steam reforming occurred at a steam-to-carbon ratio of 1.5, a pressure of 1 atm, and a temperature of 200 C. Modeling the thermodynamics of dimethyl ether hydrolysis (with methanol as the only product considered), the equilibrium conversion of dimethyl ether is limited. The equilibrium conversion was observed to increase with temperature and steam-to-carbon ratio, resulting in a maximum dimethyl ether conversion of approximately 68% at a steam-to-carbon ratio of 4.5 and a processing temperature of 600 C. Thermodynamically, dimethyl ether processed with steam can produce hydrogen-rich fuel-cell feeds--with hydrogen concentrations exceeding 70%. This substantiates dimethyl ether as a viable source of hydrogen for PEM fuel cells.

  8. Interpolymer complexses of vinyl ether copolymer with polyacrylic and polymethacrylic acids

    Directory of Open Access Journals (Sweden)

    E. Shaikhutdinov

    2012-03-01

    Full Text Available The interactions between macromolecules of copolymers based on vinyl ethers (vinyl ether of monoethanolamine and vinyl buthyl ether and 2-acryloilamido-2-methylpropanesulphonic acid with polyacrylic and polymethacrylic acid and, as well as study the effect of interpolymer interactions in the adsorption of polymers at the aqueous solution-air interface were investigated. The observed synergistic increase in surface activity of macromolecules into polyelectrolyte mixtures explained by the formation of interpolymer complexes polyacid - copolymer.

  9. Synthesis of Poly(vinyl ether) Thermoplastic Elastomers Having Functional Soft Segments

    OpenAIRE

    今枝, 嗣人; 漆崎, 美智遠; 阪口, 壽一; 橋本, 保; Tsuguto, IMAEDA; Michio, URUSHISAKI; Toshikazu, SAKAGUCHI; Tamotsu, HASHIMOTO

    2013-01-01

    The ABA-type triblock copolymers consisting of poly(2-adarnantyl vinyl ether) [poly(2-AdVE) as outer hard segments and poly(6-acetoxyhexyl vinyl ether) [poly(AcHVE)] poly(6-hydroxyhexyl vinyl ether) [poly(H HVE)], or poly(2-(2-methoxyethoxy)ethyl vinyl ether [poly(MOEOVE)] as inner soft segments were synthesized by sequential living cationic polymerization. Despite the presence of polar functional groups such as ester, hydroxy, and oxyethylene units in their soft segments, the two polymer seg...

  10. AIRBORNE POLYBROMINATED DIPHENYL ETHERS IN A COMPUTER CLASSROOM OF COLLEGE IN TAIWAN

    Directory of Open Access Journals (Sweden)

    F. H. Chang ، C. R. Yang ، C. Y. Tsai ، W. C. Lin

    2009-04-01

    Full Text Available This study characterized the airborne exposure of students to thirty polybrominated diphenyl ether congeners inside and outside a computer classroom in a southern Taiwan college. Arithmetic mean values of total indoor and outdoor polybrominated diphenyl ether concentrations were 125.0 pg/m3 (89.8 to 203.9 pg/m3 and 110.3 pg/m3 (83.5 to 157.0 pg/m3, respectively. Total indoor polybrominated diphenyl ether concentrations were one order of magnitude lower than those detected in homes in Birmingham, United Kingdom and in Ottawa, Canada but were several times higher than those measured in the ambient air in Ottawa, Canada and from the Bohai Sea to the Arctic. The five highest indoor concentrations of polybrominated diphenyl ether congeners were decabromodiphenyl ether (23.0 pg/m3, 4,4’-dibromodiphenyl ether (15.9 pg/m3, 2,2’,3,4,4’,5,5’,6-octabromodiphenyl ether (10.6 pg/m3, 2,4-dibromodiphenyl ether (10.3 pg/m3 and 2,2’,3,4,4’,5’,6-heptabromodiphenyl ether (10.0 pg/m3. Although indoor and outdoor total polybrominated diphenyl ether concentrations did not significantly differ, the indoor concentrations of 2,4-dibromodiphenyl ether, 2,2’,4-tribromodiphenyl ether, 2,4,4’-tribromodiphenyl ether, 2,2’,4,5’-tetrabromodiphenyl ether and 2,3’,4’,6-tetrabromodiphenyl ether were significantly higher than their outdoor concentrations. This study suggests the following measures: 1 to increase the air exchange rate and open classroom doors and windows for several minutes before classes to reduce indoor PBDE concentrations; 2 to reduce polybrominated diphenyl ether emissions from new devices, it’s better to use computer-related products that meet the Restriction of Hazardous Substances Directive adopted by the European Union.

  11. [Early contributions from Erlangen to the theory and practice of ether and chloroform anesthesia. 1. Heyfelder's clinical trial with ether and chloroform].

    Science.gov (United States)

    Hintzenstern, U v; Schwarz, W

    1996-02-01

    The era of modern anaesthesia in Germany began on January 24th, 1847. This day, professor in ordinary Johann Ferdinand Heyfelder anaesthetized a patient with sulphuric ether in the clinic of surgery and ophthalmology of the University of Erlangen. By March 17th, 1847, Heyfelder had performed 121 surgical procedures under ether. The operations in majority were teeth-extractions, and a few more complex operations such as the treatment of a harelip or of lip cancer or the resection of the shoulder joint. Heyfelder described in detail 108 of these inhalations in a little book entitled The experiments with sulphuric ether. This monograph published in March, 1847, represents one of the first complete dissertations on sulphuric ether in the German literature. In a special chapter he analyzed the development of various physiological and psychological parameters during etherization. Heyfelder also examined blood and urine of some etherized patients and reported that he did not find any important or specific alterations. In 1847, Heyfelder was probably the first to apply salt-ether in man. After 4 administrations he concluded that salt ether acted more quickly but shorter than sulphuric ether. Advantageous were its application without problems and ease of induction. Disadvantageous were its high volatility, its price and the difficulty of getting it in a pure form. From December, 1847, on Heyfelder started to use chloroform. He was now able to perform more major operations, for example, the total resection of the hip-joint. In his book The experiments with sulphuric ether, salt ether, and chloroform he describes a great number of anaesthetic administrations using these 3 agents. In his summary Heyfelder concluded, that chloroform was undoubtly superior to sulphuric ether mainly because it was a quicker acting and longer lasting agent and leads to deeper narcosis. Moreover its application was much easier for it needed no special apparatus. However, because of its great

  12. Green mechanochemical oxidative decomposition of powdery decabromodiphenyl ether with persulfate

    International Nuclear Information System (INIS)

    Huang, Aizhen; Zhang, Zhimin; Wang, Nan; Zhu, Lihua; Zou, Jing

    2016-01-01

    Highlights: • MC process greatly enhanced the decomposition of PS into reactive sulfate radicals. • The mechanochemical (MC) activation of persulfate was applied to degrade BDE209. • This method could achieve a rapid and complete debromination and mineralization of BDE209. • No toxic low brominated polybrominated diphenyl ethers were produced and accumulated. • Sulfate radicals were the main oxidizing species for the decomposition of BDE209. - Abstract: A method was developed for efficiently degrading powdery decabromodiphenyl ether (BDE209) by using mechanochemical (MC) activation of persulfate (PS). Characteristic Raman spectra of BDE209 corresponding to C−Br and C−O bonds were decreased in intensity and finally disappeared as the MC reaction proceeded. The BDE209 removal was influenced by the molar ratio of PS to BDE209, the mass ratio of milling ball to reaction mixtures, the ball size, and the ball rotation speed. Under optimal conditions, the new method could achieve a complete degradation, debromination and mineralization of BDE209 within 3 h of milling. However, the degradation removal (or debromination efficiency) was decreased to only 51.7% (15.6%) and 67.8% (31.5%) for the use of CaO and peroxymonosulfate, respectively. The analyses of products demonstrated that once the degradation was initiated, BDE209 molecules were deeply debrominated and fully mineralized in the MC-PS system. The strong oxidizing ability of this system was due to the reactive sulfate radicals generated from the MC-enhanced activation of PS, which was confirmed with electron spin resonance spectroscopy. Because no toxic low brominated polybrominated diphenyl ethers were accumulated as byproducts, the proposed MC oxidative degradation method will have promising applications in the treatment of solid BDE209 at high concentrations.

  13. Microbial degradation of 4-monobrominated diphenyl ether with anaerobic sludge

    International Nuclear Information System (INIS)

    Shih, Yang-hsin; Chou, Hsi-Ling; Peng, Yu-Huei

    2012-01-01

    Highlights: ► BDE-3 was degraded with two anaerobes in different rates. ► Glucose addition augment the debromination efficiencies. ► Hydrogen gas was detected and relative microbes were identified. ► Extra-carbon source enhanced degradation partial due to H 2 -generation bacteria. - Abstract: Polybrominated diphenyl ethers (PBDEs) are widely used flame retardant additives for many plastic and electronic products. Owing to their ubiquitous distribution in the environment, multiple toxicity to humans, and increasing accumulation in the environment, the fate of PBDEs is of serious concern for public safety. In this study, the degradation of 4-monobrominated diphenyl ether (BDE-3) in anaerobic sludge and the effect of carbon source addition were investigated. BDE-3 can be degraded by two different anaerobic sludge samples. The by-products, diphenyl ether (DE) and bromide ions, were monitored, indicating the reaction of debromination within these anaerobic samples. Co-metabolism with glucose facilitated BDE-3 biodegradation in terms of kinetics and efficiency in the Jhongsing sludge. Through the pattern of amplified 16S rRNA gene fragments in denatured gradient gel electrophoresis (DGGE), the composition of the microbial community was analyzed. Most of the predominant microbes were novel species. The fragments enriched in BDE-3-degrading anaerobic sludge samples are presumably Clostridium sp. This enrichment coincides with the H 2 gas generation and the facilitation of debromination during the degradation process. Findings of this study provide better understanding of the biodegradation of brominated DEs and can facilitate the prediction of the fate of PBDEs in the environment.

  14. Dimethyl ether production from methanol and/or syngas

    Science.gov (United States)

    Dagle, Robert A; Wang, Yong; Baker, Eddie G; Hu, Jianli

    2015-02-17

    Disclosed are methods for producing dimethyl ether (DME) from methanol and for producing DME directly from syngas, such as syngas from biomass. Also disclosed are apparatus for DME production. The disclosed processes generally function at higher temperatures with lower contact times and at lower pressures than conventional processes so as to produce higher DME yields than do conventional processes. Certain embodiments of the processes are carried out in reactors providing greater surface to volume ratios than the presently used DME reactors. Certain embodiments of the processes are carried out in systems comprising multiple microchannel reactors.

  15. Polybrominated diphenyl ether flame retardants in Virginia freshwater fishes (USA).

    Science.gov (United States)

    Hale, R C; La Guardia, M J; Harvey, E P; Mainor, T M; Duff, W H; Gaylor, M O

    2001-12-01

    Polybrominated diphenyl ethers (PBDEs) were examined in fish fillets collected from two large Virginia watersheds. Emphasis was on the tetra- to hexabrominated congeners since these exhibit the greatest bioaccumulation and toxicological potentials. These congeners are dominant constituents of Penta-, a commercial PBDE product used to flame retard polyurethane foam. In 1999, North America accounted for98% of global Penta-demand. Concentrations of total tetra- to hexabrominated congeners in fillets ranged from furniture and textile manufacturing, although polyurethane foam production here has been limited.

  16. Performance of long straw tubes using dimethyl ether

    International Nuclear Information System (INIS)

    Benussi, L.; Bertani, M.; Bianco, S.; Fabbri, F.L.; Gianotti, P.; Giardoni, M.; Guaraldo, C.; Lanaro, A.; Lucherini, V.; Mecozzi, A.; Passamonti, L.; Russo, V.; Sarwar, S.

    1995-01-01

    A cylindrical tracking detector with an inner radius of one meter employing straw tubes is being envisaged for the FINUDA experiment aimed at hyper-nuclear physics at DAΦNE, the Frascati φ-factory. A prototype using several 10 mm and 20 mm diameter, two meter long aluminized mylar straws has been assembled and tested with a one GeV/c pion beam. While operating with dimethyl ether, gas gain, space resolution, and device systematics have been studied. A simple method of correction for systematics due to straw eccentricity has been developed and, once applied, a space resolution better than 40 μm can be reached. (orig.)

  17. Radiochemical determination of 210Pb using crown ether

    International Nuclear Information System (INIS)

    Vajda, N.; Bodizs, D.; Vodicska, M.

    1994-01-01

    Gamma spectrometric determination of 210 Pb following chemical separation has been performed very precisely and with high sensitivity, due to the low and constant self-absorption of the chemically pure sample. A simple and quick method for the chemical separation of lead using crown ether has been developed. Its four steps are described in detail. The new method was verified using phosphate ore and gypsum samples that were measured in an interlaboratory comparison and with a standard reference material. This method can also be used for self-absorption correction in direct gamma spectrometry of 210 Pb. (N.T.) 4 refs.; 2 figs.; 2 tabs

  18. Total syntheses of naturally occurring diacetylenic spiroacetal enol ethers.

    Science.gov (United States)

    Miyakoshi, Naoki; Aburano, Daisuke; Mukai, Chisato

    2005-07-22

    A highly stereoselective method for constructing a (2E)-methoxymethylidene-1,6-dioxaspiro[4.5]decane skeleton has been developed on the basis of the palladium(II)-catalyzed ring-closing reaction of the 3,4-dioxygenated-9-hydroxy-1-nonyn-5-one derivatives as a crucial step. The newly developed procedures could be successfully applied to the first total synthesis of five diacetylenic spiroacetal enol ether natural products starting from commercially available (R,R)- or (S,S)-diethyl tartrate.

  19. Effect of p-amino-diphenyl ethers on hepatic microsomal cytochrome P450.

    Science.gov (United States)

    Jiang, Huidi; Xuan, Guida

    2003-09-01

    The present paper aims to investigate whether p-amino-2',4'-dichlorodiphenyl ether and p-amino-4'-methyldiphenyl ether are inhibitors as well as inducers of P450. Mice were given daily intraperitoneal (ip) injections of p-amino-2',4'-dichlorodiphenyl ether (0.25 mmol/kg) or p-amino-4'-methyldiphenyl ether (0.25 mmol/kg) for 4 days and tested at 24 h and 48 h after the last dose injection. The results showed the mice pentobarbital sleeping time was shorter and the P450 content of hepatic microsome increased significantly in the group pretreated with p-amino-4'-methyldiphenyl ether when compared with the control group, while in mice pretreated with p-amino-2',4'-dichlorodiphenyl ether the hepatic microsome P450 content increased but the pentobarbital sleeping time was extended in clear contrast to the control group. The sleeping time of the phenobarbital group (80 mg/kg daily ip injection for 4 days) was shortened at 24 h after the last injection with increased P450 content of hepatic microsome, but it showed no difference at 48 h. The zoxazolamine-paralysis times of mice treated with p-amino-2',4'-dichlorodiphenyl ether were longer than those of the control mice, while the same dose of zoxazolamine did not lead to paralysis in mice pretreated with BNF. p-Amino-2',4'-dichlorodiphenyl ether and p-amino-4'-methyldiphenyl ether inhibited the activity of 7-ethoxyresorufin O-deethylase from rat hepatic microsome induced by BNF in vitro by 70.0% and 50.1% respectively. These results suggest that p-amino-2',4'-dichlorodiphenyl ether and p-amino-4'-methyldiphenyl ether are inhibitors as well as inducers of P450.

  20. Sorption-desorption behavior of polybrominated diphenyl ethers in soils

    International Nuclear Information System (INIS)

    Olshansky, Yaniv; Polubesova, Tamara; Vetter, Walter; Chefetz, Benny

    2011-01-01

    Polybrominated diphenyl ethers (PBDEs) are flame retardants that are commonly found in commercial and household products. These compounds are considered persistent organic pollutants. In this study, we used 4,4'-dibromodiphenyl ether (BDE-15) as a model compound to elucidate the sorption and desorption behavior of PBDEs in soils. The organic carbon-normalized sorption coefficient (K OC ) of BDE-15 was more than three times higher for humin than for bulk soils. However, pronounced desorption hysteresis was obtained mainly for bulk soils. For humin, increasing concentration of sorbed BDE-15 resulted in decreased desorption. Our data illustrate that BDE-15 and probably other PBDEs exhibit high sorption affinity to soils. Moreover, sorption is irreversible and thus PBDEs can potentially accumulate in the topsoil layer. We also suggest that although humin is probably a major sorbent for PBDEs in soils, other humic materials are also responsible for their sequestration. - Highlights: → BDE-15 exhibited pronounced desorption hysteresis. → BDE-15 sowed higher sorption affinity to humin as compared to the bulk soils. → Sequestration of PBDEs depends on soil organic matter constitutes other than humin. - Pronounced desorption hysteresis was observed for BDE-15 in natural soils.

  1. Crystal structure and thermal property of polyethylene glycol octadecyl ether

    International Nuclear Information System (INIS)

    Meng, Jie-yun; Tang, Xiao-fen; Li, Wei; Shi, Hai-feng; Zhang, Xing-xiang

    2013-01-01

    Highlights: ► The crystal structure of C18En for n ≥ 20 is a monoclinic system. ► Polyethylene glycol octadecyl ether crystallizes perfectly. ► The number of repeat units has significant effect on the melting, crystallizing temperature and enthalpy. ► The thermal stable temperature increases rapidly with increasing the number of repeat unit. - Abstract: The crystal structure, phase change property and thermal stable temperature (T d ) of polyethylene glycol octadecyl ether [HO(CH 2 CH 2 O) n C 18 H 37 , C18En] with various numbers of repeat units (n = 2, 10, 20 and 100) as phase change materials (PCMs) were investigated using temperature variable Fourier transformed infrared spectroscopy (FTIR), wide-angle X-ray diffraction (XRD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TG). C18En crystallizes perfectly at 0 °C; and the crystal structure for n ≥ 20 is a monoclinic system. The number of repeat units has great effect on the phase change properties of C18En. The thermal stable temperature increases rapidly with increasing the number of repeat units. They approach to that of PEG-2000 as the number of repeat units is more than 10. T d increases rapidly with increasing the number of repeat units. C18En are a series of promising polymeric PCMs

  2. Entropy Generation Minimization in Dimethyl Ether Synthesis: A Case Study

    Science.gov (United States)

    Kingston, Diego; Razzitte, Adrián César

    2018-04-01

    Entropy generation minimization is a method that helps improve the efficiency of real processes and devices. In this article, we study the entropy production (due to chemical reactions, heat exchange and friction) in a conventional reactor that synthesizes dimethyl ether and minimize it by modifying different operating variables of the reactor, such as composition, temperature and pressure, while aiming at a fixed production of dimethyl ether. Our results indicate that it is possible to reduce the entropy production rate by nearly 70 % and that, by changing only the inlet composition, it is possible to cut it by nearly 40 %, though this comes at the expense of greater dissipation due to heat transfer. We also study the alternative of coupling the reactor with another, where dehydrogenation of methylcyclohexane takes place. In that case, entropy generation can be reduced by 54 %, when pressure, temperature and inlet molar flows are varied. These examples show that entropy generation analysis can be a valuable tool in engineering design and applications aiming at process intensification and efficient operation of plant equipment.

  3. Developmental toxicity of diphenyl ether herbicides in nestling American kestrels.

    Science.gov (United States)

    Hoffman, D J; Spann, J W; LeCaptain, L J; Bunck, C M; Rattner, B A

    1991-11-01

    Beginning the day after hatching, American kestrel (Falco sparverius) nestlings were orally dosed for 10 consecutive days with 5 microliters/g of corn oil (controls) or one of the diphenyl ether herbicides (nitrofen, bifenox, or oxyfluorfen) at concentrations of 10, 50, 250, or 500 mg/kg in corn oil. At 500 mg/kg, nitrofen resulted in complete nestling mortality, bifenox in high (66%) mortality, and oxyfluorfen in no mortality. Nitrofen at 250 mg/kg reduced nestling growth as reflected by decreased body weight, crown-rump length, and bone lengths including humerus, radius-ulna, femur, and tibiotarsus. Bifenox at 250 mg/kg had less effect on growth than nitrofen, but crown-rump, humerus, radius-ulna, and femur were significantly shorter than controls. Liver weight as a percent of body weight increased with 50 and 250 mg/kg nitrofen. Other manifestations of impending hepatotoxicity following nitrofen ingestion included increased hepatic GSH peroxidase activity in all nitrofen-treated groups, and increased plasma enzyme activities for ALT, AST, and LDH-L in the 250-mg/kg group. Bifenox ingestion resulted in increased hepatic GSH peroxidase activity in the 50- and 250-mg/kg groups. Nitrofen exposure also resulted in an increase in total plasma thyroxine (T4) concentration. These findings suggest that altricial nestlings are more sensitive to diphenyl ether herbicides than young or adult birds of precocial species.

  4. Alkali-crown ether complexes at metal surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Thontasen, Nicha; Deng, Zhitao; Rauschenbach, Stephan [Max Planck Institute for Solid State Research, Stuttgart (Germany); Levita, Giacomo [University of Trieste, Trieste (Italy); Malinowski, Nikola [Max Planck Institute for Solid State Research, Stuttgart (Germany); Bulgarian Academy of Sciences, Sofia (Bulgaria); Kern, Klaus [Max Planck Institute for Solid State Research, Stuttgart (Germany); EPFL, Lausanne (Switzerland)

    2010-07-01

    Crown ethers are polycyclic ethers which, in solution, selectively bind cations depending on the size of the ring cavity. The study of a single host-guest complex is highly desirable in order to reveal the characteristics of these specific interactions at the atomic scale. Such detailed investigation is possible at the surface where high resolution imaging tools like scanning tunneling microscopy (STM) can be applied. Here, electrospray ion beam deposition (ES-IBD) is employed for the deposition of Dibenzo-24-crown-8 (DB24C8)-H{sup +}, -Na{sup +} and -Cs{sup +} complexes on a solid surface in ultrahigh vacuum (UHV). Where other deposition techniques have not been successful, this deposition technique combines the advantages of solution based preparation of the complex ions with a highly clean and controlled deposition in UHV. Single molecular structures and the cation-binding of DB24C8 at the surface are studied in situ by STM and MALDI-MS (matrix assisted laser desorption ionization mass spectrometry). The internal structure of the complex, i.e. ring and cavity, is observable only when alkali cations are incorporated. The BD24C8-H{sup +} complex in contrast appears as a compact feature. This result is in good agreement with theoretical models based on density functional theory calculations.

  5. Mechanical properties and chemical stability of pivalolactone-based poly(ether ester)s

    NARCIS (Netherlands)

    Tijsma, E.J.; Tijsma, E.J.; van der Does, L.; Bantjes, A.; Bantjes, A.; Vulic, I.

    1994-01-01

    The processing, mechanical and chemical properties of poly(ether ester)s, prepared from pivalolactone (PVL), 1,4-butanediol (4G) and dimethyl terephthalate (DMT), were studied. The poly(ether ester)s could easily be processed by injection moulding, owing to their favourable rheological and thermal

  6. A highly sensitive and selective dimethyl ether sensor based on cataluminescence.

    Science.gov (United States)

    Zhang, Runkun; Cao, Xiaoan; Liu, Yonghui; Peng, Yan

    2010-07-15

    A sensor for detecting dimethyl ether was designed based on the cataluminescence phenomenon when dimethyl ether vapors were passing through the surface of the ceramic heater. The proposed sensor showed high sensitivity and selectivity to dimethyl ether at an optimal temperature of 279 degrees C. Quantitative analysis were performed at a wavelength of 425 nm, the flow rate of carrier air is around 300 mL/min. The linear range of the cataluminescence intensity versus concentration of dimethyl ether is 100-6.0x10(3) ppm with a detection limit of 80 ppm. The sensor response time is 2.5 s. Under the optimized conditions, none or only very low levels of interference were observed while the foreign substances such as benzene, formaldehyde, ammonia, methanol, ethanol, acetaldehyde, acetic acid, acrolein, isopropyl ether, ethyl acetate, glycol ether and 2-methoxyethanol were passing through the sensor. Since the sensor does not need to prepare and fix up the granular catalyst, the simple technology reduces cost, improves stability and extends life span. The method can be applied to facilitate detection of dimethyl ether in the air. The possible mechanism of cataluminescence from the oxidation of dimethyl ether on the surface of ceramic heater was discussed based on the reaction products. Copyright 2010 Elsevier B.V. All rights reserved.

  7. Direct dimethyl ether fueling of a high temperature polymer fuel cell

    DEFF Research Database (Denmark)

    Jensen, Jens Oluf; Vassiliev, Anton; Olsen, M.I.

    2012-01-01

    Direct dimethyl ether (DME) fuel cells suffer from poor DME–water miscibility and so far peak powers of only 20–40 mW cm−2 have been reported. Based on available literature on solubility of dimethyl ether (DME) in water at ambient pressure it was estimated that the maximum concentration of DME at...

  8. Oxime Ethers of (E)-11-Isonitrosostrychnine as Highly Potent Glycine Receptor Antagonists

    DEFF Research Database (Denmark)

    Mohsen, Amal M Y; Mandour, Yasmine M; Sarukhanyan, Edita

    2016-01-01

    of the crystal structure of the α3 glycine receptor indicated the same orientation of the strychnine core for all analogues. For the most potent oxime ethers, the ether substituent was accommodated in a lipophilic receptor binding pocket. The findings identify the oxime hydroxy group as a suitable attachment...

  9. Synthesis of Novel Bibrachial Lariat Ethers (BiBLEs) Containing [1,2 ...

    African Journals Online (AJOL)

    NICO

    A practical and regioselective method for the synthesis of cis-diastereomers of bibrachial lariat ethers (BiBLEs) bearing ester and amide groups is reported. The novel bibrachial lariat ethers (BiBLEs) 3a–d with neutral side chains were prepared by reaction of the corresponding aza-crown macrocycles 1a–b with ethyl ...

  10. Aspects of reaction of N-oxide radical with ethers in 13C NMR spectrum

    International Nuclear Information System (INIS)

    Kolodziejski, W.

    1980-01-01

    The stable radical N-oxide 2,2,6,6-tetramethylpiperidine was dissolved in ethers. The 13 C NMR spectra were recorded in the temperature 313K at the frequency 22,625 MHz on the spectrometers with Fourier transformation. The dissolution of the radical in ether caused the contact shifts in NMR spectra. The shifts were measured. (A.S.)

  11. IRON(III) NITRATE-CATALYZED FACILE SYNTHESIS OF DIPHENYLMETHYL (DPM) ETHERS FROM ALCOHOLS

    Science.gov (United States)

    Diphenyl methyl (DPM) ethers constitute important structural portion of some pharmaceutical entities and also as protective group for hydroxyl groups in synthetic chemistry. DPM ethers are normally prepared using concentrated acids or base as catalysts, which may result in the fo...

  12. 40 CFR 721.7000 - Polymer of disodium maleate, allyl ether, and ethylene oxide.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polymer of disodium maleate, allyl... New Uses for Specific Chemical Substances § 721.7000 Polymer of disodium maleate, allyl ether, and... substance identified generically as a polymer of disodium maleate, allyl ether, and ethylene oxide (P-91...

  13. Ether-Directed ortho-C–H Olefination with a PdII/MPAA Catalyst**

    Science.gov (United States)

    Li, Gang; Leow, Dasheng; Wan, Li; Yu, Jin-Quan

    2013-01-01

    Weak coordination is powerful! A PdII-catalyzed olefination of ortho-C–H bonds of arenes directed by weakly coordinating ethers is developed using mono-protected amino acid (MPAA) ligands. This finding provides a method for chemically modifying ethers, which are abundant in natural products and drug molecules. PMID:23239120

  14. Positron Lifetime Study of the Transition from Glassy to Normal Liquid State for Two Phenyl Ethers

    DEFF Research Database (Denmark)

    Pethrick, R. A.; Jacobsen, F. M.; Mogensen, O. E.

    1980-01-01

    Positron lifetime measurements are reported as a function of temperature for bis[m-(m-phenoxyphenoxy)phenyl] ether and m-phenoxyphenyl-m-(m-phenoxyphenoxy)phenyl ether. The decay curves were analysed in terms of three lifetime components; two short lifetimes of typically 200 and 500 ps associated...

  15. Induced production of halogenated diphenyl ethers from the marine-derived fungus Penicillium chrysogenum.

    Science.gov (United States)

    Yang, Guohua; Yun, Keumja; Nenkep, Viviane N; Choi, Hong Dae; Kang, Jung Sook; Son, Byeng Wha

    2010-11-01

    Manipulation of the fermentation of the marine-derived fungus Penicillium chrysogenum by addition of CaBr(2) resulted in induced production of bromodiphenyl ether analogs. Two new free-radical-scavenging polybrominated diphenyl ethers, 1 and 2, and three known diphenyl ethers, 3,3'-dihydroxy-5,5'-dimethyldiphenyl ether (3), and an inseparable mixture of violacerol-I (4) and violacerol-II (5) were isolated. The structures of the two new polybromodiphenyl ethers 1 and 2 were assigned by combined spectroscopic-data analysis, including deuterium-induced isotope effect. Compounds 1-3, and a mixture of 4 and 5 exhibited radical-scavenging activities against 1,1-diphenyl-2-picrylhydrazyl with IC(50) values of 18, 15, 42, and 6 μM, respectively. With the exception of 3, the compounds were, therefore, more active than the positive control, ascorbic acid (IC(50) 20 μM).

  16. Degradation of Perfluorinated Ether Lubricants on Pure Aluminum Surfaces: Semiempirical Quantum Chemical Modeling

    Science.gov (United States)

    Slaby, Scott M.; Ewing, David W.; Zehe, Michael J.

    1997-01-01

    The AM1 semiempirical quantum chemical method was used to model the interaction of perfluoroethers with aluminum surfaces. Perfluorodimethoxymethane and perfluorodimethyl ether were studied interacting with aluminum surfaces, which were modeled by a five-atom cluster and a nine-atom cluster. Interactions were studied for edge (high index) sites and top (low index) sites of the clusters. Both dissociative binding and nondissociative binding were found, with dissociative binding being stronger. The two different ethers bound and dissociated on the clusters in different ways: perfluorodimethoxymethane through its oxygen atoms, but perfluorodimethyl ether through its fluorine atoms. The acetal linkage of perfluorodimeth-oxymethane was the key structural feature of this molecule in its binding and dissociation on the aluminum surface models. The high-index sites of the clusters caused the dissociation of both ethers. These results are consistent with the experimental observation that perfluorinated ethers decompose in contact with sputtered aluminum surfaces.

  17. Oil recovery with sulfomethylated poly (lower alkyl vinyl ether/maleic anhydride)

    Energy Technology Data Exchange (ETDEWEB)

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

    1973-05-22

    Lower alkyl vinyl ether e.g., methyl vinyl ether, propyl vinyl ether, isopropyl vinyl ether, hexyl vinyl ether, is copolymerized conventionally with maleic anhydride, the resulting copolymer is treated with ammonia or ammonium hydroxide to form the partial amide-ammonium salt, and this salt is in turn treated with formaldehyde and thereafter or simultaneously with ammonium or alkali metal salt sulfite (including bisulfites, etc.) to form an at least partially sulfomethylated copolymer. Aqueous solutions of the sulfomethylated copolymer are useful in increasing the viscosity of drive fluids used in the supplemented recovery of petroleum from subterranean formations. In general, enhancing the polyionic character of mobility control agents used in supplemented recovery of petroleum provides enhanced recovery. Achieving this enhancement of polyionic character through use of sulfonate groups provides a mobility control agent with good ability to sustain viscosity in the presence of brine and lime, usually present in the connate waters of petroleum-bearing formations. (7 claims)

  18. Williamson alkylation approach to the synthesis of poly(alkyl vinyl ether) copolymers

    International Nuclear Information System (INIS)

    Markova, D.; Christova, D.; Velichkova, R.

