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Sample records for butyl ether ester

  1. TERATOLOGY AND POSTNATAL STUDIES IN RATS OF THE PROPYLENE GLYCOL BUTYL ETHER AND ISOOCTYL ESTERS OF 2,4-DICHLOROPHENOXYACETIC ACID

    Science.gov (United States)

    The purpose of this study was to evaluate the teratogenic potential of the propylene glycol butyl ether (PGBE) and isooctyl (IO) esters of 2,4-dichlorophenoxyacetic acid (2,4-D). Accordingly, groups of pregnant CD rats received daily oral doses of PGBE or IO equivalent to 0, 6.25...

  2. Sublethal and acute toxicity of the ethylene glycol butyl ether ester formulation of triclopyr to juvenile coho salmon (Oncorhynchus kisutch).

    Science.gov (United States)

    Johansen, J A; Geen, G H

    1990-01-01

    The toxicity of Garlon4, the ethylene glycol butyl ether ester formulation of the herbicide tryclopyr, to juvenile coho salmon (Oncorhynchus kisutch) was investigated at several lethal and sublethal concentrations. Fish behavior, random activity and oxygen uptake were monitored. Coho salmon exhibited three distinct responses related to concentration and duration of exposure: (1) at concentrations greater than 0.56 mg/L fish were initially lethargic, then regressed to a highly distressed condition characterized by elevated oxygen uptake and finally death, (2) at 0.32-0.43 mg/L fish were lethargic throughout the exposure period with reduced oxygen uptake, and (3) at concentrations less than or equal to 0.10 mg/L fish were hypersensitive to stimuli, exhibiting elevated activity and oxygen uptake levels during photoperiod transitions. Whole body residue analysis showed that uptake of the ester and subsequent hydrolysis to the acid form in the fish was rapid, with significant accumulation of the acid in the tissues. This suggests that some threshold tissue concentrations were associated with the observed results. For juvenile coho salmon the 96-hr LC50 of Garlon4 was 0.84 mg/L. PMID:2386416

  3. Effect of Parameters on Oxychlorination of Tert-Butyl Ethers

    OpenAIRE

    Gaca, Jerzy; Gackowska, Alicja; Belt, Natalia

    2008-01-01

    The effect of concentration, molar ratios of reagents, pH, and temperature on formation of chloro-organic products in reaction of tert-butyl ethers with chloride ions and hydrogen peroxide has been determined. A significant effect of Cl− ions and H2O2 molar ratios on the rate of chloro-organic product formation has been observed. Studies on oxychlorination of tert-butylethyl ether (ETBE) at pH 7, 3.5, and 2.5 have been carried out. It was found that introduction of hydronium ions into the rea...

  4. Methyltert-butyl Ether (MTBE) Degradation by a Microbial Consortium

    OpenAIRE

    S. B. Mortazavi; A Nikpey; A. Rezaee; H Asilian; A Khavanin; H. Kazemian

    2005-01-01

    Methyl tert-butyl ether (MTBE) is added to reformulated gasoline to meet the 1990 Clean Air Act directives. Widespread use of MTBE in gasoline has resulted in groundwater contamination. Because of its undesirable effects on drinking water and ecologically harmful effects, MTBE removal has become a public health and environmental concern. In this study, we have isolated a mixed bacterial culture which is capable of degrading the MTBE as a sole carbon and energy source. This consortium was deve...

  5. 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.

  6. Review of glycol ether and glycol ether ester solvents used in the coating industry.

    OpenAIRE

    Smith, R.L.

    1984-01-01

    Ethylene oxide-based glycol ether and glycol ether ester solvents have been used in the coatings industry for the past fifty years. Because of their excellent performance properties (evaporation rate, blush resistance, flow-out and leveling properties, solubility for coating resins, solvent activity, mild odor, good coupling ability, good solvent release) a complete line of ethylene oxide-based solvents of various molecular weights has been developed. These glycol ether and glycol ether ester...

  7. Methyltert-butyl Ether (MTBE Degradation by a Microbial Consortium

    Directory of Open Access Journals (Sweden)

    S. B. Mortazavi

    2005-01-01

    Full Text Available Methyl tert-butyl ether (MTBE is added to reformulated gasoline to meet the 1990 Clean Air Act directives. Widespread use of MTBE in gasoline has resulted in groundwater contamination. Because of its undesirable effects on drinking water and ecologically harmful effects, MTBE removal has become a public health and environmental concern. In this study, we have isolated a mixed bacterial culture which is capable of degrading the MTBE as a sole carbon and energy source. This consortium was developed from mixed urban and petrochemical activated sludge after 4 month's enrichment. Enrichment was conducted in batch reactor, fitted with a screw cap and butyl rubber septum. MTBE concentration was measured in head space by gas chromatography. Degradation was determined by MTBE removal. MTBE biodegradation was depended to Dissolved Oxygen (DO concentration and not affected by the changes in concentration of trace element solution or other stimulator Substances. Degradation rates were nearly 1.478 mg MTBE h-1 g-1 (wet biomass and didn't change with MTBE concentration (up 500 mg L-1.

  8. IRIS Toxicological Review of Ethylene Glycol Mono-Butyl Ether (EGBE) (Interagency Science Discussion Draft)

    Science.gov (United States)

    EPA is releasing 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 Assessme...

  9. An efficient and highly selective ortho-tert-butylation of p-cresol with methyl tert-butyl ether catalyzed by sulfonated ionic liquids

    Directory of Open Access Journals (Sweden)

    Alamdari Reza Fareghi

    2014-01-01

    Full Text Available A novel series of sulfonic acid-functionalized ionic liquids (SFILs was found to act as efficient catalysts for ortho-tert-butylation of p-cresol with methyl tert-butyl ether (MTBE as the tert-butylating agent without an added solvent. The mono o-tert-butylated product was obtained in up to 80.4% isolated yield and 95.2% selectivity under such green conditions. No O-tert-butylated byproducts were formed.

  10. An efficient and highly selective ortho-tert-butylation of p-cresol with methyl tert-butyl ether catalyzed by sulfonated ionic liquids

    OpenAIRE

    Alamdari Reza Fareghi; Zamani Faezeh Ghorbani; Zekri Negar

    2014-01-01

    A novel series of sulfonic acid-functionalized ionic liquids (SFILs) was found to act as efficient catalysts for ortho-tert-butylation of p-cresol with methyl tert-butyl ether (MTBE) as the tert-butylating agent without an added solvent. The mono o-tert-butylated product was obtained in up to 80.4% isolated yield and 95.2% selectivity under such green conditions. No O-tert-butylated byproducts were formed.

  11. AN EVALUATION OF THE HUMAN CARCINOGENIC POTENTIAL OF ETHYLENE GLYCOL BUTYL ETHER: INTERIM FINAL POSITION PAPER

    Science.gov (United States)

    In order to determine the merit of a petition to remove ethylene glycol ether (EGBE) from the Agency's Hazardous Air Pollutant (HAP) list, EPA has developed an interim final position paper, An Evaluation of the Human Carcinogenic Potential of Ethylene Glycol Butyl Ether, t...

  12. 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.

  13. Selective enzymatic hydrolysis of C-terminal tert-butyl esters of peptides

    OpenAIRE

    Eggen, I.F.; Boeriu, C.G.

    2007-01-01

    The present invention relates to a process for the selective enzymatic hydrolysis of C-terminal esters of peptide substrates in the synthesis of peptides, comprising hydrolysing C-terminal tert-butyl esters using the protease subtilisin. This process is useful in the production of protected or unprotected peptides.

  14. Selective enzymatic hydrolysis of C-terminal tert-butyl esters of peptides

    NARCIS (Netherlands)

    Eggen, I.F.; Boeriu, C.G.

    2007-01-01

    The present invention relates to a process for the selective enzymatic hydrolysis of C-terminal esters of peptide substrates in the synthesis of peptides, comprising hydrolysing C-terminal tert-butyl esters using the protease subtilisin. This process is useful in the production of protected or unpro

  15. Laboratory Method for Analysis of Small Concentrations of Methyl tert-Butyl Ether and Other Ether Gasoline Oxygenates in Water

    Science.gov (United States)

    Rose, Donna L.; Connor, Brooke F.; Abney, Sonja R.; Raese, Jon W.

    1998-01-01

    This Fact Sheet presents data for analysis of nanogram-per-liter concentrations of methyl tert-butyl ether (MTBE) and three other ether gasoline oxygenates, including methyl tert-pentyl ether (TAME), diisopropyl ether (DIPE), and ethyl tert-butyl ether (ETBE), by purge- and-trap capillary-column gas chromatography. Long-term method detection levels (LT-MDLs) for MTBE, TAME, DIPE, and ETBE ranged from 15 to 83 nanograms per liter (0.015 to 0.083 microgram per liter). Nanogram-per-liter-concentration detections are reported if all of the identification criteria are met, whereas previous methods censored detections at a pre-determined method reporting level. The reporting level for this method is defined as two times the LT-MDL, does not censor detections at less than this concentration, and is referred to as the nondetection value (NDV). Bias and variability data from multiple analyses, analysts, and instruments over a 60-day period show the oxygenate recoveries ranging from 100 to 109 percent, with 6 to 8 percent relative standard deviation. MTBE, TAME, DIPE, and ETBE were not detected in the analysis of 225 laboratory reagent blanks from January to December 1997. A preservation study in ground water and surface water indicates that all the oxygenates are stable at pH 2 for up to 216 days, with recoveries ranging from 94 to 115 percent on day 216, and relative standard deviations ranging from 5 to 9 percent for the duration of the study.

  16. INFLUENCE OF METHYL TERT-BUTYL ETHER (MTBE) ON LAKE WATER ALGAE

    Science.gov (United States)

    Methyl tert-butyl ether (MTBE) has been used as an octane booster in gasoline in the United States since the 1970s. MTBE use increased greatly in the 1990s with the implementation of the Clean Air Act Amendments of 1990. The MTBE enhanced a more complete combustion of fuel hydroc...

  17. Isothermal (vapor + liquid) equilibria and excess enthalpy data of {1-hexene + methyl butyl ether (MBE)} and {1-hexene + methyl tert-butyl ether (MTBE)} binary systems at several temperatures

    International Nuclear Information System (INIS)

    Highlights: ► Vapor pressures of (1-hexene + methyl butyl ether) or (1-hexene + methyl tert-butyl ether) are reported between (263 and 363) K. ► The two mixtures exhibit positive GE. ► Additionally, molar excess enthalpies, HE, for the two binary systems have been measured at 303.15. - Abstract: The vapor pressures of {1-hexene + methyl butyl ether (MBE)} and {1-hexene + methyl tert-butyl ether (MTBE)} binary mixtures and of the three pure components were measured by means of a static device at temperatures between (263 and 333) K. The data were correlated with the Antoine equation. From these data, excess Gibbs functions were calculated for several constant temperatures and fitted to a third-order Redlich–Kister equation using the Barker’s method. Additionally, molar excess enthalpies, HE, for the two binary systems have been measured at 303.15 K using an isothermal flow calorimeter.

  18. Temperature influence on mixing properties of {ethyl tert-butyl ether (ETBE) + gasoline additives}

    International Nuclear Information System (INIS)

    The densities and ultrasonic velocity of {ethyl tert-butyl ether (ETBE) + (benzene, toluene, ethylbenzene, isooctane, tert-butyl alcohol, and ethanol)} over the temperature range (288.15 to 323.15) K and atmospheric pressure, have been measured over the whole concentration range. The experimental excess volumes and deviation of isentropic compressibilities data have been analysed in terms of different theoretical models. The gathered data improve open literature related to gasoline additives, and help to understand the ETBE volumetric and acoustic trend into different chemical environment

  19. A direct and sustainable synthesis of tertiary butyl esters enabled by flow microreactors.

    Science.gov (United States)

    Degennaro, Leonardo; Maggiulli, Daniela; Carlucci, Claudia; Fanelli, Flavio; Romanazzi, Giuseppe; Luisi, Renzo

    2016-08-01

    Tertiary butyl esters find large applications in synthetic organic chemistry. A straightforward method for the direct introduction of the tert-butoxycarbonyl group into a variety of organic compounds has been developed using flow microreactor systems. The resultant flow process was more efficient, versatile and sustainable compared to the batch. PMID:27383138

  20. Simultaneous clostridial fermentation, lipase-catalyzed esterification, and ester extraction to enrich diesel with butyl butyrate

    NARCIS (Netherlands)

    Berg, C. van den; Heeres, A.S.; Wielen, L.A.M. van der; Straathof, A.J.J.

    2013-01-01

    The recovery of 1-butanol from fermentation broth is energy-intensive since typical concentrations in fermentation broth are below 20gL -1. To prevent butanol inhibition and high downstream processing costs, we aimed at producing butyl esters instead of 1-butanol. It is shown that it is possible to

  1. Adsorption of Methyl Tertiary Butyl Ether on Granular Zeolites: Batch and Column Studies

    OpenAIRE

    Abu-Lail, Laila; Bergendahl, John A.; Thompson, Robert W

    2010-01-01

    Methyl tertiary butyl ether (MTBE) has been shown to be readily removed from water with powdered zeolites, but the passage of water through fixed beds of very small powdered zeolites produces high friction losses not encountered in flow through larger sized granular materials. In this study, equilibrium and kinetic adsorption of MTBE onto granular zeolites, a coconut shell granular activated carbon (CS-1240), and a commercial carbon adsorbent (CCA) sample was evaluated. In addition, the effec...

  2. Determination of low level methyl tert-butyl ether, ethyl tert-butyl ether and methyl tert-amyl ether in human urine by HS-SPME gas chromatography/mass spectrometry

    International Nuclear Information System (INIS)

    Methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE) and tert-amyl methyl ether (TAME) are oxygenated compounds added to gasoline to enhance octane rating and to improve combustion. They may be found as pollutants of living and working environments. In this work a robotized method for the quantification of low level MTBE, ETBE and TAME in human urine was developed and validated. The analytes were sampled in the headspace of urine by SPME in the presence of MTBE-d12 as internal standard. Different fibers were compared for their linearity and extraction efficiency: carboxen/polydimethylsiloxane, polydimethylsiloxane/divinylbenzene, and polydimethylsiloxane. The first, although highly efficient, was discarded due to deviation of linearity for competitive displacement, and the polydimethylsiloxane/divinylbenzene fiber was chosen instead. The analysis was performed by GC/MS operating in the electron impact mode. The method is very specific, with range of linearity 30-4600 ng L-1, within- and between-run precision, as coefficient of variation, -1 for all the analytes. The influence of the matrix on the quantification of these ethers was evaluated analysing the specimens of seven traffic policemen exposed to autovehicular emissions: using the calibration curve and the method of standard additions comparable levels of MTBE (68-528 ng L-1), ETBE (-1), and TAME (-1) were obtained

  3. 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. PMID:23673223

  4. Enhancement of methyl tert-butyl ether degradation by the addition of readily metabolizable organic substrates

    International Nuclear Information System (INIS)

    Supplements with readily metabolizable organic substrates were investigated to increase the biomass and enhance degradation of methyl tert-butyl ether (MTBE) due to the low biomass yield of MTBE which has been one of the factors for low-rate MTBE degradation. The influence of various organic substrates on the rate of aerobic degradation of methyl tert-butyl ether (MTBE) by Methylibium petroleiphilum PM1 was investigated, and only yeast extract (YE), beef extract and tryptone exhibited stimulatory effect. With the concentration of each substrate being 100 mg/L, the average MTBE removal rate could increase to 1.29, 1.20 and 1.04 mg/(L h), respectively, in comparison with 0.71 mg/(L h) when carried out in medium without addition. The stimulatory effects of YE addition, as well as induction period required by MTBE degradation, varied dramatically with the storage conditions, pre-culture medium and concentrations of the inoculums. The extent of stimulatory effects of YE might be closely related to the proportion of induction period in the total time of MTBE-degradation. The removal efficiency increased from about 50% to 90.5% with the addition of YE in a packed-bed reactor loaded with calcium alginate immobilized cells.

  5. 40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

    Science.gov (United States)

    2010-07-01

    ... polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether. 721.1729 Section 721.1729 Protection... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene......

  6. Synthesis and intrinsic blue fluorescence study of hyperbranched poly(ester-amide-ether)

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A series of hyperbranched poly(ester-amide-ether)s (H-PEAEs) were synthesized via the A2+CB3 approach by the self-transesterification of ethyl ester-amide-ethers end-capped with three hydroxyl groups and ethyl ester group at two terminals.The molecular structures were characterized with 1H NMR and FT-IR spectroscopy.The number average molecular weights were estimated by GPC analysis to possess bimodal wide distribution from 1.57 to 2.09.The strong inherent blue fluorescence was observed at 330 nm for excitation and 390 nm for emission.Moreover,the emission intensity and fluorescence quantum yield increased along with the incorporated ether chain length,as well as almost linearly with the H-PEAE concentration in an aqueous solution.For comparing the fluorescence performance,the linear poly(ester-amide-ether) (L-PEAE) and hyperbranched poly(ester-amide) (H-PEA) were synthesized.The results showed that the coexistence of ether bond and carboxyl group in the molecular chain was essential for generating the strong fluorescence.However,the compact backbone of H-PEAE would be propitious to the enhancement of fluorescence properties.

  7. Determination of low level methyl tert-butyl ether, ethyl tert-butyl ether and methyl tert-amyl ether in human urine by HS-SPME gas chromatography/mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Scibetta, Licia [Department of Occupational and Environmental Medicine, University of Milano and Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Via S. Barnaba, 8-20122 Milan (Italy); Campo, Laura [Department of Occupational and Environmental Medicine, University of Milano and Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Via S. Barnaba, 8-20122 Milan (Italy); Mercadante, Rosa [Department of Occupational and Environmental Medicine, University of Milano and Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Via S. Barnaba, 8-20122 Milan (Italy); Foa, Vito [Department of Occupational and Environmental Medicine, University of Milano and Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Via S. Barnaba, 8-20122 Milan (Italy); Fustinoni, Silvia [Department of Occupational and Environmental Medicine, University of Milano and Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Via S. Barnaba, 8-20122 Milan (Italy)]. E-mail: silvia.fustinoni@unimi.it

    2007-01-02

    Methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE) and tert-amyl methyl ether (TAME) are oxygenated compounds added to gasoline to enhance octane rating and to improve combustion. They may be found as pollutants of living and working environments. In this work a robotized method for the quantification of low level MTBE, ETBE and TAME in human urine was developed and validated. The analytes were sampled in the headspace of urine by SPME in the presence of MTBE-d12 as internal standard. Different fibers were compared for their linearity and extraction efficiency: carboxen/polydimethylsiloxane, polydimethylsiloxane/divinylbenzene, and polydimethylsiloxane. The first, although highly efficient, was discarded due to deviation of linearity for competitive displacement, and the polydimethylsiloxane/divinylbenzene fiber was chosen instead. The analysis was performed by GC/MS operating in the electron impact mode. The method is very specific, with range of linearity 30-4600 ng L{sup -1}, within- and between-run precision, as coefficient of variation, <22 and <16%, accuracy within 20% the theoretical level, and limit of detection of 6 ng L{sup -1} for all the analytes. The influence of the matrix on the quantification of these ethers was evaluated analysing the specimens of seven traffic policemen exposed to autovehicular emissions: using the calibration curve and the method of standard additions comparable levels of MTBE (68-528 ng L{sup -1}), ETBE (<6 ng L{sup -1}), and TAME (<6 ng L{sup -1}) were obtained.

  8. INTERACTION OF METHYL-TERT BUTYL ETHER AND WATER STRESS ON SEED GERMINATION AND SEEDLING GROWTH IN SOIL MICROCOSMS

    Science.gov (United States)

    Methyl tert-butyl ether (MTBE) is a widespread contaminant in surface and ground water in the United States. Frequently irrigation is used to water fields to germinate planted seeds and sustain plant growth. A likely possibility exists that water used may have some MTBE. Our s...

  9. Estimation of the fraction of biologically active methyl tert-butyl ether degraders in a heterogeneous biomass sample

    DEFF Research Database (Denmark)

    Waul, Christopher Kevin; Arvin, Erik; Schmidt, Jens Ejbye

    2008-01-01

    bed reactor, was determined using a batch kinetic based approach. The procedure involved modeling of methyl tert-butyl ether removal rates from batch experiments followed by parameter estimations. It was estimated to be 5-14% (w/w) of the measured volatile suspended solids concentration in the reactor....

  10. Draft Genome Sequence of Paenibacillus etheri sp. nov. SH7T, a Methyl Tert-Butyl Ether Degrader.

    Science.gov (United States)

    Purswani, Jessica; Guisado, Isabel M; Gonzalez-Lopez, Jesus; Pozo, Clementina

    2016-01-01

    We report here the draft genome sequence of Paenibacillus etheri sp. nov. SH7(T) (= CECT 8558(T) = DSM 29760(T)), isolated from a hydrocarbon-contaminated soil pilot plant in Granada, Spain. The bacterium was isolated and sequenced due to its methyl tert-butyl ether (MTBE)-degrading properties. PMID:26893420

  11. Impacts of Ethanol on Anaerobic Production of Tert-Butyl Alcohol (TBA) from Methyl Tert-Butyl Ether (MTBE) in Groundwater

    OpenAIRE

    Scow, K M; MacKay, Douglas

    2008-01-01

    Methyl tert-butyl ether (MTBE) is a contaminant of concern to groundwater resources due to its persistence in subsurface environments. MTBE appears to be degraded readily in the presence of oxygen but is recalcitrant under the anaerobic conditions prevalent in the subsurface, and can be converted into the more toxic compound tert-butanol (TBA). As ethanol is being promoted as a renewable fuel and a replacement for MTBE in gasoline formulations, its potential impact on the biodegradation of pr...

  12. STUDY ON THE SYNTHESIS AND PROPERTIES OF POLY(ESTER-IMIDE-ETHER) MULTIBLOCK COPOLYMERS

    Institute of Scientific and Technical Information of China (English)

    Zu-yao Shan; Zhen-yi Li

    2000-01-01

    A new class of poly(ester-imide-ether) multiblock copolymers was synthesized by transes-terification and melt copolymerization of dimethyl terephthalate (DMT) and N-(4-carbomethoxyphenyl)-4-(carbomethoxy)-phthalimide with ethylene glycol (EG) and polytetramethylene glycol (PTMG). The structure of the above copolymers was characterized by 1H-NMR and IR spectroscopy. Some properties of the coplymers were also examined. It was found that their mechanical properties and heat stability, compared with poly(ether-ester) copolymers, were obviously improved.

  13. Catalytic Synthesis of Glycerol tert-Butyl Ethers as Fuel Additives from the Biodiesel By-Product Glycerol

    Directory of Open Access Journals (Sweden)

    Rui Huang

    2015-01-01

    Full Text Available Glycerol is a major by-product in the biodiesel production process. Every 100 kg of biodiesel produced generates approximately 10 kg of crude glycerol. As the biodiesel industry has expanded rapidly in recent years, finding new uses of the excess crude glycerol is important. Many studies have examined alternative uses of crude glycerol. One of them is the use of glycerol derivatives, such as glycerol tert-butyl ethers as fuel additives. In this paper, the etherification kinetics of glycerol with tert-butyl alcohol to glycerol tert-butyl ethers was studied using an Amberlyst catalyst. The influences of the catalyst type and loading, reaction time, molar ratio, and temperature were investigated in detail.

  14. Isolation and Initial Characterization of A Pure Cultures Capable to Degradation Methyl tert- Butyl Ether (MTBE

    Directory of Open Access Journals (Sweden)

    A Nikpey

    2006-07-01

    Full Text Available Methyl tert-butyl ether (MTBE, a gasoline octane enhancer, was introduced as a substitute for lead tetraethyl over 30 years ago. Widespread use of MTBE in gasoline, has introduced MTBE into the environment compartments, mostly into the under ground and surface water and water as a second most frequently detected contaminant. In this study, we have isolated pure cultures from bacterial consortium capable to use MTBE as a sole carbon and energy source. MTBE biodegradation rate was measured in headspace by gas chromatography. Initial liner rates of biodegradation by Pinpoint and white strains were found 2.9 mg and 3 mg MTBE hˉ1 gˉ1 wet biomass, respectively. The results of 16S rDNA PCR disclosed similarities in the banding patterns between the cultures, and the known degrading strain PM1. The results of this study suggest promising perspectives for engineering the in situ bioremediation of MTBE.

  15. Degradation of aqueous methyl tert-butyl ether by photochemical, biological, and their combined processes

    Directory of Open Access Journals (Sweden)

    Azadeh Asadi

    2006-01-01

    Full Text Available The degradation of aqueous methyl tert-butyl ether (MTBE at relatively high concentrations was investigated by various photo-induced oxidation processes such as UV/H2O2 and UV/TiO2 as well as biological processes and their combination. It was shown that the degradation of MTBE by UV/H2O2 and TiO2 photocatalytic followed a first-order model with apparent rate constant of 1.31×10−1 and 1.21×10−2 min-1, respectively. It was observed that UV/H2O2/TiO2 process did not have any advantages over each of the other processes alone. The biodegradation of methyl tert-butyl ether (MTBE was evaluated using aerobic mixed culture with three different approaches, including ultimate biological oxygen demand (BODU assessment, nonacclimated, and acclimated mixed cultures. The apparent rate constant for the biodegradation of MTBE by nonacclimated mixed culture was 4.36×10−2 day-1. It was shown that the acclimatization of the mixed cultures enhanced the rate of biodegradation of MTBE to 3.24×10−1mg L-1h-1. Finally, the effects of the photocatalytic pretreatment of aqueous MTBE on its subsequent biological treatment were studied. It was observed that the rate of bioreaction was not enhanced and the photocatalytic pretreatment had adverse effects on its biological treatment so that the apparent rate constant decreased to 2.83×10−1 mg L-1h-1.

  16. Removal of Methyl Tert-Butyl Ether (MTBE from Contaminated Water by Photocatalytic Process

    Directory of Open Access Journals (Sweden)

    A Eslami

    2009-06-01

    Full Text Available "nBackground: Methyl tert-butyl ether (MTBE has been commercially used as an octane enhancer to replace tetraethyl lead in gasoline since 1979. The high mobility, water solubility, and resistance to natural attenuation associated with MTBE may re­sult in contamination of ground and surface waters. In this investigation the degradation of aqueous MTBE at relatively high concentrations was studied by UV-vis/TiO2/O2 photocatalytic process. The effect of important operational parameters such as pH, oxygen flow, catalyst loading, and irradiation time were also studied."nMethods:Concentration of MTBE and intermediates such as tert-butyl formate (TBF and tert-butyl alcohol (TBA were meas­ured using a gas chromatograph equipped with flam ionization detector and combined with headspace sampler."nResults: The time required for complete degradation increased from 15 to 150 min, when the initial concentration was in­creased from 10 to 500 mg/L. The first order rate constant for degradation of MTBE from the hydroxyl radical was esti­mated to be 0.266 to 0.033 min-1 as the concentration increased from 10 to 500 mg/L. Study on the overall mineralization moni­tored by total organic carbon (TOC analysis showed that in the initial concentration of 100 mg/L MTBE, complete min­eralization was obtained after 110 min under UV-vis/TiO2/O2 photocatalytic process."nConclusion: The data presented in this paper clearly indicate that UV/TiO2/O2 advanced oxidation process provides an effi­cient treatment alternative for the remediation of MTBE contaminated water.  

  17. Degradation of a recalcitrant xenobiotic compound: methyl tert-butyl ether (MTBE) metabolism by mycobacterium austroafricanum; Degradation d'un compose xenobiotique recalcitrant: metabolisme du methyl tert-butyl ether (MTBE) par mycobacterium austroafricanum IFP 2012

    Energy Technology Data Exchange (ETDEWEB)

    Francois, A.

    2002-11-01

    Methyl tert-butyl ether (MTBE) is introduced up to 15% (vol/vol) in gasoline in order to obtain a good octane number and to prevent carbon monoxide emissions. However, as a consequence of storage tanks leakage, MTBE became one of the major pollutants of aquifers because of its very low biodegradability. The present study aimed at investigating the biodegradation of MTBE by Mycobacterium austroafricanum IFP 2012. The MTBE metabolic pathway was partially elucidated owing to the identification of some intermediates (tert-butyl formate (TBF), tert-butyl alcohol (TBA), a-hydroxy-isobutyric acid and acetone) and some enzymatic activities (MTBE/TBA monooxygenase (non hemic and inducible), TBF esterase, 2-propanol: NDMA oxidoreductase and another monooxygenase involved in acetone degradation). The involvement of TBF and the requirement of cobalt could be explanations for the low natural attenuation of MTBE; whereas the methoxy group does not seem to be implicated. (author)

  18. Subchronic exposure to ethyl tertiary butyl ether resulting in genetic damage in Aldh2 knockout mice.

    Science.gov (United States)

    Weng, Zuquan; Suda, Megumi; Ohtani, Katsumi; Mei, Nan; Kawamoto, Toshihiro; Nakajima, Tamie; Wang, Rui-Sheng

    2013-09-15

    Ethyl tertiary butyl ether (ETBE) is biofuel additive recently used in Japan and some other countries. Limited evidence shows that ETBE has low toxicity. Acetaldehyde (AA), however, as one primary metabolite of ETBE, is clearly genotoxic and has been considered to be a potential carcinogen. The aim of this study was to evaluate the effects of ALDH2 gene on ETBE-induced genotoxicity and metabolism of its metabolites after inhalation exposure to ETBE. A group of wild-type (WT) and Aldh2 knockout (KO) C57BL/6 mice were exposed to 500ppm ETBE for 1-6h, and the blood concentrations of ETBE metabolites, including AA, tert-butyl alcohol and 2-methyl-1,2-propanediol, were measured. Another group of mice of WT and KO were exposed to 0, 500, 1750, or 5000ppm ETBE for 6h/day with 5 days per weeks for 13 weeks. Genotoxic effects of ETBE in these mice were measured by the alkaline comet assay, 8-hydroxyguanine DNA-glycosylase modified comet assay and micronucleus test. With short-term exposure to ETBE, the blood concentrations of all the three metabolites in KO mice were significantly higher than the corresponding concentrations of those in WT mice of both sexes. After subchronic exposure to ETBE, there was significant increase in DNA damage in a dose-dependent manner in KO male mice, while only 5000ppm exposure significantly increased DNA damage in male WT mice. Overall, there was a significant sex difference in genetic damage in both genetic types of mice. These results showed that ALDH2 is involved in the detoxification of ETBE and lack of enzyme activity may greatly increase the sensitivity to the genotoxic effects of ETBE, and male mice were more sensitive than females. PMID:23810710

  19. Anaerobic Methyl tert-Butyl Ether-Degrading Microorganisms Identified in Wastewater Treatment Plant Samples by Stable Isotope Probing

    OpenAIRE

    Sun, Weimin; Sun, Xiaoxu; Cupples, Alison M.

    2012-01-01

    Anaerobic methyl tert-butyl ether (MTBE) degradation potential was investigated in samples from a range of sources. From these 22 experimental variations, only one source (from wastewater treatment plant samples) exhibited MTBE degradation. These microcosms were methanogenic and were subjected to DNA-based stable isotope probing (SIP) targeted to both bacteria and archaea to identify the putative MTBE degraders. For this purpose, DNA was extracted at two time points, subjected to ultracentrif...

  20. Methyl tert-butyl ether biodegradation by indigenous aquifer microorganisms under natural and artificial oxic conditions.

    Science.gov (United States)

    Landmeyer, J E; Chapelle, F H; Herlong, H H; Bradley, P M

    2001-03-15

    Microbial communities indigenous to a shallow groundwater system near Beaufort, SC, degraded milligram per liter concentrations of methyl tert-butyl ether (MTBE) under natural and artificial oxic conditions. Significant MTBE biodegradation was observed where anoxic, MTBE-contaminated groundwater discharged to a concrete-lined ditch. In the anoxic groundwater adjacent to the ditch, concentrations of MTBE were > 1 mg/L. Where groundwater discharge occurs, dissolved oxygen (DO) concentrations beneath the ditch exceeded 1.0 mg/Lto a depth of 1.5 m, and MTBE concentrations decreased to CO2 in laboratory liquid culture studies, with no accumulation of intermediate compounds. Upgradient of the ditch in the anoxic, MTBE- and BTEX-contaminated aquifer, addition of a soluble oxygen release compound resulted in oxic conditions and rapid MTBE biodegradation by indigenous microorganisms. In an observation well located closest to the oxygen addition area, DO concentrations increased from 0.4 to 12 mg/L in <60 days and MTBE concentrations decreased from 20 to 3 mg/L. In the same time period at a downgradient observation well, DO increased from <0.2 to 2 mg/L and MTBE concentrations decreased from 30 to <5 mg/L. These results indicate that microorganisms indigenous to the groundwater system at this site can degrade milligram per liter concentrations of MTBE under natural and artificial oxic conditions. PMID:11347923

  1. Ethyl-tertiary-butyl-ether (ETBE) as an aviation fuel: Eleventh international symposium on alcohol fuels

    Energy Technology Data Exchange (ETDEWEB)

    Maben, G.D.; Shauck, M.E.; Zanin, M.G.

    1996-12-31

    This paper discusses the preliminary flight testing of an aircraft using neat burning ethyl-tertiary-butyl-ether (ETBE) as a fuel. No additional changes were made to the fuel delivery systems which had previously been modified to provide the higher fuel flow rates required to operate the engine on neat ethanol. Air-fuel ratios were manually adjusted with the mixture control. This system allows the pilot to adjust the mixture to compensate for changes in air density caused by altitude, pressure and temperature. The engine was instrumented to measure exhaust gas temperatures (EGT), cylinder head temperatures (CHT), and fuel flows, while the standard aircraft instruments were used to collect aircraft performance data. Baseline engine data for ETBE and Avgas are compared. Preliminary data indicates the technical and economic feasibility of using ETBE as an aviation fuel for the piston engine fleet. Furthermore, the energy density of ETBE qualifies it as a candidate for a turbine engine fuel of which 16.2 billion gallons are used in the US each year.

  2. Toxicity of methyl tertiary-butyl ether on human blood lymphocytes.

    Science.gov (United States)

    Salimi, Ahmad; Vaghar-Moussavi, Mehrdad; Seydi, Enayatollah; Pourahmad, Jalal

    2016-05-01

    Methyl tertiary-butyl ether (MTBE) is a synthetic solvent widely used as oxygenate in unleaded gasoline. Few studies have addressed the cellular toxicity of MTBE on some cell lines, and so far, no comprehensive study has been conducted to investigate the probable immunotoxicity of this compound. In this study, the toxicity of MTBE on human blood lymphocytes was evaluated. Blood lymphocytes were isolated from healthy male volunteers' blood, using Ficoll polysaccharide followed by gradient centrifugation. Cell viability, reactive oxygen species (ROS) formation, lipid peroxidation, glutathione levels, and damage to mitochondria and lysosome were determined in blood lymphocytes after 6-h incubation with different concentrations of MTBE (0.1, 0.5, 1, and 2 mM). Our results showed that MTBE, in particular, decreased cell viability, which was associated with significant increase at intracellular ROS level and toxic alterations in mitochondria and lysosomes in human blood lymphocytes. Moreover, it was shown that MTBE strongly provoked lipid peroxidation and also depleted glutathione level at higher concentrations. Interestingly, MTBE exhibited its cytotoxic effects at low concentrations that may resemble to its concentrations in human blood following occupational and environmental exposure. It is therefore concluded that MTBE was capable of inducing oxidative stress and damage to mitochondria and lysosomes in human lymphocytes at concentrations ranging from 5 to 40 μg/L, which may be present in human blood as a result of environmental exposure. PMID:26797945

  3. MORPHOLOGY AND PROPERTIES OF SEGMENTED BLOCK COPOLY (ETHER ESTER)S FIBERS MADE BY GEL-DRAWING

    Institute of Scientific and Technical Information of China (English)

    CHEN Shouxi; G.Wegner

    1988-01-01

    The segmented block copoly(ether ester)s were swollen by tetrahydrofuran (THF) at 60℃ and formed-fibers by gel-drawing. The morphology and properties of these fibers were investigated by optical and electron microscopes, X-ray diffraction, DSC and an Instron test machine. The band structure morphology was observed in the gel-drawing fibers. The molecular chains were highly oriented as proved by X-ray diffraction data. The results indicated that the gel-drawing fibers have much better mechanical properties than those obtained otherwise. The tensile strength and elastic modulus were found to be 280 MPa and 802 MPa, repsectively. The mechanism of the gel-drawing process was also discussed.

  4. Exposure to methyl tert-butyl ether and benzene among service station attendants and operators.

    Science.gov (United States)

    Hartle, R

    1993-12-01

    Concerns for atmospheric pollution from auto exhaust have led to the blending of "oxygenates" with motor fuels. The most common oxygenate, methyl tert-butyl ether (MTBE) is currently required within several metropolitan areas (Denver and Phoenix) in the range of 12% of the motor fuel. Amendments to the Clean Air Act may expand this requirement to as many as 44 other areas of the United States in the near future. In consideration of the magnitude of potential uncontrolled exposures from its extensive use and a related concern involving the potential influence of MTBE blending on exposures to other constituents of gasoline (particularly benzene), an evaluation of exposures among service station attendants and operators was undertaken at the request, and in cooperation with, the American Petroleum Institute during the latter part of 1990. For application of the survey results to a broad audience, three categories or types of service stations were identified with regard to MTBE use and exposure potential: a) service stations that do not use MTBE or use it only as an octane enhancer, b) service stations with seasonal requirements to use 12-15% MTBE (the Denver, Colorado, and Phoenix, Arizona, metropolitan areas), and c) service stations equipped with stage II (active) vapor recovery systems (several coastal areas, most notably Southern California). At the two sampled service stations that use only minimal amounts of MTBE (less than 1%), only 1 of 32 personal breathing zone (PBZ) samples from attendants was above the analytical limit of detection, reported at 0.16 ppm. The geometric mean concentration of benzene among this same population (n = 32) was 0.04 ppm.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8020445

  5. Combined toxicities of methyl tert-butyl ether and its metabolite tert-butyl alcohol on earthworms via different exposure routes.

    Science.gov (United States)

    Lee, Woo-Mi; Yoon, Youngdae; An, Youn-Joo

    2015-06-01

    Methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) are among the major soil contaminants that threaten the health of soil ecosystems. Many MTBE-contaminated sites accumulate TBA, because TBA is the intermediate of MTBE biodegradation. To access the risk of MTBE and TBA in soil, we investigated the combined toxicities of MTBE and TBA using two earthworm species, Perionyx excavatus and Eisenia andrei, as well as the toxic effects via different exposure routes. The combined toxicity showed weak antagonistic effects (LC50mix values were slightly greater than 1.0), and sensitivity toward same pollutants differed in the two earthworm species. Moreover, the toxicity of MTBE and TBA was also affected by the exposure route; both filter paper and artificial soil tests showed that dermal-only exposure to MTBE had an even greater toxic effect than combined dermal and oral exposure. Thus, we suggest that diverse environmental factors including organic materials, the physicochemical properties of the contact media, and the exposure routes of the organism, should be taken into consideration when assessing the effects of pollutants on organisms in diverse environmental systems. PMID:25706436

  6. Methyl tert-butyl ether (MTBE) in urban and rural precipitation in Germany

    Energy Technology Data Exchange (ETDEWEB)

    Achten, C.; Kolb, A.; Puettmann, W. [J.W. Goethe-Universitaet Frankfurt am Main (Germany). Institut fuer Mineralogie-Umweltanalytik

    2001-07-01

    The use of the oxygenate methyl tert-butyl ether (MTBE) in gasoline has led to detectable concentrations in urban and rural air up to 160ppbV. Results from MTBE measurement in precipitation have not been reported so far. In the present study, 120 samples of precipitation collected at 17 sampling locations all over Germany have been analyzed for their MTBE content. Analysis is performed by a combination of headspace-solid-phase microextraction (HS-SPME) and gas chromatography/mass spectrometry (GC-MS). A 75{mu}m poly(dimethylsiloxane)/Carboxene fiber and a cryostat is used for SPME. The detection limit is 10ng/l. In precipitation samples, MTBE was detected in wintertimes only with a maximum concentration of 85ng/l. Measurement at Frankfurt/M City from 6 September 2000 to 12 March 2001 provided for 49% of the data concentrations in the range of 30-85ng/1 (n=17). Sampling in winter 2000/2001 at several German cities and rural locations showed that MTBE is more often detectable in urban (86%, n=78) than in rural (18%,n=42) precipitation. By comparing the results with corresponding temperatures and amounts of precipitation it can be concluded that the detection of MTBE in urban precipitation is observed at ambient temperatures lower than about 10-15{sup o}C. Moreover, the first precipitation after a dry period accumulates more MTBE than precipitation during or at the end of a wet period (wash-out effect). Highest concentrations occurred in snow samples. Corresponding mean air equilibrium concentrations of 0.04ppbV (urban samples) and 0.0lppbV (rural samples) are calculated. This is about one magnitude lower than year round and summertime measurements in the US and in Switzerland. Urban runoff (n=12) and corresponding precipitation sampling indicate that urban runoff might be composed of about 20% MTBE that is already transported by air and precipitation, whereas about 80% may be attributed to direct uptake of vehicle emissions and leakage near the road during

  7. [Methyl tert-butyl ether (MTBE) in atmosphere of the Pearl River Delta, China].

    Science.gov (United States)

    Wang, Bo-guang; Shao, Min; Zhang, Yuan-hang; Lü, Wan-Ming; Zhou, Yan

    2007-07-01

    The concentration of methyl tert-butyl ether (MTBE) and its spatio-temporal distribution were researched in atmosphere of the Pearl River Delta (PRD) by sampling with air sampling canisters and analyzing with pre-concentrator and gas chromatograph-mass spectrum instrument. The results showed that 1) MTBE could be prevalently checked in atmosphere of traffic area, industrial area, residential area and commercial area of the PRD, and its range of hourly average concentration in the long-term observation was from 0 - 1.250 microg m(-3), the summer had more serious pollution than the spring, and urban was the central area of high MTBE concentration, and suburban in the downwind was obviously polluted by the urban air. 2) During the enhanced observation in summertime, the diurnal average concentration of Guangzhou urban site was (1.520 +/- 0.370) microg m(-3), which was about 7 times of Huadou site in the downwind of Guangzhou and over 100 times of Conghua site in the background of Guangzhou. In urban, 2 peak values appeared in the period of 10:00 - 12:00 and 16:00 - 18:00 respectively, and the nighttime had the lowest average concentration, but the suburban in the downwind had the peak value in the nighttime. 3) During the enhanced observation in wintertime, the diurnal average concentration of Guangzhou urban site was (0.950 +/- 0.240) microg m(-3), which was 3.6 times of Xinken site in the downwind of Guangzhou. Several peak values appeared on the diurnal variation, the high concentration period of urban was in 18:00 - 22:00, and that of suburban was in 04:00 - 10:00 of the next day. 4) When it was weak sunshine, the concentration of MTBE beside the urban traffic roadside was decreasing with the height increasing, but when it was strong sunshine, it was increasing with the height increasing. So, except the original emission from the automobiles, MTBE still had the secondary pollution sources formed by air photochemical reaction. PMID:17891978

  8. Experimental Analysis and Energetic Evaluation for Mahua Oil Methyl Ester with Diethyl Ether

    Directory of Open Access Journals (Sweden)

    Bhanu Pratap SINGH

    2014-11-01

    Full Text Available A theoretical method based on various existing process models has been developed for the performance evaluation of a compression ignition engine by using diesel and Mahua oil as an input fuel. Experimental evaluations of Mahua oil methyl ester/diesel along with diethyl ether were tested on a single cylinder naturally-aspirated indirect-injection diesel engine. The purpose of using diethyl ether with diesel/biodiesel is to control the emission from the diesel engine and to improve its performance. The effect of test fuels at different volumetric proportion and loads are also analyzed on the engine performance and emission. The comparisons of theoretical and experimental results are discussed. Engine performance characteristics predicted by this model are in closer approximation to that of experimental results. Engineering equation solver has been used to validate the model with the experimental results.

  9. More about Interactions of Rhodamine 19 Butyl Ester with Rat Liver Mitochondria.

    Science.gov (United States)

    Rogov, A G; Trendeleva, T A; Aliverdieva, D A; Zvyagilskaya, R A

    2016-04-01

    Oxidative stress is one of the major factors underlying mitochondrial dysfunctions. One of the most promising approaches for alleviating or preventing oxidative stress is the use of cationic uncouplers that accumulate in mitochondria in accordance to the level of the membrane potential, producing "mild" uncoupling. Based on this theoretical background, cationic rhodamine 19 butyl ester (C4R1) was synthesized and tested within the framework of the research project guided by V. P. Skulachev. The results of these tests were presented (Khailova et al. (2014) Biochim. Biophys. Acta, 1837, 1739-1747), but one publication could not accommodate all data on interactions of C4R1 with isolated mitochondria. In addition to previously presented data, we found that the effect of C4R1 on the rate of oxygen uptake is subject to temporal variations, which probably reflects variable rates of C4R1 entry into the mitochondria. Consequently, transient stimulation of respiration can be followed by inhibition. C4R1 was found not to shunt electron flow from complex I of the respiratory chain; it largely acted as an inhibitor of complex I in the respiratory chain and showed antioxidant activity. C4R1 taken at low, non-uncoupling concentrations enhanced the uncoupling activity of fatty acids (e.g. palmitate). Relatively low C4R1 concentrations stimulated opening of a nonspecific Ca2+/Pi-dependent pore. ATP synthesis and hydrolysis were substantially inhibited by C4R1 at low concentrations that had no appreciable effects on respiration in states 4 and 3 and only slightly decreased the membrane potential. Besides, conditions were revealed allowing correct evaluation of the membrane potential generated at the inner mitochondrial membrane with safranin O upon oxidation of both succinate and NAD-dependent substrates in the presence of C4R1. PMID:27293102

  10. Computer-assisted automated synthesis. III. Synthesis of substituted N-(carboxyalkyl) amino-acid tert-butyl ester derivatives.

    Science.gov (United States)

    Hayashi, N; Sugawara, T; Kato, S

    1991-01-01

    A versatile automated synthesis apparatus, equipped with a chemical artificial intelligence, was developed to prepare and isolate a wide variety of compounds. The apparatus was to the synthesis of substituted N-(carboxyalkyl)amino-acids. The apparatus [1,2] is composed of units for performing various tasks,for example reagent supply, reaction, purification and separation, each linked to a control system. All synthetic processes, including washing and drying of the apparatus after each synthetic run, were automatically performed from the mixing of the reactants to the isolation of the products as powders or crystals. The reaction of an amino-acid tertbutyl ester acetic acid salt with a 2-keto acid sodium salt produces an unstable intermediate, Schiff base, which is reduced with sodum cyanoborohydride to give a substituted N-(carboxyalkyl)aminoacid tert-butyl ester sodium salt. The equilibrium and the consecutive reactions were controlled by adding sodium cyanoborohydride using the artificial intelligence software, which contained novel kinetic equations [3] and substituent effects [4].Substitued N-(carboxyalkyl)amino-acid tert-butyl esters, 90 derivatives, were automatically synthesized using the computerassisted automated synthesis apparatus. The syntheses were performed unattended 24 hours a day, except for supplying the raw materials, reagents and solvents. The apparatus is extremely valuable for synthesizing many derivatives of a particular compound. The configurations of the products were determined by circular dichroism measurements. PMID:18924904

  11. Characterization of the Initial Reactions during the Cometabolic Oxidation of Methyl tert-Butyl Ether by Propane-Grown Mycobacterium vaccae JOB5

    OpenAIRE

    Smith, Christy A.; O'Reilly, Kirk T.; Hyman, Michael R.

    2003-01-01

    The initial reactions in the cometabolic oxidation of the gasoline oxygenate, methyl tert-butyl ether (MTBE), by Mycobacterium vaccae JOB5 have been characterized. Two products, tert-butyl formate (TBF) and tert-butyl alcohol (TBA), rapidly accumulated extracellularly when propane-grown cells were incubated with MTBE. Lower rates of TBF and TBA production from MTBE were also observed with cells grown on 1- or 2-propanol, while neither product was generated from MTBE by cells grown on casein-y...

  12. Experimental Analysis of Performance of Diesel Engine Using Kusum Methyl Ester With Diethyl Ether as Additive

    Directory of Open Access Journals (Sweden)

    Sandip S. Jawre,

    2014-05-01

    Full Text Available The fossile fuels are widely used in diesel engine and continually depleting with increasing consumption and prices day by day. The fatty acid methyl ester has become an effective alternative to diesel. Various types of vegetable oil such as Jatropha, karanja, cottonseed, neem, sunflower, palm, mahuva, coconut etc. can be used as fuel in diesel engine. Kusum oil is one of the fuel used in present work. The viscosity of kusum oil is very high, so it was reduced by Transesterification process. This study presents effect of diethyl ether as additive to biodiesel of kusum (schliechera oleosa methyl ester on the performance and emission of diesel engine at different load and constant speed and two different injection pressure (170 and 190 bar. From literature it was observed that very few studies had been conducted on use of neat biodiesel and diethyl ether blends and use of kusum methyl ester (KME in diesel engine found to be very less as compared to different biodiesel. Hence this topic was taken under study. The fuels and its blends used are 100% diesel, B100 (100% KME, BD-1 (95% KME, 5% DEE, BD-2 (90% KME, 10% DEE, BD-3 (85% KME, 15% DEE respectively. It was observed that the performance of engine increases at high injection pres-sure. The results indicate that lower BSFC was observed with BD-3 as compared to B100, BD-1 and BD-2. Brake thermal efficiency of BD-3 decreased at 170 bar injection pressure but it increase at 190 bar. Drastic re-duction in smoke is observed with all blends at higher engine loads. DEE addition to biodiesel reflects better engine performance compared to neat biodiesel.

  13. Evaluating UV/H2O2 processes for methyl tert-butyl ether and tertiary butyl alcohol removal: effect of pretreatment options and light sources.

    Science.gov (United States)

    Li, Ke; Hokanson, David R; Crittenden, John C; Trussell, Rhodes R; Minakata, Daisuke

    2008-12-01

    In this paper, we evaluate the efficiency of UV/H2O2 process to remove methyl tert-butyl ether (MtBE) and tertiary butyl alcohol (tBA) from a drinking water source. Kinetic models were used to evaluate the removal efficiency of the UV/H2O2 technologies with different pretreatment options and light sources. Two commercial UV light sources, i.e. low pressure, high intensity lamps and medium pressure, high intensity lamps, were evaluated. The following pretreatment alternatives were evaluated: (1) ion exchange softening with seawater regeneration (NaIX); (2) Pellet Softening; (3) weak acid ion exchange (WAIX); and (4) high pH lime softening followed by reverse osmosis (RO). The presence or absence of a dealkalization step prior to the UV/H2O2 Advanced Oxidation Process (AOP) was also evaluated for each pretreatment possibility. Pretreatment has a significant impact on the performance of UV/H2O2 process. The NaIX with dealkalization was shown to be the most cost effective. The electrical energy per order (EEO) values for MtBE and tBA using low pressure high output UV lamps (LPUV) and 10mg/LH2O2 are 0.77 and 3.0 kWh/kgal-order, or 0.20 and 0.79 kWh/m3-order, respectively. For medium pressure UV high output lamps (MPUV), EEO values for MtBE and tBA are 4.6 and 15 kWh/kgal-order, or 1.2 and 4.0 kWh/m3-order, for the same H2O2 dosage. PMID:18951605

  14. 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.

  15. Pulse radiolysis study of reactions of alkyl and alkylperoxy radicals originating from methyl tert-butyl ether in the gas phase

    DEFF Research Database (Denmark)

    Langer, S.; Ljungström, E.; Ellermann, T.;

    1995-01-01

    UV spectra and kinetics for the reactions of alkyl and alkylperoxy radicals from methyl tert-butyl ether (MTBE) were studied in 1 atm of SF6 by the pulse radiolysis-UV absorption technique. UV spectra for the radical mixtures were quantified from 215 to 340 nm. At 240 nm, sigma(R) = (2.6 +/- 0.4) X...

  16. Pulse radiolysis study of reactions of alkyl and alkylperoxy radicals originating from methyl tert-butyl ether in the gas phase

    DEFF Research Database (Denmark)

    Langer, S.; Ljungström, E.; Ellermann, T.; Nielsen, O.J.; Sehested, J.

    UV spectra and kinetics for the reactions of alkyl and alkylperoxy radicals from methyl tert-butyl ether (MTBE) were studied in 1 atm of SF6 by the pulse radiolysis-UV absorption technique. UV spectra for the radical mixtures were quantified from 215 to 340 nm. At 240 nm, sigma(R) = (2.6 +/- 0.4) X...

  17. Solubility of anthracene in binary alkane + methyl tert-butyl ether solvent mixtures at 298.15 K

    Energy Technology Data Exchange (ETDEWEB)

    McHale, M.E.R.; Kauppila, A.S.M.; Acree, W.E. Jr. [Univ. of North Texas, Denton, TX (United States). Dept. of Chemistry

    1996-09-01

    Experimental solubilities are reported for anthracene dissolved in seven binary mixtures containing methyl tert-butyl ether (also called 2-methoxy-2-methylpropane) with hexane, heptane, octane, cyclohexane, methylcyclohexane, 2,2,4-trimethylpentane, and tert-butylcyclohexane (also called (1,1-dimethylethyl)-cyclohexane) at 25 C. Results of these measurements are used to test two mathematical representations based upon the combined nearly ideal binary solvent (NIBS)/Redlich-Kister equation and modified Wilson model. For the seven systems studied, both equations were found to provide an accurate mathematical representation of the experimental data, with an overall average absolute deviation between measured and calculated values being on the order of 0.5%.

  18. UV absorption spectra and kinetics for alkyl and alkyl peroxy radicals originating from di-tert-butyl ether

    DEFF Research Database (Denmark)

    Nielsen, O.J.; Sehested, J.; Langer, S.; Ljungström, E.; Wängberg, I.

    Alkyl, (CH3)(3)COC(CH3)(2)CH2, and alkyl peroxy, (CH3)(3)COC(CH3)(2)CH2O2, radicals from di-tert-butyl ether (DTBE), have been studied in the gas phase at 296 K. A pulse radiolysis UV absorption technique was used to measure the spectra and kinetics. Absorption cross sections were quantified over......) s(-1) was found. The rate constants for the reaction of the alkyl peroxy radicals with NO and NO2 were determined to be (1.8 +/- 0.2) X 10(-12) and (9.9 +/- 1.3) X 10(-12) cm(3) molecule(-1) s(-1), respectively. As a part of the work the rate constants k(F + DTBE) and k(OH + DTBE) were determined to...

  19. Biological Activity of Methyl tert-butyl Ether in Relation to Soil Microorganisms has a Negative Environmental Impact

    Directory of Open Access Journals (Sweden)

    Gholam H.S. Bonjar

    2005-01-01

    Full Text Available Fuel oxygenates are added to gasoline to enhance combustion efficiency of automobiles and reduce air pollution. Methyl tert-butyl ether (MTBE is the most commonly used oxygenate because of its low cost, high-octane level and ease of blending with gasoline. However, due to its water solubility, high mobility and low biodegradability it leaches in soil subsurface at the speed of groundwater. Amending gasoline with MTBE has made a widespread contamination of groundwater, surface waters in coastal environments and at low levels in well water. Although current public concern about MTBE contamination is widely discussed, but its adverse effects on soil micro flora is not yet understood. Soil Streptomycetes are beneficial to soil productivity and are of the major contributors to the biological buffering of soils having antagonistic activity against wide spectrum of pathogenic bacteria and fungi. Streptomyceticidal activity of Methyl tert-butyl ether (MTBE is being reported here. Adverse effect of MTBE against four soil-inhabitant Streptomyces spp. isolates and two plant root-pathogens was investigated. To elucidate antimicrobial activity of MTBE, it was tested against four soil isolates of Streptomyces; a plant bacterial-pathogen, Erwinia carotovora and a plant root fungal-pathogen, Fusarium solani. MTBE did not reveal any growth inhibitory-activity against E. carotovora and F. solani but showed strong inhibitory effect against Streptomyces spp. isolates. The Minimum Inhibitory Concentration (MIC was 1/800 of the original MTBE. Fuel leaks and spills can adversely suppress or eliminate the Streptomyces role in the soil causing alteration in the balance of soil micro flora. This change will lead to domination of microorganisms with adverse biological or ecological effects. Fortunately, major oil companies have decided to phase out MTBE from automobile fuels because of its adverse effect on environment and human health.

  20. Study on Protective Clothing against SARS Using PTFE/Poly(ether-ester) Membrane

    Institute of Scientific and Technical Information of China (English)

    HAO Xin-min; ZHANG Jian-chun; GUO Yu-hai

    2004-01-01

    By means of texturing with organic conductive fiber, and then being treated with JAM-Y1 anti-bacteria agent, in the end, treated with the XL-550 waterproof agent, the PET fabric has permanent antistatic, anti-bacteria and waterproof and anti-oil properties. The PET fabric was laminated with PTFE membrane by paste dot coating, and then coated by Poly(ether-ester) solution in a direct process. The filter efficiency of NaCl aerosol, penetration property of poliomyelitis virus in liquid and animalcule in air of PET fabric laminated with PTFE membrane are measured. The properties show that the PET fabric laminated with PTFE membrane can separate SARS virus in air and liquid. The protective mechanism is also discussed in the article.

  1. HEAT-RESISTANT PYRIDINE-BASED POLY(ETHER-ESTER)S: SYNTHESIS,CHARACTERIZATION AND PROPERTIES

    Institute of Scientific and Technical Information of China (English)

    Shahram Mehdipour-Ataei; Ali Mahmoodi

    2013-01-01

    A pyridine-based diacid was synthesized via nucleophilic substitution reaction of 4-hydroxy benzoic acid with 2,6-dichloropyridine in the presence of potassium carbonate.The diacid was characterized using FT-IR and 1H-NMR spectroscopic methods and also with elemental analysis.Polycondensation reaction of the diacid with different diols including 1,4-dihydroxy benzene,1,5-dihydroxy naphthalene,bis-phenol A and bis-phenol-P resulted in preparation of pyridine-based poly(ether-ester)s.The polymers were characterized and their physical and thermal properties including inherent viscosity,molecular weight,solubility,thermal stability,thermal behavior and crystallinity were studied.They revealed high heat-resistance and improved solubility in polar solvents.Structure-property relations for the prepared polyester were also studied.

  2. Mono-, di-, and tri- tert-butyl ethers of glycerol . A molecular spectroscopic study

    Science.gov (United States)

    Jamróz, Małgorzata E.; Jarosz, Małgorzata; Witowska-Jarosz, Janina; Bednarek, Elżbieta; Tęcza, Witold; Jamróz, Michał H.; Dobrowolski, Jan Cz.; Kijeński, Jacek

    2007-07-01

    MS, NMR, IR and Raman molecular spectroscopy techniques were applied to characterize 3- tert-butoxy-propane-1,2-diol, 1,3-di- tert-butoxy-propan-2-ol, and 1,2,3-tri- tert-butoxy-propane. These ethers are the main products of glycerol etherification reaction and are excellent oxygen additives for diesel fuel. Computational DFT/ B3LYP/6-31G ** studies were performed to support and rationalize both vibrational spectroscopy analysis and the isomer ratio.

  3. Cometabolism of Methyl tertiary Butyl Ether and Gaseous n-Alkanes by Pseudomonas mendocina KR-1 Grown on C5 to C8 n-Alkanes

    OpenAIRE

    Smith, Christy A.; O'Reilly, Kirk T.; Hyman, Michael R.

    2003-01-01

    Pseudomonas mendocina KR-1 grew well on toluene, n-alkanes (C5 to C8), and 1° alcohols (C2 to C8) but not on other aromatics, gaseous n-alkanes (C1 to C4), isoalkanes (C4 to C6), 2° alcohols (C3 to C8), methyl tertiary butyl ether (MTBE), or tertiary butyl alcohol (TBA). Cells grown under carbon-limited conditions on n-alkanes in the presence of MTBE (42 μmol) oxidized up to 94% of the added MTBE to TBA. Less than 3% of the added MTBE was oxidized to TBA when cells were grown on either 1° alc...

  4. Measurement of methyl tert-butyl ether and tert-butyl alcohol in human blood by purge-and-trap gas chromatography-mass spectrometry using an isotope-dilution method.

    Science.gov (United States)

    Bonin, M A; Ashley, D L; Cardinali, F L; McCraw, J M; Wooten, J V

    1995-01-01

    We developed an isotope-dilution method for measuring methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) in whole human blood using a purge-and-trap gas chromatographic-mass spectrometric method. The labeled analogues for MTBE and TBA were [2H12]methyl tert-butyl ether and [2H9]-tert-butyl alcohol, respectively. Volatiles were removed from the blood by direct helium purging of the liquid; were trapped on a Tenax trap; and were desorbed, cryofocused, and chromatographed on a DB-624 capillary column that was connected directly to the ion source of a mass spectrometer. Detection was by mass analysis using a double-focusing magnetic-sector mass spectrometer operating in the full-scan mode at the medium mass resolution of 3000. For the isotope-dilution method, the minimum detection limits in blood (5-10 mL) are 0.01 microgram/L for MTBE and 0.06 microgram/L for TBA. The isotope-dilution method proved to be a big improvement in recovery, reproducibility, and sensitivity over our previous analytical method, which used the labeled ketone, [4-2H3]-2-butanone, as the internal standard for both MTBE and TBA. The isotope-dilution method has sufficient sensitivity for monitoring blood levels of MTBE and TBA in populations exposed to oxygenated fuels containing MTBE. PMID:7564298

  5. Study of an aquifer contaminated by ethyl tert-butyl ether (ETBE): Site characterization and on-site bioremediation

    International Nuclear Information System (INIS)

    Highlights: ► Ethyl tert-butyl ether (ETBE) (>300 mg L−1) found in a groundwater (gas-station). ► No significant carbon or hydrogen isotopic fractionation of ETBE along the plume. ► MC-IFP culture degraded ETBE (0.91 mg L−1 h−1) and BTEX (0.64 mg L−1 h−1). ► A pilot plant (2 m3) inoculated with MC-IFP degraded ETBE in groundwater (15 °C). ► ethB gene (ETBE biodegradation) amplified during bioaugmentation (5 × 106ethB gene copies L−1). - Abstract: Ethyl tert-butyl ether (ETBE) was detected at high concentration (300 mg L−1) in the groundwater below a gas-station. No significant carbon neither hydrogen isotopic fractionation of ETBE was detected along the plume. ETBE and BTEX biodegradation capacities of the indigenous microflora Pz1-ETBE and of a culture (MC-IFP) composed of Rhodococcus wratislaviensis IFP 2016, Rhodococcus aetherivorans IFP 2017 and Aquincola tertiaricarbonis IFP 2003 showed that ETBE and BTEX degradation rates were in the same range (ETBE: 0.91 and 0.83 mg L−1 h−1 and BTEX: 0.64 and 0.82 mg L−1 h−1, respectively) but tert-butanol (TBA) accumulated transiently at a high level using Pz1-ETBE (74 mg L−1). An on-site pilot plant (2 m3) filled with polluted groundwater and inoculated by MC-IFP, successfully degraded four successive additions of ETBE and gasoline. However, an insignificant ETBE isotopic fractionation was also accompanying this decrease which suggested the involvement of low fractionating-strains using EthB enzymes, but required of additional proofs. The ethB gene encoding a cytochrome P450 involved in ETBE biodegradation (present in R. aetherivorans IFP 2017) was monitored by quantitative real-time polymerase chain reaction (q-PCR) on DNA extracted from water sampled in the pilot plant which yield up to 5 × 106 copies of ethB gene per L−1.

