Sample records for ethyl vinyl ether

  1. Elastic electron scattering by ethyl vinyl ether

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Khakoo, M. A.; Hong, L.; Kim, B.

    2010-02-15

    We report measured and calculated results for elastic scattering of low-energy electrons by ethyl vinyl ether (ethoxyethene), a prototype system for studying indirect dissociative attachment processes that may play a role in DNA damage. The integral cross section displays the expected {pi}{sup *} shape resonance. The agreement between the calculated and measured cross sections is generally good.

  2. Reactions of NO 3 with the man-made emissions 2-methylpent-2-ene, ( Z)-3-methylpent-2-ene, ethyl vinyl ether, and the stress-induced plant emission ethyl vinyl ketone

    NASA Astrophysics Data System (ADS)

    Pfrang, Christian; Tooze, Christopher; Nalty, Andrew; Canosa-Mas, Carlos E.; Wayne, Richard P.

    Rate coefficients for reactions of nitrate radicals (NO 3) with the anthropogenic emissions 2-methylpent-2-ene, ( Z)-3-methylpent-2-ene, ethyl vinyl ether, and the stress-induced plant emission ethyl vinyl ketone (pent-1-en-3-one) were determined to be (9.3±1.1)×10 -12, (9.3±3.2)×10 -12, (1.7±1.3)×10 -12 and (9.4±2.7)×10 -17 cm 3 molecule -1 s -1. We performed kinetic experiments at room temperature and atmospheric pressure using a relative-rate technique with GC-FID analysis. Experiments with ethyl vinyl ether required a modification of our established procedure that might introduce additional uncertainties, and the errors suggested reflect these difficulties. Rate coefficients are discussed in terms of electronic and steric influences. Atmospheric lifetimes with respect to important oxidants in the troposphere were calculated. NO 3-initiated oxidation is found to be the strongly dominating degradation route for 2-methylpent-2-ene, ( Z)-3-methylpent-2-ene and ethyl vinyl ether. Atmospheric concentrations of the alkenes and their relative contribution to the total NMHC emissions from trucks can be expected to increase if plans for the introduction of particle filters for diesel engines are implemented on a global scale. Thus more kinetic data are required to better evaluate the impact of these emissions.

  3. Atmospheric degradation of 2-chloroethyl vinyl ether, allyl ether and allyl ethyl ether: Kinetics with OH radicals and UV photochemistry.

    PubMed

    Antiñolo, M; Ocaña, A J; Aranguren, J P; Lane, S I; Albaladejo, J; Jiménez, E

    2017-08-01

    Unsaturated ethers are oxygenated volatile organic compounds (OVOCs) emitted by anthropogenic sources. Potential removal processes in the troposphere are initiated by hydroxyl (OH) radicals and photochemistry. In this work, we report for the first time the rate coefficients of the gas-phase reaction with OH radicals (k OH ) of 2-chloroethyl vinyl ether (2ClEVE), allyl ether (AE), and allyl ethyl ether (AEE) as a function of temperature in the 263-358 K range, measured by the pulsed laser photolysis-laser induced fluorescence technique. No pressure dependence of k OH was observed in the 50-500 Torr range in He as bath gas, while a slightly negative T-dependence was observed. The temperature dependent expressions for the rate coefficients determined in this work are: The estimated atmospheric lifetimes (τ OH ) assuming k OH at 288 K were 3, 2, and 4 h for 2ClEVE, AE and AEE, respectively. The kinetic results are discussed in terms of the chemical structure of the unsaturated ethers by comparison with similar compounds. We also report ultraviolet (UV) and infrared (IR) absorption cross sections (σ λ and σ(ν˜), respectively). We estimate the photolysis rate coefficients in the solar UV actinic region to be less than 10 -7 s -1 , implying that these compounds are not removed from the atmosphere by this process. In addition, from σ(ν˜) and τ OH , the global warming potential of each unsaturated ether was calculated to be almost zero. A discussion on the atmospheric implications of the titled compounds is presented. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Molecular Engineering of Liquid Crystalline Polymers by Living Polymerization. 8. Influence of Molecular Weight on the Phase Behavior pf Poly(Omega-((4-cyano-4’Biphenyl)oxy)alkyl Vinyl Ether)s with Ethyl, Propyl and Butyl Alkyl Groups

    DTIC Science & Technology

    1990-10-16

    methanol (15 ml). The mixture was refluxed for 12 hr. After cooling and filtration (to remove the catalyst ) the solvent was distilled in a rotavapor and...was controlled by the monomer/initiator ([M]/[I]0 ) ratio. After quenching the polymerization with ammoniacal methanol , the reaction mixture was...The Phase Behavior of Poly(co-[(4-cyano-4’- biphenyl)oxy] alkyl Vinyl Ether]s with Ethyl, Propyl and Butyl Alkyl Groups Acc,--.o ,; ., x .... V

  5. Ethyl ether

    Integrated Risk Information System (IRIS)

    Ethyl ether ; CASRN 60 - 29 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effect

  6. Stereocontrolled Cyanohydrin Ether Synthesis through Chiral Brønsted Acid-Mediated Vinyl Ether Hydrocyanation

    PubMed Central

    Lu, Chunliang; Su, Xiaoge; Floreancig, Paul E.

    2013-01-01

    Vinyl ethers can be protonated to generate oxocarbenium ions that react with Me3SiCN to form cyanohydrin alkyl ethers. Reactions that form racemic products proceed efficiently upon converting the vinyl ether to an α-chloro ether prior to cyanide addition in a pathway that proceeds through Brønsted acid-mediated chloride ionization. Enantiomerically enriched products can be accessed by directly protonating the vinyl ether with a chiral Brønsted acid to form a chiral ion pair. Me3SiCN acts as the nucleophile and PhOH serves as a stoichiometric proton source in a rare example of an asymmetric bimolecular nucleophilic addition reaction into an oxocarbenium ion. Computational studies provide a model for the interaction between the catalyst and the oxocarbenium ion. PMID:23968162

  7. Maleate/vinyl ether UV-cured coatings: Effects of composition on curing and properties

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Noren, G.K.

    1996-10-01

    The effect of the composition of the maleate polyester and the vinyl ether terminated compound on their UV-curing and properties has been investigated. Linear unsaturated polyester resins based on maleic anhydride and 1,5-pentane diol were synthesized. The molecular weight of the unsaturated polyesters was varied by changing the ratio of maleic anhydride to 1,5-pentane diol and the double bond equivalent weight was varied by replacing maleic anhydride with succinic anhydride. Coating formulations containing these unsaturated polyesters, triethylene glycol divinyl ether and a free radical photoinitiator were crosslinked in the presence of UV light. The coatings were very brittle, exhibiting tensilemore » strengths in the range of 1.5-4.0 MPa and elongations of only 3-7%. Diethyl maleate and isobutyl vinyl ether were effective diluents for reducing viscosity but reduced the cure speed. A vinyl ether urethane oligomer was synthesized and enhanced the flexibility and toughness of the coatings when substituted for triethylene glycol divinyl ether.« less

  8. Thermodynamic properties (enthalpy, bond energy, entropy, and heat capacity) and internal rotor potentials of vinyl alcohol, methyl vinyl ether, and their corresponding radicals.

    PubMed

    da Silva, Gabriel; Kim, Chol-Han; Bozzelli, Joseph W

    2006-06-29

    Vinyl alcohols (enols) have been discovered as important intermediates and products in the oxidation and combustion of hydrocarbons, while methyl vinyl ethers are also thought to occur as important combustion intermediates. Vinyl alcohol has been detected in interstellar media, while poly(vinyl alcohol) and poly(methyl vinyl ether) are common polymers. The thermochemical property data on these vinyl alcohols and methyl vinyl ethers is important for understanding their stability, reaction paths, and kinetics in atmospheric and thermal hydrocarbon-oxygen systems. Enthalpies , entropies , and heat capacities (C(p)()(T)) are determined for CH(2)=CHOH, C(*)H=CHOH, CH(2)=C(*)OH, CH(2)=CHOCH(3), C(*)H=CHOCH(3), CH(2)=C(*)OCH(3), and CH(2)=CHOC(*)H(2). Molecular structures, vibrational frequencies, , and C(p)(T) are calculated at the B3LYP/6-31G(d,p) density functional calculation level. Enthalpies are also determined using the composite CBS-Q, CBS-APNO, and G3 methods using isodesmic work reactions to minimize calculation errors. Potential barriers for internal rotors are calculated at the B3LYP/6-31G(d,p) level and used to determine the hindered internal rotational contributions to entropy and heat capacity. The recommended ideal gas phase values calculated in this study are the following (in kcal mol(-1)): -30.0, -28.9 (syn, anti) for CH(2)=CHOH; -25.6, -23.9 for CH(2)=CHOCH(3); 31.3, 33.5 for C(*)H=CHOH; 27.1 for anti-CH(2)=C(*)OH; 35.6, 39.3 for C(*)H=CHOCH(3); 33.5, 32.2 for CH(2)=C(*)OCH(3); 21.3, 22.0 for CH(2)=CHOC(*)H(2). Bond dissociation energies (BDEs) and group additivity contributions are also determined. The BDEs reveal that the O-H, O-CH(3), C-OH, and C-OCH(3) bonds in vinyl alcohol and methyl vinyl ether are similar in energy to those in the aromatic molecules phenol and methyl phenyl ether, being on average around 3 kcal mol(-1) weaker in the vinyl systems. The keto-enol tautomerization enthalpy for the interconversion of vinyl alcohol to acetaldehyde is

  9. Furfuryl ethyl ether: important aging flavor and a new marker for the storage conditions of beer.

    PubMed

    Vanderhaegen, Bart; Neven, Hedwig; Daenen, Luk; Verstrepen, Kevin J; Verachtert, Hubert; Derdelinckx, Guy

    2004-03-24

    Recently, it was reported that furfuryl ethyl ether is an important flavor compound indicative of beer storage and aging conditions. A study of the reaction mechanism indicates that furfuryl ethyl ether is most likely formed by protonation of furfuryl alcohol or furfuryl acetate followed by S(N)2-substitution of the leaving group by the nucleophilic ethanol. For the reaction in beer, a pseudo-first-order reaction kinetics was derived. A close correlation was found between the values predicted by the kinetic model and the actual furfuryl ethyl ether concentration evolution during storage of beer. Furthermore, 10 commercial beers of different types, aged during 4 years in natural conditions, were analyzed, and it was found that the furfuryl ethyl ether flavor threshold was largely exceeded in each type of beer. In these natural aging conditions, lower pH, darker color, and higher alcohol content were factors that enhanced furfuryl ethyl ether formation. On the other hand, sulfite clearly reduced furfuryl ethyl ether formation. All results show that the furfuryl ethyl ether concentration is an excellent time-temperature integrator for beer storage.

  10. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Etbe) ...

    EPA Pesticide Factsheets

    The IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) was released for external peer review in June 2017. EPA’s Science Advisory Board’s (SAB) Chemical Assessment Advisory Committee (CAAC) will conduct a peer review of the scientific basis supporting the ETBE assessment and release a final report of their review. Information regarding the peer review can be found on the SAB website. EPA is conducting an Integrated Risk Information System (IRIS) health assessment for Ethyl Tertiary Butyl Ether (ETBE). The outcome of this project is a Toxicological Review and IRIS Summary for ETBE that will be entered into the IRIS database.

  11. Comparison of clinical results for the use of ethyl acetate and diethyl ether in the formalin-ether sedimentation technique performed on polyvinyl alcohol-preserved specimens.

    PubMed Central

    Garcia, L S; Shimizu, R

    1981-01-01

    One hundred fecal specimens preserved in polyvinyl alcohol fixative were examined by the Formalin-ether sedimentation technique with ethyl acetate substituted for diethyl ether. Technical performance of the procedures, appearance and amount of sediment obtained, and organism morphology were comparable. Also, ethyl acetate is less flammable and, therefore, less dangerous to use than diethyl ether. Results of parasite recovery when diethyl ether or ethyl acetate was used revealed few clinical relevant differences, most of which could also have been attributed to other variables inherent in this type of diagnostic testing. PMID:7229014

  12. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Etbe) ...

    EPA Pesticide Factsheets

    In September 2016, EPA released the draft IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) for public comment and discussion. The draft assessment was reviewed internally by EPA and by other federal agencies and White House Offices before public release. Consistent with the May 2009 IRIS assessment development process, all written comments on IRIS assessments submitted by other federal agencies and White House Offices are made publicly available. Accordingly, interagency comments and the interagency science consultation materials provided to other agencies, including interagency review drafts of the IRIS Toxicological Review of Ethyl Tertiary Butyl Ether are posted on this site. EPA is undertaking an new health assessment for ethyl tertiary butyl ether (ETBE) for the Integrated Risk Information System (IRIS). The outcome of this project will be a Toxicological Review and IRIS Summary of ETBE that will be entered on the IRIS database. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment process, i.e., hazard identification and dose-response evaluation. IRIS assessments are used nationally and internationally in combination with specific situational exposure assessment infor

  13. 46 CFR 151.50-42 - Ethyl ether.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-42 Ethyl ether. (a)(1) Gravity tanks... openings shall be in the top of the tank. (2) Pressure vessel type tanks shall be designed for the maximum pressure to which they may be subjected when pressure is used to discharge the cargo, but in no case shall...

  14. Biocatalytic Asymmetric Synthesis of (1R, 2S)-N-Boc-vinyl-ACCA Ethyl Ester with a Newly Isolated Sphingomonas aquatilis.

    PubMed

    Zhu, Shaozhou; Shi, Ying; Zhang, Xinyu; Zheng, Guojun

    2018-02-01

    1-amino cyclopropane-1-carboxylic acid (ACCA) and its derivatives are essential pharmacophoric unit that widely used in drug research and development. Specifically, (1R, 2S)-N-Boc-vinyl-ACCA ethyl ester (vinyl-ACCA) is a key chiral intermediate in the synthesis of highly potent hepatitis C virus (HCV) NS3/4A protease inhibitors such as asunaprevir and simeprevir. Developing strategies for the asymmetric synthesis of vinyl-ACCA is thus extremely high demand. In this study, 378 bacterial strains were isolated from soil samples using N-Boc-vinyl-ACCA ethyl ester as the sole carbon source and were screened for esterase activity. Fourteen of which worked effectively for the asymmetric synthesis of (1R, 2S)-N-Boc-1-vinyl ACCA ethyl ester. The strain CY-2, identified as Sphingomonas aquatilis, which showed the highest stability and enantioselectivity was selected as whole cell biocatalyst for further study. A systematic study of all factors influencing the enzymatic hydrolysis was performed. Under optimized conditions, resolution of rac-vinyl-ACCA to (1R, 2S)-N-Boc-1-vinyl ACCA ethyl ester with 88.2% ee and 62.4% conversion (E = 9) was achieved. Besides, S. aquatilis was also used to transform other 10 different substrates. Notably, it was found that 7 of them could be stereoselectively hydrolyzed, especially for (1R,2S)-1-amino-vinyl-ACCA ethyl ester hydrochloride (99.6% ee, E>200). Our investigations provide a new efficient whole cell biocatalyst for resolution of ACCA and might be developed for industry application.

  15. Convenient Route to Di- and Triorganosilyl Ethyl Ethers and the Corresponding Di- and Triorganosilanes

    DTIC Science & Technology

    1993-11-22

    example R2 R’SiH. Early reports indicated that formation of R3SiCI or R2SiCI 2 compounds by the addition of organolithium or Grignard reagents to...corresponding Grignard reagents are far less effective for the substiution reactions. 7 3 Table I. Conversion of (CH3 CH20) 4Si to Organosilyl Ethyl Ethers (X...ABSTRACT (Maximum 200 words) Tetraethoxysilane was treated with alkyl- and aryllithium reagents for the preparation of organosilyl ethyl ethers of the

  16. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Etbe) ...

    EPA Pesticide Factsheets

    In August 2013, EPA released the draft literature searches and associated search strategies, evidence tables, and exposure response arrays for ETBE to obtain input from stakeholders and the public prior to developing the draft IRIS assessment. Specifically, EPA was interested in comments on the following: Draft literature search strategies The approach for identifying studies The screening process for selecting pertinent studies The resulting list of pertinent studies Preliminary evidence tables The process for selecting studies to include in evidence tables The quality of the studies in the evidence tables The literature search strategy, which describes the processes for identifying scientific literature, contains the studies that EPA considered and selected to include in the evidence tables. The preliminary evidence tables and exposure-response arrays present the key study data in a standardized format. The evidence tables summarize the available critical scientific literature. The exposure-response figures provide a graphical representation of the responses at different levels of exposure for each study in the evidence table. The draft Toxicological Review of Ethyl Tertiary Butyl Ether provides scientific support and rationale for the hazard and dose-response assessment pertaining to chronic exposure to ethyl tertiary butyl ether.

  17. Interfacial Properties of Thin Films of Poly(vinyl ether)s with Architectural Design in Water

    NASA Astrophysics Data System (ADS)

    Oda, Yukari; Itagaki, Nozomi; Sugimoto, Sin; Kawaguchi, Daisuke; Matsuno, Hisao; Tanaka, Keiji

    Precise design of primary structure and architecture of polymers leads to the well-defined structure, unique physical properties, and excellent functions not only in the bulk but also at the interfaces. We here constructed functional polymer interfaces in water based on the architectural design of poly(vinyl ether)s with oxyethylene side-chains (POEVE). A branched polymer with POEVE parts was preferentially segregated at the air interface in the matrix of poly(methyl methacrylate). As an alternative way to prepare the POEVE surface, the cross-linked hydrogel thin films were prepared. The moduli of the hydrogel films near the water interfaces, which were examined by force-distance curve measurements using atomic force microscopy, were greatly sensitive to the cross-linking density of the polymers. Diffuse interfaces of POEVE chains at the water interface make it possible to prevent the platelet adhesion on the films.

  18. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Public Comment Draft)

    EPA Science Inventory

    In September 2016, the U.S. Environmental Protection Agency's (USEPA) released the draft Integrated Risk Information System (IRIS) Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE). Consistent with the 2013 IRIS Enhancements, draft IRIS assessments are released prior to e...

  19. IRIS Toxicological Review and Summary Documents for Tertiary Amyl Ethyl Ether (Taee)

    EPA Science Inventory

    This is EPA's first assessment of the noncancer health effects and carcinogenic potential of tertiary amyl ethyl ether (TAEE). The IRIS program is preparing an assessment that will incorporate health effects information available for TAEE, and current risk assessment methods. T...

  20. Vapor intrusion risk of fuel ether oxygenates methyl tert-butyl ether (MTBE), tert-amyl methyl ether (TAME) and ethyl tert-butyl ether (ETBE): A modeling study.

    PubMed

    Ma, Jie; Xiong, Desen; Li, Haiyan; Ding, Yi; Xia, Xiangcheng; Yang, Yongqi

    2017-06-15

    Vapor intrusion of synthetic fuel additives represents a critical yet still neglected problem at sites contaminated by petroleum fuel releases. This study used an advanced numerical model to investigate the vapor intrusion potential of fuel ether oxygenates methyl tert-butyl ether (MTBE), tert-amyl methyl ether (TAME), and ethyl tert-butyl ether (ETBE). Simulated indoor air concentration of these compounds can exceed USEPA indoor air screening level for MTBE (110μg/m 3 ). Our results also reveal that MTBE has much higher chance to cause vapor intrusion problems than TAME and ETBE. This study supports the statements made by USEPA in the Petroleum Vapor Intrusion (PVI) Guidance that the vertical screening criteria for petroleum hydrocarbons may not provide sufficient protectiveness for fuel additives, and ether oxygenates in particular. In addition to adverse impacts on human health, ether oxygenate vapor intrusion may also cause aesthetic problems (i.e., odour and flavour). Overall, this study points out that ether oxygenates can cause vapor intrusion problems. We recommend that USEPA consider including the field measurement data of synthetic fuel additives in the existing PVI database and possibly revising the PVI Guidance as necessary. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (External Review Draft)

    EPA Science Inventory

    The IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) was released for external peer review in June 2017. EPA’s Science Advisory Board’s (SAB) Chemical Assessment Advisory Committee (CAAC) will conduct a peer review of the scientific basis supporting the ETB...

  2. Acidolysis small molecular phenolic ether used as accelerator in photosensitive diazonaphthaquinone systems

    NASA Astrophysics Data System (ADS)

    Zhou, Haihua; Zou, Yingquan

    2006-03-01

    The photosensitive compounds in the photosensitive coatings of positive PS plates are the diazonaphthaquinone derivatives. Some acidolysis small molecular phenolic ethers, which were synthesized by some special polyhydroxyl phenols with vinyl ethyl ether, are added in the positive diazonaphthaquinone photosensitive composition to improve its sensitivity, composed with photo-acid-generators. The effects to the photosensitivity, anti-alkali property, anti-isopropyl alcohol property, dot resolution and line resolution of the coatings are studied with different additive percent of the special phenolic ethers. In the conventional photosensitive diazonaphthaquinone systems for positive PS plates, the photosensitivity is improved without negative effects to resolution, anti-alkali and anti-isopropyl alcohol properties when added about 5% of the special acidolysis phenolic ethers, EAAE or DPHE, composed with photo-acid-generators.

  3. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (External Review Draft, 2009)

    EPA Science Inventory

    EPA is conducting a peer review and public comment of the scientific basis supporting the human health hazard and dose-response assessment of ethyl tertiary butyl ether (ETBE) that when finalized will appear on the Integrated Risk Information System (IRIS) database.

  4. 40 CFR 721.7700 - Poly(oxy-1,2-ethanediyl), α-hydro-ω-(oxiranylmethoxy)-, ether with 2-ethyl-2-(hydroxymethyl)-1,3...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Poly(oxy-1,2-ethanediyl), α-hydro-Ï... Poly(oxy-1,2-ethanediyl), α-hydro-ω-(oxiranylmethoxy)-, ether with 2-ethyl-2-(hydroxymethyl)-1,3... substance identified as poly(oxy-1,2-ethanediyl),α-hydro-ω-(oxiranylmethoxy)-, ether with 2-ethyl-2...

  5. 40 CFR 721.7700 - Poly(oxy-1,2-ethanediyl), α-hydro-ω-(oxiranylmethoxy)-, ether with 2-ethyl-2-(hydroxymethyl)-1,3...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Poly(oxy-1,2-ethanediyl), α-hydro-Ï... Poly(oxy-1,2-ethanediyl), α-hydro-ω-(oxiranylmethoxy)-, ether with 2-ethyl-2-(hydroxymethyl)-1,3... substance identified as poly(oxy-1,2-ethanediyl),α-hydro-ω-(oxiranylmethoxy)-, ether with 2-ethyl-2...

  6. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Interagency Science Consultation Draft)

    EPA Science Inventory

    In September 2016, EPA released the draft IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) for public comment and discussion. The draft assessment was reviewed internally by EPA and by other federal agencies and White House Offices before public release. Consistent ...

  7. Separator Membrane from Crosslinked Poly(Vinyl Alcohol) and Poly(Methyl Vinyl Ether-alt-Maleic Anhydride)

    PubMed Central

    Rohatgi, Charu Vashisth; Dutta, Naba K.; Choudhury, Namita Roy

    2015-01-01

    In this work, we report separator membranes from crosslinking of two polymers, such as poly vinyl alcohol (PVA) with an ionic polymer poly(methyl vinyl ether-alt-maleic anhydride) (PMVE-MA). Such interpolymer-networked systems were extensively used for biomedical and desalination applications but they were not examined for their potential use as membranes or separators for batteries. Therefore, the chemical interactions between these two polymers and the influence of such crosslinking on physicochemical properties of the membrane are systematically investigated through rheology and by critical gel point study. The hydrogen bonding and the chemical interaction between PMVE-MA and PVA resulted in highly cross-linked membranes. Effect of the molecular weight of PVA on the membrane properties was also examined. The developed membranes were extensively characterized by studying their physicochemical properties (water uptake, swelling ratio, and conductivity), thermal and electrochemical properties using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermo-gravimetric analysis (TGA) and electrochemical impedance spectroscopy (EIS). The DSC study shows the presence of a single Tg in the membranes indicating compatibility of the two polymers in flexible and transparent films. The membranes show good stability and ion conductivity suitable for separator applications. PMID:28347019

  8. Influence of the brewing process on furfuryl ethyl ether formation during beer aging.

    PubMed

    Vanderhaegen, Bart; Neven, Hedwig; Verstrepen, Kevin J; Delvaux, Freddy R; Verachtert, Hubert; Derdelinckx, Guy

    2004-11-03

    In beer, the development of a solvent-like stale flavor is associated with the formation of furfuryl ethyl ether. The synthesis rate of this important flavor compound is proportional to the concentration of furfuryl alcohol in beer. This study shows that furfuryl alcohol in beer is mainly formed by Maillard reactions initiated during wort boiling and malt production. A mechanism for its formation from alpha-(1,4)-oligoglucans and amino acids in wort and beer is proposed. During wort boiling, a quadratic relationship was found between the wort extract concentration, on the one hand, and the increase of furfuryl alcohol and furfural, on the other. The reduction of furfural by yeast during fermentation further increases the furfuryl alcohol content. In pale beers, the furfuryl alcohol concentration is essentially determined by the thermal load on wort during brewing operations. In dark beers, a considerable fraction of furfuryl alcohol may, however, come from the dark malts used. These results lead to important practical conclusions concerning the control over furfuryl ethyl ether in beer.

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

    PubMed

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

    2015-10-01

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

  10. Reactivity of vinyl ethers and vinyl ribosides in UV-initiated free radical copolymerization with acceptor monomers.

    PubMed

    Pichavant, Loic; Guillermain, Céline; Coqueret, Xavier

    2010-09-13

    The reactivity of various vinyl ethers and vinyloxy derivatives of ribose in the presence of diethyl fumarate or diethyl maleate was investigated for evaluating the potential of donor-acceptor-type copolymerization applied to unsaturated monomers derived from renewable feedstock. The photochemically induced polymerization of model monomer blends in the bulk state was monitored by infrared spectroscopy. The method allowed us to examine the influence of monomer pair structure on the kinetic profiles. The simultaneous consumption of both monomers was observed, supporting an alternating copolymerization mechanism. A lower reactivity of the blends containing maleates compared with fumarates was confirmed. The obtained kinetic data revealed a general correlation between the initial polymerization rate and the Hansen parameter δ(H) associated with the H-bonding aptitude of the donor monomer.

  11. Synchrotron Photoionization Investigation of the Oxidation of Ethyl tert-Butyl Ether.

    PubMed

    Winfough, Matthew; Yao, Rong; Ng, Martin; Catani, Katherine; Meloni, Giovanni

    2017-02-23

    The oxidation of ethyl tert-butyl ether (ETBE), a widely used fuel oxygenated additive, is investigated using Cl atoms as initiators in the presence of oxygen. The reaction is carried out at 293, 550, and 700 K. Reaction products are probed by a multiplexed chemical kinetics photoionization mass spectrometer coupled with the synchrotron radiation produced at the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory. Products are identified on the basis of mass-to-charge ratio, ionization energies, and shape of photoionization spectra. Reaction pathways are proposed together with detected primary products.

  12. Poly(vinyl methyl ether) hydrogels at temperatures below the freezing point of water-molecular interactions and states of water.

    PubMed

    Pastorczak, Marcin; Dominguez-Espinosa, Gustavo; Okrasa, Lidia; Pyda, Marek; Kozanecki, Marcin; Kadlubowski, Slawomir; Rosiak, Janusz M; Ulanski, Jacek

    2014-01-01

    Water interacting with a polymer reveals a number of properties very different to bulk water. These interactions lead to the redistribution of hydrogen bonds in water. It results in modification of thermodynamic properties of water and the molecular dynamics of water. That kind of water is particularly well observable at temperatures below the freezing point of water, when the bulk water crystallizes. In this work, we determine the amount of water bound to the polymer and of the so-called pre-melting water in poly(vinyl methyl ether) hydrogels with the use of Raman spectroscopy, dielectric spectroscopy, and calorimetry. This analysis allows us to compare various physical properties of the bulk and the pre-melting water. We also postulate the molecular mechanism responsible for the pre-melting of part of water in poly(vinyl methyl ether) hydrogels. We suggest that above -60 °C, the first segmental motions of the polymer chain are activated, which trigger the process of the pre-melting.

  13. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Etbe) ...

    EPA Pesticide Factsheets

    In September 2016, the U.S. Environmental Protection Agency's (USEPA) released the draft Integrated Risk Information System (IRIS) Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE). Consistent with the 2013 IRIS Enhancements, draft IRIS assessments are released prior to external peer review for a 60-day public comment period and discussed at an upcoming public science meeting. Accordingly, the toxicological review, supplementary information, and other materials pertaining to this draft assessment are posted on this site. This material is being released for public viewing and comment prior to a public meeting, providing an opportunity for the IRIS Program to engage in early discussions with stakeholders and the public on data that may be used to identify adverse health effects and characterize exposure-response relationships.

  14. [Questions on the first operation with ethyl ether as anaesthetic by Dr. Peter Parker].

    PubMed

    Chen, Q

    2017-01-28

    Ethyl ether was the first accepted effective general anaesthetic. It was introduced into China by an America missionary, Dr. Peter Parker. This was one of the historical events of medical communication between China and the West. In the records of the first operation with ether, however, Dr. Parker unusually omitted the patient's medical record number and the date of the operation, while those of other operations with ether anesthetics were all available. This was very unusual for a doctor like Peter Parker who always recorded every important case in detail in the hospital reports. It seems that he deliberately rather than carelessly omitted the information for some reasons. Based on the analysis of Parker's reports, a conclusion is made that the anesthetic effect of the case was actually ineffective. Furthermore, possible answers to this are outlined and question by discussion based on the situation that Parker faced in the late Qing era.

  15. Searching for trans ethyl methyl ether in Orion KL★,★★

    PubMed Central

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

    2015-01-01

    We report on the tentative detection of trans ethyl methyl ether (tEME), t-CH3CH2OCH3, through the identification of a large number of rotational lines from each one of the spin states of the molecule towards Orion KL. We also search for gauche-trans-n-propanol, Gt-n-CH3CH2CH2OH, an isomer of tEME in the same source. We have identified lines of both species in the IRAM 30 m line survey and in the ALMA Science Verification data. We have obtained ALMA maps to establish the spatial distribution of these species. Whereas tEME mainly arises from the compact ridge component of Orion, Gt-n-propanol appears at the emission peak of ethanol (south hot core). The derived column densities of these species at the location of their emission peaks are ≤(4.0 ± 0.8) × 1015 cm−2 and ≤(1.0 ± 0.2)× 1015 cm−2 for tEME and Gt-n-propanol, respectively. The rotational temperature is ~100 K for both molecules. We also provide maps of CH3OCOH, CH3CH2OCOH, CH3OCH3, CH3OH, and CH3CH2OH to compare the distribution of these organic saturated O-bearing species containing methyl and ethyl groups in this region. Abundance ratios of related species and upper limits to the abundances of non-detected ethers are provided. We derive an abundance ratio N(CH3OCH3)/N(tEME) ≥ 150 in the compact ridge of Orion. PMID:26869726

  16. A Tetrazine-Labile Vinyl Ether Benzyloxycarbonyl Protecting Group (VeZ): An Orthogonal Tool for Solid-Phase Peptide Chemistry.

    PubMed

    Staderini, Matteo; Gambardella, Alessia; Lilienkampf, Annamaria; Bradley, Mark

    2018-06-01

    The vinyl ether benzyloxycarbonyl (VeZ) protecting group is selectively cleaved by treatment with tetrazines via an inverse electron-demand Diels-Alder reaction. This represents a new orthogonal protecting group for solid-phase peptide synthesis, with Fmoc-Lys(VeZ)-OH as a versatile alternative to Fmoc-Lys(Alloc)-OH and Fmoc-Lys(Dde)-OH, as demonstrated by the synthesis of two biologically relevant cyclic peptides.

  17. Thermodynamic and Kinetic Behavior of the Polystyrene/Poly(vinyl methyl ether) Blend as Studied by Excimer Fluorescence.

    DTIC Science & Technology

    1986-01-02

    AD-A±63 895 THERMODYNAMIC AND KINETIC BEHAVIOR OF THE / POLYSTYRENE/POLY(YINYL METHYL E..(U) STANFORD UNIY CALIFDEPT OF CHEMICAL ENGINEERING C N...Polystyrene/Poly(vinyl methyl ether) Blend 7. DEcFRMN 81 toOR 30USptE8 00~ as Studied by Excimer Fluorescence 6 EFRIGOG EOTNME *AUTHOR() a. CONTRACT OR GRANT...werea fondoare ihemoriisof * ~ Ex e sp fluodecositionsdu to deud Gen e and hoog Pinus Florsneis shownhase migrationprocSECURITY CLASIFICTIO OFd

  18. Searching for trans ethyl methyl ether in Orion KL⋆

    NASA Astrophysics Data System (ADS)

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

    2015-10-01

    We report on the tentative detection of trans ethyl methyl ether (tEME), t-CH3CH2OCH3, through the identification of a large number of rotational lines from each one of the spin states of the molecule towards Orion KL. We also search for gauche-trans-n-propanol, Gt-n-CH3CH2CH2OH, an isomer of tEME in the same source. We have identified lines of both species in the IRAM 30 m line survey and in the ALMA Science Verification data. We have obtained ALMA maps to establish the spatial distribution of these species. Whereas tEME mainly arises from the compact ridge component of Orion, Gt-n-propanol appears at the emission peak of ethanol (south hot core). The derived column densities of these species at the location of their emission peaks are ≤(4.0 ± 0.8) × 1015 cm-2 and ≤(1.0 ± 0.2) × 1015 cm-2 for tEME and Gt-n-propanol, respectively. The rotational temperature is ~100 K for both molecules. We also provide maps of CH3OCOH, CH3CH2OCOH, CH3OCH3, CH3OH, and CH3CH2OH to compare the distribution of these organic saturated O-bearing species containing methyl and ethyl groups in this region. Abundance ratios of related species and upper limits to the abundances of non-detected ethers are provided. We derive an abundance ratio N(CH3OCH3)/N(tEME) ≥ 150 in the compact ridge of Orion. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2011.0.00009.SV. ALMA is a partnership of ESO (representing its member states), NSF (USA), and NINS (Japan) with NRC (Canada), NSC, and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO, and NAOJ. This work was also based on observations carried out with the IRAM 30-m telescope. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain).Appendix A is available in electronic form at http://www.aanda.org

  19. DFT study on the adsorption of diethyl, ethyl methyl, and dimethyl ethers on the surface of gallium doped graphene

    NASA Astrophysics Data System (ADS)

    Shokuhi Rad, Ali; Sani, Emad; Binaeian, Ehsan; Peyravi, Majid; Jahanshahi, Mohsen

    2017-04-01

    In this study, we used density functional theory (DFT) to search on the adsorption properties of three important compounds of ether family; diethyl ether (DEE), ethyl methyl ether (EME), and dimethyl ether (DME) on the surface of Gallium doped graphene (GaG). We used three functionals (B3LYP, wb97xd, and MPW1PW91) for optimization and calculation of adsorption energy. After fully optimization, we scrutinized on the charge allocations on the adsorbed ethers as well as GaG (at the area of interaction) based on natural bond orbitals (NBO). Besides, we have calculated the amount of charge transfer upon adsorption of each analyte. We revel that GaG is an ideal adsorbent for chemisorption of all above-mentioned ethers. There is a little difference between the values of adsorption; -123.5, -120, and -118.3 kJ/mol (based on wb97xd) for DEE, EME, and DME, respectively. We found significant changes in the electronic structure of both adsorbent and adsorbate upon adsorption. Moreover, results of charge analyses confirm GaG is a p-type semiconductor.

  20. Sulfonated poly(ether ether ketone)/poly(vinyl alcohol) sensitizing system for solution photogeneration of small Ag, Au, and Cu crystallites.

    PubMed

    Korchev, A S; Shulyak, T S; Slaten, B L; Gale, W F; Mills, G

    2005-04-28

    Illumination of air-free aqueous solutions containing sulfonated poly(ether ether ketone) and poly(vinyl alcohol) with 350 nm light results in benzophenone ketyl radicals of the polyketone. The polymer radicals form with a quantum yield 0.02 and decay with a second-order rate constant 6 orders of magnitude lower than that of typical alpha-hydroxy radicals. Evidence is presented that the polymeric benzophenone ketyl radicals reduce Ag+, Cu2+, and AuCl4- to metal particles of nanometer dimensions. Decreases in the reduction rates with increasing Ag(I), Cu(II), and Au(III) concentrations are explained using a kinetic model in which the metal ions quench the excited state of the polymeric benzophenone groups, which forms the macromolecular radicals. Quenching is fastest for Ag+, whereas Cu2+ and AuCl4- exhibit similar rate constants. Particle formation becomes more complex as the number of equivalents needed to reduce the metal ions increases; the Au(III) system is an extreme case where the radical reactions operate in parallel with secondary light-initiated and thermal reduction channels. For each metal ion, the polymer-initiated photoreactions produce crystallites possessing distinct properties, such as a very strong plasmon in the Ag case or the narrow size distribution exhibited by Au particles.

  1. Effect of fluorinated groups on photooxidative stability of polymeric protectives applied on marble.

    PubMed

    Chiantore, O; Poli, T; Colombo, C; Peruzzi, R; Toniolo, L

    2001-01-01

    Some new protective copolymers and a commercial one have been tested on Candoglia marble, a very low porosity stone. Two of the polymers contained a partially fluorinated methacrylic monomer, 2,2,2 trifluoro ethyl methacrylate (TFEMA), in combination with either an acrylic, methyl acrylate (MA) or a vinyl ether, n-butyl vinyl ether (n-BVE) unit. Two copolymers, ethyl methacrylate/n-butyl vinyl ether and ethyl methacrylate (EMA)/methyl acrylate (Paraloid B72), were non-fluorinated and similar in compositions and molar ratio. The aim of the work is to test the copolymers and compare the performances of fluorinated new polymers with the non fluorinated one and with the largely used commercial product. The results obtained demonstrate that the introduction, even in limited amounts, of fluorine atoms in the side ester groups of methacrylic type polymers really improves their protective effect and the durability of the stone treatments. The best results were obtained with the copolymer TFEM/MA which is the fluorinated homologous of Paraloid B72.

  2. Microwave Spectroscopy of Trans-Ethyl Methyl Ether in the Ground State

    NASA Astrophysics Data System (ADS)

    Kobayashi, Kaori; Sakai, Yusuke; Tsunekawa, Shozo; Miyamoto, Taihei; Fujitake, Masaharu; Ohashi, Nobukimi

    2013-06-01

    The trans-ethyl methyl ether molecule (CH_3CH_2OCH_3) has two inequivalent methyl group internal rotors which corresponds to the two vibrational motions, ν_{28} and ν_{29}. Due to these internal rotations, a rotational transition could be split into maximum five components. The skeletal torsion (ν_{30}) is another low-lying state (ν_{30}) that interacts with the ν_{28} and ν_{29} modes. The microwave spectra of the trans-ethyl methyl ether molecule in the ν_{28} = 1, ν_{29} = 1, and ν_{30} = 1, 2 and 3 have been extensively studied by using Hougen's tunneling matrix formalism. The microwave spectroscopy in the ground state was studied by several groups. The splitting due to the ν_{28} mode (C-CH_3 internal rotation) is small in the ground state and was not fully resolved in most of the previous studied rotational transitions. In this paper, we report the results of the pulsed nozzle-jet Fourier transform microwave spectroscopy so as to measure the fully resolved spectra. The submillmeter wave spectroscopy was also carried out. Our analysis including the previously reported transitions would be useful for astronomical observations. K. Kobayashi, T. Matsui, N. Mori, S. Tsunekawa, and N. Ohashi J. Mol. Spectrosc. {269}, 242 2011. K. Kobayashi, T. Matsui, S. Tsunekawa, and N. Ohashi J. Mol. Spectrosc. {255}, 164 2009. K. Kobayashi, T. Matsui, N. Mori, S. Tsunekawa, and N. Ohashi J. Mol. Spectrosc.{251}, 301 2008. K. Kobayashi, K. Murata, S. Tsunekawa, and N. Ohashi Int. Symposium on Mol. Spectrosc., 65th Meeting TH15 2010.} M. Hayashi, and K. Kuwada J. Mol. Structure {28}, 147 1975. M. Hayashi, and M. Adachi J. Mol. Structure {78}, 53 1982. S. Tsunekawa, Y. Kinai, Y. Kondo, H. Odashima, and K. Takagi Molecules {8}, 103 2003. U. Fuchs, G. Winnewisser, P. Groner, F. C. De Lucia, and E. Herbst Astrophys. J. Suppl. {144}, 277 2003.

  3. Mild copper-catalyzed vinylation reactions of azoles and phenols with vinyl bromides.

    PubMed

    Taillefer, Marc; Ouali, Armelle; Renard, Brice; Spindler, Jean-Francis

    2006-07-05

    An efficient and straightforward copper-catalyzed method allowing vinylation of N- or O-nucleophiles with di- or trisubstituted vinyl bromides is reported. The procedure is applicable to a broad range of substrates since N-vinylation of mono-, di-, and triazoles as well as O-vinylation of phenol derivatives can be performed with catalytic amounts of copper iodide and inexpensive nitrogen ligands 3 or 8. In the case of more hindered vinyl bromides, the use of the original bidentate chelator 8 was shown to be more efficient to promote the coupling reactions than our key tetradentate ligand 3. The corresponding N-(1-alkenyl)azoles and alkenyl aryl ethers are obtained in high yields and selectivities under very mild temperature conditions (35-110 degrees C for N-vinylation reactions and 50-80 degrees C for O-vinylation reactions). Moreover, to our knowledge, this method is the first example of a copper-catalyzed vinylation of various azoles. Finally, this protocol, practical on a laboratory scale and easily adaptable to an industrial scale, is very competitive compared to the existing methods that allow the synthesis of such compounds.

  4. Effect of chain structure on hydrogen bonding in vinyl acetate - vinyl alcohol copolymers

    NASA Astrophysics Data System (ADS)

    Merekalova, Nadezhda D.; Bondarenko, Galina N.; Denisova, Yuliya I.; Krentsel, Liya B.; Litmanovich, Arkadiy D.; Kudryavtsev, Yaroslav V.

    2017-04-01

    FTIR spectroscopy and semi-empirical AM1 method are used to study hydrogen bonding in multiblock and random equimolar copolymers of vinyl acetate and vinyl alcohol. An energetically beneficial zip-holder complex, built on multiple inter- and intrachain hydroxyl-hydroxyl bonds and an intrachain hydroxyl-acetyloxy bond, can be formed between two vinyl alcohol sequences. As a result, multiblock copolymers reveal stronger degree of association that affects crystallinity, as well as various rheological and relaxation properties discussed in the literature. Macromolecular complexes in random copolymers are weak and tend to be destroyed in the presence of residual DMF solvent and adsorbed water. Nevertheless, a rather stable interchain quaternary complex can be formed that includes vinyl alcohol and vinyl acetate units and DMF and water molecules. For a single chain it is shown that an H-bond between neighboring vinyl alcohol and vinyl acetate monomer units mostly engages a carbonyl oxygen atom of the vinyl acetate, if the vinyl alcohol belongs to a short (<5 units) sequence, and an ether oxygen atom in the other case. On the whole, the quantum chemistry calculations shed much light on the origin of distinctions in the copolymer FTIR spectra, which may seem subtle when considered standalone.

  5. Rotational Spectroscopy of Two Tellurol Compounds : Ethyl and Vinyl-Tellurol

    NASA Astrophysics Data System (ADS)

    Motiyenko, R.; Margulès, L.; Goubet, M.; Møllendal, H.; Guillemin, J. C.

    2009-06-01

    Among the compounds containing a chalcogen, the tellurols (R-TeH) have been poorly investigated previously. Only H_2Te was studied in rotational spectroscopy. This fact can be explained by high toxicity and high chemical reactivity of these compounds. However quite recently, a new method allowing easily obtention of pure samples has been reported. Thanks to this approach, very high acidity of these tellurols in gas phase has been measured and photoelectron spectra have been recorded. It should be noted that, even if simple derivatives are known since a long time, no microwave spectrum of these compounds has been recorded previously. The determination of their rotational constants is however a determining step to have a quite complete knowledge of such systems and to be able to perform comparisons of their physicochemical properties with those of the corresponding thiols and selenols which have been more extensively studied. The rotational spectra of vinyl and ethyl-tellurol have been recorded in the frequency range up to 210 GHz. For both compounds gauche forms have been assigned due to rather distinguishable patterns of a-type transitions. The assignments were confirmed by comparison with the results of ab initio calculations. For ethyl-tellurol the rotational transitions were observed as doublets. The splittings are probably caused by tunneling effect between two equivalent configurations (gauche^+, gauche^-). The assignment and analysis of the rotational spectra of both molecules is in progress. The latest results will be reported. I. N. Kozin, P. Jensen, O. Polanz, S. Klee, L. Poteau, and J. Demaison, J. Mol. Spectrosc., 180 402-413 (1996) J. C. Guillemin, A. Bouayard, D. Vijaykumar, D. Chem. Commun., 1163-1164 (2000) J. C. Guillemin, El. H. Riague, J. F. Gal, P. C. Marris, O. Mo., M. Yanez, Chem. Eur. J. 11, 2145-2153 (2005) B. Khater, J. C. Guillemin, G. Bajor, T. Veszprémi, P. C. Marris, O. Mo., M. Yanez, Inorg. Chem. 112, 3053-3060 (2008) A. Baroni, Atti

  6. Trans-ethyl methyl ether, the struggle for the detection of a complex molecule in hot cores

    NASA Astrophysics Data System (ADS)

    Fuchs, G. W.; Fuchs, U.; Giesen, T. F.; Wyrowski, F.

    Many large and complex molecules of prebiotic importance have been found as constituents of interstellar clouds but their detection remains difficult and sometimes doubtful (Snyder et al. 2005). The complex spectrum of trans-ethyl methyl ether (EME) has been investigated in the laboratory (Fuchs et al. 2003) up to 350 GHz and is now known with high frequency precision, see Figure 1. In this work we present an extensive search for EME towards G34.26, NGC6334(I), Orion KL, SgrB2(N) and W51e2 in the 1 to 3 mm wavelength region. These sources have previously been shown to have a rich chemistry of complex molecules. The IRAM 30m telescope at Pico Veleta, Spain and the SEST 15m radio telescope in La Silla, Chile have been used for the observations. We looked at 5 - 11 frequency bands where EME has strong transitions. All sources were examined using long integration times up to 220 min (on+off), elevations greater 40◦ and under good weather conditions. For our analysis of the data we used the method of rotational-temperature-diagrams but also the myXCLASS (written by Peter Schilke) extension program to the GILDAS (Grenoble Image and Line Data Analysis Software) software which enabled us to simulate spectra of several molecules including their linewidth and intensities at the same time, see Figure 2. With this program a consistency check of molecular abundances and overall composition is possible even in dense spectra with many overlapping lines. The effect of the source size on the measured intensities has been considered and cross checks with other important molecules such as methanol, ethanol and di-methyl ether have been performed. Charnley et al. (2001) assigned one line in W51 e1/e2 and one line in Orion KL at 160.1 GHz, as well as a line in SgrB2(N) at 79.6 GHz to trans-ethyl methyl ether. From their isolated measurements, the column density of EME was estimated to be in the range 1014-1015 cm-2 in Sgr B2(N) corresponding to a fractional abundance of 10

  7. Thermodynamic equilibrium calculations of dimethyl ether steam reforming and dimethyl ether hydrolysis

    NASA Astrophysics Data System (ADS)

    Semelsberger, Troy A.; Borup, Rodney L.

    The production of a hydrogen-rich fuel-cell feed by dimethyl ether (DME) steam reforming was investigated using calculations of thermodynamic equilibrium as a function of steam-to-carbon ratio (0.00-4.00), temperature (100-600 °C), pressure (1-5 atm), and product species. Species considered were acetone, acetylene, carbon dioxide, carbon monoxide, dimethyl ether, ethane, ethanol, ethylene, formaldehyde, formic acid, hydrogen, isopropanol, methane, methanol, methyl-ethyl ether, n-propanol and water. Thermodynamic equilibrium calculations of DME steam reforming indicate complete conversion of dimethyl ether to hydrogen, carbon monoxide and carbon dioxide at temperatures greater than 200 °C and steam-to-carbon ratios greater than 1.25 at atmospheric pressure ( P = 1 atm). Increasing the operating pressure shifts the equilibrium toward the reactants; increasing the pressure from 1 to 5 atm decreases the conversion of dimethyl ether from 99.5 to 76.2%. The trend of thermodynamically stable products in decreasing mole fraction is methane, ethane, isopropyl alcohol, acetone, n-propanol, ethylene, ethanol, methyl-ethyl ether and methanol-formaldehyde, formic acid, and acetylene were not observed. Based on the equilibrium calculations, the optimal processing conditions for dimethyl ether steam reforming occur at a steam-to-carbon ratio of 1.50, a pressure of 1 atm, and a temperature of 200 °C. These thermodynamic equilibrium calculations show dimethyl ether processed with steam will produce hydrogen-rich fuel-cell feeds—with hydrogen concentrations exceeding 70%. The conversion of dimethyl ether via hydrolysis (considering methanol as the only product) is limited by thermodynamic equilibrium. Equilibrium conversion increases with temperature and steam-to-carbon ratio. A maximum dimethyl ether conversion of 62% is achieved at a steam-to-carbon ratio of 5.00 and a processing temperature of 600 °C.

  8. 21 CFR 573.420 - Ethyl cellulose.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.420 Ethyl cellulose. The food additive ethyl cellulose may be safely used in animal feed in accordance with the following prescribed conditions: (a) The food additive is a cellulose ether containing...

  9. 21 CFR 573.420 - Ethyl cellulose.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.420 Ethyl cellulose. The food additive ethyl cellulose may be safely used in animal feed in accordance with the following prescribed conditions: (a) The food additive is a cellulose ether containing...

  10. 21 CFR 573.420 - Ethyl cellulose.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.420 Ethyl cellulose. The food additive ethyl cellulose may be safely used in animal feed in accordance with the following prescribed conditions: (a) The food additive is a cellulose ether containing...

  11. 21 CFR 573.420 - Ethyl cellulose.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.420 Ethyl cellulose. The food additive ethyl cellulose may be safely used in animal feed in accordance with the following prescribed conditions: (a) The food additive is a cellulose ether containing...

  12. 21 CFR 573.420 - Ethyl cellulose.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.420 Ethyl cellulose. The food additive ethyl cellulose may be safely used in animal feed in accordance with the following prescribed conditions: (a) The food additive is a cellulose ether containing...

  13. NIOSH Manual of Analytical Methods (third edition). Fourth supplement

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1990-08-15

    The NIOSH Manual of Analytical Methods, 3rd edition, was updated for the following chemicals: allyl-glycidyl-ether, 2-aminopyridine, aspartame, bromine, chlorine, n-butylamine, n-butyl-glycidyl-ether, carbon-dioxide, carbon-monoxide, chlorinated-camphene, chloroacetaldehyde, p-chlorophenol, crotonaldehyde, 1,1-dimethylhydrazine, dinitro-o-cresol, ethyl-acetate, ethyl-formate, ethylenimine, sodium-fluoride, hydrogen-fluoride, cryolite, sodium-hexafluoroaluminate, formic-acid, hexachlorobutadiene, hydrogen-cyanide, hydrogen-sulfide, isopropyl-acetate, isopropyl-ether, isopropyl-glycidyl-ether, lead, lead-oxide, maleic-anhydride, methyl-acetate, methyl-acrylate, methyl-tert-butyl ether, methyl-cellosolve-acetate, methylcyclohexanol, 4,4'-methylenedianiline, monomethylaniline, monomethylhydrazine, nitric-oxide, p-nitroaniline, phenyl-ether, phenyl-ether-biphenyl mixture, phenyl-glycidyl-ether, phenylhydrazine, phosphine, ronnel, sulfuryl-fluoride, talc, tributyl-phosphate, 1,1,2-trichloro-1,2,2-trifluoroethane, trimellitic-anhydride, triorthocresyl-phosphate, triphenyl-phosphate, and vinyl-acetate.

  14. Millimeter Wave Spectrum and Astronomical Search for Vinyl Formate

    NASA Astrophysics Data System (ADS)

    Alonso, E. R.; Kolesniková, L.; Tercero, B.; Cabezas, C.; Alonso, J. L.; Cernicharo, J.; Guillemin, J.-C.

    2016-11-01

    Previous detections of methyl and ethyl formate make other small substituted formates potential candidates for observation in the interstellar medium. Among them, vinyl formate is one of the simplest unsaturated carboxylic ester. The aim of this work is to provide direct experimental frequencies of the ground vibrational state of vinyl formate in a large spectral range for astrophysical use. The room-temperature rotational spectrum of vinyl formate has been measured from 80 to 360 GHz and analyzed in terms of Watson’s semirigid rotor Hamiltonian. Two thousand six hundred transitions within J = 3-88 and K a = 0-28 were assigned to the most stable conformer of vinyl formate and a new set of spectroscopic constants was accurately determined. Spectral features of vinyl formate were then searched for in Orion KL, Sgr B2(N), B1-b, and TMC-1 molecular clouds. Upper limits to the column density of vinyl formate are provided.

  15. MILLIMETER WAVE SPECTRUM AND ASTRONOMICAL SEARCH FOR VINYL FORMATE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Alonso, E. R.; Kolesniková, L.; Cabezas, C.

    2016-11-20

    Previous detections of methyl and ethyl formate make other small substituted formates potential candidates for observation in the interstellar medium. Among them, vinyl formate is one of the simplest unsaturated carboxylic ester. The aim of this work is to provide direct experimental frequencies of the ground vibrational state of vinyl formate in a large spectral range for astrophysical use. The room-temperature rotational spectrum of vinyl formate has been measured from 80 to 360 GHz and analyzed in terms of Watson’s semirigid rotor Hamiltonian. Two thousand six hundred transitions within J = 3–88 and K {sub a} = 0–28 were assignedmore » to the most stable conformer of vinyl formate and a new set of spectroscopic constants was accurately determined. Spectral features of vinyl formate were then searched for in Orion KL, Sgr B2(N), B1-b, and TMC-1 molecular clouds. Upper limits to the column density of vinyl formate are provided.« less

  16. CF3+ fragmentation by electron impact ionization of perfluoro-propyl-vinyl-ethers, C5F10O, in gas phase

    NASA Astrophysics Data System (ADS)

    Kondo, Yusuke; Ishikawa, Kenji; Hayashi, Toshio; Miyawaki, Yudai; Takeda, Keigo; Kondo, Hiroki; Sekine, Makoto; Hori, Masaru

    2015-04-01

    The gas phase fragmentations of perfluoro-propyl-vinyl ether (PPVE, C5F10O) are studied experimentally. Dominant fragmentations of PPVE are found to be the result of a dissociative ionization reaction, i.e., CF3+ via direct bond cleavage, and C2F3O- and C3F7O- via electron attachment. Regardless of the appearance energy of around 14.5 eV for the dissociative ionization of CF3+, the observed ion efficiency for the CF3+ ion was extremely large the order of 10-20 cm-2, compared with only 10-21 cm-2 for the other channels. PPVE characteristically generated CF3+ as the largest abundant ion are advantageous for use of feedstock gases in plasma etching processes.