    2008-01-01

    A method for synthesis of poly(alkyl vinyl ether-co-vinyl alcohol) copolymers was developed based on the Williamson's alkylation of poly(vinyl acetate) (PVAc) with alkyl iodides. The influence of the alkylating agent and the reaction conditions on the efficiency of the modification reaction was investigated. The copolymers obtained were characterized by means of 1 H NMR and GPC. It was proved that by applying the proposed method copolymers of different composition and properties containing methyl vinyl ether, ethyl vinyl ether as well as n-butyl vinyl ether units could be prepared. Poly(methyl vinyl ether-co-vinyl alcohol)s of high degree of methylation exhibit sharp temperature response at 38-39 deg C in aqueous solution typical of the so-called smart polymers. (authors)

  19. Electrochemical investigation of sulfonated poly(ether ether ketone)/clay nanocomposite membranes for moderate temperature fuel cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Hasani-Sadrabadi, Mohammad Mahdi [Polymer Engineering Department, Amirkabir University of Technology, Tehran (Iran); Biomedical Engineering Department, Amirkabir University of Technology, Tehran (Iran); Dashtimoghadam, Erfan; Sarikhani, Kaveh [Polymer Engineering Department, Amirkabir University of Technology, Tehran (Iran); Majedi, Fatemeh S. [Biomedical Engineering Department, Amirkabir University of Technology, Tehran (Iran); Khanbabaei, Ghader [Polymer Science and Technology Division, Research Institute of Petroleum Industry, Tehran (Iran)

    2010-05-01

    In the present study, polyelectrolyte membranes based on partially sulfonated poly(ether ether ketone) (sPEEK) with various degrees of sulfonation are prepared. The optimum degree of sulfonation is determined according to the transport properties and hydrolytic stability of the membranes. Subsequently, various amounts of the organically modified montmorillonite (MMT) are introduced into the sPEEK matrices via the solution intercalation technique. The proton conductivity and methanol permeability measurements of the fabricated composite membranes reveal a high proton to methanol selectivity, even at elevated temperatures. Membrane based on sPEEK and 1 wt% of MMT, as the optimum nanoclay composition, exhibits a high selectivity and power density at the concentrated methanol feed. Moreover, it is found that the optimum nanocomposite membrane not only provides higher performance compared to the neat sPEEK and Nafion {sup registered} 117 membranes, but also exhibits a high open circuit voltage (OCV) at the elevated methanol concentration. Owing to the high proton conductivity, reduced methanol permeability, high power density, convenient processability and low cost, sPEEK/MMT nanocomposite membranes could be considered as the alternative membranes for moderate temperature direct methanol fuel cell applications. (author)

  20. Novel sulfonated poly (ether ether keton)/polyetherimide acid-base blend membranes for vanadium redox flow battery applications

    International Nuclear Information System (INIS)

    Liu, Shuai; Wang, Lihua; Ding, Yue; Liu, Biqian; Han, Xutong; Song, Yanlin

    2014-01-01

    Highlights: • SPEEK/PEI acid-base blend membranes are prepared for VRB applications. • The acid-base blend membranes have much lower vanadium ion permeability. • The energy efficiency of SPEEK/PEI maintain around 86.9% after 50 cycles. - Abstract: Novel acid-base blend membranes composed of sulfonated poly (ether ether ketone) (SPEEK) and polyetherimide (PEI) were prepared for vanadium redox flow battery (VRB). The blend membranes were characterized by Fourier transform infrared spectroscopy (FT-IR) and scanning electronic microscopy (SEM). The ion exchange capacity (IEC), proton conductivity, water uptake, vanadium ion permeability and mechanical properties were measured. As a result, the acid-base blend membranes exhibit higher water uptake, IEC and lower vanadium ion permeability compared to Nafion117 membranes and all these properties decrease with the increase of PEI. In VRB single cell test, the VRB with blend membranes shows lower charge capacity loss, higher coulombic efficiency (CE) and energy efficiency (EE) than Nafion117 membrane. Furthermore, the acid-base blend membranes present stable performance up to 50 cycles with no significant decline in CE and EE. All experimental results indicate that the SPEEK/PEI (S/P) acid-base blend membranes show promising prospects for VRB

  1. Novel proton exchange membranes based on structure-optimized poly(ether ether ketone ketone)s and nanocrystalline cellulose

    Science.gov (United States)

    Ni, Chuangjiang; Wei, Yingcong; Zhao, Qi; Liu, Baijun; Sun, Zhaoyan; Gu, Yan; Zhang, Mingyao; Hu, Wei

    2018-03-01

    Two sulfonated fluorenyl-containing poly(ether ether ketone ketone)s (SFPEEKKs) were synthesized as the matrix of composite proton exchange membranes by directly sulfonating copolymer precursors comprising non-sulfonatable fluorinated segments and sulfonatable fluorenyl-containing segments. Surface-modified nanocrystalline cellulose (NCC) was produced as the "performance-enhancing" filler by treating the microcrystalline cellulose with acid. Two families of SFPEEKK/NCC nanocomposite membranes with various NCC contents were prepared via a solution-casting procedure. Results revealed that the insertion of NCC at a suitable ratio could greatly enhance the proton conductivity of the pristine membranes. For example, the proton conductivity of SFPEEKK-60/NCC-4 (SFPEEKK with 60% fluorenyl segments in the repeating unit, and inserted with 4% NCC) composite membrane was as high as 0.245 S cm-1 at 90 °C, which was 61.2% higher than that of the corresponding pure SFPEEKK-60 membrane. This effect could be attributed to the formation of hydrogen bond networks and proton conduction paths through the interaction between -SO3H/-OH groups on the surface of NCC particles and -SO3H groups on the SFPEEKK backbones. Furthermore, the chemically modified NCC filler and the optimized chemical structure of the SFPEEKK matrix also provided good dimensional stability and mechanical properties of the obtained nanocomposites. In conclusion, these novel nanocomposites can be promising proton exchange membranes for fuel cells at moderate temperatures.

  2. Low-Temperature Oxidation of Dimethyl Ether to Polyoxymethylene Dimethyl Ethers over CNT-Supported Rhenium Catalyst

    Directory of Open Access Journals (Sweden)

    Qingde Zhang

    2016-03-01

    Full Text Available Due to its excellent conductivity, good thermal stability and large specific surface area, carbon nano-tubes (CNTs were selected as support to prepare a Re-based catalyst for dimethyl ether (DME direct oxidation to polyoxymethylene dimethyl ethers (DMMx. The catalyst performance was tested in a continuous flow type fixed-bed reactor. H3PW12O40 (PW12 was used to modify Re/CNTs to improve its activity and selectivity. The effects of PW12 content, reaction temperature, gas hourly space velocity (GHSV and reaction time on DME oxidation to DMMx were investigated. The results showed that modification of CNT-supported Re with 30% PW12 significantly increased the selectivity of DMM and DMM2 up to 59.0% from 6.6% with a DME conversion of 8.9%; besides that, there was no COx production observed in the reaction under the optimum conditions of 513 K and 1800 h−1. The techniques of XRD, BET, NH3-TPD, H2-TPR, XPS, TEM and SEM were used to characterize the structure, surface properties and morphology of the catalysts. The optimum amount of weak acid sites and redox sites promotes the synthesis of DMM and DMM2 from DME direct oxidation.

  3. Synthesis and Characterization of Sulfonated Graphene Oxide Reinforced Sulfonated Poly (Ether Ether Ketone (SPEEK Composites for Proton Exchange Membrane Materials

    Directory of Open Access Journals (Sweden)

    Ning Cao

    2018-03-01

    Full Text Available As a clean energy utilization device, full cell is gaining more and more attention. Proton exchange membrane (PEM is a key component of the full cell. The commercial-sulfonated, tetrafluoroethylene-based fluoropolymer-copolymer (Nafion membrane exhibits excellent proton conductivity under a fully humidified environment. However, it also has some disadvantages in practice, such as high fuel permeability, a complex synthesis process, and high cost. To overcome these disadvantages, a low-cost and novel membrane was developed. The sulfonated poly (ether ether ketone (SPEEK was selected as the base material of the proton exchange membrane. Sulfonated graphene (SG was cross-linked with SPEEK through the elimination reaction of hydrogen bonds. It was found that the sulfonic acid groups and hydrophilic oxygen groups increased obviously in the resultant membrane. Compared with the pure SPEEK membrane, the SG-reinforced membrane exhibited better proton conductivity and methanol permeability prevention. The results indicate that the SG/SPEEK could be applied as a new proton exchange membrane in fuel cells.

  4. Highly stable ionic-covalent cross-linked sulfonated poly(ether ether ketone) for direct methanol fuel cells

    Science.gov (United States)

    Lei, Linfeng; Zhu, Xingye; Xu, Jianfeng; Qian, Huidong; Zou, Zhiqing; Yang, Hui

    2017-05-01

    A novel ionic cross-linked sulfonated poly(ether ether ketone) containing equal content of sulfonic acid and pendant tertiary amine groups (TA-SPEEK) has been initially synthesized for the application in direct methanol fuel cells (DMFCs). By adjusting the ratio of p-xylene dibromide to tertiary amine groups of TA-SPEEK, a series of ionic-covalent cross-linked membranes (C-SPEEK-x) with tunable degree of cross-linking are prepared. Compared with the pristine membrane, the ionic and ionic-covalent cross-linked proton exchange membranes (PEMs) exhibit reduced methanol permeability and improved mechanical properties, dimensional and oxidative stability. The proton conductivity and methanol selectivity of protonated TA-SPEEK and C-SPEEK-x at 25 °C is up to 0.109 S cm-1 and 3.88 × 105 S s cm-3, respectively, which are higher than that of Nafion 115. The DMFC incorporating C-SPEEK-25 exhibits a maximum power density as high as 35.3 mW cm-2 with 4 M MeOH at 25 °C (31.8 mW cm-2 for Nafion 115). Due to the highly oxidative stability of the membrane, no obvious performance degradation of the DMFC is observed after more than 400 h operation, indicating such cost-effective ionic-covalent cross-linked membranes have substantial potential as alternative PEMs for DMFC applications.

  5. Molecular motions of non-crystalline poly(aryl ether-ether-ketone) PEEK and influence of electron beam irradiation

    International Nuclear Information System (INIS)

    Sasuga, T.; Hagiwara, M.

    1985-01-01

    The dynamic mechanical relaxation of non-crystalline poly(aryl ether-ether-ketone) PEEK and the one irradiated with electron beam were studied. The three distinct γ, β, α' relaxation maxima were observed in unirradiated PEEK from low to high temperature. It was revealed from the study on the irradiation effects that three different molecular processes are overlapped in γ relaxation peak, i.e., molecular motion of water bound to main chain, local motion of main chain, and local mode of the aligned and/or oriented moiety. The β relaxation connected with the glass transition occurred at 150 deg C and it shifted to higher temperature by irradiation. The α' relaxation which can be attributed to rearrangement of molecular chain due to crystallization was observed in unirradiated PEEK approx. 180 deg C and its magnitude decreased with the increase in irradiation dose. This effect indicates the formation of structures inhibiting crystallization such as crosslinking and/or short branching during irradiation. A new relaxation, β', appeared in the temperature range of 40 deg to 100 deg C by irradiation and its magnitude increased with dose. This relaxation was attributed to rearrangement of molecular chain from loosened packing around chain ends, which were introduced into the non-crystalline region by chain scission under irradiation, to more rigid molecular packing. (author)

  6. Effect of chemical etching on the Cu/Ni metallization of poly (ether ether ketone)/carbon fiber composites

    International Nuclear Information System (INIS)

    Di Lizhi; Liu Bin; Song Jianjing; Shan Dan; Yang Dean

    2011-01-01

    Poly(ether ether ketone)/carbon fiber composites (PEEK/Cf) were chemical etched by Cr 2 O 3 /H 2 SO 4 solution, electroless plated with copper and then electroplated with nickel. The effects of chemical etching time and temperature on the adhesive strength between PEEK/Cf and Cu/Ni layers were studied by thermal shock method. The electrical resistance of some samples was measured. X-ray photoelectron spectroscopy (XPS) was used to analyze the surface composition and functional groups. Scanning electron microscopy (SEM) was performed to observe the surface morphology of the composite, the chemical etched sample, the plated sample and the peeled metal layer. The results indicated that C=O bond increased after chemical etching. With the increasing of etching temperature and time, more and more cracks and partially exposed carbon fibers appeared at the surface of PEEK/Cf composites, and the adhesive strength increased consequently. When the composites were etched at 60 deg. C for 25 min and at 70-80 deg. C for more than 15 min, the Cu/Ni metallization layer could withstand four thermal shock cycles without bubbling, and the electrical resistivity of the metal layer of these samples increased with the increasing of etching temperature and time.

  7. Nanocomposite Based on Functionalized Gold Nanoparticles and Sulfonated Poly(ether ether ketone Membranes: Synthesis and Characterization

    Directory of Open Access Journals (Sweden)

    Iole Venditti

    2017-03-01

    Full Text Available Gold nanoparticles, capped by 3-mercapto propane sulfonate (Au-3MPS, were synthesized inside a swollen sulfonated poly(ether ether ketone membrane (sPEEK. The formation of the Au-3MPS nanoparticles in the swollen sPEEK membrane was observed by spectroscopic and microscopic techniques. The nanocomposite containing the gold nanoparticles grown in the sPEEK membrane, showed the plasmon resonance λmax at about 520 nm, which remained stable over a testing period of three months. The size distribution of the nanoparticles was assessed, and the sPEEK membrane roughness, both before and after the synthesis of nanoparticles, was studied by AFM. The XPS measurements confirm Au-3MPS formation in the sPEEK membrane. Moreover, AFM experiments recorded in fluid allowed the production of images of the Au-3MPS@sPEEK composite in water at different pH levels, achieving a better understanding of the membrane behavior in a water environment; the dynamic hydration process of the Au-3MPS@sPEEK membrane was investigated. These preliminary results suggest that the newly developed nanocomposite membranes could be promising materials for fuel cell applications.

  8. A new interpretation of SAXS peaks in sulfonated poly(ether ether ketone) (sPEEK) membranes for fuel cells.

    Science.gov (United States)

    Mendil-Jakani, H; Zamanillo Lopez, I; Legrand, P M; Mareau, V H; Gonon, L

    2014-06-21

    The structure of a commercial sulfonated poly(ether ether ketone) (sPEEK) membrane was analyzed by Small-Angle X-Ray Scattering (SAXS) for different water uptakes obtained after immersion in liquid water at various temperatures. For low membrane swelling, the SAXS profile displays only a wide-angle peak in the 0.2-0.3 Å(-1) region. As the membrane swells, two supplementary correlation peaks arise and shift towards small angles, which are the signature of a structural evolution of the membrane, whereas the wide angle peak remains stable. The SAXS spectra of sPEEK membranes can thus display three correlation peaks simultaneously. Therefore we propose a new interpretation of these SAXS spectra which conclude that the two small angle peaks are attributed to the so-called matrix and ionomer peaks and the wide-angle peak is ascribed to the mean separation distance between sulfonic acid groups grafted onto the polymer backbone. This peak attribution implies that the sPEEK nano-phase separation is triggered by an immersion in hot water (ionomer peak apparition). Our new peak attribution was confirmed by studying the impact of temperature, electron density contrast and ionic exchange capacity.

  9. Effect of surface finishing on friction and wear of Poly-Ether-Ether-Ketone (PEEK under oil lubrication

    Directory of Open Access Journals (Sweden)

    Thiago Fontoura de Andrade

    Full Text Available Abstract The tribological properties of poly-ether-ether-ketone (PEEK containing 30% of carbon fiber were studied in an oil-lubricated environment and different surface finishing of the metallic counterbody. Four different finishing processes, commonly used in the automotive industry, were chosen for this study: turning, grinding, honing and polishing. The test system used was tri-pin on disc with pins made of PEEK and counterbody made of steel; they were fully immersed in ATF Dexron VI oil. Some test parameters were held constant, such as the apparent pressure of 2 MPa, linear velocity of 2 m/s, oil temperature at 85 °C, and the time - 120 minutes. The lubrication regime for the apparent pressure of 1 MPa to 7 MPa range was also studied at different sliding speeds. A direct correlation was found between the wear rate, friction coefficient and the lubrication regime, wherein wear under hydrodynamic lubrication was, on average, approximately 5 times lower, and the friction coefficient 3 times lower than under boundary lubrication.

  10. Environment effects on the optical properties of some fluorinated poly(oxadiazole ether)s in binary solvent mixtures

    International Nuclear Information System (INIS)

    Homocianu, Mihaela; Ipate, Alina Mirela; Hamciuc, Corneliu; Airinei, Anton

    2015-01-01

    The solvatochromic behavior of some fluorinated poly(oxadiazole ether)s was studied using UV–vis absorption and fluorescence spectroscopy in neat solvents and in their solvent mixtures at several ratios of cosolvents. Quantitative investigations of the spectral changes caused by solvent polarity were discussed using the Lippert‐Mataga, Bakhshiev and Kawski–Chamma–Viallet polarity functions. Repartitioning of cosolvent between local (solvation shell) and bulk phase was investigated by means of a solvatochromic shift method in chloroform–N,N-dimethylformamide (CHCl 3 /DMF) and chloroform–dimethyl sulfoxide (CHCl 3 /DMSO) solvent mixtures. Solvatochromic properties in the binary solvent environments were predominantly influenced by the acidity and basicity of the solvent systems. The fluorescence quenching process by nitrobenzene was characterized by Stern–Volmer plots which display a positive deviation from linearity. This was explained by static and dynamic quenching mechanisms. - Highlights: • Solvatochromic behavior in solvent mixtures was studied. • Stokes shift and local environments in binary mixed solvent were discussed. • Repartitioning of cosolvent between local and bulk phase in solvent mixture has been investigated. • Fluorescence intensity was quenched in presence of nitrobenzene

  11. A subchronic dermal exposure study of diethylene glycol monomethyl ether and ethylene glycol monomethyl ether in the male guinea pig.

    Science.gov (United States)

    Hobson, D W; D'Addario, A P; Bruner, R H; Uddin, D E

    1986-02-01

    Diethylene glycol monomethyl ether (DEGME) has been selected as a replacement anti-icing additive for ethylene glycol monomethyl ether (EGME) in Navy jet aircraft fuel. This experiment was performed to determine whether DEGME produced similar toxicity to EGME following dermal exposure. Male guinea pigs were dermally exposed to 1.00, 0.20, 0.04, or 0 (control) g/kg/day DEGME for 13 weeks, 5 days/week, 6 hr/day. Another group of animals was similarly exposed to 1.00 g/kg/day EGME. Body weights as well as testicular and splenic weights were reduced as a result of exposure to EGME, DEGME-exposed animals exhibited decreased splenic weight in the high- and medium-dose (1.00 and 0.20 g/kg/day) exposure groups only. Hematologic changes in EGME-exposed animals included mild anemia with increased erythrocytic mean corpuscular volumes and a lymphopenia with increased neutrophils. Similar hematological changes were not observed in any animals exposed to DEGME. Serum creatine kinase activity was increased in animals exposed to EGME, and serum lactate dehydrogenase activity was increased in EGME and 1.00 g/kg/day DEGME-exposed animals. In general, DEGME produced minimal toxicological changes following dermal exposure, whereas the toxicological changes observed following similar exposure to EGME were much more profound.

  12. Simultaneous preconcentration of copper, zinc, cadmium, and nickel in water samples by cloud point extraction using 4-(2-pyridylazo)-resorcinol and their determination by inductively coupled plasma optic emission spectrometry

    International Nuclear Information System (INIS)

    Silva, Edson Luiz; Santos Roldan, Paulo dos; Gine, Maria Fernanda

    2009-01-01

    A procedure for simultaneous separation/preconcentration of copper, zinc, cadmium, and nickel in water samples, based on cloud point extraction (CPE) as a prior step to their determination by inductively coupled plasma optic emission spectrometry (ICP-OES), has been developed. The analytes reacted with 4-(2-pyridylazo)-resorcinol (PAR) at pH 5 to form hydrophobic chelates, which were separated and preconcentrated in a surfactant-rich phase of octylphenoxypolyethoxyethanol (Triton X-114). The parameters affecting the extraction efficiency of the proposed method, such as sample pH, complexing agent concentration, buffer amount, surfactant concentration, temperature, kinetics of complexation reaction, and incubation time were optimized and their respective values were 5, 0.6 mmol L -1 , 0.3 mL, 0.15% (w/v), 50 deg. C, 40 min, and 10 min for 15 mL of preconcentrated solution. The method presented precision (R.S.D.) between 1.3% and 2.6% (n = 9). The concentration factors with and without dilution of the surfactant-rich phase for the analytes ranged from 9.4 to 10.1 and from 94.0 to 100.1, respectively. The limits of detection (L.O.D.) obtained for copper, zinc, cadmium, and nickel were 1.2, 1.1, 1.0, and 6.3 μg L -1 , respectively. The accuracy of the procedure was evaluated through recovery experiments on aqueous samples.

  13. Determinação espectrofotométrica indireta de capsaicinoides em pimentas Capsicum a partir da reação com o complexo de Co(II com 4-(2-piridilazo resorcinol

    Directory of Open Access Journals (Sweden)

    Patrícia Tonon de Souza

    2014-01-01

    Full Text Available Capsaicinoids (CAPS are substances responsible for pungency in Capsicum. It is important to quantify these types of compounds owing to their broad application in food, pharmaceuticals, cosmetics and chemical weapons. In this work, we developed an indirect spectrophotometric method based on the colorimetric reaction between CAPS, Co(II 3.10×10-5 mol L-1 and 4-(2-pyridylazo resorcinol (PAR 6.23×10-5 and, in cachaça:water 92:8v/v solutions, for quantification of total CAPS in Capsicum peppers. The product of the reaction is CoPAR2CAPS2 and its absorption in aquo-ethanolic solution at 510 nm is proportional to the total CAPS concentration from 0.60 to 17.94 mg L-1. The values of limit of detection and limit of quantification were 0.0004 and 0.001 mg of CAPS/g of pepper, respectively, with 4% relative standard deviation. The developed method yielded similar results to those obtained from high performance liquid chromatography, with 95% of confidence.

  14. A simple and low cost dual-wavelength β-correction spectrophotometric determination and speciation of mercury(II) in water using chromogenic reagent 4-(2-thiazolylazo) resorcinol

    Science.gov (United States)

    Al-Bagawi, A. H.; Ahmad, W.; Saigl, Z. M.; Alwael, H.; Al-Harbi, E. A.; El-Shahawi, M. S.

    2017-12-01

    The most common problems in spectrophotometric determination of various complex species originate from the background spectral interference. Thus, the present study aimed to overcome the spectral matrix interference for the precise analysis and speciation of mercury(II) in water by dual-wavelength β-correction spectrophotometry using 4-(2-thiazolylazo) resorcinol (TAR) as chromogenic reagent. The principle was based on measuring the correct absorbance for the formed complex of mercury(II) ions with TAR reagent at 547 nm (lambda max). Under optimized conditions, a linear dynamic range of 0.1-2.0 μg mL- 1 with correlation coefficient (R2) of 0.997 were obtained with lower limits of detection (LOD) of 0.024 μg mL- 1 and limit of quantification (LOQ) of 0.081 μg mL- 1. The values of RSD and relative error (RE) obtained for β-correction method and single wavelength spectrophotometry were 1.3, 1.32% and 4.7, 5.9%, respectively. The method was validated in tap and sea water in terms of the data obtained from inductively coupled plasma-optical emission spectrometry (ICP-OES) using student's t and F tests. The developed methodology satisfactorily overcomes the spectral interference in trace determination and speciation of mercury(II) ions in water.

  15. Biosynthesis of ether-phospholipids including plasmalogens, peroxisomes and human disease: new insights into an old problem

    NARCIS (Netherlands)

    Wanders, Ronald J. A.; Brites, Pedro

    2010-01-01

    Ether-phospholipids represent an important subclass of phospholipids in animal cell membranes characterized by the presence of an ether bond at the sn-I position and the enrichment of PUFAs at the sn-2 position. Of the different ether-phospholipids, plasmalogens are the most abundant form and their

  16. Synthesis and Characterization of New ‎Condensation Polymers Based on New ‎Aromatic di-ethers

    Directory of Open Access Journals (Sweden)

    Saadon Abdulla Aowda

    2017-11-01

    Full Text Available This research includes synthesis and identification of new polymers that are expected having industrial applications in paint ships and dyes. These polymers were prepared from cheap and available materials such as glycerol and catechol, hydroquinone and resorcinol and using cheap catalyst in good yields.       The resulting compounds were identified by FT-IR, 1H-NMR, 13C-NMR, CHN, and DSC techniques. Some physical properties of these compounds were studied

  17. Calorimetric study of binding of some disaccharides with crown ethers

    Energy Technology Data Exchange (ETDEWEB)

    Davydova, Olga I.; Lebedeva, Nataliya Sh.; Parfenyuk, Elena V

    2004-11-01

    Isothermal titration calorimetry has been applied to the determination of the thermodynamic parameters of binding of {beta}-lactose, {alpha},{alpha}-trehalose and sucrose with 15-crown-5 and 18-crown-6 in water at 298.15 K. The formation of 1:1 molecular associates has been found for the systems studied except 18-crown-6 and {beta}-lactose. The associates are preferentially or completely entropy stabilized. The most stable associate is formed between {alpha},{alpha}-trehalose and 18-crown-6. The obtained values of thermodynamic parameters of binding are discussed from the point of view of solute-solvent interactions as well as conformational and structural peculiarities of the disaccharides (DS) and crown ethers (CE)

  18. Optimised mounting conditions for poly (ether sulfone) in radiation detection.

    Science.gov (United States)

    Nakamura, Hidehito; Shirakawa, Yoshiyuki; Sato, Nobuhiro; Yamada, Tatsuya; Kitamura, Hisashi; Takahashi, Sentaro

    2014-09-01

    Poly (ether sulfone) (PES) is a candidate for use as a scintillation material in radiation detection. Its characteristics, such as its emission spectrum and its effective refractive index (based on the emission spectrum), directly affect the propagation of light generated to external photodetectors. It is also important to examine the presence of background radiation sources in manufactured PES. Here, we optimise the optical coupling and surface treatment of the PES, and characterise its background. Optical grease was used to enhance the optical coupling between the PES and the photodetector; absorption by the grease of short-wavelength light emitted from PES was negligible. Diffuse reflection induced by surface roughening increased the light yield for PES, despite the high effective refractive index. Background radiation derived from the PES sample and its impurities was negligible above the ambient, natural level. Overall, these results serve to optimise the mounting conditions for PES in radiation detection. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Polybrominated diphenyl ethers in Mississippi River suspended sediment

    Energy Technology Data Exchange (ETDEWEB)

    Raff, J.; Hites, R. [Indiana Univ., Bloomington, IN (United States)

    2004-09-15

    The Mississippi River Basin drains water from 41% of the conterminous U.S. and is a valuable resource that supplies food, transportation, and irrigation to more than 95 million people of the region. Discharge and runoff from industry, agriculture, and population centers have increased the loads of anthropogenic organic compounds in the river. There has been growing concern over the rising levels of polybrominated diphenyl ethers (PBDEs) in air, sediment, biota, and humans, but there have been no studies to measure the concentrations of these chemicals in North America's largest river system. The goal of this study was to investigate the occurrence of PBDEs (15 congeners including BDE-209) and to identify possible sources within the Mississippi River Basin. We found PBDEs to be widespread throughout the region, rivaling PCBs in their extent and magnitude of contamination. We have also calculated the total amount of PBDEs released to the Gulf of Mexico in 2002.

  20. Poly (ether imide sulfone) membranes from solutions in ionic liquids

    KAUST Repository

    Kim, Dooli

    2017-11-20

    A membrane manufacture method based on non-volatile solvents and a high performance polymer, poly (ether imide sulfone) (EXTEM™), is proposed, as greener alternative to currently industrial process. We dissolved EXTEM™ in pure ionic liquids: 1-ethyl-3-methylimidalzolium thiocyanate ([EMIM]SCN), 1-butyl-3-methylimidalzolium thiocyanate ([BMIM]SCN), and 1-ethyl-3-methylimidalzolium acetate ([EMIM]OAc). The following polymer solution parameters were evaluated to optimize the manufacture: Gibbs free energy of mixing (G), intrinsic viscosity ([]) and hydrodynamic diameter. Membranes with sponge-like structure and narrow pore size distribution were obtained from solutions in [EMIM]SCN. They were tested for separation of proteins and deoxyribonucleic acids (DNA). Due to the polymer stability, we foresee that applications in more demanding chemical separations would be possible. [EMIM]SCN was 96 % purified and recovered after the membrane fabrication, contributing to the sustainability of the whole manufacturing process.

  1. 18F-fluorination by crown ether-metal fluoride

    International Nuclear Information System (INIS)

    Irie, T.; Fukushi, K.; Ido, T.; Kasida, Y.; Nozaki, T.

    1984-01-01

    For non-carrier-added 18 F-labeling of organic compounds, details were studied concerning the previously developed KF-crown ether method. In the modified method, a minute amount of KOH instead of carrier KF is added for the preparation of the anhydrous 18 F from aqueous carrier-free 18 F. The following factors were examined in order to determine optimum conditions for the preparation of the anhydrous non-carrier-added 18 F and the labeling synthesis with it: effects of the vessel on the evaporation of the 18 F-KOH solution and the amount of added KOH for the conversion of aqueous 18 F to anhydrous 18 F, the solubilized activity of the 18 F obtained by the evaporation in organic solutions containing 18-Crown-6 and the labeling reaction, as exemplified by the synthesis of 21-fluoroprogesterone. (author)

  2. Fragmentation of dimethyl ether in femtosecond intense field

    Science.gov (United States)

    Zhu, Jingyi; Guo, Wei; Wang, Yanqiu; Wang, Li

    2006-08-01

    The fragmentation of dimethyl ether (DME) in intense femtosecond laser field has been studied at 810, 405 and 270 nm with intensities up to 2.48 × 10 15, 3.86 × 10 15 and 1.62 × 10 14 W/cm 2, respectively. At 405 nm, DME is possibly firstly ionized by multiphoton absorption, and then parent ion DME + dissociates into fragments via filed-induced dissociation. For 810 and 270 nm laser fields, DME firstly dissociates into CH 3O and CH 3 fragments and then these neutral fragments are ionized by field tunneling. Another possible way for DME to dissociate at 810 and 270 nm is that DME is ionized by intense field ejection of inner valance electron and then the excited DME + dissociates into fragment ions. Ultrafast rearrangement of DME or DME + in intense field may be responsible to the unpredictable fragment ions, CHO+/C2H5+andH2+.

  3. Determination of radiostrontium in soil samples using a crown ether

    Energy Technology Data Exchange (ETDEWEB)

    Vajda, N; Ghods-Esphahani, A; Danesi, P R [International Atomic Energy Agency, Agency' s Laboratories, Chemistry Unit, PCI Laboratory, Seibersdorf (Austria)

    1995-07-01

    A simple and rapid method has been developed for the separation and successive determination of total radiostrontium in soil. The method consists of three basic steps: oxalate precipitation to remove bulk potassium, chromatographic separation of strontium from most inactive and radioactive interferences utilizing a crown ether (Sr. Spec, EIChroM Industries, II. USA), oxalate precipitation of strontium to evaluate the chemical yield. Radiostrontium is then determined by liquid scintillation counting of the dissolved precipitate. When 10 g samples of soil are used the sensitivity of the method is about 10 Bq/kg. The chemical yield is about 80%. The separation and determination of radiostrontium can be carried out in about 8 hours. (author)

  4. Determination of radiostrontium in soil samples using a crown ether

    International Nuclear Information System (INIS)

    Vajda, N.; Ghods-Esphahani, A.; Danesi, P.R.

    1995-01-01

    A simple and rapid method has been developed for the separation and successive determination of total radiostrontium in soil. The method consists of three basic steps: oxalate precipitation to remove bulk potassium, chromatographic separation of strontium from most inactive and radioactive interferences utilizing a crown ether (Sr. Spec, EIChroM Industries, II. USA), oxalate precipitation of strontium to evaluate the chemical yield. Radiostrontium is then determined by liquid scintillation counting of the dissolved precipitate. When 10 g samples of soil are used the sensitivity of the method is about 10 Bq/kg. The chemical yield is about 80%. The separation and determination of radiostrontium can be carried out in about 8 hours. (author)

  5. Calorimetric study of binding of some disaccharides with crown ethers

    International Nuclear Information System (INIS)

    Davydova, Olga I.; Lebedeva, Nataliya Sh.; Parfenyuk, Elena V.

    2004-01-01

    Isothermal titration calorimetry has been applied to the determination of the thermodynamic parameters of binding of β-lactose, α,α-trehalose and sucrose with 15-crown-5 and 18-crown-6 in water at 298.15 K. The formation of 1:1 molecular associates has been found for the systems studied except 18-crown-6 and β-lactose. The associates are preferentially or completely entropy stabilized. The most stable associate is formed between α,α-trehalose and 18-crown-6. The obtained values of thermodynamic parameters of binding are discussed from the point of view of solute-solvent interactions as well as conformational and structural peculiarities of the disaccharides (DS) and crown ethers (CE)

  6. Energy Storage of Polyarylene Ether Nitriles at High Temperature

    Science.gov (United States)

    Tang, Xiaohe; You, Yong; Mao, Hua; Li, Kui; Wei, Renbo; Liu, Xiaobo

    2018-03-01

    Polyarylene ether nitrile (PEN) was synthesized and used as film capacitors for energy storage at high temperature. Scanning electron microscopy observation indicated that the films of PEN have pinholes at nanoscales which restricted the energy storage properties of the material. The pinhole shadowing effect through which the energy storage properties of PEN were effectively improved to be 2.3 J/cm3 was observed by using the overlapped film of PEN. The high glass transition temperature (T g) of PEN was as high as 216 °C and PEN film showed stable dielectric constant, breakdown strength and energy storage density before the T g. The PEN films will be a potential candidate as high performance electronic storage materials used at high temperature.