  6. Study of an aquifer contaminated by ethyl tert-butyl ether (ETBE): Site characterization and on-site bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Fayolle-Guichard, Francoise, E-mail: francoise.fayolle@ifpen.fr [IFP Energies nouvelles, 1 et 4 avenue de Bois-Preau, 92852 Rueil-Malmaison (France); Durand, Jonathan [Institut EGID Bordeaux 3, 1 Allee Daguin 33607 Pessac Cedex (France); SERPOL, 2 chemin du Genie, BP 80, 69633 Venissieux Cedex (France); Cheucle, Mathilde [SERPOL, 2 chemin du Genie, BP 80, 69633 Venissieux Cedex (France); Rosell, Monica [Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, 04318 Leipzig (Germany); Michelland, Rory Julien [Universite de Lyon, F-69622 Lyon (France); Universite Lyon 1, Villeurbanne (France); CNRS, UMR5557, Ecologie Microbienne (France); Tracol, Jean-Philippe [SERPOL, 2 chemin du Genie, BP 80, 69633 Venissieux Cedex (France); Le Roux, Francoise [IFP Energies nouvelles, 1 et 4 avenue de Bois-Preau, 92852 Rueil-Malmaison (France); Grundman, Genevieve [Universite de Lyon, F-69622 Lyon (France); Universite Lyon 1, Villeurbanne (France); CNRS, UMR5557, Ecologie Microbienne (France); Atteia, Olivier [Institut EGID Bordeaux 3, 1 Allee Daguin 33607 Pessac Cedex (France); Richnow, Hans H. [Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, 04318 Leipzig (Germany); Dumestre, Alain [SERPOL, 2 chemin du Genie, BP 80, 69633 Venissieux Cedex (France); and others

    2012-01-30

    Highlights: Black-Right-Pointing-Pointer Ethyl tert-butyl ether (ETBE) (>300 mg L{sup -1}) found in a groundwater (gas-station). Black-Right-Pointing-Pointer No significant carbon or hydrogen isotopic fractionation of ETBE along the plume. Black-Right-Pointing-Pointer MC-IFP culture degraded ETBE (0.91 mg L{sup -1} h{sup -1}) and BTEX (0.64 mg L{sup -1} h{sup -1}). Black-Right-Pointing-Pointer A pilot plant (2 m{sup 3}) inoculated with MC-IFP degraded ETBE in groundwater (15 Degree-Sign C). Black-Right-Pointing-Pointer ethB gene (ETBE biodegradation) amplified during bioaugmentation (5 Multiplication-Sign 10{sup 6}ethB gene copies L{sup -1}). - Abstract: Ethyl tert-butyl ether (ETBE) was detected at high concentration (300 mg L{sup -1}) in the groundwater below a gas-station. No significant carbon neither hydrogen isotopic fractionation of ETBE was detected along the plume. ETBE and BTEX biodegradation capacities of the indigenous microflora Pz1-ETBE and of a culture (MC-IFP) composed of Rhodococcus wratislaviensis IFP 2016, Rhodococcus aetherivorans IFP 2017 and Aquincola tertiaricarbonis IFP 2003 showed that ETBE and BTEX degradation rates were in the same range (ETBE: 0.91 and 0.83 mg L{sup -1} h{sup -1} and BTEX: 0.64 and 0.82 mg L{sup -1} h{sup -1}, respectively) but tert-butanol (TBA) accumulated transiently at a high level using Pz1-ETBE (74 mg L{sup -1}). An on-site pilot plant (2 m{sup 3}) filled with polluted groundwater and inoculated by MC-IFP, successfully degraded four successive additions of ETBE and gasoline. However, an insignificant ETBE isotopic fractionation was also accompanying this decrease which suggested the involvement of low fractionating-strains using EthB enzymes, but required of additional proofs. The ethB gene encoding a cytochrome P450 involved in ETBE biodegradation (present in R. aetherivorans IFP 2017) was monitored by quantitative real-time polymerase chain reaction (q-PCR) on DNA extracted from water sampled in the pilot plant

  7. Reaction products and mechanisms for the reaction of n-butyl vinyl ether with the oxidants OH and Cl: Atmospheric implications

    Science.gov (United States)

    Colmenar, Inmaculada; Martín, Pilar; Cabañas, Beatriz; Salgado, Sagrario; Tapia, Araceli; Martínez, Ernesto

    2015-12-01

    A reaction product study for the degradation of butyl vinyl ether (CH3(CH2)3OCHdbnd CH2) by reaction with chlorine atoms (Cl) and hydroxyl radicals (OH) has been carried out using Fourier Transform Infrared absorption spectroscopy (FTIR) and/or Gas Chromatography-Mass Spectrometry with a Time of Flight analyzer (GC-TOFMS). The rate coefficient for the reaction of butyl vinyl ether (BVE) with chlorine atoms has also been evaluated for the first time at room temperature (298 ± 2) K and atmospheric pressure (708 ± 8) Torr. The rate coefficient obtained was (9.9 ± 1.5) × 10-10 cm3 molecule-1 s-1 and this indicates the high reactivity of butyl vinyl ether with Cl atoms. However, this value may be affected by the dark reaction of BVE with Cl2. The results of a qualitative study of the Cl reaction show that the main oxidation products are butyl formate (CH3(CH2)3OC(O)H), butyl chloroacetate (CH3(CH2)3OC(O)CH2Cl and formyl chloride (HCOCl). Individual yields in the ranges ∼16-40% and 30-70% in the absence and presence of NOx, respectively, have been estimated for these products. In the OH reaction, butyl formate and formic acid were identified as the main products, with yields of around 50 and 20%, respectively. Based on the results of this work and a literature survey, the addition of OH radicals and Cl atoms at the terminal C atom of the double bond in CH3(CH2)3OCHdbnd CH2 has been proposed as the first step in the reaction mechanism for both of the studied oxidants. The tropospheric lifetime of butyl vinyl ether is very short and, as a consequence, it will be rapidly degraded and will only be involved in tropospheric chemistry at a local level. The degradation products of these reactions should be considered when evaluating the atmospheric impact.

  8. Comparison of Biostimulation versus Bioaugmentation with Bacterial Strain PM1 for Treatment of Groundwater Contaminated with Methyl Tertiary Butyl Ether (MTBE)

    OpenAIRE

    Smith, Amanda E.; Hristova, Krassimira; Wood, Isaac; Mackay, Doug M.; Lory, Ernie; Lorenzana, Dale; Scow, Kate M.

    2004-01-01

    Widespread contamination of groundwater by methyl tertiary butyl ether (MTBE) has triggered the exploration of different technologies for in situ removal of the pollutant, including biostimulation of naturally occurring microbial communities or bioaugmentation with specific microbial strains known to biodegrade the oxygenate. After laboratory studies revealed that bacterial strain PM1 rapidly and completely biodegraded MTBE in groundwater sediments, the organism was tested in an in situ field...

  9. Controlled human exposure to methyl tertiary butyl ether in gasoline: symptoms, psychophysiologic and neurobehavioral responses of self-reported sensitive persons.

    OpenAIRE

    Fiedler, N; Kelly-McNeil, K; Mohr, S; Lehrer, P.; Opiekun, R E; Lee, C.(Institute of Physics, Academia Sinica, Taipei, Taiwan); Wainman, T; Hamer, R.; Weisel, C.; Edelberg, R; Lioy, P J

    2000-01-01

    The 1990 Clean Air Act mandated oxygenation of gasoline in regions where carbon monoxide standards were not met. To achieve this standard, methyl tertiary butyl ether (MTBE) was increased to 15% by volume during winter months in many locations. Subsequent to the increase of MTBE in gasoline, commuters reported increases in symptoms such as headache, nausea, and eye, nose, and throat irritation. The present study compared 12 individuals selected based on self-report of symptoms (self-reported ...

  10. Rotational Spectroscopy and Quantum Chemical Calculations of a Fruit Ester: the Microwave Spectrum of n-BUTYL Acetate

    Science.gov (United States)

    Attig, T.; Sutikdja, L. W.; Kannengiesser, R.; Stahl, W.; Kleiner, I.

    2013-06-01

    In the course of our studies on a number of aliphatic ester molecules and natural substances, the rotational spectrum of n-butyl acetate (CH_{3}-COO-C_4H_9) has been recorded for the first time in the 10-13.5 GHz frequency range, using the MB-FTMW spectrometer in Aachen, with an instrumental uncertainty of a few kHz for unblended lines. Three conformers were observed. The main conformer with C_{1} symmetry has a strong spectrum. The other two conformers have C_{s} and C_{1} symmetries. Their intensities are considerably weaker. The quantum chemical calculations of specific conformers were carried out at the MP2/6-311++G(d,p) level, and for the main conformer different levels of theory were calculated. To analyze the internal rotation of the acetyl methyl groups the codes XIAM (based on the Combined Axis Method) and BELGI (based on the Rho-Axis-Method) were used to model the large amplitude motion. The molecular structures of the three conformers were determined and the values of the experimental rotational constants were compared with those obtained by ab initio methods. For all conformers torsional barriers of approximately 100 cm^{-1} were found. This study is part of a larger project which aims at determining the lowest energy conformers and their structures of organic esters and ketones which are of interest for flavour or perfume synthetic applications. Project partly supported by the PHC PROCOPE 25059YB

  11. The impact of groundwater quality on the removal of methyl tertiary-butyl ether (MTBE) using advanced oxidation technology.

    Science.gov (United States)

    Tawabini, B; Fayad, N; Morsy, M

    2009-01-01

    In this study, the removal of methyl tertiary-butyl ether (MTBE) from contaminated groundwater using advanced oxidation technology was investigated. The UV/H(2)O(2) treatment process was applied to remove MTBE from two Saudi groundwater sources that have different quality characteristics with regard to their contents of inorganic species such as chloride, bromide, sulfates and alkalinity. MTBE was spiked into water samples collected from the two sources to a concentration level of about 250 microg/L. A 500 mL bench-scale forced-liquid circulation photoreactor was used to conduct the experiments. Two different UV lamps were utilized: 15 Watt low pressure (LP) and 150 Watt medium pressure (MP). Results of the study showed that the UV/H(2)O(2) process removed more than 90% of MTBE in 20 minutes when the MP lamp was used at an MTBE/H(2)O(2) molar ratio of 1:200. The results also showed that groundwater sources with higher levels of radical scavengers such as alkalinity, bromide, nitrate and sulfate showed lower rate of MTBE removal. PMID:19844063

  12. Study on Pervaporation Membranes for Removing Methanol from C5 or Methyl Tert—butyl Ether Mixtures

    Institute of Scientific and Technical Information of China (English)

    张林; 陈欢林; 周志军; 钱锦文; 高从Jie; 潘祖仁

    2003-01-01

    Several pervaporation membranes,cellulose acetate(CA),polyvinylbutyral(PVB),poly(MMA-co-AA),MMA-AA-BA,CA/PVB blend and CA/poly(MMA-co-AA)blend,were prepared,and their pervporation proper-ties were evaluated by separation of methanol/C5 or methanol/MTBE(methyl tert-butyl ether),The results shows that the CA composite membrane has a high separation performance (flux Jmethanol=35g.m-2.h-1 and separa-tion factor α>400)for methanol /C5 mixtures ,and the pervaporation characteristics of MMA-AA-BA copolymer membranes changes with the ratio of copolymer,For CA/poly(MMA-co-AA) blend membrane,the pervapora-tion performance is improved in comparison with CA or poly(MMA-co-AA) membrane,From the experiment of CA/PVB blend membranes for methanol/MTBE mixture,it is found that the compatibility of blends may affect the separation features of blend membrane.

  13. Health Risk Assessment for Inhalation Exposure to Methyl Tertiary Butyl Ether at Petrol Stations in Southern China

    Directory of Open Access Journals (Sweden)

    Dalin Hu

    2016-02-01

    Full Text Available Methyl tertiary butyl ether (MTBE, a well known gasoline additive, is used in China nationwide to enhance the octane number of gasoline and reduce harmful exhaust emissions, yet  little is known regarding the potential health risk associated with occupational exposure to MTBE in petrol stations. In this study, 97 petrol station attendants (PSAs in southern China were recruited for an assessment of the health risk associated with inhalation exposure to MTBE. The personal exposure levels of MTBE were analyzed by Head Space Solid Phase Microextraction GC/MS, and the demographic characteristics of the PSAs were investigated. Cancer and non-cancer risks were calculated with the methods recommended by the United States Environmental Protection Agency. The results showed that the exposure levels of MTBE in operating workers were much higher than among support staff (p < 0.01 and both were lower than 50 ppm (an occupational threshold limit value. The calculated cancer risks (CRs at the investigated petrol stations was 0.170 to 0.240 per 106 for operating workers, and 0.026 to 0.049 per 106 for support staff, which are below the typical target range for risk management of 1 × 10−6 to 1 × 10−4; The hazard quotients (HQs for all subjects were <1. In conclusion, our study indicates that the MTBE exposure of PSAs in southern China is in a low range which does not seem to be a significant health risk.

  14. Health Risk Assessment for Inhalation Exposure to Methyl Tertiary Butyl Ether at Petrol Stations in Southern China

    Science.gov (United States)

    Hu, Dalin; Yang, Jianping; Liu, Yungang; Zhang, Wenjuan; Peng, Xiaowu; Wei, Qinzhi; Yuan, Jianhui; Zhu, Zhiliang

    2016-01-01

    Methyl tertiary butyl ether (MTBE), a well known gasoline additive, is used in China nationwide to enhance the octane number of gasoline and reduce harmful exhaust emissions, yet  little is known regarding the potential health risk associated with occupational exposure to MTBE in petrol stations. In this study, 97 petrol station attendants (PSAs) in southern China were recruited for an assessment of the health risk associated with inhalation exposure to MTBE. The personal exposure levels of MTBE were analyzed by Head Space Solid Phase Microextraction GC/MS, and the demographic characteristics of the PSAs were investigated. Cancer and non-cancer risks were calculated with the methods recommended by the United States Environmental Protection Agency. The results showed that the exposure levels of MTBE in operating workers were much higher than among support staff (p < 0.01) and both were lower than 50 ppm (an occupational threshold limit value). The calculated cancer risks (CRs) at the investigated petrol stations was 0.170 to 0.240 per 106 for operating workers, and 0.026 to 0.049 per 106 for support staff, which are below the typical target range for risk management of 1 × 10−6 to 1 × 10−4; The hazard quotients (HQs) for all subjects were <1. In conclusion, our study indicates that the MTBE exposure of PSAs in southern China is in a low range which does not seem to be a significant health risk. PMID:26861375

  15. Assessing soil ecotoxicity of methyl tert-butyl ether using earthworm bioassay; closed soil microcosm test for volatile organic compounds

    International Nuclear Information System (INIS)

    An earthworm bioassay was conducted to assess ecotoxicity in methyl tert-butyl ether (MTBE)-amended soils. Ecotoxicity of MTBE to earthworms was evaluated by a paper contact method, natural field soil test, and an OECD artificial soil test. All tests were conducted in closed systems to prevent volatilization of MTBE out of test units. Test earthworm species were Perionyx excavatus and Eisenia andrei. Mortality and abnormal morphology of earthworms exposed to different concentrations of MTBE were examined. MTBE was toxic to both earthworm species and the severity of response increased with increasing MTBE concentrations. Perionyx excavatus was more sensitive to MTBE than Eisenia andrei in filter papers and two different types of soils. MTBE toxicity was more severe in OECD artificial soils than in field soils, possibly due to the burrowing behavior of earthworms into artificial soils. The present study demonstrated that ecotoxicity of volatile organic compounds such as MTBE can be assessed using an earthworm bioassay in closed soil microcosm with short-term exposure duration. - Earthworm bioassay can be a good protocol to assess soil ecotoxicity of volatile organic compounds such as MTBE

  16. Identification of a Ruminococcaceae Species as the Methyl tert-Butyl Ether (MTBE) Degrading Bacterium in a Methanogenic Consortium.

    Science.gov (United States)

    Liu, Tong; Ahn, Hyeri; Sun, Weimin; McGuinness, Lora R; Kerkhof, Lee J; Häggblom, Max M

    2016-02-01

    The widespread use of methyl tert-butyl ether (MTBE) has caused major contamination of groundwater sources and is a concern due to its taste and odor problems, as well as its toxicity. MTBE can be degraded anaerobically which makes bioremediation of contaminated aquifers a potential solution. Nevertheless, the organisms and mechanisms that are responsible for anaerobic MTBE degradation are still unknown. The aim of our research was to identify the organisms actively degrading MTBE. For this purpose we characterized an anaerobic methanogenic culture enriched with MTBE as the sole carbon source from the New Jersey Arthur Kill intertidal strait sediment. The cultures were analyzed using stable isotope probing (SIP) combined with terminal restriction fragment length polymorphism (T-RFLP), high-throughput sequencing and clone library analysis of bacterial 16S rRNA genes. The sequence data indicated that phylotypes belonging to the Ruminococcaceae in the Firmicutes were predominant in the methanogenic cultures. SIP experiments also showed sequential incorporation of the (13)C labeled MTBE by the bacterial community with a bacterium most closely related to Saccharofermentans acetigenes identified as the bacterium active in O-demethylation of MTBE. Identification of the microorganisms responsible for the activity will help us better understand anaerobic MTBE degradation processes in the field and determine biomarkers for monitoring natural attenuation. PMID:26727046

  17. Aldh2 knockout mice were more sensitive to DNA damage in leukocytes due to ethyl tertiary butyl ether exposure.

    Science.gov (United States)

    Weng, Zuquan; Suda, Megumi; Ohtani, Katsumi; Mei, Nan; Kawamoto, Toshihiro; Nakajima, Tamie; Wang, Rui-Sheng

    2011-01-01

    To clarify the genotoxicity of ethyl tertiary butyl ether (ETBE), a gasoline additive, male and female C57BL/6 mice of Aldh2+/+ and Aldh2-/- genotypes, aged 8 wk, were exposed to 0, 500, 1,750, or 5,000 ppm ETBE for 6 h/day, 5 d per week for 13 wk. DNA damage in leukocytes was measured by the alkaline comet assay and expressed quantitatively as Tail Intensity (TI). For male mice, TI was significantly higher in all three groups exposed to ETBE than in those without exposure within Aldh2-/- mice, whereas within Aldh2+/+ mice, TI increased only in those exposed to 5,000 ppm of ETBE as compared with mice without exposure. For female mice, a significant increase in TI values was observed in the group exposed to 5,000 ppm of ETBE as compared with those without exposure within Aldh2-/- mice; TI in Aldh2-/- mice exposed to 1,750 and 5,000 ppm was significantly higher than in Aldh2+/+ mice without exposure. TI did not significantly increase in any of the groups exposed to ETBE within female Aldh2+/+ mice. Based on the results we suggest that Aldh2-/- mice are more sensitive to DNA damage caused by ETBE than Aldh2+/+ mice and that males seem more susceptible to this effect than females. PMID:21372431

  18. Assessing soil ecotoxicity of methyl tert-butyl ether using earthworm bioassay; closed soil microcosm test for volatile organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    An, Youn-Joo [Department of Environmental Science, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701 (Korea, Republic of)]. E-mail: anyjoo@konkuk.ac.kr

    2005-03-01

    An earthworm bioassay was conducted to assess ecotoxicity in methyl tert-butyl ether (MTBE)-amended soils. Ecotoxicity of MTBE to earthworms was evaluated by a paper contact method, natural field soil test, and an OECD artificial soil test. All tests were conducted in closed systems to prevent volatilization of MTBE out of test units. Test earthworm species were Perionyx excavatus and Eisenia andrei. Mortality and abnormal morphology of earthworms exposed to different concentrations of MTBE were examined. MTBE was toxic to both earthworm species and the severity of response increased with increasing MTBE concentrations. Perionyx excavatus was more sensitive to MTBE than Eisenia andrei in filter papers and two different types of soils. MTBE toxicity was more severe in OECD artificial soils than in field soils, possibly due to the burrowing behavior of earthworms into artificial soils. The present study demonstrated that ecotoxicity of volatile organic compounds such as MTBE can be assessed using an earthworm bioassay in closed soil microcosm with short-term exposure duration. - Earthworm bioassay can be a good protocol to assess soil ecotoxicity of volatile organic compounds such as MTBE.

  19. New amphiphilic PEG-b-P(ester-ether) micelles as potential drug nanocarriers

    Energy Technology Data Exchange (ETDEWEB)

    Jeetah, Roubeena; Bhaw-Luximon, Archana; Jhurry, Dhanjay, E-mail: dhanjay.jhurry@gmail.com [University of Mauritius, ANDI Centre of Excellence for Biomedical and Biomaterials Research, MSIRI Building (Mauritius)

    2012-10-15

    A range of diblock and triblock copolymers of dioxanone and methyl dioxanone (MeDX) were synthesized by ring-opening polymerization of dioxanone and MeDX initiated by hydroxyl-terminated PEG (MPEG) or di-amino-terminated PEG (Jeffamine{sup Registered-Sign }) as macroinitiator in the presence of Sn(Oct){sub 2}. The copolymers exhibit amphiphilic behavior in water forming core-shell micelles in the size range 120-300 nm as measured by DLS. DSC measurements exhibit only one melting transition for all copolymers and confirm that increasing MeDX content of the copolymers lead to decreasing crystalline character and hydrophobic-hydrophilic chain entanglement. Anti-inflammatory drug ketoprofen was successfully loaded into the hydrophobic core of the micelles. Various key parameters such as micelle size, drug entrapment efficiency and drug release, which are dependent on crystalline structure and biodegradability characteristics of the hydrophobic core, could effectively be controlled by varying the dioxanone/MeDX ratio of the (ester-ether) copolymer.

  20. Microbial dynamics in anaerobic enrichment cultures degrading di-n-butyl phthalic acid ester

    DEFF Research Database (Denmark)

    Trably, Eric; Batstone, Damien J.; Christensen, Nina;

    2008-01-01

    enrichment cultures degrading phthalic acid esters under methanogenic conditions. A selection pressure was applied by adding DBP at 10 and 200 mg L(-1) in semi-continuous anaerobic reactors. The microbial dynamics were monitored using single strand conformation polymorphism (SSCP). While only limited abiotic...... microorganism described previously as an anaerobic benzaldehyde degrader. Within the archaeal community, there was a shift between two different species of the genus Methanosaeta sp., indicating a highly specific impact of DBP or degradation products on archaeal species. RNA-directed probes were designed from...

  1. The Effect of Water Contaminated with Methyl Tertiary Butyl Ether (MTBE) on the Rat's Weight and Tissue

    International Nuclear Information System (INIS)

    Lead is known to cause deleterious effects on health and environment. Therefore, it was removed from car-fuel, in the United States since 1979. In January 2001, Saudi Arabia and other Arabian Gulf States, replaced lead with a synthetic organic substance called methyl tertiary-butyl ether (MTBE). MTBE is added to gasoline at 12-15%. It dissolves readily in water and evaporates quickly. This study was focused on the possible health hazards of MTBE in drinking water as manifested by changes in weight and vital tissues (heart, liver, kidney, lung, and testis) of rat. This study also aimed to establish a quantitative relationship between MTBE concentration and changes that occur to these tissues. One hundred and twenty male Wistar rats were exposed to five different MTBE concentrations (0.0, 1,000, 1,500, 2,000, 2,500 ppm) for 60 days. The results showed that most of MTBE-treated animals have revealed significant weight loss and the maximum weight loss (nearly 10 %) was achieved at the highest concentration (2,500 ppm) after 60 days of treatment. Also, both liver and heart weights were significantly reduced by almost 9%, and kidneys by 8% of MTBE concentration of 2,000 ppm. At a higher concentration (2,500 ppm), liver weight was reduced by 12%. The weight of other tissues (lungs and testes) remained unchanged. The outcome of the results may lead to hepatic disorder. This disorder could reduce plasma glucose, or increase some hepatic markers like ALT, AST, and GGT activity, or elevate the levels of sodium and chloride in plasma and may have other side effects. (author)

  2. Whole-genorne analysis of the methyl tert-butyl ether-degrading beta-proteobacterium Methylibium petroleiphilum PM1

    Energy Technology Data Exchange (ETDEWEB)

    Kane, Staci R. [Lawrence Livermore National Laboratory (LLNL); Chakicherla, Anu Y. [Lawrence Livermore National Laboratory (LLNL); Chain, Patrick S. G. [Lawrence Livermore National Laboratory (LLNL); Schmidt, Radomir [University of California, Davis; Shin, M [U.S. Department of Energy, Joint Genome Institute; Legler, Tina C. [Lawrence Livermore National Laboratory (LLNL); Scow, Kate M. [University of California, Davis; Larimer, Frank W [ORNL; Lucas, Susan [Joint Genome Institute, Walnut Creek, California; Richardson, P M [U.S. Department of Energy, Joint Genome Institute; Hristova, Krassimira R. [University of California, Davis

    2007-03-01

    Methylibium petroleiphilum PM1 is a methylotroph distinguished by its ability to completely metabolize the fuel oxygenate methyl tert-butyl ether (MTBE). Strain PM1 also degrades aromatic (benzene, toluene, and xylene) and straight-chain (C, to C,,) hydrocarbons present in petroleum products. Whole-genome analysis of PM1 revealed an similar to 4-Mb circular chromosome and an similar to 600-kb megaplasmid, containing 3,831 and 646 genes, respectively. Aromatic hydrocarbon and alkane degradation, metal resistance, and methylotrophy are encoded on the chromosome. The megaplasmid contains an unusual t-RNA island, numerous insertion sequences, and large repeated elements, including a 40-kb region also present on the chromosome and a 29-kb tandem repeat encoding phosphonate transport and cobalamin biosynthesis. The megaplasmid also codes for alkane degradation and was shown to play an essential role in MTBE degradation through plasmid-curing experiments. Discrepancies between the insertion sequence element distribution patterns, the distributions of best BLASTP hits among major phylogenetic groups, and the G+C contents of the chromosome (69.2%) and plasmid (66%), together with comparative genome hybridization experiments, suggest that the plasmid was recently acquired and apparently carries the genetic information responsible for PM1's ability to degrade MTBE. Comparative genomic hybridization analysis with two PM1-like MTBE-degrading environmental isolates (similar to 99% identical 16S rRNA gene sequences) showed that the plasmid was highly conserved (ca. 99% identical), whereas the chromosomes were too diverse to conduct resequencing analysis. PM1's genome sequence provides a foundation for investigating MTBE biodegradation and exploring the genetic regulation of multiple biodegradation pathways in M. petroleiphilum and other MTBE-degrading beta-proteobacteria.

  3. Exposure to methyl tert-butyl ether, benzene, and total hydrocarbons at the Singapore-Malaysia causeway immigration checkpoint

    Energy Technology Data Exchange (ETDEWEB)

    Tan, C.; Ong, H.Y.; Kok, P.W. [and others

    1996-12-31

    The primary aim of this study was to determine the extent and levels of exposure to volatile organic compounds (VOCs) from automobile emissions in a group of immigration officers at a busy cross-border checkpoint. A majority (80%) of the workers monitored were exposed to benzene at levels between 0.01 and 0.5 ppm, with only 1.2% exceeding the current Occupational Safety and Health Administration occupational exposure limit of 1 ppm. The geometric mean (GM) concentrations of 8-hr time-weighted average exposure were 0.03 ppm, 0.9 ppm, and 2.46 ppm for methyl-tert-butyl ether (MTBE), benzene, and total hydrocarbons (THC), respectively. The highest time-weighted average concentrations measured were 1.05 ppm for MTBE, 2.01 ppm for benzene, and 34 ppm for THC. It was found that motorbikes emitted a more significant amount of pollutants compared with motor cars. On average, officers at the motorcycle booths were exposed to four to five times higher levels of VOCs (GMs of 0.07 ppm, 0.23 ppm, and 4.7 ppm for MTBE, benzene, and THC) than their counterparts at the motor car booths (GMs of 0.01 ppm, 0.05 ppm, and 1.5 ppm). The airborne concentrations of all three pollutants correlated with the flow of vehicle traffic. Close correlations were also noted for the concentrations in ambient air for the three pollutants measured. Benzene and MTBE had a correlation coefficient of 0.97. The overall findings showed that the concentrations of various VOCs were closely related to the traffic density, suggesting that they were from a common source, such as exhaust emissions from the vehicles. The results also indicated that although benzene, MTBE, and THC are known to be volatile, a significant amount could still be detected in the ambient environment, thus contributing to our exposure to these compounds. 4 refs., 6 figs.

  4. The interactions of methyl tert-butyl ether on high silica zeolites: a combined experimental and computational study.

    Science.gov (United States)

    Sacchetto, V; Gatti, G; Paul, G; Braschi, I; Berlier, G; Cossi, M; Marchese, L; Bagatin, R; Bisio, C

    2013-08-28

    In this work, the interactions of methyl tert-butyl ether (MTBE) on different dealuminated high silica zeolites were studied by means of both experimental and computational approaches. Zeolites with different textural and surface features were selected as adsorbents and the effect of their physico-chemical properties (i.e. pore size architecture and type and amount of surface OH sites) on sorption capacity were studied. High silica mordenite (MOR) and Y zeolites (both with a SiO2/Al2O3 ratio of 200) and ZSM-5 solid (SiO2/Al2O3 ratio of 500) were selected as model sorbents. By combining FTIR and SS-NMR (both (1)H and (13)C CPMAS NMR) spectroscopy it was possible to follow accurately the MTBE adsorption process on highly defective MOR characterized by a high concentration of surface SiOH groups. The adsorption process is found to occur in different steps and to involve isolated silanol sites, weakly interacting silanols, and the siloxane network of the zeolite, respectively. H-bonding and van der Waals interactions occurring between the mordenite surface and MTBE molecules were modeled by DFT calculations using a large cluster of the MOR structure where two adjacent side-pockets were fused in a large micropore to simulate a dealumination process leading to silanol groups. This is the locus where MTBE molecules are more strongly bound and stabilized. FTIR spectroscopy and gravimetric measurements allowed determination of the interaction strength and sorption capacities of all three zeolites. In the case of both Y and MOR zeolites, medium-weak H-bonding with isolated silanols (both on internal and external zeolite surfaces) and van der Waals interactions are responsible for MTBE adsorption, whereas ZSM-5, in which a negligible amount of surface silanol species is present, displays a much lower amount of adsorbed MTBE retained mainly through van der Waals interactions with zeolite siloxane network. PMID:23860729

  5. Densities and isobaric vapor-liquid equilibria for the mixtures formed by four butyl esters and 1-butanol

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, E.; Ortega, J. [Univ. of Las Palmas de Gran Canaria (Spain)

    1996-01-01

    Densities of 298.15 K and the vapor-liquid equilibria for 1-butanol + butyl methanoate, + butyl ethanoate, + butyl propanoate, and + butyl butanoate have been measured at 101.32 kPa in small capacity ebulliometer. All results were found to be thermodynamically consistent with a point-to-point test. The mixtures containing butyl methanoate and butyl ethanoate show azeotropes at T = 379.14 K, x = 0.871 and T = 389.64 K, x = 0.222, respectively. Different group-contribution methods were applied to these mixtures.

  6. Synthesis and characterization of poly(D,L-lactide)-poly(ethylene glycol) multiblock poly(ether-ester-urethane)s

    Science.gov (United States)

    Haw, Tan Ching; Ahmad, Azizan; Anuar, Farah Hannan

    2015-09-01

    In this study, poly(D,L-lactide)-poly(ethylene glycol) multiblock poly(ether-ester-urethane)s was synthesized in the framework of environmental friendly products to meet the need for highly flexible polymers. Triblock copolymer with poly(ethylene glycol) as center block and poly(D,L-lactide) as side block were first synthesized by ring-opening polymerization of D,L-lactide, followed by chain extension reaction of triblocks using hexamethylene diisocyanate (HMDI). NMR and infra-red spectroscopies were used to determine the molecular composition whereas XRD analysis revealed crystallinity behavior of synthesized multiblock copolymers.

  7. Volumetric Behaviour of the Ternary System (Methyl Tert-butyl ether + Methylbenzene + Butan-1-ol) and Its Binary sub-System (Methyl Tert-Butyl Ether + Butan-1-ol) within the Temperature Range (298.15–328.15) K

    Czech Academy of Sciences Publication Activity Database

    Morávková, Lenka; Troncoso, J.; Škvorová, M.; Havlica, Jaromír; Petrus, P.; Sedláková, Zuzana

    2015-01-01

    Roč. 90, NOV 2015 (2015), s. 59-70. ISSN 0021-9614 R&D Projects: GA ČR(CZ) GAP105/12/0664; GA MŠk(CZ) LD14094 Grant ostatní: GNIL(IT) 408 REGALIs (CN2012/120) Institutional support: RVO:67985858 Keywords : methylbenzene * density * methyl-tert-butyl ether Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.679, year: 2014

  8. Determination of methyl tert-butyl ether (MTBE) in Chinese fuels by gas chromatography/mass spectrometry and gas chromatography/flame ionization detector

    Institute of Scientific and Technical Information of China (English)

    LIU Jie-min; CHENG Wei; WEN Mei-juan; JIANG Gui-bin

    2004-01-01

    A method was developed to determine the concentration of methyl tert-butyl ether(MTBE) in gasoline,diesel and heating oil by gas chromatography(GC) with mass spectrometry(GC-MS) or flame ionization detection (FID). The diluted gasoline was directly injected into the GC, and the complete separation of MTBE from co-eluting hydrocarbons was not required. GC/MS or GC/FID method can be used to analyze MTBE in different concentration range and have good consistency.

  9. Excess enthalpy, density, and speed of sound determination for the ternary mixture (methyl tert-butyl ether + 1-butanol + n-hexane)

    Energy Technology Data Exchange (ETDEWEB)

    Mascato, Eva [Departamento de Fisica Aplicada, Facultade de Ciencias, Universidade de Vigo, E-36310 Vigo (Spain); Mariano, Alejandra [Laboratorio de Fisicoquimica, Departamento de Quimica, Facultad de Ingenieria, Universidad Nacional del Comahue, 8300 Neuquen (Argentina); Pineiro, Manuel M. [Departamento de Fisica Aplicada, Facultade de Ciencias, Universidade de Vigo, E-36310 Vigo (Spain)], E-mail: mmpineiro@uvigo.es; Legido, Jose Luis [Departamento de Fisica Aplicada, Facultade de Ciencias, Universidade de Vigo, E-36310 Vigo (Spain); Paz Andrade, M.I. [Departamento de Fisica Aplicada, Facultade de Fisica, Universidade de Santiago de Compostela, E-15706 Santiago de Compostela (Spain)

    2007-09-15

    Density, ({rho}), and speed of sound, (u), from T = 288.15 to T = 308.15 K, and excess molar enthalpies, (h{sup E}) at T = 298.15 K, have been measured over the entire composition range for (methyl tert-butyl ether + 1-butanol + n-hexane). In addition, excess molar volumes, V{sup E}, and excess isentropic compressibility, {kappa}{sub s}{sup E}, were calculated from experimental data. Finally, experimental excess enthalpies results are compared with the estimations obtained by applying the group-contribution models of UNIFAC (in the versions of Dang and Tassios, Larsen et al., Gmehling et al.), and DISQUAC.

  10. Liquid Phase Dehydration of 1-Butanol to Di-n-butyl ether Experimental Performance, Modeling and Simulation of Ion Exchange Resins as Catalysts

    OpenAIRE

    Pérez-Maciá, María Ángeles

    2015-01-01

    [eng] Di-n-butyl ether (DNBE) is considered a very attractive oxygenate compound to reformulate diesel fuel. The research work performed along this thesis has clearly proven that sulfonic P(S-DVB) ion exchange resins are suitable catalysts for the synthesis of DNBE from the liquid phase dehydration of 1-butanol at the temperature range of 140-190 °C. A catalyst screening of acidic P(S-DVB) ion exchange resins showed that resins activity is enhanced with high acid capacities and with polymer m...

  11. Chemical kinetic study of a novel lignocellulosic biofuel: Di-n-butyl ether oxidation in a laminar flow reactor and flames

    KAUST Repository

    Cai, Liming

    2014-03-01

    The combustion characteristics of promising alternative fuels have been studied extensively in the recent years. Nevertheless, the pyrolysis and oxidation kinetics for many oxygenated fuels are not well characterized compared to those of hydrocarbons. In the present investigation, the first chemical kinetic study of a long-chain linear symmetric ether, di-n-butyl ether (DBE), is presented and a detailed reaction model is developed. DBE has been identified recently as a candidate biofuel produced from lignocellulosic biomass. The model includes both high temperature and low temperature reaction pathways with reaction rates generated using appropriate rate rules. In addition, experimental studies on fundamental combustion characteristics, such as ignition delay times and laminar flame speeds have been performed. A laminar flow reactor was used to determine the ignition delay times of lean and stoichiometric DBE/air mixtures. The laminar flame speeds of DBE/air mixtures were measured in the stagnation flame configuration for a wide rage of equivalence ratios at atmospheric pressure and an unburned reactant temperature of 373. K. All experimental data were modeled using the present kinetic model. The agreement between measured and computed results is satisfactory, and the model was used to elucidate the oxidation pathways of DBE. The dissociation of keto-hydroperoxides, leading to radical chain branching was found to dominate the ignition of DBE in the low temperature regime. The results of the present numerical and experimental study of the oxidation of di-n-butyl ether provide a good basis for further investigation of long chain linear and branched ethers. © 2013 The Combustion Institute.

  12. Manipulation of the HIF–Vegf pathway rescues methyl tert-butyl ether (MTBE)-induced vascular lesions

    Energy Technology Data Exchange (ETDEWEB)

    Bonventre, Josephine A., E-mail: josephine.bonventre@oregonstate.edu [Rutgers, The State University of New Jersey, Joint Graduate Program in Toxicology, 170 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Rutgers, The State University of New Jersey, Department of Biochemistry and Microbiology, 76 Lipman Dr., New Brunswick, NJ 08901 (United States); Oregon State University, Department of Environmental and Molecular Toxicology, 1011 Agricultural and Life Sciences Bldg, Corvallis, OR 97331 (United States); Kung, Tiffany S., E-mail: tiffany.kung@rutgers.edu [Rutgers, The State University of New Jersey, Joint Graduate Program in Toxicology, 170 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Rutgers, The State University of New Jersey, Department of Biochemistry and Microbiology, 76 Lipman Dr., New Brunswick, NJ 08901 (United States); White, Lori A., E-mail: lawhite@aesop.rutgers.edu [Rutgers, The State University of New Jersey, Joint Graduate Program in Toxicology, 170 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Rutgers, The State University of New Jersey, Department of Biochemistry and Microbiology, 76 Lipman Dr., New Brunswick, NJ 08901 (United States); Cooper, Keith R., E-mail: cooper@aesop.rutgers.edu [Rutgers, The State University of New Jersey, Joint Graduate Program in Toxicology, 170 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Rutgers, The State University of New Jersey, Department of Biochemistry and Microbiology, 76 Lipman Dr., New Brunswick, NJ 08901 (United States)

    2013-12-15

    Methyl tert-butyl ether (MTBE) has been shown to be specifically anti-angiogenic in piscine and mammalian model systems at concentrations that appear non-toxic in other organ systems. The mechanism by which MTBE targets developing vascular structures is unknown. A global transcriptome analysis of zebrafish embryos developmentally exposed to 0.00625–5 mM MTBE suggested that hypoxia inducible factor (HIF)-regulated pathways were affected. HIF-driven angiogenesis via vascular endothelial growth factor (vegf) is essential to the developing vasculature of an embryo. Three rescue studies were designed to rescue MTBE-induced vascular lesions: pooled blood in the common cardinal vein (CCV), cranial hemorrhages (CH), and abnormal intersegmental vessels (ISV), and test the hypothesis that MTBE toxicity was HIF–Vegf dependent. First, zebrafish vegf-a over-expression via plasmid injection, resulted in significantly fewer CH and ISV lesions, 46 and 35% respectively, in embryos exposed to 10 mM MTBE. Then HIF degradation was inhibited in two ways. Chemical rescue by N-oxaloylglycine significantly reduced CCV and CH lesions by 30 and 32% in 10 mM exposed embryos, and ISV lesions were reduced 24% in 5 mM exposed zebrafish. Finally, a morpholino designed to knock-down ubiquitin associated von Hippel–Lindau protein, significantly reduced CCV lesions by 35% in 10 mM exposed embryos. In addition, expression of some angiogenesis related genes altered by MTBE exposure were rescued. These studies demonstrated that MTBE vascular toxicity is mediated by a down regulation of HIF–Vegf driven angiogenesis. The selective toxicity of MTBE toward developing vasculature makes it a potentially useful chemical in the designing of new drugs or in elucidating roles for specific angiogenic proteins in future studies of vascular development. - Highlights: • Global gene expression of MTBE exposed zebrafish suggested altered HIF1 signaling. • Over expression of zebrafish vegf-a rescues MTBE

  13. Ether- and ester-bound iso-diabolic acid and other lipids in members of acidobacteria subdivision 4.

    Science.gov (United States)

    Sinninghe Damsté, Jaap S; Rijpstra, W Irene C; Hopmans, Ellen C; Foesel, Bärbel U; Wüst, Pia K; Overmann, Jörg; Tank, Marcus; Bryant, Donald A; Dunfield, Peter F; Houghton, Karen; Stott, Matthew B

    2014-09-01

    Recently, iso-diabolic acid (13,16-dimethyl octacosanedioic acid) has been identified as a major membrane-spanning lipid of subdivisions 1 and 3 of the Acidobacteria, a highly diverse phylum within the Bacteria. This finding pointed to the Acidobacteria as a potential source for the bacterial glycerol dialkyl glycerol tetraethers that occur ubiquitously in peat, soil, lakes, and hot springs. Here, we examined the lipid composition of seven phylogenetically divergent strains of subdivision 4 of the Acidobacteria, a bacterial group that is commonly encountered in soil. Acid hydrolysis of total cell material released iso-diabolic acid derivatives in substantial quantities (11 to 48% of all fatty acids). In contrast to subdivisions 1 and 3 of the Acidobacteria, 6 out of the 7 species of subdivision 4 (excepting "Candidatus Chloracidobacterium thermophilum") contained iso-diabolic acid ether bound to a glycerol in larger fractional abundance than iso-diabolic acid itself. This is in agreement with the analysis of intact polar lipids (IPLs) by high-performance liquid chromatography-mass spectrometry (HPLC-MS), which showed the dominance of mixed ether-ester glycerides. iso-Diabolic acid-containing IPLs were not identified, because these IPLs are not released with a Bligh-Dyer extraction, as observed before when studying lipid compositions of subdivisions 1 and 3 of the Acidobacteria. The presence of ether bonds in the membrane lipids does not seem to be an adaptation to temperature, because the five mesophilic isolates contained a larger amount of ether lipids than the thermophile "Ca. Chloracidobacterium thermophilum." Furthermore, experiments with Pyrinomonas methylaliphatogenes did not reveal a major influence of growth temperature over the 50 to 69°C range. PMID:24928878

  14. Mechanistic Study of the sPLAMediated Hydrolysis of a Thio-ester Pro Anticancer Ether Lipid

    DEFF Research Database (Denmark)

    Linderoth, Lars; Fristrup, Peter; Hansen, Martin;

    2009-01-01

    Secretory phospholipase A2 (sPLA2) is an interesting enzyme for triggered liposomal drug delivery to tumor tissue due the overexpression of sPLA2 in cancerous tissue. A drug delivery system based on the triggered release of therapeutics from sPLA2-sensitive liposomes constituted of pro anticancer...... ether lipids, which become cytotoxic upon sPLA2-catalyzed hydrolysis has previously been established. To optimize the hydrolysis rate of the lipids and thereby optimizing the release profile of the drugs from the liposomes, we have synthesized a thio-ester pro anticancer ether lipid. Liposomes...... constituted of this lipid showed an altered rate of hydrolysis by sPLA2. We have tested the cytotoxicity of the thio-ester pro anticancer ether lipids toward cancer cells, and the results showed that the cytotoxicity is indeed maintained upon sPLA2 exposure. To further understand the origin for the observed...

  15. Cytotoxic and DNA-damaging effects of methyl tert-butyl ether and its metabolites on HL-60 cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Tang, G.H. [Xian Medical Univ. (China); Shen, Y.; Shen, H.M. [National Univ. of Singapore (Singapore)] [and others

    1996-12-31

    Methyl tert-butyl ether (MTBE) is a widely used oxygenate in unleaded gasoline; however, few studies have been conducted on the toxicity of this compound. This study evaluates the cytotoxic and DNA-damaging effects of MTBE and its metabolites in a human haemopoietic cell line, HL-60. The metabolites of MTBE studied include tertiary butyl alcohol (TBA), {alpha}-hydroxyisobutyric acid (HIBA), and formaldehyde. Comet assay is used to assess DNA damage, and the cytotoxicity is investigated by lactate dehydrogenease (LDH) release. The results show no significant cytotoxic effects of MTBE, TBA, and HIBA over a concentration ranging from 1 to 30 mM. Formaldehyde, in contrast, causes a substantial LDH release at a concentration of 5 {mu}M. Hydrogen peroxide, a known oxidative agent, at concentrations ranging from 10 to 100 {mu}M, produces a significant dose-related increase in DNA damage, whereas a much higher concentration of MTBE (1 to 30 mM) is required to produce a similar observation. The genotoxic effects of TBA and HIBA appear to be identical to that of MTBE. Conversely, DNA damage is observed for formaldehyde at a relatively low concentration range (5 to 100 {mu}M). These findings suggest that MTBE and its metabolites, except formaldehyde, have relatively low cytotoxic and genotoxic effects. 16 refs., 4 figs.

  16. Enhancement in Mode II Interlaminar Fracture Toughness at Cryogenic Temperature of Glass Fiber/Epoxy Composites through Matrix Modification by Carbon Nanotubes and n-Butyl Glycidyl Ether

    Directory of Open Access Journals (Sweden)

    Yu Liu

    2015-01-01

    Full Text Available A typical diglycidyl ether of bisphenol-F (DGEBF/diethyl toluene diamine (DETD epoxy system modified by multiwalled carbon nanotubes (MWCNTs and a reactive aliphatic diluent named n-butyl glycidyl ether (BGE was used as the matrix for glass fiber composites. The glass fiber (GF reinforced composites based on the unmodified and modified epoxy matrices were prepared by the hand lay-up hot-press process. Mode II interlaminar fracture toughness at both room temperature (RT and cryogenic temperature (77 K of the GF reinforced epoxy composites was investigated to examine the effect of the matrix modification. The result showed that the introduction of MWCNTs and BGE at their previously reported optimal contents led to the remarkable enhancement in mode II interlaminar fracture toughness of the composites. Namely, the 22.9% enhancement at RT and the 31.4% enhancement at 77 K were observed for mode II interlaminar fracture toughness of the fiber composite based on the optimally modified epoxy matrix by MWCNTs and BGE compared to the unmodified case.

  17. Volumetric behavior of the ternary system (methyl tert-butyl ether + methylbenzene + butan-1-ol) and its binary sub-system (methyl tert-butyl ether + butan-1-ol) within the temperature range (298.15 to 328.15) K

    International Nuclear Information System (INIS)

    Highlights: • Excess molar volume determined from experimental density values. • Excess adiabatic compressibility. • Excess isobaric thermal expansivity. • Peng–Robinson equation of state. • ERAS model. - Abstract: Values of the density and speed of sound were measured for the ternary system (methyl tert-butyl ether + methylbenzene + butan-1-ol) within the temperature range (298.15 to 328.15) K at atmospheric pressure by a vibrating-tube densimeter DSA 5000. Two binary sub-systems were studied and published previously while the binary sub-system (methyl tert-butyl ether + butan-1-ol) is a new study in this work. Excess molar volume, adiabatic compressibility, and isobaric thermal expansivity were calculated from the experimental values of density and speed of sound. The excess quantities were correlated using the Redlich–Kister equation. The experimental excess molar volumes were analyzed by means of both the Extended Real Associated Solution (ERAS) model and the Peng–Robinson equation of state. The novelty of this work is the qualitative prediction of ternary excess molar volumes for the system containing auto-associative compound and two compounds that can hetero-associate. The combination of the ERAS model and Peng–Robinson equation of state could help to qualitatively estimate the real behavior of the studied systems because the experimental results lie between these two predictions

  18. Electron paramagnetic resonance study of free radicals in γ-irradiated L-glutamine and L-glutamine-t-butyl ester hydrochloride

    Science.gov (United States)

    Yeşim Dicle, Işık; Osmanğolu, Şemsettin; İpek, Nazenin

    2015-01-01

    Electron paramagnetic resonance (EPR) spectra of γ-irradiated single crystals of l-glutamine (LG) and l-glutamine-t-butyl ester hydrochloride (LGBESHCI) powders were studied and analyzed for different orientations of the crystals in the magnetic field, after γ-irradiation. The spectra were observed to be independent of temperature down to 130 K. The hyperfine interaction tensors for one α proton and two β protons of radical have been determined at 295 K. An analysis of the EPR of γ-irradiated single crystals of LG and LGBESHCI powders shows that the paramagnetic species produced by the radiation damage is CH2ĊH. The g values of the radical and the hyperfine structure constants of the free electron with nearby protons and 14N nucleus were determined. The results were found to be in good agreement with the existing literature data.

  19. A poly(ether-ester) copolymer for the preparation of nanocarriers with improved degradation and drug delivery kinetics.

    Science.gov (United States)

    Gagliardi, M; Bertero, A; Bardi, G; Bifone, A

    2016-02-01

    This paper reports the synthesis and the physicochemical, functional and biological characterisations of nanocarriers made of a novel di-block biodegradable poly(ether-ester) copolymer. This material presents tunable, fast biodegradation rates, but its products are less acidic than those of other biosorbable polymers like PLGA, thus presenting a better biocompatibility profile and the possibility to carry pH-sensitive payloads. A method for the production of monodisperse and spherical nanoparticles is proposed; drug delivery kinetics and blood protein adsorption were measured to evaluate the functional properties of these nanoparticles as drug carriers. The copolymer was labelled with a fluorescent dye for internalisation tests, and rhodamine B was used as a model cargo to study transport and release inside cultured cells. Biological tests demonstrated good cytocompatibility, significant cell internalisation and the possibility to vehiculate non-cell penetrating moieties into endothelial cells. Taken together, these results support the potential use of this nanoparticulate system for systemic administration of drugs. PMID:26652400

  20. Contamination of phthalate esters, organochlorine pesticides and polybrominated diphenyl ethers in agricultural soils from the Yangtze River Delta of China.

    Science.gov (United States)

    Sun, Jianteng; Pan, Lili; Zhan, Yu; Lu, Hainan; Tsang, Daniel C W; Liu, Wenxin; Wang, Xilong; Li, Xiangdong; Zhu, Lizhong

    2016-02-15

    To reveal the pollution status associated with rapid urbanization and economic growth, extensive areas of agricultural soils (approximately 45,800 km(2)) in the Yangtze River Delta of China were investigated with respect to selected endocrine disruptor compounds (EDCs), including phthalate esters (PAEs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs). The residues of sum of 15 PAEs, sum of 15 OCPs and sum of 13 PBDEs were in the range of 167-9370 ng/g, 1.0-3520 ng/g, and film was considered to be an important source of PAEs. Discharge from furniture industry was potential major source of PBDEs in this region. The selected pollutants showed quite different spatial distributions within the studied region. It is worth noting that much higher concentrations of the EDCs were found on the borders between Shanghai and the two neighboring provinces, where agriculture and industry developed rapidly in recent years. Contaminants from both agricultural and industrial activities made this area a pollution hotspot, which should arouse more stringent regulation to safeguard the environment and food security. PMID:26674696

  1. Preparation of N-tBoc L-glutathione dimethyl and di-tert-butyl esters: versatile synthetic building blocks

    OpenAIRE

    Falck, J. R.; Sangras, Bhavani; Capdevila, Jorge H.

    2006-01-01

    The title L-glutathione derivatives, containing acid- and base-labile esters, respectively, were obtained in good overall yields. N-tBoc L-glutathione dimethyl ester was prepared via Fischer esterification of L-glutathione disulfide (GSSG) using HCl in dry methanol, protection of the amine with tBoc2O, and tributylphosphine cleavage of the disulfide in wet isopropanol. Alternatively, Fischer esterification and tBoc-protection of L-glutathione (GSH) also furnished N-tBoc glutathione dimethyl e...

  2. Foaming Properties of 1,1,3- Triethoxy Butane and Dipropyl Glycol Butyl Ether%1,1,3-三乙氧基丁烷与二丙基二醇丁醚的起泡性能*

    Institute of Scientific and Technical Information of China (English)

    朱一民

    2011-01-01

    1,1,3-三乙氧基丁烷(代号TEB)与二丙基二醇丁醚是同分异构体,根据浮选药剂的同分异构原理,二丙基二醇丁醚亦应与TEB相似,都是良好的起泡剂,并通过某铜矿浮选实践得到了证明.%1,1,3 -triethoxy butane(TEB) and dipropyl glycol butyl ether are isomers. According to the isomerism principle of flotation agent, their floatation performances are also similar. 1,1,3 - triethoxy butane and dipropyl glycol butyl ether are both good foaming agents. It had been found that this deduction was correct by floatation practice of a copper ore.

  3. Stable isotope determination of ester and ether methyl moieties in plant methoxyl groups.

    Science.gov (United States)

    Greule, Markus; Keppler, Frank

    2011-12-01

    Plant methoxyl groups of lignin and pectin have both distinct stable hydrogen isotope (δ(2)H) and carbon isotope (δ(13)C) values that can be used for studying environmental processes and for investigating the origin and authenticity of biomaterials. Up to now, the reported methods have been applied only to determine isotope values of the bulk plant methoxyl pool. In this work, we have applied several methods to distinguish between stable isotope ratios of methoxyl groups of pectin and the bulk plant methoxyl pool. Our results demonstrate that by applying alkaline hydrolysis to specifically cleave off the ester methyl moiety (pectin-like), we can distinguish δ(2)H and δ(13)C values of the pectin methoxyl pool from the bulk methoxyl pool. No measureable isotope discrimination was observed either during sample preparation or during analytical measurement. Furthermore, using this method, no major isotope difference in either the hydrogen or carbon isotope signature of the methoxyl groups of plant pectin and bulk matter from plant species such as leaves from trees, apples, carrots and potatoes was noted. We show the methanol released during alkaline hydrolysis of plant material and subsequently treated with hydriodic acid to be an excellent procedure to measure specifically and precisely the δ(13)C and δ(2)H isotope values of plant pectin-like methoxyl groups. This method is particularly advantageous when plant matter with a low methoxyl content has to be analysed. PMID:22004278

  4. Determination of Methyl tert-Butyl Ether and tert-Butyl Alcohol in Water by Solid-Phase Microextraction/Head Space Analysis in Comparison to EPA Method 5030/8260B

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Keun-Chan; Stringfellow, William T.

    2003-10-02

    Methyl tert-butyl ether (MTBE) is now one of the most common groundwater contaminants in the United States. Groundwater contaminated with MTBE is also likely to be contaminated with tert-butyl alcohol (TBA), because TBA is a component of commercial grade MTBE, TBA can also be used as a fuel oxygenate, and TBA is a biodegradation product of MTBE. In California, MTBE is subject to reporting at concentrations greater than 3 {micro}g/L. TBA is classified as a ''contaminant of current interest'' and has a drinking water action level of 12 {micro}g/L. In this paper, we describe the development and optimization of a simple, automated solid phase microextraction (SPME) method for the analysis of MTBE and TBA in water and demonstrate the applicability of this method for monitoring MTBE and TBA contamination in groundwater, drinking water, and surface water. In this method, the headspace (HS) of a water sample is extracted with a carboxen/polydimethylsiloxane SPME fiber, the MTBE and TBA are desorbed into a gas chromatograph (GC), and detected using mass spectrometry (MS). The method is optimized for the routine analysis of MTBE and TBA with a level of quantitation of 0.3 {micro}g/L and 4 {micro}g/L, respectively, in water. MTBE quantitation was linear for over two orders of concentration (0.3 {micro}g/L -80 {micro}g/L). TBA was found to be linear within the range of 4 {micro}g/L-7,900 {micro}g/L. The lower level of detection for MTBE is 0.03 {micro}g/L using this method. This SPME method using headspace extraction was found to be advantageous over SPME methods requiring immersion of the fiber into the water samples, because it prolonged the life of the fiber by up to 400 sample analyses. This is the first time headspace extraction SPME has been shown to be applicable to the measurement of both MTBE and TBA at concentrations below regulatory action levels. This method was compared with the certified EPA Method 5030/8260B (purge-and-trap/GC/MS) using split

  5. Interaction of insulin with methyl tert-butyl ether promotes molten globule-like state and production of reactive oxygen species.

    Science.gov (United States)

    Valipour, Masoumeh; Maghami, Parvaneh; Habibi-Rezaei, Mehran; Sadeghpour, Mostafa; Khademian, Mohamad Ali; Mosavi, Khadijeh; Sheibani, Nader; Moosavi-Movahedi, Ali Akbar

    2015-09-01

    Interaction of methyl tert-butyl ether (MTBE) with proteins is a new look at its potential adverse biological effects. When MTBE is released to the environment it enters the blood stream through inhalation, and could affect the properties of various proteins. Here we investigated the interaction of MTBE with insulin and its effect on insulin structural changes. Our results showed that insulin formed a molten globule (MG)-like structure in the presence of 8 μM MTBE under physiological pH. The insulin structural changes were studied using spectroscopy methods, viscosity calculation, dynamic light scattering and differential scanning calorimetry. To delineate the mechanisms involved in MTBE-protein interactions, the formation of reactive oxygen specious (ROS) and formation of protein aggregates were measured. The chemiluminscence experiments revealed an increase in ROS production in the presence of MTBE especially in the MG-like state. These results were further confirmed by the aggregation tests, which indicated more aggregation of insulin at 40 μM MTBE compared with 8 μM. Thus, the formation of initial aggregates and exposure of the hydrophobic patches upon formation of the MG-like state in the presence of MTBE drives protein oxidation and ROS generation. PMID:26193678

  6. Diethylene glycol mono butyl ether concentrations in room air from application of cleaner formulations to hard surfaces.

    Science.gov (United States)

    Gibson, W B; Keller, P R; Foltz, D J; Harvey, G J

    1991-07-01

    Diethylene glycol monobutyl ether (DGBE) is a solvent used in some liquid hard surface cleaners. We evaluated the inhalation component of consumer exposure in the home to DGBE from the use of cleaning products containing up to 9% DGBE. Several experiments were conducted with restricted room air flow, exaggerated amounts of cleaning solutions, and no rinsing in order to develop an exposure scenario that would exceed exposures likely encountered by consumers. DGBE vapors in the air were monitored by collection on charcoal tubes, followed by desorption and quantitation by gas chromatography. Air was collected from the centre of the room and from the breathing zone of the person doing the washing task. Room air concentrations of DGBE showed peak values between one and three hours after task initiation; DGBE concentrations then gradually decreased with time. Peak concentrations did not exceed 1.6 ppmv. The total DGBE in the air at the time of maximum air concentrations accounted for only 1 to 3% of the DGBE on the washed surfaces. The person doing the washing task was exposed to average DGBE concentrations in the breathing zone below 0.8 ppmv in all experiments. The methods described for measuring DGBE concentrations in air are generally applicable to other solvents and easily adaptable to various experimental situations. PMID:1824325

  7. N-(二苯基亚甲基)甘氨酸叔丁基酯的合成%Synthesis of N-(diphenylmethylene)Glycine Tert-Butyl Ester

    Institute of Scientific and Technical Information of China (English)

    聂友松; 钟敏; 李航; 贺贤然

    2015-01-01

    The N-(diphenylmethylene)glycine tert-butyl ester has been accomplished in 4 steps from phthalic anhydride and glycine with good yield. The last step in this approach is a condensation reaction of benzophenone with glycine tert-butyl ester using the Iron (III) chloride hexahydrate as a catalyst , which is a convenient synthetic method.%N-(二苯基亚甲基)甘氨酸叔丁基酯可由邻苯二甲酸酐和甘氨酸分4个步骤制得,且产率可观。此方法的最后一步是二苯甲酮与甘氨酸叔丁酯的缩合反应,以氯化铁六水合物为催化剂,该合成方法方便可行。

  8. Studies of a pyridino-crown ether-based chiral stationary phase on the enantioseparation of biogenic chiral aralkylamines and α-amino acid esters by high-performance liquid chromatography.