  17. Toxic effect and genotoxicity of the semisynthetic derivatives dillapiole ethyl ether and dillapiole n-butyl ether for control of Aedes albopictus (Diptera: Culicidae).

    PubMed

    da Fonseca Meireles, Sabrina; Domingos, Pedro Rauel Cândido; da Silva Pinto, Ana Cristina; Rafael, Míriam Silva

    2016-09-01

    Two derivatives of dillapiole, dillapiole ethyl ether (1KL39-B) and butyl ether-n dillapiole (1KL43-C), were studied for their toxicity and genotoxicity against Aedes albopictus, to help develop new strategies for the control of this potential vector of dengue and other arboviruses, because it is resistant to synthetic insecticides. Eggs and larvae exposed to different concentrations of 1KL39-B (25, 30, 50, 70, and 80μg/mL) and of 1KL43-C (12.5, 20, 25, 30 and 40μg/mL) exhibited toxicity and susceptibility, with 100% mortality. The LC50 was 55.86±1.57μg/mL for 1KL39-B and 25.60±1.24μg/mL for 1KL43-C, while the LC90 was 70.12μg/mL for 1KL39-B and 41.51μg/mL for 1KL43-C. The gradual decrease in oviposition of the females of the G1 to G4 generations was proportional to the increase in concentrations of these compounds, which could be related to the cumulative effect of cell anomalies in neuroblasts and oocytes (P<0.05), including micronuclei, budding, multinucleated cells and nuclear bridges. These findings showed that both 1KL39-B and 1KL43-C can serve as potential alternatives in the control of A. albopictus. Copyright © 2016. Published by Elsevier B.V.

  18. Behaviour of solid phase ethyl cyanide in simulated conditions of Titan

    NASA Astrophysics Data System (ADS)

    Couturier-Tamburelli, I.; Toumi, A.; Piétri, N.; Chiavassa, T.

    2018-01-01

    In order to simulate different altitudes in the atmosphere of Titan, we investigated using infrared spectrometry and mass spectrometry the photochemistry of ethyl cyanide (CH3CH2CN) ices at different temperatures. Heating experiments of the solid phase until complete desorption showed up three phase transitions with a first one appearing to be approximately at the temperature of Titan's surface (94 K), measured by the Huygens probe. Ethyl cyanide, whose presence has been suggested in solid phase in Titan, can be considered as another nitrile for photochemical models of the Titan atmosphere after our first study (Toumi et al., 2016) concerning vinyl cyanide (CH2CHCN). The desorption energy of ethyl cyanide has been calculated to be 36.75 ( ± 0.55) kJ mol-1 using IRTF and mass spectroscopical techniques. High energetic photolysis (λ > 120 nm) have been performed and we identified ethyl isocyanide, vinyl cyanide, cyanoacetylene, ethylene, acetylene, cyanhydric acid and a methylketenimine form as photoproducts from ethyl cyanide. The branching ratios of the primary products were determined at characteristic temperatures of Titan thanks to the value of the νCN stretching band strength of ethyl cyanide that has been calculated to be 4.12 × 10-18 cm molecule-1. We also report here for the first time the values of the photodissociation cross sections of C2H5CN for different temperatures.

  19. Poly(methyl vinyl ether-alt-maleic acid)-functionalized porous silicon nanoparticles for enhanced stability and cellular internalization.

    PubMed

    Shahbazi, Mohammad-Ali; Almeida, Patrick V; Mäkilä, Ermei; Correia, Alexandra; Ferreira, Mónica P A; Kaasalainen, Martti; Salonen, Jarno; Hirvonen, Jouni; Santos, Hélder A

    2014-03-01

    Currently, developing a stable nanocarrier with high cellular internalization and low toxicity is a key bottleneck in nanomedicine. Here, we have developed a successful method to covalently conjugate poly(methyl vinyl ether-co-maleic acid) (PMVE-MA) copolymer on the surface of (3-aminopropyl)triethoxysilane-functionalized thermally carbonized porous silicon nanoparticles (APSTCPSi NPs), forming a surface negatively charged nanovehicle with unique properties. This polymer conjugated NPs could modify surface smoothness, charge, and hydrophilicity of the developed NPs, leading to considerable improvement in the colloidal and plasma stabilities via enhanced suspensibility and charge repulsion. Furthermore, despite the surface negative charge of the polymer-conjugated NPs, the cellular internalization was increased in both MDA-MB-231 and MCF-7 breast cancer cells. These results provide a proof-of-concept evidence that such polymer-based PSi nanocomposite can be extensively used as a promising candidate for intracellular drug delivery. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Anti-knock quality of sugar derived levulinic esters and cyclic ethers

    DOE PAGES

    Tian, Miao; McCormick, Robert L.; Luecke, Jon; ...

    2017-04-22

    Here, the objective of this paper is to investigate the anti-knock quality of sugar-derived levulinic esters (methyl levulinate (ML) and ethyl levulinate (EL)) and cyclic ethers (furfuryl ethyl ether (FEE) and ethyl tetrahydrofurfuryl ether (ETE)). To this end, combustion experiments were carried out in both an engine and a constant volume autoignition device. The results from both apparati demonstrate that ML, EL and FEE have superior anti-knock quality than the reference Euro95 gasoline. ETE, conversely, performed markedly worse than the reference fuel on both setups and might therefore be a more appropriate fuel for compression ignition engines. The main reasonmore » of the distinctions in anti-knock quality can be found in the molecular structure of the neat biofuels. ML and EL are levulinic esters, with a ketone (C=O) functionality and an ester (C(=O)-O) group on the carbon chain. They can readily produce stable intermediates during the auto-ignition process, thereby slowing down the overall reaction rate. The unsaturated cyclic ether (FEE) has very strong ring C-H bonds. However, the saturated cyclic ether (ETE) has weak ring C-H bonds, which facilitate more readily ring opening reactions. Long side chains on the cyclic ethers further accelerate the reaction rate. Importantly for future research, our results suggest that IQT and engine experiments are interchangeable setups with respect to qualitative anti-knock quality evaluation of novel compounds.« less

  1. Anti-knock quality of sugar derived levulinic esters and cyclic ethers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tian, Miao; McCormick, Robert L.; Luecke, Jon

    Here, the objective of this paper is to investigate the anti-knock quality of sugar-derived levulinic esters (methyl levulinate (ML) and ethyl levulinate (EL)) and cyclic ethers (furfuryl ethyl ether (FEE) and ethyl tetrahydrofurfuryl ether (ETE)). To this end, combustion experiments were carried out in both an engine and a constant volume autoignition device. The results from both apparati demonstrate that ML, EL and FEE have superior anti-knock quality than the reference Euro95 gasoline. ETE, conversely, performed markedly worse than the reference fuel on both setups and might therefore be a more appropriate fuel for compression ignition engines. The main reasonmore » of the distinctions in anti-knock quality can be found in the molecular structure of the neat biofuels. ML and EL are levulinic esters, with a ketone (C=O) functionality and an ester (C(=O)-O) group on the carbon chain. They can readily produce stable intermediates during the auto-ignition process, thereby slowing down the overall reaction rate. The unsaturated cyclic ether (FEE) has very strong ring C-H bonds. However, the saturated cyclic ether (ETE) has weak ring C-H bonds, which facilitate more readily ring opening reactions. Long side chains on the cyclic ethers further accelerate the reaction rate. Importantly for future research, our results suggest that IQT and engine experiments are interchangeable setups with respect to qualitative anti-knock quality evaluation of novel compounds.« less

  2. Effects of a thirteen-week inhalation exposure to ethyl tertiary butyl ether on fischer-344 rats and CD-1 mice.

    PubMed

    Medinsky, M A; Wolf, D C; Cattley, R C; Wong, B; Janszen, D B; Farris, G M; Wright, G A; Bond, J A

    1999-09-01

    The 1990 Clean Air Act Amendments require that oxygenates be added to automotive fuels to reduce emissions of carbon monoxide and hydrocarbons. One potential oxygenate is the aliphatic ether ethyl tertiary butyl ether (ETBE). Our objective was to provide data on the potential toxic effects of ETBE. Male and female Fisher 344 rats and CD-1 mice were exposed to 0 (control), 500, 1750, or 5000 ppm of ETBE for 6 h/day and 5 days/wk over a 13-week period. ETBE exposure had no effect on mortality and body weight with the exception of an increase in body weights of the female rats in the 5000-ppm group. No major changes in clinical pathology parameters were noted for either rats or mice exposed to ETBE for 6 (rats only) or 13 weeks. Liver weights increased with increasing ETBE-exposure concentration for both sexes of rats and mice. Increases in kidney, adrenal, and heart (females only) weights were noted in rats. Degenerative changes in testicular seminiferous tubules were observed in male rats exposed to 1750 and 5000 ppm but were not seen in mice. This testicular lesion has not been reported previously for aliphatic ethers. Increases in the incidence of regenerative foci, rates of renal cell proliferation, and alpha2u-globulin containing protein droplets were noted in the kidneys of all treated male rats. These lesions are associated with the male rat-specific syndrome of alpha2u-globulin nephropathy. Increases in the incidence of centrilobular hepatocyte hypertrophy and rates of hepatocyte cell proliferation were seen in the livers of male and female mice in the 5000-ppm group, consistent with a mitogenic response to ETBE. These two target organs for ETBE toxicity, mouse liver and male rat kidney, have also been reported for methyl tertiary butyl ether and unleaded gasoline.

  3. Design and synthesis of new adamantyl-substituted antileishmanial ether phospholipids.

    PubMed

    Papanastasiou, Ioannis; Prousis, Kyriakos C; Georgikopoulou, Kalliopi; Pavlidis, Theofilos; Scoulica, Effie; Kolocouris, Nicolas; Calogeropoulou, Theodora

    2010-09-15

    A series of new 2-[3-(2-alkyloxy-ethyl)-adamantan-1-yl]-ethoxy substituted ether phospholipids was synthesized and their antileishmanial activity was evaluated against Leishmania infantum amastigotes. The majority of the new analogues were significantly less cytotoxic than miltefosine while, antiparasitic activity depended on the length of the 2-alkyloxy substituent. The most potent compounds were {2-[[[3-(2-hexyloxy-ethyl)-adamant-1-yl]-ethoxy]hydroxyphosphinyloxy]ethyl}-Nu,Nu,Nu-trimethyl-ammonium inner salt (5b) and {2-[[[3-(2-octyloxy-ethyl)-adamant-1-yl]-ethoxy]hydroxyphosphinyloxy]ethyl}-Nu,Nu,Nu-trimethyl-ammonium inner salt (5c). Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  4. Ethyl tertiary-butyl ether: a toxicological review.

    PubMed

    McGregor, Douglas

    2007-05-01

    A number of oxygenated compounds (oxygenates) are available for use in gasoline to reduce vehicle exhaust emissions, reduce the aromatic compound content, and avoid the use of organo-lead compounds, while maintaining high octane numbers. Ethyl tertiary-butyl ether (ETBE) is one such compound. The current use of ETBE in gasoline or petrol is modest but increasing, with consequently similar trends in the potential for human exposure. Inhalation is the most likely mode of exposure, with about 30% of inhaled ETBE being retained by the lungs and distributed around the body. Following cessation of exposure, the blood concentration of ETBE falls rapidly, largely as a result of its metabolism to tertiary-butyl alcohol (TBA) and acetaldehyde. TBA may be further metabolized, first to 2-methyl-1,2-propanediol and then to 2-hydroxyisobutyrate, the two dominant metabolites found in urine of volunteers and rats. The rapid oxidation of acetaldehyde suggests that its blood concentration is unlikely to rise above normal as a result of human exposure to sources of ETBE. Single-dose toxicity tests show that ETBE has low toxicity and is essentially nonirritant to eyes and skin; it did not cause sensitization in a maximization test in guinea pigs. Neurological effects have been observed only at very high exposure concentrations. There is evidence for an effect of ETBE on the kidney of rats. Increases in kidney weight were seen in both sexes, but protein droplet accumulation (with alpha(2u)-globulin involvement) and sustained increases in cell proliferation occurred only in males. In liver, centrilobular necrosis was induced in mice, but not rats, after exposure by inhalation, although this lesion was reported in some rats exposed to very high oral doses of ETBE. The proportion of liver cells engaged in S-phase DNA synthesis was increased in mice of both sexes exposed by inhalation. ETBE has no specific effects on reproduction, development, or genetic material. Carcinogenicity studies

  5. Upper limits for the ethyl-cyanide abundances in TMC-1 and L134N - Chemical implications

    NASA Technical Reports Server (NTRS)

    Minh, Y. C.; Irvine, W. M.

    1991-01-01

    Interstellar ethyl-cyanide has been sought via its 2(02)-1(01) transition towards two cold, dark clouds, and upper limits of the total column densities of 3 x 10 to the 12th/sq cm and 2 x 10 to the 12th/sq cm for TMC-1 and L134N, respectively. The 2(02)-1(01) transition of vynil cyanide, previously identified in TMC-1 by Matthews and Sears (1983b), was also observed. The detection of vinyl cyanide and the nondetection of ethyl cyanide in TMC-1 are consistent with gas phase ion-molecule chemical models, and there is thus no necessity of invoking grain surface synthesis for vinyl cyanide in cold clouds.

  6. Toxicokinetics of ethers used as fuel oxygenates.

    PubMed

    Dekant, W; Bernauer, U; Rosner, E; Amberg, A

    2001-10-15

    The toxicokinetics and biotransformation of methyl-tert.butyl ether (MTBE), ethyl-tert.butyl ether (ETBE) and tert.amyl-methyl ether (TAME) in rats and humans are summarized. These ethers are used as gasoline additives in large amounts, and thus, a considerable potential for human exposure exists. After inhalation exposure MTBE, ETBE and TAME are rapidly taken up by both rats and humans; after termination of exposure, clearance by exhalation and biotransformation to urinary metabolites is rapid in rats. In humans, clearance by exhalation is slower in comparison to rats. Biotransformation of MTBE and ETBE is both qualitatively and quantitatively similar in humans and rats after inhalation exposure under identical conditions. The extent of biotransformation of TAME is also quantitatively similar in rats and humans; the metabolic pathways, however, are different. The results suggest that reactive and potentially toxic metabolites are not formed during biotransformation of these ethers and that toxic effects of these compounds initiated by covalent binding to cellular macromolecules are unlikely.

  7. Anionic polymer, poly(methyl vinyl ether-maleic anhydride)-coated beads-based capture of human influenza A and B virus.

    PubMed

    Sakudo, Akikazu; Baba, Koichi; Tsukamoto, Megumi; Sugimoto, Atsuko; Okada, Takashi; Kobayashi, Takanori; Kawashita, Norihito; Takagi, Tatsuya; Ikuta, Kazuyoshi

    2009-01-15

    An anionic magnetic beads-based method was developed for the capture of human influenza A and B viruses from nasal aspirates, allantoic fluid and culture medium. A polymer, poly(methyl vinyl ether-maleic anhydride) [poly(MVE-MA)], was used to endow magnetic beads with a negative charge and bioadhesive properties. After incubation with samples containing human influenza virus, the beads were separated from supernatants by applying a magnetic field. The adsorption [corrected] of the virus by the beads was confirmed by hemagglutinin assay, immunochromatography, Western blotting, egg infection, and cell infection. Successful capture was proved using 5 H1N1 influenza A viruses, 10 H3N2 influenza A viruses, and 6 influenza B viruses. Furthermore, the infectivity in chicken embryonated eggs and Madin-Darby canine kidney (MDCK) cells of the captured human influenza virus was similar to that of the total viral quantity of starting materials. Therefore, this method of capture using magnetic beads coated with poly(MVE-MA) can be broadly used for the recovery of infectious human influenza viruses.

  8. The formation of diethyl ether via the reaction of iodoethane with atomic oxygen on the Ag(110) surface

    NASA Astrophysics Data System (ADS)

    Jones, G. Scott; Barteau, Mark A.; Vohs, John M.

    1999-01-01

    The reactions of iodoethane (ICH 2CH 3) on clean and oxygen-covered Ag(110) surfaces were investigated using temperature-programmed desorption (TPD) and high-resolution electron energy-loss spectroscopy (HREELS). Iodoethane adsorbs dissociatively at 150 K to produce surface ethyl groups on both clean and oxygen-covered Ag(110) surfaces. The ethyl species couple to form butane on both surfaces, with the desorption peak maximum located between 218 and 238 K, depending on the ethyl coverage. In addition to butane, a number of oxidation products including diethyl ether, ethanol, acetaldehyde, surface acetate, ethylene, carbon dioxide and water were formed on the oxygen-dosed Ag(110) surface. Diethyl ether was the major oxygenate produced at all ethyl:oxygen ratios, and the peak temperature for ether evolution varied from 220 to 266 K depending on the relative coverages of these reactants. The total combustion products, CO 2 and H 2O, were primarily formed at low ethyl coverages in the presence of excess oxygen. The formation of ethylene near 240 K probably involves an oxygen-assisted dehydrogenation pathway since ethylene is not formed from ethyl groups on the clean surface. Acetaldehyde and ethanol evolve coincidentally with a peak centered at 270-280 K, and are attributed to the reactions of surface ethoxide species. The surface acetate which decomposes near 620 K is formed from subsequent reactions of acetaldehyde with oxygen atoms. The addition of ethyl to oxygen to form surface ethoxides was verified by HREELS results. The yields of all products exhibited a strong dependence on the relative coverages of ethyl and oxygen.

  9. Changes in chemical permeation of disposable latex, nitrile, and vinyl gloves exposed to simulated movement.

    PubMed

    Phalen, Robert N; Le, Thi; Wong, Weng Kee

    2014-01-01

    Glove movement can affect chemical permeation of organic compounds through polymer glove products. However, conflicting reports make it difficult to compare the effects of movement on chemical permeation through commonly available glove types. The aim of this study was to evaluate the effect of movement on chemical permeation of an organic solvent through disposable latex, nitrile, and vinyl gloves. Simulated whole-glove permeation testing was conducted using ethyl alcohol and a previously designed permeation test system. With exposure to movement, a significant decrease (p ≤ 0.001) in breakthrough time (BT) was observed for the latex (-23%) and nitrile gloves (-31%). With exposure to movement, only the nitrile glove exhibited a significant increase (p ≤ 0.001) in steady-state permeation rate (+47%) and cumulative permeation at 30 min (+111%). Even though the nitrile glove provided optimum chemical resistance against ethyl alcohol, it was most affected by movement. With exposure to movement, the latex glove was an equivalent option for overall worker protection, because it was less affected by movement and the permeation rate was lower than that of the nitrile glove. In contrast, the vinyl glove was the least affected by movement, but did not provide adequate chemical resistance to ethyl alcohol in comparison with the nitrile and latex gloves. Glove selection should take movement and polymer type into account. Some glove polymer types are less affected by movement, most notably the latex glove in this test. With nitrile gloves, at least a factor of three should be used when attempting to assign a protection factor when repetitive hand motions are anticipated. Ultimately, the latex gloves outperformed nitrile and vinyl in these tests, which evaluated the effect of movement on chemical permeation. Future research should aim to resolve some of the observed discrepancies in test results with latex and vinyl gloves.

  10. Changes in Chemical Permeation of Disposable Latex, Nitrile and Vinyl Gloves Exposed to Simulated Movement

    PubMed Central

    Phalen, Robert N.; Le, Thi; Wong, Weng Kee

    2014-01-01

    Glove movement can affect chemical permeation of organic compounds through polymer glove products. However, conflicting reports make it difficult to compare the effects of movement on chemical permeation through commonly available glove types. This study was aimed to evaluate the effect of movement on chemical permeation of an organic solvent through disposable latex, nitrile, and vinyl gloves. Simulated whole-glove permeation testing was conducted using ethyl alcohol and a previously designed permeation test system. With exposure to movement, a significant decrease (p ≤ 0.001) in breakthrough time was observed for the latex (-23%) and nitrile gloves (-31%). With exposure to movement, only the nitrile glove exhibited a significant increase (p ≤ 0.001) in steady-state permeation rate (+47%) and cumulative permeation at 30 min (+111%). Even though the nitrile glove provided optimum chemical resistance against ethyl alcohol, it was most affected by movement. With exposure to movement, the latex glove was an equivalent option for overall worker protection, because it was less affected by movement and the permeation rate was lower than that of the nitrile glove. In contrast, the vinyl glove was the least affected by movement, but did not provide adequate chemical resistance to ethyl alcohol in comparison with the nitrile and latex gloves. In conclusion, glove selection should take movement and polymer type into account. Some glove polymer types are less affected by movement, most notably the latex glove in this test. With nitrile gloves, at least a factor of three should be used when attempting to assign a protection factor when repetitive hand motions are anticipated. Ultimately, the latex gloves outperformed nitrile and vinyl in these tests, which evaluated the effect of movement on chemical permeation. Future research should aim to resolve some of the observed discrepancies in test results with latex and vinyl gloves. PMID:24689368

  11. One-Pot Catalytic Enantio- and Diastereoselective Syntheses of anti-, syn-cis-Disubstituted, and syn-Vinyl Cyclopropyl Alcohols

    PubMed Central

    Kim, Hun Young; Salvi, Luca; Carroll, Patrick J.; Walsh, Patrick J.

    2009-01-01

    Highly enantio- and diastereoselective methods for the synthesis of a variety of cyclopropyl alcohols are reported. These methods represent the first one-pot approaches to syn-vinyl cyclopropyl alcohols, syn-cis-disubstituted cyclopropyl alcohols, and anti-cyclopropyl alcohols from achiral precursors. The methods begin with enantioselective C–C bond formations promoted by a MIB-based zinc catalyst to generate allylic alkoxide intermediates. The intermediates are then subjected to in situ alkoxide-directed cyclopropanation to provide cyclopropyl alcohols. In the synthesis of vinyl cyclopropyl alcohols, hydroboration of enynes is followed by transmetalation of the resulting dienylborane to zinc to provide dienylzinc reagents. Enantioselective addition to aldehydes generates the requisite dienyl zinc alkoxides, which are then subjected to in situ cyclopropanation to furnish vinyl cyclopropyl alcohols. Cyclopropanation occurs at the double bond allylic to the alkoxide. Using this method, syn-vinylcyclopropyl alcohols are obtained in 65–85% yield, 76–93% ee, and >19:1 dr. To prepare anti-cyclopropanols, enantioselective addition of alkylzinc reagents to conjugated enals provides allylic zinc alkoxides. Because direct cyclopropanation provides syn-cyclopropyl alcohols, the intermediate allylic alkoxides were treated with TMSCl/Et3N to generate intermediate silyl ethers. In situ cyclopropanation of the allylic silyl ether resulted in cyclopropanation to form the anti-cyclopropyl silyl ether. Workup with TBAF affords the anti-cyclopropyl alcohols in one-pot in 60–82% yield, 89–99% ee, and ≥10:1 dr. For the synthesis of cis-disubstituted cyclopropyl alcohols, in situ generated (Z)-vinyl zinc reagents were employed in asymmetric addition to aldehydes to generate (Z)-allylic zinc alkoxides. In situ cyclopropanation provides syn-cis-disubstituted cyclopropyl alcohols in 42–70% yield, 88–97% ee, and >19:1 dr. These one-pot procedures enable the synthesis of a

  12. Prolonged Hypocalcemic Effect by Pulmonary Delivery of Calcitonin Loaded Poly(Methyl Vinyl Ether Maleic Acid) Bioadhesive Nanoparticles

    PubMed Central

    Varshosaz, J.; Minaiyan, M.; Forghanian, M.

    2014-01-01

    The purpose of the present study was to design a pulmonary controlled release system of salmon calcitonin (sCT). Therefore, poly(methyl vinyl ether maleic acid) [P(MVEMA)] nanoparticles were prepared by ionic cross-linking method using Fe2+ and Zn2+ ions. Physicochemical properties of nanoparticles were studied in vitro. The stability of sCT in the optimized nanoparticles was studied by electrophoretic gel method. Plasma calcium levels until 48 h were determined in rats as pulmonary-free sCT solution or nanoparticles (25 μg·kg−1), iv solution of sCT (5 μg·kg−1), and pulmonary blank nanoparticles. The drug remained stable during fabrication and tests on nanoparticles. The optimized nanoparticles showed proper physicochemical properties. Normalized reduction of plasma calcium levels was at least 2.76 times higher in pulmonary sCT nanoparticles compared to free solution. The duration of hypocalcemic effect of pulmonary sCT nanoparticles was 24 h, while it was just 1 h for the iv solution. There was not any significant difference between normalized blood calcium levels reduction in pulmonary drug solution and iv injection. Pharmacological activity of nanoparticles after pulmonary delivery was 65% of the iv route. Pulmonary delivery of P(MVEMA) nanoparticles of sCT enhanced and prolonged the hypocalcemic effect of the drug significantly. PMID:24701588

  13. Efficient Synthesis of Molecular Precursors for Para-Hydrogen-Induced Polarization of Ethyl Acetate-1-(13) C and Beyond.

    PubMed

    Shchepin, Roman V; Barskiy, Danila A; Coffey, Aaron M; Manzanera Esteve, Isaac V; Chekmenev, Eduard Y

    2016-05-10

    A scalable and versatile methodology for production of vinylated carboxylic compounds with (13) C isotopic label in C1 position is described. It allowed synthesis of vinyl acetate-1-(13) C, which is a precursor for preparation of (13) C hyperpolarized ethyl acetate-1-(13) C, which provides a convenient vehicle for potential in vivo delivery of hyperpolarized acetate to probe metabolism in living organisms. Kinetics of vinyl acetate molecular hydrogenation and polarization transfer from para-hydrogen to (13) C via magnetic field cycling were investigated. Nascent proton nuclear spin polarization (%PH ) of ca. 3.3 % and carbon-13 polarization (%P13C ) of ca. 1.8 % were achieved in ethyl acetate utilizing 50 % para-hydrogen corresponding to ca. 50 % polarization transfer efficiency. The use of nearly 100% para-hydrogen and the improvements of %PH of para-hydrogen-nascent protons may enable production of (13) C hyperpolarized contrast agents with %P13C of 20-50 % in seconds using this chemistry. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Poly(vinyl methyl ether/maleic anhydride)-Doped PEG-PLA Nanoparticles for Oral Paclitaxel Delivery To Improve Bioadhesive Efficiency.

    PubMed

    Wang, Qian; Li, Chan; Ren, Tianyang; Chen, Shizhu; Ye, Xiaoxia; Guo, Hongbo; He, Haibing; Zhang, Yu; Yin, Tian; Liang, Xing-Jie; Tang, Xing

    2017-10-02

    Bioadhesive nanoparticles based on poly(vinyl methyl ether/maleic anhydride) (PVMMA) and poly(ethylene glycol) methyl ether-b-poly(d,l-lactic acid) (mPEG-b-PLA) were produced by the emulsification solvent evaporation method. Paclitaxel was utilized as the model drug, with an encapsulation efficiency of up to 90.2 ± 4.0%. The nanoparticles were uniform and spherical in shape and exhibited a sustained drug release compared with Taxol. m-NPs also exhibited favorable bioadhesive efficiency at the same time. Coumarin 6 or DiR-loaded nanoparticles with/without PVMMA (C6-m-NPs/DiR-m-NPs or C6-p-NPs/DiR-p-NPs) were used for cellular uptake and intestinal adhesion experiments, respectively. C6-m-NPs were shown to enhance cellular uptake, and caveolae/lipid raft mediated endocytosis was the primary route for the uptake of the nanoparticles. Favorable bioadhesive efficiency led to prolonged retention in the intestine reflected by the fluorescence in isolated intestines ex vivo. In a ligated intestinal loops model, C6-m-NPs showed a clear advantage for transporting NPs across the mucus layer over C6-p-NPs and free C6. The apparent permeability coefficient (Papp) of PTX-m-NPs through Caco-2/HT29 monolayers was 1.3- and 1.6-fold higher than PTX-p-NPs and Taxol, respectively, which was consistent with the AUC 0-t of different PTX formulations after oral administration in rats. PTX-m-NPs also exhibited a more effective anticancer efficacy, with an IC 50 of 0.2 ± 1.4 μg/mL for A549 cell lines, further demonstrating the advantage of bioadhesive nanoparticles. The bioadhesive nanoparticles m-NPs demonstrated both mucus permeation and epithelial absorption, and thus, this bioadhesive drug delivery system has the potential to improve the bioavailability of drugs that are insoluble in the gastrointestinal environment.

  15. Self-healing pH-sensitive poly[(methyl vinyl ether)-alt-(maleic acid)]-based supramolecular hydrogels formed by inclusion complexation between cyclodextrin and adamantane.

    PubMed

    Ma, Xiaoe; Zhou, Naizhen; Zhang, Tianzhu; Hu, Wanjun; Gu, Ning

    2017-04-01

    Self-healing materials are of interest for drug delivery, cell and gene therapy, tissue engineering, and other biomedical applications. In this work, on the base of biocompatible polymer poly(methyl vinyl ether-alt-maleic acid) (P(MVE-alt-MA)), host polymer β-cyclodextrin-grafted P(MVE-alt-MA) (P(MVE-alt-MA)-g-β-CD) and guest polymer adamantane-grafted P(MVE-alt-MA) (P(MVE-alt-MA)-g-Ad) were first prepared. Then through taking advantage of the traditional host-guest interaction of β-cyclodextrin and adamantane, a novel self-healing pH-sensitive physical P(MVE-alt-MA)-g-β-CD/P(MVE-alt-MA)-g-Ad supramolecular hydrogels were obtained after simply mixing the aqueous solution of host polymer and guest polymer. This kind of supramolecular hydrogels not only possess pH-sensitivity, but also possess the ability to repair themselves after being damaged. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. AVOIDING HYDROLYSIS OF FUEL ETHER OXYGENATES DURING STATIC HEADSPACE ANALYSIS

    EPA Science Inventory

    A headspace autosampler, gas chromatograph and ion trap mass spectrometer (headspace GC/MS) were used for trace analysis of fuel oxygenates and related compounds and aromatics in water. A method has been developed for determination of methyl tert-butyl ether (MTBE), ethyl tert-b...

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

    PubMed

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

    2017-06-01

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

  18. A novel biobased plasticizer of epoxidized cardanol glycidylether: Synthesis and application in soft poly(vinyl chloride) films

    USDA-ARS?s Scientific Manuscript database

    A novel plasticizer derived from cardanol, epoxied cardanol glycidyl ether (ECGE), was synthesized and characterized by 1H-NMR and 13C-NMR. Effects of the ECGE combined with dioctyl phthalate (DOP), a commercial plasticizer, in soft poly(vinyl chloride) (PVC) films were studied. Dynamic mechanical a...

  19. Understanding How the Presence of Uniform Electric Fields Can Shift the Miscibility of Polystyrene/Poly(vinyl methyl ether) Blends

    NASA Astrophysics Data System (ADS)

    Kriisa, Annika; Roth, Connie B.

    2015-03-01

    Techniques which can externally control and manipulate the phase behavior of polymeric systems, without altering chemistry on a molecular level, have great practical benefits. One such possible mechanism is the use of electric fields, shown to cause interfacial instabilities, orientation of morphologies, and phase transitions in polymer blends and block copolymers. We have recently demonstrated that the presence of uniform electric fields can also strongly enhance the miscibility of polystyrene (PS) / poly(vinyl methyl ether) (PVME) blends [J. Chem. Phys. 2014, 141, 134908]. Using fluorescence to measure the phase separation temperature Ts of PS/PVME blends with and without electric fields, we show that Ts can be reproducibly and reversibly increased by 13.5 +/- 1.4 K for electric fields of 17 kV/mm for this lower critical solution temperature (LCST) blend. This increase in blend miscibility with electric fields represents some of the largest absolute shifts in Ts ever recorded, well outside of experimental error. The best theoretical prediction for the expected shift in Ts with electric field for this system is still two orders of magnitude smaller than that observed experimentally. We discuss the limitations of this theoretical prediction and consider possible factors affecting miscibility that may need to be also included.

  20. On the Formation of the C2H6O Isomers Ethanol (C2H5OH) and Dimethyl Ether (CH3OCH3) in Star-forming Regions

    NASA Astrophysics Data System (ADS)

    Bergantini, Alexandre; Maksyutenko, Pavlo; Kaiser, Ralf I.

    2017-06-01

    The structural isomers ethanol (CH3CH2OH) and dimethyl ether (CH3OCH3) were detected in several low-, intermediate-, and high-mass star-forming regions, including Sgr B2, Orion, and W33A, with the relative abundance ratios of ethanol/dimethyl ether varying from about 0.03 to 3.4. Until now, no experimental data regarding the formation mechanisms and branching ratios of these two species in laboratory simulation experiments could be provided. Here, we exploit tunable photoionization reflectron time-of-flight mass spectrometry (PI-ReTOF-MS) to detect and analyze the production of complex organic molecules (COMs) resulting from the exposure of water/methane (H2O/CH4) ices to energetic electrons. The main goal is to understand the formation mechanisms in star-forming regions of two C2H6O isomers: ethanol (CH3CH2OH) and dimethyl ether (CH3OCH3). The results show that the experimental branching ratios favor the synthesis of ethanol versus dimethyl ether (31 ± 11:1). This finding diverges from the abundances observed toward most star-forming regions, suggesting that production routes on interstellar grains to form dimethyl ether might be missing; alternatively, ethanol can be overproduced in the present simulation experiments, such as via radical-radical recombination pathways involving ethyl and hydroxyl radicals. Finally, the PI-ReTOF-MS data suggest the formation of methylacetylene (C3H4), ketene (CH2CO), propene (C3H6), vinyl alcohol (CH2CHOH), acetaldehyde (CH3CHO), and methyl hydroperoxide (CH3OOH), in addition to ethane (C2H6), methanol (CH3OH), and CO2 detected from infrared spectroscopy. The yield of all the confirmed species is also determined.

  1. Rare 2-Substituted Purine Nucleosides

    DTIC Science & Technology

    1989-05-01

    of 10 with the tributyltin enolate of acetone gave 24 in good yields. Compound 24 can be easily deprotected to 1 with tetrabutylammonium fluoride. It...was achieved through the use of ethyl vinyltributyltin ether. This organostannane was prepared by the radical coupling of tributyltin hydride with...from the reaction of the 2-iodo compound 19 with vinyl- tributyltin under palladium catalysis, followed by deprotection with trimethylsilyl iodide

  2. 21 CFR 177.1360 - Ethylene-vinyl acetate-vinyl alcohol copolymers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene-vinyl acetate-vinyl alcohol copolymers... for Use as Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1360 Ethylene-vinyl acetate-vinyl alcohol copolymers. Ethylene-vinyl acetate-vinyl alcohol copolymers (CAS Reg. No. 26221-27-2...

  3. Ether modifications to 1-[2-(3,4-dimethoxyphenyl)ethyl]-4-(3-phenylpropyl)piperazine (SA4503): effects on binding affinity and selectivity for sigma receptors and monoamine transporters.

    PubMed

    Xu, Rong; Lord, Sarah A; Peterson, Ryan M; Fergason-Cantrell, Emily A; Lever, John R; Lever, Susan Z

    2015-01-01

    Two series of novel ether analogs of the sigma (σ) receptor ligand 1-[2-(3,4-dimethoxyphenyl)ethyl]-4-(3-phenylpropyl)piperazine (SA4503) have been prepared. In one series, the alkyl portion of the 4-methoxy group was replaced with allyl, propyl, bromoethyl, benzyl, phenethyl, and phenylpropyl moieties. In the second series, the 3,4-dimethoxy was replaced with cyclic methylenedioxy, ethylenedioxy and propylenedioxy groups. These ligands, along with 4-O-des-methyl SA4503, were evaluated for σ1 and σ2 receptor affinity, and compared to SA4503 and several known ether analogs. SA4503 and a subset of ether analogs were also evaluated for dopamine transporter (DAT) and serotonin transporter (SERT) affinity. The highest σ1 receptor affinities, Ki values of 1.75-4.63 nM, were observed for 4-O-des-methyl SA4503, SA4503 and the methylenedioxy analog. As steric bulk increased, σ1 receptor affinity decreased, but only to a point. Allyl, propyl and bromoethyl substitutions gave σ1 receptor Ki values in the 20-30 nM range, while bulkier analogs having phenylalkyl, and Z- and E-iodoallyl, ether substitutions showed higher σ1 affinities, with Ki values in the 13-21 nM range. Most ligands studied exhibited comparable σ1 and σ2 affinities, resulting in little to no subtype selectivity. SA4503, the fluoroethyl analog and the methylenedioxy congener showed modest six- to fourteen-fold selectivity for σ1 sites. DAT and SERT interactions proved much more sensitive than σ receptor interactions to these structural modifications. For example, the benzyl congener (σ1Ki=20.8 nM; σ2Ki=16.4 nM) showed over 100-fold higher DAT affinity (Ki=121 nM) and 6-fold higher SERT affinity (Ki=128nM) than the parent SA4503 (DAT Ki=12650 nM; SERT Ki=760 nM). Thus, ether modifications to the SA4503 scaffold can provide polyfunctional ligands having a broader spectrum of possible pharmacological actions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Aluminum–phthalocyanine chloride associated to poly(methyl vinyl ether-co-maleic anhydride) nanoparticles as a new third-generation photosensitizer for anticancer photodynamic therapy

    PubMed Central

    Muehlmann, Luis Alexandre; Ma, Beatriz Chiyin; Longo, João Paulo Figueiró; Almeida Santos, Maria de Fátima Menezes; Azevedo, Ricardo Bentes

    2014-01-01

    Photodynamic therapy is generally considered to be safer than conventional anticancer therapies, and it is effective against different kinds of cancer. However, its clinical application has been significantly limited by the hydrophobicity of photosensitizers. In this work, a system composed of the hydrophobic photosensitizer aluminum–phthalocyanine chloride (AlPc) associated with water dispersible poly(methyl vinyl ether-co-maleic anhydride) nanoparticles is described. AlPc was associated with nanoparticles produced by a method of solvent displacement. This system was analyzed for its physicochemical characteristics, and for its photodynamic activity in vitro in cancerous (murine mammary carcinoma cell lineage 4T1, and human mammary adenocarcinoma cells MCF-7) and noncancerous (murine fibroblast cell lineage NIH/3T3, and human mammary epithelial cell lineage MCF-10A) cell lines. Cell viability and the elicited mechanisms of cell death were evaluated after the application of photodynamic therapy. This system showed improved photophysical and photochemical properties in aqueous media in comparison to the free photosensitizer, and it was effective against cancerous cells in vitro. PMID:24634582

  5. Dual-mesoporous ZSM-5 zeolite with highly b-axis-oriented large mesopore channels for the production of benzoin ethyl ether.

    PubMed

    Zhou, Xiaoxia; Chen, Hangrong; Zhu, Yan; Song, Yudian; Chen, Yu; Wang, Yongxia; Gong, Yun; Zhang, Guobin; Shu, Zhu; Cui, Xiangzhi; Zhao, Jinjin; Shi, Jianlin

    2013-07-22

    Dual-mesoporous ZSM-5 zeolite with highly b axis oriented large mesopores was synthesized by using nonionic copolymer F127 and cationic surfactant CTAB as co-templates. The product contains two types of mesopores--smaller wormlike ones of 3.3 nm in size and highly oriented larger ones of 30-50 nm in diameter along the b axis--and both of them interpenetrate throughout the zeolite crystals and interconnect with zeolite microporosity. The dual-mesoporous zeolite exhibits excellent catalytic performance in the condensation of benzaldehyde with ethanol and greater than 99 % selectivity for benzoin ethyl ether at room temperature, which can be ascribed to the zeolite lattice structure offering catalytically active sites and the hierarchical and oriented mesoporous structure providing fast access of reactants to these sites in the catalytic reaction. The excellent recyclability and high catalytic stability of the catalyst suggest prospective applications of such unique mesoporous zeolites in the chemical industry. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Reactions of VX, HD, and their simulants with NaY and AgY zeolites. Desulfurization of VX on AgY

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wagner, G.W.; Bartram, P.W.

    1999-11-09

    The room-temperature reactions of the chemical warfare agents VX (O-ethyl S-2-(diisopropylamino)-ethyl methylphosphonothioate), HD (2,2{prime}-dichloroethyl sulfide, or mustard), and their common simulants, O,S-diethyl phenylphosphonothioate (DEPPT) and 2-chloroethyl phenyl sulfide (CEPS), with NaY and silver-exchanged (AgY) zeolites have been studied using solid-state magic angle spinning NMR. VX hydrolyzes via exclusive cleavage of the P{single{underscore}bond}S bond on both NaY and AgY to yield ethyl methylphosphonate (EMPA). The reaction is significantly faster on AgY than on NaY, suggesting catalysis by silver. On AgY, an intermediate silver salt of EMPA is apparently formed which is slowly converted to ethyl 2-(diisopropylamino)ethyl methylphosphonate (QB, the desulfurized analoguemore » of VX) in about a 78% yield. DEPPT similarly hydrolyzes via P{single{underscore}bond}S cleavage on AgY to yield an apparent silver salt of ethyl phenylphosphonate, which does not undergo further reaction to the desulfurized analogue. No reaction is observed for DEPPT on NaY. HD on AgY forms both vinyl sulfide and the cyclic ether 1,4-thioxane. HD reacts faster on NaY to exclusively form the CH-TG sulfonium ion (HOCH{sub 2}CH{sub 2}SCH{sub 2}CH{sub 2}S{sup +}[CH{sub 2}CH{sub 2}OH]{sub 2}). CEPS also reacts faster on NaY, forming 2-hydroxyethyl phenyl sulfide. On AgY, CEPS does not give the vinyl product, but does yield the ether product PhSCH{sub 2}CH{sub 2}OCH{sub 2}CH{sub 2}SPh. A mechanism is proposed for the silver-catalyzed hydrolysis of VX, the desulfurization of the cleaved thiol, and the formation of QB.« less

  7. Preparation of Poly-(Methyl vinyl ether-co-maleic Anhydride) Nanoparticles by Solution-Enhanced Dispersion by Supercritical CO2

    PubMed Central

    Chen, Ai-Zheng; Wang, Guang-Ya; Wang, Shi-Bin; Feng, Jian-Gang; Liu, Yuan-Gang; Kang, Yong-Qiang

    2012-01-01

    The supercritical CO2-based technologies have been widely used in the formation of drug and/or polymer particles for biomedical applications. In this study, nanoparticles of poly-(methyl vinyl ether-co-maleic anhydride) (PVM/MA) were successfully fabricated by a process of solution-enhanced dispersion by supercritical CO2 (SEDS). A 23 factorial experiment was designed to investigate and identify the significance of the processing parameters (concentration, flow and solvent/nonsolvent) for the surface morphology, particle size, and particle size distribution of the products. The effect of the concentration of PVM/MA was found to be dominant in the results regarding particle size. Decreasing the initial solution concentration of PVM/MA decreased the particle size significantly. After optimization, the resulting PVM/MA nanoparticles exhibited a good spherical shape, a smooth surface, and a narrow particle size distribution. Fourier transform infrared spectroscopy (FTIR) spectra demonstrated that the chemical composition of PVM/MA was not altered during the SEDS process and that the SEDS process was therefore a typical physical process. The absolute value of zeta potential of the obtained PVM/MA nanoparticles was larger than 40 mV, indicating the samples’ stability in aqueous suspension. Analysis of thermogravimetry-differential scanning calorimetry (TG-DSC) revealed that the effect of the SEDS process on the thermostability of PVM/MA was negligible. The results of gas chromatography (GC) analysis confirmed that the SEDS process could efficiently remove the organic residue.

  8. Antibacterial [2-(Methacryloyloxy) ethyl] Trimethylammonium Chloride Functionalized Reduced Graphene Oxide/Poly(ethylene-co-vinyl alcohol) Multilayer Barrier Film for Food Packaging.

    PubMed

    Wang, Hualin; Chen, Minmin; Jin, Chongyang; Niu, Baicheng; Jiang, Suwei; Li, Xingjiang; Jiang, Shaotong

    2018-01-24

    The objective of present work was to construct antibacterial [2-(methacryloyloxy) ethyl] trimethylammonium chloride functionalized reduced graphene oxide/poly(ethylene-co-vinyl alcohol) (MTAC-rGO/EVOH) multilayer barrier films by using layer-by-layer assembly under a parallel electric field. Besides barrier and mechanical properties, the antibacterial activities of the film and cytotoxicity of MTAC-rGO nanosheets were extensively investigated. The functionalization of rGO was achieved by grafting MTAC onto a graphene framework through C (sp 3 )-C bonds. The assembly of MTAC-rGO on the EVOH matrix not only significantly improved film mechanical strength, but also endowed the targeting film with outstanding moisture barrier even under a relative humidity of 99% (e.g., 0.019 g m -2 s -1 atm -1 for (MTAC-rGO/EVOH) 20 ) besides good oxygen barrier (e.g., 0.07 cm 3 m -2 d -1 atm -1 for (MTAC-rGO/EVOH) 20 ). Among the testing films, MTAC-rGO/EVOH film had the best antibacterial activity, and the activity against S. aureus was better than E. coli. Meanwhile, the cytotoxicity of MTAC-rGO nanosheets was very low. Results suggest that MTAC-rGO/EVOH film may have great potential in food active packaging.

  9. Sister chromatid exchanges induced by inhaled anesthetics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    White,A.E.; Takehisa, S.; Eger II, E.I.

    1970-05-01

    There is sufficient evidence that anesthetics may cause cancer to justify a test of their carcinogenic potential. Baden et al., using the Ames test, a rapid and inexpensive genetic indicator of carcinogenicity, have shown that among currently used anesthetics fluorxene alone caused bacterial mutations. The authors used the sister chromatid exchange (SCE) technique, another rapid assay of mutagenic-carcinogenic potential. The frequency of sister chromatid exchanges in Chinese hamster ovary cells increases when the cell cultures are exposed to mutagen-carcinogens, particulary in the presence of a metabolic activating system. With this test system a one-hour exposure to 1 MAC nitrous oxide,more » diethyl ether, trichloroethylene, halothane, enflurane, isoflurane, methoxyflurane, or chloroform did not increase SCE values. Divinyl ether, fluroxene and ethyl vinyl ether increased SCE values in the same circumstances. Results of this study of mammalian cells suggest that no currently used anesthetic is a mutagen-carcinogen. The results also suggest that anesthetics containing a vinyl moiety may be mutagen-carcinogens.« less

  10. 40 CFR 721.10401 - Oxirane, 2-ethyl-, polymer with oxirane, mono-C11-15-sec-alkyl ethers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Oxirane, 2-ethyl-, polymer with... Significant New Uses for Specific Chemical Substances § 721.10401 Oxirane, 2-ethyl-, polymer with oxirane...) The chemical substance identified as oxirane, 2-ethyl-, polymer with oxirane, mono C11-15-sec-alkyl...

  11. 40 CFR 721.10400 - Oxirane, 2-ethyl-, polymer with oxirane, mono-C12-14-sec-alkyl ethers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Oxirane, 2-ethyl-, polymer with... Significant New Uses for Specific Chemical Substances § 721.10400 Oxirane, 2-ethyl-, polymer with oxirane...) The chemical substance identified as oxirane, 2-ethyl-, polymer with oxirane, mono-C12-14-sec-alkyl...

  12. Proton-Ionizable Crown Ethers. A Short Review

    DTIC Science & Technology

    1989-05-30

    acid methyl ester using sodium hydride as the base in tetrahydrofuran. The m3thyl ester group was hydrolyzed to the carboxylic acid as shown in Procedure...prepared via the appropriate hydroxydibenzo-crown ether and allyl bromide RýIý R2 or ethyl acrylate as shown in Procedure N. 5 2 . 5 6 Disulfonic acid ...similar to Procedure p. 7 4 Once the precursor binrephtho-crown was obtained, it was coupled with bromoacetic acid methyl ester and R, , - R

  13. Selol nanocapsules with a poly(methyl vinyl ether-co-maleic anhydride) shell conjugated to doxorubicin for combinatorial chemotherapy against murine breast adenocarcinoma in vivo.

    PubMed

    Ganassin, Rayane; Horst, Frederico Hillesheim; Camargo, Nichollas Serafim; Chaves, Sacha Braun; Morais, Paulo César; Mosiniewicz-Szablewska, Ewa; Suchocki, Piotr; Figueiró Longo, João Paulo; Azevedo, Ricardo Bentes; Muehlmann, Luis Alexandre

    2018-05-29

    Nanocapsules containing selol and doxorubicin (NCS-DOX) with an oily core of selol and a shell of poly(methyl vinyl ether-co-maleic anhydride) covalently conjugated to doxorubicin were developed in a previous work. In this study, these nanocapsules showed a similar antitumour effect in comparison to the free doxorubicin (DOX) treatment, but showed no evident DOX-related cardiotoxicity, as evidenced by serum creatine kinase-MB (CK-MB) activity. The histopathological analysis showed that the free DOX treatment induced more intense morphological damage to myocardial tissues in comparison to NCS-DOX treatment. Animals treated with free DOX presented important muscle fibre degradation and animals treated with NCS-DOX, heart tissue did not present signals of muscle fibre degeneration. These results indicate that the cardiotoxicity related to DOX is reduced when this drug is carried by the NCS-DOX. Noteworthy, biodistribution analyses showed that NCS-DOX accumulated more intensely in tumours than the free DOX. Thus, this study reinforces the importance of the development of nanocapsules as drug carriers for the treatment of cancer.

  14. 46 CFR 151.50-34 - Vinyl chloride (vinyl chloride monomer).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Vinyl chloride (vinyl chloride monomer). 151.50-34... chloride (vinyl chloride monomer). (a) Copper, aluminum, magnesium, mercury, silver, and their alloys shall... equipment that may come in contact with vinyl chloride liquid or vapor. (b) Valves, flanges, and pipe...

  15. Inhibition of IgE-induced mast cell activation by ethyl tertiary-butyl ether, a bioethanol-derived fuel oxygenate.

    PubMed

    Yamaki, Kouya; Yoshino, Shin

    2009-09-01

    The effect of ethyl tertiary-butyl ether (ETBE), which is widely used as a fuel oxygenate commonly produced from bioethanol, on immunoglobulin (Ig)E-dependent mast cell activation was investigated. The rat mast cell line RBL2H3 sensitised with monoclonal anti-ovalbumin IgE was challenged with ovalbumin in the presence or absence of ETBE, tert-butanol (TBA), which is the main metabolite of ETBE in humans, and ethanol. Degranulation of RBL2H3 was examined by the release of beta-hexosaminidase. To understand the mechanisms responsible for regulating mast cell function, the effects of ETBE, TBA and ethanol on the levels of intracellular calcium, phosphorylation of Akt (as a marker of phosphatidylinositol 3-kinase) and global tyrosine phosphorylation were also measured as indicators of mast cell activation. In the presence of ETBE, TBA or ethanol, IgE-induced release of beta-hexosaminidase was decreased. These compounds also attenuated the IgE-mediated increase in the levels of intracellular Ca(2+), phosphorylation of Akt and global tyrosine phosphorylation in RBL2H3 cells. ETBE, TBA and ethanol inhibited mast cell degranulation by inhibiting the increase in intracellular calcium ion concentration and activation of phosphatidylinositol 3-kinase and protein tyrosine kinase activation, suggesting that exposure to ETBE might affect immune responses, particularly in allergic diseases.

  16. Synthesis of nucleosides and oligonucleotides containing adducts of acrolein and vinyl chloride.

    PubMed

    Nechev, L V; Harris, C M; Harris, T M

    2000-05-01

    Vinyl chloride and acrolein are important industrial chemicals. Both form DNA adducts, vinyl chloride after enzymatic oxidation to chlorooxirane and acrolein by direct reaction. Reaction at the N(2) position of guanine is a major pathway. The resulting 2-oxoethyl and 3-oxopropyl adducts cyclize spontaneously to hydroxyethano and hydroxypropano derivatives, respectively. The two cyclic adducts have been detected in DNA exposed to these mutagens. A new method has been developed for the synthesis of deoxyguanosine adducts of chlorooxirane and acrolein, as well as oligonucleotides containing these adducts. Reaction of O(6)-[(trimethylsilyl)ethyl]-2-fluoro-2'-deoxyinosine with the appropriate aminodiol followed by oxidative cleavage of the diol with NaIO(4) gave the adducts in excellent yields. Reaction of oligonucleotides containing the halonucleoside with the aminodiols followed by NaIO(4) efficiently created the nucleosides in the oligonucleotides. Deoxyadenosine adducts were created similarly using 6-chloropurine 9-(2'-deoxyriboside).

  17. Synthesis of two and antibacterial activity of one novel oxime ether derivatives of erythromycin A.

    PubMed

    Dondas, H A; Yaktubay, N

    2003-10-01

    The synthesis of novel erythromycin A 9-O-(2-ethenesulfony-ethyl)-oxime and erythromycin A 9-O-(3-oxo-butyl)-oxime from erythromycin A (EA) by the Michael reaction is described and to describe the effects of transformation of ketone in position 9 of EA to an oxime ether. This transformation occurred in a single step without protecting of any functional moiety of erythromycin oxime and zero waste manner in good yield. The antibacterial screen of EA 9-O-(2-ethenesulfony-ethyl)-oxime is also reported.

  18. Preparation and characterization of mucoadhesive nanoparticles of poly (methyl vinyl ether-co-maleic anhydride) containing glycyrrhizic acid intended for vaginal administration.

    PubMed

    Aguilar-Rosas, Irene; Alcalá-Alcalá, Sergio; Llera-Rojas, Viridiana; Ganem-Rondero, Adriana

    2015-01-01

    Traditional vaginal preparations reside in the vaginal cavity for relatively a short period of time, requiring multiple doses in order to attain the desired therapeutic effect. Therefore, mucoadhesive systems appear to be appropriate to prolong the residence time in the vaginal cavity. In the current study, mucoadhesive nanoparticles based on poly(methyl vinyl ether-co-maleic anhydride) (PVM/MA) intended for vaginal delivery of glycyrrhizic acid (GA) (a drug with well-known antiviral properties) were prepared and characterized. Nanoparticles were generated by a solvent displacement method. Incorporation of GA was performed during nanoprecipitation, followed by adsorption of drug once nanoparticles were formed. The prepared nanoparticles were characterized in terms of size, Z-potential, morphology, drug loading, interaction of GA with PVM/MA (by differential scanning calorimetry) and the in vitro interaction of nanoparticles with pig mucin (at two pH values, 3.6 and 5; with and without GA adsorbed). The preparation method led to nanoparticles of a mean diameter of 198.5 ± 24.3 nm, zeta potential of -44.8 ± 2.8 mV and drug loading of 15.07 ± 0.86 µg/mg polymer. The highest mucin interaction resulted at pH 3.6 for nanoparticles without GA adsorbed. The data obtained suggest the promise of using mucoadhesive nanoparticles of PVM/MA for intravaginal delivery of GA.