  7. Substance Flow Analysis of Wastes Containing Polybrominated Diphenyl Ethers

    DEFF Research Database (Denmark)

    Vyzinkarova, Dana; Brunner, Paul H.

    2013-01-01

    materials. Therefore, end-of-life (EOL) plastic materials used for construction must be separated and properly treated, for example, in a state-of-the-art municipal solid waste (MSW) incinerator. In the case of cOctaBDE, the main flows are waste electrical and electronic equipment (WEEE) and, possibly......The present article examines flows and stocks of Stockholm Convention regulated pollutants, commercial penta- and octabrominated diphenyl ether (cPentaBDE, cOctaBDE), on a city level. The goals are to (1) identify sources, pathways, and sinks of these compounds in the city of Vienna, (2) determine...... the fractions that reach final sinks, and (3) develop recommendations for waste management to ensure their minimum recycling and maximum transfer to appropriate final sinks. By means of substance flow analysis (SFA) and scenario analysis, it was found that the key flows of cPentaBDE stem from construction...

  8. Homogeneous Charge Compression Ignition Combustion of Dimethyl Ether

    DEFF Research Database (Denmark)

    Pedersen, Troels Dyhr

    This thesis is based on experimental and numerical studies on the use of dimethyl ether (DME) in the homogeneous charge compression ignition (HCCI) combustion process. The first paper in this thesis was published in 2007 and describes HCCI combustion of pure DME in a small diesel engine. The tests...... were designed to investigate the effect of engine speed, compression ratio and equivalence ratio on the combustion timing and the engine performance. It was found that the required compression ratio depended on the equivalence ratio used. A lower equivalence ratio requires a higher compression ratio...... before the fuel is burned completely, due to lower in-cylinder temperatures and lower reaction rates. The study provided some insight in the importance of operating at the correct compression ratio, as well as the operational limitations and emission characteristics of HCCI combustion. HCCI combustion...

  9. Direct dimethyl ether high temperature polymer electrolyte membrane fuel cells

    DEFF Research Database (Denmark)

    Vassiliev, Anton; Jensen, Jens Oluf; Li, Qingfeng

    and suffers from low DME solubility in water. When the DME - water mixture is fed as vapour miscibility is no longer a problem. The increased temperature is more beneficial for the kinetics of the direct oxidation of DME than of methanol. The Open Circuit Voltage (OCV) with DME operation was 50 to 100 m......A high temperature polybenzimidazole (PBI) polymer fuel cell was fed with dimethyl ether (DME) and water vapour mixture on the anode at ambient pressure with air as oxidant. A peak power density of 79 mW/cm2 was achieved at 200°C. A conventional polymer based direct DME fuel cell is liquid fed......V higher than that of methanol, indicating less fuel crossover....

  10. Degradation of β-Aryl Ether Bonds in Transgenic Plants

    DEFF Research Database (Denmark)

    Mnich, Ewelina

    Lignin is one of the main building blocks of the plant cell wall. It tethers the cell wall by cross-linking with polysaccharides conferring mechanical strength to plants, aiding water transport and providing a mechanical barrier against pathogens. It is generated by the polymerization....... Compared to other plants grass cell walls contain elevated amount of ferulates which play a crucial role in cross-linking of polysaccharides and lignin. In addition ferulates are believed to be nucleation cites for the lignification. The bacterium Sphingomonas paucimobilis SYK6 has developed an enzyme...... of the cell wall. The aim of the study was to alter lignin structure by expression in plants of the enzymes from S. paucimobilis involved in ether bond degradation (LigDFG). Arabidopsis thaliana and Brachypodium distachyon transgenic lines were generated and characterized with respect to lignin structure...

  11. Polybrominated diphenyl ethers: occurrence, dietary exposure, and toxicology.

    Science.gov (United States)

    Darnerud, P O; Eriksen, G S; Jóhannesson, T; Larsen, P B; Viluksela, M

    2001-03-01

    Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in plastics (concentration, 5--30%) and in textile coatings. Commercial products consist predominantly of penta-, octa-, and decabromodiphenyl ether mixtures, and global PBDE production is about 40,000 tons per year. PBDEs are bioaccumulated and biomagnified in the environment, and comparatively high levels are often found in aquatic biotopes from different parts of the world. During the mid-1970--1980s there was a substantial increase in the PBDE levels with time in both sediments and aquatic biota, whereas the latest Swedish data (pike and guillemot egg) may indicate that levels are at steady state or are decreasing. However, exponentially increasing PBDE levels have been observed in mother's milk during 1972--1997. Based on levels in food from 1999, the dietary intake of PBDE in Sweden has been estimated to be 0.05 microg per day. Characteristic end points of animal toxicity are hepatotoxicity, embryotoxicity, and thyroid effects as well as maternal toxicity during gestation. Recently, behavioral effects have been observed in mice on administration of PBDEs during a critical period after birth. Based on the critical effects reported in available studies, we consider the lowest-observed-adverse-effect level (LOAEL) value of the PBDE group to be 1 mg/kg/day (primarily based on effects of pentaBDEs). In conclusion, with the scientific knowledge of today and based on Nordic intake data, the possible consumer health risk from PBDEs appears limited, as a factor of over 10(6) separates the estimated present mean dietary intake from the suggested LOAEL value. However, the presence of many and important data gaps, including those in carcinogenicity, reproduction, and developmental toxicity, as well as additional routes of exposure, make this conclusion only preliminary. Moreover, the time trend of PBDEs in human breast milk is alarming for the future.

  12. Searching for trans ethyl methyl ether in Orion KL.

    Science.gov (United States)

    Tercero, B; Cernicharo, J; López, A; Brouillet, N; Kolesniková, L; Motiyenko, R A; Margulès, L; Alonso, J L; Guillemin, J-C

    2015-10-01

    We report on the tentative detection of trans ethyl methyl ether (tEME), t-CH 3 CH 2 OCH 3 , through the identification of a large number of rotational lines from each one of the spin states of the molecule towards Orion KL. We also search for gauche-trans-n-propanol, Gt-n-CH 3 CH 2 CH 2 OH, an isomer of tEME in the same source. We have identified lines of both species in the IRAM 30 m line survey and in the ALMA Science Verification data. We have obtained ALMA maps to establish the spatial distribution of these species. Whereas tEME mainly arises from the compact ridge component of Orion, Gt-n-propanol appears at the emission peak of ethanol (south hot core). The derived column densities of these species at the location of their emission peaks are ≤(4.0 ± 0.8) × 10 15 cm -2 and ≤(1.0 ± 0.2)× 10 15 cm -2 for tEME and Gt-n-propanol, respectively. The rotational temperature is ~100 K for both molecules. We also provide maps of CH 3 OCOH, CH 3 CH 2 OCOH, CH 3 OCH 3 , CH 3 OH, and CH 3 CH 2 OH to compare the distribution of these organic saturated O-bearing species containing methyl and ethyl groups in this region. Abundance ratios of related species and upper limits to the abundances of non-detected ethers are provided. We derive an abundance ratio N (CH 3 OCH 3 )/ N (tEME) ≥ 150 in the compact ridge of Orion.

  13. DIMETHYL ETHER (DME)-FUELED SHUTTLE BUS DEMONSTRATION PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    Elana M. Chapman; Shirish Bhide; Jennifer Stefanik; Andre L. Boehman; David Klinikowski

    2003-04-01

    The objectives of this research and demonstration program are to convert a campus shuttle bus to operation on dimethyl ether, a potential ultra-clean alternative diesel fuel. To accomplish this objective, this project includes laboratory evaluation of a fuel conversion strategy, as well as, field demonstration of the DME-fueled shuttle bus. Since DME is a fuel with no lubricity (i.e., it does not possess the lubricating quality of diesel fuel), conventional fuel delivery and fuel injection systems are not compatible with dimethyl ether. Therefore, to operate a diesel engine on DME one must develop a fuel-tolerant injection system, or find a way to provide the necessary lubricity to the DME. In this project, they have chosen the latter strategy in order to achieve the objective with minimal need to modify the engine. The strategy is to blend DME with diesel fuel, to obtain the necessary lubricity to protect the fuel injection system and to achieve low emissions. The laboratory studies have included work with a Navistar V-8 turbodiesel engine, demonstration of engine operation on DME-diesel blends and instrumentation for evaluating fuel properties. The field studies have involved performance, efficiency and emissions measurements with the Champion Motorcoach ''Defender'' shuttle bus which will be converted to DME-fueling. The results include baseline emissions, performance and combustion measurements on the Navistar engine for operation on a federal low sulfur diesel fuel (300 ppm S). Most recently, they have completed engine combustion studies on DME-diesel blends up to 30 wt% DME addition.

  14. Absorption of decabromodiphenyl ether and other organohalogen chemicals by grey seals (Halichoerus grypus)

    International Nuclear Information System (INIS)

    Thomas, Gareth O.; Moss, Simon E.W.; Asplund, Lillemor; Hall, Ailsa J.

    2005-01-01

    An input-output balance study was performed for polybrominated diphenyl ethers, polychlorinated biphenyls and some organochlorine pesticides on three captive, juvenile grey seals (Halichoerus grypus). The animals were fed a diet of herring for six months, during the last three months of which this study was performed. A supplement of decabromodiphenyl ether was included in the diet during the second month of the study. Consistently high absorption (>89%) was observed for all of the chemicals studied, whereas work on other animals has generally shown high (>80%) net absorption at log K OW OW , and very low absorption of decabromodiphenyl ether. The half-life of decabromodiphenyl ether in blood was estimated to be between 8.5 and 13 days. Measurable concentrations of decabromodiphenyl ether were detected in seal blubber at the end of the study, indicating that this chemical can be stored in adipose and may bioaccumulate. Current understanding of the mechanism of absorption of organohalogen chemicals and the potential for accumulation of decabromodiphenyl ether will need reassessing in the light of these results. - Decabromodiphenyl ether is absorbed effectively from the diet by grey seals, and can be stored in the blubber even after exposure ceases

  15. The influence of water mixtures on the dermal absorption of glycol ethers

    International Nuclear Information System (INIS)

    Traynor, Matthew J.; Wilkinson, Simon C.; Williams, Faith M.

    2007-01-01

    Glycol ethers are solvents widely used alone and as mixtures in industrial and household products. Some glycol ethers have been shown to have a range of toxic effects in humans following absorption and metabolism to their aldehyde and acid metabolites. This study assessed the influence of water mixtures on the dermal absorption of butoxyethanol and ethoxyethanol in vitro through human skin. Butoxyethanol penetrated human skin up to sixfold more rapidly from aqueous solution (50%, 450 mg/ml) than from the neat solvent. Similarly penetration of ethoxyethanol was increased threefold in the presence of water (50%, 697 mg/ml). There was a corresponding increase in apparent permeability coefficient as the glycol ether concentration in water decreased. The maximum penetration rate of water also increased in the presence of both glycol ethers. Absorption through a synthetic membrane obeyed Fick's Law and absorption through rat skin showed a similar profile to human skin but with a lesser effect. The mechanisms for this phenomenon involves disruption of the stratum corneum lipid bilayer by desiccation by neat glycol ether micelles, hydration with water mixtures and the physicochemical properties of the glycol ether-water mixtures. Full elucidation of the profile of absorption of glycol ethers from mixtures is required for risk assessment of dermal exposure. This work supports the view that risk assessments for dermal contact scenarios should ideally be based on absorption data obtained for the relevant formulation or mixture and exposure scenario and that absorption derived from permeability coefficients may be inappropriate for water-miscible solvents

  16. The preparation and intramolecular radical cyclisation reactions of chiral oxyme ethers

    International Nuclear Information System (INIS)

    Booth, Susan E.; Jenkins, Paul R.

    1998-01-01

    Chiral oxime ether 2 and Oxime ester 4 have been prepared by alkylation and esterification of the oxime 1. Racemic hydroxylamine 6 and chiral hydroxylamine 10 have been synthesised from N-hydroxysuccinimide and the corresponding alcohol in the presence of diethyl azo dicarboxylate, the two product were converted into the oxime ethers 7 and 11 respectively. The intramolecular radical cyclisation reactions of these oxime ethers and esters has been studied, successful reaction was observed to produce alkyl hydroxylamines 3,8 and 12. (author)

  17. The Preparation and Intramolecular Radical Cyclisation Reactions of Chiral Oxime Ethers

    Directory of Open Access Journals (Sweden)

    Booth Susan E.

    1998-01-01

    Full Text Available Chiral oxime ether 2 and Oxime ester 4 have been prepared by alkylation and esterification of the oxime 1. Racemic hydroxylamine 6 and chiral hydroxylamine 10 have been synthesised from N-hydroxysuccinimide and the corresponding alcohol in the presence of diethylazodicarboxylate, the two products were converted into the oxime ethers 7 and 11 respectively. The intramolecular radical cyclisation reactions of these oxime ethers and esters has been studied, successful reaction was observed to produce alkyl hydroxylamines 3, 8 and 12.

  18. Phenyl ethers from cultured lichen mycobionts of Graphis scripta var. serpentina and G. rikuzensis.

    Science.gov (United States)

    Takenaka, Yukiko; Tanahashi, Takao; Nagakura, Naotaka; Hamada, Nobuo

    2003-07-01

    Spore-derived mycobionts of the lichen Graphis scripta var. serpentina and G. rikuzensis were cultivated on a malt-yeast extract medium supplemented with 10% sucrose and their metabolites were investigated. 3,3'-Dihydroxy-5,5'-dimethyldiphenyl ether was isolated from the cultures of the mycobionts of G. scripta var. serpentina, while a new phenyl ether, rikuzenol, along with two known diphenyl ethers, violaceol-I and violaceol-II, were isolated from those of G. rikuzensis. The structure of the new compound was determined by spectroscopic methods. Violaceol-I was chemically synthesized and interconversion between violaceol-I and violaceol-II was proven.

  19. Reproductive Effects of Two Polybrominated Diphenyl Ethers on the Rotifer Brachionus plicatilis.

    Science.gov (United States)

    Zhang, Jing; Wang, You; Zhou, Bin; Sun, Kai-Ming; Tang, Xuexi

    2016-08-01

    The effects of two polybrominated diphenyl ethers (PBDEs) on the reproduction of the rotifer Brachionus plicatilis were investigated. Results showed that sexual maturation was promoted by tetra-brominated diphenyl ether-47 (BDE-47) and deca-brominated diphenyl ether-209 (BDE-209), whereas fecundity was inhibited by BDE-47, but promoted by BDE-209. Additionally, both PBDEs affected the expression of two genes, vasa and nanos mRNA, related to rotifer reproduction. This suggests a possible regulatory molecular mechanism at the transcriptional level. Our research extends the current knowledge of the ecotoxicological mechanism induced by PBDEs and provides further essential information for assessing the risks of PBDE contamination in marine ecosystems.

  20. New aromatic activated dihalides and bisphenol monomers for the preparation of novel poly(arylene ethers)

    Science.gov (United States)

    Wolfe, James F.

    1993-01-01

    The goal of this research program was to synthesize a series of unique monomers of type I to be utilized at NASA-Langley in the preparation of new poly(arylene ether ketones), poly(arylene ether ketosulfones), and poly(arylene ether ketophosphine oxides). These A-A and A-B monomer systems, which possess activated aryl halide and/or phenolic end groups, are accessible via condensation reactions of appropriately substituted aryl acetonitrile carbanions with activated aryl dihalides followed by oxidative decyanation.

  1. Etched poly(ether ether ketone) jacket stir bar with detachable dumbbell-shaped structure for stir bar sorptive extraction.

    Science.gov (United States)

    Zhou, Wei; Wang, Chenlu; Wang, Xuemei; Chen, Zilin

    2018-06-08

    Development of stir bar sorptive extraction (SBSE) device with high stability and extraction efficiency is critical and challenging by date. In this work, etched poly(ether ether ketone) (PEEK) tube with high mechanical strength and large specific surface area was used as jacket for SBSE device. By etching with concentrated sulfuric acid, the smooth outer surface of PEEK become porous with plenty of micro holes, which was beneficial for coating of sorbents and significantly improved the extraction performance. After functionalized by bio-polydopamine method, strong hydrophobic p-naphtholbenzein molecular was immobilized onto the chemical resistant PEEK surface (PNB@E-PEEK) as stationary phase. We also firstly developed a simple detachable dumbbell-shaped structure for improving the workability of PEEK jacket stir bar. The dumbbell-shaped construction can eliminate the friction between stir bar and container, and the design of detachable structure make elution can be accomplished easier with small amount of organic solvent. It was interesting that the developed detachable dumbbell-shaped PNB@E-PEEK stir bar showed exceptional stability and extraction efficiency for SBSE enrichment of multiple analytes including several Sudan dyes, triazines, polycyclic aromatic hydrocarbons (PAHs), alkaloids and flavonoid. By coupling with high performance liquid chromatography-ultraviolet detection (HPLC-UV), PNB@E-PEEK stir bar based SBSE-HPLC-UV method was applied for the analysis of common Sudan dye pollutants. The method showed low limits of detection (0.02-0.03 ng/mL), good linearity (R 2  ≥ 0.9979) and good reproducibility (relative standard deviation ≤ 7.96%). It has been successfully applied to determine three dye pollutants in tap and lake water. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Dihydrogenimidazole modified silica-sulfonated poly(ether ether ketone) hybrid materials as electrolyte membranes for direct ethanol fuel cells

    International Nuclear Information System (INIS)

    Roelofs, Kimball S.; Hirth, Thomas; Schiestel, Thomas

    2011-01-01

    The present study reports on dihydrogenimidazole modified inorganic-organic mixed matrix membranes for possible application as a proton exchange membrane in direct ethanol fuel cells. The polymeric phase consisted mainly of sulfonated poly(ether ether ketone) (sPEEK) with a sulfonation degree of 55%. The inorganic phase was built up from hydrophilic fumed silica particles interconnected with partially hydrolyzed and condensed tetraethoxysilane with a total inorganic loading of 27.3%. This inorganic phase was further modified with N-(3-triethoxysilylpropyl)-4,5-dihydroimidazole (DHIM), which consists of an hydrolyzable inorganic part and a functional organic group. The influence of the modifier on the mixed matrix system was studied by means of various modifier concentrations in various aqueous-ethanolic systems (water, 2 M and 4 M ethanol). Modifier concentration and ethanol concentration of the ethanol-water mixture exhibited significant but opposite effects on the liquid uptake of the mixed matrix membranes. The proton conductivity as well as the proton diffusion coefficient as a function of modifier content showed a linear decrease. The proton conductivity as a function of temperature showed Arrhenius behavior and the activation energy of the mixed matrix membranes was 43.9 ± 2.6 kJ mol -1 . High selectivity of proton diffusion coefficient to ethanol permeability coefficient was obtained with high modifier concentrations. At low modifier concentrations, this selectivity was dominated by ethanol permeation and at high modifier concentrations by proton diffusion. The main electrolyte properties can be optimized by setting the DHIM content in mixed matrix membrane. With this approach, tailor-made membranes can be prepared for possible application in direct ethanol fuel cells.

  3. Composite electrolytes composed of Cs-substituted phosphotungstic acid and sulfonated poly(ether-ether ketone) for fuel cell systems

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Song-Yul, E-mail: ms089203@tutms.tut.ac.jp [Department of Materials Science, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 441-8580 (Japan); Yoshida, Toshihiro; Kawamura, Go [Department of Materials Science, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 441-8580 (Japan); Muto, Hiroyuki [Department of Materials Science and Engineering, Kurume National College of Technology, 1-1-1 Komorino, Kurume, Fukuoka 830-8555 (Japan); Sakai, Mototsugu [Department of Materials Science, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 441-8580 (Japan); Matsuda, Atsunori, E-mail: matsuda@tutms.tut.ac.jp [Department of Materials Science, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 441-8580 (Japan)

    2010-10-15

    Composite electrolytes composed of cesium hydrogen sulfate containing phosphotungstic acids (CsHSO{sub 4}-H{sub 3}PW{sub 12}O{sub 40}) and sulfonated poly(ether-ether ketone) (SPEEK) were prepared by casting the corresponding precursor for application in fuel cells. Partially Cs-substituted phosphotungstic acids (Cs{sub x}H{sub 3-x}PW{sub 12}O{sub 40}) were formed in the CsHSO{sub 4}-H{sub 3}PW{sub 12}O{sub 40} system by mechanochemical treatment. SPEEK was prepared from PEEK by sulfonation using concentrated sulfuric acid. Flexible composite electrolytes were obtained and their electrochemical properties were markedly improved with the addition of Cs{sub x}H{sub 3-x}PW{sub 12}O{sub 40}, into the SPEEK matrix. A maximum power density of 213 mW cm{sup -2} was obtained from the single cell test for 50H{sub 3}PW{sub 12}O{sub 40}-50CsHSO{sub 4} in SPEEK (1/5 by weight) composite electrolyte at 80 deg. C and at 80 RH%. Electrochemical properties and transmission electron microscopy (TEM) results suggest that three-dimensional cluster particles were formed and homogeneously distributed in the SPEEK matrix. The mechanochemically synthesized Cs{sub x}H{sub 3-x}PW{sub 12}O{sub 40} incorporated into the SPEEK matrix increased the number of protonate sites in the electrolyte. The composite electrolytes were successfully formed with Cs{sub x}H{sub 3-x}PW{sub 12}O{sub 40}, which consist of hydrogen bonding between surface of inorganic solid acids and not only -HSO{sub 4}{sup -} dissociated from CsHSO{sub 4} but also -SO{sub 3}H groups in the SPEEK.

  4. Dihydrogenimidazole modified silica-sulfonated poly(ether ether ketone) hybrid materials as electrolyte membranes for direct ethanol fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Roelofs, Kimball S.; Hirth, Thomas [Fraunhofer Institute for Interfacial Engineering and Biotechnology, Nobelstr. 12, 70569 Stuttgart (Germany); Schiestel, Thomas, E-mail: Thomas.Schiestel@igb.fraunhofer.de [Fraunhofer Institute for Interfacial Engineering and Biotechnology, Nobelstr. 12, 70569 Stuttgart (Germany)

    2011-05-25

    The present study reports on dihydrogenimidazole modified inorganic-organic mixed matrix membranes for possible application as a proton exchange membrane in direct ethanol fuel cells. The polymeric phase consisted mainly of sulfonated poly(ether ether ketone) (sPEEK) with a sulfonation degree of 55%. The inorganic phase was built up from hydrophilic fumed silica particles interconnected with partially hydrolyzed and condensed tetraethoxysilane with a total inorganic loading of 27.3%. This inorganic phase was further modified with N-(3-triethoxysilylpropyl)-4,5-dihydroimidazole (DHIM), which consists of an hydrolyzable inorganic part and a functional organic group. The influence of the modifier on the mixed matrix system was studied by means of various modifier concentrations in various aqueous-ethanolic systems (water, 2 M and 4 M ethanol). Modifier concentration and ethanol concentration of the ethanol-water mixture exhibited significant but opposite effects on the liquid uptake of the mixed matrix membranes. The proton conductivity as well as the proton diffusion coefficient as a function of modifier content showed a linear decrease. The proton conductivity as a function of temperature showed Arrhenius behavior and the activation energy of the mixed matrix membranes was 43.9 {+-} 2.6 kJ mol{sup -1}. High selectivity of proton diffusion coefficient to ethanol permeability coefficient was obtained with high modifier concentrations. At low modifier concentrations, this selectivity was dominated by ethanol permeation and at high modifier concentrations by proton diffusion. The main electrolyte properties can be optimized by setting the DHIM content in mixed matrix membrane. With this approach, tailor-made membranes can be prepared for possible application in direct ethanol fuel cells.

  5. Anhydrous proton exchange membrane of sulfonated poly(ether ether ketone) enabled by polydopamine-modified silica nanoparticles

    International Nuclear Information System (INIS)

    Wang, Jingtao; Bai, Huijuan; Zhang, Haoqin; Zhao, Liping; Chen, Huiling; Li, Yifan

    2015-01-01

    Highlights: • The concept of acid/base pairs was employed to design anhydrous PEMs. • Polydopamine-modified silica particles were uniformly dispersed in SPEEK membrane. • The membranes displayed enhancement in both stability and anhydrous proton conductivity. - Abstract: Novel anhydrous proton exchange membrane is (PEM) facilely prepared by embedding dopamine-modified silica nanoparticles (DSiOis 2 ) into sulfonated poly (ether ether ketone) (SPEEK) polymer matrix. DSiO 2 bearing -NH 2 /-NH- groups are synthesized inspired by the bioadhesion principle, which are uniformly dispersed within SPEEK membrane due to the good interfacial compatibility. The interfacial electrostatic attractions render unique rearrangement of the nanophase-separated structure and the chain packing of the resultant hybrid membranes. As a result, the thermal and mechanical stabilities as well as structural stability of the hybrid membranes are enhanced when compared to SPEEK control membrane. On the other hand, induced by the attractions, acid–base pairs are formed at the SPEEK/DSiOarewere 2 interface, where fast proton transfer via Grotthuss mechanism is expected. These features confer much higher proton conductivities on the DSiO 2 -filled membranes under both hydrated and anhydrous conditions, compared to those of the SPEEK control membrane and SiO 2 -filled membranes. Particularly, the hybrid membrane with 15 wt% DSiO 2 achieve the highest conductivities of 4.52achieveachieved × 10 −3 S cm −1 at 120 °C under anhydrous condition, which is much higher than the SPEEK control membrane and the commercial Nafion membrane (0.1iswas × 10 −3 S cm −1 ). The membrane with 9 wt% DSiO 2 show an open cell potential of 0.98showshowed V and an optimum power density of 111.7 mW cm −2 , indicative of its potential application in fuel cell under anhydrous condition

  6. Dispersibility and chemical bonds between multi-walled carbon nanotubes and poly(ether ether ketone) in nanocomposite fibers

    International Nuclear Information System (INIS)

    Yanmei, Jin; Haihui, Liu; Ning, Wang; Lichen, Hou; Xing-Xiang, Zhang

    2012-01-01

    A series of multi-walled carbon nanotubes (MWNTs)/poly(ether ether ketone)(PEEK) nanocomposite fibers were fabricated by mixing, melt extruding PEEK with different loadings and species of MWNTs, and melt-spun the blended chips. Nanocomposite fibers were heat-stretched and heat-treated. The morphology and dispersibility of MWNTs in nanocomposite fibers were observed using a field emission environmental scanning electron microscope (FESEM) and a transmission electron microscope (TEM). The thermal and crystallization behavior of nanocomposite fibers were characterized using differential scanning calorimetry (DSC) and an X-ray diffractometer (XRD). Mechanical properties were tested using a tensile strength tester. MWNTs tend to aggregate when the loading exceeds 0.8 wt%. Functional groups on MWNTs improve the hydrophobicity and the dispersibility of MWNTs in PEEK matrix. The enhancement of mechanical properties depends on the loading and species of functional groups. The most effectively reinforced effect is in the sequence, carboxylic MWNTs (MWNT–COOH) > hydroxyl MWNTs (MWNT–OH) > MWNTs, which can be explained by the strong hydrogen bonding and the affinity between MWNT–COOH and PEEK, MWNT–OH and PEEK, and possible formation of a chemical bond between MWNT–COOH and PEEK. A nanocomposite fiber with excellent mechanical property was fabricated using 0.8 wt% MWNT–COOH as filler. The Young's modulus is 1.7 GPa; and the stress is 648 MPa. -- Highlights: ► Functional groups on MWNTs improve their hydrophobility and dispersability. ► Mechanical properties depend on the content and species of the functional groups. ► The reinforced effect is in the sequence, carboxylic MWNTs > hydroxyl MWNTs > MWNTs. ► The strength behavior was result of hydrogen bond, affinity and chemical bond. ► Dispersability of MWNTs in matrix was analyzed by calculating solubility parameter.

  7. State of the water in crosslinked sulfonated poly(ether ether ketone). Two-dimensional differential scanning calorimetry correlation mapping

    Energy Technology Data Exchange (ETDEWEB)

    Al Lafi, Abdul G. [Department of Chemistry, Atomic Energy Commission, Damascus, P.O. Box 6091 (Syrian Arab Republic); Hay, James N., E-mail: cscientific9@aec.org.sy [The School of Metallurgy and Materials, College of Physical Sciences and Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)

    2015-07-20

    Highlights: • 2D-DSC mapping was applied to analyze the heat flow responses of hydrated crosslinked sPEEK. • Two types of loosely bond water were observed. • The first was bond to the sulfonic acid groups and increased with ion exchange capacity. • The second was attributed to the polar groups introduced by ions irradiation and increased with crosslinking degree. • DSC combined with 2D mapping provides a powerful tool for polymer structural determination. - Abstract: This paper reports the first application of two-dimensional differential scanning calorimetry correlation mapping, 2D-DSC-CM to analyze the heat flow responses of sulphonated poly(ether ether ketone), sPEEK, films having different ion exchange capacity and degrees of crosslinks. With the help of high resolution and high sensitivity of 2D-DSC-CM, it was possible to locate two types of loosely bound water within the structure of crosslinked sPEEK. The first was bound to the sulfonic acid groups and dependent on the ion exchange capacity of the sPEEK. The second was bound to other polar groups, either introduced by irradiation with ions and dependent on the crosslinking degree or present in the polymer such as the carbonyl groups or terminal units. The results suggest that the ability of the sulfonic acid groups in the crosslinked sPEEK membranes to adsorb water molecules is increased by crosslinking, probably due to the better close packing efficiency of the crosslinked samples. DSC combined with 2D correlation mapping provides a fast and powerful tool for polymer structural determination.

  8. The effect of ethylene glycol monomethyl ether and diethylene glycol monomethyl ether on hepatic gamma-glutamyl transpeptidase.

    Science.gov (United States)

    Kawamoto, T; Matsuno, K; Kayama, F; Arashidani, K; Yoshikawa, M; Kodama, Y

    1992-11-22

    In this paper, we determined whether ethylene glycol monomethyl ether (EGME) and diethylene glycol monomethyl ether (diEGME) induce hepatic gamma-glutamyl transpeptidase activity. Male adult Wistar rats weighing 220 g were used as experimental animals. EGME (100, 300 mg/kg per day) and diEGME (500, 1000, 2000 mg/kg per day) were administered by gavage for 1, 2 or 5 days or 4 weeks. In the 4-week study, experimental animals were administered EGME or diEGME once a day orally, 5 days/week. EGME treatment increased the serum gamma-glutamyl transpeptidase (GGT) level significantly, however, diEGME did not. The activities of three other enzymes (SGOT, SGPT and ALP) in serum were not altered by EGME or diEGME treatment and thus there was no biochemical indices of hepatic damage by EGME or diEGME. EGME treatment increased the GGT activities in the liver and lungs. Of the organs examined, the induction of GGT was the greatest in the liver. The inducibility in the liver was 216% for the 5-day treatment and 460% for the 4-week treatment. A dose-dependent increase of hepatic microsomal GGT activity by EGME was observed. On the other hand, renal GGT activities were declined to 72% and 60% of control by the 5-day and 4-week EGME treatments, respectively. DiEGME did not affect the GGT activities in any of the tissues except those of the brain. In the histochemical study, most hepatocytes at the periportal zones were stained with GGT staining after the 4-week treatment. However, the hepatocytes at the central zones were negative.

  9. Flourimetric and prototropic studies on the inclusion complexation of 2-amino and 4-aminodiphenyl ethers with {beta}-cyclodextrin: Unusual behavior of 4-aminodiphenyl ether

    Energy Technology Data Exchange (ETDEWEB)

    Enoch, Israel V. Muthu Vijayan [Department of Chemistry, Annamalai University, Annamalainagar 608 002, Tamil Nadu (India); Swaminathan, Meenakshisundaram [Department of Chemistry, Annamalai University, Annamalainagar 608 002, Tamil Nadu (India)], E-mail: chemsam@yahoo.com

    2007-12-15

    The fluorescence characteristics of diphenyl ether (DPE), 2-aminodiphenyl ether (2ADPE) and 4-aminodiphenyl ether (4ADPE) and prototropic behavior of 2ADPE and 4ADPE on inclusion complexation with {beta}-cyclodextrin have been investigated. DPE forms 1:1 complex whereas 2ADPE and 4ADPE form 1:2 complex with {beta}-CDx. The fluorimetric and prototropic behaviors of 4ADPE in {beta}-CDx are different from those in aqueous solution. The dual fluorescence of 4ADPE in {beta}-CDx is found to be due to twisted intramolecular charge transfer (TICT) character induced by inclusion complexation. The two equilibria viz. monocation{r_reversible}monocation solvent exciplex{r_reversible}neutral reported for 4ADPE in aqueous solution are not observed in presence of {beta}-CDx. The ground and excited state pK{sub a} values for monocation-neutral equilibrium of 2ADPE and 4ADPE have been reported.