    Science.gov (United States)

    Lévai, Sándor; Németh, Tamás; Fődi, Tamás; Kupai, József; Tóth, Tünde; Huszthy, Péter; Balogh, György Tibor

    2015-11-10

    This paper reports the enantioseparation ability of a pyridino-18-crown-6 ether-based chiral stationary phase [(S,S)-CSP-1]. The enantiomeric discrimination of chiral stationary phase (S,S)-CSP-1 was evaluated by HPLC using the mixtures of enantiomers of various protonated primary aralkylamines [1-phenylethylamine hydrogen perchlorate (PEA), 2,3-dihydro-1H-inden-1-amine (1-aminoindan), 2,2'-(1,2-diaminoethane-1,2-diyl) diphenol (HPEN)] and perchlorate salts of α-amino acid esters [alanine benzyl ester (Ala-OBn), phenylalanine benzyl ester (Phe-OBn), phenylalanine methyl ester (Phe-OMe), phenylglycine methyl ester (PhGly-OMe), glutamic acid dibenzyl ester (Glu-diOBn), and valine benzyl ester (Val-OBn)]. The best enantioseparation was achieved in the case of PEA. The high enantioselectivity was rationalized by the strong π-π interaction of the extended π system of the aryl-substituted pyridine unit. PMID:26218505

  9. Application of artificial neural networks for modeling of the treatment of wastewater contaminated with methyl tert-butyl ether (MTBE) by UV/H2O2 process

    International Nuclear Information System (INIS)

    During the last two decades, methyl tert-butyl ether (MTBE) has been widely used as an additive to gasoline (up to 15%) both to increase the octane number and as a fuel oxygenate to improve air quality by reducing the level of carbon monoxide in vehicle exhausts. The present work mainly deals with photooxidative degradation of MTBE in the presence of H2O2 under UV light illumination (30 W). We studied the influence of the basic operational parameters such as initial concentration of H2O2 and irradiation time on the photodegradation of MTBE. The oxidation rate of MTBE was low when the photolysis was carried out in the absence of H2O2 and it was negligible in the absence of UV light. The addition of proper amount of hydrogen peroxide improved the degradation, while the excess hydrogen peroxide could quench the formation of hydroxyl radicals (·OH). The semi-log plot of MTBE concentration versus time was linear, suggesting a first order reaction. Therefore, the treatment efficiency was evaluated by figure-of-merit electrical energy per order (E Eo). Our results showed that MTBE could be treated easily and effectively with the UV/H2O2 process with E Eo value 80 kWh/m3/order. The proposed model based on artificial neural network (ANN) could predict the MTBE concentration during irradiation time in optimized conditions. A comparison between the predicted results of the designed ANN model and experimental data was also conducted

  10. Evaluation of ethyl tert-butyl ether biodegradation in a contaminated aquifer by compound-specific isotope analysis and in situ microcosms

    Energy Technology Data Exchange (ETDEWEB)

    Bombach, Petra, E-mail: petra.bombach@ufz.de [UFZ – Helmholtz Centre for Environmental Research, Department of Isotope Biogeochemistry, Permoserstrasse 15, D-04318 Leipzig (Germany); Isodetect GmbH Leipzig, Deutscher Platz 5b, D-04103 Leipzig (Germany); Nägele, Norbert [Kuvier the Biotech Company S.L., Ctra. N-I, p.k. 234–P.E. INBISA 23" a, E-09001 Burgos (Spain); Rosell, Mònica [UFZ – Helmholtz Centre for Environmental Research, Department of Isotope Biogeochemistry, Permoserstrasse 15, D-04318 Leipzig (Germany); Grup de Mineralogia Aplicada i Medi Ambient, Departament de Cristallografia, Mineralogia i Dipòsits Minerals, Facultat de Geologia, Universitat de Barcelona (UB), C/Martí i Franquès s/n, 08028 Barcelona (Spain); Richnow, Hans H. [UFZ – Helmholtz Centre for Environmental Research, Department of Isotope Biogeochemistry, Permoserstrasse 15, D-04318 Leipzig (Germany); Fischer, Anko [Isodetect GmbH Leipzig, Deutscher Platz 5b, D-04103 Leipzig (Germany)

    2015-04-09

    Highlights: • In situ biodegradation of ETBE was investigated in a fuel contaminated aquifer. • Degradation was studied by CSIA and in situ microcosms in combination with TLFA-SIP. • ETBE was degraded when ETBE was the main groundwater contaminant. • ETBE was also degraded in the presence of BTEX and MTBE. • Hydrochemical analysis indicated aerobic and anaerobic ETBE biodegradation. - Abstract: Ethyl tert-butyl ether (ETBE) is an upcoming groundwater pollutant in Europe whose environmental fate has been less investigated, thus far. In the present study, we investigated the in situ biodegradation of ETBE in a fuel-contaminated aquifer using compound-specific stable isotope analysis (CSIA), and in situ microcosms in combination with total lipid fatty acid (TLFA)-stable isotope probing (SIP). In a first field investigation, CSIA revealed insignificant carbon isotope fractionation, but low hydrogen isotope fractionation of up to +14‰ along the prevailing anoxic ETBE plume suggesting biodegradation of ETBE. Ten months later, oxygen injection was conducted to enhance the biodegradation of petroleum hydrocarbons (PH) at the field site. Within the framework of this remediation measure, in situ microcosms loaded with [{sup 13}C{sub 6}]-ETBE (BACTRAP{sup ®}s) were exposed for 119 days in selected groundwater wells to assess the biodegradation of ETBE by TLFA-SIP under the following conditions: (i) ETBE as main contaminant; (ii) ETBE as main contaminant subjected to oxygen injection; (iii) ETBE plus other PH; (iv) ETBE plus other PH subjected to oxygen injection. Under all conditions investigated, significant {sup 13}C-incorporation into microbial total lipid fatty acids extracted from the in situ microcosms was found, providing clear evidence of ETBE biodegradation.

  11. Effect of Ethanol and Methyl-tert-Butyl Ether on Monoaromatic Hydrocarbon Biodegradation: Response Variability for Different Aquifer Materials Under Various Electron-Accepting Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz-Aguilar, G L; Fernandez-Sanchez, J M; Kane, S R; Kim, D; Alvarez, P J

    2003-10-06

    Aquifer microcosms were used to determine how ethanol and methyl-tert-butyl ether (MtBE) affect monoaromatic hydrocarbon degradation under different electron-accepting conditions commonly found in contaminated sites experiencing natural attenuation. Response variability was investigated by using aquifer material from four sites with different exposure history. The lag phase prior to BTEX (benzene, toluene, ethylbenzene, and xylenes) and ethanol degradation was typically shorter in microcosms with previously contaminated aquifer material, although previous exposure did not always result in high degradation activity. Toluene was degraded in all aquifer materials and generally under a broader range of electron-accepting conditions compared to benzene, which was degraded only under aerobic conditions. MtBE was not degraded within 100 days under any condition, and it did not affect BTEX or ethanol degradation patterns. Ethanol was often degraded before BTEX compounds, and had a variable effect on BTEX degradation as a function of electron-accepting conditions and aquifer material source. An occasional enhancement of toluene degradation by ethanol occurred in denitrifying microcosms with unlimited nitrate; this may be attributable to the fortuitous growth of toluene-degrading bacteria during ethanol degradation. Nevertheless, experiments with flow-through aquifer columns showed that this beneficial effect could be eclipsed by an ethanol-driven depletion of electron acceptors, which significantly inhibited BTEX degradation and is probably the most important mechanism by which ethanol could hinder BTEX natural attenuation. A decrease in natural attenuation could increase the likelihood that BTEX compounds reach a receptor as well as the potential duration of exposure.

  12. Facile fabrication of safe and robust polyimide fibrous membrane based on triethylene glycol diacetate-2-propenoic acid butyl ester gel electrolytes for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • Uniform PI membranes are fabricated by electrospinning. • PI-GEL electrolyte is synthesized by incorporating TEGDA-BA copolymer. • It shows high ionic conductivities and electrochemical stabilities. • The mechanical properties of PI-GEL are highly improved. • The cells using PI-GEL demonstrate stable charge/discharge performance. - Abstract: Robust electrospun polyimide (PI) membranes are simply fabricated by polymerization of oxidianiline (ODA) and pyromellitic dianhydride (PMDA). The as-prepared PI membranes, with reliable safety (self-extinguishing) and excellent mechanical property, exhibit highly uniform morphology with an average fiber diameter ∼ 600 nm, high porosity ∼67%, high electrolyte uptake ∼534% and good relative absorption ratio ∼75% of the initial absorption (electrolyte uptake until 240 min). With the presence of triethylene glycol diacetate-2-propenoic acid butyl ester (TEGDA-BA) gel electrolytes, the resulting polyimide-gel electrolytes (PI-GEL) show a high ionic conductivity up to 2.0 × 10−3 S cm−1 at 25 °C, coupled with high electrochemical stability (>4.5 V vs. Li/Li+). The Li/PI-GEL/LiFeO4 cells demonstrate remarkably stable charge/discharge performance and excellent capacity retention of ∼146.8 mAh g−1 (0.1 C) after 100 cycles. The results suggest a facile strategy for scalable fabrication of high-performance polymer electrolyte membrane for lithium ion batteries

  13. Effect of polyacrylonitrile on triethylene glycol diacetate-2-propenoic acid butyl ester gel polymer electrolytes with interpenetrating crosslinked network for flexible lithium ion batteries

    Science.gov (United States)

    Wang, Qiujun; Song, Wei-Li; Fan, Li-Zhen; Shi, Qiao

    2015-11-01

    A new flexible gel polymer electrolytes (GPE) with interpenetrating cross-linked network is fabricated by blending long-chain polyacrylonitrile (PAN) polymer matrix and short-chain triethylene glycol diacetate-2-propenoic acid butyl ester (TEGDA-BA) framework, with the purpose of enhancing the mechanical stability of the GPE frameworks via synergistic effects of the linear polymers and crosslinked monomers. The as fabricated frameworks enable the liquid electrolytes to be firmly entrapped in the polymeric matrices, which significantly improves the mechanical bendability and interface stability of the resultant GPE. The GPE with 5 wt% PAN exhibits high ionic conductivity up to 5.9 × 10-3 S cm-1 at 25 °C with a stable electrochemical window observed (>5.0 V vs. Li/Li+). The Li|GPE|LiFePO4 half cells demonstrate remarkably stable capacity retention and rate ability during cycling tests. As expected, the LiFePO4|GPE|Li4Ti5O12 full cells also exhibit discharge capacity of 125.2 mAh g-1 coupled with high columbic efficiency greater than 98% after 100 cycles. The excellent mechanical flexibility and charge/discharge performance suggest that the GPE holds great application potential in flexible LIBs.

  14. Sonolytic and Silent Polymerization of Methacrlyic Acid Butyl Ester Catalyzed by a New Onium Salt with bis-Active Sites in a Biphasic System — A Comparative Investigation

    Directory of Open Access Journals (Sweden)

    Perumberkandgai A. Vivekanand

    2013-02-01

    Full Text Available Currently, ingenious new analytical and process experimental techniques which are environmentally benign techniques, viz., ultrasound irradiation, have become immensely popular in promoting various reactions. In this work, a novel soluble multi-site phase transfer catalyst (PTC viz., 1,4-bis-(propylmethyleneammounium chloridebenzene (BPMACB was synthesized and its catalytic efficiency was assessed by observing the kinetics of sonolytic polymerization of methacrylic acid butyl ester (MABE using potassium persulphate (PPS as an initiator. The ultrasound–multi-site phase transfer catalysis (US-MPTC-assisted polymerization reaction was compared with the silent (non-ultrasonic polymerization reaction. The effects of the catalyst and various reaction parameters on the catalytic performance were in detail investigated by following the kinetics of polymerization of MABE in an ethyl acetate-water biphasic system. From the detailed kinetic investigation we propose a plausible mechanism. Further the kinetic results demonstrate clearly that ultrasound-assisted phase-transfer catalysis significantly increased the reaction rate when compared to silent reactions. Notably, this environmentally benign and cost-effective process has great potential to be applied in various polymer industries.

  15. Equilibrium 2H/ 1H fractionations in organic molecules. II: Linear alkanes, alkenes, ketones, carboxylic acids, esters, alcohols and ethers

    Science.gov (United States)

    Wang, Ying; Sessions, Alex L.; Nielsen, Robert J.; Goddard, William A., III

    2009-12-01

    Equilibrium 2H/ 1H fractionation factors (α eq) for various H positions in alkanes, alkenes, ketones, carboxylic acids, esters, alcohols, and ethers were calculated between 0 and 100 °C using vibrational frequencies from ab initio QM calculations (B3LYP/6-311G**). Results were then corrected using a temperature-dependent linear calibration curve based on experimental data for H α in ketones ( Wang et al., 2009). The total uncertainty in reported α eq values is estimated at 10-20‰. The effects of functional groups were found to increase the value of α eq for H next to electron-donating groups, e.g. sbnd OR, sbnd OH or sbnd O(C dbnd O)R, and to decrease the value of α eq for H next to electron-withdrawing groups, e.g. sbnd (C dbnd O)R or sbnd (C dbnd O)OR. Smaller but significant functional group effects are also observed for H β and sometimes H γ. By summing over individual H positions, we estimate the equilibrium fractionation relative to water to be -90‰ to -70‰ for n-alkanes and around -100‰ for pristane and phytane. The temperature dependence of these fractionations is very weak between 0 and 100 °C. Our estimates of α eq agree well with field data for thermally mature hydrocarbons (δ 2H values between -80‰ and -110‰ relative to water). Therefore the observed δ 2H increase of individual hydrocarbons and the disappearance of the biosynthetic δ 2H offset between n-alkyl and linear isoprenoid lipids during maturation of organic matter can be confidently attributed to H exchange towards an equilibrium state. Our results also indicate that many n-alkyl lipids are biosynthesized with δ 2H values that are close to equilibrium with water. In these cases, constant down-core δ 2H values for n-alkyl lipids cannot be reliably used to infer a lack of isotopic exchange.

  16. Effect of Solvent Additives on the Solution Aggregation of Phenyl-C61-Butyl Acid Methyl Ester (PCBM)

    KAUST Repository

    Tummala, Naga Rajesh

    2015-11-24

    High-boiling-point solvent additives, employed during the solution processing of active-layer formulations, impact the efficiency of bulk hetero-junction (BHJ) organic solar cells by influencing the morphological / topological features of the multicomponent thin film. Here, we aim at a better understanding of how these additives change the aggregation landscape in the casting solution prior to film deposition via a multi-scale computational study of the aggregation phenomena of phenyl-C61-butyric-acid methyl ester (PCBM) in various solutions. The energetic landscape of PCBM-solvent / solvent-additive intermolecular interactions is evaluated at the electronic-structure level through symmetry-adapted perturbation theory to determine the nature and strength of non-covalent forces important to aggregation. Molecular dynamics simulations highlight how the choice of solvent and solvent additives control the formation of molecular aggregates. Our results indicate that high-boiling-point solvent additives change the effective interactions among the PCBM and casting-solvent molecules and alter the equilibrium PCBM aggregate sizes in solution.

  17. Selective extraction of 90Sr in urine using 4'4″(5″)di-tert-butyl dicyclohexano-18-crown-6 ether immobilized on polyacrylamide-coated magnetic nanoparticles

    International Nuclear Information System (INIS)

    4'4'(5')di-tert-butyl dicyclohexano-18-crown-6 ether was immobilized onto the surface of iron oxide magnetic nanoparticles coated with divinylbenzene-crosslinked polyacrylamide. The coated magnetic nanoparticles were successful in selectively extracting 90Sr from human urine samples, as confirmed by the liquid scintillation counting spectra. This method offers excellent repeatability for 90Sr in urine bioassay, with a relative precision of 8 % when five urine samples collected from different donors were spiked with 1.58 Bq of 90Sr and analyzed. (author)

  18. Long-term-stable ether-lipid vs conventional ester-lipid bicelles in oriented solid-state NMR: altered structural information in studies of antimicrobial peptides.

    Science.gov (United States)

    Bertelsen, Kresten; Vad, Brian; Nielsen, Erik H; Hansen, Sara K; Skrydstrup, Troels; Otzen, Daniel E; Vosegaard, Thomas; Nielsen, Niels Chr

    2011-03-01

    Recently, ether lipids have been introduced as long-term stable alternatives to the more natural, albeit easier degradable, ester lipids in the preparation of oriented lipid bilayers and bicelles for oriented-sample solid-state NMR spectroscopy. Here we report that ether lipids such as the frequently used 14-O-PC (1,2-di-O-tetradecyl-sn-glycero-3-phosphocholine) may induce significant changes in the structure and dynamics, including altered interaction between peptides and lipids relative to what is observed with the more conventionally used DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine) bilayers. Such effects are demonstrated for the antimicrobial peptide novicidin, for which 2D separate-local-field NMR and circular dichroism experiments reveal significant structural/conformational differences for the peptide in the two different lipid systems. Likewise, we observe altered secondary structure and different temperature-dependent membrane anchoring for the antimicrobial peptide alamethicin depending on whether the peptide is reconstituted into ester or ether lipids. Such observations are not particularly surprising considering the significant difference of the lipids in the phosphorus headgroup and they may provide important new insight into the delicate peptide-membrane interactions in the systems studied. In contrast, these observations reinforce the need to carefully consider potential structural changes in addition to long-term stability prior to the selection of membrane environment of membrane proteins in the analysis of their structure and dynamics. In more general terms, the results underscore the necessity in structural biology to address both the protein and its environments in studies relating structure to function. PMID:21309516

  19. Equation of state for methyl tert-butyl ether%甲基叔丁基醚的状态方程

    Institute of Scientific and Technical Information of China (English)

    周永; 吴江涛

    2012-01-01

    In this work, the equation of state for methyl tert-butyl ether (MTBE) is developed based on the experimental data in literature using the Helmholtz energy as the fundamental property with independent variables of density and temperature. Overall, the uncertainty of the equation of state is 1.0% in vapor pressure bellow 430 K and increases with temperature due to a lack of experimental data. The uncertainty in density ranges from 0. 1% in the liquid region to 1.0% elsewhere, including the critical and vapor regions. The uncertainties in the properties related to energy (such as heat capacity and sound speed) are estimated to be 0. 5%. In the critical region, the uncertainties are higher for all properties except vapor pressure. The behavior of the equation of state is reasonable within the region of validity and at higher and lower temperatures and pressures.%利用公开发表的实验数据开发了甲基叔丁基醚(MTBE)的状态方程,方程以Helmholtz自由能为显式、以温度和密度为自变量.方程计算饱和蒸气压的不确定度430 K以下为1.0%,随着温度的升高,由于缺少实验数据不确定度增大为2.0%.方程计算密度的不确定度由液相区的0.2%变到临界区和气相区的1.0%.方程计算能量相关物性(如比热容、音速)的不确定度为0.5%.临界区,除了饱和蒸气压,方程计算所有其他热力学性质的不确定度都较高.本文方程不但能准确地复现实验数据,而且方程的外推性也是合理的.

  20. Product analyses and kinetic studies on gas phase oxidation of the fuel additive ethyl tert-butyl ether and its products; Produktanalysen und Kinetikuntersuchungen der Gasphasenoxidation des Kraftstoffadditivs Ethyl-tert-butylether und seiner Produkte

    Energy Technology Data Exchange (ETDEWEB)

    Becker, K.H.; Thuener, L.

    1997-04-01

    The widespread use of the additive ETBE in gasoline leads to an increased release of this compound into the atmosphere via evaporation or exhaust fumes. In order to determine the influence of this additive on trace gas cycles it is first necessary to carry out studies on the degradation mechanisms and pertinent kinetic properties of this substance. The aim of the present study was to examine the degradation mechanisms of the fuel additive t-butyl ethyl ether under atmospheric conditions. The reactions of the main degradation products (t-butyl formiate and t-butyl acetate, together ca. 80%) were also studied in order to obtain as complete a picture of the degradation paths as possible. This was to permit an assessment of the influence of ETBE and its products on tropospheric trace gas cycles and ozone formation. [Deutsch] Bei haeufigem Zusatz von ETBE in Benzin wird diese Verbindung durch Verdampfung oder als Abgas verstaerkt in die Atmosphaere abgegeben. Um den Einfluss des Additivs auf die Spurengas-Kreislaeufe zu bestimmen, sind daher Untersuchungen noetig, um die Abbau-Mechanismen und die zugehoerigen kinetischen Daten zu ermitteln. Das Ziel dieser Arbeit ist die Untersuchung der Abbaumechanismen des Kraftstoffadditivs t-Butylethylether unter atmosphaerischen Bedingungen. Fuer eine moeglichst vollstaendige Analyse des Abbauweges werden auch die Reaktionen der Hauptabbauprodukte (t-Butylformiat und t-Butylacetat, zusammen etwa 80%) untersucht. Dadurch soll der Einfluss auf troposphaerische Spurengas-Kreislaeufe und auf die Ozonbildung von ETBE und seinen Produkten abgeschaetzt werden. (orig./SR)

  1. Prediction methods for the calculation of the flammability properties of gases and vapors: CHETAH and ASTM software. Part 1. Esters and Ethers

    International Nuclear Information System (INIS)

    After the law by decree of the 12. June 2003, N 233 (ATEX Directive) and REACH regulation (Regulation EC n. 2907/2006 of the European Parliament), several industrial fields, also not chemical, need the flammability data for the substances used. Perhaps, many of these data, especially for compounds with not common uses, are not easy to collect. It would be helpful to provide prediction methods in order to calculate these data without any experimentation that sometimes results time consuming, expensive and practically impossible for all the commercial compounds. In this research the ASTM software CHETAH (CHEmical Thermodynamic And Hazard evaluation) has been used in order to compute the lower flammability limit (Li), the limiting oxygen concentration (LOC, using nitrogen as inert gas) as a function of temperature, the adiabatic flame temperature Tflame, the fundamental burning velocity (Su), the quenching distance (Qd), the minimum ignition energy (MIE) for esters and ethers, substances highly used in industry.

  2. Chikusetsusaponin IVa Butyl Ester (CS-IVa-Be), a Novel IL6R Antagonist, Inhibits IL6/STAT3 Signaling Pathway and Induces Cancer Cell Apoptosis.

    Science.gov (United States)

    Yang, Jie; Qian, Shihui; Cai, Xueting; Lu, Wuguang; Hu, Chunping; Sun, Xiaoyan; Yang, Yang; Yu, Qiang; Gao, S Paul; Cao, Peng

    2016-06-01

    The activation of IL6/STAT3 signaling is associated with the pathogenesis of many cancers. Agents that suppress IL6/STAT3 signaling have cancer-therapeutic potential. In this study, we found that chikusetsusaponin IVa butyl ester (CS-IVa-Be), a triterpenoid saponin extracted from Acanthopanas gracilistylus W.W.Smith, induced cancer cell apoptosis. CS-IVa-Be inhibited constitutive and IL6-induced STAT3 activation, repressed STAT3 DNA-binding activity, STAT3 nuclear translocation, IL6-induced STAT3 luciferase reporter activity, IL6-induced STAT3-regulated antiapoptosis gene expression in MDA-MB-231 cells, and IL6-induced TF-1 cell proliferation. Surprisingly, CS-IVa-Be inhibited IL6 family cytokines rather than other cytokines induced STAT3 activation. Further studies indicated that CS-IVa-Be is an antagonist of IL6 receptor via directly binding to the IL6Rα with a Kd of 663 ± 74 nmol/L and the GP130 (IL6Rβ) with a Kd of 1,660 ± 243 nmol/L, interfering with the binding of IL6 to IL6R (IL6Rα and GP130) in vitro and in cancer cells. The inhibitory effect of CS-IVa-Be on the IL6-IL6Rα-GP130 interaction was relatively specific as CS-IVa-Be showed higher affinity to IL6Rα than to LIFR (Kd: 4,910 ± 1,240 nmol/L) and LeptinR (Kd: 4,990 ± 915 nmol/L). We next demonstrated that CS-IVa-Be not only directly induced cancer cell apoptosis but also sensitized MDA-MB-231 cells to TRAIL-induced apoptosis via upregulating DR5. Our findings suggest that CS-IVa-Be as a novel IL6R antagonist inhibits IL6/STAT3 signaling pathway and sensitizes the MDA-MB-231 cells to TRAIL-induced cell death. Mol Cancer Ther; 15(6); 1190-200. ©2016 AACR. PMID:26929249

  3. Synthesis, screening for antiacetylcholinesterase activity and binding mode prediction of a new series of [3-(disubstituted-phosphate)-4,4,4-trifluoro-butyl]-carbamic acid ethyl esters

    Energy Technology Data Exchange (ETDEWEB)

    Zanatta, Nilo; Marchi, Tiago M.; Bonacorso, Helio G.; Martins, Marcos A.P.; Flores, Alex F.C. [Universidade Federal de Santa Maria, RS (Brazil). Dept. de Quimica. Nucleo de Quimica de Heterociclos]. E-mail: zanatta@base.ufsm.br; Borchhardt, Deise M.; Andricopulo, Adriano D.; Salum, Livia B. [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Centro de Biotecnologia Molecular Estrutural. Lab. de Quimica Medicinal e Computacional; Carpes, Adriana D.; Schetinger, Maria R.C. [Universidade Federal de Santa Maria, RS (Brazil). Dept. de Quimica. Lab. de Enzimologia Toxicologica

    2008-07-01

    A series of nine new [3-(disubstituted-phosphate)-4,4,4-trifluoro-butyl]-carbamic acid ethyl esters (phosphate-carbamate compounds) was obtained through the reaction of (4,4,4-trifluoro-3-hydroxybut-1-yl)-carbamic acid ethyl esters with phosphorus oxychloride followed by the addition of alcohols. The products were characterized by {sup 1}H, {sup 13}C, {sup 31}P, and {sup 19}F NMR spectroscopy, GC-MS, and elemental analysis. All the synthesized compounds were screened for acetylcholinesterase (AChE) inhibitory activity using the Ellman method. All compounds containing phosphate and carbamate pharmacophores in their structures showed enzyme inhibition, being the compound bearing the diethoxy phosphate group (2b) the most active compound. Molecular modeling studies were performed to investigate the detailed interactions between AChE active site and small-molecule inhibitor candidates, providing valuable structural insights into AChE inhibition. (author)

  4. SENSORY, SYMPTOMATIC, INFLAMMATORY, AND OCULAR RESPONSES TO AND THE METABOLISM OF METHYL TERTIARY BUTYL ETHER IN A CONTROLLED HUMAN EXPOSURE EXPERIMENT

    Science.gov (United States)

    In response to elevated ambient carbon monoxide (CO) due to incomplete combustion of automotive fuels, the Clear Air Act mandates that CO reduction be obtained by adding oxygenates to the fuel (oxyfuel) in areas of non-attainment. In 1992 the addition of methyl tertiary butyl eth...

  5. 用于脱除C5及MTBE中甲醇的渗透汽化膜研究%Study on Pervaporation Membranes for Removing Methanol from C5 or Methyl Tert-butyl Ether Mixtures

    Institute of Scientific and Technical Information of China (English)

    张林; 陈欢林; 周志军; 钱锦文; 高从堦; 潘祖仁

    2003-01-01

    Several pervaporation membranes, cellulose acetate (CA), polyvinylbutyral (PVB), poly(MMA-co-AA),MMA-AA-BA, CA/PVB blend and CA/poly(MMA-co-AA) blend, were prepared, and their pervaporation properties were evaluated by separation of methanol/C5 or methanol/MTBE (methyl tert-butyl ether). The results shows that the CA composite membrane has a high separation performance (flux Jmethanol = 350 g.m-2.h-1 and separation factor α>400) for methanol/C5 mixtures, and the pervaporation characteristics of MMA-AA-BA copolymer membranes changes with the ratio of copolymer. For CA/poly(MMA-co-AA) blend membrane, the pervaporation performance is improved in comparison with CA or poly(MMA-co-AA) membrane. From the experiment of CA/PVB blend membranes for methanol/MTBE mixture, it is found that the compatibility of blends may affect the separation features of blend membrane.

  6. Bis(μ-2-tert-butyl-phenyl-imido-1:2κN:N)chlorido-2κCl-(diethyl ether-1κO)(2η-penta-methyl-cyclo-penta-dien-yl)lithiumtantalum(V).

    Science.gov (United States)

    Cole, Jacqueline M; Chan, Michael C W; Gibson, Vernon C; Howard, Judith A K

    2011-06-01

    In the title compound, [LiTa(C(10)H(15))(C(10)H(13)N)(2)Cl(C(4)H(10)O)], the Ta(V) atom is coordinated by a η(5)-penta-methyl-cyclo-penta-dienyl (Cp*) ligand, a chloride ion and two N-bonded 2-tert-butyl-phenyl-imide dianions. With respect to the two N atoms, the chloride ion and the centroid of the Cp* ring, the tantalum coordination geometry is approximately tetra-hedral. The lithium cation is bonded to both the 2-tert-butyl-phenyl-imide dianions and also a diethyl ether mol-ecule, in an approximate trigonal planar arrangement. The Ta⋯Li separation is 2.681 (15) Å. In the crystal, a weak C-H⋯Cl inter-action links the mol-ecules. When compared to the 2,6-diisopropyl-phenyl-imide analogue ('the Wigley derivative') of the title compound, the two structures are conformationally matched with an overall r.m.s. difference of 0.461Å. PMID:21754594

  7. Catabolism of methyl ter-butyl ether (MTBE): characterization of the enzymes of Mycobacterium austroafricanum IFP 2012 involved in MTBE degradation; Catabolisme du methyl tert-butyl ether (MTBE): caracterisation des enzymes impliquees dans la degradation du MTBE chez Mycobacterium austroafricanum IFP 2012

    Energy Technology Data Exchange (ETDEWEB)

    Lopes Ferreira, N.

    2005-11-15

    Methyl tert-butyl ether (MTBE) is added to gasoline to meet the octane index requirement. its solubility in water and its poor biodegradability made the use of MTBE a great environmental concern, particularly regarding aquifers. We previously isolated M austroafricanum IFP 2012 able to use MTBE as a sole source of carbon and energy and the MTBE pathway was partially characterized. In the present study, which aimed at isolating the genes involved in MTBE biodegradation in order to use them for estimation of MTBE biodegradation capacities in contaminated environment, we isolated a new M. austroafricanum strain, IFP 2015. A new degradation intermediate, the 2-methyl 1,2-propane-diol (2-M1,2-PD), the product of tert-butanol (TBA) oxidation, was identified. We also determined the enzymes induced during growth of M. austroafricanum IFP 2012 on MTBF. Then, using the tools of protein analysis and of molecular biology, we isolated and cloned the mpd genes cluster in the plasmid pCL4D. Heterologous expression of the recombinant plasmid in M smegmatis tmc2 155, showed the involvement of an 2-M1,2-PD dehydrogenase (MpdB) and a hydroxy-iso-butyr-aldehyde dehydrogenase (MpdC), encoded by mpdB and mpdC, respectively. Both enzymes were responsible for the conversion of 2-M 1,2-PD to hydroxy-isobutyric acid (HIBA). A further survey of different M austroafricanum strains, including IFP 2012, IFP 2015 and JOBS (ex-M vaccae) showed the link between the ability to grow on C{sub 2} to C{sub 16} n-alkanes and the MTBE and TBA degradation capacities. The alkB gene was partially sequenced in all these strains. Expression of alkB was demonstrated in M. austroafricanum IFP 2012 after growth on propane, hexane, hexadecane and TBA. Finally, we identified 2-propanol as the intermediate of HIBA degradation. The gene encoding the 2-propanol:p-N,N'-dimethyl-4-nitroso-aniline (NDMA) oxidoreductase was detected M austroafricanum IFP 2012. (author)

  8. Widespread occurrence of bisphenol A diglycidyl ethers, p-hydroxybenzoic acid esters (parabens), benzophenone type-UV filters, triclosan, and triclocarban in human urine from Athens, Greece.

    Science.gov (United States)

    Asimakopoulos, Alexandros G; Thomaidis, Nikolaos S; Kannan, Kurunthachalam

    2014-02-01

    Biomonitoring of human exposure to bisphenol A diglycidyl ethers (BADGEs; resin coating for food cans), p-hydroxybenzoic acid esters (parabens; preservatives), benzophenone-type UV filters (BP-UV filters; sunscreen agents), triclosan (TCS; antimicrobials), and triclocarban (TCC; antimicrobials) has been investigated in western European countries and North America. Nevertheless, little is known about the exposure of Greek populations to these environmental chemicals. In this study, 100 urine samples collected from Athens, Greece, were analyzed by liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for the determination of total concentrations of five derivatives of BADGEs, six parabens and their metabolite (ethyl-protocatechuate), five derivatives of BP-UV filters, TCS, and TCC. Urinary concentrations of BADGEs, parabens, ethyl-protocatechuate, BP-UV filters, TCS and TCC (on a volume basis) ranged 0.3-20.9 (geometric mean: 0.9), 1.6-1010 (24.2), <2-71.0 (2.1), 0.5-1120 (4.4), <0.5-2580 (8.0) and <0.5-1.9 (0.6) ng/mL, respectively. All 19 target chemicals were found in urine, and the highest detection rates were observed for methyl paraben (100%), bisphenol A bis (2,3-dihydroxypropyl) ether (90%), ethyl paraben (87%), 2,4-dihydroxybenzophenone (78%), propyl paraben (72%), and TCS (71%). Estimated daily intakes (EDIurine), calculated on the basis of the measured urinary concentrations, ranged from 0.023 μg/kg bw/day for Σ5BADGEs to 31.4 μg/kg bw/day for Σ6Parabens. PMID:24246946

  9. Use of 3H-cholesteryl linoleyl ether as a quantitative marker for loss of cholesteryl ester during regression of cholesterol-induced aortic atheromas in rabbits

    International Nuclear Information System (INIS)

    In this study, use was made of 3H-cholesteryl linoleyl ether (3H-CLE) to follow regression of aortic atheromatosis induced by feeding cholesterol to rabbits. After a 3-month induction period, the rabbits were divided into two groups with an attempt to match them by plasma cholesterol levels. They were injected with rabbit plasma labeled with 3H-CLE, and the baseline group rabbits were killed 10 to 12 days after injection. The experimental (regression) group rabbits were given rabbit chow containing 3% cholestyramine and were killed up to 330 days thereafter. Aortic 3H-CLE of both the baseline and the regression groups correlated highly with the plasma cholesterol levels at the time of injection of label. The radioactivity recovered in the aortas of the baseline and regression groups was not significantly different, indicating retention of label between day 12 and 330 days after injection. During that time, the mean aortic cholesteryl ester content decreased from 7.6 +/- 1.3 mg to 3.1 +/- 0.7 mg (p less than 0.01). The specific activity of 3H-CLE/cholesteryl ester determined in the aortic arch and the thoracic and abdominal aorta was significantly increased in all three regions examined in the regression group as compared to the baseline group. The present data show that 3H-CLE is retained in the atheromatous aorta for at least 330 days and that its use may add another dimension to the quantitative evaluation of regression of atherosclerotic lesions

  10. Effect of Naphthalene, Butylated Hydroxytoluene, Dioctyl Phthalate, and Adipic Dioctyl Ester, Chemicals Found in the Nests of the Formosan Subterranean Termite (Isoptera: Rhinotermitidae) on a Saprophytic Mucor sp.

    Science.gov (United States)

    Fungi are commonly found associated with termites and their nests. Four chemicals that have been isolated from the nests of the Formosan subterranean termite, Coptotermes formosanus Shiraki, were evaluated to determine their effect on a common nest fungus, a saprophytic Mucor sp. Butylated hydroxyto...

  11. Occurrence of phthalate diesters (phthalates), p-hydroxybenzoic acid esters (parabens), bisphenol A diglycidyl ether (BADGE) and their derivatives in indoor dust from Vietnam: Implications for exposure.

    Science.gov (United States)

    Tran, Tri Manh; Minh, Tu Binh; Kumosani, Taha A; Kannan, Kurunthachalam

    2016-02-01

    Phthalate diesters (phthalates), esters of p-hydroxybenzoic acid (parabens), and bisphenol A diglycidyl ether (BADGE) are used in personal care products, food packages, household products, or pharmaceuticals. These compounds possess endocrine-disrupting potentials and have been reported to occur in the environment. Nevertheless, no previous studies have reported the occurrence of these compounds in indoor dust from Vietnam. In this study, nine phthalates, six parabens, and four BADGEs were determined in indoor dust samples collected from Hanoi, Hatinh, Hungyen, and Thaibinh, in Vietnam. Total concentrations of phthalates, parabens, and BADGEs in indoor dust ranged from 3440 to 106,000 ng/g (median: 22,600 ng/g), 40-840 ng/g (median: 123 ng/g), and 23 to 1750 ng/g (median: 184 ng/g), respectively. Based on the measured median concentration of phthalates, parabens, and BADGEs in indoor dust, we estimated human exposure doses to these compounds through indoor dust ingestion for various age groups. The exposure doses to phthalates, parabens, and BADGEs decreased with age and ranged from 19.4 to 90.4 ng/kg-bw/d, 0.113-0.528 ng/kg-bw/d, and 0.158-0.736 ng/kg-bw/d, respectively. This is the first study on the occurrence and human exposure of phthalates, parabens, and BADGEs in indoor dust from Vietnam. PMID:26498104

  12. Formation and cleansing performance of bicontinuous microemulsions in water/poly (oxyethylene) alkyl ether/ester-type oil systems.

    Science.gov (United States)

    Aramaki, Kenji; Tawa, Kosuke; Shrestha, Lok Kumar; Iwanaga, Tetsuro; Kamada, Miho

    2013-01-01

    Phase behaviors in water/poly(oxyethylene) dodecyl ether (C₁₂EO(n), n = 4, 6, 8)/cetyl isooctanoate (CIO) systems were studied. In the C₁₂EO₆ and C₁₂EO₈ systems, self-assembled structures with positive curvatures, such as O/W microemulsions, and micellar cubic and hexagonal phases, were observed. A wider region of a lamellar liquid-crystalline phase, which included a narrow microemulsion region joined by a miscibility gap, was observed in the C₁₂EO₄ system. The structure of the microemulsion phase in the C₁₂EO₄ system was characterized by pulsed-field-gradient NMR (PFG-NMR) and small angle X-ray scattering (SAXS) techniques. PFG-NMR measurements indicated that the structure of the microemulsion was bicontinuous; both water and oil phases were continuous within the microemulsion. Pair-distance distribution function, p (r), and structure factors obtained by Generalized Indirect Fourier Transformation (GIFT) analysis of the SAXS data showed that the microemulsion domain sizes decreased with an increase in the oil content. The structure of the bicontinuous microemulsion was consistent with the results of a detergency test, in which the microemulsion samples were applied to lipstick dirt on an artificial skin plate. Detergency was observed to be better for the microemulsion at lower oil contents because of the larger oil domain size at these low concentrations. PMID:24088518

  13. Scientific Opinion on the safety and efficacy of aliphatic, alicyclic and aromatic saturated and unsaturated tertiary alcohols and esters with esters containing tertiary alcohols ethers (chemical group 6 when used as flavourings for all animal species

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2012-11-01

    Full Text Available Chemical group 6 consists of aliphatic, alicyclic and aromatic saturated and unsaturated tertiary alcohols and esters with esters containing tertiary alcohols ethers, of which 13 are currently authorised for use as flavours in food. The high use level proposed by the applicant for linalool (25 mg/kg complete feed is safe for salmonids, veal calves, cattle for fattening and pets (excluding cats without a margin of safety with the exception of dogs (SF = 1.4. The safe use level for pigs and dairy cows is 20, for piglets 12 and for poultry 10 mg/kg complete feed. The high use level of 5 mg/kg complete feed for linalyl acetate, linalyl butyrate, linalyl formate, linalyl propionate, linalyl isobutyrate, terpineol, α-terpineol and terpineol acetate and 4-terpinenol is safe for all species with a margin of safety of 1.2 to 12. For nerolidol, 2-methyl-1-phenylpropan-2-ol and 2-(4-methylphenylpropan-2-ol, the maximum safe concentration is 1 mg/kg complete feed for pigs and poultry and 1.5 mg/kg complete feed for all other species. The absence of a margin of safety would not allow the simultaneous administration in feed and water for drinking of the following compounds: linalool, nerolidol, 2-methyl-1-phenylpropan-2-ol and 2-(4methylphenylpropan-2-ol. No safety concern would arise for the consumer from the use of compounds belonging to CG 6 up to the highest safe level in feedingstuffs for all animal species. All compounds should be considered as irritants to skin, eyes and respiratory tract, and as skin sensitisers. All compounds of CG 6 are predicted to be safe to the soil compartment when used at levels safe to the target species. Using predictions based on chemical structure, 2-methyl-1-phenylpropan-2-ol and 2-(4-methylphenylpropan-2-ol were estimated to be safe to aquatic compartments. In the absence of experimental data, safety to aquatic compartments could not be established for linalyl butyrate, linalyl isobutyrate, terpineol acetate, 4

  14. γ-aminobutyric acidA (GABAA) receptor regulates ERK1/2 phosphorylation in rat hippocampus in high doses of Methyl Tert-Butyl Ether (MTBE)-induced impairment of spatial memory

    International Nuclear Information System (INIS)

    Experimental and occupational exposure to Methyl Tert-Butyl Ether (MTBE) has been reported to induce neurotoxicological and neurobehavioral effects, such as headache, nausea, dizziness, and disorientation, etc. However, the molecular mechanisms involved in MTBE-induced neurotoxicity are still not well understood. In the present study, we investigated the effects of MTBE on spatial memory and the expression and function of GABAA receptor in the hippocampus. Our results demonstrated that intraventricular injection of MTBE impaired the performance of the rats in a Morris water maze task, and significantly increased the expression of GABAA receptor α1 subunit in the hippocampus. The phosphorylation of ERK1/2 decreased after the MTBE injection. Furthermore, the decreased ability of learning and the reduction of phosphorylated ERK1/2 level of the MTBE-treated rats was partly reversed by bicuculline injected 30 min before the training. These results suggested that MTBE exposure could result in impaired spatial memory. GABAA receptor may play an important role in the MTBE-induced impairment of learning and memory by regulating the phosphorylation of ERK in the hippocampus.

  15. Volumetric and viscometric properties of binary mixtures of {methyl tert-butyl ether (MTBE) + alcohol} at several temperatures and p = 0.1 MPa: Experimental results and application of the ERAS model

    International Nuclear Information System (INIS)

    Highlights: → Binary mixtures of MTBE + alcohol have been studied. → Volumetric and viscometric properties have been determined at several temperatures. → Excess molar volumes have been used to test the applicability of the ERAS model. → The results are discussed in terms of chemical and structural effects. - Abstract: Densities and viscosities of binary mixtures of {methyl tert-butyl ether (MTBE) + methanol, or +ethanol, or +1-propanol, or +2-propanol, or +1-butanol, or +1-pentanol, or +1-hexanol} have been determined as a function of composition at several temperatures and atmospheric pressure. The temperatures studied were (293.15, 298.15, 303.15, and 308.15) K. The experimental results have been used to calculate the excess molar volume (VmE) and viscosity deviation (Δη). Both VmE and Δη values were negative over the entire range of mole fraction for all temperatures and systems studied. Moreover, the VmE values have been used to test the applicability of the Extended Real Associated Solution (ERAS) model.

  16. Radiolytic decontamination of Di-n-butyl phthalate from water

    International Nuclear Information System (INIS)

    Recently, a considerable amount of phthalic acid esters (PAE), the most widely utilized plasticizer, has been released into and polluted the environment. Since their toxicity and teratogenicity, although fairly low, to experimental animals have recently been shown, the removal of them from the environment, especially from the drinking water, is desirable. As an attempt for the removal, the radiolytic degradation of 7-14C-di-n-butyl phthalate (14C-DBP) in water was investigated at several pHs. Approximately 50% of 14C-DBP (1 ppm aqueous solution) was decomposed by 60Co γ-irradiation to a dose of 3 x 104 rad at pH 7 and the main product was mono-n-butyl phthalate (MBP). At pHs 3 and 11 14C-DBP was more easily radiolyzed and converted to ether-soluble compounds other than MBP or phthalic acid (PA). By irradiation to 106 rad 14C-DBP as well as 14C-MBP and 14C-PA, at pH value tested, was almost completely decomposed to volatile or water-soluble substances of possibly low molecular weight. These findings suggest that the γ-irradiation is effective to make the PAE-polluted water clean. (auth.)

  17. Bis(μ-2-tert-butyl­phenyl­imido-1:2κ2 N:N)chlorido-2κCl-(diethyl ether-1κO)(2η5-penta­methyl­cyclo­penta­dien­yl)lithiumtantalum(V)

    OpenAIRE

    Jacqueline M. Cole; Michael C. W. Chan; Gibson, Vernon C.; Judith A. K. Howard

    2011-01-01

    In the title compound, [LiTa(C10H15)(C10H13N)2Cl(C4H10O)], the TaV atom is coordinated by a η5-penta­methyl­cyclo­penta­dienyl (Cp*) ligand, a chloride ion and two N-bonded 2-tert-butyl­phenyl­imide dianions. With respect to the two N atoms, the chloride ion and the centroid of the Cp* ring, the tantalum coordination geometry is approximately tetra­hedral. The lithium cation is bonded to both the 2-tert-butyl­phenyl­imide dianions and also a diethyl ether mol­ecule, in an approximate trigonal...

  18. EFSA ; Scientific Opinion on Flavouring Group Evaluation 67, Revision 1 (FGE.67Rev.1): Consideration of 40 furan-substituted aliphatic hydrocarbons, alcohols, aldehydes, ketones, carboxylic acids and related esters, sulfides, disulfides and ethers evaluated by JECFA at the 65th meeting (JECFA, 2006

    DEFF Research Database (Denmark)

    Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister; Lund, Pia; Binderup, Mona-Lise

    evaluation is necessary, as laid down in Commission Regulation (EC) No 1565/2000. The present consideration concerns a group of 33 furan-substituted aliphatic hydrocarbons, alcohols, aldehydes, ketones, carboxylic acids and related esters, sulfides, disulfides and ethers evaluated by the JECFA. In the...

  19. Mode of action of ethyl tertiary-butyl ether hepatotumorigenicity in the rat: Evidence for a role of oxidative stress via activation of CAR, PXR and PPAR signaling pathways

    Energy Technology Data Exchange (ETDEWEB)

    Kakehashi, Anna, E-mail: anna@med.osaka-cu.ac.jp [Department of Pathology, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585 (Japan); Hagiwara, Akihiro; Imai, Norio [DIMS Institute of Medical Science, Inc., 64 Goura, Nishiazai, Azai-cho, Ichinomiya, Aichi 491-0113 (Japan); Nagano, Kasuke [Nagano Toxicologic-Pathology Consulting, Ochiai, Hadano, Kanagawa 257-0025 (Japan); Nishimaki, Fukumi [Biofuel Assessment Group, New Fuels Dept., Japan Petroleum Energy Center (JPEC), 4-3-9 Toranomon, Minato-ku, Tokyo 105-0001 (Japan); Banton, Marcy [Toxicology and Risk Assessment, LyondellBasell Industries, LyondellBasell Corporate HSE/Product Safety, One Houston Center, Suite 700, 1221 McKinney Street, Houston, TX 770 10 (United States); Wei, Min [Department of Pathology, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585 (Japan); Fukushima, Shoji [Department of Pathology, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585 (Japan); Japan Bioassay Research Center, Japan Industrial Safety and Health Association, 2445 Hirasawa, Hadano, Kanagawa 257-0011 (Japan); Wanibuchi, Hideki [Department of Pathology, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585 (Japan)

    2013-12-01

    To elucidate possible mode of action (MOA) and human relevance of hepatotumorigenicity in rats for ethyl tertiary-butyl ether (ETBE), male F344 rats were administered ETBE at doses of 0, 150 and 1000 mg/kg body weight twice a day by gavage for 1 and 2 weeks. For comparison, non-genotoxic carcinogen phenobarbital (PB) was applied at a dose of 500 ppm in diet. Significant increase of P450 total content and hydroxyl radical levels by low, high doses of ETBE and PB treatments at weeks 1 and 2, and 8-OHdG formation at week 2, accompanied accumulation of CYP2B1/2B2, CYP3A1/3A2 and CYP2C6, and downregulation of DNA oxoguanine glycosylase 1, induction of apoptosis and cell cycle arrest in hepatocytes, respectively. Up-regulation of CYP2E1 and CYP1A1 at weeks 1 and 2, and peroxisome proliferation at week 2 were found in high dose ETBE group. Results of proteome analysis predicted activation of upstream regulators of gene expression altered by ETBE including constitutive androstane receptor (CAR), pregnane-X-receptor (PXR) and peroxisome proliferator-activated receptors (PPARs). These results indicate that the MOA of ETBE hepatotumorigenicity in rats may be related to induction of oxidative stress, 8-OHdG formation, subsequent cell cycle arrest, and apoptosis, suggesting regenerative cell proliferation after week 2, predominantly via activation of CAR and PXR nuclear receptors by a mechanism similar to that of PB, and differentially by activation of PPARs. The MOA for ETBE hepatotumorigenicity in rats is unlikely to be relevant to humans. - Highlights: • We focus on MOA and human relevance of hepatotumorigenicity in rats for ETBE. • ETBE was administered to F344 rats for 1 and 2 weeks. • Oxidative stress formation, proliferation and apoptosis in the liver are analyzed. • ETBE-induced changes of gene and protein expression in the liver are examined. • The effects are compared with those induced by non-genotoxic carcinogen PB.

  20. Mode of action of ethyl tertiary-butyl ether hepatotumorigenicity in the rat: Evidence for a role of oxidative stress via activation of CAR, PXR and PPAR signaling pathways

    International Nuclear Information System (INIS)

    To elucidate possible mode of action (MOA) and human relevance of hepatotumorigenicity in rats for ethyl tertiary-butyl ether (ETBE), male F344 rats were administered ETBE at doses of 0, 150 and 1000 mg/kg body weight twice a day by gavage for 1 and 2 weeks. For comparison, non-genotoxic carcinogen phenobarbital (PB) was applied at a dose of 500 ppm in diet. Significant increase of P450 total content and hydroxyl radical levels by low, high doses of ETBE and PB treatments at weeks 1 and 2, and 8-OHdG formation at week 2, accompanied accumulation of CYP2B1/2B2, CYP3A1/3A2 and CYP2C6, and downregulation of DNA oxoguanine glycosylase 1, induction of apoptosis and cell cycle arrest in hepatocytes, respectively. Up-regulation of CYP2E1 and CYP1A1 at weeks 1 and 2, and peroxisome proliferation at week 2 were found in high dose ETBE group. Results of proteome analysis predicted activation of upstream regulators of gene expression altered by ETBE including constitutive androstane receptor (CAR), pregnane-X-receptor (PXR) and peroxisome proliferator-activated receptors (PPARs). These results indicate that the MOA of ETBE hepatotumorigenicity in rats may be related to induction of oxidative stress, 8-OHdG formation, subsequent cell cycle arrest, and apoptosis, suggesting regenerative cell proliferation after week 2, predominantly via activation of CAR and PXR nuclear receptors by a mechanism similar to that of PB, and differentially by activation of PPARs. The MOA for ETBE hepatotumorigenicity in rats is unlikely to be relevant to humans. - Highlights: • We focus on MOA and human relevance of hepatotumorigenicity in rats for ETBE. • ETBE was administered to F344 rats for 1 and 2 weeks. • Oxidative stress formation, proliferation and apoptosis in the liver are analyzed. • ETBE-induced changes of gene and protein expression in the liver are examined. • The effects are compared with those induced by non-genotoxic carcinogen PB

  1. A Comparison of Effects of Ambient Pressure on the Atomization Performance of Soybean Oil Methyl Ester and Dimethyl Ether Sprays Comparaison des effets de la pression ambiante sur l’atomisation en “spray” de methylester d’huile de soja et de dimethyléther

    OpenAIRE

    Kim H.J.; Park S.H.; Chon M.S.; Lee C. S.

    2010-01-01

    The purpose of this study is the experimental investigation of Soybean oil Methyl Ester (SME) and DiMethyl Ether (DME) spray characteristics injected through the common-rail injection system under various ambient pressures. A high pressure chamber that can be pressurized up to 4 MPa was utilized for a change of ambient pressure. In order to compare the spray development and atomization characteristics, the images of SME and DME were obtained by using a high speed camera with two metal ha...

  2. EXPERIMENTAL INVESTIGATIONS OF REAL TIME SECONDARY CO-INJECTION OF WATER – DIETHYL ETHER SOLUTION IN DI-DIESEL ENGINE FUELLED WITH PALM KERNEL METHYL ESTER

    Directory of Open Access Journals (Sweden)

    Y. V. V. SATYANARAYANAMURTHY

    2012-12-01

    Full Text Available In this investigation tests were conducted on single cylinder diesel engine fuelled with neat diesel and biodiesel palm kernel methyl ester as a base line fuel with secondary injection of Water-DEE solution through the inlet manifold. A real time control systems consists of electronic unit pump that delivers 5% to 25% vol. Water-DEE solution through injector tip mounted nearer to the inlet manifold under a pressure of 3 kgf/cm2. NOx emissions reduced to a level of 500 ppm with simultaneous reduction of soot especially for PKME. However for 15% vol. of Water-DEE injection the HC emissions are closely tallying with that of neat diesel. A global overview of the results has shown that the 15% Water-DEE solution is the optimal blend based on performance and emission characteristics.

  3. The preparation and characterization of a novel biodiesel named curcas oil diethylene glycol ether ester%一种含醚新型生物柴油的制备与表征

    Institute of Scientific and Technical Information of China (English)

    蒋大勇

    2012-01-01

    以精制麻风树油、甲醇和二乙二醇甲醚为反应物,以KOH为催化剂,制备出一种高含氧量的新型生物柴油——麻风树油二乙二醇甲醚酯.通过正交试验,确定了其最佳合成条件是醇油物质的量比为6∶1,催化剂用量为原料油质量的1.2%,反应温度为65℃,反应时间为30 min.通过FT-IR和1H-NMR分析并验证了产物的分子结构,测试了该生物柴油及其与0#柴油混合的燃料理化性质,包括油溶性、烟点、运动粘度、凝点、闭杯闪点;在相同测试条件下,比较其与伊柴油、麻风树油甲酯的碳烟排放情况.结果表明,麻风树油二乙二醇甲醚酯具有较高的含氧量,其理化性能和排放性能良好,既可以作为柴油添加剂,也可以代替柴油单独进行使用,具有一定的推广应用价值.%In this paper, a novel biodiesel named curcas oil diethylene glycol ether esters (GDGEE) with higher oxygen content was prepared by refined curcas oil, methanol and ethylene glycol monomethyl ether as the reaction and KOH as catalyst., The optimum synthesis conditions were determined by orthogonal test. The molar ratio of methanol to oil was 6:1, catalyst amount was 1.2% of feedstock quality, reaction temperature was 65 ℃, reaction time was 30 minutes. FT-IR and IH-NMR were used to analysis and validate the molecular structure of curcas oil diethylene glycol ether esters. The physical and chemical properties of GDGEE and its blends with 0# diesel oil were tested by the national standard method. The physical and chemical properties include oil soluble, smoke point, kinematic viscosity, freezing point and closed flash point. At last, smoke emission were test among GDGEE, curcas oil methyl and 0# diesel in the same diesel engine. The results confirm that GDGEE owns the higher oxygen content, good physochemical and emission properties, which can be used as diesel fuel additives or also be used instead of diesel fuel alone. A certain application

  4. 40 CFR 799.1560 - Diethylene glycol butyl ether and diethylene glycol butyl ether acetate.

    Science.gov (United States)

    2010-07-01

    ... fixative to ensure that lung structure is maintained (perfusion with the fixative is considered to be an... lesions in control tissue shall also be noted. (ii) Reporting requirements. (A) The subchronic test shall.../day, 5 days/week for a 90-day period. (iii) Clearing and embedding. After dehydration,...

  5. tert-Butyl 1-hydroxypiperidine-2-carboxylate

    Directory of Open Access Journals (Sweden)

    Oliver Brücher

    2011-08-01

    Full Text Available The title compound, C10H19NO3, is a disubstituted piperidine bearing substituents in two equatorial positions. One of the substituents is a hydroxy group bound to nitrogen and the second a tert-butyl ester group bound to the carbon next to the endocyclic nitrogen. Enantiomers of the title compound form hydrogen-bridged dimers across a center of inversion.

  6. A multi-class bioanalytical methodology for the determination of bisphenol A diglycidyl ethers, p-hydroxybenzoic acid esters, benzophenone-type ultraviolet filters, triclosan, and triclocarban in human urine by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Asimakopoulos, Alexandros G; Wang, Lei; Thomaidis, Nikolaos S; Kannan, Kurunthachalam

    2014-01-10

    A liquid-liquid extraction (LLE; ethyl acetate) protocol, followed by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) methodology, was developed for the determination of 19 compounds, including bisphenol A diglycidyl ethers (BADGEs; industrial ethers), benzophenone-type UV filters (BP-UV filters; precursors and metabolites), p-hydroxybenzoic acid esters (parabens; preservatives), triclosan (TCS) and triclocarban (TCC) in human urine. Urine specimens were enzymatically deconjugated with β-glucuronidase (from Helix pomatia) and extracted by a LLE procedure for the measurement of total concentrations (i.e., free+conjugated forms) of target analytes. Absolute recoveries of BADGEs, BP-UV filters, parabens, TCS and TCC ranged 25-135%, 84-125%, 52-126%, 75-118% and 90-124%, respectively. Method precision (absolute values; N=5 replicate analyses at the fortification level of 10 ng, k=5 days) ranged from 5.8 (ethyl paraben) to 24.0% (TCS). The limits of quantification (LOQs) varied depending on the target compound and generally ranged from 0.2 to 2.0 ng/mL. The matrix effects ranged from +11 (2,3,4-trihydroxybenzophenone) to -86% (2,4-dihydroxybenzophenone). A total of 30 urine specimens collected from Athens, Greece, were analyzed for the 19 target compounds to demonstrate the applicability of the developed method. The concentrations of target chemicals in urine were presented on volume-, specific gravity (SG)-, and creatinine-normalization bases. MeP, EtP, PrP, OH-EtP, BADGE·2H2O, BP-1 and TCS were found frequently in urine at concentrations in the range of 2.7-436 ng/mL, <0.5-25.4 ng/mL, <0.5-575 ng/mL, <2-18.4 ng/mL, <0.5-13.8 ng/mL, <1-14.6 ng/mL and <0.5-95.3 ng/mL, respectively. PMID:24315674

  7. Degradace methyl tert-butyl etheru (MTBE) v bioreaktoru.

    Czech Academy of Sciences Publication Activity Database

    Lehnert, Radek; Gavlasová, Pavla; Kuncová, Gabriela; Bolyó, Juraj

    Bratislava: -, 2007, s. 225-226. [Zjazd chemikov /59./. Tatranské Matliare, Vysoké Tatry (SK), 02.09.2007-06.09.2007] R&D Projects: GA ČR(CZ) GA104/05/2637 Institutional research plan: CEZ:AV0Z40720504 Keywords : biodegradation * methyl terc-butyl ether (MTBE) Subject RIV: CE - Biochemistry

  8. Simulación del Proceso de Producción del Éter Etil Tert-Butílico (ETBE: Influencia de la Relación Etanol/Isobuteno Simulation of Production Process for Ethyl Tert-Butyl Ether (ETBE: Influence of the Ethanol/Isobutene Ratio

    Directory of Open Access Journals (Sweden)

    P.A. Dávila

    2004-01-01

    Full Text Available Este trabajo describe una metodología que combina el diseño conceptual y la simulación de procesos para determinar la influencia de la relación molar de alimentación etano/isobuteno sobre la selectividad hacia éter etil tert-butílico. El diseño conceptual de la columna de destilación se basó en un método gráfico de curvas de residuo y permitió determinar los esquemas de separación factibles y maximizar la concentración de éter en los productos de fondo de la columna de destilación. La simulación del proceso permitió determinar las condiciones de operación y los parámetros de diseño de los reactores y de la columna de destilación. Se concluye que la metodología disminuye drásticamente el tiempo necesario para obtener resultados con un simulador de procesosThis work describes a methodology which combines conceptual design and process simulation to determine the influence of the molar feed ratio of ethanol/isobutene on tert-butyl ethyl ether selectivity. The conceptual design of distillation columns was based on the residue curve map and it allowed determination of feasible separation schemes and maximization of the concentration of ether in the stream bottom of the distillation column. Simulation of the process has allowed determining the operating variables and design parameters for the reactors and the distillation column. It is concluded that this methodology significantly reduces the time required to obtain results with a process simulator

  9. New and extended parameterization of the thermodynamic model AIOMFAC: calculation of activity coefficients for organic-inorganic mixtures containing carboxyl, hydroxyl, carbonyl, ether, ester, alkenyl, alkyl, and aromatic functional groups

    Directory of Open Access Journals (Sweden)

    A. Zuend

    2011-09-01

    Full Text Available We present a new and considerably extended parameterization of the thermodynamic activity coefficient model AIOMFAC (Aerosol Inorganic-Organic Mixtures Functional groups Activity Coefficients at room temperature. AIOMFAC combines a Pitzer-like electrolyte solution model with a UNIFAC-based group-contribution approach and explicitly accounts for interactions between organic functional groups and inorganic ions. Such interactions constitute the salt-effect, may cause liquid-liquid phase separation, and affect the gas-particle partitioning of aerosols. The previous AIOMFAC version was parameterized for alkyl and hydroxyl functional groups of alcohols and polyols. With the goal to describe a wide variety of organic compounds found in atmospheric aerosols, we extend here the parameterization of AIOMFAC to include the functional groups carboxyl, hydroxyl, ketone, aldehyde, ether, ester, alkenyl, alkyl, aromatic carbon-alcohol, and aromatic hydrocarbon. Thermodynamic equilibrium data of organic-inorganic systems from the literature are critically assessed and complemented with new measurements to establish a comprehensive database. The database is used to determine simultaneously the AIOMFAC parameters describing interactions of organic functional groups with the ions H+, Li+, Na+, K+, NH4+, Mg2+, Ca2+, Cl, Br, NO3, HSO4, and SO42−. Detailed descriptions of different types of thermodynamic data, such as vapor-liquid, solid-liquid, and liquid-liquid equilibria, and their use for the model parameterization are provided. Issues regarding deficiencies of the database, types and uncertainties of experimental data, and limitations of the model, are discussed. The challenging parameter optimization problem is solved with a novel combination of powerful global minimization

  10. New and extended parameterization of the thermodynamic model AIOMFAC: calculation of activity coefficients for organic-inorganic mixtures containing carboxyl, hydroxyl, carbonyl, ether, ester, alkenyl, alkyl, and aromatic functional groups

    Directory of Open Access Journals (Sweden)

    A. Zuend

    2011-05-01

    Full Text Available We present a new and considerably extended parameterization of the thermodynamic activity coefficient model AIOMFAC (Aerosol Inorganic-Organic Mixtures Functional groups Activity Coefficients at room temperature. AIOMFAC combines a Pitzer-like electrolyte solution model with a UNIFAC-based group-contribution approach and explicitly accounts for interactions between organic functional groups and inorganic ions. Such interactions constitute the salt-effect, may cause liquid-liquid phase separation, and affect the gas-particle partitioning of aerosols. The previous AIOMFAC version was parameterized for alkyl and hydroxyl functional groups of alcohols and polyols. With the goal to describe a wide variety of organic compounds found in atmospheric aerosols, we extend here the parameterization of AIOMFAC to include the functional groups carboxyl, hydroxyl, ketone, aldehyde, ether, ester, alkenyl, alkyl, aromatic carbon-alcohol, and aromatic hydrocarbon. Thermodynamic equilibrium data of organic-inorganic systems from the literature are critically assessed and complemented with new measurements to establish a comprehensive database. The database is used to determine simultaneously the AIOMFAC parameters describing interactions of organic functional groups with the ions H+, Li+, Na+, K+, NH4+, Mg2+, Ca2+, Cl, Br, NO3, HSO4, and SO42−. Detailed descriptions of different types of thermodynamic data, such as vapor-liquid, solid-liquid, and liquid-liquid equilibria, and their use for the model parameterization are provided. Issues regarding deficiencies of the database, types and uncertainties of experimental data, and limitations of the model, are discussed. The challenging parameter optimization problem is solved with a novel combination of powerful global minimization

  11. 端羟基聚丁二烯改性聚醚酯弹性体的合成与表征%Synthesis and Characteristics of Multiblock Terpoly(Ester-Ether-Butadiene) Elastomers

    Institute of Scientific and Technical Information of China (English)

    宋传江; 彭军; 张英伟; 王文志; 黄自华

    2013-01-01

    Terpoly (ester-ether-butadiene) (PBT-co-PTMG/HTPB) was prepared by melt poly-condensation with dimethyl terephthalate (DMT),1,4-butandiol (BD),poly (tetramethylene-oxide glycol) (PTMG) and hydroxyl terminated polybutadiene (HTPB).The chemical structure and molecular weight of the polymers were presented by FT-IR,1H-NMR and GPC.The thermal properties and the physical and mechanical properties were measured.The results show that molecular weights of PBT-co-PTMG/HTPB increase with the content of HTPB increasing,and the maximum molecular weight is more than 8 million.The glass transition temperature moves from-25 ℃ down to -65 ℃ due to HTPB units in the soft segments.It represents the nice resistance to low temperature.Both the tensile strength and elongation at break increase with the content of HTPB when the mass fraction of HTPB is below 10 %,but decrease while the mass fraction of HTPB concentration is higher than 10 % in PBT-co-PTMG/HTPB.%以对苯二甲酸二甲酯(DMT)、1,4丁二醇(BD)、聚四氢呋喃醚(PTMG)和端羟基聚丁二烯(HTPB)为原料,采用熔融缩聚方法一步合成了一系列端羟基聚丁二烯改性的聚醚酯弹性体(PBT-co-PTMG/HTPB).通过红外、核磁和凝胶色谱等分析方法对其分子结构和分子量进行了表征;测定了聚合物的热性能和物理力学性能.结果发现,随着PBT-co-PTMG/HTPB共聚物中端羟基聚丁二烯含量的增加,数均分子量逐渐增大,最高突破8万;玻璃化转变温度由-25℃降低到-65℃,耐低温性能得到明显改善;共聚物力学性能测试结果表明,当HTPB的质量分数在10%以下时,其强度和断裂伸长率随着HTPB含量的增加而变大,但是质量分数超过10%以后,材料的强度和断裂伸长率随其含量的增加而变小.