  19. [Complex application 2-ethyl-6-methyl-3-hydroxypyridine-succinate and vinpocetine in cerebrovascular disorder.

    PubMed

    Solovyeva, E Yu; Karneev, A N; Chekanov, A V; Baranova, O A; Choi, I V

    Developing brain ischemia due to cerebral vascularization leads to disruption of brain metabolism. Chronic cerebral hypoperfusion leads to irreversible brain damage and plays an important role in the development of some types of dementia. Early use of antioxidants such as ethyl ether apovincamine acid (vinpocetine) and 2-ethyl-6-methyl-3-hydroxypyridine-succinate in the treatment of this pathology is seen as a real pathogenetically based method of correction of cerebral metabolism with cerebral vascular disorders, demonstrating the increase in cerebral blood flow and also neuroprotective effects. Clinical studies and studies on biological models show that the main mechanisms of action of vinpocetine and 2-ethyl-6-methyl-3-hydroxypyridine-succinate, although have a similar focus, but implementing neuroprotective and nootropic effects via various links in the pathogenesis of ischemic brain damage.

  20. Synthesis and biological evaluation of arctigenin ester and ether derivatives as activators of AMPK.

    PubMed

    Shen, Sida; Zhuang, Jingjing; Chen, Yijia; Lei, Min; Chen, Jing; Shen, Xu; Hu, Lihong

    2013-07-01

    A series of new arctigenin and 9-deoxy-arctigenin derivatives bearing different ester and ether side chains at the phenolic hydroxyl positions are designed, synthesized, and evaluated for activating AMPK potency in L6 myoblasts. Initial biological evaluation indicates that some alkyl ester and phenethyl ether arctigenin derivatives display potential activities in AMPK phosphorylation improvement. Further structure-activity relationship analysis shows that arctigenin ester derivatives 3a, 3h and 9-deoxy-arctigenin phenethyl ether derivatives 6a, 6c, 6d activate AMPK more potently than arctigenin. Moreover, the 2-(3,4-dimethoxyphenyl)ethyl ether moiety of 6c has been demonstrated as a potential functional group to improve the effect of AMPK phosphorylation. The structural optimization of arctigenin leads to the identification of 6c as a promising lead compound that exhibits excellent activity in AMPK activation. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. Emission Studies in CI Engine using LPG and Palm Kernel Methyl Ester as Fuels and Di-ethyl Ether as an Additive

    NASA Astrophysics Data System (ADS)

    Dora, Nagaraju; Jothi, T. J. Sarvoththama

    2018-05-01

    The present study investigates the effectiveness of using di-ethyl ether (DEE) as the fuel additive in engine performance and emissions. Experiments are carried out in a single cylinder four stroke diesel engine at constant speed. Two different fuels namely liquefied petroleum gas (LPG) and palm kernel methyl ester (PKME) are used as primary fuels with DEE as the fuel additive. LPG flow rates of 0.6 and 0.8 kg/h are considered, and flow rate of DEE is varied to maintain the constant engine speed. In case of PKME fuel, it is blended with diesel in the latter to the former ratio of 80:20, and DEE is varied in the volumetric proportion of 1 and 2%. Results indicate that for the engine operating in LPG-DEE mode at 0.6 kg/h of LPG, the brake thermal efficiency is lowered by 26%; however, NOx is subsequently reduced by around 30% compared to the engine running with only diesel fuel at 70% load. Similarly, results of PKME blended fuel showed a drastic reduction in the NOx and CO emissions. In these two modes of operation, DEE is observed to be significant fuel additive regarding emissions reduction.

  2. Poly(1-Vinyl-1,2,4-triazolium) Poly(Ionic Liquid)s: Synthesis and the Unique Behavior in Loading Metal Ions.

    PubMed

    Zhang, Weiyi; Yuan, Jiayin

    2016-07-01

    Herein, the synthesis of a series of poly(4-alkyl-1-vinyl-1,2,4-triazolium) poly(ionic liquid)s is reported either via straightforward free radical polymerization of their corresponding ionic liquid monomers or via anion metathesis of the polymer precursors bearing halide as counter anion. The ionic liquid monomers are first prepared via N-alkylation reaction of commercially available 1-vinyl-1,2,4-triazole with alkyl iodides, followed by anion metathesis with targeted fluorinated anions. The thermal properties and solubilities of these poly(ionic liquid)s have been systematically investigated. Interestingly, it is found that the poly(4-ethyl-1-vinyl-1,2,4-triazolium) poly(ionic liquid) exhibited an improved loading capacity of transition metal ions in comparison with its imidazolium counterpart. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. 46 CFR 151.50-34 - Vinyl chloride (vinyl chloride monomer).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Vinyl chloride (vinyl chloride monomer). 151.50-34 Section 151.50-34 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS... chloride (vinyl chloride monomer). (a) Copper, aluminum, magnesium, mercury, silver, and their alloys shall...

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

    PubMed

    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.

  5. Gas-phase infrared spectra of vinyl selenol and vinyl tellurol.

    PubMed

    Benidar, Abdessamad; Khater, Brahim; Guillemin, Jean-Claude; Gámez, José A; Yáñez, Manuel

    2009-11-19

    The infrared spectra (3500-500 cm(-1)) of gaseous vinyl selenol and vinyl tellurol have been recorded at 0.1 cm(-1) resolution. For the latter the spectra were obtained at room temperature, but for the former a temperature of -40 degrees C was required because of the chemical instability of vinyl selenol at room temperature. To compensate the very weak vapor pressure of vinyl tellurol at room temperature, a long optical path up to 136 m was necessary to record its spectrum. B3LYP density functional theory (DFT) calculations have been performed to assign the different absorption bands. Since an unambiguous assignment of the absorption bands requires a precise knowledge on the relative abundance of the syn and gauche rotamers of these compounds, their relative energies and their anharmonic vibrational frequencies were obtained using a very extended Def2-QZVP basis set. Two rotamers, the syn, which is planar, and a nonplanar gauche, were found to be local minima for both compounds. The gauche rotamer presents two degenerate conformers, which differ by the position of the SeH (TeH) hydrogen atom above or below the molecular plane. Our theoretical results are in good agreement with the main features of the experimental spectra. Fundamental bands and some combination bands of vinyl selenol and vinyl tellurol were assigned and compared with those of vinyl alcohol and vinyl thiol, whose spectra had been reported previously in the literature.

  6. Gas-Phase Infrared Spectra of Vinyl Selenol and Vinyl Tellurol

    NASA Astrophysics Data System (ADS)

    Benidar, Abdessamad; Khater, Brahim; Guillemin, Jean-Claude; Gámez, José A.; Yáñez, Manuel

    2009-10-01

    The infrared spectra (3500-500 cm-1) of gaseous vinyl selenol and vinyl tellurol have been recorded at 0.1 cm-1 resolution. For the latter the spectra were obtained at room temperature, but for the former a temperature of -40 °C was required because of the chemical instability of vinyl selenol at room temperature. To compensate the very weak vapor pressure of vinyl tellurol at room temperature, a long optical path up to 136 m was necessary to record its spectrum. B3LYP density functional theory (DFT) calculations have been performed to assign the different absorption bands. Since an unambiguous assignment of the absorption bands requires a precise knowledge on the relative abundance of the syn and gauche rotamers of these compounds, their relative energies and their anharmonic vibrational frequencies were obtained using a very extended Def2-QZVP basis set. Two rotamers, the syn, which is planar, and a nonplanar gauche, were found to be local minima for both compounds. The gauche rotamer presents two degenerate conformers, which differ by the position of the SeH (TeH) hydrogen atom above or below the molecular plane. Our theoretical results are in good agreement with the main features of the experimental spectra. Fundamental bands and some combination bands of vinyl selenol and vinyl tellurol were assigned and compared with those of vinyl alcohol and vinyl thiol, whose spectra had been reported previously in the literature.

  7. Pre-dispersed organo-montmorillonite (organo-MMT) nanofiller: Morphology, cytocompatibility and impact on flexibility, toughness and biostability of biomedical ethyl vinyl acetate (EVA) copolymer.

    PubMed

    Osman, Azlin F; M Fitri, Tuty Fareyhynn; Rakibuddin, Md; Hashim, Fatimah; Tuan Johari, Syed Ahmad Tajudin; Ananthakrishnan, Rajakumar; Ramli, Rafiza

    2017-05-01

    Polymer-clay based nanocomposites are among the attractive materials to be applied for various applications, including biomedical. The incorporation of the nano sized clay (nanoclay) into polymer matrices can result in their remarkable improvement in mechanical, thermal and barrier properties as long as the nanofillers are well exfoliated and dispersed throughout the matrix. In this work, exfoliation strategy through pre-dispersing process of the organically modified montmorillonite (organo-MMT) nanofiller was done to obtain ethyl vinyl acetate (EVA) nanocomposite with improved flexibility, toughness, thermal stability and biostability. Our results indicated that the degree of organo-MMT exfoliation affects its cytotoxicity level and the properties of the resulting EVA nanocomposite. The pre-dispersed organo-MMT by ultrasonication in water possesses higher degree of exfoliation as compared to its origin condition and significantly performed reduced cytotoxicity level. Beneficially, this nanofiller also enhanced the EVA flexibility, thermal stability and biostability upon the in vitro exposure. We postulated that these were due to plasticizing effect and enhanced EVA-nanofiller interactions contributing to more stable chemical bonds in the main copolymer chains. Improvement in copolymer flexibility is beneficial for close contact with human soft tissue, while enhancement in toughness and biostability is crucial to extend its life expectancy as insulation material for implantable device. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. On the Formation of the C{sub 2}H{sub 6}O Isomers Ethanol (C{sub 2}H{sub 5}OH) and Dimethyl Ether (CH{sub 3}OCH{sub 3}) in Star-forming Regions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bergantini, Alexandre; Maksyutenko, Pavlo; Kaiser, Ralf I., E-mail: ralfk@hawaii.edu

    The structural isomers ethanol (CH{sub 3}CH{sub 2}OH) and dimethyl ether (CH{sub 3}OCH{sub 3}) were detected in several low-, intermediate-, and high-mass star-forming regions, including Sgr B2, Orion, and W33A, with the relative abundance ratios of ethanol/dimethyl ether varying from about 0.03 to 3.4. Until now, no experimental data regarding the formation mechanisms and branching ratios of these two species in laboratory simulation experiments could be provided. Here, we exploit tunable photoionization reflectron time-of-flight mass spectrometry (PI-ReTOF-MS) to detect and analyze the production of complex organic molecules (COMs) resulting from the exposure of water/methane (H{sub 2}O/CH{sub 4}) ices to energetic electrons.more » The main goal is to understand the formation mechanisms in star-forming regions of two C{sub 2}H{sub 6}O isomers: ethanol (CH{sub 3}CH{sub 2}OH) and dimethyl ether (CH{sub 3}OCH{sub 3}). The results show that the experimental branching ratios favor the synthesis of ethanol versus dimethyl ether (31 ± 11:1). This finding diverges from the abundances observed toward most star-forming regions, suggesting that production routes on interstellar grains to form dimethyl ether might be missing; alternatively, ethanol can be overproduced in the present simulation experiments, such as via radical–radical recombination pathways involving ethyl and hydroxyl radicals. Finally, the PI-ReTOF-MS data suggest the formation of methylacetylene (C{sub 3}H{sub 4}), ketene (CH{sub 2}CO), propene (C{sub 3}H{sub 6}), vinyl alcohol (CH{sub 2}CHOH), acetaldehyde (CH{sub 3}CHO), and methyl hydroperoxide (CH{sub 3}OOH), in addition to ethane (C{sub 2}H{sub 6}), methanol (CH{sub 3}OH), and CO{sub 2} detected from infrared spectroscopy. The yield of all the confirmed species is also determined.« less

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

    PubMed

    Bombach, Petra; Nägele, Norbert; Rosell, Mònica; Richnow, Hans H; Fischer, Anko

    2015-04-09

    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 [(13)C6]-ETBE (BACTRAP(®)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 (13)C-incorporation into microbial total lipid fatty acids extracted from the in situ microcosms was found, providing clear evidence of ETBE biodegradation. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Vinyl Chloride

    Cancer.gov

    Learn about vinyl chloride, which can raise the risk of a rare form of liver cancer, as well as brain and lung cancers, and leukemia and lymphoma. Vinyl chloride is used primarily to make PVC, a substance used in products such as pipes.

  11. Unexpected behavior of ultra-thin films of blends of polystyrene/poly(vinyl methyl ether) studied by specific heat spectroscopy

    NASA Astrophysics Data System (ADS)

    Madkour, Sherif; Szymoniak, Paulina; Schick, Christoph; Schönhals, Andreas

    2017-05-01

    Specific heat spectroscopy (SHS) employing AC nanochip calorimetry was used to investigate the glassy dynamics of ultra-thin films (thicknesses: 10 nm-340 nm) of a polymer blend, which is miscible in the bulk. In detail, a Poly(vinyl methyl ether) (PVME)/Polystyrene (PS) blend with the composition of 25/75 wt. % was studied. The film thickness was controlled by ellipsometry while the film topography was checked by atomic force microscopy. The results are discussed in the framework of the balance between an adsorbed and a free surface layer on the glassy dynamics. By a self-assembling process, a layer with a reduced mobility is irreversibly adsorbed at the polymer/substrate interface. This layer is discussed employing two different scenarios. In the first approach, it is assumed that a PS-rich layer is adsorbed at the substrate. Whereas in the second approach, a PVME-rich layer is suggested to be formed at the SiO2 substrate. Further, due to the lower surface tension of PVME, with respect to air, a nanometer thick PVME-rich surface layer, with higher molecular mobility, is formed at the polymer/air interface. By measuring the glassy dynamics of the thin films of PVME/PS in dependence on the film thickness, it was shown that down to 30 nm thicknesses, the dynamic Tg of the whole film was strongly influenced by the adsorbed layer yielding a systematic increase in the dynamic Tg with decreasing the film thickness. However, at a thickness of ca. 30 nm, the influence of the mobile surface layer becomes more pronounced. This results in a systematic decrease in Tg with the further decrease of the film thickness, below 30 nm. These results were discussed with respect to thin films of PVME/PS blend with a composition of 50/50 wt. % as well as literature results.

  12. 40 CFR Table 6 to Subpart Jj of... - VHAP of Potential Concern

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... glycol butyl ether, ethylene glycol ethyl ether (2-ethoxy ethanol), ethylene glycol hexyl ether, ethylene..., ethylene glycol mono-2-ethylhexyl ether, diethylene glycol butyl ether, diethylene glycol ethyl ether... glycol propyl ether, triethylene glycol butyl ether, triethylene glycol ethyl ether, triethylene glycol...

  13. Method for determination of methyl tert-butyl ether and its degradation products in water

    USGS Publications Warehouse

    Church, C.D.; Isabelle, L.M.; Pankow, J.F.; Rose, D.L.; Tratnyek, P.G.

    1997-01-01

    An analytical method is described that can detect the major alkyl ether compounds that are used as gasoline oxygenates (methyl tert-butyl ether, MTBE; ethyl tert-butyl ether, ETBE; and tert-amyl methyl ether, TAME) and their most characteristic degradation products (tert-butyl alcohol, TBA; tert-butyl formate, TBF; and tert-amyl alcohol, TAA) in water at sub-ppb concentrations. The new method involves gas chromatography (GC) with direct aqueous injection (DAI) onto a polar column via a splitless injector, coupled with detection by mass spectrometry (MS). DAI-GC/MS gives excellent agreement with conventional purge-and-trap methods for MTBE over a wide range of environmentally relevant concentrations. The new method can also give simultaneous identification of polar compounds that might occur as degradation products of gasoline oxygenates, such as TBA, TBF, TAA, methyl acetate, and acetone. When the method was applied to effluent from a column microcosm prepared with core material from an urban site in New Jersey, conversion of MTBE to TBA was observed after a lag period of 35 days. However, to date, analyses of water samples from six field sites using the DAI-GC/MS method have not produced evidence for the expected products of in situ degradation of MTBE.An analytical method is described that can detect the major alkyl ether compounds that are used as gasoline oxygenates (methyl tert-butyl ether, MTBE; ethyl tert-butyl ether, ETBE; and tert-amyl methyl ether, TAME) and their most characteristic degradation products (tert-butyl alcohol, TBA; tert-butyl formate, TBF; and tert-amyl alcohol, TAA) in water at sub-ppb concentrations. The new method involves gas chromatography (GC) with direct aqueous injection (DAI) onto a polar column via a splitless injector, coupled with detection by mass spectrometry (MS). DAI-GC/MS gives excellent agreement with conventional purge-and-trap methods for MTBE over a wide range of environmentally relevant concentrations. The new method

  14. Optimization of esterification of dicarboxylic acids and 2-ethyl-1-hexanol

    NASA Astrophysics Data System (ADS)

    Jafri, Nur Hafifah Nahdirah; Othman, Nor Hamidah Abu; Salimon, Jumat

    2018-04-01

    Dicarboxylate ester has the potential alternative as plasticizer which environmentally friendly in polymeric formulation especially for poly (vinyl chloride) (PVC). Dicarboxylate ester compounds were synthesized via esterification between dicarboxylic acid and 2-ethyl-1-hexanol by using sulfuric acid as catalyst. The effects of reaction parameters were studied by optimizing temperature, mole ratio of reactants, amount of catalyst and reaction to obtain highest ester conversion. The optimum results showed dicarboxylic acid successfully converted to the dicarboxylate ester at parameters; 4 hours; 120 °C; catalyst amount: 2% w/w of diacid; and mole ratio: 1:2.5. Functional group analysis was conducted by using ATR-FTIR spectroscopy.

  15. Characterization of the interaction between two food aroma components, alpha-pinene and ethyl butyrate, and ethylene-vinyl alcohol copolymer (EVOH) packaging films as a function of environmental humidity.

    PubMed

    López-Carballo, Gracia; Cava, David; Lagarón, Jose M; Catalá, Ramón; Gavara, Rafael

    2005-09-07

    The ethylene-vinyl alcohol copolymers (EVOHs) are well-known high oxygen barrier materials that are being used successfully in the design of packaging structures for oxygen-sensitive food or pharmaceutical products. Recently, there has been increasing interest in using EVOH materials to provide a high barrier to organic compounds as a means to reduce food aroma scalping. However, the barrier function of this family of materials diminishes significantly in humid environments, and it is supposed that so does the organic vapor barrier. In this work, a new sorption-based method to characterize the interaction between food aroma and polymer films for packaging as a function of relative humidity is presented and is used to determine the barrier to ethyl butyrate and alpha-pinene of EVOH at 23 degrees C. The results show that although EVOH is an excellent barrier to food aroma when dry, a property that even improves at low relative humidity (RH), the solubility and diffusivity of the compounds tested increase dramatically with humidity at medium to high water activities. However, even in the worst case (100% RH), EVOH outperforms low-density polyethylene (LDPE) as a barrier to organic vapors at least 500,000-fold.

  16. U.S. Geological Survey laboratory method for methyl tert-Butyl ether and other fuel oxygenates

    USGS Publications Warehouse

    Raese, Jon W.; Rose, Donna L.; Sandstrom, Mark W.

    1995-01-01

    Methyl tert-butyl ether (MTBE) was found in shallow ground-water samples in a study of 8 urban and 20 agricultural areas throughout the United States in 1993 and 1994 (Squillace and others, 1995, p. 1). The compound is added to gasoline either seasonally or year round in many parts of the United States to increase the octane level and to reduce carbon monoxide and ozone levels in the air. The U.S. Geological Survey (USGS) National Water Quality Laboratory (NWQL), near Denver, uses state-of-the-art technology to analyze samples for MTBE as part of the USGS water-quality studies. In addition, the NWQL offers custom analyses to determine two other fuel oxygenates--ethyl tert-butyl ether (ETBE) and tert-amyl methyl ether (TAME). The NWQL was not able to obtain a reference standard for tert-amyl ethyl ether (TAEE), another possible fuel oxygenate (Shelley and Fouhy, 1994, p. 63). The shallow ground-water samples were collected as part of the USGS National Water-Quality Assessment Program. These samples were collected from 211 urban wells or springs and 562 agricultural wells sampled by the USGS in 1993 and 1994. The wells were keyed to specific land-use areas to assess the effects of different uses on ground-water quality (Squillace and others, 1995, p. 2). Ground-water samples were preserved on site to pH less than or equal to 2 with a solution of 1:1 hydrochloric acid. All samples were analyzed at the NWQL within 2 weeks after collection. The purpose of this fact sheet is to explain briefly the analytical method implemented by the USGS for determining MTBE and other fuel oxygenates. The scope is necessarily limited to an overview of the analytical method (instrumentation, sample preparation, calibration and quantitation, identification, and preservation of samples) and method performance (reagent blanks, accuracy, and precision).

  17. Poly(arylene ether)s containing pendent ethynyl groups

    NASA Technical Reports Server (NTRS)

    Hergenrother, Paul M. (Inventor); Jensen, Brian J. (Inventor)

    1996-01-01

    Poly(arylene ether)s containing pendent ethynyl and substituted ethynyl groups and poly(arylene ether) copolymers containing pendent ethynyl and substituted ethynyl groups are readily prepared from bisphenols containing ethynyl and substituted ethynyl groups. The resulting polymers are cured up to 350.degree. C. to provide crosslinked poly(arylene ether)s with good solvent resistance, high strength and modulus.

  18. Poly(arylene ether)s containing pendent ethynyl groups

    NASA Technical Reports Server (NTRS)

    Hergenrother, Paul M. (Inventor); Jensen, Brian J. (Inventor)

    1994-01-01

    Poly(arylene ether)s containing pendent ethynyl and substituted ethynyl groups and poly(arylene ether) copolymers containing pendent ethynyl and substituted ethynyl groups are readily prepared from bisphenols containing ethynyl and substituted ethynyl groups. The resulting polymers are cured up to 350 C to provide crosslinked poly(arylene ether)s with good solvent resistance, high strength and modulus.

  19. [Chemical Constituents of Ethyl Acetate Fraction of Suaeda glauca].

    PubMed

    Qiu, Ping; Wang, Qi-zhi; Yin, Min; Wang, Ming; Zhao, You-yi; Shan, Yu; Feng, Xu

    2015-04-01

    To study the chemical constituents of Suaeda glauca. The chemical constituents were isolated and purified with several separation and purification techniques. Their structures were identified by physicochemical properties and various spectroscopic methods. Ten compounds were isolated from the ethyl acetate fraction as lignoceric acid (1), β-amyrin-n-nonyl ether(2), β-sitosterol(3), β-daucosterol(4), quercetin(5), luteolin(6), luteolin-7-O-β-D-glucoside(7), isorhamnetin(8), scopoletin (9) and stigmasterol(10). Compounds 1, 2, 6, 7, 8, 9 and 10 are isolated from Suaeda genus for the first time and compounds 3 - 5 are isolated from this plant for the first time.

  20. Poly(ether ester) Ionomers as Water-Soluble Polymers for Material Extrusion Additive Manufacturing Processes.

    PubMed

    Pekkanen, Allison M; Zawaski, Callie; Stevenson, André T; Dickerman, Ross; Whittington, Abby R; Williams, Christopher B; Long, Timothy E

    2017-04-12

    Water-soluble polymers as sacrificial supports for additive manufacturing (AM) facilitate complex features in printed objects. Few water-soluble polymers beyond poly(vinyl alcohol) enable material extrusion AM. In this work, charged poly(ether ester)s with tailored rheological and mechanical properties serve as novel materials for extrusion-based AM at low temperatures. Melt transesterification of poly(ethylene glycol) (PEG, 8k) and dimethyl 5-sulfoisophthalate afforded poly(ether ester)s of sufficient molecular weight to impart mechanical integrity. Quantitative ion exchange provided a library of poly(ether ester)s with varying counterions, including both monovalent and divalent cations. Dynamic mechanical and tensile analysis revealed an insignificant difference in mechanical properties for these polymers below the melting temperature, suggesting an insignificant change in final part properties. Rheological analysis, however, revealed the advantageous effect of divalent countercations (Ca 2+ , Mg 2+ , and Zn 2+ ) in the melt state and exhibited an increase in viscosity of two orders of magnitude. Furthermore, time-temperature superposition identified an elevation in modulus, melt viscosity, and flow activation energy, suggesting intramolecular interactions between polymer chains and a higher apparent molecular weight. In particular, extrusion of poly(PEG 8k -co-CaSIP) revealed vast opportunities for extrusion AM of well-defined parts. The unique melt rheological properties highlighted these poly(ether ester) ionomers as ideal candidates for low-temperature material extrusion additive manufacturing of water-soluble parts.

  1. Developmental toxicity and structure/activity correlates of glycols and glycol ethers.

    PubMed Central

    Johnson, E M; Gabel, B E; Larson, J

    1984-01-01

    In recent years, the National Toxicology Program (NTP) has selected numerous glycol ethers for testing in routine laboratory mammals to ascertain the magnitude of their ability to injure the conceptus. From the lists available of ongoing and projected NTP test chemicals, a series of glycol ethers was selected for examination in vitro in the hydra assay. Also tested were additional chemicals of similar molecular configuration and/or composition. This short-term screening test placed the 14 glycols and glycol ethers tested into a rank order sequence according to their degree of hazard potential to developmental biology, i.e., their ability to interfere with the developmental events characteristic of all ontogenic systems. They were ranked according to the difference between the lowest dose or concentration overtly toxic to adults (A) and the lowest concentration interfering with development (D) of the artificial embryo of reaggregated adult hydra cells and the A/D ratio. Published data from mammalian studies were available for a few of the test chemicals, and in each instance the hydra assay was in direct agreement with the outcomes reported of the more elaborate and standard animal tests. Ethylene glycol and ethylene glycol monomethyl ether were shown by both standard evaluations in mammals, and by the hydra assay, to disrupt embryos only at or very near to their respective adult toxic doses, whereas the mono-ethyl ether perturbed development at approximately one-fifth of the lowest dose overtly toxic to adults.(ABSTRACT TRUNCATED AT 250 WORDS) Images FIGURE 1. A FIGURE 1. B FIGURE 1. C PMID:6499797

  2. 21 CFR 177.1360 - Ethylene-vinyl acetate-vinyl alcohol copolymers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Premarket Approval (HFS-200), Center for Food Safety and Applied Nutrition, Food and Drug Administration... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ethylene-vinyl acetate-vinyl alcohol copolymers. 177.1360 Section 177.1360 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  3. On the effect of Di-Ethyl-Ether (DEE) injection upon the cold starting of a biodiesel fuelled compression ignition engine

    NASA Astrophysics Data System (ADS)

    Clenci, Adrian; Niculescu, Rodica; Iorga-Simǎn, Victor; Tricǎ, Alina; Danlos, Amélie

    2017-02-01

    The use of biodiesel fuel in compression ignition engines has the potential to reduce CO2, which can lead to a reduction in global warming and environmental hazards. Biodiesel is an attractive fuel, as it is made from renewable resources. A major drawback associated with the use of biodiesel, however, is its poor cold flow properties, which have a direct influence on the cold starting performance of the engine. This paper is a consequence of a study on assessing the cold-starting performance of a compression ignition engine fueled with different blends of fossil diesel fuel and biodiesel. Through experimental investigations, it was found that the engine starting at -20°C was no longer possible in the case of using B50 (50% diesel + 50% biofuel made from sunflower oil). In order to "force" the engine starting in this particular situation, Di-Ethyl-Ether (DEE) was injected into the intake manifold. DEE being a highly flammable substance, the result was a sudden and explosive engine starting, the peak pressure in the monitored cylinder in the first successful engine cycle being almost twice the one which is usually considered as normal. Thus, to explain the observed phenomena, we launched this work relying on the analysis of the in-cylinder instantaneous pressure evolution, which was acquired during cranking, stabilizing and idling phases. Moreover, since the cause of the sudden and explosive engine starting was the DEE, by using a CFD approach, we also obtained results regarding the inter-cylinder distribution of the injected DEE.

  4. Thermo-responsive cell culture carriers based on poly(vinyl methyl ether)-the effect of biomolecular ligands to balance cell adhesion and stimulated detachment.

    PubMed

    Teichmann, Juliane; Nitschke, Mirko; Pette, Dagmar; Valtink, Monika; Gramm, Stefan; Härtel, Frauke V; Noll, Thomas; Funk, Richard H W; Engelmann, Katrin; Werner, Carsten

    2015-08-01

    Two established material systems for thermally stimulated detachment of adherent cells were combined in a cross-linked polymer blend to merge favorable properties. Through this approach poly( N -isopropylacrylamide) (PNiPAAm) with its superior switching characteristic was paired with a poly(vinyl methyl ether)-based composition that allows adjusting physico-chemical and biomolecular properties in a wide range. Beyond pure PNiPAAm, the proposed thermo-responsive coating provides thickness, stiffness and swelling behavior, as well as an apposite density of reactive sites for biomolecular functionalization, as effective tuning parameters to meet specific requirements of a particular cell type regarding initial adhesion and ease of detachment. To illustrate the strength of this approach, the novel cell culture carrier was applied to generate transplantable sheets of human corneal endothelial cells (HCEC). Sheets were grown, detached, and transferred onto planar targets. Cell morphology, viability and functionality were analyzed by immunocytochemistry and determination of transepithelial electrical resistance (TEER) before and after sheet detachment and transfer. HCEC layers showed regular morphology with appropriate TEER. Cells were positive for function-associated marker proteins ZO-1, Na + /K + -ATPase, and paxillin, and extracellular matrix proteins fibronectin, laminin and collagen type IV before and after transfer. Sheet detachment and transfer did not impair cell viability. Subsequently, a potential application in ophthalmology was demonstrated by transplantation onto de-endothelialized porcine corneas in vitro . The novel thermo-responsive cell culture carrier facilitates the generation and transfer of functional HCEC sheets. This paves the way to generate tissue engineered human corneal endothelium as an alternative transplant source for endothelial keratoplasty.

  5. Sensitivity of infectious bovine rhinotracheitis virus to ether.

    PubMed

    Crandell, R A; Melloh, A J; Sorlie, P

    1975-12-01

    The sensitivity of 12 field isolates of infectious boviine rhinotracheitis (IBR) virus and four commercial modified-live infectious bovine rhinotracheitis virus vaccine strains was determined after exposure to 20% ethyl ether (anesthetic) for 16 h at 4 c. The infectivity of five field strains was reduced by varying degrees, whereas seven were found to be resistant. Three vaccine strains were moderately sensitive, and one strain was resistant. Four of the sensitive field strains were isolated from the conjunctiva and the other was isolated from the surface of the epiglottis of natural infective cattle. Strains of virus isolated from fetal tissue and nasal cavity were resistant. All viruses were readily inactivated by chloroform treatment.

  6. DIPPR Project 871 For 1995 - Thermodynamic Properties and Ideal-Gas Enthalpies of Formation for Methyl Benzoate, Ethyl Benzoate, (R)-(+)-Limonene, Tert-Amyl Methyl Ether, Trans-Crotonaldehyde, and

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Steele, W.V.

    2002-07-01

    Ideal-gas enthalpies of formation of methyl benzoate, ethyl benzoate, (R)-(+)-limonene, tert-amyl methyl ether, trans-crotonaldehyde, and diethylene glycol are reported. The standard energy of combustion and hence standard enthalpy of formation of each compound in the liquid phase has been measured using an oxygen rotating-bomb calorimeter without rotation. Vapor pressures were measured to a pressure limit of 270 kPa or the lower decomposition point for each of the six compounds using a twin ebulliometric apparatus. Liquid-phase densities along the saturation line were measured for each compound over a range of temperature (ambient to a maximum of 548 K). A differential scanningmore » calorimeter was used to measure two-phase (liquid + vapor) heat capacities for each compound in the temperature region ambient to the critical temperature or lower decomposition point. For methyl benzoate and tert-amyl methyl ether, critical temperatures and critical densities were determined from the DSC results and corresponding critical pressures derived from the fitting procedures. Fitting procedures were used to derive critical temperatures, critical pressures, and critical densities for each of the remaining compounds. The results of the measurements were combined to derive a series of thermophysical properties including critical temperature, critical density, critical pressure, acentric factor, enthalpies of vaporization (restricted to within {+-}50 K of the temperature region of the experimentally determined vapor pressures), and heat capacities along the saturation line. Wagner-type vapor-pressure equations were derived for each compound. All measured and derived values were compared with those obtained in a search of the literature. Recommended critical parameters are listed for each of the compounds studied. Group-additivity parameters, useful in the application of the Benson gas-phase group-contribution correlations, were derived.« less

  7. No Promoting Effect of Ethyl Tertiary-butyl Ether (ETBE) on Rat Urinary Bladder Carcinogenesis Initiated with N-Butyl-N-(4-hydroxybutyl)nitrosamine

    PubMed Central

    Hagiwara, Akihiro; Imai, Norio; Doi, Yuko; Suguro, Mayuko; Kawabe, Mayumi; Furukawa, Fumio; Nagano, Kasuke; Fukushima, Shoji

    2013-01-01

    The effects of ethyl tertiary-butyl ether (ETBE) on two-stage urinary bladder carcinogenesis in male F344 rats initiated with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) were investigated at various dose levels with regard to possible promoting activity. Groups of 30 rats were given drinking water containing 500 ppm BBN, as an initiator, for 4 weeks and starting one week thereafter received ETBE by gavage (daily, 7 days/week) at dose levels of 0 (control), 100, 300, 500 or 1000 mg/kg/day until experimental week 36. No statistically significant differences in incidences of preneoplastic lesions, papillomas, and carcinomas of the urinary bladder were evident in rats treated with 100–1000 mg/kg/day ETBE as compared with control values. Furthermore, the average numbers of preneoplastic or neoplastic lesions per unit length of basement membrane in rats given 100–1000 mg/kg/day ETBE were also comparable to control values. However, papillomatosis of the urinary bladder was found in 4 out of 30 rats (13%) in the group given 1000 mg/kg/day ETBE, and soft stones in the urinary bladder were found in 3 out of these 4 rats. The results thus demonstrated that ETBE did not exert promotional activity on urinary bladder carcinogenesis. However, papillomatosis of the urinary bladder developed in small numbers of the rats given ETBE at 1000 mg/kg/day but not in rats given 500 mg/kg/day or lower doses. PMID:24526807

  8. Catalyst activity maintenance study for the liquid phase dimethyl ether process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peng, X.D.; Toseland, B.A.; Underwood, R.P.

    1995-12-31

    The co-production of dimethyl ether (DME) and methanol from syngas is a process of considerable commercial attractiveness. DME coproduction can double the productivity of a LPMEOH process when using coal-derived syngas. This in itself may offer chemical producers and power companies increased flexibility and more profitable operation. DME is also known as a clean burning liquid fuel; Amoco and Haldor-Topsoe have recently announced the use of DME as an alternative diesel fuel. Moreover, DME can be an interesting intermediate in the production of chemicals such as olefins and vinyl acetate. The current APCl liquid phase dimethyl ether (LPDME) process utilizesmore » a physical mixture of a commercial methanol synthesis catalyst and a dehydration catalyst (e.g., {gamma}-alumina). While this arrangement provides a synergy that results in much higher syngas conversion per pass compared to the methanol-only process, the stability of the catalyst system suffers. The present project is aimed at reducing catalyst deactivation both by understanding the cause(s) of catalyst deactivation and by developing modified catalyst systems. This paper describes the current understanding of the deactivation mechanism.« less

  9. Lack of micronucleus induction activity of ethyl tertiary-butyl ether in the bone marrow of F344 rats by sub-chronic drinking-water treatment, inhalation exposure, or acute intraperitoneal injection.

    PubMed

    Noguchi, Tadashi; Kamigaito, Tomoyuki; Katagiri, Taku; Kondou, Hitomi; Yamazaki, Kazunori; Aiso, Shigetoshi; Nishizawa, Tomoshi; Nagano, Kasuke; Fukushima, Shoji

    2013-01-01

    Ethyl tertiary-butyl ether (ETBE) is an oxygenated gasoline additive synthesized from ethanol and isobutene that is used to reduce CO2 emissions. To support the Kyoto Protocol, the production of ETBE has undergone a marked increase. Previous reports have indicated that exposure to ETBE or methyl tertiary-butyl ether resulted in liver and kidney tumors in rats and/or mice. These reports raise concern about the effects of human exposure being brought about by the increased use of ETBE. The present study was conducted to evaluate the genotoxicity of ETBE using micronucleus induction of polychromatic erythrocytes in the bone marrow of male and female rats treated with ETBE in the drinking-water at concentrations of 0, 1,600, 4,000 or 10,000 ppm or exposed to ETBE vapor at 0, 500, 1,500 or 5,000 ppm for 13 weeks. There were no significant increases in micronucleus induction in either the drinking water-administered or inhalation-administered groups at any concentration of ETBE; although, in both groups red blood cells and hemoglobin concentration were slightly reduced in the peripheral blood in rats administered the highest concentration of ETBE. In addition, two consecutive daily intraperitoneal injections of ETBE at doses of 0, 250, 500 or 1,000 mg/kg did not increase the frequency of micronucleated bone marrow cells in either sex; all rats receiving intraperitoneal injections of ETBE at a dose of 2,000 mg/kg died after treatment day 1. These data suggest that ETBE is not genotoxic in vivo.

  10. The effect of polymer aging on the uptake of fuel aromatics and ethers by microplastics.

    PubMed

    Müller, Axel; Becker, Roland; Dorgerloh, Ute; Simon, Franz-Georg; Braun, Ulrike

    2018-05-14

    Microplastics are increasingly entering marine, limnic and terrestrial ecosystems worldwide, where they sorb hydrophobic organic contaminants. Here, the sorption behavior of the fuel-related water contaminants benzene, toluene, ethyl benzene and xylene (BTEX) and four tertiary butyl ethers to virgin and via UV radiation aged polypropylene (PP) and polystyrene (PS) pellets was investigated. Changes in material properties due to aging were recorded using appropriate polymer characterization methods, such as differential scanning calorimetry, Fourier transform infrared spectroscopy, gel permeation chromatography, X-ray photoelectron spectroscopy, and microscopy. Pellets were exposed to water containing BTEX and the ethers at 130-190 μg L -1 for up to two weeks. Aqueous sorbate concentrations were determined by headspace gas chromatography. Sorption to the polymers was correlated with the sorbate's K ow and was significant for BTEX and marginal for the ethers. Due to substantially lower glass transition temperatures, PP showed higher sorption than PS. Aging had no effect on the sorption behavior of PP. PS sorbed less BTEX after aging due to an oxidized surface layer. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Sulfonimide-containing poly(arylene ether)s and poly(arylene ether sulfone)s, methods for producing the same, and uses thereof

    DOEpatents

    Hofmann, Michael A.

    2006-11-14

    The present invention is directed to sulfonimide-containing polymers, specifically sulfonimide-containing poly(arylene ether)s and sulfonimide-containing poly(arylene ether sulfone)s, and processes for making the sulfonimide-containing poly(arylene ether)s and sulfonimide-containing poly(arylene ether sulfone)s, for use conductive membranes and fuel cells.

  12. Thermo-responsive cell culture carriers based on poly(vinyl methyl ether)—the effect of biomolecular ligands to balance cell adhesion and stimulated detachment

    NASA Astrophysics Data System (ADS)

    Teichmann, Juliane; Nitschke, Mirko; Pette, Dagmar; Valtink, Monika; Gramm, Stefan; Härtel, Frauke V.; Noll, Thomas; Funk, Richard H. W.; Engelmann, Katrin; Werner, Carsten

    2015-08-01

    Two established material systems for thermally stimulated detachment of adherent cells were combined in a cross-linked polymer blend to merge favorable properties. Through this approach poly(N-isopropylacrylamide) (PNiPAAm) with its superior switching characteristic was paired with a poly(vinyl methyl ether)-based composition that allows adjusting physico-chemical and biomolecular properties in a wide range. Beyond pure PNiPAAm, the proposed thermo-responsive coating provides thickness, stiffness and swelling behavior, as well as an apposite density of reactive sites for biomolecular functionalization, as effective tuning parameters to meet specific requirements of a particular cell type regarding initial adhesion and ease of detachment. To illustrate the strength of this approach, the novel cell culture carrier was applied to generate transplantable sheets of human corneal endothelial cells (HCEC). Sheets were grown, detached, and transferred onto planar targets. Cell morphology, viability and functionality were analyzed by immunocytochemistry and determination of transepithelial electrical resistance (TEER) before and after sheet detachment and transfer. HCEC layers showed regular morphology with appropriate TEER. Cells were positive for function-associated marker proteins ZO-1, Na+/K+-ATPase, and paxillin, and extracellular matrix proteins fibronectin, laminin and collagen type IV before and after transfer. Sheet detachment and transfer did not impair cell viability. Subsequently, a potential application in ophthalmology was demonstrated by transplantation onto de-endothelialized porcine corneas in vitro. The novel thermo-responsive cell culture carrier facilitates the generation and transfer of functional HCEC sheets. This paves the way to generate tissue engineered human corneal endothelium as an alternative transplant source for endothelial keratoplasty.

  13. Thermo-responsive cell culture carriers based on poly(vinyl methyl ether)—the effect of biomolecular ligands to balance cell adhesion and stimulated detachment

    PubMed Central

    Teichmann, Juliane; Nitschke, Mirko; Pette, Dagmar; Valtink, Monika; Gramm, Stefan; Härtel, Frauke V; Noll, Thomas; Funk, Richard H W; Engelmann, Katrin; Werner, Carsten

    2015-01-01

    Two established material systems for thermally stimulated detachment of adherent cells were combined in a cross-linked polymer blend to merge favorable properties. Through this approach poly(N-isopropylacrylamide) (PNiPAAm) with its superior switching characteristic was paired with a poly(vinyl methyl ether)-based composition that allows adjusting physico-chemical and biomolecular properties in a wide range. Beyond pure PNiPAAm, the proposed thermo-responsive coating provides thickness, stiffness and swelling behavior, as well as an apposite density of reactive sites for biomolecular functionalization, as effective tuning parameters to meet specific requirements of a particular cell type regarding initial adhesion and ease of detachment. To illustrate the strength of this approach, the novel cell culture carrier was applied to generate transplantable sheets of human corneal endothelial cells (HCEC). Sheets were grown, detached, and transferred onto planar targets. Cell morphology, viability and functionality were analyzed by immunocytochemistry and determination of transepithelial electrical resistance (TEER) before and after sheet detachment and transfer. HCEC layers showed regular morphology with appropriate TEER. Cells were positive for function-associated marker proteins ZO-1, Na+/K+-ATPase, and paxillin, and extracellular matrix proteins fibronectin, laminin and collagen type IV before and after transfer. Sheet detachment and transfer did not impair cell viability. Subsequently, a potential application in ophthalmology was demonstrated by transplantation onto de-endothelialized porcine corneas in vitro. The novel thermo-responsive cell culture carrier facilitates the generation and transfer of functional HCEC sheets. This paves the way to generate tissue engineered human corneal endothelium as an alternative transplant source for endothelial keratoplasty. PMID:27877823

  14. Microbial reductive dehalogenation of vinyl chloride

    DOEpatents

    Spormann, Alfred M [Stanford, CA; Muller, Jochen A [Baltimore, MD; Rosner, Bettina M [Berlin, DE; Von Abendroth, Gregory [Nannhein, DE; Meshulam-Simon, Galit [Los Altos, CA; McCarty, Perry L [Stanford, CA

    2011-11-22

    Compositions and methods are provided that relate to the bioremediation of chlorinated ethenes, particularly the bioremediation of vinyl chloride by Dehalococcoides-like organisms. An isolated strain of bacteria, Dehalococcoides sp. strain VS, that metabolizes vinyl chloride is provided; the genetic sequence of the enzyme responsible for vinyl chloride dehalogenation; methods of assessing the capability of endogenous organisms at an environmental site to metabolize vinyl chloride; and a method of using the strains of the invention for bioremediation.

  15. Microbial reductive dehalogenation of vinyl chloride

    DOEpatents

    Spormann, Alfred M [Stanford, CA; Muller, Jochen A [Baltimore, MD; Rosner, Bettina M [Berlin, DE; Von Abendroth, Gregory [Mannheim, DE; Meshulam-Simon, Galit [Los Angeles, CA; McCarty, Perry L [Stanford, CA

    2014-02-11

    Compositions and methods are provided that relate to the bioremediation of chlorinated ethenes, particularly the bioremediation of vinyl chloride by Dehalococcoides-like organisms. An isolated strain of bacteria, Dehalococcoides sp. strain VS, that metabolizes vinyl chloride is provided; the genetic sequence of the enzyme responsible for vinyl chloride dehalogenation; methods of assessing the capability of endogenous organisms at an environmental site to metabolize vinyl chloride; and a method of using the strains of the invention for bioremediation.

  16. The Chirped-Pulse Fourier Transform Microwave Cp-Ftmw Spectrum and Potential Energy Calculations for AN Aromatic Claisen Rearrangement Molecule, Allyl Phenyl Ether

    NASA Astrophysics Data System (ADS)

    Grubbs, G. S. Grubbs, Ii; Cooke, S. A.; Novick, Stewart E.

    2012-06-01

    Claisen rearrangement ethers are a fundamental organic, pericyclic rearrangement reaction reagent. In the mechanism of a Claisen rearrangement, a vinyl allyl ether is needed to provide the necessary Lewis acid/base sites on the molecule for the rearrangement and are simply heated. This rearrangement was first discovered by heating up the title molecule, allyl phenyl ether. However, much like the Diels-Alder, Cope, and other pericyclic reactions, conformation and coordination of chemical groups is key to the Claisen mechanism. In this study, the authors present some structural characteristics of allyl phenyl ether from an analysis of the microwave spectra in the 8-14 GHz region using a CP-FTMW spectrometer. This is, to the authors knowledge, the first known microwave region study of the title molecule. Three conformers have been observed and assigned to date and will be discussed. Along with the rotational spectra, geometry calculations and potential energy surfaces performed at the MP2/6-311G++(3d,2p) level will be discussed and compared to the experimental results. Modeling the Claisen aromatic rearrangement mechanism using CP-FTMW spectroscopy will also be discussed. L. Claisen Chemische Berichte 45, 3157, October 1912.

  17. Preparation of vinyl acetate

    DOEpatents

    Tustin, Gerald Charles; Zoeller, Joseph Robert; Depew, Leslie Sharon

    1998-01-01

    This invention pertains to the preparation of vinyl acetate by contacting a mixture of hydrogen and ketene with a heterogeneous catalyst containing a transition metal to produce acetaldehyde, which is then reacted with ketene in the presence of an acid catalyst to produce vinyl acetate.

  18. Preparation of vinyl acetate

    DOEpatents

    Tustin, G.C.; Zoeller, J.R.; Depew, L.S.

    1998-03-24

    This invention pertains to the preparation of vinyl acetate by contacting a mixture of hydrogen and ketene with a heterogeneous catalyst containing a transition metal to produce acetaldehyde, which is then reacted with ketene in the presence of an acid catalyst to produce vinyl acetate.

  19. Chemical bonding and the equilibrium composition of Grignard reagents in ethereal solutions.

    PubMed

    Henriques, André M; Barbosa, André G H

    2011-11-10

    A thorough analysis of the electronic structure and thermodynamic aspects of Grignard reagents and its associated equilibrium composition in ethereal solutions is performed. Considering methylmagnesium halides containing fluorine, chlorine, and bromine, we studied the neutral, charged, and radical species associated with their chemical equilibrium in solution. The ethereal solvents considered, tetrahydrofuran (THF) and ethyl ether (Et(2)O), were modeled using the polarizable continuum model (PCM) and also by explicit coordination to the Mg atoms in a cluster. The chemical bonding of the species that constitute the Grignard reagent is analyzed in detail with generalized valence bond (GVB) wave functions. Equilibrium constants were calculated with the DFT/M06 functional and GVB wave functions, yielding similar results. According to our calculations and existing kinetic and electrochemical evidence, the species R(•), R(-), (•)MgX, and RMgX(2)(-) must be present in low concentration in the equilibrium. We conclude that depending on the halogen, a different route must be followed to produce the relevant equilibrium species in each case. Chloride and bromide must preferably follow a "radical-based" pathway, and fluoride must follow a "carbanionic-based" pathway. These different mechanisms are contrasted against the available experimental results and are proven to be consistent with the existing thermodynamic data on the Grignard reagent equilibria.

  20. Constraining the Molecular Complexity in the Interstellar Medium—The Formation of Ethyl Methyl Ether (CH3OCH2CH3) in Star-forming Regions

    NASA Astrophysics Data System (ADS)

    Bergantini, Alexandre; Frigge, Robert; Kaiser, Ralf I.

    2018-05-01

    We report the first confirmed synthesis of ethyl methyl ether (EME, CH3CH2OCH3) within astrophysical model ices containing water (H2O) and methane (CH4) exposed to ionizing radiation at ultra-low temperatures of 5 K. EME (also known as methoxyethane), was recently observed toward Orion KL and currently is the largest confirmed oxygen-bearing molecule found in the interstellar medium. Exploiting isomer-selective photoionization (PI) of the subliming molecules in the temperature-programmed desorption phase at 10.49, 9.92, and 9.70 eV, coupled with reflectron time-of-flight mass spectrometry and isotopic substitution experiments (H2 18O–CH4), the detection of fragment ions of EME at m/z = 45 (C2H5O+) and m/z = 59 (C3H7O+), and probing the proton transfer in subliming ethanol–EME complexes via m/z = 61 (C3H9O+), the present study reveals that EME can be formed from suprathermal reactions initiated by cosmic rays and secondary electrons generated within astrophysical ices. The detection of EME in our experiments represents a significant advance in the understanding of formation pathways of complex organic molecules present in hot cores and helps to constrain astrochemical models on the formation of such species within molecular clouds.

  1. Infrared study of matrix-isolated ethyl cyanide: simulation of the photochemistry in the atmosphere of Titan.

    PubMed

    Toumi, A; Piétri, N; Couturier-Tamburelli, I

    2015-11-11

    Low-temperature Ar matrix isolation has been carried out to investigate the infrared spectrum of ethyl cyanide (CH3CH2CN), a molecule present in the atmosphere of Titan. The λ > 120 nm and λ > 230 nm photolysis reactions of ethyl cyanide in an Ar matrix were also performed in order to compare the behaviour of this compound when it is submitted to high and low energetic radiations. These different wavelengths have been used with the aim to reproduce the radiation reaching the various parts of the atmosphere. Several photoproducts have been identified during photolysis such as vinyl cyanide (CH2[double bond, length as m-dash]CHCN), cyanoacetylene (HC3N), and ethylene/hydrogen cyanide (C2H4/HCN), ethylene/hydrogen isocyanide (C2H4/HNC), acetylene/hydrogen cyanide (C2H2/HCN), acetylene/hydrogen isocyanide (C2H2/HNC), and acetylene:methylenimine (C2H2:HNCH2) complexes. Ethyl isocyanide (CH3CH2NC) and a ketenimine form (CH3CH[double bond, length as m-dash]C[double bond, length as m-dash]NH) have been identified as well. Photoproduct identification and spectral assignments were done using previous studies and density functional theory (DFT) calculations with the B3LYP/cc-pVTZ basis set.

  2. Decoration of a Poly(methyl vinyl ether-co-maleic anhydride)-Shelled Selol Nanocapsule with Folic Acid Increases Its Activity Against Different Cancer Cell Lines In Vitro.

    PubMed

    Ganassin, Rayane; Souza, Ludmilla Regina de; Py-Daniel, Karen Rapp; Longo, João Paulo Figueiró; Coelho, Janaína Moreira; Rodrigues, Mosar Correa; Jiang, Cheng-Shi; Gu, Jinsong; Morais, Paulo César de; Mosiniewicz-Szablewska, Ewa; Suchocki, Piotr; Báo, Sônia Nair; Azevedo, Ricardo Bentes; Muehlmann, Luis Alexandre

    2018-01-01

    Due to the low therapeutic index of different chemotherapeutic drugs used for cancer treatment, the development of new anticancer drugs remains an intense field of research. A recently developed mixture of selenitetriacylglycerides, selol, was shown to be active against different cancer cells in vitro. As this compound is highly hydrophobic, it was encapsulated, in a previous study, into poly(methyl vinyl ether-co-maleic anhydride)-shelled nanocapsules in order to improve its dispersibility in aqueous media. Following this line of research, the present report aimed at enhancing the In Vitro activity of the selol nanocapsules against cancerous cells by decorating their surface with folic acid. It is known that several cancer cells overexpress folate receptors. Stable folic acid-decorated selol nanocapsules (SNP-FA) were obtained, which showed to be spherical, with a hydro-dynamic diameter of 364 nm, and zeta potential of -24 mV. In comparison to non-decorated selol nanocapsules, SNP-FA presented higher activity against 4T1, MCF-7 and HeLa cells. Moreover, the decoration of the nanocapsules did not alter their toxicity towards fibroblasts, NIH-3T3 cells. These results show that the decoration with folic acid increased the toxicity of selol nanocapsules to cancer cells. These nanocapsules, besides enabling to disperse selol in an aqueous medium, increased the toxicity of this drug In Vitro, and may be useful to treat cancer in vivo, potentially increasing the specificity of selol towards cancer cells.

  3. 42 CFR 84.250 - Vinyl chloride respirators; description.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Vinyl chloride respirators; description. 84.250... Respirators § 84.250 Vinyl chloride respirators; description. Vinyl chloride respirators, including all... escape from vinyl chloride atmospheres containing adequate oxygen to support life, are described...

  4. Preparation of Syndiotactic Poly(vinyl alcohol)/Poly(vinyl pivalate/vinyl acetate) Microspheres with Radiopacity Using Suspension Copolymerization and Saponification

    NASA Astrophysics Data System (ADS)

    Seok Lyoo, Won; Wook Cha, Jin; Young Kwak, Kun; Jae Lee, Young; Yong Jeon, Han; Sik Chung, Yong; Kyun Noh, Seok

    2010-06-01

    To prepare Poly(vinyl pivalate/vinyl acetate) [P(VPi/VAc)] microspheres with radiopacity, the suspension copolymerization approach in the presence of aqueous radiopaque nanoparticles was used. After, The P(VPi/VAc) microspheres with radiopacity were saponified in heterogeneous system, and then P(VPi/VAc) microspheres without aggregates were converted to s-PVA/P(VPi/VAc) microspheres of skin/core structure through the heterogeneous surface saponification. Radiopacity of microspheres was confirmed with Computed tomography (CT).

  5. 21 CFR 175.270 - Poly(vinyl fluoride) resins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... polymerization of vinyl fluoride. (b) The poly(vinyl fluoride) basic resins have an intrinsic viscosity of not... Dilute Solution Viscosity of Vinyl Chloride Polymers,” which is incorporated by reference. Copies may be... Solution Viscosity of Vinyl Chloride Polymers,” which is incorporated by reference; see paragraph (b) of...