  10. Removal of reactive red-120 and 4-(2-pyridylazo) resorcinol from aqueous samples by Fe{sub 3}O{sub 4} magnetic nanoparticles using ionic liquid as modifier

    Energy Technology Data Exchange (ETDEWEB)

    Absalan, Ghodratollah, E-mail: gubsulun@yahoo.com [Professor Masoumi Laboratory, Department of Chemistry, College of Science, Shiraz University, Hafeziyeh, Fars, 71454 Shiraz (Iran, Islamic Republic of); Asadi, Mozaffar; Kamran, Sedigheh; Sheikhian, Leila [Professor Masoumi Laboratory, Department of Chemistry, College of Science, Shiraz University, Hafeziyeh, Fars, 71454 Shiraz (Iran, Islamic Republic of); Goltz, Douglas M. [Department of Chemistry, University of Winnipeg, Winnipeg, MB, R3B 2E9 Canada (Canada)

    2011-08-30

    Highlights: {yields} Ionic liquids modify the dye-adsorption characteristics of magnetic nanoparticles. {yields} Modified nanoparticles improved the sensitivity of dye measurements. {yields} Water-solubility is an important factor for choosing an ionic liquid as a modifier for nanoparticles. - Abstract: The nanoparticles of Fe{sub 3}O{sub 4} as well as the binary nanoparticles of ionic liquid and Fe{sub 3}O{sub 4} (IL-Fe{sub 3}O{sub 4}) were synthesized for removal of reactive red 120 (RR-120) and 4-(2-pyridylazo) resorcinol (PAR) as model azo dyes from aqueous solutions. The mean size and the surface morphology of the nanoparticles were characterized by TEM, DLS, XRD, FTIR and TGA techniques. Adsorption of RR-120 and PAR was studied in a batch reactor at different experimental conditions such as nanoparticle dosage, dye concentration, pH of the solution, ionic strength, and contact time. Experimental results indicated that the IL-Fe{sub 3}O{sub 4} nanoparticles had removed more than 98% of both dyes under the optimum operational conditions of a dosage of 60 mg, a pH of 2.5, and a contact time of 2 min when initial dyes concentrations of 10-200 mg L{sup -1} were used. The maximum adsorption capacity of IL-Fe{sub 3}O{sub 4} was 166.67 and 49.26 mg g{sup -1} for RR-120 and PAR, respectively. The isotherm experiments revealed that the Langmuir model attained better fits to the equilibrium data than the Freundlich model. The Langmuir adsorption constants were 5.99 and 3.62 L mg{sup -1} for adsorptions of RR-120 and PAR, respectively. Both adsorption processes were endothermic and dyes could be desorbed from IL-Fe{sub 3}O{sub 4} by using a mixed NaCl-acetone solution and adsorbent was reusable.

  11. Rate Constants for the Reactions of Hydroxyl Radical with Several Alkanes, Cycloalkanes, and Dimethyl Ether

    Science.gov (United States)

    DeMore, W.; Bayes, K.

    1998-01-01

    Relative rate experiements were used to measure rate constants and temperature denpendencies of the reactions of OH with propane, n-butane, n-pentane, n-hexane, cyclopropane, cyclobutane, cyclopentane, and dimethyl ether.

  12. Acidolysis small molecular phenolic ether used as accelerator in photosensitive diazonaphthaquinone systems

    Science.gov (United States)

    Zhou, Haihua; Zou, Yingquan

    2006-03-01

    The photosensitive compounds in the photosensitive coatings of positive PS plates are the diazonaphthaquinone derivatives. Some acidolysis small molecular phenolic ethers, which were synthesized by some special polyhydroxyl phenols with vinyl ethyl ether, are added in the positive diazonaphthaquinone photosensitive composition to improve its sensitivity, composed with photo-acid-generators. The effects to the photosensitivity, anti-alkali property, anti-isopropyl alcohol property, dot resolution and line resolution of the coatings are studied with different additive percent of the special phenolic ethers. In the conventional photosensitive diazonaphthaquinone systems for positive PS plates, the photosensitivity is improved without negative effects to resolution, anti-alkali and anti-isopropyl alcohol properties when added about 5% of the special acidolysis phenolic ethers, EAAE or DPHE, composed with photo-acid-generators.

  13. Glycerol etherification with TBA: high yield to poly-ethers using a membrane assisted batch reactor.

    Science.gov (United States)

    Cannilla, Catia; Bonura, Giuseppe; Frusteri, Leone; Frusteri, Francesco

    2014-05-20

    In this work, a novel approach to obtain high yield to poly-tert-butylglycerolethers by glycerol etherification reaction with tert-butyl alcohol (TBA) is proposed. The limit of this reaction is the production of poly-ethers, which inhibits the formation of poly-ethers potentially usable in the blend with conventional diesel for transportation. The results herein reported demonstrate that the use of a water permselective membrane offers the possibility to shift the equilibrium toward the formation of poly-ethers since the water formed during reaction is continuously and selectively removed from the reaction medium by the recirculation of the gas phase. Using a proper catalyst and optimizing the reaction conditions, in a single experiment, a total glycerol conversion can be reached with a yield to poly-ethers close to 70%, which represents data never before reached using TBA as reactant. The approach here proposed could open up new opportunities for all catalytic reactions affected by water formation.

  14. Synthesis and biological evaluation of arctigenin ester and ether derivatives as activators of AMPK.

    Science.gov (United States)

    Shen, Sida; Zhuang, Jingjing; Chen, Yijia; Lei, Min; Chen, Jing; Shen, Xu; Hu, Lihong

    2013-07-01

    A series of new arctigenin and 9-deoxy-arctigenin derivatives bearing different ester and ether side chains at the phenolic hydroxyl positions are designed, synthesized, and evaluated for activating AMPK potency in L6 myoblasts. Initial biological evaluation indicates that some alkyl ester and phenethyl ether arctigenin derivatives display potential activities in AMPK phosphorylation improvement. Further structure-activity relationship analysis shows that arctigenin ester derivatives 3a, 3h and 9-deoxy-arctigenin phenethyl ether derivatives 6a, 6c, 6d activate AMPK more potently than arctigenin. Moreover, the 2-(3,4-dimethoxyphenyl)ethyl ether moiety of 6c has been demonstrated as a potential functional group to improve the effect of AMPK phosphorylation. The structural optimization of arctigenin leads to the identification of 6c as a promising lead compound that exhibits excellent activity in AMPK activation. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Degradation of the Alternaria mycotoxins alternariol, alternariol monomethyl ether, and altenuene upon bread baking.

    Science.gov (United States)

    Siegel, David; Feist, Michael; Proske, Matthias; Koch, Matthias; Nehls, Irene

    2010-09-08

    The stability of the Alternaria mycotoxins alternariol, alternariol monomethyl ether, and altenuene upon bread baking was investigated by model experiments using a spiked wholemeal wheat flour matrix. For alternariol and alternariol monomethyl ether, but not for altenuene, degradation products, formed through a sequence of hydrolysis and decarboxylation, could be identified in pilot studies. The simultaneous quantification of alternariol, alternariol monomethyl ether, altenuene, and the degradation products was achieved by a newly developed high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) multimethod. The obtained quantitative data indicate that the Alternaria mycotoxins are barely degraded during wet baking, while significant degradation occurs upon dry baking, with the stability decreasing in the order alternariol monomethyl ether>alternariol>altenuene. The novel degradation products could be detected after the wet baking of flour spiked with alternariol and in a sample survey of 24 commercial cereal based baking products.

  16. IRIS Toxicological Review of Ethylene Glycol Mono-Butyl Ether (Egbe) (External Review Draft)

    Science.gov (United States)

    EPA has conducted a peer review of the scientific basis supporting the human health hazard and dose-response assessment of ethylene glycol monobutyl ether that will appear on the Integrated Risk Information System (IRIS) database.

  17. Thermal and oxidative degradation studies of formulated C-ethers by gel-permeation chromatography

    Science.gov (United States)

    Jones, W. R., Jr.; Morales, W.

    1982-01-01

    Gel-permeation chromatography was used to analyze C-ether lubricant formulations from high-temperature bearing tests and from micro-oxidation tests. Three mu-styragel columns (one 500 and two 100 A) and a tetrahydrofuran mobile phase were found to adequately separate the C-ether degradation products. The micro-oxidation tests yielded degradation results qualitatively similar to those observed from the bearing tests. Micro-oxidation tests conducted in air yielded more degradation than did tests in nitrogen. No great differences were observed between the thermal-oxidative stabilities of the two C-ether formulations or between the catalytic degradation activities of silver and M-50 steel. C-ether formulation I did yield more degradation than did formulation II in 111- and 25-hour bearing tests, respectively.

  18. Evaluation of Efficient and Practical Methods for the Preparation of Functionalized Aliphatic Trifluoromethyl Ethers.

    Science.gov (United States)

    Sokolenko, Taras M; Dronkina, Maya I; Magnier, Emmanuel; Yagupolskii, Lev M; Yagupolskii, Yurii L

    2017-05-14

    The "chlorination/fluorination" technique for aliphatic trifluoromethyl ether synthesis was investigated and a range of products with various functional groups was prepared. The results were compared with oxidative desulfurization-fluorination of xanthates with the same structure.

  19. Ultraviolet-induced surface grafting of octafluoropentyl methacrylate on polyether ether ketone for inducing antibiofilm properties.

    Science.gov (United States)

    Amdjadi, Parisa; Nojehdehian, Hanieh; Najafi, Farhood; Ghasemi, Amir; Seifi, Massoud; Dashtimoghadam, Erfan; Fahimipour, Farahnaz; Tayebi, Lobat

    2017-07-01

    Since octafluoropentyl methacrylate is an antifouling polymer, surface modification of polyether ether ketone with octafluoropentyl methacrylate is a practical approach to obtaining anti-biofilm biocompatible devices. In the current study, the surface treatment of polyether ether ketone by the use of ultraviolet irradiation, so as to graft (octafluoropentyl methacrylate) polymer chains, was initially implemented and then investigated. The Fourier-transform infrared and nuclear magnetic resonance spectra corroborated the appearance of new signals associated with the fluoroacrylate group. Thermogravimetric curves indicated enhanced asymmetry in the polymer structure due to the introduction of the said new groups. Measuring the peak area in differential scanning calorimetry experiments also showed additional bond formation. Static water contact angle measurements indicated a change in wettability to the more hydrophobic surface. The polyether ether ketone-octafluoropentyl methacrylate surface greatly reduced the protein adsorption. This efficient method can modulate and tune the surface properties of polyether ether ketone according to specific applications.

  20. Solvent Effects on Cesium Complexation with Crown Ethers from Liquid to Supercritical Fluids

    International Nuclear Information System (INIS)

    Wai, Chien M.; Rustenholtz, Anne; Wang, Shaofen; Lee, Su-Chen; Herman, Jamie; Porter, Richard A.

    2004-01-01

    Nuclear magnetic resonance (NMR) techniques were used to study crown ether-water interactions in solvents of low dielectric constants such as chloroform and carbon tetrachloride. Water forms a 1:1 complex with a number of crown ethers including 12-crown-4, 15-crown-5, 18-crown-6, dicyclohexano-18=crown-6, dicyclohexano-24-crown 8, and dibenzl-24-crown-8 in chloroform. Among these crown ethers, the 18-crown-6-H2 complex has the largest equilibrium constant (K=545) and 97% of the crown is complexed to water in chloroform. Addition of carbon tetrachloride to chloroform lowers the equilibrium constants of the crown-water complexes. The partition coefficients of crown ethers (D=crown in water/crown in solvent) between water and organic solvent also vary with solvent composition

  1. Protective effects of ether, oxygen and their mixture for radiation in Drosophila melanogaster

    International Nuclear Information System (INIS)

    Megumi, Tsuneo; Tsujii, Yukio; Gamo, Sumiko

    1992-01-01

    Protective effects of ether mixed with air or oxygen against ionizing radiation damages were demonstrated in adult flies of Drosophila melanogaster. The protective effects against knock-down on the second day and lethality on the eighth day after irradiation were not affected by the radiation sensitivity and DNA repair capacity of the strains. Ether (4.2%) in oxygen was more effective than ether in air for both endpoints. The protective effects may be due to damages not involving cell division, since no mitotic cells are observed in adult flies except in gonadal glands. A change in the orderliness of the cell membrane by ether is suggested to be the cause of the protective effects. (author). 16 refs.; 3 tabs

  2. Modeling of a Reaction-Distillation-Recycle System to Produce Dimethyl Ether through Methanol Dehydration

    Science.gov (United States)

    Muharam, Y.; Zulkarnain, L. M.; Wirya, A. S.

    2018-03-01

    The increase in the dimethyl ether yield through methanol dehydration due to a recycle integration to a reaction-distillation system was studied in this research. A one-dimensional phenomenological model of a methanol dehydration reactor and a shortcut model of distillation columns were used to achieve the aim. Simulation results show that 10.7 moles/s of dimethyl ether is produced in a reaction-distillation system with the reactor length being 4 m, the reactor inlet pressure being 18 atm, the reactor inlet temperature being 533 K, the reactor inlet velocity being 0.408 m/s, and the distillation pressure being 8 atm. The methanol conversion is 90% and the dimethyl ether yield is 48%. The integration of the recycle stream to the system increases the dimethyl ether yield by 8%.

  3. Application of Computational Methods Mm2 and Gussian for Studing Unimolecular Decomposition of Vinil Ethers based on the Mechanism of Hydrogen Bonding

    OpenAIRE

    Behnaz Shahrokh; Garnik N. Sargsyan; Arkadi B. Harutyunyan

    2012-01-01

    Investigations of the unimolecular decomposition of vinyl ethyl ether (VEE), vinyl propyl ether (VPE) and vinyl butyl ether (VBE) have shown that activation of the molecule of a ether results in formation of a cyclic construction - the transition state (TS), which may lead to the displacement of the thermodynamic equilibrium towards the reaction products. The TS is obtained by applying energy minimization relative to the ground state of an ether under the program MM2 when...

  4. Pra Desain Pabrik Dimethyl Ether (DME dari Gas Alam

    Directory of Open Access Journals (Sweden)

    Ajeng Puspitasari Yudiputri

    2014-09-01

    Full Text Available Berdasarkan data PT Pertamina (Persero, total konsumsi LPG 2008 mencapai 1,85 juta ton dan 600.000 ton di antaranya untuk program konversi. Pada 2009 kebutuhan LPG akan meningkat menjadi 3,67 juta ton dan 2 juta ton di antaranya untuk program konversi sampai akhir tahun. Namun, sumber pasokan LPG dari dalam negeri diperkirakan tidak akan beranjak dari angka 1,8 juta ton per tahun dalam beberapa tahun mendatang. Sehingga, Indonesia harus menutup kebutuhan dengan mengimpor LPG dalam jumlah cukup besar. Maka dari itu dibutuhkan bahan bakar gas lain yang mampu mengatasi permasalahan yang ditimbulkan tersebut. Dimethyl Ether (DME merupakan senyawa ether yang paling sederhana dengan rumus kimia CH3OCH3. Produksi DME dapat dihasilkan melalui sintesis gas alam. DME berbentuk gas yang tidak berwarna pada suhu ambien, zat kimia yang stabil, dengan titik didih -25,1oC. Tekanan uap DME sekitar 0,6 Mpa pada 25oC dan dapat dicairkan seperti halnya LPG. Viskositas DME 0,12-0,15 kg/ms, setara dengan viskositas propana dan butane (konstituen utama LPG, sehingga infrastruktur untuk LPG dapat juga digunakan untuk DME. Berdasarkan data Departemen ESDM pada Januari 2012, total cadangan gas alam Indonesia tercatat mencapai 150,70 Trillion Square Cubic Feet (TSCF. Berdasarkan jumlah tersebut, sebanyak 103,35 TSCF merupakan gas alam terbukti, sementara 47,35 TSCF sisanya masih belum terbukti. Berdasarkan hal tersebut, diketahui bahwa senyawa DME merupakan senyawa yang sesuai untuk bahan substitusi LPG. Dan ditinjau dari analisa ekonomi, didapatkan besar Investasi : $ 636,447,074.69 ; Internal Rate of Return\t: 20.51%; POT: 4.13 tahun; BEP : 37.36 %; dan NPV 10 year : $ 518,848,692. Dari ketiga parameter sensitifitas yaitu fluktuasi biaya investasi, harga bahan baku, dan harga jual dari produk, terlihat bahwa ketiganya tidak memberikan pengaruh yang cukup signifikan terhadap kenaikan atau penurunan nilai IRR pabrik. Sehingga pabrik DME dari Gas Alam ini layak untuk

  5. Contact angle measurements of a polyphenyl ether to 190 C on M-50 steel

    Science.gov (United States)

    Jones, W. R., Jr.

    1981-01-01

    Contact angle measurements were performed for a polyphenyl ether on steel in nitrogen. A tilting plate and a sessile drop apparatus were used. Surface tension was measured with a maximum bubble pressure apparatus. Critical surface energies of spreading were found to be 30.1 and 31.3 dynes/cm. It was concluded that the polyphenyl ether is inherently autophobic and will not spread on its own surface film.

  6. Design and synthesis of aryl ether and sulfone hydroxamic acids as potent histone deacetylase (HDAC) inhibitors.

    Science.gov (United States)

    Pabba, Chittari; Gregg, Brian T; Kitchen, Douglas B; Chen, Zhen Jia; Judkins, Angela

    2011-01-01

    A series of novel hydroxamic acid based histone deacetylases (HDAC) inhibitors with aryl ether and aryl sulfone residues at the terminus of a substituted, unsaturated 5-carbon spacer moiety have been synthesized for the first time and evaluated. Compounds with meta- and para-substitution on the aryl ring of ether hydroxamic acids 19c, 20c, 19e, 19f and 19g are potent HDAC inhibitors with activities at low nanomolar levels. Copyright © 2010 Elsevier Ltd. All rights reserved.

  7. Influence of cellulose ether particle size on water retention of freshly-mixed mortars

    OpenAIRE

    Patural , Laetitia; Govin , Alexandre; Grosseau , Philippe; Ruot , Bertrand; Deves , Olivier

    2009-01-01

    International audience; Cellulose ethers are polymers frequently introduced into mortar formulations in order to improve water retention capacity and workability of the freshly-mixed materials. Physico-chemical parameters of these admixtures (molecular weight, granulometry, substitution degrees, etc) seem to have a strong influence on mortar water retention capacity. In this paper, the influence of cellulose ether particle size was studied. Two behaviors were highlighted regarding the particl...

  8. A new cytotoxic sterol methoxymethyl ether from a deep water marine sponge Scleritoderma sp. cf. paccardi.

    Science.gov (United States)

    Gunasekera, S P; Kelly-Borges, M; Longley, R E

    1996-02-01

    24(R)-Methyl-5 alpha-cholest-7-enyl 3 beta-methoxymethyl ether (1), a new sterol ether, has been isolated from a deep-water marine sponge Scleritoderma sp. cf. paccardi. Compound 1 exhibited in vitro cytotoxicity against the cultured murine P-388 tumor cell line with an IC50 of 2.3 micrograms/mL. The isolation and structure elucidation of 1 by NMR spectroscopy is described.

  9. The action of certain antibiotics and ether on swine enzootic pneumonia.

    Science.gov (United States)

    Huhn, R G

    1971-01-01

    The susceptibility of Mycoplasma hyopneumoniae to the action of three antibiotics and diethyl ether was determined. Infected swine were used in an in vivo sensitivity detection system. The parameter of susceptibility was lesion prophylaxis. In vivo, Mycoplasma hyopneumoniae appeared to be resistant to diethyl ether, tylosin tartrate, and erythromycin, but was susceptible to the action of chlortetracycline. Chlortetracycline was effective in preventing the development of lesions when given at levels which would be practical in commercial swine operations.

  10. Convenient procedures for the α-metallation of vinylic ethers and thioethers

    NARCIS (Netherlands)

    Verkruijsse, H.D.; Brandsma, L.; Schleyer, P. von R.

    1987-01-01

    Ethyl vinyl ether H2C=CHOC2H5 and the analogous cyclic vinylic ethers dehydrofuran and 2,3-dihydropyran can be potassiated at −20°C in the α-position with a 1/1/1 molar mixture of BuLi, t-BuOK and TMEDA in hexane. Methyl vinyl sulfide is potassiated very smoothly by a 1/1 molar mixture of BuLi and

  11. Anaerobic degradation of veratrylglycerol-beta-guaiacyl ether and guaiacoxyacetic acid by mixed rumen bacteria.

    OpenAIRE

    Chen, W; Supanwong, K; Ohmiya, K; Shimizu, S; Kawakami, H

    1985-01-01

    Veratrylglycerol-beta-guaiacyl ether (0.2 g/liter), a lignin model compound, was found to be degraded by mixed rumen bacteria in a yeast extract medium under strictly anaerobic conditions to the extent of 19% within 24 h. Guaiacoxyacetic acid, 2-(o-methoxyphenoxy)ethanol, vanillic acid, and vanillin were detected as degradation products of veratrylglycerol-beta-guaiacyl ether by thin-layer chromatography, gas chromatography, and gas chromatography-mass spectrometry. Guaiacoxyacetic acid (0.25...

  12. Process for producing high purity isoolefins and dimers thereof by dissociation of ethers

    Science.gov (United States)

    Smith, L.A. Jr.; Jones, E.M. Jr.; Hearn, D.

    1984-05-08

    Alkyl tertiary butyl ether or alkyl tertiary amyl ether is dissociated by vapor phase contact with a cation acidic exchange resin at temperatures in the range of 150 to 250 F at LHSV of 0.1 to 20 to produce a stream consisting of unreacted ether, isobutene or isoamylene and an alcohol corresponding to the alkyl radical. After the alcohol is removed, the ether/isoolefin stream may be fractionated to obtain a high purity isoolefin (99+%) or the ether/isoolefin stream can be contacted in liquid phase with a cation acidic exchange resin to selectively dimerize the isoolefin in a highly exothermic reaction, followed by fractionation of the dimerization product to produce high purity diisoolefin (97+%). In the case where the alkyl is C[sub 3] to C[sub 6] and the corresponding alcohol is produced on dissociation of the ether, combined dissociation-distillation may be carried out such that isoolefin is the overhead product and alcohol the bottom. 2 figs.

  13. Radium separation through complexation by aqueous crown ethers and ion exchange or solvent extraction

    Energy Technology Data Exchange (ETDEWEB)

    Chiarizia, R.; Dietz, M.L.; Horwitz, E.P. [Argonne National Lab., IL (United States). Chemistry Div.; Burnett, W.C. [Florida State Univ., Tallahassee, FL (United States). Dept. of Oceanography

    1997-11-01

    The effect of three water-soluble, unsubstituted crown ethers (15-crown-5 (15C5), 18-crown-6 (18C6) and 21-crown-7 (21C7)) on the uptake of Ca, Sr, Ba and Ra cations by a sulfonic acid cation exchange resin, and on the extraction of the same cations by xylene solutions of dinonylnaphthalenesulfonic acid (HDNNS) from aqueous hydrochloric acid solutions has been investigated. The crown ethers enhance the sorption of the larger cations by the ion exchange resin, thereby improving the resin selectivity over calcium, a result of a synergistic interaction between the crown ether and the ionic functional groups of the resin. Similarly, the extraction of the larger alkaline earth cations into xylene by HDNNS is strongly synergized by the presence of the crown ethers in the aqueous phase. Promising results for intra-Group IIa cation separations have been obtained using each of the three crown ethers as the aqueous ligands and the sulfonic acid cation exchange resin. Even greater separation factors for the radium-calcium couple have been measured with the crown-ethers and HDNNS solutions in the solvent extraction mode. The application of the uptake and extraction results to the development of radium separation schemes is discussed and a possible flowchart for the determination of {sup 226}Ra/{sup 228}Ra in natural waters is presented.

  14. Phthalates and polybrominated diphenyl ethers in retail stores

    Science.gov (United States)

    Xu, Ying; Liang, Yirui; Urquidi, Jorge R.; Siegel, Jeffrey A.

    2014-04-01

    Retail stores contain a wide range of products that can emit a variety of indoor pollutants. Among these chemicals, phthalate esters and polybrominated diphenyl ethers (PBDEs) are two important categories, because they are extensively used as additives in consumer products and associated with serious health concerns. This study measured six phthalate and 14 PBDE compounds inside of 12 retail stores in Texas and Pennsylvania, U.S. Phthalates and PBDEs were widely found in the retail environment, indicating that they are ubiquitous indoor air pollutants. DEP, DnBP, and DEHP were the most abundant phthalates, with DnBP showing the highest concentration (0.23 ± 0.36 μg m-3). PBDEs were dominated by BDE-28, -99, and -209, having concentrations as high as 0.85 ± 1.99 ng m-3 (BDE-99). The levels of phthalates and PBDEs measured in this study are comparable to concentrations found in previous investigations of residential buildings, with phthalates showing lower concentrations and PBDEs exhibiting higher concentrations in retail stores. The potential co-occurrence of phthalates was not as strong as that of PBDEs, suggesting that phthalates might have more diverse sources. Whole building emission rates were calculated and showed similar patterns of variations as indoor air concentrations, suggestion the diversity of indoor sources of phthalates and PBDEs in retail environments.

  15. Polybrominated diphenyl ethers in birds of prey from Northern China.

    Science.gov (United States)

    Chen, Da; Mai, Bixian; Song, Jie; Sun, Quanhui; Luo, Yong; Luo, Xiaojun; Zeng, Eddy Y; Hale, Robert C

    2007-03-15

    Birds of prey from Northern China (Beijing area) were examined for polybrominated diphenyl ethers (PBDEs). A total of 47 specimens from eight different species were analyzed. Muscle and liver were analyzed separately for each bird. Kidneys were pooled by species. Common kestrels exhibited the highest PBDE levels (mean muscle and liver concentrations of 12300 and 12200 ng/g lipid weight, respectively), with maxima in an individual bird of 31700 in muscle and 40900 ng/g lw in liver. Congener profiles differed between some species, but were generally dominated by the more brominated congeners (e.g., BDE-153, -209, -183, -207). BDE-209 was especially elevated compared to other published reports. Interspecies differences in congener concentrations and profiles may be due to diet, behavior, or biotransformation capacities. BDE-209 was detected in 79.4% of the samples. Common kestrels contained the highest BDE-209 levels (mean/maxima of 2150/6220 in muscle and 2870/12200 ng/g lw in liver). BDE-209 was the dominant congener in tissues from some buzzards, scops owls, and long-eared owls. It was the second most abundant congener in common kestrels. The remarkable levels and dominance of BDE-209 may relate to significant production, usage, or disposal of deca-containing products in China. These observations reinforce the growing view that organisms using terrestrial food chains may have greater exposure to BDE-209.

  16. Human exposure to polybrominated diphenyl ethers at production area, China.

    Science.gov (United States)

    Jin, Jun; Wang, Ying; Yang, Congqiao; Hu, Jicheng; Liu, Weizhi; Cui, Jian

    2010-05-01

    The concentrations of polybrominated diphenyl ethers (PBDEs) were detected in air and aquatic products in PBDEs production areas which are located at the south coast area of Laizhou Bay, Shandong province, China in this study. Concentrations of SigmaPBDEs in the air ranged from 0.47 ng/m3 to 161 ng/m3. In aquatic products, concentrations of SigmaPBDEs ranged from 2.7 ng/g wet weight to 42 ng/g wet weight. The mean dietary intake of SigmaPBDEs via aquatic products consumption in this study was 218 ng/day. Daily intake of SigmaPBDEs via inhalation in this study was 612 ng for men and 455 ng for women. With a contribution of 80%, BDE-209 was predominant in the total intake. Dietary intake and breathing inhalation contributed 29 and 71%, respectively, to the total PBDEs intake. The results indicate that breathing inhalation also plays a very significant pathway for the population of the PBDEs production area. Compared with similar studies in other countries, human exposure to PBDEs via diet and inhalation in this study was the highest in the world. Copyright (c) 2010 SETAC.

  17. Body burdens of polybrominated diphenyl ethers among urban anglers.

    Science.gov (United States)

    Morland, Kimberly B; Landrigan, Philip J; Sjödin, Andreas; Gobeille, Alayne K; Jones, Richard S; McGahee, Ernest E; Needham, Larry L; Patterson, Donald G

    2005-12-01

    Polybrominated diphenyl ethers (PBDEs) have been widely used in the United States and worldwide as flame retardants. Recent PBDE production figures show that worldwide use has increased. To determine whether fish consumption is a source of PBDE exposure for humans, a cross-sectional epidemiologic study of New York and New Jersey urban anglers was conducted during the summers of 2001-2003. Frequency of local fish consumption was assessed by questionnaire, and blood samples for PBDE analysis were collected from 94 anglers fishing from piers on the lower Hudson River and Newark Bay. We analyzed PBDEs by gas chromatography-isotope dilution-high-resolution mass spectrometry. The congeners found in anglers' serum at the highest concentrations were, by International Union of Pure and Applied Chemistry numbers, BDE-47, BDE-153, and BDE-99. Anglers reporting consumption of local fish had higher, but nonstatistically significantly different, concentrations of PBDEs than did anglers who did not eat local fish. For some congeners (BDE-100 and BDE-153), we observed moderate dose-response relationships between serum PBDE levels and frequency of reported fish intake. These findings suggest that consumption of locally caught fish is not a major route of human exposure for this study population.

  18. Uptake, translocation, and debromination of polybrominated diphenyl ethers in maize

    Institute of Scientific and Technical Information of China (English)

    Moming Zhao; Shuzhen Zhang; Sen Wang; Honglin Huang

    2012-01-01

    Uptake,translocation and debromination of three polybrominated diphenyl ethers(PBDEs),BDE-28,-47 and-99,in maize were studied in a hydroponic experiment.Roots took up most of the PBDEs in the culture solutions and more highly brominated PBDEs had a stronger uptake capability.PBDEs were detected in the stems and leaves of maize after exposure but rarely detected in the blank control plants.Furthermore,PBDE concentrations decreased from roots to stems and then to leaves,and a very clear decreasing gradient was found in segments upwards along the stem.These altogether provide substantiating evidence for the acropetal translocation of PBDEs in maize.More highly brominated PBDEs were translocated with more difficulty.Radial translocation of PBDEs from nodes to sheath inside maize was also observed.Both acropetal and radial translocations were enhanced at higher transpiration rates,suggesting that PBDE transport was probably driven by the transpiration stream.Debromination of PBDEs occurred in all parts of the maize,and debromination patterns of different parent PBDEs and in different parts of a plant were similar but with some differences.This study for the first time provides direct evidence for the acropetal translocation of PBDEs within plants,elucidates the process of PBDE transport and clarifies the debromination products of PBDEs in maize.

  19. Thermochemical biorefinery based on dimethyl ether as intermediate: Technoeconomic assessment

    International Nuclear Information System (INIS)

    Haro, P.; Ollero, P.; Villanueva Perales, A.L.; Gómez-Barea, A.

    2013-01-01

    Highlights: ► A thermochemical biorefinery based on bio-DME as intermediate is studied. ► The assessed concepts (12) lead to multi-product generation (polygeneration). ► In all concepts DME is converted by carbonylation or hydrocarbonylation. ► Rates of return are similar to or higher than plants producing a single product. -- Abstract: Thermochemical biorefinery based on dimethyl ether (DME) as an intermediate is studied. DME is converted into methyl acetate, which can either be hydrogenated to ethanol or sold as a co-product. Considering this option together with a variety of technologies for syngas upgrading, 12 different process concepts are analyzed. The considered products are ethanol, methyl acetate, H 2 , DME and electricity. The assessment of each alternative includes biomass pretreatment, gasification, syngas clean-up and conditioning, DME synthesis and conversion, product separation, and heat and power integration. A plant size of 500 MW th processing poplar chips is taken as a basis. The resulting energy efficiency to products ranges from 34.9% to 50.2%. The largest internal rate of return (28.74%) corresponds to a concept which produces methyl acetate, DME and electricity (exported to grid). A sensitivity analysis with respect to total plant investment (TPI), total operation costs (TOC) and market price of products was carried out. The overall conclusion is that, despite its greater complexity, this kind of thermochemical biorefinery is more profitable than thermochemical bioprocesses oriented to a single product.