  12. Determination of Methyl Tert-Butyl Ether in Surface Water of Huizhou City Using the Method of SPME-Headspace-GC-MS-SIM%固相微萃取-GC-MS-SIM法监测惠州市地表水中MTBE的污染状况

    Institute of Scientific and Technical Information of China (English)

    王希在; 奉夏平; 闻环

    2009-01-01

    采用固相微萃取(SPME)-顶空采样-气相色谱-质谱联用选择离子检测法(GC-MS-SIM)测定水中微量的甲基叔丁基醚.最优化实验条件为:使用75μm Carboxen/PDMS固相微萃取纤维,30℃搅拌条件下,加入20%氯化钠进行盐析.检出限为0.05μg/L,相对标准偏差为2.75%(n=8),重现性较好,样品的加标回收率在82%-120%之间.对惠州市市区地表水中MTBE的污染状况进行了监测,结果表明惠州市汽油油罐附近地表水中MTBE含量未超过美国环保局(EPA)规定最低限,居民区地表水中MTBE含量未检出,符合环保和健康要求.%Trace methyl tert-butyl ether (MTBE) in surface water was determined using the method of solid-phase micro extraction (SPME)-headspaee-GC-MS-SIM. The detection limit was 0.05μg/L, and the relative standard deviation was 2.75 %. The recoveries with standard addition were 82%-120%. We have studied the MTBE polution problem in surface water of Huizhou. The result suggested that MTBE content in surface water of Huizhou was not beyond EPA standard limits.

  13. Bismuth-based cyclic synthesis of 3,5-di-tert-butyl-4-hydroxybenzoic acid via the oxyarylcarboxy dianion, (O2CC6H2(t)Bu2O)2-.

    Science.gov (United States)

    Kindra, Douglas R; Evans, William J

    2014-02-28

    3,5-Di-tert-butyl-4-hydroxybenzoic acid can be made under mild conditions in a cyclic process from carbon dioxide and 3,5-di-tert-butyl-4-phenol using bismuth-based C-H bond activation and CO2 insertion chemistry starting with the Bi(3+) complex, Ar'BiCl2, of the NCN pincer ligand, Ar' = 2,6-(Me2NCH2)2C6H3. Complexes of the recently discovered oxyaryl dianion, (C6H2(t)Bu2-3,5-O-4)(2-), and the oxyarylcarboxy dianion, [O2C(C6H2(t)Bu2-3,5-O-4)](2-), are intermediates in the process. Further studies of the oxyarylcarboxy dianion in Ar'Bi[O2C(C6H2(t)Bu2-3,5-O-4)-κ(2)O,O'], show that it undergoes decarboxylation upon reaction with I2 and it reacts with trimethylsilyl chloride to produce the trimethylsilyl ether of the trimethylsilyl ester of 3,5-di-tert-butyl-4-hydroxybenzoic acid and the Ar'BiCl2 starting material. PMID:24336959

  14. The First Example of Cation Radical Induced Ether Cleavage of Benzyl Phenyl Ether

    International Nuclear Information System (INIS)

    A thermally stable benzyl phenyl ether has been shown to cleavage under mild conditions. The new reaction described herein further expands the chemistry of the ether cleavage by cation radicals. Over the last several years, our lab has discovered cation radical-induced oxidative C-O bond cleavages such as carbonates (eq 1), carbamates (eq 2), peroxides (eq 3), and alcohols (eq 4), where R is either tert-butyl or benzyl. It was recognized from those reactions that carbocationic chemistry with C-O bond cleavages was predominant, with a 2:1 stoichiometry of Th+·:oxidized molecules

  15. Synthesis of 4-Tert-butyl Phenol Glycidyl Ether Acrylate and Its Application in UV-curable Coating%叔丁基酚缩水甘油醚丙烯酸酯的合成及其在紫外光固化涂料中的应用

    Institute of Scientific and Technical Information of China (English)

    邓冲; 黄笔武; 周宽; 程桂亮; 胡秋发; 谌伟庆

    2013-01-01

    A novel reactive diluent was synthesized with 4-tert-butyl phenol glycidyl ether and acrylic acid as the main materials,triphenyl phosphine as the catalyst,and p-hydroxyanisole as the inhibitor.By investigating the reaction conversion,the color of product,and the viscosity of the system,the experiment results showed that the optimum conditions were as followings:the reaction temperature was 100-110 ℃,triphenyl phosphine mass fraction was 0.7%-0.9%,p-hydroxyanisole mass fraction was 0.2%-0.3%.The UV-curing coating was prepared with synthesized reactive diluent and the photoinitiator and bisphenol-A epoxy resin.The tensile,hardness and flexibility test were performed for the UV-cured films.The results showed that the coating had good mechanical and thermal properties.%以叔丁基酚缩水甘油醚和丙烯酸为主要原料,三苯基膦为催化剂,对羟基苯甲醚为阻聚剂,合成一种新型的活性稀释剂——叔丁基酚缩水甘油醚丙烯酸酯.通过对反应时间、反应温度、反应转化率、产物色泽和体系黏度等考察,得出较佳反应条件:温度为100~110℃,三苯基膦的质量分数为0.7%~0.9%,对羟基苯甲醚质量分数为0.2%~0.3%.将合成的活性稀释剂和光引发剂加入到双酚A型环氧丙烯酸酯树脂中配成紫外光固化涂料,对涂膜进行了拉伸、硬度、柔韧性等测试.结果表明:此预聚物配成的涂料具有较好的力学和热性能.

  16. The solubility and environmental characteristics of diesel ethers

    International Nuclear Information System (INIS)

    Concern over diesel particulate emissions has been ongoing for the past 2 decades, and a number of agencies have shown that adding ethers to diesel engines can reduce these particulates. However, the exact mechanism is not known. Methyl tert-butyl ether (MTBE) has been used for several years to improve the performance of gasoline engines. MTBE is very soluble in water and leaches out of the gasoline and into groundwater very easily. MTBE is being phased out due to this problem. This paper presented the results of a project initiated to evaluate candidate ethers for their solubility in water as well as other environmental characteristics. The ethers may also have the potential for reducing the emissions from diesel engines. Thirty-four ethers were tested for solubility, aquatic toxicity and biological oxygen demand. The tests were conducted due to concerns that MTBE has been shown to cause contamination as a result of its high solubility. The study focused on screening potential diesel ethers for a variety of acceptability criteria such as solubility, aquatic toxicity and degradation potential. A review of measuring methods, materials and instrumentation procedures was presented, along with solubility measurements. The stoichiometry and physical properties of petroleum ethers were also provided as well as test procedures for aquatic toxicity and microtox. A generalized property prediction model was presented. It was concluded that the properties, toxicity and degradation of the ethers vary widely. Solubility correlates with the structure of the ethers: di and tri-ethers are very soluble and any methyl ether also has high solubility. Biochemical oxygen testing of all tested ethers was low, indicating a low breakdown with typical bacterial cultures. The aquatic toxicity of the ethers is variable and correlates inversely with the solubility. The higher the solubility, the lower the toxicity. 24 refs., 10 tabs

  17. Transdermal Uptake of Diethyl Phthalate and Di(n-butyl) Phthalate Directly from Air: Experimental Verification

    OpenAIRE

    Weschler, Charles J.; Bekö, Gabriel; Koch, Holger M.; Salthammer, Tunga; Schripp, Tobias; Toftum, Jørn; Clausen, Geo

    2015-01-01

    Background Fundamental considerations indicate that, for certain phthalate esters, dermal absorption from air is an uptake pathway that is comparable to or greater than inhalation. Yet this pathway has not been experimentally evaluated and has been largely overlooked when assessing uptake of phthalate esters. Objectives This study investigated transdermal uptake, directly from air, of diethyl phthalate (DEP) and di(n-butyl) phthalate (DnBP) in humans. Methods In a series of experiments, six h...

  18. Draft Genome Sequence of Sphingobium yanoikuyae TJ, a Halotolerant Di-n-Butyl-Phthalate-Degrading Bacterium

    Science.gov (United States)

    Jin, Decai; Zhu, Ying; Wang, Xinxin; Kong, Xiao; Liu, Huijun; Wang, Yafeng

    2016-01-01

    Sphingobium yanoikuyae TJ is a halotolerant di-n-butyl-phthalate-degrading bacterium, isolated from the Haihe estuary in Bohai Bay, Tianjin, China. Here, we report the 5.1-Mb draft genome sequence of this strain, which will provide insights into the diversity of Sphingobium spp. and the mechanism of phthalate ester degradation in the estuary. PMID:27313307

  19. Fatty Acid Methyl Esters as Biosolvents of Epoxy Resins: A Physicochemical Study

    OpenAIRE

    Medina-González, Yaocihuatl; De Caro, Pascale; Thiebaud-Roux, Sophie; Lacaze-Dufaure, Corinne

    2007-01-01

    The C8 to C18 fatty acid methyl esters (FAME) have been compared as solvents for two epoxy resin pre-polymers, bisphenol A diglycidyl ether (DGEBA) and triglycidyl paminophenol ether (TGPA). It was found that the solubilization limits vary according to the ester and that methyl caprylate is the best solvent of both resins. To explain these solubility performances, physical and chemical properties of FAME were studied, such as the Hansen parameters, viscosity, binary diffusion coefficient and ...

  20. Catalytic synthesis of butyric esters with TiSiW12O40/TiO2

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The catalytic activities of TiSiW12O40/TiO2 in synthesizing ethyl ester, propyl ester, n-butyl ester, and amyl esterwere reported. It was demonstrated that TiSiW12O40/TiO2is an excellent catalyst. Various factors concemed with esterifica-tion were investigated. The optimum conditions were found: the mole ratio of alcohol to acid is 1.3:1, the mass ratio ofcatalyst to reactants is 1.5%, and the reaction time is 1.0 h. Under the optimum conditions, the yields are 88.0% for ethylester, 94.5% for propyl ester, 98.6% for n-butyl ester, 99.1% for n-amyl ester, and 96.7% for iso-amyl ester, respectively.

  1. 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

    Anaerobic biodegradation of methyl tert-butyl ether (MTBE) using electron acceptors such as nitrate, Fe(III), sulfate and bicarbonate, may be more cost effective and feasible compared to aerobic treatment methods, for dealing with the MTBE problem. Currently. there are a few reports in the...... 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...

  2. Process for producing cyclic ethers from lactones

    International Nuclear Information System (INIS)

    Cyclic ethers are produced from lactones by a process which comprises directly synthesizing cyclic ethers by the reduction of the carbonyl radicals of lactones with trichlorosilane either by the action of ionizing, visible, or ultraviolet radiations, or alternately in the presence of free radical initiators. For instance, gamma-butyl lactone mixed with trichlorosilane yields 82% of tetrahydrofuran when only irradiated with gamma-rays, whereas it yields 94% of tetrahydrofuran when exposed to ultraviolet radiations in the presence of a little amount of peroxide. Such a high yield reveals that the ring opening reaction and the ring closing reaction are not continuous, but are chain reactions in which carbonyl radicals are selectively reduced to methylene radicals without cutting the backbone structure. In one embodiment, lactone and trichlorosilane were de-aired by the vacuum refrigeration method respectively, and after being mixed in the proportion of 4:1 in a tube they were exposed to gamma-rays from a Co-60 source at room temperature at a dose rate of 3 x 105 rad/hr. In another embodiment, a de-aired mixture of lactone and ditertiary butyl peroxide with de-aired trichlorosilane in a tube were exposed to a high voltage mercury lamp for 2 hours. Ninety four percent of gamma-tetrahydrofuran, 92.2% of valerolactone tetrahydropyran or 95.7% of caprolactone hexamethylene oxide were obtained. (Iwakiri, K.)

  3. Oxidative coupling between C(sp(2))-H and C(sp(3))-H bonds of indoles and cyclic ethers/cycloalkanes.

    Science.gov (United States)

    Yang, Qingjing; Choy, Pui Ying; Wu, Yinuo; Fan, Baomin; Kwong, Fuk Yee

    2016-02-24

    Cross-dehydrogenative-coupling (CDC) between C-H/C-H bonds of indoles and cyclic ethers/cycloalkanes is made viable through a simple transition-metal-free pathway. With the aid of only di-tert-butyl peroxide, a number of inactive cyclic ethers and cycloalkanes can be directly coupled with indole derivatives in satisfactory yields. PMID:26842403

  4. Metal ion complexation by ionizable crown ethers. Progress report, January 1, 1991--December 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Bartsch, R.A.

    1993-07-01

    Cyclic and acyclic polyether compounds with pendent carboxylic acid, phosphonic acid monoethyl ester, sulfonic acid, phosphinic acid and hydroxamic acid groups have been synthesized. The proton-ionizable polyethers can come with and without lipophilic groups. Two types of lipophilic di-ionizable lariat ethers have been prepared. Conformations of proton-ionizable lariat ethers have been probed. Competitive alkali metal cation transport by syn-(decyl)dibenzo-16-crown-5-oxyacetic acid and lipophilic proton-ionizable dibenzo lariat ethers in polymer-supported liquid membranes was studied. Complexation of alkali metal cations with ionized lariat ethers was studied. Condensation polymerization of cyclic and acyclic dibenzo polyethers containing pendent mono-ionizable groups with formaldehyde produces novel ion exchange resins with both ion exchange sites for metal ion complexation and polyether binding sites for metal ion recognition. Resins prepared from lariat ether dibenzo phosphonic acid monoethyl esters show strong sorption of divalent heavy metal cations with selectivity for Pb{sup 2+}.

  5. Zinc(II)-Chloride Induced Thioalkylation of Aluminium Enolates : Enantioselective Synthesis of Estradiol-3-Methyl-17-tert-Butyl Diether

    OpenAIRE

    Groth, Ulrich; Kohler, Thomas; Taapken, Thomas

    1991-01-01

    Zinc(II)-chloride induced thioalkylation of the aluminium enolate 6 generated by conlugate reduction of the enone 5 leads - directly or via its trimethylsilylenol ether 6 - to alkylated hydrindanones 10 which are important intermediates in the synthesis of 19-norsteroids such as the title compound estradiol-3-methyl-17-tert-butyl diether 12

  6. Kapok oil methyl esters

    International Nuclear Information System (INIS)

    The increased need for biodiesel feedstocks has caused various vegetable oils to be examined for this purpose. In the present work, the methyl esters of kapok (Ceiba pentandra) oil were prepared. The essential fuel properties were comprehensively determined and evaluated in comparison to specifications in biodiesel standards and some prior results. The kinematic viscosity of kapok oil methyl esters was greater than expected, an observation traced to the elevated amounts of methyl esters with cyclic moieties. Overall, kapok oil is a potential biodiesel feedstock. The 1H and 13C NMR spectra of kapok methyl esters are reported. - Highlights: • Methyl esters of kapok oil generally acceptable as a biodiesel fuel. • Kapok oil methyl esters a fuel with elevated content of fatty acid methyl esters containing cyclic moieties. • Kinematic viscosity of kapok oil methyl esters elevated likely due to fatty ester methyl esters with cyclic moieties. • Discusses and compares present results with prior literature

  7. 40 CFR 721.4040 - Glycols, polyethylene-, 3-sulfo-2-hydroxypropyl-p-(1,1,3,3-tetra-methylbutyl)phenyl ether, sodium...

    Science.gov (United States)

    2010-07-01

    ...-hydroxypropyl-p-(1,1,3,3-tetra-methylbutyl)phenyl ether, sodium salt. 721.4040 Section 721.4040 Protection of...-, 3-sulfo-2-hydroxypropyl-p-(1,1,3,3-tetra-methylbutyl)phenyl ether, sodium salt. (a) Chemical..., polyethylene-, 3-sulfo-2-hydroxypropyl-p-(1,1,3,3-tetramethyl butyl)phenyl ether, sodium salt (P-90-1565)...

  8. Customer exposure to MTBE, TAME, C6 alkyl methyl ethers, and benzene during gasoline refueling.

    OpenAIRE

    Vainiotalo, S; Peltonen, Y; Ruonakangas, A; Pfäffli, P

    1999-01-01

    We studied customer exposure during refueling by collecting air samples from customers' breathing zone. The measurements were carried out during 4 days in summer 1996 at two Finnish self-service gasoline stations with "stage I" vapor recovery systems. The 95-RON (research octane number) gasoline contained approximately 2.7% methyl tert-butyl ether (MTBE), approximately 8.5% tert-amyl methyl ether (TAME), approximately 3.2% C6 alkyl methyl ethers (C6 AMEs), and 0.75% benzene. The individual ex...

  9. Solvent effects on hydrogen bonding between primary alcohols and esters

    Institute of Scientific and Technical Information of China (English)

    DHARMALINGAM K.; RAMACHANDRAN K.; SIVAGURUNATHAN P.

    2006-01-01

    The interaction by hydrogen bond formation of some primary alcohols (1-heptanol, 1-octanol and 1-decanol) with esters (methyl methacrylate, ethyl methacrylate and butyl methacrylate) was investigated in non-polar solvents viz., n-heptane,CCh and benzene by means of FTIR spectroscopy. Formation constants and free energy changes of complex formation were determined. The dependence of the equilibrium constants and free energy changes of complex formation on the alkyl chain length of both the alcohols and esters are discussed. The solvent effect on the hydrogen bond formation is discussed in terms of specific interaction between the solute and solvent.

  10. 21 CFR 582.3173 - Butylated hydroxytoluene.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Butylated hydroxytoluene. 582.3173 Section 582.3173 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 582.3173 Butylated hydroxytoluene. (a) Product. Butylated hydroxytol- uene. (b) Tolerance....

  11. 21 CFR 182.3173 - Butylated hydroxytoluene.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Butylated hydroxytoluene. 182.3173 Section 182.3173 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD....3173 Butylated hydroxytoluene. (a) Product. Butylated hydroxytoluene. (b) Tolerance. This substance...

  12. Ether formulations of relativity

    Energy Technology Data Exchange (ETDEWEB)

    Duffy, M.C.

    1980-12-01

    Contemporary ether theories are surveyed and criticized, 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 criticized. Cosmological evidence suggesting an ether is mentioned. Only ether theories formally identical to Relativity have been published in depth. They stand criticized 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. 103 references.

  13. Ether formulations of relativity

    International Nuclear Information System (INIS)

    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)

  14. Free radical-derived quinone methide mediates skin tumor promotion by butylated hydroxytoluene hydroperoxide: expanded role for electrophiles in multistage carcinogenesis.

    OpenAIRE

    Guyton, K Z; Bhan, P; Kuppusamy, P.; Zweier, J L; Trush, M A; Kensler, T W

    1991-01-01

    Free radical derivatives of peroxides, hydroperoxides, and anthrones are thought to mediate tumor promotion by these compounds. Further, the promoting activity of phorbol esters is attributed, in part, to their ability to stimulate the cellular generation of oxygen radicals. A hydroperoxide metabolite of butylated hydroxytoluene, 2,6-di-tert-butyl-4-hydroperoxyl-4-methyl-2,5-cyclohexadienone (BHTOOH), has previously been shown to be a tumor promoter in mouse skin. BHTOOH is extensively metabo...

  15. Catalytic oxidation of dimethyl ether

    Energy Technology Data Exchange (ETDEWEB)

    Zelenay, Piotr; Wu, Gang; Johnston, Christina M.; Li, Qing

    2016-05-10

    A composition for oxidizing dimethyl ether includes an alloy supported on carbon, the alloy being of platinum, ruthenium, and palladium. A process for oxidizing dimethyl ether involves exposing dimethyl ether to a carbon-supported alloy of platinum, ruthenium, and palladium under conditions sufficient to electrochemically oxidize the dimethyl ether.

  16. Antioxidants Inhibit Formation of 3-Monochloropropane-1,2-diol Esters in Model Reactions.

    Science.gov (United States)

    Li, Chang; Jia, Hanbing; Shen, Mingyue; Wang, Yuting; Nie, Shaoping; Chen, Yi; Zhou, Yongqiang; Wang, Yuanxing; Xie, Mingyong

    2015-11-11

    The capacities of six antioxidants to inhibit the formation of 3-monochloropropane-1,2 diol (3-MCPD) esters were examined in this study. Inhibitory capacities of the antioxidants were investigated both in chemical models containing the precursors (tripalmitoyl glycerol, 1,2-dipalmitoyl-sn-glycerol, monopalmitoyl glycerol, and sodium chloride) of 3-MCPD esters and in oil models (rapeseed oil and sodium chloride). Six antioxidants, butylated hydroxytoluene (BHT), butylated hydroxy anisole (BHA), tert-butyl hydroquinone (TBHQ), propyl gallate (PG), L-ascorbyl palmitate (AP), and α-tocopherol (VE), were found to exhibit inhibiting capacities on 3-MCPD ester formation both in chemical models and in oil models. TBHQ provided the highest inhibitory capacity both in chemical models and in oil models; 44% of 3-MCPD ester formation was inhibited in the presence of TBHQ (66 mg/kg of oil) after heating of rapeseed oil at 230 °C for 30 min, followed by PG and AP. BHT, BHA, and VE appeared to have weaker inhibitory abilities in both models. VE exhibited the lowest inhibition rate; 22% of 3-MCPD esters were inhibited in the presence of VE (172 mg/kg of oil) after heating of rapeseed oil at 230 °C for 30 min. In addition, the inhibition rates of PG and VE decreased dramatically with an increase in temperature or heating time. The results suggested that some antioxidants, such as TBHQ, PG, and AP, could be the potential inhibitors of 3-MCPD esters in practice. PMID:26478126

  17. 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)

  18. Reaction Pathways and Energetics of Etheric C–O Bond Cleavage Catalyzed by Lanthanide Triflates

    Energy Technology Data Exchange (ETDEWEB)

    Assary, Rajeev S.; Atesin, Abdurrahman C.; Li, Zhi; Curtiss, Larry A.; Marks, Tobin J.

    2013-09-06

    Efficient and selective cleavage of etheric C-O bonds is crucial for converting biomass into platform chemicals and liquid transportation fuels. In this contribution, computational methods at the DFT B3LYP level of theory are employed to understand the efficacy of lanthanide triflate catalysts (Ln(OTf)3, Ln = La, Ce, Sm, Gd, Yb, and Lu) in cleaving etheric C-O bonds. In agreement with experiment, the calculations indicate that the reaction pathway for C-O cleavage occurs via a C-H → O-H proton transfer in concert with weakening of the C-O bond of the coordinated ether substrate to ultimately yield a coordinated alkenol. The activation energy for this process falls as the lanthanide ionic radius decreases, reflecting enhanced metal ion electrophilicity. Details of the reaction mechanism for Yb(OTf)3-catalyzed ring opening are explored in depth, and for 1-methyl-d3-butyl phenyl ether, the computed primary kinetic isotope effect of 2.4 is in excellent agreement with experiment (2.7), confirming that etheric ring-opening pathway involves proton transfer from the methyl group alpha to the etheric oxygen atom, which is activated by the electrophilic lanthanide ion. Calculations of the catalytic pathway using eight different ether substrates indicate that the more rapid cleavage of acyclic versus cyclic ethers is largely due to entropic effects, with the former C-O bond scission processes increasing the degrees of freedom/particles as the transition state is approached.

  19. Selective transport of Sr2+ from simulated nuclear waste solution by polymer inclusion membrane containing a crown ether carrier

    International Nuclear Information System (INIS)

    The extraction of Sr2+ from acidic nitrate solution with polymer inclusion membranes (PIMs) made from cellulose tri acetate (CTA), Di-tert-butyl-cyclohexano-18-crown-6 (DtBuCH18C6) and nitrophenyl n-octyl ether (NPOE) was studied. Transport rates were calculated at varying feed acidities. Selective transport of Sr2+ over other fission products was observed. (author)

  20. TOXICITY OF METHYL-TERT BYTYL ETHER (MTBE) TO PLANTS (AVENA SATIVA, ZEA MAYS, TRITICUM AESTIVUM, AND LACTUCA SATIVA)

    Science.gov (United States)

    Effects of Methyl tert-butyl ether (MTBE) on the germination of seeds and growth of the plant were studied in some laboratory experiments. Test plants were wild oat (Avena sative), sweet corn (Zea mays), wheat (Triticum aestivum), and lettuce (Lactuca sativa). Seed germination,...

  1. tert-Butyl N-[2-(N-isobutyl-4-meth-oxy-benzene-sulfonamido)-eth-yl]carbamate.

    Science.gov (United States)

    Bai, Xiao-Guang; Wang, Ju-Xian

    2014-06-01

    The title compound, C18H30N2O5S, was synthesized by the reaction of tert-butyl 2-(iso-butyl-amino)-ethyl-carbamate with p-meth-oxy-phenyl-sulfonyl chloride. In the mol-ecule, two intra-molecular C-H⋯O hydrogen bonds are observed. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds involving the imino group N atom and the ester group O atom into chains running parallel to the b axis. The chains are further connected by C-H⋯O hydrogen bonds, forming layers parallel to the bc plane. PMID:24940254

  2. Tandem Bond-Forming Reactions of 1-Alkynyl Ethers.

    Science.gov (United States)

    Minehan, Thomas G

    2016-06-21

    Electron-rich alkynes, such as ynamines, ynamides, and ynol ethers, are functional groups that possess significant potential in organic chemistry for the formation of carbon-carbon bonds. While the synthetic utility of ynamides has recently been expanded considerably, 1-alkynyl ethers, which possess many of the reactivity features of ynamides, have traditionally been far less investigated because of concerns about their stability. Like ynamides, ynol ethers are relatively unhindered to approach by functional groups present in the same or different molecules because of their linear geometry, and they can potentially form up to four new bonds in a single transformation. Ynol ethers also possess unique reactivity features that make them complementary to ynamides. Research over the past decade has shown that ynol ethers formed in situ from stable precursors engage in a variety of useful carbon-carbon bond-forming processes. Upon formation at -78 °C, allyl alkynyl ethers undergo a rapid [3,3]-sigmatropic rearrangement to form allyl ketene intermediates, which may be trapped with alcohol or amine nucleophiles to form γ,δ-unsaturated carboxylic acid derivatives. The process is stereospecific, takes place in minutes at cryogenic temperatures, and affords products containing (quaternary) stereogenic carbon atoms. Trapping of the intermediate allyl ketene with carbonyl compounds, epoxides, or oxetanes instead leads to complex α-functionalized β-, γ-, or δ-lactones, respectively. [3,3]-Sigmatropic rearrangement of benzyl alkynyl ethers also takes place at temperatures ranging from -78 to 60 °C to afford substituted 2-indanones via intramolecular carbocyclization of the ketene intermediate. tert-Butyl alkynyl ethers containing pendant di- and trisubstituted alkenes and enol ethers are stable to chromatographic isolation and undergo a retro-ene/[2 + 2] cycloaddition reaction upon mild thermolysis (90 °C) to afford cis-fused cyclobutanones and donor

  3. The compound ethers of glycerin

    International Nuclear Information System (INIS)

    In this chapter of book authors describe several methods of receiving of compound ethers of glycerin. The important technic significance have compound glycerin ether and nitric acid. This compound receive by reaction of glycerin with fuming nitric acid

  4. Synthesis and properties of segmented copolymers of polyphenylene ether and tetra-amide units

    NARCIS (Netherlands)

    Krijgsman, Josien; Feijen, Jan; Gaymans, Reinoud J.

    2003-01-01

    Copolymers of telechelic poly(2,6-dimethyl-1,4-phenylene ether) segments with terephthalic methyl ester endgroups (PPE-2T, 3100 g/mol), uniform crystallizable tetra-amide units based on nylon-6,T (T6T6T, 13 wt%) and dodecanediol (C12) as an extender were made via a polycondensation reaction. The PPE

  5. Studies of esters and their isotopomers using the molecular beam fourier transform microwave (MB-FTMW) spectroscopy

    OpenAIRE

    Sutikdja, Lilian Wijaya

    2014-01-01

    A fundamental nomenclature for the aliphatic compounds especially the saturated hydrocarbons has been defined and applied to all esters reported in this dissertation. It can be shown that with the redefined nomenclature each conformer can be easily identified by name and since the conformational information is included in the notation it is also effective to indicate directly the geometry of the respective conformer. Totally four acetic acid esters (isoamyl acetate, n-propyl acetate, n-butyl ...

  6. Propenyl ether monomers for photopolymerization

    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.

  7. The micromethod for determination of cholesterol, cholesteryl esters and phospholipids

    Directory of Open Access Journals (Sweden)

    Okabe,Akinobu

    1974-12-01

    Full Text Available We examined the method for determining microquantities of lipids, including cholesterol, cholesteryl esters and phospholipids. A standard colorimetric procedure of cholesteryl esters was modified to accommodate a quantitative thin-layer chromatography. This method involved the following steps. (1 Separation of lipids by a thin-layer chromatography: Lipids were applied to Silica gel G plates. Plates were developed with petroleum ether-diethyl etheracetic acid (82: 18: 2, vIvIv. (2 Elution of cholesterol and its esters from scraped silica gel: After scraping the silica gel with adhered cholesterol and its esters, they were eluted with chloroform-methanol (4: 1, v,tv. In the case of phspholipids, the silica gel was calcified. (3 Colorimetric determination of the lipids: Cholesterol and its esters eluted from the silica gel were determined by the method of ZAK with ROSENTHAL'S color reagent directly and after saponification, respectively. Phospholipids were calculated from the phosphorous content determined by the method of KATES. On the basis of examination of recovery and analyses of lipids extracted from tissue, it was concluded that this method permitted a reliable estimation of microquantities of cholesterol, its esters and phospholipids from small amounts of biological materials.

  8. Biosynthesis of archaeal membrane ether lipids.

    Science.gov (United States)

    Jain, Samta; Caforio, Antonella; Driessen, Arnold J M

    2014-01-01

    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 LUCA. It examines recent advances made in the field of pathway reconstruction in bacteria. PMID:25505460

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

    Science.gov (United States)

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

    2016-02-01

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

  10. Analysis of alcohols, as dimethylglycine esters, by electrospray ionization tandem mass spectrometry.

    Science.gov (United States)

    Johnson, D W

    2001-03-01

    Dimethylglycine (DMG) esters are new derivatives for the rapid, sensitive and selective analysis of primary and secondary alcohols, in complex mixtures, by electrospray ionization tandem mass spectrometry (ESI-MS/MS). Their development was inspired by the use of the complementary dimethylaminoethyl esters for the trace, rapid analysis of fatty acids. DMG esters are simply prepared by heating a dichloromethane solution of the imidazolide of dimethylglycine, containing triethylamine, and an alcohol. DMG esters of long-chain fatty alcohols, isoprenoidal alcohols and hydroxy-acids are analysed by electrospray ionization tandem mass spectrometry with a precursor ion of m/z 104 scan. Diols, glyceryl esters, glyceryl ethers and some sterols are analysed by a neutral loss of 103 Da scan. Trimethylglycine (TMG) ester iodides, prepared by alkylation of DMG esters with methyl iodide, are more sensitive derivatives for molecules containing secondary alcohol groups, such as cholesterol and gibberellic acid. They are analysed by a precursor ion of m/z 118 scan. DMG or TMG derivatives were shown to be at least comparable and sometimes an order of magnitude more sensitive than N-methylpyridyl ether derivatives for ESI-MS/MS analysis of the different classes of alcohols. Applications of these derivatives for the diagnosis of inherited disorders and the analysis of natural products are presented. PMID:11312519

  11. Comparative examination of radiation polymerization in a thin layer of acrylic and methacrylic esters

    International Nuclear Information System (INIS)

    Some features of radiation polymerization of acrylic esters CH2 double-bond CH-COOR (AE) and their methacrylic analogs CH2 double-bond C(CH3)-COOR (ME) in a thin layer have not been explained within the framework of concepts of the radical mechanism of radiation polymerization. To determine the causes of the anomalies, the authors comparatively studied polymerization of a series of AE and ME in a thin layer under the effect of accelerated electrons, butyl acrylate and butyl methacrylate, ethylene glycol diacrylate and ethylene glycol dimethacrylate and diethylene glycol diacrylate and diethylene glycol dimethacrylate

  12. Dehydrogenative Cross-Coupling Reaction between N-Aryl α-Amino Acid Esters and Phenols or Phenol Derivative for Synthesis of α-Aryl α-Amino Acid Esters.

    Science.gov (United States)

    Salman, Muhammad; Zhu, Zhi-Qiang; Huang, Zhi-Zhen

    2016-04-01

    A novel dehydrogenative cross-coupling (DCC) reaction between N-arylglycine esters and phenols or 1,3,5-trimethoxybenzene was developed by copper catalysis using di-tert-butyl peroxide (DTBP) as an oxidant. Under optimized conditions, a range of N-arylglycine esters 1 underwent the DCC reaction smoothly with various phenols 2 or 1,3,5-trimethoxybenzene 4 to give desired α-aryl α -amino acid esters 3 or 5, respectively, with high ortho regioselectivities in a moderate to excellent yield. A possible mechanism involving aromatic electrophilic substitution is proposed. PMID:26984111

  13. Bacterial degradation of glycol ethers.

    Science.gov (United States)

    Kawai, F

    1995-12-01

    Assimilation of ethyleneglycol (EG) ethers by polyethyleneglycol-utilizing bacteria was examined. Ethyleneglycol ether-utilizing bacteria were also isolated from soil and activated sludge samples by enrichment-culture techniques. Three strains (4-5-3, EC 1-2-1 and MC 2-2-1) were selected and characterized as Pseudomonas sp. 4-5-3, Xanthobacter autotrophicus, and an unidentified gram-negative, non-spore-forming rod respectively. Their growth characteristics were examined: Pseudomonas sp. 4-5-3 assimilated EG (diethyleneglycol, DEG) monomethyl, monoethyl and monobutyl ethers, DEG, propanol and butanol. X. autotrophicus EC 1-2-1 grew well on EG monoethyl and monobutyl ethers, EG and primary alcohols (C1-C4), and slightly on EG monomethyl ether. The strain MC 2-2-1 grew on EG monomethyl ether, EG, primary alcohols (C1-C4), and 1,2-propyleneglycol (PG). The mixed culture of Pseudomonas sp. 4-5-3 and X. autotrophicus EC 1-2-1 showed better growth and improved degradation than respective single cultures towards EG monomethyl, monoethyl or monobutyl ethers. Intact cells of Pseudomonas sp. 4-5-3 degraded various kinds of monoalkyl ethers, which cannot be assimilated by the strain. Metabolic products were characterized from reaction supernatants of intact cells of Pseudomonas sp. 4-5-3 with EG or DEG monoethyl ethers: they were analyzed by thin-layer chromatography and GC-MS and found to be ethoxyacetic acid and ethoxyglycoxyacetic acid. Also, PG monoalkyl ethers (C1-C4), dipropyleneglycol monoethyl and monomethyl ethers and tripropyleneglycol monomethyl ether were assimilated by polypropyleneglycol-utilizing Corynebacterium sp. 7. PMID:8597556

  14. Biodegradation of Di-n-Butyl Phthalate by a Newly Isolated Halotolerant Sphingobium sp.

    OpenAIRE

    Decai Jin; Xiao Kong; Bingjian Cui; Zhihui Bai; Hongxun Zhang

    2013-01-01

    A Gram-negative strain (TJ) capable of growing aerobically on mixed phthalate esters (PAEs) as the sole carbon and energy source was isolated from the Haihe estuary, Tianjin, China. It was identified as belonging to the Sphingobium genus on the basis of morphological and physiological characteristics and 16S rRNA and gyrb gene sequencing. The batch tests for biodegradation of di-n-butyl phthalate (DBP) by the Sphingobium sp. TJ showed that the optimum conditions were 30 °C, pH 7.0, and the ab...

  15. Oxidative DNA damage in male wistar rats exposed to di-n-butyl phthalate

    DEFF Research Database (Denmark)

    Wellejus, A.; Dalgaard, Majken; Loft, S.

    2002-01-01

    Dialkyl phthalate esters are used in the plastic industry and widely distributed in the environment, Previously, it has been shown that di-n-butyl phthalate (DBP) produces testicular atrophy and liver enlargement in rodents, and the mechanisms behind this could involve reactive oxygen species (ROS...... involved in the formation of testicular atrophy in phthalate-exposed rats, no apparent sign of oxidative DNA damage was found after phthalate exposure perinatally or during the preadult stage, With respect to phthalate-induced oxidative DNA damage in the liver, it appears that the developmental stage...

  16. Effects of di-n-butyl phthalate on the physiology and ultrastructure of cucumber seedling roots

    OpenAIRE

    Ying ZHANG; Tao, Yue; Sun, Guoqiang; Wang, Lei

    2014-01-01

    Agricultural pollution caused by the use of plastic sheetings has been documented to be a widespread problem in most of the major crop-planting regions of the world. In order to better understand the phytotoxic mechanisms induced by phthalic acid esters involved with this problem, Cucumber sativus L. cv Jinyan No. 4 were sown in pots to the three-leaf-stage in the presence of di-n-butyl phthalate (DBP; 0, 30, 50, 100, and 200 mg L−1) for 1, 3, 5, or 7 days. Physiology, biochemistry, and ultra...

  17. tert-Butyl N-[2-(N-isobutyl-4-methoxybenzenesulfonamidoethyl]carbamate

    Directory of Open Access Journals (Sweden)

    Xiao-Guang Bai

    2014-06-01

    Full Text Available The title compound, C18H30N2O5S, was synthesized by the reaction of tert-butyl 2-(isobutylaminoethylcarbamate with p-methoxyphenylsulfonyl chloride. In the molecule, two intramolecular C—H...O hydrogen bonds are observed. In the crystal, molecules are linked by N—H...O hydrogen bonds involving the imino group N atom and the ester group O atom into chains running parallel to the b axis. The chains are further connected by C—H...O hydrogen bonds, forming layers parallel to the bc plane.

  18. An electron spin resonance investigation of ester cation radicals at low temperatures

    International Nuclear Information System (INIS)

    The cation radicals of a series of esters have been produced by γ-irradiation of CFCl3 matrices containing the ester at 77 K. In previous work cations of methyl and ethyl esters were investigated. In this work we report results for larger esters. The cations of these esters are found to undergo immediate internal proton-transfer reactions involving specific sites on one of the alkyl substituents. For example, deuteration studies show that proton transfer occurs from the terminal methyl group in propyl formate to produce -OCH2CH2CH2; whereas in propyl acetate -OCH2CHCH3 is produced. The proton lost from these groups is assumed to add to an oxygen on the ester functional group. In the case of propyl acetate and esters with branched side chains we find that fragmentation reactions follow the proton transfer. In the cases of t-butyl acetate and isobutyl formate the fragmentation process occurs at 77 K and results in the isobutylene cation. Neopentyl formate gives evidence for the cation radical, an RCH2 radical and the fragmentation radical cation as the sample is annealed. These results show that ester cation radicals are highly reactive even at low temperatures where proton-transfer and fragmentation reactions are found. (author)

  19. Structural insights from boron tribromide ether cleavage into lignites and low maturity coals from the New Zealand Coal Band

    DEFF Research Database (Denmark)

    Glombitza, Clemens; Mangelsdorf, Kai; Horsfield, Brian

    2011-01-01

    Ether functionalities form an important cross-linking structure within the macromolecular organic matrix of lignites and coals. To obtain a deeper insight into the complex internal structure of such macromolecules and the maturation related changes of the ether compounds within the network...... structure, boron tribromide (BBr3) ether cleavage was applied to a series of lignite and coal samples of different maturity (R0 0.27–0.80%) obtained from coal mines and natural outcrops from the North and South Island of New Zealand. Terminal ether-bound alcohols rapidly decrease during diagenesis and occur...... important cross-linking substructures within the macromolecular matrix of lignites and coals being sterically protected within the macromolecular network during the maturation process. Additional cross-linking substructures were (poly)ether aromatics, esters and ketones...

  20. Transdermal uptake of diethyl phthalate and di(n-butyl) phthalate directly from air: Experimental verification

    DEFF Research Database (Denmark)

    Weschler, Charles J.; Bekö, Gabriel; Koch, Holger M.; Salthammer, Tunga; Schripp, Tobias; Toftum, Jørn; Clausen, Geo

    2015-01-01

    Background: Fundamental considerations indicate that, for certain phthalate esters, dermal absorption from air is an uptake pathway that is comparable to or greater than inhalation. Yet this pathway has not been experimentally evaluated and has been largely overlooked when assessing uptake of...... phthalate esters. Objectives: This study investigated transdermal uptake, directly from air, of diethyl phthalate (DEP) and di(n-butyl) phthalate (DnBP) in humans. Methods: In a series of experiments, six human participants were exposed for 6 hr in a chamber containing deliberately elevated air...... concentrations of DEP and DnBP. The participants either wore a hood and breathed air with phthalate concentrations substantially below those in the chamber or did not wear a hood and breathed chamber air. All urinations were collected from initiation of exposure until 54 hr later. Metabolites of DEP and Dn...

  1. Ether and Relativity

    CERN Document Server

    Farhoudi, Mehrdad

    2015-01-01

    We consider one of the fundamental debates in performing the relativity theory, namely, the ether and the relativity points of view, in a way to aid the learning of the subjects. In addition, we present our views and prospects while describing the issues that being accessible to many physicists and allowing broader views. Also, we very briefly review the two almost recent observations of the Webb redshift and the ultra high-energy cosmic rays, and the modified relativity models that have been presented to justify them, wherein we express that these justifications have not been performed via a single model with a single mechanism.

  2. Ether and Relativity

    Science.gov (United States)

    Farhoudi, Mehrdad; Yousefian, Maysam

    2016-05-01

    We consider one of the fundamental debates in performing the relativity theory, namely, the ether and the relativity points of view, in a way to aid the learning of the subjects. In addition, we present our views and prospects while describing the issues that being accessible to many physicists and allowing broader views. Also, we very briefly review the two almost recent observations of the Webb redshift and the ultra high energy cosmic rays, and the modified relativity models that have been presented to justify them, wherein we express that these justifications have not been performed via a single model with a single mechanism.

  3. Forensic analysis of tertiary-butyl alcohol (TBA) detections in a hydrocarbon-rich groundwater basin.

    Science.gov (United States)

    Quast, Konrad W; Levine, Audrey D; Kester, Janet E; Fordham, Carolyn L

    2016-04-01

    Tertiary-butyl alcohol (TBA), a high-production volume (HPV) chemical, was sporadically detected in groundwater and coalbed methane (CBM) wells in southeastern Colorado's hydrocarbon-rich Raton Basin. TBA concentrations in shallow water wells averaged 75.1 μg/L, while detections in deeper CBM wells averaged 14.4 μg/L. The detection of TBA prompted a forensic investigation to try to identify potential sources. Historic and recent data were reviewed to determine if there was a discernable pattern of TBA occurrence. Supplemental samples from domestic water wells, monitor wells, CBM wells, surface waters, and hydraulic fracturing (HF) fluids were analyzed for TBA in conjunction with methyl tertiary-butyl ether (MTBE) and ethyl tertiary-butyl ether (ETBE), proxies for evidence of contamination from reformulated gasoline or associated oxygenates. Exploratory microbiological sampling was conducted to determine if methanotrophic organisms co-occurred with TBA in individual wells. Meaningful comparisons of historic TBA data were limited due to widely varying reporting limits. Mapping of TBA occurrence did not reveal any spatial patterns or physical associations with CBM operations or contamination plumes. Additionally, TBA was not detected in HF fluids or surface water samples. Given the widespread use of TBA in industrial and consumer products, including water well completion materials, it is likely that multiple diffuse sources exist. Exploratory data on stable isotopes, dissolved gases, and microbial profiling provide preliminary evidence that methanotrophic activity may be producing TBA from naturally occurring isobutane. Reported TBA concentrations were significantly below a conservative risk-based drinking water screening level of 8000 μg/L derived from animal toxicity data. PMID:26946495

  4. 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

    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......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...

  5. Demand boom boosts ethyl, butyl acetate

    International Nuclear Information System (INIS)

    US ethyl and butyl acetate markets are being described as 'extremely tight.' One major domestic producer is 'in a sold-out position' and has 'gone on sales control' with respect to these two products. Producers say that sales of both ethyl and butyl acetate have increased during the past year, and industry observers say they expect to see an April 1 price initiative of 2 cts to 3 cts/lb, and possibly a second increase in October. While one producer suggests that this market strength could be 'a sign that the coatings industry is turning around,' most agree that reformulation is the principal driver of growth. Ethyl acetate is said to be replacing methyl ethyl ketone in many formulations, while butyl acetate and butyl acetate blends are substituting for methyl isobutyl ketone. In addition, both ethyl and butyl acetate work as substitutes for xylene and toluene in certain applications. In an effort to conform to the requirements of the Clean Air Act of 1990 and to cooperate with the Environmental Protection Agency's 33/50 voluntary emissions reduction program, coatings manufacturers are moving as quickly as possible to eliminate solvents from their products. And although solvents as a whole will eventually see a dramatic decline in consumption, the temporary beneficiaries of reformulation will be certain of the oxygenated solvents, says Jeff Back, business manager at Kline ampersand Co

  6. Maleik Anhidrit Stiren Kopolimerinin Ester ve Karboksilat Tuz Türevlerinin Sentezi ve Karakterizasyonu

    OpenAIRE

    Koçyiğit, Ümit Muhammet; Zengin, Hacı Bayram

    2014-01-01

    In this study, to increase thermal stability of maleic anhydride styrene copolymers; monoesters and carboxylate salt derivatives of maleic anhydride styrene were obtained by reaction of maleic anhydride styrene copolymer with n-propyl alcohol, n-butyl alcohol and ammonia. Fourier transform infrared spectroscopy (FTIR) was used for characterization and Thermogravimetric Analysis (TGA) was used for thermal analysis. As an result of this study, when TGA curves were analyzed, though ester derivat...

  7. Syntheses of Macrocyclic Amides from L-Amino Acid Esters by RCM

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A series of succinate-derived macrocyclic amides( 1 ) was synthesized via ring-closing metathesis (RCM) as the key step. The substrate included 12 to 15 members. The metathesis precursors were obtained from the amide coupling of tert-butyl 3-carboxyhex-5-enoate(2) with numerous side-chain alkenylated amino acid esters of general type(3)derived from L-lysine and L-ornithine.

  8. Apomorphine and its esters

    DEFF Research Database (Denmark)

    Borkar, Nrupa; Chen, Zhizhong; Saaby, Lasse;

    2016-01-01

    Oral delivery of apomorphine via prodrug principle may be a potential treatment for Parkinson's disease. The purpose of this study was to investigate the transport and stability of apomorphine and its esters across Caco-2 cell monolayer and their affinity towards chylomicrons. Apomorphine...

  9. Lubricants based on synthetic esters; Schmierstoffe auf Basis synthetischer Ester

    Energy Technology Data Exchange (ETDEWEB)

    Fahl, J. [Forschung und Entwicklung Kaeltemaschinenoele, Fuchs DEA Schmierstoffe GmbH, Hamburg (Germany)

    2000-07-01

    This article describes the synthetic esters that are being used in refrigeration applications that use chlorine-free working fluids. The chemical basics involved in these high-performance lubricants, their manufacture and their lubricating properties are looked at in detail. The history of their development from their use as machining oils, lubricants for weapons and two-stroke engines through to turbine lubricants and as hydraulic oil in aeronautics is reviewed. Modern neopentyl-polyol esters used in refrigeration applications are described. Further, the chemical structures and applications of complex esters, carbonate esters, aromatic and silicate esters are looked at.

  10. Uptake and Metabolism of Phthalate Esters by Edible Plants.

    Science.gov (United States)

    Sun, Jianqiang; Wu, Xiaoqin; Gan, Jay

    2015-07-21

    Phthalate esters (PAEs) are large-volume chemicals and are found ubiquitously in soil as a result of widespread plasticulture and waste disposal. Food plants such as vegetables may take up and accumulate PAEs from soil, potentially imposing human health risks through dietary intake. In this study, we carried out a cultivation study using lettuce, strawberry, and carrot plants to determine the potential of plant uptake, translocation, and metabolism of di-n-butyl phthalate (DnBP) and di(2-ethylhexyl) phthalate (DEHP) and their primary metabolites mono-n-butyl phthalate (MnBP) and mono(2-ethylhexyl) phthalate (MEHP). All four compounds were detected in the plant tissues, with the bioconcentration factors (BCFs) ranging from 0.16 ± 0.01 to 4.78 ± 0.59. However, the test compounds were poorly translocated from roots to leaves, with a translocation factor below 1. Further, PAEs were readily transformed to their monoesters following uptake. Incubation of PAEs and monoalkyl phthalate esters (MPEs) in carrot cell culture showed that DnBP was hydrolyzed more rapidly than DEHP, while the monoesters were transformed more quickly than their parent precursors. Given the extensive metabolism of PAEs to monoesters in both whole plants and plant cells, metabolism intermediates such as MPEs should be considered when assessing human exposure via dietary intake of food produced from PAE-contaminated soils. PMID:26090545

  11. Microreactors-A Powerful Tool to Synthesize Peroxycarboxylic Esters.

    Science.gov (United States)

    Illg, Tobias; Knorr, Annett; Fritzsche, Lutz

    2015-01-01

    The synthesis of peroxycarboxylic esters, as one subgroup of organic peroxides, is characterized by a high thermal hazard potential regarding process safety. In case of failure in the production process, e.g., if the heat of reaction cannot be removed sufficiently fast, decomposition reactions can be triggered, and as a result, remarkable amounts of heat and gas can be released and can cause a high extent of damage. Multifarious technical and organizational measures are necessary to ensure the safe industrial production of peroxides. With the introduction of microreaction technology plenty of possibilities have been opened to carry out highly exothermic reactions in smaller volumes and with more efficient heat removal. In this paper we report the application of three different microstructured reactors, representing different mixing strategies, to synthesize two peroxymonocarboxylic esters, namely tert-butyl peroxypivalate and tert-butyl peroxy-2-ethylhexanoate. The following reactor types were considered: an orifice microreactor, a split and recombine microreactor and a capillary tube reactor in combination with ultrasonication. The efficiency of the two phase liquid/liquid reaction is expressed in comparison of conversion and selectivity. With microreaction technology a remarkable increase in space-time-yield, ranging from 12,500 kg·m(-3)·h(-1) to 414,000 kg·m(-3)·h(-1), is achieved. PMID:26703553

  12. Microreactors—A Powerful Tool to Synthesize Peroxycarboxylic Esters

    Directory of Open Access Journals (Sweden)

    Tobias Illg

    2015-12-01

    Full Text Available The synthesis of peroxycarboxylic esters, as one subgroup of organic peroxides, is characterized by a high thermal hazard potential regarding process safety. In case of failure in the production process, e.g., if the heat of reaction cannot be removed sufficiently fast, decomposition reactions can be triggered, and as a result, remarkable amounts of heat and gas can be released and can cause a high extent of damage. Multifarious technical and organizational measures are necessary to ensure the safe industrial production of peroxides. With the introduction of microreaction technology plenty of possibilities have been opened to carry out highly exothermic reactions in smaller volumes and with more efficient heat removal. In this paper we report the application of three different microstructured reactors, representing different mixing strategies, to synthesize two peroxymonocarboxylic esters, namely tert-butyl peroxypivalate and tert-butyl peroxy-2-ethylhexanoate. The following reactor types were considered: an orifice microreactor, a split and recombine microreactor and a capillary tube reactor in combination with ultrasonication. The efficiency of the two phase liquid/liquid reaction is expressed in comparison of conversion and selectivity. With microreaction technology a remarkable increase in space-time-yield, ranging from 12,500 kg·m−3·h−1 to 414,000 kg·m−3·h−1, is achieved.

  13. Direct Dimethyl Ether Synthesis

    Institute of Scientific and Technical Information of China (English)

    Takashi Ogawa; Norio Inoue; Tutomu Shikada; Yotaro Ohno

    2003-01-01

    Dimethyl ether (DME) is a clean and economical alternative fuel which can be produced from natural gas through synthesis gas. The properties of DME are very similar to those of LP gas. DME can be used for various fields as a fuel such as power generation, transportation, home heating and cooking,etc. It contains no sulfur or nitrogen. It is not corrosive to any metal and not harmful to human body. An innovative process of direct synthesis of DME from synthesis gas has been developed. Newly developed catalyst in a slurry phase reactor gave a high conversion and high selectivity of DME production. One and half year pilot scale plant (5 tons per day) testing, which was supported by METI, had successfully finished with about 400 tons DME production.

  14. Gasoline ether oxygenate occurrence in Europe, and a review of their fate and transport characteristics in the environment

    Energy Technology Data Exchange (ETDEWEB)

    Stupp, D.; Gass, M.; Leiteritz, H. [Dr. Stupp Consulting DSC, Tauw, Bergisch Gladbach (Germany); Pijls, C. [TAUW, Apeldoorn (Netherlands); Thornton, S. [University of Sheffield, Sheffield (United Kingdom); Smith, J.; Dunk, M.; Grosjean, T.; Den Haan, K. [CONCAWE, Brussels (Belgium)

    2012-06-15

    Ether oxygenates are added to certain gasoline (petrol) formulations to improve combustion efficiency and to increase the octane rating. In this report the term gasoline ether oxygenates (GEO) refers collectively to methyl tertiary butyl ether (MTBE), ethyl tertiary butyl ether (ETBE), tertiary amyl methyl ether (TAME), diisopropyl ether (DIPE), tertiary amyl ethyl ether (TAEE), tertiary hexyl methyl ether (THxME), and tertiary hexyl ethyl ether (THxEE), as well as the associated tertiary butyl alcohol (TBA). This report presents newly collated data on the production capacities and use of MTBE, ETBE, TAME, DIPE and TBA in 30 countries (27 EU countries and Croatia, Norway and Switzerland) to inform continued and effective environmental management practices for GEO by CONCAWE members. The report comprises data on gasoline use in Europe that were provided by CONCAWE and obtained from the European Commission. Furthermore Societe Generale de Surveillance (SGS) provided detailed analytical data (more than 1,200 sampling campaigns) on the GEO composition of gasoline in European countries in the period 2000-2010. Another major aspect of this report is the investigation of GEO distribution in groundwater, drinking water, surface water, runoff water, precipitation (rain/snow) and air in the European environment. Apart from the general sources of literature for the study, local environmental authorities and institutes in the 30 European countries have been contacted for additional information. Finally, a review of the international literature on GEO natural attenuation processes was undertaken with a focus on international reports and peer-reviewed scientific publications to give an overview on the known fate, transport and degradation mechanisms of GEO in the subsurface, to inform risk-management strategies that may rely on natural attenuation processes. The literature reveals that all GEO compounds used in fuels are highly water soluble and weakly retarded by aquifer

  15. Compound list: butylated hydroxyanisole [Open TG-GATEs

    Lifescience Database Archive (English)

    Full Text Available butylated hydroxyanisole BHA 00156 ftp://ftp.biosciencedbc.jp/archive/open-tggates/...LATEST/Human/in_vitro/butylated_hydroxyanisole.Human.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/o...pen-tggates/LATEST/Rat/in_vivo/Liver/Single/butylated_hydroxyanisole.Rat.in_vivo.Liver.Single.zip ftp://ftp....biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Liver/Repeat/butylated_hydroxyanisole.Rat.in_vivo.Liver.Repeat.zip ...

  16. Rhodium(III)-Catalyzed C-H Activation/Annulation with Vinyl Esters as an Acetylene Equivalent

    OpenAIRE

    Webb, NJ; Marsden, SP; Raw, SA

    2014-01-01

    The behavior of electron-rich alkenes in rhodium-catalyzed C–H activation/annulation reactions is investigated. Vinyl acetate emerges as a convenient acetylene equivalent, facilitating the synthesis of sixteen 3,4-unsubstituted isoquinolones, as well as select heteroaryl-fused pyridones. The complementary regiochemical preferences of enol ethers versus enol esters/enamides is discussed

  17. Valyl benzyl ester chloride

    Directory of Open Access Journals (Sweden)

    Grzegorz Dutkiewicz

    2010-02-01

    Full Text Available In the title compound (systematic name: 1-benzyloxy-3-methyl-1-oxobutan-2-aminium chloride, C12H18NO2+·Cl−, the ester group is approximately planar, with a maximum deviation of 0.040 (2 Å from the least-squares plane, and makes a dihedral angle of 28.92 (16° with the phenyl ring. The crystal structure is organized by N—H...Cl hydrogen bonds which join the two components into a chain along the b axis. Pairs of chains arranged antiparallel are interconnected by further N—H...Cl hydrogen bonds, forming eight-membered rings. Similar packing modes have been observed in a number of amino acid ester halides with a short unit-cell parameter of ca 5.5 Å along the direction in which the chains run.

  18. 40 CFR 180.232 - Butylate; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Butylate; tolerances for residues. 180... PROGRAMS TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Specific Tolerances § 180.232 Butylate; tolerances for residues. (a) General. Tolerances are established for the herbicide butylate in...

  19. Intake of butylated hydroxyanisole and butylated hydroxytoluene and stomach cancer risk : results from analyses in the Netherlands : cohort study

    NARCIS (Netherlands)

    Botterweck, A.A.M.; Verhagen, H.; Goldbohm, R.A.; Kleinjans, J.; Brandt, P.A. van den

    2000-01-01

    Both carcinogenic and anticarcinogenic properties have been reported for the synthetic antioxidants butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). The association between dietary intake of BHA and BHT and stomach cancer risk was investigated in the Netherlands Cohort Study (NLCS)

  20. 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.

  1. 21 CFR 182.3169 - Butylated hydroxyanisole.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Butylated hydroxyanisole. 182.3169 Section 182.3169 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... generally recognized as safe for use in food when the total content of antioxidants is not over 0.02...

  2. 21 CFR 582.3169 - Butylated hydroxyanisole.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Butylated hydroxyanisole. 582.3169 Section 582.3169 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... substance is generally recognized as safe for use in food when the total content of antioxidants is not...

  3. Thermal Polymerization of N-Butyl Acrylate

    Science.gov (United States)

    Ingham, J. D.

    1982-01-01

    Simple new polymerization method enables production of n-butyl acrylate polymer of desired high molecular weight, without disadvantages that usually attend more conventional methods. Process, which is hybrid of thermal, solution, and emulsion polymerization methods, involves controlled thermal polymerization of monomer at moderate temperatures without use of catalysts or additives.

  4. CT colonography with and without butyl scopolamine

    International Nuclear Information System (INIS)

    The purpose of this study was to compare colorectal distention with and without butyl scopolamine (Buscopan) during CT colonography. A sixty-four-detector row CT colonography was performed without the administration of butyl scopolamine in 75 subjects (group without buscopan). These subjects were compared to 75 subjects who were premedicated with 20 mg of butyl scopolamine (group with buscopan). The large intestine was divided into six segments, and three observers recorded the degrees of colorectal distention using a 4-point scale for both dual positions (1=completely collapsed, 2=partially collapsed, 3=adequately but not optimally distended, 4=optimally distended). A total of 1,800 segments were evaluated. The average colorectal distention scores for the group without and with buscopan were 3.59 and 3.57, respectively. There was no significant difference between the two groups in terms of colorectal distention (p=0.48). Butyl scopolamine administration before CT colonography does not improve the overall adequacy of colorectal distention and our results do not support its routine use for CT colonography for screening purposes. (author)

  5. TRANSPORT OF METHYL TERT-BUTYL ETHER THROUGH ALFALFA PLANTS. (R825549C062)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  6. Modeling Of A Reactive Distillation Column: Methyl Tertiary Butyl Ether (Mtbe Simulation Studies

    Directory of Open Access Journals (Sweden)

    Ismail Mohd Saaid Abdul Rahman Mohamed and Subhash Bhatia

    2012-10-01

    Full Text Available A process simulation stage-wise reactive distillation column model formulated from equilibrium stage theory was developed. The algorithm for solving mathematical model represented by sets of differential-algebraic equations was based on relaxation method. Numerical integration scheme based on backward differentiation formula was selected for solving the stiffness of differential-algebraic equations. Simulations were performed on a personal computer (PC Pentium processor through a developed computer program using FORTRAN90 programming language. The proposed model was validated by comparing the simulated results with the published simulation results and with the pilot plant data from the literature. The model was capable of predicting high isobutene conversion for heterogeneous system, as desirable in industrial MTBE production process. The comparisons on temperature profiles, liquid composition profile and operating conditions of reactive distillation column also showed promising results. Therefore the proposed model can be used as a tool for the development and simulation of reactive distillation column.Keywords: Modeling, simulation, reactive distillation, relaxation method, equilibrium stage, heterogeneous, MTBE

  7. Modeling Of A Reactive Distillation Column: Methyl Tertiary Butyl Ether (Mtbe) Simulation Studies

    OpenAIRE

    2012-01-01

    A process simulation stage-wise reactive distillation column model formulated from equilibrium stage theory was developed. The algorithm for solving mathematical model represented by sets of differential-algebraic equations was based on relaxation method. Numerical integration scheme based on backward differentiation formula was selected for solving the stiffness of differential-algebraic equations. Simulations were performed on a personal computer (PC Pentium processor) through a developed c...