  6. 21 CFR 175.270 - Poly(vinyl fluoride) resins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... polymerization of vinyl fluoride. (b) The poly(vinyl fluoride) basic resins have an intrinsic viscosity of not... Dilute Solution Viscosity of Vinyl Chloride Polymers,” which is incorporated by reference. Copies may be... Solution Viscosity of Vinyl Chloride Polymers,” which is incorporated by reference; see paragraph (b) of...

  7. 21 CFR 175.270 - Poly(vinyl fluoride) resins.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Poly(vinyl fluoride) resins. 175.270 Section 175... Substances for Use as Components of Coatings § 175.270 Poly(vinyl fluoride) resins. Poly(vinyl fluoride... the purpose of this section, poly(vinyl fluoride) resins consist of basic resins produced by the...

  8. 21 CFR 175.270 - Poly(vinyl fluoride) resins.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Poly(vinyl fluoride) resins. 175.270 Section 175... Substances for Use as Components of Coatings § 175.270 Poly(vinyl fluoride) resins. Poly(vinyl fluoride... the purpose of this section, poly(vinyl fluoride) resins consist of basic resins produced by the...

  9. MECHANICAL PROPERTIES OF BLENDS OF PAMAM DENDRIMERS WITH POLY(VINYL CHLORIDE) AND POLY(VINYL ACETATE)

    EPA Science Inventory

    Hybrid blends of poly(amidoamine) PAMAM dendrimers with two linear high polymers, poly(vinyl chloride), PVC, and poly(vinyl acetate), PVAc, are reported. The interaction between the blend components was studied using dynamic mechanical analysis, xenon nuclear magnetic resonacne ...

  10. Sinopestalotiollides A-D, cytotoxic diphenyl ether derivatives from plant endophytic fungus Pestalotiopsis palmarum.

    PubMed

    Xiao, Jian; Hu, Jia-Yao; Sun, Hao-Dong; Zhao, Xiang; Zhong, Wan-Tong; Duan, Dong-Zhu; Wang, Le; Wang, Xiao-Ling

    2017-11-28

    Four new diphenyl ether derivatives, sinopestalotiollides A-D (1-4), one new natural α-pyrone product (11), as well as twelve known compounds (5-1 7), were obtained from the ethyl acetate extract of the endophytic fungus Pestalotiopsis palmarum isolated from the leaves of medicinal plant Sinomenium acutum (Thunb.) Rehd et Wils. The structures were elucidated by HR-ESI-MS and NMR spectrometry data. Bioassay experiments revealed that compounds 1-4 and 11 exhibited strong to weak cytotoxicities against three human tumor cell lines Hela, HCT116 and A549. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. 40 CFR 721.3140 - Vinyl epoxy ester.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Vinyl epoxy ester. 721.3140 Section... Substances § 721.3140 Vinyl epoxy ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance vinyl epoxy ester (PMN P-85-527) is subject to reporting under this...

  12. 40 CFR 721.3140 - Vinyl epoxy ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Vinyl epoxy ester. 721.3140 Section... Substances § 721.3140 Vinyl epoxy ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance vinyl epoxy ester (PMN P-85-527) is subject to reporting under this...

  13. 40 CFR 721.3140 - Vinyl epoxy ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Vinyl epoxy ester. 721.3140 Section... Substances § 721.3140 Vinyl epoxy ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance vinyl epoxy ester (PMN P-85-527) is subject to reporting under this...

  14. 40 CFR 721.3140 - Vinyl epoxy ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Vinyl epoxy ester. 721.3140 Section... Substances § 721.3140 Vinyl epoxy ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance vinyl epoxy ester (PMN P-85-527) is subject to reporting under this...

  15. 40 CFR 721.3140 - Vinyl epoxy ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Vinyl epoxy ester. 721.3140 Section... Substances § 721.3140 Vinyl epoxy ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance vinyl epoxy ester (PMN P-85-527) is subject to reporting under this...

  16. N-alkyl pyrrolidone ether podands as versatile alkali metal ion chelants.

    PubMed

    Perrin, Andrea; Myers, Dominic; Fucke, Katharina; Musa, Osama M; Steed, Jonathan W

    2014-02-28

    This work explores the coordination chemistry of a bis(pyrrolidone) ether ligand. Pyrrolidones are commercially important functional groups because of the high polarity and hence high hydrophilicity and surface affinity. An array of alkali metal ion complexes of a podand bearing two pendant pyrrolidone functionalities, namely 1-{2-[2-(2-oxo-pyrrolid-1-yl)-ethoxy]-ethyl}-pyrrolid-2-one (1) are reported. Reaction of this ligand with sodium hexafluorophosphate gives two discrete species of formulae [Na(1)2]PF6 (3) and [Na3(H2O)2(μ-1)2](PF6)3 (4), and a coordination polymer {[Na3(μ3-1)3(μ2-1)](PF6)3}n (5). The same reaction in methanol gives a 1 : 1 complex, namely [Na2(μ-1)2(MeOH)2](PF6)2 (6). Use of tetraphenyl borate as a less coordinating counter ion gives [Na2(1)2(H2O)4](BPh4)2 (7) and [Na2(1)4](BPh4)2 (8). Two potassium complexes have also been isolated, a monomer [K(1)2]PF6 (9) and a cyclic tetramer [K4(μ4-H2O)2(μ-1)4](PF6)4 (10). The structures illustrate the highly polar nature of the amide carbonyl moiety within bis(pyrrolidone) ethers with longer interactions to the ether oxygen atom. The zinc complex is also reported and {[ZnCl2(μ-1)]}n (11) exhibits bonding only to the carbonyl moieties. The ether oxygen atom is not necessary for Na(+) complexation as exemplified by the structure of the sodium complex of the analogue 1,3-bis(pyrrolid-2-on-1-yl)butane (2). Reaction of compound 1 with lithium salts results in isolation of the protonated ligand.

  17. THE SEARCH FOR A COMPLEX MOLECULE IN A SELECTED HOT CORE REGION: A RIGOROUS ATTEMPT TO CONFIRM TRANS-ETHYL METHYL ETHER TOWARD W51 e1/e2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carroll, P. Brandon; McGuire, Brett A.; Blake, Geoffrey A.

    2015-01-20

    An extensive search has been conducted to confirm transitions of trans-ethyl methyl ether (tEME, C{sub 2}H{sub 5}OCH{sub 3}), toward the high-mass star forming region W51 e1/e2 using the 12 m Telescope of the Arizona Radio Observatory at wavelengths from 2 mm and 3 mm. In short, we cannot confirm the detection of tEME toward W51 e1/e2 and our results call into question the initial identification of this species by Fuchs et al. Additionally, re-evaluation of the data from the original detection indicates that tEME is not present toward W51 e1/e2 in the abundance reported by Fuchs and colleagues. Typical peak-to-peak noise levels for themore » present observations of W51 e1/e2 were between 10 and 30 mK, yielding an upper limit of the tEME column density of ≤1.5 × 10{sup 15} cm{sup –2}. This would make tEME at least a factor of two times less abundant than dimethyl ether (CH{sub 3}OCH{sub 3}) toward W51 e1/e2. We also performed an extensive search for this species toward the high-mass star forming region Sgr B2(N-LMH) with the National Radio Astronomy Observatory 100 m Green Bank Telescope. No transitions of tEME were detected and we were able to set an upper limit to the tEME column density of ≤4 × 10{sup 14} cm{sup –2} toward this source. Thus, we are able to show that tEME is not a new molecular component of the interstellar medium and that an exacting assessment must be carried out when assigning transitions of new molecular species to astronomical spectra to support the identification of large organic interstellar molecules.« less

  18. Far-Infrared Spectroscopy of Anti-Vinyl Alcohol

    NASA Astrophysics Data System (ADS)

    Raston, Paul; Bunn, Hayley

    2016-06-01

    Vinyl alcohol can exist in two rotameric forms, known as syn- and anti- vinyl alcohol, where syn is the most stable. Both rotamers have been observed in the interstellar medium towards Sagittarius B2(N) making them of particular astrophysical importance. Vinyl alcohol has been subject to various spectroscopic investigations, however, the anti rotamer has only been obsvered in the microwave region. We report the high resolution (0.001 wn) FTIR spectrum of anti-vinyl alcohol collected at the infrared beamline facility of the Australian Synchrotron. Vinyl alcohol was produced via the pyrolysis of 2-chloroethanol at 900°C, and its far infrared spectrum reveals the presence of the strong νb{15} fundamental and hot band of anti-vinyl alcohol. Rotational and centrifugal distortion constants of this higher energy rotamer have since been determined for the νb{15} and 2νb{15} states, and the ground state constants have been refined. B. E. Turner, A. J. Apponi, ApJ 561, 207 (2001) M. Rodler, J. Mol. Spec. 114, 23 (1985) D-L Joo, et al., J. Mol. Spec. 197, 68 (1999)

  19. 46 CFR 154.1745 - Vinyl chloride: Transferring operations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Vinyl chloride: Transferring operations. 154.1745 Section 154.1745 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS... Operating Requirements § 154.1745 Vinyl chloride: Transferring operations. A vessel carrying vinyl chloride...

  20. Pure Rotational Spectroscopy of Vinyl Mercaptan

    NASA Astrophysics Data System (ADS)

    Martin-Drumel, Marie-Aline; Zingsheim, Oliver; Thorwirth, Sven; Müller, Holger S. P.; Lewen, Frank; Schlemmer, Stephan

    2014-06-01

    Vinyl mercaptan (ethenethiol, CH_2=CHSH) exists in the gas phase in two distinct rotameric forms, syn (planar) and anti (quasi-planar in the ground vibrational state). The microwave spectra of these two isomers were investigated previously, however not exceeding frequencies of about 65 GHz. In the present investigation, the pure rotational spectra of both species have been investigated at millimeter wavelengths. Vinyl mercaptan was produced in a radiofrequency discharge through a constant flow of ethanedithiol at low pressure. Both syn and anti rotamers were observed and new extensive sets of molecular parameters were obtained. Owing to its close structural relationship to vinyl alcohol and the astronomical abundance of complex sulfur-bearing molecules, vinyl mercaptan is a plausible candidate for future radio astronomical searches. M. Tanimoto et al. J. Mol. Spectrosc. 78, 95--105 & 106--119 (1979)

  1. Production of Catalyst-Free Hyperpolarised Ethanol Aqueous Solution via Heterogeneous Hydrogenation with Parahydrogen

    NASA Astrophysics Data System (ADS)

    Salnikov, Oleg G.; Kovtunov, Kirill V.; Koptyug, Igor V.

    2015-09-01

    An experimental approach for the production of catalyst-free hyperpolarised ethanol solution in water via heterogeneous hydrogenation of vinyl acetate with parahydrogen and the subsequent hydrolysis of ethyl acetate was demonstrated. For an efficient hydrogenation, liquid vinyl acetate was transferred to the gas phase by parahydrogen bubbling and almost completely converted to ethyl acetate with Rh/TiO2 catalyst. Subsequent dissolution of ethyl acetate gas in water containing OH- ions led to the formation of catalyst- and organic solvent-free hyperpolarised ethanol and sodium acetate. These results represent the first demonstration of catalyst- and organic solvent-free hyperpolarised ethanol production achieved by heterogeneous hydrogenation of vinyl acetate vapour with parahydrogen and the subsequent ethyl acetate hydrolysis.

  2. Production of Catalyst-Free Hyperpolarised Ethanol Aqueous Solution via Heterogeneous Hydrogenation with Parahydrogen.

    PubMed

    Salnikov, Oleg G; Kovtunov, Kirill V; Koptyug, Igor V

    2015-09-09

    An experimental approach for the production of catalyst-free hyperpolarised ethanol solution in water via heterogeneous hydrogenation of vinyl acetate with parahydrogen and the subsequent hydrolysis of ethyl acetate was demonstrated. For an efficient hydrogenation, liquid vinyl acetate was transferred to the gas phase by parahydrogen bubbling and almost completely converted to ethyl acetate with Rh/TiO2 catalyst. Subsequent dissolution of ethyl acetate gas in water containing OH(-) ions led to the formation of catalyst- and organic solvent-free hyperpolarised ethanol and sodium acetate. These results represent the first demonstration of catalyst- and organic solvent-free hyperpolarised ethanol production achieved by heterogeneous hydrogenation of vinyl acetate vapour with parahydrogen and the subsequent ethyl acetate hydrolysis.

  3. Covalent immobilization of metal organic frameworks onto chemical resistant poly(ether ether ketone) jacket for stir bar extraction.

    PubMed

    Wang, Chenlu; Zhou, Wei; Liao, Xiaoyan; Wang, Xuemei; Chen, Zilin

    2018-09-26

    Preparation of stir bar extraction (SBSE) device with high physical and chemical stability is important and challenging by date. A novel poly (ether ether ketone) (PEEK) tube with excellent mechanical property and chemical stability was firstly used as jacket of metal bar for preparation of stir bar. By employing covalent modification method, the inherent chemical resistant problem of PEEK which restricts the modification of sorbents was well solved. After functionalization, plenty of benzoic acid groups were formed onto the PEEK jacket. Metal organic frameworks of aluminium-based Materials of Institute Lavoisier-68 (MIL-68) was in situ immobilized onto the PEEK surface (MIL-68@PEEK) by the bonding with benzoic acid groups. Afterwards, a facile dumbbell-shaped structure was designed for reducing the friction between sorbents and bottom of container. Due to superior property of the PEEK jacket and the covalent modification method, the MIL-68 modified PEEK jacket SBSE device showed good robustness. After coupling with HPLC-MS/MS, the MIL-68@PEEK-based SBSE device was used to analyse of three parabens including methyl paraben, ethyl paraben and propyl paraben. The method had low limit detection up to 1 pg mL -1 with good linearity (R 2  ≥ 0.9978) and good reproducibility (relative standard deviation ≤ 9.74%). The method has been applied to the detection of parabens in cosmetics and rabbit plasma after painted with cosmetics with recoveries between 73.25% and 104.23%. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Transesterification of propylene glycol methyl ether in chromatographic reactors using anion exchange resin as a catalyst.

    PubMed

    Oh, Jungmin; Sreedhar, Balamurali; Donaldson, Megan E; Frank, Timothy C; Schultz, Alfred K; Bommarius, Andreas S; Kawajiri, Yoshiaki

    2016-09-30

    Reactive chromatography using an anion exchange resin is proposed for a transesterification reaction of propylene glycol methyl ether (DOWANOL™ PM) with ethyl acetate to produce propylene glycol methyl ether acetate (DOWANOL™ PMA). This reaction is studied in batch and chromatographic reactors catalyzed by an anion exchange resin. Several anion exchange resins are tested and compared based on the performance of resin as an adsorbent and a catalyst. A chromatographic column is packed with a selected catalyst, AMBERLITE™ IRA904, and both reaction and chromatographic elution are studied at different temperatures and feed concentrations. The resulting chromatograms are fitted to a mathematical model to obtain adsorption equilibrium and reaction kinetic parameters by the inverse method. Compared to esterification investigated in a previous study, transesterification has advantages such as a higher conversion at lower temperature and easy removal of the byproduct which may lead to higher productivity. Deactivation of anion exchange resins is observed and potential solutions are suggested. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. 21 CFR 177.1350 - Ethylene-vinyl acetate copolymers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene-vinyl acetate copolymers. 177.1350 Section... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1350 Ethylene-vinyl acetate copolymers. Ethylene-vinyl acetate copolymers may be safely used as articles or components of articles...

  6. 21 CFR 175.270 - Poly(vinyl fluoride) resins.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...(vinyl fluoride) basic resins have an intrinsic viscosity of not less than 0.75 deciliter per gram as determined by ASTM method D1243-79, “Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride... (ASTM method D1243-79, “Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers...

  7. 29 CFR 1915.1017 - Vinyl chloride.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Vinyl chloride. 1915.1017 Section 1915.1017 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... § 1915.1017 Vinyl chloride. Note: The requirements applicable to shipyard employment under this section...

  8. Thermal degradation and plasticizing mechanism of poly(vinyl chloride) plasticized with a novel cardanol derived plasticizer

    NASA Astrophysics Data System (ADS)

    Chen, J.; Nie, X. A.; Jiang, J. C.; Zhou, Y. H.

    2018-01-01

    A natural plasticizer cardanol derivatives glycidyl ether (CGE) was synthesized and employed as a plasticizer for the poly(vinyl chloride). The effect of CGE on thermal degradation of PVC films and its plasticizing mechanism were firstly reported. The molecular structure of CGE was characterized with Fourier transform infrared spectroscopy (FTIR). Thermal properties, degradation properties and compatibility of the PVC films were investigated by Differential scanning calorimeter analysis (DSC), Thermogravimetric analysis (TGA) and FTIR, respectively. Compared with the commercial plasticizers dioctylphthalate (DOP), CGE can endow PVC film with a decrease of 4.31 °C in glass transition temperature (Tg), an increase of 24.01 °C and 25.53 °C in 10% weight loss (T 10) and 50% weight loss (T 50) respectively, and a higher activetion energy of thermal degradation (Ea ).

  9. Physiologically based pharmacokinetic model for ethyl tertiary‐butyl ether and tertiary‐butyl alcohol in rats: Contribution of binding to α2u–globulin in male rats and high‐exposure nonlinear kinetics to toxicity and cancer outcomes

    PubMed Central

    Ring, Caroline; Banton, Marcy I.; Leavens, Teresa L.

    2016-01-01

    Abstract In cancer bioassays, inhalation, but not drinking water exposure to ethyl tertiary‐butyl ether (ETBE), caused liver tumors in male rats, while tertiary‐butyl alcohol (TBA), an ETBE metabolite, caused kidney tumors in male rats following exposure via drinking water. To understand the contribution of ETBE and TBA kinetics under varying exposure scenarios to these tumor responses, a physiologically based pharmacokinetic model was developed based on a previously published model for methyl tertiary‐butyl ether, a structurally similar chemical, and verified against the literature and study report data. The model included ETBE and TBA binding to the male rat‐specific protein α2u–globulin, which plays a role in the ETBE and TBA kidney response observed in male rats. Metabolism of ETBE and TBA was described as a single, saturable pathway in the liver. The model predicted similar kidney AUC0–∞ for TBA for various exposure scenarios from ETBE and TBA cancer bioassays, supporting a male‐rat‐specific mode of action for TBA‐induced kidney tumors. The model also predicted nonlinear kinetics at ETBE inhalation exposure concentrations above ~2000 ppm, based on blood AUC0–∞ for ETBE and TBA. The shift from linear to nonlinear kinetics at exposure concentrations below the concentration associated with liver tumors in rats (5000 ppm) suggests the mode of action for liver tumors operates under nonlinear kinetics following chronic exposure and is not relevant for assessing human risk. Copyright © 2016 The Authors Journal of Applied Toxicology Published by John Wiley & Sons Ltd PMID:27885692

  10. Poly(arylene ether)s That Resist Atomic Oxygen

    NASA Technical Reports Server (NTRS)

    Connell, John W.; Hergenrother, Paul; Smith, Joseph G., Jr.

    1994-01-01

    Novel poly(arylene ether)s containing phosphine oxide (PAEPO's) made via aromatic nucleophilic displacement reactions of activated aromatic dihalides (or, in some cases, activated aromatic dinitro compounds) with new bisphenol monomers containing phosphine oxide. Exhibited favorable combination of physical and mechanical properties and resistance to monatomic oxygen in oxygen plasma environment. Useful as adhesives, coatings, films, membranes, moldings, and composite matrices.

  11. Crown ethers in graphene

    DOE PAGES

    Guo, Junjie; Lee, Jaekwang; Contescu, Cristian I.; ...

    2014-11-13

    Crown ethers, introduced by Pedersen1, are at their most basic level neutral rings constructed of oxygen atoms linked by two- or three-carbon chains. They have attracted special attention for their ability to selectively incorporate various atoms2 or molecules within the cavity formed by the ring3-6. This property has led to the use of crown ethers and their compounds in a wide range of chemical and biological applications7,8. However, crown ethers are typically highly flexible, frustrating efforts to rigidify them for many uses that demand higher binding affinity and selectivity9,10. In this Letter, we report atomic-resolution images of the same basicmore » structures of the original crown ethers embedded in graphene. This arrangement constrains the crown ethers to be rigid and planar and thus uniquely suited for the many applications that crown ethers are known for. First-principles calculations show that the close similarity of the structures seen in graphene with those of crown ether molecules also extends to their selectivity towards specific metal cations depending on the ring size. Atoms (or molecules) incorporated within the crown ethers in graphene offer a simple environment that can be easily and systematically probed and modeled. Thus, we expect that this discovery will introduce a new wave of investigations and applications of chemically functionalized graphene.« less

  12. 40 CFR Table 4 to Subpart F of... - Organic Hazardous Air Pollutants Subject to Cooling Tower Monitoring Requirements in § 63.104

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Dichlorobenzidine (3,3″-) 91941 Dichloroethane (1,2-) (Ethylene dichloride) (EDC) 107062 Dichloroethyl ether (Bis(2... Ethyl acrylate 140885 Ethylbenzene 100414 Ethyl chloride (Chloroethane) 75003 Ethylene dibromide (Dibromoethane) 106934 Ethylene glycol dimethyl ether 110714 Ethylene glycol monobutyl ether 111762 Ethylene...

  13. Vinyl acetate

    Integrated Risk Information System (IRIS)

    Vinyl acetate ; CASRN 108 - 05 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  14. Vinyl chloride

    Integrated Risk Information System (IRIS)

    EPA / 635R - 00 / 004 TOXICOLOGICAL REVIEW OF VINYL CHLORIDE ( CAS No . 75 - 01 - 4 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) May 2000 U.S . Environmental Protection Agency Washington , DC DISCLAIMER This document has been reviewed in accordance w

  15. Vinyl bromide

    Integrated Risk Information System (IRIS)

    Vinyl bromide ; CASRN 593 - 60 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  16. Catalytic oxidation of dimethyl ether

    DOEpatents

    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.

  17. New polyarylene ethers

    NASA Technical Reports Server (NTRS)

    Hergenrother, P. M.; Havens, S. J.; Jensen, B. J.

    1986-01-01

    A series of new polyarylene ethers (PAEs) were prepared from the reaction of activated dihalo compounds with various bisphenols. Measured number average molecular weights for the PAEs ranged from 13,500 to 39,400 g/mole, and glass transition temperatures varied from 152 to 280 C. Ethynyl-terminated polyarylene ethers (ETPAEs) were also prepared by endcapping hydroxy-terminated polyarylene ethers with 4-ethynylbenzoyl chloride. Structure/property relationships for the PAEs, and the advantages offered by the ETPAEs, are discussed.

  18. 40 CFR 721.10595 - Octadecen-1-aminium, N-ethyl-N,N-dimethy-, ethyl sulfate (1:1).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-dimethy-, ethyl sulfate (1:1). 721.10595 Section 721.10595 Protection of Environment ENVIRONMENTAL...-, ethyl sulfate (1:1). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as octadecen-1-aminium, N-ethyl-N,N-dimethy-, ethyl sulfate (1:1) (PMN P-11...

  19. 40 CFR 721.10595 - Octadecen-1-aminium, N-ethyl-N,N-dimethy-, ethyl sulfate (1:1).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-dimethy-, ethyl sulfate (1:1). 721.10595 Section 721.10595 Protection of Environment ENVIRONMENTAL...-, ethyl sulfate (1:1). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as octadecen-1-aminium, N-ethyl-N,N-dimethy-, ethyl sulfate (1:1) (PMN P-11...

  20. IRIS Toxicological Review of Vinyl Chloride (Final Report ...

    EPA Pesticide Factsheets

    EPA is announcing the release of the final report, Toxicological Review of Vinyl Chloride: in support of the Integrated Risk Information System (IRIS). The updated Summary for Vinyl Chloride and accompanying Quickview have also been added to the IRIS Database. Common synonyms of vinyl chloride (VC) include chloroethene, chloroethylene, ethylene monochloride, and monochloroethene. VC is a synthetic chemical used as a chemical intermediate in the polymerization of polyvinyl chloride.

  1. 40 CFR 721.10262 - Oxime, Me vinyl silane (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Oxime, Me vinyl silane (generic). 721... Substances § 721.10262 Oxime, Me vinyl silane (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as oxime, Me vinyl silane (PMN P...

  2. 40 CFR 721.10262 - Oxime, Me vinyl silane (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Oxime, Me vinyl silane (generic). 721... Substances § 721.10262 Oxime, Me vinyl silane (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as oxime, Me vinyl silane (PMN P...

  3. 21 CFR 177.1960 - Vinyl chloride-hexene-1 copolymers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Vinyl chloride-hexene-1 copolymers. 177.1960... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1960 Vinyl chloride-hexene-1 copolymers. The vinyl chloride-hexene-1 copolymers identified in paragraph (a) of this section or as...

  4. 46 CFR 154.1740 - Vinyl chloride: Inhibiting and inerting.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Vinyl chloride: Inhibiting and inerting. 154.1740... Operating Requirements § 154.1740 Vinyl chloride: Inhibiting and inerting. When a vessel is carrying vinyl chloride, the master shall ensure that: (a) Section 154.1818 is met; or (b) Section 154.1710 is met, and...

  5. Viscometric investigation of compatibilization of the poly(vinyl chloride)/poly(ethylene-co-vinyl acetate) blends by terpolymer of maleic anhydride styrene vinyl acetate

    NASA Astrophysics Data System (ADS)

    İmren, Dilek; Boztuğ, Ali; Yılmaz, Ersen; Zengin, H. Bayram

    2008-11-01

    In this study, a blend of poly(vinyl chloride) (PVC)/ethylene-co-vinyl acetate (EVA) was compatibilized by terpolymer of maleic anhydride-styrene-vinyl acetate (MAStVA) used as a compatibilizer. It was prepared the blends of 50/50 PVC/EVA containing 2-10% of the terpolymer. The compatibility experiences of these blends were investigated by using viscometric method in the range of concentrations (0.5-2.0 g dL -1) where tetrahydrofuran (THF) is the solvent. The interaction parameter (Δ b) was used to study the miscibility and compatibility of polymer blend in solution, obtained from the modified Krigbaum and Wall theory. Turbidity and FTIR measurements were also used to investigate the miscibility of this pair of polymers. The values of the relative viscosities of the each polymer solution and their blends were measured by a Cannon-Fenske type viscometer. In consequence of the study, it was observed that a considerable improvement was achieved in the miscibility of PVC/EVA blends by adding among 5 and 10 wt% of compatibilizer.

  6. Physiologically based pharmacokinetic model for ethyl tertiary-butyl ether and tertiary-butyl alcohol in rats: Contribution of binding to α2u-globulin in male rats and high-exposure nonlinear kinetics to toxicity and cancer outcomes.

    PubMed

    Borghoff, Susan J; Ring, Caroline; Banton, Marcy I; Leavens, Teresa L

    2017-05-01

    In cancer bioassays, inhalation, but not drinking water exposure to ethyl tertiary-butyl ether (ETBE), caused liver tumors in male rats, while tertiary-butyl alcohol (TBA), an ETBE metabolite, caused kidney tumors in male rats following exposure via drinking water. To understand the contribution of ETBE and TBA kinetics under varying exposure scenarios to these tumor responses, a physiologically based pharmacokinetic model was developed based on a previously published model for methyl tertiary-butyl ether, a structurally similar chemical, and verified against the literature and study report data. The model included ETBE and TBA binding to the male rat-specific protein α2u-globulin, which plays a role in the ETBE and TBA kidney response observed in male rats. Metabolism of ETBE and TBA was described as a single, saturable pathway in the liver. The model predicted similar kidney AUC 0-∞ for TBA for various exposure scenarios from ETBE and TBA cancer bioassays, supporting a male-rat-specific mode of action for TBA-induced kidney tumors. The model also predicted nonlinear kinetics at ETBE inhalation exposure concentrations above ~2000 ppm, based on blood AUC 0-∞ for ETBE and TBA. The shift from linear to nonlinear kinetics at exposure concentrations below the concentration associated with liver tumors in rats (5000 ppm) suggests the mode of action for liver tumors operates under nonlinear kinetics following chronic exposure and is not relevant for assessing human risk. Copyright © 2016 The Authors Journal of Applied Toxicology Published by John Wiley & Sons Ltd. Copyright © 2016 The Authors Journal of Applied Toxicology Published by John Wiley & Sons Ltd.

  7. 27 CFR 21.59 - Formula No. 32.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ....Cellulose intermediates and industrial collodions. 052.Inks (not including meat branding inks). 241.... 523.Other ethyl esters. 561.Ethyl ether. 562.Other ethers. 571.Ethylene dibromide. 572.Ethylene gas...

  8. Propenyl ether monomers for photopolymerization

    DOEpatents

    Crivello, J.V.

    1996-10-22

    Propenyl ether monomers of formula A(OCH{double_bond}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 the above formula 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.

  9. Propenyl ether monomers for photopolymerization

    DOEpatents

    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.

  10. Copper/amino acid catalyzed cross-couplings of aryl and vinyl halides with nucleophiles.

    PubMed

    Ma, Dawei; Cai, Qian

    2008-11-18

    Copper-assisted Ullmann-type coupling reactions are valuable transformations for organic synthesis. Researchers have extensively applied these reactions in both academic and industrial settings. However, two important issues, the high reaction temperatures (normally above 150 degrees C) and the stoichiometric amounts of copper necessary, have greatly limited the reaction scope. To solve these problems, we and other groups have recently explored the use of special ligands to promote these coupling reactions. We first showed that the structure of alpha-amino acids can accelerate Cu-assisted Ullmann reactions, leading to the coupling reactions of aryl halides and alpha-amino acids at 80-90 degrees C. In response to these encouraging results, we also discovered that an l-proline ligand facilitated the following transformations: (1) coupling of aryl halides with primary amines, cyclic secondary amines, and N-containing heterocycles at 40-90 degrees C; (2) coupling of aryl halides with sulfinic acid salts at 80-95 degrees C; (3) azidation of aryl halides and vinyl halides with sodium azide at 40-95 degrees C; (4) coupling of aryl halides with activated methylene compounds at 25-50 degrees C. In addition, we found that N,N-dimethylglycine as a ligand facilitated Cu-catalyzed biaryl ether formation at 90 degrees C. Moreover, Sonogashira reactions worked in the absence of palladium and phosphine ligands, forming enamides from vinyl halides and amides at temperatures ranging from ambient temperature up to 80 degrees C. Furthermore, we discovered that an ortho-amide group can accelerate some Ullmann-type reactions. This functional group in combination with other ligand effects allowed for aryl amination or biaryl ether formation at ambient temperature. The coupling between aryl halides and activated methylene compounds even proceeded at -45 degrees C to enantioselectively form a quaternary carbon center. Taking advantage of these results, we developed several novel approaches

  11. 3D-Quantitative structure-activity relationships of synthetic antileishmanial ring-substituted ether phospholipids.

    PubMed

    Kapou, Agnes; Benetis, Nikolas P; Avlonitis, Nikos; Calogeropoulou, Theodora; Koufaki, Maria; Scoulica, Efi; Nikolaropoulos, Sotiris S; Mavromoustakos, Thomas

    2007-02-01

    The application of 2D-NMR spectroscopy and Molecular Modeling in determining the active conformation of flexible molecules in 3D-QSAR was demonstrated in the present study. In particular, a series of 33 flexible synthetic phospholipids, either 2-(4-alkylidene-cyclohexyloxy)ethyl- or omega-cycloalkylidene-substituted ether phospholipids were systematically evaluated for their in vitro antileishmanial activity against the promastigote forms of Leishmania infantum and Leishmania donovani by CoMFA and CoMSIA 3D-QSAR studies. Steric and hydrophobic properties of the phospholipids under study appear to govern their antileishmanial activity against both strains, while the electrostatic properties have no significant contribution. The acknowledgment of these important properties of the pharmacophore will aid in the rational design of new analogues with higher activity.

  12. 46 CFR 154.1750 - Butadiene or vinyl chloride: Refrigeration system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Butadiene or vinyl chloride: Refrigeration system. 154... and Operating Requirements § 154.1750 Butadiene or vinyl chloride: Refrigeration system. A refrigeration system for butadiene or vinyl chloride must not use vapor compression unless it: (a) Avoids any...

  13. 46 CFR 154.1750 - Butadiene or vinyl chloride: Refrigeration system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Butadiene or vinyl chloride: Refrigeration system. 154... and Operating Requirements § 154.1750 Butadiene or vinyl chloride: Refrigeration system. A refrigeration system for butadiene or vinyl chloride must not use vapor compression unless it: (a) Avoids any...

  14. 46 CFR 154.1750 - Butadiene or vinyl chloride: Refrigeration system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Butadiene or vinyl chloride: Refrigeration system. 154... and Operating Requirements § 154.1750 Butadiene or vinyl chloride: Refrigeration system. A refrigeration system for butadiene or vinyl chloride must not use vapor compression unless it: (a) Avoids any...

  15. 46 CFR 154.1750 - Butadiene or vinyl chloride: Refrigeration system.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Butadiene or vinyl chloride: Refrigeration system. 154... and Operating Requirements § 154.1750 Butadiene or vinyl chloride: Refrigeration system. A refrigeration system for butadiene or vinyl chloride must not use vapor compression unless it: (a) Avoids any...

  16. 46 CFR 154.1750 - Butadiene or vinyl chloride: Refrigeration system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Butadiene or vinyl chloride: Refrigeration system. 154... and Operating Requirements § 154.1750 Butadiene or vinyl chloride: Refrigeration system. A refrigeration system for butadiene or vinyl chloride must not use vapor compression unless it: (a) Avoids any...

  17. In vitro antioxidant activity of pet ether extract of black pepper

    PubMed Central

    Singh, Ramnik; Singh, Narinder; Saini, B.S.; Rao, Harwinder Singh

    2008-01-01

    Objective: To investigate the in vitro antioxidant activity of different fractions (R1, R2 and R3) obtained from pet ether extract of black pepper fruits (Piper nigrum Linn.) Materials and Methods: The fractions R1, R2 and R3 were eluted from pet ether and ethyl acetate in the ratio of 6:4, 5:5 and 4:6, respectively. 1,1-Diphenyl-2-picryl-hydrazyl (DPPH) radical, superoxide anion radical, nitric oxide radical, and hydroxyl radical scavenging assays were carried out to evaluate the antioxidant potential of the extract. Results: The free radical scavenging activity of the different fractions of pet ether extract of P. nigrum (PEPN) increased in a concentration dependent manner. The R3 and R2 fraction of PEPN in 500 µg/ml inhibited the peroxidation of a linoleic acid emulsion by 60.48±3.33% and 58.89±2.51%, respectively. In DPPH free radical scavenging assay, the activity of R3 and R2 were found to be almost similar. The R3 (100µg/ml) fraction of PEPN inhibited 55.68±4.48% nitric oxide radicals generated from sodium nitroprusside, whereas curcumin in the same concentration inhibited 84.27±4.12%. Moreover, PEPN scavenged the superoxide radical generated by the Xanthine/Xanthine oxidase system. The fraction R2 and R3 in the doses of 1000µg/ml inhibited 61.04±5.11% and 63.56±4.17%, respectively. The hydroxyl radical was generated by Fenton's reaction. The amounts of total phenolic compounds were determined and 56.98 µg pyrocatechol phenol equivalents were detected in one mg of R3. Conclusions: P. nigrum could be considered as a potential source of natural antioxidant. PMID:20040947

  18. Multi-stage Mass Spectrometry of Poly(vinyl pyrrolidone) and Its Vinyl Succinimide Copolymer Formed upon Exposure to Sodium Hypochlorite

    PubMed Central

    Fouquet, Thierry; Torimura, Masaki; Sato, Hiroaki

    2016-01-01

    The degradation routes of poly(vinyl pyrrolidone) (PVP) exposed to sodium hypochlorite (bleach) have been previously investigated using chemical analyses such as infrared spectroscopy. So far, no reports have proposed mass spectrometry (MS) as an alternative tool despite its capability to provide molecular and structural information using its single stage electrospray (ESI) or matrix assisted laser desorption ionization (MALDI) and multi stage (MSn) configurations, respectively. The present study thus reports on the characterization of PVP after its exposure to bleach by high resolution MALDI spiralTOF-MS and Kendrick mass defect analysis providing clues as to the formation of a vinyl pyrrolidone/vinyl succinimide copolymeric degradation product. A thorough investigation of the fragmentation pathways of PVP adducted with sodium and proton allows one main route to be described—namely the release of the pyrrolidone pendant group in a charge remote and charge driven mechanism, respectively. Extrapolating this fragmentation pathway, the oxidation of vinyl pyrrolidone into vinyl succinimide hypothesized from the single stage MS is validated by the detection of an alternative succinimide neutral loss in lieu of the pyrrolidone release in the ESI-MSn spectra of the aged PVP sample. It constitutes an example of application of multi-stage mass spectrometry for the characterization of the degradation of polymeric samples at a molecular level. PMID:27800293

  19. Responses of the L51781Y tk/sup +//tk/sup -/ mouse lymphoma cell forward mutation assay: III. 72 coded chemicals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McGregor, D.B.; Brown, A.; Cattanach, P.

    Seventy-two chemicals were tested for their mutagenic potential in the L51781Y tk/sup +///sup -/ mouse lymphoma cell forward mutation assay, using procedures based upon those described previously. Cultures were exposed to the chemicals for 4 hr, then cultured for 2 days before planting in soft agar with or without trifluorothymidine (TFT), 3 ..mu..g/ml. The chemicals were tested at least twice. Significant responses were obtained with allyl isothiocyanate, p-benzoquinone dioxime, benzyl acetate, 2-biphenylamine HCl, bis(2-chloro-1-methylethyl)ether, cadmium chloride, chlordane, chlorobenzene, chlorobenzilate, 2-chloroethanol, chlorothalonil, cytarabine x HCl, p,p'-DDE, diazinon, 2,6-dichloro-p-phenylenediamine, N,N-diethylthiourea, diglycidylresorcinol ether, 2,4-dimethoxy aniline x HCl, disperse yellow 3, endosulfan, 1,2-epoxyhexadecane, ethylmore » acrylate, ethyl benzene, ethylene thiourea, F D and C yellow Number 6, furan, heptachlor, isophorone, mercuric chloride, 4,4'-methylenedianiline x 2 HCl, methyl viologen, nickel sulfate x 6H/sub 2/O, 4,4'-oxydianiline, pentachloroethane, piperonyl butoxide, propyl gallate, quinoline, rotenone, 2,4,5,6-tetrachloro-4-nitro-anisole, 1,1,1,2-tetrachloroethane, trichlorfon, 2,4,6-trichlorophenol, 2,4,5-trimethoxybenzaldehyde, 1,1,3-trimethyl-2-thiourea, 1-vinyl-3-cyclopetene dioxide, vinyl toluene, and ziram. The assay was incapable of providing a clear indication of whether some chemicals were mutagens; these benzyl alcohol, 1,4-dichlorobenzene, phenol, succinic acid-2,2-dimethyl hydrazide, and toluene.« less

  20. Degradable vinyl polymers for biomedical applications.

    PubMed

    Delplace, Vianney; Nicolas, Julien

    2015-10-01

    Vinyl polymers have been the focus of intensive research over the past few decades and are attractive materials owing to their ease of synthesis and their broad diversity of architectures, compositions and functionalities. Their carbon-carbon backbones are extremely resistant to degradation, however, and this property limits their uses. Degradable polymers are an important field of research in polymer science and have been used in a wide range of applications spanning from (nano)medicine to microelectronics and environmental protection. The development of synthetic strategies to enable complete or partial degradation of vinyl polymers is, therefore, of great importance because it will offer new opportunities for the application of these materials. This Review captures the most recent and promising approaches to the design of degradable vinyl polymers and discusses the potential of these materials for biomedical applications.

  1. Some actions of substituted choline phenyl ethers, particularly of choline 2:6-xylyl ether

    PubMed Central

    Edge, N. D.; Mason, D. F. J.; Wyllie, J. H.

    1957-01-01

    Marked nicotine-like stimulant properties are possessed by choline phenyl ether and choline o-tolyl ether, and to a decreasing extent by choline 2:6-xylyl ether and choline 2:4:6-mesityl ether. The compounds all show neuromuscular blocking properties, which are of short duration and pass from mainly decamethonium-like to mainly curare-like as more methyl groups are added to the phenyl nucleus. This series of compounds also possesses muscarinic, weak anti-adrenaline and vasodilator properties, as well as long-lasting local anaesthetic effects in the two compounds tested by intradermal injection. PMID:13460236

  2. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    Phillips Petroleum Co. is poised to license its high conversion process to produce fuel ethers for blending in reformulated gasolines. The technology has been proven in a Phillips semiworks at Bartlesville, Okla. The process can produce methyl tertiary butyl ether, ethyl tertiary butyl ether, tertiary amyl methyl ether, or tertiary amyl ethyl ether with typical refinery process equipment and techniques. Phillips said it can achieve conversion levels of 92-99%, depending on the ether. The ether produced is determined by which hydrocarbon fraction is used for feedstock and which alcohol is chosen for reaction. The process is described.

  3. Surveillance for angiosarcoma of the liver among vinyl chloride workers.

    PubMed

    Collins, James J; Jammer, Brenda; Sladeczek, Frank M; Bodnar, Catherine M; Salomon, Sergio S

    2014-11-01

    We report the results of our angiosarcoma of the liver (ASL) registry to assess the occurrence, the impact of exposures to vinyl chloride, and to quantify latency. We examined more than 73,000 death certificates of North American workers employed between 1940 and 2008. We found 13 deaths of ASL among workers with vinyl chloride exposure. All 13 occurred at single plant among workers with high vinyl chloride exposure. The mean latency after first exposure was 36.5 years ranging from 24 to 56 years. No ASL deaths occurred among workers with vinyl chloride exposures after 1974, when exposures were reduced. We may have seen the last case of ASL among workers exposed to vinyl chloride. Nevertheless, given the long latency of this cancer, continued surveillance seems prudent.

  4. Development and Characterization of Poly(1-vinylpyrrolidone-co-vinyl acetate) Copolymer Based Polymer Electrolytes

    PubMed Central

    Sa'adun, Nurul Nadiah; Subramaniam, Ramesh; Kasi, Ramesh

    2014-01-01

    Gel polymer electrolytes (GPEs) are developed using poly(1-vinylpyrrolidone-co-vinyl acetate) [P(VP-co-VAc)] as the host polymer, lithium bis(trifluoromethane) sulfonimide [LiTFSI] as the lithium salt and ionic liquid, and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide [EMImTFSI] by using solution casting technique. The effect of ionic liquid on ionic conductivity is studied and the optimum ionic conductivity at room temperature is found to be 2.14 × 10−6 S cm−1 for sample containing 25 wt% of EMImTFSI. The temperature dependence of ionic conductivity from 303 K to 353 K exhibits Arrhenius plot behaviour. The thermal stability of the polymer electrolyte system is studied by using thermogravimetric analysis (TGA) while the structural and morphological properties of the polymer electrolyte is studied by using Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction analysis (XRD), respectively. PMID:25431781

  5. Synthesis of carboxylic acids, esters, alcohols and ethers containing a tetrahydropyran ring derived from 6-methyl-5-hepten-2-one.

    PubMed

    Hanzawa, Yohko; Hashimoto, Kahoko; Kasashima, Yoshio; Takahashi, Yoshiko; Mino, Takashi; Sakamoto, Masami; Fujita, Tsutomu

    2012-01-01

    3-hydroxy acids, 3-hydroxy-3,7-dimethyloct-6-enoic acid (1) and 3-hydroxy-2,2,3,7-tetramethyloct-6-enoic acid (2), were prepared from 6-methyl-5-hepten-2-one, and they were subsequently used to prepare (2,6,6-trimethyltetrahydropyran-2-yl)acetic acid (3) and 2-methyl-2-(2,6,6-trimethyltetrahydropyran-2-yl)propanoic acid (4), respectively, via cyclization with an acidic catalyst such as boron trifluoride diethyl etherate or iodine. The reaction of carboxylic acids 3 and 4 with alcohols, including methanol, ethanol, and 1-propanol, produced the corresponding methyl, ethyl, and propyl esters, which all contained a tetrahydropyran ring. Reduction of carboxylic acids 3 and 4 afforded the corresponding alcohols. Subsequent reactions of these alcohols with several acyl chlorides produced novel esters. The alcohols also reacted with methyl iodide and sodium hydride to provide novel ethers. A one-pot cyclization-esterification of 1 to produce esters containing a tetrahydropyran ring, using iodine as a catalyst, was also investigated.

  6. Space, Time, Ether, and Kant

    NASA Astrophysics Data System (ADS)

    Wong, Wing-Chun Godwin

    This dissertation focused on Kant's conception of physical matter in the Opus postumum. In this work, Kant postulates the existence of an ether which fills the whole of space and time with its moving forces. Kant's arguments for the existence of an ether in the so-called Ubergang have been acutely criticized by commentators. Guyer, for instance, thinks that Kant pushes the technique of transcendental deduction too far in trying to deduce the empirical ether. In defense of Kant, I held that it is not the actual existence of the empirical ether, but the concept of the ether as a space-time filler that is subject to a transcendental deduction. I suggested that Kant is doing three things in the Ubergang: First, he deduces the pure concept of a space-time filler as a conceptual hybrid of the transcendental object and permanent substance to replace the category of substance in the Critique. Then he tries to prove the existence of such a space-time filler as a reworking of the First Analogy. Finally, he takes into consideration the empirical determinations of the ether by adding the concept of moving forces to the space -time filler. In reconstructing Kant's proofs, I pointed out that Kant is absolutely committed to the impossibility of action-at-a-distance. If we add this new principle of no-action-at-a-distance to the Third Analogy, the existence of a space-time filler follows. I argued with textual evidence that Kant's conception of ether satisfies the basic structure of a field: (1) the ether is a material continuum; (2) a physical quantity is definable on each point in the continuum; and (3) the ether provides a medium to support the continuous transmission of action. The thrust of Kant's conception of ether is to provide a holistic ontology for the transition to physics, which can best be understood from a field-theoretical point of view. This is the main thesis I attempted to establish in this dissertation.

  7. 40 CFR Table 2 to Subpart Ggg of... - Partially Soluble HAP

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Trichloroethylene Chloroethane (ethyl chloride) Trimethylpentane Vinyl acetate Xylene (p) Vinyl chloride N-hexane... Methylene chloride Allyl chloride N,N-dimethylaniline Benzene Propionaldehyde Benzyl chloride Propylene...

  8. 40 CFR Table 2 to Subpart Ggg of... - Partially Soluble HAP

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Trichloroethylene Chloroethane (ethyl chloride) Trimethylpentane Vinyl acetate Xylene (p) Vinyl chloride N-hexane... Methylene chloride Allyl chloride N,N-dimethylaniline Benzene Propionaldehyde Benzyl chloride Propylene...

  9. 40 CFR Table 2 to Subpart Ggg of... - Partially Soluble HAP

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Trichloroethylene Chloroethane (ethyl chloride) Trimethylpentane Vinyl acetate Xylene (p) Vinyl chloride N-hexane... Methylene chloride Allyl chloride N,N-dimethylaniline Benzene Propionaldehyde Benzyl chloride Propylene...

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

    NASA Astrophysics Data System (ADS)

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

    1993-04-01

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

  11. Anaerobic mineralization of vinyl chloride in Fe(III)-reducing, aquifer sediments

    USGS Publications Warehouse

    Bradley, P.M.; Chapelle, F.H.

    1996-01-01

    Within anaerobic aquifer systems, reductive dehalogenation of polychlorinated ethenes commonly results in the accumulation of vinyl chloride, which is highly toxic and carcinogenic to humans. Anaerobic reduction of vinyl chloride is considered to be slow and incomplete. Here, we provide the first evidence for anaerobic oxidation of vinyl chloride under Fe(III)reducing conditions. Addition of chelated Fe(III) (as Fe-EDTA) to anaerobic aquifer microcosms resulted in mineralization of up to 34% of [1,2- 14C]vinyl chloride within 84 h. The results indicate that vinyl chloride can be mineralized under anaerobic, Fe(III)-reducing conditions and that the bioavailability of Fe(III) is an important factor affecting the rates of mineralization.

  12. Production of methyl-vinyl ketone from levulinic acid

    DOEpatents

    Dumesic, James A [Verona, WI; West,; Ryan, M [Madison, WI

    2011-06-14

    A method for converting levulinic acid to methyl vinyl ketone is described. The method includes the steps of reacting an aqueous solution of levulinic acid, over an acid catalyst, at a temperature of from room temperature to about 1100 K. Methyl vinyl ketone is thereby formed.

  13. New Reactive Diluents for an Environmentally Efficient Approach to Composite Repair

    DTIC Science & Technology

    2010-02-16

    7.25 ppm, δ 77.0 ppm; MeOH-δ4, d 3.31 ppm, δ 49.15 ppm. The n-BuLi (2.5 M in hexanes), 4,4’-dibromophenyl ether, vinyl tributyltin , THF (anhydrous...4’-tributylsilyldiphenyl ether (34.48 g, 79 mmol), CsF, (25.28 g, 166 mmol), vinyl tributyltin (27.65 g, 87 mmol), Pd2(dba)3 (3.63 g, 4.0 mmol), and

  14. Far-Infrared Spectroscopy of Syn-Vinyl Alcohol

    NASA Astrophysics Data System (ADS)

    Raston, Paul; Bunn, Hayley

    2016-06-01

    Vinyl alcohol has been extensively studied in both the microwave and mid-IR spectral regions, where 9 out of 15 vibrational modes have been identified. Here we present the first far-IR spectrum of vinyl alcohol, collected below 700 wn at the Australian Synchrotron. The high resolution (0.001 wn) spectrum reveals the νb{11} and νb{15} fundamentals of syn-vinyl alcohol at 489 wn and 407 wn, in addition to two hot bands of the νb{15} mode at 369 wn and 323 wn. High J transitions in the R-branch of the νb{15} band were found to be perturbed by an a-axis Coriolis interaction with the nearby νb{11} state. The νb{15} torsional mode of syn-vinyl alcohol was fit using a Watson's A-reduced Hamiltonian to yield rotational, centrifugal distortion, and Coriolis coupling parameters. S. Saito, Chem. Phys. Lett. 42, 3 (1976) M. Rodler et al., J. Am. Chem. Soc. 106, 4029 (1948) Y. Koga et al., J. Mol. Spec. 145, 315 (1991) D-L. Joo et al., J. Mol. Spec. 197, 68 (1999)

  15. 49 CFR 173.322 - Ethyl chloride.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Ethyl chloride. 173.322 Section 173.322 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... SHIPMENTS AND PACKAGINGS Gases; Preparation and Packaging § 173.322 Ethyl chloride. Ethyl chloride must be...

  16. Human cytochrome P450 isozymes in metabolism and health effects of gasoline ethers.

    PubMed

    Hong, J Y; Wang, Y Y; Mohr, S N; Bondoc, F Y; Deng, C

    2001-05-01

    To reduce the production of carbon monoxide and other pollutants in motor vehicle exhaust, methyl tert-butyl ether (MTBE*), ethyl tert-butyl ether (ETBE), and tert-amyl methyl ether (TAME) are added to gasoline as oxygenates for more complete combustion. Among them, MTBE is the most widely used. The possible adverse effect of MTBE in humans is a public concern, but the human enzymes responsible for metabolism of these gasoline ethers and the causes or factors for increased sensitivity to MTBE in certain individuals are totally unknown. This information is important to understanding the health effects of MTBE in humans and to assessing the human relevance of pharmacokinetics and toxicity data obtained from animals. In the present study, we demonstrated that human liver is active in metabolizing MTBE to tert-butyl alcohol (TBA), a major circulating metabolite and an exposure marker of MTBE. The activity is localized in the microsomal fraction but not in the cytosol. Formation of TBA in human liver microsomes is NADPH-dependent and is significantly inhibited by carbon monoxide, which inhibits cytochrome P450 (CYP) enzymes. These results provide strong evidence that CYP enzymes play a critical role in the metabolism of MTBE in human livers. Human liver is also active in the oxidative metabolism of 2 other gasoline ethers, ETBE and TAME. We observed a large interindividual variation in metabolizing these gasoline ethers in 15 microsomal samples prepared from normal human livers. The activity level (pmol metabolite/min/mg) ranged from 204 to 2,890 for MTBE; 179 to 3,134 for ETBE; and 271 to 8,532 for TAME. The microsomal activities in metabolizing MTBE, ETBE, and TAME correlated highly with each other (r = 0.91 to 0.96), suggesting that these ethers are metabolized by the same enzyme(s). Correlation analysis of the ether-metabolizing activities with individual CYP enzyme activities in the human liver microsomes showed that the highest degree of correlation was with CYP

  17. Conformations and Barriers to Methyl Group Internal Rotation in Two Asymmetric Ethers: Propyl Methyl Ether and Butyl Methyl Ether

    NASA Astrophysics Data System (ADS)

    Long, B. E.; Dechirico, F.; Cooke, S. A.

    2012-06-01

    The conformational preferences of the O-C-C-C unit are important in many biological systems with the unit generally preferring a gauche configuration compared to an anti configuration. Butyl methyl ether and propyl methyl ether provide very simple systems for this phenomenom to manifest. Pure rotational spectra of the title molecules have been recorded using chirped pulse Fourier transform microwave spectroscopy (CP-FTMW). In the case of butyl methyl ether, only one conformer has been observed. This conformer has torsional angles of COCC = 180°, OCCC = 62° and CCCC = 180° (anti-gauche-anti) and rotational constants of A = 10259.4591(33) MHz, B = 1445.6470(13) MHz, and C = 1356.2944(14) MHz. The rotational spectrum was doubled and has been analyzed to produce an effective barrier to methyl group internal rotation of 780(35) cm-1. A prior rotational spectroscopic study on propyl methyl ether had focused only on the high energy anti-anti conformer. We have analyzed spectra from the lowest energy anti-gauche conformer and the spectroscopic constants will be presented. A summary of the differences in conformational energies and methyl group internal rotation barriers for the class of aliphatic asymmetric ethers will be presented. K. N. Houk, J. E. Eksterowicz, Y.-D. Wu, C. D. Fuglesang, D. B. Mitchell. J. Am. Chem. Soc. 115 (4170), 1993. Hiroshi Kato, Jun Nakagawa, Michiro Hayashi. J. Mol. Spectrosc. 80 (272), 1980.

  18. Persubstituted p-benzoquinone monoxime alkyl ethers and their molecular structure

    NASA Astrophysics Data System (ADS)

    Slaschinin, D. G.; Alemasov, Y. A.; Ilushkin, D. I.; Sokolenko, W. A.; Tovbis, M. S.; Kirik, S. D.