  20. Crown ethers and phase transfer catalysis in polymer science

    CERN Document Server

    Carraher, Charles

    1984-01-01

    Phase transfer catalysis or interfacial catalysis is a syn­ thetic technique involving transport of an organic or inorganic salt from a solid or aqueous phase into an organic liquid where reaction with an organic-soluble substrate takes place. Over the past 15 years there has been an enormous amount of effort invested in the development of this technique in organic synthe­ sis. Several books and numerous review articles have appeared summarizing applications in which low molecular weight catalysts are employed. These generally include either crown ethers or onium salts of various kinds. While the term phase transfer catalysis is relatively new, the concept of using a phasetrans­ fer agent (PTA) is much older~ Both Schnell and Morgan employed such catalysts in synthesis of polymeric species in the early 1950's. Present developments are really extensions of these early applications. It has only been within the last several years that the use of phase transfer processes have been employed in polymer synthesis...

  1. Children's exposure to polybrominated diphenyl ethers (PBDEs) through mouthing toys.

    Science.gov (United States)

    Ionas, Alin C; Ulevicus, Jocelyn; Gómez, Ana Ballesteros; Brandsma, Sicco H; Leonards, Pim E G; van de Bor, Margot; Covaci, Adrian

    2016-02-01

    Polybrominated diphenyl ethers (PBDEs) have previously been detected in children toys, yet the risk of child exposure to these chemicals through the mouthing of toys or other items is still unknown. We aimed to expand on the current knowledge by investigating the impact of infants' mouthing activities on exposure to PBDEs present in toys. This was established by a leaching model for determining the amount PBDEs that can leach from toys into saliva in simulated conditions. The PBDE migration rate was at its highest for the 15 min low-exposure scenario incubations (198 pg/cm(2) × min) with the ERM EC-591 certified reference material (CRM) (0.17% w/w PBDEs). The leaching process was congener-dependent, since the percentage of lower brominated PBDE congeners that leached out was up to 4.5 times higher than for the heavier PBDEs. To study the scenario in which a child would mouth on a toy flame retarded with BDE 209 alone, a plastic item containing 7% BDE 209 (w/w) was also tested. The BDE 209 amounts leached out in only 15 min were higher than the amounts leached from the CRM after the 16 h incubation. For the Belgian population, the exposure scenario from mouthing on toys containing PBDEs in amounts similar to the REACH threshold was found to be lower than the exposure from mother's milk, but higher than the exposure through diet or even dust. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Sex difference in polybrominated diphenyl ether concentrations of walleyes

    Science.gov (United States)

    Madenjian, Charles P.; Trombka, Autumn W.; Rediske, Richard R.; Jude, David J.; O'Keefe, James P.

    2012-01-01

    Polybrominated diphenyl ether (PBDE) concentrations were determined for mature male and mature female walleyes (Sander vitreus) sampled from the Saginaw Bay population during 2007. PBDE concentrations in prey fish caught in the Saginaw River, the primary tributary to Saginaw Bay, and in Saginaw Bay during 2005 and 2007 also were determined. Mature male and mature female walleyes averaged 70.3 ng/g and 24.8 ng/g, respectively, in ΣPBDE, which was equal to the sum of concentrations of six PBDE congeners (BDE-28, BDE-47, BDE-99, BDE-100, BDE-153, and BDE-154). This sex difference was likely due to males spending more time in the Saginaw River system than females. Prey fish captured in the Saginaw River were roughly ten times higher in ΣPBDE than those caught in Saginaw Bay. BDE-47 was the predominant congener in both walleyes and prey fish, and this congener contributed about 50%, on average, to ΣPBDE. Congener profiles differed significantly between the two sexes of walleyes. In contrast, congener profiles of the prey fish did not differ significantly between the river-caught fish and the bay-caught fish. One plausible explanation for these congener profile results was that net trophic transfer efficiencies of PBDEs to walleyes from their prey were similar for all congeners except BDE-28, and that diet composition differed between the two sexes of walleyes.

  3. Maternal-infant transfer of polybrominated diphenyl ethers

    Energy Technology Data Exchange (ETDEWEB)

    Hirai, T.; Fujimine, Y.; Watanabe, S. [Otsuka Pharmaceutical Co., Ltd., Tokushima (Japan); Nakamura, Y. [SRL Nishinihon, Fukuoka (Japan); Shimomura, H. [Shimomura OBGY Clinic, Fukuoka (Japan); Nagayama, J. [Kyushu Univ., Fukuoka (Japan)

    2004-09-15

    Polybrominated diphenyl ethers (PBDEs) are widely used brominated flame retardants (BFRs) in plastics of automobiles, textile industry, television, personal computer, electronic appliances etc. The amount of production world-wide has reached 40,000 tons in 1992. In 1992 world-wide production of PBDEs reached 40,000 tons raising serious concern over the dangers of environmental pollution by BFRs. The toxicity of PBDEs was reported to be an antagonist of thyroid-hormone (T4) and inhibition to aryl hydrocarbon (Ah) receptor. Since PBDEs are structurally similar to PCBs and therefore they work as an antagonist. Polychlorinated biphenyl (PCBs) demonstrate biological stability and high lipophilicity. As a result, PCBs used in the past and released into the environment, have been transmitted through the food chain and accumlated in the human body over time. In Japan, approximately 58,000 tons of PCBs were produced with the grade name of Kanechlor in between 1954 and 1971. In this study, all PCB congeners and 25 PBDE congeners (17, 25, 28, 30, 32, 33, 35, 37, 47, 49, 66, 71, 75, 77, 85, 99, 100, 116, 119, 126, 138, 153, 154, 155, 166) were analyzed by the method that combines high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS). The purpose of this study was to investigate whether congener-specific PCBs and PBDEs were transferred from pregnant women to their infants.

  4. Local deformation behavior of surface porous polyether-ether-ketone.

    Science.gov (United States)

    Evans, Nathan T; Torstrick, F Brennan; Safranski, David L; Guldberg, Robert E; Gall, Ken

    2017-01-01

    Surface porous polyether-ether-ketone has the ability to maintain the tensile monotonic and cyclic strength necessary for many load bearing orthopedic applications while providing a surface that facilitates bone ingrowth; however, the relevant deformation behavior of the pore architecture in response to various loading conditions is not yet fully characterized or understood. The focus of this study was to examine the compressive and wear behavior of the surface porous architecture using micro Computed Tomography (micro CT). Pore architectures of various depths (~0.5-2.5mm) and pore sizes (212-508µm) were manufactured using a melt extrusion and porogen leaching process. Compression testing revealed that the pore architecture deforms in the typical three staged linear elastic, plastic, and densification stages characteristic of porous materials. The experimental moduli and yield strengths decreased as the porosity increased but there was no difference in properties between pore sizes. The porous architecture maintained a high degree of porosity available for bone-ingrowth at all strains. Surface porous samples showed no increase in wear rate compared to injection molded samples, with slight pore densification accompanying wear. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Biodegradation of methyl tert-butyl ether by Kocuria sp.

    Directory of Open Access Journals (Sweden)

    Kiković Dragan D.

    2012-01-01

    Full Text Available Methyl tert-butyl ether (MTBE has been used to replace the toxic compounds from gasoline and to reduce emission of air pollutants. Due to its intensive use, MTBE has become one of the most important environment pollutants. The aim of this paper is isolation and identification of the bacteria from wastewater sample of “HIP Petrohemija” Pančevo (Serbia, capable of MTBE biodegradation. The results of the investigation showed that only the bacterial isolate 27/1 was capable of growth on MTBE. The result of sequence analyzes of 16S rDNA showed that this bacterial isolate belongs to the Kocuria sp. After the incubation period of 86 days, the degradation rates of initial MTBE concentration of 25 and 125 μg/ml were 55 and 36%, respectively. These results indicated that bacteria Kocuria sp. is successfully adapted on MTBE and can be potentially used in bioremediation of soils and waters contaminated with MTBE.

  6. Chemistry and phytotoxicity of thaxtomin A alkyl ethers.

    Science.gov (United States)

    Krasnoff, Stuart B; Lobkovsky, Emil B; Wach, Michael J; Loria, Rosemary; Gibson, Donna M

    2005-11-30

    The thaxtomin phytotoxins (1 and 2) from scab-producing Streptomyces pathogens of the potato are 2,5-dioxopiperazines consisting of modified l-tryptophanyl and l-phenylalanyl units. Thaxtomin A (1) is hydroxylated at C-14, the alpha carbon of the modified l-phenylalanyl moiety. Refluxing thaxtomin A in acidified MeOH, EtOH, and i-PrOH afforded C-14 thaxtomin A methyl- (3a and 3b), ethyl- (4a and 4b), and isopropyl- (5a and 5b) ethers, respectively, in both the 11S,14R (3a, 4a, and 5a) and 11S,14S (3b, 4b, and 5b) configurations. Crystal structures were determined for 3a and 4a. Extensive NMR as well as other spectroscopic data supported structural assignments for all of the derivatives. The 11S,14R-configured derivatives were slightly less potent than the natural products (1 and 2) as inhibitors of lettuce seedling root growth, whereas the activity of the 11S,14S epimers was much reduced, indicating that the configuration at C-14 found in the naturally occurring thaxtomins is essential for biological activity. Among the 11S,14R-configured compounds, potency decreased with an increasing size of the substituted alkoxy group.

  7. Sesquiterpene amino ether and cytotoxic phenols from Dendrobium wardianum Warner.

    Science.gov (United States)

    Zhang, Cong; Liu, Shou-Jin; Yang, Liu; Yuan, Ming-Yan; Li, Jin-Yu; Hou, Bo; Li, Hong-Mei; Yang, Xing-Zhi; Ding, Chang-Chun; Hu, Jiang-Miao

    2017-10-01

    A new bibenzyl derivative, dendrocandin V (1) and a new sesquiterpene amino ether, wardianumine A (2), together with eleven known compounds, including phenanthrenes (denbinobin (3), 9,10-dihydro-denbinobin (4), mostatin (5), loddigesiinols A (6)), bibenzyls (moscatilin (7), 5-hydroxy-3,4'-dimethoxybibenzyl (8), 3,4-dihydroxy-5,4'-dimethoxy bibenzyl (9), dendrocandin A (10), gigantol (11), dendrocandin U (12)) and an alkaloids (dihydroshihunine, 13) were isolated from the EtOH extraction of stems of Dendrobium wardianum Warner. Isolation of the new compound 2 indicated that N,N-dimethylethanolamine as the key adduction in the synthesis of dendroxine and its analogs in Dendrobium species. The hypothetical biosynthetic pathway of 2 was then postulated. Inspired by literature and traditional usage of the herbal medicine, some compounds were sent for cytotoxic activity and the results indicated that compounds 1, 3, 4, 5 showed cytotoxic activities against five human cancer cell lines (HL-60, A-549, SMMC-7721, MCF-7, and SW-480) with IC50 from 2.33-38.48μM. Among those compounds, 3 and 4 showed cell line selectivity with strong activity comparable to DDP. Copyright © 2017. Published by Elsevier B.V.

  8. Amended final report on the safety assessment of PPG-40 butyl ether with an addendum to include PPG-2, -4, -5, -9, -12, -14, -15, -16, -17, -18, -20, -22, -24, -26, -30, -33, -52, and -53 butyl ethers.

    Science.gov (United States)

    Lanigan, R S

    2001-01-01

    The Polypropylene Glycol (PPG) Butyl Ethers function as skinand hair-conditioning agents in cosmetics. Intestinal absorption of the PPG Butyl Ethers was inversely proportional to the molecular weight. In general, the toxicity of the PPG Butyl Ethers decreased as the molecular weight increased. In acute studies, moderate intraperitoneal (IP) doses of various PPG Butyl Ethers caused convulsive seizures in mice and anesthetized dogs, and large oral doses caused decreased activity, anuria, renal tubular swelling and necrosis, and hepatic swelling and necrosis. PPG-2 Butyl Ether vapors were nontoxic by the inhalation route. PPG-2 Butyl Ether was nontoxic in short-term feeding and dermal exposure studies in rats. In animal irritation studies, PPG-2 Butyl Ether caused minor, transient erythema and desquamation; in addition, erythema, edema, ecchymosis, necrosis, and other changes were observed during an acute percutaneous study. PPG-2 Butyl Ether also caused minor to moderate conjunctival irritation and minor corneal injury. PPG-2 Butyl Ether when dermally applied was nontoxic to pregnant rats and was nonteratogenic at doses up to 1.0 ml/kg/day. PPG BE800 at concentrations of 0.001% to 0.26% in feed was noncarcinogenic to rats after 2 years of treatment. In clinical studies, PPG BE800 was nonirritating and nonsensitizing to the skin when tested using 200 subjects. PPG-40 Butyl Ether was neither an irritant nor a sensitizer in a repeat-insult patch test using 112 subjects. Although clinical testing did not indicate significant skin irritation is produced by these ingredients, the animal test data did indicate the potential that these ingredients can be irritating. Therefore, it was concluded that the PPG Butyl Ethers can be used safely in cosmetic products if they are formulated to avoid irritation. Data on the component ingredients, Propylene Glycol, PPG, and n-Butyl Alcohol, from previous cosmetic ingredient safety assessments were also considered and found to support

  9. Gold-catalyzed intermolecular coupling of sulfonylacetylene with allyl ethers: [3,3]- and [1,3]-rearrangements

    Directory of Open Access Journals (Sweden)

    Jungho Jun

    2013-08-01

    Full Text Available Gold-catalyzed intermolecular couplings of sulfonylacetylenes with allyl ethers are reported. A cooperative polarization of alkynes both by a gold catalyst and a sulfonyl substituent resulted in an efficient intermolecular tandem carboalkoxylation. Reactions of linear allyl ethers are consistent with the [3,3]-sigmatropic rearrangement mechanism, while those of branched allyl ethers provided [3,3]- and [1,3]-rearrangement products through the formation of a tight ion–dipole pair.

  10. Evaluation of hepatic biotransformation of polybrominated diphenyl ethers in the polar bear (Ursus maritimus).

    Science.gov (United States)

    Krieger, Lisa K; Szeitz, András; Bandiera, Stelvio M

    2016-03-01

    Polar bears are at the top of the Arctic marine food chain and are subject to exposure and bioaccumulation of environmental chemicals of concern such as polybrominated diphenyl ethers (PBDEs), which were widely used as flame retardants. The aim of the present study was to evaluate the in vitro oxidative metabolism of 2,2',4,4'-tetrabrominated diphenyl ether (BDE-47) and 2,2',4,4',5-pentabrominated diphenyl ether (BDE-99) by polar bear liver microsomes. The identification and quantification of the hydroxy-brominated diphenyl ethers formed were assessed using an ultra-high performance liquid chromatography-tandem mass spectrometry-based method. Incubation of BDE-47 with archived individual liver microsomes, prepared from fifteen polar bears from northern Canada, produced a total of eleven hydroxylated metabolites, eight of which were identified using authentic standards. The major metabolites were 4'-hydroxy-2,2',4,5'-tetrabromodiphenyl ether and 5'-hydroxy-2,2',4,4'-tetrabromodiphenyl ether. Incubation of BDE-99 with polar bear liver microsomes produced a total of eleven hydroxylated metabolites, seven of which were identified using authentic standards. The major metabolites were 2,4,5-tribromophenol and 4-hydroxy-2,2',3,4',5-pentabromodiphenyl ether. Among the CYP specific antibodies tested, anti-rat CYP2B was found to be the most active in inhibiting the formation of hydroxylated metabolites of both BDE-47 and BDE-99, indicating that CYP2B was the major CYP enzyme involved in the oxidative biotransformation of these two congeners. Our study shows that polar bears are capable of forming multiple hydroxylated metabolites of BDE-47 and BDE-99 in vitro and demonstrates the role of CYP2B in the biotransformation and possibly in the toxicity of BDE-47 and BDE-99 in polar bears. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Metal ion separations with proton-ionizable Lariat Ethers and their polymers

    International Nuclear Information System (INIS)

    Bartsch, R.A.

    1993-01-01

    The preparation of novel and specific organic complexing agents may lead to the development of new separation systems for aqueous metal ions. Thus the introduction of highly lipophilic oximes led to the current utilization of these compounds as commercial extractants for the hydrometallurgy of nonferrous metals. Crown ethers (macrocyclic polyethers) have been employed in the laboratory-scale solvent extraction of alkali-metal, alkaline-earth, and other metal cations into organic phases. Attachment of side arms to crown ethers gives lariat ethers. The presence of one or more potential coordination sites in the side arm of the lariat ether may produce substantial changes in the selectivity and efficiency of metal ion complexation. It has been demonstrated that concomitant transfer of an aqueous phase anion into the organic medium is not required for metal ion extraction. This factor is of immense importance to potential practical applications of these proton-ionizable crown ethers in which the common, hard, aqueous phase anions would be involved. Another advantage of proton-ionizable lariat ethers is the ease with which extracted metal ions may be stripped from the organic phase by shaking with aqueous mineral acid. Thus both metal ion extraction and stripping are facilitated by pendent proton-ionizable groups. Most of the hazardous metal ion species in the Hanford Site tank wastes are members of the alkali-metal, alkaline-earth, lanthanide, and actinide families. These hard metal ion species prefer association with hard donor atoms, such as oxygens. Therefore, crown and lariat ethers are well-suited for complexation with such metal ion species

  12. Effects of ethylene glycol ethers on diesel fuel properties and emissions in a diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Cuenca, F.; Gomez-Marin, M. [Compania Logistica de Hidrocarburos (CLH), Central Laboratory, Mendez Alvaro 44, 28045 Madrid (Spain); Folgueras-Diaz, M.B., E-mail: belenfd@uniovi.es [Department of Energy, University of Oviedo, Independencia 13, 33004 Oviedo (Spain)

    2011-08-15

    Highlights: {yields} Effect of ethylene glycol ethers on diesel fuel properties. {yields} Effect of ethylene glycol ethers on diesel engine specific consumption and emissions. {yields} Blends with {<=}4 wt.% of oxygen do not change substantially diesel fuel quality. {yields} Blends with 1 and 2.5 wt.% of oxygen reduce CO and HC emissions, but not smoke. - Abstract: The effect of ethylene glycol ethers on both the diesel fuel characteristics and the exhaust emissions (CO, NO{sub x}, smoke and hydrocarbons) from a diesel engine was studied. The ethers used were monoethylene glycol ethyl ether (EGEE), monoethylene glycol butyl ether (EGBE), diethylene glycol ethyl ether (DEGEE). The above effect was studied in two forms: first by determining the modification of base diesel fuel properties by using blends with oxygen concentration around 4 wt.%, and second by determining the emission reductions for blends with low oxygen content (1 wt.%) and with 2.5 wt.% of oxygen content. The addition of DEGEE enhances base diesel fuel cetane number, but EGEE and EGBE decrease it. For concentrations of {>=}4 wt.% of oxygen, EGEE and diesel fuel can show immiscibility problems at low temperatures ({<=}0 {sup o}C). Also, every oxygenated compound, according to its boiling point, modifies the distillation curve at low temperatures and the distillate percentage increases. These compounds have a positive effect on diesel fuel lubricity, and slightly decrease its viscosity. Blends with 1 and 2.5 wt.% oxygen concentrations were used in order to determine their influence on emissions at both full and medium loads and different engine speeds. Generally, all compounds help to reduce CO, and hydrocarbon emissions, but not smoke. The best results were obtained for blends with 2.5 wt.% of oxygen. At this concentration, the additive efficiency in decreasing order was EGEE > DEGEE > EGBE for CO emissions and DGEE > EGEE > EGBE for hydrocarbon emissions. For NO{sub x}, both its behaviour and the

  13. DIMETHYL ETHER (DME)-FUELED SHUTTLE BUS DEMONSTRATION PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    Elana M. Chapman; Shirish Bhide; Jennifer Stefanik; Howard Glunt; Andre L. Boehman; Allen Homan; David Klinikowski

    2003-04-01

    The objectives of this research and demonstration program are to convert a campus shuttle bus to operation on dimethyl ether, a potential ultra-clean alternative diesel fuel. To accomplish this objective, this project includes laboratory evaluation of a fuel conversion strategy, as well as, field demonstration of the DME-fueled shuttle bus. Since DME is a fuel with no lubricity (i.e., it does not possess the lubricating quality of diesel fuel), conventional fuel delivery and fuel injection systems are not compatible with dimethyl ether. Therefore, to operate a diesel engine on DME one must develop a fuel-tolerant injection system, or find a way to provide the necessary lubricity to the DME. In this project, they have chosen the latter strategy in order to achieve the objective with minimal need to modify the engine. Their strategy is to blend DME with diesel fuel, to obtain the necessary lubricity to protect the fuel injection system and to achieve low emissions. The bulk of the efforts over the past year were focused on the conversion of the campus shuttle bus. This process, started in August 2001, took until April 2002 to complete. The process culminated in an event to celebrate the launching of the shuttle bus on DME-diesel operation on April 19, 2002. The design of the system on the shuttle bus was patterned after the system developed in the engine laboratory, but also was subjected to a rigorous failure modes effects analysis (FMEA, referred to by Air Products as a ''HAZOP'' analysis) with help from Dr. James Hansel of Air Products. The result of this FMEA was the addition of layers of redundancy and over-pressure protection to the system on the shuttle bus. The system became operational in February 2002. Preliminary emissions tests and basic operation of the shuttle bus took place at the Pennsylvania Transportation Institute's test track facility near the University Park airport. After modification and optimization of the system on

  14. Effect of polybrominated diphenyl ether congeners on placental cytokine production.

    Science.gov (United States)

    Arita, Yuko; Yeh, Corinne; Thoma, Theodosia; Getahun, Darios; Menon, Ramkumar; Peltier, Morgan R

    2018-02-01

    Polybrominated diphenyl ethers (PBDEs) are pollutants that may increase the risk of preterm birth. In previous studies, we found that a mixture of PBDEs altered the expression of biomarkers for preterm birth by the placenta. However, there are 209 different PBDE congeners with different tissue distributions. How these different congeners may alter the production of immunomodulators by the placenta that help to maintain the survival of the fetal allograft is unclear. Therefore, we compared the effects 5 common congeners on basal and bacteria-stimulated cytokine production by the placenta. Placental explant cultures were incubated with 20 μM of PBDE congeners 47, 99, 100, 153, 209 or vehicle in the presence and absence of Escherichia coli for 20 h. Conditioned medium was harvested and concentrations of IL-1β, TNF-α, IL-6, sgp130, HO-1, IL-10, BDNF, and 8-IsoP quantified. For unstimulated cultures, all congeners, except for PBDE-47, reduced the production of IL-1β and IL-6 production was enhanced by PBDE-153. BDNF concentrations tended to be reduced by most PBDE congeners and IL-10 production was enhanced by PBDE-99, -153, and -209. 8-IsoP production was enhanced by PBDE-153, but not the other congeners. For bacteria-stimulated cultures, PBDE-47 increased IL-1β production and PBDE-47, -153, and -209 tended to reduce TNF-α production. IL-6 production was enhanced by all PBDEs except 153. IL-10 production was enhanced by all congeners except for PBDE-47. All congeners significantly enhanced BDNF and 8-IsoP. These results suggest that PBDEs can alter the expression of placental biomarkers in a congener and infection-dependent manner. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Autoignited lifted flames of dimethyl ether in heated coflow air

    KAUST Repository

    Al-Noman, Saeed M.

    2018-05-16

    Autoignited lifted flames of dimethyl ether (DME) in laminar nonpremixed jets with high-temperature coflow air have been studied experimentally. When the initial temperature was elevated to over 860 K, an autoignition occurred without requiring an external ignition source. A planar laser-induced fluorescence (PLIF) technique for formaldehyde (CH2O) visualized qualitatively the zone of low temperature kinetics in a premixed flame. Two flame configurations were investigated; (1) autoignited lifted flames with tribrachial edge having three distinct branches of a lean and a rich premixed flame wings with a trailing diffusion flame and (2) autoignited lifted flames with mild combustion when the fuel was highly diluted. For the autoignited tribrachial edge flames at critical autoignition conditions, exhibiting repetitive extinction and re-ignition phenomena near a blowout condition, the characteristic flow time (liftoff height scaled with jet velocity) was correlated with the square of the ignition delay time of the stoichiometric mixture. The liftoff heights were also correlated as a function of jet velocity times the square of ignition delay time. Formaldehydes were observed between the fuel nozzle and the lifted flame edge, emphasizing a low-temperature kinetics for autoignited lifted flames, while for a non-autoignited lifted flame, formaldehydes were observed near a thin luminous flame zone.For the autoignited lifted flames with mild combustion, especially at a high temperature, a unique non-monotonic liftoff height behavior was observed; decreasing and then increasing liftoff height with jet velocity. This behavior was similar to the binary mixture fuels of CH4/H2 and CO/H2 observed previously. A transient homogeneous autoignition analysis suggested that such decreasing behavior with jet velocity can be attributed to partial oxidation characteristics of DME in producing appreciable amounts of CH4/CO/H2 ahead of the edge flame region.

  16. Dose- and time-dependent pharmacokinetics of apigenin trimethyl ether.

    Science.gov (United States)

    Elhennawy, Mai Gamal; Lin, Hai-Shu

    2018-06-15

    Apigenin trimethyl ether (5,7,4'-trimethoxyflavone, ATE), one of the key polymethoxyflavones present in black ginger (rhizome of Kaempferia parviflora) possesses various health-promoting activities. To optimize its medicinal application, the pharmacokinetics of ATE was assessed in Sprague-Dawley rats with emphases to identify the impacts from dose and repeated dosing on its major pharmacokinetic parameters. Plasma ATE levels were monitored by liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Upon single intravenous administration (2 mg/kg), plasma levels of ATE declined through an apparent first-order process while dose-escalation to 4 and 8 mg/kg led to its non-linear disposition, which could be described by the Michaelis-Menten model. Similarly, dose-dependent oral pharmacokinetics was confirmed and when the dose was escalated from 5 to 15 and 45 mg/kg, much longer mean residence time (MRT 0→last ), higher dose-normalized maximal plasma concentration (C max /Dose) and exposure (AUC/Dose) were observed at 15 and/or 45 mg/kg. One-week daily oral administration of ATE at 15 mg/kg caused its accelerated elimination and the plasma exposure (AUC) after intravenous (2 mg/kg) and oral administration (15 mg/kg) dropped ~40 and 60%, respectively. As ATE displayed both dose- and time-dependent pharmacokinetics, caution is needed in the medicinal applications of ATE and/or black ginger. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Microbial electricity generation enhances decabromodiphenyl ether (BDE-209 degradation.

    Directory of Open Access Journals (Sweden)

    Yonggang Yang

    Full Text Available Due to environmental persistence and biotoxicity of polybrominated diphenyl ethers (PBDEs, it is urgent to develop potential technologies to remediate PBDEs. Introducing electrodes for microbial electricity generation to stimulate the anaerobic degradation of organic pollutants is highly promising for bioremediation. However, it is still not clear whether the degradation of PBDEs could be promoted by this strategy. In this study, we hypothesized that the degradation of PBDEs (e.g., BDE-209 would be enhanced under microbial electricity generation condition. The functional compositions and structures of microbial communities in closed-circuit microbial fuel cell (c-MFC and open-circuit microbial fuel cell (o-MFC systems for BDE-209 degradation were detected by a comprehensive functional gene array, GeoChip 4.0, and linked with PBDE degradations. The results indicated that distinctly different microbial community structures were formed between c-MFCs and o-MFCs, and that lower concentrations of BDE-209 and the resulting lower brominated PBDE products were detected in c-MFCs after 70-day performance. The diversity and abundance of a variety of functional genes in c-MFCs were significantly higher than those in o-MFCs. Most genes involved in chlorinated solvent reductive dechlorination, hydroxylation, methoxylation and aromatic hydrocarbon degradation were highly enriched in c-MFCs and significantly positively correlated with the removal of PBDEs. Various other microbial functional genes for carbon, nitrogen, phosphorus and sulfur cycling, as well as energy transformation process, were also significantly increased in c-MFCs. Together, these results suggest that PBDE degradation could be enhanced by introducing the electrodes for microbial electricity generation and by specifically stimulating microbial functional genes.

  18. Carcinogenicity of methyl-tertiary butyl ether in gasoline.

    Science.gov (United States)

    Mehlman, Myron A

    2002-12-01

    Methyl tertiary butyl ether (MTBE) was added to gasoline on a nationwide scale in 1992 without prior testing of adverse, toxic, or carcinogenic effects. Since that time, numerous reports have appeared describing adverse health effects of individuals exposed to MTBE, both from inhalation of fumes in the workplace and while pumping gasoline. Leakage of MTBE, a highly water-soluble compound, from underground storage tanks has led to contamination of the water supply in many areas of the United States. Legislation has been passed by many states to prohibit the addition of MTBE to gasoline. The addition of MTBE to gasoline has not accomplished its stated goal of decreasing air pollution, and it has posed serious health risks to a large portion of the population, particularly the elderly and those with respiratory problems, asthma, and skin sensitivity. Reports of animal studies of carcinogenicity of MTBE began to appear in the 1990s, prior to the widespread introduction of MTBE into gasoline. These reports were largely ignored. In ensuing years, further studies have shown that MTBE causes various types of malignant tumors in mice and rats. The National Toxicology Program (NTP) Board of Scientific Counselors' Report on Carcinogens Subcommittee met in December 1998 to consider listing MTBE as "reasonably anticipated to be a human carcinogen." In spite of recommendations from Dr. Bailer, the primary reviewer, and other scientists on the committee, the motion to list MTBE in the report was defeated by a six to five vote, with one abstention. On the basis of animal studies, it is widely accepted that if a chemical is carcinogenic in appropriate laboratory animal test systems, it must be treated as though it were carcinogenic in humans. In the face of compelling evidence, NTP Committee members who voted not to list MTBE as "reasonably anticipated to be a human carcinogen" did a disservice to the general public; this action may cause needless exposure of many to health risks

  19. Depositional characteristics of atmospheric polybrominated diphenyl ethers on tree barks

    Directory of Open Access Journals (Sweden)

    Man Young Chun

    2014-07-01

    Full Text Available Objectives This study was conducted to determine the depositional characteristics of several tree barks, including Ginkgo (Ginkgo biloba, Pine (Pinus densiflora, Platanus (Platanus, and Metasequoia (Metasequoia glyptostroboides. These were used as passive air sampler (PAS of atmospheric polybrominated diphenyl ethers (PBDEs. Methods Tree barks were sampled from the same site. PBDEs were analyzed by highresolution gas chromatography/high-resolution mass spectrometer, and the lipid content was measured using the gravimetric method by n-hexane extraction. Results Gingko contained the highest lipid content (7.82 mg/g dry, whereas pine (4.85 mg/g dry, Platanus (3.61 mg/g dry, and Metasequoia (0.97 mg/g dry had relatively lower content. The highest total PBDEs concentration was observed in Metasequoia (83,159.0 pg/g dry, followed by Ginkgo (53,538.4 pg/g dry, Pine (20,266.4 pg/g dry, and Platanus (12,572.0 pg/g dry. There were poor correlations between lipid content and total PBDE concentrations in tree barks (R2=0.1011, p =0.682. Among the PBDE congeners, BDE 206, 207 and 209 were highly brominated PBDEs that are sorbed to particulates in ambient air, which accounted for 90.5% (84.3-95.6% of the concentration and were therefore identified as the main PBDE congener. The concentrations of particulate PBDEs deposited on tree barks were dependent on morphological characteristics such as surface area or roughness of barks. Conclusions Therefore, when using the tree barks as the PAS of the atmospheric PBDEs, samples belonging to same tree species should be collected to reduce errors and to obtain reliable data.