  8. Effect of Methyl tert-Butyl Ether in Standard Tests for Mutagenicity and Environmental Toxicity

    Czech Academy of Sciences Publication Activity Database

    Vosáhlíková, M.; Cajthaml, Tomáš; Demnerová, K.; Pazlarová, Jarmila

    2006-01-01

    Roč. 21, č. 6 (2006), s. 599-605. ISSN 1520-4081 Institutional research plan: CEZ:AV0Z50200510 Keywords : toxicity * mtbe * ames test Subject RIV: EE - Microbiology, Virology Impact factor: 1.582, year: 2006

  9. 76 FR 38026 - Diethylene Glycol Mono Butyl Ether; Exemption From the Requirement of a Tolerance

    Science.gov (United States)

    2011-06-29

    ... States Department of Agriculture (USDA) 1994-1996 and 1998 Nationwide Continuing Surveys of Food Intake.... There are no residual uncertainties identified in the exposure databases. The dietary food exposure... international food safety standards-setting organization in trade agreements to which the United States is...

  10. Green polymer chemistry VIII: synthesis of halo-ester-functionalized poly(ethylene glycol)s via enzymatic catalysis.

    Science.gov (United States)

    Castano, Marcela; Seo, Kwang Su; Kim, Eun Hye; Becker, Matthew L; Puskas, Judit E

    2013-09-01

    Halo-ester-functionalized poly(ethylene glycol)s (PEGs) are successfully prepared by the transesterification of alkyl halo-esters with PEGs using Candida antarctica lipase B (CALB) as a biocatalyst under the solventless conditions. Transesterifications of chlorine, bromine, and iodine esters with tetraethylene glycol monobenzyl ether (BzTEG) are quantitative in less than 2.5 h. The transesterification of halo-esters with PEGs are complete in 4 h. (1) H and (13) C NMR spectroscopy with MALDI-ToF and ESI mass spectrometry confirm the structure and purity of the products. This method provides a convenient and "green" process to effectively produce halo-ester PEGs. PMID:23877930

  11. Synthesis of thermoplastic poly(ester-olefin elastomers

    Directory of Open Access Journals (Sweden)

    Tanasijević Branka

    2004-01-01

    Full Text Available A series of thermoplastic poly(ester-olefin elastomers, based on poly(ethylene-stat-butylene, HO-PEB-OH, as the soft segment and poly (butylene terephthalate, PBT, as the hard segment, were synthesized by a catalyzed transesterification reaction in solution. The incorporation of soft hydrogenated poly(butadiene segments into the copolyester backbone was accomplished by the polycondensation of α, ω-dihydroxyl telechelic HO-PEB-OH, (PEB Mn = 3092 g/mol with 1,4-butanediol (BD and dimethyl terephthalate (DMT in the presence of a 50 wt-% high boiling solvent i.e., 1,2,4-trichlorobenzene. The molar ratio of the starting comonomers was selected to result in a constant hard to soft weight ratio of 60:40. The synthesis was optimized in terms of both the concentration of catalyst, tetra-n-butyl-titanate (Ti(OBu4, and stabilizer, N,N'-diphenyl-p-phenylenediamine (DPPD, as well as the reaction time. It was found that the optimal catalyst concentration (Ti(OBu4 for the synthesis of these thermoplastic elastomers was 1.0 mmol/mol ester and the optimal DPPD concentration was 1.0 wt-%. The extent of the reaction was followed by measuring the inherent viscosity of the reaction mixture. The effectiveness of the incorporation of the soft segments into the copolymer chains was proved by Soxhlet extraction with chloroform. The molecular structures, composition and the size of the synthesized poly(ester-butylenes were verified by 1H NMR spectroscopy, viscometry of dilute solutions and the complex dynamic melt viscosity. The thermal properties of poly(ester-olefins were investigated by differential scanning calorimetry (DSC. The degree of crystallinity was also determined by DSC. The thermal and thermo-oxidative stability were investigated by thermogravimetric analysis (TGA. The rheological properties of poly(ester-olefins were investigated by dynamic mechanical spectroscopy in the melt and solid state.

  12. Formation of secondary organic aerosol and oligomers from the ozonolysis of enol ethers

    Science.gov (United States)

    Sadezky, A.; Chaimbault, P.; Mellouki, A.; Römpp, A.; Winterhalter, R.; Le Bras, G.; Moortgat, G. K.

    2006-10-01

    Formation of secondary organic aerosol has been observed in the gas phase ozonolysis of a series of enol ethers, among them several alkyl vinyl ethers (AVE, ROCH=CH2), such as ethyl, propyl, n-butyl, iso-butyl, t-butyl vinyl ether, and ethyl propenyl ether (EPE, C2H5OCH=CHCH3). The ozonolysis has been studied in a 570 l spherical glass reactor at ambient pressure (730 Torr) and room temperature (296 K). Gas phase reaction products were investigated by in-situ FTIR spectroscopy, and secondary organic aerosol (SOA) formation was monitored by a scanning mobility particle sizer (SMPS). The chemical composition of the formed SOA was analysed by a hybrid mass spectrometer using electrospray ionization (ESI). The main stable gas phase reaction product is the respective alkyl formate ROC(O)H, formed with yields of 60 to 80%, implying that similar yields of the corresponding excited Criegee Intermediates (CI) CH2O2 for the AVE and CH3CHO2 for EPE are generated. Measured SOA yields are between 2 to 4% for all enol ethers. Furthermore, SOA formation is strongly reduced or suppressed by the presence of an excess of formic acid, which acts as an efficient CI scavenger. Chemical analysis of the formed SOA by ESI(+)/MS-TOF allows to identify oligomeric compounds in the mass range 200 to 800 u as its major constituents. Repetitive chain units are identified as CH2O2 (mass 46) for the AVE and C2H4O2 (mass 60) for EPE and thus have the same chemical compositions as the respective major Criegee Intermediates formed during ozonolysis of these ethers. The oligomeric structure and chain unit identity are confirmed by HPLC/ESI(+)/MS-TOF and ESI(+)/MS/MS-TOF experiments, whereby successive and systematic loss of a fragment with mass 46 for the AVE (and mass 60 for EPE) is observed. It is proposed that the oligomer has the following basic structure of an oligoperoxide, -[CH(R)-O-O]n-, where R=H for the AVE and R=CH3 for the EPE. Oligoperoxide formation is thus suggested to be another, so

  13. [Determination of three ester compounds in gasoline by two-dimensional gas chromatography].

    Science.gov (United States)

    Zhao, Yan; Xu, Dongyu; Lin, Haoxue; Chen, Xiaoyan; Chen, Zeyong

    2014-06-01

    A simple and efficient method based on the technique of packed column switching-back flushing was established for the analysis of the ester compounds (including ethyl acetate, sec-butyl acetate, dimethyl carbonate) in gasoline. With the use of a non-polar pre-column, we successfully separated the components in gasoline by back flushing out components heavier than n-octane, while the lighter components and the ester compounds were flushed into a polar analytical column. In this method, external standard method was applied for quantification. As a result, good linear relationships existed among the three ester compounds in the range of 50 mg/L to 50 000 mg/L. The linear correlation coefficients (r2) for ethyl acetate, sec-butyl acetate and dimethyl carbonate were 0.999 99, 1.000 00 and 0.999 95, respectively. The relative standard deviations (RSDs) of standard samples in six continuous tests were within 1.0%. The recoveries were between 98.7% and 107.9%. The detection limit of the method (S/N = 3) was 5 mg/L. No pretreatment was needed. This method is simple, accurate, quick as well as efficient, and can be used as an ideal method for the analysis of the ester compounds in gasoline. PMID:25269268

  14. 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

  15. Effects of ethylene glycol ethers on diesel fuel properties and emissions in a diesel engine

    International Nuclear Information System (INIS)

    Highlights: → Effect of ethylene glycol ethers on diesel fuel properties. → Effect of ethylene glycol ethers on diesel engine specific consumption and emissions. → Blends with ≤4 wt.% of oxygen do not change substantially diesel fuel quality. → 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, NOx, 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 oC). 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 NOx, both its behaviour and the sequence are opposite to that of CO.

  16. Recovering/recycling of butyl and halogenated butyl rubber via ionizing radiation

    International Nuclear Information System (INIS)

    Polymeric materials (plastics and rubbers) attain a continuous and raising proportion of urban and industrial scraps discarded in landfills; their impact on environment are more and more concerning. The implementation of new technologies in order to reduce impacts of plastic waste on the environment, at an effective cost, proved to be a great problem, due to inherent complexity for polymers re-using. Ionizing radiation is capable to modify structure and properties of polymeric material. Butyl and halobutyl rubbers have been used within a comprehensive scale, applications such as tires spare parts and diverse artifacts. The major high energy photon effect, as gamma-rays in butyl and halo butyl rubbers consists in free-radicals generation along changes in mechanical properties.This work aims to the development of controlled degradation processes (devulcanization) of butyl and halo butyl (chlorine and bromine) rubbers, in order to characterize their availability for transformation and modification of properties. Experimental results obtained showed that butyl and halobutyl rubbers,irradiated at 25 kGy and further sheared, are able to be used as an initial point for mixtures with pristine. (author)

  17. SYNTHESIS AND CRYSTALLIZATION BEHAVIOR OF POLY(ETHER ETHER KETONE ETHER KETONE) (PEEKEK)

    Institute of Scientific and Technical Information of China (English)

    Zhao-bin Qiu; Zhi-shen Mo; Ying-ning Yu; Hong-fang Zhang; Xian-hong Wang

    2000-01-01

    In this paper, the synthesis and crystallization behavior of poly(ether ether ketone ether ketone) (PEEKEK) are reported. PEEKEK was prepared from 4,4'-bis(p-fluorobenzoyl) diphenyl ether (4,4'-FBDE) and hydroquinone along the nucleophilic substitution route. The thermal properties were investigated by using DSC and TGA. The crystallization behavior of PEEKEK under several conditions, i.e., crystallization from the molten state (melt crystallization), crystallization from a quenched sample (cold crystallization) and crystallization induced by exposing glassy sample to methylene chloride (solvent-induced crystallization) has also been investigated. The results show that crystallization of PEEKEK could be induced by the above methods, and no polymorphism was found. The differences in the crystallization of PEEKEK induced by the above methods are seen in their degree of crystallinity.

  18. Formal [4+2] cycloaddition of di-tert-butyl 2-ethoxycyclobutane-1,1-dicarboxylate with ketones or aldehydes and tandem lactonization.

    Science.gov (United States)

    Okado, Ryohei; Nowaki, Aya; Matsuo, Jun-Ichi; Ishibashi, Hiroyuki

    2012-01-01

    A catalytic amount of tin(IV) chloride catalyzed formal [4+2] cycloaddition reaction of di-tert-butyl 2-ethoxycyclobutane-1,1-carboxylate with ketones or aldehydes to give diethyl 6-ethoxydihydro-2H-pyran-3,3(4H)-dicarboxylates, whereas two equivalents of trimethylsilyl triflate promoted tandem [4+2] cycloaddition and lactonization to afford 3-oxo-2,6-dioxabicyclo[2.2.2]octane-4-carboxylate esters. PMID:22223370

  19. Formal [4+2] Cycloaddition of di-tert-Butyl 2-Ethoxycyclobutane-1,1-dicarboxylate with Ketones or Aldehydes and Tandem Lactonization

    OpenAIRE

    Okado, Ryohei; Nowaki, Aya; Matsuo, Jun-ichi; Ishibashi, Hiroyuki

    2012-01-01

    A catalytic amount of tin(IV) chloride catalyzed formal [4+2] cycloaddition reaction of di-tert-butyl 2-ethoxycyclobutane-1,1-carboxylate with ketones or aldehydes to give diethyl 6-ethoxydihydro-2H-pyran-3,3(4H)-dicarboxylates, whereas two equivalents of trimethylsilyl triflate promoted tandem [4+2] cycloaddition and lactonization to afford 3-oxo-2,6-dioxabicyclo[2.2.2]octane-4-carboxylate esters.

  20. Method of making alkyl esters

    Science.gov (United States)

    Elliott, Brian

    2010-09-14

    Methods of making alkyl esters are described herein. The methods are capable of using raw, unprocessed, low-cost feedstocks and waste grease. Generally, the method involves converting a glyceride source to a fatty acid composition and esterifying the fatty acid composition to make alkyl esters. In an embodiment, a method of making alkyl esters comprises providing a glyceride source. The method further comprises converting the glyceride source to a fatty acid composition comprising free fatty acids and less than about 1% glyceride by mass. Moreover, the method comprises esterifying the fatty acid composition in the presence of a solid acid catalyst at a temperature ranging firm about 70.degree. C. to about 120.degree. C. to produce alkyl esters, such that at least 85% of the free fatty acids are converted to alkyl esters. The method also incorporates the use of packed bed reactors for glyceride conversion and/or fatty acid esterification to make alkyl esters.

  1. Metal ion complexation by ionizable crown ethers. Final report, January 1, 1988--June 30, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Bartsch, R.A.

    1994-12-31

    During the report period a variety of new lipophilic ionizable crown ethers with pendent proton-ionizable groups has been synthesized. The ligands possess one or more ionizable group (carboxylic acid, phosphonic acid monoethyl ester, para-nitrophenol, phosphonic acid) attached to crown ether, monoazacrown ether or diazacrown ether frameworks. These novel chelating agents have either pendent or inward-facing proton-ionizable groups. Such lipophilic proton-ionizable crown ethers are designed for use in multiphase metal ion separations (solvent extraction, liquid membrane transport). In addition a series of proton-ionizable crown ethers without lipophilic groups was prepared to study how structural variations within the ligand influence metal ion complexation in homogeneous media as assessed by NMR spectroscopy or titration calorimetry. A third class of new metal ion-complexing agents is a series of lipophilic acyclic polyether dicarboxylic acids. Competitive solvent extractions of alkali metal and alkaline earth cations and of the mixed species have been conducted to reveal the influence of ring size, nature and attachment site of the lipophilic group, sidearm length, and proton-ionizable group identity and location upon the selectivity and efficiency of metal ion complexation. In addition to such studies of structural variation within the lipophilic proton-ionizable crown ether, the effect of changing the organic solvent and variation of the stripping conditions have been assessed. The influence of structural variations within lipophilic acyclic polyether dicarboxylic acids upon competitive solvent extraction of alkaline earth cations has been probed. Also a new chromogenic, di-ionizable crown ether with extremely high selectivity for Hg{sup 2+} has been discovered.

  2. Synthesis, characterization and investigation of catalytic activity of Cu1−CoFe2O4 nanocatalysts in -butylation of -cresol

    Indian Academy of Sciences (India)

    Reza Fareghi Alamdari; Zahra Hosseinabadi; Masoud Farhadi Khouzani

    2012-07-01

    In this work, tertiary butylation of -cresol was carried out in the presence of Cu1−CoFe2O4 (x = 0 to 1) nanocatalysts by employing methyl-tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) as alkylation agents. Effects of temperature, mole ratio, type and catalyst composition, time and solvent in reaction conditions were investigated. These nanocatalysts were synthesized using hydrothermal method. The characterization of these catalysts was investigated by means of X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FT-IR). These nanocatalysts can be recovered and recycled. A good correlation was found between the activity, in terms of -cresol conversion and various product selectivities for this reaction, and also the acid-base properties of the catalysts. Nano-sized Cu0.5Co0.5Fe2O4, in comparison to the other nanocatalysts discussed in this report is the most active nanocatalyst. The only product of this reaction is 2--butyl -cresol with selectivity of 100% and -cresol conversion is 70%. The possible mechanism for this reaction system was discussed based on the reaction results. The reaction mechanism proposed involves the interaction of phenoxide from phenol and the tert-butyl cation from isobutene on Cu1−CoFe2O4.

  3. Enzymatic synthesis of lipophilic rutin and vanillyl esters from fish byproducts.

    Science.gov (United States)

    Mbatia, Betty; Kaki, Shiva Shanker; Mattiasson, Bo; Mulaa, Francis; Adlercreutz, Patrick

    2011-07-13

    Lipase-catalyzed synthesis of lipophilic phenolic antioxidants was carried out with a concentrate of n-3 polyunsaturated fatty acids (PUFAs), recovered from oil extracted from salmon ( Salmon salar ) byproduct. Vanillyl alcohol and rutin were selected for the esterification reaction, and obtained esters yields were 60 and 30%, respectively. The antioxidant activities of the esters were compared with those of commercial butylated hydroxytoluene (BHT) and α-tocopherol using DPPH radical scavenging and thiobarbituric acid assays. In the DPPH assay, rutin esters showed better activity than vanillyl esters, and on the contrary in lipophilic medium, vanillyl esters were found to be superior to rutin esters. In bulk oil system, the antioxidant activities of rutin and vanillyl derivatives were lower than that of BHT and α-tocopherol, but in emulsion, they showed better activity than α-tocopherol. By attaching to natural phenolics, the PUFAs are protected against oxidation, and PUFA improves the hydrophobicity of the phenolic, which could enhance its function in lipid systems. PMID:21630661

  4. Evaluation of the Phthalate Esters in South Indian Women with Endometriosis

    Directory of Open Access Journals (Sweden)

    with Endometriosis

    2008-01-01

    Full Text Available Background: To evaluate the possible association between phthalate esters (PEs and the occurrenceof endometriosis. Blood samples were collected from 99 infertile women with endometriosis (studygroup; 135 age-matched women without endometriosis (control group but with infertility relatedto tubal defects, fibroids, polycystic ovaries, idiopathic infertility and pelvic inflammatory diseasesdiagnosed by laparoscopy with no evidence of endometriosis or other gynecological disordersduring laparoscopic sterilization.Materials and Methods: This is a prospective case-control study, which recruited womenundergoing infertility treatment at three collaborating centers (BMMHRC: Bhagwan MahavirMedical Hospital and Research Centre, MHRT: Maternal Health and Research Trust, and OwaisiHospital and Research Center of Reproductive Medicine Hyderabad, which receives cases fromall over the region of Andhra Pradesh, India. The concentrations of Phthalate Esters were measuredby using the High Performance Liquid Chromatography (HPLC.Evaluation of Phthalate Esters concentrations in women with endometriosis compared with womenwho are free from the disease.Results: Women with endometriosis showed significantly higher concentrations of Phthalate esters(Dimethyl phthalate (DMP, Diethyl phthalate (DEP, Di-n-butyl phthalate (DnBP, Butyl benzylphthalate (BBP and Bis (2-ethylhexyl phthalate (BEHP compared with control group. Wefound that (38% of the cases with endometriosis and (21% of the control group. The correlationbetween the concentrations of Phthalate esters and different severity of endometriosis was strongand statistically significant at p<0.05 for all five compounds (DMP: r=+0.57, p<0.0001; DnBPr=+0.39, p<0.0001; BBP: r=+0.89, p<0.0001; DnOP: r=+0.66, p<0.0001 and BEHP: r=+0.33,p<0.0014.Conclusion: This study for the first time from Indian subcontinent demonstrates that possiblyPhthalate Esters might have a role in etiology of endometriosis.

  5. Design and Control of Glycerol-tert-Butyl Alcohol Etherification Process

    Directory of Open Access Journals (Sweden)

    Elena Vlad

    2012-01-01

    Full Text Available Design, economics, and plantwide control of a glycerol-tert-butyl alcohol (TBA etherification plant are presented. The reaction takes place in liquid phase, in a plug flow reactor, using Amberlyst 15 as a catalyst. The products' separation is achieved by two distillation columns where high-purity ethers are obtained and a section involving extractive distillation with 1,4-butanediol as solvent, which separates TBA from the TBA/water azeotrope. Details of design performed in AspenPlus and an economic evaluation of the process are given. Three plantwide control structures are examined using a mass balance model of the plant. The preferred control structure fixes the fresh glycerol flow rate and the ratio glycerol + monoether : TBA at reactor-inlet. The stability and robustness in the operation are checked by rigorous dynamic simulation in AspenDynamics.

  6. Structure-activity relationships of vanillic acid ester analogs in inhibitory effect of antigen-mediated degranulation in rat basophilic leukemia RBL-2H3 cells.

    Science.gov (United States)

    Ishimata, Nao; Ito, Hideyuki; Tai, Akihiro

    2016-08-01

    Methyl vanillate (1) showed strong degranulation inhibitory activity among vanillin derivatives tested. In order to find structure-activity relationships for developing anti-allergic agents with simple structures and potent activity, we synthesized several vanillic acid (VA) ester derivatives with C1-C4 and C8 alkyl chains and evaluated their degranulation inhibitory activities. The most active compound of VA ester derivatives was derivative 5 with a C4 straight alkyl chain, and derivative 5 exhibited approximately three-fold greater inhibitory activity than that of 1. Moreover, we designed 8 types of analogs based on 5, and we found that the minimum structure for potent degranulation inhibitory activity requires direct connection of the butyl ester moiety on the benzene ring and at least one hydroxyl group on the benzene ring. Butyl meta or para hydroxyl benzoate (10 or 11) has a simpler structure than that of 5 and exhibited more potent degranulation inhibitory activity than that of 5. PMID:27324979

  7. N-(Fluoren-9-ylmethoxycarbonyl-l-aspartic acid 4-tert-butyl ester

    Directory of Open Access Journals (Sweden)

    Kazuhiko Yamada

    2009-11-01

    Full Text Available The bond distances and bond angles of the title compound, C23H25NO6, are consistent with values typically found for fluoren-9-ylmethoxycarbonyl-protected amino acids. The conformations of the backbone and the side chain are slightly different from those of l-aspartic acid. The crystal structure exhibits two intermolecular hydrogen bonds, forming a two-dimensional sheet structure parallel to the ab plane.

  8. γ-Rays-induced synthesis of hydrogels of vinyl ethers with stimuli-sensitive behavior

    International Nuclear Information System (INIS)

    γ-Radiation method was applied to synthesize novel water-soluble and water-swelling polymers. Vinyl ether of ethylene glycol (VEEG), vinyl butyl (VBE) and vinyl isobutyl (VIBE) ethers were used as monomers. The synthesis of VEEG-VBE and VEEG-VIBE copolymers was carried out in a wide range of feed composition and absorbed dose. It was found that the hydrophobic-hydrophilic balance of the copolymers could be delicately varied by the copolymer composition as well as by the chemical structure of the alkyl substitute in the hydrophobic moiety. The copolymers exhibit thermo-sensitive behavior in water solutions. The value of transition temperature is considerably decreased at a higher concentration of the hydrophobic component in the copolymer composition

  9. Effects of gamma-ray irradiation on a cyanate ester/epoxy resin

    International Nuclear Information System (INIS)

    Effects of γ-ray irradiation on a cyanate ester/epoxy resin composed of dicyanate ester of bisphenol A (DCBA) and diglycidyl ether of bisphenol A (DGEBA) were investigated by changes in physicochemical and mechanical properties after the γ-ray irradiation with dose of 100 MGy as maximum at around 40 °C under vacuum. After the irradiation, gases of hydrogen, carbon monoxide and carbon dioxide were evolved, glass transition temperature decreased, and flexural strength also decreased. It was concluded that ether linkages bonded to cyanurate, isocyanurate and oxazolidinone structures are mainly decomposed by the irradiation. After 100 MGy irradiation, the flexural strength of DCBA/DGEBA was maintained more than 170 MPa which is 90% of initial value of 195 MPa. Flexural modulus and density slightly increased to the values of 3.9 GPa and 1.211 g/cm3 from initial values of 3.4 GPa and 1.199 g/cm3, respectively. - Highlights: • A cyanate ester/epoxy resin was irradiated by γ-rays with dose of 100 MGy in vacuum. • Viscoelastic property, structural change and gas evolution were investigated. • Ether linkages in the network structure were mainly decomposed by the irradiation. • The flexural strength of resin was maintained >170 MPa which is 90% of initial value

  10. The unsaturated simple ethers of glycerin

    International Nuclear Information System (INIS)

    To the unsaturated simple ethers of glycerin related allyl, vinyl ethers, which can be mono-, di- and three-substitutes. Besides there are known compounds, which contain simultaneously saturate and unsaturated radicals in molecule

  11. Development of the aza-crown ether metal complexes as artificial hydrolase.

    Science.gov (United States)

    Yu, Lan; Li, Fang-zhen; Wu, Jiao-yi; Xie, Jia-qing; Li, Shuo

    2016-01-01

    Hydrolases play a crucial role in the biochemical process, which can catalyze the hydrolysis of various compounds like carboxylic esters, phosphoesters, amides, nucleic acids, peptides, and so on. The design of artificial hydrolases has attracted extensive attention due to their scientific significance and potential applications in the field of gene medicine and molecular biology. Numerous macrocyclic metal complexes have been used as artificial hydrolase in the catalytic hydrolysis of the organic substrate. Aza-crown ether for this comment is a special class of the macrocyclic ligand containing both the nitrogen atoms and oxygen atoms in the ring. The studies showed that the aza-crown complexes exhibited high activity of hydrolytic enzyme. However, the aza-crown ether metal complex as artificial hydrolase is still very limited because of its difficulty in synthesis. This review summarizes the development of the aza-crown ether metal complexes as the artificial hydrolase, including the synthesis and catalysis of the transition metal complexes and lanthanide metal complexes of aza-crown ethers. The purpose of this review is to highlight: (1) the relationship between the structure and hydrolytic activity of synthetic hydrolase; (2) the synergistic effect of metal sites and ligands in the course of organic compound hydrolysis; and (3) the design strategies of the aza-crown ethers as hydrolase. PMID:26460062

  12. Effects of crown ethers and small amounts of cosolvent on the activity and enantioselectivity of α-chymotrypsin in organic solvents

    NARCIS (Netherlands)

    Engbersen, Johan F.J.; Broos, Jaap; Verboom, Willem; Reinhoudt, David N.

    1996-01-01

    Addition of crown ethers to α-chymotrypsin, subtilisin, and other proteases considerably enhances the activity of these enzymes in transesterification reactions of N-acetyl-alanine and -phenylalanine esters in organic solvents. Even much higher enhancements of activity (up to 640 ×) are obtained by

  13. The simple ethers of glycerin

    International Nuclear Information System (INIS)

    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

  14. Sintesis Metil Ester Sulfonat Dari Asam Stearat Dan Metil Ester Sulfonat Dari Asam Oleat

    OpenAIRE

    Samosir, Yustina

    2011-01-01

    The Synthesis of Methyl Ester Sulfonate (MES) from stearic acid and from oleic acid through the stages of esterification reaction, that are esterification from stearic acid and oleic acid that forms methyl ester stearic acid and methyl ester oleic acid next stage was sulfonating the two of methyl esters to form a methyl ester sulfonate stearic acid and methyl ester oleic acid sulfonate. Furthermore, both fatty acid methyl ester sulfonate is neutralized with NaOH to obtain sulfonate salt. ...

  15. The Benzyl Ester Group of Amino Acid Monomers Enhances Substrate Affinity and Broadens the Substrate Specificity of the Enzyme Catalyst in Chemoenzymatic Copolymerization.

    Science.gov (United States)

    Ageitos, Jose Manuel; Yazawa, Kenjiro; Tateishi, Ayaka; Tsuchiya, Kousuke; Numata, Keiji

    2016-01-11

    The chemoenzymatic polymerization of amino acid monomers by proteases involves a two-step reaction: the formation of a covalent acyl-intermediate complex between the protease and the carboxyl ester group of the monomer and the subsequent deacylation of the complex by aminolysis to form a peptide bond. Although the initiation with the ester group of the monomer is an important step, the influence of the ester group on the polymerization has not been studied in detail. Herein, we studied the effect of the ester groups (methyl, ethyl, benzyl, and tert-butyl esters) of alanine and glycine on the synthesis of peptides using papain as the catalyst. Alanine and glycine were selected as monomers because of their substantially different affinities toward papain. The efficiency of the polymerization of alanine and glycine benzyl esters was much greater than that of the other esters. The benzyl ester group therefore allowed papain to equally polymerize alanine and glycine, even though the affinity of alanine toward papain is substantially higher. The characterization of the copolymers of alanine and glycine in terms of the secondary structure and thermal properties revealed that the thermal stability of the peptides depends on the amino acid composition and resultant secondary structure. The current results indicate that the nature of the ester group drastically affects the polymerization efficiency and broadens the substrate specificity of the protease. PMID:26620763

  16. New Water-Soluble Carbamate Ester Derivatives of Resveratrol

    Directory of Open Access Journals (Sweden)

    Andrea Mattarei

    2014-10-01

    Full Text Available Low bioavailability severely hinders exploitation of the biomedical potential of resveratrol. Extensive phase-II metabolism and poor water solubility contribute to lowering the concentrations of resveratrol in the bloodstream after oral administration. Prodrugs may provide a solution—protection of the phenolic functions hinders conjugative metabolism and can be exploited to modulate the physicochemical properties of the compound. We report here the synthesis and characterization of carbamate ester derivatives of resveratrol bearing on each nitrogen atom a methyl group and either a methoxy-poly(ethylene glycol-350 (mPEG-350 or a butyl-glucosyl promoiety conferring high water solubility. Ex vivo absorption studies revealed that the butyl-glucosyl conjugate, unlike the mPEG-350 one, is able to permeate the intestinal wall. In vivo pharmacokinetics confirmed absorption after oral administration and showed that no hydrolysis of the carbamate groups takes place. Thus, sugar groups can be attached to resveratrol to obtain soluble derivatives maintaining to some degree the ability to permeate biomembranes, perhaps by facilitated or active transport.

  17. Preparation of sphingolipid fatty acid methyl esters for determination by gas-liquid chromatography.

    Science.gov (United States)

    MacGee, J; Williams, M G

    1981-01-30

    Sphingolipid fatty acids are first converted to a mixture of free acids and their n-butyl esters by heating the specimen at 85 degree C in aqueous butanolic hydrogen chloride; the butyl esters are then saponified with methanolic potassium hydroxide. After acidification and extraction into hexane, the fatty acids are extracted into a very small volume of aqueous trimethyl(m-trifluorotolyl)ammonium hydroxide (TMTFTH), injection of an aliquot of the TMTFTH extract into the gas chromatograph yields the fatty acid methyl esters by pyrolytic methylation of the quaternary ammonium salts of the fatty acids. The preparation of a specimen ready for the gas--liquid chromatographic (GLC) analysis with quantitative recovery of the sphingolipid fatty acids can be accomplished in less than 2 h. By comparison, none of a number of well-accepted techniques for the release of sphingomyelin fatty acids by hydrolysis or methanolysis released the fatty acids quantitatively in less than 3 h, and all required additional manipulations before GLC analysis. PMID:7217267

  18. Thermophysical properties of ionic liquid {1-butyl-3-methylimidazolium bromide [bmim][Br] in alkoxyalkanols + water} mixtures at different temperatures

    International Nuclear Information System (INIS)

    Highlights: ► Densities and speeds of sound of alkoxyalkanols in [bmim][Br]. ► Synthesis of room temperature ionic liquid [bmim][Br]. ► Partial molar volumes and compressibility of transfer. ► Apparent molar expansivities and the Hepler’s constant were calculated. ► Solute–solute and solute–solvent interactions and the structural changes of the solutes. - Abstract: The interactions of alkoxyalkanols with the ionic liquid 1-butyl-3-methylimidazolium bromide [bmim][Br] as a function of temperature were investigated by combination of volumetric and acoustic methods. The density, ρ, and speed of sound, u, of ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, and triethylene glycol monomethyl ether (0.00–1.01 mol·kg−1) in aqueous 1-butyl-3-methylimidazolium bromide solutions ranging from pure water to 0.29 mass% of ionic liquid have been measured at T = (288.15, 298.15 and 308.15) K and atmospheric pressure. The apparent molar volume (Vφ) and adiabatic compressibility (Kφ,S) of alkoxyalkanols in aqueous ionic liquid solution were determined at the measured temperatures. The partial molar volume (Vφ0) and partial molar adiabatic compressibility (Kφ0) of alkoxyalkanols at infinite dilution were evaluated. Transfer volumes (ΔVφ0) and transfer adiabatic compressibility (ΔKφ0) at infinite dilution from water to aqueous ionic liquid solution were also calculated. The temperature dependence of the apparent molar volume was used to calculate apparent molar expansivity (φE0) and the Hepler’s constant values, (∂2Vφ0/∂T2). The results were explained on the basis of competing patterns of interactions of co-solvent and the solute.

  19. A new alternative to expandable pedicle screws: Expandable poly-ether-ether-ketone shell.

    Science.gov (United States)

    Demir, Teyfik

    2015-05-01

    Screw pullout is a very common problem in the fixation of sacrum with pedicle screws. The principal cause of this problem is that the cyclic micro motions in the fixation of sacrum are higher than the other regions of the vertebrae that limit the osteo-integration between bone and screw. In addition to that, the bone quality is very poor at sacrum region. This study investigated a possible solution to the pullout problem without the expandable screws' handicaps. Newly designed poly-ether-ether-ketone expandable shell and classical pedicle screws were biomechanically compared. Torsion test, pullout tests, fatigue tests, flexion/extension moment test, axial gripping capacity tests and torsional gripping capacity tests were conducted in accordance with ASTM F543, F1798 and F1717. Standard polyurethane foam and calf vertebrae were used as embedding medium for pullout tests. Classical pedicle screw pullout load on polyurethane foam was 564.8 N compared to the failure load for calf vertebrae's 1264 N. Under the same test conditions, expandable poly-ether-ether-ketone shell system's pullout loads from polyurethane foam and calf vertebrae were 1196.3 and 1890 N, respectively. The pullout values for expandable poly-ether-ether-ketone shell were 33% and 53% higher than classical pedicle screw on polyurethane foam and calf vertebrae, respectively. The expandable poly-ether-ether-ketone shell exhibited endurance on its 90% of yield load. Contrary to poly-ether-ether-ketone shell, classical pedicle screw exhibited endurance on 70% of its yield load. Expandable poly-ether-ether-ketone shell exhibited much higher pullout performance than classical pedicle screw. Fatigue performance of expandable poly-ether-ether-ketone shell is also higher than classical pedicle screw due to damping the micro motion capacity of the poly-ether-ether-ketone. Expandable poly-ether-ether-ketone shell is a safe alternative to all other expandable pedicle screw systems on mechanical perspective

  20. Use of activated enol ethers in the synthesis of pyrazoles: reactions with hydrazine and a study of pyrazole tautomerism

    Directory of Open Access Journals (Sweden)

    Denisa Tarabová

    2014-04-01

    Full Text Available Activated enol ethers derived from esters or the dinitrile of malonic acid, or from pentane-2,4-dione were treated with hydrazine hydrate. The structures of the obtained products – pyrazoles 5 – were studied with a focus on tautomerism and supramolecular structure. A reverse addition of the reagents led to the isolation of two novel products, namely bis-enehydrazines 6 with an unsymmetrical arrangement of the formally equivalent subunits.

  1. Ether symmetry unification theory (ESU)

    International Nuclear Information System (INIS)

    The ether symmetry unification (ESU) theory postulates a mechanism that accounts for the formation of the universe as well as the formation of the original mass particles following the big bang. The essential role of the medium-vacuum of the theory of prerelativity is explained. The ultra-high energy particles described in the Ether Symmetry Unification Theory are compared with high energy magnetic monopoles described by Supersymmetry. Phase transitions of high energy events to low energy events and the associated media-vacua involved, postulated by the ESU, are then compared to the low energy events of the standard model within the critical phases of the first two seconds of quantum field theory's time line

  2. The free radical chemistry of tert-butyl formate: rate constants for hydroxyl radical, hydrated electron and hydrogen atom reaction in aqueous solution

    International Nuclear Information System (INIS)

    Transients generated in situ by advanced oxidation technologies (AOTs) to destroy organic contaminants in ground and drinking water often give large concentrations of chemical by-products. These by-products may have adverse health effects, and can also interfere with the desired chemical removal by competing for the generated transients, thus lowering the overall efficiency of the remediation process. To allow for a quantitative evaluation of the influence of tert-butyl formate (TBF), a major by-product formed in the AOT destruction of methyl tert-butyl ether, rate constants for TBF reaction with the hydroxyl radical, the hydrated electron and the hydrogen atom in aqueous solution were measured in this study. Absolute values of (5.23±0.07)x108, (5.48±0.09)x108 and (3.58±0.07)x106 M-1 s-1, were determined at 22 deg. C, respectively

  3. Thermal and enzymatic pretreatment of sludge containing phthalate esters prior to mesophilic anaerobic digestion

    DEFF Research Database (Denmark)

    Gavala, Hariklia N.; Yenal, U.; Ahring, Birgitte Kiær

    2004-01-01

    The present study aimed at investigating the effect of thermal pretreatment of sludge at 70degreesC on the anaerobic degradation of three commonly found phthalic acid esters (PAE): di-ethyl phthalate (DEP), di-butyl phthalate (DBP), and di-ethylhexyl phthalate (DEHP). Also, the enzymatic treatment...... at 28degreesC with a commercial lipase was studied as a way to enhance PAE removal. Pretreatment at 70degreesC of the sludge containing PAE negatively influenced the anaerobic biodegradability of phthalate esters at 37degreesC. The observed reduction of PAE biodegradation rates after the thermal...... orders of magnitude faster than under normal mesophilic anaerobic conditions. Moreover, the enzymatic treatment resulted in the shortest half-life of DEHP in sludge reported so far. Our study further showed that enzymatic treatment with lipases can be applied to raw sludge and its efficiency does...

  4. 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. PMID:16664206

  5. 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

  6. Synthesis and fungicidal activities of novel benzothiophene-substituted oxime ether strobilurins.

    Science.gov (United States)

    Tu, Song; Xie, Ya-Qiang; Gui, Si-Zhe; Ye, Li-Yi; Huang, Zi-Long; Huang, Yi-Bing; Che, Li-Ming

    2014-05-01

    Twenty-one novel benzothiophene-substituted oxime ether strobilurins, which employed a benzothiophene group to stabilise the E-styryl group in Enoxastrobin (an unsaturated oxime strobilurin fungicide developed by Shenyang Research Institute of Chemical Industry, China) were designed and synthesised. The biological assay indicated that most compounds exhibited good or excellent fungicidal activities, especially against Colletotrichum lagenarium and Puccinia sorghi Schw. In addition, methyl 3-methoxypropenoate oxime ethers and N-methoxy-carbamic acid methyl esters exhibited good in vivo fungicidal activities against Erysiphe graminis, Colletotrichum lagenarium and Puccinia sorghi Schw. under the tested concentrations. Notably, (E,E)-methyl 3-methoxy-2-(2-((((6-chloro-1-(1H-benzo[b]thien-2-yl)ethylidene)amino)oxy)methyl)phenyl)propenoate (5E) exhibited more potent in vivo fungicidal activities against nearly all of the tested fungi at a concentration of 0.39 mg/L compared to Enoxastrobin. PMID:24717155

  7. Solubilization of meso-carbon microbeads by potassium- or dibutylzinc-promoted butylation and structural analysis of the butylated products; Mesocarbon microbeads no butyl ka ni yoru kayoka to erareta butyl kabutsu no kozo kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Murata, S.; Zhang, Y.; Kidena, K.; Nomura, M. [Osaka University, Osaka (Japan). Faculty of Engineering

    1996-10-28

    Tetrahydrofuran (THF) solubility and structure of the butylated products of meso-carbon microbeads (MCMB) were studied experimentally. In experiment, MCMB-A and MCMB-B obtained from two kinds of coal-tar pitch were used as specimens. MCMBs were butylated by BZ method using dibutylzinc-butyl iodide and KT method using K-butyl iodide-THF, and the butylated products were successfully obtained. The butylated products were investigated through THF solubility test, {sup 13}C-NMR measurement and gel permeation chromatography (GPC) measurement. As the experimental result, a BZ method produced the butylated products at a yield of nearly 170%, while a KT method produced them at a yield of nearly 130%. The THF solubility was estimated to be 89-97%. As the study result of molecular weight distributions by GPC measurement of solvent solubles, the molecular weight of raw material MCMB was estimated to be 590-770 in terms of polystyrene. 6 refs., 2 figs., 1 tab.

  8. Ethermix process. Synthesis of ethers from CO/H{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Micheli, E.; Antonelli, G.B.; Sanfilippo, D. [Research Division, Snamprogetti S.p.A., S. Donato Milanese (Italy); Cometa, B.; Pecci, G.C. [Euron S.p.A., S. Donato Milanese (Italy)

    1997-12-31

    In the last two decades increasing interest has been devoted world-wide to the conversion of natural gas (NG) to valuable chemical products and fuels, due to its huge reserves and geographic distribution. In this paper with a multi-step process, under development, for the transformation of natural gas, particularly of methane, into ethers, mainly methyl t-butyl ether (MTBE). The process is performed in a series of steps that includes the preparation of a mixture of hydrogen and carbon monoxide in the desired ratio, their reaction addressed to the synthesis of a mixture of methanol and higher alcohols, mainly isobutanol, the dehydration of the higher alcohols fraction to olefins eventually followed by their reaction with methanol to produce the mixture of ethers. Economic evaluations of the process indicate high values of IRR and other indexes that allow the Ethermix technology to be the most convenient route for the transformation of NG into liquid products for motor fuel components. 5 refs.

  9. Evaluation of polymer inclusion membranes containing crown ethers for selective cesium separation from nuclear waste solution

    International Nuclear Information System (INIS)

    Transport behaviour of 137Cs from nitric acid feed was investigated using cellulose triacetate plasticized polymer inclusion membrane (PIM) containing several crown ether carriers viz. di-benzo-18-crown-6 (DB18C6), di-benzo-21-crown-7 (DB21C7) and di-tert-butylbenzo-18-crown-6 (DTBB18C6). The PIM was prepared from cellulose triacetate (CTA) with various crown ethers and plasticizers. DTBB18C6 and tri-n-butyl phosphate (TBP) were found to give higher transport rate for 137Cs as compared to other carriers and plasticizers. Effect of crown ether concentration, nitric acid concentration, plasticizer and CTA concentration on the transport rate of Cs was also studied. The Cs selectivity with respect to various fission products obtained from an irradiated natural uranium target was found to be heavily dependent on the nature of the plasticizer. The present work shows that by choosing a proper plasticizer, one can get either good transport efficiency or selectivity. Though TBP plasticized membranes showed good transport efficiency, it displayed poor selectivities. On the other hand, an entirely opposite separation behaviour was observed with 2-nitrophenyloctylether (NPOE) plasticized membranes suggesting the possible application of the later membranes for the removal of bulk 137Cs from the nuclear waste. The stability of the membrane was tested by carrying out transport runs for nearly 25 days.

  10. Hydroxytyrosyl alkyl ether derivatives inhibit platelet activation after oral administration to rats.

    Science.gov (United States)

    Muñoz-Marín, Javier; De la Cruz, José Pedro; Reyes, José Julio; López-Villodres, Juan Antonio; Guerrero, Ana; López-Leiva, Inmaculada; Espartero, José Luis; Labajos, María Teresa; González-Correa, José Antonio

    2013-08-01

    The low lipophilicity of hydroxytyrosol (HT) has motivated efforts to synthesize homologous series with better lipid solubility, such as the ethers, which are more lipophilic than HT. Because HT inhibits platelet aggregation, the aim of the study was to assess the possible anti-platelet effect of five HT ether derivatives (ethyl, butyl, hexyl, octyl and dodecyl) after oral administration to rats. Whole blood collagen-induced platelet aggregation and calcium-induced thromboxane B2 (TxB2), aortic 6-keto-prostaglandin F1α (6-keto-PGF1α) and nitrites+nitrates, plasma concentration of lipid peroxides (TBARS) and red blood cell content of reduced glutathione (GSH) were measured. The administration of 20 mg/kg/day inhibited platelet aggregation, TxB2 and TBARS in a non-linear manner related to the length of the carbon chain, with a cut-off effect in the hexyl derivative. Aortic nitrite and red blood cell GSH production were also increased. The aortic production of 6-keto-PGF1α was unaltered except in the group treated with the dodecyl derivative. The administration of 50 mg/kg/day showed a similar pharmacodynamic profile but without the non-linear effect. In conclusion, HT ethers, especially the hexyl derivative, are a potential alternative to hydroxytyrosol, and their effect merits additional research to determine their role in the prophylaxis of vascular disease. PMID:23643702

  11. Aggregation of Dodecyl 1-Pyrenylmethyl Ether and Its Application in Structure-Polarity Relations of Aggregates

    Institute of Scientific and Technical Information of China (English)

    SANG,Da-Yong; TIAN,Juan; JI,Guo-Zhen

    2006-01-01

    The aggregation behavior of dodecyl 1-pyrenylmethyl ether was studied in dioxane-water mixture solvents by fluorescence techniques. The labeled pyrenyl group was effective in monitoring the polarity change of its environment during aggregation processes. Based on the structural effects such as chain-length effect, self-coiling effect,and branch-group effect on the polarity of the probe environment, the structure features of aggregates were discussed and have been used to interpret the effect of the structural features on the aggregates formed by three cholesteryl esters and three long chain alkanes.

  12. Flow-Induced Crystallization of Poly(ether ether ketone)

    Science.gov (United States)

    Nazari, Behzad; Rhoades, Alicyn; Colby, Ralph

    The effects of an interval of shear above the melting temperature Tm on subsequent isothermal crystallization below Tm is reported for the premier engineering thermoplastic, poly(ether ether ketone) (PEEK). The effect of shear on the crystallization rate of PEEK is investigated by means of rheological techniques and differential scanning calorimetry (DSC) under a protocol of imposing shear in a rotational cone and plate rheometer and monitoring crystallization after quenching. The rate of crystallization at 320 °C was not affected by shear for shear rates <7 s-1 at 350 °C, whereas intervals of adequate shear at higher shear rates prior to the quench to 320 °C accelerated crystallization significantly. As the duration of the interval of shear above 7 s-1 is increased, the crystallization time decreases but at each shear rate eventually saturates once the applied specific work exceeds ~120 MPa. The annealing of the flow-induced precursors was also investigated. The nuclei were fairly persistent at temperatures close to 350 °C, however very unstable at temperatures above 375 °C. This suggests that the nanostructures formed under shear might be akin to crystalline lamellae of greater thickness, compared to quiescently crystallized lamellae.

  13. tert-Butyl N-[2-(N-isobutyl-4-meth­oxy­benzene­sulfonamido)­eth­yl]carbamate

    OpenAIRE

    Xiao-Guang Bai; Ju-Xian Wang

    2014-01-01

    The title compound, C18H30N2O5S, was synthesized by the reaction of tert-butyl 2-(iso­butyl­amino)­ethyl­carbamate with p-meth­oxy­phenyl­sulfonyl chloride. In the mol­ecule, two intra­molecular C—H⋯O hydrogen bonds are observed. In the crystal, mol­ecules are linked by N—H⋯O hydrogen bonds involving the imino group N atom and the ester group O atom into chains running parallel to the b axis. The chains are further connected by C—H⋯O hydrogen bonds, forming layers parallel to the bc plane....

  14. Environmental effect of rapeseed oil ethyl ester

    International Nuclear Information System (INIS)

    Exhaust emission tests were conducted on rapeseed oil methyl ester (RME), rapeseed oil ethyl ester (REE) and fossil diesel fuel as well as on their mixtures. Results showed that when considering emissions of nitrogen oxides (NOx), carbon monoxide (CO) and smoke density, rapeseed oil ethyl ester had less negative effect on the environment in comparison with that of rapeseed oil methyl ester. When fuelled with rapeseed oil ethyl ester, the emissions of NOx showed an increase of 8.3% over those of fossil diesel fuel. When operated on 25-50% bio-ester mixed with fossil diesel fuel, NOx emissions marginally decreased. When fuelled with pure rapeseed oil ethyl ester, HC emissions decreased by 53%, CO emissions by 7.2% and smoke density 72.6% when compared with emissions when fossil diesel fuel was used. Carbon dioxide (CO2) emissions, which cause greenhouse effect, decreased by 782.87 g/kWh when rapeseed oil ethyl ester was used and by 782.26 g/kWh when rapeseed oil methyl ester was used instead of fossil diesel fuel. Rapeseed oil ethyl ester was more rapidly biodegradable in aqua environment when compared with rapeseed oil methyl ester and especially with fossil diesel fuel. During a standard 21 day period, 97.7% of rapeseed oil methyl ester, 98% of rapeseed oil ethyl ester and only 61.3% of fossil diesel fuel were biologically decomposed. (author)

  15. Avocado and olive oil methyl esters

    International Nuclear Information System (INIS)

    Biodiesel, the mono-alkyl esters of vegetable oils, animal fats or other triacylglycerol-containing materials and an alternative to conventional petroleum-based diesel fuel, has been derived from a variety of feedstocks. Numerous feedstocks have been investigated as potential biodiesel sources, including commodity oils, however, the methyl esters of avocado and olive oil would likely be suitable as biodiesel fuel. In order to expand the database and comprehensive evaluation of the properties of vegetable oil esters, in this work the fuel-related properties of avocado and olive oil methyl esters, which exhibit similar fatty acid profiles including high oleic acid content, are determined. The cetane numbers of avocado oil methyl esters and olive oil methyl esters are relatively high, determined as 59.2 and 62.5, respectively, due to their elevated content of methyl oleate. Other properties are well within the ranges specified in biodiesel standards. The cloud points of both esters are slightly above 0 °C due to their content of saturated esters, especially methyl palmitate. Overall, avocado and olive oil yield methyl esters with fuel properties comparable to methyl esters from other commodity vegetable oils. The 1H and 13C NMR spectra of avocado and olive oil methyl esters are reported. -- Highlights: • Methyl esters of avocado and olive oil meet biodiesel fuel standards. • Provides comparison for methyl esters of other vegetable oils with high oleic content. • Discusses and compares present results with prior literature

  16. Multistage equilibrium in Eu(fod)3-crown ether 18-C-6. Study by the PMR method

    International Nuclear Information System (INIS)

    Dependence of PMR shifts of Eu(fod)3 and 18-C-6 protons on the composition of the substances solution in CCl4 at 20 deg C is investigated. It is shown that alongside with complexes of shifting reagent with crown-ether of the composition RS and RS2 (R - shifting reagent, S - crown ether) self-associated complexes of shifting reagent of the composition R2 and R3 are present in solutions in considerable amounts. Formation constants and shifts for all the complexes are determined. High values of weak-pole shifts for protons of tert.-butyl groups in self-associates R2 and R3 points to the formation of structures comprising bridge fragments Eu-O-Eu

  17. Radioiodinated cholesteryl ester analogs as residualizing tracers of lipoproteins disposition

    International Nuclear Information System (INIS)

    Due to the importance of low density lipoprotein (LDL) in lipid metabolism and atherosclerosis, efforts were made to incorporate 125I-cholesteryl iopanoate (125I-CI), a residualizing cholesteryl ester (CE) analog, into the lipid core of LDL. This preparation is potentially useful as a scintigraphically detectable tracer of LDL uptake into atheroma and tissues such as the adrenal and liver. Initial studies using a cholesterol-fed rabbit model of atherosclerosis validated the use of 125I-CI as a tracer of CE deposition. However, scintigraphy revealed considerable nonspecific 125I-CI uptake due to tissue cholesterol loading. An alternative animal model was the guinea pig, which responds moderately to cholesterol feeding and carries the plasma cholesterol predominantly as LDL. Dietary fat and cholesterol, coupled with chronic aortic injury caused by an indwelling catheter, resulted in lipid containing, smooth muscle cell proliferative lesions in many animals. However, further studies are necessary to fully characterize this model. In additional studies, in vitro methods for incorporating 125I-CI into LDL were examined. These included a reconstitution procedure described by Krieger et al. and a procedure involving incubation of detergent (Tween 20)-solubilized 125I-CI with plasma. Although both LDL preparations were taken up normally by cultured fibroblasts, the plasma clearance rate of reconstituted LDL was markedly abnormal in guinea pigs. In contrast, LDL labeled by the detergent method cleared from the plasma identically to a radioiodinated LDL control. Therefore, this latter procedure was also used to incorporate two novel radioiodinated cholesteryl ether analogs 125I-CI cholesteryl m-iodobenzyl ether [125I-CIDE] and 125I-cholesteryl 12-(miodophenyl)dodecyl ether [125I-CIDE] into LDL

  18. 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.

  19. NMR spectra of phosphorus 17O esters

    International Nuclear Information System (INIS)

    By the 17O NMR method the authors investigated methyl, ethyl, isopropyl, tert-butyl, and phenyl ethylene phosphites; methyl, ethyl, and isopropyl trimethylene phosphites; and methyl, ethyl, isopropyl, and tert-butyl o-phenylene phosphites. They also determined the 13C and 31P NMR spectra of these compounds

  20. The reorientation of t-butyl groups in butylated hydroxytoluene: A deuterium nuclear magnetic resonance spectral and relaxation time study

    Science.gov (United States)

    Polson, James M.; Fyfe, J. D. Dean; Jeffrey, Kenneth R.

    1991-03-01

    Deuterium nuclear magnetic resonance (NMR) spectra and spin-lattice relaxation times were determined in order to study the dynamics of t-butyl groups in butylated hydroxytoluene. The results are consistent with a model first proposed by Beckmann et al. [J. Magn. Reson. 36, 199 (1979)], where there is an inequivalence between the methyl groups within each t-butyl group. While two methyl groups reorient rapidly relative to the whole t-butyl rotation, the remaining methyl group is more restricted in its motion, reorienting at a rate comparable to that of the t-butyl group itself. The spin-lattice relaxation data show two T1 minima, the high temperature minimum (40 °C) corresponding to the combined t-butyl and ``slow'' methyl rotations, and the low temperature minimum corresponding to ``fast'' methyl group rotation. Using an explicitly defined T1 fitting function, the T1 data yield activation energies of 2.2 and 6.0 kcal/mol for the fast methyl and t-butyl rotations, respectively, both in agreement with Beckmann's values obtained from proton T1 experiments. It was also possible to simulate the low temperature deuterium NMR spectra from T=-160 °C to T=-80 °C using the aforementioned dynamical inequivalence between the t-butyl methyl groups. While the fast methyl group rotation was in the motional narrowing region for T>-160 °C, it was possible, from the simulations, to determine the t-butyl exchange rates to within 10%. The jump rates are remarkably close to the values predicted from the T1 results. Above -80 °C, the spectra could not be simulated, implying that a third motion must be present to further alter the high temperature line shapes. The effective axial asymmetry of the T>-20° spectra indicates that the additional motion involves a two site exchange.

  1. Synthesis of substituted 2-cyanoarylboronic esters

    DEFF Research Database (Denmark)

    Lysén, Morten; Hansen, Henriette M; Begtrup, Mikael; Kristensen, Jesper L

    2006-01-01

    The synthesis of substituted 2-cyanoarylboronic esters is described via lithiation/in situ trapping of the corresponding methoxy-, trifluoromethyl-, fluoro-, chloro-, and bromobenzonitriles. The crude arylboronic esters were obtained in high yields and purities and with good regioselectivities....

  2. Atmospheric lifetimes of selected fluorinated ether compounds

    DEFF Research Database (Denmark)

    Heathfield, A.E.; Anastasi, C.; Pagsberg, Palle Bjørn;

    1998-01-01

    Atmospheric lifetimes have been estimated for a selection of ethers, the latter representing a class of compounds being considered as replacements for chlorofluorocarbons. The estimates are based on laboratory measurements of rate constants for the reaction of the OH radical with the ethers, and ...

  3. Unitary information ether and its possible applications

    International Nuclear Information System (INIS)

    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.)

  4. Emulsion Polymerization of Butyl Acrylate: Spin Trapping and EPR Study

    Science.gov (United States)

    Kim, S.; Westmoreland, D.

    1994-01-01

    The propagating radical in the emulsion polymerization reaction of butyl acrylate was detected by Electron Paramagnetic Resonance spectroscopy using two spin trapping agents, 2-methyl-2nitrosopropane and alpha -N-tert-butylnitrone.

  5. Synthesis of highly reactive polyisobutylene catalyzed by EtAlCl 2/Bis(2-chloroethyl) ether soluble complex in hexanes

    KAUST Repository

    Kumar, Rajeev Ananda

    2014-03-25

    The polymerization of isobutylene (IB) to yield highly reactive polyisobutylene (HR PIB) with high exo-olefin content using GaCl3 or FeCl3·diisopropyl ether complexes has been previously reported.1 In an effort to further improve polymerization rates and exo-olefin content, we have studied ethylaluminum dichloride (EADC) complexes with diisopropyl ether, 2-chloroethyl ethyl ether (CEEE), and bis(2-chloroethyl) ether (CEE) as catalysts in conjunction with tert-butyl chloride as initiator in hexanes at different temperatures. All three complexes were readily soluble in hexanes. Polymerization, however, was only observed with CEE. At 0 °C polymerization was complete in 5 min at [t-BuCl] = [EADC·CEE] = 10 mM and resulted in PIB with ∼70% exo-olefin content. Studies on complexation using ATR FTIR and 1H NMR spectroscopy revealed that at 1:1 stoichiometry a small amount of EADC remains uncomplexed. By employing an excess of CEE, exo-olefin contents increased up to 90%, while polymerization rates decreased only slightly. With decreasing temperature, polymerization rates decreased while molecular weights as well as exo-olefin contents increased, suggesting that isomerization has a higher activation energy than β-proton abstraction. Density functional theory (DFT) studies on the Lewis acid·ether binding energies indicated a trend consistent with the polymerization results. The polymerization mechanism proposed previously for Lewis acid·ether complexes1 adequately explains all the findings. © 2014 American Chemical Society.

  6. Biodiesel With Optimized Fatty Ester Composition

    Science.gov (United States)

    Biodiesel is largely composed of the mono-alkyl esters, usually methyl esters, of vegetable oils or animal fats with its fatty acid profile corresponding to that of the parent oil or fat. The different fatty esters have varying properties of relevance to biodiesel. The feedstock-dependent variatio...

  7. DI-2-ETHYLHEXYL PHTHALATE AND DI-N-BUTYL PHTHALATE IN TISSUES OF COMMON CARP (Cyprinus Carpio L.) AFTER HARVEST AND AFTER STORAGE IN FISH STORAGE TANKS

    OpenAIRE

    Vlasta Stancová; Lenka Puškárová; Alžbeta Jarošová

    2011-01-01

    The aim of the present study was to determine whether the influence of fish pond and fish storage tank conditions change the content of phthalic acid esters (di-n-butyl phthalate (DBP) and di-2-ethylhexyl phthalate (DEHP)) in the carcass of the Common carp. Samples obtained from the autumn harvest of two fish ponds (R1 and R2) in 2007 and 2010 from the South Moravia and after a seven-week-long storage in fish storage tanks were analyzed. It was found that in the samples (2007) from both fish ...

  8. SURGICAL MANAGEMENT OF CONGENITAL VASCULAR ANOMALIES WITH N BUTYL CYANOACRYLATE

    OpenAIRE

    Rajendra Prasad; Biswajit

    2015-01-01

    BACKGROUND: Congenital vascular malformation is stressful both to the patient and the treating physician. Use of sclerosing agent followed by surgical excision has been used by many. In our study we have used percutaneous injection of N - butyl cyanoacrylate (NBCA) in such lesions to make these lesions a menable to easy excision. N Butyl Cyanoacrylate (NBCA) is a rapidly hardening liquid adhesive often referred to as glue. The substance polymerizes immediately...

  9. Tailoring the toughness and CTE of high temperature bisphenol E cyanate ester (BECy resin

    Directory of Open Access Journals (Sweden)

    M. Thunga

    2014-05-01

    Full Text Available The objective of the present work is to enhancing the toughness and minimizing the CTE of a special class of bisphenol E cyanate ester (BECy resin by blending it with a thermoplastic toughening agent. Poly(ether sulfone was chosen as a high temperature resistant thermoplastic resin to enhance the thermo-mechanical properties of BECy. The influence of poly(ether sulfone/BECy blend composition on the morphology and phase behavior was studied using scanning electron microscopy and dynamic mechanical analysis. The mechanical properties of the blends were evaluated by flexural tests, which demonstrated significant enhancement in the material’s toughness with an increase in PES concentration from 0 to 15 wt%. The coefficient of thermal expansion of pure BECy was reduced from 61 to 48 ppm/°C in the blends with PES, emphasizing the multi-functional benefits of PES as a toughening agent in BECy.

  10. Cytotoxicity and genotoxicity of butyl cyclohexyl phthalate.

    Science.gov (United States)

    Köksal, Çinel; Nalbantsoy, Ayse; Karabay Yavaşoğlu, N Ülkü

    2016-03-01

    Butyl cyclohexyl phthalate (BCP) is frequently used in personal care products, medical and household applications. The aim of this study is therefore to evaluate possible cytotoxicity and genotoxicity of BCP using in vitro and in vivo assays. The in vitro cytotoxic effect of BCP was investigated on mouse fibroblastic cell line (L929 cells) by MTT assay. The result showed that BCP inhibits cell proliferation in a concentration-dependent manner (IC50 value = 0.29 µg/mL). For genotoxicity assessment, tested concentrations of BCP demonstrated mutagenic activity in the presence of S9 mix with the Salmonella strain TA100 in the Ames test. Results showed that BCP is a secondary mutagenic substance even in low concentrations. The data obtained from 28-days repeated toxicity tests on mice revealed that BCP caused abnormalities of chromosome number, in a dose-dependent manner. Additionally, DNA damage, particularly DNA strand breaks, was assessed by Comet assay. The test result shows that BCP seemed to have genotoxic potential at a high level of exposure. PMID:25501535

  11. Radiation degradation of spent butyl rubbers

    Science.gov (United States)

    Telnov, A. V.; Zavyalov, N. V.; Khokhlov, Yu. A.; Sitnikov, N. P.; Smetanin, M. L.; Tarantasov, V. P.; Shadrin, D. N.; Shorikov, I. V.; Liakumovich, A. L.; Miryasova, F. K.

    2002-03-01

    Radiation methods of materials modification applied in technological chains can have significant economical and ecological advantages as compared to the established chemical, thermal and mechanical methods. Each year the problems of nature resources economy through the use of production and consumption wastes acquire a more significant value, as it allows to solve also ecological issues along with economical ones. This is mostly acute in relation to polymeric systems based on saturated rubbers, for example butyl rubber (BR) used in the tyre industry, as due to their high resistance to the action of oxygen, ozone, solar radiation and bacteria, they contaminate the environment for rather a long period. At VNIIEF and KSPU experiments were carried out on application of electron beams with energy from 6 to 10 MeV for radiation destruction of spent rubber based on BR. The radiation-degraded material was tested for re-use in the formulation of initial diaphragm mixture, rubber mixture for producing rubberized fabric and roofing.