    2012-05-01

    Theoretical and experimental approaches were applied for the investigation of the reactivity of persubstituted 4-nitrosophenols in the reaction with alkyl iodides, in particular the potassium salt of 2,6-di(alkoxycarbonyl)-3,5-dimethyl-4-nitrosophenol. Hartre-Fock calculations showed that the anion negative charge was located mostly on the oxygen of hydroxyl group, while estimation of the total energy of the alkylated products pointed out the benefit of alkylation on the oxygen atom of the nitroso group yielding p-benzoquinone monoxime alkyl ethers. Methylation and ethylation of persubstituted nitrosophenols were carried out. The products obtained were investigated using X-ray diffraction, 1Н NMR spectroscopy and mass spectrometry. The crystal structure of the methyl ether of 2,6-di(alkoxycarbonyl)-3,5-dimethyl-1,4-benzoquinone-1-oxime (С15H19NO6) (I) was determined by the X-ray powder diffraction technique. The unit cell parameters were: a = 7.3322(6) Å, b = 10.5039(12) Å, c = 21.1520(20) Å, β = 93.742(6)°, V = 1625.58(2) Å3Z = 4, Sp.Gr. P21/c. The structure modeling was made in direct space by the Monte-Carlo approach using rigid and soft restrictions. The structure refinement was completed by the Rietveld method. It was established that the alkylation occurred on the oxygen atom of the nitroso group. The molecules (I) in the crystal structure were packed in columns along the axis a with pairwise convergence in a column up to the distance of 3.63 Å due to a 180° turn of every second molecule around the column axis. In the molecular structure the methyloxime group was oriented in the benzene plane and had π-conjugation with the ring. The ethoxycarbonyl groups were turned nearly perpendicular to the ring. Other compounds obtained had the structure of the alkyl ethers of 1.4-benzoquinone-1-oxime, which was proved by 1Н NMR spectroscopy and mass-spectrometry.

  19. 46 CFR 151.50-34 - Vinyl chloride (vinyl chloride monomer).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... be used as a “check” on the required closed gauge, nor as a means or sampling. (h) The words “CANCER... legend: cancer—suspect agent in this area protective equipment required authorized personnel only must be... clean and dry for each use, to prevent skin contact with liquid vinyl chloride. [CGFR 70-10, 35 FR 3714...

  20. 46 CFR 151.50-34 - Vinyl chloride (vinyl chloride monomer).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... be used as a “check” on the required closed gauge, nor as a means or sampling. (h) The words “CANCER... legend: cancer—suspect agent in this area protective equipment required authorized personnel only must be... clean and dry for each use, to prevent skin contact with liquid vinyl chloride. [CGFR 70-10, 35 FR 3714...

  1. 46 CFR 151.50-34 - Vinyl chloride (vinyl chloride monomer).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... be used as a “check” on the required closed gauge, nor as a means or sampling. (h) The words “CANCER... legend: cancer—suspect agent in this area protective equipment required authorized personnel only must be... clean and dry for each use, to prevent skin contact with liquid vinyl chloride. [CGFR 70-10, 35 FR 3714...

  2. Kinetic Analysis for the Multistep Profiles of Organic Reactions: Significance of the Conformational Entropy on the Rate Constants of the Claisen Rearrangement.

    PubMed

    Sumiya, Yosuke; Nagahata, Yutaka; Komatsuzaki, Tamiki; Taketsugu, Tetsuya; Maeda, Satoshi

    2015-12-03

    The significance of kinetic analysis as a tool for understanding the reactivity and selectivity of organic reactions has recently been recognized. However, conventional simulation approaches that solve rate equations numerically are not amenable to multistep reaction profiles consisting of fast and slow elementary steps. Herein, we present an efficient and robust approach for evaluating the overall rate constants of multistep reactions via the recursive contraction of the rate equations to give the overall rate constants for the products and byproducts. This new method was applied to the Claisen rearrangement of allyl vinyl ether, as well as a substituted allyl vinyl ether. Notably, the profiles of these reactions contained 23 and 84 local minima, and 66 and 278 transition states, respectively. The overall rate constant for the Claisen rearrangement of allyl vinyl ether was consistent with the experimental value. The selectivity of the Claisen rearrangement reaction has also been assessed using a substituted allyl vinyl ether. The results of this study showed that the conformational entropy in these flexible chain molecules had a substantial impact on the overall rate constants. This new method could therefore be used to estimate the overall rate constants of various other organic reactions involving flexible molecules.

  3. Responsive copolymers for enhanced petroleum recovery. Quarterly technical progress report, June 23--September 21, 1994

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McCormick, C.; Hester, R.

    Summaries are given on the technical progress on three tasks of this project. Monomer and polymer synthesis discusses the preparation of 1(7-aminoheptyloxymethyl)naphthalene and poly(maleic anhydride-alt-ethyl vinyl ether). Task 2, Characterization of molecular structure, discusses terpolymer solution preparation, UV analysis, fluorescence analysis, low angle laser light scattering, and viscometry. The paper discusses the effects of hydrophobic groups, the effect of pH, the effect of electrolyte addition, and photophysical studies. Task 3, Solution properties, describes the factorial experimental design for characterizing polymer solutions by light scattering, the light scattering test model, orthogonal factorial test design, linear regression in coded space, confidence levelmore » for coded space test mode coefficients, coefficients of the real space test model, and surface analysis of the model equations.« less

  4. A New Microfluidic Polymer Chip with an Embedded Cationic Surfactant Ion-selective Optode as a Detector for the Determination of Cationic Surfactants.

    PubMed

    Ashagre, Mekonnen Abiyot; Masadome, Takashi

    2018-01-01

    A new microfluidic polymer chip with an embedded cationic surfactant (CS) ion-selective optode (CS-optode) as a detector of flow-injection analysis (FIA) for the determination of CSs was developed. The optode sensing membrane is based on a poly(vinyl chloride) membrane plasticized with 2-nitrophenyl octyl ether containing tetrabromophenolphthalein ethyl ester. Under the optimal flow conditions of the FIA system, the CS-optode showed a good linear relationship between the peak heights in the absorbance, and the concentrations of CS in a concentration range from 50 to 400 μmol dm -3 . The sample throughput of the present system for the determination of a CS ion (300 μmol dm -3 zephiramine) was ca. 11 samples h -1 . The proposed FIA system was applied to determine the level of CS in dental rinses.

  5. Activation of C-O and C-C bonds and formation of novel HAlOH-ether complexes: an EPR study of the reaction of ground-state Al atoms with methylethyl ether and diethyl ether.

    PubMed

    Brunet, François D; Feola, Julie C; Joly, Helen A

    2012-03-15

    Reaction mixtures, containing Al atoms and methylethyl ether (MEE) or diethyl ether (DEE) in an adamantane matrix, were prepared with the aid of a metal-atom reactor known as a rotating cryostat. The EPR spectra of the resulting products were recorded from 77-260 K, at 10 K intervals. Al atoms were found to insert into methyl-O, ethyl-O, and C-C bonds to form CH(3)AlOCH(2)CH(3), CH(3)OAlCH(2)CH(3), and CH(3)OCH(2)AlCH(3), respectively, in the case of MEE while DEE produced CH(3)CH(2)AlOCH(2)CH(3) and CH(3)AlCH(2)OCH(2)CH(3), respectively. From the intensity of the transition lines attributed to the Al atom C-O insertion products of MEE, insertion into the methyl-O bond is preferred. The Al hyperfine interaction (hfi) extracted from the EPR spectra of the C-O insertion products was greater than that of the C-C insertion products, that is, 5.4% greater for the DEE system and 7% greater for the MEE system. The increase in Al hfi is thought to arise from the increased electron-withdrawing ability of the substituents bonded to Al. Besides HAlOH, resulting from the reaction of Al atoms with adventitious water, novel mixed HAlOH:MEE and HAlOH:DEE complexes were identified with the aid of isotopic studies involving H(2)(17)O and D(2)O. The Al and H hfi of HAlOH were found to decrease upon complex formation. These findings are consistent with the nuclear hfi calculated using a density functional theory (DFT) method with close agreement between theory and experiment occurring at the B3LYP level using a 6-311+G(2df,p) basis set.

  6. 21 CFR 184.1293 - Ethyl alcohol.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethyl alcohol. 184.1293 Section 184.1293 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1293 Ethyl alcohol. (a) Ethyl alcohol (ethanol) is the chemical C2H5OH. (b...

  7. 21 CFR 184.1293 - Ethyl alcohol.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ethyl alcohol. 184.1293 Section 184.1293 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1293 Ethyl alcohol. (a) Ethyl alcohol (ethanol) is the chemical C2H5OH. (b...

  8. Friction-induced surface activity of some hydrocarbons with clean and oxide-covered iron

    NASA Technical Reports Server (NTRS)

    Buckley, D. H.

    1973-01-01

    Sliding friction studies were conducted on a clean and oxide-covered iron surface with exposure of that surface to various hydrocarbons. The hydrocarbons included ethane, ethylene ethyl chloride, methyl chloride, and vinyl chloride. Auger cylindrical mirror analysis was used to follow interactions of the hydrocarbon with the iron surface. Results with vinyl chloride indicate friction induced surface reactivity, adsorption to surface oxides, friction sensitivity to concentration and polymerization. Variation in the loads employed influence adsorption and accordingly friction. In contrast with ethyl and vinyl chloride, friction induced surface reactivity was not observed with ethane and ethylene.

  9. Cyclization Reactions through DDQ-Mediated Vinyl Oxazolidinone Oxidation

    PubMed Central

    Liu, Lei; Floreancig, Paul E.

    2009-01-01

    Vinyl oxazolidinones react with DDQ to form α,β-unsaturated acyliminium ions in a new method for forming electrophiles under oxidative conditions. Appended nucleophiles undergo 1,4-addition reactions with these intermediates to form cyclic vinyl oxazolidinones with good levels of diastereocontrol, highlighting a new approach to utilizing oxidative carbon–hydrogen bond functionalization to increase molecular complexity. PMID:19552390

  10. Ether oxygenate additives in gasoline reduce toxicity of exhausts.

    PubMed

    Westphal, G A; Krahl, J; Brüning, T; Hallier, E; Bünger, J

    2010-02-09

    Fuel additives can improve combustion and knock resistance of gasoline engines. Common additives in commercial fuels are "short-chain, oxygen containing hydrocarbons" such as methyl tert-butyl ether (MTBE) and ethyl tert-butyl ether (ETBE). Since these additives change the combustion characteristics, this may as well influence toxic effects of the resulting emissions. Therefore we compared toxicity and BTEX emissions of gasoline engine exhaust regarding addition of MTBE or ETBE. Non-reformulated gasoline served as basic fuel. This fuel was supplemented with 10%, 20%, 25% and 30% ETBE or 15% MTBE. The fuels were combusted in a gasoline engine at idling, part load and rated power. Condensates and particulate matter (PM) were collected and PM samples extracted with dichloromethane. Cytotoxic effects were investigated in murine fibroblasts (L929) using the neutral red uptake assay and mutagenicity using the bacterial reverse mutation assay. BTEX emissions were analyzed by gas chromatography. PM-extracts showed mutagenicity with and without metabolic activation. Mutagenicity was reduced by the addition of MTBE and ETBE, 10% ETBE being most effective. The condensates produced no significant mutagenic response. The cytotoxicity of the condensates from ETBE- and MTBE-reformulated fuels was reduced as well. The BTEX content in the exhaust was lowered by the addition of MTBE and ETBE. This effect was significantly related to the ETBE content at rated power and part load. Addition of MTBE and ETBE to fuels can improve combustion and leads to decreased toxicity and BTEX content of the exhaust. Reduction of mutagenicity in the PM-extracts is most probably caused by a lower content of polycyclic aromatic hydrocarbons. (c) 2009 Elsevier Ireland Ltd. All rights reserved.

  11. IRIS Toxicological Review of Vinyl Chloride (Final Report, 2000)

    EPA Science Inventory

    EPA is announcing the release of the final report, Toxicological Review of Vinyl Chloride: in support of the Integrated Risk Information System (IRIS). The updated Summary for Vinyl Chloride and accompanying Quickview have also been added to the IRIS Database.

  12. Palladium-Catalyzed Conversion of Aryl and Vinyl Triflates to Bromides and Chlorides

    PubMed Central

    Shen, Xiaoqiang; Hyde, Alan M.; Buchwald, Stephen L.

    2010-01-01

    The palladium-catalyzed conversion of aryl and vinyl triflates to aryl and vinyl halides (bromides and chlorides) has been developed using dialkylbiaryl phosphine ligands. A variety of aryl, heteroaryl and vinyl halides can be prepared via this method in good to excellent yields. PMID:20857936

  13. 40 CFR 413.02 - General definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-bromophenyl phenyl ether Bis (2-chloroisopropyl) ether Bis (2-chloroethoxy) methane Methylene chloride (dichloromethane) Methyl chloride (chloromethane) Methyl bromide (bromomethane) Bromoform (tribromomethane...-phenylene pyrene) Pyrene Tetrachloroethylene Toluene Trichloroethylene Vinyl chloride (chloroethylene...

  14. Mono- and Dialkyl Glycerol Ether Lipids in Anaerobic Bacteria: Biosynthetic Insights from the Mesophilic Sulfate Reducer Desulfatibacillum alkenivorans PF2803T

    PubMed Central

    Mollex, Damien; Vinçon-Laugier, Arnauld; Hakil, Florence; Pacton, Muriel; Cravo-Laureau, Cristiana

    2015-01-01

    Bacterial glycerol ether lipids (alkylglycerols) have received increasing attention during the last decades, notably due to their potential role in cell resistance or adaptation to adverse environmental conditions. Major uncertainties remain, however, regarding the origin, biosynthesis, and modes of formation of these uncommon bacterial lipids. We report here the preponderance of monoalkyl- and dialkylglycerols (1-O-alkyl-, 2-O-alkyl-, and 1,2-O-dialkylglycerols) among the hydrolyzed lipids of the marine mesophilic sulfate-reducing proteobacterium Desulfatibacillum alkenivorans PF2803T grown on n-alkenes (pentadec-1-ene or hexadec-1-ene) as the sole carbon and energy source. Alkylglycerols account for one-third to two-thirds of the total cellular lipids (alkylglycerols plus acylglycerols), depending on the growth substrate, with dialkylglycerols contributing to one-fifth to two-fifths of the total ether lipids. The carbon chain distribution of the lipids of D. alkenivorans also depends on that of the substrate, but the chain length and methyl-branching patterns of fatty acids and monoalkyl- and dialkylglycerols are systematically congruent, supporting the idea of a biosynthetic link between the three classes of compounds. Vinyl ethers (1-alken-1′-yl-glycerols, known as plasmalogens) are not detected among the lipids of strain PF2803T. Cultures grown on different (per)deuterated n-alkene, n-alkanol, and n-fatty acid substrates further demonstrate that saturated alkylglycerols are not formed via the reduction of hypothetic alken-1′-yl intermediates. Our results support an unprecedented biosynthetic pathway to monoalkyl/monoacyl- and dialkylglycerols in anaerobic bacteria and suggest that n-alkyl compounds present in the environment can serve as the substrates for supplying the building blocks of ether phospholipids of heterotrophic bacteria. PMID:25724965

  15. Alternative Fuels Data Center: Dimethyl Ether

    Science.gov Websites

    Hydrocarbon Biofuels Dimethyl Ether Dimethyl ether (DME) is a synthetically produced alternative to diesel for use in specially designed compression ignition diesel engines. Under normal atmospheric conditions ether has several fuel properties that make it attractive for use in diesel engines. It has a very high

  16. 21 CFR 868.5420 - Ether hook.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ether hook. 868.5420 Section 868.5420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5420 Ether hook. (a) Identification. An ether hook is a device...

  17. Thermodynamic equilibrium calculations of hydrogen production from the combined processes of dimethyl ether steam reforming and partial oxidation

    NASA Astrophysics Data System (ADS)

    Semelsberger, Troy A.; Borup, Rodney L.

    Thermodynamic analyses of producing a hydrogen-rich fuel-cell feed from the combined processes of dimethyl ether (DME) partial oxidation and steam reforming were investigated as a function of oxygen-to-carbon ratio (0.00-2.80), steam-to-carbon ratio (0.00-4.00), temperature (100 °C-600 °C), pressure (1-5 atm) and product species. Thermodynamically, dimethyl ether processed with air and steam generates hydrogen-rich fuel-cell feeds; however, the hydrogen concentration is less than that for pure DME steam reforming. Results of the thermodynamic processing of dimethyl ether indicate the complete conversion of dimethyl ether to hydrogen, carbon monoxide and carbon dioxide for temperatures greater than 200 °C, oxygen-to-carbon ratios greater than 0.00 and steam-to-carbon ratios greater than 1.25 at atmospheric pressure (P = 1 atm). Increasing the operating pressure has negligible effects on the hydrogen content. Thermodynamically, dimethyl ether can produce concentrations of hydrogen and carbon monoxide of 52% and 2.2%, respectively, at a temperature of 300 °C, and oxygen-to-carbon ratio of 0.40, a pressure of 1 atm and a steam-to-carbon ratio of 1.50. The order of thermodynamically stable products (excluding H 2, CO, CO 2, DME, NH 3 and H 2O) in decreasing mole fraction is methane, ethane, isopropyl alcohol, acetone, n-propanol, ethylene, ethanol and methyl-ethyl ether; trace amounts of formaldehyde, formic acid and methanol are observed. Ammonia and hydrogen cyanide are also thermodynamically favored products. Ammonia is favored at low temperatures in the range of oxygen-to-carbon ratios of 0.40-2.50 regardless of the steam-to-carbon ratio employed. The maximum ammonia content (i.e., 40%) occurs at an oxygen-to-carbon ratio of 0.40, a steam-to-carbon ratio of 1.00 and a temperature of 100 °C. Hydrogen cyanide is favored at high temperatures and low oxygen-to-carbon ratios with a maximum of 3.18% occurring at an oxygen-to-carbon ratio of 0.40 and a steam

  18. Sequential development of hepatocellular carcinoma and liver angiosarcoma in a vinyl chloride-exposed worker.

    PubMed

    Guido, Maria; Sarcognato, Samantha; Pelletti, Guido; Fassan, Matteo; Murer, Bruno; Snenghi, Rossella

    2016-11-01

    Strong experimental and clinical evidences have definitely linked occupational vinyl chloride exposure to development of angiosarcoma of the liver. In contrast, despite the International Agency for Research on Cancer having included vinyl chloride among the causes of hepatocellular carcinoma, the association between vinyl chloride exposure and hepatocellular carcinoma remains debated. This issue is relevant, because occupational exposure to high levels of vinyl chloride may still occur. We report a unique case of sequential occurrences of hepatocellular carcinoma and angiosarcoma of the liver, in a vinyl chloride-exposed worker without cirrhosis and any known risk factor for chronic liver disease. Both the hepatocellular carcinoma and the surrounding normal liver showed micronucleus formation, which reflects genotoxic effect of vinyl chloride. Angiosarcoma showed a KRAS G12D point mutation, which is considered to be characteristic of vinyl chloride-induced angiosarcoma. This case supports the pathogenic role of vinyl chloride in both hepatocellular carcinoma and angiosarcoma development. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Thermal and chemical stabilization of ethylene/vinyl acetate/vinyl alcohol (EVA-OH) terpolymers under nitroplasticizer environments

    DOE PAGES

    Yang, Dali; Hubbard, Kevin M.; Henderson, Kevin C.; ...

    2014-09-17

    Here, we compare the aging behaviors of cross-linked ethylene/vinyl acetate/vinyl alcohol terpolymers, also referred to as EVA-OH, when they are either immersed in nitroplasticizer (NP) liquid or exposed to NP vapor at different temperatures. And while thermogravimetric analysis and differential scanning calorimetry are used to probe the thermal stability of aged NP and polymers, Fourier transform infrared, gel permeation chromatography, ultra-violet/vis, and nuclear magnetic resonance are used to probe their structural changes over the aging process. Our study confirms that NP degrades through C[BOND]N cleavage, and releases HONO molecules at a slightly elevated temperature (<75°C). As these molecules accumulate inmore » the vapor phase, they react among themselves to create an acidic environment. Therefore, these chemical constituents in the NP vapor significantly accelerate the hydrolysis of EVA-OH polymer. When the hydrolysis occurs in both vinyl acetate and urethane groups and the scission at the cross-linker progresses, EVA-OH becomes vulnerable to further degradation in the NP vapor environment. Finally, through the comprehensive characterization, the possible degradation mechanisms of the terpolymers are proposed.« less

  20. Studies Update Vinyl Chloride Hazards.

    ERIC Educational Resources Information Center

    Rawls, Rebecca

    1980-01-01

    Extensive study affirms that vinyl chloride is a potent animal carcinogen. Epidemiological studies show elevated rates of human cancers in association with extended contact with the compound. (Author/RE)

  1. N-alpha-Cocoyl-L-arginine ethyl ester, DL-pyroglutamic acid salt, as an inactivator of hepatitis B surface antigen.

    PubMed Central

    Sugimoto, Y; Toyoshima, S

    1979-01-01

    N-alpha-Cocoyl-L-arginine ethyl ester, DL-pyroglutamic acid salt (CAE), exhibited a strong inactivating effect on hepatitis B surface antigen. Concentrations of CAE required for 50 and 100% inactivation of the antigen were 0.01 to 0.025% and 0.025 to 0.05% respectively. CAE completely inactivated hepatitis B surface antigen at the lowest concentration compared with various compounds including about 500 amino acid derivatives, sodium hypochlorite, 2,4,4'-trichloro-2'-hydroxydiphenyl ether, and some detergents. Furthermore, CAE inactivated vaccinia virus, herpes simplex virus, and influenza virus, whereas poliovirus was not inactivated at all. The results suggest that the inactivating effects of CAE are related to interaction with lipid-containing viral envelopes. PMID:228595

  2. Angiosarcoma of the liver in Great Britain in proximity to vinyl chloride sites.

    PubMed

    Elliott, P; Kleinschmidt, I

    1997-01-01

    To study the incidence of angiosarcoma of the liver in England and Wales 1979-86 and Scotland 1975-87. To investigate whether any non-occupational neighbourhood cases occurred near a vinyl chloride site. This is a geographical study of incident cases among the general population of Great Britain. Diagnosis of angiosarcoma of the liver was based mainly on the national cancer registry, the world register of cases among vinyl chloride workers, and the register of cases (including histological review) maintained by the Health and Safety Executive. Proximity (< 10 km) of residence to a vinyl chloride site was based on postcode of address at the time of diagnosis. 55 cases were ascribed to angiosarcoma of the liver in England and Wales with a further six cases in Scotland (annual incidence in Great Britain from all sources of around 1.4 cases per 10 million population). There were two cases with documented exposure to Thorotrast, and 10 cases among vinyl chloride workers. There were no vinyl chloride sites in Scotland. Among the 25 cases in England and Wales with histological diagnosis after review by a panel of pathologists, only 15 were confirmed as angiosarcoma, and one of the two Scottish cases after histological review was also confirmed. Overall, 11 cases ascribed to angiosarcoma were resident within 10 km of a vinyl chloride site; nine were vinyl chloride workers, one further case on histological review was not considered to have been correctly diagnosed as angiosarcoma, and the remaining case, confirmed as angiosarcoma, was employed at a vinyl chloride factory during the late 1950s, although not as a vinyl chloride worker. The incidence of angiosarcoma of the liver in Great Britain remains extremely rare. The one confirmed case in a non-vinyl chloride worker within 10 km of a site must nevertheless be presumed to have been exposed to vinyl chloride in the workplace. In the period of study, there were no confirmed non-occupationally exposed cases of angiosarcoma

  3. Angiosarcoma of the liver in Great Britain in proximity to vinyl chloride sites.

    PubMed Central

    Elliott, P; Kleinschmidt, I

    1997-01-01

    OBJECTIVES: To study the incidence of angiosarcoma of the liver in England and Wales 1979-86 and Scotland 1975-87. To investigate whether any non-occupational neighbourhood cases occurred near a vinyl chloride site. METHODS: This is a geographical study of incident cases among the general population of Great Britain. Diagnosis of angiosarcoma of the liver was based mainly on the national cancer registry, the world register of cases among vinyl chloride workers, and the register of cases (including histological review) maintained by the Health and Safety Executive. Proximity (< 10 km) of residence to a vinyl chloride site was based on postcode of address at the time of diagnosis. RESULTS: 55 cases were ascribed to angiosarcoma of the liver in England and Wales with a further six cases in Scotland (annual incidence in Great Britain from all sources of around 1.4 cases per 10 million population). There were two cases with documented exposure to Thorotrast, and 10 cases among vinyl chloride workers. There were no vinyl chloride sites in Scotland. Among the 25 cases in England and Wales with histological diagnosis after review by a panel of pathologists, only 15 were confirmed as angiosarcoma, and one of the two Scottish cases after histological review was also confirmed. Overall, 11 cases ascribed to angiosarcoma were resident within 10 km of a vinyl chloride site; nine were vinyl chloride workers, one further case on histological review was not considered to have been correctly diagnosed as angiosarcoma, and the remaining case, confirmed as angiosarcoma, was employed at a vinyl chloride factory during the late 1950s, although not as a vinyl chloride worker. CONCLUSION: The incidence of angiosarcoma of the liver in Great Britain remains extremely rare. The one confirmed case in a non-vinyl chloride worker within 10 km of a site must nevertheless be presumed to have been exposed to vinyl chloride in the workplace. In the period of study, there were no confirmed non

  4. 40 CFR 721.3152 - Ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates (salts). 721.3152 Section 721... Ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates... ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates...

  5. 40 CFR 721.3152 - Ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates (salts). 721.3152 Section 721... Ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates... ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates...

  6. 40 CFR 721.3152 - Ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates (salts). 721.3152 Section 721... Ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates... ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates...

  7. 40 CFR 721.3152 - Ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates (salts). 721.3152 Section 721... Ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates... ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates...

  8. Synthesis and Mesomorphic Behavior of Poly((2S, 3S)-(+)-2-Chloro-3- Methylpentyl 4’-(Omega-Vinyloxyalkyloxy)biphenyl-4-Carboxylate)s with Ethyl and Propyl Alkyl Groups

    DTIC Science & Technology

    1994-06-30

    1 . Synthesis of (2S, 3S)-(+)-2-chloro-3-methyl-pentyl 4’-(2-vinyloxyethyloxy) biphenyl-4-carboxylate (15-2...CH2)2-),7.65 (d, 3=8.3Hz, 2 ArH, m to -COO-), 8.11 (d, J=7.4Hz, 2 ArH, o to -COO-). 3-Chloroprop~yl- 1 -vinyl ether (13-3) The mixture of 3- chloropropan ...VA .% fo - " A’* *i f’. - % .oL.,ae- a * 1 nOl-6..io. Ocw. ’•.1ý’ ..a.. :l•t :...•.t ;,,31 -. 1 " 1 . 2 . 10 1 -- Of , • l 0’ i’*J.. e t *no suaqetg

  9. Distribution of methyl tert-butyl ether (MTBE) and selected water-quality constituents in the surficial aquifer at the Dover National Test Site, Dover Air Force Base, Delaware, 2001

    USGS Publications Warehouse

    Stewart, Marie; Guertal, William R.; Barbaro, Jeffrey R.; McHale, Timothy J.

    2004-01-01

    A joint study by the Dover National Test Site, Dover Air Force Base, Delaware, and the U.S. Geological Survey was conducted from June 27 through July 18, 2001, to determine the spatial distribution of the gasoline oxygenate additive methyl tert-butyl ether and selected water-quality constituents in the surficial aquifer underlying the Dover National Test Site. This report provides a summary assessment of the distribution of methyl tert-butyl ether and a preliminary screening of selected constituents that may affect natural attenuation and remediation demonstrations at the Dover National Test Site. The information gathered during this study is designed to assist potential remedial investigators who are considering conducting a methyl tert-butyl ether remedial demonstration at the test site. In addition, the study supported a planned enhanced bioremediation demonstration and assisted the Dover National Test Site in identifying possible locations for future methyl tert-butyl ether remediation demonstrations. A direct-push drill rig was used to collect a total of 147 ground-water samples (115 VOC samples and 32 quality-assurance samples) at varying depths. Volatile organic compounds were above the method reporting limits in 59 of the 115 ground-water samples. The concentrations ranged from below detection limits to maximum values of 12.4 micrograms per liter of cis-1,2-dichloro-ethene, 1.14 micrograms per liter of trichloro-ethene, 2.65 micrograms per liter of tetrachloro-ethene, 1,070 micrograms per liter of methyl tert-butyl ether, 4.36 micrograms per liter of benzene, and 1.8 micrograms per liter of toluene. Vinyl chloride, ethylbenzene, p,m-xylene, and o-xylene were not detected in any of the samples collected during this investigation. Methyl tert-butyl ether was detected in 47 of the 115 ground-water samples. The highest concentrations of methyl tert-butyl ether were detected in the surficial aquifer from ?4.6 to 6.4 feet mean sea level; however, methyl tert

  10. Environmental and Chemical Aging of Fatty-Acid-Based Vinyl Ester Composites

    DTIC Science & Technology

    2011-04-01

    Environmental and Chemical Aging of Fatty- Acid -Based Vinyl Ester Composites by Steven E. Boyd and John J. La Scala ARL-TR-5523 April...2011 Environmental and Chemical Aging of Fatty- Acid -Based Vinyl Ester Composites Steven E. Boyd and John J. La Scala Weapons and Materials...COVERED (From - To) October 2009–September 2010 4. TITLE AND SUBTITLE Environmental and Chemical Aging of Fatty- Acid -Based Vinyl Ester Composites

  11. Spectral Photosensitization of Optical Anisotropy in Solid Poly(Vinyl Cinnamate) Films

    NASA Astrophysics Data System (ADS)

    Kozenkov, V. M.; Spakhov, A. A.; Belyaev, V. V.; Chausov, D. N.; Chigrinov, V. G.

    2018-04-01

    The possibility and features of formation of sensitized photoinduced optical anisotropy in amorphous films of poly(vinyl cinnamate) and its derivative poly(vinyl-4-metoxicinnamate) under the action of polarized light (including light that is not absorbed by polymer macromolecules themselves) have been investigated. It is found that the effect of induced optical anisotropy is based on the transfer of electron excitation energy from donor (sensitizer) molecules to acceptor molecules and is observed in the course of phototopochemical biomolecular cyclization reaction of cinnamate fragments in polymer macromolecules. The detected photoinduced anisotropy in solid films of poly(vinyl cinnamate) and its derivative poly(vinyl-4-metoxicinnamate) ensures sensitized photo-orientation of low-molecular thermotropic liquid crystals.

  12. Detection of interstellar ethyl cyanide

    NASA Technical Reports Server (NTRS)

    Johnson, D. R.; Lovas, F. J.; Gottlieb, C. A.; Gottlieb, E. W.; Litvak, M. M.; Thaddeus, P.; Guelin, M.

    1977-01-01

    Twenty-four millimeter-wave emission lines of ethyl cyanide (CH3CH2CN) have been detected in the Orion Nebula (OMC-1) and seven in Sgr B2. To derive precise radial velocities from the astronomical data, a laboratory measurement of the rotational spectrum of ethyl cyanide has been made at frequencies above 41 GHz. In OMC-1, the rotational temperature of ethyl cyanide is 90 K (in good agreement with other molecules), the local-standard-of-rest radial velocity is 4.5 + or - 1.0 km/s (versus 8.5 km/s for most molecules), and the column density is 1.8 by 10 to the 14th power per sq cm (a surprisingly high figure for a complicated molecule). The high abundance of ethyl cyanide in the Orion Nebula suggests that ethane and perhaps larger saturated hydrocarbons may be common constituents of molecular clouds and have escaped detection only because they are nonpolar or only weakly polar.

  13. Vinyl chloride removal from an air stream by biotrickling filter.

    PubMed

    Faraj, S H Esmaeili; Esfahany, M Nasr; Kadivar, M; Zilouei, H

    2012-01-01

    A biofiltration process was used for degradation of vinyl chloride as a hazardous material in the air stream. Three biotrickling filters in series-parallel allowing uniform feed and moisture distribution all over the bed were used. Granular activated carbon mixed with compost was employed as carrier bed. The biological culture consisted of mixture of activated sludge from PVC wastewater treatment plant. Concurrent flow of gas and liquid was used in the bed. Results indicated that during the operation period of 110 days, the biotrickling bed was able to remove over 35% of inlet vinyl chloride. Maximum elimination capacity was calculated to be 0.56 g.m(-3).hr(-1). The amount of chlorine accumulated in the circulating liquid due to the degradation of vinyl chloride was measured to be equal to the vinyl chloride removed from the air stream.

  14. Spiroborate Ester-Mediated Asymmetric Synthesis of β-Hydroxy Ethers and its Conversion to Highly Enantiopure β-Amino Ethers

    PubMed Central

    Huang, Kun; Ortiz-Marciales, Margarita; Correa, Wildeliz; Pomales, Edgardo; López, Xaira Y.

    2009-01-01

    Borane-mediated reduction of aryl and alkyl ketones with α-aryl- and α-pyridyloxy groups affords β-hydroxy ethers in high enantiomeric purity (up to 99% ee) and in good yield, using as catalyst 10 mol % of spiroborate ester 1 derived from (S)-diphenylprolinol. Representative β-hydroxy ethers are successfully converted to β-amino ethers, with minor epimerization, by phthalimide substitution under Mitsunobu’s conditions followed by hydrazinolysis, to obtain primary amino ethers or by imide reduction with borane to afford β-2,3-dihydro-1H-isoindol ethers. Non-racemic Mexiletine and nAChR analogues with potential biological activity are also synthesized in excellent yield by mesylation of key β-hydroxy pyridylethers and substitution with 5, 6 and 7 member ring heterocyclic amines. PMID:19413288

  15. 40 CFR 180.430 - Fenoxaprop-ethyl; tolerances for residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... combined residues of the herbicide fenoxaprop-ethyl [(±)-ethyl 2-[4-[(6-chloro-2-benzoxazolyl)oxy]phenoxy... herbicide fenoxaprop-ethyl, [(±)-ethyl 2-[4-[(6-chloro-2-benzoxazolyl)oxy]phenoxy]propanoic acid], and its...

  16. Proton-conducting membrane based on epoxy resin-poly(vinyl alcohol)-sulfosuccinic acid blend and its nanocomposite with sulfonated multiwall carbon nanotubes for fuel-cell application

    NASA Astrophysics Data System (ADS)

    Kakati, Nitul; Das, Gautam; Yoon, Young Soo

    2016-01-01

    A blend of poly(vinyl alcohol) (PVA) with diglycidyl ether of bisphenol-A (DGB) in the presence of sulfosuccinic acid (SSA) was investigated as hydrolytically-stable proton-conducting membrane. The PVA modification was carried out by varying the DGB:SSA ratio (20:20, 10:20, and 5:20). A nanocomposite of the blend (20:20) was prepared with sulfonated multiwall carbon nanotubes (viz., 1, 3 and 5 wt%). The water uptake behavior and the proton conductivity of the prepared membranes were evaluated. The ionic conductivity of the membranes and the water uptake behavior depended on the s-MWCNT and the DGB contents. The ionic conductivity showed an enhancement for the blend and for the nanocomposite membrane as compared to the pristine polymer.

  17. From ether theory to ether theology: Oliver Lodge and the physics of immortality.

    PubMed

    Raia, Courtenay Grean

    2007-01-01

    This article follows the development of physicist Oliver Lodge's religio-scientific worldview, beginning with his reticent attraction to metaphysics in the early 1880s to the full formulation of his "ether theology" in the late 1890s. Lodge undertook the study of psychical phenomena such as telepathy, telekinesis, and "ectoplasm" to further his scientific investigations of the ether, speculating that electrical and psychical manifestations were linked phenomena that described the deeper underlying structures of the universe, beneath and beyond matter. For Lodge, to fully understand the ether was to force from the universe an ultimate Revelation, and psychical research, as the most modern and probatory science, was poised to replace religion as the means of that disclosure. (c) 2007 Wiley Periodicals, Inc.

  18. Microfluidic solvent extraction of poly(vinyl alcohol) droplets: effect of polymer structure on particle and capsule formation.

    PubMed

    Sharratt, W N; Brooker, A; Robles, E S J; Cabral, J T

    2018-04-26

    We investigate the formation of poly(vinyl alcohol) microparticles by the selective extraction of aqueous polymer solution droplets, templated by microfluidics and subsequently immersed in a non-solvent bath. The role of polymer molecular mass (18-105 kg mol-1), degree of hydrolysis (88-99%) and thus solubility, and initial solution concentration (0.01-10% w/w) are quantified. Monodisperse droplets with radii ranging from 50 to 500 μm were produced at a flow-focusing junction with carrier phase hexadecane and extracted into ethyl acetate. Solvent exchange and extraction result in droplet shrinkage, demixing, coarsening and phase-inversion, yielding polymer microparticles with well-defined dimensions and internal microstructure. Polymer concentration, varied from below the overlap concentration c* to above the concentrated crossover c**, as estimated by viscosity measurements, was found to have the largest impact on the final particle size and extraction timescale, while polymer mass and hydrolysis played a secondary role. These results are consistent with the observation that the average polymer concentration upon solidification greatly exceeds c**, and that the internal microparticle porosity is largely unchanged. However, reducing the initial polymer concentration to well below c* (approximately 100×) and increasing droplet size yields thin-walled (100's of nm) capsules which controllably crumple upon extraction. The symmetry of the process can be readily broken by imposing extraction conditions at an impermeable surface, yielding large, buckled, cavity morphologies. Based on these results, we establish robust design criteria for polymer capsules and particles, demonstrated here for poly(vinyl alcohol), with well-defined shape, dimensions and internal microstructure.

  19. Lewis base catalyzed aldol additions of chiral trichlorosilyl enolates and silyl enol ethers.

    PubMed

    Denmark, Scott E; Fujimori, Shinji; Pham, Son M

    2005-12-23

    [structures: see text] The consequences of double diastereodifferentiation in chiral Lewis base catalyzed aldol additions using chiral enoxysilanes derived from lactate, 3-hydroxyisobutyrate, and 3-hydroxybutyrate have been investigated. Trichlorosilyl enolates derived from the chiral methyl and ethyl ketones were subjected to aldolization in the presence of phosphoramides, and the intrinsic selectivity of these enolates and the external stereoinduction from chiral catalyst were studied. In the reactions with the lactate derived enolate, the strong internal stereoinduction dominated the stereochemical outcome of the aldol addition. For the 3-hydroxyisobutyrate- and 3-hydroxybutyrate derived enolates, the catalyst-controlled diastereoselectivities were observed, and the resident stereogenic centers exerted marginal influence. The corresponding trimethylsilyl enol ethers were employed in SiCl4/bisphosphoramide catalyzed aldol additions, and the effect of double diastereodifferentiation was also investigated. The overall diastereoselection of the process was again controlled by the strong external influence of the catalyst.

  20. Skin sterility after application of ethyl chloride spray.

    PubMed

    Polishchuk, Daniil; Gehrmann, Robin; Tan, Virak

    2012-01-18

    Ethyl chloride topical anesthetic spray is labeled as nonsterile, yet it is widely used during injection procedures performed in an outpatient setting. The purpose of this study was to investigate the sterility of ethyl chloride topical anesthetic spray applied before an injection. Our a priori hypothesis was that application of the spray after the skin has been prepared would not alter the sterility of the injection site. We conducted a prospective, blinded, controlled study to assess the effect of ethyl chloride spray on skin sterility. Fifteen healthy adult subjects (age, twenty-three to sixty-one years) were prepared for mock injections into both shoulders and both knees, although no injection was actually performed. Three culture samples were obtained from each site on the skin: one before skin preparation with isopropyl alcohol, one after skin preparation and before application of ethyl chloride, and one after ethyl chloride had been sprayed on the site. In addition, the sterility of the ethyl chloride was tested directly by inoculating cultures with spray from the bottles. Growth occurred in 70% of the samples obtained before skin preparation, 3% of the samples obtained after skin preparation but before application of ethyl chloride, and 5% of the samples obtained after the injection site had been sprayed with ethyl chloride. The percentage of positive cultures did not increase significantly after application of ethyl chloride (p = 0.65). Spraying of ethyl chloride directly on agar plates resulted in growth on 13% of these plates compared with 11% of the control plates; this difference was also not significant (p = 0.80). Although ethyl chloride spray is not sterile, its application did not alter the sterility of the injection sites in the shoulder and knee.

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

    NASA Astrophysics Data System (ADS)

    Turner, Josh; Menary, Gary; Martin, Peter

    2018-05-01

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

  2. Molecular glass positive i-line photoresist materials containing 2,1,4-DNQ and acid labile group

    NASA Astrophysics Data System (ADS)

    Wang, Liyuan; Yu, Jinxing; Xu, Na

    2010-04-01

    Recent years increasing attention has been given to molecular glass resist materials. In this paper, maleopimaric acid, cycloaddition reaction product of rosin with maleic anhydride, was reacted with hydroxylamine and then further esterified with 2-diazo-1-naphthoquinone-4-sulfonyl chloride to give N-hydroxy maleopimarimide sulfonate. The carboxylic acid group of the compound was then protected by the reaction of this compound with vinyl ethyl ether or dihydropyran. Thus obtained compounds were amorphous. When irradiated with i-line light, the 2,1,4-DNQ group undergo photolysis not only to give off nitrogen gas but also generate sulfonic acid which can result in the decomposition of the acid labile group. So, a novel chemically amplified positive i-line molecular glass photoresists can be formed by the compound and other acidolytic molecular glass compounds. The lithographic performance of the resist materials is evaluated.

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

    PubMed

    Zhu, Yuanqin; Zieren, Shelley; Manthiram, Arumugam

    2011-07-14

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

  4. Laser Spectroscopy of Vinyl Alcohol Embedded in Helium Droplets

    NASA Astrophysics Data System (ADS)

    Bunn, Hayley; Raston, Paul; Douberly, Gary E.

    2017-06-01

    Vinyl alcohol has two rotameric forms, known as syn- and anti-vinyl alcohol, where syn is the most stable. While both have been investigated by microwave and far-infrared spectroscopy, only the syn rotamer has been investigated by mid-infrared spectroscopy. This is due to the low anti rotamer population (15%) at room temperature, in addition to the closeness in proximity of the mid-infrared bands between the rotamers; this results in overlapping bands that are dominated by syn-vinyl alcohol absorptions. In this investigation we increase the anti-vinyl alcohol population to 40% by using a high temperature "pyrolysis" source, and eliminate the spectral overlap by recording the spectra at low temperature in helium nanodroplets. We observe a number of bands of both rotamers in the OH, CH, and CO stretching regions that display rotational substructure. A highlight of this work is the observation of a Fermi dyad in the OH stretching region of anti-vinyl alcohol. Anharmonic frequency calculations suggest that this is due to a near degeneracy of the OH stretching state (νb{1}) with a triple combination involving νb{7}, νb{8}, and νb{9}. M. Rodler, J. Mol. Spec. 114, 23 (1985);S. Saito, Chem. Phys. Lett. 42, 3 (1976) H. Bunn, R. Hudson, A. S. Gentleman, and P. L. Raston, ACS Earth Space Chem. DOI: 10.1021/acsearthspacechem.6b00008 (2017) D-L Joo, A. J. Merer, D. J. Clouthier, J. Mol. Spec. 197, 68 (1999)

  5. [Simultaneous determination of ethyl carbamate and chloropropanols in flavorings by gas chromatography-triple quadrupole tandem mass spectrometry].

    PubMed

    Xu, Xiaomin; He, Huali; Ruan, Yudi; Huang, Baifen; Zhang, Jingshun; Cai, Zengxuan; Ren, Yiping

    2013-11-01

    A simultaneous determination method for ethyl carbamate (EC) and chloropropanols (3-monochloropropane-1, 2-diol (3-MCPD) and 2-monochloropropane-1, 3-diol (2-MCPD)) in flavorings was developed by gas chromatography-triple quadrupole tandem mass spectrometry (GC-MS/MS). After spiked with internal standard, the sample was extracted by matrix solid-phase dispersion extraction technique with an Extrelut NT column. Hexane was used to wash the fat soluble matrix interferences and then an ethyl acetate-ethyl ether (20: 80, v/v) mixture was added to elute the analytes. The concentrated extract was detected by GC-MS/MS in multiple reaction monitoring (MRM) mode. The limits of detection (LODs) were 2, 5 and 5 microg/kg for EC, 3-MCPD and 2-MCPD, respectively. The linear ranges were 5 - 1 000 microg/kg (r = 0.9997), 10-1000 microg/kg (r = 0.999 1) and 10-1000 microg/kg (r = 0.999 5) for EC, 3-MCPD and 2-MCPD, respectively. In soy sauce, yellow rice wine, salami sauce and flavoring of instant noodle matrices, the recoveries (RSDs, n = 7) in MRM mode at the levels of 20, 100 and 400 microg/kg were 87.7%-104% (4.3%-10.7%), 90.1%-109% (2.6%-10.2%), and 90.9%-103% (3.0%-9.5%), respectively. EC, 3-MCPD and 2-MCPD were found in some real samples of the soy sauce, wine and flavoring of instant noodle. EC or 3-MCPD was found in some of the salami samples. The method is accurate, fast and suitable for the simultaneous determination of EC, 3-MCPD and 2-MCPD in flavorings.

  6. Icosapent Ethyl

    MedlinePlus

    ... doctor if you have or have ever had diabetes or liver, thyroid, or pancreatic disease.tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking icosapent ethyl, ...

  7. Fabrication of polymerized crystalline colloidal array thin film modified β-cyclodextrin polymer for paraoxon-ethyl and parathion-ethyl detection.

    PubMed

    Bui, Minh-Phuong N; Seo, Seong S

    2014-01-01

    We have developed an optical chemical sensor for the detection of organophosphate (OP) compounds using a polymerized crystalline colloidal array (PCCA) thin film composed of a close-packed colloidal array of polystyrene particles. The PCCA thin film was modified with β-cyclodextrin (β-CD) polymer as a capping cavity for the selective detection of paraoxon-ethyl and parathion-ethyl chemical agents. The fabrication of the modified PCCA thin film was optimized and the structure was characterized using scanning electron microscopy (SEM). The arrangement of polystyrene particles in the PCCA follows a pattern of the fcc (111) planes with strong diffraction peak in the visible spectral region and pH dependence. The diffraction peak of the β-CD modified PCCA thin film showed a red shift according to the change of paraoxon-ethyl and parathion-ethyl concentrations at a fast response time (10 s) and high sensitivity with detection limits of 2.0 and 3.4 ppb, respectively. Furthermore, the proposed interaction mechanism of β-CD with paraoxon-ethyl and parathion-ethyl in the β-CD modified PCCA thin film were discussed.

  8. Keeping ether "en-vogue": the role of Nathan Cooley Keep in the history of ether anesthesia.

    PubMed

    Guralnick, Walter C; Kaban, Leonard B

    2011-07-01

    In this report, we explore the little known role of Dr Nathan Cooley Keep in the dissemination of ether anesthesia in Boston. Keep was a prominent Boston dentist who, for a short time, taught and employed both William Morton and Horace Wells. He used ether anesthesia for a variety of dental and other surgical procedures requiring pain control. Keep administered ether to anesthetize Henry Wadsworth Longfellow's wife during the delivery of their daughter. This was the first use of ether for obstetric anesthesia. Dr Keep was also the first Dean of the Harvard Dental School and convinced the Massachusetts General Hospital to appoint a dentist to the staff of the hospital for the first time. Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  9. ALMA Spectroscopy of Titan's Atmosphere: First Detections of Vinyl Cyanide and Acetonitrile Isotopologues

    NASA Astrophysics Data System (ADS)

    Cordiner, Martin; Y Palmer, Maureen; Nixon, Conor A.; Charnley, Steven B.; Mumma, Michael J.; Irwin, Pat G. J.; Teanby, Nick A.; Kisiel, Zbigniew; Serigano, Joseph

    2015-11-01

    Studies of Titan's atmospheric chemistry provide a unique opportunity to explore the origin and evolution of complex organic matter in primitive planetary atmospheres. The Atacama Large Millimeter/submillimeter Array (ALMA) is a powerful new telescope, well suited to the study of molecular emission from Titan's stratosphere and mesosphere. Here we present early results from our ongoing study to exploit the large volume of Titan data taken using ALMA in Early Science Mode (during the period 2012-2014). Combining data from multiple ALMA Band 6 observations, we obtained high-resolution mm-wave spectra with unprecedented sensitivity, enabling the first detection of vinyl cyanide (C2H3CN) in Titan's atmosphere. Initial estimates indicate a mesospheric abundance ratio with respect to ethyl cyanide (C2H5CN) of [C2H3CN]/[C2H5CN] = 0.31. In addition, we report the first detections on Titan of the 13C and 15N-substituted isotopologues of acetonitrile (13CH3CN and CH3C15N). Radiative transfer models and possible chemical formation pathways for these molecules will be discussed.

  10. Biodegradation of bis(1-chloro-2-propyl) ether via initial ether scission and subsequent dehalogenation by Rhodococcus sp. strain DTB.

    PubMed

    Moreno Horn, Marcus; Garbe, Leif-Alexander; Tressl, Roland; Adrian, Lorenz; Görisch, Helmut

    2003-04-01

    Rhodococcus sp. strain DTB (DSM 44534) grows on bis(1-chloro-2-propyl) ether (DDE) as sole source of carbon and energy. The non-chlorinated diisopropyl ether and bis(1-hydroxy-2-propyl) ether, however, did not serve as substrates. In ether degradation experiments with dense cell suspensions, 1-chloro-2-propanol and chloroacetone were formed, which indicated that scission of the ether bond is the first step while dehalogenation of the chlorinated C(3)-compounds occurs at a later stage of the degradation pathway. Inhibition of ether scission by methimazole suggested that the first step in degradation is catalyzed by a flavin-dependent enzyme activity. The non-chlorinated compounds 1,2-propanediol, hydroxyacetone, lactate, pyruvate, 1-propanol, propanal, and propionate also supported growth, which suggested that the intermediates 1,2-propanediol and hydroxyacetone are converted to pyruvate or to propionate, which can be channeled into the citric acid cycle by a number of routes. Total release of chloride and growth-yield experiments with DDE and non-chlorinated C(3)-compounds suggested complete biodegradation of the chlorinated ether.

  11. Chlorimuron-ethyl

    Integrated Risk Information System (IRIS)

    Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Chlorimuron - ethyl

  12. Chemistry and adhesive properties of poly(arylene ether)s containing heterocyclic units

    NASA Technical Reports Server (NTRS)

    Connell, John W.

    1991-01-01

    Novel poly(arylene ether)s containing heterocyclic units were prepared, characterized, and evaluated as adhesives and composite matrices. The polymers were prepared by reacting a heterocyclic bisphenol with an activated aromatic dihalide in a polar aprotic solvent, using potassium carbonate. The polymerizations were generally carried out in N,N-dimethylacetamide at 155 C. In some cases, where the polymers were semicrystalline, higher temperatures and thus higher boiling solvents were necessary to keep the polymers in solution. Heterocyclic rings incorporated into the poly(arylene ether) backbone include phenylquinoxaline, phenylimidazole, benzimidazole, benzoxazole, 1,3,4-oxadiazole, and 1,2,4-triazole. The polymers were characterized by differential scanning calorimetry, solution viscosity, X-ray diffraction, thin film, and adhesive and (in some cases) composite properties. The glass transition temperatures, crystalline melt temperature, solubility, and mechanical properties varied depending upon the heterocyclic ring. The chemistry and properties of these materials are discussed.

  13. Determination of Vinyl Chloride at ug/l. Level in Water by Gas Chromatography

    ERIC Educational Resources Information Center

    Bellar, Thomas A.; And Others

    1976-01-01

    A quantitative method for the determination of vinyl chloride in water is presented. Vinyl chloride is transfered to the gas phase by bubbling inert gas through the water. After concentration on silica gel or Carbosieve-B, determination is by gas chromatography. Confirmation of vinyl chloride is by gas chromatography-mass spectrometry. (Author/BT)

  14. Nitrosamine-induced carcinogenesis. The alkylation of N-7 of guanine of nucleic acids of the rat by diethylnitrosamine, N-ethyl-N-nitrosourea and ethyl methanesulphonate

    PubMed Central

    Swann, P. F.; Magee, P. N.

    1971-01-01

    1. The extent of ethylation of N-7 of guanine in the nucleic acids of rat tissue in vivo by diethylnitrosamine, N-ethyl-N-nitrosourea and ethyl methanesulphonate was measured. 2. All compounds produced measurable amounts of 7-ethyl-guanine. 3. A single dose of diethylnitrosamine or N-ethyl-N-nitrosourea produced tumours of the kidney in the rat. Three doses of ethyl methanesulphonate produced kidney tumours, but a single dose did not. 4. A single dose of diethylnitrosamine produced twice as much ethylation of N-7 of guanine in DNA of kidney as did N-ethyl-N-nitrosourea. A single dose of both compounds induced kidney tumours, although of a different histological type. 5. A single dose of ethyl methanesulphonate produced ten times as much ethylation of N-7 of guanine in kidney DNA as did N-ethyl-N-nitrosourea without producing tumours. 6. The relevance of these findings to the hypothesis that alkylation of a cellular component is the mechanism of induction of tumours by nitroso compounds is discussed. PMID:5145908

  15. Preparation of robust braid-reinforced poly(vinyl chloride) ultrafiltration hollow fiber membrane with antifouling surface and application to filtration of activated sludge solution.