  20. Depositional characteristics of atmospheric polybrominated diphenyl ethers on tree barks.

    Science.gov (United States)

    Chun, Man Young

    2014-07-17

    This study was conducted to determine the depositional characteristics of several tree barks, including Ginkgo (Ginkgo biloba), Pine (Pinus densiflora), Platanus (Platanus), and Metasequoia (Metasequoia glyptostroboides). These were used as passive air sampler (PAS) of atmospheric polybrominated diphenyl ethers (PBDEs). Tree barks were sampled from the same site. PBDEs were analyzed by highresolution gas chromatography/high-resolution mass spectrometer, and the lipid content was measured using the gravimetric method by n-hexane extraction. Gingko contained the highest lipid content (7.82 mg/g dry), whereas pine (4.85 mg/g dry), Platanus (3.61 mg/g dry), and Metasequoia (0.97 mg/g dry) had relatively lower content. The highest total PBDEs concentration was observed in Metasequoia (83,159.0 pg/g dry), followed by Ginkgo (53,538.4 pg/g dry), Pine (20,266.4 pg/g dry), and Platanus (12,572.0 pg/g dry). There were poor correlations between lipid content and total PBDE concentrations in tree barks (R(2)=0.1011, p =0.682). Among the PBDE congeners, BDE 206, 207 and 209 were highly brominated PBDEs that are sorbed to particulates in ambient air, which accounted for 90.5% (84.3-95.6%) of the concentration and were therefore identified as the main PBDE congener. The concentrations of particulate PBDEs deposited on tree barks were dependent on morphological characteristics such as surface area or roughness of barks. Therefore, when using the tree barks as the PAS of the atmospheric PBDEs, samples belonging to same tree species should be collected to reduce errors and to obtain reliable data.

  1. Synthesis and physicochemical properties of polyhydroxylated diphenyl ethers

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Fu; Zhang, Xuesheng; Qu, Ruijuan; Shi, Jiaqi; Wang, Zunyao, E-mail: wangzun315cn@163.com

    2013-09-20

    Highlights: • The experimental pK{sub a1} values of five synthesized PHODEs were determined. • The hydrogen bonds existed in PHODEs were investigated. • There exist close relationships between the thermodynamic properties and N{sub PHOS}. • The relative stability order of PHODE congeners was theoretically proposed. - Abstract: Five polyhydroxylated diphenyl ethers (PHODEs) were synthesized. The first ionization constants (pK{sub a1}) of the synthesized compounds and seven phenolic compounds were determined using potentiometric titration experiments, together with the software ACD/Labs pK{sub a} DB program (version 6.0). The compared results showed that the software could be used to predict the pK{sub a1} of all 209 PHODEs. The thermodynamic properties of 209 PHODEs were calculated using density functional theory (DFT) at the B3LYP/6-311G** level with Gaussian 09 program. The standard enthalpy of formation (Δ{sub f}H{sup θ}) and the standard Gibbs energy of formation (Δ{sub f}G{sup θ}) were obtained. Two types of hydrogen bond were found to exist in the PHODEs’ molecules. The intramolecular hydrogen bond energies were discussed. The relative stability of PHODEs isomers was proposed theoretically with the relative standard Gibbs energy of formation (Δ{sub f}G{sub R}{sup θ}). The relationships of S{sup θ}, Δ{sub f}H{sup θ} and Δ{sub f}G{sup θ} to the number and position of the hydroxyl substitution (N{sub PHOS}) were studied.

  2. Phospholipid ether analogs for the detection of colorectal tumors.

    Directory of Open Access Journals (Sweden)

    Dustin A Deming

    Full Text Available The treatment of localized colorectal cancer (CRC depends on resection of the primary tumor with adequate margins and sufficient lymph node sampling. A novel imaging agent that accumulates in CRCs and the associated lymph nodes is needed. Cellectar Biosciences has developed a phospholipid ether analog platform that is both diagnostic and therapeutic. CLR1502 is a near-infrared fluorescent molecule, whereas 124/131I-CLR1404 is under clinical investigation as a PET tracer/therapeutic agent imaged by SPECT. We investigated the use of CLR1502 for the detection of intestinal cancers in a murine model and 131I-CLR1404 in a patient with metastatic CRC. Mice that develop multiple intestinal tumors ranging from adenomas to locally advanced adenocarcinomas were utilized. After 96 hours post CLR1502 injection, the intestinal tumors were analyzed using a Spectrum IVIS (Perkin Elmer and a Fluobeam (Fluoptics. The intensity of the fluorescent signal was correlated with the histological characteristics for each tumor. Colon adenocarcinomas demonstrated increased accumulation of CLR1502 compared to non-invasive lesions (total radiant efficiency: 1.76×10(10 vs 3.27×10(9 respectively, p = 0.006. Metastatic mesenteric tumors and uninvolved lymph nodes were detected with CLR1502. In addition, SPECT imaging with 131I-CLR1404 was performed as part of a clinical trial in patients with advanced solid tumors. 131I-CLR1404 was shown to accumulate in metastatic tumors in a patient with colorectal adenocarcinoma. Together, these compounds might enhance our ability to properly resect CRCs through better localization of the primary tumor and improved lymph node identification as well as detect distant disease.

  3. Autoignited lifted flames of dimethyl ether in heated coflow air

    KAUST Repository

    Al-Noman, Saeed M.; Choi, Byung Chul; Chung, Suk-Ho

    2018-01-01

    Autoignited lifted flames of dimethyl ether (DME) in laminar nonpremixed jets with high-temperature coflow air have been studied experimentally. When the initial temperature was elevated to over 860 K, an autoignition occurred without requiring an external ignition source. A planar laser-induced fluorescence (PLIF) technique for formaldehyde (CH2O) visualized qualitatively the zone of low temperature kinetics in a premixed flame. Two flame configurations were investigated; (1) autoignited lifted flames with tribrachial edge having three distinct branches of a lean and a rich premixed flame wings with a trailing diffusion flame and (2) autoignited lifted flames with mild combustion when the fuel was highly diluted. For the autoignited tribrachial edge flames at critical autoignition conditions, exhibiting repetitive extinction and re-ignition phenomena near a blowout condition, the characteristic flow time (liftoff height scaled with jet velocity) was correlated with the square of the ignition delay time of the stoichiometric mixture. The liftoff heights were also correlated as a function of jet velocity times the square of ignition delay time. Formaldehydes were observed between the fuel nozzle and the lifted flame edge, emphasizing a low-temperature kinetics for autoignited lifted flames, while for a non-autoignited lifted flame, formaldehydes were observed near a thin luminous flame zone.For the autoignited lifted flames with mild combustion, especially at a high temperature, a unique non-monotonic liftoff height behavior was observed; decreasing and then increasing liftoff height with jet velocity. This behavior was similar to the binary mixture fuels of CH4/H2 and CO/H2 observed previously. A transient homogeneous autoignition analysis suggested that such decreasing behavior with jet velocity can be attributed to partial oxidation characteristics of DME in producing appreciable amounts of CH4/CO/H2 ahead of the edge flame region.

  4. Development of an EtherCAT enabled digital servo controller for the Green Bank Telescope

    Science.gov (United States)

    Whiteis, Peter G.; Mello, Melinda J.

    2012-09-01

    EtherCAT (Ethernet for Control Automation Technology) is gaining wide spread popularity in the automation industry as a real time field bus based on low cost, Ethernet hardware. EtherCAT maximizes use of 100Mbps Ethernet hardware by using a collision free ring topology, efficient Ethernet frame utilization (> 95%), and data exchange "on the fly". These characteristics enable EtherCAT to achieve Master to Slave node data exchange rates of > 1000 Hz. The Green Bank Telescope, commissioned in 2000, utilizes an analog control system for motion control of 8 elevation and 16 azimuth motors. This architecture, while sufficient for observations at frequencies up to 50GHz, has significant limitations for the current scientific goals of observing at 115GHz. Accordingly, the Green Bank staff has embarked on a servo upgrade project to develop a digital servo system which accommodates development and implementation of advanced control algorithms. This paper describes how the new control system requirements, use of existing infrastructure and budget constraints led us to define a distributed motion control architecture where EtherCAT real-time Ethernet was selected as the communication bus. Finally, design details are provided that describe how NRAO developed a custom EtherCAT-enabled motor controller interface for the GBT's legacy motor drives in order to provide technical benefits and flexibility not available in commercial products.

  5. Planck's constant and the three waves (TWs) of Einstein's covariant ether

    Science.gov (United States)

    Kostro, L.

    1985-11-01

    The implications of a three-wave model for elementary particles, satisfying the principles of both quantum mechanics and General Relativity (GR), are discussed. In GR, the ether is the fundamental source of all activity, where particles (waves) arise at singularities. Inertia and gravity are field properties of the ether. In flat regions of the space-time geodesic, wave excitations correspond to the presence of particles. A momentum-carrying excitation which occurs in the ether is a superluminal radiation (phase- or B-waves) which transports neither energy nor mass. Superposition of the B-waves produces soliton-like excitations on the ether to form C-waves, i.e., particles. The particle-waves travel through space-time on D-waves, and experience reflection, refraction and interference only where B-waves have interacted with the ether. The original particles, photons-maximons, existed at the Big Bang and had physical properties which are describable in terms of Planck's quantities.

  6. Synthesis of Novel Ether Thionocarbamates and Study on Their Flotation Performance for Chalcopyrite

    Directory of Open Access Journals (Sweden)

    Gang Zhao

    2016-09-01

    Full Text Available Novel ether thionocarbamates, O-butoxy isopropyl-N-ethoxycarbonyl thionocarbamate (BIPECTC and O-(2-butoxy-1-methylethoxy isopropyl-N-ethoxycarbonyl thionocarbamate (BMIPECTC, were synthesized in this study. Their collecting efficiencies in the flotation of chalcopyrite were investigated using flotation tests, adsorption measurements, ultraviolet spectra (UV and Fourier transform-infrared spectroscopy (FT-IR and density functional theory (DFT calculations. The synthesized ether thionocarbamates showed better frothing properties than methyl-isobutyl-carbinol (MIBC and stronger affinity to chalcopyrite compared with O-isopropyl-N-ethyl thionocarbamate (IPETC and O-isobutyl-N-ethoxycarbonyl thionocarbamate (IBECTC. UV spectra analysis showed that the ether thionocarbamates react with Cu2+, with the exception of Fe2+, Ni2+, Zn2+ and Pb2+. Additionally, it was further confirmed by FTIR spectra that a chemical reaction occurs between copper ion and BIPECTC and BMIPECTC. The adsorption capacity measurements revealed that chalcopyrite exhibits good adsorption ability for ether thionocarbamates at an approximate pH of 8–10, which agrees with the flotation tests. The quantum chemistry calculation results indicated that the ether thionocarbamates exhibit stronger collecting ability for copper mineral in terms of frontier molecular orbital analysis, binding model simulation with copper ions and the molecular hydrophobicity compared with IPETC and IBECTC. The computational results are in very good agreement with the experimental results.

  7. Metabolism of nitrodiphenyl ether herbicides by dioxin-degrading bacterium Sphingomonas wittichii RW1.

    Science.gov (United States)

    Keum, Young Soo; Lee, Young Ju; Kim, Jeong-Han

    2008-10-08

    Nitrodiphenyl ether herbicides, including chlomethoxyfen, nitrofen, and oxyfluorfen are potent herbicides. Some metabolites and parent compounds are considered as possible mutagens and endocrine disruptors. Both properties pose serious hygienic and environmental risks. Sphingomonas wittichii RW1 is a well-known degrader of polychlorinated dibenzo- p-dioxins, dibenzofurans, and diphenyl ethers. However, no detailed research of its metabolic activity has been performed against pesticides with a diphenyl ether scaffold. In this study, we report S. wittichii RW1 as a very potent diphenyl ether herbicide-metabolizing bacterium with broad substrate specificity. The structures of metabolites were determined by instrumental analysis and synthetic standards. Most pesticides were rapidly removed from the culture medium in the order of nitrofen > oxyfluorfen > chlomethoxyfen. In general, herbicides were degraded through the initial reduction and N-acetylation of nitro groups, followed by ether bond cleavage. Relatively low concentrations of phenolic and catecholic metabolites throughout the study suggested that these metabolites were rapidly metabolized and incorporated into primary metabolism. These results indicate that strain RW1 has very versatile metabolic activities over a wide range of environmental contaminants.

  8. Polybrominated diphenyl ethers: human tissue levels and toxicology.

    Science.gov (United States)

    Gill, Udai; Chu, Ih; Ryan, John J; Feeley, Mark

    2004-01-01

    PBDEs are being released to the environment in wastes from their production facilities, degradation, or leaching and volatilization from products that contain PBDEs during the product's useful life. Brominated diphenyl ether congeners BDE-47, -99, and -153 are ubiquitous in the environment and are regarded as the most dominant congeners present in wildlife and humans. The tetra- to hexa-BDE are most likely the congeners to which humans are exposed through food consumption. Knowledge of PBDE uptake, metabolism, elimination, and enzyme induction is restricted largely to rodents (rats and mice) in vitro and in vivo. Feeding studies have shown that excretion of higher brominated BDEs is much greater than lower brominated BDEs. Penta-BDE is more toxic than octa- and deca-BDE following oral administration (oral LD50 in rats, 0.5-5 g/kg). In rodents, repeated exposure to PBDEs results in thyroid hormone disruption, developmental neurotoxicity, some changes of fetal development, and hepatotoxic effects. The observed chronic NOELs depend upon the technical mixture type (i.e., deca-, octa-, or penta- and their congener composition), animal species, and study protocol. Values range from 0.6 to 100 mg/kg in rats and from I to 100 mg/kg in mice. PBDEs are neither mutagenic nor genotoxic. Immunotoxicity in mice is observed following exposure to BDE-47 at 18 mg/kg/d, where splenocyte number decreased. Mice exposed neonatally to a single oral dose of BDE-47(10.5 mg/kg) or BDE-99 (12 mg/kg) on Pnd10 (period of rapid brain growth and development) show permanent impairment of spontaneous motor behavior when reaching adulthood. BDE-99 also induced adverse effects on learning and memory functions of mice. The estimated daily intake based on food consumption for PBDEs ranges from 44 to 51 ng/d, with fish contributing almost one-half. The BDE-99 body burden from a human milk survey can be estimated at 0.64 microg/kg, well below the experimental body burden of 0.4 mg/kg BDE-99 associated

  9. DIMETHYL ETHER (DME)-FUELED SHUTTLE BUS DEMONSTRATION PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    Elana M. Chapman; Shirish Bhide; Jennifer Stefanik; Howard Glunt; Andre L. Boehman; Allen Homan; David Klinikowski

    2003-04-01

    The objectives of this research and demonstration program are to convert a campus shuttle bus to operation on dimethyl ether, a potential ultra-clean alternative diesel fuel. To accomplish this objective, this project includes laboratory evaluation of a fuel conversion strategy, as well as, field demonstration of the DME-fueled shuttle bus. Since DME is a fuel with no lubricity (i.e., it does not possess the lubricating quality of diesel fuel), conventional fuel delivery and fuel injection systems are not compatible with dimethylether. Therefore, to operate a diesel engine on DME one must develop a fuel-tolerant injection system, or find a way to provide the necessary lubricity to the DME. In this project, they have chosen the latter strategy in order to achieve the objective with minimal need to modify the engine. The strategy is to blend DME with diesel fuel, to obtain the necessary lubricity to protect the fuel injection system and to achieve low emissions. The bulk of the efforts over the past year were focused on the conversion of the campus shuttle bus. This process, started in August 2001, took until April 2002 to complete. The process culminated in an event to celebrate the launching of the shuttle bus on DME-diesel operation on April 19, 2002. The design of the system on the shuttle bus was patterned after the system developed in the engine laboratory, but also was subjected to a rigorous failure modes effects analysis with help from Dr. James Hansel of Air Products. The result of this FMEA was the addition of layers of redundancy and over-pressure protection to the system on the shuttle bus. The system became operation in February 2002. Preliminary emissions tests and basic operation of the shuttle bus took place at the Pennsylvania Transportation institute's test track facility near the University Park airport. After modification and optimization of the system on the bus, operation on the campus shuttle route began in early June 2002. However, the

  10. Ethyl tertiary-butyl ether: a toxicological review.

    Science.gov (United States)

    McGregor, Douglas

    2007-05-01

    A number of oxygenated compounds (oxygenates) are available for use in gasoline to reduce vehicle exhaust emissions, reduce the aromatic compound content, and avoid the use of organo-lead compounds, while maintaining high octane numbers. Ethyl tertiary-butyl ether (ETBE) is one such compound. The current use of ETBE in gasoline or petrol is modest but increasing, with consequently similar trends in the potential for human exposure. Inhalation is the most likely mode of exposure, with about 30% of inhaled ETBE being retained by the lungs and distributed around the body. Following cessation of exposure, the blood concentration of ETBE falls rapidly, largely as a result of its metabolism to tertiary-butyl alcohol (TBA) and acetaldehyde. TBA may be further metabolized, first to 2-methyl-1,2-propanediol and then to 2-hydroxyisobutyrate, the two dominant metabolites found in urine of volunteers and rats. The rapid oxidation of acetaldehyde suggests that its blood concentration is unlikely to rise above normal as a result of human exposure to sources of ETBE. Single-dose toxicity tests show that ETBE has low toxicity and is essentially nonirritant to eyes and skin; it did not cause sensitization in a maximization test in guinea pigs. Neurological effects have been observed only at very high exposure concentrations. There is evidence for an effect of ETBE on the kidney of rats. Increases in kidney weight were seen in both sexes, but protein droplet accumulation (with alpha(2u)-globulin involvement) and sustained increases in cell proliferation occurred only in males. In liver, centrilobular necrosis was induced in mice, but not rats, after exposure by inhalation, although this lesion was reported in some rats exposed to very high oral doses of ETBE. The proportion of liver cells engaged in S-phase DNA synthesis was increased in mice of both sexes exposed by inhalation. ETBE has no specific effects on reproduction, development, or genetic material. Carcinogenicity studies

  11. Polybrominated diphenyl ethers (PBDEs) and thyroid hormones in cord blood

    International Nuclear Information System (INIS)

    Ding, Guodong; Yu, Jing; Chen, Limei; Wang, Caifeng; Zhou, Yijun; Hu, Yi; Shi, Rong; Zhang, Yan; Cui, Chang; Gao, Yu; Tian, Ying; Liu, Fang

    2017-01-01

    Human exposure to polybrominated diphenyl ethers (PBDEs) has been increasing over the last three decades in China and around the world. Animal studies suggest that PBDEs could reduce blood levels of thyroid hormones, but it is unclear whether PBDEs disrupt thyroid function in humans. We used data from a prospective birth cohort of 123 pregnant women who were enrolled between September 2010 and March 2011 in Shandong, China. We measured the concentrations of eight PBDE congeners (n = 106) and five thyroid hormones (n = 107) in cord serum samples. We examined the relationship between prenatal exposure to PBDEs and thyroid function (n = 90). Median concentrations of BDEs 47, 99, 100, and 153 (detection frequencies > 75%) were 3.96, 8.27, 3.31, and 1.89 ng/g lipid, respectively. A 10-fold increase in BDE-99 and Σ 4 PBDEs (the sum of BDEs 47, 99, 100, and 153) concentrations was associated with a 0.41 μg/dL (95% confidence interval [CI]: 0.10 to 0.72) and 0.37 μg/dL (95% CI: 0.06 to 0.68) increase in total thyroxine levels (TT 4 ), respectively. No associations were found between other individual congeners and any of the five thyroid hormones. Our study suggests that prenatal exposure to PBDEs may be associated with higher TT 4 in cord blood. Given the inconsistent findings across existing studies, our results need to be confirmed in additional studies. - Highlights: • Human exposure to PBDEs has been increased over recent decades in China. • PBDEs reduce thyroid hormones in animal studies, but it is unclear in humans. • We examined the relation of PBDE levels with thyroid hormones in cord blood. • Prenatal exposure to PBDEs is associated with higher total thyroxine levels. • The findings may have implications for fetal development. - Exposure to PBDEs is associated with higher total thyroxine levels in cord blood, and the findings may have implications for fetal development.

  12. Triclosan and Hydroxylated Polybrominated Diphenyl Ethers in Lake and Esturaine Sediments

    Science.gov (United States)

    Arnold, W. A.; Kerrigan, J. F.; McNeill, K.; Erickson, P. R.; Grandbois, M.

    2014-12-01

    Halogenated diphenyl ethers are a class of emerging contaminants that includes the antibacterial compound triclosan and the flame retardant polybrominated diphenyl ethers (PBDEs). Both triclosan and hydroxylated polybrominated diphenyl ethers (OH-BDEs) are known to form dioxins when exposed to sunlight in aqueous solution. Thus, it is important to understand the sources and presence of these compounds in the environment, especially because OH-BDEs are breakdown products of PBDEs and also naturally produced compounds. In this work, the levels of OH-BDEs were determined in lake sediments from Minnesota and esturaine sediments from San Francisco Bay. Both surface sediments over a broad spatial area and sediment cores were collected and analyzed. Triclosan was used as a marker of wastewater as a source of the targeted emerging contaminants. The relationship between triclosan and OH-BDE levels provides insight into the importance of natural and anthropogenic influences on the levels of OH-BDEs.

  13. Interaction of polybrominated diphenyl ethers and aerobic granular sludge: biosorption and microbial degradation.

    Science.gov (United States)

    Ni, Shou-Qing; Cui, Qingjie; Zheng, Zhen

    2014-01-01

    As a new category of persistent organic pollutants, polybrominated diphenyl ethers (PBDEs) have become ubiquitous global environmental contaminants. No literature is available on the aerobic biotransformation of decabromodiphenyl ether (BDE-209). Herein, we investigated the interaction of PBDEs with aerobic granular sludge. The results show that the removal of BDE-209 from wastewater is mainly via biosorption onto aerobic granular sludge. The uptake capacity increased when temperature, contact time, and sludge dosage increased or solution pH dropped. Ionic strength had a negative influence on BDE-209 adsorption. The modified pseudo first-order kinetic model was appropriate to describe the adsorption kinetics. Microbial debromination of BDE-209 did not occur during the first 30 days of operation. Further study found that aerobic microbial degradation of 4,4(')-dibromodiphenyl ether happened with the production of lower BDE congeners.

  14. Interaction of Polybrominated Diphenyl Ethers and Aerobic Granular Sludge: Biosorption and Microbial Degradation

    Directory of Open Access Journals (Sweden)

    Shou-Qing Ni

    2014-01-01

    Full Text Available As a new category of persistent organic pollutants, polybrominated diphenyl ethers (PBDEs have become ubiquitous global environmental contaminants. No literature is available on the aerobic biotransformation of decabromodiphenyl ether (BDE-209. Herein, we investigated the interaction of PBDEs with aerobic granular sludge. The results show that the removal of BDE-209 from wastewater is mainly via biosorption onto aerobic granular sludge. The uptake capacity increased when temperature, contact time, and sludge dosage increased or solution pH dropped. Ionic strength had a negative influence on BDE-209 adsorption. The modified pseudo first-order kinetic model was appropriate to describe the adsorption kinetics. Microbial debromination of BDE-209 did not occur during the first 30 days of operation. Further study found that aerobic microbial degradation of 4,4′-dibromodiphenyl ether happened with the production of lower BDE congeners.

  15. [Ether Day--no laughing matter. The birth of modern anaesthesia].

    Science.gov (United States)

    Goerig, Michael; Wulf, Hinnerk

    2013-10-01

    Since centuries the first public demonstration of the anaesthetic properties of ether by William Thomas Green Morton at the Massachusetts General Hospital in Boston on October 16th 1846 is celebrated as "Ether Day" world-wide. The news of the beneficial effects, primarily disposed as a "Yankee Invention", spread over all continents quickly. This was the result of an article, published in the Boston Medical and Surgical Journal on November 18th, 1846. It is mentioning worth that this article was written when Morton had disclosed that the used "preparation", later named as "Nostrum" or "Letheon", was sulphuric ether. The important discovery later became a patent case and was overshadowed by a long lasting priority claim. Nevertheless the readers of the New England Journal of Medicine voted in a survey that this article was the most important publication in the 200 years journals history ever. © Georg Thieme Verlag Stuttgart · New York.

  16. The hydrolysis of geminal ethers: a kinetic appraisal of orthoesters and ketals

    Directory of Open Access Journals (Sweden)

    Sonia L. Repetto

    2016-07-01

    Full Text Available A novel approach to protecting jet fuel against the effects of water contamination is predicated upon the coupling of the rapid hydrolysis reactions of lipophilic cyclic geminal ethers, with the concomitant production of a hydrophilic acyclic hydroxyester with de-icing properties (Fuel Dehydrating Icing Inhibitors - FDII. To this end, a kinetic appraisal of the hydrolysis reactions of representative geminal ethers was undertaken using a convenient surrogate for the fuel–water interface (D2O/CD3CN 1:4. We present here a library of acyclic and five/six-membered cyclic geminal ethers arranged according to their hydroxonium catalytic coefficients for hydrolysis, providing for the first time a framework for the development of FDII. A combination of 1H NMR, labelling and computational studies was used to assess the effects that may govern the observed relative rates of hydrolyses.

  17. [Questions on the first operation with ethyl ether as anaesthetic by Dr. Peter Parker].

    Science.gov (United States)

    Chen, Q

    2017-01-28

    Ethyl ether was the first accepted effective general anaesthetic. It was introduced into China by an America missionary, Dr. Peter Parker. This was one of the historical events of medical communication between China and the West. In the records of the first operation with ether, however, Dr. Parker unusually omitted the patient's medical record number and the date of the operation, while those of other operations with ether anesthetics were all available. This was very unusual for a doctor like Peter Parker who always recorded every important case in detail in the hospital reports. It seems that he deliberately rather than carelessly omitted the information for some reasons. Based on the analysis of Parker's reports, a conclusion is made that the anesthetic effect of the case was actually ineffective. Furthermore, possible answers to this are outlined and question by discussion based on the situation that Parker faced in the late Qing era.

  18. Ether in Kant and akasa in Prasastapada: Philosophy in comparative perspective

    Directory of Open Access Journals (Sweden)

    Fernando Tola

    2015-02-01

    Full Text Available The study of Indian and Western systems of Philosophy reveals many points of thematic and methodological coincidences between them. We have collected a good number of these coincidences in our recent books, where we have included many philosophical texts in Sanskrit and in European languages which contain the expression of astonishing similar ideas and theses. In the present article we add a new instance of coincidence between Indian and Western thought in relation to akasa in India (limited to the Indian philosophical system Vaisesika and ether (Aether or Äther in German in the Opus postumum of Kant. The inexistence of both akasa and ether has been established by Modern Science. Akasa and ether in India and the West, respectively, constitute a notorious example of asrayasiddha, the well-known logical defect considered by Indian Logic.

  19. Oil-in-water emulsions stabilised by cellulose ethers: stability, structure and in vitro digestion.

    Science.gov (United States)

    Borreani, Jennifer; Espert, María; Salvador, Ana; Sanz, Teresa; Quiles, Amparo; Hernando, Isabel

    2017-04-19

    The effect of cellulose ethers in oil-in-water emulsions on stability during storage and on texture, microstructure and lipid digestibility during in vitro gastrointestinal digestion was investigated. All the cellulose ether emulsions showed good physical and oxidative stability during storage. In particular, the methylcellulose with high methoxyl substituents (HMC) made it possible to obtain emulsions with high consistency which remained almost unchanged during gastric digestion, and thus could enhance fullness and satiety perceptions at gastric level. Moreover, the HMC emulsion slowed down lipid digestion to a greater extent than a conventional protein emulsion or the emulsions stabilised by the other cellulose ethers. Therefore, HMC emulsions could be used in weight management to increase satiation capacity and decrease lipid digestion.

  20. Selectivity in stripping of alkali-metal cations from crown ether carboxylate complexes

    International Nuclear Information System (INIS)

    Bartsch, R.A.; Walkowiak, W.; Robison, T.W.

    1992-01-01

    To probe the effect of structural variations within the ionophore upon the efficiency and selectivity of solvent extraction, a variety of crown ether carboxylic acids and phosphonic acid monoesters have been synthesized. In other studies the influence of the organic diluent upon extraction efficiency and selectivity has been probed for such proton-ionizable crown ethers. In the present investigation, attention is focused upon selectivity in the stripping step. Although the efficiency of metal ion stripping is often examined in solvent extraction studies, the selectivity of competitive metal ion release under different conditions is much less frequently considered. In this study, competitive stripping of metal ions from chloroform solutions of five-alkali-metal crown ether carboxylates by varying concentrations of aqueous hydrochloric acid is examined. Alkali metals used were Li, Na, K, Rb, and Cs

  1. Dimethylzinc-Initiated Radical Coupling of β-Bromostyrenes with Ethers and Amines

    DEFF Research Database (Denmark)

    Sølvhøj, Amanda Birgitte; Ahlburg, Andreas; Madsen, Robert

    2015-01-01

    A new coupling reaction has been developed in which β-bromostyrenes react with ethers and tertiary amines to introduce the styryl group in the α-position. The transformation is mediated by Me2Zn/O2 with 10 % MnCl2 and is believed to proceed by a radical addition-elimination mechanism. The ether...... and the amine are employed as solvent and the coupling takes place through the most stable α radical for unsymmetrical substrates. The products are obtained in moderate to good yields as the pure E isomers. The coupling can be achieved with a range of smaller cyclic and acyclic ethers/amines as well as various...

  2. New Calix[4]arene dibenzocrown ethers for selective sensing of cesium ion in aqueous environment

    International Nuclear Information System (INIS)

    Kim, Jong Seung; Kim, Jong Kuk; Choi, Wang Kyu; Lee, Kune Woo; Oh, Won Jin

    1997-01-01

    1,3-dialkoxycalix[4]arene dibenzocrown ethers (6-9) were successfully synthesized in the fixed 1,3-alternate conformation with over 90% yields by the reaction of corresponding 1,3dialkoxycalix[4]arenes 2-5 with dibenzodimesylate 13 in acetonitrile as a solvent in the presence of cesium carbonate as a base. In view of cyclization yield, the use of dimesylate is found to be better than that of dibenzoditosylate. With an unusual AB pattern in 1 H NMR spectrum for compound 9, it is suggested that conformational structure of 1,3-diallyloxycalix[4]arene dibenzocrown ether be less flexible than that of usual 1,3-alternate calixcrown ether, probably due to steric effects of two ally1 group. Complexation of the corresponding calix[4]arene 6-9 toward alkali metal ions using single flux method through bulk liquid membrane system was found to give a high cesium selectivity. 28 refs., 1 tab., 1 fig

  3. Structural characterization of ether lipids from the archaeon Sulfolobus islandicus by high-resolution shotgun lipidomics

    DEFF Research Database (Denmark)

    Jensen, Sara Munk; Brandl, Martin; Treusch, Alexander H

    2015-01-01

    The molecular structures, biosynthetic pathways and physiological functions of membrane lipids produced by organisms in the domain Archaea are poorly characterized as compared with that of counterparts in Bacteria and Eukaryota. Here we report on the use of high-resolution shotgun lipidomics......-resolution Fourier transform mass spectrometry using an ion trap-orbitrap mass spectrometer. This analysis identified five clusters of molecular ions that matched ether lipids in the database with sub-ppm mass accuracy. To structurally characterize and validate the identities of the potential lipid species, we...... performed structural analysis using multistage activation on the ion trap-orbitrap instrument as well as tandem mass analysis using a quadrupole time-of-flight machine. Our analysis identified four ether lipid species previously reported in Archaea, and one ether lipid species that had not been described...

  4. APPLICATION OF PHOTOCATALYTIC PROCESS FOR REMOVAL OF METHYL TERT-BUTYL ETHER FROM HIGHLYCONTAMINATED WATER

    Directory of Open Access Journals (Sweden)

    A. Mesdaghinia

    2007-09-01

    Full Text Available The oxygenate methyl tert-butyl ether is added to gasoline to increase the octane level and to reduce carbon monoxide and hydrocarbon emissions by vehicles. The high mobility, water solubility, and resistance to natural attenuation associated with methyl tert-butyl ether may result in contamination of ground and surface waters. In this research the degradation of aqueous methyl tert-butyl ether at relatively high concentrations was investigated by UV-vis/TiO2/H2O2 photocatalytic process. The effect of important operational parameters such as pH, amount of H2O2, catalyst loading, and irradiation time were also studied. Concentrations of methyl tert-butyl ether and intermediates such as tert-butyl formate and tert-butyl alcohol were measured over a 180 min period using a gas chromatograph equipped with flame ionization detector and combined with headspace sampler. Results showed that the time required for complete degradation increased from 30 to 180min, when the initial concentration was increased from 10 to 500mg/L. The first order rate constant for degradation of methyl tert-butyl ether from the hydroxyl radical was estimated to be 0.177 to 0.022 1/min as the concentration increased from 10 to 500mg/L. Study on the overall mineralization monitored by total organic carbon (TOC analysis showed that in the initial concentration of 100mg/L methyl tert-butyl ether, complete mineralization was obtained after 110min under UV-vis/TiO2/H2O2 photocatalytic process.