  12. Radiation degradation of spent butyl rubbers

    International Nuclear Information System (INIS)

    Radiation methods of materials modification applied in technological chains can have significant economical and ecological advantages as compared to the established chemical, thermal and mechanical methods. Each year the problems of nature resources economy through the use of production and consumption wastes acquire a more significant value, as it allows to solve also ecological issues along with economical ones. This is mostly acute in relation to polymeric systems based on saturated rubbers, for example butyl rubber (BR) used in the tyre industry, as due to their high resistance to the action of oxygen, ozone, solar radiation and bacteria, they contaminate the environment for rather a long period. At VNIIEF and KSPU experiments were carried out on application of electron beams with energy from 6 to 10 MeV for radiation destruction of spent rubber based on BR. The radiation-degraded material was tested for re-use in the formulation of initial diaphragm mixture, rubber mixture for producing rubberized fabric and roofing

  13. NQR in tert-butyl chloride

    Science.gov (United States)

    Brunetti, Aldo H.

    2004-03-01

    Tert-butyl chloride has been broadly studied experimentally through various techniques such as X-ray crystallography, DTA, and NMR. It was also studied experimentally through nuclear quadrupole resonance (NQR), but this study was limited and incomplete. In this paper, we present a more detailed study of TBC through the NQR of 35Cl. Our results show that near 120 K, the onset of the CH 3 groups semirotations around symmetry axis C3 takes place with an activation energy U=16.1 kJ mol -1. This intramolecular movement produces a T1 minimum near 148 K and is the dominant mechanism of the nuclear spin-lattice relaxation in phase III of this compound. In phase II of TBC, we show that there are not only methyl groups semirotations, but also semirotations of the whole molecule around a different axis from the symmetry axis C' 3 (C-Cl bond) with an activation energy of E=10.4 kJ mol -1.

  14. GC/GCMS analysis of the petroleum ether and dichloromethane extracts of Moringa oleifera roots

    Institute of Scientific and Technical Information of China (English)

    Shaheen Faizi; Saima Sumbul; Muhammed Ali Versiani; Rubeena Saleem; Aisha Sana; Hira Siddiqui

    2014-01-01

    Objective:To explore the phytochemical constituents from petroleum ether and dichloromethane extracts of Moringa oleifera (M. oleifera) roots using GC/GC-MS. Methods: A total of 5.11 kg fresh and undried crushed root of M. oleifera were cut into small pieces and extracted with petroleum ether and dichloromethane (20 L each) at room temperature for 2 d. The concentrated extracts were subjected to their GC-MS analysis. Results:The GC-MS analysis of the petroleum ether and dichloromethane extracts of M. oleifera roots, which showed promising biological activities, has resulted in the identification 102 compounds. These constituents belong to 15 classes of compounds including hydrocarbons, fatty acids, esters, alcohols, isothiocyanate, thiocyanate, pyrazine, aromatics, alkamides, cyanides, steroids, halocompounds, urea and N-hydroxyimine derivatives, unsaturated alkenamides, alkyne and indole. GC/GC-MS studies on petroleum ether extract of the roots revealed that it contained 39 compounds, belonging to nine classes. Cyclooctasulfur S8 has been isolated as a pure compound from the extract. The major compounds identified from petroleum ether extract were trans-13-docosene (37.9%), nonacosane (32.6%), cycloartenol (28.6%) nonadecanoic acid (13.9%) and cyclooctasulfur S8 (13.9%). Dichloromethane extract of the roots was composed of 63 compounds of which nasimizinol (58.8%) along with oleic acid (46.5%), N-benzyl-N-(7-cyanato heptanamide (38.3%), N-benzyl-N-(1-chlorononyl) amide (30.3%), bis [3-benzyl prop-2-ene]-1-one (19.5%) and N, N-dibenzyl-2-ene pent 1, 5-diamide (11.6%) were the main constituents. Conclusions:This study helps to predict the formula and structure of active molecules which can be used as drugs. This result also enhances the traditional usage of M. oleifera which possesses a number of bioactive compounds.

  15. Effect of Butylated Hydroxytoluene and Butylated Hydroxyanisole on Some Properties of Kidney Fat and Tail Fat During Frozen Storage

    OpenAIRE

    ATAY, Ömür

    1998-01-01

    Some physical and chemical properties of kidney fat (obtained from cattle) and tail fat (obtained from sheep) were determined in this study. Effects of butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA) and BHT+BHA on free fatty acids (FFA) contents, thiobarbituric acid (TBA) values and peroxide number were also examined during frozen storage at -18°C for 9 months. The following values were determined for kidney fat; melting point 47°C, saponification number 193, iodine number...

  16. Thyroid Disruption by Di-n-Butyl Phthalate (DBP) and Mono-n-Butyl Phthalate (MBP) in Xenopus laevis

    OpenAIRE

    Shen, Ouxi; Wu, Wei; Du, Guizhen; Liu, Renping; Yu, Lugang; Sun, Hong; Han, Xiumei; Jiang, Yi; Shi, Wei; Hu, Wei; Song, Ling; Xia, Yankai; Wang, Shoulin; Wang, Xinru

    2011-01-01

    Background Di-n-butyl phthalate (DBP), a chemical widely used in many consumer products, is estrogenic and capable of producing seriously reproductive and developmental effects in laboratory animals. However, recent in vitro studies have shown that DBP and mono-n-butyl phthalate (MBP), the major metabolite of DBP, possessed thyroid hormone receptor (TR) antagonist activity. It is therefore important to consider DBP and MBP that may interfere with thyroid hormone system. Methodology/Principal ...

  17. Preparation and in vivo evaluation of 99mTcN-tertiary butyl xanthate as a potential myocardial agent

    International Nuclear Information System (INIS)

    99mTc-tertiary butyl isonitrile (TBI), a complex structurally similar to 99mTc-sestamibi, has been reported to be taken up in the myocardium, albeit with significant retention in liver and lungs, thereby leading to obscure heart images when used for in vivo imaging. In the present study, tert-butyl xanthate, which is similar to TBI, but possesses two sulphur donors, has been synthesized in excellent yield by reacting tert-butanol with carbon disulphide and sodium hydroxide in dry ether. The prepared ligand was then labeled with [99mTcN]2+ core and the resultant complex was characterized by paper electrophoresis and HPLC. The complex was obtained in more than 95% yield and was found to be neutral. The preparation was evaluated in Swiss mice for its myocardial perfusion characteristics. The maximum heart uptake observed was 2.34%ID/g at 5 min p.i., which was cleared rapidly, with retention of 0.50%ID/g of the activity at 60 min p.i. However, owing to slow clearance from blood, liver and lungs, the heart/blood, heart/liver and heart/lung ratios at all the time points of study were not significantly high

  18. Toxicity of phosphor esters: Willy Lange (1900-1976) and Gerda von Krueger (1907-after 1970).

    Science.gov (United States)

    Petroianu, G A

    2010-10-01

    In 1851 Williamson serendipitously discovered a new and efficient way to produce ethers using ethyl iodide and potassium salts. Based on this new synthetic approach, the Frenchman Philippe de Clermont and the Muscovite Wladimir Moschnin, both élèves of Adolphe Wurtz in his Paris School of Chemistry, achieved the synthesis of the first ester of pyrophosphoric acid (TEPP). de Clermont "tasted" the new compound and although TEPP is a potent cholinesterase inhibitor he failed to recognize its toxicity. Almost a century later, in 1932, Willy Lange (1900-1976) and his graduate student Gerda v. Krueger (1907-after 1970) described the toxicity of organophosphonates. While the classic paper of the two "Uber Ester der Monofluorphosphorsäure." is cited by almost everybody working in the field, little is known about Lange and almost nothing about v. Krueger. This brief communication attempts to shed some light on the life of both. PMID:21105582

  19. Bioreversible Derivatives of Phenol. 2. Reactivity of Carbonate Esters with Fatty Acid-like Structures Towards Hydrolysis in Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Claus Larsen

    2007-10-01

    Full Text Available A series of model phenol carbonate ester prodrugs encompassing derivatives with fatty acid-like structures were synthesized and their stability as a function of pH (range 0.4 – 12.5 at 37°C in aqueous buffer solutions investigated. The hydrolysis rates in aqueous solutions differed widely, depending on the selected pro-moieties (alkyl and aryl substituents. The observed reactivity differences could be rationalized by the inductive and steric properties of the substituent groups when taking into account that the mechanism of hydrolysis may change when the type of pro-moiety is altered, e.g. n-alkyl vs. t-butyl. Hydrolysis of the phenolic carbonate ester 2-(phenoxycarbonyloxy-acetic acid was increased due to intramolecular catalysis, as compared to the derivatives synthesized from ω-hydroxy carboxylic acids with longer alkyl chains. The carbonate esters appear to be less reactive towards specific acid and base catalyzed hydrolysis than phenyl acetate. The results underline that it is unrealistic to expect that phenolic carbonate ester prodrugs can be utilized in ready to use aqueous formulations. The stability of the carbonate ester derivatives with fatty acid-like structures, expected to interact with the plasma protein human serum albumin, proved sufficient for further in vitro and in vivo evaluation of the potential of utilizing HSA binding in combination with the prodrug approach for optimization of drug pharmacokinetics.

  20. Instrumental laboratories based on the analysis of butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA)

    Science.gov (United States)

    Wiginton, John Franklin

    A semester-long series of instrumental analysis laboratory activities appropriate for advanced undergraduate and graduate students is described. The activities incorporate five analytical instruments commonly found in post-secondary educational, industrial, and governmental laboratories: a gas chromatograph with a flame ionization detector (GC), a gas chromatograph with a mass specific detector (GC/MS), a high-pressure liquid chromatograph with a UV-Visible detector (HPLC), a high-performance liquid chromatograph with a mass specific detector (LC/MS), and a nuclear magnetic resonance spectrometer (NMR). The series of activities utilizes two analytes, butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA), which are qualitatively and quantitatively analyzed, then structurally characterized. The protocol for each laboratory activity directs students to accomplish a specific analysis in the most efficient manner, but leaves the actual procedure vague enough to give the student a chance to experiment with the instrument. Student success is assessed by two means, having the student submit a detailed journal-style lab report and a class-wide discussion regarding the development of experimental protocols and individual instrument capabilities and limitations.

  1. Development of Enantiospecific Coupling of Secondary and Tertiary Boronic Esters with Aromatic Compounds.

    Science.gov (United States)

    Odachowski, Marcin; Bonet, Amadeu; Essafi, Stephanie; Conti-Ramsden, Philip; Harvey, Jeremy N; Leonori, Daniele; Aggarwal, Varinder K

    2016-08-01

    The stereospecific cross-coupling of secondary boronic esters with sp(2) electrophiles (Suzuki-Miyaura reaction) is a long-standing problem in synthesis, but progress has been achieved in specific cases using palladium catalysis. However, related couplings with tertiary boronic esters are not currently achievable. To address this general problem, we have focused on an alternative method exploiting the reactivity of a boronate complex formed between an aryl lithium and a boronic ester. We reasoned that subsequent addition of an oxidant or an electrophile would remove an electron from the aromatic ring or react in a Friedel-Crafts-type manner, respectively, generating a cationic species, which would trigger 1,2-migration of the boron substituent, creating the new C-C bond. Elimination (preceded by further oxidation in the former case) would result in rearomatization giving the coupled product stereospecifically. Initial work was examined with 2-furyllithium. Although the oxidants tested were unsuccessful, electrophiles, particularly NBS, enabled the coupling reaction to occur in good yield with a broad range of secondary and tertiary boronic esters, bearing different steric demands and functional groups (esters, azides, nitriles, alcohols, and ethers). The reaction also worked well with other electron-rich heteroaromatics and 6-membered ring aromatics provided they had donor groups in the meta position. Conditions were also found under which the B(pin)- moiety could be retained in the product, ortho to the boron substituent. This protocol, which created a new C(sp(2))-C(sp(3)) and an adjacent C-B bond, was again applicable to a range of secondary and tertiary boronic esters. In all cases, the coupling reaction occurred with complete stereospecificity. Computational studies verified the competing processes involved and were in close agreement with the experimental observations. PMID:27384259

  2. Solvent-induced crystallization of poly(ether ether ketone)

    Science.gov (United States)

    McPeak, Jennifer Lynne

    The purpose of this study was learn how the diffusion, swelling, and crystallization processes are coupled during solvent-induced crystallization of poly(ether ether ketone) (PEEK). Unoriented amorphous PEEK films were immersed in aprotic organic liquids at ambient temperature and bulk properties or characteristics were monitored as a function of immersion time. The sorption behavior, T g and Tm° suppression, crystallinity, and dynamic mechanical response were correlated as a function of solvent chemistry and immersion time. The saturation time of methylene chloride, 1,3-dichloropropane, tetrahydrofuran, cyclopentanone, chlorobenzene, toluene, diethyl ketone, and ethylbenzene in amorphous PEEK films were found to range from hours to days depending on the level of polymer-solvent interactions. In-situ isochronal DMA spectra show that the Tg of PEEK was suppressed from 150°C to below ambient temperature such that crystallization was kinetically feasible during ambient immersion. In addition, an increase in viscoelastic dispersion was attributed to the presence of crystallinity. From dynamic mass uptake and wide-angle x-ray diffraction (WAXD) results, it was found that the bulk sorption rate was equal to the bulk crystallization rate for all solvent systems that promoted SINC and PEEK exhibited diffusion-limited crystallization, irrespective of the nature of the transport mechanism. In addition, the solvent-induced crystals exhibit preferred orientation as supported by photographic WAXD. A distinct sorption front, observed with scanning electron microscopy, further supports the scenario of diffusion-controlled crystallization and one-dimensional diffusion. Isothermal DMA spectra for THF, cyclopentanone, and chlorobenzene, indicate that, as the solvent diffuses into the films, the stiffness of the polymer decreases at short times, begins to increase, and then reaches a relatively time-independent value. It was determined that the initial decrease in the storage

  3. Thermoresponsive cellulose ether and its flocculation behavior for organic dye removal.

    Science.gov (United States)

    Tian, Ye; Ju, Benzhi; Zhang, Shufen; Hou, Linan

    2016-01-20

    A thermoresponsive polymer, 2-hydroxy-3-butoxypropyl hydroxyethyl cellulose (HBPEC), was prepared by grafting butyl glycidyl ether (BGE) onto hydroxyethyl cellulose (HEC). The lower critical solution temperature (LCST) and critical flocculation temperature (CFT) of HBPEC were varied by changing the molar substitution (MS) and salt concentrations. Transmission electron microscopy (TEM) images and fluorescence spectroscopy showed that HBPEC can assemble into micelles. Additionally, using Nile Red as a model dye, the performance of HBPEC for the removing Nile Red from aqueous solutions via cloud point extraction procedures was investigated in detail. The encapsulation behavior of dye in the aqueous solution of HBPEC was studied by fluorescence spectroscopy and fluorescence microscope. The experimental results indicated that 99.4% of dye was removed from the aqueous solutions, and the HBPEC was recycled and reused easily, Furthermore, the recycle efficiency (RE) and maximum loading capacity portrayed little loss with the number of cycles. PMID:26572464

  4. Enantiospecific Alkynylation of Alkylboronic Esters

    OpenAIRE

    Wang, Yahui; Noble, Adam; Myers, Eddie L.; Aggarwal, Varinder K.

    2016-01-01

    Enantioenriched secondary and tertiary alkyl pinacolboronic esters undergo enantiospecific deborylative alkynylation through a Zweifel-type alkenylation followed by a 1,2-elimination reaction. The process involves the use of α-lithio vinyl bromide or vinyl carbamate, species whose application to Zweifel-type reactions has not previously been explored. The resulting functionalized 1,1-disubstituted alkenes undergo facile base-mediated elimination to generate the terminal alkyne products in hig...

  5. Methods of making alkyl esters

    Science.gov (United States)

    Elliott, Brian

    2010-08-03

    A method comprising contacting an alcohol, a feed comprising one or more glycerides and equal to or greater than 2 wt % of one or more free fatty acids, and a solid acid catalyst, a nanostructured polymer catalyst, or a sulfated zirconia catalyst in one or more reactors, and recovering from the one or more reactors an effluent comprising equal to or greater than about 75 wt % alkyl ester and equal to or less than about 5 wt % glyceride.

  6. Sesquiterpene Esters from Salvia roborowskii

    Institute of Scientific and Technical Information of China (English)

    Ya LI; Ning LOU; Yan Qi WU; Xian Feng LIN; Yu LI

    2003-01-01

    Two new sesquiterpene esters, 3β, 6β, 8α-triacetyl-4β, 5α-epoxy -1- oxogermacr-10(14)-ene (1) and 3β, 6β, 8α-triacetyl-4β, 5α-epoxygermacr-1(10)-ene (2) were isolated from the whole plant of Salvia roborowskii Maxim. Their structures were elucidated by means of spectral data (2DNMR and HRMS).

  7. Didymin reverses phthalate ester-associated breast cancer aggravation in the breast cancer tumor microenvironment

    Science.gov (United States)

    HSU, YA-LING; HSIEH, CHIA-JUNG; TSAI, EING-MEI; HUNG, JEN-YU; CHANG, WEI-AN; HOU, MING-FENG; KUO, PO-LIN

    2016-01-01

    The present study demonstrated two novel findings. To the best of our knowledge, it is the first study to demonstrate that regulated upon activation, normal T-cell expressed and secreted (RANTES), produced by breast tumor-associated monocyte-derived dendritic cells (TADCs) following breast cancer cell exposure to phthalate esters, may contribute to the progression of cancer via enhancement of cancer cell proliferation, migration and invasion. Furthermore, the present study revealed that didymin, a dietary flavonoid glycoside present in citrus fruits, was able to reverse phthalate ester-mediated breast cancer aggravation. MDA-MB-231 cells were treated with butyl benzyl phthalate (BBP), di-n-butyl phthalate (DBP) or di-2-ethylhexyl phthalate (DEHP). Subsequently, the conditioned medium (CM) was harvested and cultured with monocyte-derived dendritic cells (mdDCs). Cultures of MDA-MB-231 cells with the conditioned medium of BBP-, DBP- or DEHP-MDA-MB-231 tumor-associated mdDCs (BBP-, DBP- or DEHP-MDA-TADC-CM) demonstrated enhanced proliferation, migration and invasion. Exposure of the MDA-MB-231 cells to DBP induced the MDA-TADCs to produce the inflammatory cytokine RANTES, which subsequently induced MDA-MB-231 cell proliferation, migration and invasion. Depleting RANTES reversed the effects of DBP-MDA-TADC-mediated MDA-MB-231 cell proliferation, migration and invasion. In addition, didymin was observed to suppress phthalate-mediated breast cancer cell proliferation, migration and invasion. The present study suggested that didymin was capable of preventing phthalate ester-associated cancer aggravation. PMID:26893687

  8. Evaluation of Glycol Ether as an Alternative to Perchloroethylene in Dry Cleaning

    Directory of Open Access Journals (Sweden)

    Nikou Hesari

    2014-04-01

    Full Text Available Perchloroethylene (PCE is a highly utilized solvent in the dry cleaning industry because of its cleaning effectiveness and relatively low cost to consumers. According to the 2006 U.S. Census, approximately 28,000 dry cleaning operations used PCE as their principal cleaning agent. Widespread use of PCE is problematic because of its adverse impacts on human health and environmental quality. As PCE use is curtailed, effective alternatives must be analyzed for their toxicity and impacts to human health and the environment. Potential alternatives to PCE in dry cleaning include dipropylene glycol n-butyl ether (DPnB and dipropylene glycol tert-butyl ether (DPtB, both promising to pose a relatively smaller risk. To evaluate these two alternatives to PCE, we established and scored performance criteria, including chemical toxicity, employee and customer exposure levels, impacts on the general population, costs of each system, and cleaning efficacy. The scores received for PCE were 5, 5, 3, 5, 3, and 3, respectively, and DPnB and DPtB scored 3, 1, 2, 2, 4, and 4, respectively. An aggregate sum of the performance criteria yielded a favorably low score of “16” for both DPnB and DPtB compared to “24” for PCE. We conclude that DPnB and DPtB are preferable dry cleaning agents, exhibiting reduced human toxicity and a lesser adverse impact on human health and the environment compared to PCE, with comparable capital investments, and moderately higher annual operating costs.

  9. Activity relationships for aromatic crown ethers

    CERN Document Server

    Wilson, M J

    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...

  10. Results of the L5178Y mouse lymphoma assay and the Balb/3t3 cell in vitro transformation assay for eight phthalate esters.

    Science.gov (United States)

    Barber, E D; Cifone, M; Rundell, J; Przygoda, R; Astill, B D; Moran, E; Mulholland, A; Robinson, E; Schneider, B

    2000-01-01

    Eight phthalate esters, with alcohol chain lengths of 1-11 carbon atoms and with various degrees of branching, were tested in vitro in the L5178Y mouse lymphoma mammalian cell mutation assay and in the Balb/3T3 cell transformation assay. The tests were performed as part of a voluntary testing agreement between the Chemical Manufacturers Association's Phthalate Esters Panel and the United States Environmental Protection Agency (US EPA). The esters tested were: dimethyl phthalate (DMP), di-n-butyl phthalate (DBP), butyl benzyl phthalate (BBP), di-¿n-hexyl, n-octyl, n-decyl¿ phthalate (610P), di-isononyl phthalate (DINP), di-¿heptyl, nonyl, undecyl¿ phthalate (711P), di-isodecyl phthalate (DIDP) and di-undecyl phthalate (DUP). Both DMP and DBP were found to produce significant increases in the mutant frequency in the mouse lymphoma assay in the presence but not in the absence of an Aroclor-induced rat liver activation system (S-9). Ester 610P gave equivocal results in the mouse lymphoma assay in the presence and absence of rat liver S-9. There was no indication of mutagenic potential for any of the other test materials in the mouse lymphoma assay, and none of the test materials increased transformation frequency in the Balb/3T3 cell transformation assay. Aldehyde metabolites of the de-esterified alcohols are postulated to play a role in the positive results for DMP and DBP. PMID:10641018

  11. 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 in...

  12. Bulk and interfacial properties of cellulose ethers

    OpenAIRE

    Bodvik, Rasmus

    2012-01-01

    This work summarizes several studies that all concern cellulose ethers of the types methylcellulose (MC) hydroxypropylmethylcellulose (HPMC) and ethyl(hydroxyethyl)cellulose (EHEC). They share the feature of negative temperature response, as they are soluble in water at room temperature but phase separate and sometimes form gels at high temperatures. The different types of viscosity transitions occurring in these three cellulose ethers are well-known. However, earlier studies have not solved ...

  13. 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.

  14. Impact of ester promoieties on transdermal delivery of ketorolac.

    Science.gov (United States)

    Liu, Kuo-Sheng; Hsieh, Pei-Wen; Aljuffali, Ibrahim A; Lin, Yin-Ku; Chang, Shu-Hao; Wang, Jhi-Joung; Fang, Jia-You

    2014-03-01

    Different types of ketorolac ester prodrugs incorporating tert-butyl (KT), benzyl (KB), heptyl (KH), and diketorolac heptyl (DKH) promoieties were synthesized for the comparison of percutaneous penetration. The prodrugs were characterized according to their melting point, capacity factor, lipophilicity, solubility in 30% ethanol/buffer, enzymatic hydrolysis, in vitro skin permeation, hair follicle accumulation, and in vivo skin tolerance. Interactions between the prodrugs and esterases were predicted by molecular docking. Both equimolar suspensions and saturated solutions in 30% ethanol/pH 7.4 buffer were employed as the applied dose. All of the prodrugs exhibited a lower melting point than ketorolac. The lipophilicity increased in the following order: ketorolac absorption into follicles and a threefold greater follicular uptake compared with ketorolac. KB, KH, and DKH slightly but significantly increased transepidermal water loss (TEWL) after consecutive administration for 7 days, whereas ketorolac and KT exhibited no influence on TEWL. According to the experimental results, it can be concluded that an optimal balance between lipophilicity and aqueous solubility is important in the design of a successful prodrug. The acceptable skin tolerance for safe application is also an important consideration. PMID:24481782

  15. Biochemical characterization of a first fungal esterase from Rhizomucor miehei showing high efficiency of ester synthesis.

    Directory of Open Access Journals (Sweden)

    Yu Liu

    Full Text Available BACKGROUND: Esterases with excellent merits suitable for commercial use in ester production field are still insufficient. The aim of this research is to advance our understanding by seeking for more unusual esterases and revealing their characterizations for ester synthesis. METHODOLOGY/PRINCIPAL FINDINGS: A novel esterase-encoding gene from Rhizomucor miehei (RmEstA was cloned and expressed in Escherichia coli. Sequence analysis revealed a 975-bp ORF encoding a 324-amino-acid polypeptide belonging to the hormone-sensitive lipase (HSL family IV and showing highest similarity (44% to the Paenibacillus mucilaginosus esterase/lipase. Recombinant RmEstA was purified to homogeneity: it was 34 kDa by SDS-PAGE and showed optimal pH and temperature of 6.5 and 45°C, respectively. The enzyme was stable to 50°C, under a broad pH range (5.0-10.6. RmEstA exhibited broad substrate specificity toward p-nitrophenol esters and short-acyl-chain triglycerols, with highest activities (1,480 U mg(-1 and 228 U mg(-1 for p-nitrophenyl hexanoate and tributyrin, respectively. RmEstA efficiently synthesized butyl butyrate (92% conversion yield when immobilized on AOT-based organogel. CONCLUSION: RmEstA has great potential for industrial applications. RmEstA is the first reported esterase from Rhizomucor miehei.

  16. Damping properties and morphology of polyurethane/vinyl ester resin interpenetrating polymer network

    International Nuclear Information System (INIS)

    A series of polyurethane/vinyl ester resin simultaneous and gradient interpenetrating polymer networks (PU/VER IPN and gradient IPN), cured at room temperature, were synthesized by introducing acrylic esters as VER's comonomers. The effects of thermodynamic factor, kinetic factor, component ratio and gradient techniques on their damping properties were studied by DMA. It was found that the damping properties of general PU/VER (St) IPN with styrene (St) as VER's comonomer are improved by introducing acrylic esters instead of St. When the relative polymerization rates of the networks are close, 80:20, 70:30 and 60:40 PU/VER (BMA) IPNs with butyl methacrylate (BMA) as VER's comonomer have excellent damping properties. The gradient IPN with better damping properties than simultaneous IPNs was obtained by adjusting the gradient techniques. The tan δ values of the gradient IPN with the time interval of 3 h and the component ratios of 50:50-60:40-70:30 are higher than 0.3 from -57 deg. C to higher than 90 deg. C, and its tan δ values are higher than 0.5 from -36 to 54 deg. C. The results of EDX revealed that the gradient structure is formed in transition regions of gradient IPN. The results detected by TEM and AFM showed that the phase ranges of PU/VER (BMA) IPNs and gradient IPN obtained are both in nanometer scale. Furthermore, the relationship of microstructure and damping properties was studied

  17. Ester Tuiksoo. Proua Suhkru kibedad päevad / Ester Tuiksoo ; interv. Piret Tali

    Index Scriptorium Estoniae

    Tuiksoo, Ester, 1965-

    2005-01-01

    Põllumajandusminister Ester Tuiksoo, kellel peagi täitub ministri ametis aasta Euroopa Liidu suhkrutrahvist, maaettevõtlusest, põllumajandusest, Euroopa Liidu toetustest, ministri elu- ja teenistuskäigust. Lisa: Ester Tuiksoo

  18. Biodegradation of Di-n-Butyl Phthalate by a Newly Isolated Halotolerant Sphingobium sp.

    Directory of Open Access Journals (Sweden)

    Decai Jin

    2013-12-01

    Full Text Available A Gram-negative strain (TJ capable of growing aerobically on mixed phthalate esters (PAEs as the sole carbon and energy source was isolated from the Haihe estuary, Tianjin, China. It was identified as belonging to the Sphingobium genus on the basis of morphological and physiological characteristics and 16S rRNA and gyrb gene sequencing. The batch tests for biodegradation of di-n-butyl phthalate (DBP by the Sphingobium sp. TJ showed that the optimum conditions were 30 °C, pH 7.0, and the absence of NaCl. Stain TJ could tolerate up to 4% NaCl in minimal salt medium supplemented with DBP, although the DBP degradation rates slowed as NaCl concentration increased. In addition, substrate tests showed that strain TJ could utilize shorter side-chained PAEs, such as dimethyl phthalate and diethyl phthalate, but could not metabolize long-chained PAEs, such as di-n-octyl phthalate, diisooctyl phthalate, and di-(2-ethyl-hexyl phthalate. To our knowledge, this is the first report on the biodegradation characteristics of DBP by a member of the Sphingobium genus.

  19. Effects of di-n-butyl phthalate on the physiology and ultrastructure of cucumber seedling roots.

    Science.gov (United States)

    Zhang, Ying; Tao, Yue; Sun, Guoqiang; Wang, Lei

    2014-05-01

    Agricultural pollution caused by the use of plastic sheetings has been documented to be a widespread problem in most of the major crop-planting regions of the world. In order to better understand the phytotoxic mechanisms induced by phthalic acid esters involved with this problem, Cucumber sativus L. cv Jinyan No. 4 were sown in pots to the three-leaf-stage in the presence of di-n-butyl phthalate (DBP; 0, 30, 50, 100, and 200 mg L(-1)) for 1, 3, 5, or 7 days. Physiology, biochemistry, and ultrastructure of seedling roots were examined. The results indicated that activities of three antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD)) were stimulated at low-DBP treatments and decreased under higher levels (>100 mg L(-1)) compared to the controls. On the other hand, SOD and POD provided a better defense against DBP-induced oxidative damage in the roots of cucumber seeding, compared to CAT. The productions of both malondialdehyde (MDA) and proline (Pro) were promoted under DBP stress. Visible impact on the cytoderm, mitochondrion, and vacuole was detected, possibly as a consequence of free radical generation. These results suggested that activation of the antioxidant system by DBP led to the formation of reactive oxygen species that resulted in cellular damage. PMID:24573460

  20. Effect of benzyl butyl phthalate on physiology and proteome characterization of water celery (Ipomoea aquatica Forsk.).

    Science.gov (United States)

    Chen, Wen-Ching; Huang, Han-Ching; Wang, Yei-Shung; Yen, Jui-Hung

    2011-07-01

    This study examined the effect of benzyl butyl phthalate (BBP), a phthalate ester (PAE) and an endocrine disruptor, on water celery, Ipomoea aquatica Forsk., one of the most popular leaf vegetables in Taiwan. After 28 days of cultivation, treatment with 100 mgL⁻¹ BBP retarded plant growth and decreased biomass and number of mature leaves and caused the accumulation of proline in leaves of water celery, but the concentrations of chlorophyll a and b in the leaves remained constant. 2-D gel electrophoresis and matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of the proteome of leaf tissue revealed five protein spots with up- and down-regulated expression. The predicted protein XP_001417439 was down-regulated, which explained inhibition of plant growth, and the proteina XP_001417040, calreticulin, GAI-like protein 1, and (-)-linalool synthase were up-regulated, which indicates interference with the cell cycle and protein synthesis, as well as dwarfism of water celery. BBP is a stressor on the growth of water celery, and proteome analysis revealed the up- and down-regulation of genes involved in plant growth with BBP treatment. PMID:21496923

  1. ESR investigation of ester π-cation radicals in a freon matrix at low temperatures: evidence for unusual barriers to methyl group rotation and intramolecular bonding

    International Nuclear Information System (INIS)

    γ-Irradiation of dilute solutions of a number of esters in CFCl3 at 77 K is shown by ESR spectroscopy to produce the π-cation radicals of these molecules. The π-cations formed are those of the methyl and ethyl formates, acetates, and propionates. Larger esters containing propyl and butyl side chains are suggested to be unstable toward deprotonation at 77 K. Synthesis of deuterium-labeled compounds was employed to assign proton hyperfine couplings to specific sites in the π-cation radicals. The π-cations of the ethyl esters show unusually large couplings to the terminal methyl groups. In addition, large barriers to methyl group rotation are found for both the methyl and ethyl ester cation radicals. The large barriers suggest intermolecular bonding between the alkyl group and the carbonyl oxygen in the ester functional group. Such a hypothesis is supported by the finding of a torsional motion in the terminal methyl group of ethyl formate π-cation which has a ca. 1.7 kcal/mol activation energy barrier. It is suggested that a new intramolecular π*-bond is responsible for the formation of cyclic rings in the methyl- and ethyl-substituted ester cation radicals

  2. Conversion of Lignocellulosic Biomass to Ethanol and Butyl Acrylate

    Energy Technology Data Exchange (ETDEWEB)

    Binder, Thomas [Archer Daniels Midland Company, Decatur, IL (United States); Erpelding, Michael [Archer Daniels Midland Company, Decatur, IL (United States); Schmid, Josef [Archer Daniels Midland Company, Decatur, IL (United States); Chin, Andrew [Archer Daniels Midland Company, Decatur, IL (United States); Sammons, Rhea [Archer Daniels Midland Company, Decatur, IL (United States); Rockafellow, Erin [Archer Daniels Midland Company, Decatur, IL (United States)

    2015-04-10

    Conversion of Lignocellulosic Biomass to Ethanol and Butyl Acrylate. The purpose of Archer Daniels Midlands Integrated Biorefinery (IBR) was to demonstrate a modified acetosolv process on corn stover. It would show the fractionation of crop residue to distinct fractions of cellulose, hemicellulose, and lignin. The cellulose and hemicellulose fractions would be further converted to ethanol as the primary product and a fraction of the sugars would be catalytically converted to acrylic acid, with butyl acrylate the final product. These primary steps have been demonstrated.

  3. Thin sulfonated poly(ether ether ketone) films for the dehydration of compressed carbon dioxide

    NARCIS (Netherlands)

    Koziara, B.T.

    2015-01-01

    In this thesis, the properties of thin films from highly sulfonated poly(ether ether ketone) (SPEEK) have been investigated within the context of their application as membranes for the dehydration of compressed carbon dioxide. Spectroscopic ellipsometry has been used as the predominant measurement t

  4. Carboxylic Acid Esters as Substrates of Cholinesterases

    Science.gov (United States)

    Brestkin, A. P.; Rozengart, E. V.; Abduvakhabov, A. A.; Sadykov, A. A.

    1983-10-01

    Data on the kinetics of the hydrolysis of various carboxylic acid esters by two main types of cholinesterases — acetylcholinesterase from human erythrocytes and butyrylcholinesterase from horse blood serum — are surveyed. It is shown that the rate of enzyme hydrolysis depends significantly on the structure of the acyl part of the ester molecule, the nature of the ester heteroatom, the structure of the alcohol component, and particularly the structure of the onium group. Esters based on natural products are of special interest as specific substrates of these enzymes. The role of the productive and non-productive sorption of the substrates in enzyme catalysis is demonstrated. The bibliography includes 81 references.

  5. Hydrogen bonding in the recovery of phenols and methyl-t-butyl ether : molecular modeling and calorimetry

    NARCIS (Netherlands)

    Cuypers, R.

    2010-01-01

    The purification of waste water is very important, for clean potable water is a common good and a necessity. Surface water purification is nowadays carried out on a massive industrial scale, and clean water is at our disposal virtually everywhere and always. However, cleaning industrial waste water

  6. Hydrogen bonding in the recovery of phenols and methyl-t-butyl ether : molecular modeling and calorimetry

    OpenAIRE

    Cuypers, R.

    2010-01-01

    The purification of waste water is very important, for clean potable water is a common good and a necessity. Surface water purification is nowadays carried out on a massive industrial scale, and clean water is at our disposal virtually everywhere and always. However, cleaning industrial waste water can be a difficult task. Although apolar and slightly polar compounds can be removed from water relatively easily e.g. by extraction to an apolar phase, more polar pollutants like phenol and methyl...

  7. UV absorption spectra and kinetics for alkyl and alkyl peroxy radicals originating from di-tert-butyl ether

    DEFF Research Database (Denmark)

    Nielsen, O.J.; Sehested, J.; Langer, S.;

    1995-01-01

    (CH3)(3)COC(CH3)(2)CH2O2 radicals were found to be (2.9 +/- 0.2) X 10(-11) cm(3) molecule(-1) s(-1) and (2.7 +/- 0.2) X 10(-12) cm(3) molecule(-1) s(-1), respectively. For the reaction of the alkyl radical with O-2 in 1 atm pressure of SF6 a rate constant of (7.2 +/- 1.1) X 10(-13) cm(3) molecule(-1...

  8. Para-ter-butyl of calix(4)arene with acetamide-ether as inorganic-organic receiver

    International Nuclear Information System (INIS)

    A new functionalized calix(4)arene was designed and constructed with predetrmined properties to form lanthanides complexes and to sensibilize its luminescent properties. This, in addition to sensibilize that photophysical property and once formed the complex resulted a good receiver of organic molecules as it is demonstrated the crystal structure of the lutetium complex. (Author)

  9. Preparation and characterization of Pd doped ceria–ZnO nanocomposite catalyst for methyl tert-butyl ether (MTBE) photodegradation

    Energy Technology Data Exchange (ETDEWEB)

    Seddigi, Zaki S. [Chemistry Department, Umm Al-Qura University, Makkah (Saudi Arabia); Bumajdad, Ali [Chemistry Department, Faculty of Science, Kuwait University (Kuwait); Ansari, Shahid P. [Chemistry Department, Umm Al-Qura University, Makkah (Saudi Arabia); Ahmed, Saleh A., E-mail: saleh_63@hotmail.com [Chemistry Department, Umm Al-Qura University, Makkah (Saudi Arabia); Danish, Ekram Y. [Chemistry Department, King Abdulaziz University, Jeddah (Saudi Arabia); Yarkandi, Naeema H. [Chemistry Department, Umm Al-Qura University, Makkah (Saudi Arabia); Ahmed, Shakeel [Center for Refining and Petrochemicals, Research Institute, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)

    2014-01-15

    Highlights: • Novel Pd supported ceria–ZnO photocatalysts were prepared with different amounts of palladium. • The photocatalytic activity of these catalysts was evaluated for degradation of MTBE in water. • Near complete removal of MTBE was achieved using 1% Pd doped ceria–ZnO catalyst and UV irradiation. • Highest rate constant was obtained in case of 1% Pd doped ceria–ZnO catalyst. • Shape and size of pores are important factors for high photoactivity of catalyst. -- Abstract: A series of binary oxide catalysts (ceria–ZnO) were prepared and doped with different amounts of palladium in the range of 0.5%–1.5%. The prepared catalysts were characterized by SEM, TEM, XRD and XPS, as well as by N{sub 2} sorptiometry study. The XPS results confirmed the structure of the Pd CeO{sub 2−x}-ZnO. The photocatalytic activity of these catalysts was evaluated for degradation of MTBE in water. These photocatalyst efficiently degrade a 100 ppm aqueous solution of MTBE upon UV irradiation for 5 h in the presence of 100 mg of each of these photocatalysts. The removal of 99.6% of the MTBE was achieved with the ceria–ZnO catalyst doped with 1% Pd. In addition to the Pd loading, the N{sub 2} sorptiometry study introduced other factors that might affect the catalytic efficiency is the catalyst average pore sizes. The photoreaction was determined to be a first order reaction.

  10. Intramolecular fixation of t-butyl groups in thiolactim ethers influencing molecular conformation and the packing behavior

    Science.gov (United States)

    Hübscher, Jörg; Gruber, Thomas; Seichter, Wilhelm; Kortus, Jens; Weber, Edwin

    2015-07-01

    Derived from the result of a previous crystallographic study regarding an ethynylene bridged bispyrimidine, the presence of two intramolecular C-H⋯N hydrogen bonding contacts being responsible for a fixation of the terminal t-butylthio units to the azine nitrogens was noticed. Acting as stimulus, a series of different pyridine and pyridazine derivatives also featuring this unusual functionality has been synthesized and structurally studied. In order to support the investigations concerning this particular bonding pattern performed via X-ray structure analysis, calculations based on the density functional theory were carried out. It was found that the formation of the intramolecular hydrogen bonding motif has not only impact on the molecular stability but in some cases also predictably influences the reactivity and the packing behavior of the different heterocycles.

  11. AN EXPERIMENTAL STUDY OF PHYTOREMEDIATION OF METHYL-TERT-BUTYL-ETHER (MTBE) IN GROUNDWATER. (R825549C062)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  12. ADVANCED OXIDATION PROCESSES (AOPS) FOR DESTRUCTION OF METHYL TERTIARY BUTYL ETHER (MTBE -AN UNREGULATED CONTAMINANT) IN DRINKING WATER

    Science.gov (United States)

    Advanced oxidation processes (AOPs) provide a promising treatment option for the destruction of MTBE directly in surface and ground waters. An ongoing study is evaluating the ability of three AOPs; hydrogen peroxide/ozone (H2O2/ O3), ultraviolet irradiation/ozone (UV/O3) and ultr...

  13. Photoinitiated polymerization of new hybrid monomer containing vinyl ether and (methyl) acryloyl groups

    Science.gov (United States)

    Diao, Cuimei; Zou, Yingquan

    2011-04-01

    The photopolymerization kinetics of 4-(vinyloxy)butyl methacrylate containing cationic and free radical polymerizable vinyl groups was studied by real-time Fourier transform infrared spectra (RT-FTIR) .The cationic polymerizable vinyl ether moieties(Vc) of the hybrid monomer in solution polymerized rapidly by exposure to UV light in presence of a cationic photoinitiator such as an iodonium salt or suflonium salt .High conversions, of 90%, were obtained for most of the systems investigated. The efficiency of the cationic photoinitiators in initiating the polymerization of the vinyl ether moieties (Vc) of the hybrid monomer was in the order: suflonium salt > iodonium salt . The free radical polymerizable methacrylate groups (Vr) of the hybrid monomer in solution polymerized by exposure to UV light in presence of a radical photoinitiator such as 2,4,6-trimethyl benzoyl diphenylphoshine oxide (TPO), 2-isopropyl thioxanthone (ITX) , Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (Irgaure 819), 2-Methyl-4'-(methylthio)-2-morpholinopropiophenone (Irgaure 907). Among the photoinitiators , the best effect in initiating the polymerization of methacrylate groups (Vr) of the hybrid monomer is initiator Irgaure 907.

  14. Synthesis of Aryl Allyl Ether in the Recyclable Ionic Liquid [bmim]PF6

    Institute of Scientific and Technical Information of China (English)

    Zhou Mei-Yun; Li Yi-Qun; Xu Xin-Ming

    2004-01-01

    Ionic liquids, especially imidazonium salts, have recently gained recognition as possible environmentally benign alternative chemical process solvents. This is mainly due to their nonvolatile nature, insolubility in some solvents as well as their ability to dissolve a wide range of organic and inorganic materials, allowing the ionic liquids easy recovery and recycling. Examples of their application in organic reactions have been summarized in a number of recent review articles.1Aryl allyl ether is very useful intermediate in organic synthesis. The Williamson reaction is a well knows method for the preparation ethers. However, the reaction of alkylating agents with the phenoxide ions was conventionally carried out in the organic solvents. The usual solvents for this type of reaction are DCM, 2 DMSO, 3 DMF, 4 CH3CN5 etc. With the current desire to avoid the use of organic molecular solvents in organic synthesis, we decide to investigate the use of the ionic liquid for the alternative solvent for the Williamson reaction to prepare the aryl allyl ethers. The ionic liquid employed here was the moisture stable 1-butyl-3-methylimidazolium hexafluorophosphate [bmim]PF6.6 The ionic liquid is non-volatile, thermally stable, and depending on the anion, can present low immiscible with water,alkanes and dialky ethers. We have now found that aryl allyl ethers can have been obtained from various phenols and allyl bromide in the presence of potassium hydroxide in [bmim]PF6 as a replacement for classical organic solvents in the ambient temperature. The results are shown in Scheme 1.The reaction were carried out by simple mixing the phenolwith the ally bromide and potassium hydroxide in [bmim]PF6 and stirred at room temperature for 4h. The results are summarized in Table 1.In conclusion, Williamson reaction can be successfully conducted in ionic liquid [bmim]PF6 with a number of advantages: the procedure is simple, the reaction condition is mild and the yields are excellent

  15. Thermoresponsive and bioactive poly(vinyl ether)-based hydrogels synthesized by radiation copolymerization and photochemical immobilization

    International Nuclear Information System (INIS)

    A thermoresponsive hydrogel was synthesized by radiation copolymerization of ethylene glycol vinyl ether (EGVE) and butyl vinyl ether (BVE) in the presence of cross-linking agent diethylene glycol divinyl ether. The gel was modified by a cell adhesion factor RGD by photochemical immobilization technique. While the unmodified hydrogel shows fully hydrated form at low temperatures (+4 oC) and it extensively dehydrates at 37 oC, the biomodified hydrogel still kept its thermoresponsive character after immobilization. The effectiveness of immobilization was checked with FTIR-ATR and XPS. The use of bioactive thermoresponsive hydrogels in cell culture applications was investigated. For this purpose, cell culture experiments were realized by L929 mouse fibroblasts. Cell attachment experiments revealed the effect of immobilized RGD with higher values of cell attachment (∼85%), which were obtained especially in the absence of serum. The thermoresponsive character of the hydrogel was useful for the application of low-temperature treatment in order to recover the attached viable cells from the surface of the hydrogel without using trypsin. When the culture temperature was decreased from 37 to 10 deg. C for 30 min ∼80% of the cells were detached from the hydrogel surface

  16. Vinyl ether/acrylic acid terpolymer hydrogels synthesized by γ-radiation: characterization, thermosensitivity and pH-sensitivity

    International Nuclear Information System (INIS)

    The radiation copolymerization of hydrophilic ethylene glycol vinyl ether (EGVE), hydrophobic butyl vinyl ether (BVE) and/or acidic comonomer acrylic acid (AA) was realized in the presence of crosslinking agent diethylene glycol divinyl ether (DEGDVE). The swelling studies which were carried out at 4 and 37 deg. C in phosphate buffer solution (PBS, pH 7.4) showed that equilibrium swelling ratios of the hydrogels (except EGVE homopolymer hydrogel) decreases with increasing temperature and swelling process obeys non-Fickian diffusion mechanism. The pH-dependent swelling behaviour of the hydrogels was examined in buffered solutions at various pHs. The swelling process is reversible and pH-dependent for the AA-containing hydrogel. While this hydrogel shows a fully hydrated form at pH>6; it extensively dehydrates below pH 6. The gels are stable after the repeated swelling experiments. The molecular structure of the hydrogels was studied by Fourier Transform Infrared Spectroscopy and their thermal behaviour was investigated by Differential Scanning Calorimetry and Thermal Gravimetric Analysis. The surface and cross-section structures of the gels were examined by a Scanning Electron Microscope

  17. Synthesis of insecticidal sucrose esters

    Institute of Scientific and Technical Information of China (English)

    Song Zi-juan; Li Shu-jun; Chen Xi; Liu Li-mei; Song Zhan-qian

    2006-01-01

    Some synthetic sucrose esters (SE) are a relatively new class of insecticidal compounds produced by reacting sugars with fatty acids, which are safe for the environment. Especially, sucrose esters composed of C6-C12 fatty acids have desirable insecticidal properties against many soft-bodied arthropod pests. In our study, sucrose octanoate which has the highest activity against a range of arthropod species was synthesized by a trans-esterification method and proved its insecticidal property. Under the condition of a homogeneous liquid, sucrose octanoate was prepared by reacting ethyl octanoate with sucrose at reduced pressure; the yield was 79.11%. Sucrose octanoate synthesized was identified and its property analyzed by IR, TLC and spectrophotometric analysis. It was shown that the ratio of monoester to polyester in sucrose octanoate was 1.48:1. The insecticidal activity of the synthetic sucrose octanoate was evaluated at a concentration of 4 and 8 mg·mL-1. The mortality of first-instar larvae ofLymantria dispar from its contact toxicity was 72.5% after 36 hours, the revision insect reduced rate of Aphis glycines reached above 80% at 4 and 8 mg·mL-1 after being treated for 5 days. Since the SE products are nontoxic to humans and higher animals, fully biodegradable and hydrolyzed to readily metabolizable sucrose and fatty acid, they are not harmful to crops and appear to be good insecticide candidates.

  18. 76 FR 59906 - Fluazifop-P-butyl; Pesticide Tolerances

    Science.gov (United States)

    2011-09-28

    ... Performance Liquid Chromatography/Ultra-Violet Spectrometry (HPLC/UV)) is available to enforce the tolerance... of fluazifop-P-butyl in or on cotton, gin byproducts; cotton, refined oil; and cotton, undelinted... Tolerance In the Federal Register of December 15, 2010 (75 FR 78240) (FRL- 8853-1), EPA issued a...

  19. 27 CFR 21.100 - n-Butyl alcohol.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false n-Butyl alcohol. 21.100 Section 21.100 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants §...

  20. 27 CFR 21.101 - tert-Butyl alcohol.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false tert-Butyl alcohol. 21.101 Section 21.101 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants §...

  1. A Study of the Teratogenicity of Butylated Hydroxyanisole on Rabbits

    DEFF Research Database (Denmark)

    Hansen, Ernst; Meyer, Otto A.

    1978-01-01

    A teratogenicity study on butylated hydroxyanisole (BHA) was carried out in SPF New Zealand White rabbits. BHA was given by gavage from day 7–18 of the gestation period in doses of 0, 50, 200 and 400 mg/kg body wt./day. The fetuses were removed on day 28. No effect related to the treatment with BHA...

  2. Soil contamination by phthalate esters in Chinese intensive vegetable production systems with different modes of use of plastic film

    International Nuclear Information System (INIS)

    The concentrations of six priority phthalic acid esters (PAEs) in intensively managed suburban vegetable soils in Nanjing, east China, were analyzed using gas chromatography–mass spectrometry (GC–MS). The total PAE concentrations in the soils ranged widely from 0.15 to 9.68 mg kg−1 with a median value of 1.70 mg kg−1, and di-n-butyl phthalate (DnBP), bis-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP) were the most abundant phthalate esters. Soil PAE concentrations depended on the mode of use of plastic film in which PAEs were incorporated as plasticizing agents and both the plastic film and poultry manure appeared to be important sources of soil PAEs. Vegetables in rotation with flooded rice led to lower concentrations of PAEs in soil. The results indicate that agricultural plastic film can be an important source of soil PAE contamination and further research is required to fully elucidate the mechanisms of PAE contamination of intensive agricultural soils with different use modes of use of plastic film. -- Highlights: •Phthalate esters in soils from suburban intensive vegetable production systems were investigated. •Phthalate levels and risks of the vegetable soils with different plastic film use modes were examined. •Sources of phthalate esters in vegetable production soils were analyzed. -- PAE contamination of intensively managed vegetable soils varied widely depending on the mode of use of plastic film in different production systems

  3. 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

  4. A comparison of the effect of intranasal desmopressin and intramuscular hyoscine N-butyl bromide combination with intramuscular hyoscine N-butyl bromide alone in acute renal colic

    OpenAIRE

    Abdol-Reza Kheirollahi; Mohammad Tehrani; Mohammad Bashashati

    2010-01-01

    Background: Patients with acute renal colic usually require immediate diagnosis and treatment. In this clinical trial analgesic effect of hyoscine N-butyl bromide and desmopressin combination in comparison with hyoscine N-butyl bromide alone in patients with acute renal colic induced by urinary stones was assessed. Methods: The study included 114 patients randomly allocated in two groups (A and B). Patients in group A received 20 mg intramuscular hyoscine N-butyl bromide at admission tim...

  5. A Convenient and Efficient Procedure for Oxime Ethers

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Acetophenone oxime and benzaldehyde oxime were converted to oxime ethers in the presence of alkyl halide or methyl sulfate and KOH in aqueous DMSO in 5 to 70 min. The yields of oxime ethers were 70 - 96%.

  6. (R)-N-{2-tert-Butyl-2-[(R)-tert-butyl­sulfonamido]ethylidene}-tert-butane­sulfonamide

    OpenAIRE

    Cong-Bin Fan; Xiao-Xia Sun; Yu Hu

    2008-01-01

    The title compound, C14H30N2O2S2, is the product of the monoaddition reaction of tert-butyl magnesium chloride with bis-[(R)-N-tert-butanesulfinyl]ethanediimine. There are two almost identical molecules in the asymmetric unit, the molecular conformation of which is stabilized by an intramolecular N—H...N hydrogen bond.

  7. Biodegradation of phthalate esters during the mesophilic anaerobic digestion of sludge

    DEFF Research Database (Denmark)

    Gavala, Hariklia N.; Alatriste-Mondragon, Felipe; Iranpour, R.;

    2003-01-01

    Phthalic acid esters (PAE) are commonly found in the sludge generated in the wastewater treatment plants. Anaerobic digestion followed by land application is a common treatment and disposal practice of sludge. To date, many studies exist on the anaerobic biodegradation rates of PAE, especially...... of the easily biodegradable ones, whereas the higher molecular weight PAE have reported to be non-biodegradable under methanogenic conditions. Furthermore, there is no information on the effect of the PAE on the performance of the anaerobic digesters treating sludge. In this study, the anaerobic biodegradation...... of di-n-butyl phthalate (DBP), di-ethyl phthalate (DEP) and di-ethylhexyl phthalate (DEHP) was investigated and their relative rates of anaerobic degradation were calculated. Also, the biological removal of PAE during the anaerobic digestion of sludge in bench-scale digesters was investigated using DBP...

  8. 40 CFR 721.3435 - Butoxy-substituted ether alkane.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Butoxy-substituted ether alkane. 721... Substances § 721.3435 Butoxy-substituted ether alkane. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as butoxy-substituted ether...

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

    International Nuclear Information System (INIS)

    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

  10. Finkelstein Reaction in Functionalized Crown-ether Ionic Liquids

    Institute of Scientific and Technical Information of China (English)

    Xiao Hua WANG; Han Zhi WANG; Hui LIU; Yuan KOU

    2006-01-01

    Functional crown-ether ionic liquids were used as catalytic green solvents of Finkelstein reaction of 1-bromooctane and iodide. The rate and yield of the reaction were obvious improved compared with that using crown ether in water. No free crown ether loss was observed after reaction.

  11. Alkyl Aryl Ether Bond Formation with PhenoFluor**

    OpenAIRE

    Shen, Xiao; Neumann, Constanze N.; Kleinlein, Claudia; Claudia, Nathaniel W.; Ritter, Tobias

    2015-01-01

    An alkyl aryl ether bond formation reaction between phenols and primary and secondary alcohols with PhenoFluor has been developed. The reaction features a broad substrate scope and tolerates many functional groups, and substrates that are challenging for more conventional ether bond forming processes may be coupled. A preliminary mechanistic study indicates reactivity distinct from conventional ether bond formation.

  12. 40 CFR 721.3550 - Dipropylene glycol dimethyl ether.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Dipropylene glycol dimethyl ether. 721... Substances § 721.3550 Dipropylene glycol dimethyl ether. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as dipropylene glycol dimethyl ether (PMN...

  13. 40 CFR 799.4440 - Triethylene glycol monomethyl ether.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Triethylene glycol monomethyl ether... REQUIREMENTS Specific Chemical Test Rules § 799.4440 Triethylene glycol monomethyl ether. (a) Identification of test substance. (1) Triethylene glycol monomethyl ether (TGME, CAS No. 112-35-6) shall be tested...

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

    Science.gov (United States)

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

    2016-07-01

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

  15. Polyimides Containing Carbonyl and Ether Connecting Groups

    Science.gov (United States)

    Hergenrother, Paul M.; Havens, Stephen J.

    1987-01-01

    Semicrystallinity gives rise to tough, solvent-resistant polymers. New polyimides prepared from reaction of aromatic dianhydrides with new diamines containing carbonyl and ether connecting groups between aromatic rings. Damines prepared from reaction of 4-aminophenol with activated aromatic difluoro compounds in presence of potassium carbonate. These types of polymers have potential applications in molded products, films, adhesives, and composites.

  16. POLYBROMINATED DIPHENYL ETHERS IN SOUTHERN MISSISSIPPI CATFISH

    Science.gov (United States)

    Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in a wide variety of consumer products. Concerns surrounding these compounds are primarily due do their ubiquitous presence in the environment as well as in human tissue, such as milk, coupled with evidence indi...

  17. Identification and quantification of n-octyl esters of alkanoic and hexanedioic acids and phthalates as urban wastewater markers in biota and sediments from estuarine areas.

    Science.gov (United States)

    Chaler, Roser; Cantón, Lourdes; Vaquero, Menchu; Grimalt, Joan O

    2004-08-13

    A gas chromatographic method for the identification and quantification of n-octyl esters (from n-octyl tetradecanoate to n-octyl hexa-cosanoate including dioctyl hexanedioate) and phthalates [dibutyl phthalate, benzyl butyl phthalate and di(2-ethylhexyl) phthalate] in sediments and biota from estuarine environments is described. Standards used for identification and quantification of some n-octyl esters were synthesized. The method has allowed the analysis of these compounds in polychaeta (Nereis diversicolor), oysters (Crassostea angulata), crabs (Carcinus maenas) and fish (Chelon labrosus, Platichtys flesus and Chondostroma polylepis) that were collected at different locations of the Urdaibai estuary (Bizkaia, Basque Country, Spain). Total phthalates and n-octyl esters ranged between 0.01 and 12 microg g(-1) and 0.05 and 9.4 microg g(-1), respectively, and were predominantly found in polychaeta and fish. Sediments did not contain these compounds in significant amount, only benzyl butyl phthalate, dioctyl hexanedioate and di(2-ethylhexyl) phthalate were found above limit of detection (0.01-0.05 microg g(-1)). PMID:15387189

  18. Cold Flow Properties of Fatty Esters

    Directory of Open Access Journals (Sweden)

    Andrea Kleinová

    2007-09-01

    Full Text Available The article is devoted to the study of cold fl ow properties of neat esters of branched chain alcohols with fatty acids and blends of these esters with fossil diesel fuel. According to the determined CFPP values, the influence of alcohol branching on the fuel filterability is negligible and was detected only in the case of 2-ethyl hexanol. Fossil fuel blending with fatty esters up to 10 % vol. does not substantially change the cold flow properties of fossil fuel. DSC cooling scan parameters should be employed to predict CFPP of blended diesel fuel.

  19. The effects of pH in profile of lipid and ester accumulation of arthrospira platensis (spirulina) as a potential source of biodiesel

    International Nuclear Information System (INIS)

    This study aimed to produce biodiesel (ester-based fuel) using the extracts of microalgae Arthrospira platensis (Spirulina). Specifically, the research focused in determining effect of pH in culturing the Spirulina and its lipid accumulation; determining the constituents present in the lipid extracts; and determining the methyl esters in the transesterified lipids. The best pH condition in culturing the algal sample was found to be at pH 10 to 11. Analysis of the extracted lipid samples revealed that pH condition in culturing medium has a significant effect on the lipid accumulation in Spirulina. Perkin Elmer Claurus 500 GC-MS system elucidated that the constituents present in the experimental samples were esterified lipids. The esters were derived from butanoic, hexadeanoic and octadecanoic acid. About 19 free fatty acids out of 23 determined compounds present were from the controlled sample which suggests that these were main precursors of the esters found in the sample were butyl, allyl nonyl, propyl tetradecyl, methylpropyl, allyl dodecyl, hexyl pentadecyl, dodecyl propyl, heptyl esters with the parent chain of fatty acids enumerated above. These showed that pH manipulations could be used as a direct transesterification of fatty acids in producing biodiesels. (author)

  20. Radiation-induced cationic curing of vinyl ethers

    International Nuclear Information System (INIS)

    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

  1. Endocrine disrupting effects of butylated hydroxyanisole (BHA - E320)

    OpenAIRE

    POP, ANCA; KISS, BELA; Felicia LOGHIN

    2013-01-01

    Butylated hydroxyanisole (BHA) is extensively used as antioxidant in foods, food packaging, cosmetics and pharmaceuticals. In the past years, it raised concerns regarding its possible endocrine disrupting effect. The existing in vitro studies indicate that BHA presents a weak estrogenic effect and also anti-androgenic properties while an in vivo study found it to have antiestrogenic properties. There is no sufficient data available at the moment to draw a conclusion regarding the safety of BH...

  2. Endocrine Disrupting Effects Of Butylated Hydroxyanisole (Bhabhabha - E320)

    OpenAIRE

    Anca Pop; Bela Kiss; Felicia Loghin

    2014-01-01

        Butylated hydroxyanisole (BHA) is extensively used as antioxidant in foods, food packaging, cosmetics and pharmaceuticals. In the past years, it raised concerns regarding its possible endocrine disrupting effect. The existing in vitro studies indicate that BHA presents a weak estrogenic effect and also anti-androgenic properties while an in vivo study found it to have antiestrogenic properties.    There is no sufficient data available at the moment to draw a conclusion regarding the safet...

  3. Physicochemical and Spectroscopic Characterization of Biofield Treated Butylated Hydroxytoluene

    OpenAIRE

    Trivedi, Mahendra Kumar

    2015-01-01

    The antioxidants play an important role in the preservation of foods and the management of oxidative stress related diseases by acting on reactive oxygen species and free radicals. However, their use in high temperature processed food and pharmaceuticals are limited due to its low thermal stability. The objective of the study was to use the bioeld energy treatment on butylated hydroxytoluene (BHT) i.e. antioxidant and analyse its impact on the physical, thermal, and spectral properties of BH...

  4. Biodistribution of poly(butyl 2-cyanoacrylate) nanoparticles in rabbits

    International Nuclear Information System (INIS)

    Poly(butyl 2-cyanoacrylate) nanoparticles were radiolabelled with a technetium-99m-dextran complex and the biodistribution pattern of the intravenously injected particles determined in rabbits using γ-scintigraphy. The nanoparticles were found to localise partly in the liver/spleen region (about 60%) and partly to stay in the circulation (about 30%) before degrading and releasing the radiolabel. Coating the nanoparticles with the block copolymer poloxamer 338 or poloxamine 908 did not significantly influence the biodistribution pattern. (Auth.)

  5. Preoperative Embolization of Meningiomas with N-Butyl Cyanoacrylate

    OpenAIRE

    Kominami*, S.; Watanabe, A; M. Suzuki; Mizunari, T.; Kobayashi, S; Teramoto, A.

    2012-01-01

    Meningiomas are often embolized before their surgical resection to reduce blood loss during surgery. Polyvinyl alcohol (PVA) particles have been the most frequently used material for embolization of meningiomas. We have used n-butyl cyanoacrylate (NBCA) as the first-choice material since 2001. Thirty-one meningiomas were embolized with NBCA. We report the result of embolization of meningiomas with NBCA in comparison with PVA particles.