    PubMed

    Zhou, Zhuang; Rajabzadeh, Saeid; Fang, Lifeng; Miyoshi, Taro; Kakihana, Yuriko; Matsuyama, Hideto

    2017-08-01

    Braid-reinforced hollow fiber membranes with high mechanical properties and considerable antifouling surface were prepared by blending poly(vinyl chloride) (PVC) with poly(vinyl chloride-co-poly(ethylene glycol) methyl ether methacrylate) (poly(VC-co-PEGMA)) copolymer via non-solvent induced phase separation (NIPS). The tensile strength of the braid-reinforced PVC hollow fiber membranes were significantly larger than those of previously reported various types of PVC hollow fiber membranes. The high interfacial bonding strength indicated the good compatibility between the coating materials and the surface of polyethylene terephthalate (PET)-braid. Owing to the surface segregation phenomena, the membrane surface PEGMA coverage increased upon increasing the poly(VC-co-PEGMA)/PVC blending ratio, resulting in higher hydrophilicities and bovine serum albumin (BSA) repulsion. To compare the fouling properties, membranes with similar PWPs were prepared by adjusting the dope solution composition to eliminate the effect of hydrodynamic conditions on the membrane fouling performance. The blend membranes surface exhibited considerable fouling resistance to the molecular adsorption from both BSA solution and activated sludge solution. In both cases, the flux recovered to almost 80% of the initial flux using only water backflush. Considering their great mechanical properties and antifouling resistance to activated sludge solution, these novel membranes show good potential for application in wastewater treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Vintage Vinyl Record Design

    ERIC Educational Resources Information Center

    Sacco, Michael

    2008-01-01

    In this article, the author describes a project in which his ninth-grade art students utilized a vinyl record as an unusual medium to create a work that exhibited solid design, great creativity, and strong craftsmanship. Students presented their pieces to the class for critique, explained the process, the media, and their feelings about their…

  17. Formation of vinyl halides via a ruthenium-catalyzed three-component coupling.

    PubMed

    Trost, Barry M; Pinkerton, Anthony B

    2002-06-26

    The ruthenium-catalyzed three-component coupling of an alkyne, an enone, and halide ion to form E- or Z-vinyl halides has been investigated. Through systematic optimization experiments, the conditions effecting the olefin selectivity were examined. In general, more polar solvents such as DMF favored the formation of the E-isomer, and less polar solvents such as acetone favored formation of the Z-isomer. The optimized conditions for the formation of E-vinyl chlorides were found to be the use of cyclopentadienyl ruthenium (II) cyclooctadiene chloride, stannic chloride pentahydrate as a cocatalyst, and for a chloride source, either ammonium chloride in DMF/water mixtures or tetramethylammonium chloride in DMF. A range of several other ruthenium (II) catalysts was also shown to be effective. A wide variety of vinyl chlorides could be formed under these conditions. Substrates with tethered alcohols or ketones either five or six carbons from the alkyne portion gave instead diketone or cyclohexenone products. For formation of vinyl bromides, a catalyst system involving the use of cyclopentadienylruthenium (II) tris(acetonitrile) hexafluorophosphate with stannic bromide as a cocatalyst was found to be most effective. The use of ammonium bromide in DMF/acetone mixtures was optimal for the synthesis of E-vinyl bromides, and the use of lithium bromide in acetone was optimal for formation of the corresponding Z-isomer. Under either set of conditions, a wide range of vinyl bromides could be formed. When alkynes with propargylic substituents are used, enhanced selectivity for formation of the Z-isomer is observed. When aryl acetylenes are used as the coupling partners, complete selectivity for the Z-isomer is obtained. A mechanism involving a cis or trans halometalation is invoked to explain formation of the observed products. The vinyl halides have been shown to be precursors to alpha-hydroxy ketones and cyclopentenones, and as coupling partners in Suzuki-type reactions.

  18. Imide/arylene ether copolymers

    NASA Technical Reports Server (NTRS)

    Jensen, Brian J. (Inventor); Hergenrother, Paul M. (Inventor); Bass, Robert G. (Inventor)

    1992-01-01

    Imide/arylene ether block copolymers are prepared by reacting anhydride terminated poly(amic acids) with amine terminated poly(arylene ethers) in polar aprotic solvents and by chemically or thermally cyclodehydrating the resulting intermediate poly(amic acids). The resulting block copolymers have one glass transition temperature or two, depending upon the particular structure and/or the compatibility of the block units. Most of these block copolymers form tough, solvent resistant films with high tensile properties.

  19. 77 FR 12328 - Agency Information Collection Activities; Submission for OMB Review; Comment Request; Vinyl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-29

    ... for OMB Review; Comment Request; Vinyl Chloride Standard ACTION: Notice. SUMMARY: The Department of... collection request (ICR) titled, ``Vinyl Chloride Standard,'' to the Office of Management and Budget (OMB... email at [email protected] . SUPPLEMENTARY INFORMATION: The purpose of the Vinyl Chloride Standard...

  20. 40 CFR 721.10484 - Siloxanes and Silicones, Me vinyl, hydroxy-terminated, reaction products with...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Siloxanes and Silicones, Me vinyl... Substances § 721.10484 Siloxanes and Silicones, Me vinyl, hydroxy-terminated, reaction products with...) The chemical substance identified as Siloxanes and Silicones, Me vinyl, hydroxy-terminated, reaction...

  1. 40 CFR 721.10484 - Siloxanes and Silicones, Me vinyl, hydroxy-terminated, reaction products with...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Siloxanes and Silicones, Me vinyl... Substances § 721.10484 Siloxanes and Silicones, Me vinyl, hydroxy-terminated, reaction products with...) The chemical substance identified as Siloxanes and Silicones, Me vinyl, hydroxy-terminated, reaction...

  2. Aza crown ether compounds as anion receptors

    DOEpatents

    Lee, Hung Sui; Yang, Xiao-Oing; McBreen, James

    1998-08-04

    A family of aza-ether based compounds including linear, multi-branched and aza-crown ethers is provided. When added to non-aqueous battery electrolytes, the new family of aza-ether based compounds acts as neutral receptors to complex the anion moiety of the electrolyte salt thereby increasing the conductivity and the transference number of LI.sup.+ ion in alkali metal batteries.

  3. Aza crown ether compounds as anion receptors

    DOEpatents

    Lee, H.S.; Yang, X.O.; McBreen, J.

    1998-08-04

    A family of aza-ether based compounds including linear, multi-branched and aza-crown ethers is provided. When added to non-aqueous battery electrolytes, the new family of aza-ether based compounds acts as neutral receptors to complex the anion moiety of the electrolyte salt thereby increasing the conductivity and the transference number of LI{sup +} ion in alkali metal batteries. 3 figs.

  4. Azidated Ether-Butadiene-Ether Block Copolymers as Binders for Solid Propellants

    NASA Astrophysics Data System (ADS)

    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.

  5. Ethyl acetate

    Integrated Risk Information System (IRIS)

    Ethyl acetate ; CASRN 141 - 78 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  6. Ethyl chloride

    Integrated Risk Information System (IRIS)

    Ethyl chloride ; CASRN 75 - 00 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  7. Ethyl carbamate

    Integrated Risk Information System (IRIS)

    Ethyl carbamate ; CASRN 51 - 79 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Ef

  8. Ultrasound promoted N-alkylation of pyrrole using potassium superoxide as base in crown ether.

    PubMed

    Yim, E S; Park, M K; Han, B H

    1997-04-01

    Ultrasound accelerates the N-alkylation of pyrrole by alkylating reagents using potassium superoxide as base in the presence of 18-crown-6. A much lower yield of N-alkylated pyrrole was realized in the absence of ultrasound. N-alkylating reagents employed for pyrrole are methyl iodide, ethyl bromide, benzyl bromide, as well as acrylonitrile allyl cyanide and methyl acrylate. In an extension of this work, we have found that ultrasound was not necessary for the N-alkylation of indole and alkyl amine, such as diphenyl amine and piperidine with alkyl halides using our reagents. In all cases we observed that the 18-crown-6 catalyzed N-alkylation reaction gives higher yields of N-alkylated products than that without crown ether, when potassium superoxide was used as base. These observations are probably due to the potassium-crown complex which can be released when the reaction goes to completion.

  9. Development of a category approach to predict the testicular toxicity of chemical substances structurally related to ethylene glycol methyl ether.

    PubMed

    Yamada, Takashi; Tanaka, Yushiro; Hasegawa, Ryuichi; Sakuratani, Yuki; Yamazoe, Yasushi; Ono, Atsushi; Hirose, Akihiko; Hayashi, Makoto

    2014-12-01

    We propose a category approach to assessing the testicular toxicity of chemicals with a similar structure to ethylene glycol methyl ether (EGME). Based on toxicity information for EGME and related chemicals and accompanied by adverse outcome pathway information on the testicular toxicity of EGME, this category was defined as chemicals that are metabolized to methoxy- or ethoxyacetic acid, a substance responsible for testicular toxicity. A Japanese chemical inventory was screened using the Hazard Evaluation Support System, which we have developed to support a category approach for predicting the repeated-dose toxicity of chemical substances. Quantitative metabolic information on the related chemicals was then considered, and seventeen chemicals were finally obtained from the inventory as a shortlist for the category. Available data in the literature shows that chemicals for which information is available on the metabolic formation of EGME, ethylene glycol ethyl ether, methoxy- or ethoxyacetic acid do in fact possess testicular toxicity, suggesting that testicular toxicity is a concern, due to metabolic activation, for the remaining chemicals. Our results clearly demonstrate practical utility of AOP-based category approach for predicting repeated-dose toxicity of chemicals. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. The Discovery of Crown Ethers

    NASA Astrophysics Data System (ADS)

    Pedersen, Charles J.

    1988-07-01

    The discovery of the crown ethers stemmed from efforts to control the catalytic activity of vanadium and copper by complexation with multidentate ligands. The first crown ether, 2,3,11,12-dibenzo-1,4,7,10,13,16-hexaoxacyclo-octadeca-2,11-diene, was obtained in 0.4% yield during an attempt to prepare a phenolic ligand from catechol and bis(2-chloroethyl)ether. This compound, which complexed with the sodium cation, was the first compound known to display such activity and became known as dibenzo-18-crown-6, an 18-atom heterocycle containing 6 oxygen atoms. Some 60 related compounds were made involving heterocyclic rings containing 12 to 60 atoms including 4 and 10 oxygen atoms. There are optimum polyether ring sizes for the different alkali metal cations: 15 to 18 for sodium, 18 for potassium, and 18 to 21 for cesium. Complexes having polyether to cation ratios of 1:1, 3:2, and 2:1 were prepared. Solubilization of inorganic salts in aprotic solvents, especially by saturated crown ethers, was demonstrated.

  11. 21 CFR 177.1320 - Ethylene-ethyl acrylate copolymers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene-ethyl acrylate copolymers. 177.1320... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1320 Ethylene-ethyl acrylate copolymers. Ethylene-ethyl acrylate copolymers may be safely used to produce packaging materials, containers...

  12. Separation of gases through gas enrichment membrane composites

    DOEpatents

    Swedo, R.J.; Kurek, P.R.

    1988-07-19

    Thin film composite membranes having as a permselective layer a film of a homopolymer of certain vinyl alkyl ethers are useful in the separation of various gases. Such homopolymers have a molecular weight of greater than 30,000 and the alkyl group of the vinyl alkyl monomer has from 4 to 20 carbon atoms with branching within the alkyl moiety at least at the carbon atom bonded to the ether oxygen or at the next adjacent carbon atom. These membranes show excellent hydrolytic stability, especially in the presence of acidic or basic gaseous components.

  13. Separation of gases through gas enrichment membrane composites

    DOEpatents

    Swedo, Raymond J.; Kurek, Paul R.

    1988-01-01

    Thin film composite membranes having as a permselective layer a film of a homopolymer of certain vinyl alkyl ethers are useful in the separation of various gases. Such homopolymers have a molecular weight of greater than 30,000 and the alkyl group of the vinyl alkyl monomer has from 4 to 20 carbon atoms with branching within the alkyl moiety at least at the carbon atom bonded to the ether oxygen or at the next adjacent carbon atom. These membranes show excellent hydrolytic stability, especially in the presence of acidic or basic gaseous components.

  14. Chemistry and phytotoxicity of thaxtomin A alkyl ethers.

    PubMed

    Krasnoff, Stuart B; Lobkovsky, Emil B; Wach, Michael J; Loria, Rosemary; Gibson, Donna M

    2005-11-30

    The thaxtomin phytotoxins (1 and 2) from scab-producing Streptomyces pathogens of the potato are 2,5-dioxopiperazines consisting of modified l-tryptophanyl and l-phenylalanyl units. Thaxtomin A (1) is hydroxylated at C-14, the alpha carbon of the modified l-phenylalanyl moiety. Refluxing thaxtomin A in acidified MeOH, EtOH, and i-PrOH afforded C-14 thaxtomin A methyl- (3a and 3b), ethyl- (4a and 4b), and isopropyl- (5a and 5b) ethers, respectively, in both the 11S,14R (3a, 4a, and 5a) and 11S,14S (3b, 4b, and 5b) configurations. Crystal structures were determined for 3a and 4a. Extensive NMR as well as other spectroscopic data supported structural assignments for all of the derivatives. The 11S,14R-configured derivatives were slightly less potent than the natural products (1 and 2) as inhibitors of lettuce seedling root growth, whereas the activity of the 11S,14S epimers was much reduced, indicating that the configuration at C-14 found in the naturally occurring thaxtomins is essential for biological activity. Among the 11S,14R-configured compounds, potency decreased with an increasing size of the substituted alkoxy group.

  15. Radicals derived from acetaldehyde and vinyl alcohol.

    PubMed

    Estep, Marissa L; Morgan, W James; Winkles, Alexander T; Abbott, Adam S; Villegas-Escobar, Nery; Mullinax, J Wayne; Turner, Walter E; Wang, Xiao; Turney, Justin M; Schaefer, Henry F

    2017-10-18

    Vinyl alcohol and acetaldehyde are isoelectronic products of incomplete butanol combustion. Along with the radicals resulting from the removal of atomic hydrogen or the hydroxyl radical, these species are studied here using ab initio methods as complete as coupled cluster theory with single, double, triple, and perturbative quadruple excitations [CCSDT(Q)], with basis sets as large as cc-pV5Z. The relative energies provided herein are further refined by including corrections for relativistic effects, the frozen core approximation, and the Born-Oppenheimer approximation. The effects of anharmonic zero-point vibrational energies are also treated. The syn conformer of vinyl alcohol is predicted to be lower in energy than the anti conformer by 1.1 kcal mol -1 . The alcoholic hydrogen of syn-vinyl alcohol is found to be the easiest to remove, requiring 84.4 kcal mol -1 . Five other radicals are also carefully considered, with four conformers investigated for the 1-hydroxyvinyl radical. Beyond energetics, we have conducted an overhaul of the spectroscopic literature for these species. Our results also provide predictions for fundamental modes yet to be reported experimentally. To our knowledge, the ν 3 (3076 cm -1 ) and ν 4 (2999 cm -1 ) C-H stretches for syn-vinyl alcohol and all but one of the vibrational modes for anti-vinyl alcohol (ν 1 -ν 14 ) are yet to be observed experimentally. For the acetyl radical, ν 6 (1035 cm -1 ), ν 11 (944 cm -1 ), ν 12 (97 cm -1 ), and accounting for our changes to the assignment of the 1419.9 cm -1 experimental mode, ν 10 (1441 cm -1 ), are yet to be observed. We have predicted these unobserved fundamentals and reassigned the experimental 1419.9 cm -1 frequency in the acetyl radical to ν 4 rather than to ν 10 . Our work also strongly supports reassignment of the ν 10 and ν 11 fundamentals of the vinoxy radical. We suggest that the bands assigned to the overtones of these fundamentals were in fact combination bands. Our

  16. 40 CFR 721.8658 - Modified polymer of vinyl acetate and quaternary ammonium compound (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Modified polymer of vinyl acetate and... Significant New Uses for Specific Chemical Substances § 721.8658 Modified polymer of vinyl acetate and.... (1) The chemical substance identified generically as modified polymer of vinyl acetate and quaternary...

  17. 40 CFR 721.8658 - Modified polymer of vinyl acetate and quaternary ammonium compound (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Modified polymer of vinyl acetate and... Significant New Uses for Specific Chemical Substances § 721.8658 Modified polymer of vinyl acetate and.... (1) The chemical substance identified generically as modified polymer of vinyl acetate and quaternary...

  18. 40 CFR 721.8658 - Modified polymer of vinyl acetate and quaternary ammonium compound (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Modified polymer of vinyl acetate and... Significant New Uses for Specific Chemical Substances § 721.8658 Modified polymer of vinyl acetate and.... (1) The chemical substance identified generically as modified polymer of vinyl acetate and quaternary...

  19. 40 CFR 721.8658 - Modified polymer of vinyl acetate and quaternary ammonium compound (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Modified polymer of vinyl acetate and... Significant New Uses for Specific Chemical Substances § 721.8658 Modified polymer of vinyl acetate and.... (1) The chemical substance identified generically as modified polymer of vinyl acetate and quaternary...

  20. 40 CFR 721.8658 - Modified polymer of vinyl acetate and quaternary ammonium compound (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Modified polymer of vinyl acetate and... Significant New Uses for Specific Chemical Substances § 721.8658 Modified polymer of vinyl acetate and.... (1) The chemical substance identified generically as modified polymer of vinyl acetate and quaternary...

  1. 40 CFR 721.3438 - Chlorohydroxyalkyl butyl ether (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Chlorohydroxyalkyl butyl ether... Specific Chemical Substances § 721.3438 Chlorohydroxyalkyl butyl ether (generic). (a) Chemical substance... chlorohydroxyalkyl butyl ether (PMN P-99-1295) is subject to reporting under this section for the significant new use...

  2. 40 CFR 721.3438 - Chlorohydroxyalkyl butyl ether (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Chlorohydroxyalkyl butyl ether... Specific Chemical Substances § 721.3438 Chlorohydroxyalkyl butyl ether (generic). (a) Chemical substance... chlorohydroxyalkyl butyl ether (PMN P-99-1295) is subject to reporting under this section for the significant new use...

  3. Biomedical applications of stereoregular poly(vinyl alcohol) micro- and nanoparticles

    NASA Astrophysics Data System (ADS)

    Lyoo, Won Seok; Kim, Joon Ho; Kim, Sam Soo; Ghim, Han Do

    2002-11-01

    Syndiotactic poly(vinyl alcohol) (PVA)/poly(vinyl pivalate/vinyl acetate) (P(VPi/VAc)) and atactic PVA/PVAc micro- and nanoparticles with skin/core structure have been prepared by heterogeneous saponification of P(VPi/VAc) and PVAc micro- and nanoparticles. Especially, to prepare P(VPi/VAc) and PVAc microparticles having various particle sizes and uniform particle size distribution, vinyl pivalate (VPi)/vinyl acetate (VAc) and VAc were suspension-polymerized using a low-temperature initiator, 2,2"-azobis(2,4-dimethylvaleronitrile). P(VPi/VAc) particles are promising precursor of stereoregular PVA embolic materials which can be introduced through catheters in the management of gastrointestinal bleeders, arteriovenous malformations, hemangiomas, and traumatic rupture of blood vessels. Monodisperse and/or nearly monodisperse P(VPi/VAc) and PVAc microparticles with various particle diameters were obtained by controlling suspension polymerization conditions. Monodisperse P(VPi/VAc) and PVAc microparticles having various particle sizes were partially saponified in the heterogeneous system. PVA/P(VPi/VAc) and PVA/PVAc microparticles having various tacticity and degree of saponification were produced by controlling various polymerization and saponification conditions. The coating of stereoregular PVA micro- and nanoparticles for drug release experiments was conducted with the strepo-avidin-alkaline phosphatase conjugate in variable conditions of pH value, coating buffer, and reaction temperature. Protein-coated syndiotactic PVA micro- and nanoparticles, which does not crosslinking, were more superior to controllability of drug release, durability, and dimensional stability to water and blood than atactic one.

  4. Complex Coacervate Core Micelles Containing Poly(vinyl alcohol) Inhibit Ice Recrystallization.

    PubMed

    Sproncken, Christian C M; Surís-Valls, Romà; Cingil, Hande E; Detrembleur, Christophe; Voets, Ilja K

    2018-04-10

    Complex coacervate core micelles (C3Ms) form upon complexation of oppositely charged copolymers. These co-assembled structures are widely investigated as promising building blocks for encapsulation, nanoparticle synthesis, multimodal imaging, and coating technology. Here, the impact on ice growth is investigated of C3Ms containing poly(vinyl alcohol), PVA, which is well known for its high ice recrystallization inhibition (IRI) activity. The PVA-based C3Ms are prepared upon co-assembly of poly(4-vinyl-N-methyl-pyridinium iodide) and poly(vinyl alcohol)-block-poly(acrylic acid). Their formation conditions, size, and performance as ice recrystallization inhibitors are studied. It is found that the C3Ms exhibit IRI activity at PVA monomer concentrations as low as 1 × 10 -3 m. The IRI efficacy of PVA-C3Ms is similar to that of linear PVA and PVA graft polymers, underlining the influence of vinyl alcohol monomer concentration rather than polymer architecture. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Plug Repairs of Marine Glass Fiber / Vinyl Ester Laminates Subjected to Uniaxial Tension

    DTIC Science & Technology

    2009-06-01

    Material characteristics of glass fiber / vinyl ester composites used in naval surface ships 1.1.1.2 Construction of surface ship hulls with FRP...Piping - Ventilation ducts - Deck gratings 1.1.1.1 Material characteristics of glass fiber / vinyl ester composites used in naval surface ships The...that polysester-based composites do [15, 24]. Typical processing methods for vinyl ester composites are hand lay-up, Resin Transfer Molding (RTM

  6. Specific adhesion model for bonding hot-melt polyamides to vinyl

    Treesearch

    Charles R. Frihart

    2004-01-01

    Hot-melt polyamides are an important market for the dimer acid made from the tall oil fatty acids liberated during the Kraft pulping process. These polyamides bond well to many substrates, but not to polyvinyl chloride (PVC), commonly called vinyl. Dimer-based polyamides made from secondary amines such as piperazine bond well to vinyl. No model for this unique adhesion...

  7. 21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot.... Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also...

  8. 21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot.... Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also...

  9. 21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot.... Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also...

  10. 21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot.... Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also...

  11. 21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... of the flask at 150 °F for 2 hours using a hot plate while also maintaining gentle mechanical agitation. Filter the contents of the flask rapidly through No. 42 Whatman filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot plate and evaporate the...

  12. Poly (N-ethyl aniline)/Ag Nanocomposite as Humidity Sensor

    NASA Astrophysics Data System (ADS)

    Pande, Nishigandh S.; Jaspal, Dipika; Ambekar, Jalindar

    Poly (N-ethyl aniline)/Ag organic-inorganic composite has been synthesized by a single step in situ chemical oxidative polymerization method. The synthesis of Poly (N-ethyl aniline)/Ag nanocomposite has been confirmed by X-ray diffraction (XRD), Ultraviolet-Vis Spectroscopy (UV-visible), Fourier transform infrared analysis (FTIR) and FE-SEM investigations. XRD spectral study exhibited major diffraction in the range 20-80∘ (2θ) and indicated the semicrystalline nature of poly (N-ethyl aniline)/Ag nanocomposite. Characteristic peaks in UV-visible and FTIR spectra of poly (N-ethyl aniline) switched to higher wave numbers in poly (N-ethyl aniline)/Ag nanocomposite. Peaks at 1789cm-1, 1595cm-1, 667cm-1 and 501cm-1 in FTIR spectrum confirmed the formation of poly (N-ethyl aniline)/Ag nanocomposite. FE-SEM photographs reported agglomerated granular particulate nature of poly (N-ethyl aniline)/Ag nanocomposite. Synthesized poly (N-ethyl aniline)/Ag nanocomposite exhibited a high response to humidity, good reproducibility and stability at room temperature. An appreciable response was shown in the presence of 40% humid atmosphere for up to successive four cycles. Composite sensitivity has been found to increase with the increasing concentration of humidity, at room temperature.

  13. The Vinyl Acetate Content of Packaging Film: A Quantitative Infrared Experiment.

    ERIC Educational Resources Information Center

    Allpress, K. N.; And Others

    1981-01-01

    Presents an experiment used in laboratory technician training courses to illustrate the quantitative use of infrared spectroscopy which is based on industrial and laboratory procedures for the determination of vinyl acetate levels in ethylene vinyl acetate packaging films. Includes three approaches to allow for varying path lengths (film…

  14. Do occupational exposures to vinyl chloride cause hepatocellular carcinoma and cirrhosis?

    PubMed

    Lotti, Marcello

    2017-05-01

    Controversy exists about the association between occupational exposures to vinyl chloride and hepatocellular carcinoma and cirrhosis. Two large multicentre mortality cohort studies, one American and another European, reported higher mortality for primary cancer of liver and biliary tract. However, the American study was not able to rule out misclassification, because based on death certificates and under the heading primary liver cancers, some angiosarcomas, the typical neoplasia associated with vinyl chloride, may have been included. The American study does not report on cirrhosis mortality. The European study also reports higher mortality of primary liver cancer, but contrary to the American study in a further analysis based on 10 verified cases of hepatocellular carcinoma, an exposure-response trend with duration of employment and with cumulative exposure to vinyl chloride was detected. A smaller cohort belonging to this multicentre cohort confirmed these results. Meta-analyses based on the two large cohorts concluded for a small excess of primary liver cancer, although misclassification could not be ruled out. Excess risk of cirrhosis was reported in the European cohort, in a subcohort and in a cross-sectional study. However, a meta-analysis did not confirm this excess. Several critical appraisals of the literature reached antithetical conclusions about hepatocellular carcinoma, cirrhosis and occupational exposures to vinyl chloride. For both hepatocellular carcinoma and cirrhosis, a study suggests an additive and multiplicative effect of vinyl chloride exposure with viral hepatitis and alcohol consumption respectively. Pathology reports seem to indicate a possible development of hepatocellular carcinoma but not of cirrhosis after high exposures to vinyl chloride. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Chemoselective Deprotection of Triethylsilyl Ethers

    PubMed Central

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

    2009-01-01

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

  16. 75 FR 42311 - Third Party Testing for Certain Children's Products; Vinyl Plastic Film: Requirements for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-21

    ... Testing for Certain Children's Products; Vinyl Plastic Film: Requirements for Accreditation of Third Party... relating to vinyl plastic film. The Commission is issuing this notice of requirements pursuant to the.... Comments should be captioned ``Third Party Testing for Certain Children's Products; Vinyl Plastic Film...

  17. Tribromodiphenyl ether

    Integrated Risk Information System (IRIS)

    Tribromodiphenyl ether ; CASRN 49690 - 94 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarci

  18. Octabromodiphenyl ether

    Integrated Risk Information System (IRIS)

    Octabromodiphenyl ether ; CASRN 32536 - 52 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarc

  19. Nonabromodiphenyl ether

    Integrated Risk Information System (IRIS)

    Nonabromodiphenyl ether ; CASRN 63936 - 56 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarc

  20. Hexabromodiphenyl ether

    Integrated Risk Information System (IRIS)

    Hexabromodiphenyl ether ; CASRN 36483 - 60 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarc

  1. Pentabromodiphenyl ether

    Integrated Risk Information System (IRIS)

    Pentabromodiphenyl ether ; CASRN 32534 - 81 - 9 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncar

  2. Tetrabromodiphenyl ether

    Integrated Risk Information System (IRIS)

    Tetrabromodiphenyl ether ; CASRN 40088 - 47 - 9 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncar

  3. Synthesis of Enantiopure Alicyclic Ethers and Their Activity on the Chemosensory Organ of the Ectoparasite of Honey Bees, Varroa destructor.

    PubMed

    Pinnelli, Govardhana R; Singh, Nitin K; Soroker, Victoria; Plettner, Erika

    2016-11-16

    The preparation of enantiopure conformationally restricted alicyclic ethers and their inhibitory activities on the chemosensory organ of the Varroa destructor, a parasite of honey bees, are reported in this article. We tested the effect of enantiopure ethers of cis-5-(2'-hydroxyethyl)cyclopent-2-en-1-ol on the Varroa chemosensory organ by electrophysiology, for their ability to inhibit the responses to two honey bee-produced odors that are important for the mite to locate its host: nurse bee head space odor and (E)-β-ocimene, a honey bee brood pheromone. Previous work with the racemic compounds showed that they suppress the mite's olfactory response to its bee host, which led to incorrect host choice. Based on a structure-activity relationship, we predicted that the two most active compounds-cis-1-butoxy-5-(2'-methoxyethyl)cyclopent-2-ene, cy{4,1}, and (cis-1-ethoxy-5-(2'ethoxyethyl)cyclopent-2-ene, cy{2,2}-could have opposite active enantiomers. Here we studied the enantiomers of both ethers, whose preparation involved enzymatic resolution of racemic diol cis-5-(2'-hydroxyethyl)cyclopent-2-en-1-ol using Lipase AK with vinyl acetate. The racemic diol was prepared from commercially available 2,5-norbornadiene. We observed that the responses of the chemosensory organ to honey bee head space volatiles were significantly decreased by both enantiomers of cy{4,1} and cy{2,2}, but that responses to (E)-β-ocimene were decreased significantly only by (+)-cy{4,1} (1R,5S) and (-)-cy{2,2} (1S,5R) and not by their respective enantiomers. The importance of this result is that the racemates could be used to inhibit olfactory detection of bee odors by mites, without a loss in activity relative to the more expensive enantiopure compounds.

  4. 21 CFR 184.1295 - Ethyl formate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...)(22) of this chapter; and 0.01 percent in all other food categories. (e) Prior sanctions for ethyl... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethyl formate. 184.1295 Section 184.1295 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

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

    PubMed

    Hintzenstern, U v; Schwarz, W

    1996-02-01

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

  6. Permeation enhancement via thiolation: in vitro and ex vivo evaluation of hyaluronic acid-cysteine ethyl ester.

    PubMed

    Laffleur, Flavia; Psenner, Julia; Suchaoin, Wongsakorn

    2015-07-01

    It was the aim of this study to evaluate the permeation-enhancing effect of synthesized thiolated hyaluronic acid (HA). HA, a naturally found polysaccharide, was chemically modified with l-cysteine ethyl ether (C) via amide bond formation. In vitro permeation enhancement was tested on Caco-2 cells with two compounds, sulforhodamine (SR) and fluorescein isothiocyanate-dextran (FD4). Cytotoxicity assays as lactate dehydrogenase and thiazolyl blue tetrazolium bromide (MTT) were performed on colon carcinoma cell line. Transepithelial electrical resistance (TEER) measurements were conducted. Ex vivo evaluation was accomplished on rat intestinal mucosa in order to predict the permeation enhancing effect with SR, sodium fluorescein (SF), and FD4, respectively. The MTT as well as lactate dehydrogenase revealed no toxicity over time periods of 3 and 12 h, respectively. The bioconjugate is biocompatible and safe to use. Furthermore, TEER measurements showed the integrity of tight junctions. The in vitro permeation studies on cell studies exhibit 1.28-fold enhancement for SR and 1.47-fold enhancement for FD4 with hyaluronic acid-cysteine ethyl ester (HAC) in comparison to unmodified one. The ex vivo transport studies exhibit 1.9-fold enhancement for SF, 1.31-fold enhancement for Rhodamine123, and 1.3-fold enhancement for FD4 with HAC in comparison to unmodified one, respectively. Thus, the promising results encourage further investigations and exploitation of this versatile polysaccharide. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  7. 21 CFR 73.3127 - Vinyl alcohol/methyl methacrylate-dye reaction products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Vinyl alcohol/methyl methacrylate-dye reaction... Vinyl alcohol/methyl methacrylate-dye reaction products. (a) Identity. The color additives are formed by... methacrylate-dye reaction product listed under this section into commerce shall submit to the Food and Drug...

  8. 21 CFR 73.3127 - Vinyl alcohol/methyl methacrylate-dye reaction products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Vinyl alcohol/methyl methacrylate-dye reaction... Vinyl alcohol/methyl methacrylate-dye reaction products. (a) Identity. The color additives are formed by... methacrylate-dye reaction product listed under this section into commerce shall submit to the Food and Drug...

  9. H sub 3 PMo sub 12 O sub 40 -doped polyacetylene as a catalyst for ethyl alcohol conversion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pozniczek, J.; Bielanski, A.; Kulszewicz-Bajer, I.

    1991-12-01

    A new and highly efficient catalyst was obtained by exploiting the unique ability of polyacetylene to incorporate heteropolyanions (HPA) of the Keggin type via oxidative doping. 12-Molybdophosphoric acid, 20.8 wt%, was introduced into the polymer. A uniform distribution of HPA over the cross section of the polymer film was found. However, the concentration of HPA seemed to be higher at the surface of the polymer fibers than in their bulk. The conversion of ethyl alcohol was used as a catalytic test reaction. The catalyst exhibited both acid-base activity (formation of ethylene and diethyl ether) as well as redox activity (formationmore » of acetaldehyde). The acid-base activity was 10 times higher than that of unsupported H{sub 3}PMo{sub 12}O{sub 40}, and the redox activity was about 40 times higher.« less

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

    NASA Astrophysics Data System (ADS)

    Li, Lijie; Cocker, David R.

    2018-05-01

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

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Meng; Gutiérrez, Oliver Y.; Camaioni, Donald M.

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

  12. 76 FR 63282 - Foreign-Trade Zone 140-Flint, Michigan; Application for Subzone; Dow Corning Corporation (Silicon...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-12

    ..., allylglycol, allyl glycidyl ether, methyl ethyl ketone, diacetone alcohol, octanoic acid, undecylenic acid, monoplex dos, ethyl silicate, sparc base, dimethylethanolamine, vinyltriacetoxysilane, dimethyl me...

  13. Process for the preparation of ethyl benzene

    DOEpatents

    Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

    1995-12-19

    Ethyl benzene is produced in a catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 50 C to 300 C, using as the catalyst a mole sieve characterized as acidic by feeding ethylene to the catalyst bed while benzene is conveniently added through the reflux to result in a molar excess present in the reactor to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene and diethyl benzene in the bottoms. The bottoms are fractionated, the ethyl benzene recovered and the bottoms are contacted with benzene in the liquid phase in a fixed bed straight pass reactor under conditions to transalkylate the benzene thereby converting most of the diethyl benzene to ethyl benzene which is again separated and recovered. 2 figs.

  14. Process for the preparation of ethyl benzene

    DOEpatents

    Smith, Jr., Lawrence A.; Arganbright, Robert P.; Hearn, Dennis

    1995-01-01

    Ethyl benzene is produced in a catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 50.degree. C. to 300.degree. C., using as the catalyst a mole sieve characterized as acidic by feeding ethylene to the catalyst bed while benzene is conveniently added through the reflux to result in a molar excess present in the reactor to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene and diethyl benzene in the bottoms. The bottoms are fractionated, the ethyl benzene recovered and the bottoms are contacted with benzene in the liquid phase in a fixed bed straight pass reactor under conditions to transalkylate the benzene thereby converting most of the diethyl benzene to ethyl benzene which is again separated and recovered.

  15. 40 CFR 180.441 - Quizalofop ethyl; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... residues of the herbicide quizalofop ethyl, including its metabolites and degradates, in or on the....05 (2) Tolerances are established for residues of the herbicide quizalofop ethyl, including its... the herbicide quizalofop ethyl, including its metabolites and degradates, in or on the commodities in...

  16. 40 CFR 180.441 - Quizalofop ethyl; tolerances for residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... residues of the herbicide quizalofop ethyl, including its metabolites and degradates, in or on the....05 (2) Tolerances are established for residues of the herbicide quizalofop ethyl, including its... the herbicide quizalofop ethyl, including its metabolites and degradates, in or on the commodities in...

  17. 40 CFR 180.441 - Quizalofop ethyl; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... residues of the herbicide quizalofop ethyl, including its metabolites and degradates, in or on the....05 (2) Tolerances are established for residues of the herbicide quizalofop ethyl, including its... the herbicide quizalofop ethyl, including its metabolites and degradates, in or on the commodities in...

  18. Effect of gamma ray on poly(lactic acid)/poly(vinyl acetate-co-vinyl alcohol) blends as biodegradable food packaging films

    NASA Astrophysics Data System (ADS)

    Razavi, Seyed Mohammad; Dadbin, Susan; Frounchi, Masoud

    2014-03-01

    Poly(lactic acid) (PLA)/poly(vinyl acetate-co-vinyl alcohol) [P(VAc-co-VA)] blends as new transparent film packaging materials were prepared at various blend compositions and different vinyl alcohol contents. The blends and pure PLA were irradiated by gamma rays to investigate the extent of changes in the packaging material during gamma ray sterilization process. The miscibility of the blends was dependent on the blend composition and vinyl alcohol content; gamma irradiation had little effect on the extent of miscibility. The glass transition temperature of pure PLA and PLA/P(VAc-co-VA) miscible blends reduced after irradiation. On the other hand in PLA/P(VAc-co-VA) immiscible blends, while the glass transition temperature of the PLA phase decreased; that of the copolymer phase slightly increased. The reduction in the glass transition was about 10 percent for samples irradiated with 50 kGy indicating dominance of chain scission of PLA molecules at high irradiation dose. The latter was verified by drop in mechanical properties of pure PLA after exposing to gamma irradiation at 50 kGy. Blending of PLA with the copolymer P(VAc-co-VA) compensated greatly the adverse effects of irradiation on PLA. The oxygen-barrier property of the blend was superior to the neat PLA and remained almost intact with irradiation. The un-irradiated and irradiated blends had excellent transparency. Gamma ray doses used for sterilization purposes are usually less than 20 kGy. It was shown that gamma irradiation at 20 kGy had no or little adverse effects on PLA/P(VAc-co-VA) blends mechanical and gas barrier properties.

  19. Phenylethynl-terminated poly(arylene ethers)

    NASA Technical Reports Server (NTRS)

    Jensen, Brian J. (Inventor); Bryant, Robert G. (Inventor); Hergenrother, Paul M. (Inventor)

    1993-01-01

    Phenylethynyl-terminated poly(arylene ethers) are prepared in a wide range of molecular weights by adjusting monomer ratio and adding an appropriate amount of 4-fluoro- 4'-phenylethynyl benzophenone during polymer synthesis. The resulting phenylethynyl-terminated poly(arylene ethers) react and crosslink upon curing for one hour at 350 C to provide materials with improved solvent resistance, higher modulus, and better high temperature properties than the linear, uncrosslinked polymers.

  20. Microwave spectroscopy and curious molecular dynamics of ethyl trifluoroacetate

    NASA Astrophysics Data System (ADS)

    Bohn, Robert K.; Montgomery, John A.; Harvey Michels, H.; Acharte, Christian

    2017-05-01

    The first ethyl ester whose structure was determined by microwave spectroscopy is ethyl formate. It exists in two conformations. In the 1970s, that study was used as a model to determine the structures of other ethyl esters, ethyl cyanoformate, chloroformate, and trifluoroacetate. They display the same conformations as ethyl formate. But under the experimental conditions used, Stark modulation with a maximum electric field, static low pressure gas, rapid sweeping, and long detector time constants, each of those esters displays bands of an additional third species. A careful, high resolution study of ethyl cyanoformate only observed two conformers. A model has been proposed that the third species derives from a dense array of torsionally excited states with broadened transitions due to short lifetimes. The present study of ethyl trifluoroacetate in a pulsed jet Fourier Transform spectrometer is intended to clarify the earlier results. Two conformers are observed including all their monosubstituted 13C and 18O isotopologs. In a pulsed jet Fourier Transform spectrometer using argon as the carrier gas, only one conformer is observed. Switching to helium as the carrier gas, another, higher energy conformer is also observed.

  1. Synthesis and characterization of poly(vinyl alcohol) membranes with quaternary ammonium groups for wound dressing.

    PubMed

    Chen, Kuo-Yu; Lin, Yu-Sheng; Yao, Chun-Hsu; Li, Ming-Hsien; Lin, Jui-Che

    2010-01-01

    2-[(acryloyloxy)ethyl]Trimethylammonium chloride (AETMAC) was grafted onto poly(vinyl alcohol) (PVA) using ceric ammonium nitrate (CAN) as a redox initiator. A series of graft co-polymer (PVA-g-PAETMAC) membranes with different contents of AETMAC were prepared with a casting method. The incorporation of AETMAC into PVA chains was confirmed by element analysis and Fourier transform infrared spectroscopy. The effects of grafting on the thermal properties, water take, water vapor transmission rate (WVTR), contact angle, antibacterial activity and cytotoxicity of PVA-g-PAETMAC membranes were investigated. The experiment results showed that PVA-g-PAETMAC membrane has a higher equilibrium swelling ratio, surface hydrophilicity and WVTR than pure PVA membrane. Moreover, the higher the content of AETMAC, the higher were equilibrium swelling ratio, surface hydrophilicity and WVTR. In vitro bacterial adhesion study demonstrated a significantly reduced number of Staphylococcus aureus and Escherichia coli on PVA-g-PAETMAC surfaces when compared to PVA surface. In addition, no significant difference in the in vitro cytotoxicity was observed between PVA and PVA-g-PAETMAC membranes. The presence of quaternary ammonium groups did not reduce L929 cell growth. Therefore, the PVA-g-PAETMAC membranes have the potential for wound-dressing application.

  2. Alkyl Aryl Ether Bond Formation with PhenoFluor**

    PubMed Central

    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. PMID:25800679

  3. New derivatives of 11-methyl-6-[2-(dimethylamino)ethyl]-6H-indolo[2,3-b]quinoline as cytotoxic DNA topoisomerase II inhibitors.

    PubMed

    Luniewski, Wojciech; Wietrzyk, Joanna; Godlewska, Joanna; Switalska, Marta; Piskozub, Malgorzata; Peczynska-Czoch, Wanda; Kaczmarek, Lukasz

    2012-10-01

    Novel indolo[2,3-b]quinoline derivatives substituted at N-6 and C-2 or C-9 positions with (dimethylamino)ethyl chains linked to heteroaromatic core by ether, amide or amine bonds, were manufactured and evaluated in vitro for their cytotoxic activity against several cell lines of different origin including multidrug resistant sublines and tested for their ability to influence the cell cycle and inhibit topoisomerase II activity. It was found, that all compounds show cytotoxic activity against cell lines tested, including multidrug resistant LoVo/DX, MES-SA/DX5 and HL-60 sublines. The tested compounds induce the G(2)M phase cell cycle arrest in Jurkat cells, and inhibit topoisomerase II activity. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Merging photoredox and nickel catalysis: decarboxylative cross-coupling of carboxylic acids with vinyl halides.

    PubMed

    Noble, Adam; McCarver, Stefan J; MacMillan, David W C

    2015-01-21

    Decarboxylative cross-coupling of alkyl carboxylic acids with vinyl halides has been accomplished through the synergistic merger of photoredox and nickel catalysis. This new methodology has been successfully applied to a variety of α-oxy and α-amino acids, as well as simple hydrocarbon-substituted acids. Diverse vinyl iodides and bromides give rise to vinylation products in high efficiency under mild, operationally simple reaction conditions.

  5. Merging Photoredox and Nickel Catalysis: Decarboxylative Cross-Coupling of Carboxylic Acids with Vinyl Halides

    PubMed Central

    2015-01-01

    Decarboxylative cross-coupling of alkyl carboxylic acids with vinyl halides has been accomplished through the synergistic merger of photoredox and nickel catalysis. This new methodology has been successfully applied to a variety of α-oxy and α-amino acids, as well as simple hydrocarbon-substituted acids. Diverse vinyl iodides and bromides give rise to vinylation products in high efficiency under mild, operationally simple reaction conditions. PMID:25521443

  6. Enantioselective α-Vinylation of Aldehydes Via the Synergistic Combination of Copper and Amine Catalysis

    PubMed Central

    Skucas, Eduardas; MacMillan, David W. C.

    2012-01-01

    The enantioselective α-vinylation of aldehydes using vinyl iodonium triflate salts has been accomplished via the synergistic combination of copper and chiral amine catalysis. These mild catalytic conditions provide a direct route for the enantioselective construction of enolizable α-formyl vinylic stereocenters without racemization or olefin transposition. These high-value coupling adducts are readily converted into a variety of useful olefin synthons. PMID:22616631

  7. 40 CFR 180.430 - Fenoxaprop-ethyl; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... residues of the herbicide fenoxaprop-ethyl, including its metabolites and degradates, in or on the... for residues of the herbicide fenoxaprop-ethyl, including its metabolites and degradates, in or on the... registration, as defined in § 180.1(l), are established for residues of the herbicide fenoxaprop-ethyl...

  8. Novel alkyd-type coating resins produced using cationic polymerization

    DOE PAGES

    Chisholm, Bret J.; Kalita, Harjyoti; Alam, Samim; ...

    2015-05-06

    Novel, partially bio-based poly(vinyl ether) copolymers derived from soybean oil and cyclohexyl vinyl ether (CHVE) were produced by cationic polymerization and investigated for application as alkyd-type surface coatings. Compared to conventional alkyd resins, which are produced by high temperature melt condensation polymerization, the poly(v9nyl ether)s provide several advantages. These advantages include milder, more energy efficient polymer synthesis, elimination of issues associated with gelation during polymer synthesis, production of polymers with well-defined composition and relatively narrow molecular weight distribution, and elimination of film formation and physical property issues associated with entrained monomers, dimers, trimers, etc. The results of the studied showedmore » that the thermal, mechanical, and physical properties of the coatings produced from these novel polymers varied considerably as a function of polymer composition and cure temperature. Overall, the results suggest a good potential for these novel copolymers to be used for coatings cured by autoxidation.« less

  9. Preparation and Characterization of Various Poly(ether ether ketone) Containing Imidazolium Moiety for Anion Exchange Membrane Fuel Cell Application.

    PubMed

    Lee, Byeol-Nim; Son, Tae Yang; Park, Chi Hoon; Kim, Tae Hyun; Nam, Sang Yong

    2018-09-01

    In this study, various poly(ether ether ketone) were synthesized using three different monomers and the imidazolium group was introduced into synthesized poly(ether ether ketone)s by using substitution reaction. Synthesized polymers were used to prepare anion exchange membranes and to evaluate its properties. Thermal, chemical and structural properties were carried out using thermogravimetric analysis, nuclear magnetic resonance. The anion exchange membranes with different imidazolium moieties were characterized by several different analytical techniques such as water up take, ion exchange capacity, hydroxide conductivity for checking the possibility to apply the anion exchange membrane fuel cell. Consequently, results of characterization were studied to understand the correlation between stabilities of the membrane and functional group and polymer backbone structures. And we confirm membrane performance was improved by increasing imidazolium cation groups.

  10. Highly filled biocomposites based on ethylene-vinyl acetate copolymer and wood flour

    NASA Astrophysics Data System (ADS)

    Shelenkov, P. G.; Pantyukhov, P. V.; Popov, A. A.

    2018-05-01

    Recently, there is a great interest in the world to biodegradable materials based on synthetic polymers in a composition with natural fillers. Highly filled polymer composite materials based on various grades of synthetic block copolymer of ethylene vinyl acetate with wood flour were under investigation. Five grades of ethylene-vinyl acetate copolymer differing in the content of vinyl acetate groups and a melt flow index were used in this work in order to find the best one for highly filled biocomposites. Wood flour content in biocomposites was 50, 60, 70 weight %. The rheological and physico-mechanical characteristics of the resulting biocomposites were studied.

  11. [Growth inhibition of the four species of red tide microalgae by extracts from Enteromorpha prolifera extracted with the five solvents].

    PubMed

    Sun, Ying-Ying; Liu, Xiao-Xiao; Wang, Chang-Hai

    2010-06-01

    To study the effects of extracts of Enteromorpha prolifera on the growth of the four species of red tide microalgae (Amphidinium hoefleri, Karenia mikimitoi, Alexandrium tamarense and Skeletonema costatum), the extracts were extracted with five solvents (methanol, acetone, ethyl acetate, chloroform and petroleum ether), respectively. Based on the observation of algal morphology and the measurement of algal density, cell size and the contents of physiological indicators (chlorophyll, protein and polysaccharide), the results showed methanol extracts of E. prolifera had the strongest action. The inhibitory effects of A. hoefleri, K. mikimitoi, A. tamarense and S. costatum by the methanol extracts were 54.0%, 48.1%, 44.0% and 37.5% in day 10, respectively. The extracts of E. prolifera extracted with methanol, acetone and ethyl acetate caused cavities, pieces and pigment reduction in cells, and those with chloroform and petroleum ether caused goffers on cells. The extracts of E. prolifera extracted with all the five solvents decreased athletic ability of the cells, among which those extracted with ethyl acetate, chloroform and petroleum ether decreased cell size of test microalgae. The further investigation found that the methanol extracts significantly decreased contents of chlorophyll, protein and polysaccharide in the cells of those microalgae. The inhibitory effect of chlorophyll, protein and polysaccharide contents of four species of microalgae by the methanol extracts was about 51%. On the basis of the above experiments, dry powder of E. prolifera were extracts with methanol, and extracts were obtained. The methanol extracts were partitioned to petroleum ether phase, ethyl acetate phase, n-butanol phase and distilled water phase by liquid-liquid fractionation, and those with petroleum ether and ethyl acetate significantly inhibited the growth of all test microalgae, and the inhibitory effect of four species of microalgae by those two extracts was above 25% in day

  12. Interstellar Aldehydes and their corresponding Reduced Alcohols: Interstellar Propanol?

    NASA Astrophysics Data System (ADS)

    Etim, Emmanuel; Chakrabarti, Sandip Kumar; Das, Ankan; Gorai, Prasanta; Arunan, Elangannan

    2016-07-01

    There is a well-defined trend of aldehydes and their corresponding reduced alcohols among the known interstellar molecules; methanal (CH_2O) and methanol (CH_3OH); ethenone (C_2H_2O) and vinyl alcohol (CH_2CHOH); ethanal (C_2H_4O) and ethanol(C_2H_5OH); glycolaldehyde (C_2H_4O_2) and ethylene glycol(C_2H_6O_2). The reduced alcohol of propanal (CH_3CH_2CHO) which is propanol (CH_3CH_2CH_2OH) has not yet been observed but its isomer; ethyl methyl ether (CH_3CH_2OCH_3) is a known interstellar molecule. In this article, different studies are carried out in investigating the trend between aldehydes and their corresponding reduced alcohols and the deviation from the trend. Kinetically and with respect to the formation route, alcohols could have been produced from their corresponding reduced aldehydes via two successive hydrogen additions. This is plausible because of (a) the unquestionable high abundance of hydrogen, (b) presence of energy sources within some of the molecular clouds and (c) the ease at which successive hydrogen addition reaction occurs. In terms of stability, the observed alcohols are thermodynamically favorable as compared to their isomers. Regarding the formation process, the hydrogen addition reactions are believed to proceed on the surface of the interstellar grains which leads to the effect of interstellar hydrogen bonding. From the studies, propanol and propan-2-ol are found to be more strongly attached to the surface of the interstellar dust grains which affects its overall gas phase abundance as compared to its isomer ethyl methyl ether which has been observed.

  13. Gas chromatography-mass spectrometry of ethyl palmitate calibration and resolution with ethyl oleate as biomarker ethanol sub acute in urine application study

    NASA Astrophysics Data System (ADS)

    Suaniti, Ni Made; Manurung, Manuntun

    2016-03-01

    Gas Chromatography-Mass Spectrometry is used to separate two and more compounds and identify fragment ion specific of biomarker ethanol such as palmitic acid ethyl ester (PAEE), as one of the fatty acid ethyl esters as early detection through conyugated reaction. This study aims to calibrate ethyl palmitate and develop analysis with oleate acid. This methode can be used analysis ethanol and its chemistry biomarker in ethanol sub-acute consumption as analytical forensic toxicology. The result show that ethanol level in urine rats Wistar were 9.21 and decreased 6.59 ppm after 48 hours consumption. Calibration curve of ethyl palmitate was y = 0.2035 x + 1.0465 and R2 = 0.9886. Resolution between ethyl palmitate and oleate were >1.5 as good separation with fragment ion specific was 88 and the retention time was 18 minutes.

  14. Gas Chromatographic Separation of an Acetylene Vinyl Fluoride-Difluoroethane Mixture on Triethylene Glycol and Silicone Oil,

    DTIC Science & Technology

    The purpose of the research was to study gas-chromatographic separation of impurities of acetylene and difluoroethane in vinyl fluoride obtained by...and difluoroethane . All the components are separated, and the criteria of separation of acetylene-vinyl fluoride and vinyl fluoride- difluoroethane

  15. 29 CFR 1910.1017 - Vinyl chloride.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...: Cancer; central nervous system effects; liver effects; blood effects; and flammability. (iii) Employers..., whichever occurs first. (B) A continuous-monitoring and alarm system must be provided when concentrations of... system must be used to alert employees when vinyl chloride concentrations exceed the allowable...

  16. 29 CFR 1910.1017 - Vinyl chloride.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...: Cancer; central nervous system effects; liver effects; blood effects; and flammability. (iii) Employers..., whichever occurs first. (B) A continuous-monitoring and alarm system must be provided when concentrations of... system must be used to alert employees when vinyl chloride concentrations exceed the allowable...

  17. 29 CFR 1910.1017 - Vinyl chloride.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...: Cancer; central nervous system effects; liver effects; blood effects; and flammability. (iii) Employers..., whichever occurs first. (B) A continuous-monitoring and alarm system must be provided when concentrations of... system must be used to alert employees when vinyl chloride concentrations exceed the allowable...

  18. Kinetics of acyl transfer reactions in organic media catalysed by Candida antarctica lipase B.

    PubMed

    Martinelle, M; Hult, K

    1995-09-06

    The acyl transfer reactions catalysed by Candida antartica lipase B in organic media followed a bi-bi ping-pong mechanism, with competitive substrate inhibition by the alcohols used as acyl acceptors. The effect of organic solvents on Vm and Km was investigated. The Vm values in acetonitrile was 40-50% of those in heptane. High Km values in acetonitrile compared to those in heptane could partly be explained by an increased solvation of the substrates in acetonitrile. Substrate solvation caused a 10-fold change in substrate specificity, defined as (Vm/Km)ethyl octanoate/(Vm/Km)octanoic acid, going from heptane to acetonitrile. Deacylation was the rate determining step for the acyl transfer in heptane with vinyl- and ethyl octanoate as acyl donors and (R)-2-octanol as acyl acceptor. With 1-octanol, a rate determining deacylation step in heptane was indicated using the same acyl donors. Using 1-octanol as acceptor in heptane, S-ethyl thiooctanoate had a 25- to 30-fold lower Vm/Km value and vinyl octanoate a 4-fold higher Vm/Km value than that for ethyl octanoate. The difference showed to be a Km effect for vinyl octanoate and mainly a Km effect for S-ethyl thiooctanoate. The Vm values of the esterification of octanoic acid with different alcohols was 10-30-times lower than those for the corresponding transesterification of ethyl octanoate. The low activity could be explained by a low pH around the enzyme caused by the acid or a withdrawing of active enzyme by nonproductive binding by the acid.

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

    PubMed

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

    2018-03-01

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

  20. 40 CFR 433.11 - Specialized definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-chloroisopropyl) ether Bis (2-chloroethoxy) methane Methylene chloride (dichloromethane) Methyl chloride...-phenlene pyrene) Pyrene Tetrachloroethylene Toluene Trichloroethylene Vinyl chloride (chloroethylene...

  1. Reusable recording medium based on MBPVA and vinyl acetate

    NASA Astrophysics Data System (ADS)

    John, Beena Mary; Ushamani, M.; Joseph, Rani; Sreekumar, K.; Sudha Kartha, C.

    2006-03-01

    A new photopolymerizable recording media is introduced based on poly (vinyl alcohol) and vinyl acetate sensitized with methylene blue. It is observed that this MBPVA/VAc system can be reused a number of times without significant decrease in diffraction efficiency. The PVA-VAc ratio was optimized at 2:1. Diffraction efficiency of 6.3% was obtained without any fixing at a dye concentration of 9.3?×?10-4?mol/l at an exposure of 750?mJ/cm2. The material is attractive on account of its reusability.

  2. 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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kakehashi, Anna, E-mail: anna@med.osaka-cu.ac.jp; Hagiwara, Akihiro; Imai, Norio

    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 downregulationmore » 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.« less

  3. Palladium-catalyzed stereoretentive olefination of unactivated C(sp3)-H bonds with vinyl iodides at room temperature: synthesis of β-vinyl α-amino acids.