  5. EFFECTS OF STIMULATOR SUBSTANCES ON AEROBIC METHYL TERT-BUTYL ETHER BIODEGRADATION BY MICROBIAL CONSORTIUM

    Directory of Open Access Journals (Sweden)

    M. Farrokhi ، S. Ahmadizad

    2009-04-01

    Full Text Available In this study dissolved humic substances and yeast extract were tested in different concentrations for enhancing methyl tert-butyl ether mineralization by isolated microorganisms from a variety of sources. All experiments were conducted at a constant temperature of 25ºC. Vials of 50 mL and 125 mL volume sealed with Teflon-lined Mini-Nert caps was used for microcosm experiments. In all experiments 1% sodium azide were used as control. Samples of bacterial cultures that metabolize methyl tert-butyl ether have been analysed by direct GC analysis using flame ionization detector. Cultures able to metabolize have been found in activated sludge and soils. These microorganisms weregram-positive bacterium. An aerobic microbial consortium was enriched in laboratory for four months. Methyl tert-butyl ether has been shown to biodegrade under aerobic and co-metabolic conditions. A microbial consortium isolated from activated sludges was identified as Cocobacillus. The concentration of the initial attached biomass was about 0.11 g/L of dry weight. The maximum mineralization rate and beneficial effects of stimulator substances on aerobic biodegradation of methyl tert-butyl ether occurred with the culture by combined concentrations of 500 mg/L of yeast extract and 20 mg/L of peat humic growth support of microbial consortium within 216 h and in presence of high oxygen levels and well mixing conditions. It was shown that adding, peat humic and yeast extract together, had better stimulatory effect on methyl tert-butyl ether biodegradation. Results clearly showed a stimulatory effect on methyl tert-butyl ether consumption higher than 20%. Consortium was capable of degrading concentrations of ≤1000 mg/L, whereas concentrations of >1000 mg/L, were not degraded.

  6. Method for determination of methyl tert-butyl ether and its degradation products in water

    Science.gov (United States)

    Church, C.D.; Isabelle, L.M.; Pankow, J.F.; Rose, D.L.; Tratnyek, P.G.

    1997-01-01

    An analytical method is described that can detect the major alkyl ether compounds that are used as gasoline oxygenates (methyl tert-butyl ether, MTBE; ethyl tert-butyl ether, ETBE; and tert-amyl methyl ether, TAME) and their most characteristic degradation products (tert-butyl alcohol, TBA; tert-butyl formate, TBF; and tert-amyl alcohol, TAA) in water at sub-ppb concentrations. The new method involves gas chromatography (GC) with direct aqueous injection (DAI) onto a polar column via a splitless injector, coupled with detection by mass spectrometry (MS). DAI-GC/MS gives excellent agreement with conventional purge-and-trap methods for MTBE over a wide range of environmentally relevant concentrations. The new method can also give simultaneous identification of polar compounds that might occur as degradation products of gasoline oxygenates, such as TBA, TBF, TAA, methyl acetate, and acetone. When the method was applied to effluent from a column microcosm prepared with core material from an urban site in New Jersey, conversion of MTBE to TBA was observed after a lag period of 35 days. However, to date, analyses of water samples from six field sites using the DAI-GC/MS method have not produced evidence for the expected products of in situ degradation of MTBE.An analytical method is described that can detect the major alkyl ether compounds that are used as gasoline oxygenates (methyl tert-butyl ether, MTBE; ethyl tert-butyl ether, ETBE; and tert-amyl methyl ether, TAME) and their most characteristic degradation products (tert-butyl alcohol, TBA; tert-butyl formate, TBF; and tert-amyl alcohol, TAA) in water at sub-ppb concentrations. The new method involves gas chromatography (GC) with direct aqueous injection (DAI) onto a polar column via a splitless injector, coupled with detection by mass spectrometry (MS). DAI-GC/MS gives excellent agreement with conventional purge-and-trap methods for MTBE over a wide range of environmentally relevant concentrations. The new method

  7. The solvent extraction of carrier-free 90Y from 90Sr with crown ethers

    International Nuclear Information System (INIS)

    Chuang, J.T.; Lo, J.G.

    1995-01-01

    A simple solvent extraction method has been developed for the separation of 90 Y from 90 Sr. Crown ether dissolved in chloroform was used as a selective reagent and organic picrate anion was chosen as a counter ion. The effect of various factors on the extraction equilibrium constant of strontium log K ex = 9.15 was obtained from the study of the distribution coefficient versus to crown ether concentration. The separation method was simple, resulted high purity (>99.9%) and quantitative yield, and took less than half an hour. (author) 27 refs.; 4 figs.; 4 tabs

  8. Gold( i )-catalysed dehydrative formation of ethers from benzylic alcohols and phenols

    KAUST Repository

    Veenboer, Richard M. P.

    2015-01-01

    © The Royal Society of Chemistry 2015. We report the cross-dehydrative reaction of two alcohols to form unsymmetrical ethers using NHC-gold(i) complexes (NHC = N-heterocyclic carbene). Our progress in developing this reaction into a straightforward procedure is discussed in detail. The optimised methodology proceeds under mild reaction conditions and produces water as the sole by-product. The synthetic utility of this environmentally benign methodology is exemplified by the formation of a range of new ethers from readily available phenols bearing electron withdrawing substituents and secondary benzylic alcohols with various substituents. Finally, we present experimental results to account for the chemoselectivity obtained in these reactions.

  9. Radiation grafting from binary monomer mixtures. II. Vinyl ether of monoethanolamine and N-vinylpyrrolidone

    International Nuclear Information System (INIS)

    Nurkeeva, Zauresh S.; Abdel Aal, A.-S.; Kupchishin, Anatoliy I.; Khutoryanskiy, Vitaliy V.; Mun, Grigoriy A.; Beksyrgaeva, Aida G.

    2003-01-01

    Radiation grafting from binary monomer mixtures of vinyl ether of monoethanolamine and N-vinylpyrrolidone onto polyethylene films has been studied. The structure of the grafted films was characterized by FTIR spectroscopy. Water uptake and contact angle measurements confirmed that the grafting leads to a considerable hydrophilization of the films surface. The presence of the more active N-vinylpyrrolidone enhances the grafting of the less active vinyl ether of monoethanolamine. Sorption properties of grafted films with respect to copper (II) ions have been studied

  10. Antibacterial activity of berberine-NorA pump inhibitor hybrids with a methylene ether linking group.

    Science.gov (United States)

    Samosorn, Siritron; Tanwirat, Bongkot; Muhamad, Nussara; Casadei, Gabriele; Tomkiewicz, Danuta; Lewis, Kim; Suksamrarn, Apichart; Prammananan, Therdsak; Gornall, Karina C; Beck, Jennifer L; Bremner, John B

    2009-06-01

    Conjugation of the NorA substrate berberine and the NorA inhibitor 5-nitro-2-phenyl-1H-indole via a methylene ether linking group gave the 13-substituted berberine-NorA inhibitor hybrid, 3. A series of simpler arylmethyl ether hybrid structures were also synthesized. The hybrid 3 showed excellent antibacterial activity (MIC Staphylococcus aureus, 1.7 microM), which was over 382-fold more active than the parent antibacterial berberine, against this bacterium. This compound was also shown to block the NorA efflux pump in S. aureus.

  11. Unusual selectivity-determining factors in the phosphine-free Heck arylation of allyl ethers

    DEFF Research Database (Denmark)

    Ambrogio, I.; Fabrizi, G.; Cacchi, S.

    2008-01-01

    The Heck reaction of aryl iodides and bromides with allyl ethers has been investigated. Using phosphinefree Pd(OAc)(2) in DNIF at 90 degrees C in the presence of Bu4NOAc, the reaction gave cinnamyl derivatives, usually in good to high yields, with a wide range of aryl halides. The reaction...... tolerates a variety of functional groups, including ether, amide, alcohol, aldehyde, ketone, ester, cyano, carboxylic acid, and nitro groups. Ortho-substituted arylating agents afforded moderate yields in some cases, though good to high yields were obtained with o-iodotoluene, iodovanillin, and 1...

  12. Regioselectivity of tributyltin ether mediated alkylations. A 119Sn and 13C NMR study

    International Nuclear Information System (INIS)

    Cruzado, C.; Bernabe, M.; Martin-Lomas, M.

    1989-01-01

    The 119 Sn and 13 C NMR spectra of the stannylated species resulting from the treatment of conformationally rigid polyhydroxylated compounds with bis(tributyltin) oxide have been determined and the effect of N-methylimidazole, added as catalyst in tributyltin ether mediated regioselective alkylations, has been investigated. The observed signal intensity changes, upfield shifts, signal broadenings, and the results of variable temperature experiments have been interpreted as indicative of the selective formation of pentacoordinated tin species, involving conveniently disposed adjacent hydroxyl groups, on addition of the catalyst. On these bases, a mechanistic hypothesis for the observed regioselectivity of N-methylimidazole-catalyzed tributyltin ether mediated benzylations is proposed. 13 references, 5 tables

  13. Reactions of phenols and alcohols over thoria: mechanism of ether formation

    International Nuclear Information System (INIS)

    Karuppannasamy, S.; Narayanan, K.; Pillai, C.N.

    1980-01-01

    The dehydration of phenols and alkylation of phenols by alcohols over thoria were studied at 400 to 500 0 C and atmospheric pressure. Phenol and cresols, when dehydrated gave diaryl ethers as main products. With para-substituted phenols such as p-methoxy, p-t-butyl, p-chloro, and p-nitrophenol no ether formation was noticed. All the reactions were accompanied by considerable amount of coke formation. Alkylation of phenols by alcohols gave a mixture of O- and C-alkylated products under the same reaction conditions. O-alkylation and C-alkylation are parallel reactions. The mechanistic aspects of the reactions are discussed. 3 figures, 3 tables

  14. Possible applications of crown-ethers to metal extraction using liquid membrane technology - a literature survey

    International Nuclear Information System (INIS)

    Dozol, M.

    1990-01-01

    Ether-crowns, discovered in 1967 by J.C. PEDERSEN, exhibit attractive complexive and extractive properties, enhanced in various fields, such as analytical chemistry, chemical synthesis, field of biology, or extractive chemistry. The investigations carried out on these macrocyclic compounds are continually increasing, as show in international literature. Among the focus of interest, the applications to metal extraction are extensively studied with crown compounds present in liquid phase or impregnated on supports (membranes or resins). The goal of this paper is to describe the application of crown-ethers to metal extraction, using liquid membrane processes. 69 refs

  15. Evaluation of various Crown ethers for the supercritical fluid extraction of uranium from nitric acid medium

    International Nuclear Information System (INIS)

    Kumar, Pradeep; Rao, Ankita; Ramakumar, K.L.

    2009-01-01

    Various crowns have been evaluated for supercritical fluid extraction of uranium from nitric acid medium employing HPFOA as counter ion. Uranium extraction efficiency was found to be influenced by cavity size of crown ether and nature of substituents. Complexation tendency of UO 2 2+ increases with increasing cavity size of crown ether. Electron withdrawing substituents decreased the extraction efficiency which could be attributed to decrease in the basicity of four oxygen atoms and hence their bonding ability. Whereas electron donating substituents increased the efficiency due to increases in basicity of oxygen atoms and hence in increase in bonding ability. (author)

  16. Insecticidal activity of the petroleum ether extract of Ageratum Conyzoides L

    International Nuclear Information System (INIS)

    Calle, Jairo; Rivera, Augusto

    1990-01-01

    We have determined the insecticidal activity of the petroleum ether (bp 40-60o C) extract of Ageratum Conyzoides L. Towards mosca domestica (diptera) third stage larvae and cynthia Carye (Lepidoptera) third, fourth and fifth stage larvae, being this extract also active against Acanthoscelides obtectus (Coleoptera) adults. We have isolated the known chromene precocene II from this extract, which is highly toxic to M. domestica third stage larvae under sunlight exposure, while no larvicidal effect was shown under U.V. irradiation or in dark. We have also identified two flavonoids: Eupalestin and lucidin dimethyl ether, which insecticidal role in this extract has not been determinate

  17. 40 CFR 63.63 - Deletion of ethylene glycol monobutyl ether from the list of hazardous air pollutants.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Deletion of ethylene glycol monobutyl... Quantity Designations, Source Category List § 63.63 Deletion of ethylene glycol monobutyl ether from the list of hazardous air pollutants. The substance ethylene glycol monobutyl ether (EGBE,2-Butoxyethanol...

  18. DFT study on the adsorption of diethyl, ethyl methyl, and dimethyl ethers on the surface of gallium doped graphene

    Energy Technology Data Exchange (ETDEWEB)

    Shokuhi Rad, Ali, E-mail: a.shokuhi@gmail.com [Department of Chemical Engineering, Qaemshahr Branch, Islamic Azad University, Qaemshahr (Iran, Islamic Republic of); Sani, Emad; Binaeian, Ehsan [Department of Chemical Engineering, Qaemshahr Branch, Islamic Azad University, Qaemshahr (Iran, Islamic Republic of); Peyravi, Majid; Jahanshahi, Mohsen [Faculty of Chemical Engineering, Babol University of Technology, Babol (Iran, Islamic Republic of)

    2017-04-15

    Highlights: • Adsorption of three ether molecules on the surface of Ga-doped graphene has been investigated. • High degree of adsorption for all analytes is found. • Ga-doped graphene shows p-type semiconductor property upon adsorption of ether molecules. - Abstract: In this study, we used density functional theory (DFT) to search on the adsorption properties of three important compounds of ether family; diethyl ether (DEE), ethyl methyl ether (EME), and dimethyl ether (DME) on the surface of Gallium doped graphene (GaG). We used three functionals (B3LYP, wb97xd, and MPW1PW91) for optimization and calculation of adsorption energy. After fully optimization, we scrutinized on the charge allocations on the adsorbed ethers as well as GaG (at the area of interaction) based on natural bond orbitals (NBO). Besides, we have calculated the amount of charge transfer upon adsorption of each analyte. We revel that GaG is an ideal adsorbent for chemisorption of all above-mentioned ethers. There is a little difference between the values of adsorption; −123.5, −120, and −118.3 kJ/mol (based on wb97xd) for DEE, EME, and DME, respectively. We found significant changes in the electronic structure of both adsorbent and adsorbate upon adsorption. Moreover, results of charge analyses confirm GaG is a p-type semiconductor.

  19. DFT study on the adsorption of diethyl, ethyl methyl, and dimethyl ethers on the surface of gallium doped graphene

    International Nuclear Information System (INIS)

    Shokuhi Rad, Ali; Sani, Emad; Binaeian, Ehsan; Peyravi, Majid; Jahanshahi, Mohsen

    2017-01-01

    Highlights: • Adsorption of three ether molecules on the surface of Ga-doped graphene has been investigated. • High degree of adsorption for all analytes is found. • Ga-doped graphene shows p-type semiconductor property upon adsorption of ether molecules. - Abstract: In this study, we used density functional theory (DFT) to search on the adsorption properties of three important compounds of ether family; diethyl ether (DEE), ethyl methyl ether (EME), and dimethyl ether (DME) on the surface of Gallium doped graphene (GaG). We used three functionals (B3LYP, wb97xd, and MPW1PW91) for optimization and calculation of adsorption energy. After fully optimization, we scrutinized on the charge allocations on the adsorbed ethers as well as GaG (at the area of interaction) based on natural bond orbitals (NBO). Besides, we have calculated the amount of charge transfer upon adsorption of each analyte. We revel that GaG is an ideal adsorbent for chemisorption of all above-mentioned ethers. There is a little difference between the values of adsorption; −123.5, −120, and −118.3 kJ/mol (based on wb97xd) for DEE, EME, and DME, respectively. We found significant changes in the electronic structure of both adsorbent and adsorbate upon adsorption. Moreover, results of charge analyses confirm GaG is a p-type semiconductor.

  20. Chemoselective Activation of Trimethylsilyl Enol Ether Functionalities in the Presence of Silyl-Protected Alcohols by Trimethylsilyl-Nonaflyl Exchange

    Czech Academy of Sciences Publication Activity Database

    Boltukhina, Ekaterina; Sheshenev, Andrey; Lyapkalo, Ilya

    -, č. 21 (2011), s. 3507-3515 ISSN 0039-7881 Institutional research plan: CEZ:AV0Z40550506 Keywords : biphasic catalysis * crown ether * sulfonylating reagent * trialkylsilyl ethers * alkenyl nonaflates Subject RIV: CC - Organic Chemistry Impact factor: 2.466, year: 2011

  1. Isoflurane is a suitable alternative to ether for anesthetizing rats prior to euthanasia for gene expression analysis.

    Science.gov (United States)

    Nakatsu, Noriyuki; Igarashi, Yoshinobu; Aoshi, Taiki; Hamaguchi, Isao; Saito, Masumichi; Mizukami, Takuo; Momose, Haruka; Ishii, Ken J; Yamada, Hiroshi

    2017-01-01

    Diethyl ether (ether) had been widely used in Japan for anesthesia, despite its explosive properties and toxicity to both humans and animals. We also had used ether as an anesthetic for euthanizing rats for research in the Toxicogenomics Project (TGP). Because the use of ether for these purposes will likely cease, it is required to select an alternative anesthetic which is validated for consistency with existing TGP data acquired under ether anesthesia. We therefore compared two alternative anesthetic candidates, isoflurane and pentobarbital, with ether in terms of hematological findings, serum biochemical parameters, and gene expressions. As a result, few differences among the three agents were observed. In hematological and serum biochemistry analysis, no significant changes were found. In gene expression analysis, four known genes were extracted as differentially expressed genes in the liver of rats anesthetized with ether, isoflurane, or pentobarbital. However, no significant relationships were detected using gene ontology, pathway, or gene enrichment analyses by DAVID and TargetMine. Surprisingly, although it was expected that the lung would be affected by administration via inhalation, only one differentially expressed gene was extracted in the lung. Taken together, our data indicate that there are no significant differences among ether, isoflurane, and pentobarbital with respect to effects on hematological parameters, serum biochemistry parameters, and gene expression. Based on its smallest affect to existing data and its safety profile for humans and animals, we suggest isoflurane as a suitable alternative anesthetic for use in rat euthanasia in toxicogenomics analysis.

  2. Thermodynamic modeling of ternary and quaternary (liquid + liquid) systems containing water, FeCl3, HCl and diisopropyl ether

    NARCIS (Netherlands)

    Milosevic, M.; Hendriks, I.; Smits, R.E.R.; Schuur, B.; Haan, de A.B.

    2013-01-01

    Liquid–liquid extraction using ethers as solvents is a potentially energy saving alternative for the concentration of aqueous ferric chloride solutions. Adequate thermodynamic models that describe the behavior of the resulting quaternary systems (FeCl3, ether, acid and water) are not available in

  3. Crosslinked poly(vinyl alcohol)/sulfonated poly(ether ether ketone) blend membranes for fuel cell applications - Surface energy characteristics and proton conductivity

    Energy Technology Data Exchange (ETDEWEB)

    Kanakasabai, P.; Vijay, P.; Deshpande, Abhijit P.; Varughese, Susy [Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai 600 036 (India)

    2011-02-01

    Ionic polymers, their blends and composites are considered potential candidates for application as electrolytes in fuel cells. While developing new materials for membranes, it is important to understand the interactions of these electrolytic materials with electrodes/catalysts and with reactants/products. Some of these interactions can be understood by estimating the surface energy and wettability of the membrane materials. In this work, polyvinyl alcohol with varying degrees of sulfonation and its blend with sulfonated poly(ether ether ketone) are prepared and studied for their wettability characteristics using goniometry. The surface energy and its components are estimated using different approaches and compared. Properties such as the ion-exchange capacity, the proton conductivity and the water sorption/desorption behaviour are also investigated to understand the relationship with wettability and surface energy and its components. Among the different methods, the van Oss acid-base and the modified Berthelot approaches yield comparable estimates for the total surface energy. (author)

  4. Proton-conducting membranes based on benzimidazole-containing sulfonated poly(ether ether ketone) compared with their carboxyl acid form

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hongtao; Wu, Jing; Zhao, Chengji; Zhang, Gang; Zhang, Yang; Shao, Ke; Xu, Dan; Lin, Haidan; Han, Miaomiao; Na, Hui [Alan G MacDiarmid Institute, College of Chemistry, Jilin University, Changchun 130012 (China)

    2009-10-15

    A series of sulfonated poly(ether ether ketone) containing pendant carboxyl (C-SPEEKs) have been synthesized using a nucleophilic polycondesation reaction. A condensation reaction between 1,2-diaminobenzene and carboxyl resulted in a new series of copolymers containing benzimidazole groups (SPEEK-BIms). The expected structures of the sulfonated copolymers are confirmed by {sup 1}H NMR. The dependence of ion exchange capacity, water uptake, proton conductivity and methanol diffusion coefficient of SPEEK-BIm membranes has been studied and compared with their carboxyl acid form. The results suggest that the introduction of benzimidazole groups may be responsible for many excellent properties of the membranes for fuel cell. It is noticeable that the markedly improved oxidative stability is benefit for the application of membrane. (author)

  5. Di-hydroxybenzenes: Catechol, resorcinol, and hydroquinone

    International Nuclear Information System (INIS)

    Verevkin, Sergey P.; Kozlova, Svetlana A.

    2008-01-01

    Molar enthalpies of sublimation of 1,2-di-hydroxybenzene, 1,3-di-hydroxybenzene, and 1,4-di-hydroxybenzene were obtained from the temperature dependence of the vapor pressure measured by the transpiration method. The molar enthalpies of fusion of 1,2- and 1,4-isomers were measured by differential scanning calorimetry (DSC). A large number of the primary experimental results on the temperature dependences of vapor pressure and phase transitions have been collected from the literature and have been treated in a uniform manner in order to derive sublimation, vaporization and fusion enthalpies of di-hydroxybenzenes at the reference temperature 298.15 K. The data sets on phase transitions were checked for internal consistency. This collection together with the new experimental results reported here has helped to resolve contradictions in the available thermochemical data and to recommend consistent and reliable sublimation, vaporization and fusion enthalpies for all three isomers under study

  6. Polyether ether ketone encased monolith frits made of polyether ether ketone tubing with a 0.25 mm opening resulting in an improved separation performance in liquid chromatography.

    Science.gov (United States)

    Park, Sin Young; Cheong, Won Jo

    2016-05-01

    Tiny polyether ether ketone encased monolith frits have been prepared by modified catalytic sulfonation of the inner surface of polyether ether tubing (1.6 mm od, 0.25 mm id) followed by modified formation of organic monolith and cutting of the tubing into slices. The frit was placed below the central hole of the column outlet union and supported by a combination of a silica capillary (0.365 mm od, 0.05 mm id) and a polyether ether ketone sleeve (1.6 mm od, 0.38 mm id) tightened with a nut and a ferrule when the column was packed to prevent sinking of the frit element into the union hole (0.25 mm opening) otherwise. The column packed this way with the frits investigated in this study has shown better separation performance owing to the reduced frit volume in comparison to the column packed with a commercial stainless-steel screen frit. This study establishes the strategy of disposable microcolumns in which cheap disposable frits are used whenever the column is re-packed to yield columns of even better chromatographic performance than the columns with commercial frits. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Determination of alcohols, ethers and organic acids in irradiated sweet potato wine by capillary gas chromatography

    International Nuclear Information System (INIS)

    Zhou Yingcai; Yuan Bihuai; Xu Peishu; Wang Xiuying

    1986-01-01

    Alcohols, ethers and organic acids in irradiated sweet potato wine have been determined with capillary GC. The results show that the contents of some components have changed after irradiation, but no new species are formed. The G values of the changed components have been calculated

  8. Modelling of phase equilibria of glycol ethers mixtures using an association model

    DEFF Research Database (Denmark)

    Garrido, Nuno M.; Folas, Georgios; Kontogeorgis, Georgios

    2008-01-01

    Vapor-liquid and liquid-liquid equilibria of glycol ethers (surfactant) mixtures with hydrocarbons, polar compounds and water are calculated using an association model, the Cubic-Plus-Association Equation of State. Parameters are estimated for several non-ionic surfactants of the polyoxyethylene ...

  9. Ketene as a Reaction Intermediate in the Carbonylation of Dimethyl Ether to Methyl Acetate over Mordenite

    DEFF Research Database (Denmark)

    Rasmussen, Dominik Bjørn; Christensen, Jakob Munkholt; Temel, Burcin

    2015-01-01

    Unprecedented insight into the carbonylation of dimethyl ether over Mordenite is provided through the identification of ketene (CH2CO) as a reaction intermediate. The formation of ketene is predicted by detailed DFT calculations and verified experimentally by the observation of doubly deuterated ...

  10. Long term studies on the anaerobic biodegradability of MTBE and other gasoline ethers

    DEFF Research Database (Denmark)

    Waul, Christopher Kevin; Arvin, Erik; Schmidt, Jens Ejbye

    2009-01-01

    to investigate the anaerobic biodegradability of MTBE and other gasoline ethers. Inoculums collected from various environments were used, along with different electron acceptors. Only one set of the batch experiments showed a 30-60% conversion of MTBE to tert-butyl alcohol under Fe(III)-reducing conditions...

  11. Thermodynamicy of Catalytic Formation of Dimethyl Ether from Methanol in Acidic Zeolites

    Czech Academy of Sciences Publication Activity Database

    Hyťha, Marek; Štich, I.; Gale, J. D.; Terakura, K.; Payne, M.

    2001-01-01

    Roč. 7, č. 12 (2001), s. 2521-2527 ISSN 0947-6539 Institutional research plan: CEZ:AV0Z1010914 Keywords : dimethyl ether * formation * theoretical study Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 4.614, year: 2001

  12. Effects of poly-ether B on proteome and phosphoproteome expression in biofouling Balanus amphitrite cyprids

    KAUST Repository

    Dash, Swagatika; Chandramouli, Kondethimmanahalli; Zhang, Yu; Qian, Pei Yuan

    2012-01-01

    in recent years, although the mechanism by which they inhibit fouling is yet to be investigated. Poly-ether B has shown promise in the non-toxic inhibition of larval barnacle attachment. Hence, in this study, multiplex two-dimensional electrophoresis (2-DE

  13. Sodium lauryl ether sulfate (SLES) degradation by nitrate-reducing bacteria

    NARCIS (Netherlands)

    Silva Paulo, da Ana; Aydin, Rozelin; Dimitrov, Mauricio R.; Vreeling, Harm; Cavaleiro, Ana J.; García-Encina, Pedro A.; Stams, Fons; Plugge, Caroline M.

    2017-01-01

    The surfactant sodium lauryl ether sulfate (SLES) is widely used in the composition of detergents and frequently ends up in wastewater treatment plants (WWTPs). While aerobic SLES degradation is well studied, little is known about the fate of this compound in anoxic environments, such as

  14. Toluidine blue-sodium lauryl ether sulfate complexes : Influence of ethylene oxide length

    NARCIS (Netherlands)

    Vleugels, L.F.W.; Féat, A.; Voets, I.K.; Tuinier, R.

    2017-01-01

    Sodium Lauryl Ether Sulfates (SLES) are an increasingly important and versatile type of surfactants. The complexation between ortho-Toluidine blue (TBO) and a homologous series of SLES, including Sodium Lauryl Sulfate (SDS) without Ethylene Oxide (EO), has been investigated using visible

  15. Polycation–sodium lauryl ether sulfate-type surfactant complexes : influence of ethylene oxide length

    NARCIS (Netherlands)

    Vleugels, L.F.W.; Pollet, J.; Tuinier, R.

    2015-01-01

    Polyelectrolyte-surfactant complexes (PESC) are a class of materials which form spontaneously by self-assembly driven by electrostatic and hydrophobic interactions. PESC containing sodium lauryl ether sulfates (SLES) have found wide application in hair care products like shampoo. Typically, SLES

  16. Polycation-Sodium Lauryl Ether Sulfate-Type Surfactant Complexes : Influence of Ethylene Oxide Length

    NARCIS (Netherlands)

    Vleugels, Leo F. W.; Pollet, Jennifer; Tuinier, Remco

    2015-01-01

    Poiyelectrolyte-surfactant complexes (PESC) are a class of materials which form spontaneously by self-assembly driven by electrostatic and hydrophobic interactions. PESC containing sodium lauryl ether Sulfates (SLES) have found wide application in hair care products like shampoo. Typically, SLES

  17. DETERMINATION OF SURFACTANT SODIUM LAURYL ETHER SULFATE BY ION PAIRING CHROMATOGRAPHY WITH SUPPRESSED CONDUCTIVITY DETECTION

    Science.gov (United States)

    A method for the determination of the anionic Steol CS-330 surfactant is described. CS-330 is a complex mixture of oligomers due to the various sizes of fatty alcohols and the number of moles of the ethoxylation. The main component of CS-330 is sodium lauryl ether sulfate (SLES)....

  18. Screening of ligands for the Ullmann synthesis of electron-rich diaryl ethers.

    Science.gov (United States)

    Otto, Nicola; Opatz, Till

    2012-01-01

    In the search for new ligands for the Ullmann diaryl ether synthesis, permitting the coupling of electron-rich aryl bromides at relatively low temperatures, 56 structurally diverse multidentate ligands were screened in a model system that uses copper iodide in acetonitrile with potassium phosphate as the base. The ligands differed largely in their performance, but no privileged structural class could be identified.

  19. Synthesis of enantiomerically pure thiocrown ethers derived from 1,1'-binaphthalene-2,2'-diol

    NARCIS (Netherlands)

    Stock, H. Thijs; Kellogg, Richard M.

    1996-01-01

    Synthetic methodology is given for the preparation of two different types of thiocrown ethers from optically pure 1,1'-binaphthalene-2,2'-diol (10). The conceptually simplest approach starts from optically pure 10 itself, which is alkylated (4 equiv of K2CO3 in DMF at 110 degrees C) with

  20. On-board conversion of methanol to dimethyl ether as an alternative diesel fuel

    Energy Technology Data Exchange (ETDEWEB)

    Armbruster, H; Heinzelmann, G; Struis, R; Stucki, S [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    The catalytic dehydration of methanol to dimethyl ether was investigated for application on-board a methanol fuelled vehicle. Several catalysts have been tested in a fixed bed reactor. Our approach is to develop a small and efficient reactor converting liquid MeOH under pressure and at low reaction temperatures. (author) 2 figs., 5 refs.

  1. Ring-opening of cyclic ethers with carbon–carbon bond formation by Grignard reagents

    DEFF Research Database (Denmark)

    Christensen, Stig Holden; Holm, Torkil; Madsen, Robert

    2014-01-01

    The ring-opening of cyclic ethers with concomitant C–C bond formation was studied with a number of Grignard reagents. The transformation was performed in a sealed vial by heating to ∼160 °C in an aluminum block or at 180 °C in a microwave oven. Good yields of the product alcohols were obtained...

  2. Ether gas-sensor based on Au nanoparticles-decorated ZnO microstructures

    Directory of Open Access Journals (Sweden)

    Roberto López

    Full Text Available An ether gas-sensor was fabricated based on gold nanoparticles (Au-NPs decorated zinc oxide microstructures (ZnO-MS. Scanning electron microscope (SEM and high-resolution transmission electron microscope (HRTEM measurements were performed to study morphological and structural properties, respectively, of the ZnO-MS. The gas sensing response was evaluated in a relatively low temperature regime, which ranged between 150 and 250 °C. Compared with a sensor fabricated from pure ZnO-MS, the sensor based on Au-NPs decorated ZnO-MS showed much better ether gas response at the highest working temperature. In fact, pure ZnO-MS based sensor only showed a weak sensitivity of about 25%. The improvement of the ether gas response for sensor fabricated with Au-NPs decorated ZnO-MS was attributed to the catalytic activity of the Au-NPs. Keywords: ZnO microstructures, Au nanoparticles, Ether, Gas sensor

  3. IRIS Toxicological Review of Ethylene Glycol Mono Butyl Ether (Egbe) (Final Report)

    Science.gov (United States)

    EPA has finalized the Toxicological Review of Ethylene Glycol Mono Butyl Ether: in support of the Integrated Risk Information System (IRIS). Now final, this assessment may be used by EPA’s program and regional offices to inform decisions to protect human health.

  4. IRIS Toxicological Review of Ethylene Glycol Mono-Butyl Ether (Egbe) (Interagency Science Discussion Draft)

    Science.gov (United States)

    EPA released the draft report, Toxicological Review for Ethylene Glycol Mono-Butyl Ether , that was distributed to Federal agencies and White House Offices for comment during the Science Discussion step of the IRIS Assessment Development Process. Comments received from ot...

  5. Stereospecific nickel-catalyzed cross-coupling reactions of alkyl ethers: enantioselective synthesis of diarylethanes.

    Science.gov (United States)

    Taylor, Buck L H; Swift, Elizabeth C; Waetzig, Joshua D; Jarvo, Elizabeth R

    2011-01-26

    Secondary benzylic ethers undergo stereospecific substitution reactions with Grignard reagents in the presence of nickel catalysts. Reactions proceed with inversion of configuration and high stereochemical fidelity. This reaction allows for facile enantioselective synthesis of biologically active diarylethanes from readily available optically enriched carbinols.