  6. European Union Summary Risk Assessment Report - Benzyl Butyl Phthalate (BBP)

    OpenAIRE

    PAKALIN Sazan; ASCHBERGER Karin; COSGROVE Orna; PAYA PEREZ Ana; VEGRO Stefania

    2008-01-01

    This report provides a summary, with conclusions, of the risk assessment report of the substance benzyl butyl phthalate (BBP) that has been prepared by Norway in the context of Council Regulation (EEC) No. 793/93 on the evaluation and control of existing substances. For detailed information on the risk assessment principles and procedures followed, the underlying data and the literature references the reader is referred to the comprehensive Final Risk Assessment Report (Final RAR) that ca...

  7. 2-Benzhydryl-6-tert-butyl-4-methylphenol

    Directory of Open Access Journals (Sweden)

    Sungwoo Yoon

    2013-02-01

    Full Text Available The title compound, C24H26O, was prepared by the reaction between 2-tert-butyl-4-methylphenol and diphenylmethanol in the presence of sulfuric acid. Three benzene rings are attached directly to the central C—H group in a twisted propeller conformation with the local pseudo-C3 rotational axis coinciding with the C—H bond. There are three short C—H...O contacts in the molecule.

  8. Study of the butyl acetate synthesis - 1. Catalyst selection

    Directory of Open Access Journals (Sweden)

    Álvaro Orjuela Londoño

    2010-04-01

    Full Text Available In this work, a laboratory scale selection study over eight catalytic agents was made, in the acetic acid and butyl alcohol esterification reaction (seven lon exchange resins and a zeolytic solid. Considering some physicochemical characteristics as the activation pre-treating requirements, acidity, thermal stability, reaction performance, etc., it was found that macroporous ion exchange resins are the most efficient catalysts, especially Lewatit K-2431 resin.

  9. 76 FR 5696 - Fluazifop-P-butyl; Pesticide Tolerances

    Science.gov (United States)

    2011-02-02

    ... fluazifop-P-butyl in or on potato, tuber at 1.1 ppm; potato, peel (wet) at 1.1 ppm; potato, chips at 3.0 ppm... Federal Register of January 6, 2010 (75 FR 864) (FRL-8801- 5), EPA issued a notice pursuant to section 408...) at 3.5 ppm. In the Federal Register of February 4, 2010 (75 FR 5790) (FRL-8807- 5), EPA issued...

  10. GC/GCMS analysis of the petroleum ether and dichloromethane extracts of Moringa oleifera roots

    Institute of Scientific and Technical Information of China (English)

    Shaheen; Faizi; saima; sumbul; Muhammed; Ali; Versiani; Rubeena; Saleem; Aisha; Sana; Hira; Siddiqui

    2014-01-01

    Objective:To explore the phytochemical constituents from petroleum ether and diehloromethane extracts of Moringa oleifera(M.oleufera)roots using GC/GC—MS.Methods:A total of 5.11 kg fresh and undried crashed root of M.oleifera were cut into small pieces and extracted with petroleum ether and diehloromethane(20 L.each) at room temperature for 2 d.The concentrated extracts were subjected to their GC—MS analysis.Results:The GC-MS analysis of the petroleum ether and diehloromethane extracts of M.oleifern roots,which showed promising biological activities,has resulted in the identification 102 compounds.These constituents belong to 15 classes of compounds including hydrocarbons,fatty acids,esters,alcohols,isolhioeyanate.thiocyanale,pyrazine,aromalics.alkamides.cyanides,steroids,halocompounds.urea and N-hydroxyimine derivatives,unsaturated alkenamides.alkyne and indole.GC/GC-MS studies on petroleum ether extraet of the roots revealed that it contained 39 compounds,belonging to nine classes.Cyclooctasulfur S8 has been isolated as a pure compound from the extract.The major compounds identified from petroleum ether extract were trans-13-clocosene(37.9%).nonacosane(32.6%).cycloartenol(28.6%) nonadecanoic acid(13.9%) and cyclooctasulfur S8(13.9%).Dichloromethane extract of the roots was composed of 63 compounds of which nasimizinol(58.8%) along with oleic acid(46.5%),N—benzyl-N-(7—cyanato heptanamide(38.3%),N—benzyl-N—(1—chlorononyl) amide(30.3%),bis[3—benzyl prop-2-ene]-1-one(19.5%) and N.N-dibeuzyl—2-ene pent 1.5—diamide(11.6%) were the main constituents.Conclusions:This study helps to predict the formula and structure of active molecules which can be used as drugs.This result also enhances the traditional usage of M.oleifera which possesses a number of bioactive compounds.

  11. Meso-ester and carboxylic acid substituted BODIPYs with far-red and near-infrared emission for bioimaging applications

    KAUST Repository

    Ni, Yong

    2014-01-21

    A series of meso-ester-substituted BODIPY derivatives 1-6 are synthesized and characterized. In particular, dyes functionalized with oligo(ethylene glycol) ether styryl or naphthalene vinylene groups at the α positions of the BODIPY core (3-6) become partially soluble in water, and their absorptions and emissions are located in the far-red or near-infrared region. Three synthetic approaches are attempted to access the meso-carboxylic acid (COOH)-substituted BODIPYs 7 and 8 from the meso-ester-substituted BODIPYs. Two feasible synthetic routes are developed successfully, including one short route with only three steps. The meso-COOH-substituted BODIPY 7 is completely soluble in pure water, and its fluorescence maximum reaches around 650 nm with a fluorescence quantum yield of up to 15 %. Time-dependent density functional theory calculations are conducted to understand the structure-optical properties relationship, and it is revealed that the Stokes shift is dependent mainly on the geometric change from the ground state to the first excited singlet state. Furthermore, cell staining tests demonstrate that the meso-ester-substituted BODIPYs (1 and 3-6) and one of the meso-COOH-substituted BODIPYs (8) are very membrane-permeable. These features make these meso-ester- and meso-COOH-substituted BODIPY dyes attractive for bioimaging and biolabeling applications in living cells. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Experimental analysis of a Diesel Engine fuelled with Biodiesel Blend using Di-ethyl ether as fuel additives

    Directory of Open Access Journals (Sweden)

    AR.Manickam

    2014-10-01

    Full Text Available This study investigates the use of di-ethyl ether (DEE as an oxygenated additive with 20% Karanja methyl ester diesel blend (B20. Experiments were conducted to study the effect of adding 5%, 10% and 15% di-ethyl ether (DEE with Karanja methyl ester (KME on performance, emission and combustion characteristics of a direct injection diesel engine operated at a constant speed of 1500 rpm at different operating conditions. The results showed that the brake thermal efficiency slightly increased and the exhaust emissions are significantly decreased with DEE with biodiesel at full load conditions. The results revealed that an optimum blend of 10% DEE added with biodiesel resulted in a slight decrease in brake specific fuel consumption (BSFC of 8.6% while the brake thermal efficiency increased by 4.8%. DEE added with 20% biodiesel showed lower nitrogen oxide (NO emission and slightly higher carbon dioxide (CO2 emission as compared to diesel. Carbon monoxide (CO, hydrocarbon (HC and smoke emissions decreased by 40%, 26% and 12% respectively compared to B20 biodiesel. The combustion characteristics like higher cylinder pressure, heat release rate and shorter ignition delay period were observed with DEE added biodiesel at full load conditions.

  13. Space-Qualifiable Cyanate Ester Elastomer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Cornerstone Research Group, Inc. (CRG) proposes to design and develop a space-qualifiable cyanate ester elastomer for application in self-deployable space...

  14. Space-Qualifiable Cyanate Ester Elastomer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In Phase 1, CRG demonstrated the feasibility of a novel approach to prepare cyanate ester based elastomers. This approach polymerizes in-situ siloxane within a...

  15. Thermodynamic study of (alkyl esters+α,ω-alkyl dihalides) III. HmEandVmE for 20 binary mixtures {xCu-1H2u-1CO2C4H9+(1-x)α,ω-ClCH2(CH2)v-2CH2Cl}, where u=1 to 4, α=1 and v=ω=2 to 6

    International Nuclear Information System (INIS)

    In this article, the experimental data of excess molar enthalpies HmE and excess molar volumes VmE are presented for a set of 20 binary mixtures comprised of the first four butyl alkanoates (methanoate to butanoate) and five α,ω-dichloroalkanes (1,2-dichloroethane to 1,6-dichlorohexane), obtained at atmospheric pressure and at a temperature of 298.15K. The results indicate the existence of specific interactions between both kinds of compounds resulting in exothermic processes for most mixtures, except for those containing butyl methanoate which give rise to net endo/exothermic effects. The VmE are positive for mixtures of (butyl esters+1,2-dichloroethane or 1,3-dichloropropane) and negative for the remaining ones. The change in HmE with the dichloroethane chain length for a same ester is regular although the VmE presents an irregular variation. It can, therefore, be deuced from this that the mixing process involves both effects, exothermic/endothermic and expansion/contraction, simultaneously. The behaviour of the mixtures is interpreted on the basis of the results observed and attributed to different effects taking place among the molecules studied. To improve application of the UNIFAC model using the version of Dang and Tassios, average values were recalculated again for parameters of the ester/chloride interaction, distinguishing, during its application, the functional group of the acid part of the ester. In spite of this, the model does not adequately reproduce the systems' behaviour.

  16. Rapid Output Growth of Special Acrylic Esters

    Institute of Scientific and Technical Information of China (English)

    Wang Lianzhi

    2007-01-01

    @@ Acrylic esters are usually classified into general-purpose varieties and special varieties. The production and application of general-purpose varieties is already quite matured in the world and their output growth tends to be flat. Owing to the development of coatings, electronics, automobiles,textiles, printing and construction sectors, especially the application of radiation curing technology in various sectors, special acrylic esters have developed rapidly.

  17. Synthesis of a new energetic nitrate ester

    Energy Technology Data Exchange (ETDEWEB)

    Chavez, David E [Los Alamos National Laboratory

    2008-01-01

    Nitrate esters have been known as useful energetic materials since the discovery of nitroglycerin by Ascanio Sobrero in 1846. The development of methods to increase the safety and utility of nitroglycerin by Alfred Nobel led to the revolutionary improvement in the utility of nitroglycerin in explosive applications in the form of dynamite. Since then, many nitrate esters have been prepared and incorporated into military applications such as double-based propellants, detonators and as energetic plasticizers. Nitrate esters have also been shown to have vasodilatory effects in humans and thus have been studied and used for treatments of ailments such as angina. The mechanism of the biological response towards nitrate esters has been elucidated recently. Interestingly, many of the nitrate esters used for military purposes are liquids (ethylene glycol dinitrate, propylene glycol dinitrate, etc). Pentaerythritol tetranitrate (PETN) is one of the only solid nitrate esters, besides nitrocellulose, that is used in any application. Unfortunately, PETN melting point is above 100 {sup o}C, and thus must be pressed as a solid for detonator applications. A more practical material would be a melt-castable explosive, for potential simplification of manufacturing processes. Herein we describe the synthesis of a new energetic nitrate ester (1) that is a solid at ambient temperatures, has a melting point of 85-86 {sup o}C and has the highest density of any known nitrate ester composed only of carbon, hydrogen, nitrogen and oxygen. We also describe the chemical, thermal and sensitivity properties of 1 as well as some preliminary explosive performance data.

  18. Comparative Environmental Performance of Two-Diesel-Fuel Oxygenates: Dibutyl Maleate (DBM) and Triproplyene Glycol Monomethyl Ether (TGME)

    Energy Technology Data Exchange (ETDEWEB)

    Layton, D.W.; Marchetti, A.A.

    2001-10-01

    Many studies have shown that the addition of oxygen bearing compounds to diesel fuel can significantly reduce particulate emissions. To assist in the evaluation of the environmental performance of diesel-fuel oxygenates, we have implemented a suite of diagnostic models for simulating the transport of compounds released to air, water, and soils/groundwater as well as regional landscapes. As a means of studying the comparative performance of DBM and TGME, we conducted a series of simulations for selected environmental media. Benzene and methyl tertiary butyl ether (MTBE) were also addressed because they represent benchmark fuel-related compounds that have been the subject of extensive environmental measurements and modeling. The simulations showed that DBM and TGME are less mobile in soil because of reduced vapor-phase transport and increased retention on soil particles. The key distinction between these two oxygenates is that DBM is predicted to have a greater potential than TGME for aerobic biodegradation, based on chemical structure.

  19. Allied, MGC link on cyanate esters

    International Nuclear Information System (INIS)

    In the latest of a line of joint ventures in its plastics business, Allied Signal has reached agreement with Mitsubishi Gas Chemical (MGC) to jointly develop thermoset cyanate ester resins and blends. The deal will involve further development of Allied Signal's Primaset phenol-formaldehyde cyanate ester resins, a new entrant in the thermoset arena. Although the Primaset resins were discovered in the 1960s, this would be the first time they are available commercially. The deal will marry Primaset technology with MGC's Skylex bisphenol A cyanate ester resins, says Fred DiAntonis, director/advanced materials at Allied Signal. The two firms are looking at marketing blends of the two materials. The potential market for these resins, used commercially by the electronics industry in printed circuit boards and by the aerospace industry in composites, is significant, says Robert P. Viarengo, Allied Signal president/performance materials. By aligning ourselves with MGC, the world leader in cyanate ester resin, we anticipate moving forward aggressively. The main competitor is Ciba, which acquired bisphenol A cyanate ester resins with its purchase of Rhone-Poulenc's high temperature resins business. DiAntonis estimates the market for cyanate ester resins could be worth $150 million by the end of the decade, although development costs have been in the tens of millions of dollars range

  20. Effective utilization of B20 blend with diethyl ether and ethanol as oxygenated additives

    Directory of Open Access Journals (Sweden)

    Upadrasta-Satya Vara-Prasad

    2011-01-01

    Full Text Available In the recent times' fatty acid methyl ester popularly called as biodiesel has become more prominent alternate fuel for compression ignition engines based on a single fuel concept. Since, use of neat biodiesel on a large scale is raising certain difficulties and is being adopted in a blended form with petro-diesel fuel and B20 blend has become standardized. However, the HC and NOx emissions of B20 are still on the higher side. Present work aims at experimental evaluation of a single cylinder water-cooled diesel engine by adopting various proportions of ethanol and diethyl ether blends in order to improve performance and emission characteristics of B20 blend. Besides employing different amounts of ethanol and diethyl ether, simultaneous influence of injector nozzle hole size and fuel injection pressure are also investigated to arrive at an optimum configuration. Brake specific fuel consumption and hydrocarbon emissions values are lower with B20 and DEE 5 whereas B20 with DEE15 yielded lower NOx emissions. It is observed that addition of oxygenates have improved the combustion process and lower emissions are obtained. The present investigation revealed that blends with oxygenated additives having higher Cetane rating are superior to neat blend.

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

    OpenAIRE

    Gibran da Cunha Vasconcelos; Rogerio Lago Mazur; Edson Cocchieri Botelho; Mirabel Cerqueira Rezende; Michelle Leali Costa

    2010-01-01

    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 dev...

  2. Synthesis, Anti-HCV, Antioxidant and Reduction of Intracellular Reactive Oxygen Species Generation of a Chlorogenic Acid Analogue with an Amide Bond Replacing the Ester Bond

    Directory of Open Access Journals (Sweden)

    Ling-Na Wang

    2016-06-01

    Full Text Available Chlorogenic acid is a well known natural product with important bioactivities. It contains an ester bond formed between the COOH of caffeic acid and the 3-OH of quinic acid. We synthesized a chlorogenic acid analogue, 3α-caffeoylquinic acid amide, using caffeic and quinic acids as starting materials. The caffeoylquinc acid amide was found to be much more stable than chlorogenic acid and showed anti-Hepatitis C virus (anti-HCV activity with a potency similar to chlorogenic acid. The caffeoylquinc acid amide potently protected HepG2 cells against oxidative stress induced by tert-butyl hydroperoxide.

  3. Efficacy of oral active ether lipid analogs of cidofovir in a lethal mousepox model

    International Nuclear Information System (INIS)

    Cidofovir (CDV) is a highly effective inhibitor of orthopoxvirus replication and may be used intravenously to treat smallpox or complications arising from the smallpox vaccine under an investigational new drug application (IND). However, CDV is absorbed poorly following oral administration and is inactive orally. To improve the bioavailability of CDV, others synthesized alkoxyalkanol esters of CDV and observed >100-fold more activity than unmodified CDV against cowpox, vaccinia, and variola virus (VARV) replication. These ether lipid analogs of CDV have high oral bioavailability in mice. In this study, we compared the oral activity of CDV with the hexadecyloxypropyl (HDP)-, octadecyloxyethyl-, oleyloxypropyl-, and oleyloxyethyl-esters of CDV in a lethal, aerosol ectromelia virus (ECTV) challenge model in A/NCR mice. Octadecyloxyethyl-CDV appeared to be the most potent CDV analog as a dose regimen of 5 mg/kg started 4 h following challenge completely blocked virus replication in spleen and liver, and protected 100% of A/NCR mice, although oral, unmodified CDV was inactive. These results suggest that this family of compounds deserves further evaluation as poxvirus antiviral

  4. Emergent gravity and ether-drift experiments

    CERN Document Server

    Consoli, M

    2009-01-01

    In principle, ether-drift experiments could distinguish phenomenologically emergent-gravity approaches, where an effective curvature emerges from hydrodynamic distortions of the same physical, flat-space vacuum, from the more conventional scenario where curvature is considered a fundamental property of space-time down to extremely small length scales and the speed of light represents a universal constant. From an experimental point of view, in this particular context, besides time modulations that might be induced by the Earth's rotation (and its orbital revolution), one should also consider the possibility of random fluctuations of the signal. These might reflect the stochastic nature of the underlying 'quantum ether' and be erroneously interpreted as mere instrumental noise. To test the present interpretation, we have extracted the mean amplitude of the signal from various experiments with different systematics, operating both at room temperature and in the cryogenic regime. They all give the same consisten...

  5. Synthesis of New Liquid Crystalline Diglycidyl Ethers

    Directory of Open Access Journals (Sweden)

    Issam Ahmed Mohammed

    2012-01-01

    Full Text Available The phenolic Schiff bases I–VI were synthesized by condensation reactions between various diamines, namely o-dianisidine, o-tolidine and ethylenediamine with vanillin or p-hydroxybenzaldehyde and subsequent reactions between these phenolic Schiff bases and epichlorohydrin to produce new diglycidyl ethers Ia–VIa. The structures of these compounds were confirmed by CHN, FT-IR, 1H-NMR, and 13C-NMR spectroscopy. Their thermotropic liquid crystalline behavior was studied using differential scanning calorimetry (DSC and polarizing optical microscopy (POM. All the diglycidyl ethers prepared exhibit nematic mesophases, except for Va and VIa, which did not show any transition mesophases, but simply flow to liquids.

  6. Contribution to the study of uranyl salts in butyl phosphate solutions

    International Nuclear Information System (INIS)

    A spectroscopic study in the normal infrared region and involving the following associations: tri-alkyl phosphates (tri-butyl, tri-ethyl, tri-methyl), uranyl salts (nitrate, chloride, acetate) has confirmed the existence of an interaction between the phosphoryl group and the uranium atom, as shown by a movement of absorption band for the valency P = 0 from ∼ 1270 cm-1 to ∼ 1180 cm-1. A study of the preparation, analysis and spectroscopy of the solids obtained by the precipitation of uranyl salts by acid butyl phosphates has been carried out. By infrared spectrophotometry it has been shown that the tri-butyl and di-butyl phosphates are associated in non-polar diluents even before the uranium is introduced. The extraction of uranyl salts from acid aqueous solutions by a diluted mixture of tri-butyl and di-butyl phosphates proceeds by different mechanisms according to the nature of the ion (nitrate or chloride). (author)

  7. Synthesis of New Liquid Crystalline Diglycidyl Ethers

    OpenAIRE

    Issam Ahmed Mohammed; Rashidah Mohamed Hamidi

    2012-01-01

    The phenolic Schiff bases I–VI were synthesized by condensation reactions between various diamines, namely o-dianisidine, o-tolidine and ethylenediamine with vanillin or p-hydroxybenzaldehyde and subsequent reactions between these phenolic Schiff bases and epichlorohydrin to produce new diglycidyl ethers Ia–VIa. The structures of these compounds were confirmed by CHN, FT-IR, 1H-NMR, and 13C-NMR spectroscopy. Their thermotropic liquid crystalline behavior was studied using differential scannin...

  8. Ether bridge formation in loline alkaloid biosynthesis

    OpenAIRE

    Pan, Juan; Bhardwaj, Minakshi; Faulkner, Jerome R.; Nagabhyru, Padmaja; Charlton, Nikki D.; Higashi, Richard M.; Miller, Anne-Frances; Young, Carolyn A; Grossman, Robert B.; Schardl, Christopher L

    2013-01-01

    Lolines are potent insecticidal agents produced by endophytic fungi of cool-season grasses. These alkaloids are composed of a pyrrolizidine ring system and an uncommon ether bridge linking carbons 2 and 7. Previous results indicated that 1-aminopyrrolizidine was a pathway intermediate. We used RNA interference to knock down expression of lolO, resulting in the accumulation of a novel alkaloid identified as exo-1-acetamidopyrrolizidine based on high-resolution MS and NMR. Genomes of endophytes...

  9. Fluoroalkylation of aryl ether perfluorocyclobutyl polymers

    OpenAIRE

    Ligon, Clark; Ameduri, Bruno; Boutevin, Bernard; Smith, Dennis

    2008-01-01

    Post functionalization of aryl ether perfluorocyclobutyl (PFCB) polymers with fluoroalkyl side chains was accomplished with Umemoto's FITS reagents. The fluoroalkylated PFCB polymers (20 % functionalized) showed increases in both hydrophobicity and oleophobicity. Static contact angle for hexadecane was increased after fluoroalkylation from 0° to greater than 30° for the two PFCB polymers tested. Increased oil repellency makes these materials potential candidates for various coatings applicati...

  10. 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: 2.828, year: 2014

  11. Catalytic intermolecular hydroamination of vinyl ethers

    OpenAIRE

    Pahadi, Nirmal K.; Tunge, Jon A.

    2009-01-01

    This manuscript details the development of a palladium-catalyzed hydroamination of vinyl ethers. It is proposed that palladium catalyzes the hydroamination via Bronsted base catalysis, where palladium is protonated by the relatively acidic sulfonamide to generate a palladium hydride as well as the active anionic sulfonamide nucleophile. Thus, this process is distinct from known palladium-catalyzed hydroaminations of styrene derivatives that utilize less acidic amines.

  12. Poly(Arylene Ether Imidazole) Surface Films

    Science.gov (United States)

    Connell, John W.; Towell, Timothy W.; Tompkins, Stephen S.

    1993-01-01

    Films adhere well to some substrates, provide smooth surfaces, and facilitate release from molds. Thin films of thermoplastic poly(arylene ether imidazole)s (PAEI's) particularly suitable for use as surface modifiers for graphite/epoxy or graphite/bismaleimide composite panels. Molecule of PAEI includes imidazole groups along its backbone that co-cure with epoxies or bismaleimides during processing. Films thermally stable and resistant to bombardment by energetic electrons.

  13. 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.

  14. Alkyl aryl ethers in lignite solubilization

    Energy Technology Data Exchange (ETDEWEB)

    Mustral, A.M.; Cebolla, V.L.; Gavilan, J.M.

    1985-03-01

    The FT-I.R. and /sup 1/H N.M.R. spectroscopic analyses of oils or maltenes from a Spanish lignite (Utrillas, Teruel), are reported. These oils were obtained by depolymerization with alkyl aromatic ethers (anisole, 3-methyl anisole and 1,3-dimethoxybenzene) catalyzed by Lewis acids ZnCl/sub 2/, AlCl/sub 3/, SbCl/sub 3/ and BF/sub 3/ (as boron trifluoride etherate), at atmospheric pressure and temperatures <220/sup 0/C. Bands due to aromatic ethers in the I.R. and N.M.R. spectra of the oils obtained by depolymerization indicate solvent incorporation. Oils obtained by direct lignite extraction showed 25% aromatic H and some H /sub i/ (approx. = 3%) without OH groups. These appeared in some oils obtained by depolymerization with AlCl/sub 3/ and were due to secondary reactions with the aromatic extract. Oils derived from processes with good yields showed increases in aromaticity. The extent of substitution of aromatic rings in oils obtained by depolymerization was less than for oils directly extracted. All the oils studied show a low degree of condensation.

  15. Molecular recognition study of Carbamazepine, antiseizure drug, by p-t-butyl calix(8)arene

    Science.gov (United States)

    Meenakshi, C.; Jayabal, P.; Ramakrishnan, V.

    2014-03-01

    The formation of inclusion complex of Carbamazepine, a antiseizure drug molecule, with the supra molecule, p-t-butyl calix(8)arene was studied. p-t-Butyl calix(8)arene was the host molecule and Carbamazepine was the guest molecule. Optical absorption spectral studies were carried out to study the molecular recognition properties of p-t-butyl calix(8)arene with Carbamazepine. The stochiometry of the host-guest complex and the binding constant were determined.

  16. Detection of testosterone esters in blood.

    Science.gov (United States)

    Forsdahl, Guro; Erceg, Damir; Geisendorfer, Thomas; Turkalj, Mirjana; Plavec, Davor; Thevis, Mario; Tretzel, Laura; Gmeiner, Günter

    2015-01-01

    Injections of synthetic esters of testosterone are among the most common forms of testosterone application. In doping control, the detection of an intact ester of testosterone in blood gives unequivocal proof of the administration of exogenous testosterone. The aim of the current project was to investigate the detection window for injected testosterone esters as a mixed substance preparation and as a single substance preparation in serum and plasma. Furthermore, the suitability of different types of blood collection devices was evaluated. Collection tubes with stabilizing additives, as well as non-stabilized serum separation tubes, were tested. A clinical study with six participants was carried out, comprising a single intramuscular injection of either 1000 mg testosterone undecanoate (Nebido(®)) or a mixture of 30 mg testosterone propionate, 60 mg testosterone phenylpropionate, 60 mg testosterone isocaproate, and 100 mg testosterone decanoate (Sustanon(®)). Blood was collected throughout a testing period of 60 days. The applied analytical method for blood analysis included liquid-liquid extraction and preparation of oxime derivatives, prior to TLX-sample clean-up and liquid chromatography-tandem mass spectrometry (LC-MS/MS) detection. All investigated testosterone esters could be detected in post-administration blood samples. The detection time depended on the type of ester administered. Furthermore, results from the study show that measured blood concentrations of especially short-chained testosterone esters are influenced by the type of blood collection device applied. The testosterone ester detection window, however, was comparable. PMID:26695486

  17. Molecular recognition of isomeric protonated amino acid esters monitored by ESI-mass spectrometry

    Directory of Open Access Journals (Sweden)

    Andrea Liesenfeld

    2014-04-01

    Full Text Available Two new 9,9’-spirobifluorene-derived crown ethers were prepared and used to recognise constitutionally isomeric amino acid derivatives. The performance of the receptors was evaluated by ESI-mass spectrometry using the isomer labelled guest method (ILGM. This method revealed the preferred binding of L-norleucine and L-leucine compared to L-isoleucine for both receptors. Furthermore, non-covalent isotope effects demonstrate the relevance of dispersive interactions for the overall binding event. These effects also provide hints for the relative spatial orientation of the guest molecules within the host–guest complex, and thereby prove the importance of the spirobifluorene moiety for the observed binding of the protonated amino acid esters.

  18. Molecular recognition of isomeric protonated amino acid esters monitored by ESI-mass spectrometry.

    Science.gov (United States)

    Liesenfeld, Andrea; Lützen, Arne

    2014-01-01

    Two new 9,9'-spirobifluorene-derived crown ethers were prepared and used to recognise constitutionally isomeric amino acid derivatives. The performance of the receptors was evaluated by ESI-mass spectrometry using the isomer labelled guest method (ILGM). This method revealed the preferred binding of L-norleucine and L-leucine compared to L-isoleucine for both receptors. Furthermore, non-covalent isotope effects demonstrate the relevance of dispersive interactions for the overall binding event. These effects also provide hints for the relative spatial orientation of the guest molecules within the host-guest complex, and thereby prove the importance of the spirobifluorene moiety for the observed binding of the protonated amino acid esters. PMID:24778737

  19. COMBUSTION ANALYSIS OF ALGAL OIL METHYL ESTER IN A DIRECT INJECTION COMPRESSION IGNITION ENGINE

    Directory of Open Access Journals (Sweden)

    HARIRAM V.

    2013-02-01

    Full Text Available Algal oil methyl ester was derived from microalgae (Spirulina sp. The microalga was cultivated in BG 11 media composition in a photobioreactor. Upon harvesting, the biomass was filtered and dried. The algal oil was obtained by a two step solvent extraction method using hexane and ether solvent. Cyclohexane was added to biomass to expel the remaining algal oil. By this method 92% of algal oil is obtained. Transesterification process was carried out to produce AOME by adding sodium hydroxide and methanol. The AOME was blended with straight diesel in 5%, 10% and 15% blend ratio. Combustion parameters were analyzed on a Kirloskar single cylinder direct injection compression ignition engine. The cylinder pressure characteristics, the rate of pressure rise, heat release analysis, performance and emissions were studied for straight diesel and the blends of AOME’s. AOME 15% blend exhibits significant variation in cylinder pressure and rate of heat release.

  20. Extraction of phthalate esters from water and beverages using a graphene-based magnetic nanocomposite prior to their determination by HPLC

    International Nuclear Information System (INIS)

    We have developed a highly sensitive microextraction method for the preconcentration of some phthalate esters such as diethyl phthalate, di-n-propylphthalate, di-n-butyl-phthalate, dicyclohexyl-phthalate, and diethyl-hexyl phthalate prior to their determination by HPLC. It is based on a magnetic graphene nanocomposite as an effective adsorbent. The effects of the amount of the extractant composite employed, extraction time, pH values, salt concentration and desorption conditions were investigated. Under the optimum conditions, the enrichment factors range from 1574 to 2880. Response is linear in the concentration range from 0. 1 to 50 ng mL-1. The limits of detection (at S/N = 3) were between 0. 01 and 0. 04 ng mL-1. The method was successfully applied to the determination of five phthalate esters in water and beverage samples. (author)

  1. ESTER - a European source term evaluation system

    International Nuclear Information System (INIS)

    The Commission of the European Communities (CEC) sponsors considerable model development and validation in the area of Light Water Reactor (LWR) source term, and naturally wishes to see the results used as widely as possible. It also has a role in fostering collaboration between European teams involved in source term analysis, for which purpose Phebus-Fission Product (FP) is acting as a focal point. To further both aims the Joint Research Centre (JRC) decided in 1989 to sponsor the development of the best-estimate code ESTER, which is both a software environment and a set of coupled source term modules which when completed should offer potentialities not currently available within Europe. This paper describes first the overall architecture of ESTER, then the component parts: the tools and services, the user interface, and the modules which perform the physics and chemistry calculations, emphasizing the design choices which have been made. The quality assurance system for the whole system is also reviewed. Contributions from the model developers, both underway, and expected, are then surveyed in the context of the overall development of ESTER, and the planning of the creation and extension of ESTER is given. The paper closes with some proposals for sharing ESTER within Europe and for ensuring its maintenance and continued rational development. (Author)

  2. Anaerobic degradation kinetics of a cholesteryl ester.

    Science.gov (United States)

    Gutiérrez, S; Viñas, M

    2003-01-01

    The most important components of wool scouring effluent grease are esters of sterols. Cholesteryl palmitate (CP) is the main ester in this grease. In this paper, the influence of the ester concentration in the anaerobic digestion and the relative rate of the different degradation steps, are studied. The experiment was carried out to measure methane production in the anaerobic degradation of acetate, palmitic acid (PA) and CP. A first-order kinetic model was assumed for hydrolysis and Monod models were assumed for both the methanogenic and acetogenic steps. Maximum hydrolysis rate was found to be around 20 times faster than the maximum methanogenic reaction rate during the experience. The lanolin emulsion drop size effect was also evaluated employing fine and coarse stock lanolin emulsions and no adapted sludge. Concentrations of 13.7 to 4.6 gCOD x l(-1) were employed. In a previous study, the effect of palmitic acid emulsion size was found important when similar sludge was tested. When esters are degraded, a significant effect of drop size on the degradation rate was not found. The difference between CP and PA emulsions behavior could be due to the fact that cholesterol produced during the ester degradation has a protective effect on the sludge. PMID:14640211

  3. Synthesis of bioreductive esters from fungal compounds.

    Science.gov (United States)

    Weerapreeyakul, Natthida; Anorach, Rutchayaporn; Khuansawad, Thidarut; Yenjai, Chavi; Isaka, Masahiko

    2007-06-01

    Four new bioreductive esters (7-10) have been synthesized. Their structures composed of trimethyl lock containing quinone propionic acid with an ester linkage to the fungal cytotoxic compounds; preussomerin G (1), preussomerin I (2), phaseolinone (3) and phomenone (4). The synthesized esters are aimed to act via reductive activation specifically at the cancer cells, resulting from hypoxia and overexpression of reductases. Hence, the toxicity will be lessened during distribution across the normal cells. The anticancer activity was determined in cancer cell lines with reported reductase i.e., BC-1 cells and NCI-H187 as well as in non-reductase containing cancer cells; KB cells. When considering each cell lines, result showed that structure modification giving to 7-10 led to less cytotoxicity than their parent compounds (1-4). Both 7 and 8 were strongly cytotoxic (IC50 < or = 5 microg/ml) to NCI-H187, whereas 9 and 10 were moderately cytotoxic (IC50 = 6-10 microg/ml) to BC-1 cells. Additional study of stability of represented phenolic ester (8) and an alcoholic ester (9) were performed. Result illustrated that both 8 and 9 were stable in the presence of esterase. Therefore, the cytotoxicity of the synthesized compounds (8-10) might be due to partial bioreductive activation in the cancer cells. PMID:17541198

  4. Electroless nickel-phosphorus coating on poly (ether ether ketone)/carbon nanotubes composite

    Science.gov (United States)

    Zhai, Tong; Di, Lizhi; Yang, De'an

    2014-05-01

    In order to improve electromagnetic shielding property of poly (ether ether ketone)/carbon nanotubes composite, a nickel-phosphorus coating was covered on the composite by electroless plating. The morphologies of the substrates and the coatings were characterized by SEM. XPS was performed to analyze the surface composition and chemical states before and after chemical etching. The results showed that lots of microscopic holes appeared and evenly distributed on the surface, and the concentration of hydrophilic groups on the surface increased after the composite was etched. Thermal shock test showed that the adhesive strength between the coating and the composite was good.

  5. Azidated Ether-Butadiene-Ether Block Copolymers as Binders for Solid Propellants

    Science.gov (United States)

    Cappello, Miriam; Lamia, Pietro; Mura, Claudio; Polacco, Giovanni; Filippi, Sara

    2016-07-01

    Polymeric binders for solid propellants are usually based on hydroxyl-terminated polybutadiene (HTPB), which does not contribute to the overall energy output. Azidic polyethers represent an interesting alternative but may have poorer mechanical properties. Polybutadiene-polyether copolymers may combine the advantages of both. Four different ether-butadiene-ether triblock copolymers were prepared and azidated starting from halogenated and/or tosylated monomers using HTPB as initiator. The presence of the butadiene block complicates the azidation step and reduces the storage stability of the azidic polymer. Nevertheless, the procedure allows modifying the binder properties by varying the type and lengths of the energetic blocks.

  6. Tris(tert-butyl isocyanide-κC)carbonylnickel(0)

    OpenAIRE

    Wolfgang Imhof; Helmar Görls; Kathi Halbauer

    2008-01-01

    The title compound, [Ni(C5H9N)3(CO)], was prepared from Ni(CO)4 and a tenfold excess of tert-butyl isocyanide. It crystallizes with two symmetry-independent mol­ecules per asymmetric unit. The central Ni atom of each independent mol­ecule has a nearly perfect tetra­hedral coordination environment, comprising one carbon monoxide and three isocyanide ligands. The title compound is the first structurally characterized Ni0 compound with a mixed CO/RNC coordination.

  7. A Study of the Teratogenicity of Butylated Hydroxyanisole on Rabbits

    DEFF Research Database (Denmark)

    Hansen, Ernst; Meyer, Otto A.

    1978-01-01

    A teratogenicity study on butylated hydroxyanisole (BHA) was carried out in SPF New Zealand White rabbits. BHA was given by gavage from day 7–18 of the gestation period in doses of 0, 50, 200 and 400 mg/kg body wt./day. The fetuses were removed on day 28. No effect related to the treatment with B...... was observed on the number of corpora luteae, implantations, fetuses dead or alive, or on gross malformations, skeletal and internal malformations, and on the weight of the fetuses....

  8. tert-Butyl N-(thiophen-2-ylcarbamate

    Directory of Open Access Journals (Sweden)

    Gene C. Hsu

    2013-09-01

    Full Text Available In the title compound, C9H13NO2S, the dihedral angle between the thiophene ring and the carbamate group is 15.79 (14°. In the crystal structure, intramolecular C—H...O interactions in tandem with the tert-butyl groups render the packing of adjacent molecules in the [001] direction nearly perpendicular [the angle between adjacent thiophene rings is 74.83 (7°]. An intermolecular N—H...O hydrogen bond gives rise to a chain extending along [001]. The crystal studied was found to be a racemic twin.

  9. Absorption of some glycol ethers through human skin in vitro.

    OpenAIRE

    Dugard, P H; M. Walker; Mawdsley, S J; Scott, R.C.

    1984-01-01

    To assist evaluation of the hazards of skin contact with selected undiluted glycol ethers, their absorption across isolated human abdominal epidermis was measured in vitro. Epidermal membranes were set up in glass diffusion cells and, following an initial determination of permeability to tritiated water, excess undiluted glycol ether was applied to the outer surface for 8 hr. The appearance of glycol ether in an aqueous "receptor" phase bathing the underside of the epidermis was quantified by...

  10. SYNTHESIS OF POLY ( ETHER-URETHANE) CONTAINING PENDANT AMINO GROUP

    Institute of Scientific and Technical Information of China (English)

    WU Jinhuang; SUN Yanhui; FENG Xinde

    1989-01-01

    This paper is concerned with the synthesis of poly (ether-urethane) with pendant amino groups. The copolyether produced by ring opening copolymerization of tetrahydrofuran and epibromohydrin was treated with sodium azide in dimethylformamide to form azido substituted copolyether. The poly (ether-urethane) made from it was subjected to reduction reaction to convert azido group to amino group. The stress-strain behavior and dynamic-mechanical properties of poly (ether-urethane) containing pendant amino groups were studied.

  11. Theoretical study of the asymmetric phase-transfer mediated epoxidation of chalcone catalyzed by chiral crown ethers derived from monosaccharides

    Science.gov (United States)

    Makó, Attila; Menyhárd, Dóra K.; Bakó, Péter; Keglevich, György; Tőke, László

    2008-12-01

    The synthesis of a novel, optically active crown ether derived from α- D-altropyranoside is described. A significantly different asymmetric induction was generated by the α- D-glucopyranoside-, α- D-mannopyranoside- and α- D-altropyranoside-based chiral crown catalysts in the epoxidation of trans-chalcone with tert-butyl hydroperoxide under phase-transfer catalytic conditions. It was shown that absolute configuration of the crown-ring fused carbon atoms of the monosaccharides has a great impact on the enantioselectivity. The asymmetric induction could be well explained by considering the possible mechanistic pathway. Molecular modeling (MCMM) and subsequent DFT calculations - in accordance with the experimental results - indicate that the use of glucopyranoside-based catalyst 1 and that of mannopyranoside-based crown ether 2 results in the preferred formation of the opposite antipodes (2 R,3 S and 2 S,3 R, respectively) of the corresponding epoxyketone. At the same time, practically no asymmetric induction was proved if altropyranoside-based crown 3 is applied as the catalyst. The computational results are in qualitative agreement with the experimental data.

  12. Removal of technetium from alkaline nuclear-waste media by a solvent-extraction process using crown ethers

    International Nuclear Information System (INIS)

    Crown ethers dissolved in suitably modified aliphatic kerosene diluents can be employed to extract technetium as pertechnetate anion (TcO4-) with good extraction ratios from realistic simulants of radioactive alkaline nitrate waste. The modifiers utilized are non-halogenated and non-volatile, and the technetium can be removed from the solvent by stripping using water. The crown ethers bis-4,4'(5')[(tert-butyl)cyclohexano]-18-crown-6 (di-t-BuCH18C6) and dicyclohexano-18-crown-6 (DCH18C6) provide stronger TcO4- extraction than dicyclohexano-21-crown-7 and 4-tert-butylcyclohexano 15-crown-5. Whereas DCH18C6 provides somewhat higher TcO4- extraction ratios than the more lipophilic di-t-BuCH18C6 derivative, the latter was selected for further study owing to its lower distribution to the aqueous phase. Particularly good extraction and stripping results were obtained with di-t-BuCH 18C6 at 0.02 M in a 2:1 vol/vol blend of tributyl phosphate and Isopar reg-sign M. Using this solvent, 98.9% of the technetium contained (at 6 x 10-5 M) in a Double-Shell Slurry Feed (DSSF) Hanford tank waste simulant was removed following two cross-current extraction contacts. Two cross-current stripping contacts with deionized water afforded removal of 99.1% of the technetium from the organic solvent

  13. On the predictive capabilities of CPA for applications in the chemical industry: Mulficomponent mixtures containing methyl-methacrylate, dimethyl-ether or acetic acid

    DEFF Research Database (Denmark)

    Tsivintzelis, Ioannis; Kontogeorgis, Georgios

    2014-01-01

    with acetic acid, esters, ethers and alcohols, and in this case for water-acetic acid the CPA-Huron Vidal (CPA-HV) version of the model is used. For the latter binary mixture, new CPA-HV binary parameter sets are estimated using, among others, data for activity coefficients at infinite dilutions. The...... recommended at the end for modeling ternary or multicomponent mixtures containing acetic acid and water....... mixtures exhibiting vapor-liquid (VLE) and/or liquid-liquid (LLE) equilibrium. The first two cases include mixtures of methyl-methacrylate with acetone or methanol and dimethyl-ether with ethanol, respectively. In these two cases, the classical form of CPA is used. The third case involves aqueous mixtures...

  14. Non-ideal behaviour of a room temperature ionic liquid in an alkoxyethanol or poly ethers at T = (298.15 to 318.15) K

    International Nuclear Information System (INIS)

    Non-ideal behaviour of 1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF6] in ethylene glycol monomethyl ether; CH3OCH2CH2OH (EGMME), ethylene glycol dimethyl ether; CH3OCH2CH2OCH3 (EGDME) and diethylene glycol dimethyl ether; CH3(OCH2CH2)2OCH3 (DEGDME) have been investigated over the whole composition range at T = (298.15 to 318.15) K. To gain insight into the mixing behaviour, results of density measurements were used to estimate excess molar volumes, VmE, apparent molar volumes, Vφ,i, partial molar volumes, V-barm,i, excess partial molar volumes, V-barm,iE, and their limiting values at infinite dilution, Vφ,i∞, V-barm,i∞, and V-barm,iE,∞, respectively. Volumetric results have been analyzed in the light of Prigogine-Flory-Patterson (PFP) statistical mechanical theory. Measurements of refractive indices n were also performed for all the binary mixtures over whole composition range at T = 298.15 K. Deviations in refractive indices Δφn and the deviation of molar refraction ΔxR have been calculated from experimental data. Refractive indices results have been correlated with volumetric results and have been interpreted in terms of molecular interactions. Excess properties are fitted to the Redlich-Kister polynomial equation to obtain the binary coefficients and the standard errors

  15. Thermodynamic properties of 1-butyl-3-methylpyridinium tetrafluoroborate

    Energy Technology Data Exchange (ETDEWEB)

    Safarov, Javid, E-mail: javid.safarov@uni-rostock.de [Institute of Technical Thermodynamics, University of Rostock, Albert-Einstein-Str. 2, D-18059 Rostock (Germany); Department of Heat and Refrigeration Techniques, Azerbaijan Technical University, H. Javid Avn. 25, AZ1073 Baku (Azerbaijan); Kul, Ismail [Department of Chemistry, Department of Biochemistry, Widener University, One University Place, Chester, PA 19013 (United States); El-Awady, Waleed A. [Department of Heat and Refrigeration Techniques, Azerbaijan Technical University, H. Javid Avn. 25, AZ1073 Baku (Azerbaijan); Mechanical Power Engineering Department, Mansoura Univeristy, Mansoura (Egypt); Shahverdiyev, Astan [Department of Heat and Refrigeration Techniques, Azerbaijan Technical University, H. Javid Avn. 25, AZ1073 Baku (Azerbaijan); Hassel, Egon [Institute of Technical Thermodynamics, University of Rostock, Albert-Einstein-Str. 2, D-18059 Rostock (Germany)

    2011-09-15

    Highlights: > (p, {rho}, T) data of 1-butyl-3-methylpyridinium tetrafluoroborate are estimated. > The measurements were carried out with a vibration-tube densimeter. > The thermomechanical coefficients were calculated. - Abstract: Pressure, density, temperature (p, {rho}, T) data of 1-butyl-3-methylpyridinium tetrafluoroborate [C4mpyr][BF{sub 4}] at T = (283.15 to 393.15) K and pressures up to p = 100 MPa are reported with an estimated experimental relative combined standard uncertainty of {Delta}{rho}/{rho} = {+-}(0.01 to 0.08)% in density. The measurements were carried out with a newly constructed Anton-Paar DMA HPM vibration-tube densimeter. The system was calibrated using double-distilled water, methanol, toluene and aqueous NaCl solutions. An empirical equation of state for fitting of the (p, {rho}, T) data of [C4mpyr][BF{sub 4}] has been developed as a function of pressure and temperature to calculate the thermal properties of the ionic liquid (IL), such as isothermal compressibility, isobaric thermal expansibility, differences in isobaric and isochoric heat capacities, thermal pressure coefficient and internal pressure. Internal pressure and the temperature coefficient of internal pressure data were used to make conclusions on the molecular characteristics of the IL.

  16. Thermodynamic properties of 1-butyl-3-methylpyridinium tetrafluoroborate

    International Nuclear Information System (INIS)

    Highlights: → (p, ρ, T) data of 1-butyl-3-methylpyridinium tetrafluoroborate are estimated. → The measurements were carried out with a vibration-tube densimeter. → The thermomechanical coefficients were calculated. - Abstract: Pressure, density, temperature (p, ρ, T) data of 1-butyl-3-methylpyridinium tetrafluoroborate [C4mpyr][BF4] at T = (283.15 to 393.15) K and pressures up to p = 100 MPa are reported with an estimated experimental relative combined standard uncertainty of Δρ/ρ = ±(0.01 to 0.08)% in density. The measurements were carried out with a newly constructed Anton-Paar DMA HPM vibration-tube densimeter. The system was calibrated using double-distilled water, methanol, toluene and aqueous NaCl solutions. An empirical equation of state for fitting of the (p, ρ, T) data of [C4mpyr][BF4] has been developed as a function of pressure and temperature to calculate the thermal properties of the ionic liquid (IL), such as isothermal compressibility, isobaric thermal expansibility, differences in isobaric and isochoric heat capacities, thermal pressure coefficient and internal pressure. Internal pressure and the temperature coefficient of internal pressure data were used to make conclusions on the molecular characteristics of the IL.

  17. Thermophysical properties of 1-butyl-4-methylpyridinium tetrafluoroborate

    International Nuclear Information System (INIS)

    Highlights: ► (p, ρ, T) data of 1-butyl-4-methylpyridinium tetrafluoroborate are estimated. ► The measurements were carried out with a vibration-tube densimeter. ► The thermomechanical coefficients were calculated. - Abstract: Thermophysical properties, {(p, ρ, T) at T = (283.15 to 393.15) K, pressures up to p = 100 MPa, and viscosity at T = (283.15 to 373.15) K and p = 0.101 MPa}, of 1-butyl-4-methylpyridinium tetrafluoroborate [b4mpy][BF4] are reported. The measurements were carried out with a recently constructed Anton-Paar DMA HPM vibration-tube densimeter and a fully automated SVM 3000 Anton-Paar rotational Stabinger viscometer. The vibration-tube densimeter was calibrated using double-distilled water, methanol, toluene, and aqueous NaCl solutions. An empirical equation of state for fitting of the (p, ρ, T) data of [b4mpy][BF4] has been developed as a function of pressure and temperature to calculate the thermal properties of the ionic liquid (IL), such as isothermal compressibility, isobaric thermal expansibility, differences in isobaric and isochoric heat capacities, thermal pressure coefficient, and internal pressure. Internal pressure and the temperature coefficient of internal pressure data were used to make conclusions on the molecular characteristics of the IL.

  18. Antisickling activity of butyl stearate isolated from Ocimum basilicum (Lamiaceae)

    Institute of Scientific and Technical Information of China (English)

    Dorothe Dinangayi Tshilanda; Pius Tshimankinda Mpiana; Damase Nguwo Vele Onyamboko; Blaise Mavinga Mbala; Koto-te-Nyiwa Ngbolua; Damien Sha Tshibey Tshibangu; Matthieu Kokengo Bokolo; Kalulu Muzele Taba; Teddy Kabeya Kasonga

    2014-01-01

    Objective: To perform phytochemical analyses on the leaves of Ocimum basilicum L. (O. basilicum), to elucidate the structure of isolate and then perform the antisickling activity on the crude extract and on the isolate. Methods:The Emmel test performed on the acidified methanolic extract of this plant was used to evaluate the antisickling activity. The structure characterization of the active compound was performed using chromatographic techniques for the separation and the spectroscopic ones for structure elucidation (1H-NMR, 13C-NMR, COSY, HMBC). Results: The chemical screening on the crude extract revealed the presence of polyphenols (flavonoids, anthocyanins, leucoanthocyanins, tannins, quinones) alkaloids, saponins, triterpenoids and steroids. The obtained extract after evaporation yielded 34.50 g (11.5%) out of 300 g of powdered leaves of O. basilicum. The acidified methanolic extract and butyl stearate showed an interesting antisickling activity. Conclusions:The acidified methanolic extract and butyl stearate from O. basilicum displayed a good antisickling activity. To the best of our knowledge, this is the first time to report the antisickling activity of this compound in this plant. The synthesized compound presented the same spectroscopic characteristics than the natural one and the antisickling activities of its derivatives are understudying.

  19. Production of butyl solvents from lignocellulose: An economic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wright, J D; Daling, R; Sandel, R L; Fitzpatrick, S W

    1986-11-01

    A process is described that produces butyl solvents, butanol, isopropanol, and ethanol from wood or other lignocellulosic feedstock. Two new elements of technology introduced are the processing batch reactor developed at SERI that produces high yields of fermentable sugars (hexoses and pentoses) at the appropriate concentration for the butyl solvents fermentation and a novel method of separating products using liquid-liquid extraction, which reduces the separation energy required to about 30% of energy required in the conventional batch method. Economic analysis suggests that the project is attractive at a feedstock capacity of 400,000 dry MTA or larger (178 million lb/yr solvents). There are, however, uncertainties associated with the project because of the relatively early stage of development of the key elements of the process technology and the sensitivity of the DCFIROR to estimated capital cost. A further conclusion is that the process economics would benefit greatly from reduced capital cost of the fermentation section. This could perhaps be accomplished by developing a continuous fermentation process. Such fermentation technology has been demonstrated on laboratory scale, but as far as is known, has not been developed to pilot scale. 21 refs., 4 figs., 3 tabs.

  20. The plasticizer butyl benzyl phthalate induces genomic changes in rat mammary gland after neonatal/prepubertal exposure

    Directory of Open Access Journals (Sweden)

    Lamartiniere Coral A

    2007-12-01

    Full Text Available Abstract Background Phthalate esters like n-butyl benzyl phthalate (BBP are widely used plasticizers. BBP has shown endocrine-disrupting properties, thus having a potential effect on hormone-sensitive tissues. The aim of this study is to determine the effect of neonatal/prepubertal exposure (post-natal days 2–20 to BBP on maturation parameters and on the morphology, proliferative index and genomic signature of the rat mammary gland at different ages of development (21, 35, 50 and 100 days. Results Here we show that exposure to BBP increased the uterine weight/body weight ratio at 21 days and decreased the body weight at time of vaginal opening. BBP did not induce significant changes on the morphology of the mammary gland, but increased proliferative index in terminal end buds at 35 days and in lobules 1 at several ages. Moreover, BBP had an effect on the genomic profile of the mammary gland mainly at the end of the exposure (21 days, becoming less prominent thereafter. By this age a significant number of genes related to proliferation and differentiation, communication and signal transduction were up-regulated in the glands of the exposed animals. Conclusion These results suggest that BBP has an effect in the gene expression profile of the mammary gland.

  1. Subcellular distribution and uptake mechanism of di-n-butyl phthalate in roots of pumpkin (Cucurbita moschata) seedlings.

    Science.gov (United States)

    Lin, Qingqi; Yang, Xiuhong; Huang, Xiongfei; Wang, Shizhong; Chao, Yuanqing; Qiu, Rongliang

    2016-01-01

    Phthalate acid esters (PAEs) are of particular concern due to their potential environmental risk to human and nonhuman organisms. Although uptake of PAEs by plants has been reported by several researchers, information about the intracellular distribution and uptake mechanisms of PAEs is still lacking. In this study, a series of hydroponic experiments using intact pumpkin (Cucurbita moschata) seedlings was conducted to investigate how di-n-butyl phthalate (DnBP), one of the most frequently identified PAEs in the environment, enters and is distributed in roots. DnBP was transported into subcellular tissues rapidly in the initial uptake period (<12 h). More than 80% of DnBP was detected in the cell walls and organelles, which suggests that DnBP is primarily accumulated in these two fractions due to their high affinity to DnBP. The kinetics of DnBP uptake were fitted well with the Michaelis-Menten equation, suggesting that a carrier-mediated process was involved. The application of 2,4-dinitrophenol and sodium vanadate reduced the uptake of DnBP by 37 and 26%, respectively, while aquaporin inhibitors, silver and glycerol, had no effect on DnBP uptake. These data demonstrated that the uptake of DnBP included a carrier-mediated and energy-dependent process without the participation of aquaporins. PMID:26304812

  2. Studies on Excess Volume, Viscosity, and Speed of Sound of Binary Mixtures of Methyl Benzoate in Ethers at T=(303.15,308.15, and 313.15) K

    OpenAIRE

    Rathnam, M. V.; Ambavadekar, Devappa R.; Nandini, M.

    2013-01-01

    Densities, viscosities, and speed of sound have been determined at T = (303.15, 308.15, and 313.15) K for the binary mixtures of methyl benzoate with tetrahydrofuran, 1,4-dioxane, anisole, and butyl vinyl ether over the entire range of composition. Using these measured values, excess volume VE, deviation in viscosities Δη, excess Gibb’s free energy of activation for viscous flow ΔG*E, and deviation in isentropic compressibility Δks have been calculated. These calculated binary data have been...

  3. Reactive Distillation for Producing n-Butyl Acetate: Experiment and Simulation%Reactive Distillation for Producing n-Butyl Acetate: Experiment and Simulation

    Institute of Scientific and Technical Information of China (English)

    田晖; 黄智贤; 邱挺; 王晓达; 吴燕翔

    2012-01-01

    In this paper, a reactive distillation (RD) column was applied for synthesis n-butyl acetate from n-butanol and acetic acid. The Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetic model and an equilibrium stage model for separation were employed to study the RD process. The results obtained from the equilibrium stage model agreed well with the experiments. The effects of operating variables on the n-butanol conversion and n-butyl acetate purity were further investigated. The optimal column configuration for the production of n-butyl acetate was designed with 5 rectifying stages, 8 reaction stages and 13 stripping stages by the simulation study. According to the simulation results, n-butanol conversion and n-butyl acetate purity all reached greater than 96%.

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

    International Nuclear Information System (INIS)

    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 LiClO4 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 LiClO4, 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

  5. Unprecedented reactions: from epichlorohydrin to epoxyglycidyl substituted divinyl ether and its conversion into epoxyglycidyl propargyl ether

    Science.gov (United States)

    Yao, Yiwu; Li, Zheng; Qiu, Yatao; Bai, Jinhong; Su, Jinyue; Zhang, Dayong; Jiang, Sheng

    2015-09-01

    The reaction of epichlorohydrin with concentrated sodium hydroxide in hexane under phase transfer conditions has surprisingly led to the formation of the symmetrical di(3-epoxyglycidyl-1-propenyl) ether 1 which contains both nucleophilic and electrophilic moieties. When it was reacted with n-butyllithium, intermediate 1 once again surprisingly generated epoxyglycidyl propargyl ether, which was further reacted in situ with a variety of benzaldehydes to furnish the corresponding substituted propargylic alcohols in good yields. While the reaction is operationally simple, it provides a powerful method for the synthesis of the important products from commodity materials such as epichlorohydrin. Moreover, these reactions may have revealed that some fundamental properties of the hydroxide anion in those once thought straightforward reactions are not well understood. A careful analysis of the experimental data suggests that an unprecedented concerted elimination of the epoxyglycidyl ether with sodium hydroxide may be operative and an alpha deprotonation followed by alpha elimination of the di(3-epoxyglycidyl-1-propenyl) ether with alkyllithium may have been involved.

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

    International Nuclear Information System (INIS)

    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 (t0), 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.

  8. Triblock and pentablock terpolymers by sequential base-assisted living cationic copolymerization of functionalized vinyl ethers

    KAUST Repository

    Bouchekif, Hassen

    2015-01-01

    A series of novel, well-defined triblock (PnBVE-b-PCEVE-b-PSiDEGVE) and pentablock (PSiDEGVE-b-PCEVE-b-PnBVE-b-PCEVE-b-PSiDEGVE) terpolymers of n-butyl vinyl ether (nBVE), 2-chloroethyl vinyl ether (CEVE) and tert-butyldimethylsilyl ethylene glycol vinyl ether (SiEGVE) were synthesized by sequential base-assisted living cationic polymerization. The living character of the homopolymerization of the three VE monomers and the crossover reaction resulting in the formation of well-defined block copolymers were investigated in various solvents (toluene, dichloromethane and n-hexane) using either a monofunctional [nBVE-acetic acid adduct (nBEA), CEVE-acetic acid adduct (CEEA) and SiDEGVE-acetic acid adduct (SiDEGEA)] or a difunctional [1,4-cyclohexane-1,4-diyl bis(2-methoxyethyl acetate) (cHDMEA)] initiator. All initiators are structurally equivalent to the dormant species of the corresponding monomers in order to achieve fast initiation. The optimal conditions of polymerization were achieved in n-hexane at -20 °C, in the presence of 1 M AcOEt (base). Good control over the number average molecular weight (Mn) and the polydispersity index (PDI) was obtained only at [Et3Al2Cl3]0 = [Chain-end]0 ≤ 10 mM. 2,6-Di-tert-butylpyridine (DtBP) was used as a non-nucleophilic proton trap to suppress any protonic initiation from moisture (i.e., Et3Al2Cl3·H2O). Well-defined PnBVEn-b-PCEVEp-b-PSiDEGVEq and PSiDEGVEq-b-PCEVEp-b-PnBVEn-b-PCEVEp-b-PSiDEGVEq terpolymers with a high crossover efficiency, no PCEVE-induced physical gelation, and predictable Mn and PDI < 1.15 were synthesized successfully provided that the targeted DPCEVE/DPnBVE ratio (i.e., p/n) did not exceed 2 and 0.2, respectively. The quantitative desilylation of the PSiEGVE by n-Bu4N+F- in THF at 0 °C led to triblock and pentablock terpolymers in which the PCEVE is the central block and the polyalcohol is the outer block. The thermal properties of the synthesized materials were examined by differential scanning

  9. Breast Cancer Genetic and Molecular Subtype Impacts Response to Omega-3 Fatty Acid Ethyl Esters.

    Science.gov (United States)

    Chen, Ching Hui; Fabian, Carol; Hursting, Stephen; deGraffenried, Linda A

    2016-01-01

    Epidemiological studies have correlated frequent omega-3 (n-3) fatty acid consumption with a lower risk for breast cancer; however, recent prospective studies have been less conclusive. Efforts in the preventive setting have focused on the use of n-3 fatty acids, and the pharmaceutical ethyl esters (EE) of these natural compounds, for high-risk patient populations. Limited understanding of specific mechanisms by which these agents function has hampered identification of the cancer subtype(s) that would gain the greatest therapeutic benefit. In this study, we investigated the in vitro effects of n-3 EEs in four distinct breast cancer subtypes and explored how they affect not only breast cancer cell survival but also modulate the nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB) and peroxisome proliferator-activated receptor gamma signaling pathways. Similar to the high variance in response observed in human studies, we found that the effectiveness of n-3 EEs depends on the molecular characteristics of the MCF-7, CAMA-1, MDA-MB-231, and SKBR3 breast cancer cell lines and is closely associated with the suppression of NF-κB. These data strongly suggest that the use of n-3 fatty acids and their pharmaceutical ether esters in the prevention and therapeutic setting should be guided by specific tumor characteristics. PMID:27367296

  10. 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...

  11. 阻燃剂三嗪三苯基次膦酸叔丁酯的合成及应用%Synthesis and Application of Flame Retardant 2-4-6-three(O-tertiary butyl-phenyl phosphinic acyl)-1,3,5-triazine

    Institute of Scientific and Technical Information of China (English)

    李果; 胡新利; 王彦林

    2015-01-01

    A novel flame retardant,2,4,6-three(O-tertiary butyl-phenyl phosphinic acyl)-1,3,5-triazine was synthesized from cyanuric chloride and phenyl phosphonic acid two tert-butyl ester. Effects of reaction time,reaction temperature,phenyl phosphonic acid two tert-butyl ester dropping speed and material proportion on yield of product were investigated. The product reached 90.6%under the optimal conditions of r(phenyl phosphonic acid two tert-butyl ester)∶r(cyanuric chloride)=3.4,dropping phenyl phosphonic acid two tert-butyl ester at twice,then keeping the reaction going at 100℃for 5 h. The target compound was characterized by means of FTIR,1H NMR,TG–DTA analysis and limiting oxygen index technique. The results show that the product have the high flame retardance,good compatibility with PE and have high fire retardance when mix with MCA and MPP.%以三聚氯氰和苯基次膦酸二叔丁酯为原料,合成新型阻燃剂三嗪三苯基次膦酸叔丁酯2,4,6-三(O-叔丁基–苯基次膦酰基)-1,3,5-三嗪化合物。讨论了反应时间、反应温度、原料配比等对合成反应的影响。其最佳反应条件为:三聚氯氰与苯基次膦酸二叔丁酯的物质的量之比为1∶3.4,分两次滴加苯基次膦酸二叔丁酯,在100℃反应5 h,收率为90.6%。采用傅里叶变换红外光谱、核磁共振、差热分析及极限氧指数等表征了产品的结构及阻燃应用性能。研究表明,该化合物对PE阻燃效能高,相容性好,且与MCA,MPP复配有很好的协同阻燃效果。

  12. Affinity labelling enzymes with esters of aromatic sulfonic acids

    Science.gov (United States)

    Wong, Show-Chu; Shaw, Elliott

    1977-01-01

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

  13. 76 FR 46796 - Butylate; Registration Review Proposed Decision; Notice of Availability

    Science.gov (United States)

    2011-08-03

    ... Register on July 28, 2010 (75 FR 44240; FRL-8835-2). For the remaining butylate product registrations... published in the Federal Register on March 23, 2011 (76 FR 16147, FRL-8867-8). Due to the cancellation...-use registrant, Arysta Lifescience North America, LLC, to voluntarily cancel the last butylate...