    PubMed

    Wang, Bo; Lu, Chengxi; Zhang, Shu-Yu; He, Gang; Nack, William A; Chen, Gong

    2014-12-05

    A method is reported for palladium-catalyzed N-quinolyl carboxamide-directed olefination of the unactivated C(sp(3))-H bonds of phthaloyl alanine with a broad range of vinyl iodides at room temperature. This reaction represents the first example of the stereoretentive installation of multisubstituted terminal and internal olefins onto unactivated C(sp(3))-H bonds. These methods enable access to a wide range of challenging β-vinyl α-amino acid products in a streamlined and controllable fashion, beginning from simple precursors.

  4. Functionalized poly(arylene ethers) as toughness modifiers for bismaleimides

    NASA Technical Reports Server (NTRS)

    Stenzenberger, H. D.; Roemer, W.; Hergenrother, P. M.; Jensen, B.; Breitigam, W.

    1990-01-01

    A family of novel, low molecular weight functionalized poly(arylene ether) resins has been investigated to ascertain its members' toughness-imparting contribution to neat bismaleimide (BMI) resin and BMI-matrix laminate composite properties. Attention is given to the contribution of the reactive poly(arylene ether)'s backbone chemistry to fracture toughness, as well as to the comparative influence of high and low molecular weight reactive poly(arylene ether) types on the modified BMI resin systems. The modified BMIs possess a polyphase morphology, with good adhesion between the thermoplastic nodules and the host thermoset systems.

  5. Icosapent ethyl (eicosapentaenoic acid ethyl ester): Effects on remnant-like particle cholesterol from the MARINE and ANCHOR studies.

    PubMed

    Ballantyne, Christie M; Bays, Harold E; Philip, Sephy; Doyle, Ralph T; Braeckman, Rene A; Stirtan, William G; Soni, Paresh N; Juliano, Rebecca A

    2016-10-01

    Remnant-like particle cholesterol (RLP-C) is atherogenic and may increase atherosclerotic cardiovascular disease risk. Icosapent ethyl is a high-purity prescription eicosapentaenoic acid ethyl ester (approved as an adjunct to diet to reduce triglyceride [TG] levels in adult patients with TGs ≥500 mg/dL [≥5.65 mmol/L] at 4 g/day). In the MARINE and ANCHOR studies, icosapent ethyl reduced TG and other atherogenic lipid parameter levels without increasing low-density lipoprotein cholesterol (LDL-C) levels. This exploratory analysis evaluated the effects of icosapent ethyl on calculated and directly measured RLP-C. MARINE (TGs ≥500 and ≤2000 mg/dL [≥5.65 mmol/L and ≤22.6 mmol/L]) and ANCHOR (TGs ≥200 and <500 mg/dL [≥2.26 and <5.65 mmol/L] despite statin-controlled LDL-C) were phase 3, 12-week, double-blind studies that randomized adult patients to icosapent ethyl 4 g/day, 2 g/day, or placebo. This analysis assessed median percent change from baseline to study end in directly measured (immunoseparation assay) RLP-C levels (MARINE, n = 218; ANCHOR, n = 252) and calculated RLP-C levels in the full populations. Icosapent ethyl 4 g/day significantly reduced directly measured RLP-C levels -29.8% (p = 0.004) in MARINE and -25.8% (p = 0.0001) in ANCHOR versus placebo, and also reduced directly measured RLP-C levels to a greater extent in subgroups with higher versus lower baseline TG levels, in patients receiving statins versus no statins (MARINE), and in patients receiving medium/higher-intensity versus lower-intensity statins (ANCHOR). Strong correlations were found between calculated and directly measured RLP-C for baseline, end-of-treatment, and percent change values in ANCHOR and MARINE (0.73-0.92; p < 0.0001 for all). Icosapent ethyl 4 g/day significantly reduced calculated and directly measured RLP-C levels versus placebo in patients with elevated TG levels from the MARINE and ANCHOR studies. Copyright © 2016 The Authors

  6. Aerobic mineralization of vinyl chlorides by a bacterium of the order Actinomycetales

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Phelps, T.J.; Malachowsky, K.; Schram, R.M.

    1991-04-01

    A gram-positive branched bacterium isolated from a trichloroethylene-degrading consortium mineralized vinyl chloride in growing cultures and cell suspensions. Greater than 67% of the (1,2-{sup 14}C)vinyl chloride was mineralized to carbon dioxide, with approximately 10% of the radioactivity appearing in {sup 14}C-aqueous-phase products.

  7. 40 CFR 721.9965 - Fatty acids, C10-13 - branched, vinyl esters.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Fatty acids, C10-13 - branched, vinyl... Specific Chemical Substances § 721.9965 Fatty acids, C10-13 - branched, vinyl esters. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as fatty...

  8. 40 CFR 721.9965 - Fatty acids, C10-13 - branched, vinyl esters.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Fatty acids, C10-13 - branched, vinyl... Specific Chemical Substances § 721.9965 Fatty acids, C10-13 - branched, vinyl esters. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as fatty...

  9. Crown Ethers in Nonaqueous Electrolytes for Lithium/Air Batteries

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xu, Wu; Xiao, Jie; Wang, Deyu

    2010-02-04

    The effects of three crown ethers, 12-crown-4, 15-crown-5, and 18-crown-6, as additives and co-solvents in non-aqueous electrolytes on the cell performance of primary Li/air batteries operated in a dry air environment were investigated. Crown ethers have large effects on the discharge performance of non-aqueous electrolytes in Li/air batteries. A small amount (normally less than 10% by weight or volume in electrolytes) of 12-Crown-4 and 15-crown-5 reduces the battery performance and a minimum discharge capacity appears at the crown ether content of ca. 5% in the electrolytes. However, when the content increases to about 15%, both crown ethers improve the capacitymore » of Li/air cells by about 28% and 16%, respectively. 15-Crown-5 based electrolytes even show a maximum discharge capacity in the crown ether content range from 10% to 15%. On the other hand, the increase of 18-crown-6 amount in the electrolytes continuously lowers of the cell performance. The different battery performances of these three crown ethers in electrolytes are explained by the combined effects from the electrolytes’ contact angle, oxygen solubility, viscosity, ionic conductivity, and the stability of complexes formed between crown ether molecules and lithium ions.« less

  10. Field and laboratory evidence for intrinsic biodegradation of vinyl chloride contamination in a Fe(III)-reducing aquifer

    USGS Publications Warehouse

    Bradley, P.M.; Chapelle, F.H.; Wilson, J.T.

    1998-01-01

    Intrinsic bioremediation of chlorinated ethenes in anaerobic aquifers previously has not been considered feasible, due, in large part, to 1) the production of vinyl chloride during microbial reductive dechlorination of higher chlorinated contaminants and 2) the apparent poor biodegradability of vinyl chloride under anaerobic conditions. In this study, a combination of field geochemical analyses and laboratory radiotracer ([1,2-14C] vinyl chloride) experiments was utilized to assess the potential for intrinsic biodegradation of vinyl chloride contamination in an Fe(III)-reducing, anaerobic aquifer. Microcosm experiments conducted under Fe(III)-reducing conditions with material from the Fe(III)-reducing, chlorinated-ethene contaminated aquifer demonstrated significant oxidation of [1,2-14C] vinyl chloride to 14CO2 with no detectable production of ethene or other reductive dehalogenation products. Rates of degradation derived from the microcosm experiments (0.9-1.3% d-1) were consistent with field-estimated rates (0.03-0.2% d-1) of apparent vinyl chloride degradation. Field estimates of apparent vinyl chloride biodegradation were calculated using two distinct approaches; 1) a solute dispersion model and 2) a mass balance assessment. These findings demonstrate that degradation under Fe(III) reducing conditions can be an environmentally significant mechanism for intrinsic bioremediation of vinyl chloride in anaerobic ground-water systems.

  11. 29 CFR 1926.1117 - Vinyl chloride.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Vinyl chloride. 1926.1117 Section 1926.1117 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... chloride. Note: The requirements applicable to construction work under this section are identical to those...

  12. 19 CFR 10.99 - Importation of ethyl alcohol for nonbeverage purposes.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 false Importation of ethyl alcohol for nonbeverage... Provisions Ethyl Alcohol § 10.99 Importation of ethyl alcohol for nonbeverage purposes. (a) If claim is made... of ethyl alcohol of an alcoholic strength by volume of 80 percent volume or higher under subheading...

  13. Diastereoselective synthesis of ethyl ( Z)-3-(8-methylimidazo-[1,2- a]pyrid-2-yl)-2-phenylthioacrylate. X-ray crystal structure and conformational analysis

    NASA Astrophysics Data System (ADS)

    Gautier, A.; Roche, D.; Métin, J.; Carpy, A.; Madesclaire, M.

    1995-09-01

    The title compound 2, a gem vinyl sulfide ester, has been obtained diastereoselectively (de > 98%) by action of the ethyl thiophenoxyacetate carbanion on the imidazo[1,2- a]pyridinecarbaldehyde 1 in a basic medium, at low temperature. The X-ray crystal structure of 2 (C 19H 19N 2O 2S: Mr = 338.43, triclinic, P 1¯, a = 8.193(3) Å, b = 10.090(2) Å, c = 10.981(4) Å, α = 88.12(2)°, β = 78.66(4)°, γ = 78.53(2)°, V = 872.3(6) Å3, Z = 2, Dcalc = 1.29 g cm -3, λ( Mo Kα) = 0.71069 Å, μ = 0.189 mm -1, F(000) = 356, T = 293 K, R = 0.043 for 3610 observed reflections) has been determined and confirmed the Z configuration. The molecule is almost planar except for the phenyl ring situated in an approximate perpendicular plane. Despite the presence of the conjugate double bonds of the vinyl ester group (acrylate), coplanar with the imidazopyridine heterocycle, there is no evidence of π-electron delocalization over the whole structure. The crystal cohesion is ensured by a dense network of van der Waals contacts. A conformational analysis of the Z and E isomers by means of a Monte Carlo search and a stochastic dynamics simulation in CHCl 3 has shown that according to the method the Z isomer is more stable than the E isomer by about 7 to 10 kJ mol -1.

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

    DOEpatents

    Crivello, J.V.

    1996-01-23

    Propenyl ether monomers of formula A(OCH{double_bond}CHCH{sub 3}){sub n} (V) 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.

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

    DOEpatents

    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.

  16. Divinyl ether synthase gene and protein, and uses thereof

    DOEpatents

    Howe, Gregg A [East Lansing, MI; Itoh, Aya [Tsuruoka, JP

    2011-09-13

    The present invention relates to divinyl ether synthase genes, proteins, and methods of their use. The present invention encompasses both native and recombinant wild-type forms of the synthase, as well as mutants and variant forms, some of which possess altered characteristics relative to the wild-type synthase. The present invention also relates to methods of using divinyl ether synthase genes and proteins, including in their expression in transgenic organisms and in the production of divinyl ether fatty acids, and to methods of suing divinyl ether fatty acids, including in the protection of plants from pathogens.

  17. Divinyl ether synthase gene, and protein and uses thereof

    DOEpatents

    Howe, Gregg A.; Itoh, Aya

    2006-12-26

    The present invention relates to divinyl ether synthase genes, proteins, and methods of their use. The present invention encompasses both native and recombinant wild-type forms of the synthase, as well as mutants and variant forms, some of which possess altered characteristics relative to the wild-type synthase. The present invention also relates to methods of using divinyl ether synthase genes and proteins, including in their expression in transgenic organisms and in the production of divinyl ether fatty acids, and to methods of suing divinyl ether fatty acids, including in the protection of plants from pathogens.

  18. 40 CFR 180.483 - O-[2-(1,1-Dimethylethyl)-5-pyrimidinyl] O-ethyl-O-(1-methyl-ethyl) phosphorothioate; tolerances...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false O-[2-(1,1-Dimethylethyl)-5-pyrimidinyl] O-ethyl-O-(1-methyl-ethyl) phosphorothioate; tolerances for residues. 180.483 Section 180.483... EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Specific Tolerances § 180.483 O-[2-(1,1-Dimethylethyl)-5...

  19. Determining the partial photoionization cross-sections of ethyl radicals.

    PubMed

    FitzPatrick, B L; Maienschein-Cline, M; Butler, L J; Lee, S-H; Lin, J J

    2007-12-13

    Using a crossed laser-molecular beam scattering apparatus, these experiments photodissociate ethyl chloride at 193 nm and detect the Cl and ethyl products, resolved by their center-of-mass recoil velocities, with vacuum ultraviolet photoionization. The data determine the relative partial cross-sections for the photoionization of ethyl radicals to form C2H5+, C2H4+, and C2H3+ at 12.1 and 13.8 eV. The data also determine the internal energy distribution of the ethyl radical prior to photoionization, so we can assess the internal energy dependence of the photoionization cross-sections. The results show that the C2H4++H and C2H3++H2 dissociative photoionization cross-sections strongly depend on the photoionization energy. Calibrating the ethyl radical partial photoionization cross-sections relative to the bandwidth-averaged photoionization cross-section of Cl atoms near 13.8 eV allows us to use these data in conjunction with literature estimates of the Cl atom photoionization cross-sections to put the present bandwidth-averaged cross-sections on an absolute scale. The resulting bandwidth-averaged cross-section for the photoionization of ethyl radicals to C2H5+ near 13.8 eV is 8+/-2 Mb. Comparison of our 12.1 eV data with high-resolution ethyl radical photoionization spectra allows us to roughly put the high-resolution spectrum on the same absolute scale. Thus, one obtains the photoionization cross-section of ethyl radicals to C2H5+ from threshold to 12.1 eV. The data show that the onset of the C2H4++H dissociative photoionization channel is above 12.1 eV; this result offers a simple way to determine whether the signal observed in photoionization experiments on complex mixtures is due to ethyl radicals. We discuss an application of the results for resolving the product branching in the O+allyl bimolecular reaction.

  20. Supercritical antisolvent co-precipitation of rifampicin and ethyl cellulose.

    PubMed

    Djerafi, Rania; Swanepoel, Andri; Crampon, Christelle; Kalombo, Lonji; Labuschagne, Philip; Badens, Elisabeth; Masmoudi, Yasmine

    2017-05-01

    Rifampicin-loaded submicron-sized particles were prepared through supercritical anti-solvent process using ethyl cellulose as polymeric encapsulating excipient. Ethyl acetate and a mixture of ethyl acetate/dimethyl sulfoxide (70/30 and 85/15) were used as solvents for both drug and polymeric excipient. When ethyl acetate was used, rifampicin was crystallized separately without being embedded within the ethyl cellulose matrix while by using the ethyl acetate/dimethyl sulfoxide mixture, reduced crystallinity of the active ingredient was observed and a simultaneous precipitation of ethyl cellulose and drug was achieved. The effect of solvent/CO 2 molar ratio and polymer/drug mass ratio on the co-precipitates morphology and drug loading was investigated. Using the solvent mixture, co-precipitates with particle sizes ranging between 190 and 230nm were obtained with drug loading and drug precipitation yield from respectively 8.5 to 38.5 and 42.4 to 77.2% when decreasing the ethyl cellulose/rifampicin ratio. Results show that the solvent nature and the initial drug concentrations affect morphology and drug precipitation yield of the formulations. In vitro dissolution studies revealed that the release profile of rifampicin was sustained when co-precipitation was carried out with the solvent mixture. It was demonstrated that the drug to polymer ratio influenced amorphous content of the SAS co-precipitates. Differential scanning calorimetry thermograms and infrared spectra revealed that there is neither interaction between rifampicin and the polymer nor degradation of rifampicin during co-precipitation. In addition, stability stress tests on SAS co-precipitates were carried out at 75% relative humidity and room temperature in order to evaluate their physical stability. SAS co-precipitates were X-ray amorphous and remained stable after 6months of storage. The SAS co-precipitation process using a mixture of ethyl acetate/dimethyl sulfoxide demonstrates that this strategy can

  1. Controlled grafting of vinylic monomers on polyolefins: a robust mathematical modeling approach

    PubMed Central

    Saeb, Mohammad Reza; Rezaee, Babak; Shadman, Alireza; Formela, Krzysztof; Ahmadi, Zahed; Hemmati, Farkhondeh; Kermaniyan, Tayebeh Sadat; Mohammadi, Yousef

    2017-01-01

    Abstract Experimental and mathematical modeling analyses were used for controlling melt free-radical grafting of vinylic monomers on polyolefins and, thereby, reducing the disturbance of undesired cross-linking of polyolefins. Response surface, desirability function, and artificial intelligence methodologies were blended to modeling/optimization of grafting reaction in terms of vinylic monomer content, peroxide initiator concentration, and melt-processing time. An in-house code was developed based on artificial neural network that learns and mimics processing torque and grafting of glycidyl methacrylate (GMA) typical vinylic monomer on high-density polyethylene (HDPE). Application of response surface and desirability function enabled concurrent optimization of processing torque and GMA grafting on HDPE, through which we quantified for the first time competition between parallel reactions taking place during melt processing: (i) desirable grafting of GMA on HDPE; (ii) undesirable cross-linking of HDPE. The proposed robust mathematical modeling approach can precisely learn the behavior of grafting reaction of vinylic monomers on polyolefins and be placed into practice in finding exact operating condition needed for efficient grafting of reactive monomers on polyolefins. PMID:29491797

  2. Controlled grafting of vinylic monomers on polyolefins: a robust mathematical modeling approach.

    PubMed

    Saeb, Mohammad Reza; Rezaee, Babak; Shadman, Alireza; Formela, Krzysztof; Ahmadi, Zahed; Hemmati, Farkhondeh; Kermaniyan, Tayebeh Sadat; Mohammadi, Yousef

    2017-01-01

    Experimental and mathematical modeling analyses were used for controlling melt free-radical grafting of vinylic monomers on polyolefins and, thereby, reducing the disturbance of undesired cross-linking of polyolefins. Response surface, desirability function, and artificial intelligence methodologies were blended to modeling/optimization of grafting reaction in terms of vinylic monomer content, peroxide initiator concentration, and melt-processing time. An in-house code was developed based on artificial neural network that learns and mimics processing torque and grafting of glycidyl methacrylate (GMA) typical vinylic monomer on high-density polyethylene (HDPE). Application of response surface and desirability function enabled concurrent optimization of processing torque and GMA grafting on HDPE, through which we quantified for the first time competition between parallel reactions taking place during melt processing: (i) desirable grafting of GMA on HDPE; (ii) undesirable cross-linking of HDPE. The proposed robust mathematical modeling approach can precisely learn the behavior of grafting reaction of vinylic monomers on polyolefins and be placed into practice in finding exact operating condition needed for efficient grafting of reactive monomers on polyolefins.

  3. Telotristat Ethyl, a Tryptophan Hydroxylase Inhibitor for the Treatment of Carcinoid Syndrome.

    PubMed

    Kulke, Matthew H; Hörsch, Dieter; Caplin, Martyn E; Anthony, Lowell B; Bergsland, Emily; Öberg, Kjell; Welin, Staffan; Warner, Richard R P; Lombard-Bohas, Catherine; Kunz, Pamela L; Grande, Enrique; Valle, Juan W; Fleming, Douglas; Lapuerta, Pablo; Banks, Phillip; Jackson, Shanna; Zambrowicz, Brian; Sands, Arthur T; Pavel, Marianne

    2017-01-01

    Purpose Preliminary studies suggested that telotristat ethyl, a tryptophan hydroxylase inhibitor, reduces bowel movement (BM) frequency in patients with carcinoid syndrome. This placebo-controlled phase III study evaluated telotristat ethyl in this setting. Patients and Methods Patients (N = 135) experiencing four or more BMs per day despite stable-dose somatostatin analog therapy received (1:1:1) placebo, telotristat ethyl 250 mg, or telotristat ethyl 500 mg three times per day orally during a 12-week double-blind treatment period. The primary end point was change from baseline in BM frequency. In an open-label extension, 115 patients subsequently received telotristat ethyl 500 mg. Results Estimated differences in BM frequency per day versus placebo averaged over 12 weeks were -0.81 for telotristat ethyl 250 mg ( P < .001) and ‒0.69 for telotristat ethyl 500 mg ( P < .001). At week 12, mean BM frequency reductions per day for placebo, telotristat ethyl 250 mg, and telotristat ethyl 500 mg were -0.9, -1.7, and -2.1, respectively. Responses, predefined as a BM frequency reduction ≥ 30% from baseline for ≥ 50% of the double-blind treatment period, were observed in 20%, 44%, and 42% of patients given placebo, telotristat ethyl 250 mg, and telotristat ethyl 500 mg, respectively. Both telotristat ethyl dosages significantly reduced mean urinary 5-hydroxyindole acetic acid versus placebo at week 12 ( P < .001). Mild nausea and asymptomatic increases in gamma-glutamyl transferase were observed in some patients receiving telotristat ethyl. Follow-up of patients during the open-label extension revealed no new safety signals and suggested sustained BM responses to treatment. Conclusion Among patients with carcinoid syndrome not adequately controlled by somatostatin analogs, treatment with telotristat ethyl was generally safe and well tolerated and resulted in significant reductions in BM frequency and urinary 5-hydroxyindole acetic acid.

  4. Vinyl Sulfones as Antiparasitic Agents and a Structural Basis for Drug Design*

    PubMed Central

    Kerr, Iain D.; Lee, Ji H.; Farady, Christopher J.; Marion, Rachael; Rickert, Mathias; Sajid, Mohammed; Pandey, Kailash C.; Caffrey, Conor R.; Legac, Jennifer; Hansell, Elizabeth; McKerrow, James H.; Craik, Charles S.; Rosenthal, Philip J.; Brinen, Linda S.

    2009-01-01

    Cysteine proteases of the papain superfamily are implicated in a number of cellular processes and are important virulence factors in the pathogenesis of parasitic disease. These enzymes have therefore emerged as promising targets for antiparasitic drugs. We report the crystal structures of three major parasite cysteine proteases, cruzain, falcipain-3, and the first reported structure of rhodesain, in complex with a class of potent, small molecule, cysteine protease inhibitors, the vinyl sulfones. These data, in conjunction with comparative inhibition kinetics, provide insight into the molecular mechanisms that drive cysteine protease inhibition by vinyl sulfones, the binding specificity of these important proteases and the potential of vinyl sulfones as antiparasitic drugs. PMID:19620707

  5. Design, Sustainable Synthesis, and Programmed Reactions of Templated N-Heteroaryl-Fused Vinyl Sultams.

    PubMed

    Laha, Joydev K; Sharma, Shubhra; Kirar, Seema; Banerjee, Uttam C

    2017-09-15

    A de novo design and synthesis of N-heteroaryl-fused vinyl sultams as templates for programming chemical reactions on vinyl sultam periphery or (hetero)aryl ring is described. The key features include rational designing and sustainable synthesis of the template, customized reactions of vinyl sultams at C═C bond or involving N-S bond cleavage, and reactions on the periphery of the heteroaryl ring for late-stage diversification. The simple, easy access to the template coupled with opportunities for the synthesis of diversely functionalized heterocyles from a single template constitutes a rare study in contemporary organic synthesis.

  6. Environmentally Friendly Bio-Based Vinyl Ester Resins for Military Composite Structures

    DTIC Science & Technology

    2008-12-01

    composites, fatty acid , vinyl ester 9. Distribution $tatement (requr’iedl lsmanuscript subjectto export control? E ruo I yes Circfe appropriate l tter and...resins is to replace some or all of the styrene with fatty acid -based monomers. These fatty acid vinyl ester resins allow for the formulation of high...validation studies have been performed, showing that the fatty acid -based resins have sufficient, modulus, strength, glass transition temperature, and

  7. High Performance Fatty Acid-Based Vinyl Ester Resin for Liquid Molding

    DTIC Science & Technology

    2007-07-01

    High Performance Fatty Acid -Based Vinyl Ester Resin for Liquid Molding by Xing Geng, John J. La Scala, James M. Sands, and Giuseppe R...it to the originator. Army Research Laboratory Aberdeen Proving Ground, MD 21005-5069 ARL-RP-184 July 2007 High Performance Fatty Acid ...CONTRACT NUMBER 5b. GRANT NUMBER 4. TITLE AND SUBTITLE High Performance Fatty Acid -Based Vinyl Ester Resin for Liquid Molding 5c. PROGRAM

  8. Aerobic mineralization of vinyl chloride by a bacterium of the order Actinomycetales.

    PubMed Central

    Phelps, T J; Malachowsky, K; Schram, R M; White, D C

    1991-01-01

    A gram-positive branched bacterium isolated from a trichloroethylene-degrading consortium mineralized vinyl chloride in growing cultures and cell suspensions. Greater than 67% of the [1,2-14C]vinyl chloride was mineralized to carbon dioxide, with approximately 10% of the radioactivity appearing in cell biomass and another 10% appearing in 14C-aqueous-phase products. PMID:1905522

  9. Improved sample preparation for GC-MS-SIM analysis of ethyl carbamate in wine.

    PubMed

    Nóbrega, Ian C C; Pereira, Giuliano E; Silva, Marileide; Pereira, Elainy V S; Medeiros, Marcelo M; Telles, Danuza L; Albuquerque, Eden C; Oliveira, Juliane B; Lachenmeier, Dirk W

    2015-06-15

    An improved sample preparation procedure for analysis of carcinogenic ethyl carbamate (EC) in wine by GC-MS-SIM is proposed. Differences over AOAC reference procedure were: (1) use of EC-d5 as internal standard instead of less similar propyl carbamate; (2) extraction by diethyl ether instead of more toxic dichloromethane, and (3) concentration by vacuum automated parallel evaporation instead of more time and work consuming rotary evaporation. Mean recovery was 104.4%, intraday precision was 6.7% (3.4 μg L(-)(1)) and 1.7% (88.5 μg L(-)(1)), regression coefficient was 0.999 in the linear working range of 3-89 μg L(-)(1), and limits of detection and quantification were 0.4 and 1.2 μg L(-)(1). Applicability was demonstrated by analysis (in triplicate) of 5 wine samples. EC concentration ranged from 5.2 ± 0.2 to 29.4 ± 1.5 μg L(-)(1). The analytical method is selective, accurate, repeatable, linear, and has similar method performance as the reference method along with the several mentioned advantages. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Scientists Toast the Discovery of Vinyl Alcohol in Interstellar Space

    NASA Astrophysics Data System (ADS)

    2001-10-01

    Astronomers using the National Science Foundation's 12 Meter Telescope at Kitt Peak, AZ, have discovered the complex organic molecule vinyl alcohol in an interstellar cloud of dust and gas near the center of the Milky Way Galaxy. The discovery of this long-sought compound could reveal tantalizing clues to the mysterious origin of complex organic molecules in space. Vinyl Alcohol and its fellow isomers "The discovery of vinyl alcohol is significant," said Barry Turner, a scientist at the National Radio Astronomy Observatory (NRAO) in Charlottesville, Va., "because it gives us an important tool for understanding the formation of complex organic compounds in interstellar space. It may also help us better understand how life might arise elsewhere in the Cosmos." Vinyl alcohol is an important intermediary in many organic chemistry reactions on Earth, and the last of the three stable members of the C2H4O group of isomers (molecules with the same atoms, but in different arrangements) to be discovered in interstellar space. Turner and his colleague A. J. Apponi of the University of Arizona's Steward Observatory in Tucson detected the vinyl alcohol in Sagittarius B -- a massive molecular cloud located some 26,000 light-years from Earth near the center of our Galaxy. The astronomers were able to detect the specific radio signature of vinyl alcohol during the observational period of May and June of 2001. Their results have been accepted for publication in the Astrophysical Journal Letters. Of the approximately 125 molecules detected in interstellar space, scientists believe that most are formed by gas-phase chemistry, in which smaller molecules (and occasionally atoms) manage to "lock horns" when they collide in space. This process, though efficient at creating simple molecules, cannot explain how vinyl alcohol and other complex chemicals are formed in detectable amounts. For many years now, scientists have been searching for the right mechanism to explain how the building

  11. Adsorption of poly(vinyl formamide-co-vinyl amine) (PVFA-co-PVAm) polymers on zinc, zinc oxide, iron, and iron oxide surfaces.

    PubMed

    Seifert, Susan; Simon, Frank; Baumann, Giesela; Hietschold, Michael; Seifert, Andreas; Spange, Stefan

    2011-12-06

    The adsorption of poly(vinyl formamide) (PVFA) and the statistic copolymers poly(vinyl formamide-co-vinyl amine) (PVFA-co-PVAm) onto zinc and iron metal particles as well as their oxides was investigated. The adsorbates were characterized by means of XPS, DRIFT spectroscopy, wet chemical analysis, and solvatochromic probes. Dicyano-bis-(1,10-phenanthroline)-iron(II) (1), 3-(4-amino-3-methylphenyl)-7-phenyl-benzo-[1,2-b:4,5-b']difuran-2,6-dione (2), and 4-tert-butyl-2-(dicyano-methylene)-5-[4-(diethylamino)-benzylidene]-Δ(3)-thiazoline (3) as solvatochromic probes were coadsorbed onto zinc oxide to measure various effects of surface polarity. The experimental findings showed that the adsorption mechanism of PVFA and PVFA-co-PVAm strongly depends on the degree of hydrolysis of PVFA and pH values and also on the kind of metal or metal oxide surfaces that were employed as adsorbents. The adsorption mechanism of PVFA/PVFA-co-PVAm onto zinc oxide and iron oxide surfaces is mainly affected by electrostatic interactions. Particularly in the region of pH 5, the adsorption of PVFA/PVFA-co-PVAm onto zinc and iron metal particles is additionally influenced by redox processes, dissolution, and complexation reactions. © 2011 American Chemical Society

  12. A modification of the Hammett equation for predicting ionisation constants of p-vinyl phenols.

    PubMed

    Sipilä, Julius; Nurmi, Harri; Kaukonen, Ann Marie; Hirvonen, Jouni; Taskinen, Jyrki; Yli-Kauhaluoma, Jari

    2005-01-01

    Currently there are several compounds used as drugs or studied as new chemical entities, which have an electron withdrawing group connected to a vinylic double bond in a phenolic or catecholic core structure. These compounds share a common feature--current computational methods utilizing the Hammett type equation for the prediction of ionisation constants fail to give accurate prediction of pK(a)'s for compounds containing the vinylic moiety. The hypothesis was that the effect of electron-withdrawing substituents on the pK(a) of p-vinyl phenols is due to the delocalized electronic structure of these compounds. Thus, this effect should be additive for multiple substituents attached to the vinylic double bond and quantifiable by LFER-based methods. The aim of this study was to produce an improved equation with a reduced tendency to underestimate the effect of the double bond on the ionisation of the phenolic hydroxyl. To this end a set of 19 para-substituted vinyl phenols was used. The ionisation constants were measured potentiometrically, and a training set of 10 compounds was selected to build a regression model (r2 = 0.987 and S.E. = 0.09). The average error with an external test set of six compounds was 0.19 for our model and 1.27 for the ACD-labs 7.0. Thus, we have been able to significantly improve the existing model for prediction of the ionisation constants of substituted p-vinyl phenols.

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

    EPA Science Inventory

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

  14. Icosapent ethyl: a review of its use in severe hypertriglyceridemia.

    PubMed

    Kim, Esther S; McCormack, Paul L

    2014-12-01

    Icosapent ethyl (Vascepa®) is a high-purity ethyl ester of eicosapentaenoic acid (EPA) that is de-esterified to EPA following oral administration. Both EPA and docosahexaenoic acid (DHA) are long-chain omega-3 fatty acids that have been associated with triglyceride (TG)-lowering. However, DHA has been associated with increased low-density lipoprotein cholesterol (LDL-C) levels. Icosapent ethyl contains ≥96 % of the EPA ethyl ester, does not contain DHA, and is approved in the USA for use as an adjunct to diet to lower TG levels in adult patients with severe (≥500 mg/dL [≥5.65 mmol/L]) hypertriglyceridemia. In a pivotal phase III trial, oral icosapent ethyl 4 g/day significantly decreased the placebo-corrected median TG levels by 33.1 %. It did not increase LDL-C, had favorable effects on other lipid parameters, and had a tolerability profile similar to that of placebo. Therefore, icosapent ethyl is an effective and well-tolerated agent for the treatment of severe hypertriglyceridemia in adults.

  15. p-Bromodiphenyl ether

    Integrated Risk Information System (IRIS)

    p - Bromodiphenyl ether ; CASRN 101 - 55 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcin

  16. 27 CFR 21.32 - Formula No. 1.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... methyl isobutyl ketone; 1 gallon of mixed isomers of nitropropane; or 1 gallon of methyl n- butyl ketone.... 551.Acetaldehyde. 552.Other aldehydes. 561.Ethyl ether. 562.Other ethers. 571.Ethylene dibromide. 572...

  17. 27 CFR 21.32 - Formula No. 1.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... methyl isobutyl ketone; 1 gallon of mixed isomers of nitropropane; or 1 gallon of methyl n- butyl ketone.... 551.Acetaldehyde. 552.Other aldehydes. 561.Ethyl ether. 562.Other ethers. 571.Ethylene dibromide. 572...

  18. 27 CFR 21.32 - Formula No. 1.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... methyl isobutyl ketone; 1 gallon of mixed isomers of nitropropane; or 1 gallon of methyl n- butyl ketone.... 551.Acetaldehyde. 552.Other aldehydes. 561.Ethyl ether. 562.Other ethers. 571.Ethylene dibromide. 572...

  19. 27 CFR 21.32 - Formula No. 1.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... methyl isobutyl ketone; 1 gallon of mixed isomers of nitropropane; or 1 gallon of methyl n- butyl ketone.... 551.Acetaldehyde. 552.Other aldehydes. 561.Ethyl ether. 562.Other ethers. 571.Ethylene dibromide. 572...

  20. 27 CFR 21.32 - Formula No. 1.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... methyl isobutyl ketone; 1 gallon of mixed isomers of nitropropane; or 1 gallon of methyl n- butyl ketone.... 551.Acetaldehyde. 552.Other aldehydes. 561.Ethyl ether. 562.Other ethers. 571.Ethylene dibromide. 572...

  1. Dielectric Relaxation of the Ionic Liquid 1-Ethyl-3-methylimidazolium Ethyl Sulfate: Microwave and Far-IR Properties.

    PubMed

    Dhumal, Nilesh R; Kiefer, Johannes; Turton, David; Wynne, Klaas; Kim, Hyung J

    2017-05-11

    Dielectric relaxation of the ionic liquid, 1-ethyl-3-methylimidazolium ethyl sulfate (EMI + ETS - ), is studied using molecular dynamics (MD) simulations. The collective dynamics of polarization arising from cations and anions are examined. Characteristics of the rovibrational and translational components of polarization dynamics are analyzed to understand their respective roles in the microwave and terahertz regions of dielectric relaxation. The MD results are compared with the experimental low-frequency spectrum of EMI + ETS - , obtained via ultrafast optical Kerr effect (OKE) measurements.

  2. 40 CFR 180.430 - Fenoxaprop-ethyl; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... residues of the herbicide fenoxaprop-ethyl, including its metabolites and degradates, in or on the... for residues of the herbicide fenoxaprop-ethyl, including its metabolites and degradates, in or on the...

  3. 40 CFR 180.430 - Fenoxaprop-ethyl; tolerances for residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... residues of the herbicide fenoxaprop-ethyl, including its metabolites and degradates, in or on the... for residues of the herbicide fenoxaprop-ethyl, including its metabolites and degradates, in or on the...

  4. IRIS Toxicological Review of Decabromodiphenyl Ether (Final Report)

    EPA Science Inventory

    EPA announced the release of the final report, Toxicological Review of Decabromodiphenyl Ether: in support of the Integrated Risk Information System (IRIS). The updated Summary for Decabromodiphenyl Ether and accompanying toxicological review have been added to the IRIS Da...

  5. Tough poly(arylene ether) thermoplastics as modifiers for bismaleimides

    NASA Technical Reports Server (NTRS)

    Stenzenberger, H. D.; Roemer, W.; Hergenrother, P. M.; Jensen, B. J.

    1989-01-01

    Several aspects of research on thermoplastics as toughness modifiers are discussed, including the contribution of the backbone chemistry and the concentration of the poly(arylene ether) thermoplastic to fracture toughness, influence of the molecular weight of the poly(arylene ether) thermoplastic on neat resin fracture toughness, and the morphology of the thermoplastic modified networks. The results show that fracture toughness of brittle bismaleimide resins can be improved significantly with poly(arylene ether) thermoplastic levels of 20 percent by weight, and that high molecular weight poly(arylene ether) based on bisphenol A provides the highest degree of toughening. Preliminary composite evaluation shows that improvements in neat resin toughness translate into carbon fabric composite.

  6. Direct synthesis of ethanol from dimethyl ether and syngas over combined H-Mordenite and Cu/ZnO catalysts.

    PubMed

    Li, Xingang; San, Xiaoguang; Zhang, Yi; Ichii, Takashi; Meng, Ming; Tan, Yisheng; Tsubaki, Noritatsu

    2010-10-25

    Ethanol was directly synthesized from dimethyl ether (DME) and syngas with the combined H-Mordenite and Cu/ZnO catalysts that were separately loaded in a dual-catalyst bed reactor. Methyl acetate (MA) was formed by DME carbonylation over the H-Mordenite catalyst. Thereafter, ethanol and methanol were produced by MA hydrogenation over the Cu/ZnO catalyst. With the reactant gas containing 1.0% DME, the optimized temperature for the reaction was at 493 K to reach 100% conversion. In the products, the yield of methanol and ethanol could reach 46.3% and 42.2%, respectively, with a small amount of MA, ethyl acetate, and CO(2). This process is environmentally friendly as the main byproduct methanol can be recycled to DME by a dehydration reaction. In contrast, for the physically mixed catalysts, the low conversion of DME and high selectivity of methanol were observed.

  7. Wide-pore silica-based ether-bonded phases for separation of proteins by high-performance hydrophobic-interaction and size-exclusion chromatography.

    PubMed

    Miller, N T; Feibush, B; Karger, B L

    1984-12-21

    This paper examines the use of wide-pore silica-based hydrophilic ether-bonded phases for the chromatographic separation of proteins under mild elution conditions. In particular, ether phases of the following structure identical to Si-(CH2)3-O-(CH2-CH2-O)n-R, where n = 1, 2, 3 and R = methyl, ethyl or n-butyl, have been prepared. These phases can be employed either in high-performance hydrophobic-interaction or size-exclusion chromatography, depending on mobile phase conditions. In the hydrophobic-interaction mode, a gradient of decreasing salt concentration, e.g., from 3 M ammonium sulfate (pH 6.0, 25 degrees C), yields sharp peaks with high mass recovery of active proteins. In this mode, retention can be controlled by salt type and concentration, as well as by column temperature. In the size-exclusion mode, use of medium ionic strength, e.g., 0.5 M ammonium acetate (pH 6.0) yields linear calibration of log (MW[eta]) vs. retention volume. Even at 0.05 M salt concentration, no stationary phase charge effects on protein elution are observed. These bonded-phase columns exhibit good column-to-column reproducibility and constant retention for at least five months of continual use. Examples of the high-performance separation of proteins in both modes are illustrated.

  8. Indirect latex glove contamination and its inhibitory effect on vinyl polysiloxane polymerization.

    PubMed

    Kimoto, Katsuhiko; Tanaka, Kinya; Toyoda, Minoru; Ochiai, Kent T

    2005-05-01

    The inhibitory effect of indirect latex contamination on the polymerization of vinyl polysiloxane (VPS) impression material has been previously reported. However, the transfer of specific elements that cause inhibition has not been confirmed, nor has the removal of such contaminants been reported. This study examined the surfaces of materials commonly used in restorative procedures that were contaminated by indirect latex glove contact and then evaluated for inhibition of polymerization of VPS. The effect of selected cleansing procedures was then studied. Four experimental groups (n = 8) were prepared: (1) clean vinyl gloves (control), (2) clean gingival retraction cords (control), (3) contaminated vinyl gloves, and (4) contaminated gingival retraction cord. Microscopic evaluation of the appearance and the characterization of surface particulate contamination were performed for each. Three cleansing protocols were then evaluated for efficacy in cleaning vinyl glove surfaces contaminated by latex contact (n = 10): (1) brushing with water, (2) brushing with soap/rinsing with water, (3) cleansing with rubbing alcohol. The subsequent degree of VPS polymerization inhibition was evaluated subjectively. A chi-square test was used for data analysis (alpha=.05). Particulate sulfur elements and sulfur-chloride compounds were present on the contaminated substrates. None of the 3 cleansing procedures eliminated polymerization inhibition (P =.33). Residual elemental sulfur remained on all tested surfaces. Particulate sulfur and sulfur-chloride compounds were identified as the particulate contamination that resulted in polymerization inhibition of the tested VPS dental impression material. Removal of these contaminants from the tested vinyl gloves and gingival retraction cord was not possible with the 3 cleansing protocols tested in this study.

  9. Preparation of highly fluorinated diols containing ether linkages.

    NASA Technical Reports Server (NTRS)

    Rochow, S. E.; Stump, E. C., Jr.

    1970-01-01

    Hydroxy-terminated perfluoroethers and polyurethane resins derived from ethers have outstanding chemical resistance and good thermal properties. They can be used as potting compounds, coatings, and seals. The hydroxy-terminated ethers serve as intermediates in the synthesis of highly fluorinated elastomers and adhesives.

  10. Material with high dielectric constant, low dielectric loss, and good mechanical and thermal properties produced using multi-wall carbon nanotubes wrapped with poly(ether sulphone) in a poly(ether ether ketone) matrix

    NASA Astrophysics Data System (ADS)

    Zhang, Shuling; Wang, Hongsong; Wang, Guibin; Jiang, Zhenhua

    2012-07-01

    A material with high dielectric constant, low dielectric loss, and good mechanical and thermal properties was produced using multi-wall carbon nanotubes (MWCNTs) wrapped with poly(ether sulphone) (PES) dispersed in a poly(ether ether ketone) (PEEK) matrix. The material was fabricated using melt-blending, and MWCNT/PEEK composites show different degrees of improvement in the measured dielectric, mechanical, and thermal properties as compared to pure PEEK. This is attributed to the high conductivity of MWCNTs, the effect of wrapping MWCNTs with PES, the good dispersion of the wrapped MWCNTs in PEEK, and the strong interfacial adhesion between the wrapped MWCNTs and the PEEK.

  11. Improved adhesion performances of aramid fibers with vinyl epoxy via supercritical carbon dioxide modification

    NASA Astrophysics Data System (ADS)

    Qin, M. L.; Kong, H. J.; Yu, M. H.; Teng, C. Q.

    2017-06-01

    In this paper, aramid fibers were treated under supercritical carbon dioxide (SCCO2) with isocyanate terminated liquid nitrile rubber to improve the adhesion performances of vinyl epoxy composites. The interfacial shear strength (IFSS) of vinyl epoxy composites was investigated by micro-bond test. The results indicate that the surface modification of aramid fibers in SCCO2 was an efficient method to increase the adhesion performances between fibers and vinyl epoxy. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) were adopted to investigate the surface structure and composition of aramid fibers. The flexural strength and interlaminar shear strength (ILSS) of treated aramid fibers/vinyl epoxy composites was improved by 18.1% and 28.9% compared with untreated aramid fibers, respectively. Furthermore, the fractured surfaces of the composites were observed by SEM, which showed that the interfacial adhesion of composites has been remarkably changed.

  12. Successful Initial Development of Styrene Substitutes and Suppressants for Vinyl Ester Resin Formulations

    DTIC Science & Technology

    2003-08-01

    into a separatory funnel. Distilled water was added to remove the acid from the ether phase. The layers were allowed to separate, and the water layer...The reaction mixtures were removed from the heat 2 hr after the last acrylic acid aliquot was added. The acrylated oils were purified via ether... remove inhibitor and any unreacted acid , the reaction mixture was ether extracted (25). The mixture was dissolved in diethyl ether and poured into a

  13. Burnout of the organic vehicle in an electrically conductive thick-film paste

    NASA Astrophysics Data System (ADS)

    Liu, Zongrong; Chung, D. D. L.

    2004-11-01

    The burnout of the organic vehicle in a silver-particle, glass-free, electrically conductive, thick-film paste during firing in air was studied. For a vehicle consisting of ethyl cellulose dissolved in ether, burnout primarily involves the thermal decomposition of ethyl cellulose. The presence of ether with dissolved ethyl cellulose facilitates the burnout of ethyl cellulose. Excessive ethyl cellulose hinders the burnout. A high heating rate results in more residue after burnout. By interrupting the heating at 160°C for 15 min, the residue after subsequent burnout is diminished probably because of reduced temporal overlap of the processes of organic burnout and silver particle necking. By interrupting the heating at either 300°C or 385°C for 30 min, the temperature required for complete burnout is reduced. The addition of silver particles facilitates drying at room temperature and burnout upon heating.

  14. Preparation of vinyl acetate grafted natural rubber by irradiation method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Porntrairat, A.; Pattamaprom, C.

    Improvement in properties of natural rubber could be done by several methods. In this research, gamma radiation technique, which is simple, accurate, easy to control and clean, was applied to enhance the properties of natural rubber (NR) in latex state. The purpose of this research is to study the appropriate condition for preparing grafted natural rubber latex by using irradiation method. Vinyl acetate monomers (VAc) were grafted onto natural rubber latex (NR-g-PVAc) at 0-10 kGys by gamma radiation from Cobalt-60 source at room temperature. Physical properties of grafted natural rubber such as chloroform number, swelling ratio and gel content weremore » measured. The VAc content of NR-g-PVAc was investigated by titration and visualized by FTIR spectroscopy. The FTIR spectra of NR-g-PVAc prepared at 0-10 kGys showed characteristic peaks of the vinyl acetate confirming that VAc could be grafted onto natural rubber molecular chains effectively under appropriate irradiation conditions. From the result, radiation grafting was found to be a useful technique for grafting of vinyl acetate onto natural rubber.« less

  15. 76 FR 76766 - Standard on Vinyl Chloride; Extension of the Office of Management and Budget's (OMB) Approval of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-08

    ...] Standard on Vinyl Chloride; Extension of the Office of Management and Budget's (OMB) Approval of... requirements specified in the Standard on Vinyl Chloride (29 CFR 1910.1017). DATES: Comments must be submitted... of the collection of information requirements contained in the Vinyl Chloride (VC) Standard. (A...

  16. A new route to synthesize aryl acetates from carbonylation of aryl methyl ethers

    PubMed Central

    Yang, Youdi; Li, Shaopeng; Han, Buxing

    2018-01-01

    Ether bond activation is very interesting because the synthesis of many valuable compounds involves conversion of ethers. Moreover, C–O bond cleavage is also very important for the transformation of biomass, especially lignin, which abundantly contains ether bonds. Developing efficient methods to activate aromatic ether bonds has attracted much attention. However, this is a challenge because of the inertness of aryl ether bonds. We proposed a new route to activate aryl methyl ether bonds and synthesize aryl acetates by carbonylation of aryl methyl ethers. The reaction could proceed over RhCl3 in the presence of LiI and LiBF4, and moderate to high yields of aryl acetates could be obtained from transformation of various aryl methyl ethers with different substituents. It was found that LiBF4 could assist LiI to cleave aryl methyl ether bonds effectively. The reaction mechanism was proposed by a combination of experimental and theoretical studies. PMID:29795781

  17. S-Ethyl dipropylthiocarbamate (EPTC)

    Integrated Risk Information System (IRIS)

    Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) S - Ethyl dipropylth

  18. 75 FR 58315 - Hazardous Waste Management System; Identification and Listing of Hazardous Waste; Direct Final...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-24

    ... benzene, ethyl ether, methyl isobutyl ketone, n-butyl alcohol, cyclohexane, methanol. F005 Toluene, methyl... alcohol. U147 Maleic anhydride. U154 Methanol. U159 Methyl ethyl ketone. U161 Methyl isobutyl ketone. U213..., methyl isobutyl ketone, n-butyl alcohol, cyclohexane, methanol. F005 Toluene, methyl ethyl ketone, carbon...

  19. Anti-oxidant properties and polyphenolic profile screening of Vitis vinifera stems and leaves crude extracts grown in Perlis, Malaysia

    NASA Astrophysics Data System (ADS)

    Zakaria, Nursyahda; Zulkifli, Razauden Mohamed; Akhir, Fazrena Nadia Md; Basar, Norazah

    2014-03-01

    Grape has become a fast growing agricultural sector in Malaysia producing between 0.62 kg to 2.03 kg waste per vinestock. This study aims to generate useful information on anti-oxidative properties as well as polyphenolic composition of grapevine waste. Stems and leaves of Vitis vinifera cultivated in Perlis, Malaysia were extracted using methanol, ethyl acetate and petroleum ether. Ethyl acetate stems extract exhibited highest total phenolic content. While in DPPH assay, methanolic stems extract show the highest antioxidant activities. This result indicates that total phenolic content in the extracts may not contribute directly to the antioxidant activities. Thin Layer Chromatograms of all crude extracts exhibited good separation under solvent system petroleum ether-ethyl acetate (2:3) resulted in detection of resveratrol in ethyl acetate stems crude extract.

  20. Synthesis of aryl azides and vinyl azides via proline-promoted CuI-catalyzed coupling reactions.

    PubMed

    Zhu, Wei; Ma, Dawei

    2004-04-07

    The coupling reaction of aryl halides or vinyl iodide with sodium azide under catalysis of CuI/L-proline works at relatively low temperature to provide aryl azides or vinyl azides in good to excellent yields.

  1. 21 CFR 177.1980 - Vinyl chloride-propylene copolymers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... grams of granular sodium peroxide, 0.1 gram of powdered starch, and 0.02 gram potassium nitrate; and the... provisions of this section are not applicable to vinyl chloride-propylene copolymers used in food-packaging...

  2. Fragmentation dynamics of the ethyl bromide and ethyl iodide cations: a velocity-map imaging study.

    PubMed

    Gardiner, Sara H; Karsili, Tolga N V; Lipciuc, M Laura; Wilman, Edward; Ashfold, Michael N R; Vallance, Claire

    2014-02-07

    The photodissociation dynamics of ethyl bromide and ethyl iodide cations (C2H5Br(+) and C2H5I(+)) have been studied. Ethyl halide cations were formed through vacuum ultraviolet (VUV) photoionization of the respective neutral parent molecules at 118.2 nm, and were photolysed at a number of ultraviolet (UV) photolysis wavelengths, including 355 nm and wavelengths in the range from 236 to 266 nm. Time-of-flight mass spectra and velocity-map images have been acquired for all fragment ions and for ground (Br) and spin-orbit excited (Br*) bromine atom products, allowing multiple fragmentation pathways to be investigated. The experimental studies are complemented by spin-orbit resolved ab initio calculations of cuts through the potential energy surfaces (along the RC-Br/I stretch coordinate) for the ground and first few excited states of the respective cations. Analysis of the velocity-map images indicates that photoexcited C2H5Br(+) cations undergo prompt C-Br bond fission to form predominantly C2H5(+) + Br* products with a near-limiting 'parallel' recoil velocity distribution. The observed C2H3(+) + H2 + Br product channel is thought to arise via unimolecular decay of highly internally excited C2H5(+) products formed following radiationless transfer from the initial excited state populated by photon absorption. Broadly similar behaviour is observed in the case of C2H5I(+), along with an additional energetically accessible C-I bond fission channel to form C2H5 + I(+) products. HX (X = Br, I) elimination from the highly internally excited C2H5X(+) cation is deemed the most probable route to forming the C2H4(+) fragment ions observed from both cations. Finally, both ethyl halide cations also show evidence of a minor C-C bond fission process to form CH2X(+) + CH3 products.

  3. Process for the preparation of vinyl acetate

    DOEpatents

    Tustin, G.C.; Zoeller, J.R.; Depew, L.S.

    1998-02-17

    This invention pertains to the preparation of vinyl acetate by contacting within a contact zone a mixture of ketene and acetaldehyde with an acid catalyst at about one bar pressure and between about 85 and 200 C and removing the reaction products from the contact zone.

  4. Effect of different fractions from hydroalcoholic extract of Black Maca (Lepidium meyenii) on testicular function in adult male rats.

    PubMed

    Yucra, Sandra; Gasco, Manuel; Rubio, Julio; Nieto, Jessica; Gonzales, Gustavo F

    2008-05-01

    To evaluate the effect of different fractions of Black Maca (Lepidium meyenii), obtained from the hydroalcoholic extract, on spermatogenesis. Animal study. Animal and laboratory facilities at a university. Forty two adult male rats from the Holtzman strain (3 months old). Hydroalcoholic extract of Black Maca was partitioned with the following solvents: petroleum ether, chloroform, ethyl acetate, n-butanol, and water to obtain each fraction. Forty-two rats were divided in different groups according the fraction administered and vehicle. The hydroalcoholic extract of Black Maca and its fractions and vehicle were given orally by gavage for 7 days. Daily sperm production, epididymal sperm count, and sperm count in the vas deferens. Daily sperm production was higher in the ethyl acetate group compared with all other groups. The epididymal sperm count was higher in rats treated with ethyl acetate fraction compared with rats treated with vehicle (control), petroleum ether, n-butanol, or water fractions. The sperm count in vas deferens was lower in rats treated with ethyl acetate, petroleum ether, or water fractions compared with the control group; thus, the sperm count in vas deferens in rats treated with chloroform and n-butanol fractions was higher than in the petroleum ether group. The greatest effect on spermatogenesis was observed in the ethyl acetate fraction from the hydroalcoholic extract of Black Maca, suggesting that the compounds related to the beneficial effect on sperm production of Black Maca are presented in this fraction. Antioxidant components could play a role in the effect of increased epididymal sperm concentration observed in the model.

  5. 40 CFR 180.595 - Flufenpyr-ethyl; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... residues of the herbicide, flufenpyr-ethyl; acetic acid, [2-chloro-4-fluoro-5-[5-methyl-6-oxo-4... established for residues of the herbicide flufenpyr-ethyl; acetic acid, [2-chloro-4-fluoro-5-[5-methyl-6-oxo-4...

  6. 40 CFR 180.595 - Flufenpyr-ethyl; tolerances for residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... residues of the herbicide, flufenpyr-ethyl; acetic acid, [2-chloro-4-fluoro-5-[5-methyl-6-oxo-4... established for residues of the herbicide flufenpyr-ethyl; acetic acid, [2-chloro-4-fluoro-5-[5-methyl-6-oxo-4...

  7. 40 CFR 180.595 - Flufenpyr-ethyl; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... residues of the herbicide, flufenpyr-ethyl; acetic acid, [2-chloro-4-fluoro-5-[5-methyl-6-oxo-4... established for residues of the herbicide flufenpyr-ethyl; acetic acid, [2-chloro-4-fluoro-5-[5-methyl-6-oxo-4...

  8. 40 CFR 180.595 - Flufenpyr-ethyl; tolerances for residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... residues of the herbicide, flufenpyr-ethyl; acetic acid, [2-chloro-4-fluoro-5-[5-methyl-6-oxo-4... established for residues of the herbicide flufenpyr-ethyl; acetic acid, [2-chloro-4-fluoro-5-[5-methyl-6-oxo-4...