  6. Photolytic degradation of polybromodiphenyl ethers under UV-lamp and solar irradiations

    Energy Technology Data Exchange (ETDEWEB)

    Shih, Yang-hsin, E-mail: yhs@nchu.edu.tw [Department of Soil and Environmental Sciences, National Chung Hsing University, Taichung 402, Taiwan (China); Wang, Chun-Kang [Department of Soil and Environmental Sciences, National Chung Hsing University, Taichung 402, Taiwan (China)

    2009-06-15

    Polybromodiphenyl ethers (PBDEs) are widely used flame retardant additives and have been mainly used in polymers for many plastic and electronic products. PBDEs have been found to bioaccumulate in both aquatic and terrestrial ecosystems and even human bodies. The technical product with the highest use is decabrominated diphenyl ether (BDE-209). Therefore, we chose to examine the solar and UV-lamp degradation of BDE-209. A linear increase of the photodegradation rate constant for BDE-209 was observed with the solar light intensity. The degradation reactions follow the pseudo-first-order kinetics. The photodegradation of BDE-209 produced other less brominated diphenyl ethers under ultraviolet light exposure, suggesting that the photodegradation of BDE-209 is a sequential dehalogenation mechanism. BDE-209 underwent rapid reductive debromination in these photodecomposition experiments. The formation rate constants of three nonabromodiphenyl ethers increase with the order of BDE-206, BDE-207 and BDE-208, indicating debromination mainly occurred at para > meta > ortho positions. These findings of the process properties and reductive debromination mechanism of the photolytic degradation of PBDEs can facilitate the design of remediation processes and also aid in predicting their fate in the environment.

  7. Additive effects on phase transition and interactions in poly(vinyl methyl ether) solutions

    Czech Academy of Sciences Publication Activity Database

    Starovoytova, Larisa; Šťastná, J.; Šturcová, Adriana; Konefal, Rafal; Dybal, Jiří; Velychkivska, Nadiia; Radecki, M.; Hanyková, L.

    2015-01-01

    Roč. 7, č. 12 (2015), s. 2572-2583 ISSN 2073-4360 R&D Projects: GA ČR(CZ) GA13-23392S Institutional support: RVO:61389013 Keywords : additives * LCST * poly(vinyl methyl ether) Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.944, year: 2015

  8. Effects of poly-ether B on proteome and phosphoproteome expression in biofouling Balanus amphitrite cyprids

    KAUST Repository

    Dash, Swagatika

    2012-04-01

    Biofouling is ubiquitous in marine environments, and the barnacle Balanus amphitrite is one of the most recalcitrant and aggressive biofoulers in tropical waters. Several natural antifoulants that were claimed to be non-toxic have been isolated in recent years, although the mechanism by which they inhibit fouling is yet to be investigated. Poly-ether B has shown promise in the non-toxic inhibition of larval barnacle attachment. Hence, in this study, multiplex two-dimensional electrophoresis (2-DE) was applied in conjunction with mass spectrometry to investigate the effects of poly-ether B on barnacle larvae at the molecular level. The cyprid proteome response to poly-ether B treatment was analyzed at the total proteome and phosphoproteome levels, with 65 protein and 19 phosphoprotein spots found to be up- or down-regulated. The proteins were found to be related to energy-metabolism, oxidative stress, and molecular chaperones, thus indicating that poly-ether B may interfere with the redox-regulatory mechanisms governing the settlement of barnacle larvae. The results of this study demonstrate the usefulness of the proteomic technique in revealing the working mechanisms of antifouling compounds. © 2012 Copyright Taylor and Francis Group, LLC.

  9. Polyaza crown ether as non-nucleosidic building blocks in DNA-conjugates

    DEFF Research Database (Denmark)

    Jakobsen, Ulla; Rohr, Katja; Madsen, Rasmus K

    2007-01-01

    The synthesis of amphiphilic polyaza crown ether monomers X (palmityl-substituted), Y (cholesteryl-substituted) and Z (dipalmityl-subtituted) and their incorporation into oligonucleotides are described. Their effects on thermal duplex stability were investigated by UV melting curve analysis. Ther...

  10. Risicogrenzen voor MTBE (Methyl tertiair-Butyl Ether) in bodem, sediment, grondwater, oppervlaktewater en voor drinkwaterbereiding

    NARCIS (Netherlands)

    Swartjes FA; Baars AJ; Fleuren RHLJ; Otte PF; LER

    2004-01-01

    Recentelijk is politieke commotie ontstaan ten gevolge van de mogelijke schadelijke gezondheidseffecten van Methyl tertiair-Butyl Ether (MTBE). Dit was reden voor het ministerie van VROM om het RIVM te verzoeken risicogrenzen voor MTBE in bodem, sediment, grondwater, oppervlaktewater, drinkwater en

  11. Polyacrylonitrile (PAN)/crown ether composite nanofibers for the selective adsorption of cations

    NARCIS (Netherlands)

    Tas, Sinem; Kaynan, Ozge; Ozden-Yenigun, Elif; Nijmeijer, Dorothea C.

    2016-01-01

    In this study, we prepared electrospun polyacrylonitrile (PAN) nanofibers functionalized with dibenzo-18-crown-6 (DB18C6) crown ether and showed the potential of these fibers for the selective recovery of K+ from other both mono- and divalent ions in aqueous solutions. Nanofibers were characterized

  12. DERMAL, ORAL, AND INHALATION PHARMACOKINETICS OF METHYL TERTIARY BUTYL ETHER (MTBE) IN HUMAN VOLUNTEERS

    Science.gov (United States)

    Methyl tertiary butyl ether (MTBE), a gasoline additive, used to increase octane and reduce carbon monoxide emissions and ozone precursors has contaminated drinking water leading to exposure by oral, inhalation, and dermal routes. To determine its dermal, oral, and inhalation ki...

  13. DERMAL, ORAL AND INHALATION PHARMACOKINETICS OF METHYL TERTIARY-BUTYL ETHER (MTBE) IN HUMAN VOLUNTEERS

    Science.gov (United States)

    Methyl tertiary butyl ether (MTBE), a gasoline additive used to increase octane and reduce carbon monoxide emissions and ozone precursors, has contaminated drinking water and can lead to exposure by oral, inhalation, and dermal routes. To determine its dermal, oral, and inhal...

  14. INHALATION EXPOSURE TO METHYL TERT-BUTYL ETHER (MTBE) AND DIBROMOCHLOROMETHANE (DBCM) USING CONTINUOUS BREATH ANALYSIS

    Science.gov (United States)

    The oxygenate methyl tert-butyl ether (MTBE) has been added to gasoline to help meet national ambient air quality standards in those parts of the U.S. that are non-compliant for carbon monoxide. Although MTBE has provided important health benefits in terms of reduced haza...

  15. Evaluation of Efficient and Practical Methods for the Preparation of Functionalized Aliphatic Trifluoromethyl Ethers

    Directory of Open Access Journals (Sweden)

    Taras M. Sokolenko

    2017-05-01

    Full Text Available The “chlorination/fluorination” technique for aliphatic trifluoromethyl ether synthesis was investigated and a range of products with various functional groups was prepared. The results were compared with oxidative desulfurization-fluorination of xanthates with the same structure.

  16. Leaching characteristics of polybrominated diphenyl ethers (PBDEs) from flame-retardant plastics.

    Science.gov (United States)

    Kim, Yong-Jin; Osako, Masahiro; Sakai, Shin-ichi

    2006-10-01

    To investigate the effect of leachant on the leachability of polybrominated diphenyl ethers (PBDEs), we determined the leaching concentrations of PBDEs from flame-retardant plastic samples (TV housings and raw materials before molding processing) that are regarded as a source of PBDEs in landfill sites. The leachants used were distilled water, 20% methanol solution, and dissolved humic solution (DHS) of 1000 mg/l based on organic carbon. The leaching test conditions were a liquid-to-solid ratio of 100:1, and a contact period of five days, with twice-daily agitation in a temperature-controlled room of 30 degrees C without pH or ionic strength control. The leaching concentrations of PBDEs increased with increased content, and were found to be remarkably enhanced when methanol and DHS were used instead of distilled water. The enhancement of leachability in the presence of the latter was attributed to the cosolvency effect, and complex formations between the PBDEs and dissolved humic matter (DHM). PBDE concentrations in the leachate obtained from the leaching test and an actual landfill site revealed a significant presence of congeners below heptabromodiphenyl ethers (H7BDEs), detected in the leachate of the actual landfill, while significant amounts of nonabromodiphenyl ethers (N9BDEs) and decabromodiphenyl ether (D10BDE) were detected in the leachate of the leaching test.

  17. Oxidation mechanism of diethyl ether: a complex process for a simple molecule.

    Science.gov (United States)

    Di Tommaso, Stefania; Rotureau, Patricia; Crescenzi, Orlando; Adamo, Carlo

    2011-08-28

    A large number of organic compounds, such as ethers, spontaneously form unstable peroxides through a self-propagating process of autoxidation (peroxidation). Although the hazards of organic peroxides are well known, the oxidation mechanisms of peroxidizable compounds like ethers reported in the literature are vague and often based on old experiments, carried out in very different conditions (e.g. atmospheric, combustion). With the aim to (partially) fill the lack of information, in this paper we present an extensive Density Functional Theory (DFT) study of autoxidation reaction of diethyl ether (DEE), a chemical that is largely used as solvent in laboratories, and which is considered to be responsible for various accidents. The aim of the work is to investigate the most probable reaction paths involved in the autoxidation process and to identify all potential hazardous intermediates, such as peroxides. Beyond the determination of a complex oxidation mechanism for such a simple molecule, our results suggest that the two main reaction channels open in solution are the direct decomposition (β-scission) of DEE radical issued of the initiation step and the isomerization of the peroxy radical formed upon oxygen attack (DEEOO˙). A simple kinetic evaluation of these two competing reaction channels hints that radical isomerization may play an unexpectedly important role in the global DEE oxidation process. Finally industrial hazards could be related to the hydroperoxide formation and accumulation during the chain propagation step. The resulting information may contribute to the understanding of the accidental risks associated with the use of diethyl ether.

  18. Poly(ether amide) segmented block copolymers with adipicacid based tetra amide segments

    NARCIS (Netherlands)

    Biemond, G.J.E.; Feijen, Jan; Gaymans, R.J.

    2007-01-01

    Poly(tetramethylene oxide)-based poly(ether ester amide)s with monodisperse tetraamide segments were synthesized. The tetraamide segment was based on adipic acid, terephthalic acid, and hexamethylenediamine. The synthesis method of the copolymers and the influence of the tetraamide concentration,

  19. 21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.

    Science.gov (United States)

    2010-04-01

    ... in powder form having a particle size such that 100 percent will pass through a U.S. Standard Sieve No. 40 and such that not more than 10 percent will pass through a U.S. Standard Sieve No. 200. (1... analysis. (e) Other specifications and limitations. The vinyl chloride-lauryl vinyl ether copolymers...

  20. A National Probabilistic Study of Polybrominated Diphenyl Ethers in Fish from US Lakes and Reservoirs

    Science.gov (United States)

    National estimates were developed for polybrominated diphenyl ethers (PBDEs) in fish from lakes and reservoirs of the conterminous United States (excluding the Laurentian Great Lakes and Great Salt Lake) using an unequal probability design. Predator (fillet) and bottom-dweller (w...

  1. In vitro estrogenicity of polybrominated diphenyl ethers, hydroxylated PBDEs, and polybrominated bisphenol A compounds

    NARCIS (Netherlands)

    Meerts, I.A.T.M.; Letcher, R.J.; Hoving, S.; Marsh, G.; Bergman, A.; Lemmen, J.G.; Burg, van der B.; Brouwer, A.

    2001-01-01

    Polybrominated diphenyl ethers (PBDEs) are used in large quantities as additive flame retardants in plastics and textile materials. PBDEs are persistent compounds and have been detected in wildlife and in human adipose tissue and plasma samples. In this study, we investigated the (anti)estrogenic

  2. PHYSIOLOGICALLY BASED PHARMACOKINETIC MODEL FOR HUMAN EXPOSURES TO METHYL TERTIARY-BUTYL ETHER

    Science.gov (United States)

    Humans can be exposed by inhalation, ingestion, or dermal absorption to methyl tertiary-butyl ether (MTBE), an oxygenated fuel additive, from contaminated water sources. The purpose of this research was to develop a physiologically based pharmacokinetic model describing in human...

  3. Effect of electrostatic interaction on thermochemical behavior of 12-crown-4 ether in various polar solvents

    International Nuclear Information System (INIS)

    Barannikov, Vladimir P.; Guseynov, Sabir S.; Vyugin, Anatoliy I.

    2010-01-01

    The enthalpies of solution of 12-crown-4 ether have been measured in chloroform, ethyl acetate, acetone, pyridine, acetonitrile and methanol at 298.15 K. The values of enthalpy of solvation and solute-solvent interaction were determined from the obtained results and similar literature data for 12-crown-4 in solvents of various polarities. It was shown that the certain correlation is observed between the enthalpy of solute-solvent interaction and the squared dipole moment of the solvent molecules for solutions in tetrachlormethane, ethyl acetate, pyridine, acetonitrile, DMF, DMSO and propylene carbonate. This means that the electrostatic interaction of 12-crown-4 with polar solvent molecules contributes significantly to the exothermic effect of solvation. The understated negative value was found for the enthalpy of interaction of 12-crown-4 with acetone that can be connected with domination of low polar conformer of the crown ether in acetone medium. The most negative values of enthalpy of solvation are observed for solutions in chloroform and water because of hydrogen bonding between O-atoms of crown ether and molecules of the indicated solvents. This effect is not observed for methanol. The negative coefficient of pairwise solute-solute interaction in methanol indicates that the effects of solvophobic solute-solute interaction and H-bonding of the ether molecule with chain associates of methanol are not evinced in the thermochemical behavior of 12-crown-4.

  4. Novel Naphthalene Based Lariat-Type Crown Ethers Using Direct Single Electron Transfer Photochemical Strategy

    International Nuclear Information System (INIS)

    Park, Hea Jung; Sung, Nam Kyung; Kim, Su Rhan; Kim, Su Rhan; Ahn, So Hyun; Yoon, Ung Chan; Cho, Dae Won; Mariano, Patrick S.

    2013-01-01

    This study explored a direct SET-photochemical strategy to construct a new family of thioene conjugated-naphthalamide fluorophore based lariat-crown ethers which show strong binding properties towards heavy metal ions. Irradiations of designed nitrogen branched (trimethylsilyl)methylthio-terminated polyethylenoxy-tethered naphthalimides in acidic methanol solutions have led to highly efficient photocyclization reactions to generate naphthalamide based lariat type thiadiazacrown ethers directly in chemo- and regio-selective manners which undergo very facile secondary dehydration reactions during separation processes to produce their corresponding amidoenethio ether cyclic products tethered with electron donating diethyleneoxy- and diethyenethio-side arm chains. Fluorescence and metal cation binding properties of the lariat type enamidothio products were examined. The photocyclized amidoenethio products, thioene conjugated naphthalamide fluorophore containing lariat-thiadiazacrowns exhibited strong fluorescence emissions in region of 330-450 nm along with intramolecular exciplex emissions in region of 450-560 nm with their maxima at 508 nm. Divalent cation Hg 2+ and Pb 2+ showed strong binding to sulfur atom(s) in side arm chain and atoms in enethiadiazacrown ether rings which led to significant enhancement of fluorescence from its chromophore singlet excited state and concomitant quenching of exciplex emission. The dual fluorescence emission responses towards divalent cations might provide a new guide for design and development of fluorescence sensors for detecting those metals

  5. Novel Naphthalene Based Lariat-Type Crown Ethers Using Direct Single Electron Transfer Photochemical Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hea Jung; Sung, Nam Kyung; Kim, Su Rhan; Kim, Su Rhan; Ahn, So Hyun; Yoon, Ung Chan [Pusan National Univ., Busan (Korea, Republic of); Cho, Dae Won [Yeungnam Univ., Geoungsan (Korea, Republic of); Mariano, Patrick S. [Univ. of New Mexico, Albuquerque (United States)

    2013-12-15

    This study explored a direct SET-photochemical strategy to construct a new family of thioene conjugated-naphthalamide fluorophore based lariat-crown ethers which show strong binding properties towards heavy metal ions. Irradiations of designed nitrogen branched (trimethylsilyl)methylthio-terminated polyethylenoxy-tethered naphthalimides in acidic methanol solutions have led to highly efficient photocyclization reactions to generate naphthalamide based lariat type thiadiazacrown ethers directly in chemo- and regio-selective manners which undergo very facile secondary dehydration reactions during separation processes to produce their corresponding amidoenethio ether cyclic products tethered with electron donating diethyleneoxy- and diethyenethio-side arm chains. Fluorescence and metal cation binding properties of the lariat type enamidothio products were examined. The photocyclized amidoenethio products, thioene conjugated naphthalamide fluorophore containing lariat-thiadiazacrowns exhibited strong fluorescence emissions in region of 330-450 nm along with intramolecular exciplex emissions in region of 450-560 nm with their maxima at 508 nm. Divalent cation Hg{sup 2+} and Pb{sup 2+} showed strong binding to sulfur atom(s) in side arm chain and atoms in enethiadiazacrown ether rings which led to significant enhancement of fluorescence from its chromophore singlet excited state and concomitant quenching of exciplex emission. The dual fluorescence emission responses towards divalent cations might provide a new guide for design and development of fluorescence sensors for detecting those metals.

  6. Antibiotic Potency against E. coli Is Enhanced by Channel-Forming Alkyl Lariat Ethers.

    Science.gov (United States)

    Negin, Saeedeh; Patel, Mohit B; Gokel, Michael R; Meisel, Joseph W; Gokel, George W

    2016-11-17

    Several N,N'-bis(n-alkyl-4,13-diaza[18]crown-6) lariat ethers were found to significantly enhance the potency of rifampicin and tetracycline, but not erythromycin and kanamycin, against the non-pathogenic DH5α and K-12 strains of Escherichia coli when administered at levels below their minimum inhibitory concentrations (MICs). The enhancements in antibiotic potency observed for the lariat ethers ranged from three- to 20-fold, depending on the strain of E. coli, the antibiotic, and the lengths of the alkyl chains attached at the macroring nitrogen atoms. The dialkyl lariat ethers, previously thought to only be cation carriers, formed well-behaved, ion-conducting pores in soybean asolectin membranes, as judged by planar bilayer conductance measurements. The ability of lariat ethers to form stable pores, which appeared to be aggregated, depended in part on alkyl chain length and in part on the composition of the bilayer membrane in which they were studied. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (External Review Draft)

    Science.gov (United States)

    The IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) was released for external peer review in June 2017. EPA’s Science Advisory Board’s (SAB) Chemical Assessment Advisory Committee (CAAC) will conduct a peer review of the scientific basis supporting the ETB...

  8. IRIS Health Assessment of 2,2',4,4'-Tetrabromodiphenyl Ether (BDE-47) CASRN 5436-43-12,2',4,4',5-Pentabromodiphenyl Ether (BDE-99) CASRN 60348-60-92,2',4,4',5,5'-Hexabromodiphenyl Ether (BDE-153) CASRN 68631-49-22,2',3,3',4,4',5,5',6,6'-Decabromodiphenyl Ether (BDE-209) CASRN 1163-19-5

    Science.gov (United States)

    Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in furniture foam (pentaBDE), plastics for TV cabinets, consumer electronics, wire insulation, and backcoatings for draperies and upholstery (decaBDE), and plastics for personal computers and small appliances (oc...

  9. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Public Comment Draft)

    Science.gov (United States)

    In September 2016, the U.S. Environmental Protection Agency's (USEPA) released the draft Integrated Risk Information System (IRIS) Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE). Consistent with the 2013 IRIS Enhancements, draft IRIS assessments are released prior to e...

  10. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (External Review Draft, 2009)

    Science.gov (United States)

    EPA is conducting a peer review and public comment of the scientific basis supporting the human health hazard and dose-response assessment of ethyl tertiary butyl ether (ETBE) that when finalized will appear on the Integrated Risk Information System (IRIS) database.

  11. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Interagency Science Consultation Draft)

    Science.gov (United States)

    In September 2016, EPA released the draft IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) for public comment and discussion. The draft assessment was reviewed internally by EPA and by other federal agencies and White House Offices before public release. Consistent ...

  12. [Determination of biphenyl ether herbicides in water using HPLC with cloud-point extraction].

    Science.gov (United States)

    He, Cheng-Yan; Li, Yuan-Qian; Wang, Shen-Jiao; Ouyang, Hua-Xue; Zheng, Bo

    2010-01-01

    To determine residues of multiple biphenyl ether herbicides simultaneously in water using high performance liquid chromatography (HPLC) with cloud-point extraction. The residues of eight biphenyl ether herbicides (including bentazone, fomesafen, acifluorfen, aclonifen, bifenox, fluoroglycofenethy, nitrofen, oxyfluorfen) in water samples were extracted with cloud-point extraction of Triton X-114. The analytes were separated and determined using reverse phase HPLC with ultraviolet detector at 300 nm. Optimized conditions for the pretreatment of water samples and the parameters of chromatographic separation applied. There was a good linear correlation between the concentration and the peak area of the analytes in the range of 0.05-2.00 mg/L (r = 0.9991-0.9998). Except bentazone, the spiked recoveries of the biphenyl ether herbicides in the water samples ranged from 80.1% to 100.9%, with relative standard deviations ranging from 2.70% to 6.40%. The detection limit of the method ranged from 0.10 microg/L to 0.50 microg/L. The proposed method is simple, rapid and sensitive, and can meet the requirements of determination of multiple biphenyl ether herbicides simultaneously in natural waters.

  13. Photosynthesis involvement in the mechanism of action of diphenyl ether herbicides.

    Science.gov (United States)

    Ensminger, M P; Hess, F D

    1985-05-01

    Photosynthesis is not required for the toxicity of diphenyl ether herbicides, nor are chloroplast thylakoids the primary site of diphenyl ether herbicide activity. Isolated spinach (Spinacia oleracea L.) chloroplast fragments produced malonyl dialdehyde, indicating lipid peroxidation, when paraquat (1,1'-dimethyl-4,4'-bipyridinium ion) or diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] were added to the medium, but no malonyl dialdehyde was produced when chloroplast fragments were treated with the methyl ester of acifluorfen (methyl 5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid), oxyfluorfen [2-chloro-1-(3-ethoxy-4-nitrophenoxy)-4-(trifluoromethyl)benzene], or MC15608 (methyl 5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-chlorobenzoate). In most cases the toxicity of acifluorfen-methyl, oxyfluorfen, or MC15608 to the unicellular green alga Chlamydomonas eugametos (Moewus) did not decrease after simultaneous treatment with diuron. However, diuron significantly reduced cell death after paraquat treatment at all but the highest paraquat concentration tested (0.1 millimolar). These data indicate electron transport of photosynthesis is not serving the same function for diphenyl ether herbicides as for paraquat. Additional evidence for differential action of paraquat was obtained from the superoxide scavenger copper penicillamine (copper complex of 2-amino-3-mercapto-3-methylbutanoic acid). Copper penicillamine eliminated paraquat toxicity in cucumber (Cucumis sativus L.) cotyledons but did not reduce diphenyl ether herbicide toxicity.

  14. Photosynthesis Involvement in the Mechanism of Action of Diphenyl Ether Herbicides 1

    Science.gov (United States)

    Ensminger, Michael P.; Hess, F. Dan

    1985-01-01

    Photosynthesis is not required for the toxicity of diphenyl ether herbicides, nor are chloroplast thylakoids the primary site of diphenyl ether herbicide activity. Isolated spinach (Spinacia oleracea L.) chloroplast fragments produced malonyl dialdehyde, indicating lipid peroxidation, when paraquat (1,1′-dimethyl-4,4′-bipyridinium ion) or diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] were added to the medium, but no malonyl dialdehyde was produced when chloroplast fragments were treated with the methyl ester of acifluorfen (methyl 5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid), oxyfluorfen [2-chloro-1-(3-ethoxy-4-nitrophenoxy)-4-(trifluoromethyl)benzene], or MC15608 (methyl 5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-chlorobenzoate). In most cases the toxicity of acifluorfen-methyl, oxyfluorfen, or MC15608 to the unicellular green alga Chlamydomonas eugametos (Moewus) did not decrease after simultaneous treatment with diuron. However, diuron significantly reduced cell death after paraquat treatment at all but the highest paraquat concentration tested (0.1 millimolar). These data indicate electron transport of photosynthesis is not serving the same function for diphenyl ether herbicides as for paraquat. Additional evidence for differential action of paraquat was obtained from the superoxide scavenger copper penicillamine (copper complex of 2-amino-3-mercapto-3-methylbutanoic acid). Copper penicillamine eliminated paraquat toxicity in cucumber (Cucumis sativus L.) cotyledons but did not reduce diphenyl ether herbicide toxicity. PMID:16664206

  15. Enhanced diisobutene production in the presence of methyl tertiary butyl ether

    Science.gov (United States)

    Smith, L.A. Jr.

    1983-03-01

    In the liquid phase reaction of isobutene in the presence of resin cation exchange resins with itself in a C[sub 4] hydrocarbon stream to form dimers, the formation of higher polymers, oligomers, and co-dimer by-products is suppressed by the presence of 0.0001 to 1 mole per mole of isobutene of methyl tertiary butyl ether. 1 fig.

  16. The PROMETHEE multiple criteria decision making analysis for selecting the best membrane prepared from sulfonated poly(ether ketone)s and poly(ether sulfone)s for proton exchange membrane fuel cell

    International Nuclear Information System (INIS)

    Nikouei, Mohammad Ali; Oroujzadeh, Maryam; Mehdipour-Ataei, Shahram

    2017-01-01

    Proton exchange membrane as the heart of fuel cell has been the topic of many research activities in recent years. Finding a suitable alternative for Nafion membranes is one of the most important issues of interest. This study is dedicated to sulfonated poly(ether ketone) and poly(ether sulfone) membranes. For synthesis of these two groups of polymers, two different isomeric biphenols (meta- and para-) were used and each group of membranes with three different degree of sulfonation (25, 35, and 45%) was synthesized. In this way, twelve different membrane samples were obtained and their properties were evaluated. Since each membrane had some strong and some weak points of properties in comparison to the other ones, using a rational analysis for choosing the best membrane between prepared samples was inevitable. For this purpose a PROMETHEE based multiple criteria decision making approach was applied and for evaluation of the weight of each criterion, Shannon entropy method was used. Final results showed that poly(ether ketone) membranes in selected criteria were better than poly(ether sulfone) membranes and as expected, membranes with the highest degree of sulfonation (45%) were placed at the top ranking levels. - Highlights: • Sulfonated poly(ether ketone)s and Poly(ether sulfone)s were synthesized. • Related membranes for PEMFC were prepared. • The properties of membranes were measured. • Multiple criteria decision making approach was used to ranking the membranes. • PROMETHEE based approach selected poly(ether ketone)s as better choices.

  17. Selective crystallization of cations with crown ethers; Selektive Kristallisation von Kationen mit Kronenethern

    Energy Technology Data Exchange (ETDEWEB)

    Heffels, Dennis Egidius

    2014-07-04

    The aim of this work was to study the selectivity and preferences of the incorporation of differently sized cations in the cavities of various crown ethers and the characterization of the resulting compounds. The coordination preferences of crown ethers with different cavities have long been known, and the impact of other effects on the structure formation have increasingly become the focus of attention. In this work a comparative overview of the coordination preferences depending on various factors was undertaken. The focus was mainly on the variation of the cavity of the crown ether in the presence of differently sized cations. In addition, the effects of the solvent and differently coordinating anions have been investigated. Within the framework of this work, basic coordination preferences could be detected with rare earth nitrates, which are affected particularly by the choice of the solvent. The formation of different types of structures could be controlled by varying the conditions such that the incorporation of the cation in the cavity of the crown ether was influenced and the formation of a particular type of structure can be influenced partly by the choice of solvent. In this case no direct preferences for the incorporation into the cavity of the crown ether in relation to the cation size were observed for rare earth cations. However, the coordination of the crown ether leads in each case - for lanthanides - to rather high coordination numbers. A total of five new rare earth complexes and two structural variants could be observed with crown ethers. In the study of the selectivity of the incorporation into the cavity, known structures were also reproduced and further structures were characterized but the crystal structures not entirely solved. With the use of monovalent cations such as potassium, lithium or silver a total of nine new compounds could be synthesized, while no clear preferences for the incorporation of certain cations were detected. The

  18. Assessment of ether and alcohol fuels from coal. Volume 2. Technical report

    Energy Technology Data Exchange (ETDEWEB)

    1983-03-01

    A unique route for the indirect liquefaction of coal to produce transportation fuel has been evaluated. The resultant fuel includes alkyl tertiary alkyl ethers and higher alcohols, all in the gasoline boiling range. When blended into gasoline, the ether fuel provides several advantages over the lower alcohols: (1) lower chemical oxygen content, (2) less-severe water-separation problems, and (3) reduced front-end volatility effects. The ether fuel also has high-octane quality. Further, it can be utilized as a gasoline substitute in all proportions. Production of ether fuel combines several steps, all of which are or have been practiced on an industrial scale: (1) coal gasification, (2) gas cleanup and shift to desired H/sub 2/:CO ratio, (3) conversion of synthesis gas to isobutanol, methanol, and higher alcohols, (4) separation of alcohols, (5) chemical dehydration of isobutanol to isobutylene, and (6) etherification of isobutylene with methanol. A pilot-plant investigation of the isobutanol synthesis step was performed. Estimates of ether-fuel manufacturing costs indicate this process route is significantly more costly than synthesis of methanol. However, the fuel performance features provide incentive for developing the necessary process and catalyst improvements. Co-production of higher-molecular-weight co-solvent alcohols represents a less-drastic form of methanol modification to achieve improvement in the performance of methanol-gasoline blends. Costs were estimated for producing several proportions of methanol plus higher alcohols from coal. Estimated fuel selling price increases regularly but modestly with higher alcohol content.

  19. EDTA excess Zn(II) back-titration in the presence of 4-(2-pyridylazo)-resorcinol indicator and naphthol green {beta} as inert dye for determining Cr(III) as Cr(III)/EDTA complex: Application of the method to a leather industry wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Venezia, M.; Alonzo, G. [Dipartimento di Ingegneria e Tecnologie Agro Forestali, Universita degli Studi di Palermo, Viale delle Scienze, 90128 Palermo (Italy); Palmisano, L. [Dipartimento di Ingegneria Chimica dei Processi e dei Materiali, Universita degli Studi di Palermo, Viale delle Scienze, 90128 Palermo (Italy)], E-mail: palmisano@dicpm.unipa.it

    2008-03-01

    The colour changes of 4-(2-pyridylazo)-resorcinol and naphthol green {beta} as new screening metallochromic indicator in back-titration of EDTA excess with Zn(II) to determine Cr(III)/EDTA complex was investigated with the help of tristimulus colorimetry. Specific colour discrimination (SCD) and L*, a*, b* 1976 parameters were successfully applied to evaluate the quality of colour transition at the end-point in non-alkaline media and in the presence of Zn(II) and Ca(II) which resulted in non-interfering species at 1 x 10{sup -3} M and 2 x 10{sup -3} M, respectively. The above concentrations are comparable with those used for Cr(III). Validation of the fast and accurate reported method was performed by atomic absorption spectroscopy. Moreover, the method was applied for determining Cr as Cr(III) in a wastewater effluent deriving from a leather industry.

  20. EDTA excess Zn(II) back-titration in the presence of 4-(2-pyridylazo)-resorcinol indicator and naphthol green β as inert dye for determining Cr(III) as Cr(III)/EDTA complex: Application of the method to a leather industry wastewater

    International Nuclear Information System (INIS)

    Venezia, M.; Alonzo, G.; Palmisano, L.

    2008-01-01

    The colour changes of 4-(2-pyridylazo)-resorcinol and naphthol green β as new screening metallochromic indicator in back-titration of EDTA excess with Zn(II) to determine Cr(III)/EDTA complex was investigated with the help of tristimulus colorimetry. Specific colour discrimination (SCD) and L*, a*, b* 1976 parameters were successfully applied to evaluate the quality of colour transition at the end-point in non-alkaline media and in the presence of Zn(II) and Ca(II) which resulted in non-interfering species at 1 x 10 -3 M and 2 x 10 -3 M, respectively. The above concentrations are comparable with those used for Cr(III). Validation of the fast and accurate reported method was performed by atomic absorption spectroscopy. Moreover, the method was applied for determining Cr as Cr(III) in a wastewater effluent deriving from a leather industry