  14. Sources of propylene glycol and glycol ethers in air at home.

    Science.gov (United States)

    Choi, Hyunok; Schmidbauer, Norbert; Spengler, John; Bornehag, Carl-Gustaf

    2010-12-01

    Propylene glycol and glycol ether (PGE) in indoor air have recently been associated with asthma and allergies as well as sensitization in children. In this follow-up report, sources of the PGEs in indoor air were investigated in 390 homes of pre-school age children in Sweden. Professional building inspectors examined each home for water damages, mold odour, building's structural characteristics, indoor temperature, absolute humidity and air exchange rate. They also collected air and dust samples. The samples were analyzed for four groups of volatile organic compounds (VOCs) and semi-VOCs (SVOCs), including summed concentrations of 16 PGEs, 8 terpene hydrocarbons, 2 Texanols, and the phthalates n-butyl benzyl phthalate (BBzP), and di(2-ethylhexyl)phthalate (DEHP). Home cleaning with water and mop ≥ once/month, repainting ≥ one room prior to or following the child's birth, and "newest" surface material in the child's bedroom explained largest portion of total variability in PGE concentrations. High excess indoor humidity (g/m³) additionally contributed to a sustained PGE levels in indoor air far beyond several months following the paint application. No behavioral or building structural factors, except for water-based cleaning, predicted an elevated terpene level in air. No significant predictor of Texanols emerged from our analysis. Overall disparate sources and low correlations among the PGEs, terpenes, Texanols, and the phthalates further confirm the lack of confounding in the analysis reporting the associations of the PGE and the diagnoses of asthma, rhinitis, and eczema, respectively. PMID:21318004

  15. NF EN 14103. July 2003. Fatty compounds derived products. Fatty acids methylic esters (FAME). Determination of the ester and methylic ester content of linoleic acid; NF EN 14103. Juillet 2003. Produits derives des corps gras. Esters methyliques d'acides gras (EMAG). Determination de la teneur en ester et en ester methylique de l'acide linolenique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    This European standard aims at determining the ester and methylic ester content of fatty acids methylic esters (FAME) used as pure bio-fuels or as constituent of a heating or diesel fuel. This method allows also to determine the methylic ester content of linoleic acid. It allows to verify that the ester content of FAMEs is greater than 90% (m/m) and that the linoleic acid content is comprised between 1% (m/m) and 15% (m/m). The method is applicable to FAMEs with methylic ester contents comprised between C14 and C24. (J.S.)

  16. Long-lived testosterone esters in the rat.

    OpenAIRE

    Borg, W; Shackleton, C. H.; Pahuja, S L; Hochberg, R B

    1995-01-01

    Over the past decade it has become increasingly clear that steroid hormones are enzymatically esterified with fatty acids. These steroidal esters are the natural analogs of synthetic esters that are used therapeutically. One such family of pharmacological steroids is the synthetic alkyl esters of testosterone, androgens with great hormonal potency. We have investigated whether testosterone esters exist naturally by using the rat as a model. Most tissues of male rats, including blood, have ver...

  17. Recovering/recycling of butyl and halogenated butyl rubber via ionizing radiation; Recuperacao/reciclagem de compostos de borrachas butilica e halobutilica por meio de radiacao ionizante

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Sandra Regina Scagliusi

    2013-07-01

    Polymeric materials (plastics and rubbers) attain a continuous and raising proportion of urban and industrial scraps discarded in landfills; their impact on environment are more and more concerning. The implementation of new technologies in order to reduce impacts of plastic waste on the environment, at an effective cost, proved to be a great problem, due to inherent complexity for polymers re-using. Ionizing radiation is capable to modify structure and properties of polymeric material. Butyl and halobutyl rubbers have been used within a comprehensive scale, applications such as tires spare parts and diverse artifacts. The major high energy photon effect, as gamma-rays in butyl and halo butyl rubbers consists in free-radicals generation along changes in mechanical properties.This work aims to the development of controlled degradation processes (devulcanization) of butyl and halo butyl (chlorine and bromine) rubbers, in order to characterize their availability for transformation and modification of properties. Experimental results obtained showed that butyl and halobutyl rubbers,irradiated at 25 kGy and further sheared, are able to be used as an initial point for mixtures with pristine. (author)

  18. Effect of various concentrations of butylated hydroxyanisole and butylated hydroxytoluene on freezing capacity of Turkman stallion sperm.

    Science.gov (United States)

    Seifi-Jamadi, Afshin; Kohram, Hamid; Zareh-Shahne, Ahmad; Dehghanizadeh, Parvaneh; Ahmad, Ejaz

    2016-07-01

    The present study aimed to determine the effect of different concentrations of butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) on post-thaw stallion sperm quality. The ejaculates collected from four healthy mature Turkmen stallions were pooled and divided into eight aliquots. The samples were diluted with extenders containing different concentrations (0.5, 1 or 2mM/mL) of BHA or BHT. The positive control (PC) samples were diluted with extender containing 0.5% ethanol (v/v) whereas; the negative control (NC) samples were diluted with basic extender only. Semen samples were frozen according to a standard protocol. After thawing of samples, sperm motility, viability, membrane integrity, total abnormality and lipid peroxidation were assessed. The greatest (P<0.05) values for total sperm motility, viability and plasma membrane functionality and least values for malonedialdehyde (MDA) concentration were observed in samples supplemented either with 1mM BHT or 2mM BHA. However, the progressive motility was greater (P<0.05) only in samples treated with 2mM BHA. In conclusion, the use of 1mM BHT or 2mM BHA in extender improves the freezing capacity of stallion sperm by reducing oxidative stress during freeze-thaw process. PMID:27112036

  19. Synthesis of Highly Porous Poly(tert-butyl acrylate)-b-polysulfone-b-poly(tert-butyl acrylate) Asymmetric Membranes

    KAUST Repository

    Xie, Yihui

    2016-03-24

    For the first time, self-assembly and non-solvent induced phase separation was applied to polysulfone-based linear block copolymers, reaching mechanical stability much higher than other block copolymers membranes used in this method, which were mainly based on polystyrene blocks. Poly(tert-butyl acrylate)-b-polysulfone-b-poly(tert-butyl acrylate) (PtBA30k-b-PSU14k-b-PtBA30k) with a low polydispersity of 1.4 was synthesized by combining step-growth condensation and RAFT polymerization. Various advanced electron microscopies revealed that PtBA30k-b-PSU14k-b-PtBA30k assembles into worm-like cylindrical micelles in DMAc and adopts a “flower-like” arrangement with the PSU central block forming the shell. Computational modeling described the mechanism of micelle formation and morphological transition. Asymmetric nanostructured membranes were obtained with a highly porous interconnected skin layer and a sublayer with finger-like macrovoids. Ultrafiltration tests confirmed a water permeance of 555 L m-2 h-1 bar-1 with molecular weight cut-off of 28 kg/mol. PtBA segments on the membrane surface were then hydrolyzed and complexed with metals, leading to cross-linking and enhancement of antibacterial capability.

  20. Levels of synthetic antioxidants (ethoxyquin, butylated hydroxytoluene and butylated hydroxyanisole) in fish feed and commercially farmed fish.

    Science.gov (United States)

    Lundebye, A-K; Hove, H; Måge, A; Bohne, V J B; Hamre, K

    2010-12-01

    Several synthetic antioxidants are authorized for use as feed additives in the European Union. Ethoxyquin (EQ) and butylated hydroxytoluene (BHT) are generally added to fish meal and fish oil, respectively, to limit lipid oxidation. The study was conducted to examine the concentrations of EQ, BHT and butylated hydroxyanisole (BHA) in several commercially important species of farmed fish, namely Atlantic salmon, halibut and cod and rainbow trout, as well as concentrations in fish feed. The highest levels of BHT, EQ and BHA were found in farmed Atlantic salmon fillets, and were 7.60, 0.17 and 0.07 mg kg(-1), respectively. The lowest concentrations of the synthetic antioxidants found were in cod. The concentration of the oxidation product ethoxyquin dimer (EQDM) was more than ten-fold higher than the concentration of parent EQ in Atlantic salmon halibut and rainbow trout, whereas this dimer was not detected in cod fillets. The theoretical consumer exposure to the synthetic antioxidants EQ, BHA and BHT from the consumption of farmed fish was calculated. The contribution of EQ from a single portion (300 g) of skinned fillets of the different species of farmed fish would contribute at most 15% of the acceptable daily intake (ADI) for a 60 kg adult. The consumption of farmed fish would not contribute measurably to the intake of BHA; however, a 300 g portion of farmed Atlantic salmon would contribute up to 75% of the ADI for BHT. PMID:20931417

  1. Sucrose esters from Physalis peruviana calyces with anti-inflammatory activity.

    Science.gov (United States)

    Franco, Luis A; Ocampo, Yanet C; Gómez, Harold A; De la Puerta, Rocío; Espartero, José L; Ospina, Luis F

    2014-11-01

    Physalis peruviana is a native plant from the South American Andes and is widely used in traditional Colombian medicine of as an anti-inflammatory medicinal plant, specifically the leaves, calyces, and small stems in poultice form. Previous studies performed by our group on P. peruviana calyces showed potent anti-inflammatory activity in an enriched fraction obtained from an ether total extract. The objective of the present study was to obtain and elucidate the active compounds from this fraction and evaluate their anti-inflammatory activity in vivo and in vitro. The enriched fraction of P. peruviana was purified by several chromatographic methods to obtain an inseparable mixture of two new sucrose esters named peruviose A (1) and peruviose B (2). Structures of the new compounds were elucidated using spectroscopic methods and chemical transformations. The anti-inflammatory activity of the peruvioses mixture was evaluated using λ-carrageenan-induced paw edema in rats and lipopolysaccharide-activated peritoneal macrophages. Results showed that the peruvioses did not produce side effects on the liver and kidneys and significantly attenuated the inflammation induced by λ-carrageenan in a dosage-dependent manner, probably due to an inhibition of nitric oxide and prostaglandin E2, which was demonstrated in vitro. To our knowledge, this is the first report of the presence of sucrose esters in P. peruviana that showed a potent anti-inflammatory effect. These results suggest the potential of sucrose esters from the Physalis genus as a novel natural alternative to treat inflammatory diseases. PMID:25338213

  2. Effect of Concentration of Catalyst (BF3-Diethyl Etherate on Synthesis of Polyester From Palm Fatty Acid Distillate (PFAD

    Directory of Open Access Journals (Sweden)

    Renita Manurung

    2013-10-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE Palm Fatty Acid Distillate (PFAD can be used as raw material for synthesis polyester. The aim of this research is to synthesis of polyester and to determine the effect of concentration of catalyst on polymerization methyl ester PFAD. The esterification stage was done at temperature 70oC, reaction time 120 minute, reactant ratio 1:8 (PFAD: methanol, concentration of catalyst (H2SO4 1% (w/w PFAD; polymerization stage was done at temperature 126-132°C, polymerization reaction time 4 hours; variation of concentration of catalyst (BF3-diethyl etherate 0%, 6.9%, 9.2%, 11.5% (w/w methyl ester; and polyesterification stage was done at temperature 175-200 oC, reactant ratios (w/w 1:1 (polymerized ME : ethylene glycol, reaction time 4 hours and all of stage was stirred at 150 rpm. The results showed, in the esterification stage was obtained methyl ester with iodine value 77.29 g I2/100 g, viscosity 6.90 cP, density 859.91 kg/m3 and analysis by using GC-MS showed that the purity of methyl ester was 82.23% and molecular weight 267.97 g/mol. Decreasing in iodine value from 77.29 I2 g/100 g to 74.97-59.99 g I2/100 g indicated that the polymerization process had taken place. In polyesterification stage was obtained light brown colored

  3. Acrylic Acid and Esters Will Be Oversupply

    Institute of Scientific and Technical Information of China (English)

    Zheng Chengwang

    2007-01-01

    @@ Drastic capacity growth The production capacity of acrylic acid in China has grown drastically in recent years. With the completion of the 80 thousand t/a acrylic acid and 130 thous and t/a acrylic ester project in Shenyang Paraffin Chemical Industrial Co., Ltd., (CCR2006,No. 31) the capacity of acrylic acid in China has reached 882 thousand t/a.

  4. Correlation and prediction of mixing thermodynamic properties of ester-containing systems: Ester + alkane and ester + ester binary systems and the ternary dodecane + ethyl pentanoate + ethyl ethanoate

    International Nuclear Information System (INIS)

    Highlights: ► Excess enthalpies and volumes were measured for ester–ester–alkane. ► Mixing behaviour for ester–ester, ester–alkane and ester–ester–alkane are analyzed. ► Correlations with a new polynomial model reproduce well the mixing properties. ► UNIFAC predictions for hE result acceptable excluding the ester–ester mixtures. - Abstract: Excess thermodynamic properties VmE and HmE, have been measured for the ternary mixture dodecane + ethyl pentanoate + ethyl ethanoate and for the corresponding binaries dodecane + ethyl pentanoate, dodecane + ethyl ethanoate, ethyl pentanoate + ethyl ethanoate at 298.15 K. All mixtures show endothermic and expansive effects. Experimental results are correlated with a suitable equation whose final form for the excess ternary quantity ME contains the particular contributions of the three binaries (i–j) and a last term corresponding to the ternary, all of them obtained considering fourth-order interactions. The fit goodness for all mixtures is good and comparable to others equations taken from the literature. In this work the dissolution model for the binaries and ternary is analyzed with a special attention to ester–ester binaries whose behaviour is discussed. The application of the UNIFAC group contribution model to estimate the HmE yields acceptable results for the binaries (with the exception of ester–ester) and for the ternary mixture.

  5. Technetium and rhenium tracers with metabolizable ester functions

    International Nuclear Information System (INIS)

    Re-DMSA (dimercaptosuccinic acid) ester complexes were prepored by ligand exchange reactions. To determine whether the ester band in Re-DMSA ester complexes is susceptible to cleavage by esterases, incubation experiments with tissue homogenates and plasma were carried out. (BBR)

  6. 40 CFR 721.3085 - Brominated phthalate ester.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Brominated phthalate ester. 721.3085... Substances § 721.3085 Brominated phthalate ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as brominated phthalate ester (PMN P-90-581)...

  7. 21 CFR 175.210 - Acrylate ester copolymer coating.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Acrylate ester copolymer coating. 175.210 Section... COATINGS Substances for Use as Components of Coatings § 175.210 Acrylate ester copolymer coating. Acrylate ester copolymer coating may safely be used as a food-contact surface of articles intended for...

  8. Determination of Mass Spectrometric Sensitivity of Different Metalloporphyrin Esters Relative to Porphyrin Ester

    DEFF Research Database (Denmark)

    Larsen, Elfinn; Egsgaard, Helge; Møller, J.;

    1977-01-01

    Quantitative determination of metalloporphyrin contamination in preparations of biologically important porphyrins was achieved mass spectrometrically by application of the integrated ion current technique. For this purpose, the relative molecular ion sensitivities of the contaminating metal...... complexes were determined from the ratios of the integrated molecular ion currents of a series of calibration samples containing a porphyrin ester and one of its metal complexes in known molar ratio. Complexes formed with divalent ions of Cu, Zn, Fe, Co and Ni of copro- as well as uro......-prophyrin permethylester were all found to have the same molecular ion sensitivities as their metal-free porphyrin ester. The relative metalloporphyrin ester content in a sample of porphyrin ester was thus obtained directly as the integrated ion current ratios of the normalized molecular ions. The preparation of...

  9. Ester Tuiksoo - Eesti esimene naissoost põllumajandusminister / Ester Tuiksoo ; interv. Toomas Verrev

    Index Scriptorium Estoniae

    Tuiksoo, Ester, 1965-

    2007-01-01

    Ametist lahkuv põllumajandusminister Ester Tuiksoo räägib saadud juhtimiskogemusest, Euroopa Liidu ühise põllumajanduspoliitika juurutamisest, rahvuskala valimisest, Rahvaliidu käekäigust parlamendivalimistel

  10. 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...

  11. Synthesis and Biophysical Characterization of Chlorambucil Anticancer Ether Lipid Prodrugs

    DEFF Research Database (Denmark)

    Pedersen, Palle Jacob; Christensen, Mikkel Stochkendahl; Ruysschaert, Tristan;

    2009-01-01

    The synthesis and biophysical characterization of four prodrug ether phospholipid conjugates are described. The lipids are prepared from the anticancer drug chlorambucil and have C16 and C18 ether chains with phosphatidylcholine or phosphatidylglycerol headgroups. All four prodrugs have the abili...

  12. 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

    1997-01-01

    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 nanc

  13. Antioxidant properties of modified rutin esters by DPPH, reducing power, iron chelation and human low density lipoprotein assays

    DEFF Research Database (Denmark)

    Lue, Bena-Marie; Nielsen, Nina Skall; Jacobsen, Charlotte;

    2010-01-01

    moieties. Herein, two derivatives of rutin (possessing C12:0 or C16:0 acyl groups) were assessed for their antioxidant properties, and compared with their parent compound, rutin and with butylated hydroxytoluene (BHT). While all compounds exhibited relatively strong radical scavenging abilities, modified...... rutin compounds exhibited decreased reducing power and metal chelating abilities as compared to rutin. Conversely, investigations on the oxidation of human low density lipoprotein (LDL) revealed that rutin laurate was most effective in inhibiting oxidation by prolonging LDL lag time for an in vitro...... system. With regards to in vivo considerations, a pre-treatment step confirmed that the ester bond linking rutin and acyl moieties was most susceptible to hydrolysis by digestive enzymes, while rutin itself was not degraded. Thus, acylation of rutin with medium or long chain fatty acids may result in...

  14. Half esters and coating compositions comprising reactions products of half esters and polyepoxides

    OpenAIRE

    Blaauw, R; Mulder, W J; Koelewijn, R.; Boswinkel, G.

    2006-01-01

    The present invention relates to half esters based on dicarboxylic acid derivatives and dimer fatty diols, wherein the dimer fatty dio ls are based on dimerised and/or trimerised and/or oligomerised unsaturated fatty acids. The present invention further relates to resin compositions based on the half ester and an polyepoxide. The resin composition can be used in high solids coatings, inks, adhesives, wall covering products, flooring products and plastic products

  15. Expanding the modular ester fermentative pathways for combinatorial biosynthesis of esters from volatile organic acids.

    Science.gov (United States)

    Layton, Donovan S; Trinh, Cong T

    2016-08-01

    Volatile organic acids are byproducts of fermentative metabolism, for example, anaerobic digestion of lignocellulosic biomass or organic wastes, and are often times undesired inhibiting cell growth and reducing directed formation of the desired products. Here, we devised a general framework for upgrading these volatile organic acids to high-value esters that can be used as flavors, fragrances, solvents, and biofuels. This framework employs the acid-to-ester modules, consisting of an AAT (alcohol acyltransferase) plus ACT (acyl CoA transferase) submodule and an alcohol submodule, for co-fermentation of sugars and organic acids to acyl CoAs and alcohols to form a combinatorial library of esters. By assembling these modules with the engineered Escherichia coli modular chassis cell, we developed microbial manufacturing platforms to perform the following functions: (i) rapid in vivo screening of novel AATs for their catalytic activities; (ii) expanding combinatorial biosynthesis of unique fermentative esters; and (iii) upgrading volatile organic acids to esters using single or mixed cell cultures. To demonstrate this framework, we screened for a set of five unique and divergent AATs from multiple species, and were able to determine their novel activities as well as produce a library of 12 out of the 13 expected esters from co-fermentation of sugars and (C2-C6) volatile organic acids. We envision the developed framework to be valuable for in vivo characterization of a repertoire of not-well-characterized natural AATs, expanding the combinatorial biosynthesis of fermentative esters, and upgrading volatile organic acids to high-value esters. Biotechnol. Bioeng. 2016;113: 1764-1776. © 2016 Wiley Periodicals, Inc. PMID:26853081

  16. Synthesis of 11C labelled methyl esters: transesterification of enol esters versus BF3 catalysed esterification-a comparative study

    International Nuclear Information System (INIS)

    C-11 labelled methyl esters have been synthesized via the transesterification of enol esters in the presence of C-11 methanol and 1,3 dichlorodibutylstannoxane as catalyst. This method leaves functional groups intact and allows access to a wider variety of C-11 labelled methyl esters compared to the BF3 catalysed ester formation, which uses carboxylic acids and C-11 methanol as starting materials

  17. Effects and toxicity of phthalate esters to hemocytes of giant freshwater prawn, Macrobrachium rosenbergii

    International Nuclear Information System (INIS)

    Phthalate esters (PAEs) have been considered as environmental pollutants and have been subject to control in the United States of America and Japan. The aim of this study was to investigate the effects and toxicity of eight PAEs to hemocytes and the defense functions of giant freshwater prawn (Macrobrachium rosenbergii), including hemocytic adhesion, pseudopodia formation, phenoloxidase (PO) activity, and superoxide anion (O2-) production, by means of in vitro exposure experiments. After hemocytes were treated separately with eight PAEs at concentrations of 100 μg/ml, the results showed that two PAEs (dipropyl phthalate, DPrP and diethyl phthalate, DEP) increased cells with pseudopodia formation, but decreased adhesive cells; reduction in the percentages of both pseudopodia formation and adhesive cells were detected in the dihexyl phthalate (DHP) and diphenyl phthalate (DPP) experiment groups; and di-(2-ethyl hexyl) phthalate (DEHP) decreased pseudopodia formation, but did not affect the adhesion. In addition, both PO activity and O2- production were decreased after hemocytes were treated with five PAEs (benzyl butyl phthalate (BBP), di-n-butyl phthalate (DBP), DEP, DHP and DPrP), respectively. At the same time, microscopy showed that both DPrP and DHP altered morphology of the cell nucleus and led to the presence of vacuoles in cytosol of hemocytes. Using the annexin assay, and after analysis of DNA fragmentation and transmission electron microscopy (TEM), it was found that hemocytes exposed to DHP and DPrP for more than 10 min would primarily die via apoptosis, the fatality correlates with increasing treatment time; and hemocytes treated with either BBP, dicyclohexyl phthalate (DCP), DEP or DPP would primarily die via necrosis. According to these results, we suggest that all eight PAEs examined could damage hemocytes and further influence the defense mechanism of prawns. This study reveals an important precaution for prawn cultivation

  18. Isobaric (vapor + liquid) equilibrium data for the binary system methanol + 2-butyl alcohol and the quaternary system methyl acetate + methanol + 2-butyl alcohol + 2-butyl acetate at P = 101.33 kPa

    International Nuclear Information System (INIS)

    Highlights: • VLE data for methanol + 2-butyl alcohol were determined. • VLE data for methyl acetate + methanol + 2-butyl alcohol + SBAC were determined. • The binary interaction parameters were obtained based on the binary VLE data. • The data of quaternary system have been predicted. • Both Wilson and NRTL models are suitable to describe the VLE of quaternary system. - Abstract: In this paper, isobaric (vapor + liquid) equilibrium (VLE) data for the binary system methanol + 2-butyl alcohol and the quaternary system methyl acetate + methanol + 2-butyl alcohol + 2-butyl acetate were determined at P = 101.33 kPa in a modified Rose still. The binary VLE data were found to be thermodynamic consistency by the Herrington method. The VLE data for the binary system were correlated by the Wilson and NRTL equations respectively, which were used to predict the VLE data of the quaternary system. The results showed that the Wilson and NRTL models matched well with the (vapor + liquid) phase equilibrium data. The deviations for the vapor-phase compositions and the equilibrium temperatures are reasonably small and the models are both suitable for these systems

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

    NARCIS (Netherlands)

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

    2016-01-01

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

  20. Interactions between water and 1-butyl-1-methylpyrrolidinium ionic liquids.

    Science.gov (United States)

    Fadeeva, Tatiana A; Husson, Pascale; DeVine, Jessalyn A; Costa Gomes, Margarida F; Greenbaum, Steven G; Castner, Edward W

    2015-08-14

    We report experimental results on the diffusivity of water in two ionic liquids obtained using the pulsed-gradient spin-echo NMR method. Both ionic liquids have the same cation, 1-butyl-1-methylpyrrolidinium, but different trifluoromethyl-containing anions. One has a strongly hydrophobic anion, bis(trifluoromethylsulfonyl)amide, while the second has a hydrophilic anion, trifluoromethylsulfonate. Transport of water in these ionic liquids is much faster than would be predicted from hydrodynamic laws, indicating that the neutral water molecules experience a very different friction than the anions and cations at the molecular level. Temperature-dependent viscosities, conductivities, and densities are reported as a function of water concentration to further analyze the properties of the ionic liquid-water mixtures. These results on the properties of water in ionic liquids should be of interest to researchers in diverse areas ranging from separations, solubilizing biomass and energy technologies. PMID:26277141

  1. Biological fate of butylated hydroxytoluene (BHT) in rats, (3)

    International Nuclear Information System (INIS)

    Butylated hydroxytoluene (BHT) is the chemical widely used not only as the antioxidant for food additives but also as that for containers. 14C-BHT was administered orally to rats, and the subcellular distribution and the change of existence mode in course of time in kidneys were investigated, also the separation and identification of the metabolites in urine were tested. Radioactivity was determined with a liquid scintillation counter. Subcellular fractions were separated by the gel-filtration with Sephadex, and thin layer autoradiography was performed, and radioactive parts were confirmed. The radioactivity in each fraction of the reference group showed the highest 6 hours after the administration, and then it decreased rapidly, but the radioactivity in microsome fraction was the highest at 12 hours after the administration. Only BHT acids was identified out of the metabolites in urine by the thin layer autoradiography, and further investigation will be made about other metabolites. (Kobatake, H.)

  2. Microemulsion polymerization of butyl acrylate irradiated by γ-ray

    International Nuclear Information System (INIS)

    Radiation polymerization of butyl acrylate was carried out in microemulsion with high monomer and low emulsifier content. The rate of polymerization shows three intervals--the increasing period, the plateau period and the decreasing period for most cases. The length of nucleation period is independent of monomer content and temperature, and becomes longer with the increase of dose rate and the decrease of emulsifier content. The length of Rp plateau region increases with the increase of monomer and emulsifier content and with the decrease of dose rate. By studying the kinetics, the following formula were derived: Rp ∝ [M]0.93D1.27 [E]-1.07; Mn ∝ [M]0.65D0.28 [E]-1.66. (author)

  3. Interactions between water and 1-butyl-1-methylpyrrolidinium ionic liquids

    Energy Technology Data Exchange (ETDEWEB)

    Fadeeva, Tatiana A.; DeVine, Jessalyn A.; Castner, Edward W., E-mail: ed.castner@rutgers.edu [Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854 (United States); Husson, Pascale [CNRS, UMR 6296, Institut de Chimie de Clermont-Ferrand, BP 80026, F-63171 Aubière (France); Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, F-63000 Clermont-Ferrand (France); Costa Gomes, Margarida F. [CNRS, UMR 6296, Institut de Chimie de Clermont-Ferrand, BP 80026, F-63171 Aubière (France); Greenbaum, Steven G. [Department of Physics and Astronomy, Hunter College, CUNY, New York, New York 10065 (United States)

    2015-08-14

    We report experimental results on the diffusivity of water in two ionic liquids obtained using the pulsed-gradient spin-echo NMR method. Both ionic liquids have the same cation, 1-butyl-1-methylpyrrolidinium, but different trifluoromethyl-containing anions. One has a strongly hydrophobic anion, bis(trifluoromethylsulfonyl)amide, while the second has a hydrophilic anion, trifluoromethylsulfonate. Transport of water in these ionic liquids is much faster than would be predicted from hydrodynamic laws, indicating that the neutral water molecules experience a very different friction than the anions and cations at the molecular level. Temperature-dependent viscosities, conductivities, and densities are reported as a function of water concentration to further analyze the properties of the ionic liquid-water mixtures. These results on the properties of water in ionic liquids should be of interest to researchers in diverse areas ranging from separations, solubilizing biomass and energy technologies.

  4. Interactions between water and 1-butyl-1-methylpyrrolidinium ionic liquids

    International Nuclear Information System (INIS)

    We report experimental results on the diffusivity of water in two ionic liquids obtained using the pulsed-gradient spin-echo NMR method. Both ionic liquids have the same cation, 1-butyl-1-methylpyrrolidinium, but different trifluoromethyl-containing anions. One has a strongly hydrophobic anion, bis(trifluoromethylsulfonyl)amide, while the second has a hydrophilic anion, trifluoromethylsulfonate. Transport of water in these ionic liquids is much faster than would be predicted from hydrodynamic laws, indicating that the neutral water molecules experience a very different friction than the anions and cations at the molecular level. Temperature-dependent viscosities, conductivities, and densities are reported as a function of water concentration to further analyze the properties of the ionic liquid-water mixtures. These results on the properties of water in ionic liquids should be of interest to researchers in diverse areas ranging from separations, solubilizing biomass and energy technologies

  5. Levels of phthalate esters in settled house dust from urban dwellings with young children in Nanjing, China

    Science.gov (United States)

    Zhang, Qi; Lu, Xiao-Mei; Zhang, Xiao-Ling; Sun, Yong-Gang; Zhu, Dong-Mei; Wang, Bing-Ling; Zhao, Ren-Zheng; Zhang, Zheng-Dong

    2013-04-01

    To investigate the levels and possible determinants of phthalate esters (PEs) in settled house dust from urban dwellings with young children, dust was collected from 215 urban houses in Nanjing, China, and 145 outdoor settled dust samples were collected nearby. Six PEs were measured by gas chromatography/mass spectrometry. All PEs were detected in the dust from approximately 90% of the houses, with the exception of dioctyl phthalate (DOP), which had only a 59% detection rate. Di-2-ethylhexyl phthalate (DEHP) and di-n-butyl phthalate (DBP) were the most abundant PEs, with geometric means of 110 and 16.4 μg g-1, respectively, and maximal concentrations 9950 and 2150 μg g-1. Factor analysis showed that DBP, DEHP and benzyl butyl phthalate (BBP) might come from the same source and were significantly influenced by the use of solid-wood floor wax. High BBP, DEHP, DOP and total PE levels were associated with indices of dampness, and high DOP was associated with humidifier use. In conclusion, six PEs are ubiquitous in urban settled house dust in Nanjing, China, and both plastic materials and cosmetic and personal care products are important sources. Flooring material, dampness and humidifier use potentially influence house dust PE levels.

  6. Ethylated Urea - Ether - Modified Urea - Formaldehyde Resins,

    Directory of Open Access Journals (Sweden)

    Mathew Obichukwu EDOGA

    2006-07-01

    Full Text Available First, phenol - formaldehyde (PF and urea - formaldehyde (UFII resins were separately conventionally prepared in our laboratory. Also, UF resin synthesized from the acid modified synthesis procedure was synthesized in a purely acid medium of pH 1.0, FU molar ratio of 1.0 and at 50oC (one-stage acid modified-synthesis procedure. Subsequently, the UF resin II was modified during synthesis by incorporating ethylated urea-ether (EUER (i.e. UFIII and glycerol (GLYC (i.e. UFV cured with and without acid curing agent. The structural and physicochemical analyses of the various resin samples were carried out.The results showed that the unmodified UF resin (UF II synthesized in acid medium of pH 1.0, F/U molar ratio 1.0, and at 50oC, cured in absence of acid curing catalyst, showed features in their spectra which are consistent with a tri-, and/or tetra-substituted urea in the reaction to give a 3 - dimensional network cured UF resin. Modification of the UF resin(UF II with ethylated urea-ether and glycerol to produce UF resins III and respectively V prominently increased the absorbance of methylene and ether groups in the spectra which are consistent with increased hydrophobicity and improved hydrolytic stability. For the conventional UF resin (UF I, the only clear distinction between spectra for the UF resin II and UF resins (III/V is the presence of diminished peaks for methylene groups at 2.2 ppm. The relationship between the logarithmic viscosity of cured PF resin with time showed continuos dependence of viscosity with time during cure up to 70 minutes. Similar trends were shown by UF resins (III/V, cured in absence of acid catalyst. In contrast, the conventional UF resins I and UF IV (i.e. UF II cured with NH4CL showed abrupt discontinuity in viscosity with time just after about 20 minutes of cure.

  7. 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)

  8. Polymeric 32-channel arrayed waveguide grating multiplexer using fluorinated poly (ether ether ketone)

    Institute of Scientific and Technical Information of China (English)

    Fei Wang(王菲); Wei Sun(孙伟); Aize Li(李艾泽); Maobin Yi(衣茂斌); Zhenhua Jiang(姜振华); Daming Zhang(张大明)

    2004-01-01

    In wavelength division multiplexing (WDM) systems, an arrayed waveguide grating (AWG) multiplexer is a key component. A polymeric AWG multiplexer has recently attracted much attention due to its low cost processing and a potential of integration with other devices. Fluorinated poly (ether ether ketone)(FPEEK) is excellent material for fabrication of optical waveguides due to its low absorption loss at 1.55-μm wavelength and high thermal stability. A 32-channel AWG multiplexer has been designed based on the grating diffraction theory and fabricated using newly synthesized FPEEK. During the fabrication process of the Polymer/Si AWG device, spin coating, vaporizing, photolithographic patterning and reactive ion etching (RIE) are used. The AWG multiplexer measurement system is based on a tunable semiconductor laser, infrared camera and a Peltier-type heater. The device exhibits a wavelength channel spacing of 0.8nm and a center wavelength of 1548 nm in the room temperature.

  9. 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.

  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. PMID:26954085

  11. Effects of spinneret structure on poly-ether-ether-ketone fibers by screw extrusion

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xin-ying; YI Xiao-su; XU Zhong-bin; XU Ya-hong

    2005-01-01

    According to the characters of poly-ether-ether-ketone (PEEK) plastic, the spinnerets with three kinds of different structure were designed. The effects of spinneret structure on the melt spinning conditions, melt flow instability of the screw extrusion, and the performance of PEEK fibers were studied. The results show that the appropriate screw extrusion temperature is 370 -385℃. The PEEK fibers extruded using the spinnerets with L/D= 6,8 holes and 0.5 mm in diameter have better performances. The performances of PEEK fibers are related to the diameter of the spinneret hole. Increasing the L/D value of the spinnerets can not always improve the surface quality and the performances of PEEK fibers. The extrusion pressure is about 50% of that of the spinneret with 12 holes and 0.3 mm in diameter.

  12. Hydrophilization of Poly(ether ether ketone) Films by Surface-initiated Atom Transfer Radical Polymerization

    DEFF Research Database (Denmark)

    Fristrup, Charlotte Juel; Eskimergen, Rüya; Burkrinsky, J.T.;

    2008-01-01

    Poly(ether ether ketone) (PEEK) replaces aluminum and other metals in aerospace, electronics, medical, and automotive applications. Therefore, the demand for metallization of PEEK is continuously increasing. Metals seldom bond to a polymer without undergoing some chemical interaction - this is the......-modified PEEK using Surface-Initiated Atom Transfer Radical Polymerization (SI ATRP). Surface reduction of PEEK to form hydroxyl groups [1, 2, 3] was .performed prior to the attachment of 2-bromoisobutyrate initiating groups. Each modification step of PEEK as well as the polymer grafting was followed and...... mechanism leading to good adhesion. From the different types of bonding, the covalent bond at the polymer - metal interface is the strongest. In this work the surface ofPEEK is functionalized by covalently bounding of hydrophilic polymer brushes ofpoly(ethyleneglycol) methacrylate (PEGMA) from initiator...

  13. Modification of Poly(ether ether ketone Polymer for Fuel Cell Application

    Directory of Open Access Journals (Sweden)

    Devesh Shukla

    2013-01-01

    Full Text Available Polyelectrolyte membrane (PEM is an important part of PEM fuel cell. Nafion is a commercially known membrane which gives the satisfactory result in PEM fuel cell operating at low temperature. Present research paper includes functionalization of Poly(ether ether ketone (PEEK polymer with phosphonic acid group. The functionalization was done with the help of nickel-based catalyst. Further, the polymer was characterized by the FTIR, EDAX, DSC, TGA, and 1H NMR, and it was found that PEEK polymer was functionalized with phosphonic acid group with good thermal stability in comparison to virgin PEEK. Finally, the thin films of functionalized polymer were prepared by solution casting method, and proton conductivity of film samples was measured by impedance spectra whose value was found satisfactory with good thermal stability in comparison to commercially available Nafion membrane.

  14. Gamma-radiation effect on thermal ageing of butyl rubber compounds

    International Nuclear Information System (INIS)

    Butyl rubber has a comprehensive use in sealing systems, especially in tires inner tubes, due to their low permeability to gases. So, it is required that butyl rubber compounds show a better performance, more and more. Butyl rubber is provided with excellent mechanical properties and oxidation resistance. Besides showing these properties, radiation exposures impart modifications in physical-chemical and morphological properties on butyl rubber materials. When exposed to gamma-radiation, rubbers suffer changes in their mechanical and physical properties, caused by material degradation. The major radiation effect in butyl rubbers is chain scission; besides, ageing promotes too the same effect with further build-up of free radicals. This work aims to the study of gamma-radiation in physical-chemical properties of butyl rubber subjected to thermal ageing. Doses used herein were: 25 kGy, 50 kGy, 100 kGy, 150 kGy and 200 KGy. Samples were evaluated before and after ageing according to traditional essays, such as: hardness, tensile strength and elongation at break. From accomplished assessments it is possible to affirm that at doses higher than 50 kGy it was observed a sharp decreasing in butyl rubber physical-chemical properties, before and after exposure to ageing. (author)

  15. Gamma-radiation effect on thermal ageing of butyl rubber compounds

    Energy Technology Data Exchange (ETDEWEB)

    Scagliusi, Sandra R.; Cardoso, Elizabeth C.L.; Lugao, Ademar B., E-mail: srscagliusi@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Butyl rubber has a comprehensive use in sealing systems, especially in tires inner tubes, due to their low permeability to gases. So, it is required that butyl rubber compounds show a better performance, more and more. Butyl rubber is provided with excellent mechanical properties and oxidation resistance. Besides showing these properties, radiation exposures impart modifications in physical-chemical and morphological properties on butyl rubber materials. When exposed to gamma-radiation, rubbers suffer changes in their mechanical and physical properties, caused by material degradation. The major radiation effect in butyl rubbers is chain scission; besides, ageing promotes too the same effect with further build-up of free radicals. This work aims to the study of gamma-radiation in physical-chemical properties of butyl rubber subjected to thermal ageing. Doses used herein were: 25 kGy, 50 kGy, 100 kGy, 150 kGy and 200 KGy. Samples were evaluated before and after ageing according to traditional essays, such as: hardness, tensile strength and elongation at break. From accomplished assessments it is possible to affirm that at doses higher than 50 kGy it was observed a sharp decreasing in butyl rubber physical-chemical properties, before and after exposure to ageing. (author)

  16. 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)

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

    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 × 10−7 cm2/s) compared to a Nafion 212 membrane (5.37 × 10−7 cm2/s)

  19. Antiproliferative constituents from umbelliferae plants. V. A new furanocoumarin and falcarindiol furanocoumarin ethers from the root of Angelica japonica.

    Science.gov (United States)

    Fujioka, T; Furumi, K; Fujii, H; Okabe, H; Mihashi, K; Nakano, Y; Matsunaga, H; Katano, M; Mori, M

    1999-01-01

    The CHCl3 extract of the root of Angelica japonica showed high inhibitory activity against human gastric adenocarcinoma (MK-1) cell growth. From this extract, a new furanocoumarin named japoangelone and four furanocoumarin ethers of falcarindiol, named japoangelols A-D, were isolated together with caffeic acid methyl ester, four polyacetylenic compounds (panaxynol, falcarindiol, 8-O-acetylfalcarindiol, and (9Z)-1,9-heptadecadiene-4,6-diyne-3,8,11-triol), eight coumarins (osthol, isoimperatorin, scopoletin, byakangelicin, xanthotoxin, bergapten, oxypeucedanin methanolate, and oxypeucedanin hydrate), and two chromones (3'-O-acetylhamaudol, and hamaudol). The structures of the new isolates were determined based on spectral evidence. The ED50 of isolates against MK-1, HeLa, and B16F10 cell lines are reported. PMID:9987830

  20. Microwave Spectrum of the Ethylmethyl Ether Molecule

    Directory of Open Access Journals (Sweden)

    Kojiro Takagi

    2003-01-01

    Full Text Available We have observed rotational transitions of ethylmethyl ether (CH3CH2OCH3 in the 24-110 GHz frequency range. We newly assigned the transitions of four Q-branch series for J=1-38 with Ka=0-5 and six R-branch series of b-type transitions for J=7-37 with Ka=0-3. All these assigned transitions were observed to be split into two or four components due to the internal rotations of the methyl groups. We analyzed the averaged frequencies of the split components on the basis of the Watson A-reduced Hamiltonian, neglecting the effect of the internal rotations. A total of 122 transitions were fitted to eight molecular parameters to a 1s standard deviation of 24 kHz. The parameters A, B, C and DJ were improved, and DJK, Dk, dJ and dK were determined for the first time.

  1. The Lubrication Qualities of Dimethyl Ether (DME)

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius; Sorenson, Spencer C; Jakobsen, J.

    2002-01-01

    Dimethyl Ether (DME) has been recognised as a clean alternative for diesel oil for some years now. Fuelling diesel engines with DME solves their two most significant problems: The emission of particulate matter is virtually eliminated and the level of NOx can be reduced considerably by exhaust gas...... the viscosity, which plays a major role in the hydrodynamic lubrication regime. The lubricity of DME has been established by the medium frequency pressurised reciprocating rig (MFPRR) to be very low compared to the one of diesel oil. But the DME film limits the wear extent significantly compared to...... the case of dry sliding. By mixing DME with additives, the lubricity level is easily raised even above the one of diesel oil. The viscosity of DME has been established by the volatile fuel viscometer (VFVM) to be as low as 0.185 cSt @ 25 oC. It is also shown that this viscosity cannot be raised...

  2. Acyclic archaebacterial ether lipids in swamp sediments

    Science.gov (United States)

    Pauly, George G.; Van Vleet, Edward S.

    1986-06-01

    Acyclic phytanyl diether glycerol and biphytanyl ether lipids have been quantified in two modern swamp sediment cores in concentrations ranging up to 360 μg/ml porewater. Methanogenic bacteria are the only known source organisms which can inhabit the swamp sediments. Variations in relative abundance between these lipids may reflect taxonomic changes in methanogen populations or the stage of growth. Maxima in methanogen lipid concentrations coincide with local maxima of 13C of organic matter, possibly the result of a pool effect on CO 2 or acetate. Methane production estimates calculated from lipid concentrations in swamp sediments range from 0.1 to 1.3 mmol cm -2 yr -1, values which are consistent with published methane fluxes.

  3. Development of specialty chemicals from dimethyl ether

    Energy Technology Data Exchange (ETDEWEB)

    Tartamella, T.L.; Lee, S. [Univ. of Akron, OH (United States). Dept. of Chemical Engineering

    1996-12-31

    Dimethyl ether (DME) may be efficiently produced from coal-bases syngas in a high pressure, mechanically agitated slurry reactor. DME synthesis occurs in the liquid phase using a dual catalyst. By operating in a dual catalyst mode, DME may be converted from in-situ produced methanol resulting in higher methyl productivities and syngas conversions over methanol conversion alone. The feasibility of utilizing DME as a building block for more valuable specialty chemicals has been examined. A wide variety of petrochemicals may be produced from DME including light olefins, gasoline range hydrocarbons, oxygenates, and glycol precursors. These chemicals represent an important part of petroleum industries inventory of fine chemicals. Carbonylation, hydrocarbonylation, and oxidative dimerization are but a few of the reactions in which DME may undergo conversion. DME provides an additional route for the production of industrially important petrochemicals.

  4. Genotoxicity of di-butyl-phthalate and di-iso-butyl-phthalate in human lymphocytes and mucosal cells.

    Science.gov (United States)

    Kleinsasser, N H; Wallner, B C; Kastenbauer, E R; Weissacher, H; Harréus, U A

    2001-01-01

    The genotoxicity of phthalates, widely used plasticizers, has been shown previously for di-butyl-phthalate (DBP) and di-iso-butyl-phthalate (DBP) in human mucosal cells of the upper aerodigestive tract in a previous study using the Comet assay. Furthermore, higher genotoxic sensitivities of patients with squamous cell carcinomas of either the larynx or the oropharynx compared to non-tumor patients were described. Other authors have demonstrated DNA damage by a different phthalate in human lymphocytes. It was the aim of the present study to determine whether there is a correlation between the genotoxic sensitivities to DBP and its isomer DiBP in either mucosal cells or lymphocytes. The single-cell microgel electrophoresis assay (Comet assay) was applied to detect DNA strand breaks in human epithelial cells of the upper aerodigestive tract (n=132 specimens). Human mucosa was harvested from the oropharynx in non-tumor patients and patients with squamous cell carcinomas of the oropharynx. Laryngeal mucosa of patients with laryngeal squamous cell carcinomas was harvested as well. Peripheral lymphocytes (n=49 specimens) were separated from peripheral blood. Xenobiotics investigated were DBP, DiBP, and N'methyl-N'-nitro-N-nitrosoguanidine (MNNG) as positive control, respectively. For statistical analysis, the SPSS correlation analysis according to Pearson and the Wilcoxon test were performed. Genotoxicity was found for DBP and DiBP in epithelial cells and lymphocytes (Pintermediate correlation (r=0.570). Correlation in lymphocytes was the same (r=0.570). Phthalates have been investigated as a potential health hazard for a variety of reasons, including possible xenoestrogenic impact, peroxisome proliferation, and membrane destabilization. The present investigation suggests a correlated DNA-damaging impact of DBP and DiBP in human mucosal cells and in lymphocytes, respectively. PMID:11301413

  5. Formulating liquid ethers for microtubular SOFCs

    Science.gov (United States)

    Kendall, Kevin; Slinn, Matthew; Preece, John

    One of the key problems of applying solid oxide fuel cells (SOFCs) in transportation is that conventional fuels like kerosene and diesel do not operate directly in SOFCs without prereforming to hydrogen and carbon monoxide which can be handled by the nickel cermet anode. SOFCs can internally reform certain hydrocarbon molecules such as methanol and methane. However, other liquid fuels usable in petrol or diesel internal combustion engines (ICEs) have not easily been reformable directly on the anode. This paper describes a search for liquid fuels which can be mixed with petrol or diesel and also injected directly into an SOFC without destroying the nickel anode. When fuel molecules such as octane are injected onto the conventional nickel/yttria stabilised zirconia (Ni/YSZ) SOFC fuel electrode, the anode rapidly becomes blocked by carbon deposition and the cell power drops to near zero in minutes. This degeneration of the anode can be inhibited by injection of air or water into the anode or by some upstream reforming just before entry to the SOFC. Some smaller molecules such as methane, methanol and methanoic acid produce a slight tendency to carbon deposition but not sufficient to prevent long term operation. In this project we have investigated a large number of molecules and now found that some liquid ethers do not significantly damage the anode when directly injected. These molecules and formulations with other components have been evaluated in this study. The theory put forward in this paper is that carbon-carbon bonds in the fuel are the main reason for anode damage. By testing a number of fuels without such bonds, particularly liquid ethers such as methyl formate and dimethoxy methane, it has been shown that SOFCs can run without substantial carbon formation. The proposal is that conventional fuels can be doped with these molecules to allow hybrid operation of an ICE/SOFC device.

  6. Atmospheric oxidation of selected alcohols and esters

    Energy Technology Data Exchange (ETDEWEB)

    Becker, K.H.; Cavalli, F.

    2001-03-01

    The decision whether it is appropriate and beneficial for the environment to deploy specific oxygenated organic compounds as replacements for traditional solvent types requires a quantitative assessment of their potential atmospheric impacts including tropospheric ozone and other photooxidant formation. This involves developing chemical mechanisms for the gasphase atmospheric oxidation of the compounds which can be reliably used in models to predict their atmospheric reactivity under a variety of environmental conditions. Until this study, there was very little information available concerning the atmospheric fate of alcohols and esters. The objectives of this study were to measure the atmospheric reaction rates and to define atmospheric reaction mechanisms for the following selected oxygenated volatile organic compounds: the alcohols, 1-butanol and 1-pentanol, and the esters, methyl propionate and dimethyl succinate. The study has successfully addressed these objectives. (orig.)

  7. Photoenolization of o-Methylvalerophenone Ester Derivative.

    Science.gov (United States)

    Das, Anushree; Lao, Emily A; Gudmundsdottir, Anna D

    2016-05-01

    Photolysis of ester 1 in argon-saturated methanol and acetonitrile does not produce any product, whereas irradiation of 1 in oxygen-saturated methanol yields peroxide 2. Laser flash photolysis studies demonstrate that 1 undergoes intramolecular H atom abstraction to form biradical 3 (λmax ~340 nm), which intersystem crosses to form photoenols Z-4 and E-4 (λmax ~380 nm). Photoenols 4 decay by regenerating ester 1. With the aid of density functional theory calculations, it was concluded the photoenol E-4 does not undergo spontaneous lactonization or electrocyclic ring closure because the transition state barriers for these reactions are too large to compete with reketonization of E-4 to form 1. PMID:27061950

  8. Naturally occurring antifungal aromatic esters and amides

    International Nuclear Information System (INIS)

    During the search of antifungal natural products from terrestrial plants, a new long chained aromatic ester named grandiflorate along with spatazoate from Portulaca grandiflora and N-[2-methoxy-2-(4-methoxyphenyl) ethyl]-trans-cinnamide and aegeline from Solanum erianthum of Nigeria were isolated and tested against six fungal species. The known constituents have not been reported so far from mentioned investigated plants. Structures of the isolated compounds were elucidated with the aid of spectroscopic techniques including two dimensional NMR experiments. Among the compounds, the esters found more potent than amides against Candida albicans and Aspergillus flavus. The new compound grandiflorate gave response against all tested fungal species while aegeline was found to give lowest inhibition during this study. (author)

  9. Gas chromatographic retention data of wax esters

    Czech Academy of Sciences Publication Activity Database

    Stránský, Karel; Zarevúcka, Marie; Valterová, Irena; Wimmer, Zdeněk

    2006-01-01

    Roč. 1128, č. 1/2 (2006), s. 208-219. ISSN 0021-9673 R&D Projects: GA ČR(CZ) GA203/04/0120; GA AV ČR(CZ) IAA4055403 Institutional research plan: CEZ:AV0Z40550506 Keywords : Wax esters * gas chromatography * Kováts index * Reduced Kováts index Subject RIV: CC - Organic Chemistry Impact factor: 3.554, year: 2006

  10. Synthesis of ester-siloxane multiblock copolymers

    OpenAIRE

    Antić Vesna V.; Vučković Marija V.; Govedarica Milutin N.

    2004-01-01

    It was shown that the two-stage transesterification/polycondensation reaction in the melt, can successfully be applied for the preparation of poly(butylene terephtalate-dimethylsiloxane) multiblock copolymers. Three series of co-polymers were synthesized, using poly(dimethylsiloxanes) bearing ester (two series) and hydroxy -end groups as reactants. The structure and composition of the obtained copolymers were determined by 1H NMR spectroscopy A mechanism, i.e. an order of reaction steps, invo...

  11. Ethyl ester production from (RBD palm oil

    Directory of Open Access Journals (Sweden)

    Oscar Mauricio Martínez Ávila

    2010-07-01

    Full Text Available This work develops a methodology for obtaining ethyl esters from RBD (refined, bleached and deodorised palm oil by evaluating the oil’s transesterification and separation. Two catalysts were first tested (KOH and NaOH by studying the effect of water presence on the reaction. The separation process was then evaluated by using water and water-salt and water-acid mixtures, establishing the agent offering the best results and carrying out the purification stage. Raw materials and products were characterised for comparing the latter with those obtained by traditional means and verifying the quality of the esters so produced; minimum differences were found bet-ween both. The proposed methodology thus allows esters to be used as raw material in petrochemical industry applications. A more profitable process can be obtained compared to those used today, given the amounts of separation agent so established (1% H3PO4 solution, in water. The overall process achieved 74.4% yield, based on the oil being used.

  12. Synthesis and Adsorption Property of Dihydroxyl Azacrown Ether-Grafted Chitosan

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A novel dihydroxyl azacrown ether chitosan was synthesized by reacting dihydroxyl azacrown ether with epoxy activated chitosan. The adsorption property of the azacrown ether chitosan for Pb2+, Cr3+, and Ag+, were determined. The experimental results showed that the dihydroxyl azacrown ether grafted chitosan has high adsorption capacity and high selectivity for some metal ions.

  13. Environmental potential of the alternative automotive fuels biogas, ethanol, methanol, natural gas, rape oil methyl ester, and dimethyl ether

    International Nuclear Information System (INIS)

    The aim of the project was to estimate the future emission levels when using alternative fuels, as a contribution to the Committee for Evaluation of Alternative Automotive Fuels (organized by the Swedish Ministry of Environment). The method used for the project was to use the today's knowledge about the emission levels and the emission control technology as a base for the estimation of what additional potential there is to decrease the emissions by coming development of vehicles and the emission control technology. The results of the analysis and the estimations show that there exist a positive development for all types of vehicles and alternative fuels. However, there will be a difference between the different fuel alternatives depending on chemical and physical differences between the different fuels. There will also be a difference in the possibilities of the different fuels to capture a market which will have certain impact on the willingness and the economic possibilities for the car manufacturers to invest in the development needed to reach low emission levels. 124 refs

  14. Deformation Behaviour During Cold Drawing of Nanocomposites Based on Single Wall Carbon Nanotubes and Poly(ether ester) Copolymers

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez,J.; Garcia-Gutierrez, M.; Nogales, A.; Rueda, D.; Sanz, A.; Sics, I.; Hsiao, B.; Roslaniec, Z.; Broza, G.; Ezquerra, T.

    2007-01-01

    Relationships between the macroscopic deformation behaviour and microstructure of a pure (PBT-b-PTMO) block copolymer and a polymer nanocomposite (PBT-b-PTMO + 0.2 wt% SWCNT) were investigated by simultaneous small- and wide-angle X-ray scattering (SAXS and WAXS) during tensile deformation using synchrotron radiation. The Young's modulus was found to be 15% higher for the nanocomposite than for the pure block copolymer as well as the yield strength, while the elongation-to-break was less than a half. This different behaviour can be explained by taking into account the different structural features revealed by SAXS and WAXS and thus considering that SWCNT act as anchors in the nanocomposite, sharing the applied stress with the PBT crystals and partially preventing the flexible, non-crystallisable PTMO chains to elongate.

  15. Elastohydrodynamic film thickness measurements with advanced ester, fluorocarbon, and polyphenyl ether lubricants to 589 K (600 F)

    Science.gov (United States)

    Parker, R. J.; Kannel, J. W.

    1971-01-01

    Elastohydrodynamic (EHD) film thicknesses have been measured, by means of an X-ray technique, under conditions that closely simulate the ball-race contact in advanced turbine engine thrust bearings. The experiments were conducted with a rolling-disk machine using disks which yield a contact zone similar to that in the actual bearing. Both the rolling and spinning motions of the ball relative to the race were simulated by the apparatus. Four lubricants were evaluated at temperatures to 600 F and maximum Hertz stresses to 350,000 psi. The X-ray film thickness data correlated well with observations of surface distress (or lack thereof) in full-scale bearing tests with the same lubricants under similar conditions of temperature and load. The predicted variation of film thickness with speed and viscosity as verified, although the magnitude of measured film thickness was generally one-half to one-third of predicted values. An effect of stress greater than predicted was consistently observed in the higher stress range.

  16. Measurements of activity coefficients at infinite dilution for organic solutes and water in the ionic liquid 1-butyl-1-methylpyrrolidinium tricyanomethanide

    International Nuclear Information System (INIS)

    Highlights: • Measurements of activity coefficients at infinite dilution using GLC. • 62 organic solvents and water in the ionic liquid 1-butyl-1-methylpyrrolidinium tricyanomethanide. • High capacity for thiophene, 1.37 at T = 328.15 K. • Possible entrainer for extraction of sulfur, or nitrogen compounds from fuels. • The excess thermodynamic functions and the gas–liquid partition coefficients were calculated. -- Abstract: The activity coefficients at infinite dilution, γ13∞, for 62 solutes, including alkanes, cycloalkanes, alkenes, alkynes, aromatic hydrocarbons, alcohols, water, thiophene, ethers, ketones, acetonitrile, pyridine and 1-nitropropane in the ionic liquid 1-butyl-1-methylpyrrolidinium tricyanomethanide, [BMPYR][TCM] were determined by gas–liquid chromatography at six temperatures over the range of (318.15 to 368.15) K. The partial molar excess Gibbs free energy, ΔG1E∞, enthalpy ΔH1E∞, and entropy term TrefΔS1E,∞ at infinite dilution were calculated from the experimental γ13∞ values obtained over the temperature range. The densities of [BMPYR][TCM] were measured within temperature range from 318.15 K to 368.15 K. The gas–liquid partition coefficients, KL were calculated for all solutes. The values of selectivity for few separation problems as hexane/benzene, cyclohexane/benzene, heptane/thiophene were calculated from γ13∞ and compared to literature values for N-methyl-2-pyrrolidinone (NMP), sulfolane, and other ionic liquids based on [BMPYR]+ cation. In comparison with the former measured ILs, [BMPYR][TCM] present quite high selectivity for the separation of aromatic hydrocarbons and aliphatics hydrocarbons, an average capacity for benzene. The data presented here shows that [BMPYR][TCM] ionic liquid can be used as an alternative solvent for the separation of thiophene from the aliphatic hydrocarbons

  17. Pengaruh Katalis H2SO4 pada Reaksi Epoksidasi Metil Ester PFAD (Palm Fatty Acid Distillate)

    OpenAIRE

    Sinaga, Mersi Suriani

    2010-01-01

    Ester epoksi selain sebagai pelunak juga dapat memperbaiki ketahanan komponen polivinil klorida (PVC) terhadap panas dan cahaya. Penelitian ini dilakukan untuk merumuskan kondisi katalis yang sesuai bagi pembuatan senyawa epoksi metil ester PFAD dari senyawa metil ester PFAD. Metil ester PFAD terdiri dari ester lemak jenuh dan tidak jenuh., metode pemisahan kristalisasi dengan pelarut metanol untuk memisahkan ester lemak jenuh dari ester lemak tak jenuh, yang bertujuan meningkatkan kemamp...

  18. Structure-activity relationship studies of new rifamycins containing l-amino acid esters as inhibitors of bacterial RNA polymerases.

    Science.gov (United States)

    Czerwonka, Dominika; Domagalska, Joanna; Pyta, Krystian; Kubicka, Marcelina M; Pecyna, Paulina; Gajecka, Marzena; Przybylski, Piotr

    2016-06-30

    New rifamycins (1-12) combined with different l-amino acids, containing methyl, ethyl, tert-butyl and benzyl groups at the ester part, via amine linkage, were synthesized and their structures in solution were determined by spectroscopic FT-IR and 1D and 2D NMR methods as well as visualized by DFT calculations. Two types of rifamycin structures were detected in solution: a zwitterionic one with the transferred proton from O(8)H phenol to secondary N(38) atom and a pseudocyclic structure stabilized via formation of intramolecular H-bond within the protonated basic C(3)-substituent. The presence of these rifamycins' structures influenced physico-chemical (logP, solubility) parameters and antibacterial properties. The bulkiness at the ester substituent of new rifamycins containing aromatic l-amino acids was found to be an important factor, besides the solubility, to achieve relatively high antibacterial activity against reference S. epidermidis and reference S. aureus and MRSA strains (MICs 0.016-0.063 μg/mL), comparable to that of rifampicin. SAR for the novel derivatives was discussed in view of the calculated structures of rifamycin-RNAP complexes. PMID:27061985

  19. 77 FR 1682 - Butylate, Fenoxycarb, Sodium Tetrathiocarbonate, and Temephos Registration Review Final Decisions...

    Science.gov (United States)

    2012-01-11

    ... field corn, pop corn, and sweet corn. The last butylate pesticide product registered for use in the... a soil fumigant used for the management of nematodes and phytophthora root rot, oak root fungus,...

  20. A comparison of the effect of intranasal desmopressin and intramuscular hyoscine N-butyl bromide combination with intramuscular hyoscine N-butyl bromide alone in acute renal colic

    Directory of Open Access Journals (Sweden)

    Abdol-Reza Kheirollahi

    2010-01-01

    Full Text Available Background: Patients with acute renal colic usually require immediate diagnosis and treatment. In this clinical trial analgesic effect of hyoscine N-butyl bromide and desmopressin combination in comparison with hyoscine N-butyl bromide alone in patients with acute renal colic induced by urinary stones was assessed. Methods: The study included 114 patients randomly allocated in two groups (A and B. Patients in group A received 20 mg intramuscular hyoscine N-butyl bromide at admission time and patients in group B received 20 μg of intranasal desmopressin in combination with 20 mg intramuscular hyoscine N-butyl bromide. A visual analogue scale (VAS; a 10-cm horizontal scale ranging from "zero or no pain" to "10 or unbearable pain" was hired to assess the patients′ pain severity at baseline, 30 and 60 minutes after the treatments. Results: On admission, the pain level was similar in both groups (group A: 8.95 ± 0.11 and group B: 8.95 ± 0.12. In group A, the mean of pain level showed a decrease after 30 minutes (group A: 7.26 ± 0.25 and group B: 5.95 ± 0.28 but further decreasing did not occur; however in group B, the pain consistently decreased and the mean after 60 minutes was significantly decreased (group A: 6.80 ± 0.31 and group B: 3.71 ± 0.31. No side effects were detected in this study. Conclusions: The combination of hyoscine N-butyl bromide and desmopressin is more effective than hyoscine N-butyl bromide alone in patients with renal colic. Further studies are recommended to validate these findings and compare the different doses of desmopressin.