  9. 40 CFR 180.595 - Flufenpyr-ethyl; tolerances for residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... residues of the herbicide, flufenpyr-ethyl; acetic acid, [2-chloro-4-fluoro-5-[5-methyl-6-oxo-4... established for residues of the herbicide flufenpyr-ethyl; acetic acid, [2-chloro-4-fluoro-5-[5-methyl-6-oxo-4...

  10. Two-year drinking water carcinogenicity study of methyl tertiary-butyl ether (MTBE) in Wistar rats.

    PubMed

    Dodd, Darol; Willson, Gabrielle; Parkinson, Horace; Bermudez, Edilberto

    2013-07-01

    Methyl tertiary-butyl ether (MTBE) has been used as a gasoline additive to reduce tailpipe emissions and its use has been discontinued. There remains a concern that drinking water sources have been contaminated with MTBE. A two-year drinking water carcinogenicity study of MTBE was conducted in Wistar rats (males, 0, 0.5, 3, 7.5 mg ml(-1); and females, 0, 0.5, 3, and 15 mg ml(-1)). Body weights were unaffected and water consumption was reduced in MTBE-exposed males and females. Wet weights of male kidneys were increased at the end of two years of exposure to 7.5 mg ml(-1) MTBE. Chronic progressive nephropathy was observed in males and females, was more severe in males, and was exacerbated in the high MTBE exposure groups. Brain was the only tissue with a statistically significant finding of neoplasms. One astrocytoma (1/50) was found in a female rat (15 mg ml(-1)). The incidence of brain astrocytomas in male rats was 1/50, 1/50, 1/50 and 4/50 for the 0, 0.5, 3 and 7.5 mg ml(-1) exposure groups, respectively. This was a marginally significant statistical trend, but not statistically significant when pairwise comparisons were made or when multiple comparisons were taken into account. The incidence of astrocytoma fell within historical control ranges for Wistar rats, and the brain has not been identified as a target organ following chronic administration of MTBE, ethyl tert-butyl ether, or tertiary butyl alcohol (in drinking water) to mice and rats. We conclude that the astrocytomas observed in this study are not associated with exposure to MTBE. Copyright © 2011 John Wiley & Sons, Ltd.

  11. Crystalline imide/arylene ether copolymers

    NASA Technical Reports Server (NTRS)

    Jensen, Brian J. (Inventor); Hergenrother, Paul M. (Inventor); Bass, Robert G. (Inventor)

    1995-01-01

    Crystalline imide/arylene ether block copolymers are prepared by reacting anhydride terminated poly(amic acids) with amine terminated poly)arylene ethers) in polar aprotic solvents and chemically or thermally cyclodehydrating the resulting intermediate poly(amic acids). The block copolymers of the invention have one glass transition temperature or two, depending on the particular structure and/or the compatibility of the block units. Most of these crystalline block copolymers for tough, solvent resistant films with high tensile properties. While all of the copolymers produced by the present invention are crystalline, testing reveals that copolymers with longer imide blocks or higher imide content have increased crystallinity.

  12. Spectroscopy reveals that ethyl esters interact with proteins in wine.

    PubMed

    Di Gaspero, Mattia; Ruzza, Paolo; Hussain, Rohanah; Vincenzi, Simone; Biondi, Barbara; Gazzola, Diana; Siligardi, Giuliano; Curioni, Andrea

    2017-02-15

    Impairment of wine aroma after vinification is frequently associated to bentonite treatments and this can be the result of protein removal, as recently demonstrated for ethyl esters. To evaluate the existence of an interaction between wine proteins and ethyl esters, the effects induced by these fermentative aroma compounds on the secondary structure and stability of VVTL1, a Thaumatin-like protein purified from wine, was analyzed by Synchrotron Radiation Circular Dichroism (SRCD) spectroscopy. The secondary structure of wine VVTL1 was not strongly affected by the presence of selected ethyl esters. In contrast, VVTL1 stability was slightly increased by the addition of ethyl-octanoate, -decanoate and -dodecanoate, but decreased by ethyl-hexanoate. This indicates the existence of an interaction between VVTL1 and at least some aroma compounds produced during fermentation. The data suggest that proteins removal from wine by bentonite can result in indirect removal of at least some aroma compounds associated with them. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. The Ether Wind and the Global Positioning System.

    ERIC Educational Resources Information Center

    Muller, Rainer

    2000-01-01

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

  14. Imide/arylene ether copolymers with pendent trifluoromethyl groups

    NASA Technical Reports Server (NTRS)

    Jensen, Brian J.; Havens, Stephen J.

    1992-01-01

    A series of imide/arylene ether block copolymers were prepared using an arylene ether block containing a hexafluoroisopropylidene group and an imide block containing a hexafluoroisopropylidene and a trifluoromethyl group in the polymer backbone. The copolymers were characterized and mechanical properties were determined and compared to the homopolymers.

  15. Process for the preparation of vinyl acetate

    DOEpatents

    Tustin, Gerald Charles; Zoeller, Joseph Robert; Depew, Leslie Sharon

    1998-01-01

    This invention pertains to the preparation of vinyl acetate by contacting within a contact zone a mixture of ketene and acetaldehyde with an acid catalyst at about one bar pressure and between about 85.degree. and 200.degree. C. and removing the reaction products from the contact zone.

  16. Vinylation of nitro-substituted indoles, quinolinones, and anilides with grignard reagents.

    PubMed

    Egris, Riccardo; Villacampa, Mercedes; Menéndez, J Carlos

    2009-10-19

    The reaction of vinyl Grignard reagents with o-methoxynitroarenes containing an electron-releasing substituent para to the nitro group proceeds through a pathway that is different from the initially expected Bartoli indole synthesis. Thus, instead of giving fused indole derivatives, these reactions provide a very mild and efficient new procedure for the synthesis of synthetically relevant aromatic systems containing an o-nitrovinyl moiety, such as 5-nitro-4-vinylindoles, 6-nitro-7-vinylindoles, 6-nitro-5-vinyl-2(1H)quinolinones, and 4-nitro-3-vinylanilines.

  17. Safety Assessment of Alkyl PEG/PPG Ethers as Used in Cosmetics.

    PubMed

    Fiume, Monice M; Heldreth, Bart; Bergfeld, Wilma F; Belsito, Donald V; Hill, Ronald A; Klaassen, Curtis D; Liebler, Daniel C; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Andersen, F Alan

    2016-07-01

    The Cosmetic Ingredient Review (CIR) Expert Panel assessed the safety of 131 alkyl polyethylene glycol (PEG)/polypropylene glycol ethers as used in cosmetics, concluding that these ingredients are safe in the present practices of use and concentration described in this safety assessment when formulated to be nonirritating. Most of the alkyl PEG/PPG ethers included in this review are reported to function in cosmetics as surfactants, skin-conditioning agents, and/or emulsifying agents. The alkyl PEG/PPG ethers share very similar physiochemical properties as the alkyl PEG ethers, which were reviewed previously by the CIR Expert Panel and found safe when formulated to be nonirritating. The alkyl PEG ethers differ by the inclusion of PPG repeat units, which are used to fine-tune the surfactant properties of this group. The Panel relied heavily on data on analogous ingredients, extracted from the alkyl PEG ethers and PPG reports, when making its determination of safety. © The Author(s) 2016.

  18. Methyl ethyl ketone (MEK)

    Integrated Risk Information System (IRIS)

    Methyl ethyl ketone ( MEK ) ( CASRN 78 - 93 - 3 ) Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Nonc

  19. Regulating Drug Release Behavior and Kinetics from Matrix Tablets Based on Fine Particle-Sized Ethyl Cellulose Ether Derivatives: An In Vitro and In Vivo Evaluation

    PubMed Central

    Shah, Kifayat Ullah; Khan, Gul Majid

    2012-01-01

    The design and fabrication of sustained/controlled release dosage forms, employing new excipients capable of extending/controlling the release of drugs from the dosage forms over prolonged periods, has worked well in achieving optimally enhanced therapeutic levels of the drugs. In this sense, the objective of this study was to investigate the suitability of selected cellulose ether derivatives for use in direct compression (DC) and as efficient drug release controlling agents. Controlled release matrix tablets of ciprofloxacin were prepared at different drug-to-polymer (D : P) ratios by direct compression using a fine particle sized ethylcellulose ether derivative (ETHOCEL Standard Premium 7FP) as rate controlling polymer. The tablets obtained were evaluated for various physico-chemical characteristics and in-vitro drug release studies were conducted in phosphate buffer (pH 7.4) using PharmaTest dissolution apparatus at constant temperature of 37°C ± 0.1. Similarity factor f 2 was employed to the release profiles of test formulations and were compared with marketed ciprofloxacin conventional tablets. Drug release mechanism and the kinetics involved were investigated by fitting the release profile data to various kinetic models. It was found that with increasing the proportion of ethylcellulose ether derivative in the matrix, the drug release was significantly extended up to 24 hours. The tablets exhibited zero order or nearly zero order drug transport mechanism. In vivo drug release performance of the developed controlled release tablets and reference conventional tablets containing ciprofloxacin were determined in rabbit serum according to randomized two-way crossover study design using High Performance Liquid Chromatography. Several bioavailability parameters of both the test tablets and conventional tablets including C max⁡, T max⁡ and AUC0-t were compared which showed an optimized C max⁡ and T max⁡ (P < 0.05). A good correlation was obtained

  20. 19 CFR 10.99 - Importation of ethyl alcohol for nonbeverage purposes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Importation of ethyl alcohol for nonbeverage purposes. 10.99 Section 10.99 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND... Provisions Ethyl Alcohol § 10.99 Importation of ethyl alcohol for nonbeverage purposes. (a) If claim is made...

  1. D2 dopaminergic and 5-HT1A serotonergic activity of 2-(1-naphthyl)ethyl- and 2-(2-naphthyl)ethyl amines.

    PubMed

    Šukalović, V; Roglić, G; Husinec, S; Kostić-Rajaćić, S; Andrić, D; Šoškić, Vukić

    2003-11-01

    Several tertiary 2-phenylethyl, 2-(1-naphthyl)ethyl and 2-(2-naphthyl)ethyl amines were synthesized and their binding affinities for dopamine D(1), D(2) and serotonin 5-HT(1A) receptors evaluated in radioligand binding assays. All compounds were inactive in D(1) dopamine radioligand binding assay. The 2-(1-naphthyl)ethyl analogues expressed a low but significant binding affinity for the D(2) and moderate one for the 5-HT(1A) receptor subtypes. Most of the remaining compounds expressed binding affinity at the 5-HT(1A) receptor subtype but were inactive in D(2) receptor binding assay. Based on these results and considering the chemical characteristics of the compounds synthesized and evaluated for dopaminergic and serotonergic activity throughout the present study it can be concluded that hydrophobic type of interaction (stacking or edge-to-face) plays a significant role in the formation of receptor-ligand complexes of 2-(1-naphthyl)ethyl amines. This structural motive can be applied to design and synthesize new, more potent dopaminergic/serotonergic ligands by slight chemical modifications.

  2. 21 CFR 177.1980 - Vinyl chloride-propylene copolymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... contents of the cup are added 3.5 grams of granular sodium peroxide, 0.1 gram of powdered starch, and 0.02... applicable to vinyl chloride-propylene copolymers used in food-packaging adhesives complying with § 175.105...

  3. 21 CFR 177.1980 - Vinyl chloride-propylene copolymers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... contents of the cup are added 3.5 grams of granular sodium peroxide, 0.1 gram of powdered starch, and 0.02... applicable to vinyl chloride-propylene copolymers used in food-packaging adhesives complying with § 175.105...

  4. Uptake of acetaldehyde-modified (ethylated) low-density lipoproteins by mouse peritoneal macrophages.

    PubMed

    Wehr, Hanna; Mirkiewicz, Ewa; Rodo, Maria; Bednarska-Makaruk, Malgorzata

    2002-04-01

    The uptake of acetaldehyde-modified (ethylated) low-density lipoproteins (LDLs) by murine peritoneal macrophages is described and compared with the uptake of acetylated LDLs. The fluorescent marker DiI was used. No competition between ethylated and acetylated LDLs was observed. Ethylated LDL uptake was not inhibited by polyinosinic acid or fucoidin. Our conclusion is that uptake of ethylated and acetylated LDLs can be done by two different receptors.

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

    PubMed

    Jiang, Huidi; Xuan, Guida

    2003-09-01

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

  6. IRIS Toxicological Review of Methyl Ethyl Ketone (2003 Final)

    EPA Science Inventory

    EPA announced the release of the final report, Toxicological Review of Methyl Ethyl Ketone: in support of the Integrated Risk Information System (IRIS). The updated Summary for Methyl Ethyl Ketone and accompanying toxicological review have been added to the IRIS Database....

  7. Electrodialytic Transport Properties of Anion-Exchange Membranes Prepared from Poly(vinyl alcohol) and Poly(vinyl alcohol-co-methacryloyl aminopropyl trimethyl ammonium chloride).

    PubMed

    Jikihara, Atsushi; Ohashi, Reina; Kakihana, Yuriko; Higa, Mitsuru; Kobayashi, Kenichi

    2013-01-02

    Random-type anion-exchange membranes (AEMs) have been prepared by blending poly(vinyl alcohol) (PVA) and the random copolymer-type polycation, poly(vinyl alcohol-co-methacryloyl aminopropyl trimethyl ammonium chloride) at various molar percentages of anion-exchange groups to vinyl alcohol groups, Cpc, and by cross-linking the PVA chains with glutaraldehyde (GA) solution at various GA concentrations, CGA. The characteristics of the random-type AEMs were compared with blend-type AEMs prepared in our previous study. At equal molar percentages of the anion exchange groups, the water content of the random-type AEMs was lower than that of the blend-type AEMs. The effective charge density of the random-type AEMs increased with increasing Cpc and reached a maximum value. Further, the maximum value of the effective charge density increased with increasing CGA. The maximum value of the effective charge density, 0.42 mol/dm3, was obtained for the random-type AEM with Cpc = 4.2 mol % and CGA = 0.15 vol %. A comparison of the random-type and blend-type AEMs with almost the same Cpc showed that the random-type AEMs had lower membrane resistance than the blend-type ones. The membrane resistance and dynamic transport number of the random-type AEM with Cpc = 6.0 mol % and CGA = 0.15 vol % were 4.8 Ω cm2 and 0.83, respectively.

  8. Electrodialytic Transport Properties of Anion-Exchange Membranes Prepared from Poly(vinyl alcohol) and Poly(vinyl alcohol-co-methacryloyl aminopropyl trimethyl ammonium chloride)

    PubMed Central

    Jikihara, Atsushi; Ohashi, Reina; Kakihana, Yuriko; Higa, Mitsuru; Kobayashi, Kenichi

    2012-01-01

    Random-type anion-exchange membranes (AEMs) have been prepared by blending poly(vinyl alcohol) (PVA) and the random copolymer-type polycation, poly(vinyl alcohol-co-methacryloyl aminopropyl trimethyl ammonium chloride) at various molar percentages of anion-exchange groups to vinyl alcohol groups, Cpc, and by cross-linking the PVA chains with glutaraldehyde (GA) solution at various GA concentrations, CGA. The characteristics of the random-type AEMs were compared with blend-type AEMs prepared in our previous study. At equal molar percentages of the anion exchange groups, the water content of the random-type AEMs was lower than that of the blend-type AEMs. The effective charge density of the random-type AEMs increased with increasing Cpc and reached a maximum value. Further, the maximum value of the effective charge density increased with increasing CGA. The maximum value of the effective charge density, 0.42 mol/dm3, was obtained for the random-type AEM with Cpc = 4.2 mol % and CGA = 0.15 vol %. A comparison of the random-type and blend-type AEMs with almost the same Cpc showed that the random-type AEMs had lower membrane resistance than the blend-type ones. The membrane resistance and dynamic transport number of the random-type AEM with Cpc = 6.0 mol % and CGA = 0.15 vol % were 4.8 Ω cm2 and 0.83, respectively. PMID:24958543

  9. Non-enzymatic cyclization of creatine ethyl ester to creatinine.

    PubMed

    Giese, Matthew W; Lecher, Carl S

    2009-10-16

    Creatine ethyl ester was incubated at 37 degrees C in both water and phosphate-buffered saline and the diagnostic methylene resonances in the (1)H NMR spectrum were used to identify the resultant products. It was found that mild aqueous conditions result in the cyclization of creatine ethyl ester to provide inactive creatinine as the exclusive product, and this transformation becomes nearly instantaneous as the pH approaches 7.4. This study demonstrates that mild non-enzymatic conditions are sufficient for the cyclization of creatine ethyl ester into creatinine, and together with previous results obtained under enzymatic conditions suggests that there are no physiological conditions that would result in the production of creatine. It is concluded that creatine ethyl ester is a pronutrient for creatinine rather than creatine under all physiological conditions encountered during transit through the various tissues, thus no ergogenic effect is to be expected from supplementation.

  10. Vinyl flooring in the home is associated with children's airborne butylbenzyl phthalate and urinary metabolite concentrations.

    PubMed

    Just, Allan C; Miller, Rachel L; Perzanowski, Matthew S; Rundle, Andrew G; Chen, Qixuan; Jung, Kyung Hwa; Hoepner, Lori; Camann, David E; Calafat, Antonia M; Perera, Frederica P; Whyatt, Robin M

    2015-01-01

    Prior studies have shown that vinyl flooring as well as the vinyl-softening plasticizers butylbenzyl phthalate (BBzP) and di(2-ethylhexyl) phthalate (DEHP) are associated with asthma and airway inflammation. Although DEHP exposure is primarily dietary, whether home vinyl flooring contributes to indoor air and urinary metabolite concentrations for these two phthalates is unclear. Exposures to BBzP and DEHP were examined in a prospective birth cohort of New York City children (n=239) using: (i) visual observation of potential phthalate containing flooring, (ii) a 2-week home indoor air sample, and (iii) concurrent urinary metabolites in a subset (n=193). The category "vinyl or linoleum" flooring was observed in 135 (56%) of monitored rooms; these rooms had statistically significantly higher indoor air geometric mean concentrations of BBzP (23.9 ng/m(3)) than rooms with wood or carpet flooring (10.6 ng/m(3)). Children from homes with "vinyl or linoleum" flooring also had significantly higher urinary BBzP metabolite concentrations than other children. Indoor air BBzP and urinary metabolite concentrations were correlated positively (Spearman's rho 0.40). By contrast, indoor air DEHP was not associated with flooring type nor with its urinary metabolite concentrations. Vinyl flooring in the home may be an important source of children's exposure to BBzP via indoor air.

  11. Successful topical dissolution of cholesterol gallbladder stones using ethyl propionate.

    PubMed

    Hofmann, A F; Amelsberg, A; Esch, O; Schteingart, C D; Lyche, K; Jinich, H; Vansonnenberg, E; D'Agostino, H B

    1997-06-01

    Topical dissolution of cholesterol gallbladder stones using methyl tert-butyl ether (MTBE) is useful in symptomatic patients judged too ill for surgery. Previous studies showed that ethyl propionate (EP), a C5 ester, dissolves cholesterol gallstones rapidly in vitro, but differs from MTBE in being eliminated so rapidly by the liver that blood levels remain undetectable. Our aim was to test EP as a topical dissolution agent for cholesterol gallbladder stones. Five high-risk patients underwent topical dissolution of gallbladder stones by EP. In three patients, the solvent was instilled via a cholecystostomy tube placed previously to treat acute cholecystitis; in two patients, a percutaneous transhepatic catheter was placed in the gallbladder electively. Gallstone dissolution was assessed by chromatography, by gravimetry, and by catheter cholecystography. Total dissolution of gallstones was obtained in four patients after 6-10 hr of lavage; in the fifth patient, partial gallstone dissolution facilitated basketing of the stones. In two patients, cholesterol dissolution was measured and averaged 30 mg/min. Side effects were limited to one episode of transient hypotension and pain at the infusion site; no patient developed somnolence or nausea. Gallstone elimination was associated with relief of symptoms. EP is an acceptable alternative to MTBE for topical dissolution of cholesterol gallbladder stones in high-risk patients. The lower volatility and rapid hepatic extraction of EP suggest that it may be preferable to MTBE in this investigational procedure.

  12. Stereoselective Formation of Trisubstituted Vinyl Boronate Esters by the Acid-Mediated Elimination of α-Hydroxyboronate Esters

    PubMed Central

    2015-01-01

    The copper-catalyzed diboration of ketones followed by an acid-catalyzed elimination leads to the formation of 1,1-disubstituted and trisubstituted vinyl boronate esters with moderate to good yields and selectivity. Addition of tosic acid to the crude diboration products provides the corresponding vinyl boronate esters upon elimination. The trisubstituted vinyl boronate esters are formed as the (Z)-olefin isomer, which was established by subjecting the products to a Suzuki–Miyaura coupling reaction to obtain alkenes of known geometry. PMID:24915498

  13. Electronic structure and normal vibrations of the 1-ethyl-3-methylimidazolium ethyl sulfate ion pair.

    PubMed

    Dhumal, Nilesh R; Kim, Hyung J; Kiefer, Johannes

    2011-04-21

    Electronic and structural properties of the ion pair 1-ethyl-3-methylimidazolium ethyl sulfate are studied using density functional methods. Three locally stable conformers of the ion pair complex are considered to analyze molecular interactions between its cation and anion. Manifestations of these interactions in the vibrational spectra are discussed and compared with experimental IR and Raman spectroscopy data. NBO analysis and difference electron density coupled with molecular electron density topography are used to interpret the frequency shifts of the normal vibrations of the ion pair, compared to the free anion and cation. Excitation energies of low-lying singlet excited states of the conformers are also studied. The density functional theory results are found to be in a reasonable agreement with experimental UV/vis absorption spectra.

  14. 21 CFR 177.1960 - Vinyl chloride-hexene-1 copolymers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... determined by any suitable analytical procedure of generally accepted applicability. (ii) Inherent viscosity... D1243-79, “Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers,” which is...

  15. In vitro bioactive analysis and antioxidant activity of two species of seaweeds from the Gulf of Mannar.

    PubMed

    Chakraborty, Kajal; Raola, Vamshi Krishna

    2017-09-25

    Evaluation of in vitro standard antioxidant assays, such as 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis-3 ethylbenzothiozoline-6-sulphonic acid diammonium salt (ABTS + ) radical scavenging, lipid peroxidation inhibitory (or thiobarbituric acid formation inhibitory activity) and ferrous ion (Fe +2 ) chelating activities of different solvent extracts of seaweeds, Jania rubens and Kappaphycus alvarezii collected from the Gulf of Mannar of the Peninsular India, were carried out. The methodology utilised bioactivity-guided extraction of seaweed with effective solvent comprised classical chromatographic and spectroscopic techniques. The ethyl acetate extraction of seaweeds displayed significantly greater antioxidant activity than dichloromethane and n-hexane extraction. Bioactivity-guided chromatographic separation of the ethyl acetate extract of seaweeds with potentially greater antioxidant activities, yielded 6α-methoxy-4bβ-methyl-7β-vinyl-1,2,3,4,4a,4b,5,6,7,8,8a,9-dodecahydro-2β-phenanthrenol (1) from J. rubens, whereas K. alvarezii yielded 2β-ethyl-9-oxo-5α-vinyl-1,2,5,5a,6,7,8,9-octahydroheptalene-10,1-carbolactone (2) and methyl-2-ethyl-9-oxo-5α-vinyl-1,2,5,5a,6,7,10,10a-octahydroheptalene-1α-carboxylate (3). Compound 1 displayed significantly greater DPPH scavenging activities (IC 50 0.22 mg/mL) than α-tocopherol (IC 50 0.63 mg/mL). The order of DPPH radical-scavenging activities were compounds 1 > 2 > 3.

  16. Characterization of Vinyl Ester Composites Filled with Carbonized Jatropha seed shell: effect of accelerated weathering

    NASA Astrophysics Data System (ADS)

    Sri Aprilia, N. A.; Khalil, H. P. S. Abdul; Amin, Amri; Meurah Rosnelly, Cut; Fathanah, Ummi; Mariana

    2018-05-01

    The effect of accelerated weathering test of carbonized jatropha seed shell filled vinyl ester biocomposites was investigated. In this study, four loading of carbonized jatropha seed shell and one without loading of vinyl ester biocomposites were used. The samples exposure at several circles time in QUV chamber. The durability of vinyl ester biocomposites filled carbonized jatropha seed shell changes in mechanical properties and weight loss during exposure in UV and condensation. The tensile test and flexural indicated decrease with increasing of carbonized jatropha seed shell loading. The SEM fracture surface of biocomposites looks rough and some carbonized out of the matrix.

  17. An Evaluation of Fracture Toughness of Vinyl Ester Composites Cured under Microwave Conditions

    NASA Astrophysics Data System (ADS)

    Ku, H.; Chan, W. L.; Trada, M.; Baddeley, D.

    2007-12-01

    The shrinkage of vinyl ester particulate composites has been reduced by curing the resins under microwave conditions. The reduction in the shrinkage of the resins by microwaves will enable the manufacture of large vinyl ester composite items possible (H.S. Ku, G. Van Erp, J.A.R. Ball, and S. Ayers, Shrinkage Reduction of Thermoset Fibre Composites during Hardening using Microwaves Irradiation for Curing, Proceedings, Second World Engineering Congress, Kuching, Malaysia, 2002a, 22-25 July, p 177-182; H.S. Ku, Risks Involved in Curing Vinyl Ester Resins Using Microwaves Irradiation. J. Mater. Synth. Proces. 2002b, 10(2), p 97-106; S.H. Ku, Curing Vinyl Ester Particle Reinforced Composites Using Microwaves. J. Comp. Mater., (2003a), 37(22), p 2027-2042; S.H. Ku and E. Siores, Shrinkage Reduction of Thermoset Matrix Particle Reinforced Composites During Hardening Using Microwaves Irradiation, Trans. Hong Kong Inst. Eng., 2004, 11(3), p 29-34). In tensile tests, the yield strengths of samples cured under microwave conditions obtained are within 5% of those obtained by ambient curing; it is also found that with 180 W microwave power, the tensile strengths obtained for all duration of exposure to microwaves are also within the 5% of those obtained by ambient curing. While, with 360 W microwave power, the tensile strengths obtained for all duration of exposure to microwaves are 5% higher than those obtained by ambient curing. Whereas, with 540 W microwave power, the tensile strengths obtained for most samples are 5% below those obtained by ambient curing (H. Ku, V.C. Puttgunta, and M. Trada, Young’s Modulus of Vinyl Ester Composites Cured by Microwave Irradiation: Preliminary Results, J. Electromagnet. Waves Appl., 2007, 20(14), p. 1911-1924). This project, using 33% by weight fly ash reinforced vinyl ester composite [VE/FLYSH (33%)], is to further investigate the difference in fracture toughness between microwave cured vinyl ester particulate composites and those cured

  18. Reactivity of 2-ethyl-1-hexanol in the atmosphere.

    PubMed

    Gallego-Iniesta García, María Paz; Moreno Sanroma, Alberto; Martín Porrero, María Pilar; Tapia Valle, Araceli; Cabañas Galán, Beatriz; Salgado Muñoz, María Sagrario

    2010-04-07

    Rate coefficients at room temperature for the reaction of 2-ethyl-1-hexanol with OH and NO(3) radicals and with Cl atoms have been determined in a 150 L PTFE chamber using GC-FID/SPME and FTIR as detection systems. The rate coefficients k (in units of cm(3) molecule(-1) s(-1)) obtained were: (1.13 +/- 0.31) 10(-11) for the OH reaction, (2.93 +/- 0.92) 10(-15) for the NO(3) reaction and (1.88 +/- 0.25) 10(-10) for the Cl reaction. Despite the high concentrations of 2-ethyl-1-hexanol, especially in indoor air, this is the first kinetic study carried out to date for these reactions. The results are consistent with the expected reactivity given the chemical structure of 2-ethyl-1-hexanol. Calculated atmospheric lifetimes reveal that the dominant loss process for 2-ethyl-1-hexanol is clearly the daytime reaction with the hydroxyl radical.

  19. Process for producing dimethyl ether from synthesis gas

    DOEpatents

    Pierantozzi, R.

    1985-06-04

    This invention pertains to a Fischer Tropsch process for converting synthesis gas to an oxygenated hydrocarbon with particular emphasis on dimethyl ether. Synthesis gas comprising carbon monoxide and hydrogen are converted to dimethyl ether by carrying out the reaction in the presence of an alkali metal-manganese-iron carbonyl cluster incorporated onto a zirconia-alumina support.

  20. Process for producing dimethyl ether form synthesis gas

    DOEpatents

    Pierantozzi, Ronald

    1985-01-01

    This invention pertains to a Fischer Tropsch process for converting synthesis gas to an oxygenated hydrocarbon with particular emphasis on dimethyl ether. Synthesis gas comprising carbon monoxide and hydrogen are converted to dimethyl ether by carrying out the reaction in the presence of an alkali metal-manganese-iron carbonyl cluster incorporated onto a zirconia-alumina support.

  1. Wholly Aromatic Ether-imides. Potential Materials for n-Type Semiconductors

    NASA Technical Reports Server (NTRS)

    Dingemans, Theo J.; St.Clair, Terry L.; Samulski, Edward T.; Bushnell, Dennis M. (Technical Monitor)

    2002-01-01

    We report on the synthesis and characterization of a novel series low-molar-mass ether-imide rod-shaped model compounds. All ether-imides were obtained by terminating the appropriate rigid core dianhydride, i.e. pyromellitic dianhydride (PMDA), 1,4,5,8-naphthalenetetracarboxylic dianhydride (NDA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), and 3,3,4,4'-oxydiphthalic dianhydride (ODPA) with three flexible aryl-ether tails of different chain length. The mono-functional aryl-ether amines, i.e. 4-(3-phenoxy-phenoxy)-phenylamine (2) and 4-(3-phenoxy-3-phenoxy-phenoxy)-phenylamine (4), were synthesized using standard fluoro-displacement and Ullmann condensation techniques. The corresponding ether-imide model compounds were obtained in high yields using a one-step solution imidization procedure. Increasing the number of meta-substituted aryl-ether units reduces the melt transition temperatures and at the same time it increases the solubility of the model compounds. Most model compounds are crystalline solids and form isotropic melts upon heating. 2,7-Bis-(-4-phenoxy-phenyl)-benzo[Imn][3,8]phenanthroline1,3,6,8-tetraone (NDA-n0), however, displays a smectic A (SA) when cooled from the isotropic phase, followed by what appears to be either a highly ordered smectic phase or a, columnar phase. This is the first example, known to date, in which a mesophase is detected in a wholly aromatic ether-imide compound. For all compounds we present spectroscopic data and X-ray diffraction data. Cyclic voltammetry was used to determine the redox behavior and pertinent energy levels of the model compounds.

  2. Pressure and Temperature Dependence of the Reaction of Vinyl Radical with Ethylene

    NASA Technical Reports Server (NTRS)

    Ismail, Huzeifa; Goldsmith, C. Franklin; Abel, Paul R.; Howe, Pui-Teng; Fahr, Askar; Halpern, Joshua B.; Jusinski, Leonard E.; Georgievskii, Yuri; Taatjes, Craig A.; Green, William H.

    2007-01-01

    This work reports measurements of absolute rate coefficients and Rice-Ramsperger-Kassel-Marcus (RRKM) master equation simulations of the C2H3 + C2H4 reaction. Direct kinetic studies were performed over a temperature range of 300-700 K and pressures of 20 and 133 mbar. Vinyl radicals (H2C=CH) were generated by laser photolysis of vinyl iodide (C2H31) at 266 nm, and time-resolved absorption spectroscopy was used to probe vinyl radicals through absorption at 423.2 nm. Measurements at 20 mbar are in good agreement with previous determinations at higher temperature. A weighted three-parameter Arrhenius fit to the experimental rate constant at 133 mbar, with the temperature exponent fixed, gives k = (7 +/- 1) x 10(exp -l4) cu cm/molecule/s (T/298 K)(exp 2) exp[-(1430 +/- 70) K/T]. RRKM master equation simulations, based on G3 calculations of stationary points on the C4H7 potential energy surface, were carried out to predict rate coefficients and product branching fractions. The predicted branching to 1-methylallyl product is relatively small under the conditions of the present experiments but increases as the pressure is lowered. Analysis of end products of 248 nm photolysis of vinyl iodide/ethylene mixtures at total pressures between 27 and 933 mbar provides no direct evidence for participation of I -methylallyl.

  3. 40 CFR 721.10481 - Siloxanes and Silicones, Me vinyl, hydroxy-terminated, reaction products with silica.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Siloxanes and Silicones, Me vinyl... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10481 Siloxanes and Silicones, Me... uses subject to reporting. (1) The chemical substance identified as Siloxanes and Silicones, Me vinyl...

  4. 40 CFR 721.10481 - Siloxanes and Silicones, Me vinyl, hydroxy-terminated, reaction products with silica.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Siloxanes and Silicones, Me vinyl... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10481 Siloxanes and Silicones, Me... uses subject to reporting. (1) The chemical substance identified as Siloxanes and Silicones, Me vinyl...

  5. 40 CFR 61.65 - Emission standard for ethylene dichloride, vinyl chloride and polyvinyl chloride plants.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Emission standard for ethylene... AIR POLLUTANTS National Emission Standard for Vinyl Chloride § 61.65 Emission standard for ethylene dichloride, vinyl chloride and polyvinyl chloride plants. An owner or operator of an ethylene dichloride...

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

    NASA Astrophysics Data System (ADS)

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

    2018-05-01

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

  7. 40 CFR 721.10017 - Amine terminated bisphenol A diglycidyl ether polymer (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

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

  8. 40 CFR 721.1580 - Disubstituted benzene ether, polymer with substituted phenol (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Disubstituted benzene ether, polymer... Significant New Uses for Specific Chemical Substances § 721.1580 Disubstituted benzene ether, polymer with... chemical substance generically identified as disubstituted benzene ether, polymer with substituted phenol...

  9. 40 CFR 721.10017 - Amine terminated bisphenol A diglycidyl ether polymer (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

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

  10. 40 CFR 721.1580 - Disubstituted benzene ether, polymer with substituted phenol (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Disubstituted benzene ether, polymer... Significant New Uses for Specific Chemical Substances § 721.1580 Disubstituted benzene ether, polymer with... chemical substance generically identified as disubstituted benzene ether, polymer with substituted phenol...

  11. 40 CFR 721.1580 - Disubstituted benzene ether, polymer with substituted phenol (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Disubstituted benzene ether, polymer... Significant New Uses for Specific Chemical Substances § 721.1580 Disubstituted benzene ether, polymer with... chemical substance generically identified as disubstituted benzene ether, polymer with substituted phenol...

  12. 40 CFR 721.1580 - Disubstituted benzene ether, polymer with substituted phenol (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Disubstituted benzene ether, polymer... Significant New Uses for Specific Chemical Substances § 721.1580 Disubstituted benzene ether, polymer with... chemical substance generically identified as disubstituted benzene ether, polymer with substituted phenol...

  13. 40 CFR 721.1580 - Disubstituted benzene ether, polymer with substituted phenol (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Disubstituted benzene ether, polymer... Significant New Uses for Specific Chemical Substances § 721.1580 Disubstituted benzene ether, polymer with... chemical substance generically identified as disubstituted benzene ether, polymer with substituted phenol...

  14. 40 CFR 721.10017 - Amine terminated bisphenol A diglycidyl ether polymer (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

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

  15. 40 CFR 721.10017 - Amine terminated bisphenol A diglycidyl ether polymer (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

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

  16. 40 CFR 721.10017 - Amine terminated bisphenol A diglycidyl ether polymer (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

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

  17. Rotational spectroscopy of isotopic vinyl cyanide, H2CCHCN, in the laboratory and in space

    NASA Astrophysics Data System (ADS)

    Müller, Holger S. P.; Belloche, Arnaud; Menten, Karl M.; Comito, Claudia; Schilke, Peter

    2008-09-01

    The rotational spectra of singly substituted 13C and 15N isotopic species of vinyl cyanide have been studied in natural abundances between 64 and 351 GHz. In combination with previous results, greatly improved spectroscopic parameters have been obtained which in turn helped to identify transitions of the 13C species for the first time in space through a molecular line survey of the extremely line-rich interstellar source Sagittarius B2(N) in the 3 mm region with some additional observations at 2 mm. The 13C species are detected in two compact (˜2.3″), hot (170 K) cores with a column density of ˜3.8×10 and 1.1×10cm, respectively. In the main source, the so-called “Large Molecule Heimat”, we derive an abundance of 2.9×10 for each 13C species relative to H2. An isotopic ratio 12C/13C of 21 has been measured. Based on a comparison to the column densities measured for the 13C species of ethyl cyanide also detected in this survey, it is suggested that the two hot cores of Sgr B2(N) are in different evolutionary stages. Supplementary laboratory data for the main isotopic species recorded between 92 and 342 GHz permitted an improvement of its spectroscopic parameters as well.

  18. “Click, Click, Cyclize”: A DOS Approach to Sultams Utilizing Vinyl Sulfonamide Linchpins

    PubMed Central

    Zhou, Aihua; Rayabarapu, Dinesh; Hanson, Paul R.

    2009-01-01

    A diversity-oriented synthesis (DOS) strategy termed “Click, Click, Cyclize” is reported. This approach relies on functional group (FG) pairing between a vinyl sulfonamide and an array of functional groups to synthesize skeletally diverse sultams. Several FG pairing pathways on central tertiary vinyl sulfonamide linchpins have been developed including intramolecular Heck, aza-Michael, ring-closing enyne metathesis, Pauson—Khand, and chemoselective oxidation/Baylis—Hillman reactions. PMID:19115841

  19. Contribution of citrulline to the formation of ethyl carbamate during Chinese rice wine production.

    PubMed

    Wang, Peihong; Sun, Junyong; Li, Xiaomin; Wu, Dianhui; Li, Tong; Lu, Jian; Chen, Jian; Xie, Guangfa

    2014-04-01

    Ethyl carbamate is a well-known carcinogen and widely occurs in Chinese rice wine. To provide more clues to minimise ethyl carbamate accumulation, the levels of possible precursors of ethyl carbamate in Chinese rice wine were investigated by HPLC. Studies of the possible precursors of ethyl carbamate in Chinese raw rice wine with various additives and treatments indicated that significant amounts of urea can account for ethyl carbamate formation. It was also recognised that citrulline is another important precursor that significantly affects ethyl carbamate production during the boiling procedure used in the Chinese rice wine manufacturing process. Besides urea and citrulline, arginine was also found to be an indirect ethyl carbamate precursor due to its ability to form urea and citrulline by microorganism metabolism.

  20. IRIS TOXICOLOGICAL REVIEW OF DECABROMODIPHENYL ETHER (EXTERNAL REVIEW DRAFT)

    EPA Science Inventory

    The U.S. EPA is conducting a peer review of the scientific basis supporting the human health hazard and dose-response assessments of congeners of polybrominated diphenyl ethers (PDBEs), this review is about Decabromodiphenyl Ether, or commonly referred to as decaBDE (BDE-209). ...

  1. Low dielectric fluorinated poly(phenylene ether ketone) film and coating

    NASA Technical Reports Server (NTRS)

    Cassidy, Patrick E. (Inventor); Tullos, Gordon L. (Inventor); St.clair, Anne K. (Inventor)

    1990-01-01

    The present invention relates to film and coating materials prepared from novel fluorinated poly(phenylene ether ketones). A fluorinated poly(phenylene ether ketone) is prepared by reacting a bisphenol with 1,1,1,3,3,3 hexafluoro-2,2-bis 4-(4-halobenzoyl) phenyl propane (wherein halo is fluoro or chloro), which is a novel monomer formed as the reaction product of halobenzene (wherein halo is fluoro or chloro) and 1,1,1,3,3,3 hexafluoro-2,2-bis (p-chloro formyl phenyl) propane. Especially beneficial results of this invention are that films and coating materials prepared from the novel fluorinated poly(phenylene ether ketone) are essentially optically transparent/colorless and have a lower dielectric constant than otherwise comparable, commercially available poly(phenylene ether ketones). Moreover, unlike the otherwise comparable commercially available materials, the novel fluorinated poly(phenylene ether ketones) of the present invention can be solution cast or sprayed to produce the films and coatings. Furthermore, the long term thermal stability of the polymers of the present invention is superior to that of the commercially available materials.

  2. Fungal degradation of an acetolactate synthase (ALS) inhibitor pyrazosulfuron-ethyl in soil.

    PubMed

    Sondhia, Shobha; Waseem, Uzma; Varma, R K

    2013-11-01

    Owing to reported phytotoxicity of some sulfonylurea class of herbicides in number of sensitive crops and higher persistence in soil, present study was conducted to isolate and identify pyrazosulfuron-ethyl degrading fungi from soil of rice field. Penicillium chrysogenum and Aspergillus niger, were isolated and identified from rhizospere soil of rice field, as potent pyrazosulfuron-ethyl degrading fungi. Degradation of pyrazosulfuron-ethyl by P. chrysogenum and A. niger, yielded transformation products/metabolites which were identified and characterized by LC/MS/MS. The rate of dissipation of pyrazosulfuron-ethyl was found higher in soil of rice field and soil inoculated with P. chrysogenum. This showed important route of degradation of pyrazosulfuron-ethyl by microbes apart from chemical degradation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Thermal oxidative degradation reactions of linear perfluoroalkyl ethers

    NASA Technical Reports Server (NTRS)

    Jones, W. R., Jr.; Paclorek, K. J. L.; Ito, T. I.; Kratzer, R. H.

    1983-01-01

    Thermal and thermal oxidative stability studies were performed on linear perfluoroalkyl ether fluids. The effect on degradation by metal catalysts and degradation inhibitors is reported. The linear perfluoroalkyl ethers are inherently unstable at 316 C in an oxidizing atmosphere. The metal catalysts greatly increased the rate of degradation in oxidizing atmospheres. In the presence of these metals in an oxidizing atmosphere, the degradation inhibitors were highly effective in arresting degradation at 288 C. However, the inhibitors had only limited effectiveness at 316 C. The metals promote degradation by chain scission. Based on elemental analysis and oxygen consumption data, the linear perfluoroalkyl ether fluids have a structural arrangement based on difluoroformyl and tetrafluoroethylene oxide units, with the former predominating. Previously announced in STAR as N82-26468

  4. 75 FR 5578 - Submission for OMB Review; Comment Request-Flammability Standards for Clothing Textiles and Vinyl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-03

    ... Standards for Clothing Textiles and Vinyl Plastic Film AGENCY: Consumer Product Safety Commission. ACTION... Commission's flammability standards for clothing textiles and vinyl plastic film. DATES: Written comments on... collection requirements should be captioned ``Clothing Textiles and Film, Collection of Information'' and...

  5. Bis(chloroethyl)ether (BCEE)

    Integrated Risk Information System (IRIS)

    Bis ( chloroethyl ) ether ( BCEE ) ; CASRN 111 - 44 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments fo

  6. Bis(chloromethyl)ether (BCME)

    Integrated Risk Information System (IRIS)

    Bis ( chloromethyl ) ether ( BCME ) ; CASRN 542 - 88 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments f

  7. Chloromethyl methyl ether (CMME)

    Integrated Risk Information System (IRIS)

    Chloromethyl methyl ether ( CMME ) ; CASRN 107 - 30 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments fo

  8. Triethylene glycol monobutyl ether

    Integrated Risk Information System (IRIS)

    Triethylene glycol monobutyl ether ; CASRN 143 - 22 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments fo

  9. p,p\\'-Dibromodiphenyl ether

    Integrated Risk Information System (IRIS)

    p , p ' - Dibromodiphenyl ether ; CASRN 2050 - 47 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for

  10. Triethylene glycol monoethyl ether

    Integrated Risk Information System (IRIS)

    Triethylene glycol monoethyl ether ; CASRN 112 - 50 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments fo

  11. Propylene glycol monoethyl ether

    Integrated Risk Information System (IRIS)

    Propylene glycol monoethyl ether ; CASRN 52125 - 53 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments fo

  12. Biodegradation and detoxification of chlorimuron-ethyl by Enterobacter ludwigii sp. CE-1.

    PubMed

    Pan, Xiong; Wang, Saige; Shi, Nan; Fang, Hua; Yu, Yunlong

    2018-04-15

    The application of the herbicide chlorimuron-ethyl has a lasting toxic effect on some succession crops. Here, a bacterium capable of utilizing chlorimuron-ethyl as the sole source of nitrogen was isolated from the contaminated soil and was identified as Enterobacter ludwigii sp. CE-1, and its detoxification and degradation of the herbicide were then examined. The biodegradation of chlorimuron-ethyl by the isolate CE-1 was significantly accelerated with increasing concentration (1-10mg/l) and temperature (20-40°C). The optimal pH for the degradation of chlorimuron-ethyl by the isolate CE-1 was pH 7.0. A pathway for the biodegradation of chlorimuron-ethyl by the isolate CE-1 was proposed, in which it could be first converted into 2-amino-4-chloro-6-methoxypyrimidine and an intermediate product by the cleavage of the sulfonylurea bridge and then transformed into saccharin via hydrolysis and amidation. The plant height and fresh weight of corn that had been incubated in nutrient solution containing 0.2mg/l of chlorimuron-ethyl significantly recovered to 83.9% and 83.1% compared with those in the uninoculated control, although the root growth inhibition of chlorimuron-ethyl could not be alleviated after inoculation for 14 d. The results indicate that the isolate CE-1 is a promising bacterial resource for the biodegradation and detoxification of chlorimuron-ethyl. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Structure-property study of keto-ether polyimides

    NASA Technical Reports Server (NTRS)

    Dezern, James F.; Croall, Catharine I.

    1991-01-01

    As part of an on-going effort to develop an understanding of how changes in the chemical structure affect polymer properties, an empirical study was performed on polyimides containing only ether and/or carbonyl connecting groups in the polymer backbone. During the past two decades the structure-property relationships in linear aromatic polyimides have been extensively investigated. More recently, work has been performed to study the effect of isomeric attachment of keto-ether polyimides on properties such as glass transition temperature and solubility. However, little work has been reported on the relation of polyimide structure to mechanical properties. The purpose of this study was to determine the effect of structural changes in the backbone of keto-ether polyimides on their mechanical properties, specifically, unoriented thin film tensile properties. This study was conducted in two stages. The purpose of the initial stage was to examine the physical and mechanical properties of a representative group (four) of polyimide systems to determine the optimum solvent and cure cycle requirements. These optimum conditions were then utilized in the second stage to prepare films of keto-ether polyimides which were evaluated for mechanical and physical properties. All of the polyimides were prepared using isomers of oxydianiline (ODA) and diaminobenzophenone (DABP) in combination with 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA) and 4,4'-oxydiphthalic anhydride (ODPA).

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

    PubMed

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

    2001-02-02

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

  15. Vinyl flooring in the home is associated with children’s airborne butylbenzyl phthalate and urinary metabolite concentrations

    PubMed Central

    Just, Allan C.; Miller, Rachel L.; Perzanowski, Matthew S.; Rundle, Andrew G.; Chen, Qixuan; Jung, Kyung Hwa; Hoepner, Lori; Camann, David E.; Calafat, Antonia M.; Perera, Frederica P.; Whyatt, Robin M.

    2015-01-01

    Prior studies have shown that vinyl flooring, as well as the vinyl-softening plasticizers butylbenzyl phthalate (BBzP) and di(2-ethylhexyl) phthalate (DEHP), are associated with asthma and airway inflammation. While DEHP exposure is primarily dietary, whether home vinyl flooring contributes to indoor air and urinary metabolite concentrations for these two phthalates is unclear. Exposures to BBzP and DEHP were examined in a prospective birth cohort of New York City children (n=239) using: (1) visual observation of potential phthalate containing flooring, (2) a two-week home indoor air sample, and (3) concurrent urinary metabolites in a subset (n=193). The category “vinyl or linoleum” flooring was observed in 135 (56%) of monitored rooms; these rooms had statistically significantly higher indoor air geometric mean concentrations of BBzP (23.9 ng/m3) than rooms with wood or carpet flooring (10.6 ng/m3). Children from homes with “vinyl or linoleum” flooring also had significantly higher urinary BBzP metabolite concentrations than other children. Indoor air BBzP and urinary metabolite concentrations were correlated positively (Spearman’s rho 0.40). By contrast, indoor air DEHP was not associated with flooring type nor with its urinary metabolite concentrations. Vinyl flooring in the home may be an important source of children’s exposure to BBzP via indoor air. PMID:25690585

  16. Poly(vinyl Chloride) Photostabilization in the Presence of Schiff Bases Containing a Thiadiazole Moiety.

    PubMed

    Shaalan, Naser; Laftah, Nawres; El-Hiti, Gamal A; Alotaibi, Mohammad Hayal; Muslih, Raad; Ahmed, Dina S; Yousif, Emad

    2018-04-15

    Five Schiff bases containing a thiadiazole moiety have been used as poly(vinyl chloride) photostabilizers at low concentrations. The efficiency of Schiff bases as photostabilizers was investigated using various techniques, for example, the changes in poly(vinyl chloride) infrared spectra, molecular weight, chain scission quantum yield, and surface morphology were monitored upon irradiation with an ultraviolet light. Evidently, all the additives used inhibited poly(vinyl chloride) photodegradation at a significant level. The most efficient Schiff base exhibited a high level of aromaticity and contained a hydroxyl group. It seems possible that such photostabilization could be due to the direct absorption of ultraviolet radiation by the additives. In addition, Schiff bases could act as radical scavengers and proton transfer facilitators to stabilize the polymeric materials.

  17. Chemo-enzymatic synthesis of vinyl and l-ascorbyl phenolates and their inhibitory effects on advanced glycation end products.

    PubMed

    Hwang, Seung Hwan; Wang, Zhiqiang; Lim, Soon Sung

    2017-01-01

    This study successfully established the feasibility of a two-step chemo-enzymatic synthesis of l-ascorbyl phenolates. Intermediate vinyl phenolates were first chemically produced and then underwent trans-esterification with l-ascorbic acid in the presence of Novozyme 435® (Candida Antarctica lipase B) as a catalyst. Twenty vinyl phenolates and 11 ascorbyl phenolates were subjected to in vitro bioassays to investigate their inhibitory activity against advanced glycation end products (AGEs). Among them, vinyl 4-hydroxycinnamate (17VP), vinyl 4-hydroxy-3-methoxycinnamate (18VP), vinyl 4-hydroxy-3,5-dimethoxycinnamate (20VP), ascorbyl 4-hydroxy-3-methoxycinnamate (18AP) and ascorbyl 3,4-dimethoxycinnamate (19AP) showed 2-10 times stronger inhibitory activities than positive control (aminoguanidine and its precursors). These results indicated that chemo-enzymatically synthesized compounds have AGE inhibitory effect and thus are effective in either preventing or retarding glycation protein formation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. The development and characterization of degradable poly(vinyl ester) and poly(vinyl ester)/PEO block copolymers

    NASA Astrophysics Data System (ADS)

    Lipscomb, Corinne Elizabeth

    The development of biodegradable materials is a challenging and important problem in polymer science. A review of the state of the art in degradable materials is presented, which reveals that current biodegradable materials do not exhibit the thermal or mechanical properties necessary for widespread applications. One strategy for toughening polymeric materials, which has previously been applied to non-degradable thermoplastics and thermoplastic elastomers, is the formation of block copolymers. Poly(vinyl esters) (PVE) homopolymers are known to have a wide range of properties, but PVE block copolymers comprise a class of inexpensive and (bio)degradable materials that were previously unknown. Therefore, the synthesis and properties of these block copolymers were explored in an effort to develop robust degradable materials. This thesis research probes the reaction conditions necessary for the reversible-addition fragmentation chain transfer (RAFT) polymerization and chain extension reactions of vinyl ester monomers. PVE di- and triblock copolymers are synthesized and studied, and the triblock copolymers display extremely poor toughness due to their relatively low molecular weights in light of the high entanglement molecular weight of the poly(vinyl acetate) center block. Attempts to improve the mechanical properties of these materials focus on the incorporation of poly(ethylene oxide) (PEO) as a low entanglement molecular weight and biocompatible center block in PVE-containing triblock copolymers. Depending on the choice of PVE endblocks and the overall polymer composition, crystallization of the PEO block can be controlled, confined, or inhibited. Polymers in which PEO crystallization is completely inhibited exhibit enhanced mechanical properties and behave as weak thermoplastics. In order to understand the relationship between the inhibition of PEO crystallization and the mechanical properties of PVE/PEO materials, these polymers were studied using dynamic

  19. Screening rhodium metallopeptide libraries "on bead": asymmetric cyclopropanation and a solution to the enantiomer problem.

    PubMed

    Sambasivan, Ramya; Ball, Zachary T

    2012-08-20

    Searching with a beady eye: A high-throughput, on-bead screen of rhodium metallopeptide catalysts was developed in a 96-well format for asymmetric cyclopropanation. Different sequences of natural L-amino acids have been identified that produce opposite product enantiomers. In addition to styrene derivatives, high enantioselectivity is observed for vinyl ether and vinyl amine derivatives. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Catalyst-free ethyl biodiesel production from rice bran under subcritical condition

    NASA Astrophysics Data System (ADS)

    Zullaikah, Siti; Afifudin, Riza; Amalia, Rizky

    2015-12-01

    In-situ ethyl biodiesel production from rice bran under subcritical water and ethanol with no catalyst was employed. This process is environmentally friendly and is very flexible in term of feedstock utilization since it can handle relatively high moisture and free fatty acids (FFAs) contents. In addition, the alcohol, i.e. bioethanol, is a non-toxic, biodegradable, and green raw material when produced from non-edible biomass residues, leading to a 100% renewable biodiesel. The fatty acid ethyl esters (FAEEs, ethyl biodiesel) are better than fatty acid methyl esters (FAMEs, methyl biodiesel) in terms of fuel properties, including cetane number, oxidation stability and cold flow properties. The influences of the operating variables such as reaction time (1 - 10 h), ethanol concentration (12.5 - 87.5%), and pressurizing gas (N2 and CO2) on the ethyl biodiesel yield and purity have been investigated systematically while the temperature and pressure were kept constant at 200 °C and 40 bar. The optimum results were obtained at 5 h reaction time and 75% ethanol concentration using CO2 as compressing gas. Ethyl biodiesel yield and purity of 58.78% and 61.35%, respectively, were obtained using rice bran with initial FFAs content of 37.64%. FFAs level was reduced to 14.22% with crude ethyl biodiesel recovery of 95.98%. Increasing the reaction time up to 10 h only increased the yield and purity by only about 3%. Under N2 atmosphere and at the same operating conditions (5h and 75% ethanol), ethyl biodiesel yield and purity decreased to 54.63% and 58.07%, respectively, while FFAs level was increased to 17.93% and crude ethyl biodiesel recovery decreased to 87.32%.